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Ham J, Kim HE, Kim JJ, Seok JH, Kim E, Park JY, Lee B, Oh J. Differential relationship of observer-rated and self-rated depression and anxiety scales with heart rate variability features. Front Psychiatry 2023; 14:1124550. [PMID: 37077280 PMCID: PMC10109339 DOI: 10.3389/fpsyt.2023.1124550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 03/13/2023] [Indexed: 04/21/2023] Open
Abstract
Heart rate variability (HRV) is a known psychophysiological marker for diverse psychiatric symptoms. In this study, we aimed to explore the potential for clinical use of HRV by investigating the interrelationship between HRV indices and clinical measures mainly used to assess depressive and anxious symptoms. Participants who reported depressive and anxious symptoms were designated into the following groups: group 1, clinician-rated and self-rated depression; group 2, only self-rated depression; group 3, clinician-rated and self-rated anxiety; group 4, only self-rated anxiety. Statistical comparisons were performed between these groups to investigate the association between HRV and clinical measures. As a result, HRV variables showed significant correlations only with the clinician-rated assessments. Moreover, both time and frequency domain HRV indices were significantly different between groups 1 and 2, but groups 3 and 4 showed significant differences only in frequency domain HRV indices. Our study showed that HRV is an objective indicator for depressive or anxious symptoms. Additionally, it is considered a potential indicator for predicting the severity or state of depressive symptoms rather than of anxious symptoms. This study will contribute to increasing the diagnostic utility of discriminating those symptoms based on HRV in the future.
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Affiliation(s)
- Jinsil Ham
- Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
- Institute of Behavioral Sciences in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Hesun Erin Kim
- Institute of Behavioral Sciences in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jae-Jin Kim
- Institute of Behavioral Sciences in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Department of Psychiatry, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jeong-Ho Seok
- Institute of Behavioral Sciences in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Department of Psychiatry, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Eunjoo Kim
- Institute of Behavioral Sciences in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Department of Psychiatry, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jin Young Park
- Institute of Behavioral Sciences in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Department of Psychiatry, Yongin Severance Hospital, Yonsei University College of Medicine, Yongin, Republic of Korea
| | - Boreom Lee
- Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
- *Correspondence: Boreom Lee,
| | - Jooyoung Oh
- Institute of Behavioral Sciences in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Department of Psychiatry, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
- Jooyoung Oh,
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Ham J, Yoo HJ, Kim J, Lee B. Vowel speech recognition from rat electroencephalography using long short-term memory neural network. PLoS One 2022; 17:e0270405. [PMID: 35737731 PMCID: PMC9223328 DOI: 10.1371/journal.pone.0270405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 06/09/2022] [Indexed: 11/24/2022] Open
Abstract
Over the years, considerable research has been conducted to investigate the mechanisms of speech perception and recognition. Electroencephalography (EEG) is a powerful tool for identifying brain activity; therefore, it has been widely used to determine the neural basis of speech recognition. In particular, for the classification of speech recognition, deep learning-based approaches are in the spotlight because they can automatically learn and extract representative features through end-to-end learning. This study aimed to identify particular components that are potentially related to phoneme representation in the rat brain and to discriminate brain activity for each vowel stimulus on a single-trial basis using a bidirectional long short-term memory (BiLSTM) network and classical machine learning methods. Nineteen male Sprague-Dawley rats subjected to microelectrode implantation surgery to record EEG signals from the bilateral anterior auditory fields were used. Five different vowel speech stimuli were chosen, /a/, /e/, /i/, /o/, and /u/, which have highly different formant frequencies. EEG recorded under randomly given vowel stimuli was minimally preprocessed and normalized by a z-score transformation to be used as input for the classification of speech recognition. The BiLSTM network showed the best performance among the classifiers by achieving an overall accuracy, f1-score, and Cohen’s κ values of 75.18%, 0.75, and 0.68, respectively, using a 10-fold cross-validation approach. These results indicate that LSTM layers can effectively model sequential data, such as EEG; hence, informative features can be derived through BiLSTM trained with end-to-end learning without any additional hand-crafted feature extraction methods.
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Affiliation(s)
- Jinsil Ham
- Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Hyun-Joon Yoo
- Department of Physical Medicine and Rehabilitation, Korea University Anam Hospital, Korea University College of Medicine, Seoul, South Korea
| | - Jongin Kim
- Deepmedi Research Institute of Technology, Deepmedi Inc., Seoul, South Korea
| | - Boreom Lee
- Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
- * E-mail:
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Abstract
Precise monitoring of the brain after a stroke is essential for clinical decision making. Due to the non-invasive nature and high temporal resolution of electroencephalography (EEG), it is widely used to evaluate real-time cortical activity. In this study, we investigated the stroke-related EEG biomarkers and developed a predictive model for quantifying the structural brain damage in a focal cerebral ischaemic rat model. We enrolled 31 male Sprague-Dawley rats and randomly assigned them to mild stroke, moderate stroke, severe stroke, and control groups. We induced photothrombotic stroke targeting the right auditory cortex. We then acquired EEG signal responses to sound stimuli (frequency linearly increasing from 8 to 12 kHz with 750 ms duration). Power spectral analysis revealed a significant correlation of the relative powers of alpha, theta, delta, delta/alpha ratio, and (delta + theta)/(alpha + beta) ratio with the stroke lesion volume. The auditory evoked potential analysis revealed a significant association of amplitude and latency with stroke lesion volume. Finally, we developed a multiple regression model combining EEG predictors for quantifying the ischaemic lesion (R2 = 0.938, p value < 0.001). These findings demonstrate the potential application of EEG as a valid modality for monitoring the brain after a stroke.
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Affiliation(s)
- Hyun-Joon Yoo
- Department of Physical Medicine and Rehabilitation, Korea University Anam Hospital, Korea University College of Medicine, 73 Goryeodae-ro, Seongbuk-gu, Seoul, 02841, Korea
| | - Jinsil Ham
- Department of Biomedical Science and Engineering (BMSE), Institute Integrated Technology (IIT), Gwangju Institute of Science and Technology (GIST), 123 Cheomdan-gwagiro, Buk-gu, Gwangju, 61005, Korea
| | - Nguyen Thanh Duc
- Department of Biomedical Science and Engineering (BMSE), Institute Integrated Technology (IIT), Gwangju Institute of Science and Technology (GIST), 123 Cheomdan-gwagiro, Buk-gu, Gwangju, 61005, Korea
| | - Boreom Lee
- Department of Biomedical Science and Engineering (BMSE), Institute Integrated Technology (IIT), Gwangju Institute of Science and Technology (GIST), 123 Cheomdan-gwagiro, Buk-gu, Gwangju, 61005, Korea.
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Abstract
Epilepsy is a neurological disorder characterized by unpredictable seizures,
which are bursts of electrical activity that tempo-rarily affect the brain.
Cereblon (CRBN), a DCAFs (DDB1 and
CUL4associated factors),
is a well-established protein associated with human mental retardation. Being a
substrate receptor of the cullin-RING E3 ubiquitin ligase (CRL) 4 complex, CRBN
mediates ubiquitination of several substrates and conducts multiple biological
processes. In the central nervous system, the large-conductance
Ca2+-activated K+ (BKCa) channel, which is the
substrate of CRBN, is an important regulator of epilepsy. Despite the functional
role and importance of CRBN in the brain, di-rect injection of
pentylenetetrazole (PTZ) to induce seizures in CRBN knock-out mice has not been
challenged. In this study, we investigated the effect of PTZ in CRBN knock-out
mice. Here, we demonstrate that, compared with WT mice, CRBN knock-out mice do
not show the intensification of seizures by PTZ induction. Moreover,
electroencephalography recordings were also performed in the brains of both WT
and CRBN knockout mice to identify the absence of significant differences in the
pattern of seizure activities. Consistently, immunoblot analysis for validating
the protein level of the CRL4 complex containing CRBN (CRL4Crbn) in
the mouse brain was carried out. Taken together, we found that the deficiency of
CRBN does not affect PTZ-induced seizure.
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Affiliation(s)
- Seung-Je Jeon
- School of Life Sciences and Integrated Institute of Biomedical Research (IIBR), Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Jinsil Ham
- Department of Biomedical Science and Engineering (BMSE), Institute of Integrated Technology (IIT), Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Chul-Seung Park
- School of Life Sciences and Integrated Institute of Biomedical Research (IIBR), Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Boreom Lee
- Department of Biomedical Science and Engineering (BMSE), Institute of Integrated Technology (IIT), Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
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Oh J, Ham J, Cho D, Park JY, Kim JJ, Lee B. The Effects of Transcranial Direct Current Stimulation on the Cognitive and Behavioral Changes After Electrode Implantation Surgery in Rats. Front Psychiatry 2019; 10:291. [PMID: 31156472 PMCID: PMC6531794 DOI: 10.3389/fpsyt.2019.00291] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 04/15/2019] [Indexed: 11/22/2022] Open
Abstract
Postoperative delirium can lead to increased morbidity and mortality, and may even be a potentially life-threatening clinical syndrome. However, the neural mechanism underlying this condition has not been fully understood and there is little knowledge regarding potential preventive strategies. To date, investigation of transcranial direct current stimulation (tDCS) for the relief of symptoms caused by neuropsychiatric disorders and the enhancement of cognitive performance has led to promising results. In this study, we demonstrated that tDCS has a possible effect on the fast recovery from delirium in rats after microelectrode implant surgery, as demonstrated by postoperative behavior and neurophysiology compared with sham stimulation. This is the first study to describe the possible effects of tDCS for the fast recovery from delirium based on the study of both electroencephalography and behavioral changes. Postoperative rats showed decreased attention, which is the core symptom of delirium. However, anodal tDCS over the right frontal area immediately after surgery exhibited positive effects on acute attentional deficit. It was found that relative power of theta was lower in the tDCS group than in the sham group after surgery, suggesting that the decrease might be the underlying reason for the positive effects of tDCS. Connectivity analysis revealed that tDCS could modulate effective connectivity and synchronization of brain activity among different brain areas, including the frontal cortex, parietal cortex, and thalamus. It was concluded that anodal tDCS on the right frontal regions may have the potential to help patients recover quickly from delirium.
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Affiliation(s)
- Jooyoung Oh
- Department of Psychiatry, Gangnam Severance Hospital, Yonsei University Health System, Seoul, South Korea
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, South Korea
| | - Jinsil Ham
- Department of Biomedical Science and Engineering (BMSE), Institute of Integrated Technology (IIT), Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Dongrae Cho
- Department of Biomedical Science and Engineering (BMSE), Institute of Integrated Technology (IIT), Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Jin Young Park
- Department of Psychiatry, Gangnam Severance Hospital, Yonsei University Health System, Seoul, South Korea
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, South Korea
| | - Jae-Jin Kim
- Department of Psychiatry, Gangnam Severance Hospital, Yonsei University Health System, Seoul, South Korea
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, South Korea
| | - Boreom Lee
- Department of Biomedical Science and Engineering (BMSE), Institute of Integrated Technology (IIT), Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
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Bae J, Shin TJ, Kim S, Choi DH, Cho D, Ham J, Manca M, Jeong S, Lee B, Kim JG. The changes of cerebral hemodynamics during ketamine induced anesthesia in a rat model. J Biophotonics 2018; 11:e201800081. [PMID: 29799675 DOI: 10.1002/jbio.201800081] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 05/24/2018] [Indexed: 06/08/2023]
Abstract
Current electroencephalogram (EEG) based-consciousness monitoring technique is vulnerable to specific clinical conditions (eg, epilepsy and dementia). However, hemodynamics is the most fundamental and well-preserved parameter to evaluate, even under severe clinical situations. In this study, we applied near-infrared spectroscopy (NIRS) system to monitor hemodynamic change during ketamine-induced anesthesia to find its correlation with the level of consciousness. Oxy-hemoglobin (OHb) and deoxy-hemoglobin concentration levels were continuously acquired throughout the experiment, and the reflectance ratio between 730 and 850 nm was calculated to quantify the hemodynamic changes. The results showed double peaks of OHb concentration change during ketamine anesthesia, which seems to be closely related to the consciousness state of the rat. This finding suggests the possibility of NIRS based-hemodynamic monitoring as a supplementary parameter for consciousness monitoring, compensating drawbacks of EEG signal based monitoring.
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Affiliation(s)
- Jayyoung Bae
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Teo J Shin
- Department of Pediatric Dentistry, School of Dentistry, Seoul National University, Seoul, South Korea
| | - Seonghyun Kim
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Dong-Hyuk Choi
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Dongrae Cho
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Jinsil Ham
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Marco Manca
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
| | - Seongwook Jeong
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, South Korea
| | - Boreom Lee
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Jae G Kim
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
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Ham J, Meerten E, Fiets E, Jeurissen Mc Haaglanden F, Slingerland M, van der Graaf W, van Herpen C, Beerepoot L. Cetuximab in combination with methotrexate (MTX) as first-line treatment in recurrent or metastatic (R/M) squamous cell carcinoma of the head and neck (SCCHN): A phase Ib randomized phase II study versus single agent MTX. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy287.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Song K, Lochmann T, Patel N, Ham J, Windle B, Harada H, Leverson J, Souers A, Ebi H, Faber A. PS06.02 Drug-Tolerant EGFR Mutant Lung Cancer Cells Rely on MCL-1 Translation and are Eliminated by MCL-1 Inhibitors. J Thorac Oncol 2017. [DOI: 10.1016/j.jtho.2017.09.083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Cho D, Ham J, Oh J, Park J, Kim S, Lee NK, Lee B. Detection of Stress Levels from Biosignals Measured in Virtual Reality Environments Using a Kernel-Based Extreme Learning Machine. Sensors (Basel) 2017; 17:s17102435. [PMID: 29064457 PMCID: PMC5677291 DOI: 10.3390/s17102435] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 10/20/2017] [Accepted: 10/20/2017] [Indexed: 02/07/2023]
Abstract
Virtual reality (VR) is a computer technique that creates an artificial environment composed of realistic images, sounds, and other sensations. Many researchers have used VR devices to generate various stimuli, and have utilized them to perform experiments or to provide treatment. In this study, the participants performed mental tasks using a VR device while physiological signals were measured: a photoplethysmogram (PPG), electrodermal activity (EDA), and skin temperature (SKT). In general, stress is an important factor that can influence the autonomic nervous system (ANS). Heart-rate variability (HRV) is known to be related to ANS activity, so we used an HRV derived from the PPG peak interval. In addition, the peak characteristics of the skin conductance (SC) from EDA and SKT variation can also reflect ANS activity; we utilized them as well. Then, we applied a kernel-based extreme-learning machine (K-ELM) to correctly classify the stress levels induced by the VR task to reflect five different levels of stress situations: baseline, mild stress, moderate stress, severe stress, and recovery. Twelve healthy subjects voluntarily participated in the study. Three physiological signals were measured in stress environment generated by VR device. As a result, the average classification accuracy was over 95% using K-ELM and the integrated feature (IT = HRV + SC + SKT). In addition, the proposed algorithm can embed a microcontroller chip since K-ELM algorithm have very short computation time. Therefore, a compact wearable device classifying stress levels using physiological signals can be developed.
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Affiliation(s)
- Dongrae Cho
- Department of Biomedical Science and Engineering (BMSE), Institute of Integrated Technology (IIT), Gwangju Institute of Science and Technology, Gwangju 61005, Korea.
| | - Jinsil Ham
- Department of Biomedical Science and Engineering (BMSE), Institute of Integrated Technology (IIT), Gwangju Institute of Science and Technology, Gwangju 61005, Korea.
| | - Jooyoung Oh
- Department of Biomedical Science and Engineering (BMSE), Institute of Integrated Technology (IIT), Gwangju Institute of Science and Technology, Gwangju 61005, Korea.
| | - Jeanho Park
- Research Institute of Industrial Technology Convergence, Korea Institute of Industrial Technology, Ansan 15588, Korea.
| | - Sayup Kim
- Research Institute of Industrial Technology Convergence, Korea Institute of Industrial Technology, Ansan 15588, Korea.
| | - Nak-Kyu Lee
- Research Institute of Industrial Technology Convergence, Korea Institute of Industrial Technology, Ansan 15588, Korea.
| | - Boreom Lee
- Department of Biomedical Science and Engineering (BMSE), Institute of Integrated Technology (IIT), Gwangju Institute of Science and Technology, Gwangju 61005, Korea.
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Cho D, Shin TJ, Ham J, Choi DH, Kim S, Jeong S, Kim HI, Kim JG, Lee B. Differential modulation of thalamo-parietal interactions by varying depths of isoflurane anesthesia. PLoS One 2017; 12:e0175191. [PMID: 28384227 PMCID: PMC5383263 DOI: 10.1371/journal.pone.0175191] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 03/22/2017] [Indexed: 12/03/2022] Open
Abstract
The thalamus is thought to relay peripheral sensory information to the somatosensory cortex in the parietal lobe. Long-range thalamo-parietal interactions play an important role in inducing the effect of anesthetic. However, whether these interaction changes vary with different levels of anesthesia is not known. In the present study, we investigated the influence of different levels of isoflurane-induced anesthesia on the functional connectivity between the thalamus and the parietal region. Microelectrodes were implanted in rats to record local field potentials (LFPs). The rats underwent different levels of isoflurane anesthesia [deep anesthesia: isoflurane (ISO) 2.5 vol%, light anesthesia (ISO 1 vol%), awake, and recovery state] and LFPs were recorded from four different brain areas (left parietal, right parietal, left thalamus, and right thalamus). Partial directed coherence (PDC) was calculated for these areas. With increasing depth of anesthesia, the PDC in the thalamus-to-parietal direction was significantly increased mainly in the high frequency ranges; however, in the parietal-to-thalamus direction, the increase was mainly in the low frequency band. For both directions, the PDC changes were prominent in the alpha frequency band. Functional interactions between the thalamus and parietal area are augmented proportionally to the anesthesia level. This relationship may pave the way for better understanding of the neural processing of sensory inputs from the periphery under different levels of anesthesia.
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Affiliation(s)
- Dongrae Cho
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology, Gwangju, South Korea
| | - Teo Jeon Shin
- Department of Pediatric Dentistry and Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Korea
| | - Jinsil Ham
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology, Gwangju, South Korea
| | - Dong-Hyuk Choi
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology, Gwangju, South Korea
| | - Seonghyun Kim
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology, Gwangju, South Korea
| | - Seongwook Jeong
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, South Korea
| | - Hyoung-Ihl Kim
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology, Gwangju, South Korea
| | - Jae Gwan Kim
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology, Gwangju, South Korea
- * E-mail: (BL); (JGK)
| | - Boreom Lee
- Department of Biomedical Science and Engineering, Institute of Integrated Technology, Gwangju Institute of Science and Technology, Gwangju, South Korea
- * E-mail: (BL); (JGK)
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Pasquariello M, Ham J, Burt C, Jahier J, Paillard S, Uauy C, Nicholson P. The eyespot resistance genes Pch1 and Pch2 of wheat are not homoeoloci. Theor Appl Genet 2017; 130:91-107. [PMID: 27665367 PMCID: PMC5214848 DOI: 10.1007/s00122-016-2796-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 09/15/2016] [Indexed: 05/07/2023]
Abstract
KEY MESSAGE Phenotyping and mapping data reveal that chromosome intervals containing eyespot resistance genes Pch1 and Pch2 on 7D and 7A, respectively, do not overlap, and thus, these genes are not homoeloci. Eyespot is a stem-base fungal disease of cereals growing in temperate regions. Two main resistances are currently available for use in wheat. Pch1 is a potent single major gene transferred to wheat from Aegilops ventricosa and located on the distal end of chromosome 7D. Pch2, a moderate resistance deriving from Cappelle Desprez, is located at the end of 7AL. The relative positions of Pch1 and Pch2 on 7D and 7A, respectively, suggest that they are homoeoloci. A single seed decent recombinant F7 population was used to refine the position of Pch2 on 7A. New markers designed to 7D also allowed the position of Pch1 to be further defined. We exploited the syntenic relationship between Brachypodium distachyon and wheat to develop 7A and 7D specific KASP markers tagging inter-varietal and interspecific SNPs and allow the comparison of the relative positions of Pch1 and Pch2 on 7D and 7A. Together, phenotyping and mapping data reveal that the intervals containing Pch1 and Pch2 do not overlap, and thus, they cannot be considered homoeloci. Using this information, we analysed two durum wheat lines carrying Pch1 on 7A to determine whether the Ae.ventricosa introgression extended into the region associated with Pch2. This identified that the introgression is distal to Pch2 on 7A, providing further evidence that the genes are not homoeoloci. However, it is feasible to use this material to pyramid Pch1 and Pch2 on 7A in a tetraploid background and also to increase the copy number of Pch1 in combination with Pch2 in a hexaploid background.
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Affiliation(s)
- M Pasquariello
- John Innes Centre, Norwich Research Park, Colney, Norwich, NR4 7UH, UK
| | - J Ham
- John Innes Centre, Norwich Research Park, Colney, Norwich, NR4 7UH, UK
| | - C Burt
- RAGT Seeds, Grange Road, Ickleton, Essex, CB10 1TA, UK
| | - J Jahier
- IGEPP, Institute for Genetics, Environment and Plant Protection, INRA, La Motte au Vicomte, 35650, Le Rheu, France
| | - S Paillard
- IGEPP, Institute for Genetics, Environment and Plant Protection, INRA, La Motte au Vicomte, 35650, Le Rheu, France
| | - C Uauy
- John Innes Centre, Norwich Research Park, Colney, Norwich, NR4 7UH, UK
| | - P Nicholson
- John Innes Centre, Norwich Research Park, Colney, Norwich, NR4 7UH, UK.
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Choi DH, Shin TJ, Kim S, Bae J, Cho D, Ham J, Park JY, Kim HI, Jeong S, Lee B, Kim JG. Monitoring cerebral oxygenation and local field potential with a variation of isoflurane concentration in a rat model. Biomed Opt Express 2016; 7:4114-4124. [PMID: 27867719 PMCID: PMC5102553 DOI: 10.1364/boe.7.004114] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/25/2016] [Accepted: 09/09/2016] [Indexed: 06/06/2023]
Abstract
We aimed to investigate experimentally how anesthetic levels affect cerebral metabolism measured by near-infrared spectroscopy (NIRS) and to identify a robust marker among NIRS parameters to discriminate various stages of anesthetic depth in rats under isoflurane anesthesia. In order to record the hemodynamic changes and local field potential (LFP) in the brain, fiber-optic cannulae and custom-made microelectrodes were implanted in the frontal cortex of the skull. The NIRS and LFP signals were continuously monitored before, during and after isoflurane anesthesia. As isoflurane concentration is reduced, the level of oxyhemoglobin and total hemoglobin concentrations of the frontal cortex decreased gradually, while deoxyhemoglobin increased. The reflectance ratio between 730nm and 850nm and burst suppression ratio (BSR) correspond similarly with the change of oxyhemoglobin during the variation of isoflurane concentration. These results suggest that NIRS signals in addition to EEG may provide a possibility of developing a new anesthetic depth index.
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Affiliation(s)
- Dong-Hyuk Choi
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea; These authors contributed equally to this study
| | - Teo Jeon Shin
- Department of Pediatric Dentistry, School of Dentistry, Seoul National University, Seoul 03080, South Korea; These authors contributed equally to this study
| | - Seonghyun Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Jayyoung Bae
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Dongrae Cho
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Jinsil Ham
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Ji-Young Park
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Hyoung-Ihl Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Seongwook Jeong
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju 61469, South Korea
| | - Boreom Lee
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea;
| | - Jae Gwan Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea;
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Shin TJ, Cho D, Ham J, Choi DH, Kim S, Jeong S, Kim HI, Kim JG, Lee B. Changes in thalamo-frontal interaction under different levels of anesthesia in rats. Neurosci Lett 2016; 627:18-23. [PMID: 27230989 DOI: 10.1016/j.neulet.2016.05.045] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Revised: 05/10/2016] [Accepted: 05/22/2016] [Indexed: 10/21/2022]
Abstract
Anesthesia is thought to be mediated by inhibiting the integration of information between different areas of the brain. Long-range thalamo-cortical interaction plays a critical role in inducing anesthesia-related unconsciousness. However, it remains unclear how this interaction change according to anesthetic depth. In this study, we aimed to investigate how different levels of anesthesia affect thalamo-frontal interactions. Prior to the experiment, electrodes were implanted to record local field potentials (LFPs). Isoflurane (ISO) was administered and LFPs were measured in rats from four different brain areas (left frontal, right frontal, left thalamus and right thalamus) at four different anesthesia levels: awake, deep (ISO 2.5vol%), light (ISO 1vol%) and recovery. Spectral granger causality (Spectral-GC) were calculated at the measured areas in accordance with anesthetic levels. Anesthesia led to a decrease in connectivity in the thalamo-frontal direction and an increase in connectivity in the frontal-thalamic direction. The changes in thalamo-frontal functional connectivity were prominent during deep anesthesia at high frequency bands. The connection strengths between the thalamus and the frontal area changed depending on the depth of anesthesia. The relationships between anesthetic levels and thalamo-frontal activity may shed light on the neural mechanism by which different levels of anesthesia act.
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Affiliation(s)
- Teo Jeon Shin
- Department of Pediatric Dentistry and Dental Research Institute, School of Dentistry, Seoul National University, Seoul, South Korea
| | - Dongrae Cho
- Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea
| | - Jinsil Ham
- Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea
| | - Dong-Hyuk Choi
- Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea
| | - Seonghyun Kim
- Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea
| | - Seongwook Jeong
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, South Korea
| | - Hyoung-Ihl Kim
- Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea
| | - Jae Gwan Kim
- Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea.
| | - Boreom Lee
- Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea.
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Kristiansen M, Ham J. Programmed cell death during neuronal development: the sympathetic neuron model. Cell Death Differ 2014; 21:1025-35. [PMID: 24769728 PMCID: PMC4207485 DOI: 10.1038/cdd.2014.47] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 03/05/2014] [Accepted: 03/13/2014] [Indexed: 01/08/2023] Open
Abstract
Developing sympathetic neurons of the superior cervical ganglion are one of the best studied models of neuronal apoptosis. These cells require nerve growth factor (NGF) for survival at the time that they innervate their final target tissues during late embryonic and early postnatal development. In the absence of NGF, developing sympathetic neurons die by apoptosis in a transcription-dependent manner. Molecular studies of sympathetic neuron apoptosis began in the 1980s. We now know that NGF withdrawal activates the mitochondrial (intrinsic) pathway of apoptosis in sympathetic neurons cultured in vitro, and the roles of caspases, Bcl-2 (B-cell CLL/lymphoma 2) family proteins and XIAP (X-linked inhibitor of apoptosis protein) have been extensively studied. Importantly, a considerable amount has also been learned about the intracellular signalling pathways and transcription factors that regulate programmed cell death in sympathetic neurons. In this article, we review the key papers published in the past few years, covering all aspects of apoptosis regulation in sympathetic neurons and focusing, in particular, on how signalling pathways and transcription factors regulate the cell death programme. We make some comparisons with other models of neuronal apoptosis and describe possible future directions for the field.
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Affiliation(s)
- M Kristiansen
- Molecular Haematology and Cancer Biology Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
| | - J Ham
- Molecular Haematology and Cancer Biology Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
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Ham J, Midden CJH. A Persuasive Robot to Stimulate Energy Conservation: The Influence of Positive and Negative Social Feedback and Task Similarity on Energy-Consumption Behavior. Int J Soc Robot 2013. [DOI: 10.1007/s12369-013-0205-z] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Song M, Park SH, Ham J, Yang H. 3.216 MNP125EA PROTECTS THE DIFFERENTIATED SH-SY5Y CELLS AGAINST MPP+ TOXICITY IN PART BY DOWNREGULATION OF CASP3 EXPRESSION. Parkinsonism Relat Disord 2012. [DOI: 10.1016/s1353-8020(11)70889-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Kalhan A, Gharibi B, Vazquez M, Jasani B, Neal J, Kidd M, Modlin IM, Pfragner R, Rees DA, Ham J. Adenosine A2A and A2B receptor expression in neuroendocrine tumours: potential targets for therapy. Purinergic Signal 2011; 8:265-74. [PMID: 22119961 DOI: 10.1007/s11302-011-9280-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 11/04/2011] [Indexed: 12/26/2022] Open
Abstract
The clinical management of neuroendocrine tumours is complex. Such tumours are highly vascular suggesting tumour-related angiogenesis. Adenosine, released during cellular stress, damage and hypoxia, is a major regulator of angiogenesis. Herein, we describe the expression and function of adenosine receptors (A(1), A(2A), A(2B) and A(3)) in neuroendocrine tumours. Expression of adenosine receptors was investigated in archival human neuroendocrine tumour sections and in two human tumour cell lines, BON-1 (pancreatic) and KRJ-I (intestinal). Their function, with respect to growth and chromogranin A secretion was carried out in vitro. Immunocytochemical data showed that A(2A) and A(2B) receptors were strongly expressed in 15/15 and 13/18 archival tumour sections. Staining for A(1) (4/18) and A(3) (6/18) receptors was either very weak or absent. In vitro data showed that adenosine stimulated a three- to fourfold increase in cAMP levels in BON-1 and KRJ-1 cells. The non-selective adenosine receptor agonist (adenosine-5'N-ethylcarboxamide, NECA) and the A(2A)R agonist (CGS21680) stimulated cell proliferation by up to 20-40% which was attenuated by A(2B) (PSB603 and MRS1754) and A(2A) (SCH442416) receptor selective antagonists but not by the A(1) receptor antagonist (PSB36). Adenosine and NECA stimulated a twofold increase in chromogranin A secretion in BON-1 cells. Our data suggest that neuroendocrine tumours predominantly express A(2A) and A(2B) adenosine receptors; their activation leads to increased proliferation and secretion of chromogranin A. Targeting adenosine signal pathways, specifically inhibition of A(2) receptors, may thus be a useful addition to the therapeutic management of neuroendocrine tumours.
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Affiliation(s)
- A Kalhan
- Centre for Endocrine and Diabetes Sciences, School of Medicine, Cardiff University, Heath Park, Cardiff, UK
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Sood A, Salih S, Roh D, Lacharme-Lora L, Parry M, Hardiman B, Keehan R, Grummer R, Winterhager E, Gokhale PJ, Andrews PW, Abbott C, Forbes K, Westwood M, Aplin JD, Ingham E, Papageorgiou I, Berry M, Liu J, Dick AD, Garland RJ, Williams N, Singh R, Simon AK, Lewis M, Ham J, Roger L, Baird DM, Crompton LA, Caldwell MA, Swalwell H, Birch-Machin M, Lopez-Castejon G, Randall A, Lin H, Suleiman MS, Evans WH, Newson R, Case CP. Signalling of DNA damage and cytokines across cell barriers exposed to nanoparticles depends on barrier thickness. Nat Nanotechnol 2011; 6:824-833. [PMID: 22056725 DOI: 10.1038/nnano.2011.188] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 09/28/2011] [Indexed: 05/28/2023]
Abstract
The use of nanoparticles in medicine is ever increasing, and it is important to understand their targeted and non-targeted effects. We have previously shown that nanoparticles can cause DNA damage to cells cultured below a cellular barrier without crossing this barrier. Here, we show that this indirect DNA damage depends on the thickness of the cellular barrier, and it is mediated by signalling through gap junction proteins following the generation of mitochondrial free radicals. Indirect damage was seen across both trophoblast and corneal barriers. Signalling, including cytokine release, occurred only across bilayer and multilayer barriers, but not across monolayer barriers. Indirect toxicity was also observed in mice and using ex vivo explants of the human placenta. If the importance of barrier thickness in signalling is a general feature for all types of barriers, our results may offer a principle with which to limit the adverse effects of nanoparticle exposure and offer new therapeutic approaches.
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Affiliation(s)
- A Sood
- Bristol Musculoskeletal Research Unit, Clinical Science at North Bristol University of Bristol, Avon Orthopaedic Centre, Southmead Hospital, Bristol
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Abstract
BACKGROUND Adenosine mediates its actions through four G protein-coupled receptors, A1, A2a, A2b and A3. The A1 receptor (A1R) is dominant in adipocytes where it mediates many actions that include inhibition of lipolysis, stimulation of leptin secretion and protection against obesity-related insulin resistance. OBJECTIVE The objective of this study is to investigate whether induced expression of A1Rs stimulates adipogenesis, or whether A1R expression is a consequence of cells having an adipocyte phenotype. METHODOLOGY Human A1R and A2b receptors (A2bRs) were stably transfected into a murine osteoblast precursor cell line, 7F2. Adipogenesis was determined by lipid accumulation and expression of adipocyte and osteoblast marker molecules. Adenosine receptor expression and activation of associated signal molecules were also evaluated as 7F2 cells were induced to differentiate to adipocytes. RESULTS 7F2 cells transfected with the A1R showed increased adipocyte marker mRNA expression; lipoprotein lipase and glycerol-3-phosphate dehydrogenase were both upregulated, whereas the osteoblast marker alkaline phosphatase (ALP) was downregulated. When cultured in adipocyte differentiating media, such cells also showed increased adipogenesis as judged by lipid accumulation. Conversely, A2bR transfection stimulated osteocalcin and ALP expression, and in addition, adipogenesis was inhibited in the presence of adipocyte differentiation media. Adipogenic differentiation of naive 7F2 cells also resulted in increased expression of the A1R and reduced or modified expression of the A2a and A2bR. The loss of A2 receptors after adipogenic differentiation was accompanied by a loss of cyclic adenosine monophosphate and ERK1/2 signalling. CONCLUSION These data show that expression of A1Rs induced adipocyte differentiation, whereas A2bR expression inhibited adipogenesis and stimulated an osteoblastic phenotype. These data suggest that targeting A1 and A2bR could be considered in the management of obesity and diabetes. Targeting adenosine signal pathways may be useful in treatment strategies for diseases in which there is an imbalance between osteoblasts and adipocytes.
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Affiliation(s)
- B Gharibi
- Centre for Endocrine and Diabetes Sciences, School of Medicine, Cardiff University, Heath Park, Cardiff, UK
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Rayhill S, Schwartz J, Ham J, Carithers R, Lei Y, Bhattacharya R, Liou I, Landis C, Lamaye A, Rakita R, Dick A, Healey P, Halldorson J, Bhakthavatsalam R, Perkins J, Reyes J. The use of hepatitis B core antibody-positive donor livers does not appear to have a deleterious effect on graft survival in liver transplantation for hepatitis C. Transplant Proc 2011; 42:4141-4. [PMID: 21168646 DOI: 10.1016/j.transproceed.2010.09.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Accepted: 09/09/2010] [Indexed: 11/27/2022]
Abstract
INTRODUCTION The use of hepatitis B core antibody-positive donor livers (HBcAb(+)) has steadily increased. According to a recent multivariate analysis of United Network for Organ Sharing (UNOS) data, there was no significant increase in the risk of using these donors. The increased risk among the hepatitis C virus (HCV)-positive subgroup noted in a univariate model disappeared upon multivariate analysis. However, deeper scrutiny may show that HCV-positive recipients may be at increased risk with HBcAb(+) donor livers, as they require simultaneous treatment with two antiviral regimens there may be deleterious interactions between the two viruses. Thus, the issue of HBcAb(+) donors for HCV-positive recipients merits more detailed analysis. METHODS Using UNOS registry data of all liver transplantations performed during the Model for End-Stage Liver Disease era from February 2002 through November 2007, we analyzed graft survival using Kaplan-Meier and Cox regression analyses. RESULTS Of the 12,543 HCV-positive recipients, 2,543 received HBcAb(-) livers and 853 received HBcAb(+) livers. While Kaplan-Meier analysis showed significantly lower graft survival among HCV-negative recipients of HBcAb(+) livers (P = .0001), there was no significant effect on graft survival among the HCV-positive population (P = .2). To detect an early effect in HCV-positive recipients, we examined 1-year graft survival, observing no significant difference (P = .3). To exclude a possible late effect, we examined graft survival in the HCV-positive population conditional upon surviving at least 1 year after transplantation; no significant difference was observed (P = .6). The elimination of potentially confounding codiagnoses, such as hepatitis B virus, alcoholism, acute graft failure, and hepatocellular cancer did not alter the findings. On univariate analysis, the lack of a significant effect persisted among the HCV population. However, the significant effect observed in the univariate model for the HCV-negative population became insignificant when combined with other risk factors in the multivariate model. CONCLUSION The use of HBcAb(+) livers in recipients with HCV did not appear to have a significant impact on graft survival.
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Affiliation(s)
- S Rayhill
- Department of Surgery, University of Washington, Seattle, Washington 98195-6175, USA.
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Hughes R, Kristiansen M, Lassot I, Desagher S, Mantovani R, Ham J. NF-Y is essential for expression of the proapoptotic bim gene in sympathetic neurons. Cell Death Differ 2010; 18:937-47. [PMID: 21164521 DOI: 10.1038/cdd.2010.166] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Neuronal apoptosis has a major role during development and aberrant apoptosis contributes to the pathology of certain neurological conditions. Studies with nerve growth factor (NGF)-dependent sympathetic neurons have provided important insights into the molecular mechanisms of neuronal apoptosis and the signalling pathways that regulate the cell death programme in neurons. The BH3-only protein Bim is a critical mediator of apoptosis in many cell types and in sympathetic neurons is required for NGF withdrawal-induced death. However, regulation of bim expression is complex and remains incompletely understood. We report that a conserved inverted CCAAT box (ICB) in the rat bim promoter is bound by the heterotrimeric transcription factor NF-Y. Interestingly, NF-Y is required for bim promoter activity and its induction following NGF withdrawal. We demonstrate that NF-Y activity is essential for endogenous Bim expression and contributes to NGF withdrawal-induced death. Furthermore, we find that the transcriptional coactivators CBP and p300 interact with NF-Y and FOXO3a and bind to this region of the bim promoter. The amount of CBP/p300 bound to bim increases after NGF deprivation and inhibition of CBP/p300 activity reduces bim induction. Our results indicate that NF-Y cooperates with FOXO3a to recruit CBP/p300 to the bim promoter to form a stable multi-protein/DNA complex that activates bim transcription after survival factor withdrawal.
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Affiliation(s)
- R Hughes
- Molecular Haematology and Cancer Biology Unit, Institute of Child Health, University College London, London, UK
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Keats K, Ham J, Miller T, Siden H. An Outpatient Pediatric Palliative Care Clinic Model to Build Local Capacity: a 4-Year Experience and Outreach Expansion. Paediatr Child Health 2010. [DOI: 10.1093/pch/15.suppl_a.61ab] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Rayhill SC, Scott D, Orloff S, Horn JL, Schwartz J, Zaman A, Sasaki A, Naugler WS, Chang M, Gaumond J, Wu Y, Ham J. Orthotopic, but reversed implantation of the liver allograft in situs inversus totalis-a simple new approach to a difficult problem. Am J Transplant 2009; 9:1602-6. [PMID: 19459787 PMCID: PMC6658180 DOI: 10.1111/j.1600-6143.2009.02676.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Situs inversus totalis is a rare congenital anomaly in which the heart and abdominal organs are oriented in a mirror image of normal. It provides a unique challenge as there is no established technique for liver transplantation in these patients. Employing two major alterations from our standard technique, a liver was transplanted in the left subphrenic space of a patient with situs inversus totalis. First, the liver was flipped 180 degrees from right to left (facing backward). Second, a reversed cavaplasty (anterior, not posterior, donor suprahepatic caval incision) was performed. Otherwise, it was standard, with end-to-end anastomoses of the portal vein, hepatic artery and bile duct. Three years after the entirely uneventful transplant, the recipient continues to enjoy the benefits of a normally functioning liver. The described technique prevented torsion, kinking and tension on the anastomosed structures by allowing the liver to sit naturally in an anatomical position in the left hepatic fossa. As it required no special measurements or maneuvers, the technique was easy to execute and required no donor liver size restrictions. This novel technique, with a reversed cavaplasty and a 180 degrees right-to-left flip of the liver into a left-sided hepatic fossa, may be ideal for situs inversus totalis.
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Affiliation(s)
- S. C. Rayhill
- Division of Liver and Pancreas Transplantation, Department of Surgery, OHSU, Portland, OR,Corresponding author: Stephen Corrigan Rayhill,
| | - D. Scott
- Division of Liver and Pancreas Transplantation, Department of Surgery, OHSU, Portland, OR
| | - S. Orloff
- Division of Liver and Pancreas Transplantation, Department of Surgery, OHSU, Portland, OR
| | - J.-L. Horn
- Department of Anesthesiology, OHSU, Portland, OR
| | - J. Schwartz
- Division of Hepatology, Department of Medicine, OHSU, Portland, OR and
| | - A. Zaman
- Division of Hepatology, Department of Medicine, OHSU, Portland, OR and
| | - A. Sasaki
- Division of Hepatology, Department of Medicine, OHSU, Portland, OR and
| | - W. S. Naugler
- Division of Hepatology, Department of Medicine, OHSU, Portland, OR and
| | - M. Chang
- Division of Hepatology, Department of Medicine, OHSU, Portland, OR and
| | - J. Gaumond
- Division of Liver and Pancreas Transplantation, Department of Surgery, OHSU, Portland, OR
| | - Y. Wu
- Division of Transplantation, Department of Surgery, University of Arkansas, Little Rock, AR
| | - J. Ham
- Division of Liver and Pancreas Transplantation, Department of Surgery, OHSU, Portland, OR
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Abstract
Investigations into the role of the adenosine A2b receptor have been enigmatic due to the lack of good selective high affinity agonists and antagonists. Over the last few years several new antagonist compounds, based either on a xanthine or pyrrolpyrimidine (polyheterocyclic) structure have been designed and these have been used to localise A2b receptors in different tissues and to determine their function. Recently, animals harbouring either a loss or an over-expression of the A2b receptor have been created and these suggest an anti-inflammatory role for the receptor. In this short review, we describe how the A2b receptor influences inflammation in different tissues. In the anterior pituitary gland the A2b receptors exist predominantly in folliculostellate cells where it stimulates secretion of IL-6 and VEGF and influences gap-junctional communication via connexin-43. The A2b receptor also mediates the release of pro-inflammatory cytokines from many tissues such as bronchial smooth muscle, intestinal epithelial cells and mast cells. The presence of a HIF-1alpha binding site in the promoter region of the A2b receptor gene shows that it is strongly implicated in hypoxia and angiogenesis. Targeting the A2b receptor may also be useful in combating autoimmune type I diabetes. These findings, together, indicate that the A2b receptor plays a role in inflammation; its precise action, whether pro- or anti-inflammatory however may be cell type dependent. Nevertheless several A2b receptor antagonists are being developed for therapeutic intervention and these are either at the preclinical stage or in phase I clinical trials as is the case for CVT-6883 for asthma.
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Affiliation(s)
- J Ham
- Centre for Endocrine and Diabetes Sciences, School of Medicine, Cardiff University, Heath Park, Cardiff CF14 4XN, UK.
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Santos AE, Duarte CB, Iizuka M, Barsoumian EL, Ham J, Lopes MC, Carvalho AP, Carvalho AL. Excitotoxicity mediated by Ca2+-permeable GluR4-containing AMPA receptors involves the AP-1 transcription factor. Cell Death Differ 2005; 13:652-60. [PMID: 16282983 DOI: 10.1038/sj.cdd.4401785] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Cells preferentially expressing GluR4-containing alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptors are particularly sensitive to excitotoxicity mediated through non-N-methyl-D-aspartate receptors. However, the excitotoxic signalling pathways associated with GluR4-containing AMPA receptors are not known. In this work, we investigated the downstream signals coupled to excitotoxicity mediated by Ca2+-permeable GluR4-containing AMPA receptors, using a HEK 293 cell line constitutively expressing the GluR4flip subunit of AMPA receptors (HEK-GluR4). Glutamate stimulation of GluR4-containing AMPA receptors decreased cell viability, in a calcium-dependent manner, when the receptor desensitisation was prevented with cyclothiazide. The excitotoxic stimulation mediated through GluR4-containing AMPA receptors increased activator protein-1 (AP-1) DNA-binding activity. Inhibition of the AP-1 activity by overexpression of a c-Jun dominant-negative form protected HEK-GluR4 cells against excitotoxic damage. Taken together, the results indicate that overactivation of Ca2+-permeable GluR4-containing AMPA receptors is coupled to a death pathway mediated, at least in part, by the AP-1 transcription factor.
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Affiliation(s)
- A E Santos
- Center for Neuroscience and Cell Biology, Department of Zoology, University of Coimbra, 3004-517 Coimbra, Portugal
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Badiu C, Ham J, Scanlon M, Møller M, Coculescu M. Expression of thyrotropin-releasing hormone messenger RNA in human pituitary adenomas with follicle-stimulating hormone immunoreactivity. Endocr Pract 2005; 5:10-6. [PMID: 15251697 DOI: 10.4158/ep.5.1.10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To assess the correlation between thyrotropin-releasing hormone (TRH) messenger RNA (mRNA) and the immunoreactive type of human pituitary adenomas. METHODS Twenty-eight patients (14 to 73 years old) who had pituitary adenomas (18 nonfunctioning adenomas, 8 growth hormone-secreting adenomas, and 2 prolactinomas) underwent surgical treatment. Pituitaries removed at autopsy from four patients without evidence of pituitary disease were used as controls. Fragments of pituitary adenomas were processed for TRH mRNA by in situ hybridization (radioactive and nonradioactive) and for TRH peptide and anterior pituitary hormones (b-thyrotropin, b-follicle-stimulating hormone [FSH], bluteinizing hormone [LH], prolactin, and growth hormone) by immunohistochemistry with use of the avidinbiotin technique. Quantitative immunohistochemical studies were performed by using image analysis software. The signal was considered positive when more than 5% of the cells were stained. RESULTS Cells expressing TRH mRNA were detected in 22 of 28 pituitary adenomas--15 of 18 nonfunctioning pituitary adenomas, 5 of 8 growth hormone-secreting adenomas, and both prolactinomas. TRH peptide was revealed in only 10 adenomas, all expressing TRH mRNA as well. All but one nonfunctioning adenoma expressing TRH mRNA in more than 5% of the cells were b-FSH immunoreactive (15 of 16 cases; P<0.005, c 2 test), whereas only 6 of 16 nonfunctioning adenomas exhibited both b-thyrotropin and TRH mRNA and only 5 of 16 were positive for both b-LH and TRH mRNA. CONCLUSION These results confirm previous data demonstrating the presence of TRH mRNA and TRH peptide in human pituitary tumor cells. We further showed that the presence of TRH mRNA is significantly correlated with FSH immunoreactive gonadotropinomas. The release of FSH after an intravenous TRH test only in gonadotropinomas, together with local production of TRH, suggests a role for TRH in pathogenesis.
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Affiliation(s)
- C Badiu
- Department of Endocrinology, Carol Davila University of Medicine, and Pharmacy, Bucharest, Romania
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Abstract
Adenosine receptors are widely distributed in most species and mediate a diverse range of physiological and pathological effects. Although adenosine receptors have been identified in the pituitary gland, the distribution of the individual subtypes (A(1), A(2A), A(2B), A(3)) has not been well defined. Furthermore, the effects of adenosine on pituitary trophic activity and function are not well established despite good evidence for growth- and immune-modulating properties of the nucleoside elsewhere. Recent advances have provided a more detailed description of adenosine receptor distribution and function in the anterior pituitary and this commentary reviews these observations and highlights some of the possible implications in relation to the control of the hypothalamic-pituitary-adrenal axis and the regulation of inflammation and pituitary cell growth.
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Affiliation(s)
- D A Rees
- Department of Medicine, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK.
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Rees DA, Lewis MD, Lewis BM, Smith PJ, Scanlon MF, Ham J. Adenosine-regulated cell proliferation in pituitary folliculostellate and endocrine cells: differential roles for the A(1) and A(2B) adenosine receptors. Endocrinology 2002; 143:2427-36. [PMID: 12021208 DOI: 10.1210/endo.143.6.8837] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A(1) and A(2) adenosine receptors have been identified in the pituitary gland, but the cell type(s) on which they are located and their effects on pituitary cell growth are not known. Therefore, we analyzed the expression of A(1) and A(2) receptors in primary rat anterior pituitary cells, two pituitary folliculostellate (TtT/GF and Tpit/F1) and two pituitary endocrine (GH(3) and AtT20) cell lines, and compared their effects on cell proliferation. In anterior pituitary and folliculostellate cells, adenosine and adenosine receptor agonists (5'-N-ethylcarboxamidoadenosine, a universal agonist, and CGS 21680, an A(2A) receptor agonist) stimulated cAMP levels with a rank order of potency that indicates the presence of functional A(2B) receptors. This stimulation, however, was not observed in either GH(3) or AtT20 cells, where adenosine and the A(1) receptor agonist 2-chloro-N(6)-cyclopentyladenosine inhibited VIP/forskolin-stimulated cAMP production. Expression of A(2B) and A(1) receptors in the folliculostellate cells and that of the A(1) receptor in the endocrine cells were confirmed by RT-PCR, immunocytochemistry, and ligand binding. Adenosine and 5'-N-ethylcarboxamidoadenosine dose-dependently (10 nM to 10 microM) stimulated growth in the folliculostellate, but not in the endocrine, cells, whereas in the latter, 100 microM adenosine and 2-chloro-N(6)-cyclopentyladenosine inhibited cell proliferation by slowing cell cycle progression. These data highlight the differential expression of A(1) and A(2B) adenosine receptors in pituitary cells and provide evidence for opposing effects of adenosine on pituitary folliculostellate and endocrine cell growth.
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Affiliation(s)
- D A Rees
- Department of Medicine, University of Wales College of Medicine, Cardiff, United Kingdom CF14 4XN.
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Abstract
Epidermal growth factor (EGF) causes pituitary GH3 cells to change from their normal predominantly rounded morphology to much more elongated cells with extensive filopodia, and this effect is accompanied by a parallel increase in cell volume. In view of this, and because EGF receptor expression is increased in some pituitary tumours, we examined the mechanism of this EGF-induced morphological effect as it may play a role in tumour invasiveness. The effect of treatment of the cells with EGF (1 nm, 4 days) was determined visually (expressed as percent non round cells) and by measuring the cell volume by Coulter Counter analysis. EGF treatment caused the cells to change their morphology with percent non round cells increasing from 37% in control cells to 74% in EGF-treated cultures; this was accompanied by a parallel increase in cell volume. Treatment of the cells with EGF in the presence of the MEK1 inhibitor (PD98059) completely blocked the EGF-induced morphological changes, showing that activation of the mitogen-activated protein kinase (MAPK) pathway is necessary to mediate this effect. Transfection of the cells with a constitutively activated mutant of MEK1 produced a similar morphological change to that produced by EGF treatment, with the proportion of non round cells increasing to 62% with a parallel increase in cell volume compared to cells transfected with the empty vector, demonstrating that direct activation of MAPK pathway is sufficient to mediate the observed morphological effects. The effects produced by activated MEK1 transfection could be blocked by PD98059. EGF had opposing effects on prolactin and growth hormone (GH) secretion by the cells, increasing prolactin release and inhibiting GH release. Transfection of the cells with activated MEK1 produced similar effects on hormone release as EGF treatment. In conclusion, the morphological effects of EGF on GH3 cells are mediated by activation of the MAPK pathway as blockade of this pathway abolished the observed effect, and direct activation of this pathway by transfection with an activated mutant of MEK1 was able to duplicate these effects. This mechanism may contribute to the growth and possibly local invasiveness of some pituitary tumours that express the EGF receptor.
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Affiliation(s)
- M D Lewis
- Section of Endocrinology, Department of Medicine, University of Wales College of Medicine, Heath Park, Cardiff, UK.
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Rees DA, Hepburn PJ, McNicol AM, Francis K, Jasani B, Lewis MD, Farrell WE, Lewis BM, Scanlon MF, Ham J. Loss of ACTH expression in cultured human corticotroph macroadenoma cells is consistent with loss of the POMC gene signal sequence. Mol Cell Endocrinol 2002; 189:51-7. [PMID: 12039064 DOI: 10.1016/s0303-7207(01)00755-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The proopiomelanocortin (POMC) gene is highly expressed in the pituitary gland where the resulting mRNA of 1200 base pairs (bp) gives rise to a full-length protein sequence. In peripheral tissues however both shorter and longer POMC variants have been described, these include for example placental tissue which contain 800 (truncated at the 5' end) and 1500 as well as the 1200 bp transcripts. The importance of the 800 bp transcript is unclear as the lack of a signal sequence renders the molecule to be non-functional. This transcript has not been previously demonstrated in the pituitary gland. In this report we show evidence of a 5' truncated POMC gene in human pituitary corticotroph macroadenoma cells (JE) maintained in primary culture for >1 year. The original tumour tissue and the derived cells during early passage (up to passage 4-5) immunostained for ACTH and in situ hybridisation confirmed the presence of the POMC gene in the cultured cells. These cells also secreted 15-40 pg/10(5) cells/24 h ACTH. In addition, as expected RT-PCR demonstrated the presence of all three POMC gene exons and is thus indicative of a full-length POMC gene. In late culture passages (passages 8-15) JE cells ceased to express ACTH and cell growth became very slow due presumably to cells reaching their Hayflick limit. ACTH immunostaining in these cells was undetectable and ACTH secretion was also at the detection limits of the assay and no greater than 10 pg/10(5) cells/24 h. ACTH precursor molecules were also undetectable. RT-PCR for the POMC gene in these late passage cells showed that only exon 3 was detectable, in contrast to early passage cells where all three exons were present. In summary we isolated in culture, human pituitary cells that possessed initially all three exons of the POMC gene and immunostained for ACTH. On further passaging these cells showed a loss of exons 1 and 2 in the POMC gene and a loss of ACTH immunostaining and secretion. We would like to suggest that the loss of ACTH peptide expression in these late passage cells is in part due to the loss of the POMC signal sequence. An alternative explanation for our findings is that there were originally two populations of corticotrophs in the cultures, one of which possessed the full-length POMC gene and the other only the 5' truncated POMC transcript and it is these latter cells which survived in culture. In either scenario this is the first report of the 5' truncated POMC gene occurring in pituitary cells.
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Affiliation(s)
- D A Rees
- Department of Medicine, University of Wales College of Medicine, Heath Park, CF14 4XN, Cardiff, UK
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Contos MJ, Cales W, Sterling RK, Luketic VA, Shiffman ML, Mills AS, Fisher RA, Ham J, Sanyal AJ. Development of nonalcoholic fatty liver disease after orthotopic liver transplantation for cryptogenic cirrhosis. Liver Transpl 2001; 7:363-73. [PMID: 11303298 DOI: 10.1053/jlts.2001.23011] [Citation(s) in RCA: 307] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Many subjects with cryptogenic cirrhosis have underlying nonalcoholic steatohepatitis (NASH). The natural history of NASH-related cryptogenic cirrhosis after orthotopic liver transplantation (OLT) is not well defined. A primarily retrospective study of patients with the clinical histological phenotype of NASH-related cirrhosis undergoing OLT was performed. Data were compared with 2 sets of age- and weight-matched controls with (1) primary biliary cirrhosis or primary sclerosing cholangitis or (2) alcoholic liver disease. After OLT, all patients were managed by a standard immunosuppressive protocol. Liver biopsies were performed at 6 and 12 months after OLT and at 1- to 2-year intervals thereafter, as well as when liver enzyme levels were elevated enough to warrant diagnostic biopsy. Twenty-seven subjects with cryptogenic cirrhosis and a clinical histological phenotype of NASH and 3 patients with a long-standing diagnosis of NASH before OLT were included. The 30-day perioperative mortality was 1 in 30 patients. During a median follow-up of 3.5 +/- 2.7 years, 2 additional patients died of sepsis. There was a time-dependent increase in the risk for allograft steatosis that approached 100% by 5 years compared with only an approximately 25% incidence of steatosis in the control groups (P <.009, log-rank test). On multivariate analysis, only the cumulative steroid dose correlated with time to development of allograft steatosis. Three patients developed histological progression from hepatic steatosis to steatohepatitis. Of these, 1 patient developed progressive fibrosis. Four patients experienced at least 1 episode of acute cellular rejection; however, no patient developed chronic rejection or graft failure. In conclusion, nonalcoholic fatty liver disease occurs frequently after OLT in patients with the phenotype of NASH-related cirrhosis. Despite the frequent histological recurrence of disease, clinical outcomes are similar to those of other groups of patients undergoing OLT.
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Affiliation(s)
- M J Contos
- Department of Pathology, Division of Gastroenterology/Hepatology/Nutrition, Virginia Commonwealth University-Medical College of Virginia, Richmond, VA, USA
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Whitfield J, Neame SJ, Paquet L, Bernard O, Ham J. Dominant-negative c-Jun promotes neuronal survival by reducing BIM expression and inhibiting mitochondrial cytochrome c release. Neuron 2001; 29:629-43. [PMID: 11301023 DOI: 10.1016/s0896-6273(01)00239-2] [Citation(s) in RCA: 451] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Sympathetic neurons require nerve growth factor for survival and die by apoptosis in its absence. Key steps in the death pathway include c-Jun activation, mitochondrial cytochrome c release, and caspase activation. Here, we show that neurons rescued from NGF withdrawal-induced apoptosis by expression of dominant-negative c-Jun do not release cytochrome c from their mitochondria. Furthermore, we find that the mRNA for BIM(EL), a proapoptotic BCL-2 family member, increases in level after NGF withdrawal and that this is reduced by dominant-negative c-Jun. Finally, overexpression of BIM(EL) in neurons induces cytochrome c redistribution and apoptosis in the presence of NGF, and neurons injected with Bim antisense oligonucleotides or isolated from Bim(-/-) knockout mice die more slowly after NGF withdrawal.
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Affiliation(s)
- J Whitfield
- Eisai London Research Laboratories, Bernard Katz Building, University College London, Gower Street, WC1E 6BT, London, United Kingdom
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Eilers A, Whitfield J, Shah B, Spadoni C, Desmond H, Ham J. Direct inhibition of c-Jun N-terminal kinase in sympathetic neurones prevents c-jun promoter activation and NGF withdrawal-induced death. J Neurochem 2001; 76:1439-54. [PMID: 11238729 DOI: 10.1046/j.1471-4159.2001.00150.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
c-Jun N-terminal kinases (JNKs) regulate gene expression by phosphorylating transcription factors, such as c-Jun. Studies with JNK: knockout mice suggest that JNK activity may be required for excitotoxin-induced apoptosis in the adult hippocampus and for apoptosis in the developing embryonic neural tube. Here we investigate the role of JNKs in classical neurotrophin-regulated developmental neuronal death by using nerve growth factor (NGF)-dependent sympathetic neurones. In this system, NGF withdrawal leads to an increase in JNK activity, an increase in c-Jun protein levels and c-Jun N-terminal phosphorylation before the cell death commitment point, and c-Jun activity is required for cell death. To inhibit JNK activity in sympathetic neurones we have used two different JNK inhibitors that act by distinct mechanisms: the compound SB 203580 and the JNK binding domain (JBD) of JNK interacting protein 1 (JIP-1). We demonstrate that JNK activity is required for c-Jun phosphorylation, c-jun promoter activation and NGF withdrawal-induced apoptosis. We also show that ATF-2, a c-Jun dimerization partner that can regulate c-jun gene expression, is activated following NGF deprivation. Finally, by co-expressing the JBD and a regulatable c-Jun dominant negative mutant we demonstrate that JNK and AP-1 function in the same pro-apoptotic signalling pathway after NGF withdrawal.
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Affiliation(s)
- A Eilers
- Eisai London Research Laboratories, University College London, London, UK
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Cavanaugh JE, Ham J, Hetman M, Poser S, Yan C, Xia Z. Differential regulation of mitogen-activated protein kinases ERK1/2 and ERK5 by neurotrophins, neuronal activity, and cAMP in neurons. J Neurosci 2001; 21:434-43. [PMID: 11160424 PMCID: PMC6763829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Activation of the extracellular signal-regulated kinase 1 (ERK1) and ERK2 by neurotrophins, neuronal activity, or cAMP has been strongly implicated in differentiation, survival, and adaptive responses of neurons during development and in the adult brain. Recently, a new member of the mitogen-activated protein (MAP) kinase family, ERK5, was discovered. Like ERK1 and ERK2, ERK5 is expressed in neurons, and ERK5 stimulation by epidermal growth factor is blocked by the MAP kinase/ERK kinase 1 (MEK1) inhibitors PD98059 and U0126. This suggests the interesting possibility that some of the functions attributed to ERK1/2 may be mediated by ERK5. However, the regulatory properties of ERK5 in primary cultured neurons have not been reported. Here we examined the regulation of ERK5 signaling in primary cultured cortical neurons. Our data demonstrate that, similar to ERK1/2, ERK5 is activated by neurotrophins including brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), and NT-4. BDNF stimulation of ERK5 required the activity of MEK5. Surprisingly, ERK5 was not stimulated by cAMP or neuronal activity induced by glutamate or membrane depolarization. In contrast to ERK1/2, ERK5 strongly activated the transcriptional activity of myocyte enhancer factor 2C (MEF2C) in pheochromocytoma 12 (PC12) cells and was required for neurotrophin stimulation of MEF2C transcription in both PC12 cells and cortical neurons. Furthermore, ERK1/2, but not ERK5, induced transcription from Elk1 and the cAMP/ Ca(2+) response element in PC12 cells. Our data suggest that mechanisms for regulation of ERK5 and downstream transcriptional pathways regulated by ERK5 are distinct from those of ERK1/2 in neurons. Furthermore, ERK5 is the first MAP kinase identified whose activity is stimulated by neurotrophins but not by neuronal activity.
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Affiliation(s)
- J E Cavanaugh
- Departments of Environmental Health and Pharmacology, University of Washington, Seattle, Washington 98195-7234, USA
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Abstract
Critical pathways, developed for utilisation in the health sector, are tools that are increasingly being used toimplement co-ordinated patient care. The introduction of critical pathways results in planned progress throughan episode of care, whilst optimising health outcomes and minimising resource utilisation. The advantages ofimplementing critical pathways are increasingly evident, with reports of increased co-ordination of activities,minimum delays in the provision of care, enhanced interdisciplinary communication, enhancedcommunication with clients, improved discharge planning processes and the implementation of a continuousquality improvement process (Pearson et al, 1995, p941-948).Hospitals in rural areas have not been excluded from the issue of providing quality care whilst containing costs.Distance, sparse population density and decreased resources intensify the need for co-ordinated care systems inrural areas. Co-ordinated care planning to date has centred on metropolitan, acute care hospitals, althoughinterest in the design and implementation of critical pathways has been demonstrated by many health agenciesin rural areas wanting to share in the advantages of implementing critical pathways (Spath, 1999, p45-48;Bertram, 1996 p54-66; Rawskey, 1996, p49-51; Ely, 1995, p66-64).
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Affiliation(s)
- J Ham
- Bendigo Health Care Group, Collaborative Health Education and Research Centre
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Abstract
In the pathogenesis of thyrotropin (TSH) immunopositive pituitary adenomas, trigger mutagenetic events are well recognized. However, the way towards a clinical significant tumor is followed under the pressure of growth factors, among which the intrapituitary synthesis of releasing factors could bring a significant contribution. In this study, the production of thyrotropin releasing hormone (TRH) and beta TSH chain was evaluated at the mRNA level by in situ hybridization and end product level by immunohistochemistry, in 18 patients submitted to neurosurgery for pituitary macroadenomas. The hormonal sampling showed abnormal secretion for FSH in 5 and TSH in 4 patients. Seven cases were immunopositive for TSH, and expressed TSH beta mRNA. All but one out of these expressed also TRH mRNA. FSH immunoreactivity was documented in 12/ 18, only one of these being negative for TRH mRNA. Paracrine TRH could contribute to the pathogenesis of these "mute" adenomas.
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Affiliation(s)
- C Badiu
- Carol Davila University of Medicine and Pharmacy, Department of Endocrinology, PO Box 41-31, 78260 Bucharest, Romania.
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Abstract
There has been considerable interest in the molecular mechanisms of apoptosis in mammalian neurons because this form of neuronal cell death is important for the normal development of the nervous system and because inappropriate neuronal apoptosis may contribute to the pathology of human neurodegenerative diseases. The aim of recent research has been to identify the key components of the cell death machinery in neurons and understand how the cell death programme is regulated by intracellular signalling pathways activated by the binding of neurotrophins or death factors to specific cell surface receptors. The aim of this commentary was to review research that has investigated the role of the Jun N-terminal kinase (JNK)/c-Jun signalling pathway in neuronal apoptosis, focusing in particular on work carried out with developing sympathetic neurons. Experiments with sympathetic neurons cultured in vitro, as well as with cerebellar granule neurons and differentiated PC12 cells, have demonstrated that JNK/c-Jun signalling can promote apoptosis following survival factor withdrawal. In addition, experiments with Jnk(-/-) knockout mice have provided evidence that Jnk3 may be required for apoptosis in the hippocampus in vivo following injection of kainic acid, an excitotoxin, and that Jnk1 and Jnk2 are required for apoptosis in the developing embryonic neural tube. However, in the embryonic forebrain, Jnk1 and Jnk2 have the opposite function and are necessary for the survival of developing cortical neurons. These results suggest that JNKs and c-Jun are important regulators of the cell death programme in the mammalian nervous system, but that their biological effects depend on the neuronal type and stage of development.
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Affiliation(s)
- J Ham
- Cancer Biology and Molecular Haematology Unit, Camelia Botnar Laboratories, Institute of Child Health, University College London, London WC1N 1EH, United Kingdom.
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Crisp M, Starkey KJ, Lane C, Ham J, Ludgate M. Adipogenesis in thyroid eye disease. Invest Ophthalmol Vis Sci 2000; 41:3249-55. [PMID: 11006210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
PURPOSE Adipogenesis contributes to the pathogenesis of thyroid eye disease (TED). Thyrotropin receptor (TSHR) transcripts are present in orbital fat. This study was conducted to determine whether they are expressed as functional protein, and if so, whether this is restricted to TED orbits or to a particular stage in adipocyte differentiation. METHODS Samples of fat were obtained from 18 TED-affected orbits and 4 normal orbits, and 9 were obtained from nonorbital locations. Frozen sections were examined by immunocytochemistry using monoclonal antibodies specific for the human TSHR. Samples were disaggregated and the preadipocytes separated from the mature by differential centrifugation and cultured in serum-free or DM and examined for morphologic changes, oil red O and TSHR staining, and TSH-induced cyclic adenosine monophosphate (cAMP) production. RESULTS Marked immunoreactivity was observed in frozen sections from all three TED samples and faint staining in both normal orbital fat samples. In vitro, 1% to 5% of preadipocytes displayed TSHR immunoreactivity in five of six TED and two of three normal orbital samples and in three of five nonorbital samples. Differentiation, was induced in all 14 orbital samples. Three of four nonorbital samples contained occasional differentiated cells. Fifty percent to 70% of differentiating cells demonstrated receptor immunoreactivity. Two of three TED and four of four nonorbital preadipocytes in DM and/or mature adipocytes displayed a TSH-mediated increase in cAMP. CONCLUSIONS The results indicate that orbital fat TSHR transcripts are expressed as protein, which can be functional. This is not aberrant in TED orbits, although expression may be upregulated. The majority of preadipocytes undergoing differentiation express the receptor, indicating a key role for this population in one mechanism for increasing orbital volume.
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Affiliation(s)
- M Crisp
- Endocrine Section, Department of Medicine, and the. Department of Ophthalmology University of Wales College of Medicine, Cardiff, United Kingdom
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Abstract
BACKGROUND Increasing recognition of the need for training in teaching skills for clinical teachers has coincided with data that registrars and residents conduct much 'on the job' teaching as part of their routine work. While attention has been devoted to training consultants, support for the teaching role of the junior staff has been relatively neglected. The aim of the present report is to describe the teaching experiences of surgical registrars and the impact of a registrar teaching workshop. METHOD A half-day programme combining presentation and discussion of surgical teaching with practical skills sessions was designed for surgical registrars at Prince of Wales Hospital. The programme included observation and feedback of brief teaching simulations at the bedside of volunteer patients to newly commenced clinical students, and small group sessions on clinic and operating theatre teaching. A pre-workshop questionnaire sought information about the registrars' own teaching, and a survey 3 months after the workshop determined if any changes to teaching practice had occurred. RESULTS The registrars were generally moderately to very confident with their teaching ability but more than 75% felt that they were more confident after the workshop. Only three of 39 registrars had received any instruction aimed at improving their teaching skills, yet 34/39 had taught either on the ward, in the clinics or in the operating room. Follow-up after 3 months revealed that most registrars were enjoying their teaching tasks more, and half had increased their teaching since the workshop and began discussing teaching with their surgical colleagues. CONCLUSIONS The present project demonstrates that relatively brief interventions focused on skill development may enhance the confidence and enjoyment of junior clinical teachers and increase the frequency of 'teaching on the run'.
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Affiliation(s)
- P Crowe
- Department of Surgery, Prince of Wales Hospital, Randwick, New South Wales, Australia.
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Eilers A, Whitfield J, Vekrellis K, Neame SJ, Shah B, Ham J. c-Jun and Bax: regulators of programmed cell death in developing neurons. Biochem Soc Trans 1999; 27:790-7. [PMID: 10830103 DOI: 10.1042/bst0270790] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- A Eilers
- Eisai London Research Laboratories, University College London, U.K
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Lallemand D, Ham J, Garbay S, Bakiri L, Traincard F, Jeannequin O, Pfarr CM, Yaniv M. Stress-activated protein kinases are negatively regulated by cell density. EMBO J 1998; 17:5615-26. [PMID: 9755162 PMCID: PMC1170890 DOI: 10.1093/emboj/17.19.5615] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Stimulation by UV irradiation, TNFalpha, as well as PDGF or EGF activates the JNK/SAPK signalling pathway in mouse fibroblasts. This results in the phosphorylation of the N-terminal domain of c-Jun, increasing its transactivation potency. Using an antibody that specifically recognizes c-Jun phosphorylated at Ser63, we show that culture confluency drastically inhibited c-Jun N-terminal phosphorylation due to the inhibition of the JNK/SAPK pathway. Transfection experiments demonstrate that the inhibition occurs at the same level as, or upstream of, the small G-proteins cdc42 and Rac1. In contrast, the classical MAPK pathway was insensitive to confluency. The inhibition of JNK/SAPK activation depended on the integrity of the actin microfilament network. These results were confirmed and extended in monolayer wounding experiments. After PDGF, EGF or UV stimulation, c-Jun was predominantly phosphorylated in cells bordering the wound, which are the cells that move to occupy the wounded area. Thus, modulation of the stress-dependent signal cascade by confluency will restrict c-Jun N-terminal phosphorylation in response to mitogenic or chemotactic agents to cells that border a wounded area.
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Affiliation(s)
- D Lallemand
- Unité des Virus Oncogènes, Unité associée 1644 du Centre National de la Recherche Scientifique, Paris Cedex 15 France
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Ham J, Webster J, Bond JA, Jasani B, Lewis MD, Hepburn PJ, Davies JS, Lewis BM, Thomas DW, Scanlon MF. Immortalized human pituitary cells express glycoprotein alpha-subunit and thyrotropin beta (TSH beta). J Clin Endocrinol Metab 1998; 83:1598-603. [PMID: 9589662 DOI: 10.1210/jcem.83.5.4803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A major problem in the study of human pituitary cells is their lack of proliferative capacity in vitro. To address this issue, we have infected normal human, postmortem pituitary cells in monolayer culture with a temperature-sensitive (tsA58) mutant of SV40 large T antigen. Several epithelial-like colonies were isolated; and one, designated CHP2, has been studied in detail to identify its functional characteristics. CHP2 cells have undergone more than 150 culture passages and retain an epithelial morphology. They exhibit tight temperature-dependent growth, in the presence and absence of serum, with cell division at 33 C and growth inhibition at 39 C. CHP2 cells, at both temperatures, showed diffuse immunostaining for human alpha-subunit and focal staining for TSH beta. Gene expression was confirmed by RT-PCR and sequencing. TRH and GnRH receptors were not detectable, and their absence was confirmed by their lack of effects on intracellular calcium and inositol phospholipids. Cytogenetic analysis showed that the cells had a modal peak in the diploid range and a smaller peak in the tetraploid range. There was also a consistent loss of chromosome 22 and a normal chromosome 2 homologue, the latter being replaced by one of two chromosome 2 markers, M2A or M2B. In conclusion, we have immortalized human pituitary cells using SV40 tsT, from which we have cloned a cell line expressing alpha-subunit and TSH beta.
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Affiliation(s)
- J Ham
- Department of Medicine, University of Wales College of Medicine, Cardiff, United Kingdom
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47
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Abstract
We investigated the role of hypothalamic glutamate receptors in mediating the stimulatory effect of low glucose (< 5 mM) on somatostatin release. We also studied whether alteration in glutamate release might contribute to the reduced hypothalamic somatostatin response to low glucose observed in diabetic (Goto-Kakizaki) rat hypothalami. Hypothalamic somatostatin release in response to incubation with 1 mM D-glucose was inhibited by the ionotropic glutamate receptor antagonists MK801, D-AP5 and DNQX but not by the metabotropic antagonists L-AP3 or MCPG. The release of somatostatin was increased by the ionotropic agonists NMDA, AMPA and kainate but not by metabotropic agonists t-ACPD or L-AP4. Basal and peak glutamate release in response to incubation with 1 mM glucose, were significantly lower from GK hypothalami There were no significant differences in the basal or stimulated release of serine and GABA. These data indicate that ionotropic NMDA/AMPA/kainate receptors and not metabotropic receptors mediate the effects of glucose on rat hypothalamic somatostatin release. Reduced hypothalamic somatostatin release in response to low glucose in diabetic (Goto-Kakizaki) rats may well be secondary, at least in part, to reduced glutamate release.
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Affiliation(s)
- B G Issa
- Department of Medicine, University of Wales College of Medicine, Cardiff, UK
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48
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Eilers A, Whitfield J, Babij C, Rubin LL, Ham J. Role of the Jun kinase pathway in the regulation of c-Jun expression and apoptosis in sympathetic neurons. J Neurosci 1998; 18:1713-24. [PMID: 9464996 PMCID: PMC6792616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
When deprived of nerve growth factor (NGF), developing sympathetic neurons die by apoptosis. This death is associated with an increase in the level of c-Jun protein and is blocked by expression of a c-Jun dominant negative mutant. Here we have investigated whether NGF withdrawal activates Jun kinases, a family of stress-activated protein kinases that can stimulate the transcriptional activity of c-Jun by phosphorylating serines 63 and 73 in the transactivation domain and which can activate c-jun gene expression. We found that sympathetic neurons contained high basal levels of Jun kinase activity that increased further after NGF deprivation. In contrast, p38 kinase, another stress-activated protein kinase that can also stimulate c-jun gene expression, was not activated after NGF withdrawal. Consistent with Jun kinase activation, we found using a phospho-c-Jun-specific antibody that c-Jun was phosphorylated on serine 63 after NGF withdrawal. Furthermore, expression of a constitutively active form of MEK kinase 1 (MEKK1), which strongly activates the Jun kinase pathway, increased c-Jun protein levels and c-Jun phosphorylation and induced apoptosis in the presence of NGF. This death could be prevented by co-expression of SEKAL, a dominant negative mutant of SAPK/ERK kinase 1 (SEK1), an activator of Jun kinase that is a target of MEKK1. In contrast, expression of SEKAL alone did not prevent c-Jun expression, increases in c-Jun phosphorylation, or cell death after NGF withdrawal. Thus, activation of Jun kinase and increases in c-Jun phosphorylation and c-Jun protein levels occur at the same time after NGF withdrawal, but c-Jun levels and phosphorylation are regulated by an SEK1-independent pathway.
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Affiliation(s)
- A Eilers
- Eisai London Research Laboratories, University College London, London WC1E 6BT, United Kingdom
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Kimball P, Rhodes C, King A, Fisher R, Ham J, Posner M. Flow cross-matching identifies patients at risk for postoperative elaboration of cytotoxic antibodies. Transplantation 1998; 65:444-6. [PMID: 9484770 DOI: 10.1097/00007890-199802150-00029] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Cytotoxic IgG against class I antigens can contribute to renal dysfunction or failure after transplantation. However, the clinical relevance of IgG measured by flow cytometric cross-matching is controversial. This study correlated pre- and postoperative flow reactivity with clinical outcome among renal transplant patients with negative preoperative cytotoxic cross-matches. METHODS Nonsensitized primary renal allograft patients (n = 157) with negative preoperative cytotoxic cross-matches (complement-dependent lymphocytotoxicity assays) were stratified on the basis of IgG reactivity measured by flow cytometric cross-matching (FCXM) as FCXM negative (Neg) or positive against class I (T-pos FCXM) or class II (B-pos FCXM) antigens. The groups were compared in terms of frequency of early rejection and 1-year graft survival. RESULTS Patient distribution was 67% Neg, 14% T-pos FCXM, 14% B-pos FCXM, and 5% IgM FCXM. The incidence of early rejection was 25+/-3% for Neg and 51+/-3% for T- and B-pos FCXM (P < 0.05). One-year graft survival for Neg versus T-pos and B-pos FCXM was 97+/-3% versus 44+/-10% (P < 0.05) and 77+/-5% (P = 0.06), respectively. Rejections requiring plasmapheresis were found only among patients with T-pos FCXM. Among 29 patients, FCXM and complement-dependent lymphocytotoxicity assays were performed 10+/-2 and 28+/-4 days after transplantation. Pre- and posttransplant antibody levels were relatively unchanged among Neg and B-pos FCXM patient groups. In contrast, patients with T-pos FCXM produced cytotoxic IgG against class I after transplantation, which may have contributed to the severe graft dysfunction experienced by this group. CONCLUSIONS FCXM is a useful tool to stratify primary renal transplant candidates in terms of potential risk for severe rejection. Furthermore, demonstration of preoperative flow reactivity against class I may identify a subgroup of patients at risk for early elaboration of cytotoxic alloantibody.
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Affiliation(s)
- P Kimball
- Department of Surgery, Medical College of Virignia, Richmond 23298, USA
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Watson A, Eilers A, Lallemand D, Kyriakis J, Rubin LL, Ham J. Phosphorylation of c-Jun is necessary for apoptosis induced by survival signal withdrawal in cerebellar granule neurons. J Neurosci 1998; 18:751-62. [PMID: 9425017 PMCID: PMC6792526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Cerebellar granule neurons die by apoptosis when deprived of survival signals. This death can be blocked by inhibitors of transcription or protein synthesis, suggesting that new gene expression is required. Here we show that c-jun mRNA and protein levels increase rapidly after survival signal withdrawal and that transfection of the neurons with an expression vector for a c-Jun dominant negative mutant protects them against apoptosis. Phosphorylation of serines 63 and 73 in the c-Jun transactivation domain is known to increase c-Jun activity. By using an antibody specific for c-Jun phosphorylated on serine 63, we show that this site is phosphorylated soon after survival signal withdrawal. To determine whether c-Jun phosphorylation is necessary for apoptosis, we have expressed c-Jun phosphorylation site mutants in granule neurons. c-Junasp, a constitutively active c-Jun mutant in which the known and potential serine and threonine phosphoacceptor sites in the transactivation domain have been mutated to aspartic acid, induces apoptosis under all conditions tested. In contrast, c-Junala, which cannot be phosphorylated because the same sites have been mutated to alanine, blocks apoptosis caused by survival signal withdrawal. Finally, we show that cerebellar granule neurons contain high levels of Jun kinase activity and low levels of p38 kinase activity, neither of which increases after survival signal withdrawal. Mitogen-activated protein kinase activity decreases under the same conditions. These results suggest that c-Jun levels and c-Jun phosphorylation may be regulated by novel mechanisms in cerebellar granule neurons.
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Affiliation(s)
- A Watson
- Eisai London Research Laboratories, University College London, London WC1E 6BT, United Kingdom
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