1
|
Lou L, Du SX, Fu YT, Shao QQ, Guo WL, Zong YP, Qin MM, Tian XX, Li YH. [Acidophil stem cell pituitary neuroendocrine tumors/adenoma: a clinicopathological analysis of five cases]. Zhonghua Bing Li Xue Za Zhi 2024; 53:446-451. [PMID: 38678324 DOI: 10.3760/cma.j.cn112151-20231019-00275] [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] [Subscribe] [Scholar Register] [Indexed: 04/29/2024]
Abstract
Objective: To investigate the clinicopathological characteristics of acidophil stem cell pituitary neuroendocrine tumors (PitNET)/adenoma. Methods: Five cases of acidophil stem cell PitNET/adenoma were diagnosed between May 2022 and July 2023 at the Second Hospital of Hebei Medical University, Shijiazhuang, China. The clinicopathological features of the tumor were analyzed by using histology, immunohistochemistry, and electron microscopy. The relevant literature was reviewed. Results: There were 1 male and 4 females, aged from 23 to 69 years. Patient 3 was 55 years old at the time of diagnosis and first surgery, and relapsed 5 years later. The patients' median age was 32 years. Patients 1 and 5 showed elevated blood prolactin, with various degrees of hormonal symptoms except Patient 3, who showed only tumor compression symptoms. Imaging studies showed that all cases involved the sellar floor. The tumors of Patients 1, 2 and 5 were closely related to the cavernous sinus segment of the internal carotid artery. The tumors exhibited a diffuse growth pattern with chromophobic to slightly acidophilic cytoplasm. A few of tumor cells showed chromophobic cytoplasm. The nucleoli were conspicuous. Intranuclear inclusion bodies and variably-sized clear vacuoles were observed occasionally. Under electron microscope, marked mitochondrial abnormalities were observed, including increased mitochondria number, expanded hypertrophy, and absence of mitochondrial ridge fracture. Some mitochondrial matrices were dense, while some were vacuolated. Conclusions: Acidophil stem cell PitNET/adenoma is a rare type of pituitary adenomas/PitNETs. It often has a more clinically aggressive manner with immature cells, diffuse expression of PIT1, prolactin, and varying degrees of growth hormone expression. Because of the obvious diversity of their clinical hormone status and hormone immune expression, the diagnosis of this type tumor is still a challenge.
Collapse
Affiliation(s)
- L Lou
- Department of Pathology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - S X Du
- Department of Pathology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Y T Fu
- Department of Pathology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Q Q Shao
- Department of Pathology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - W L Guo
- Department of Pathology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Y P Zong
- Department of Pathology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - M M Qin
- Department of Pathology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - X X Tian
- Department of Pathology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Y H Li
- Department of Pathology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| |
Collapse
|
2
|
Hendrickson P, Oristian KM, Lou L, Ma Y, Cardona DM, Kirsch DG. Genetically Engineered Mouse Models of CIC-DUX4 Sarcoma Reveal an Unexpected Sensitivity to Histone Deacetylase (HDAC) Inhibition. Int J Radiat Oncol Biol Phys 2023; 117:S102-S103. [PMID: 37784272 DOI: 10.1016/j.ijrobp.2023.06.058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Undifferentiated small round cell sarcomas constitute a highly aggressive subtype of soft tissue sarcoma that affects adolescents and young adults. Frequently, these cancers are caused by a gene fusion between the DNA binding domain of capicua (CIC), a canonical tumor suppressor that normally acts as a transcriptional repressor, with the transcriptional activation domain of double homeobox 4 (DUX4). Given the rare nature of CIC-DUX4 sarcoma (CDS), obtaining patient tissues to study the mechanisms of disease is very challenging. Moreover, conducting clinical trials to identify radiosensitizers or other novel treatments is not possible underscoring the need for a primary animal model. Here, we report the development and characterization of the first genetically engineered mouse model of CDS and the use of this model to investigate novel therapies. MATERIALS/METHODS Using Cre-loxP technology, three genetically engineered mouse models of CDS were developed. The resulting tumors were characterized by hematoxylin and eosin (H&E) staining, immunohistochemistry (IHC), and RNA-sequencing. Cell lines from multiple primary and metastatic tumors were derived and used for Chromatin Immunoprecipitation (ChiP) sequencing, Rapid Immunoprecipitation mass spectrometry of Endogenous proteins (RIME), and targeted drug screening. RESULTS In all three models, spontaneous (Cre-independent) recombination occurred in chimeric animals resulting in the formation of soft tissue tumors, widespread metastasis to the lungs, liver, and brain, and 100% lethality within 4-8 weeks of life. The tumors histologically resembled human CDS and stained positive for an HA (hemagglutinin) epitope tag confirming transgene expression. Of 108 chimeric pups (generation 0, G0), only one male bred before succumbing to metastatic disease. G2 progeny now exhibit resistance to spontaneous recombination and tumor development enabling reliable propagation of one of the models for experimentation. Using tumor derived cell lines for integrative analyses of multi-omics datasets, we find evidence for a model where CIC-DUX4 functions as a neomorphic and oncogenic transcriptional activator, which cooperates with ETS family transcription factors to drive the CDS transcriptional program. Lastly, small molecule epigenetic drug screens in mouse and human CDS cell lines point to an unexpected sensitivity to HDAC inhibitors, which we hypothesize may be attributable to ETS factor hyperactivity. CONCLUSION Genetically engineered mouse models of CIC-DUX4 sarcoma form tumors that recapitulate the human disease. Using mouse tumors and tumor-derived cell lines, we identify a mechanistic role and potential therapeutic vulnerability that converges on the ETS family transcription factors.
Collapse
Affiliation(s)
- P Hendrickson
- Department of Radiation Oncology, Duke University, Durham, NC
| | - K M Oristian
- Department of Radiation Oncology, Duke University, Durham, NC
| | - L Lou
- Department of Radiation Oncology, Duke University, Durham, NC
| | - Y Ma
- Department of Radiation Oncology, Duke University, Durham, NC
| | - D M Cardona
- Department of Pathology, Duke University, Durham, NC
| | - D G Kirsch
- Department of Radiation Oncology, Duke University, Durham, NC
| |
Collapse
|
3
|
Zhang X, Wang H, Lou L, Li Q, Zhang L, Ge Y. Transcript expression profiling of fibromelanosis-related genes in black-bone chickens. Br Poult Sci 2021; 63:133-141. [PMID: 34402346 DOI: 10.1080/00071668.2021.1966750] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
1. The aim of the present study was to identify differentially expressed genes (DEGs) and metabolic pathways involved in this phenotype. Fibromelanosis is the most striking feature of black-bone chickens, such as the Silkie and Dongxiang indigenous breeds. Due to the accumulation of eumelanin in connective tissues, fibromelanosis manifests as black colouration of the skin, muscles, gut, and periosteum. Studies on fibromelanosis can provide useful information pertaining to human diseases and offer commercial value to the poultry industry. However, the genetic basis of fibromelanosis remains unclear.2. Digital gene expression analysis was performed on black and white skin samples collected from the HW1 black-bone chicken line to detect differences in genome-wide expression patterns. A total of >30 billion bp were sequenced, and 2,707,926,466 bp and 2,948,782,964 bp of clean data obtained for creation of libraries for black and white skin, respectively. In total, 252 DEGs from 15,508 mapped genes were identified with 83 up-regulated in white skin and 169 up-regulated in black skin.3. Gene ontology analysis highlighted that genes from the extracellular region and associated components were abundant among the DEGs. Pathway analysis revealed that many DEGs were linked to amino acid metabolism and the immune system. qRT-PCR validation using 14 genes showed good conformity with the sequence analysis of fibromelanosis-related genes.4. The results showed that L-dopachrometautomerase precursor (DCT), tyrosine aminotransferase (TAT), 4-hydroxyphenylpyruvate dioxygenase (HPD) from the tyrosine metabolism pathway, coagulation factor II (F2), fibrinogen beta chain (FGB), plasminogen (PLG) and complement component 7 (C7) from the complement and coagulation cascades were important genes in the fibromelanosis process in black-bone chickens. These candidate genes require further correlation analysis and functional verification.
Collapse
Affiliation(s)
- X Zhang
- Institute of Animal Husbandry, Hangzhou Academy of Agricultural Sciences, Hangzhou, China
| | - H Wang
- Institute of Animal Husbandry, Hangzhou Academy of Agricultural Sciences, Hangzhou, China
| | - L Lou
- Institute of Animal Husbandry, Hangzhou Academy of Agricultural Sciences, Hangzhou, China
| | - Q Li
- Institute of Animal Husbandry, Hangzhou Academy of Agricultural Sciences, Hangzhou, China
| | - L Zhang
- Institute of Animal Husbandry, Hangzhou Academy of Agricultural Sciences, Hangzhou, China
| | - Y Ge
- Institute of Animal Husbandry, Hangzhou Academy of Agricultural Sciences, Hangzhou, China
| |
Collapse
|
4
|
An P, Zhao Y, Yang FL, Zheng YB, Du JT, Lou L. [Effect of intratympanic injection of budesonide for otitis media with effusion in adolescents and adults]. Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2018; 31:1231-1237. [PMID: 29798368 DOI: 10.13201/j.issn.1001-1781.2017.16.004] [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] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Indexed: 02/05/2023]
Abstract
Objective:To assess the longitudinal curative effect and improvement of subjective symptoms by using intratympanic injection of budesonide (BUD) for OME patients over 12 years old and adults.Method:One hundred and eighty patients who were diagnosed as OME were recruited. A single-blind, randomized, parallel-control prospective study was performed. Dexamethasone (DEX) and sodium chloride (NS) were served as controls. The patients were randomly assigned into three groups, which respectively received intratympanic injection of BUD (0.5 mg/ml), DEX (5 mg/ml) or 0.9% NS solution (1 ml) once a week. Survival analysis was applied to compare the longitudinal curative effect among the three groups. Meanwhile, seven main subjective symptoms were scored by 10-point visual scale (VAS) and physician's evaluations were preformed during treatment and follow-up.Result:After adjustement for course of disease, volume and characters of effusion, the relative risk (RR) of BUD was 0.131 (95%CI: 0.053-0.354) when compared with NS. Survival curve showed, in BUD group, about 96.6%(57/59) of patients maintained effectiveness more than 3 months, 83.1%(49/59) were more than 1 year, and 81.4%(48/59) of the patients could sustain longer than 3 years. In DEX group, 73.2%(41/56) of patients showed effectiveness more than 3 months, 46.4%(26/56) were more than 1 year, and 42.9%(24/56) of the patients could sustain longer than 3 years. While in NS group, 50.8%(33/65) of the patients showed effectiveness more than 3 months, 26.2% (17/65) were more than 1 year, and 20.0%(13/65) of the patients could sustain longer than 3 years. Survival curve demonstrated that the rank of longitudinal therapeutic efficacy was BUD, DEX and NS (P< 0.05). Both BUD and DEX showed improvements in subjective symptoms and quality of life (except for mental stress) compared with NS (P< 0.05). In the aspect of improving the symptom of stuffy ear, BUD showed advantage over both DEX and NS. During and after treatment, no serious complications or sequelae were observed.Conclusion:Intratympanic injection with BUD for OME patients showed advantages in improving long-term therapeutic efficacy, it was a safe as well as effective intervention for children over age of 12 and adults suffering from OME.
Collapse
Affiliation(s)
- P An
- Department of Otorhinolaryngology, Shang Jin Nan Fu Hospital of Chengdu, Chengdu, 610041, China
| | - Y Zhao
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital
| | - F L Yang
- Department of Otorhinolaryngology, Suining Central Hospital
| | - Y B Zheng
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital
| | - J T Du
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital
| | - L Lou
- Department of Otorhinolaryngology Head and Neck Surgery, West China Hospital
| |
Collapse
|
5
|
Afzal S, Begum N, Zhao H, Fang Z, Lou L, Cai Q. Influence of endophytic root bacteria on the growth, cadmium tolerance and uptake of switchgrass (Panicum virgatumL.). J Appl Microbiol 2017; 123:498-510. [DOI: 10.1111/jam.13505] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 06/01/2017] [Accepted: 06/01/2017] [Indexed: 11/30/2022]
Affiliation(s)
- S. Afzal
- College of Life Sciences; Nanjing Agricultural University; Nanjing China
- Girls Degree College no.1; Gomal University; Dera Ismail Khan Pakistan
| | - N. Begum
- College of Life Sciences; Nanjing Agricultural University; Nanjing China
| | - H. Zhao
- College of Life Sciences; Nanjing Agricultural University; Nanjing China
| | - Z. Fang
- College of Life Sciences; Nanjing Agricultural University; Nanjing China
| | - L. Lou
- College of Life Sciences; Nanjing Agricultural University; Nanjing China
| | - Q. Cai
- College of Life Sciences; Nanjing Agricultural University; Nanjing China
| |
Collapse
|
6
|
Lou L, Zhou P, Qin XL, Lv D, An P, Chen M, Gao Y, Wen Y. [Application of tragus cartilage in the repair of cerebrospinal otorrhea:a report of 7 cases]. Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2016; 30:1331-1332. [PMID: 29797984 DOI: 10.13201/j.issn.1001-1781.2016.16.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Indexed: 11/12/2022]
|
7
|
Lou L, Zhu J, Lv D, Chen QR, Yang JM, Qin XL. [Modified radical mastoidectomy on"drum sinus" type chronic suppurative otitis media:our experience]. Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2016; 30:1068-1071. [PMID: 29798041 DOI: 10.13201/j.issn.1001-1781.2016.13.016] [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] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Indexed: 02/05/2023]
Abstract
Objective:To our experience of modified radical mastoidectomy on "drum sinus" type chronic suppurative otitis media.Method:We measured the size of tympanic sinus,the extent of meningeal plate lowering and the extent of sigmoid ante-displacement in 54 patients of chronic suppurative otitis media,and determined the criterion of "drum sinus".The patients who comply with the criterion received modified radical mastoidectomy and tympanoplasty via epitympanum approach.The patients were followed up for at least 3 months,The time of dry ear,growth of repaired tympanic membrane,and any complications such as dizziness,facial paralysis,cerebrospinal fluid leakage were recorded.Result:Twenty-nine out of the 54 CSOM patients complied with the criterion of drum sinus.Two cases were lost to follow-up.Therefore,27 cases were included in the study.Three months after the operation,the rate of dry ear was 81.5% Tympanic membrane was successfully repaired in 77.8% of the patients.Three cases had dizziness after operation.No facial paralysis or cerebrospinal fluid leakage was observed.Conclusion:For"drum sinus" type chronic suppurative otitis media,the modified radical mastoidectomy and tympanoplasty via epitympanum approach can be taken.
Collapse
Affiliation(s)
- L Lou
- Department of Otolaryngology-Head and Neck Surgery,West China Hospital,Sichuan University,Chengdu,610041,China
| | - J Zhu
- Department of Otolaryngology,Tianfu New Area People's Hospital of Chengdu
| | - D Lv
- Department of Otolaryngology-Head and Neck Surgery,West China Hospital,Sichuan University,Chengdu,610041,China
| | - Q R Chen
- Department of Otolaryngology-Head and Neck Surgery,West China Hospital,Sichuan University,Chengdu,610041,China
| | - J M Yang
- Department of Otolaryngology-Head and Neck Surgery,West China Hospital,Sichuan University,Chengdu,610041,China
| | - X L Qin
- Department of Otolaryngology-Head and Neck Surgery,West China Hospital,Sichuan University,Chengdu,610041,China
| |
Collapse
|
8
|
Chen SD, Hou PF, Lou L, Jin X, Wang TH, Xu JL. The correlation between MR diffusion-weighted imaging and pathological grades on glioma. Eur Rev Med Pharmacol Sci 2014; 18:1904-1909. [PMID: 25010621] [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] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVE This work intends to quantitatively analyze on pathological grade of glioma using Magnetic Resonance (MR) diffusion weighted imaging (DWI) and exploring the relativity of pathological grade and Apparent Diffusion Coefficient (ADC) value of MR diffusion weighted imaging. PATIENTS AND METHODS 40 patients with glioma accepted the MR diffusion weighted imaging to measure the ADC value of tumor with 3.0T MR machine before the surgery. Tumor samples were sent for pathologic diagnosis and tumor cell density measurement after the operation. The acquired data were analyzed statistically. RESULTS The ADC values of low-grade (WHO I-II) glioma were higher than that of high-grade (WHO III-IV), but the cell density of low-grade glioma was apparently lower than that of high-grade glioma. The ADC values and density of tumor cells were negatively correlated with WHO malignant grades, while the density of cells of glioma was positively correlated with WHO malignant grades. CONCLUSIONS MR diffusion weighted imaging is an objective and effective examination method.
Collapse
Affiliation(s)
- S-D Chen
- Department of Neurosurgery, Zhejiang Provincial People's Hospital, Hangzhou, Zhejiang, China.
| | | | | | | | | | | |
Collapse
|
9
|
Affiliation(s)
- B C Tsui
- University of Alberta, Edmonton, Canada.
| | | |
Collapse
|
10
|
Chai H, Chen WZ, Zhu J, Xu Y, Lou L, Yang T, He W, Wang W. Processing of facial expressions of emotions in healthy volunteers: an exploration with event-related potentials and personality traits. Neurophysiol Clin 2012. [PMID: 23181967 DOI: 10.1016/j.neucli.2012.04.087] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
AIMS OF THE STUDY Previous studies have shown that event-related potentials (ERPs) are modulated by anxiety or psychopathic personality traits. Therefore, we hypothesized that the automatic processing of facial expressions of emotions (FEE) is also correlated with related disordered personality traits. METHODS Thirty-seven healthy volunteers underwent both an "oddball" ERP recording to facial expressions of Anger, Happiness, Sadness, and Neutral, and a test of the Dimensional Assessment of Personality Pathology (DAPP). RESULTS Mean reaction time was longer in response to anger than to other facial expressions. Facial expressions of Anger, Happiness and Sadness did not affect N1 (N170). By contrast, Happiness elicited a delayed P2, Anger elicited both a smaller N2 and a delayed P3b, and both Happiness and Anger elicited a P3b of higher amplitude. In addition, P3a latencies to Happiness were negatively correlated with DAPP Identity problems, and P3b latencies to Happiness were negatively correlated with DAPP Stimulus seeking, Callousness, Passive aggressivity, and Narcissism. CONCLUSION Our study demonstrates that Anger implicitly captures attentional resources, and Happiness triggers more facilitated processing in individuals with dissocial traits.
Collapse
Affiliation(s)
- H Chai
- Department of Clinical Psychology and Psychiatry, Zhejiang University School of Medicine, Yuhangtang Road 866, Hangzhou, Zhejiang 310058, China
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Pino CJ, Lou L, Smith PL, Ding F, Pagani FD, Buffington DA, Humes HD. A selective cytopheretic inhibitory device for use during cardiopulmonary bypass surgery. Perfusion 2012; 27:311-9. [PMID: 22508804 DOI: 10.1177/0267659112444944] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Systemic inflammatory response syndrome (SIRS) can occur in association with cardiopulmonary bypass (CPB) surgery, resulting in multiple organ dysfunction (MOD). Activated neutrophils have been implicated as major inciting factors in this process. Neutrophil-depleting filters incorporated within the extracorporeal blood circuit during CPB have been developed and evaluated, with inconsistent clinical results. METHODS A novel, biomimetic, selective cytopheretic device (SCD) was tested in vitro within a blood circuit to assess safety and interactions with blood components and further evaluated ex vivo in a bovine model of CPB surgery during ventricular assist device implantation. RESULTS In vitro blood circuit studies demonstrated that the SCD reduces circulating neutrophils while maintaining low rates of hemolysis compared to current leukocyte-reduction filters. In the bovine CPB model, animals without SCD treatment (No SCD) demonstrated an increase in circulating white blood cell (WBC) and neutrophil counts, steadily increasing throughout CPB. SCD with only systemic heparin anticoagulation (SCD-H) acutely reduced neutrophils for the first 2 hrs of CPB, but followed with a greater than 6-fold increase in neutrophil counts. SCD treatment with regional citrate anticoagulation along the SCD circuit (SCD-C) reduced systemic neutrophil counts throughout 4 hrs of CPB despite lower amounts of eluted cells from the SCD. When analyzed for immature neutrophils, the control and SCD-H showed increasing counts at later time-points, not seen in the SCD-C group, suggesting a more complex mechanism of action than simple leukoreduction. CONCLUSIONS These results suggest that SCD-C therapy may disrupt the systemic leukocyte response during CPB, leading to improved outcomes for CPB-mediated MOD.
Collapse
Affiliation(s)
- C J Pino
- Innovative BioTherapies Inc., Ann Arbor, MI 48108, USA
| | | | | | | | | | | | | |
Collapse
|
12
|
Zhu JM, Zhao YY, Chen SD, Zhang WH, Lou L, Jin X. Functional recovery after transplantation of neural stem cells modified by brain-derived neurotrophic factor in rats with cerebral ischaemia. J Int Med Res 2011; 39:488-98. [PMID: 21672352 DOI: 10.1177/147323001103900216] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Functional recovery after transplantation of brain-derived neurotrophic factor (BDNF)-modified neural stem cells (NSCs) was evaluated in a rat model of cerebral ischaemia damage induced by temporary middle cerebral artery occlusion (tMCAO). Western blotting and enzyme-linked immunosorbent assay demonstrated upregulated BDNF protein expression by rat embryonic NSCs transfected with the human BDNF gene (BDNF-NSCs). BDNF-NSCs stimulated neurite outgrowth in cocultured dorsal root ganglion neurons, suggesting that BDNF increased neurogenesis in vitro. In vivo, BDNF promoted recovery of tMCAO. Phosphate-buffered saline, untransformed NSCs or BDNF-NSCs were introduced into the penumbra zone of the right striatum of tMCAO rats and neurological function deficit was assessed for up to 12 weeks using the neurological severity score (NSS). The NSS was significantly lower in the BDNF-NSC transfected transplant group than in all the other groups from week 10. BDNF-NSCs recovered 1 week after transplantation expressed BDNF protein. Transplanted NSCs had differentiated into mature neurons 12 weeks after transplantation. Transgenic NSCs have potential as a therapeutic agent for brain ischaemia.
Collapse
Affiliation(s)
- J M Zhu
- Department of Neurosurgery, Zhejiang Provincial People's Hospital, Hangzhou, China.
| | | | | | | | | | | |
Collapse
|
13
|
Wang Y, Yu L, Wang J, Lou L, Du W, Zhu Z, Peng H, Zhu J. A novel l-lactate sensor based on enzyme electrode modified with ZnO nanoparticles and multiwall carbon nanotubes. J Electroanal Chem (Lausanne) 2011. [DOI: 10.1016/j.jelechem.2011.06.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
14
|
Wu, Zhai J, Zhang D, Lou L, Wang S. Effects of YiqiHuoxue medicine on ventricular fibrillation threshold and connexin 43 in rats with myocardial infarction. Heart 2011. [DOI: 10.1136/heartjnl-2011-300867.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
15
|
Prhavc M, Dyatkina N, Keicher J, Liehr S, Koo-McCoy S, Latour D, Fung K, Dunlop K, Pouliot J, Wang T, Li W, Lou L, Roberts C, Griffith R. Synthesis and Biological Activity of 7-Deaza-7-ethynyl-2'-deoxy-2'-fluoro-2'-C-methyladenosine and its 2'-C-Methyl-ribo Analogue. ACTA ACUST UNITED AC 2008:643-4. [DOI: 10.1093/nass/nrn325] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
16
|
Du L, Zhu X, Gerber R, Huffman J, Lou L, Jorgenson J, Yu F, Zaleta-Rivera K, Wang Q. Biosynthesis of sphinganine-analog mycotoxins. J Ind Microbiol Biotechnol 2008; 35:455-64. [PMID: 18214562 DOI: 10.1007/s10295-008-0316-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2007] [Accepted: 01/10/2008] [Indexed: 10/22/2022]
Abstract
Sphinganine-analog mycotoxins (SAMT) are polyketide-derived natural products produced by a number of plant pathogenic fungi and are among the most economically important mycotoxins. The toxins are structurally similar to sphinganine, a key intermediate in the biosynthesis of ceramides and sphingolipids, and competitive inhibitors for ceramide synthase. The inhibition of ceramide and sphingolipid biosynthesis is associated with several fatal diseases in domestic animals and esophageal cancer and neural tube defects in humans. SAMT contains a highly reduced, acyclic polyketide carbon backbone, which is assembled by a single module polyketide synthase. The biosynthesis of SAMT involves a unique polyketide chain-releasing mechanism, in which a pyridoxal 5'-phosphate-dependent enzyme catalyzes the termination, offloading and elongation of the polyketide chain. This leads to the introduction of a new carbon-carbon bond and an amino group to the polyketide chain. The mechanism is fundamentally different from the thioesterase/cyclase-catalyzed polyketide chain releasing found in bacterial and other fungal polyketide biosynthesis. Genetic data suggest that the ketosynthase domain of the polyketide synthase and the chain-releasing enzyme are important for controlling the final product structure. In addition, several post-polyketide modifications have to take place before SAMT become mature toxins.
Collapse
Affiliation(s)
- L Du
- Department of Chemistry, University of Nebraska, Lincoln, NE 68588, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Abstract
P-glycoprotein (P-gp) pumps multiple types of drugs out of the cell, using energy generated from ATP, and confers multidrug resistance (MDR) on cancer cells. ZD6474 is an orally active, selective inhibitor of the vascular endothelial growth factor receptor, epidermal growth factor receptor, and rearranged during transfection tyrosine kinases. This study was designed to examine whether ZD6474 reverses P-gp-mediated MDR in cancer cells. Here, we show that clinically achievable levels of ZD6474 reverse P-gp-mediated MDR of the P-gp-overexpressing cell lines derived from breast cancer, MCF-7/adriamycin (ADR), and human oral epidermoid carcinoma, KBV200 to ADR, docetaxel, and vinorelbine. This ability to reverse the P-gp-mediated resistance is comparable to that of another frequently used reversal agent known as verapamil. ZD6474 itself moderately inhibits the proliferation of both MCF-7 and MCF-7/ADR cells with almost equal activity, but its inhibitory effect is not altered by co-incubation with verapamil, suggesting that ZD6474 may not be a substrate of P-gp. In addition, ZD6474 increases the intracellular accumulation of the P-gp substrate, rhodamine-123, and ADR, by enhancing the uptake and/or decreasing the efflux of these compounds in resistant cells. Further studies show that ZD6474 stimulates ATPase activity in a dose-dependent manner, which is required for the proper function of P-gp. In contrast, ZD6474 does not inhibit the expression level of P-gp. Our results suggest that ZD6474 is capable of reversing MDR in cancer cells by directly inhibiting the function of P-gp, a finding that may have clinical implications for ZD6474.
Collapse
Affiliation(s)
- Y Mi
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - L Lou
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- E-mail:
| |
Collapse
|
18
|
Affiliation(s)
- L Lou
- International Pain Institute, Texas Tech University Health Sciences Center, Lubbock, Texas 79413, USA
| | | | | |
Collapse
|
19
|
Lou L, Shou T, Li Z, Li W, Gu Y. Transhemispheric functional reorganization of the motor cortex induced by the peripheral contralateral nerve transfer to the injured arm. Neuroscience 2006; 138:1225-31. [PMID: 16426770 DOI: 10.1016/j.neuroscience.2005.11.062] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2005] [Revised: 11/08/2005] [Accepted: 11/29/2005] [Indexed: 11/26/2022]
Abstract
Peripheral nerve injury in a limb usually causes functional reorganization of the contralateral motor cortex. However, a dynamic process of the novel transhemispheric functional reorganization in the motor cortex was found in adult rats after transferring the seventh cervical nerve root from the contralateral healthy side to the injured limb. Initially the ipsilateral motor cortex activated the injured forepaw for 5 months after the operation. Then, both hemispheres of the cortex activated the injured forepaw, and finally the contralateral cortex exclusively controlled the injured forepaw. It is concluded an extensive functional shift occurred between two hemispheres based on neural plasticity in the CNS. The experimental results of the later lesions of the ipsilateral cortex suggest that maintaining transhemispheric functional reorganization does not depend on the corpus callosum, but depends on mechanisms involving central axonal sprouting. Possible mechanisms underlying the alternative changes in cortical functions were discussed in rats and in patients having similar operations.
Collapse
Affiliation(s)
- L Lou
- Vision Research Laboratory, School of Life Sciences, Fudan University, 220 Handan Road, Shanghai 200433, China
| | | | | | | | | |
Collapse
|
20
|
Affiliation(s)
- L Lou
- Department of Anesthesiology, International Pain Institute, Texas Tech University Health Sciences Center, Lubbock, Texas 79414, USA
| | | |
Collapse
|
21
|
Affiliation(s)
- J W M Geurts
- Dept. of Anesthesiology, Rijnstate Hospital, Arnhem, The Netherlands
| | | | | | | | | |
Collapse
|
22
|
Zhu J, Xiong X, Zhao S, Wang Z, Lou L, Hang Q. [Plasma Lp (a) levels and correlation of Lp (a) with fibrinolysis activation in chronic renal failure]. Hunan Yi Ke Da Xue Xue Bao 2002; 24:366-8. [PMID: 12080650] [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] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Plasma Lp (a) concentration and activation of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1(PAI-1) were determined in 50 patients with chronic renal failure (CRF) and in 50 healthy subjects. The results demonstrated that plasma concentration of Lp(a) was significantly higher and plasma t-PA activation was significantly lower in CRF patients than in healthy subjects. With multivariate analyses, plasma Lp(a) concentration was positively correlated with the total amount of 24 h uric protein, plasma BUN and uric protein concentration. Moreover, a negative significant correlation between plasma Lp(a) levels and t-PA activation was observed. Plasma Lp(a) levels did not show a correlation to PAI-1 activation. It is indicated that renal function may contribute to moderate plasma Lp(a) concentration and elevated Lp(a) levels may be related with fibrinolytic impairment.
Collapse
Affiliation(s)
- J Zhu
- Department of Kidney Internal Medicine, Second Affiliated Hospital, Hunan Medical University, Changsha 410011
| | | | | | | | | | | |
Collapse
|
23
|
Abstract
The effect of voluntary attention on afterimage fragmentation was explored in two experiments. The afterimage, in the form of a 30 degrees-tilted star of David, was generated after prolonged steady fixation in the first experiment, and with a brief and intense flash in the second experiment. Subjects were instructed to select various target shapes in the afterimage for attention and, at the same time, observe what was visible or invisible. Verbal reports and manual responses to afterimage changes were analyzed. Attended shapes were found to disappear from awareness Faster than unattended ones (experiment 1), and complementary shapes were found to predominate visual awareness when one of the pair was selected for attention (experiment 2). Voluntary attention was also found to affect closure (filling-in of enclosed regions) and smoothing of line figures in afterimages.
Collapse
Affiliation(s)
- L Lou
- Department of Psychology, Grand Valley State Universty, Allendale, MI 49401, USA.
| |
Collapse
|
24
|
Dominguez E, Latif O, Rozen D, Sahinler B, Orbegozo M, Edmunds A, Lou L, Day M, Racz G, Raj P. Subdural Blood Patch for the Treatment of Persistent CSF Leak After Permanent Intrathecal Catheter Implantation: A Report of Two Cases. Pain Pract 2001; 1:344-53. [PMID: 17147576 DOI: 10.1046/j.1533-2500.2001.01036.x] [Citation(s) in RCA: 5] [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] [Indexed: 11/20/2022]
Abstract
A CSF leak that persists despite conservative therapy may significantly increase the morbidity associated with implantable intrathecal drug delivery systems. This report presents 2 cases where the application of a subdural blood patch led to the satisfactory resolution of a persistent CSF leak after previous epidural blood patches had failed.
Collapse
Affiliation(s)
- E Dominguez
- Texas Tech University Health Sciences Center, Lubbock, Texas 79414, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Chen H, Yin M, Lian R, Lou L, Zhang W, Xia S. [Luminescence dependence upon concentration and temperature in YPO4:Pr3+]. Guang Pu Xue Yu Guang Pu Fen Xi 2001; 21:151-154. [PMID: 12947608] [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] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Under selective excitation 3P0 state of Pr3+ ion in YPO4, the emission spectra and fluorescence decay curves are measured at different concentrations and temperatures. The origin of the spectral line located at 613.2 nm has been discussed and assigned to be the 1D2 (gamma 3)-->3H4 (gamma 5) transition. The different concentration dependence of emission intensities of levels 3P0 and 1D2 has been studied. Using static model, the fluorescence decay curve of 1D2 level is fitted, and the result shows that the cross-relaxation caused by the interaction of dipole-quadrupole between adjacent Pr3+ ions results in the concentration quenching.
Collapse
Affiliation(s)
- H Chen
- Structure Research Laboratory, University of Science and Technology of China, Academia Sinica, 230026 Hefei
| | | | | | | | | | | |
Collapse
|
26
|
Abstract
Uncommon stimulation refers to the use of peripheral nerve and spinal cord stimulation for nontraditional applications. There has been much interest recently with subcutaneous suboccipital stimulation for occipital neuralgia, sacral stimulation for pelvic pain, trigeminal stimulation for trigeminal neuralgia, and spinal cord stimulation for angina and peripheral ischemia. The indications and techniques used for accomplishing each method are discussed.
Collapse
Affiliation(s)
- L Lou
- Department of Anesthesiology, Texas Tech University Health Sciences Center, 3601 4th Street, Room 1C282, Lubbock, TX 79430, USA
| |
Collapse
|
27
|
Bennett G, Serafini M, Burchiel K, Buchser E, Classen A, Deer T, Du Pen S, Ferrante FM, Hassenbusch SJ, Lou L, Maeyaert J, Penn R, Portenoy RK, Rauck R, Willis KD, Yaksh T. Evidence-based review of the literature on intrathecal delivery of pain medication. J Pain Symptom Manage 2000; 20:S12-36. [PMID: 10989255 DOI: 10.1016/s0885-3924(00)00204-9] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.6] [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: 02/06/2023]
Abstract
Evidence-based medicine depends on the existence of controlled clinical trials that establish the safety and efficacy of specific therapeutic techniques. Many interventions in clinical practice have achieved widespread acceptance despite little evidence to support them in the scientific literature; the critical appraisal of these interventions based on accumulating experience is a goal of medicine. To clarify the current state of knowledge concerning the use of various drugs for intraspinal infusion in pain management, an expert panel conducted a thorough review of the published literature. The exhaustive review included 5 different groups of compounds, with morphine and bupivacaine yielding the most citations in the literature. The need for additional large published controlled studies was highlighted by this review, especially for promising agents that have been shown to be safe and efficacious in recent clinical studies.
Collapse
Affiliation(s)
- G Bennett
- Department of Neurology, MCP Hahnemann University, Philadelphia, PA, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Bennett G, Burchiel K, Buchser E, Classen A, Deer T, Du Pen S, Ferrante FM, Hassenbusch SJ, Lou L, Maeyaert J, Penn R, Portenoy RK, Rauck R, Serafini M, Willis KD, Yaksh T. Clinical guidelines for intraspinal infusion: report of an expert panel. PolyAnalgesic Consensus Conference 2000. J Pain Symptom Manage 2000; 20:S37-43. [PMID: 10989256 DOI: 10.1016/s0885-3924(00)00202-5] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.9] [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
Consensus guidelines developed by an expert panel are helpful to clinicians when there is variation in practice and lack of a firm evidence base for an intervention, such as intraspinal therapy for pain. An internet-based survey of practitioners revealed remarkable variation in practice patterns surrounding intraspinal therapy. This prompted an interdisciplinary panel with extensive clinical experience in intraspinal infusion therapy to evaluate the results of the survey, the systematic reviews of the literature pertaining to this approach, and their own clinical experience with long-term spinal infusions. The panel proposed a scheme for the selection of drugs and doses for intraspinal therapy, and suggested guidelines for administration that would increase the likelihood of a successful outcome. These expert panel guidelines were designed to provide an initial structure for clinical decision making that is based on the best available evidence and the perspectives of experienced clinicians.
Collapse
Affiliation(s)
- G Bennett
- Department of Neurology, MCP Hahnemann University, Philadelphia, PA, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
|
30
|
Abstract
A circular array of six discs, three green and three orange in alternate positions, was presented against a uniform grey background. Sixteen observers maintained steady fixation at the centre of the array, and were instructed to direct their attention to three discs of one colour and to ignore the three discs of the other colour. In about 10 s (mean = 11.35 s), some discs started to fade away from awareness. Of those starting to fade, most (mean = 81.3%) were those selected for attention. The faded discs remained out of awareness for up to a few seconds (mean = 1.55 s) during which other discs were clearly visible. The fading increased with eccentricity, a defining characteristic of Troxler fading. However, the selectivity of the fading strongly suggests that voluntary attention can have an inhibitory effect on early sensory processing. Were the fading entirely due to local sensory adaptation, the unattended stimuli would have to be equally adapted and yet somehow remain visible for seconds, which is not plausible.
Collapse
Affiliation(s)
- L Lou
- Department of Psychology, University of Hong Kong, Hong Kong.
| |
Collapse
|
31
|
Abstract
Speed-accuracy tradeoff (SAT) refers to the inverse relation between speed and accuracy found in many tasks. The present study employed reaction times (RTs) and movement-related brain potentials arising during the RT interval (lateralized readiness potentials; LRPs) to examine the mechanisms by which people control their position along an SAT continuum. Many models of SAT postulate that changes in position across conditions (macro-tradeoffs) and trial-by-trial variations within conditions (micro-tradeoffs) are mediated, at least in part, by the same mechanisms. These include: (1) all models that postulate mixtures of guesses and accurate responses and (2) some models postulating decision criterions applied to accumulating evidence or response tendencies. Such models would seem to be rejected for conditions under which macro- and micro-tradeoffs can be shown to involve no stages of RT in common. Under the present conditions, the two types of SAT produced additive effects on RT, with the macro-tradeoff involving only that portion of the RT interval occurring after LRP onset and the micro-tradeoff involving only that portion before LRP onset. These findings imply that the two types of SAT arose during different serial stages of RT and that the macro-tradeoff involved only stages occurring after differential preparation of the two hands had begun.
Collapse
Affiliation(s)
- A Osman
- Department of Psychology, University of Pennsylvania, 3815 Walnut Street, Philadelphia, PA 19104, USA.
| | | | | | | | | | | |
Collapse
|
32
|
Zhao G, Gao P, Zhang H, Lou L, Qiao H, She M. [Cloning whole length cDNA of related genes responsible for smooth muscle cells proliferation in atherogenesis and study on its function]. Zhonghua Bing Li Xue Za Zhi 1999; 28:352-5. [PMID: 11869548] [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] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To clone whole length cDNA of the related genes responsible for vascular smooth muscle cell (SMC) proliferation in atherogenesis, and to study its function. METHODS ox-LDL was added as a stimulant to the SMC culture medium. Subtractive library was established using subtractive hybridization technique in order to clone the related genes fragments. With the whole length cDNA library established, the whole length cDNA of the related gene was cloned. The protein expressed was studied. RESULTS 4 new gene fragments and one whole length cDNA were cloned. The new cloned gene is able to express a protein of about 44000 daltons and closely related to the activity of ox-LDL. CONCLUSIONS The new cloned gene is considered responsible for SMC proliferation.
Collapse
MESH Headings
- Arteriosclerosis/genetics
- Arteriosclerosis/pathology
- Cell Division/drug effects
- Cell Division/genetics
- Cloning, Molecular
- DNA, Complementary/genetics
- Electrophoresis, Polyacrylamide Gel
- Escherichia coli/genetics
- Gene Expression
- Genetic Predisposition to Disease/genetics
- Humans
- Lipoproteins, LDL/metabolism
- Lipoproteins, LDL/pharmacology
- Molecular Weight
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
Collapse
Affiliation(s)
- G Zhao
- Department of Pathology, Institute of Basic Medical Sciences, Peking Union Medical College, Beijing 100005
| | | | | | | | | | | |
Collapse
|
33
|
Keithley EM, Erkman L, Bennett T, Lou L, Ryan AF. Effects of a hair cell transcription factor, Brn-3.1, gene deletion on homozygous and heterozygous mouse cochleas in adulthood and aging. Hear Res 1999; 134:71-6. [PMID: 10452377 DOI: 10.1016/s0378-5955(99)00070-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [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: 10/18/2022]
Abstract
The transcription factor Brn-3.1, is expressed in the inner ear hair cells throughout life and is necessary for the development of these cells. Mutant mice in which the Brn-3.1 encoding region has been deleted have no identifiable hair cells, greatly reduced numbers of spiral ganglion cells and are deaf. A mutation in the human homologue of this gene has been shown to be related to adult onset, sensorineural hearing loss (Vahava et al., 1998). The question whether haploinsufficiency in the mutant Brn-3.1 mouse with a mixed C57BL6/129Sv genetic background could affect the adult or aged cochlea was tested, therefore, by measuring the auditory brainstem responses and examining the cochlea's histologically at 2, 18 and 24 months of age. The heterozygotes had a comparable hearing to the wild-type animals and similar patterns of cochlear degeneration. Both groups showed an about 30 dB hearing loss beginning at 18 months of age, outer hair cell degeneration and loss of spiral ganglion neurons in the basal turn. There appeared to be no effect of Brn-3.1 haploinsufficiency on the mouse cochlea, implying that one intact copy of the gene is sufficient to maintain a normal cochlea.
Collapse
Affiliation(s)
- E M Keithley
- Department of Otolaryngology, University of California, San Diego Medical School, VAMC, La Jolla 92093-0666, USA.
| | | | | | | | | |
Collapse
|
34
|
Pillonnet A, Garapon C, Champeaux C, Bovier C, Brenier R, Lou L, Catherinot A, Jacquier B, Mugnier J. Dépôt par ablation laser de guides d'onde d'alumine pure et dopée en europium. Propriétés structurales et optiques. ACTA ACUST UNITED AC 1999. [DOI: 10.1051/jp4:1999543] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
|
35
|
Lou L, Zhou T, Wang P, Pei G. Modulation of Ca2+/calmodulin-dependent protein kinase II activity by acute and chronic morphine administration in rat hippocampus: differential regulation of alpha and beta isoforms. Mol Pharmacol 1999; 55:557-63. [PMID: 10051541] [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: 02/11/2023] Open
Abstract
Calcium/calmodulin-dependent protein kinase II (CaMK II) has been shown to be involved in the regulation of opioid receptor signaling. The present study showed that acute morphine treatment significantly increased both Ca2+/calmodulin-independent and Ca2+/calmodulin-dependent activities of CaMK II in the rat hippocampus, with little alteration in the protein level of either alpha or beta isoform of CaMK II. However, chronic morphine treatment, by which rats were observed to develop apparent tolerance to morphine, significantly down-regulated both Ca2+/calmodulin-independent and Ca2+/calmodulin-dependent activities of CaMK II and differentially regulated the expression of alpha and beta isoforms of CaMK II at protein and mRNA levels. Application of naloxone or discontinuation of morphine treatment after chronic morphine administration, which induced the withdrawal syndrome of morphine, resulted in the overshoot of CaMK II (at both protein and mRNA levels) and its kinase activity. The phenomena of overshoot were mainly observed in the beta isoform of CaMK II but not in the alpha isoform. The effects of both acute and chronic morphine treatments on CaMK II could be completely abolished by the concomitant application of naloxone, indicating that the effects of morphine were achieved through activation of opioid receptors. Our data demonstrated that both acute and chronic morphine treatments could effectively modulate the activity and the expression of CaMK II in the hippocampus.
Collapse
Affiliation(s)
- L Lou
- Shanghai Institute of Cell Biology, Chinese Academy of Sciences, Shanghai, People's Republic of China
| | | | | | | |
Collapse
|
36
|
Jishi RA, Flores RM, Valderrama M, Lou L, Bragin J. Equilibrium Geometry and Properties Of Cyclo[(Gly-d-Ala)4] and {Cyclo[(Gly-d-Ala)4]}2 from Density Functional Theory. J Phys Chem A 1998. [DOI: 10.1021/jp981997j] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- R. A. Jishi
- Department of Physics, California State University, Los Angeles, California 90032, Wavefunction, Inc., 18401 Van Karman, Irvine, California 92715, and Department of Chemistry, California State University, Los Angeles, California 90032
| | - R. M. Flores
- Department of Physics, California State University, Los Angeles, California 90032, Wavefunction, Inc., 18401 Van Karman, Irvine, California 92715, and Department of Chemistry, California State University, Los Angeles, California 90032
| | - M. Valderrama
- Department of Physics, California State University, Los Angeles, California 90032, Wavefunction, Inc., 18401 Van Karman, Irvine, California 92715, and Department of Chemistry, California State University, Los Angeles, California 90032
| | - L. Lou
- Department of Physics, California State University, Los Angeles, California 90032, Wavefunction, Inc., 18401 Van Karman, Irvine, California 92715, and Department of Chemistry, California State University, Los Angeles, California 90032
| | - J. Bragin
- Department of Physics, California State University, Los Angeles, California 90032, Wavefunction, Inc., 18401 Van Karman, Irvine, California 92715, and Department of Chemistry, California State University, Los Angeles, California 90032
| |
Collapse
|
37
|
Liu X, Lou L, Jiang J. [Induction of apoptosis and differentiation in human leukemia cell line HL-60 by synthetic retinoid Ro13-7410]. Zhonghua Xue Ye Xue Za Zhi 1998; 19:241-3. [PMID: 11243120] [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] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVE To investigate the effect of the synthetic retinoid Ro13-7410 on HL-60 cells. METHODS Trypan blue exclusion was used to determine viability. Apoptosis was assessed by cell morphology and PCD-assay-kit. Differentiation was assessed by morphology and NBT reduction. RESULTS Incubation of the HL-60 cells with 10(-6)-10(-8) mol/L Ro14-7410 resulted in the suppression of cell growth, the induction of cell apoptosis and differentiation. CONCLUSION Ro13-7410 suppressed HL-60 cell growth mainly via induction of apoptosis.
Collapse
Affiliation(s)
- X Liu
- Department of Hematology, First Affiliated Hospital, Chongqing University of Medical Sciences, Chongqing 400016
| | | | | |
Collapse
|
38
|
|
39
|
Song WJ, Sternberg LR, Kasten-Sportès C, Keuren ML, Chung SH, Slack AC, Miller DE, Glover TW, Chiang PW, Lou L, Kurnit DM. Isolation of human and murine homologues of the Drosophila minibrain gene: human homologue maps to 21q22.2 in the Down syndrome "critical region". Genomics 1996; 38:331-9. [PMID: 8975710 DOI: 10.1006/geno.1996.0636] [Citation(s) in RCA: 134] [Impact Index Per Article: 4.8] [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: 02/03/2023]
Abstract
The presence of an extra copy of human chromosome 21 (trisomy 21), especially region 21q22.2, causes many phenotypes in Down syndrome, including mental retardation. To study genes potentially responsible for some of these phenotypes, we cloned a human candidate gene (DYRK) from 21q22.2 and its murine counterpart (Dyrk) that are homologous to the Drosophila minibrain (mnb) gene required for neurogenesis and to the rat Dyrk gene (dual specificity tyrosine phosphorylation regulated kinase). The three mammalian genes are highly conserved, >99% identical at the protein level over their 763-amino-acid (aa) open reading frame; in addition, the mammalian genes are 83% identical over 414 aa to the smaller 542-aa mnb protein. The predicted human DYRK and murine Dyrk proteins both contain a nuclear targeting signal sequence, a protein kinase domain, a putative leucine zipper motif, and a highly conserved 13-consecutive-histidine repeat. Fluorescence in situ hybridization and regional mapping data localize DYRK between markers D21S336 and D21S337 in the 21q22.2 region. Northern blot analysis indicated that both human and murine genes encode approximately 6-kb transcripts. PCR screening of cDNA libraries derived from various human and murine tissues indicated that DYRK and Dyrk are expressed both during development and in the adult. In situ hybridization of Dyrk to mouse embryos (13, 15, and 17 days postcoitus) indicates a differential spatial and temporal pattern of expression, with the most abundant signal localized in brain gray matter, spinal cord, and retina. The observed expression pattern is coincident with many of the clinical findings in trisomy 21. Its chromosomal locus (21q22. 2), its homology to the mnb gene, and the in situ hybridization expression patterns of the murine Dyrk combined with the fact that transgenic mice for a YAC to which DYRK maps are mentally deficient suggest that DYRK may be involved in the abnormal neurogenesis found in Down syndrome.
Collapse
Affiliation(s)
- W J Song
- Howard Hughes Medical Institute, University of Michigan Medical Center, Ann Arbor, Michigan 48109, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Wang LS, Wu H, Desai SR, Lou L. Electronic structure of small copper oxide clusters: From Cu2O to Cu2O4. Phys Rev B Condens Matter 1996; 53:8028-8031. [PMID: 9982259 DOI: 10.1103/physrevb.53.8028] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
41
|
Sun P, Lou L, Maurer RA. Regulation of activating transcription factor-1 and the cAMP response element-binding protein by Ca2+/calmodulin-dependent protein kinases type I, II, and IV. J Biol Chem 1996; 271:3066-73. [PMID: 8621702 DOI: 10.1074/jbc.271.6.3066] [Citation(s) in RCA: 161] [Impact Index Per Article: 5.8] [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] [Indexed: 01/31/2023] Open
Abstract
The ability of activating transcription factor-1 (ATF1) or the cAMP response element-binding protein (CREB) to enhance transcription can be stimulated by increases in intracellular Ca2+ concentrations. To identify protein kinases which may mediate the ability of Ca2+ to activate these transcription factors, we compared the ability of constitutively active forms of several Ca2+/calmodulin-dependent protein kinases (CaM kinases) to activate ATF1 or CREB. We find that constitutively active CaM kinase I and IV can activate both ATF1 and CREB. In addition, expression vectors for full-length CaM kinase I and IV were able to augment the ability of Ca2+ influx to activate ATF1 or CREB consistent with a role for these kinases in mediating transcriptional responses to Ca2+ signaling. In contrast, CaM kinase II was unable to activate either ATF1 or CREB. These findings provide a potential mechanism that may permit variation in the ability of ATF1 and CREB to respond to changes in intracellular Ca2+ concentrations depending on differences in the relative concentrations of specific CaM kinases.
Collapse
Affiliation(s)
- P Sun
- Department of Cell and Developmental Biology, Oregon Health Sciences University, Portland, Oregon 97201, USA
| | | | | |
Collapse
|
42
|
Akpati HC, Mackey J, Nordlander P, Lou L. A density‐functional study of cluster reactivity. III. NH3 on a free Ga5As+5 cationic cluster. J Chem Phys 1996. [DOI: 10.1063/1.470913] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
43
|
Nakamura J, Straub K, Wu J, Lou L. The glutamine hydrolysis function of human GMP synthetase. Identification of an essential active site cysteine. J Biol Chem 1995; 270:23450-5. [PMID: 7559506 DOI: 10.1074/jbc.270.40.23450] [Citation(s) in RCA: 31] [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: 01/25/2023] Open
Abstract
GMP synthetase (EC 6.3.5.2) is an amidotransferase that catalyzes the amination of xanthosine 5'-monophosphate to form GMP in the presence of glutamine and ATP. Glutamine hydrolysis produces the necessary amino group while ATP hydrolysis drives the reaction. Ammonia can also serve as an amino group donor. GMP synthetase contains two functional domains, which are well coordinated. The "glutamine amide transfer" or glutaminase domain is responsible for glutamine hydrolysis. The synthetase domain is responsible for ATP hydrolysis and GMP formation. Inorganic pyrophosphate inhibits the synthetase and uncouples the two domain functions by allowing glutamine hydrolysis to take place in the absence of ATP hydrolysis or GMP formation. Acivicin, a glutamine analog, selectively abolishes the glutaminase activity. It inhibits the synthetase activity only when glutamine is the amino donor. When ammonia is used in place of glutamine, acivicin has no effect on the synthetase activity. Acivicin inhibits GMP synthetase irreversibly by covalent modification. Enzyme inactivation is greatly facilitated by the presence of substrates. Acivicin labels GMP synthetase at a single site, and a tryptic peptide containing the modified residue was isolated. Mass spectrometry and Edman sequence analysis show that Cys104 is the site of modification. This residue is conserved among GMP synthetases and is located within a predicted glutamine amide transfer domain. These data suggest that Cys104 is an essential residue involved in the hydrolysis of glutamine to produce an amino group and is not needed for the hydrolysis of ATP or amination of xanthosine 5'-monophosphate to produce GMP.
Collapse
Affiliation(s)
- J Nakamura
- Institute of Biochemistry and Cell Biology, Syntex Discovery Research, Palo Alto, California 94303, USA
| | | | | | | |
Collapse
|
44
|
Rinzler AG, Hafner JH, Nikolaev P, Nordlander P, Colbert DT, Smalley RE, Lou L, Kim SG, Tománek D. Unraveling Nanotubes: Field Emission from an Atomic Wire. Science 1995; 269:1550-3. [PMID: 17789445 DOI: 10.1126/science.269.5230.1550] [Citation(s) in RCA: 1378] [Impact Index Per Article: 47.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Field emission of electrons from individually mounted carbon nanotubes has been found to be dramatically enhanced when the nanotube tips are opened by laser evaporation or oxidative etching. Emission currents of 0.1 to 1 microampere were readily obtained at room temperature with bias voltages of less than 80 volts. The emitting structures are concluded to be linear chains of carbon atoms, Cn, (n = 10 to 100), pulled out from the open edges of the graphene wall layers of the nanotube by the force of the electric field, in a process that resembles unraveling the sleeve of a sweater.
Collapse
|
45
|
Lou L, Bergson C, McGinnis W. Deformed expression in the Drosophila central nervous system is controlled by an autoactivated intronic enhancer. Nucleic Acids Res 1995; 23:3481-7. [PMID: 7567459 PMCID: PMC307227 DOI: 10.1093/nar/23.17.3481] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [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] [Indexed: 01/26/2023] Open
Abstract
Deformed (Dfd) is a Drosophila homeotic selector gene required for normal development of maxillary segment morphology in the larval and adult head. Consistent with this function, Dfd transcripts are restricted to epidermal, mesodermal and neural cells in the embryonic mandibular and maxillary primordia. Previous studies have identified a far upstream element in Dfd sequences which functions as an epidermal-specific autoregulatory enhancer. In a search through 35 kb of Dfd sequences for additional transcriptional control elements, we have identified a 3.2 kb DNA fragment containing an enhancer that mimics the expression of Dfd in the subesophageal ganglion of the embryonic central nervous system. This Neural autoregulatory enhancer (NAE) maps in the large Dfd intron just upstream of the homeobox exon and requires Dfd protein function for its full activity. A 608 bp NAE subfragment retains regulatory function that is principally localized in the subesophageal ganglion. This small region of the Drosophila melanogaster genome contains numerous blocks of sequence conservation with a comparable region from the Dfd locus of D.hydei. A pair of conserved blocks of NAE sequence match a Dfd protein binding site in the epidermal autoregulatory element, while another conserved sequence motif is repeated multiple times within the 608 bp subelement.
Collapse
Affiliation(s)
- L Lou
- Department of Pediatrics, Yale University, New Haven, CT 06520, USA
| | | | | |
Collapse
|
46
|
Abstract
Leflunomide [HWA 486 or RS-34821, 5-methyl-N-(4-trifluoromethylphenyl)-4-isoxazole carboximide] is an immunosuppressive agent effective in the treatment of rheumatoid arthritis. In spite of its clinical potential, its mechanism of action has not been elucidated. Recent studies suggest that leflunomide may interfere with the metabolism of pyrimidine nucleotides. In our studies, the active metabolite of leflunomide, RS-61980 (A77 1726, 2-hydroxyethylidene-cyanoacetic acid-4-trifluoromethyl anilide), was cytostatic towards a human T-lymphoblastoma cell line (A3.01). The inhibition of growth could be overcome completely by uridine. The other nucleosides, cytidine, adenosine and guanosine, did not overcome the effect of the compound. Since uridine is a precursor for the salvage synthesis of UMP, we propose that RS-61980 may be inhibiting the de novo pathway of UMP synthesis. Using human cells, the six enzymes catalyzing de novo UMP biosynthesis were tested for their sensitivity towards RS-61980. Only one of the enzymes, dihydroortate dehydrogenase (DHODH, EC 1.3.3.1) was inhibited by RS-61980 with a Ki value of 2.7 +/- 0.7 microM. The other five enzymes were not affected. The inhibition exhibited mixed-type kinetics towards both substrates, dihydroorotic acid and coenzyme Q. These results suggest that the molecular target of leflunomide action is DHODH. The immunomodulating activity may be related to the inhibition of UMP synthesis in proliferating lymphocytes.
Collapse
Affiliation(s)
- S Greene
- Institute of Biochemistry and Cell Biology, Syntex Discovery Research, Palo Alto, CA 94303, USA
| | | | | | | |
Collapse
|
47
|
Lou L, Nakamura J, Tsing S, Nguyen B, Chow J, Straub K, Chan H, Barnett J. High-level production from a baculovirus expression system and biochemical characterization of human GMP synthetase. Protein Expr Purif 1995; 6:487-95. [PMID: 8527935 DOI: 10.1006/prep.1995.1065] [Citation(s) in RCA: 14] [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] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
GMP synthetase, a key enzyme in the de novo synthesis of guanine nucleotides, is a potential target for immunosuppression and anticancer chemotherapy. In order to closely examine the catalytic mechanism and active-site topography of this enzyme, large amounts of pure protein are needed. Catalytically active human GMP synthetase was expressed in a baculovirus system. A high-level production system has been established from which the yield of pure protein is routinely more than 50 mg/10 liters of cell culture. The recombinant enzyme was purified to homogeneity and characterized. Like native GMP synthetase, the recombinant enzyme was resolved into two forms by ion-exchange chromatography. The two forms are both monomers and they differ in their isoelectric points. There is no evidence that these forms are in equilibrium or interconvertible. Protein sequence analysis reveals that both forms are blocked at the amino-terminus and they are essentially identical in sequence. Since they can be produced by a cDNA with a single open reading frame, we believe that they represent post-translational modification variants. The recombinant GMP synthetase is not distinguishable from the native enzyme in terms of chromatographic profiles, subunit composition, molecular weight, and kinetic properties. The inhibition constants and the modes of inhibition toward decoyinine, a selective inhibitor of GMP synthetase, are also the same as the native enzyme. The high-level production of active enzyme is invaluable to the determination of the three-dimensional structure and the discovery of potent and selective drug candidates.
Collapse
Affiliation(s)
- L Lou
- Institute of Biochemistry and Cell Biology, Syntex Discovery Research, Palo Alto, California 94304, USA
| | | | | | | | | | | | | | | |
Collapse
|
48
|
|
49
|
Mackey J, Lou L, Nordlander P. A density‐functional study of cluster reactivity. II. Two ammonia molecules reacting with a free Ga5As5 cluster. J Chem Phys 1995. [DOI: 10.1063/1.469061] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
50
|
Abstract
GMP synthetase (EC 6.3.5.2) plays a key role in the de novo synthesis of guanine nucleotides. It is a potential target for immunosuppressive therapy. Recently, the human enzyme was purified to homogeneity (Hirst, M., Haliday, E., Nakamura, J., and Lou, L. (1994) J. Biol. Chem. 269, 23830-23837). We now report the characterization of this enzyme in terms of its biochemical and kinetic properties. We found that there are distinct features of the human enzyme that has not been reported for GMP synthetase from other sources. There are two variant forms of human GMP synthetase. Their catalytic properties are very similar, although their isoelectric points are different. They most likely represent post-translational modification variants. Magnesium ion is required for enzyme activity, and the requirement is beyond levels needed for ATP chelation. Magnesium appears to be an essential activator and there may be more than one binding site. Interaction of GMP synthetase with xanthosine 5'-monophosphate (XMP), a substrate, exhibits sigmoidal kinetics with a Hill coefficient of 1.48 +/- 0.07. This positive cooperativity is not due to ligand-induced oligomerization, since GMP synthetase remains a monomer in the presence of XMP and other substrates. Decoyinine, a selective inhibitor of GMP synthetase, inhibits the human enzyme reversibly with uncompetitive inhibition kinetics toward glutamine and XMP and non-competitive kinetics toward ATP.
Collapse
Affiliation(s)
- J Nakamura
- Institute of Biochemistry and Cell Biology, Syntex Discovery Research, Palo Alto, California 94304, USA
| | | |
Collapse
|