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Joyeux L, van der Merwe J, Aertsen M, Patel PA, Khatoun A, Mori da Cunha MGMC, De Vleeschauwer S, Parra J, Danzer E, McLaughlin M, Stoyanov D, Vercauteren T, Ourselin S, Radaelli E, de Coppi P, Van Calenbergh F, Deprest J. Neuroprotection is improved by watertightness of fetal spina bifida repair in the sheep model. Ultrasound Obstet Gynecol 2023; 61:81-92. [PMID: 35353933 DOI: 10.1002/uog.24907] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 03/01/2022] [Accepted: 03/21/2022] [Indexed: 05/27/2023]
Abstract
OBJECTIVES A contributing factor to unsuccessful prenatal spina bifida aperta (SBA) repair via an open approach may be incomplete neurosurgical repair causing persistent in-utero leakage of cerebrospinal fluid (CSF) and exposure of the fetal spinal cord to amniotic fluid. We aimed to investigate the neurostructural and neurofunctional efficacy of watertight prenatal SBA repair in a validated SBA fetal lamb model. METHODS A well-powered superiority study was conducted in the validated SBA fetal lamb model (n = 7 per group). The outcomes of lambs which underwent watertight or non-watertight multilayer repair through an open approach were compared to those of unrepaired SBA lambs (historical controls) at delivery (term = 145 days). At ∼75 days, fetal lambs underwent standardized induction of lumbar SBA. At ∼100 days, they were assigned to an either watertight or non-watertight layered repair group based on an intraoperative watertightness test using subcutaneous fluorescein injection. At 1-2 days postnatally, as primary outcome, we assessed reversal of hindbrain herniation using magnetic resonance imaging (MRI). Secondary proxies of neuroprotection were: absence of CSF leakage at the repair site; hindlimb motor function based on joint-movement score, locomotor grade and Motor Evoked Potential (MEP); four-score neuroprotection scale, encompassing live birth, complete hindbrain herniation reversal, absence of CSF leakage and joint-movement score ≥ 9/15; and brain and spinal cord histology and immunohistochemistry. As the watertightness test cannot be used clinically due to its invasiveness, we developed a potential surrogate intraoperative three-score skin-repair-quality scale based on visual assessment of the quality of the skin repair (suture inter-run distance ≤ 3 mm, absence of tear and absence of ischemia), with high quality defined by a score ≥ 2/3 and low quality by a score < 2/3, and assessed its relationship with improved outcome. RESULTS Compared with unrepaired lambs, lambs with watertight repair achieved a high level of neuroprotection (neuroprotection score of 4/4 in 5/7 vs 0/7 lambs) as evidenced by: a significant 100% (vs 14%) reversal of hindbrain herniation on MRI; low CSF leakage (14% vs 100%); better hindlimb motor function, with higher joint-movement score, locomotor grade and MEP area under the curve and peak-to-peak amplitude; higher neuronal density in the hippocampus and corpus callosum; and higher reactive astrogliosis at the SBA lesion epicenter. Conversely, lambs with non-watertight SBA repair did not achieve the same level of neuroprotection (score of 4/4 in 1/7 lambs) compared with unrepaired lambs, with: a non-significant 86% (vs 14%) reversal of hindbrain herniation; high CSF leakage (43% vs 100%); no improvement in motor function; low brain neuron count in both the hippocampus and corpus callosum; and small spinal astroglial cell area at the epicenter. Both watertight layered repair and high (≥ 2/3) intraoperative skin-repair-quality score were associated with improved outcome, but the watertightness test and skin-repair-quality scale could not be used interchangeably due to result discrepancies. CONCLUSIONS Watertight layered fetal SBA repair is neuroprotective since it improves brain and spinal-cord structure and function in the fetal lamb model. This translational research has important clinical implications. A neurosurgical technique that achieves watertightness should be adopted in all fetal centers to improve neuroprotection. Future clinical studies could assess whether a high skin-repair-quality score (≥ 2/3) correlates with neuroprotection. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.
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Affiliation(s)
- L Joyeux
- My FetUZ Fetal Research Center, Department of Development and Regeneration, Biomedical Sciences, KU Leuven, Leuven, Belgium
- Center for Surgical Technologies, Faculty of Medicine, KU Leuven, Leuven, Belgium
- Department of Obstetrics and Gynecology, Division of Woman and Child, Fetal Medicine Unit, University Hospitals Leuven, Leuven, Belgium
- Department of Pediatric Surgery, Texas Children's Hospital and Baylor College of Medicine, Houston, TX, USA
| | - J van der Merwe
- My FetUZ Fetal Research Center, Department of Development and Regeneration, Biomedical Sciences, KU Leuven, Leuven, Belgium
- Center for Surgical Technologies, Faculty of Medicine, KU Leuven, Leuven, Belgium
- Department of Obstetrics and Gynecology, Division of Woman and Child, Fetal Medicine Unit, University Hospitals Leuven, Leuven, Belgium
| | - M Aertsen
- Department of Radiology, University Hospitals Leuven, Leuven, Belgium
| | - P A Patel
- Radiology Department, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, UK
| | - A Khatoun
- Exp ORL, Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - M G M C Mori da Cunha
- My FetUZ Fetal Research Center, Department of Development and Regeneration, Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - S De Vleeschauwer
- Animal Research Center, Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - J Parra
- My FetUZ Fetal Research Center, Department of Development and Regeneration, Biomedical Sciences, KU Leuven, Leuven, Belgium
- BCNatal, Fetal Medicine Research Center, Hospital Clinic and Hospital Sant Joan de Déu, University of Barcelona, Barcelona, Spain
| | - E Danzer
- Division of Pediatric Surgery, Lucile Packard Children's Hospital, Stanford University, Stanford, CA, USA
| | - M McLaughlin
- Radiology Department, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, UK
| | - D Stoyanov
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London, UK
| | - T Vercauteren
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
| | - S Ourselin
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
| | - E Radaelli
- Department of Pathobiology, Ryan Veterinary Hospital, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | - P de Coppi
- My FetUZ Fetal Research Center, Department of Development and Regeneration, Biomedical Sciences, KU Leuven, Leuven, Belgium
- Center for Surgical Technologies, Faculty of Medicine, KU Leuven, Leuven, Belgium
- Department of Obstetrics and Gynecology, Division of Woman and Child, Fetal Medicine Unit, University Hospitals Leuven, Leuven, Belgium
- Specialist Neonatal and Pediatric Surgery Unit, Great Ormond Street Hospital, University College London Hospitals, NHS Foundation Trust, London, UK
| | - F Van Calenbergh
- Department of Neurosurgery, University Hospitals Leuven, Leuven, Belgium
| | - J Deprest
- My FetUZ Fetal Research Center, Department of Development and Regeneration, Biomedical Sciences, KU Leuven, Leuven, Belgium
- Center for Surgical Technologies, Faculty of Medicine, KU Leuven, Leuven, Belgium
- Department of Obstetrics and Gynecology, Division of Woman and Child, Fetal Medicine Unit, University Hospitals Leuven, Leuven, Belgium
- Institute of Women's Health, University College London Hospitals, London, UK
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Purohit PB, Prakash Gupta J, Chaudhari JD, Bhatt TM, Pawar MM, Srivastava AK, Patel MP, Patel PA, Prajapat MN. Effect of heat stress on age at first calving in Mehsana buffaloes under field progeny testing programme. IJDS 2021. [DOI: 10.33785/ijds.2021.v74i04.005] [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: 11/23/2022]
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Patel KP, Patel PA, Vunnam SR, Jain R, Vunnam RR. Patients with COVID-19: are current isolation guidelines effective enough? Public Health 2020; 183:38-39. [PMID: 32417566 PMCID: PMC7211713 DOI: 10.1016/j.puhe.2020.04.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 04/25/2020] [Indexed: 02/07/2023]
Affiliation(s)
- K P Patel
- Department of Internal Medicine, University of Nebraska Medical Center College of Medicine, Omaha, NE, USA.
| | - P A Patel
- Nova Southeastern University Kiran C. Patel College of Osteopathic Medicine, Fort Lauderdale, FL, USA
| | - S R Vunnam
- Department of Internal Medicine, University of Nebraska Medical Center College of Medicine, Omaha, NE, USA
| | - R Jain
- Division of Hospital Medicine, Penn State Health Milton S. Hershey Medical Center, College of Medicine, Hershey, PA, USA
| | - R R Vunnam
- Division of Hospital Medicine, Penn State Health Milton S. Hershey Medical Center, College of Medicine, Hershey, PA, USA
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Patel PA, Liang C, Arora A, Vijayan S, Ahuja S, Wagley PK, Settlage R, LaConte LEW, Goodkin HP, Lazar I, Srivastava S, Mukherjee K. Haploinsufficiency of X-linked intellectual disability gene CASK induces post-transcriptional changes in synaptic and cellular metabolic pathways. Exp Neurol 2020; 329:113319. [PMID: 32305418 DOI: 10.1016/j.expneurol.2020.113319] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 04/04/2020] [Accepted: 04/15/2020] [Indexed: 12/17/2022]
Abstract
Heterozygous mutations in the X-linked gene CASK are associated with intellectual disability, microcephaly, pontocerebellar hypoplasia, optic nerve hypoplasia and partially penetrant seizures in girls. The Cask+/- heterozygous knockout female mouse phenocopies the human disorder and exhibits postnatal microencephaly, cerebellar hypoplasia and optic nerve hypoplasia. It is not known if Cask+/- mice also display seizures, nor is known the molecular mechanism by which CASK haploinsufficiency produces the numerous documented phenotypes. 24-h video electroencephalography demonstrates that despite sporadic seizure activity, the overall electrographic patterns remain unaltered in Cask+/- mice. Additionally, seizure threshold to the commonly used kindling agent, pentylenetetrazol, remains unaltered in Cask+/- mice, indicating that even in mice the seizure phenotype is only partially penetrant and may have an indirect mechanism. RNA sequencing experiments on Cask+/- mouse brain uncovers a very limited number of changes, with most differences arising in the transcripts of extracellular matrix proteins and the transcripts of a group of nuclear proteins. In contrast to limited changes at the transcript level, quantitative whole-brain proteomics using iTRAQ quantitative mass-spectrometry reveals major changes in synaptic, metabolic/mitochondrial, cytoskeletal, and protein metabolic pathways. Unbiased protein-protein interaction mapping using affinity chromatography demonstrates that CASK may form complexes with proteins belonging to the same functional groups in which altered protein levels are observed. We discuss the mechanism of the observed changes in the context of known molecular function/s of CASK. Overall, our data indicate that the phenotypic spectrum of female Cask+/- mice includes sporadic seizures and thus closely parallels that of CASK haploinsufficient girls; the Cask+/- mouse is thus a face-validated model for CASK-related pathologies. We therefore surmise that CASK haploinsufficiency is likely to affect brain structure and function due to dysregulation of several cellular pathways including synaptic signaling and cellular metabolism.
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Affiliation(s)
- P A Patel
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States; Graduate Program in Translational Biology, Medicine, and Health, Virginia Tech, Blacksburg, VA, United States
| | - C Liang
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States
| | - A Arora
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States
| | - S Vijayan
- School of Neuroscience, Virginia Tech, Blacksburg, VA, United States
| | - S Ahuja
- Biological Sciences, Virginia Tech, Blacksburg, VA, United States
| | - P K Wagley
- Neurology, University of Virginia, Charlottesville, VA, USA
| | - R Settlage
- Advanced Research Computing, Virginia Tech, Blacksburg, VA, United States
| | - L E W LaConte
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States
| | - H P Goodkin
- Neurology, University of Virginia, Charlottesville, VA, USA
| | - I Lazar
- Biological Sciences, Virginia Tech, Blacksburg, VA, United States
| | - S Srivastava
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States
| | - K Mukherjee
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States; Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States; Department of Psychiatry and Behavioral Medicine, Virginia Tech Carilion School of Medicine, Roanoke, VA, United States.
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Chowdhary A, Nadarajah R, Hammond C, Burnett N, Mwambingu T, Artis N, Patel PA. P796 Feasibility of exercise stress echocardiography and its correlation with angiographically significant coronary disease. Eur Heart J Cardiovasc Imaging 2020. [DOI: 10.1093/ehjci/jez319.452] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
European Society of Cardiology (ESC) guidelines on the management of stable coronary artery disease (CAD) advocate stress echocardiography (SE) as a first line assessment for functionally significant ischaemia. Pharmacological stressors such as dobutamine are typically utilised in most UK centres in view of practical benefits when compared with treadmill testing. However, exercise provides the best physiological mimic and enables additional data on haemodynamics and electrocardiogram (ECG) changes to be obtained.
Purpose
To assess the feasibility and safety of exercise stress echocardiography (ESE), and the correlation of positive testing with significant coronary disease and major adverse cardiovascular events.
Methods
A retrospective, single-centre analysis of 500 consecutive patients undergoing ESE for investigation of stable CAD. Cases were excluded when a pharmacological stressor was utilised, or in contexts where ESE was performed for other clinical indications. ESE reports were interrogated for patient demographics, co-morbidities, achievement of target heart rate (HR), procedural sequelae, image quality and findings. Electronic records were reviewed after 24 months to assess results of invasive angiography, when performed, and long-term outcomes including myocardial infarction (MI) and cardiovascular mortality. Concordance between ischaemic territory on ESE and coronary lesions on angiography was also collated.
Results
95% (475/500) of patients were suitable for inclusion. Of these, 83% (394/475) achieved target HR. Sequelae arose in 0.02% (9/475), with the most frequent being ectopy (4 cases). Image quality was adequate in 98% (465/475), with the requirement for contrast agent in the remainder. There were no significant differences in burden of cardiovascular risk factors between the positive and negative ESE groups. 13% (63/475) were positive for inducible ischaemia in one or more myocardial segments. Of these, 71% (45/65) underwent angiography, with 48% (31/65) requiring stenting or bypass surgery. Ischaemic territory on ESE correlated with angiographic lesions in 65% (29/45) of cases. ESE underestimated extent of significant CAD in only 7% (3/45). In the subcohort positive for ESE, 3% (2/63) suffered a MI and cardiovascular mortality was 1.5% (1/63).
Conclusions
ESE is a safe, non-invasive modality for functional testing that reaches diagnostic threshold in the vast majority of cases. It has reasonable concordance in localising ischaemic coronary territory to enable targeted revascularisation.
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Affiliation(s)
- A Chowdhary
- University of Leeds, Leeds, United Kingdom of Great Britain & Northern Ireland
| | - R Nadarajah
- Pinderfields General Hospital, Wakefield, United Kingdom of Great Britain & Northern Ireland
| | - C Hammond
- Pinderfields General Hospital, Wakefield, United Kingdom of Great Britain & Northern Ireland
| | - N Burnett
- Pinderfields General Hospital, Wakefield, United Kingdom of Great Britain & Northern Ireland
| | - T Mwambingu
- Pinderfields General Hospital, Wakefield, United Kingdom of Great Britain & Northern Ireland
| | - N Artis
- Pinderfields General Hospital, Wakefield, United Kingdom of Great Britain & Northern Ireland
| | - P A Patel
- Leeds Teaching Hospitals NHS Trust, Leeds, United Kingdom of Great Britain & Northern Ireland
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Qureshi AM, Davies LK, Patel PA, Rennie A, Robertson F. Determinants of Radiation Dose in Selective Ophthalmic Artery Chemosurgery for Retinoblastoma. AJNR Am J Neuroradiol 2019; 40:713-717. [PMID: 30872423 DOI: 10.3174/ajnr.a6000] [Citation(s) in RCA: 1] [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: 10/30/2018] [Accepted: 01/25/2019] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Retinoblastoma is the most common pediatric ocular neoplasm. Multimodality treatment approaches are commonplace, and selective ophthalmic artery chemosurgery has emerged as a safe and effective treatment in selected patients. Minimizing radiation dose in this highly radiosensitive patient cohort is critical. We explore which procedural factors affect the radiation dose in a single-center cohort of children managed in the UK National Retinoblastoma Service. MATERIALS AND METHODS A retrospective review was performed of 177 selective ophthalmic artery chemosurgery procedures in 48 patients with retinoblastoma (2013-2017). Medical records, angiographic imaging, and radiation dosimetry data (including total fluoroscopic screening time, skin dose, and dose-area product) were reviewed. RESULTS The mean fluoroscopic time was 13.5 ± 13 minutes, the mean dose-area product was 11.7 ± 9.7 Gy.cm2, and the mean total skin dose was 260.9 ± 211.6 mGy. One hundred sixty-three of 177 procedures (92.1%) were technically successful. In 14 (7.9%), the initial attempt was unsuccessful (successful in 13/14 re-attempts). Screening time and radiation dose were associated with drug-delivery microcatheter location and patient age; screening time was associated with treatment cycle. CONCLUSIONS In selective ophthalmic artery chemosurgery, a microcatheter tip position in the proximal or ostial ophthalmic artery and patient age 2 years or younger were associated with reduced fluoroscopic screening time and radiation dose; treatment beyond the first cycle was associated with reduced fluoroscopic screening time.
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Affiliation(s)
- A M Qureshi
- From the Department of Radiology, Great Ormond Street Hospital for Children, National Health Service Foundation Trust, London, UK
| | - L K Davies
- From the Department of Radiology, Great Ormond Street Hospital for Children, National Health Service Foundation Trust, London, UK
| | - P A Patel
- From the Department of Radiology, Great Ormond Street Hospital for Children, National Health Service Foundation Trust, London, UK
| | - A Rennie
- From the Department of Radiology, Great Ormond Street Hospital for Children, National Health Service Foundation Trust, London, UK
| | - F Robertson
- From the Department of Radiology, Great Ormond Street Hospital for Children, National Health Service Foundation Trust, London, UK.
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Abbott JR, Patel PA, Howes JE, Akan DT, Kennedy JP, Burns MC, Browning CF, Sun Q, Rossanese OW, Phan J, Waterson AG, Fesik SW. Discovery of Quinazolines That Activate SOS1-Mediated Nucleotide Exchange on RAS. ACS Med Chem Lett 2018; 9:941-946. [PMID: 30258545 DOI: 10.1021/acsmedchemlett.8b00296] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 08/08/2018] [Indexed: 12/13/2022] Open
Abstract
Proteins in the RAS family are important regulators of cellular signaling and, when mutated, can drive cancer pathogenesis. Despite considerable effort over the last 30 years, RAS proteins have proven to be recalcitrant therapeutic targets. One approach for modulating RAS signaling is to target proteins that interact with RAS, such as the guanine nucleotide exchange factor (GEF) son of sevenless homologue 1 (SOS1). Here, we report hit-to-lead studies on quinazoline-containing compounds that bind to SOS1 and activate nucleotide exchange on RAS. Using structure-based design, we refined the substituents attached to the quinazoline nucleus and built in additional interactions not present in the initial HTS hit. Optimized compounds activate nucleotide exchange at single-digit micromolar concentrations in vitro. In HeLa cells, these quinazolines increase the levels of RAS-GTP and cause signaling changes in the mitogen-activated protein kinase/extracellular regulated kinase (MAPK/ERK) pathway.
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Affiliation(s)
- Jason R. Abbott
- Department of Biochemistry and ‡Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
| | - Pratiq A. Patel
- Department of Biochemistry and ‡Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
| | - Jennifer E. Howes
- Department of Biochemistry and ‡Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
| | - Denis T. Akan
- Department of Biochemistry and ‡Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
| | - J. Phillip Kennedy
- Department of Biochemistry and ‡Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
| | - Michael C. Burns
- Department of Biochemistry and ‡Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
| | - Carrie F. Browning
- Department of Biochemistry and ‡Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
| | - Qi Sun
- Department of Biochemistry and ‡Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
| | - Olivia W. Rossanese
- Department of Biochemistry and ‡Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
| | - Jason Phan
- Department of Biochemistry and ‡Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
| | - Alex G. Waterson
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232-0146, United States
| | - Stephen W. Fesik
- Department of Biochemistry and ‡Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232-0146, United States
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Abbott JR, Hodges TR, Daniels RN, Patel PA, Kennedy JP, Howes JE, Akan DT, Burns MC, Sai J, Sobolik T, Beesetty Y, Lee T, Rossanese OW, Phan J, Waterson AG, Fesik SW. Discovery of Aminopiperidine Indoles That Activate the Guanine Nucleotide Exchange Factor SOS1 and Modulate RAS Signaling. J Med Chem 2018; 61:6002-6017. [PMID: 29856609 DOI: 10.1021/acs.jmedchem.8b00360] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [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: 11/28/2022]
Abstract
Deregulated RAS activity, often the result of mutation, is implicated in approximately 30% of all human cancers. Despite this statistic, no clinically successful treatment for RAS-driven tumors has yet been developed. One approach for modulating RAS activity is to target and affect the activity of proteins that interact with RAS, such as the guanine nucleotide exchange factor (GEF) son of sevenless homologue 1 (SOS1). Here, we report on structure-activity relationships (SAR) in an indole series of compounds. Using structure-based design, we systematically explored substitution patterns on the indole nucleus, the pendant amino acid moiety, and the linker unit that connects these two fragments. Best-in-class compounds activate the nucleotide exchange process at submicromolar concentrations in vitro, increase levels of active RAS-GTP in HeLa cells, and elicit signaling changes in the mitogen-activated protein kinase-extracellular regulated kinase (MAPK-ERK) pathway, resulting in a decrease in pERK1/2T202/Y204 protein levels at higher compound concentrations.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Alex G Waterson
- Department of Chemistry , Vanderbilt University , Nashville , Tennessee 37232-0146 , United States
| | - Stephen W Fesik
- Department of Chemistry , Vanderbilt University , Nashville , Tennessee 37232-0146 , United States
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Woodard JL, Huntsman AC, Patel PA, Chai HB, Kanagasabai R, Karmahapatra S, Young AN, Ren Y, Cole MS, Herrera D, Yalowich JC, Kinghorn AD, Burdette JE, Fuchs JR. Synthesis and antiproliferative activity of derivatives of the phyllanthusmin class of arylnaphthalene lignan lactones. Bioorg Med Chem 2018; 26:2354-2364. [PMID: 29656990 DOI: 10.1016/j.bmc.2018.03.033] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 03/14/2018] [Accepted: 03/21/2018] [Indexed: 01/08/2023]
Abstract
A series of arylnaphthalene lignan lactones based on the structure of the phyllanthusmins, a class of potent natural products possessing diphyllin as the aglycone, has been synthesized and screened for activity against multiple cancer cell lines. SAR exploration was performed on both the carbohydrate and lactone moieties of this structural class. These studies have revealed the importance of functionalization of the carbohydrate hydroxy groups with both acetylated and methylated analogues showing increased potency relative to those with unsubstituted sugar moieties. In addition, the requirement for the presence and position of the C-ring lactone has been demonstrated through reduction and selective re-oxidation of the lactone ring. The most potent compound in this study displayed an IC50 value of 18 nM in an HT-29 assay with several others ranging from 50 to 200 nM. In an effort to elucidate their potential mechanism(s) of action, the DNA topoisomerase IIa inhibitory activity of the most potent compounds was examined based on previous reports of structurally similar compounds, but does not appear to contribute significantly to their antiproliferative effects.
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Affiliation(s)
- John L Woodard
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Andrew C Huntsman
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Pratiq A Patel
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Hee-Byung Chai
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Ragu Kanagasabai
- Division of Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | | | - Alexandria N Young
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois-Chicago, Chicago, IL 60612, United States
| | - Yulin Ren
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Malcolm S Cole
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Denisse Herrera
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois-Chicago, Chicago, IL 60612, United States
| | - Jack C Yalowich
- Division of Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - A Douglas Kinghorn
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Joanna E Burdette
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois-Chicago, Chicago, IL 60612, United States
| | - James R Fuchs
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States.
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Smith FGD, Patel PA, Santhalingam M, Nayar V. 140A retrospective study to assess feasibility of daycase complex device insertion. Europace 2017. [DOI: 10.1093/europace/eux283.132] [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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Smith FGD, Patel PA, Santhalingam M, Nayar V. 137Do octogenarians tolerate CRT-P insertion? Europace 2017. [DOI: 10.1093/europace/eux283.129] [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: 11/14/2022] Open
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12
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Patel PA, Kvaratskhelia N, Mansour Y, Antwi J, Feng L, Koneru P, Kobe MJ, Jena N, Shi G, Mohamed MS, Li C, Kessl JJ, Fuchs JR. Indole-based allosteric inhibitors of HIV-1 integrase. Bioorg Med Chem Lett 2016; 26:4748-4752. [PMID: 27568085 DOI: 10.1016/j.bmcl.2016.08.037] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/11/2016] [Accepted: 08/12/2016] [Indexed: 11/15/2022]
Abstract
Employing a scaffold hopping approach, a series of allosteric HIV-1 integrase (IN) inhibitors (ALLINIs) have been synthesized based on an indole scaffold. These compounds incorporate the key elements utilized in quinoline-based ALLINIs for binding to the IN dimer interface at the principal LEDGF/p75 binding pocket. The most potent of these compounds displayed good activity in the LEDGF/p75 dependent integration assay (IC50=4.5μM) and, as predicted based on the geometry of the five- versus six-membered ring, retained activity against the A128T IN mutant that confers resistance to many quinoline-based ALLINIs.
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Affiliation(s)
- Pratiq A Patel
- Division of Medicinal Chemistry & Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States; Department of Chemistry, The Ohio State University, Columbus, OH 43210, United States
| | - Nina Kvaratskhelia
- Division of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Yara Mansour
- Division of Medicinal Chemistry & Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States; Pharmaceutical Organic Chemistry Department, Faculty of Pharmacy, Helwan University, Cairo, Egypt
| | - Janet Antwi
- Division of Medicinal Chemistry & Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Lei Feng
- Division of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Pratibha Koneru
- Division of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Mathew J Kobe
- Division of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Nivedita Jena
- Division of Medicinal Chemistry & Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Guqin Shi
- Division of Medicinal Chemistry & Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Mosaad S Mohamed
- Pharmaceutical Organic Chemistry Department, Faculty of Pharmacy, Helwan University, Cairo, Egypt
| | - Chenglong Li
- Division of Medicinal Chemistry & Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
| | - Jacques J Kessl
- Division of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States.
| | - James R Fuchs
- Division of Medicinal Chemistry & Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States.
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13
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Slaughter A, Jurado KA, Deng N, Feng L, Kessl JJ, Shkriabai N, Larue RC, Fadel HJ, Patel PA, Jena N, Fuchs JR, Poeschla E, Levy RM, Engelman A, Kvaratskhelia M. The mechanism of H171T resistance reveals the importance of Nδ-protonated His171 for the binding of allosteric inhibitor BI-D to HIV-1 integrase. Retrovirology 2014; 11:100. [PMID: 25421939 PMCID: PMC4251946 DOI: 10.1186/s12977-014-0100-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 10/24/2014] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Allosteric HIV-1 integrase (IN) inhibitors (ALLINIs) are an important new class of anti-HIV-1 agents. ALLINIs bind at the IN catalytic core domain (CCD) dimer interface occupying the principal binding pocket of its cellular cofactor LEDGF/p75. Consequently, ALLINIs inhibit HIV-1 IN interaction with LEDGF/p75 as well as promote aberrant IN multimerization. Selection of viral strains emerging under the inhibitor pressure has revealed mutations at the IN dimer interface near the inhibitor binding site. RESULTS We have investigated the effects of one of the most prevalent substitutions, H171T IN, selected under increasing pressure of ALLINI BI-D. Virus containing the H171T IN substitution exhibited an ~68-fold resistance to BI-D treatment in infected cells. These results correlated with ~84-fold reduced affinity for BI-D binding to recombinant H171T IN CCD protein compared to its wild type (WT) counterpart. However, the H171T IN substitution only modestly affected IN-LEDGF/p75 binding and allowed HIV-1 containing this substitution to replicate at near WT levels. The x-ray crystal structures of BI-D binding to WT and H171T IN CCD dimers coupled with binding free energy calculations revealed the importance of the Nδ- protonated imidazole group of His171 for hydrogen bonding to the BI-D tert-butoxy ether oxygen and establishing electrostatic interactions with the inhibitor carboxylic acid, whereas these interactions were compromised upon substitution to Thr171. CONCLUSIONS Our findings reveal a distinct mechanism of resistance for the H171T IN mutation to ALLINI BI-D and indicate a previously undescribed role of the His171 side chain for binding the inhibitor.
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Affiliation(s)
- Alison Slaughter
- Center for Retrovirus Research and Comprehensive Cancer Center, College of Pharmacy, The Ohio State University, 496 W. 12th Ave, 508 Riffe Building, Columbus, OH 43210 USA
| | - Kellie A Jurado
- Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute and Department of Medicine, Harvard Medical School, Boston, MA 02215 USA
| | - Nanjie Deng
- Department of Chemistry and Center for Biophysics and Computational Biology, College of Science and Technology, Temple University, Philadelphia, PA 19122 USA
| | - Lei Feng
- Center for Retrovirus Research and Comprehensive Cancer Center, College of Pharmacy, The Ohio State University, 496 W. 12th Ave, 508 Riffe Building, Columbus, OH 43210 USA
| | - Jacques J Kessl
- Center for Retrovirus Research and Comprehensive Cancer Center, College of Pharmacy, The Ohio State University, 496 W. 12th Ave, 508 Riffe Building, Columbus, OH 43210 USA
| | - Nikoloz Shkriabai
- Center for Retrovirus Research and Comprehensive Cancer Center, College of Pharmacy, The Ohio State University, 496 W. 12th Ave, 508 Riffe Building, Columbus, OH 43210 USA
| | - Ross C Larue
- Center for Retrovirus Research and Comprehensive Cancer Center, College of Pharmacy, The Ohio State University, 496 W. 12th Ave, 508 Riffe Building, Columbus, OH 43210 USA
| | - Hind J Fadel
- Department of Molecular Medicine & Division of Infectious Diseases, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
| | - Pratiq A Patel
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210 USA
| | - Nivedita Jena
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210 USA
| | - James R Fuchs
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210 USA
| | - Eric Poeschla
- Department of Molecular Medicine & Division of Infectious Diseases, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
| | - Ronald M Levy
- Department of Chemistry and Center for Biophysics and Computational Biology, College of Science and Technology, Temple University, Philadelphia, PA 19122 USA
| | - Alan Engelman
- Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute and Department of Medicine, Harvard Medical School, Boston, MA 02215 USA
| | - Mamuka Kvaratskhelia
- Center for Retrovirus Research and Comprehensive Cancer Center, College of Pharmacy, The Ohio State University, 496 W. 12th Ave, 508 Riffe Building, Columbus, OH 43210 USA
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Patel PA, Ravi KA, Ripley DP, Kane J, Wass E, Carr A, Wilson D, Watchorn N, Hobman RK, Gill D, Brooksby WP, Kilcullen N, Artis N. Clinician referrals for stress echocardiography: are we compliant with the NICE guidelines? Echo Res Pract 2014; 1:17-21. [PMID: 26693288 PMCID: PMC4676440 DOI: 10.1530/erp-14-0028] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 05/14/2014] [Accepted: 07/09/2014] [Indexed: 11/25/2022] Open
Abstract
Accurate diagnosis of stable angina is of paramount importance, and where possible, this should be based on clinical history. In cases of uncertainty, the National Institute for Health and Care Excellence (NICE) provides a framework for assisting diagnosis based on pre-test likelihood (PTL) of coronary artery disease. Functional testing such as stress echocardiography (SE) is recommended as a first-line investigation in patients with PTL of 30–60%. This study evaluated hospital clinicians' adherence to this recommendation. A prospective analysis of patients referred for SE at a district general hospital between March and May 2013 was performed. Data were extracted from an electronic database of SE reports and medical notes. A total of 193 patients were assessed. The most common PTL was 61–90%, accounting for 40% of the cohort. Of them, 14% had a PTL of 30–60%. Of these, 15% had positive SE; 57% described non-anginal pain, as defined by NICE, of whom only nine cases had SE positivity. None of these patients required revascularisation. Findings suggest that SE is being used in a much broader selection group than advocated by NICE. This may often be for its exclusion value rather than to stratify risk. Although utility may be justified in high-risk patients to avoid proceeding directly to invasive angiography, SE appears to add little in those with non-anginal pain and with low PTL. Greater focus should be directed towards characterisation of symptoms, which may negate the need for subsequent investigation.
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Affiliation(s)
- P A Patel
- Correspondence should be addressed to P A Patel
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Abstract
Objectives To review the systemic impact of smoking on bone healing as evidenced
within the orthopaedic literature. Methods A protocol was established and studies were sourced from five
electronic databases. Screening, data abstraction and quality assessment
was conducted by two review authors. Prospective and retrospective
clinical studies were included. The primary outcome measures were
based on clinical and/or radiological indicators of bone healing.
This review specifically focused on non-spinal orthopaedic studies. Results Nine tibia studies and eight other orthopaedic studies were considered
for systematic review. Of these 17 studies, 13 concluded that smoking
negatively influenced bone healing. Conclusions Smoking has a negative effect on bone healing, in terms of delayed
union, nonunion and more complications.
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Affiliation(s)
- R A Patel
- King's College London Dental Institute, Departmentof Periodontology, Guy's Hospital Campus, LondonSE1 9RT, UK
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Sandoe JAT, Patel PA, Baig MW, West R. What is the effect of penicillin dosing interval on outcomes in streptococcal infective endocarditis? J Antimicrob Chemother 2013; 68:2660-3. [PMID: 23766487 DOI: 10.1093/jac/dkt236] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES Penicillin is an important treatment option for streptococcal infective endocarditis (IE), but its short half-life requires frequent re-dosing (4- or 6-hourly). There is a variation between the dosing regimens in different guidelines and consequent differences in the dosing interval. The objective of this study was to examine the relationship between the penicillin dosing interval and outcomes in streptococcal IE. METHODS A retrospective study of cases of streptococcal IE was undertaken using the Leeds Endocarditis Service database. Cases were included if the first-line therapy had been penicillin and excluded if patients had received less than 72 h of therapy. Details of antimicrobial therapy and outcomes were collated using strict definitions. Various parameters were considered as independent variables in a multivariate logistic regression analysis. Univariate analysis of categorical data was carried out using a χ(2) test, and analysis of continuous data using an unpaired t-test. RESULTS Two hundred and twelve cases were included in the final analysis. Of the parameters considered, a 4-hourly dosing interval [unadjusted OR = 2.79 (95% CI 1.43-5.62)] and initial echocardiographic evidence of abscess or severe valve regurgitation [unadjusted OR = 0.30 (95% CI 0.13-0.66)] were the only statistically significant factors associated with the success or failure of penicillin therapy. The odds of a successful outcome were almost three times greater with a 4-hourly regimen than with a 6-hourly regimen. Failure of penicillin therapy had no correlation with the MIC of penicillin or the concurrent administration of gentamicin. CONCLUSIONS Penicillin continues to be an effective therapy for IE. This study suggests that a 4-hourly dosing interval may be relevant in predicting the success of initial medical therapy. Further prospective studies are warranted to evaluate relationships in more detail.
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Affiliation(s)
- J A T Sandoe
- Department of Microbiology, Leeds Teaching Hospitals NHS Trust, Great George Street, Leeds LS1 3EX, UK
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17
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Feng L, Sharma A, Slaughter A, Jena N, Koh Y, Shkriabai N, Larue RC, Patel PA, Mitsuya H, Kessl JJ, Engelman A, Fuchs JR, Kvaratskhelia M. The A128T resistance mutation reveals aberrant protein multimerization as the primary mechanism of action of allosteric HIV-1 integrase inhibitors. J Biol Chem 2013; 288:15813-20. [PMID: 23615903 DOI: 10.1074/jbc.m112.443390] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [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: 01/12/2023] Open
Abstract
Allosteric HIV-1 integrase (IN) inhibitors (ALLINIs) are a very promising new class of anti-HIV-1 agents that exhibit a multimodal mechanism of action by allosterically modulating IN multimerization and interfering with IN-lens epithelium-derived growth factor (LEDGF)/p75 binding. Selection of viral strains under ALLINI pressure has revealed an A128T substitution in HIV-1 IN as a primary mechanism of resistance. Here, we elucidated the structural and mechanistic basis for this resistance. The A128T substitution did not affect the hydrogen bonding between ALLINI and IN that mimics the IN-LEDGF/p75 interaction but instead altered the positioning of the inhibitor at the IN dimer interface. Consequently, the A128T substitution had only a minor effect on the ALLINI IC50 values for IN-LEDGF/p75 binding. Instead, ALLINIs markedly altered the multimerization of IN by promoting aberrant higher order WT (but not A128T) IN oligomers. Accordingly, WT IN catalytic activities and HIV-1 replication were potently inhibited by ALLINIs, whereas the A128T substitution in IN resulted in significant resistance to the inhibitors both in vitro and in cell culture assays. The differential multimerization of WT and A128T INs induced by ALLINIs correlated with the differences in infectivity of HIV-1 progeny virions. We conclude that ALLINIs primarily target IN multimerization rather than IN-LEDGF/p75 binding. Our findings provide the structural foundations for developing improved ALLINIs with increased potency and decreased potential to select for drug resistance.
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Affiliation(s)
- Lei Feng
- Center for Retrovirus Research, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, USA
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18
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Wang H, Jurado KA, Wu X, Shun MC, Li X, Ferris AL, Smith SJ, Patel PA, Fuchs JR, Cherepanov P, Kvaratskhelia M, Hughes SH, Engelman A. HRP2 determines the efficiency and specificity of HIV-1 integration in LEDGF/p75 knockout cells but does not contribute to the antiviral activity of a potent LEDGF/p75-binding site integrase inhibitor. Nucleic Acids Res 2012; 40:11518-30. [PMID: 23042676 PMCID: PMC3526291 DOI: 10.1093/nar/gks913] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [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] [Indexed: 02/07/2023] Open
Abstract
The binding of integrase (IN) to lens epithelium-derived growth factor (LEDGF)/p75 in large part determines the efficiency and specificity of HIV-1 integration. However, a significant residual preference for integration into active genes persists in Psip1 (the gene that encodes for LEDGF/p75) knockout (KO) cells. One other cellular protein, HRP2, harbors both the PWWP and IN-binding domains that are important for LEDGF/p75 co-factor function. To assess the role of HRP2 in HIV-1 integration, cells generated from Hdgfrp2 (the gene that encodes for HRP2) and Psip1/Hdgfrp2 KO mice were infected alongside matched control cells. HRP2 depleted cells supported normal infection, while disruption of Hdgfrp2 in Psip1 KO cells yielded additional defects in the efficiency and specificity of integration. These deficits were largely restored by ectopic expression of either LEDGF/p75 or HRP2. The double-KO cells nevertheless supported residual integration into genes, indicating that IN and/or other host factors contribute to integration specificity in the absence of LEDGF/p75 and HRP2. Psip1 KO significantly increased the potency of an allosteric inhibitor that binds the LEDGF/p75 binding site on IN, a result that was not significantly altered by Hdgfrp2 disruption. These findings help to rule out the host factor-IN interactions as the primary antiviral targets of LEDGF/p75-binding site IN inhibitors.
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Affiliation(s)
- Hao Wang
- Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
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19
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Chen PC, Wharton RE, Patel PA, Oyelere AK. Direct diazo-transfer reaction on beta-lactam: synthesis and preliminary biological activities of 6-triazolylpenicillanic acids. Bioorg Med Chem 2007; 15:7288-300. [PMID: 17855098 PMCID: PMC2755539 DOI: 10.1016/j.bmc.2007.08.035] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [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: 06/18/2007] [Revised: 08/14/2007] [Accepted: 08/20/2007] [Indexed: 11/30/2022]
Abstract
In this study we report the first example of a direct diazo-transfer reaction on readily available 6-aminopenicillanates to give 6-azidopenicillanates in high yield. Subsequent Cu(I)-catalyzed Huisgen cycloaddition between these 6-azidopenicillanates and assorted terminal alkynes facilely furnished 6-triazolylpenicillanic acids. Preliminary biological screening indicates that these triazolylpenicillanic acids possess low to moderate antibacterial activities.
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Affiliation(s)
- Po C Chen
- School of Chemistry and Biochemistry, Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA 30332-0400, USA
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20
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Lane DA, Patel PA, Morgan MM. Evidence for an intrinsic mechanism of antinociceptive tolerance within the ventrolateral periaqueductal gray of rats. Neuroscience 2005; 135:227-34. [PMID: 16084660 DOI: 10.1016/j.neuroscience.2005.06.014] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [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: 11/22/2004] [Revised: 04/22/2005] [Accepted: 06/09/2005] [Indexed: 11/26/2022]
Abstract
Repeated microinjections of morphine into the ventrolateral periaqueductal gray produce antinociceptive tolerance. This tolerance may be a direct effect of morphine on cells within the ventrolateral periaqueductal gray or may require activation of downstream structures such as the rostral ventromedial medulla or spinal cord. Experiment 1 examined whether tolerance develops when opioid receptors in the ventrolateral periaqueductal gray are blocked prior to repeated systemic morphine administration. Microinjections of naltrexone hydrochloride (1microg/0.4microl) into the ventrolateral periaqueductal gray blocked antinociception and significantly attenuated the development of antinociceptive tolerance produced from systemic morphine administration. Experiment 2 examined whether tolerance develops when the effects of morphine are isolated to the ventrolateral periaqueductal gray. This was accomplished by microinjecting morphine (5microg/0.4microl) into the ventrolateral periaqueductal gray while simultaneously blocking the descending output through the rostral ventromedial medulla. Inhibition of neurons within the rostral ventromedial medulla by microinjecting the GABA(A) agonist muscimol (10ng/0.5microl) blocked the antinociception produced by microinjection of morphine into the ventrolateral periaqueductal gray but did not block the development of tolerance. These data demonstrate that the ventrolateral periaqueductal gray is both necessary and sufficient to produce tolerance to the antinociceptive effect of morphine. The ventrolateral periaqueductal gray is necessary in that tolerance does not develop if opiate action within the ventrolateral periaqueductal gray is blocked (experiment 1). The ventrolateral periaqueductal gray is sufficient in that tolerance occurs even when morphine's effects are restricted to the ventrolateral periaqueductal gray (experiment 2).
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Affiliation(s)
- D A Lane
- Washington State University Vancouver, 14204 Northeast Salmon Creek Avenue, Vancouver, WA 98686, USA
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21
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Abstract
OBJECTIVE To evaluate the predictive accuracy of the severity of illness scoring systems in a single institution. DESIGN A prospective study conducted by collecting data on consecutive patients admitted to the medical intensive care unit over 20 months. Surgical and coronary care admissions were excluded. SETTING Veterans Affairs Medical Center at Buffalo, New York. PATIENTS AND PARTICIPANTS Data collected on 302 unique, consecutive patients admitted to the medical intensive care unit. INTERVENTIONS None. MEASUREMENTS AND RESULTS Data required to calculate the patients' predicted mortality by the Mortality Probability Model (MPM) II, Acute Physiology and Chronic Health Evaluation (APACHE) II and Simplified Acute Physiology Score (SAPS) II scoring systems were collected. The probability of mortality for the cohort of patients was analyzed using confidence interval analyses, receiver operator characteristic (ROC) curves, two by two contingency tables and the Lemeshow-Hosmer chi-square statistic. Predicted mortality for all three scoring systems lay within the 95 % confidence interval for actual mortality. For the MPM II, SAPS II and APACHE II, the c-index (equivalent to the area under the ROC curve) was 0.695 +/- 0.0307 SE, 0.702 +/- 0.063 SE and 0.672 +/- 0.0306 SE, respectively, which were not statistically different from each other but were lower than values obtained in previous studies. CONCLUSION Although the overall mortality was consistent with the predicted mortality, the poor fit of the data to the model impairs the validity of the result. The observed outcome could be due to erratic quality of care, or differences between the study population and the patient population in the original studies. The data cannot be used to distinguish between these possibilities. To increase predictive accuracy when studying individual intensive care units and enhance quality of care assessments it may be necessary to adapt the model to the patient population.
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Affiliation(s)
- P A Patel
- Division of Pulmonary and Critical Care Medicine, Veterans Affairs Health Care System of Western New York, State University of New York at Buffalo, New York, USA
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Patel PA, Valvano JW, Pearce JA, Prahl SA, Denham CR. A self-heated thermistor technique to measure effective thermal properties from the tissue surface. J Biomech Eng 1987; 109:330-5. [PMID: 3695434 DOI: 10.1115/1.3138689] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.2] [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: 01/07/2023]
Abstract
A microcomputer based instrument to measure effective thermal conductivity and diffusivity at the surface of a tissue has been developed. Self-heated spherical thermistors, partially embedded in an insulator, are used to simultaneously heat tissue and measure the resulting temperature rise. The temperature increase of the thermistor for a given applied power is a function of the combined thermal properties of the insulator, the thermistor, and the tissue. Once the probe is calibrated, the instrument accurately measures the thermal properties of tissue. Conductivity measurements are accurate to 2 percent and diffusivity measurements are accurate to 4 percent. A simplified bioheat equation is used which assumes the effective tissue thermal conductivity is a linear function of perfusion. Since tissue blood flow strongly affects heat transfer, the surface thermistor probe is quite sensitive to perfusion.
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Affiliation(s)
- P A Patel
- Department of Electrical and Computer Engineering, University of Texas at Austin 78712
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23
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Patel PA, Yoonessi S, O'Malley J, Freeman A, Gershon A, Ogra PL. Cell-mediated immunity to varicella-zoster virus infection in subjects with lymphoma or leukemia. J Pediatr 1979; 94:223-30. [PMID: 762611 DOI: 10.1016/s0022-3476(79)80828-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Normal subjects and patients with lymphoma or leukemia were tested for the levels of lymphocytes, E-rosette--forming T-cells, serum and vesicle fluid interferon, and specific in vitro proliferative response to varicella-zoster antigen after clinical varicella or herpes zoster illness. The effect of polyinosinic acid/polycytidilic acid on the immune response was also evaluated. The development of VZ specific cell-mediated response in normal subjects was characterized by intense proliferative activity eight to ten days after the onset of illness, with significant decline 70 to 80 days later. The responses in subjects with lymphoma or leukemia were much lower. Few subjects with chickenpox or zoster with lymphoma or leukemia died during the infection. Death was associated with significant depletion of E-rosette--forming T-cells, and grossly deficient specific cellular response to VZ antigen. Treatment with Poly IC frequently induced elevations in serum as well as vesicle fluid interferon levels, and increased the proliferative activity of lymphocytes against VZ antigen.
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Patel PA. Tuberculous appendicitis. Br J Clin Pract 1975; 29:87-90. [PMID: 1164459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Patel PA. Graduates of B.j. Medical college. Can Med Assoc J 1975; 112:148. [PMID: 20312620 PMCID: PMC1956428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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