15 results on '"Minh-Vu H. Nguyen"'
Search Results
2. A Community-transmitted Case of Severe Acute Respiratory Distress Syndrome (SARS) Due to SARS-CoV-2 in the United States
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Angela Franciska Haczku, Kaitlyn A. Hardin, Stuart H. Cohen, Rebecca L. Corbett, Christian Sebat, Michael Schivo, Wesley Pidcock, Bradley C. Sanville, George Richard Thompson, and Minh Vu H. Nguyen
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ARDS ,Disease ,030204 cardiovascular system & hematology ,medicine.disease_cause ,Medical and Health Sciences ,0302 clinical medicine ,Risk Factors ,030212 general & internal medicine ,Tomography ,Lung ,Index case ,Coronavirus ,Respiratory Distress Syndrome ,screening and diagnosis ,Alanine ,Transmission (medicine) ,Brief Report ,Shock ,Thorax ,Middle Aged ,Health Services ,Biological Sciences ,Shock, Septic ,community transmission ,X-Ray Computed ,Community-Acquired Infections ,Detection ,AcademicSubjects/MED00290 ,Treatment Outcome ,Infectious Diseases ,Pneumonia & Influenza ,Female ,Adult ,Microbiology (medical) ,medicine.medical_specialty ,index case ,novel coronavirus ,MEDLINE ,Antiviral Agents ,Microbiology ,03 medical and health sciences ,Rare Diseases ,Clinical Research ,medicine ,Humans ,Intensive care medicine ,Septic ,SARS-CoV-2 ,business.industry ,Prevention ,Public health ,COVID-19 ,Pneumonia ,medicine.disease ,Adenosine Monophosphate ,United States ,COVID-19 Drug Treatment ,4.1 Discovery and preclinical testing of markers and technologies ,Emerging Infectious Diseases ,Good Health and Well Being ,Tomography, X-Ray Computed ,business - Abstract
This is the first known community transmission case of the novel coronavirus disease (COVID-19) in the United States, with significant public health implications. Diagnosis of COVID-19 is currently confirmed with PCR based testing of appropriate respiratory samples. Given the absence of travel or known exposure history, this patient did not meet the criteria for testing according to CDC guidelines at the time of her presentation. Since this case, any patient with severe disease (eg, ARDS or pneumonia) requiring hospitalization without an explanatory diagnosis can be tested even if no clear source of exposure is identified. While influencing national health policies for revising screening criteria, this case also highlighted significant knowledge gaps in diagnosis and treatment and a desperate need for early, widespread, fast and cheap testing for COVID-19.
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- 2020
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3. Clinical and Radiographic Manifestations of Sputum Culture-Negative Pulmonary Tuberculosis.
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Minh-Vu H Nguyen, Elizabeth R Jenny-Avital, Susanne Burger, Eric M Leibert, and Jacqueline M Achkar
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Medicine ,Science - Abstract
Intervention at the earliest possible stage of pulmonary tuberculosis (PTB) reduces morbidity for the individual and transmission for the community. We characterize the clinical and radiographic manifestations of sputum culture-negative (Cx-) PTB in order to facilitate awareness of this under recognized and likely early disease state. In this cross-sectional sub-study, we reviewed the medical records of HIV-uninfected PTB patients enrolled from 2006-2014 within the context of a TB biomarker study in New York City. Cx- PTB was defined as clinical and/or radiographic presentation consistent with PTB, three initial mycobacterial sputum cultures negative, and no evidence of other respiratory disease. Diagnosis was confirmed by clinical and radiographic improvement on antituberculous treatment and/or culture, nucleic acid, or histological confirmation from a specimen other than the initial three sputa. Cx+ PTB was defined as above but with M. tuberculosis growth in at least one of the first three sputum cultures. Demographics, symptoms, and radiographic findings on initial presentation were compared between the two groups. Of 99 subjects diagnosed with PTB, 21 met the criteria of Cx- PTB. Cx- compared to Cx+ subjects presented with a significantly lower frequency of cough (70% vs. 91%, P = 0.02), sputum production (30% vs. 64%, P < 0.01), weight loss (25% vs. 54%, P = 0.02), and frequency of cavitation on chest CT (12% vs. 68%, P < 0.01). Our findings should raise awareness that neither a positive culture nor the hallmark symptoms are invariably associated with early TB disease.
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- 2015
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4. Posaconazole Serum Drug Levels Associated With Pseudohyperaldosteronism
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Matthew R Davis, Alex Odermatt, George Richard Thompson, John W. Baddley, Brian Y Young, Minh Vu H. Nguyen, Ian Howard Mchardy, and Rebecca Wittenberg
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0301 basic medicine ,Microbiology (medical) ,Aging ,medicine.medical_specialty ,Posaconazole ,Antifungal Agents ,hypertension ,therapeutic drug monitoring ,030106 microbiology ,Secondary hypertension ,Cardiovascular ,Pseudohyperaldosteronism ,Aspergillosis ,Medical and Health Sciences ,Microbiology ,Gastroenterology ,03 medical and health sciences ,Clinical Research ,Internal medicine ,hypokalemia ,medicine ,Humans ,Articles and Commentaries ,Retrospective Studies ,Aged ,medicine.diagnostic_test ,business.industry ,Mucormycosis ,toxicity ,Evaluation of treatments and therapeutic interventions ,Triazoles ,Biological Sciences ,medicine.disease ,Hypokalemia ,triazole ,030104 developmental biology ,Infectious Diseases ,Blood pressure ,Therapeutic drug monitoring ,6.1 Pharmaceuticals ,medicine.symptom ,business ,Invasive Fungal Infections ,medicine.drug - Abstract
BackgroundPosaconazole tablets are well tolerated and efficacious in the prophylaxis and treatment of aspergillosis, mucormycosis, and other invasive fungal infections. There have been case reports of posaconazole-induced pseudohyperaldosteronism (PIPH); however, its occurrence and association with serum posaconazole drug levels have not previously been investigated.MethodsIn this single-center, retrospective, observational study, we examined the occurrence of PIPH in outpatients newly starting posaconazole and evaluated differences in serum posaconazole concentrations and clinical characteristics between those with and without this syndrome.ResultsSixty-nine patients receiving posaconazole were included, of whom 16 (23.2%) met the definition of PIPH. Patients with PIPH were significantly older (61.1 vs 44.7 years, P = .007) and more frequently had hypertension prior to starting posaconazole (68.8% vs 32.1%, P = .009). Patients with PIPH had a significantly higher median serum posaconazole level than those without PIPH (3.0 vs 1.2 µg/mL, P ≤ .0001). There was a positive correlation between serum posaconazole levels and changes in systolic blood pressure (r = .37, P = .01), a negative correlation between serum posaconazole levels and changes in serum potassium (r = –.39, P = .006), and a positive correlation between serum posaconazole levels and serum 11-deoxycortisol (r = .69, P < .0001).ConclusionsPosaconazole is associated with secondary hypertension and hypokalemia, consistent with pseudohyperaldosteronism, and development is associated with higher serum posaconazole concentrations, older age, and baseline hypertension.
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- 2019
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5. Spiromastigoides asexualis: Phylogenetic Analysis and Evaluation as a Cause of False-Positive Blastomyces DNA Probe Test Results
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Minh Vu H. Nguyen, Carmita Sanders, George Richard Thompson, Nathan P. Wiederhold, Connie Cañete-Gibas, and Diekema, Daniel J
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0301 basic medicine ,Microbiology (medical) ,Antifungal Agents ,030106 microbiology ,Mycology ,Fungus ,Spiromastigoides ,Medical and Health Sciences ,Microbiology ,Blastomycosis ,blastomycosis ,03 medical and health sciences ,Phylogenetics ,mental disorders ,medicine ,Genetics ,Humans ,Phylogeny ,Blastomyces ,biology ,Phylogenetic tree ,novel ,Agricultural and Veterinary Sciences ,Hybridization probe ,fungus ,mold ,nutritional and metabolic diseases ,Biological Sciences ,medicine.disease ,biology.organism_classification ,Laboratory results ,phylogenetics ,030104 developmental biology ,DNA probe ,Infectious Diseases ,fungal ,phylogenetic ,false-positive ,DNA Probes ,Infection ,Phylogenetic relationship - Abstract
This is the first case of Spiromastigoides asexualis human infection, and it notably gave a false-positive Blastomyces DNA probe laboratory result. We further investigated other Spiromastigoides isolates as a cause of false-positive testing results, their phylogenetic relationship, and their susceptibility profiles to clinically available antifungal agents. Other S. asexualis isolates also resulted in positive Blastomyces DNA probe results, while Spiromastigoides species other than S. asexualis did not.
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- 2020
6. Investigation of nosocomial SARS-CoV-2 transmission from two patients to healthcare workers identifies close contact but not airborne transmission events
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Janelle Vu Pugashetti, Chinh Phan, Hien H. Nguyen, Sarah Waldman, Joel Tourtellotte, Stuart H. Cohen, Carla S. Martin, Minh Vu H. Nguyen, George Richard Thompson, Gregory Y. Warner, Bennett H. Penn, Christian Sandrock, and Derek J. Bays
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Microbiology (medical) ,medicine.medical_specialty ,Infectious Disease Transmission, Patient-to-Professional ,Epidemiology ,Health Personnel ,Infectious Disease Transmission ,Secondary infection ,Context (language use) ,030501 epidemiology ,Medical and Health Sciences ,Airborne transmission ,Patient-to-Professional ,Vaccine Related ,03 medical and health sciences ,Clinical Research ,Biodefense ,Pandemic ,Humans ,Medicine ,Pandemics ,Lung ,Personal protective equipment ,Cross Infection ,SARS-CoV-2 ,business.industry ,Transmission (medicine) ,Prevention ,COVID-19 ,Community hospital ,Transmission-based precautions ,Emerging Infectious Diseases ,Good Health and Well Being ,Infectious Diseases ,Emergency medicine ,Original Article ,Infection ,0305 other medical science ,business - Abstract
Objective:To describe the pattern of transmission of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) during 2 nosocomial outbreaks of coronavirus disease 2019 (COVID-19) with regard to the possibility of airborne transmission.Design:Contact investigations with active case finding were used to assess the pattern of spread from 2 COVID-19 index patients.Setting:A community hospital and university medical center in the United States, in February and March, 2020, early in the COVID-19 pandemic.Patients:Two index patients and 421 exposed healthcare workers.Methods:Exposed healthcare workers (HCWs) were identified by analyzing the electronic medical record (EMR) and conducting active case finding in combination with structured interviews. Healthcare coworkers (HCWs) were tested for COVID-19 by obtaining oropharyngeal/nasopharyngeal specimens, and RT-PCR testing was used to detect SARS-CoV-2.Results:Two separate index patients were admitted in February and March 2020, without initial suspicion for COVID-19 and without contact or droplet precautions in place; both patients underwent several aerosol-generating procedures in this context. In total, 421 HCWs were exposed in total, and the results of the case contact investigations identified 8 secondary infections in HCWs. In all 8 cases, the HCWs had close contact with the index patients without sufficient personal protective equipment. Importantly, despite multiple aerosol-generating procedures, there was no evidence of airborne transmission.Conclusion:These observations suggest that, at least in a healthcare setting, most SARS-CoV-2 transmission is likely to take place during close contact with infected patients through respiratory droplets, rather than by long-distance airborne transmission.
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- 2020
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7. Tolerability of long-term fluconazole therapy
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Matthew R Davis, George Richard Thompson, Minh Vu H. Nguyen, and Monica A. Donnelley
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Adult ,Male ,0301 basic medicine ,Microbiology (medical) ,medicine.medical_specialty ,Antifungal Agents ,Time Factors ,Drug-Related Side Effects and Adverse Reactions ,030106 microbiology ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Humans ,Medicine ,Pharmacology (medical) ,030212 general & internal medicine ,Adverse effect ,Fluconazole ,Toxicity profile ,Retrospective Studies ,Pharmacology ,Coccidioidomycosis ,business.industry ,Retrospective cohort study ,Discontinuation ,Clinical trial ,Treatment Outcome ,Infectious Diseases ,Tolerability ,Female ,Dose reduction ,business ,medicine.drug - Abstract
BACKGROUND Fluconazole is a commonly prescribed first-generation triazole antifungal. Although the toxicity profile of fluconazole has been evaluated in clinical trials, there are scant data regarding its tolerability with long-term therapy. Treatment guidelines for coccidioidomycosis recommend fluconazole therapy and severe or disseminated infections can require lifelong treatment. OBJECTIVES To assess the prevalence of long-term fluconazole adverse effects, their consequences for antifungal therapy, time to adverse effects and the association between dosing regimen or fluconazole serum level and adverse effect status. METHODS We conducted a single-centre, retrospective study of adult patients (≥18 years) with proven or probable coccidioidomycosis receiving long-term fluconazole therapy for an intended duration of ≥28 days. RESULTS Out of 124 patients included, 64 (51.6%) experienced adverse effects. The most common adverse effects were xerosis (16.9%), alopecia (16.1%) and fatigue (11.3%). Of the 64 patients experiencing adverse effects, 42 (65.6%) required a therapeutic intervention such as dose reduction, discontinuation or switch to a new antifungal. Patients experiencing adverse effects were prescribed higher total daily fluconazole doses (6.7 versus 5.7 mg/kg; P
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- 2018
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8. Quantum chemical studies of redox properties and conformational changes of a four-center iron CO2 reduction electrocatalyst
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Hyesu Jang, Marshall E Hutchings, Yudong Qiu, Louise A. Berben, Lee-Ping Wang, and Minh Vu H. Nguyen
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010304 chemical physics ,Chemistry ,Side reaction ,General Chemistry ,Activation energy ,010402 general chemistry ,Electrocatalyst ,01 natural sciences ,Redox ,Dissociation (chemistry) ,0104 chemical sciences ,Molecular dynamics ,Catalytic cycle ,Ab initio quantum chemistry methods ,0103 physical sciences ,Physical chemistry - Abstract
The CO2 reduction electrocatalyst [Fe4N(CO)12]- (abbrev. 1-) reduces CO2 to HCO2- in a two-electron, one-proton catalytic cycle. Here, we employ ab initio calculations to estimate the first two redox potentials of 1- and explore the pathway of a side reaction involving CO dissociation from 13-. Using the BP86 density functional approximation, the redox potentials were computed with a root mean squared error of 0.15 V with respect to experimental data. High temperature Born-Oppenheimer molecular dynamics was employed to discover a reaction pathway of CO dissociation from 13- with a reaction energy of +10.6 kcal mol-1 and an activation energy of 18.8 kcal mol-1; including harmonic free energy terms, this yields ΔGsep = 1.4 kcal mol-1 for fully separated species and ΔG‡ = +17.4 kcal mol-1, indicating CO dissociation is energetically accessible at ambient conditions. The analogous dissociation pathway from 12- has a reaction energy of 22.1 kcal mol-1 and an activation energy of 22.4 kcal mol-1 (ΔGsep = 12.8 kcal mol-1, ΔG‡ = +18.1 kcal mol-1). Our computed harmonic vibrational analysis of [Fe4N(CO)11]3- or 23- reveals a distinct CO-stretching peak red-shifted from the main CO-stretching band, pointing to a possible vibrational signature of dissociation. Multi-reference CASSCF calculations are used to check the assumptions of the density functional approximations that were used to obtain the majority of the results.
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- 2018
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9. The double-edged sword - prosthetic joint infection following BCG treatment for bladder cancer: a case report
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Mauro Giordani, George Richard Thompson, and Minh Vu H. Nguyen
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0301 basic medicine ,Male ,Prosthetic joint infection ,Case Report ,0302 clinical medicine ,Medical microbiology ,80 and over ,2.1 Biological and endogenous factors ,BCG ,030212 general & internal medicine ,Aetiology ,Initial therapy ,Cancer ,Aged, 80 and over ,Mycobacterium bovis ,biology ,Infectious ,Anti-Bacterial Agents ,Infectious Diseases ,Medical Microbiology ,BCG Vaccine ,Infection ,Urologic Diseases ,medicine.medical_specialty ,Prosthetic joint ,030106 microbiology ,Clinical Sciences ,and over ,Microbiology ,Attenuated strain ,lcsh:Infectious and parasitic diseases ,Vaccine Related ,03 medical and health sciences ,Clinical Research ,medicine ,Humans ,lcsh:RC109-216 ,Intensive care medicine ,Aged ,Arthritis, Infectious ,Bladder cancer ,Hip ,business.industry ,Arthritis ,biology.organism_classification ,medicine.disease ,Good Health and Well Being ,Urinary Bladder Neoplasms ,Complication ,business - Abstract
Background Prosthetic joint infections remain a significant cause of morbidity and are frustrating for patients and physicians alike. Unusual causes of infection may be seen in selected circumstances and a high index of suspicion and a careful history are required to ensure an accurate and timely diagnosis can be made. Case presentation We present a case of Mycobacterium bovis prosthetic joint infection secondary to intravesicular Bacillus Calmette-Guérin (BCG) treatment for prior bladder cancer definitively identified by spoligotyping. A favorable clinical outcome was observed following surgical intervention and a 12-month course of anti-mycobacterial therapy. Conclusions BCG therapy, a live attenuated strain of M. bovis, has become the mainstay of adjunctive therapy for bladder cancer and infectious complications, including those affecting the musculoskeletal system, may be seen years after initial therapy. An awareness of this complication and appropriate discussions with the institution’s microbiology laboratory may allow for an accurate and timely identification.
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- 2019
10. Factors Associated With Sputum Culture-Negative vs Culture-Positive Diagnosis of Pulmonary Tuberculosis
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Jacqueline M. Achkar, Douglas Proops, Shama D. Ahuja, Minh Vu H. Nguyen, Lisa Trieu, and Natalie S. Levy
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Adult ,Male ,medicine.medical_specialty ,Tuberculosis ,Cross-sectional study ,Disease ,Sputum culture ,Mycobacterium tuberculosis ,03 medical and health sciences ,0302 clinical medicine ,Interquartile range ,Internal medicine ,medicine ,Humans ,030212 general & internal medicine ,Tuberculosis, Pulmonary ,Original Investigation ,integumentary system ,biology ,medicine.diagnostic_test ,business.industry ,Research ,Sputum ,General Medicine ,Middle Aged ,biology.organism_classification ,medicine.disease ,Comorbidity ,3. Good health ,Online Only ,Infectious Diseases ,Cross-Sectional Studies ,030228 respiratory system ,Cough ,Female ,New York City ,Radiography, Thoracic ,medicine.symptom ,business - Abstract
Key Points Question What proportion of patients with pulmonary tuberculosis have negative sputum culture results, and how do they present differently from patients with culture-positive pulmonary tuberculosis? Findings In our cross-sectional study of 796 patients without HIV infection who were diagnosed with pulmonary tuberculosis, sputum culture-negative pulmonary tuberculosis represented 15% of all adult patients with pulmonary tuberculosis in New York, New York. These patients had a significantly lower proportion of cough, weight loss, any symptom in general, and cavitation on imaging compared with patients with sputum culture-positive disease. Meaning Through awareness of these findings, the detection and treatment of this likely early disease could potentially be improved and the development of transmissible tuberculosis reduced., Importance Recognition of active tuberculosis (TB) in its earliest stages could reduce morbidity and prevent advancement to transmissible disease. Little is published about the occurrence and presentation of sputum culture-negative pulmonary TB (PTB), an early paucibacillary but often underrecognized disease state. Objective To assess differences between culture-negative and culture-positive PTB regarding occurrence, clinical presentation, radiographic findings, demographics, and comorbidities. Design, Setting, and Participants Cross-sectional study in which surveillance data of adult patients with PTB reported to the New York City Department of Health in New York, New York, from 2011 through 2013, ie, years for which demographic, clinical, and radiographic data were collected. Patients were aged 18 years or older, had signs of pulmonary disease, and had mycobacterial sputum culture results; those with HIV coinfection or a TB diagnosis within 2 years prior to presentation were excluded. Culture-negative PTB was defined as clinical and radiographic presentation consistent with TB, 3 negative results on sputum culture, and improvement with antituberculous treatment. The analyses were performed between 2015 and 2016; notably, the proportion of reported patients with culture-negative PTB has remained consistent during the past 2 decades. Main Outcomes and Measures The occurrence of culture-negative PTB among all patients with PTB was calculated, and demographics, comorbidities, symptoms, and radiographic findings were compared between culture-negative and culture-positive PTB. Results Of the 796 patients with PTB (median [interquartile range] age, 41 [29-54] years; 499 [63%] men) who met criteria for analysis, 116 (15%) had negative results on sputum culture. Patients with culture-negative PTB compared with culture-positive PTB were less frequently male (53% vs 64%; P = .03) and presented with a significantly lower frequency of cough (68% vs 89%; P, This cross-sectional study compares the occurrence, clinical presentation, radiographic findings, demographics, and comorbidities in adult patients with culture-negative vs culture-positive pulmonary tuberculosis.
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- 2019
11. Reply to DiPippo and Kontoyiannis
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George Richard Thompson, Alex Odermatt, and Minh Vu H. Nguyen
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Microbiology (medical) ,Infectious Diseases ,Information retrieval ,Text mining ,Pharmaceutical Preparations ,business.industry ,MEDLINE ,Humans ,Medicine ,Triazoles ,business - Published
- 2019
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12. Adenylyl Cyclase Anchoring by a Kinase Anchor Protein AKAP5 (AKAP79/150) Is Important for Postsynaptic β-Adrenergic Signaling
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Hai Qian, Tommaso Patriarchi, Ivar S. Stein, Yang Kevin Xiang, Lucas Matt, Mingxu Zhang, Johannes W. Hell, and Minh Vu H. Nguyen
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medicine.medical_specialty ,Adrenergic beta-Antagonists ,Long-Term Potentiation ,A Kinase Anchor Proteins ,Neurotransmission ,Biology ,Hippocampus ,Synaptic Transmission ,Biochemistry ,Adenylyl cyclase ,Mice ,chemistry.chemical_compound ,Prosencephalon ,Neurobiology ,Postsynaptic potential ,Internal medicine ,medicine ,Animals ,Receptors, AMPA ,Phosphorylation ,Molecular Biology ,Mice, Knockout ,Isoproterenol ,Post-Synaptic Density ,Long-term potentiation ,Cell Biology ,Adrenergic beta-Agonists ,Cyclic AMP-Dependent Protein Kinases ,Propranolol ,Cell biology ,Mice, Inbred C57BL ,Protein Subunits ,Protein Transport ,Endocrinology ,chemistry ,Synaptic plasticity ,Receptors, Adrenergic, beta-2 ,Protein Processing, Post-Translational ,Postsynaptic density ,Adenylyl Cyclases - Abstract
Recent evidence indicates that the A kinase anchor protein AKAP5 (AKAP79/150) interacts not only with PKA but also with various adenylyl cyclase (AC) isoforms. However, the physiological relevance of AC-AKAP5 binding is largely unexplored. We now show that postsynaptic targeting of AC by AKAP5 is important for phosphorylation of the AMPA-type glutamate receptor subunit GluA1 on Ser-845 by PKA and for synaptic plasticity. Phosphorylation of GluA1 on Ser-845 is strongly reduced (by 70%) under basal conditions in AKAP5 KO mice but not at all in D36 mice, in which the PKA binding site of AKAP5 (i.e. the C-terminal 36 residues) has been deleted without affecting AC association with GluA1. The increase in Ser-845 phosphorylation upon β-adrenergic stimulation is much more severely impaired in AKAP5 KO than in D36 mice. In parallel, long term potentiation induced by a 5-Hz/180-s tetanus, which mimics the endogenous θ-rhythm and depends on β-adrenergic stimulation, is only modestly affected in acute forebrain slices from D36 mice but completely abrogated in AKAP5 KO mice. Accordingly, anchoring of not only PKA but also AC by AKAP5 is important for regulation of postsynaptic functions and specifically AMPA receptor activity.
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- 2013
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13. β2-Adrenergic receptor supports prolonged theta tetanus-induced LTP
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Hai Qian, Tommaso Patriarchi, Kaiwen He, Olha M. Koval, Mark E. Anderson, Hey Kyoung Lee, Mingxu Zhang, Minh Vu H. Nguyen, Johannes W. Hell, and Lucas Matt
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Physiology ,Adrenergic beta-Antagonists ,Long-Term Potentiation ,Adrenergic ,Neurotransmission ,Synaptic Transmission ,Arousal ,Propanolamines ,Mice ,Dobutamine ,Receptors, Adrenergic, beta ,Animals ,Medicine ,Phosphorylation ,Protein kinase A ,Receptor ,CA1 Region, Hippocampal ,Mice, Knockout ,business.industry ,musculoskeletal, neural, and ocular physiology ,General Neuroscience ,Imidazoles ,Long-term potentiation ,Articles ,Electric Stimulation ,nervous system ,Adrenergic beta-1 Receptor Agonists ,Synapses ,Rabbits ,business ,Neuroscience - Abstract
The widespread noradrenergic innervation in the brain promotes arousal and learning by molecular mechanisms that remain largely undefined. Recent work shows that the β2-adrenergic receptor (β2AR) is linked to the AMPA-type glutamate receptor subunit GluA1 via stargazin and PSD-95 (Joiner ML, Lise MF, Yuen EY, Kam AY, Zhang M, Hall DD, Malik ZA, Qian H, Chen Y, Ulrich JD, Burette AC, Weinberg RJ, Law PY, El-Husseini A, Yan Z, Hell JW. EMBO J 29: 482–495, 2010). We now demonstrate that the β2AR plays a prominent role in long-term potentiation (LTP) induced by a train of 900 stimuli at 5 Hz (prolonged theta-tetanus-LTP, or PTT-LTP) in the hippocampal CA1 region in mice, which requires simultaneous β-adrenergic stimulation. Although PTT-LTP was impaired in hippocampal slices from β1AR and β2AR knockout (KO) mice, only β2AR-selective stimulation with salbutamol supported this PTT-LTP in wild-type (WT) slices, whereas β1AR-selective stimulation with dobutamine (+ prazosin) did not. Furthermore, only the β2AR-selective antagonist ICI-118551 and not the β1AR-selective antagonist CGP-20712 inhibited PTT-LTP and phosphorylation of GluA1 on its PKA site S845 in WT slices. Our analysis of S845A knockin (KI) mice indicates that this phosphorylation is relevant for PTT-LTP. These results identify the β2AR-S845 signaling pathway as a prominent regulator of synaptic plasticity.
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- 2012
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14. Clinical and Radiographic Manifestations of Sputum Culture-Negative Pulmonary Tuberculosis
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Eric Leibert, Susanne Burger, Minh Vu H. Nguyen, Elizabeth R. Jenny-Avital, and Jacqueline M. Achkar
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Adult ,Male ,medicine.medical_specialty ,Pathology ,Tuberculosis ,lcsh:Medicine ,Context (language use) ,Disease ,Sputum culture ,Mycobacterium tuberculosis ,Internal medicine ,medicine ,Humans ,lcsh:Science ,Tuberculosis, Pulmonary ,Multidisciplinary ,medicine.diagnostic_test ,biology ,integumentary system ,business.industry ,Respiratory disease ,lcsh:R ,Sputum ,Middle Aged ,medicine.disease ,biology.organism_classification ,3. Good health ,Radiography ,Cross-Sectional Studies ,Biomarker (medicine) ,Female ,lcsh:Q ,medicine.symptom ,business ,Research Article - Abstract
Intervention at the earliest possible stage of pulmonary tuberculosis (PTB) reduces morbidity for the individual and transmission for the community. We characterize the clinical and radiographic manifestations of sputum culture-negative (Cx-) PTB in order to facilitate awareness of this under recognized and likely early disease state. In this cross-sectional sub-study, we reviewed the medical records of HIV-uninfected PTB patients enrolled from 2006-2014 within the context of a TB biomarker study in New York City. Cx- PTB was defined as clinical and/or radiographic presentation consistent with PTB, three initial mycobacterial sputum cultures negative, and no evidence of other respiratory disease. Diagnosis was confirmed by clinical and radiographic improvement on antituberculous treatment and/or culture, nucleic acid, or histological confirmation from a specimen other than the initial three sputa. Cx+ PTB was defined as above but with M. tuberculosis growth in at least one of the first three sputum cultures. Demographics, symptoms, and radiographic findings on initial presentation were compared between the two groups. Of 99 subjects diagnosed with PTB, 21 met the criteria of Cx- PTB. Cx- compared to Cx+ subjects presented with a significantly lower frequency of cough (70% vs. 91%, P = 0.02), sputum production (30% vs. 64%, P < 0.01), weight loss (25% vs. 54%, P = 0.02), and frequency of cavitation on chest CT (12% vs. 68%, P < 0.01). Our findings should raise awareness that neither a positive culture nor the hallmark symptoms are invariably associated with early TB disease.
- Published
- 2015
15. Competition between α-actinin and Ca2+-Calmodulin Controls Surface Retention of the L-type Ca2+ Channel CaV1.2
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Lucas Matt, Ricardo E. Dolmetsch, Shuiping Dai, Pang-Yen Tseng, Johannes W. Hell, Durga P. Mohapatra, Richard J. Weinberg, Minh Vu H. Nguyen, Andrew Shephard, Carl J. Christel, Katrin Schnizler, Duane D. Hall, Amy S. Lee, Fuminori Tsuruta, Alain C. Burette, and Zulfiqar A. Malik
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Dendritic spine ,Calmodulin ,Calcium Channels, L-Type ,Neuroscience(all) ,Protein subunit ,media_common.quotation_subject ,Dendritic Spines ,Endocytosis ,Receptors, N-Methyl-D-Aspartate ,Cav1.2 ,Article ,Small hairpin RNA ,03 medical and health sciences ,0302 clinical medicine ,Humans ,Actinin ,Internalization ,030304 developmental biology ,media_common ,Neurons ,0303 health sciences ,Binding Sites ,biology ,Voltage-dependent calcium channel ,General Neuroscience ,Brain ,Cell biology ,HEK293 Cells ,biology.protein ,030217 neurology & neurosurgery - Abstract
Regulation of neuronal excitability and cardiac excitation-contraction coupling requires the proper localization of L-type Ca²⁺ channels. We show that the actin-binding protein α-actinin binds to the C-terminal surface targeting motif of α11.2, the central pore-forming Ca(V)1.2 subunit, in order to foster its surface expression. Disruption of α-actinin function by dominant-negative or small hairpin RNA constructs reduces Ca(V)1.2 surface localization in human embryonic kidney 293 and neuronal cultures and dendritic spine localization in neurons. We demonstrate that calmodulin displaces α-actinin from their shared binding site on α11.2 upon Ca²⁺ influx through L-type channels, but not through NMDAR, thereby triggering loss of Ca(V)1.2 from spines. Coexpression of a Ca²⁺-binding-deficient calmodulin mutant does not affect basal Ca(V)1.2 surface expression but inhibits its internalization upon Ca²⁺ influx. We conclude that α-actinin stabilizes Ca(V)1.2 at the plasma membrane and that its displacement by Ca²⁺-calmodulin triggers Ca²⁺-induced endocytosis of Ca(V)1.2, thus providing an important negative feedback mechanism for Ca²⁺ influx.
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- 2013
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