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1.
J Proteome Res ; 23(1): 356-367, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38038604

RESUMO

Coronaviruses (CoV), including SARS-CoV-2, modulate host proteostasis through the activation of stress-responsive signaling pathways such as the Unfolded Protein Response (UPR), which remedies misfolded protein accumulation by attenuating translation and increasing protein folding capacity. While CoV nonstructural proteins (nsps) are essential for infection, little is known about the role of nsps in modulating the UPR. We characterized the impact of overexpression of SARS-CoV-2 nsp4, a key driver of replication, on the UPR in cell culture using quantitative proteomics to sensitively detect pathway-wide upregulation of effector proteins. We find that nsp4 preferentially activates the ATF6 and PERK branches of the UPR. Previously, we found that an N-terminal truncation of nsp3 (nsp3.1) can suppress pharmacological ATF6 activation. To determine how nsp3.1 and nsp4 tune the UPR, their coexpression demonstrated that nsp3.1 suppresses nsp4-mediated PERK, but not ATF6 activation. Reanalysis of SARS-CoV-2 infection proteomics data revealed time-dependent activation of PERK targets early in infection, which subsequently fades. This temporal regulation suggests a role for nsp3 and nsp4 in tuning the PERK pathway to attenuate host translation beneficial for viral replication while avoiding later apoptotic signaling caused by chronic activation. This work furthers our understanding of CoV-host proteostasis interactions and highlights the power of proteomic methods for systems-level analysis of the UPR.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Proteômica , Resposta a Proteínas não Dobradas , Técnicas de Cultura de Células
2.
bioRxiv ; 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37162862

RESUMO

Coronaviruses (CoV), including SARS-CoV-2, modulate host proteostasis through activation of stress-responsive signaling pathways such as the Unfolded Protein Response (UPR), which remedies misfolded protein accumulation by attenuating translation and increasing protein folding capacity. While CoV nonstructural proteins (nsps) are essential for infection, little is known about the role of nsps in modulating the UPR. We characterized the impact of SARS-CoV-2 nsp4, a key driver of replication, on the UPR using quantitative proteomics to sensitively detect pathway-wide upregulation of effector proteins. We find nsp4 preferentially activates the ATF6 and PERK branches of the UPR. Previously, we found an N-terminal truncation of nsp3 (nsp3.1) can suppress pharmacological ATF6 activation. To determine how nsp3.1 and nsp4 tune the UPR, their co-expression demonstrated that nsp3.1 suppresses nsp4-mediated PERK, but not ATF6 activation. Re-analysis of SARS-CoV-2 infection proteomics data revealed time-dependent activation of PERK targets early in infection, which subsequently fades. This temporal regulation suggests a role for nsp3 and nsp4 in tuning the PERK pathway to attenuate host translation beneficial for viral replication while avoiding later apoptotic signaling caused by chronic activation. This work furthers our understanding of CoV-host proteostasis interactions and highlights the power of proteomic methods for systems-level analysis of the UPR.

3.
J Perianesth Nurs ; 38(3): 488-492, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36599789

RESUMO

PURPOSE: Opioid free anesthesia (OFA) is associated with decreased risk of PONV and need for rescue analgesia, making it ideal for patients anticipating same-day discharge. The purpose of this project was to describe the perioperative care and short-term outcomes for patients undergoing robotic-assisted radical prostatectomy (RARP) under OFA at an ambulatory surgical center (ASC). DESIGN: A retrospective descriptive design was used to examine the perioperative care and short-term outcomes of patients undergoing RARP under OFA at an ASC. METHODS: The records of all sequential patients undergoing RARP over an 18-month period were reviewed. Data collected included patient comorbidities, surgical procedures, medications administered, verbal numeric rating scale (VNRS) for pain scores, times to oral intake, ambulation, and discharge, patient disposition, and unplanned return to the ER or hospital within 30 days. FINDINGS: Data were extracted from 54 sequential records. Median VNRS scores were zero throughout PACU stay. Fifty-three patients (98.1%) were successfully discharged home, with an average postoperative stay of 250.8 (SD 35.0) minutes. There were no complaints of post-discharge nausea and vomiting or intractable pain at 72 hours after surgery. One patient was transferred to the hospital and two patients returned to the emergency room within 30 days. CONCLUSIONS: Although generalizability is limited, these results suggest that carefully selected patients can be discharged home after RARP under a balanced OFA technique. Innovative practices are needed to address the current backlog of patients needing non-emergent surgery. Discharge home avoids the increase in resource consumption and infection risk associated with hospital admission.


Assuntos
Anestesia , Procedimentos Cirúrgicos Robóticos , Masculino , Humanos , Analgésicos Opioides/uso terapêutico , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/métodos , Procedimentos Cirúrgicos Ambulatórios/métodos , Assistência ao Convalescente , Alta do Paciente , Prostatectomia/efeitos adversos , Prostatectomia/métodos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia
4.
Cell Immunol ; 384: 104660, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36586393

RESUMO

Phosphatidylserine (PS) is an anionic phospholipid exposed on the surface of apoptotic cells. The exposure of PS typically recruits and signals phagocytes to engulf and silently clear these dying cells to maintain tolerance via immunological ignorance. However, recent and emerging evidence has demonstrated that PS converts an "immunogen" into a "tolerogen", and PS exposure on the surface of cells or vesicles actively promotes a tolerogenic environment. This tolerogenic property depends on the biophysical characteristics of PS-containing vesicles, including PS density on the particle surface to effectively engage tolerogenic receptors, such as TIM-4, which is exclusively expressed on the surface of antigen-presenting cells. We harnessed the cellular and molecular mechanistic insight of PS-mediated immune regulation to design an effective oral tolerance approach. This immunotherapy has been shown to prevent/reduce immune response against life-saving protein-based therapies, food allergens, autoantigens, and the antigenic viral capsid peptide commonly used in gene therapy, suggesting a broad spectrum of potential clinical applications. Given the good safety profile of PS together with the ease of administration, oral tolerance achieved with PS-based nanoparticles has a very promising therapeutic impact.


Assuntos
Imunoterapia , Fosfatidilserinas , Células Apresentadoras de Antígenos , Autoantígenos , Tolerância Imunológica , Apoptose
5.
HGG Adv ; 3(4): 100138, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36119806

RESUMO

Activity-dependent neuroprotective protein (ADNP) syndrome is a rare genetic condition associated with intellectual disability and autism spectrum disorder. Preclinical evidence suggests that low-dose ketamine may induce expression of ADNP and that neuroprotective effects of ketamine may be mediated by ADNP. The goal of the proposed research was to evaluate the safety, tolerability, and behavioral outcomes of low-dose ketamine in children with ADNP syndrome. We also sought to explore the feasibility of using electrophysiological markers of auditory steady-state response and computerized eye tracking to assess biomarker sensitivity to treatment. This study utilized a single-dose (0.5 mg/kg), open-label design, with ketamine infused intravenously over 40 min. Ten children with ADNP syndrome ages 6 to 12 years were enrolled. Ketamine was generally well tolerated, and there were no serious adverse events. The most common adverse events were elation/silliness (50%), fatigue (40%), and increased aggression (40%). Using parent-report instruments to assess treatment effects, ketamine was associated with nominally significant improvement in a wide array of domains, including social behavior, attention deficit and hyperactivity, restricted and repetitive behaviors, and sensory sensitivities, a week after administration. Results derived from clinician-rated assessments aligned with findings from the parent reports. Overall, nominal improvement was evident based on the Clinical Global Impressions - Improvement scale, in addition to clinician-based scales reflecting key domains of social communication, attention deficit and hyperactivity, restricted and repetitive behaviors, speech, thinking, and learning, activities of daily living, and sensory sensitivities. Results also highlight the potential utility of electrophysiological measurement of auditory steady-state response and eye-tracking to index change with ketamine treatment. Findings are intended to be hypothesis generating and provide preliminary support for the safety and efficacy of ketamine in ADNP syndrome in addition to identifying useful endpoints for a ketamine clinical development program. However, results must be interpreted with caution given limitations of this study, most importantly the small sample size and absence of a placebo-control group.

6.
Front Cell Dev Biol ; 10: 1094302, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36601536

RESUMO

Controversy surrounds the cellular role of the Bcl-2 family protein Bok. On one hand, it has been shown that all endogenous Bok is bound to inositol 1,4,5-trisphosphate receptors (IP3Rs), while other data suggest that Bok can act as a pro-apoptotic mitochondrial outer membrane permeabilization mediator, apparently kept at very low and non-apoptotic levels by efficient proteasome-mediated degradation. Here we show that 1) endogenous Bok is expressed at readily-detectable levels in key cultured cells (e.g., mouse embryonic fibroblasts and HCT116 cells) and is not constitutively degraded by the proteasome, 2) proteasome inhibitor-induced apoptosis is not mediated by Bok, 3) endogenous Bok expression level is critically dependent on the presence of IP3Rs, 4) endogenous Bok is rapidly degraded by the ubiquitin-proteasome pathway in the absence of IP3Rs at the endoplasmic reticulum membrane, and 5) charged residues in the transmembrane region of Bok affect its stability, ability to interact with Mcl-1, and pro-apoptotic activity when over-expressed. Overall, these data indicate that endogenous Bok levels are not governed by proteasomal activity (except when IP3Rs are deleted) and that while endogenous Bok plays little or no role in apoptotic signaling, exogenous Bok can mediate apoptosis in a manner dependent on its transmembrane domain.

7.
Sci Adv ; 6(36)2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32917607

RESUMO

Anomalously low winter sea ice extent and early retreat in CE 2018 and 2019 challenge previous notions that winter sea ice in the Bering Sea has been stable over the instrumental record, although long-term records remain limited. Here, we use a record of peat cellulose oxygen isotopes from St. Matthew Island along with isotope-enabled general circulation model (IsoGSM) simulations to generate a 5500-year record of Bering Sea winter sea ice extent. Results show that over the last 5500 years, sea ice in the Bering Sea decreased in response to increasing winter insolation and atmospheric CO2, suggesting that the North Pacific is highly sensitive to small changes in radiative forcing. We find that CE 2018 sea ice conditions were the lowest of the last 5500 years, and results suggest that sea ice loss may lag changes in CO2 concentrations by several decades.

8.
Med Sci Educ ; 30(4): 1367-1372, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34457802

RESUMO

An increasing number of medical schools are implementing curricular changes that better integrate clinical and basic sciences throughout all four years of medical school. One of the most frequently cited reasons is to improve medical student clinical reasoning skills while simultaneously aiming to decrease the attrition of basic science knowledge. Multiple pedagogical strategies have been explored to achieve this goal. We have found that simulation is a viable medium to integrate basic science within standardized patient encounters for early medical students.

9.
Neurology ; 93(21): e1932-e1943, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31653707

RESUMO

OBJECTIVE: To identify the rate of change of clinical outcome measures in children with 2 types of congenital muscular dystrophy (CMD), COL6-related dystrophies (COL6-RDs) and LAMA2-related dystrophies (LAMA2-RDs). METHODS: Over the course of 4 years, 47 individuals (23 with COL6-RD and 24 with LAMA2-RD) 4 to 22 years of age were evaluated. Assessments included the Motor Function Measure 32 (MFM32), myometry (knee flexors and extensors, elbow flexors and extensors), goniometry (knee and elbow extension), pulmonary function tests, and quality-of-life measures. Separate linear mixed-effects models were fitted for each outcome measurement, with subject-specific random intercepts. RESULTS: Total MFM32 scores for COL6-RDs and LAMA2-RDs decreased at a rate of 4.01 and 2.60 points, respectively, each year (p < 0.01). All muscle groups except elbow flexors for individuals with COL6-RDs decreased in strength between 1.70% (p < 0.05) and 2.55% (p < 0.01). Range-of-motion measurements decreased by 3.21° (p < 0.05) at the left elbow each year in individuals with LAMA2-RDs and 2.35° (p < 0.01) in right knee extension each year in individuals with COL6-RDs. Pulmonary function demonstrated a yearly decline in sitting forced vital capacity percent predicted of 3.03% (p < 0.01) in individuals with COL6-RDs. There was no significant change in quality-of-life measures analyzed. CONCLUSION: Results of this study describe the rate of change of motor function as measured by the MFM32, muscle strength, range of motion, and pulmonary function in individuals with COL6-RDs and LAMA2-RDs.


Assuntos
Distrofias Musculares/fisiopatologia , Esclerose/fisiopatologia , Adolescente , Artrometria Articular , Criança , Pré-Escolar , Progressão da Doença , Nutrição Enteral , Feminino , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Limitação da Mobilidade , Força Muscular , Dinamômetro de Força Muscular , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida , Testes de Função Respiratória , Capacidade Vital , Adulto Jovem
10.
Nat Commun ; 10(1): 3231, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324773

RESUMO

Sediment cores from Florida Bay, Everglades National Park were examined to determine ecosystem response to relative sea-level rise (RSLR) over the Holocene. High-resolution multiproxy analysis from four sites show freshwater wetlands transitioned to mangrove environments 4-3.6 ka, followed by estuarine environments 3.4-2.8 ka, during a period of enhanced climate variability. We calculate a RSLR rate of 0.67 ± 0.1 mm yr-1 between ~4.2-2.8 ka, 4-6 times lower than current rates. Despite low RSLR rates, the rapid mangrove to estuarine transgression was facilitated by a period of prolonged droughts and frequent storms. These findings suggest that with higher and accelerating RSLR today, enhanced climate variability could further hasten the loss of mangrove-lined coastlines, compounded by the reductions in natural flow to the coast caused by water management. Climate variability is nonlinear, and when superimposed on increases in RSLR, can complicate estimated trajectories of coastal inundation for resource management and urban planning.

11.
Muscle Nerve ; 57(1): 54-60, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28224647

RESUMO

INTRODUCTION: Electrical impedance myography (EIM) is a noninvasive electrophysiological technique that characterizes muscle properties through bioimpedance. We compared EIM measurements to function, strength, and disease severity in a population with congenital muscular dystrophy (CMD). METHODS: Forty-one patients with CMD, either collagen 6 related disorders (COL6-RD; n = 21) or laminin α-2-related disorders (LAMA2-RD; n = 20), and 21 healthy pediatric controls underwent 2 yearly EIM exams. In the CMD cohorts, EIM was compared with functional and strength measurements. RESULTS: Both CMD cohorts exhibited change over time and had correlation with disease severity. The 50-kHZ phase correlated well with function and strength in the COL6-RD cohort but not in the LAMA2-RD cohort. DISCUSSION: EIM is a potentially useful measure in clinical studies with CMD because of its sensitivity to change over a 1-year period and correlation with disease severity. For COL6-RD, there were also functional and strength correlations. Muscle Nerve 57: 54-60, 2018.


Assuntos
Colágeno Tipo VI/genética , Impedância Elétrica , Laminina/genética , Distrofias Musculares/congênito , Distrofias Musculares/genética , Miografia/métodos , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Força Muscular , Exame Neurológico/métodos , Corrida , Sensibilidade e Especificidade , Índice de Gravidade de Doença
12.
Neuromuscul Disord ; 27(3): 278-285, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28087121

RESUMO

Congenital muscular dystrophy (CMD) comprises a rare group of genetic muscle diseases that present at birth or early during infancy. Two common subtypes of CMD are collagen VI-related muscular dystrophy (COL6-RD) and laminin alpha 2-related dystrophy (LAMA2-RD). Traditional outcome measures in CMD include gross motor and mobility assessments, yet significant motor declines underscore the need for valid upper extremity motor assessments as a clinical endpoint. This study validated a battery of upper extremity measures in these two CMD subtypes for future clinical trials. For this cross-sectional study, 42 participants were assessed over the same 2-5 day period at the National Institutes of Health Clinical Center. All upper extremity measures were correlated with the Motor Function Measure 32 (MFM32). The battery of upper extremity assessments included the Jebsen Taylor Hand Function Test, Quality of Upper Extremity Skills Test (QUEST), hand held dynamometry, goniometry, and MyoSet Tools. Spearman Rho was used for correlations to the MFM32. Pearson was performed to correlate the Jebsen, QUEST, hand-held dynamometry, goniometry and the MyoSet Tools. Correlations were considered significant at the 0.01 level (2-tailed). Significant correlations were found between both the MFM32 and MFM Dimension 3 only (Distal Motor function) and the Jebsen, QUEST, MyoGrip and MyoPinch, elbow flexion/extension ROM and myometry. Additional correlations between the assessments are reported. The Jebsen, the Grasp and Dissociated Movements domains of the QUEST, the MyoGrip and the MyoPinch tools, as well as elbow ROM and myometry were determined to be valid and feasible in this population, provided variation in test items, and assessed a range of difficulty in CMD. To move forward, it will be of utmost importance to determine whether these upper extremity measures are reproducible and sensitive to change over time.


Assuntos
Colágeno Tipo VI , Laminina , Distrofias Musculares/diagnóstico , Índice de Gravidade de Doença , Extremidade Superior/fisiopatologia , Adolescente , Adulto , Criança , Pré-Escolar , Colágeno Tipo VI/deficiência , Estudos Transversais , Feminino , Humanos , Laminina/deficiência , Masculino , Distrofias Musculares/congênito , Adulto Jovem
13.
Bioorg Med Chem ; 18(4): 1396-405, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20133139

RESUMO

Using allylic azide rearrangement, a convenient method has been developed for the synthesis of 2',3'-dideoxyaminoglycosides that are, otherwise, difficult to be prepared. The antibacterial activity of these novel aminoglycosides also confirms the indispensable role of 2'-NH(2) group for both neomycin and kanamycin classes of aminoglycosides. A novel structural motif containing the hexylaminocarbonyl groups at O-5 and/or O-6 of 2',3'-dideoxyneamine could lead to the production of new aminoglycosides against resistant bacteria.


Assuntos
Aminoglicosídeos/síntese química , Azidas/química , Aminoglicosídeos/química , Aminoglicosídeos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Sequência de Carboidratos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Espectrometria de Massas por Ionização por Electrospray
14.
J Antibiot (Tokyo) ; 62(10): 539-44, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19629142

RESUMO

A library of 5''-modified neomycin derivatives were synthesized for an antibacterial structure-activity optimization strategy. Two leads exhibited prominent activity against both methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Antibacterial activities were measured when combined with other clinically used antibiotics. Significant synergistic activities were observed, which may lead to the development of novel therapeutic practices in the battle against infectious bacteria.


Assuntos
Antibacterianos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Neomicina , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Sinergismo Farmacológico , Quimioterapia Combinada , Enterococcus/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Conformação Molecular , Neomicina/análogos & derivados , Neomicina/síntese química , Neomicina/química , Neomicina/farmacologia , Relação Estrutura-Atividade , Resistência a Vancomicina
15.
Neuroimage ; 47(1): 342-52, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19376239

RESUMO

Despite ongoing debate about the nature of gender differences in mathematics achievement, little is known about gender similarities and differences in mathematical cognition at the neural level. We used fMRI to compare brain responses in 25 females and 24 males during a mental arithmetic task involving 3-operand addition and subtraction. We also used voxel-based morphometry (VBM) to examine gender differences in brain structure. Although females and males did not differ in accuracy or response times (effect size d<0.3), significant gender differences in functional brain activation were observed in the right dorsal and ventral visuospatial information processing streams (d>1.1). Males showed greater dorsal stream activation in the right intra-parietal sulcus areas important for numerical cognition, and angular gyrus regions of the default mode network that are typically deactivated during complex cognitive tasks, as well as greater ventral stream activation in the right lingual and parahippocampal gyri. VBM revealed an opposite pattern of gender differences-compared to males, females had greater regional density and greater regional volume in dorsal and ventral stream regions where males showed greater fMRI activation. There were no brain areas where females showed greater functional activation than males, and no brain areas where males showed greater structural density or volume than females. Our findings provide evidence for gender differences in the functional and structural organization of the right hemisphere brain areas involved in mathematical cognition. Together with the lack of behavioral differences, our results point to more efficient use of neural processing resources in females.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Cognição/fisiologia , Conceitos Matemáticos , Caracteres Sexuais , Adolescente , Adulto , Análise de Variância , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Tempo de Reação , Análise e Desempenho de Tarefas , Adulto Jovem
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