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1.
J Plast Reconstr Aesthet Surg ; 82: 176-185, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37186973

RESUMO

BACKGROUND: Common mental disorders (CMD) are highly morbid conditions not routinely screened for in chronic wound care. A comorbid psychiatric condition's influence on a patient with chronic wounds' quality of life (QoL) is unknown. This study investigates the implications of CMD on QoL in patients with chronic lower extremity (LE) wounds. METHODS: This cross-sectional study surveyed patients with chronic LE wounds evaluated in our multidisciplinary clinic between June-July 2022. Surveys included validated physical and social QoL questionnaires, including the Lower Extremity Functional Scale (LEFS), Patient-Reported Outcomes Measurement Information System (PROMIS-3a) Scale v2.0, 12-Item Short-Form (SF-12), and a screening tool for common mental disorders, the Self-Reporting Questionnaire 20 (SRQ-20). Data regarding patient demographics, comorbidities, psychiatric diagnoses, and wound care history were retrospectively collected. RESULTS: Of the 265 identified patients, 39 (14.7%) had documented psychiatric diagnoses, most often depression or anxiety. The diagnosed cohort had higher median SRQ-20 scores (6, IQR: 6 vs. 3, IQR: 5; P < 0.001) and a higher proportion of positive screens for CMD (30.8% vs. 15.5%; P = 0.020) than non-diagnosed patients. There were no differences in physical or social QoL in patients with and without a psychiatric diagnosis. However, individuals screening positively for CMD experienced significantly more pain (T-score 60.2 vs. 51.4, P = 0.0052) and reduced function (LEFS 26.0 vs. 41.0, P < 0.0000). CONCLUSION: This study illustrates that patients with chronic LE wounds experience potentially meaningful psychologic distress. Further, symptoms of a CMD (SRQ-20 ≥8), rather than a previous diagnosis, may influence pain and functional outcomes. These findings emphasize the potential relevance of psychological distress in this population and reinforce the need for further investigation of actionable responses to this apparent need.


Assuntos
Transtornos Mentais , Qualidade de Vida , Humanos , Estudos Transversais , Estudos Retrospectivos , Transtornos Mentais/complicações , Transtornos Mentais/epidemiologia , Inquéritos e Questionários , Dor
2.
Dis Mon ; 68(12): 101465, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36008166

RESUMO

Pulmonary renal syndrome (PRS) is a constellation of different disorders that cause both rapidly progressive glomerulonephritis and diffuse alveolar hemorrhage. While antineutrophil cytoplasmic antibody associated vasculitis and anti-glomerular basement membrane disease are the predominant causes of PRS, numerous other mechanisms have been shown to cause this syndrome, including thrombotic microangiopathies, drug exposures, and infections, among others. This syndrome has high morbidity and mortality, and early diagnosis and treatment is imperative to improve outcomes. Treatment generally involves glucocorticoids and immunosuppressive agents, but treatment targeted to the underlying disorder can improve outcomes and mitigate side effects. Familiarity with the wide range of possible causes of PRS can aid the clinician in workup, diagnosis and early initiation of treatment. This review provides a summary of the clinical presentation, etiologies, pathophysiology, and treatment of PRS.


Assuntos
Doença Antimembrana Basal Glomerular , Glomerulonefrite , Pneumopatias , Humanos , Doença Antimembrana Basal Glomerular/complicações , Doença Antimembrana Basal Glomerular/diagnóstico , Anticorpos Anticitoplasma de Neutrófilos/uso terapêutico , Glomerulonefrite/diagnóstico , Glomerulonefrite/etiologia , Glomerulonefrite/terapia , Pneumopatias/diagnóstico , Pneumopatias/etiologia , Pneumopatias/terapia , Hemorragia/etiologia , Hemorragia/terapia , Hemorragia/diagnóstico , Imunossupressores/uso terapêutico
3.
mBio ; 13(5): e0214122, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-35997285

RESUMO

Examining the neutralizing capacity of monoclonal antibodies (MAbs) used to treat COVID-19, as well as antibodies recovered from unvaccinated, previously vaccinated, and infected individuals, against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) remains critical to study. Here, we report on a SARS-CoV-2 nosocomial outbreak caused by the SARS-CoV-2 R.1 variant harboring the E484K mutation in a 281-bed psychiatric facility in New Jersey among unvaccinated inpatients and health care professionals (HCPs). A total of 81 inpatients and HCPs tested positive for SARS-Cov-2 by reverse transcription (RT)-PCR from 29 October 9 to 30 November 2020. The R.1 variant exhibits partial or complete resistance to two MAbs in clinical use, as well as 2 receptor binding domain MAbs and 4 N-terminal domain (NTD) MAbs. NTD MAbs against pseudovirus harboring single characteristic R.1 mutations highlight the role of S255F in loss of activity. Additionally, we note dampened neutralization capacity by plasma from individuals with previous SARS-CoV-2 infection or sera from vaccinated individuals. The relative resistance of the R.1 variant is likely lower than that of B.1.351 and closer to that of P.1 and B.1.526. The R.1 lineage has been reported in 47 states in the United States and 40 countries. Although high proportions exhibited symptoms (26% and 61% among patients and HCPs, respectively) and relative antibody resistance, we detected only 10 R.1 variants from over 2,900 samples (~0.34%) collected from January to October 2021. Among 3 vaccinated individuals previously infected with R.1, we observed robust neutralizing antibody responses against SARS-CoV-2 wild type and VOCs. IMPORTANCE The neutralizing capacities of monoclonal antibodies used to treat COVID-19 and of those recovered from previously infected and vaccinated individuals against SARS-CoV-2 variants of concern (VOCs) remain important questions. We report on a nosocomial outbreak caused by a SARS-CoV-2 R.1 variant harboring an E484K mutation among 81 unvaccinated inpatients and health care professionals. We note high attack rates with symptoms in nearly 50% of infected individuals, in sharp contrast to an unrelated institutional outbreak caused by the R.1 variant among a vaccinated population. We found little evidence of significant community spillover. This variant exhibits partial or complete resistance to two monoclonal antibodies in clinical use and dampened the neutralization capacity of convalescent-phase plasma from individuals with previous infection or sera from vaccinated individuals. Among three vaccinated individuals previously infected with R.1, we observed robust neutralizing antibody responses against SARS-CoV-2 wild type and VOCs. These findings underscore the importance of vaccination for prevention of symptomatic COVID-19 disease.


Assuntos
COVID-19 , Infecção Hospitalar , Humanos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , COVID-19/epidemiologia , Testes de Neutralização , Anticorpos Antivirais , New Jersey/epidemiologia , Anticorpos Neutralizantes , Surtos de Doenças , Anticorpos Monoclonais , Genômica
4.
Sci Transl Med ; 14(646): eabn6859, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35438546

RESUMO

The devastation caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has made clear the importance of pandemic preparedness. To address future zoonotic outbreaks due to related viruses in the sarbecovirus subgenus, we identified a human monoclonal antibody, 10-40, that neutralized or bound all sarbecoviruses tested in vitro and protected against SARS-CoV-2 and SARS-CoV in vivo. Comparative studies with other receptor-binding domain (RBD)-directed antibodies showed 10-40 to have the greatest breadth against sarbecoviruses, suggesting that 10-40 is a promising agent for pandemic preparedness. Moreover, structural analyses on 10-40 and similar antibodies not only defined an epitope cluster in the inner face of the RBD that is well conserved among sarbecoviruses but also uncovered a distinct antibody class with a common CDRH3 motif. Our analyses also suggested that elicitation of this class of antibodies may not be overly difficult, an observation that bodes well for the development of a pan-sarbecovirus vaccine.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Humanos , Isotipos de Imunoglobulinas , Glicoproteína da Espícula de Coronavírus
5.
mSystems ; 6(3): e0049221, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34156294

RESUMO

Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) sequence type 9 (ST9) has emerged and disseminated in Asia. It is associated with colonization or infection in both humans and animal hosts; however, the genetic factors underpinning its adaptation to animal and human population remain to be determined. Here, we conducted a genomic analysis of 191 ST9 S. aureus genomes collected from 12 different countries, including 174 genomes retrieved from public databases and 17 sequenced in this study. In silico spa typing, staphylococcal cassette chromosome mec (SCCmec) typing, and antimicrobial resistance and virulence gene mining were conducted, and the temporal phylogenetic signal was assessed by Bayesian inference. Our results point toward a human methicillin-susceptible S. aureus (MSSA) origin of ST9 that evolved approximately 2 centuries ago. Three major genetic events occurred during ST9 host shift from human to animals: the loss of the immune evasion cluster genes (scn, chp, and sak), which were reported to contribute to virulence in human infections, the acquisition of the SaPIbov4-like element-encoding vwb gene, which is an animal-specific virulence factor responsible for the clotting of animal plasma, and the acquisition of antibiotic resistance genes, including SCCmec, quinolone resistance-determining region (QRDR) mutations, and a multidrug resistance genetic element (MDRST9). Evidence of direct transmission of animal-adapted strains to human hosts also suggest that transmission could potentially reshape the resistance and virulence genetic pool in these isolates. The rapid clonal expansion of MDR ST9 strains in mainland China and Taiwan highlights the increasing need for effective surveillance of antibiotic consumption in animal husbandry to control antimicrobial resistance spread. IMPORTANCE Staphylococcus aureus sequence type 9 (ST9) is the main LA-MRSA clone spreading in the Asian continent. It can colonize and cause mild to severe infections both in animal and humans. Previous work described its genotypic characteristics; however, the molecular history of global spread of ST9 strains remains largely unclear. We conducted a detailed analysis of genomic evolution of global ST9 strains and identified key genetic changes associated with its adaptation to specific hosts. Our results suggest that the ST9 clone originated from human-adapted strains, which lost genes related to the evasion of the immune system. The introduction of ST9 strains in animal populations was aligned with the acquisition of animal-specific virulent factors and mobile elements harboring multiple antimicrobial resistance genes, especially in isolates from mainland China and Taiwan.

6.
Emerg Microbes Infect ; 10(1): 994-997, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33977858

RESUMO

Spike protein mutations E484K and N501Y carried by SARS-CoV-2 variants have been associated with concerning changes of the virus, including resistance to neutralizing antibodies and increased transmissibility. While the concerning variants are fast spreading in various geographical areas, identification and monitoring of these variants are lagging far behind, due in large part to the slow speed and insufficient capacity of viral sequencing. In response to the unmet need for a fast and efficient screening tool, we developed a single-tube duplex molecular assay for rapid and simultaneous identification of E484K and N501Y mutations from nasopharyngeal swab (NS) samples within 2.5 h from sample preparation to report. Using this tool, we screened a total of 1135 clinical NS samples collected from COVID patients at 8 hospitals within the Hackensack Meridian Health network in New Jersey between late December 2020 and March 2021. Our data revealed dramatic increases in the frequencies of both E484K and N501Y over time, underscoring the need for continuous epidemiological monitoring.


Assuntos
COVID-19/virologia , Mutação , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/epidemiologia , Genótipo , Humanos , Nasofaringe/virologia , New Jersey/epidemiologia , RNA Viral/química , RNA Viral/genética , Sensibilidade e Especificidade , Sequenciamento Completo do Genoma
7.
J Fungi (Basel) ; 7(7)2021 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-34356931

RESUMO

Fungal infections are common complications of respiratory viral infections and are associated with the increased need for intensive care and elevated mortality. Data regarding microbiological and molecular characteristics of such infections in COVID-19 patients are scarce. Here, we performed a comprehensive analysis, including species identification, antifungal susceptibility testing, molecular resistance determinants analysis, typing, and retrospective clinical data review, of fungal isolates recovered from 19 COVID-19 patients, who were hospitalized at the Hackensack University Medical Center (HUMC) in Hackensack, New Jersey, USA, in the initial phase of the pandemic from April-May 2020. In total, 17 Candida albicans, two C. parapsilosis, and two Aspergillus fumigatus were analyzed. All Candida spp. isolates were susceptible to micafungin and azole drugs (fluconazole, voriconazole, posaconazole, itraconazole, isavuconazole). A. fumigatus isolates were susceptible to micafungin and all triazole drugs except fluconazole (intrinsic resistance). Multilocus sequence typing (MLST) of C. albicans isolates revealed 15 different sequence types (STs), which clustered below the clade-defining limit of p-distance < 0.04. Pulsed-field gel electrophoresis (PFGE) karyotyping revealed no chromosomal rearrangements in these isolates. A. fumigatus isolates were of different, non-related genotypes. We speculate that virus- and drug-induced immunosuppression (94.7% of the patients received corticosteroids), together with prolonged hospital stay (median duration of 29 days) and mechanical ventilation (median duration of 24 days) likely increased the susceptibility to secondary respiratory and bloodstream infections in the studied patient population. The presence of fungi in blood or respiratory tract fluid was a prognosticator for poor clinical outcome, which presented as an 89.5% 30-day mortality in our patient cohort.

8.
Sci Rep ; 11(1): 4389, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33623090

RESUMO

New Jersey was an early epicenter for the COVID-19 pandemic in the United States, yet information on hospitalized COVID-19 patients from this area is scarce. This study aimed to provide data on demographics and clinical features of a hospitalized patient population who were confirmed with infection by our in-house (CDI) real-time reverse-transcription polymerase chain reaction (RT-PCR) test. We included consecutive patients who were admitted to Hackensack Meridian Health system hospitals with laboratory-confirmed diagnoses of COVID-19 at Hackensack University Medical Center by the CDI virus test between March 12, 2020, and April 8, 2020. Clinical data and viral testing results were collected and analyzed for characteristics associated with outcomes, as well as the correlation with viral load. A total of 722 patients were included in the study, with a median age of 63 (interquartile range (IQR), 51-75) and 272 (37.7%) females. Mortality of this case series was 25.8%, with a statistically significant linear increase observed from age 40 to ≥ 80 by 10-year intervals. Viral load, as indicated by the cycle of threshold (Ct) values from the RT-PCR test, was significantly higher in the oldest patient group (≥ 80), and inversely correlated with survival. This is the first report to describe the clinical characteristics and outcomes in a large hospitalized COVID-19 patient series from New Jersey. Findings from this study are valuable to the ongoing response of both nationwide healthcare networks and the medical research community.


Assuntos
COVID-19/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/mortalidade , Técnicas de Laboratório Clínico , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , New Jersey , Estudos Retrospectivos , Testes Sorológicos
9.
Microbiol Spectr ; 9(3): e0188221, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34787439

RESUMO

Emergence of SARS-CoV-2 with high transmission and immune evasion potential, the so-called variants of concern (VOC), is a major concern. We describe the early genomic epidemiology of SARS-CoV-2 recovered from vaccinated health care professionals (HCP). Our postvaccination COVID-19 symptoms-based surveillance program among HCPs in a 17-hospital network identified all vaccinated HCPs who tested positive for COVID-19 after routine screening or after self-reporting. From 1 January 2021 to 30 April 2021, 23,687 HCPs received either mRNA-1273 or BNT162b2 mRNA vaccine. All available postvaccination SARS-CoV-2 samples and a random collection from nonvaccinated patients during the similar time frame were subjected to VOC screening and whole-genome sequencing (WGS). Sixty-two percent (23,697/37,500) of HCPs received at least one vaccine dose, with 60% (22,458) fully vaccinated. We detected 138 (0.58%, 138/23,697) COVID-19 cases, 105 among partially vaccinated and 33 (0.15%, 33/22,458) among fully vaccinated. Five partially vaccinated required hospitalization, four with supplemental oxygen. VOC screening from 16 fully vaccinated HCPs identified 6 (38%) harboring N501Y and 1 (6%) with E484K polymorphisms; percentage of concurrent nonvaccinated samples was 37% (523/1,404) and 20% (284/1,394), respectively. There was an upward trend from January to April for E484K/Q (3% to 26%) and N501Y (1% to 49%). WGS analysis from vaccinated and nonvaccinated individuals indicated highly congruent phylogenies. We did not detect an increased frequency of any receptor-binding domain (RBD)/N-terminal domain (NTD) polymorphism between groups (P > 0.05). Our results support robust protection by vaccination, particularly among recipients of both doses. Despite VOCs accounting for over 40% of SARS-CoV-2 from fully vaccinated individuals, the genomic diversity appears to proportionally represent VOCs among nonvaccinated populations. IMPORTANCE A number of highly effective vaccines have been developed and deployed to combat the COVID-19 pandemic. The emergence and epidemiological dominance of SARS-CoV-2 mutants with high transmission potential and immune evasion properties, the so-called variants of concern (VOC), continue to be a major concern. Whether these VOCs alter the efficacy of the administered vaccines is of great concern and a critical question to study. We describe the initial genomic epidemiology of SARS-CoV-2 recovered from partial/fully vaccinated health care professionals and probe specifically for VOC enrichment. Our findings support the high level of protection provided by full vaccination despite a steep increase in the prevalence of polymorphisms associated with increased transmission potential (N501Y) and immune evasion (E484K) in the nonvaccinated population. Thus, we do not find evidence of VOC enrichment among vaccinated groups. Overall, the genomic diversity of SARS-CoV-2 recovered postvaccination appears to proportionally represent the observed viral diversity within the community.


Assuntos
Vacinas contra COVID-19 , COVID-19/epidemiologia , Estudos Epidemiológicos , Genômica , Pessoal de Saúde , Epidemiologia Molecular , SARS-CoV-2/genética , Vacinação , Vacina de mRNA-1273 contra 2019-nCoV , Adulto , Idoso , Vacina BNT162 , COVID-19/virologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , New Jersey , Pandemias , SARS-CoV-2/classificação , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus , Sequenciamento Completo do Genoma , Adulto Jovem
10.
mSphere ; 6(4): e0048021, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34431691

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs), harboring spike protein N-terminal domain (NTD) or receptor-binding domain (RBD) mutations, exhibit reduced in vitro susceptibility to convalescent-phase serum, commercial antibody cocktails, and vaccine neutralization and have been associated with reinfections. The accumulation of these mutations could be the consequence of intrahost viral evolution due to prolonged infection in immunocompromised hosts. In this study, we document the microevolution of SARS-CoV-2 recovered from sequential tracheal aspirates from an immunosuppressed patient on steroids and convalescent plasma therapy and identify the emergence of multiple NTD and RBD mutations. SARS-CoV-2 genomes from the first swab (day 0) and from three tracheal aspirates (days 7, 21, and 27) were compared at the sequence level. We identified a mixed viral population with five different S protein mutations (141 to 144 deletion, 243 to 244 deletion, E484K, Q493K, and Q493R) at the NTD or RBD region from the second tracheal aspirate sample (day 21) and a predominance of the S protein 141 to 144 LGVY deletion and E484K mutant on day 27. The neutralizing antibodies against various S protein lentiviral pseudovirus mutants, as well as the anti-SARS-CoV-2 total Ig and IgG, showed "U" shape dynamics, in support of the endogenous development of neutralizing antibodies. The patient's compromised immune status, the antirejection regiment, convalescent plasma treatment, and the development of neutralizing antibodies may have resulted in unique selective pressures on the intrahost genomic evolution, and this observation supports the hypotheses that VOCs can independently arise and that immunocompromised patients on convalescent plasma therapy are potential breeding grounds for immune escape mutants. IMPORTANCE Over a year of the COVID-19 pandemic, distinct severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lineages have arisen in multiple geographic areas around the world. SARS-CoV-2 variants of concern (VOCs), i.e., B.1.1.7 (alpha), B.1.351 (beta), P.1 (gamma), and B.1.617.2 (delta), harboring mutations and/or deletions in spike protein N-terminal domain (NTD) or receptor-binding domain (RBD) regions showed evidence of increased transmissibility and disease severity and possible reduced vaccine efficacy. In this study, we report the emergence of five different NTD and RBD mutations in an uncommon SARS-CoV-2 B.1.369 lineage from an immunosuppressed patient undergoing steroid and convalescent plasma therapy. The observation highlighted that VOCs can independently arise in immunocompromised populations undergoing anti-SARS-CoV-2 therapy, and enhanced measures will be required to reduce the transmission.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/terapia , Hospedeiro Imunocomprometido/imunologia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , Humanos , Imunização Passiva , Masculino , Pessoa de Meia-Idade , Mutação/imunologia , Testes de Neutralização/métodos , Pandemias/prevenção & controle , Ligação Proteica/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Soroterapia para COVID-19
11.
Eur J Neurosci ; 31(9): 1561-73, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20525069

RESUMO

A key step in the maturation of glutamate synapses is the developmental speeding of alpha-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor (AMPA-R) kinetics, which occurs via a switch in receptor subtypes. However, the molecular components required for the switch in receptors are unknown. Here, we used the zebrafish preparation to show that activation of protein kinase C (PKC)gamma is necessary for the developmental speeding of AMPA-R kinetics. Targeted knockdown of PKCgamma with an antisense morpholino oligonucleotide [PKCgamma-morpholino (PKCgamma-MO)], prevents the normal speeding up of AMPA-R kinetics in Mauthner cells. PKCgamma-MO-injected embryos are incapable of trafficking AMPA-Rs following application of phorbol 12-myristate 13-acetate or PKCgamma. PKCgamma-MO-injected embryos do not hatch or exhibit the C-start escape response. Increasing synaptic activity (33 h post-fertilization embryos) by application of an elevated K(+) medium or by application of N-methyl-D-aspartate induces rapid PKCgamma-dependent trafficking of fast AMPA-Rs to synapses. Our findings reveal that PKCgamma is a molecular link underlying the developmental speeding of AMPA-Rs in zebrafish Mauthner cells.


Assuntos
Neurônios/fisiologia , Proteína Quinase C/metabolismo , Receptores de AMPA/metabolismo , Rombencéfalo/embriologia , Rombencéfalo/fisiologia , Sinapses/fisiologia , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Transporte Biológico Ativo/fisiologia , Fármacos do Sistema Nervoso Central/farmacologia , Embrião não Mamífero/fisiologia , Potenciais Pós-Sinápticos Excitadores , Técnicas de Silenciamento de Genes , Imuno-Histoquímica , Cinética , N-Metilaspartato/metabolismo , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp , Potássio/metabolismo , Proteína Quinase C/genética , Rombencéfalo/efeitos dos fármacos , Transdução de Sinais , Sinapses/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/farmacologia , Peixe-Zebra/embriologia
12.
Dev Neurosci ; 31(3): 212-22, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19270440

RESUMO

In some cells, the development of voltage-gated channels requires synaptic input, while in others it does not. Here we investigate whether the sodium and potassium currents in the skeletal muscle of zebrafish sofa potato (sop(-/-)) mutants develop normally. Zebrafish sop(-/-) mutants do not express nicotinic acetylcholine receptors at neuromuscular junctions, and therefore do not exhibit synaptic activity in muscle. We find that in both red and white muscle fibers, sop(-/-) mutants are able to support normal potassium current development during early stages of development [1-3 days post fertilization (dpf)], but at 6 dpf the potassium current density is significantly smaller than that in their phenotypically wild-type siblings (sop(+/?)). In contrast, sodium current density is unaffected. The steady-state properties of potassium currents are unaltered in the sop(-/-) mutants, but there is a significant difference in the V(50) of inactivation of sodium currents. This is the first study in zebrafish to investigate activity-dependent mechanisms of ion channel development and our results indicate that some aspects of ion current development in skeletal muscle require synaptic activity, whereas others do not.


Assuntos
Músculo Esquelético/fisiologia , Canais de Potássio/fisiologia , Receptores Nicotínicos/deficiência , Canais de Sódio/fisiologia , Peixe-Zebra/fisiologia , Animais , Embrião não Mamífero , Potenciais da Membrana/fisiologia , Mutação , Técnicas de Patch-Clamp , Receptores Nicotínicos/genética , Proteínas de Peixe-Zebra/genética
13.
Dev Neurobiol ; 76(5): 487-506, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26178704

RESUMO

Fast excitatory synaptic transmission in the CNS is mediated by the neurotransmitter glutamate, binding to and activating AMPA receptors (AMPARs). AMPARs are known to interact with auxiliary proteins that modulate their behavior. One such family of proteins is the transmembrane AMPA receptor-related proteins, known as TARPs. Little is known about the role of TARPs during development, or about their function in non-mammalian organisms. Here we report the presence of TARPs, specifically the prototypical TARP, stargazin, in developing zebrafish. We find that zebrafish express two forms of stargazin, Cacng2a and Cacng2b from as early as 12-h post fertilization (hpf). Knockdown of Cacng2a and Cacng2b via splice-blocking morpholinos resulted in embryos that exhibited deficits in C-start escape responses, showing reduced C-bend angles, smaller tail velocities and aberrant C-bend turning directions. Injection of the morphants with Cacng2a or 2b mRNA rescued the morphological phenotype and the synaptic deficits. To investigate the effect of reduced Cacng2a and 2b levels on synaptic physiology, we performed whole cell patch clamp recordings of AMPA mEPSCs from zebrafish Mauthner cells. Knockdown of Cacng2a results in reduced AMPA currents and lower mEPSC frequencies, whereas knockdown of Cacng2b displayed no significant change in mEPSC amplitude or frequency. Non-stationary fluctuation analysis confirmed a reduction in the number of active synaptic receptors in the Cacng2a but not in the Cacng2b morphants. Together, these results suggest that Cacng2a is required for normal trafficking and function of synaptic AMPARs, while Cacng2b is largely non-functional with respect to the development of AMPA synaptic transmission.


Assuntos
Canais de Cálcio/metabolismo , Neurônios/fisiologia , Receptores de AMPA/metabolismo , Sinapses/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/fisiologia , Processamento Alternativo , Animais , Canais de Cálcio/genética , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Técnicas de Silenciamento de Genes , Potenciais Pós-Sinápticos em Miniatura/efeitos dos fármacos , Morfolinos , Atividade Motora/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Técnicas de Patch-Clamp , RNA Mensageiro/metabolismo , Rombencéfalo/embriologia , Rombencéfalo/metabolismo , Rombencéfalo/patologia , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos , Sinapses/patologia , Proteínas de Peixe-Zebra/genética
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