RESUMO
Respiratory syncytial virus (RSV) is the most important viral agent of severe pediatric respiratory illness worldwide, but there is no approved pediatric vaccine. Here, we describe the development of the live-attenuated RSV vaccine candidate Min AL as well as engineered derivatives. Min AL was attenuated by codon-pair deoptimization (CPD) of seven of the 11 RSV open reading frames (ORFs) (NS1, NS2, N, P, M, SH and L; 2,073 silent nucleotide substitutions in total). Min AL replicated efficiently in vitro at the permissive temperature of 32°C but was highly temperature sensitive (shut-off temperature of 36°C). When serially passaged at increasing temperatures, Min AL retained greater temperature sensitivity compared to previous candidates with fewer CPD ORFs. However, whole-genome deep-sequencing of passaged Min AL revealed mutations throughout its genome, most commonly missense mutations in the polymerase cofactor P and anti-termination transcription factor M2-1 (the latter was not CPD). Reintroduction of selected mutations into Min AL partially rescued its replication in vitro at temperatures up to 40°C, confirming their compensatory effect. These mutations restored the accumulation of positive-sense RNAs to wild-type (wt) RSV levels, suggesting increased activity by the viral transcriptase, whereas viral protein expression, RNA replication, and virus production were only partly rescued. In hamsters, Min AL and derivatives remained highly restricted in replication in the upper and lower airways, but induced serum IgG and IgA responses to the prefusion form of F (pre F) that were comparable to those induced by wt RSV, as well as robust mucosal and systemic IgG and IgA responses against RSV G. Min AL and derivatives were fully protective against challenge virus replication. The derivatives had increased genetic stability compared to Min AL. Thus, Min AL and derivatives with selected mutations are stable, attenuated, yet highly-immunogenic RSV vaccine candidates that are available for further evaluation.
Assuntos
Fases de Leitura Aberta , Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Vacinas Atenuadas , Replicação Viral , Animais , Vacinas contra Vírus Sincicial Respiratório/imunologia , Vacinas contra Vírus Sincicial Respiratório/genética , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/genética , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Infecções por Vírus Respiratório Sincicial/virologia , Cricetinae , Administração Intranasal , Códon , Imunidade nas Mucosas , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Humanos , Vírus Sincicial Respiratório Humano/imunologia , Vírus Sincicial Respiratório Humano/genética , Mesocricetus , Vírus Sinciciais Respiratórios/imunologia , Vírus Sinciciais Respiratórios/genéticaRESUMO
DNA polymerase stalling activates the ATR checkpoint kinase, which in turn suppresses fork collapse and breakage. Herein, we describe use of ATR inhibition (ATRi) as a means to identify genomic sites of problematic DNA replication in murine and human cells. Over 500 high-resolution ATR-dependent sites were ascertained using two distinct methods: replication protein A (RPA)-chromatin immunoprecipitation (ChIP) and breaks identified by TdT labeling (BrITL). The genomic feature most strongly associated with ATR dependence was repetitive DNA that exhibited high structure-forming potential. Repeats most reliant on ATR for stability included structure-forming microsatellites, inverted retroelement repeats, and quasi-palindromic AT-rich repeats. Notably, these distinct categories of repeats differed in the structures they formed and their ability to stimulate RPA accumulation and breakage, implying that the causes and character of replication fork collapse under ATR inhibition can vary in a DNA-structure-specific manner. Collectively, these studies identify key sources of endogenous replication stress that rely on ATR for stability.
Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/genética , Replicação do DNA/genética , Repetições de Microssatélites/genética , Animais , Proteínas de Ciclo Celular/genética , Cromatina/genética , Imunoprecipitação da Cromatina/métodos , Quebras de DNA de Cadeia Dupla , Dano ao DNA/genética , Feminino , Instabilidade Genômica/genética , Humanos , Camundongos , Proteína de Replicação A/genéticaRESUMO
Preeclampsia is a multi-organ complication of pregnancy characterized by sudden hypertension and proteinuria that is among the leading causes of preterm delivery and maternal morbidity and mortality worldwide. The heterogeneity of preeclampsia poses a challenge for understanding its etiology and molecular basis. Intriguingly, risk for the condition increases in high-altitude regions such as the Peruvian Andes. To investigate the genetic basis of preeclampsia in a population living at high altitude, we characterized genome-wide variation in a cohort of preeclamptic and healthy Andean families (n = 883) from Puno, Peru, a city located above 3,800 meters of altitude. Our study collected genomic DNA and medical records from case-control trios and duos in local hospital settings. We generated genotype data for 439,314 SNPs, determined global ancestry patterns, and mapped associations between genetic variants and preeclampsia phenotypes. A transmission disequilibrium test (TDT) revealed variants near genes of biological importance for placental and blood vessel function. The top candidate region was found on chromosome 13 of the fetal genome and contains clotting factor genes PROZ, F7, and F10. These findings provide supporting evidence that common genetic variants within coagulation genes play an important role in preeclampsia. A selection scan revealed a potential adaptive signal around the ADAM12 locus on chromosome 10, implicated in pregnancy disorders. Our discovery of an association in a functional pathway relevant to pregnancy physiology in an understudied population of Native American origin demonstrates the increased power of family-based study design and underscores the importance of conducting genetic research in diverse populations.
Assuntos
Pré-Eclâmpsia , Altitude , Fatores de Coagulação Sanguínea , Proteínas Sanguíneas/genética , Estudos de Casos e Controles , Fator VII/genética , Fator X/genética , Feminino , Humanos , Peru/epidemiologia , Placenta , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/genética , GravidezRESUMO
INTRODUCTION: For patients with locally advanced triple negative breast cancer (TNBC), the standard of care is to administer the KEYNOTE-522 (K522) regimen, including chemotherapy and immunotherapy (pembrolizumab) given in the neoadjuvant setting. Pathological complete response (pCR) is more likely in patients who receive the K522 regimen than in patients who receive standard chemotherapy. Studies have shown that pCR is a strong predictor of long-term disease-free survival. However, factors predicting pCR to K522 are not well understood and require further study in real-world populations. METHODS: We evaluated 76 patients who were treated with the K522 regimen at our institution. Twenty-nine pre-treatment biopsy slides were available for pathology review. Nuclear grade, Nottingham histologic grade, Ki-67, lymphovascular invasion, and tumor infiltrating lymphocytes (TIL) were evaluated in these 29 cases. For the cases that did not have available slides for review from pre-treatment biopsies, these variables were retrieved from available pathology reports. In addition, clinical staging, race, and BMI at the time of biopsy were retrieved from all 76 patients' charts. Binary logistic regression models were used to correlate these variables with pCR. RESULTS: At the current time, 64 of 76 patients have undergone surgery at our institution following completion of K522 and 31 (48.4%) of these achieved pCR. In univariate analysis, only TIL was significantly associated with pCR (p = 0.014) and this finding was also confirmed in multivariate analysis, whereas other variables including age, race, nuclear grade, Nottingham grade, Ki-67, lymphovascular invasion, BMI, pre-treatment tumor size, and lymph node status were not associated with pCR (p > 0.1). CONCLUSION: Our real-world data demonstrates high TIL is significantly associated with pCR rate in the K522 regimen and may potentially serve as a biomarker to select optimal treatment. The pCR rate of 48.4% in our study is lower than that reported in K522, potentially due to the smaller size of our study; however, this may also indicate differences between real-world data and clinical trial results. Larger studies are warranted to further investigate the role of immune cells in TNBC response to K522 and other treatment regimens.
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Linfócitos do Interstício Tumoral , Terapia Neoadjuvante , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/terapia , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Feminino , Terapia Neoadjuvante/métodos , Pessoa de Meia-Idade , Adulto , Idoso , Resultado do Tratamento , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Estadiamento de Neoplasias , Imunoterapia/métodos , Gradação de Tumores , PrognósticoRESUMO
Animal contact is an established risk factor for nontyphoidal Salmonella infections and outbreaks. During 2015-2018, the U.S. Centers for Disease Control and Prevention (CDC) and other U.S. public health laboratories began implementing whole-genome sequencing (WGS) of Salmonella isolates. WGS was used to supplement the traditional methods of pulsed-field gel electrophoresis for isolate subtyping, outbreak detection, and antimicrobial susceptibility testing (AST) for the detection of resistance. We characterized the epidemiology and antimicrobial resistance (AMR) of multistate salmonellosis outbreaks linked to animal contact during this time period. An isolate was considered resistant if AST yielded a resistant (or intermediate, for ciprofloxacin) interpretation to any antimicrobial tested by the CDC or if WGS showed a resistance determinant in its genome for one of these agents. We identified 31 outbreaks linked to contact with poultry (n = 23), reptiles (n = 6), dairy calves (n = 1), and guinea pigs (n = 1). Of the 26 outbreaks with resistance data available, we identified antimicrobial resistance in at least one isolate from 20 outbreaks (77%). Of 1,309 isolates with resistance information, 247 (19%) were resistant to ≥1 antimicrobial, and 134 (10%) were multidrug-resistant to antimicrobials from ≥3 antimicrobial classes. The use of resistance data predicted from WGS increased the number of isolates with resistance information available fivefold compared with AST, and 28 of 43 total resistance patterns were identified exclusively by WGS; concordance was high (>99%) for resistance determined by AST and WGS. The use of predicted resistance from WGS enhanced the characterization of the resistance profiles of outbreaks linked to animal contact by providing resistance information for more isolates.
Assuntos
Salmonelose Animal , Infecções por Salmonella , Animais , Bovinos , Estados Unidos/epidemiologia , Cobaias , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções por Salmonella/epidemiologia , Aves Domésticas , Surtos de Doenças , Testes de Sensibilidade Microbiana , Salmonelose Animal/epidemiologiaRESUMO
The impact of vaccination on SARS-CoV-2 infectiousness is not well understood. We compared longitudinal viral shedding dynamics in unvaccinated and fully vaccinated adults. SARS-CoV-2-infected adults were enrolled within 5 days of symptom onset and nasal specimens were self-collected daily for two weeks and intermittently for an additional two weeks. SARS-CoV-2 RNA load and infectious virus were analyzed relative to symptom onset stratified by vaccination status. We tested 1080 nasal specimens from 52 unvaccinated adults enrolled in the pre-Delta period and 32 fully vaccinated adults with predominantly Delta infections. While we observed no differences by vaccination status in maximum RNA levels, maximum infectious titers and the median duration of viral RNA shedding, the rate of decay from the maximum RNA load was faster among vaccinated; maximum infectious titers and maximum RNA levels were highly correlated. Furthermore, amongst participants with infectious virus, median duration of infectious virus detection was reduced from 7.5 days (IQR: 6.0-9.0) in unvaccinated participants to 6 days (IQR: 5.0-8.0) in those vaccinated (P = 0.02). Accordingly, the odds of shedding infectious virus from days 6 to 12 post-onset were lower among vaccinated participants than unvaccinated participants (OR 0.42 95% CI 0.19-0.89). These results indicate that vaccination had reduced the probability of shedding infectious virus after 5 days from symptom onset.
Assuntos
COVID-19 , SARS-CoV-2 , Adulto , COVID-19/prevenção & controle , Humanos , Estudos Longitudinais , RNA Viral/genética , Vacinação , Eliminação de Partículas ViraisRESUMO
BACKGROUND AND OBJECTIVE: COVID-19 led to an unprecedented reliance on virtual modalities to maintain care continuity for patients living with chronic pain. We examined whether there were disparities in virtual specialty pain care for racial-ethnic minority groups during COVID-19. DESIGN AND PARTICIPANTS: This was a retrospective national cohort study with two comparison groups: primary care patients with chronic pain seen immediately prior to COVID-19 (3/1/19-2/29/20) (N = 1,649,053) and a cohort of patients seen in the year prior (3/1/18-2/28-19; n = 1,536,954). MAIN MEASURES: We assessed use of telehealth (telephone or video) specialty pain care, in-person care specialty pain care, and any specialty pain care for both groups at 6 months following cohort inclusion. We used quasi-Poisson regressions to test associations between patient race and ethnicity and receipt of care. KEY RESULTS: Prior to COVID-19, there were Black-White (RR = 0.64, 95% CI [0.62, 0.67]) and Asian-White (RR = 0.63, 95% CI [0.54, 0.75]) disparities in telehealth use, and these lessened during COVID-19 (Black-White: RR = 0.75, 95% CI [0.73, 0.77], Asian-White: RR = 0.81, 95% CI [0.74, 0.89]) but did not disappear. Individuals identifying as American Indian/Alaska Native used telehealth less than White individuals during early COVID-19 (RR = 0.98, 95% CI [0.85, 1.13] to RR = 0.87, 95% CI [0.79, 0.96]). Hispanic/Latinx individuals were less likely than non-Hispanic/Latinx individuals to use telehealth prior to COVID-19 but more likely during early COVID-19 (RR = 0.70, 95% CI [0.66, 0.75] to RR = 1.06, 95% CI [1.02, 1.09]). Disparities in virtual pain care occurred over the backdrop of overall decreased specialty pain care during the early phase of the pandemic (raw decrease of n = 17,481 specialty care encounters overall from pre-COVID to COVID-era), including increased disparities in any VA specialty pain care for Black (RR = 0.81, 95% CI [0.80, 0.83] to RR = 0.79, 95% CI [0.77, 0.80]) and Asian (RR = 0.91, 95% CI [0.86, 0.97] to RR = 0.88, 95% CI [0.82, 0.94]) individuals. CONCLUSIONS: Disparities in virtual specialty pain care were smaller during the early phases of the COVID-19 pandemic than prior to the pandemic but did not disappear entirely, despite the rapid growth in telehealth. Targeted efforts to increase access to specialty pain care need to be concentrated among racial-ethnic minority groups.
Assuntos
COVID-19 , Dor Crônica , Humanos , Estados Unidos , Etnicidade , Estudos de Coortes , Estudos Retrospectivos , Pandemias , Minorias Étnicas e Raciais , Grupos Minoritários , BrancosRESUMO
BACKGROUND: Opioid use disorder (OUD) care engagement rates in primary care (PC) settings are often low. Little is known about PC team experiences when delivering OUD treatment and potential factors that influence their capacity to engage patients in treatment. Exploring PC team experiences may inform needed supports that can optimize OUD care delivery and improve outcomes for patients with OUD. OBJECTIVE: We explored multidisciplinary PC team perspectives on barriers and facilitators to engaging patients in OUD treatment. DESIGN: Qualitative study using in-depth interviews. PARTICIPANTS: Primary care clinical teams. APPROACH: We conducted semi-structured interviews (n = 35) with PC team members involved in OUD care delivery, recruited using a combination of criterion and maximal variation sampling. Data collection and analysis were informed by existing theoretical literature about patient engagement, specifically that patient engagement is influenced by factors across individual (patient, provider), interpersonal (patient-provider), and health system domains. Interviews were professionally transcribed and doubled-coded using a coding schema based on the interview guide while allowing for emergent codes. Coding was iteratively reviewed using a constant comparison approach to identify themes and verified with participants and the full study team. KEY RESULTS: Analysis identified five themes that impact PC team ability to engage patients effectively, including limited patient contact (e.g., phone, text) in between visits, varying levels of provider confidence to navigate OUD treatment discussions, structural factors (e.g., schedules, productivity goals) that limited provider time, the role of team-based approaches in lessening discouragement and feelings of burnout, and lack of shared organizational vision for reducing harms from OUD. CONCLUSIONS: While the capacity of PC teams to engage patients in OUD care is influenced across multiple levels, some of the most promising opportunities may involve addressing system-level factors that limit PC team time and collaboration and promoting organizational alignment on goals for OUD treatment.
RESUMO
Enteric bacterial infections are common among people who travel internationally. During 2017-2020, the Centers for Disease Control and Prevention investigated 41 multistate outbreaks of nontyphoidal Salmonella and Shiga toxin-producing Escherichia coli linked to international travel. Resistance to one or more antimicrobial agents was detected in at least 10% of isolates in 16 of 30 (53%) nontyphoidal Salmonella outbreaks and 8 of 11 (73%) Shiga toxin-producing E. coli outbreaks evaluated by the National Antimicrobial Resistance Monitoring System. At least 10% of the isolates in 14 nontyphoidal Salmonella outbreaks conferred resistance to one or more of the clinically significant antimicrobials used in human medicine. This report describes the epidemiology and antimicrobial resistance patterns of these travel-associated multistate outbreaks. Investigating illnesses among returned travellers and collaboration with international partners could result in the implementation of public health interventions to improve hygiene practices and food safety standards and to prevent illness and spread of multidrug-resistant organisms domestically and internationally.
Assuntos
Anti-Infecciosos , Infecções por Escherichia coli , Escherichia coli Shiga Toxigênica , Humanos , Estados Unidos/epidemiologia , Viagem , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Salmonella , Surtos de DoençasRESUMO
BACKGROUND: Antimicrobial resistance in nontyphoidal Salmonella (NTS) can limit treatment options. We assessed the contribution of international travel to antimicrobial-resistant NTS infections. METHODS: We describe NTS infections that were reported to the Foodborne Diseases Active Surveillance Network during 2018-2019 and screened for genetic resistance determinants, including those conferring decreased susceptibility to first-line agents (ciprofloxacin, ceftriaxone, or azithromycin). We used multivariable logistic regression to assess the association between resistance and international travel during the 7 days before illness began. We estimated the contribution of international travel to resistance using population-attributable fractions, and we examined reported antimicrobial use. RESULTS: Among 9301 NTS infections, 1159 (12%) occurred after recent international travel. Predicted resistance to first-line antimicrobials was more likely following travel; the adjusted odds ratio varied by travel region and was highest after travel to Asia (adjusted odds ratio, 7.2 [95% confidence interval, 5.5-9.5]). Overall, 19% (95% confidence interval, 17%-22%) of predicted resistance to first-line antimicrobials was attributable to international travel. More travelers than nontravelers receiving ciprofloxacin or other fluoroquinolones had isolates with predicted resistance to fluoroquinolones (29% vs 9%, respectively; P < .01). CONCLUSIONS: International travel is a substantial risk factor for antimicrobial-resistant NTS infections. Understanding risks of resistant infection could help target prevention efforts.
Assuntos
Anti-Infecciosos , Infecções por Salmonella , Humanos , Estados Unidos/epidemiologia , Testes de Sensibilidade Microbiana , Infecções por Salmonella/tratamento farmacológico , Infecções por Salmonella/epidemiologia , Salmonella/genética , Ciprofloxacina/farmacologia , Ciprofloxacina/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêuticoRESUMO
The adult zebrafish brain, unlike mammals, has a remarkable regenerative capacity. Although inflammation in part hinders regeneration in mammals, it is necessary for zebrafish brain repair. Microglia are resident brain immune cells that regulate the inflammatory response. To explore the microglial role in repair, we used liposomal clodronate or colony stimulating factor-1 receptor (csf1r) inhibitor to suppress microglia after brain injury, and also examined regeneration in two genetic mutant lines that lack microglia. We found that microglial ablation impaired telencephalic regeneration after injury. Microglial suppression attenuated cell proliferation at the intermediate progenitor cell amplification stage of neurogenesis. Notably, the loss of microglia impaired phospho-Stat3 (signal transducer and activator of transcription 3) and ß-Catenin signaling after injury. Furthermore, the ectopic activation of Stat3 and ß-Catenin rescued neurogenesis defects caused by microglial loss. Microglial suppression also prolonged the post-injury inflammatory phase characterized by neutrophil accumulation, likely hindering the resolution of inflammation. These findings reveal specific roles of microglia and inflammatory signaling during zebrafish telencephalic regeneration that should advance strategies to improve mammalian brain repair.
Assuntos
Lesões Encefálicas , Microglia , Animais , Peixe-Zebra , Encéfalo , Neurogênese , Inflamação , Cateninas , MamíferosRESUMO
Reports of Salmonella enterica I serotype 4,[5],12:i:- infections resistant to ampicillin, streptomycin, sulphamethoxazole, and tetracycline (ASSuT) have been increasing. We analyzed data from 5 national surveillance systems to describe the epidemiology, resistance traits, and genetics of infections with this Salmonella strain in the United States. We found ASSuT-resistant Salmonella 4,[5],12:i:- increased from 1.1% of Salmonella infections during 2009-2013 to 2.6% during 2014-2018; the proportion of Salmonella 4,[5],12:i:- isolates without this resistance pattern declined from 3.1% to 2.4% during the same timeframe. Among isolates sequenced during 2015-2018, a total of 69% were in the same phylogenetic clade. Within that clade, 77% of isolates had genetic determinants of ASSuT resistance, and 16% had genetic determinants of decreased susceptibility to ciprofloxacin, ceftriaxone, or azithromycin. Among outbreaks related to the multidrug-resistant clade, 63% were associated with pork consumption or contact with swine. Preventing Salmonella 4,[5],12:i:- carriage in swine would likely avert human infections with this strain.
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Carne de Porco , Carne Vermelha , Salmonella enterica , Estados Unidos/epidemiologia , Animais , Humanos , Suínos , Sorogrupo , Filogenia , Farmacorresistência Bacteriana Múltipla/genética , Antibacterianos/farmacologia , Salmonella , Testes de Sensibilidade MicrobianaRESUMO
Genomic characterization of an Escherichia coli O157:H7 strain linked to leafy greens-associated outbreaks dates its emergence to late 2015. One clade has notable accessory genomic content and a previously described mutation putatively associated with increased arsenic tolerance. This strain is a reoccurring, emerging, or persistent strain causing illness over an extended period.
Assuntos
Escherichia coli O157 , Escherichia coli O157/genética , Surtos de Doenças , Genômica , MutaçãoRESUMO
Tendons and ligaments are crucial components of the musculoskeletal system, yet the pathways specifying these fates remain poorly defined. Through a screen of known bioactive chemicals in zebrafish, we identified a new pathway regulating tendon cell induction. We established that statin, through inhibition of the mevalonate pathway, causes an expansion of the tendon progenitor population. Co-expression and live imaging studies indicate that the expansion does not involve an increase in cell proliferation, but rather results from re-specification of cells from the neural crest-derived sox9a+/sox10+ skeletal lineage. The effect on tendon cell expansion is specific to the geranylgeranylation branch of the mevalonate pathway and is mediated by inhibition of Rac activity. This work establishes a novel role for the mevalonate pathway and Rac activity in regulating specification of the tendon lineage.
Assuntos
Ácido Mevalônico/metabolismo , Tendões/metabolismo , Alquil e Aril Transferases/antagonistas & inibidores , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Animais , Animais Geneticamente Modificados/metabolismo , Atorvastatina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Farnesiltranstransferase/antagonistas & inibidores , Farnesiltranstransferase/genética , Farnesiltranstransferase/metabolismo , Morfolinos/metabolismo , Crista Neural/metabolismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Fatores de Transcrição SOXE/genética , Fatores de Transcrição SOXE/metabolismo , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/metabolismo , Tendões/citologia , Tendões/patologia , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/antagonistas & inibidores , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Proteínas rac de Ligação ao GTP/antagonistas & inibidores , Proteínas rac de Ligação ao GTP/metabolismoRESUMO
Recoding viral genomes by introducing numerous synonymous nucleotide substitutions that create suboptimal codon pairs provides new live-attenuated vaccine candidates. Because recoding typically involves a large number of nucleotide substitutions, the risk of de-attenuation is presumed to be low. However, this has not been thoroughly studied. We previously generated human respiratory syncytial virus (RSV) in which the NS1, NS2, N, P, M and SH ORFs were codon-pair deoptimized (CPD) by 695 synonymous nucleotide changes (Min A virus). Min A exhibited a global reduction in transcription and protein synthesis, was restricted for replication in vitro and in vivo, and exhibited moderate temperature sensitivity. Here, we show that under selective pressure by serial passage at progressively increasing temperatures, Min A regained replication fitness and lost its temperature sensitivity. Whole-genome deep sequencing identified numerous missense mutations in several genes, in particular ones accumulating between codons 25 and 34 of the phosphoprotein (P), a polymerase cofactor and chaperone. When re-introduced into Min A, these P mutations restored viral transcription to wt level, resulting in increased protein expression and RNA replication. Molecular dynamic simulations suggested that these P mutations increased the flexibility of the N-terminal domain of P, which might facilitate its interaction with the nucleoprotein N, and increase the functional efficiency of the RSV transcription/replication complex. Finally, we evaluated the effect of the P mutations on Min A replication and immunogenicity in hamsters. Mutation P[F28V] paradoxically reduced Min A replication but not its immunogenicity. The further addition of one missense mutation each in M and L generated a version of Min A with increased genetic stability. Thus, this study provides further insight into the adaptability of large-scale recoded RNA viruses under selective pressure and identified an improved CPD RSV vaccine candidate.
Assuntos
Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano/genética , Proteínas Estruturais Virais/genética , Animais , Chlorocebus aethiops , Cricetinae , Mesocricetus , Mutação , Fosfoproteínas/genética , Transcrição Gênica , Vacinas Atenuadas , Células VeroRESUMO
OBJECTIVE: As SARS-CoV-2 is known to invade neural cell mitochondria, a plasma system for quantifying central nervous system proteins in living humans was used to investigate neuropathogenic mechanisms of long-COVID-19. METHODS: SARS-CoV-2 proteins and mitochondrial proteins (MPs) in enriched plasma neuron-derived extracellular vesicles (NDEVs) and astrocyte-derived EVs (ADEVs) were quantified in resolved acute COVID-19 without post-acute sequelae of SARS-CoV-2 (PASC), PASC without neuropsychiatric manifestations (NP), PASC with NP and healthy controls. RESULTS: NDEV and ADEV mean levels of SARS-CoV-2 S1 and nucleocapsid (N) proteins were higher in all PASC sub-groups than controls, but only N levels were higher in PASC with than without NP. Exosome marker CD81-normalized NDEV mean levels of subunit 6 of MP respiratory chain complex I and subunit 10 of complex III, and neuroprotective MPs Humanin and mitochondrial open-reading frame of the 12S rRNA-c (MOTS-c) all were decreased significantly in PASC with NP but not in PASC without NP relative to controls. NDEV levels of MPs voltage-dependent anion-selective channel protein 1 (VDAC1) and N-methyl-D-aspartate receptor 1 (NMDAR1) were decreased in PASC without and with NP, whereas those of calcium channel MPs mitochondrial calcium uniporter (MCU), sodium/calcium exchanger (NCLX) and leucine zipper EF-hand containing transmembrane 1 protein (LETM1) were decreased only in PASC with NP. ADEV levels of MCU and NCLX only were increased in PASC without and with NP. INTERPRETATION: Abnormal NDEV and ADEV levels of SARS-CoV-2 N and S1 protein and MPs correlate with NP and may be biomarkers for long-COVID prognostics and therapeutic trials. ANN NEUROL 2022;91:772-781.
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COVID-19 , Exossomos , Biomarcadores , COVID-19/complicações , Progressão da Doença , Exossomos/metabolismo , Humanos , Proteínas de Membrana , Proteínas Mitocondriais , SARS-CoV-2 , Síndrome de COVID-19 Pós-AgudaRESUMO
Artificial light at night (ALAN) is increasingly prevalent worldwide, but life-history strategy may mitigate the costs of ALAN for animals. Yet, interactions among ALAN, life-history strategy and tolerance to climate-related stressors are unknown. We determined if developmental ALAN exposure (1) affects development, (2) affects adult phenotype, including heat and desiccation tolerance, and (3) affects and/or interacts with life-history strategy. We used the variable field cricket (Gryllus lineaticeps) because its geographic range is increasingly exposed to ALAN, heat, and drought conditions, and it exhibits different life-history strategies (flight-capability versus flight-incapability). ALAN affected adult phenotype, with positive effects on body mass (and size) and female reproductive investment, and a negative effect on heat tolerance. Life-history strategy also affected stress tolerance; flight-incapable females had greater heat tolerance and their desiccation tolerance was improved by ALAN exposure. Key features of environmental change (i.e. exposure to ALAN, heat and drought) may favor some life-history strategies over others.
Assuntos
Gryllidae , Luz , Animais , Feminino , Poluição Luminosa , ReproduçãoRESUMO
An effectiveness trial found that telemedicine collaborative care for posttraumatic stress disorder (PTSD) significantly increased engagement in trauma-focused psychotherapy (TFP) and improved PTSD symptoms. However, in a subsequent implementation trial, very few veterans enrolled in collaborative care initiated TFP. We conducted a mixed-methods evaluation to determine why veterans did not initiate TFP in the implementation trial. After conducting chart reviews of 1,071 veterans with PTSD enrolled in collaborative care, patients were categorized into four mutually exclusive TFP groups: TFP not discussed; TFP discussed, declined; TFP discussed, did not decline; and TFP initiated. We conducted semistructured interviews with 43 unique patients and 58 unique providers (i.e., care managers and mental health specialists). Almost half (48.6%) of the veterans had no documentation of discussing TFP with their care manager; another 28.9% discussed it but declined. Most veterans (77.1%) had an encounter with a mental health specialist, 36.8% of whom never discussed TFP, and 35.7% of whom discussed it but declined. Providers reported that many veterans were not able, willing, or ready to engage in TFP and that non-trauma-focused therapies were better aligned with their treatment goals. Veterans gave numerous reasons for not initiating TFP, including having bad prior experiences with TFP and wanting to avoid thinking about past traumatic experiences. Commonly cited reasons for noninitiation were providers never discussing TFP with veterans and veterans declining TFP after discussing it with their provider. Interventions, such as shared decision-making tools, may be needed to engage providers and patients in informed discussions about TFP.
Assuntos
Transtornos de Estresse Pós-Traumáticos , Telemedicina , Veteranos , Humanos , Saúde Mental , Psicoterapia/métodos , Transtornos de Estresse Pós-Traumáticos/terapia , Transtornos de Estresse Pós-Traumáticos/psicologia , Telemedicina/métodos , Veteranos/psicologiaRESUMO
BACKGROUND: RNA N6-methyladenosine (m6A) is the most common type of modification in eukaryotic mRNA. The relationship between m6A modification and disease has been studied extensively, but there have been few studies on chronic heart failure (CHF). This study investigated a possible role for m6A in the diagnosis of CHF. METHODS: Seven candidate m6A regulators (writers: WTAP and ZC3H13; readers: YTHDF3, FMR1, IGFBP1, and ELAVL1; eraser: FTO) were identified using a random forest (RF) model and the GSE5406 dataset from the Gene Expression Omnibus database. A nomogram model was developed to predict the risk of CHF, while consensus clustering methodology assigned CHF samples into two m6A patterns (cluster A and cluster B) according to the 7 candidate m6A regulators. Principal component analysis was used to calculate an m6A score for each sample and to quantify m6A patterns. RESULTS: Decision curve analysis and the nomogram model were used to obtain predictions that may be of clinical use. Patients in cluster B had higher m6A scores than patients in cluster A. Cluster B patients also had higher expression levels (ELs) of IL-4, IL-5, IL-10 and IL-13 than patients in cluster A, whereas cluster A patients had a higher EL for IL-33. The m6A cluster B pattern likely represents the ischemic heart failure (HF) disease group. CONCLUSION: m6A regulators are important in the pathogenesis of CHF associated with ischemic and idiopathic dilated cardiomyopathy, and may prove useful for the diagnosis and treatment of CHF.
Assuntos
Cardiomiopatia Dilatada , Insuficiência Cardíaca , Humanos , Genes Reguladores , Doença Crônica , Bases de Dados Factuais , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/genética , Proteína do X Frágil da Deficiência Intelectual , Dioxigenase FTO Dependente de alfa-CetoglutaratoRESUMO
Spinal cord injury (SCI) often causes loss of sensory and motor function resulting in a significant reduction in quality of life for patients. Currently, no therapies are available that can repair spinal cord tissue. After the primary SCI, an acute inflammatory response induces further tissue damage in a process known as secondary injury. Targeting secondary injury to prevent additional tissue damage during the acute and subacute phases of SCI represents a promising strategy to improve patient outcomes. Here, we review clinical trials of neuroprotective therapeutics expected to mitigate secondary injury, focusing primarily on those in the last decade. The strategies discussed are broadly categorized as acute-phase procedural/surgical interventions, systemically delivered pharmacological agents, and cell-based therapies. In addition, we summarize the potential for combinatorial therapies and considerations.