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1.
N Engl J Med ; 386(21): 2011-2023, 2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35544369

RESUMO

BACKGROUND: Vaccination of children to prevent coronavirus disease 2019 (Covid-19) is an urgent public health need. The safety, immunogenicity, and efficacy of the mRNA-1273 vaccine in children 6 to 11 years of age are unknown. METHODS: Part 1 of this ongoing phase 2-3 trial was open label for dose selection; part 2 was an observer-blinded, placebo-controlled expansion evaluation of the selected dose. In part 2, we randomly assigned children (6 to 11 years of age) in a 3:1 ratio to receive two injections of mRNA-1273 (50 µg each) or placebo, administered 28 days apart. The primary objectives were evaluation of the safety of the vaccine in children and the noninferiority of the immune response in these children to that in young adults (18 to 25 years of age) in a related phase 3 trial. Secondary objectives included determination of the incidences of confirmed Covid-19 and severe acute respiratory syndrome coronavirus 2 infection, regardless of symptoms. Interim analysis results are reported. RESULTS: In part 1 of the trial, 751 children received 50-µg or 100-µg injections of the mRNA-1273 vaccine, and on the basis of safety and immunogenicity results, the 50-µg dose level was selected for part 2. In part 2 of the trial, 4016 children were randomly assigned to receive two injections of mRNA-1273 (50 µg each) or placebo and were followed for a median of 82 days (interquartile range, 14 to 94) after the first injection. This dose level was associated with mainly low-grade, transient adverse events, most commonly injection-site pain, headache, and fatigue. No vaccine-related serious adverse events, multisystem inflammatory syndrome in children, myocarditis, or pericarditis were reported as of the data-cutoff date. One month after the second injection (day 57), the neutralizing antibody titer in children who received mRNA-1273 at a 50-µg level was 1610 (95% confidence interval [CI], 1457 to 1780), as compared with 1300 (95% CI, 1171 to 1443) at the 100-µg level in young adults, with serologic responses in at least 99.0% of the participants in both age groups, findings that met the prespecified noninferiority success criterion. Estimated vaccine efficacy was 88.0% (95% CI, 70.0 to 95.8) against Covid-19 occurring 14 days or more after the first injection, at a time when B.1.617.2 (delta) was the dominant circulating variant. CONCLUSIONS: Two 50-µg doses of the mRNA-1273 vaccine were found to be safe and effective in inducing immune responses and preventing Covid-19 in children 6 to 11 years of age; these responses were noninferior to those in young adults. (Funded by the Biomedical Advanced Research and Development Authority and the National Institute of Allergy and Infectious Diseases; KidCOVE ClinicalTrials.gov number, NCT04796896.).


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV , COVID-19 , Vacina de mRNA-1273 contra 2019-nCoV/efeitos adversos , Vacina de mRNA-1273 contra 2019-nCoV/imunologia , Vacina de mRNA-1273 contra 2019-nCoV/uso terapêutico , Adolescente , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/complicações , COVID-19/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/uso terapêutico , Criança , Método Duplo-Cego , Humanos , SARS-CoV-2 , Síndrome de Resposta Inflamatória Sistêmica , Eficácia de Vacinas , Adulto Jovem
2.
Proc Natl Acad Sci U S A ; 119(29): e2205498119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858344

RESUMO

HLA class I (HLA-I) allotypes vary widely in their dependence on tapasin (TAPBP), an integral component of the peptide-loading complex, to present peptides on the cell surface. We identified two single-nucleotide polymorphisms that regulate TAPBP messenger RNA (mRNA) expression in Africans, rs111686073 (G/C) and rs59097151 (A/G), located in an AP-2α transcription factor binding site and a microRNA (miR)-4486 binding site, respectively. rs111686073G and rs59097151A induced significantly higher TAPBP mRNA expression relative to the alternative alleles due to higher affinity for AP-2α and abrogation of miR-4486 binding, respectively. These variants associated with lower Plasmodium falciparum parasite prevalence and lower incidence of clinical malaria specifically among individuals carrying tapasin-dependent HLA-I allotypes, presumably by augmenting peptide loading, whereas tapasin-independent allotypes associated with relative protection, regardless of imputed TAPBP mRNA expression levels. Thus, an attenuated course of malaria may occur through enhanced breadth and/or magnitude of antigen presentation, an important consideration when evaluating vaccine efficacy.


Assuntos
Antígenos de Histocompatibilidade Classe I , Malária Falciparum , Proteínas de Membrana Transportadoras , Plasmodium falciparum , Sítios de Ligação , Variação Genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Malária Falciparum/genética , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , MicroRNAs/metabolismo , Peptídeos/imunologia , Plasmodium falciparum/imunologia , RNA Mensageiro/genética , Fator de Transcrição AP-2/metabolismo
3.
Clin Gastroenterol Hepatol ; 20(3): 602-610.e5, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33838349

RESUMO

BACKGROUND & AIMS: Pediatric functional constipation (PFC) is a common problem in children that causes distress and presents treatment challenges to health care professionals. We conducted a randomized, placebo-controlled trial (study 1) in patients with PFC (6-17 years of age) to evaluate the efficacy and safety of lubiprostone, followed by an open-label extension for those who completed the placebo-controlled phase (study 2). METHODS: Study 1 (NCT02042183) was a phase 3, multicenter, randomized, double-blind, placebo-controlled, 12-week study evaluating the efficacy and safety of lubiprostone 12 µg twice daily (BID) and 24 µg BID. Study 2 (NCT02138136) was a phase 3, long-term, open-label extension of study 1. In both studies, lubiprostone doses were based on patients' weight. Efficacy was assessed solely based on study 1, with a primary endpoint of overall spontaneous bowel movement (SBM) response (increase of ≥1 SBM/wk vs baseline and ≥3 SBMs/wk for ≥9 weeks, including 3 of the final 4 weeks). RESULTS: 606 patients were randomized to treatment (placebo: n = 202; lubiprostone: n = 404) in study 1. No statistically significant difference in overall SBM response rate was observed between the lubiprostone and placebo groups (18.5% vs 14.4%; P = .2245). Both the 12-µg BID and 24-µg BID doses of lubiprostone were well tolerated in the double-blind and extension phases, with a safety profile consistent with that seen in adult studies. CONCLUSIONS: Lubiprostone did not demonstrate statistically significant effectiveness over placebo in children and adolescents with PFC but did demonstrate a safety profile similar to that in adults. (ClinicalTrials.gov: Number: NCT02042183; Number: NCT02138136).


Assuntos
Constipação Intestinal , Defecação , Adolescente , Adulto , Criança , Constipação Intestinal/tratamento farmacológico , Método Duplo-Cego , Pessoal de Saúde , Humanos , Lubiprostona/uso terapêutico , Resultado do Tratamento
4.
Clin Infect Dis ; 73(9): e3133-e3135, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33015715

RESUMO

Prospective serial sampling of 70 patients revealed clinically relevant cycle thresholds (Ct) occurring 9, 26, and 36 days after symptom onset. Race, gender, and corticosteroids apparently did not influence RNA positivity. In a retrospective analysis of 180 patients, initial Ct did not correlate with requirements for admission or intensive care.


Assuntos
COVID-19 , SARS-CoV-2 , Hospitalização , Humanos , Estudos Prospectivos , Estudos Retrospectivos
5.
J Pediatr Gastroenterol Nutr ; 73(5): 572-578, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34387619

RESUMO

OBJECTIVES: Pediatric functional constipation (PFC) affects up to 30% of children. Current treatments often do not sustain symptomatic relief. Lubiprostone is a locally acting chloride channel activator that promotes fluid secretion into the small bowel without affecting serum electrolyte concentrations. We assessed the safety/tolerability of oral lubiprostone as treatment for PFC in a 24-week study. METHODS: This phase 3 open-label safety trial conducted from April-November 2016 at 13 US sites included patients (ages 6-17 years) diagnosed with PFC (Rome III criteria). Patients <50 and ≥50 kg received lubiprostone 12 or 24 mcg twice daily, respectively, for 24 weeks. Safety endpoints included incidence of treatment-emergent adverse events (TEAEs) and changes from baseline in clinical laboratory parameters and vital signs. RESULTS: Overall, 87 patients receiving lubiprostone, 64.3% (36/56) in the 12-mcg group and 54.8% (17/31) in the 24-mcg group, completed the study. Of 12 TEAEs leading to discontinuation, only upper abdominal pain occurred in >1 patient. TEAEs were mostly mild in intensity, with gastrointestinal disorders (diarrhea, vomiting) most frequently reported. No safety concerns were found in vital signs, abbreviated physical examinations, and laboratory tests. Subgroup analyses assessed an impact of age, sex, and race categories on TEAEs and treatment-related adverse events. Mean investigators' assessments of treatment effectiveness (scale of 0-4) for lubiprostone 12- and 24-mcg groups, respectively, were 2.8 and 2.9 at week 12, and 2.7 and 2.2 at week 24. CONCLUSIONS: Lubiprostone was well tolerated in the pediatric population. The incidence of TEAEs was comparable to that observed in previous clinical trials and in adults.


Assuntos
Alprostadil , Constipação Intestinal , Adolescente , Adulto , Criança , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/tratamento farmacológico , Diarreia , Humanos , Lubiprostona , Resultado do Tratamento , Vômito/induzido quimicamente
6.
Emerg Infect Dis ; 23(3): 430-438, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28221130

RESUMO

The genus Bartonella contains >40 species, and an increasing number of these Bartonella species are being implicated in human disease. One such pathogen is Bartonella ancashensis, which was isolated in blood samples from 2 patients living in Caraz, Peru, during a clinical trial of treatment for bartonellosis. Three B. ancashensis strains were analyzed by using whole-genome restriction mapping and high-throughput pyrosequencing. Genome-wide comparative analysis of Bartonella species showed that B. ancashensis has features seen in modern and ancient lineages of Bartonella species and is more related to B. bacilliformis. The divergence between B. ancashensis and B. bacilliformis is much greater than what is seen between known Bartonella genetic lineages. In addition, B. ancashensis contains type IV secretion system proteins, which are not present in B. bacilliformis. Whole-genome analysis indicates that B. ancashensis might represent a distinct Bartonella lineage phylogenetically related to B. bacilliformis.


Assuntos
Infecções por Bartonella/microbiologia , Bartonella/genética , Genoma Bacteriano , Adolescente , Adulto , Bartonella/classificação , Infecções por Bartonella/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Peru/epidemiologia , Filogenia , Adulto Jovem
7.
Artigo em Inglês | MEDLINE | ID: mdl-28223389

RESUMO

The emergence of a transferable colistin resistance gene (mcr-1) is of global concern. The insertion sequence ISApl1 is a key component in the mobilization of this gene, but its role remains poorly understood. Six Escherichia coli isolates were cultured from the same patient over the course of 1 month in Germany and the United States after a brief hospitalization in Bahrain for an unconnected illness. Four carried mcr-1 as determined by real-time PCR, but two were negative. Two additional mcr-1-negative E. coli isolates were collected during follow-up surveillance 9 months later. All isolates were analyzed by whole-genome sequencing (WGS). WGS revealed that the six initial isolates were composed of two distinct strains: an initial ST-617 E. coli strain harboring mcr-1 and a second, unrelated, mcr-1-negative ST-32 E. coli strain that emerged 2 weeks after hospitalization. Follow-up swabs taken 9 months later were negative for the ST-617 strain, but the mcr-1-negative ST-32 strain was still present. mcr-1 was associated with a single copy of ISApl1, located on a 64.5-kb IncI2 plasmid that shared >95% homology with other mcr-1 IncI2 plasmids. ISApl1 copy numbers ranged from 2 for the first isolate to 6 for the final isolate, but ISApl1 movement was independent of mcr-1 Some movement was accompanied by gene disruption, including the loss of genes encoding proteins involved in stress responses, arginine catabolism, and l-arabinose utilization. These data represent the first comprehensive analysis of ISApl1 movement in serial clinical isolates and reveal that, under certain conditions, ISApl1 is a highly active IS element whose movement may be detrimental to the host cell.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Elementos de DNA Transponíveis/genética , Proteínas de Escherichia coli/genética , Escherichia coli , Sequência de Bases , DNA Girase/genética , DNA Topoisomerase IV/genética , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Genoma Bacteriano/genética , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , beta-Lactamases/genética
8.
J Clin Microbiol ; 54(6): 1546-1551, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27030488

RESUMO

Carbapenem-resistant Pseudomonas aeruginosa, Acinetobacter spp., and Enterobacteriaceae pose urgent public health threats. The differential burden, relative risks, associations with antimicrobial consumption, and temporal trends of those taxa in large, geographically diverse U.S. health systems remain under reported. Electronic records of all patients in a geographically dispersed 280-hospital managed-care system from 2005 to 2014 were reviewed. Carbapenem-resistant strains were identified based on Clinical and Laboratory Standards Institute guidelines and breakpoints. A total of 360,000 potentially carbapenem-resistant strains were identified from 14.7 million cultures (80% infecting and 20% surveillance). Isolation of bacteria overseas or isolation from the bloodstream was associated with a higher relative risks of carbapenem resistance (CR; P < 0.0001). Enterobacteriaceae were isolated 11 times more frequently than P. aeruginosa and Acinetobacter spp. However, compared to Enterobacteriaceae, the CR levels were 73-fold and 210-fold higher in P. aeruginosa and Acinetobacter spp., respectively. Significant differences in the relative risk of CR between taxa, anatomic, and geographic locations persisted after adjustment for other variables, the biggest differences occurring between taxa. Overall, CR rates increased for Enterobacteriaceae (P = 0.03) and decreased for Acinetobacter spp. and P. aeruginosa (P < 0.0001). These data provide a useful baseline for resistance trending and have implications for surveillance. Infections acquired overseas and bloodstream infections are particularly important areas for continued monitoring.


Assuntos
Acinetobacter/isolamento & purificação , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Enterobacteriaceae/isolamento & purificação , Infecções por Bactérias Gram-Negativas/epidemiologia , Pseudomonas aeruginosa/isolamento & purificação , Resistência beta-Lactâmica , Acinetobacter/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Enterobacteriaceae/efeitos dos fármacos , Feminino , Geografia , Infecções por Bactérias Gram-Negativas/microbiologia , Instalações de Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Instalações Militares , Pseudomonas aeruginosa/efeitos dos fármacos , Risco , Estados Unidos , Adulto Jovem
9.
Clin Infect Dis ; 61(2): 145-54, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25824815

RESUMO

BACKGROUND: Severe Acinetobacter baumannii infections in immunocompetent patients are uncommon, and the virulence mechanisms of this organism are not fully understood. METHODS: Following an outbreak of fatal A. baumannii infections in a cohort of relatively immunocompetent patients (low comorbidity and illness severity scores), isolates were investigated with comparative genomics and in animal models. RESULTS: Two unrelated A. baumannii clades were associated with the outbreak. The clone associated with the majority of patient deaths, clade B, is evolutionarily distinct from the 3 international clonal complexes, belongs to multilocus sequence type (MLST) 10, and is most closely related to strains isolated from the Czech Republic, California, and Germany in 1994, 1997, and 2003, respectively. In 2 different murine models, clade B isolates were more virulent than comparator strains, including the highly virulent reference strain AB5075. The most virulent clade B derivative, MRSN 16897, was isolated from the patient with the lowest combined comorbidity/illness severity score. Clade B isolates possess a unique combination of putative virulence genes involved in iron metabolism, protein secretion, and glycosylation, which was leveraged to develop a rapid and specific clinical assay to detect this clade that cannot be distinguished by MLST. CONCLUSIONS: Clade B warrants continued surveillance and investigation.


Assuntos
Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/mortalidade , Acinetobacter baumannii/patogenicidade , Surtos de Doenças , Farmacorresistência Bacteriana Múltipla , Infecções por Acinetobacter/genética , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/classificação , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Adulto , Idoso de 80 Anos ou mais , Animais , California , República Tcheca , Modelos Animais de Doenças , Farmacorresistência Bacteriana Múltipla/genética , Feminino , Genômica , Alemanha , Humanos , Imunocompetência , Masculino , Camundongos , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Filogenia , Centros de Atenção Terciária/estatística & dados numéricos , Estados Unidos/epidemiologia , Virulência/genética
10.
BMC Genomics ; 16(1): 732, 2015 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-26409826

RESUMO

BACKGROUND: Genomic instability plays an important role in human cancers. We previously characterized genomic instability in esophageal squamous cell carcinomas (ESCC) in terms of loss of heterozygosity (LOH) and copy number (CN) changes in tumors. In the current study we focus on biallelic loss and its relation to expression of mRNA and miRNA in ESCC using results from 500 K SNP, mRNA, and miRNA arrays in 30 cases from a high-risk region of China. RESULTS: (i) Biallelic loss was uncommon but when it occurred it exhibited a consistent pattern: only 77 genes (<0.5%) showed biallelic loss in at least 10% of ESCC samples, but nearly all of these genes were concentrated on just four chromosomal arms (i.e., 42 genes on 3p, 14 genes on 9p, 10 genes on 5q, and seven genes on 4p). (ii) Biallelic loss was associated with lower mRNA expression: 52 of the 77 genes also had RNA expression data, and 41 (79%) showed lower expression levels in cases with biallelic loss compared to those without. (iii) The relation of biallelic loss to miRNA expression was less clear but appeared to favor higher miRNA levels: of 60 miRNA-target gene pairs, 34 pairs (57%) had higher miRNA expression with biallelic loss than without, while 26 pairs (43%) had lower miRNA expression. (iv) Finally, the effect of biallelic loss on the relation between miRNA and mRNA expression was complex. Biallelic loss was most commonly associated with a pattern of elevated miRNA and reduced mRNA (43%), but a pattern of both reduced miRNA and mRNA was also common (35%). CONCLUSION: Our results indicate that biallelic loss in ESCC is uncommon, but when it occurs it is localized to a few specific chromosome regions and is associated with reduced mRNA expression of affected genes. The effect of biallelic loss on miRNA expression and on the relation between miRNA and mRNA expressions was complex.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Estudos de Associação Genética , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Adulto , Idoso , Alelos , China , Cromossomos Humanos , Carcinoma de Células Escamosas do Esôfago , Feminino , Instabilidade Genômica , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Transcriptoma
11.
Clin Infect Dis ; 59(3): 390-7, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24795331

RESUMO

Responding to escalating antimicrobial resistance (AMR), the US Department of Defense implemented an enterprise-wide collaboration, the Antimicrobial Resistance Monitoring and Research Program, to aid in infection prevention and control. It consists of a network of epidemiologists, bioinformaticists, microbiology researchers, policy makers, hospital-based infection preventionists, and healthcare providers who collaborate to collect relevant AMR data, conduct centralized molecular characterization, and use AMR characterization feedback to implement appropriate infection prevention and control measures and influence policy. A particularly concerning type of AMR, carbapenem-resistant Enterobacteriaceae, significantly declined after the program was launched. Similarly, there have been no further reports or outbreaks of another concerning type of AMR, colistin resistance in Acinetobacter, in the Department of Defense since the program was initiated. However, bacteria containing AMR-encoding genes are increasing. To update program stakeholders and other healthcare systems facing such challenges, we describe the processes and impact of the program.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/prevenção & controle , Infecção Hospitalar/prevenção & controle , Farmacorresistência Bacteriana , Monitoramento Epidemiológico , Pesquisa , Estados Unidos , United States Department of Defense
12.
Breast Cancer Res ; 16(3): R57, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24890385

RESUMO

INTRODUCTION: Transforming growth factor-ßs (TGF-ßs) play a dual role in breast cancer, with context-dependent tumor-suppressive or pro-oncogenic effects. TGF-ß antagonists are showing promise in early-phase clinical oncology trials to neutralize the pro-oncogenic effects. However, there is currently no way to determine whether the tumor-suppressive effects of TGF-ß are still active in human breast tumors at the time of surgery and treatment, a situation that could lead to adverse therapeutic responses. METHODS: Using a breast cancer progression model that exemplifies the dual role of TGF-ß, promoter-wide chromatin immunoprecipitation and transcriptomic approaches were applied to identify a core set of TGF-ß-regulated genes that specifically reflect only the tumor-suppressor arm of the pathway. The clinical significance of this signature and the underlying biology were investigated using bioinformatic analyses in clinical breast cancer datasets, and knockdown validation approaches in tumor xenografts. RESULTS: TGF-ß-driven tumor suppression was highly dependent on Smad3, and Smad3 target genes that were specifically enriched for involvement in tumor suppression were identified. Patterns of Smad3 binding reflected the preexisting active chromatin landscape, and target genes were frequently regulated in opposite directions in vitro and in vivo, highlighting the strong contextuality of TGF-ß action. An in vivo-weighted TGF-ß/Smad3 tumor-suppressor signature was associated with good outcome in estrogen receptor-positive breast cancer cohorts. TGF-ß/Smad3 effects on cell proliferation, differentiation and ephrin signaling contributed to the observed tumor suppression. CONCLUSIONS: Tumor-suppressive effects of TGF-ß persist in some breast cancer patients at the time of surgery and affect clinical outcome. Carefully tailored in vitro/in vivo genomic approaches can identify such patients for exclusion from treatment with TGF-ß antagonists.


Assuntos
Neoplasias da Mama/genética , Proteína Smad3/genética , Fator de Crescimento Transformador beta/genética , Proteínas Supressoras de Tumor/genética , Neoplasias da Mama/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Efrinas/metabolismo , Feminino , Humanos , Regiões Promotoras Genéticas/genética , Interferência de RNA , RNA Interferente Pequeno , Receptor EphA2/metabolismo , Proteína Smad2/genética , Proteína Smad3/biossíntese , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/biossíntese , Proteínas Supressoras de Tumor/antagonistas & inibidores
13.
J Infect Dis ; 208(7): 1142-51, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23812239

RESUMO

BACKGROUND: Colistin resistance is of concern since it is increasingly needed to treat infections caused by bacteria resistant to all other antibiotics and has been associated with poorer outcomes. Longitudinal data from in vivo series are sparse. METHODS: Under a quality-improvement directive to intensify infection-control measures, extremely drug-resistant (XDR) bacteria undergo phenotypic and molecular analysis. RESULTS: Twenty-eight XDR Acinetobacter baumannii isolates were longitudinally recovered during colistin therapy. Fourteen were susceptible to colistin, and 14 were resistant to colistin. Acquisition of colistin resistance did not alter resistance to other antibiotics. Isolates had low minimum inhibitory concentrations of an investigational aminoglycoside, belonged to multi-locus sequence type 94, were indistinguishable by pulsed-field gel electrophoresis and optical mapping, and harbored a novel pmrC1A1B allele. Colistin resistance was associated with point mutations in the pmrA1 and/or pmrB genes. Additional pmrC homologs, designated eptA-1 and eptA-2, were at distant locations from the operon. Compared with colistin-susceptible isolates, colistin-resistant isolates displayed significantly enhanced expression of pmrC1A1B, eptA-1, and eptA-2; lower growth rates; and lowered fitness. Phylogenetic analysis suggested that colistin resistance emerged from a single progenitor colistin-susceptible isolate. CONCLUSIONS: We provide insights into the in vivo evolution of colistin resistance in a series of XDR A. baumannii isolates recovered during therapy of infections and emphasize the importance of antibiotic stewardship and surveillance.


Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Colistina/uso terapêutico , Farmacorresistência Bacteriana , Fatores de Transcrição/genética , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Adulto , Antibacterianos/farmacologia , Colistina/farmacologia , Genótipo , Humanos , Estudos Longitudinais , Testes de Sensibilidade Microbiana , Tipagem Molecular , Óperon , Mutação Puntual , Infecção dos Ferimentos/tratamento farmacológico
14.
J Chromatogr A ; 1724: 464908, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38669943

RESUMO

Affinity tags are frequently engineered into recombinant proteins to facilitate purification. Although this technique is powerful, removal of the tag is desired because the tag can interfere with biological activity and can potentially increase the immunogenicity of therapeutic proteins. Tag removal is complex, as it requires adding expensive protease enzymes. To overcome this limitation, split intein based affinity purification systems have been developed in which a CC-intein tag is engineered into a protein of interest for binding to a NC-intein peptide ligand fixed to a chromatographic support. Tag removal in these systems is achieved by creating an active intein-complex during protein capture, which triggers a precise self-cleavage reaction. In this work, we show applications of a new split intein system, Cytiva™ ProteinSelect™. One advantage of the new system is that the NC-intein ligand can be robustly produced and conjugated to large volumes of resin for production of gram scale proteins. SARS-CoV-2 spike protein receptor binding domain and a Bispecific T Cell Engager in this work were successfully captured on the affinity resin and scaled 10-fold. Another advantage of this system is the ability to sanitize the resin with sodium hydroxide without loosing the 10-20 g/L binding capacity. Binding studies with IL-1b and IFNAR-1 ECD showed that the resin can be regenerated and sanitized for up to 50 cycles without loosing binding capacity. Additionally, after several cycles of sanitization, binding capacity was retained for the SARS-CoV-2 spike protein receptor binding domain and a Bispecific T Cell Engager. As with other split intein systems, optimization was needed to achieve ideal expression and recovery. The N-terminal amino acid sequence of the protein of interest required engineering to enable the cleavage reaction. Additionally, ensuring the stability of the CC-intein tag was important to prevent premature cleavage or truncation. Controlling the hold time of the expression product and the prevention of protease activity prior to purification was needed. These results demonstrate the feasibility of the Cytiva™ ProteinSelect™ system to be used in academic and industrial research and development laboratories for the purification of novel proteins expressed in either bacterial or mammalian systems.


Assuntos
Cromatografia de Afinidade , Inteínas , Cromatografia de Afinidade/métodos , Humanos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/isolamento & purificação , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/isolamento & purificação , SARS-CoV-2/genética , SARS-CoV-2/química , Interleucina-1beta/metabolismo , Interleucina-1beta/genética
15.
Lancet Infect Dis ; 24(7): 687-697, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38518789

RESUMO

BACKGROUND: Variant-containing mRNA vaccines for COVID-19 to broaden protection against SARS-CoV-2 variants are recommended based on findings in adults. We report interim safety and immunogenicity of an omicron BA.1 variant-containing (mRNA-1273.214) primary vaccination series and booster dose in paediatric populations. METHODS: This open-label, two-part, non-randomised phase 3 trial enrolled participants aged 6 months to 5 years at 24 US study sites. Eligible participants were generally healthy or had stable chronic conditions, without known SARS-CoV-2 infection in the previous 90 days. Individuals who were acutely ill or febrile 1 day before or at the screening visit or those who previously received other COVID-19 vaccines (except mRNA-1273 for part 2) were excluded. In part 1, SARS-CoV-2-vaccine-naive participants received two-dose mRNA-1273.214 (25 µg; omicron BA.1 and ancestral Wuhan-Hu-1 mRNA) primary series. In part 2, participants who previously completed the two-dose mRNA-1273 (25 µg) primary series in KidCOVE (NCT04796896) received a mRNA-1273.214 (10 µg) booster dose. Primary study outcomes were safety and reactogenicity of the mRNA-1273.214 primary series (part 1) or booster dose (part 2) as well as the inferred effectiveness of mRNA-1273.214 based on immune responses against ancestral SARS-CoV-2 (D614G) and omicron BA.1 variant at 28 days post-primary series (part 1) or post-booster dose (part 2). The safety set included participants who received at least one dose of the study vaccine; the immunogenicity set included those who provided immunogenicity samples. Interim safety and immunogenicity are summarised in this analysis as of the data cutoff date (Dec 5, 2022). This trial is registered with ClinicalTrials.gov, NCT05436834. FINDINGS: Between June 21, 2022, and Dec 5, 2022, 179 participants received one or more doses of mRNA-1273.214 primary series (part 1) and 539 received a mRNA-1273.214 booster dose (part 2). The safety profile within 28 days after either dose of the mRNA-1273.214 primary series and the booster dose was consistent with that of the mRNA-1273 primary series in this age group, with no new safety concerns or vaccine-related serious adverse events observed. At 28 days after primary series dose 2 and the booster dose, both mRNA-1273.214 primary series (day 57, including all participants with or without evidence of prior SARS-CoV-2 infection at baseline) and booster (day 29, including participants without evidence of prior SARS-CoV-2 infection at baseline) elicited responses that were superior against omicron-BA.1 (geometric mean ratio part 1: 25·4 [95% CI 20·1-32·1] and part 2: 12·5 [11·0-14·3]) and non-inferior against D614G (part 1: 0·8 [0·7-1·0] and part 2: 3·1 [2·8-3·5]), compared with neutralising antibody responses induced by the mRNA-1273 primary series (in a historical comparator group). INTERPRETATION: mRNA-1273.214 was immunogenic against BA.1 and D614G in children aged 6 months to 5 years, with a comparable safety profile to mRNA-1273, when given as a two-dose primary series or a booster dose. These results are aligned with the US Centers for Disease Control and Prevention recommendations for the use of variant-containing vaccines for continued protection against the emerging variants of SARS-CoV-2. FUNDING: Moderna.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunização Secundária , Imunogenicidade da Vacina , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , COVID-19/imunologia , Masculino , Feminino , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Pré-Escolar , Lactente , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/administração & dosagem , Vacina de mRNA-1273 contra 2019-nCoV/imunologia , Anticorpos Antivirais/sangue , Estados Unidos , Anticorpos Neutralizantes/sangue , Vacinação/métodos
16.
Antimicrob Agents Chemother ; 57(5): 2413-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23478957

RESUMO

Klebsiella pneumoniae strain MRSN2404 was isolated from the chronic wound of a soldier who had been wounded in Iraq in 2006. The strain displayed very high MICs of all aminoglycosides, including arbekacin. A gene encoding a novel 16S rRNA methyltransferase, now designated RmtH, was identified. RmtH had 64% identity with RmtB1 and RmtB2. rmtH was bracketed by two copies of ISCR2, which may have played a role in its mobilization.


Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Klebsiella pneumoniae/genética , Metiltransferases/metabolismo , RNA Ribossômico 16S/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Humanos , Iraque , Isoenzimas/genética , Isoenzimas/metabolismo , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/isolamento & purificação , Masculino , Metiltransferases/genética , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Homologia de Sequência de Aminoácidos , Guerra
17.
Antimicrob Agents Chemother ; 57(9): 4584-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23817381

RESUMO

A carbapenem-resistant Acinetobacter baumannii strain was isolated from the peritoneal fluid of a patient with complicated intra-abdominal infection and evaluated at the Multidrug-resistant Organism Repository and Surveillance Network by whole-genome sequencing and real-time PCR. The isolate was sequence type 25 and susceptible to colistin and minocycline, with low MICs of tigecycline. blaNDM-1 was located on a plasmid with >99% homology to pNDM-BJ02. The isolate carried numerous other antibiotic resistance genes, including the 16S methylase gene, armA.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/isolamento & purificação , Peritonite/microbiologia , Plasmídeos , beta-Lactamases/genética , Infecções por Acinetobacter/diagnóstico , Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/genética , Idoso , Antibacterianos/farmacologia , Colistina/farmacologia , Farmacorresistência Bacteriana Múltipla , Sequenciamento de Nucleotídeos em Larga Escala , Honduras , Humanos , Masculino , Metiltransferases/genética , Metiltransferases/metabolismo , Minociclina/análogos & derivados , Minociclina/farmacologia , Peritonite/diagnóstico , Peritonite/tratamento farmacológico , Tigeciclina , beta-Lactamases/metabolismo
18.
Radiology ; 267(2): 560-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23392431

RESUMO

PURPOSE: To conduct a comprehensive analysis of radiologist-made assessments of glioblastoma (GBM) tumor size and composition by using a community-developed controlled terminology of magnetic resonance (MR) imaging visual features as they relate to genetic alterations, gene expression class, and patient survival. MATERIALS AND METHODS: Because all study patients had been previously deidentified by the Cancer Genome Atlas (TCGA), a publicly available data set that contains no linkage to patient identifiers and that is HIPAA compliant, no institutional review board approval was required. Presurgical MR images of 75 patients with GBM with genetic data in the TCGA portal were rated by three neuroradiologists for size, location, and tumor morphology by using a standardized feature set. Interrater agreements were analyzed by using the Krippendorff α statistic and intraclass correlation coefficient. Associations between survival, tumor size, and morphology were determined by using multivariate Cox regression models; associations between imaging features and genomics were studied by using the Fisher exact test. RESULTS: Interrater analysis showed significant agreement in terms of contrast material enhancement, nonenhancement, necrosis, edema, and size variables. Contrast-enhanced tumor volume and longest axis length of tumor were strongly associated with poor survival (respectively, hazard ratio: 8.84, P = .0253, and hazard ratio: 1.02, P = .00973), even after adjusting for Karnofsky performance score (P = .0208). Proneural class GBM had significantly lower levels of contrast enhancement (P = .02) than other subtypes, while mesenchymal GBM showed lower levels of nonenhanced tumor (P < .01). CONCLUSION: This analysis demonstrates a method for consistent image feature annotation capable of reproducibly characterizing brain tumors; this study shows that radiologists' estimations of macroscopic imaging features can be combined with genetic alterations and gene expression subtypes to provide deeper insight to the underlying biologic properties of GBM subsets.


Assuntos
Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Feminino , Expressão Gênica , Glioblastoma/genética , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes , Taxa de Sobrevida , Terminologia como Assunto
19.
J Clin Microbiol ; 51(6): 1942-4, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23554204

RESUMO

A carbapenem-resistant Alcaligenes faecalis strain was isolated from a surveillance swab of a service member injured in Afghanistan. The isolate was positive for bla(NDM) by real-time PCR. Species identification was reevaluated on three identification systems but was inconclusive. Genome sequencing indicated that the closest relative was Acinetobacter schindleri and that bla(NDM-1) was carried on a plasmid that shared >99% identity with one identified in an Acinetobacter lwoffii isolate. The isolate also carried a novel chromosomally encoded class D oxacillinase.


Assuntos
Acinetobacter/enzimologia , Acinetobacter/genética , beta-Lactamases/genética , Acinetobacter/isolamento & purificação , Infecções por Acinetobacter/microbiologia , Afeganistão , Cromossomos Bacterianos , DNA Bacteriano/química , DNA Bacteriano/genética , Humanos , Dados de Sequência Molecular , Plasmídeos , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
20.
Sci Transl Med ; 15(707): eadg0873, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37531416

RESUMO

Host restriction factors play key roles in innate antiviral defense, but it remains poorly understood which of them restricts HIV-1 in vivo. Here, we used single-cell transcriptomic analysis to identify host factors associated with HIV-1 control during acute infection by correlating host gene expression with viral RNA abundance within individual cells. Wide sequencing of cells from one participant with the highest plasma viral load revealed that intracellular viral RNA transcription correlates inversely with expression of the gene PTMA, which encodes prothymosin α. This association was genome-wide significant (Padjusted < 0.05) and was validated in 28 additional participants from Thailand and the Americas with HIV-1 CRF01_AE and subtype B infections, respectively. Overexpression of prothymosin α in vitro confirmed that this cellular factor inhibits HIV-1 transcription and infectious virus production. Our results identify prothymosin α as a host factor that restricts HIV-1 infection in vivo, which has implications for viral transmission and cure strategies.


Assuntos
Infecções por HIV , HIV-1 , Humanos , HIV-1/genética , Transcriptoma/genética , Infecções por HIV/genética , RNA Viral
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