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1.
Lancet Reg Health West Pac ; 40: 100895, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37691885

RESUMO

Background: Previous studies demonstrated that induction chemotherapy (IC) followed by de-escalated chemoradiotherapy adapted to tumor response was effective in treating childhood nasopharyngeal carcinoma (NPC), but the toxicity profile of this treatment strategy, and whether childhood patients with advanced stages can obtain enough benefits from it requires further investigation. Methods: We conducted a single-center phase II trial (NCT03020329). All participants received 3 cycles of paclitaxel liposome, cisplatin and 5-fluorouracil (TPF)-based IC. Patients who showed complete or partial response received de-escalated radiotherapy of 60 Gy with 3 cycles of concurrent cisplatin, and those who showed stable or progressive disease received standard-dose radiotherapy of 70 Gy with concurrent cisplatin. The primary endpoint was the complete response (CR) rate at the end of concurrent chemoradiotherapy (CCRT). Findings: From November 2016 to March 2021, 44 patients were recruited in the cohort. The CR rate was 80% (35/44, 95% CI, 65-90) of the whole cohort. All patients achieved CR 3 months after CCRT. By the last follow-up, the 3-year progression-free survival and overall survival were 91% (95% CI, 82-99) and 100% respectively. Dry mouth was the most common late toxicity, with an incidence of 41% (18/44), followed by skin fibrosis and hearing impairment. No patient suffered from severe late toxicity and growth retardation. Interpretation: Our results proved the efficacy and safety of TPF regimen followed by de-escalated radiotherapy with concurrent cisplatin in treating stage IVa-b childhood NPC patients. Funding: A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.

2.
Vaccine ; 41(1): 109-118, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36404171

RESUMO

BACKGROUND: Data from previous studies of the MVC-COV1901 vaccine, a subunit vaccine against SARS-CoV-2 based on the stable prefusion spike protein (S-2P) adjuvanted with CpG 1018 adjuvant and aluminum hydroxide, suggest that the vaccine is generally safe and elicits a good immune response in healthy adults and adolescents. By comparing with AZD1222, this study adds to the findings from previous trials and further evaluates the breadth of protection offered by MVC-COV1901. METHODS: In this phase 3, parallel group, randomized, double-blind, active-controlled trial conducted in 2 sites in Paraguay, we assigned adults aged 18-91 years in a 1:1 ratio to receive intramuscular doses of MVC-COV1901 or AZD1222 administered as scheduled in the clinical trial. Serum samples were collected on the day of vaccination and 14 days after the second dose. Primary and secondary safety and immunogenicity endpoints were assessed. In addition, other outcomes investigated were cross-reactive immunity against the Omicron strain and the induction of IgG subclasses. RESULTS: A total of 1,030 participants underwent randomization. Safety data was derived from this set while primary immunogenicity data involved a per-protocol immunogenicity (PPI) subset including 225 participants. Among the participants, 58% are seropositive at baseline. When compared against AZD1222, MVC-COV1901 exhibited superiority in terms of neutralizing antibody titers and non-inferiority in terms of seroconversion rates. Reactogenicity was generally mild and no serious adverse event was attributable to MVC-COV1901. Both vaccines have a Th1-biased response predominated by the production of IgG1 and IgG3 subclasses. Omicron-neutralizing titers were 44.5 times lower compared to wildtype-neutralizing titers among seronegative individuals at baseline. This fold-reduction was 3.0 times among the seropositive. CONCLUSION: Safety and immunogenicity data of MVC-COV1901 from the study in Paraguay confirm previous results. The previous infection coupled with vaccination of this vaccine may offer protection against the Omicron strain though its durability is still unknown.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Adulto , Adolescente , Humanos , Vacinas contra COVID-19/efeitos adversos , SARS-CoV-2 , ChAdOx1 nCoV-19 , COVID-19/prevenção & controle , Paraguai , Método Duplo-Cego , Imunoglobulina G , Adjuvantes Imunológicos , Vacinas de Subunidades Antigênicas , Imunogenicidade da Vacina , Anticorpos Antivirais , Anticorpos Neutralizantes
3.
Rev. bras. entomol ; Rev. bras. entomol;56(2): 259-262, Apr.-June 2012. graf
Artigo em Inglês | LILACS | ID: lil-640840

RESUMO

Effects of female diet and age on offspring sex ratio of the solitary parasitoid Pachycrepoideus vindemmiae (Rondani) (Hymenoptera, Pteromalidae). Theories predict that females of parasitoid wasps would adjust the offspring sex ratio to environmental conditions in the oviposition patch, but the diet and age of females would also affect the sex ratio adjustment. Our focus was to test the effects of female diet and age on offspring sex ratio of the solitary parasitoid wasp, Pachycrepoideus vindemmiae (Rondani, 1875). Our results showed that females fed with honey had significantly less female biased offspring sex ratio than those fed only with water. Offspring sex ratio (male percentage) decreased with female age or female longevity at the beginning of oviposition but increased at the end. There should be a sperm limitation in P. vindemmiae females at the end of oviposition, and a higher frequency of unfertilized eggs were laid then. Females also laid more unfertilized eggs at the beginning of oviposition, which would be necessary to insure the mating among offspring. Male offspring developed faster and emerged earlier, which would also reduce the risk of virginity in offspring with female-biased sex ratio.


Efeitos da dieta e idade da fêmea em relação à prole e à razão sexual do parasitoide solitário Pachycrepoideus vindemmiae (Rondani) (Hymenoptera, Pteromalidae). As teorias predizem que as fêmeas parasitoides de vespas ajustam a relação razão sexual dos descendentes, de acordo com condições ambientais, em cada oviposição. Entretanto, a dieta e idade das fêmeas também podem afetar o ajuste da razão sexual. Nosso foco foi testar os efeitos da dieta e idade da fêmeas em relação a razão sexual da prole da vespa parasitoide Pachycrepoideus vindemmiae (Rondani, 1875). Nossos resultados mostraram que as fêmeas alimentadas com mel apresentaram uma razão sexual significativa menor de fêmeas, do que aquelas alimentadas apenas com água. A razão sexual (percentagem dos machos) diminuiu com a idade ou longevidade das fêmeas no início da oviposição, mas com aumento no final. Deve haver uma limitação de esperma nas fêmeas de P. vindemmiae no final da oviposição e uma maior frequência de posturas de ovos infertilizados. As fêmeas também fazem posturas de um número maior de ovos infertilizados no início da oviposição, que seria necessário para assegurar o acasalamento entre os descendentes. A prole masculina desenvolverá mais rapidamente e emergirá mais cedo, o que também reduziria o risco de virgindade da prole, com a tendenciosa proporção de razão sexual maior das fêmeas.

4.
J Microbiol Immunol Infect ; 41(6): 507-12, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19255695

RESUMO

BACKGROUND AND PURPOSE: Previous studies have indicated that Salmonella enterica serotype Panama causes systemic infections in humans. The present study was undertaken to gain more understanding of the molecular epidemiology and antimicrobial resistance of Salmonella Panama. METHODS: Antimicrobial susceptibility testing and molecular typing were performed on 9 clinical isolates by pulsed-field gel electrophoresis (PFGE). The presence of resistance genes, Salmonella genomic island 1 (SGI1), and integrons was examined by polymerase chain reaction. Plasmid profiles of these isolates were also determined. RESULTS: Molecular typing showed 3 predominant PFGE types with 6 subtypes among these isolates. High rates of antimicrobial resistance to trimethoprim-sulfamethoxazole (66.7%), tetracycline (66.7%), chloramphenicol (66.7%), ampicillin (55.6%), streptomycin (55.6%), kanamycin (55.6%), and gentamicin (44.4%) were found. All 9 isolates were susceptible to ceftriaxone, cefixime, imipenem, amikacin, and ciprofloxacin. Isolates with PFGE type P1 and subtype P1-1 contained a class 1 integron and resistance genes sulI and str (p=0.048). Plasmids of 3 to 20 kb were found in all isolates belonging to PFGE type P1, subtypes P1-1 and P1-2, which were associated with multidrug resistance (p=0.012) and the resistant gene bla(TEM) (p=0.048). There was no SGI1 found in these 9 isolates. CONCLUSIONS: In view of the high rates of drug resistance to the antimicrobial agents tested, extended-spectrum cephalosporins and fluoroquinolones seem to be a better choice for treatment of systemic infection caused by Salmonella Panama. There is a major clone (P1 and its subtypes) among the Salmonella Panama isolates. Multidrug resistance was conferred by integrons or plasmids, rather than SGI1.


Assuntos
Farmacorresistência Bacteriana/genética , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , Anti-Infecciosos/farmacologia , Interpretação Estatística de Dados , Farmacorresistência Bacteriana Múltipla/genética , Eletroforese em Gel de Campo Pulsado , Ilhas Genômicas/genética , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Plasmídeos/genética , Reação em Cadeia da Polimerase , Salmonella enterica/isolamento & purificação , Taiwan
5.
J Biol Chem ; 280(31): 28316-23, 2005 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-15937339

RESUMO

Translational control directed by the eukaryotic translation initiation factor 2 alpha-subunit (eIF2alpha) kinase GCN2 is important for coordinating gene expression programs in response to nutritional deprivation. The GCN2 stress response, conserved from yeast to mammals, is critical for resistance to nutritional deficiencies and for the control of feeding behaviors in rodents. The mouse protein IMPACT has sequence similarities to the yeast YIH1 protein, an inhibitor of GCN2. YIH1 competes with GCN2 for binding to a positive regulator, GCN1. Here, we present evidence that IMPACT is the functional counterpart of YIH1. Overexpression of IMPACT in yeast lowered both basal and amino acid starvation-induced levels of phosphorylated eIF2alpha, as described for YIH1 (31). Overexpression of IMPACT in mouse embryonic fibroblasts inhibited phosphorylation of eIF2alpha by GCN2 under leucine starvation conditions, abolishing expression of its downstream target genes, ATF4 (CREB-2) and CHOP (GADD153). IMPACT bound to the minimal yeast GCN1 segment required for interaction with yeast GCN2 and YIH1 and to native mouse GCN1. At the protein level, IMPACT was detected mainly in the brain. IMPACT was found to be abundant in the majority of hypothalamic neurons. Scattered neurons expressing this protein at higher levels were detected in other regions such as the hippocampus and piriform cortex. The abundance of IMPACT correlated inversely with phosphorylated eIF2alpha levels in different brain areas. These results suggest that IMPACT ensures constant high levels of translation and low levels of ATF4 and CHOP in specific neuronal cells under amino acid starvation conditions.


Assuntos
Encéfalo/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Proteínas Quinases/metabolismo , Proteínas/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Primers do DNA , DNA Complementar , Proteínas de Ligação a DNA/genética , Deleção de Genes , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Proteínas dos Microfilamentos/metabolismo , Dados de Sequência Molecular , Fatores de Alongamento de Peptídeos , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases , Proteínas/metabolismo , Proteínas de Ligação a RNA , Proteínas de Saccharomyces cerevisiae/genética , Transativadores
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