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1.
EBioMedicine ; 86: 104378, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36462405

RESUMO

BACKGROUND: Miltefosine treatment failure in visceral leishmaniasis in Brazil has been associated with deletion of the miltefosine susceptibility locus (MSL) in Leishmania infantum. The MSL comprises four genes, 3'-nucleotidase/nucleases (NUC1 and NUC2); helicase-like protein (HLP); and 3,2-trans-enoyl-CoA isomerase (TEI). METHODS: In this study CRISPR-Cas9 was used to either epitope tag or delete NUC1, NUC2, HLP and TEI, to investigate their role in miltefosine resistance mechanisms. Additionally, miltefosine transporter genes and miltefosine-mediated reactive oxygen species homeostasis were assessed in 26 L. infantum clinical isolates. A comparative lipidomic analysis was also performed to investigate the molecular basis of miltefosine resistance. FINDINGS: Deletion of both NUC1, NUC2 from the MSL was associated with a significant decrease in miltefosine susceptibility, which was restored after re-expression. Metabolomic analysis of parasites lacking the MSL or NUC1 and NUC2 identified an increase in the parasite lipid content, including ergosterol; these lipids may contribute to miltefosine resistance by binding the drug in the membrane. Parasites lacking the MSL are more resistant to lipid metabolism perturbation caused by miltefosine and NUC1 and NUC2 are involved in this pathway. Additionally, L. infantum parasites lacking the MSL isolated from patients who relapsed after miltefosine treatment were found to modulate nitric oxide accumulation in host macrophages. INTERPRETATION: Altogether, these data indicate that multifactorial mechanisms are involved in natural resistance to miltefosine in L. infantum and that the absence of the 3'nucleotidase/nuclease genes NUC1 and NUC2 contributes to the phenotype. FUNDING: MRC GCRF and FAPES.


Assuntos
Antiprotozoários , Leishmania infantum , Leishmania infantum/genética , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Fosforilcolina/farmacologia , Fosforilcolina/uso terapêutico , Nucleotidases/metabolismo
2.
Entropy (Basel) ; 24(11)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36421526

RESUMO

Thermoeconomics connects thermodynamic and economic concepts in order to provide information not available in conventional energy and economic analysis. Most thermoeconomicists agree that exergy is the most appropriate thermodynamic magnitude to associate with cost. In some applications, exergy disaggregation is required. Despite the improvement in result accuracy, the modeling complexity increases. In recent years, different exergy disaggregation approaches have been proposed, mostly to deal with dissipative components and residues, despite all of them also increasing the complexity of thermoeconomics. This study aims to present a new thermoeconomic approach based on exergy disaggregation, which is able to isolate dissipative components with less modeling complexity. This approach, called the A&F Model, splits the physical exergy into two terms, namely, Helmholtz energy and flow work. These terms were evaluated from a thermoeconomic point of view, through a cost allocation in an ideal Carnot cycle, and they were also applied and compared with the UFS Model, through a cost allocation analysis, in a case study with an organic Rankine cycle-powered vapor compression refrigeration system. The complexity and computational effort reduction in the A&F are significantly less than in the UFS Model. This alternative approach yields consistent results.

3.
Braz J Vet Med ; 44: e002022, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36066911

RESUMO

Rabies is a highly lethal disease and is considered one of the most important zoonoses worldwide. In Brazil, the rabies cycle in domestic animals is under control. However, there is feedback from the wildlife cycle as many bats are present in the cities and rural areas of the country. This paper reports a case of a dog receiving veterinary assistance that presented with misbehavior and other unusual signs. After clinical evaluation by two veterinarians and a period of hospitalization to perform tests and treatment, the dog died, and the Municipal Health Department was contacted due to the suspicion of rabies. After laboratory testing and sample analysis, the diagnosis of rabies was confirmed. This case demonstrates the importance of veterinarians' qualifications in performing clinical and laboratory diagnoses, such as their knowledge concerning surveillance measures and preventive steps before and after exposure. Reinforcing the significance of maintaining vaccination coverage for rabies and promoting public and private vaccination campaigns in areas that lack vaccination campaigns are useful.


A Raiva é uma doença de elevada letalidade e é considerada uma das mais importantes zoonoses do planeta. Seu ciclo urbano está praticamente controlado no Brasil, porém, é constantemente retroalimentado pelo ciclo silvestre devido à presença de morcegos tanto nas áreas rurais como urbanas. Este trabalho relata o caso de um cão que foi levado para atendimento veterinário apresentando comportamento e outros sinais incomuns. Após a avaliação de dois profissionais veterinários e uma internação para exames e tratamento, o animal foi a óbito e o serviço municipal de saúde foi acionado devido à suspeita de Raiva. Após os devidos exames laboratoriais, a Raiva foi confirmada nas amostras analisadas. Este caso demostrou a importância não só da capacitação dos profissionais veterinários para suspeitar, realizar o diagnóstico clínico e laboratorial da Raiva como o conhecimento acerca das medidas de vigilância, prevenção e controle e os esquemas de profilaxia da raiva humana pré e pós exposição. Ressalta-se ainda a importância da manutenção da cobertura vacinal contra a Raiva, seja ela realizada por campanhas públicas de vacinação, seja por iniciativa dos tutores onde as campanhas não mais ocorrem.

4.
PLoS One ; 16(10): e0257922, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34618860

RESUMO

Exporting is a central growth strategy for most firms and managers with international experience are instrumental for export decisions. We suggest that such managers can be hired from Multinational Corporations (MNCs). We integrate theory from strategic human capital research into models explaining export decisions. We theorize that hiring managers from MNCs increases the odds of domestic firms to start exporting and this effect depends on the similarities between hiring firms and MNCs. We hypothesize that young firms will benefit comparatively less from hiring MNC managers. In contrast, firms with internationally diverse workforces and with high degrees of hierarchical specialization will benefit the most from hiring MNC managers. We test and support these hypotheses for 474,926 domestic firms in Sweden, which we observe between 2007 and 2015.


Assuntos
Tomada de Decisões , Processamento Eletrônico de Dados/tendências , Emprego/normas , Seleção de Pessoal/normas , Emprego/psicologia , Entropia , Feminino , Humanos , Masculino , Suécia
5.
Heliyon ; 5(10): e02720, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31687527

RESUMO

Early diagnosis of leptospirosis may aid in a favorable prognosis in infected animals, but there are few reports of clinical and hematochemical changes in the ovine species, nor whether the breed exerts any influence on the response to infection. Thus, the objective of the present study was to evaluate the clinical, biochemical and hematological alterations in Santa Inês and crossbred ewes challenged with Leptospira interrogans serogroup Pomona serovar Kennewicki. Twenty-four sheep were used in this experiment, 12 crossbred (group A) and 12 Santa Inês (group B). In each group, sheep were conjunctivally and intraperitoneally challenged. During 60 days post-infection the ewes were evaluated for the presentation of clinical signs and the blood was collected for hemogram and serum biochemistry. Concentration of urea and creatinine; serum aspartate aminotransferase activity (AST); gamma-glutamyltransferase (GGT); total protein and albumin; total bilirubin, direct and indirect were analyzed. The urine of these sheep was collected for urinalysis. Only two Santa Inês sheep showed blood in the urine. Clinical signs implicated in Leptospira sp. infection were not identified. Some sheep had anemia, especially crossbred. However, anemia may be attributed to the more effective cellular response that has been identified in crossbred animals. Only one animal presented leukocytosis with neutrophilia, while 11 presented atypical leukopenia, especially those of the Santa Inês breed. There was a decrease in total protein and albumin, as well as the increase in gammaglutamyltranspeptidase (GGT), especially in Santa Inês sheep. The level of aspartate aminotransferase (AST) remained within the normal range for the species. A significant increase (p < 0.05) in conjugated bilirubin levels in challenged animals was detected. Only one sheep intraperitoneally challenged presented a high level of urea in the blood, but the creatinine level remained within the normal range. The intraperitoneal route was responsible for more significant changes (p < 0.05) in the hemogram and biochemistry when compared to the conjunctival route. The results indicate that crossbred sheep have a more efficient cellular response than Santa Inês sheep, which may confer a greater resistance to infection. Clinical signs are not good parameters to follow the development of leptospirosis in crossbred and Santa Inês breed. Hematological and biochemical analyzes were useful in the detection of anemia and possible liver changes caused by leptospirosis. The intraperitoneal route was able to cause more conclusive alterations of the analyzed parameters, however, it is possible that the alterations caused by the conjunctival route reproduce in a more faithful way what happens in a natural situation of infection.

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