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71.
72.
M F Lima e Costa R S Rocha M L Leite R G Carneiro D Colley G Gazzinelli N Katz 《Revista do Instituto de Medicina Tropical de S?o Paulo》1991,33(1):58-63
Associations between socio-demographic factors, water contact patterns and Schistosoma mansoni infection were investigated in 506 individuals (87% of inhabitants over 1 year of age) in an endemic area in Brazil (Divino), aiming at determining priorities for public health measures to prevent the infection. Those who eliminated S. mansoni eggs (n = 198) were compared to those without eggs in the stools (n = 308). The following explanatory variables were considered: age, sex, color, previous treatment with schistosomicide, place of birth, quality of the houses, water supply for the household, distance from houses to stream, and frequency and reasons for water contact. Factors found to be independently associated with the infection were age (10-19 and > or = 20 yrs old), and water contact for agricultural activities, fishing, and swimming or bathing (Adjusted relative odds = 5.0, 2.4, 3.2, 2.1 and 2.0, respectively). This suggests the need for public health measures to prevent the infection, emphasizing water contact for leisure and agricultural activities in this endemic area. 相似文献
73.
Hemostatic plug (HP) formation was investigated in the ear bleeding time incision in normal and von Willebrand pigs. HP volume was calculated by integrating the areas of serial sections. In normal pigs (n = 11), platelets immediately formed a layer on the surface of the cut channel. Platelet aggregates formed at the ends of transected vessels and gradually enlarged. Finally, all transected vessels were occluded by HP and bleeding stopped. In contrast, large HPs were formed in the incision in von Willebrand's disease (vWD) pigs (n = 4); these HPs did not cover the ends of the transected vessels, which continued to bleed, allowing the formation of large hemostatically ineffective platelet aggregates in the incision. Canals traversed these HPs, and bleeding from the open vessels may have continued through them. After infusion of cryoprecipitate into a vWD pig, the bleeding time shortened, and the morphological findings of the HPs were similar to those of normal pigs. In normal pigs (n = 3) infused with an anti- Willebrand factor monoclonal antibody, which prolonged the bleeding time, a large HP formed in the incision, similar to that observed in the vWD pig. The volume of the normal and vWD HPs increased with time. These in vivo findings suggest that Willebrand factor is involved in the localization of the HP to the damaged vessel and may also play a role in platelet-platelet interaction. A computerized morphometric technique was used for measuring the volume of the hemostatic plugs and the distance of sequential points on the perimeter of the HP from the center of selected bleeding vessels. 相似文献
74.
Clinical observations in patients with X-linked hypophosphataemic rickets, that bone changes can be corrected during puberty, suggest that androgen can participate actively in the process of bone mineralization. In the present study we investigated the role of testosterone on the bone mineralization of male rats placed on a low phosphorus and vitamin D diet and kept in complete darkness after weaning. After 15 days the animals presented hypophosphataemia, rickets and osteomalacia, as assessed by histomorphometry of the tibia and seventh caudal vertebra calcification fronts respectively. Testosterone propionate administration for five days, while the animals were kept on the same rachitogenic diet, induced an improvement in the bone mineralization process of the hypophosphataemic rat independently of serum phosphate levels. Testosterone-treated rats were cured of rickets but not of osteomalacia, despite the reduction in osteoid seam area. 相似文献
75.
E. C. Santos H. S. Martinho K. Annes R. F. Leite M. P. Milazzotto 《Biomedical optics express》2015,6(8):2830-2839
Morphological assessments are used to select embryos with the highest implantation potential, however it is still very limited. The development of new technologies, such as Raman spectroscopy have improved quantitative and qualitative analysis, and consequently led to a better characterization of embryos and improvements on the prediction of their potential. Therefore, we propose a method based on the conventional in vitro culture system of bovine embryos, and the subsequent analysis of the culture media drops by Raman spectroscopy. Our results obtained by PCA analysis clearly showed a separation of the spectral profiles from culture media drops with and without embryos.OCIS codes: (170.0170) Medical optics and biotechnology, (170.5660) Raman spectroscopy, (170.1420) Biology 相似文献
76.
Gabriella Freitas Ferreira Julliana Ribeiro Alves Santos Marliete Carvalho da Costa Rodrigo Assun??o de Holanda ?ngelo Márcio Leite Denadai Gustavo José Cota de Freitas áquila Rodrigues Costa Santos Priscila Batista Tavares Tatiane Alves Paix?o Daniel Assis Santos 《Antimicrobial agents and chemotherapy》2015,59(8):4600-4609
Cryptococcus gattii is the main etiological agent of cryptococcosis in immunocompetent individuals. The triazole drug itraconazole is one of the antifungals used to treat patients with cryptococcosis. Heteroresistance is an adaptive mechanism to counteract the stress of increasing drug concentrations, and it can enhance the ability of a microorganism to survive under antifungal pressure. In this study, we evaluated the ability of 11 C. gattii strains to develop itraconazole heteroresistance. Heteroresistant clones were analyzed for drug susceptibility, alterations in cell diameter, capsule properties, and virulence in a murine model. Heteroresistance to itraconazole was intrinsic in all of the strains analyzed, reduced both the capsule size and the cell diameter, induced molecular heterogeneity at the chromosomal level, changed the negatively charged cells, reduced ergosterol content, and improved the antioxidant system. A positive correlation between surface/volume ratio of original cells and the level of heteroresistance to itraconazole (LHI) was observed in addition to a negative correlation between capsule size of heteroresistant clones and LHI. Moreover, heteroresistance to itraconazole increased the engulfment of C. gattii by macrophages and augmented fungal proliferation inside these cells, which probably accounted for the reduced survival of the mice infected with the heteroresistant clones and the higher fungal burden in lungs and brain. Our results indicate that heteroresistance to itraconazole is intrinsic and increases the virulence of C. gattii. This phenomenon may represent an additional mechanism that contributes to relapses of cryptococcosis in patients during itraconazole therapy. 相似文献
77.
78.
Luciana Ribeiro Serafim Jéssica Paôla Gonçalves da Silva Nívia Carolina Nogueira de Paiva Hudson Andrade dos Santos Maria da Gloria Quintão Silva Cláudia Martins Carneiro Sílvia Regina Costa Dias Élida Mara Leite Rabelo 《Parasitology research》2014,113(12):4611-4621
This study compared the course of Ancylostoma ceylanicum infection in hamsters infected with different inocula and the consequences for the host and helminth populations. The average of adult worms recovered, according to the number of third stage larva used, were 28.0, 24.8, 24.6, and 24.8 % to inocula size of 25 L3, 75 L3, 125 L3, and 250 L3, respectively. The size of the inoculum did not affect the establishment, survival, or fecundity of adult helminths. Reductions in the red blood cell and hemoglobin levels in the infected group were inversely proportional to the number of white blood cells. Moreover, differential cell counting revealed a positive correlation between the worm load and leucocyte numbers. The humoral response against excretion-secretion antigens was more robust and sensitive compared with the response against crude extract, with no direct linear correlation with the number of worms. The effect of the population density was more evident in females. 相似文献
79.
Madelon Novato Ribeiro Maria Inês Fernandes Pimentel Armando de Oliveira Schubach Raquel de Vasconcellos Carvalh?es de Oliveira José Liporage Teixeira Madson Pedro da Silva Leite Monique Fonseca Ginelza Peres Lima dos Santos Mariza Matos Salgueiro Erica de Camargo Ferreira e Vasconcellos Marcelo Rosandiski Lyra Mauricio Naoto Saheki Claudia Maria Valete-Rosalino 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(4):291-296
The favorable outcome of the treatment of a disease is influenced by the
adherence to therapy. Our objective was to assess factors associated with adherence
to treatment of patients included in a clinical trial of equivalence between the
standard and alternative treatment schemes with meglumine antimoniate (MA) in the
treatment of cutaneous leishmaniasis (CL), in the state of Rio de Janeiro. Between
2008 and 2011, 57 patients with CL were interviewed using a questionnaire to collect
socioeconomic data. The following methods were used for adherence monitoring:
counting of vial surplus, monitoring card, Morisky test and modified Morisky test
(without the question regarding the schedule); we observed 82.1% (vial return), 86.0%
(monitoring card), 66.7% (Morisky test) and 86.0% (modified Morisky test) adherence.
There was a strong correlation between the method of vial counting and the monitoring
card and modified Morisky test. A significant association was observed between
greater adherence to treatment and low dose of MA, as well as with a lower number of
people sleeping in the same room. We recommend the use of the modified Morisky test
to assess adherence to treatment of CL with MA, because it is a simple method and
with a good performance, when compared to other methods. 相似文献
80.
Angelos Hatzakis Jeffrey V. Lazarus Evangelos Cholongitas Ricardo Baptista‐Leite Charles Boucher Cristian‐Silviu Busoi Sylvie Deuffic‐Burban Jagpreet Chhatwal Gamal Esmat Sharon Hutchinson Minerva‐Melpomeni Malliori Mojca Maticic Antons Mozalevskis Francesco Negro George A. Papandreou George V. Papatheodoridis Markus Peck‐Radosavljevic Homie Razavi Tatjana Reic Eberhard Schatz Nurdan Tozun Zobair Younossi Michael P. Manns 《Liver international》2020,40(2):260-270
The majority of people infected with chronic hepatitis C virus (HCV) in the European Union (EU) remain undiagnosed and untreated. During recent years, immigration to EU has further increased HCV prevalence. It has been estimated that, out of the 4.2 million adults affected by HCV infection in the 31 EU/ European Economic Area (EEA) countries, as many as 580 000 are migrants. Additionally, HCV is highly prevalent and under addressed in Eastern Europe. In 2013, the introduction of highly effective treatments for HCV with direct‐acting antivirals created an unprecedented opportunity to cure almost all patients, reduce HCV transmission and eliminate the disease. However, in many settings, HCV elimination poses a serious challenge for countries’ health spending. On 6 June 2018, the Hepatitis B and C Public Policy Association held the 2nd EU HCV Policy summit. It was emphasized that key stakeholders should work collaboratively since only a few countries in the EU are on track to achieve HCV elimination by 2030. In particular, more effort is needed for universal screening. The micro‐elimination approach in specific populations is less complex and less costly than country‐wide elimination programmes and is an important first step in many settings. Preliminary data suggest that implementation of the World Health Organization (WHO) Global Health Sector Strategy on Viral Hepatitis can be cost saving. However, innovative financing mechanisms are needed to raise funds upfront for scaling up screening, treatment and harm reduction interventions that can lead to HCV elimination by 2030, the stated goal of the WHO. 相似文献