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1.
J Law Med Ethics ; 50(4): 807-817, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36883404

RESUMO

Several countries maintain universal health coverage, which implies responsibility to organize delivery formats of healthcare services and products for citizens. In Brazil, the health system has a principle of universal access for more than 30 years, but many deficiencies remain and the country observes a day practice for those seeking judicial decisions to determine provision of healthcare.


Assuntos
Medicina Baseada em Evidências , Política de Saúde , Humanos , Conhecimento , Instalações de Saúde , Cobertura Universal do Seguro de Saúde
2.
Cell Tissue Res ; 368(3): 579-590, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28285353

RESUMO

Termites are the major decomposers of lignocellulosic biomass on Earth and are commonly considered as biological reactor models for lignocellulose degradation. Despite their biotechnological potential, few studies have focused on the morphophysiological aspects of the termite digestive system. We therefore analyze the morphology, ultrastructure and gut luminal pH of the digestive system in workers of the litter-feeding termite Cornitermes cumulans (Blattodea: Termitidae). Their digestive system is composed of salivary glands and an alimentary canal with a pH ranging from neutral to alkaline. The salivary glands have an acinar structure and present cells with secretory characteristics. The alimentary canal is differentiated into the foregut, midgut, mixed segment and hindgut, which comprises the ileum (p1), enteric valve (p2), paunch (p3), colon (p4) and rectum (p5) segments. The foregut has a well-developed chewing system. The midgut possesses a tubular peritrophic membrane and two cell types: digestive cells with secretory and absorptive features and several regenerative cells in mitosis, both cell types being organized into regenerative crypts. The mixed segment exhibits cells rich in glycogen granules. Hindgut p1, p4 and p5 segments have flattened cells with a few apical invaginations related to mitochondria and a thick cuticular lining. Conversely, the hindgut p3 segment contains large cuboid cells with extensive apical invaginations associated with numerous mitochondria. These new insights into the morphophysiology of the digestive system of C. cumulans reveal that it mobilizes lignocellulose components as a nutritional source by means of a highly compartmentalized organization with specialized segments and complex microenvironments.


Assuntos
Isópteros/anatomia & histologia , Animais , Sistema Digestório/anatomia & histologia , Comportamento Alimentar , Concentração de Íons de Hidrogênio , Isópteros/fisiologia , Isópteros/ultraestrutura , Glândulas Salivares/anatomia & histologia , Glândulas Salivares/ultraestrutura
3.
J Insect Physiol ; 52(5): 468-72, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16580013

RESUMO

The objective of this work was to study the pattern of salivation of triatomines during feeding in mouse skin. Rhodnius prolixus was fed with a solution of the dye acridine orange or fluorescein. The saliva was efficiently labelled with acridine orange, probably due to the difference in pH between the salivary gland (6.0) and the hemolymph (6.5-7.0). This procedure was not effective at labelling the saliva of Triatoma infestans, however, fluorescent labelling of R. prolixus saliva allowed us to demonstrate that salivation occurs during entire feeding process. The saliva is released soon after the bite. In the probing phase, saliva is pumped continuously in the host skin, including around the blood vessels. During the engorgement phase, saliva is observed in a bolus within the blood vessel and some of it is sucked up by the insect, together with blood. The frequency of saliva emission inside the vessels was low (0.51+/-0.18 Hz). The saliva deposition in the microcirculation is continuous and modulated by the frequency of the cibarial pump because, when functioning at high frequency, cibarial pump sucks almost all saliva to the insect gut. This mechanism would determine the quantity of saliva deposited in the microcirculation as necessary, and consequently minimizing the host's immune response to salivary antigens.


Assuntos
Rhodnius/fisiologia , Salivação/fisiologia , Pele/parasitologia , Animais , Corantes Fluorescentes , Hemolinfa/metabolismo , Concentração de Íons de Hidrogênio , Camundongos , Saliva/metabolismo , Glândulas Salivares/fisiologia
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