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1.
J Appl Crystallogr ; 56(Pt 4): 1002-1014, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37555227

RESUMEN

Human hair is a biopolymer constituted mainly of keratin intermediate filaments, lipids, pigments and water. Cosmetic treatments usually interact with the hair at the molecular level, inducing changes in its components and modifying the physicochemical and mechanical properties of the fibers. Here, the effect of acid straightening on the morphology and ultrastructure of Caucasian hair was investigated by a group of complementary experimental methods: wide-, small- and ultra-small-angle X-ray scattering; high-resolution 3D X-ray microscopy; quasi-elastic neutron scattering and inelastic neutron scattering; thermogravimetry-mass spectrometry; and differential scanning calorimetry (DSC). X-ray diffraction patterns showed that acid straightening associated with a flat iron (∼180°C) changed the cortex of the fiber, shown by denaturation of the intermediate filaments (measured by DSC). The increase in the spacing of the lipid layers and the observation of the dehydration behavior of the fiber provided indications that water may be confined between these layers, while neutron spectroscopy showed alterations in the vibration mode of the CH2 groups of the lipids and an increase of the proton (H+) mobility in the hair structure. The latter may be associated with the extremely low pH of the formulation (pH ≃ 1). Additionally, this investigation showed that bleached hair (one-time bleached) is more damaged by the action of acid straightening than virgin hair, which was shown by a threefold increase in the percentage of total porosity of the tresses. The obtained results demonstrate that the investigation approach proposed here can provide very important thermodynamic and structural information on induced changes of hair structure, and certainly can be applied for the evaluation of the action mode and efficiency of cosmetic treatments.

3.
Braz. j. morphol. sci ; 30(2): 82-85, 2013. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-699334

RESUMEN

The kidney is a retroperitoneal organ that weight from 125 to 170 g in the adult men and 115to 155 g in adult women. Irrigation kidney is characterized by the presence of large anatomical variability thatmay be influenced by ethnic and to a lesser extent by gender. Among the variations, there may be the presenceof an accessory renal artery that is projected into the upper or lower end of the kidney. This research aimsto observe the incidence of anatomical variations of the afferent renal artery and quantify both right and leftkidney weight.Materials and Methods:We analyzed kidney weights and accessory renal artery variations in48 adult kidneys of both genders obtained from Institute of Anatomy of the University of Severino Sombra.Subsequently, we compared the mean weights of kidneys in order to ascertain whether there was significantdiscrepancy between the left and the right kidney. For this, we performed the Student t test considering aP < 0.05.Results:The mean weight of the right kidney was 140.4 ± 22.6 g and the left was 148.8 ± 20.5 g.In 40% of right kidneys was observed anatomic variation with the presence of accessory renal artery. To the leftkidney was observed a variation of 35%.Conclusion:We found that the accessory renal artery, when present,was more closely related to the end of the kidney especially in the right kidney.


Asunto(s)
Humanos , Masculino , Femenino , Arteria Renal/anatomía & histología , Tamaño de los Órganos , Estudios de Evaluación como Asunto
4.
Braz J Biol ; 70(3 Suppl): 737-46, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21085780

RESUMEN

In arid and semiarid environments, seasonality usually exerts a strong influence on the composition and dynamics of the soil community. The soil macroarthropods were studied in a Caatinga forest located in the Reserva Particular do Patrimônio Natural (RPPN) Fazenda Almas, São José dos Cordeiros, Paraíba, Brazil. Samples were collected during the dry and rainy seasons following the method proposed by the Tropical Soil Biology and Fertility Program (TSBF), with minor modifications. At each station, 15 soil blocks (20 × 20 × 30 cm: 12 L) were extracted and divided into three layers: A (0-10 cm), B (10-20 cm), and C (20-30 cm). In the rainy and dry seasons 1,306 ± 543(se) and 458 ± 212 ind.m-2 macroarthropods were found, respectively, with 35 and 18 respective taxa recorded. The abundance of individuals and taxa were significantly higher in the rainy season. Isoptera (57.8%) was the most abundant taxon, followed by Hymenoptera: Formicidae (17.2%), Coleoptera larvae (7.3%), and Araneae (3.5%). In the rainy season, abundance in layer A (576 ± 138 ind.m-2) was significantly higher than that of layer C (117 ± 64 ind.m-2), but was not different from layer B (613 ± 480 ind.m-2). There was also no difference between the layer B and C abundances. In the dry season, abundance in layer B (232 ± 120 ind.m-2) was not significantly different compared to layer A (182 ± 129 ind.m-2), but was significantly higher than abundance in layer C (44 ± 35 ind.m-2). During the rainy season, layer A (34 taxa) was significantly richer in taxa than layers B (19 taxa) and C (11 taxa). On the other hand, during the dry season the richness of layers A (12 taxa) and B (12 taxa) was equal, but significantly higher than that of layer C (6 taxa). Richness of taxa and abundance were positively correlated with soil organic matter and negatively correlated with soil temperature. The community of soil macroarthropods in the area of Caatinga studied has taxonomic and functional structures that are relatively complex and is therefore likely to exert an influence on ecosystem productivity due to its physical effects on soil profile and necromass fragmentation, as occurs in other arid and semiarid ecosystems throughout the world.


Asunto(s)
Artrópodos/clasificación , Ecosistema , Suelo , Árboles , Animales , Brasil , Densidad de Población , Dinámica Poblacional , Estaciones del Año
5.
Ann Trop Med Parasitol ; 103(2): 129-43, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19208297

RESUMEN

Between the April and July of 2007, patients undergoing treatment for schistosomal liver fibrosis, at a university hospital in north-eastern Brazil, were examined by transthoracic Doppler echocardiography (TTE). The main aim was to determine the prevalence of pulmonary hypertension in the patients. The thorax of each patient who had such hypertension, as indicated by an estimated pulmonary arterial systolic pressure (PASP) in excess of 35 mmHg, was then investigated by contrast-enhanced multidetector-row computed tomography (MDCT). The 84 patients (53 women and 31 men) enrolled in the study had a mean (S.D.) age of 50.06 (12.25) years. Nine (10.7%, with a 95% confidence interval of 5.0%-19.4%) of the patients were found to have pulmonary hypertension, with PASP ranging from 40-126 mmHg, and a median (S.D.) PASP of 58.78 (28.01) mmHg. The contrast-enhanced thoracic MDCT indicated that most of the patients with pulmonary hypertension had a pulmonary artery trunk that was unusually wide (67%) and more than 1.1-fold wider than the ascending aorta (56%), dilatation of the main pulmonary arteries (100%), a segmental artery that, in diameter, was more than 1.1-fold larger than the adjacent bronchi (89%), tapering of the peripheral pulmonary arteries (78%), and cardiac enlargement (78%). No patient suffered pulmonary embolism as a result of the investigations. The prevalence of pulmonary hypertension in the patients with schistosomal liver fibrosis (10.7%) justifies the screening of such patients by TTE.


Asunto(s)
Hipertensión Pulmonar/parasitología , Cirrosis Hepática/parasitología , Parasitosis Hepáticas/complicaciones , Esquistosomiasis mansoni/complicaciones , Adulto , Anciano , Ecocardiografía Doppler , Femenino , Volumen Espiratorio Forzado , Humanos , Hipertensión Pulmonar/diagnóstico por imagen , Hipertensión Pulmonar/fisiopatología , Cirrosis Hepática/fisiopatología , Parasitosis Hepáticas/diagnóstico por imagen , Parasitosis Hepáticas/fisiopatología , Masculino , Persona de Mediana Edad , Arteria Pulmonar/diagnóstico por imagen , Arteria Pulmonar/patología , Esquistosomiasis mansoni/diagnóstico por imagen , Esquistosomiasis mansoni/fisiopatología , Fumar/efectos adversos , Tomografía Computarizada por Rayos X , Capacidad Vital , Adulto Joven
6.
Braz J Infect Dis ; 5(6): 339-44, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12010598

RESUMEN

Diarrhea due to intestinal microbial infections is a frequent manifestation among HIV-infected patients. It has been postulated that HIV-infected patients may have special types of intestinal infections, and that immune activation from such parasites may affect the progression of HIV disease. To evaluate these associations, the frequency of infections was examined in HIV-infected patients in Bahia, Brazil. To determine the potential impact of the presence of intestinal parasitic infections on HIV disease progression, a retrospective study approach was used. The medical charts of 365 HIV-infected patients who had been treated at the AIDS Clinic of the Federal University of Bahia Hospital were reviewed, and the prevalence of parasites was compared with 5,243 HIV-negative patients who had attended the hospital during the same period of time. Among HIV-infected subjects, CD(4) count, RNA plasma viral load (VL), and number of eosinophils were compared according to their stool examination results. The overall prevalence of each parasite was similar for HIV-positive and HIV-negative patients. However, the prevalence of S. stercoralis (p<10(-7)) and G. lamblia (p=0.005) was greater for HIV-infected subjects. The mean CD(4) count and viral load of HIV patients in our clinic who had stool examinations was 350 cells +/- 340 and 4.4 +/- 1.4 log RNA viral load, respectively. In this patient group there was no clear association between the level of the absolute CD(4) count or the viral load and a specific parasitic infection. The presence of an intestinal parasitic infection was not associated with faster progression of the HIV disease among HIV-infected patients. We conclude that strongyloidiasis and giardiasis are more frequent in HIV-infected patients in Bahia, Brazil. If this association is due to immune dysregulation, as has been proposed elsewhere, it must occur in patients after only minor shifts in CD(4) count from normal levels, or as a result of immune dysfunction not represented by CD(4) count. These infections do not appear to alter the progression of HIV disease.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Giardiasis/epidemiología , Estrongiloidiasis/epidemiología , Infecciones Oportunistas Relacionadas con el SIDA/parasitología , Adulto , Animales , Brasil/epidemiología , Recuento de Linfocito CD4 , Heces/parasitología , Femenino , Giardia lamblia/aislamiento & purificación , Giardiasis/parasitología , VIH-1/fisiología , Humanos , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Masculino , Persona de Mediana Edad , Prevalencia , ARN Viral/sangre , Estudios Retrospectivos , Strongyloides stercoralis/aislamiento & purificación , Estrongiloidiasis/parasitología , Carga Viral
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