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

RESUMO

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
Artigo em Inglês | LILACS | ID: lil-699334

RESUMO

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.


Assuntos
Humanos , Masculino , Feminino , Artéria Renal/anatomia & histologia , Tamanho do Órgão , Estudos de Avaliação como Assunto
4.
Braz J Infect Dis ; 5(6): 339-44, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12010598

RESUMO

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.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Giardíase/epidemiologia , Estrongiloidíase/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/parasitologia , Adulto , Animais , Brasil/epidemiologia , Contagem de Linfócito CD4 , Fezes/parasitologia , Feminino , Giardia lamblia/isolamento & purificação , Giardíase/parasitologia , HIV-1/fisiologia , Humanos , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Masculino , Pessoa de Meia-Idade , Prevalência , RNA Viral/sangue , Estudos Retrospectivos , Strongyloides stercoralis/isolamento & purificação , Estrongiloidíase/parasitologia , Carga Viral
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