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A comprehensive analysis of Staphylococcus aureus superantigen (SAG) genes was undertaken in isolates from a major hospital and compared with isolates from patients with toxic shock syndrome (TSS). Polymerase chain reaction (PCR) analysis included recently discovered SAGs. Staphylococcal enterotoxin (SE) G and SEI were uniquely expressed in genital isolates. Genital isolates were similar to TSS isolates, although the latter frequently expressed TSS toxin 1. Both had a high frequency of SEG/SEI and a high number of SAG genes per bacterium. Detection of an SAG gene by PCR correlated with positive results in functional assays for SAG activity. Levels of serum antibodies to SEG and SEI, but not to other superantigens, were higher in healthy women than in men and served as an independent measure of the higher frequency of exposure to SEG/SEI among women. Together, the data suggest a role for SEG/SEI or closely linked genes in the adaptation of S. aureus to the genital mucosa environment.  相似文献   
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Despite the known benefits of continued sexual activity on physical, mental, and emotional health, the nursing home resident continues to be sexually invisible. There are so few opportunities where the quality of life can be enhanced so greatly by so basic interventions. Sexuality in the nursing home is one of them. Failure of society to come to grips with the sexual needs of the elderly essentially robs them of a fundamental element of self-worth.  相似文献   
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Depletion of total antioxidant capacity in type 2 diabetes   总被引:4,自引:0,他引:4  
The purpose of the study was to examine the relationship between antioxidant depletion, glycemic control, and development of chronic complications in a controlled population of type 2 diabetic patients. Fifty age-matched type 2 diabetic patients receiving sulfonylureas but not insulin treatment were screened and assigned to two groups based on the presence or absence of proteinuria. A third group of normal subjects without diabetes were also enrolled in the study. All subjects in the three groups were Egyptians who were matched for body weight, and the two diabetic groups were also age-matched. Plasma glucose and fructosamine levels were higher in the two groups of diabetic patients versus the control group, but lipid peroxide levels were higher only in the patients with proteinuria. Compared with the control group, the total antioxidant capacity was depleted in the two diabetic groups, but the depletion was more severe in patients with proteinuria. Thus, the mean Trolox equivalent antioxidant capacity (TEAC) of the control group was 2.7+/-0.45, versus 1.7+/-0.5 (P < .001) in the patients without proteinuria. Furthermore, the TEAC measured in patients with proteinuria, who also had more diabetic complications, was lower (1.4+/-0.5, P < .001) than the TEAC in patients without urinary protein. In conclusion, a depletion of the total antioxidant capacity is associated with a higher incidence of diabetic complications.  相似文献   
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Interleukin 8 (IL-8), is a proinflammatory chemokine, has been reported to have angiogenic activity and to be responsible for tumor-associated angiogenesis in several cancers. In this study, we aimed to study the (IL-8) gene polymorphism in relation with risk development of non small cell lung cancer in Tunisian patient. Two single nucleotide polymorphisms (−251T/A [rs4073], +781C/T [rs2227306]) of the IL-8 gene were screened in 170 patients with NSCLC and 225 healthy controls by PCR–RFLP.  相似文献   
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In skeletal muscle, excitation–contraction (EC) coupling is the process whereby the voltage‐gated dihydropyridine receptor (DHPR) located on the transverse tubules activates calcium release from the sarcoplasmic reticulum by activating ryanodine receptor (RyR1) Ca2+ channels located on the terminal cisternae. This subcellular membrane specialization is necessary for proper intracellular signaling and any alterations in its architecture may lead to neuromuscular disorders. In this study, we present evidence that patients with recessive RYR1‐related congenital myopathies due to primary RyR1 deficiency also exhibit downregulation of the alfa 1 subunit of the DHPR and show disruption of the spatial organization of the EC coupling machinery. We created a cellular RyR1 knockdown model using immortalized human myoblasts transfected with RyR1 siRNA and confirm that knocking down RyR1 concomitantly downregulates not only the DHPR but also the expression of other proteins involved in EC coupling. Unexpectedly, this was paralleled by the upregulation of inositol‐1,4,5‐triphosphate receptors; functionally however, upregulation of the latter Ca2+ channels did not compensate for the lack of RyR1‐mediated Ca2+ release. These results indicate that in some patients, RyR1 deficiency concomitantly alters the expression pattern of several proteins involved in calcium homeostasis and that this may influence the manifestation of these diseases.  相似文献   
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This article presents the annealing effect on the structural, elastic, thermodynamic, optical, magnetic, and electric properties of Ni0.6Zn0.4Fe1.5Al0.5O4 (NZFAO) nanoparticles (NPs). The samples were successfully synthesized by the sol–gel method followed by annealing of the as-synthesized at 600, 800, 900, 1050, and 1200 °C. This approach yielded the formation of a highly crystalline structure with crystallite size ranging from 17 nm to 40 nm. X-ray diffraction (XRD), scanning electron microscopy (SEM) techniques, as well as energy disperse spectroscopy (EDS), Fourier transform infrared (FTIR) and Raman spectroscopy, were used in order to determine the structural and morphological properties of the prepared samples. Rietveld XRD refinement reveals that Ni–Zn–Al ferrite nanoparticles crystallize in inverse cubic (Fd3̄m) spinel structure. Using FTIR spectra, the elastic and thermodynamic properties were estimated. It was observed that the particle size had a pronounced effect on elastic and thermodynamic properties. Magnetic measurements were performed up to 700 K. The prepared ferrite samples present the highest Curie temperature, which decreases with increasing particle size and which is consistent with finite-size scaling. The thickness of the surface shell of about 1 nm was estimated from size-dependent magnetization measurements using the core–shell model. Besides, spin resonance, magnetostriction, temperature coefficient of resistance (TCR), and electrical resistivity properties have been scientifically studied and appear to be different according to their size. The optical properties of synthesized NZFAO nanoparticles were investigated, and the differences caused by the particle sizes are discussed on the basis of the phonon confinement effect. This effect was also inspected by the Raman analysis. Tuning of the physical properties suggests that the Ni–Zn–Al ferrite samples may be promising for multifunctional diverse applications.

This article presents the annealing effect on the structural, elastic, thermodynamic, optical, magnetic, and electric properties of Ni0.6Zn0.4Fe1.5Al0.5O4 (NZFAO) nanoparticles (NPs).  相似文献   
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