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91.

OBJECTIVE:

This study aimed to determine the frequency of the PROGINS polymorphism in women with endometriosis‐associated infertility, in infertile women without endometriosis and in controls.

INTRODUCTION:

The human progesterone receptor gene has two isoforms that modulate the biological action of progesterone: isoform A, which is capable of inhibiting the activation of the estrogen receptors, and isoform B, which has the capacity to activate the estrogen receptors. Several polymorphisms have been described for this gene, among which one stands out: a polymorphism named PROGINS, which has been speculated to be related to the genesis of endometriosis by several studies with conflicting results.

METHODS:

This was a prospective study that included 148 patients with endometriosis‐associated infertility, 50 idiopathic infertile patients and 179 fertile women as controls. The PROGINS polymorphism was studied by PCR.

RESULTS:

Genotypes P1P1, P1P2 and P2P2 (P2 representing the PROGINS polymorphism) of the progesterone receptor gene presented frequencies of 93.9%, 5.4% and 0.7%, respectively, in the women with endometriosis‐associated infertility (p = 0.2101, OR = 0.51, 95% CI = 0.24‐1.09); 94.4%, 4.2% and 1.4%, respectively, in the patients with minimal/mild endometriosis (p = 0.2725, OR = 0.53, 95% CI = 0.20‐1.43); 93.5%, 6.5% and 0%, respectively, among the patients with moderate/severe endometriosis (p = 0.3679, OR = 0.49, 95% CI = 0.18‐1.31); 86.0%, 14.0% and 0%, respectively, in idiopathic infertile women (p = 0.8146, OR = 1.10, 95% CI = 0.46‐2.63); and 88.3%, 10.6% and 1.1%, respectively, in the control group.

CONCLUSION:

The data suggest that PROGINS is not related either to endometriosis‐associated infertility or to idiopathic infertility in the population studied.  相似文献   
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Plasma lipoproteins such as LDL (low‐density lipoprotein) are important therapeutic targets as they play a crucial role in macrophage biology and metabolic disorders. The impact of lipoprotein profiles on host defense pathways against Gram‐positive bacteria is poorly understood. In this report, we discovered that human serum lipoproteins bind to lipoteichoic acid (LTA) from Staphylococcus aureus and thereby alter the immune response to these bacteria. Size‐exclusion chromatography and solid‐phase‐binding analysis of serum revealed the direct interaction of LTA with apolipoproteins (Apo) B100, ApoA1, and ApoA2. Only ApoB100 and the corresponding LDL exerted biological effects as this binding significantly inhibited LTA‐induced cytokine releases from human and murine immune cells. Serum from hypercholesterolemic mice or humans significantly diminished cytokine induction in response to S. aureus or its LTA. Sera taken from the patients with familial hypercholesterolemia before and after ApoB100‐directed immuno‐apheresis confirmed that ApoB100 inhibited LTA‐induced inflammation in humans. In addition, mice in which LDL secretion was pharmacologically inhibited, displayed significantly increased serum cytokine levels upon infection with S. aureus in vivo. The present study identifies ApoB100 as an important suppressor of innate immune activation in response to S. aureus and its LTA.  相似文献   
95.
In the present work we evaluated a variety of indicators of oxidative stress in distinct brain regions (striatum, cerebral cortex and hippocampus), the liver, and heart of 30-day-old glutaryl-CoA dehydrogenase deficient (Gcdh(-/-)) mice. The parameters evaluated included thiobarbituric acid-reactive substances (TBA-RS), 2-7-dihydrodichlorofluorescein (DCFH) oxidation, sulfhydryl content, and reduced glutathione (GSH) concentrations. We also measured the activities of the antioxidant enzymes glutathione peroxidase (GPx), glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD) and glucose-6-phosphate dehydrogenase (G6PD). Under basal conditions glutaric (GA) and 3-OH-glutaric (3OHGA) acids were elevated in all tissues of the Gcdh(-/-) mice, but were essentially absent in WT animals. In contrast there were no differences between WT and Gcdh(-/-) mice in any of the indicators or oxidative stress under basal conditions. Following a single intra-peritoneal (IP) injection of lysine (Lys) there was a moderate increase of brain GA concentration in Gcdh(-/-) mice, but no change in WT. Lys injection had no effect on brain 3OHGA in either WT or Gcdh(-/-) mice. The levels of GA and 3OHGA were approximately 40% higher in striatum compared to cerebral cortex in Lys-treated mice. In the striatum, Lys administration provoked a marked increase of lipid peroxidation, DCFH oxidation, SOD and GR activities, as well as significant reductions of GSH levels and GPx activity, with no alteration of sulfhydryl content, CAT and G6PD activities. There was also evidence of increased lipid peroxidation and SOD activity in the cerebral cortex, along with a decrease of GSH levels, but to a lesser extent than in the striatum. In the hippocampus only mild increases of SOD activity and DCFH oxidation were observed. In contrast, Lys injection had no effect on any of the parameters of oxidative stress in the liver or heart of Gcdh(-/-) or WT animals. These results indicate that in Gcdh(-/-) mice cerebral tissue, particularly the striatum, is at greater risk for oxidative stress than peripheral tissues following Lys administration.  相似文献   
96.
BACKGROUND: Combined hormone treatments in post-menopausal women have different clinical responses on uterus and vagina; therefore, we investigated differences in steroid signalling between various hormone therapies in these tissues. METHODS: A total of 30 post-menopausal women scheduled for hysterectomy were distributed into four subgroups: control-group (n = 9), Tibolone-group (n = 8); estradiol (E(2))-group (n = 7); E(2) + medroxyprogesterone acetate (MPA)-group (n = 6). Medication was administered orally every day for 21 days prior to removal of uterus and upper part of the vagina. Tissue RNA was isolated, and gene expression profiles were generated using GeneChip technology and analysed by cluster analysis and significance analysis of microarrays. Apoptosis and cell proliferation assays, as well as immunohistochemistry for hormone receptors were performed. RESULTS: 21-days of treatment with E(2), E(2) + MPA or tibolone imposes clear differential gene expression profiles on endometrium and myometrium. Treatment with E(2) only results in the most pronounced effect on gene expression (up to 1493 genes differentially expressed), proliferation and apoptosis. Tibolone, potentially metabolized to both estrogenic and progestagenic metabolites, shows some resemblance to E(2) signalling in the endometrium and, in contrast, shows significant resemblance to E(2) + MPA signalling in the myometrium. In the vagina the situation is entirely different; all three hormonal treatments result in regulation of a small number (4-73) of genes, in comparison to signalling in endometrium and myometrium. CONCLUSION: Endometrium and myometrium differentially respond to the hormone therapies and use completely different sets of genes to regulate similar biological processes, while in this experiment the upper part of the vagina is hardly hormone responsive.  相似文献   
97.
Appropriate murine models of shrimp tropomyosin (ST) allergy would be useful in investigating the mechanisms underlying food allergy in human subjects, as well as for the pre-clinical evaluation of efficacy and safety of novel therapeutic approaches. These models should mimic immune and clinical features of human disease, including anaphylactic response. We sensitized C3H/HeJ mice by the oral route with purified ST using cholera toxin (CT) as adjuvant. ST-specific IgE, IgG1, IgG2a and IgA responses were evaluated by ELISA. Spleen cell proliferation and cytokine production by allergen-specific activation were assessed. Jejunum and colon fragments were collected to evaluate the local expression of cytokine genes by PCR. Local and systemic anaphylactic reactions induced by oral ST challenge were scored according to symptoms observed. Faecal samples were collected to assess local IgA production and histamine levels. Oral sensitization with ST plus CT induced in mice significant levels of serum IgE and IgG1 and faecal IgA. ST-specific cell proliferation and IL-4, IL-13 and IFN-gamma cytokine production were induced in the spleen. After oral challenge, 100% of mice had anaphylactic symptoms while no symptoms were observed in challenged naive mice. Faecal histamine content after ST challenge appeared significantly increased in sensitized mice when compared with that observed in pre-immune mice. Jejunum mRNA expression of T(h)2 cytokines was up-regulated by ST sensitization. These results support the importance of the oral way of sensitization and of the in-depth characterization of the anaphylactic response for the development of a suitable in vivo model of food allergy.  相似文献   
98.
Stenotrophomonas maltophilia is a microorganism of environmental and clinical importance as well as a frequent airway colonizer of cystic fibrosis (CF) individuals. We combined 2-DE and MALDI-TOF MS to profile the protein expression in S. maltophilia K279a, a completely sequenced clinical isolate, grown at 37 °C with respect to the strain grown at 26 °C. Among the proteins up-regulated at 37 °C, we identified GroEL, a molecular chaperone that mainly assist the folding and unfolding of proteins under both normal and stress conditions. A 2.4-kb groESL mRNA was detected independently by Northern blot analyses with a groES- and a groEL-specific probe, indicating that S. maltophilia groES and groEL form an operon. Primer extension analysis of S. maltophilia groESL done in Escherichia coli showed that 2 promoters, Pσ(32) and Pσ(70), were utilized under the heat-shock and normal condition, respectively, whereas S. maltophilia groEL was shown to act as a heat-shock gene at 37 °C, 42 °C, and, to a lesser extent, at 50 °C by real-time RT-PCR analyses. Finally, immunoblot analyses revealed that S. maltophilia GroEL strongly reacted with sera from CF patients chronically infected by the microorganism, but did not with sera from CF patients with sporadic infection or uninfected.  相似文献   
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We present two cases of juvenile form of paracoccidioidomycosis (PCM), a systemic mycosis frequently found in rural areas, whose prognosis is poor in children and young adults. They are a 14-year-old boy and a 25-year-old woman, both residents in an urban area in São Paulo – Brazil, without any history of travelling to an endemic area. They have been admitted to the hospital due to fever, weight loss and lymphadenopathy. The diagnosis was confirmed by serologic and histopathologic study. Patients have recovered after therapy with oral itraconazole and were discharged from hospital, maintaining outpatient visits. In this article, the authors discuss the unusual presentation of PCM in an urban area.  相似文献   
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