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961.
A missense mutation in the gene encoding the alpha(2) subunit of the Na(+),K(+) ATPase pump (ATP1A2) was found in a family with both familial hemiplegic migraine (FHM) and Benign Familial Infantile Seizures (BFIC). As it is still unclear whether ATP1A2 is responsible for pure BFIC syndromes, we checked mutations of the ATP1A2 gene in probands of 12 Italian multiplex families with pure BFIC, who were negative for mutations in the SCN2A gene. We screened the ATP1A2 gene by denaturing high performance liquid chromatography (D-HPLC) and direct sequencing of DNA fragments showing an aberrant elution pattern. We found one exonic variant and five intronic variants, none leading to significant amino acid changes or causing a modification of the physiological mRNA maturation. The ATP1A2 gene does not appear to be involved in the ethiopathogenesis of pure BFIC syndromes, at least in the explored Italian multiplex families. It could be either responsible of a minority of cases, or of complex syndromes where BFIC and FHM co-occur.  相似文献   
962.
Murine plasmacytoid dendritic cells (pDCs) have been credited with a unique ability to express indoleamine 2,3-dioxygenase (IDO) function and mediate immunosuppression in specific settings; yet, the conditions of spontaneous versus induced activity have remained unclear. We have used maneuvers known to up-regulate IDO in different cell types and have examined the relative efficacy and mechanisms of the induced activity in splenic pDCs, namely, after specific receptor engagement by CTLA-4-Ig, CD200-Ig or CD28-Ig, the latter in combination with silenced expression of the suppressor of cytokine signaling 3 (SOCS3) gene. We found that pDCs (CD11c+ mPDCA-1+ 120G8+) do not express IDO and are not tolerogenic under basal conditions. B7-1 engagement by CTLA-4-Ig, CD200R1 engagement by CD200-Ig and B7-1/B7-2 engagement by CD28-Ig in SOCS3-deficient pDCs were each capable of initiating IDO-dependent tolerance via different mechanisms. IFN-gamma was the major cytokine responsible for CTLA-4-Ig effects, and type I IFNs for those of CD200-Ig. Immunosuppression by CD28-Ig in the absence of SOCS3 required IFN-gamma induction and IFN-like actions of IL-6. Therefore, although pDCs do not mediate IDO-dependent tolerance constitutively, multiple ligands and cytokines will contribute to the expression of a tolerogenic phenotype by pDCs in the mouse.  相似文献   
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Vitamin D is a fat-soluble pro-hormone that plays an important role in bone homeostasis; beside this principal function, vitamin D promotes modulation of cell growth, neuromuscular and immune function, and reduction of inflammation. In addition, several in vitro and in vivo studies have demonstrated that vitamin D deficiency could increase the risk of cancer, autoimmune and cardiovascular diseases. Moreover, vitamin D plays also an important role in female reproduction, because vitamin D receptors are expressed in ovarian tissue, endometrium, fallopian epithelial cells as well as in decidua and placenta. We aimed to review the most updated evidence, which suggests a link between vitamin D metabolism and the development of some gynaecological diseases, such as endometriosis, uterine fibroids and polycystic ovary syndrome.  相似文献   
968.
BackgroundVulvovaginal candidiasis (VVC) is the second most common infection of the genital tract affecting millions of women worldwide. Data concerning the distribution and antifungal resistance of Candida species responsible of VVC vary among countries and population studied. Objectives: The aim of this work was to determine the prevalence, species distribution and antifungal susceptibility patterns of Candida species among symptomatic women over a 20-year period.MethodsA total of 5,820 unique samples were retrospectively identified. Out of them, 1,046 (18%) were diagnosed with VVC.ResultsWomen between 18 and 30 years had the highest prevalence rate of VVC (21%). Women aged less than 18 years and greater than 51 years had the highest prevalence rates of vaginal bacterial infections. Thirty-five (3.3%) women presented recurrent VVC. The most common yeast isolated was C. albicans, followed by C. glabrata, C. krusei, and C. parapsilosis. Non-Candida albicans species (NAC) were more significantly isolated among women aged 51 or above, than in women included in other groups (p < 0.01). Resistance to fluconazole and amphotericin B was infrequent in C. albicans strains. Resistance to fluconazole and amphotericin B was infrequent in C. albicans strains. NAC species presented higher resistance rates against fluconazole (30%) and voriconazole (25%). C. krusei and C. glabrata isolates showed lower MICs than most of the strains against amphotericin B (1 mg/L) and flucytosine (1 mg/L).ConclusionsOur findings indicated that continued surveillance on Candida species distribution and non-susceptibility rates to antifungals should be routinely reported to help the selection of the most appropriate drug, to avoid the emergence of resistant strains, and to improve the patient's outcomes.  相似文献   
969.
Medulloblastomas are brain tumors that arise in the cerebellum of children and contain stem cells in a perivascular niche thought to give rise to recurrence following radiation. We used several mouse models of medulloblastomas in parallel to better understand how the critical cell types in these tumors respond to therapy. In our models, the proliferating cells in the tumor bulk undergo radiation-induced, p53-dependent apoptotic cell death. Activation of Akt signaling via PTEN loss transforms these cells to a nonproliferating extensive nodularity morphology. By contrast, the nestin-expressing perivascular stem cells survive radiation, activate PI3K/Akt pathway, undergo p53-dependent cell cycle arrest, and re-enter the cell cycle at 72 h. Furthermore, the ability of these cells to induce p53 is dependent on the presence of PTEN. These cellular characteristics are similar to human medulloblastomas. Finally, inhibition of Akt signaling sensitizes cells in the perivascular region to radiation-induced apoptosis.  相似文献   
970.
We evaluated the efficacy of enrofloxacin, alone or combined with metronidazole, against Leishmania infantum. The in vitro activity of this fluoroquinolone was assessed using two different methods: a direct test aimed at assessing the drug activity on the parasite, and an indirect test aimed at evaluating the drug effect on macrophage killing, lymphomonocyte activation and nitric oxide production. An in vivo test was also performed on 36 dogs with leishmaniasis, subdivided into three groups, one treated with enrofloxacin, another with enrofloxacin plus metronidazole, and a control group with meglumine antimoniate. The direct test did not show any action of enrofloxacin on the parasite, while the indirect testing showed an enhancement of macrophage killing and an increase in nitric oxide production. These findings show that enrofloxacin does not exert a direct anti-leishmanial activity in vitro. However, on the basis of the positive immunostimulation results shown in vitro and the clinical improvement, particularly of the cutaneous lesions, obtained in several dogs in the in vivo trial, the use of enrofloxacin in association with a specific anti-leishmanial drug can be proposed in the therapeutic protocol of canine leishmaniasis.  相似文献   
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