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21.

Background  

Schistosomiasis affects the reproductive health of women. Described sequelae are ectopic pregnancy, infertility, abortion, and cervical lesions and symptoms mimicking cervical cancer and STIs. There are indications that cervical schistosomiasis lesions could become co-factors for viral infection such as HIV and HPV.  相似文献   
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23.

Background

Dietary habits and depression are associated with cardiovascular disease risk. Patients with depression often report poor eating habits, and dietary factors may help explain commonly observed associations between depression and cardiovascular disease.

MethodS

From 1996 to 2000, 936 women were enrolled in the Women's Ischemia Syndrome Evaluation at 4 US academic medical centers at the time of clinically indicated coronary angiography and then assessed (median follow-up, 5.9 years) for adverse outcomes (cardiovascular disease death, heart failure, myocardial infarction, stroke). Participants completed a protocol including coronary angiography (coronary artery disease severity) and depression assessments (Beck Depression Inventory scores, antidepressant use, and depression treatment history). A subset of 201 women (mean age, 58.5 years; standard deviation, 11.4) further completed the Food Frequency Questionnaire for Adults (1998 Block). We extracted daily fiber intake and daily servings of fruit and vegetables as measures of dietary habits.

Results

In separate Cox regression models adjusted for age, smoking, and coronary artery disease severity, Beck Depression Inventory scores (hazard ratio [HR], 1.05; 95% confidence interval [CI], 1.01-1.10), antidepressant use (HR, 2.4; 95% CI, 1.01-5.9), and a history of treatment for depression (HR, 2.4; 95% CI, 1.1-5.3) were adversely associated with time to cardiovascular disease outcomes. Fiber intake (HR, 0.87; 95% CI, 0.78-0.97) and fruit and vegetable consumption (HR, 0.36; 95% CI, 0.19-0.70) were associated with a decreased time to cardiovascular disease event risk. In models including dietary habits and depression, fiber intake and fruit and vegetable consumption remained associated with time to cardiovascular disease outcomes, whereas depression relationships were reduced by 10% to 20% and nonsignificant.

Conclusions

Among women with suspected myocardial ischemia, we observed consistent relationships among depression, dietary habits, and time to cardiovascular disease events. Dietary habits partly explained these relationships. These results suggest that dietary habits should be included in future efforts to identify mechanisms linking depression to cardiovascular disease.  相似文献   
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25.
Recent studies suggest a synergic effect of infection and hypoxia-ischemia in the causation of perinatal brain damage. We conducted a prospective pilot study on the presence of infection in hypoxic-ischemic encephalopathy (HIE), focusing on neurotropic viruses. Sixteen newborns with HIE were included in the study. There were no confirmed cases of viral infection. There was a case of bacterial early onset sepsis and four cases of suspected sepsis due to clinical and/or analytical signs, but with negative cultures. Our results do not support universal screening for viral infection in cases of HIE.  相似文献   
26.
Allergen exposure and rhinovirus (RV) infections are common triggers of acute wheezing exacerbations in early childhood. The identification of such trigger factors is difficult but may have therapeutic implications. Increases of IgE and IgG in sera, were shown against allergens and the N-terminal portion of the VP1 proteins of RV species, respectively, several weeks after allergen exposure or RV infection. Hence, increases in VP1-specific IgG and in allergen-specific IgE may serve as biomarkers for RV infections or allergen exposure. The MeDALL-allergen chip containing comprehensive panels of allergens and the PreDicta RV chip equipped with VP1-derived peptides, representative of three genetic RV species, were used to measure allergen-specific IgE levels and RV-species-specific IgG levels in sera obtained from 120 preschool children at the time of an acute wheezing attack and convalescence. Nearly 20% of the children (22/120) showed specific IgE sensitizations to at least one of the allergen molecules on the MeDALL chip. For 87% of the children, increases in RV-specific IgG could be detected in the follow-up sera. This percentage of RV-specific IgG increases was equal in IgE-positive and -negative children. In 10% of the children, increases or de novo appearances of IgE sensitizations indicative of allergen exposure could be detected. Our results suggest that, in the majority of preschool children, RV infections trigger wheezing attacks, but, in addition, allergen exposure seems to play a role as a trigger factor. RV-induced wheezing attacks occur in IgE-sensitized and non-IgE-sensitized children, indicating that allergic sensitization is not a prerequisite for RV-induced wheeze.  相似文献   
27.
Muta  K; Krantz  SB; Bondurant  MC; Dai  CH 《Blood》1995,86(2):572-580
Stem cell factor (SCF), the ligand for the c-kit tyrosine kinase receptor, markedly stimulates the accumulation of erythroid progenitor cells in vitro. We now report that SCF delays erythroid differentiation among the progeny of individual erythroid progenitors while greatly increasing the proliferation of these progeny. These effects appear to be independent of an effect on maintenance of cell viability. Highly purified day-6 erythroid colony-forming cells (ECFC), consisting mainly of colony-forming units-erythroid (CFU-E), were generated from human peripheral blood burst-forming units-erythroid (BFU-E). Addition of SCF to the ECFC in serum-free liquid culture, together with erythropoietin (EP) and insulin-like growth factor 1 (IGF-1), resulted in a marked increase in DNA synthesis, associated with a delayed peak in cellular benzidine positivity and a delayed incorporation of 59Fe into hemoglobin compared with cultures without SCF. In the presence of SCF, the number of ECFC was greatly expanded during this culture period, and total production of benzidine-positive cells plus hemoglobin synthesis were ultimately increased. To determine the effect of SCF on individual ECFC, single-cell cultures were performed in both semisolid and liquid media. These cultures demonstrated that SCF, in the presence of EP and IGF-1, acted on single cells and their descendants to delay erythroid differentiation while substantially stimulating cellular proliferation, without an enhancement of viability of the initial cells. This was also evident when the effect of SCF was determined using clones of ECFC derived from single BFU-E. Our experiments demonstrate that SCF acts on individual day-6 ECFC to retard erythroid differentiation while simultaneously providing enhanced proliferation by a process apparently independent of an effect on cell viability or programmed cell death.  相似文献   
28.
The Friend polycythemia virus complex (FVP), consisting of the replication-defective spleen focus-forming virus (SFFV) and a helper Friend murine leukemia virus (MuLV-F), produces erythroleukemia within 2-3 weeks in vivo. We have recently reported in vitro transformation of bone marrow cells by FVP, producing clusters of erythroid colonies (erythroid bursts) 4-6 days after infection. In contrast to uninfected bone marrow cells, FVP-treated cells proliferated and differentiated (synthesized hemoglobin) in the absence of added erythropoietin, the physiologic regulator of erythropoiesis. The relative roles of helper murine leukemia virus (MuLV) and SFFV in the in vitro erythroid transformation have now been examined. Pseudotype studies and the finding that cloned MuLV-F (free of SFFV) did not induce burst formation indicated that SFFV was essential for this in vitro effect of FVP. Because SFFV could not be obtained free of helper MuLV, we assessed the requirement of MuLV in the transformation by kinetic analyses of helper-deficient and helper-excess FVP preparations. Whereas helper-excess FVP gave single-hit kinetics both in vivo and in vitro, the helper-deficient FVP followed multiple-hit kinetics when titrated for spleen focus formation in vivo. Addition of MuLV-F to helper-deficient FVP prior to injection resulted in a marked enhancement of spleen focus formation and a conversion from multiple-hit to single-hit kinetics. In contrast, titration of this same preparation for erythroid burst transformation in vitro yielded single-hit kinetics, and the addition of helper MuLV-F had no effect. The time course of burst development was similar with or without added MuLV-F. Unlike burst transformation, SFFV production by these infected cultures followed multiple-hit kinetics. Addition of MuLV-F at the time of infection led to an enhancement of SFFV production and conversion of the titration curve from multiple-hit to single-hit. These data are consistent with the idea that SFFV is competent for erythroid transformation in vitro, but requires helper MuLV for its replication.  相似文献   
29.
R S Stein  R I Abels  S B Krantz 《Blood》1991,78(7):1658-1663
Twenty patients with myelodysplastic syndromes (MDS) entered a randomized, placebo-controlled, double-blind trial designed to evaluate the efficacy and toxicity of high doses of recombinant human erythropoietin (rhEPO). Patients completing the trial were eligible to receive rhEPO as part of an open-label study. Eighteen patients were transfusion dependent; 10 had refractory anemia (RA), and 10 had refractory anemia with ringed sideroblasts (RARS). A response to rhEPO was defined as an increase in hematocrit of 4 percentage points or more over baseline, or the elimination of all transfusions with the hematocrit stable at the baseline level. In the double-blind trial, 1 patient (12.5%) receiving rhEPO responded, as compared with no responses in the placebo group. Overall, responses occurred in 4 of 17 patients (24%) receiving rhEPO at a dose of 1,200 to 1,600 U/kg intravenously (IV) twice weekly. Changes in granulocyte or platelet counts were not observed. Despite the administration of high doses of rhEPO, toxicity attributable to rhEPO was not observed in either the double-blind or open-label study. Response to rhEPO was not significantly related to age, gender, type of MDS, time since diagnosis, time since initiation of transfusion therapy, or baseline serum EPO. These studies indicate that rhEPO can be administered safely in very high doses to patients with MDS and that 24% of these patients will respond with increased erythropoiesis.  相似文献   
30.
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