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481.
482.
Michael Saavedra Brad Taylor Nicholas Lukacs Paul L. Fidel Jr. 《Infection and immunity》1999,67(11):5820-5826
Recurrent vulvovaginal candidiasis, caused by Candida albicans, is a significant problem in women of childbearing age. Although cell-mediated immunity (CMI) due to T cells and cytokines is the predominant host defense mechanism against C. albicans at mucosal tissue sites, host defense mechanisms against C. albicans at the vaginal mucosa are poorly understood. Based on an estrogen-dependent murine model of vaginal candidiasis, our data suggest that systemic CMI is ineffective against C. albicans vaginal infections. Thus, we have postulated that local immune mechanisms are critical for protection against infection. In the present study, the kinetic production of chemokines normally associated with the chemotaxis of T cells, macrophages (RANTES, MIP-1alpha, MCP-1), and polymorphonuclear neutrophils (MIP-2) was examined following intravaginal inoculation of C. albicans in estrogen-treated or untreated mice. Results showed significant increases in MCP-1 protein and mRNA in vaginal tissue of infected mice as early as 2 and 4 days postinoculation, respectively, that continued through a 21-day observation period, irrespective of estrogen status. No significant changes were observed with RANTES, MIP-1alpha, or MIP-2, although relatively high constitutive levels of RANTES mRNA and MIP-2 protein were observed. Furthermore, intravaginal immunoneutralization of MCP-1 with anti-MCP-1 antibodies resulted in a significant increase in vaginal fungal burden early during infection, suggesting that MCP-1 plays some role in reducing the fungal burden during vaginal infection. However, the lack of changes in leukocyte profiles in vaginal lavage fluids collected from infected versus uninfected mice suggests that MCP-1 functions to control vaginal C. albicans titers in a manner independent of cellular chemotactic activity. 相似文献
483.
Prevalence rates of hypertension and ischemic heart disease in a rural community in Israel in 1976 were 9.3% and 2.3%, respectively. The rates were related to age, sex, country of origin, education, occupation, marital status, household crowding, and smoking habits. A multiple regression analysis of all variables showed a significantly positive association between the prevalence of hypertension and age, number of children, Cochin or Moroccan origin, and divorce or widowhood. A negative association was found with agricultural work. The prevalence rate of ischemic heart disease correlated positively with age, Cochin origin, and divorce or widowhood. A stepwise linear regression analysis revealed that these variables accounted for 11.3% and 2.8% of the total variance observed, in hypertension and ischemic heart disease respectively. 相似文献
484.
485.
Lateral ventricle tumors in children: a series of 54 cases 总被引:2,自引:0,他引:2
Graciela Zuccaro Fidel Sosa Vicente Cuccia Fabiana Lubieniecky Jorge Monges 《Child's nervous system》1999,15(11-12):774-785
A series of 54 patients with lateral ventricle tumors diagnosed and surgically treated from 1988 to 1998 was reviewed. Neoplasms invading ventricles and originating beyond their walls were excluded. There were 35 male and 19 female patients. Their ages ranged from 15 days to 20 years, and two frequency peaks were observed, one at 2 and one at 11 years. The most frequent signs and symptoms were attributed to increased intracranial pressure. The 54 patients included 41 who developed hydrocephalus, but only 15 of these required shunting. The trigonal region and frontal horn were the most common sites of origin. Surgery was planned with due consideration for the localization of the tumor, its presumptive histology, its main feeding vessels, the parenchymal functionality, and the presence or absence of hydrocephalus. The most frequent tumor types were subependymal giant cell astrocytoma, choroid plexus tumors, ependymoma, and astrocytoma. The most common complications were intraventricular hemorrhage, cortical collapse, subdural collection and seizures. To conclude, tumors located within the lateral ventricles are often very voluminous and are predominantly benign, and the treatment of choice is total resection. In the case of malignancy, postsurgical radiotherapy and/or chemotherapy should be given. 相似文献
486.
Katherine Y. Look M.D. John A. Blessing Ph.D. Fidel A. Valea M.D. Ramon McGehee M.D. Alberto Manetta M.D. Kenneth D. Webster M.D. Willie A. Andersen M.D. 《Gynecologic oncology》1997,67(3):255-258
Objective.The objective of the study was to determine the response rate and associated toxicity of 5-fluorouracil and high-dose leucovorin in patients with recurrent adenocarcinoma of the cervix.Methods.Between December 1993 and October 1995, 53 patients with recurrent adenocarcinoma of the cervix were entered into a Phase II trial utilizing 200 mg/m2of intravenous (iv) leucovorin with 370 mg/m2of iv 5-fluorouracil daily for 5 days every 4 weeks for two courses, then every 5 weeks until disease progression. Eligibility criteria were a Gynecologic Oncology Group (GOG) performance status of 0–2, adequate bone marrow reserve, adequate liver function with bilirubin ≤ 1.5× normal and SGOT and alkaline phosphatase ≤ 3× normal, serum creatinine ≤ 2 mg%, and signed informed consent. Standard GOG toxicity and response criteria were employed.Results.Six patients were ineligible because of wrong cell type (N= 3), insufficient pathology materials (N= 2), or a second primary (N= 1); therefore 45 were evaluable for toxicity. Two patients did not have adequate response assessment; thus, 43 were evaluable for response. The median age was 50 (range, 28–79). Prior chemotherapy had been administered to 16 patients and radiotherapy to 40 patients. The median number of courses delivered was three (range, 1–22). The site of evaluable disease was pelvic in 25 patients and extra–pelvic in 18. Grade 3 neutropenia was seen in 17.8% (8/45) patients and 35.5% (16/45) developed grade 4 neutropenia. Grade 3 or 4 thrombocytopenia was seen in 1 patient each (2.1%). Grade 3 gastrointestinal toxicity with nausea, vomiting, diarrhea, dehydration, or stomatitis was of grade 3 severity in 11.1% (5/45) and grade 4 in 6.7% (3/45). There were four partial responses and two complete responses for an overall response rate of 14%. The duration of the complete responses was 17.3 and 8.8+ months. None of the patients with responses had previously received chemotherapy.Conclusion.The schedule of 5-fluorouracil and leucovorin exhibits moderate activity in patients with previously treated adenocarcinoma of the cervix and should be considered for a trial in chemotherapy-naive patients. 相似文献
487.
Vulvovaginal candidiasis (VVC) is an opportunistic mucosal infection caused by Candida albicans that affects large numbers of otherwise healthy women of childbearing age. Acute episodes of VVC often occur during pregnancy and during the luteal phase of the menstrual cycle, when levels of progesterone and estrogen are elevated. Although estrogen-dependent experimental rodent models of C. albicans vaginal infection are used for many applications, the role of reproductive hormones and/or their limits in the acquisition of vaginal candidiasis remain unclear. This study examined the effects of estrogen and progesterone on several aspects of an experimental infection together with relative cell-mediated immune responses. Results showed that while decreasing estrogen concentrations eventually influenced infection-induced vaginal titers of C. albicans and rates of infection in inoculated animals, the experimental infection could not be achieved in mice treated with various concentrations of progesterone alone. Furthermore, progesterone had no effect on (i) the induction and persistence of the infection in the presence of estrogen, (ii) delayed-type hypersensitivity in primary-infected mice, or (iii) the partial protection from a secondary vaginal infection under pseudoestrus conditions. Other results with estrogen showed that a persistent infection could be established with a wide range of C. albicans inocula under supraphysiologic and near-physiologic (at estrus) concentrations of estrogen and that vaginal fungus titers or rates of infection were similar if pseudoestrus was initiated several days before or after inoculation. However, the pseudoestrus state had to be maintained for the infection to persist. Finally, estrogen was found to reduce the ability of vaginal epithelial cells to inhibit the growth of C. albicans. These results suggest that estrogen, but not progesterone, is an important factor in hormone-associated susceptibility to C. albicans vaginitis. 相似文献
488.
Effects of Cryptococcus neoformans-specific suppressor T cells on the amplified anticryptococcal delayed-type hypersensitivity response. 下载免费PDF全文
Cell-mediated immunity is an important host resistance mechanism against Cryptococcus neoformans, the etiological agent of cryptococcosis. Previous studies from our laboratory have shown that the anticryptococcal cell-mediated immune response as measured by delayed-type hypersensitivity (DTH) is down-regulated by a cascade of antigen-specific T suppressor (Ts) cells. Recently, we have identified a population of CD4 T cells that up-regulate the anticryptococcal DTH response (Tamp cells). The Tamp cells are found in the spleens of donor mice at 6 days after immunization with cryptococcal antigen, and they amplify the anticryptococcal DTH response when transferred to syngeneic recipients at the time of immunization of the recipients. In this study, we determined the effects of C. neoformans-specific Ts cells on the induction of the Tamp cells in the Tamp cell-donor mice and on the induction and expression of the amplified anticryptococcal DTH response in the Tamp cell-recipient mice. When cryptococcal-specific Ts1 cells were given at the time of immunization of the Tamp cell-donor mice, induction of Tamp cells was inhibited. In contrast, when Ts1 cells were given at the time of adoptive transfer of Tamp cells, the recipients displayed amplified DTH responses, indicating that Ts1 cells do not affect the Tamp cells' function once the Tamp cells have been produced. C. neoformans-specific Ts2 cells given at the time of either immunization or footpad challenge of the Tamp cell-recipient mice did not alter, to any measurable extent, the amplified DTH response. These results indicate that in addition to amplifying the anticryptococcal DTH response, Tamp cells may protect the anticryptococcal TDH cells from suppression by C. neoformans-specific Ts cells, much like contrasuppressor cells do in other systems. However, further characterization of the Tamp cells revealed that they are not adherent to Viscia villosa lectin, indicating that the anticryptococcal Tamp cells do not have this characteristic in common with contrasuppressor cells of other antigen systems. 相似文献
489.
Chlamydia trachomatis infection does not enhance local cellular immunity against concurrent Candida vaginal infection 下载免费PDF全文
Although Th1-type cell-mediated immunity (CMI) is the predominant host defense mechanism against mucosal Candida albicans infection, CMI against a vaginal C. albicans infection in mice is limited at the vaginal mucosa despite a strong Candida-specific Th1-type response in the draining lymph nodes. In contrast, Th1-type CMI is highly effective against an experimental Chlamydia trachomatis genital tract infection. This study demonstrated through two independent designs that a concurrent Candida and Chlamydia infection could not accelerate or modulate the anti-Candida CMI response. Together, these results suggest that host responses to these genital tract infections are independent and not influenced by the presence of the other. 相似文献
490.
Algorithmic Approach to High-Throughput Molecular Screening for Alpha Interferon-Resistant Genotypes in Hepatitis C Patients 总被引:4,自引:1,他引:4 下载免费PDF全文