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71.
Human phagocytic cell responses to Scedosporium apiospermum (Pseudallescheria boydii): variable susceptibility to oxidative injury 下载免费PDF全文
Gil-Lamaignere C Roilides E Lyman CA Simitsopoulou M Stergiopoulou T Maloukou A Walsh TJ 《Infection and immunity》2003,71(11):6472-6478
Scedosporium apiospermum (Pseudallescheria boydii) is an emerging opportunistic filamentous fungus that causes serious infections in both immunocompetent and immunocompromised patients. To gain insight into the immunopathogenesis of infections due to S. apiospermum, the antifungal activities of human polymorphonuclear leukocytes (PMNs), mononuclear leukocytes (MNCs), and monocyte-derived macrophages (MDMs) against two clinical isolates of S. apiospermum were evaluated. Isolate SA54A was amphotericin B resistant and was the cause of a fatal disseminated infection. Isolate SA1216 (cultured from a successfully treated localized subcutaneous infection) was susceptible to amphotericin B. MDMs exhibited similar phagocytic activities against conidia of both isolates. However, PMNs and MNCs responded differently to the hyphae of these two isolates. Serum opsonization of hyphae resulted in a higher level of superoxide anion (O(2)(-)) release by PMNs in response to SA54A (amphotericin B resistant) than that seen in response to SA1216 (amphotericin B susceptible; P < 0.001). Despite this increased O(2)(-) production, PMNs and MNCs induced less hyphal damage to SA54A than to SA1216 (P < 0.001). To investigate the potential mechanisms responsible for these differences, hyphal damage was evaluated in the presence of antifungal oxidative metabolites as well as in the presence of a series of inhibitors and scavengers of antifungal PMN function. Mannose, catalase, superoxide dismutase, dimethyl sulfoxide, and heparin had no effect on PMN-induced hyphal damage to either of the two isolates. However, azide, which inhibits PMN myeloperoxidase activity, significantly reduced hyphal damage to SA1216 (P < 0.01) but not to SA54A. Hyphae of SA1216 were slightly more susceptible to oxidative pathway products, particularly HOCl, than those of SA54A. Thus, S. apiospermum is susceptible to antifungal phagocytic function to various degrees. The selective inhibitory pattern of azide with respect to hyphal damage and the parallel susceptibility to HOCl suggests an important difference in susceptibilities to myeloperoxidase products that may be related to the various levels of pathogenicity and amphotericin B resistance of S. apiospermum. 相似文献
72.
Effects of postmenopausal estrogen replacement on the concentrations and metabolism of plasma lipoproteins 总被引:23,自引:0,他引:23
B W Walsh I Schiff B Rosner L Greenberg V Ravnikar F M Sacks 《The New England journal of medicine》1991,325(17):1196-1204
BACKGROUND. Postmenopausal estrogen-replacement therapy may reduce the risk of cardiovascular disease, and this beneficial effect may be mediated in part by favorable changes in plasma lipid levels. However, the effects on plasma lipoprotein levels of postmenopausal estrogens in the low doses currently used have not been precisely quantified, and the mechanism of these effects is unknown. METHODS. We conducted two randomized, double-blind crossover studies in healthy postmenopausal women who had normal lipid values at base line. In study 1, 31 women received placebo and conjugated estrogens at two doses (0.625 mg and 1.25 mg per day), each treatment for three months. In study 2, nine women received placebo, oral micronized estradiol (2 mg per day), and transdermal estradiol (0.1 mg twice a week), each treatment for six weeks. The metabolism of very-low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) was measured by endogenously labeling their protein component, apolipoprotein B. RESULTS. In study 1, the conjugated estrogens at doses of 0.625 mg per day and 1.25 mg per day decreased the mean LDL cholesterol level by 15 percent (95 percent confidence interval, 11 to 19 percent; P less than 0.0001) and 19 percent (95 percent confidence interval, 15 to 23 percent; P less than 0.0001), respectively; increased the HDL cholesterol level by 16 percent (95 percent confidence interval, 12 to 20 percent; P less than 0.0001) and 18 percent (95 percent confidence interval, 14 to 22 percent; P less than 0.0001), respectively; and increased VLDL triglyceride levels by 24 percent (95 percent confidence interval, 8 to 40 percent; P less than 0.003) and 42 percent (95 percent confidence interval, 26 to 58 percent; P less than 0.0001), respectively. In study 2, oral estradiol increased the mean concentration of large VLDL apolipoprotein B by 30 +/- 10 percent (P = 0.05) by increasing its production rate by 82 +/- 18 percent (P less than 0.01). Most of this additional large VLDL was cleared directly from the circulation and was not converted to small VLDL or LDL. Oral estradiol reduced LDL cholesterol concentrations by 14 +/- 3 percent (P less than 0.005), because LDL catabolism increased by 36 +/- 7 percent (P less than 0.005). The oral estradiol increased the HDL cholesterol level by 15 +/- 2 percent (P less than 0.0001). Transdermal estradiol had no effect. CONCLUSIONS. The postmenopausal use of oral estrogens in low doses favorably alters LDL and HDL levels that may protect women against atherosclerosis, while minimizing potentially adverse effects on triglyceride levels. The decrease in LDL levels results from accelerated LDL catabolism; the increase in triglyceride levels results from increased production of large, triglyceride-rich VLDL. 相似文献
73.
74.
Isolation and characterization of cell surface mutants of Candida albicans. 总被引:3,自引:8,他引:3 下载免费PDF全文
W L Whelan J M Delga E Wadsworth T J Walsh K J Kwon-Chung R Calderone P N Lipke 《Infection and immunity》1990,58(6):1552-1557
Mutant strains of Candida albicans were obtained by selecting for cells that escaped agglutination by a polyclonal antiserum raised against standard C. albicans serotype A isolate B311. Mutants were obtained from strains B311 and B792 and from four strains isolated from patients with acquired immunodeficiency syndrome. All 15 tested mutants retained characteristic sugar assimilation patterns. All but one of the mutants retained the ability to form germ tubes and chlamydospores. Two mutants from an acquired immunodeficiency syndrome-derived isolate were deficient in binding complement ligands iC3b and C3d, whereas another mutant was deficient in binding ligand iC3b but not C3d. The hyphae of these three mutants lacked antigens when examined by Western immunoblotting with monoclonal antibody Ca-A, which detects several glycoproteins, including C3d-binding proteins. One of the complement-binding-deficient mutants was tested for its ability to colonize the gastrointestinal tract of rabbits but did not differ from the wild-type parent in site or degree of colonization. The proton magnetic resonance spectra of bulk mannan carbohydrate extracted from tested mutants showed the loss of a signal characteristic of the mannosyl alpha-PO4 linkage; each mutant also had a distinct pattern of other changes. 相似文献
75.
Bulimia and depression 总被引:2,自引:0,他引:2
In recent years several lines of evidence have emerged suggesting that eating disorders in general, and bulimia in particular, are in some way linked to affective illness. However, there are few data on the frequency of affective syndromes among patients who have anorexia nervosa or bulimia. This report describes the results of semistructured interviews using the Schedule for Affective Disorders and Schizophrenia (SADS) to evaluate the frequency of the current and lifetime diagnoses of affective illness among 50 female patients meeting DSM-III criteria for bulimia. Seventy percent of the patients had, at some time during their lives, met Research Diagnostic Criteria (RDC) for an episode of major depression and 88% had met RDC at some time during their lives for some affective disturbance. The implications of this high frequency of affective disturbance among patients with bulimia are discussed. 相似文献
76.
Laura McGillis Nimish Mittal Daniel Santa Mina Joyce So Medha Soowamber Aliza Weinrib Leslie Soever Dmitry Rozenberg Louis Liu Yvonne Tse Joel Katz George S Charames Kieran Murphy Peter Vadas Maxwell P Slepian Scott Walsh Lindsay Wilson Arnon Adler Alyssa Franzese Laura Hussey Dayna‐Lynn Nevay Juan Guzman Hance Clarke 《American journal of medical genetics. Part A》2020,182(3):484-492
The new 2017 diagnostic criteria for hypermobile Ehlers–Danlos Syndrome (hEDS) provide a framework for diagnosing hEDS but are more stringent than the previous Villefranche criteria. Our clinical experience at the GoodHope EDS clinic was that the 2017 criteria left many highly symptomatic patients without a diagnosis of hEDS. We conducted a retrospective cohort study to confirm our clinic experience and assess the accuracy of the 2017 diagnostic criteria for hEDS in patients who had a previous hEDS diagnosis based on the Villefranche criteria. Our study found that 15% (n = 20 of 131) of patients with a prior diagnosis of hEDS met the 2017 diagnostic criteria, and many of the traits used to distinguish hEDS were not significantly more frequent in patients who met 2017 criteria versus those who did not. In both groups objective systemic manifestations were found less frequently than subjective systemic manifestations. Beighton score (BS) as assessed by primary care practitioner was found to be higher than assessment by EDS practitioner in 81% (n = 74 of 91) of cases. Generalized joint hypermobility was confirmed in only 46% (n = 51 of 111) of patients who had a previous diagnosis of hEDS. Higher BS did not correlate with increased number of systemic manifestations in our cohort. Common comorbidities of hEDS were found with similar frequency in those who met 2017 criteria and those who did not. Based on our cohort, the 2017 hEDS diagnostic criteria require refinement to improve its diagnostic accuracy. 相似文献
77.
M D Rifkin E A Zerhouni C A Gatsonis L E Quint D M Paushter J I Epstein U Hamper P C Walsh B J McNeil 《The New England journal of medicine》1990,323(10):621-626
BACKGROUND. In 1987, a cooperative study group consisting of five institutions was formed to determine the relative benefits of magnetic resonance imaging (MRI) and endorectal (transrectal) ultrasonography in evaluating patients with clinically localized prostate cancer (stage Ta or Tb). METHODS. Over a period of 15 months, 230 patients were entered into the study and evaluated with identical imaging techniques. We compared imaging results with information obtained at the time of surgery and on pathological analysis. RESULTS. MRI correctly staged 77 percent of cases of advanced disease and 57 percent of cases of localized disease; the corresponding figures for ultrasonography were 66 and 46 percent (P not significant). These figures did not vary significantly between readers; moreover, simultaneous interpretation of MRI and ultrasound scans did not improve accuracy. In terms of detecting and localizing lesions, MRI identified only 60 percent of all malignant tumors measuring more than 5 mm on pathological analysis and ultrasonography identified only 59 percent. CONCLUSIONS. The MRI and ultrasonography equipment that is currently available is not highly accurate in staging early prostate cancer, mainly because neither technique has the ability to identify microscopic spread of disease. Further evaluation with improved equipment may improve the accuracy of these techniques. 相似文献
78.
Surgery in the treatment of varicose veins 总被引:1,自引:0,他引:1
To identify variables which might influence the results of varicose vein surgery, a ten-year retrospective study was carried out on 612 patients undergoing varicose vein surgery. Patient symptomatology, type of venous insufficiency and operator experience were examined and correlated with the results of surgery. The female-to-male ratio was 2:1. The mean age was 47 years for women, 45 years for men. A family history of varicose veins was recorded in 74% of patients. A history of previous deep venous thrombosis was reported in 5% of cases, but in the sub-group of patients with stasis ulceration, the incidence was 9%. Cosmetic appearance was the commonest presenting complaint (54%), while ulceration was relatively infrequent (14%). There was moderate-to-marked improvement in 86% of cases at one year. This was sustained in 79% at three years, in 75% at five years and in 74% at ten years. There was no correlation between the type of venous insufficiency or the presenting complaint, and the result of surgery. Operator experience had the most significant effect on the outcome of surgery (P less than 0.001). Our findings indicate that varicose vein surgery offers most patients a satisfactory result. The only significant variable was operator experience. We strongly recommend closer supervision of junior staff performing this type of surgery, particularly as a large proportion of these patients (25% in this study) are operated on by the more junior staff. 相似文献
79.
D Dao C P Walsh L Yuan D Gorelov L Feng T Hensle P Nisen D J Yamashiro T H Bestor B Tycko 《Human molecular genetics》1999,8(7):1337-1352
80.
Effect of age and preexisting antibody on serum antibody response of infants and children to the F and G glycoproteins during respiratory syncytial virus infection. 总被引:8,自引:3,他引:8 下载免费PDF全文
B R Murphy D W Alling M H Snyder E E Walsh G A Prince R M Chanock V G Hemming W J Rodriguez H W Kim B S Graham et al. 《Journal of clinical microbiology》1986,24(5):894-898
The serum antibody response of 50 infants and children infected with respiratory syncytial virus (RSV) was determined by a glycoprotein-specific enzyme-linked immunosorbent assay, and the effects of age and preexisting antibody titer at the time of RSV infection on response to the G and F glycoproteins of RSV were examined. The immune response to the G and F glycoproteins was assessed with anti-human immunoglobulin A to permit measurement of the response of young infants in the presence of maternally derived immunoglobulin G. The findings suggested that age primarily affects the response to the F glycoprotein and that preexisting antibody titer affects the response to the G glycoprotein. 相似文献