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51.
Francisella tularensis is a highly infectious gram-negative bacterium with potential for use as a bioweapon. Analysis of the F. tularensis live vaccine strain (LVS) ultrastructure by electron microscopy revealed the presence of long, thin fibers, similar in appearance to type 4 pili. The highly virulent F. tularensis Schu S4 strain was found to contain type 4 pilus genes, and we confirmed that these genes are present and expressed in the LVS. 相似文献
52.
Gil KM Carson JW Porter LS Ready J Valrie C Redding-Lallinger R Daeschner C 《Journal of pediatric psychology》2003,28(5):363-373
OBJECTIVE: To determine the extent to which daily stress and mood are associated with pain, health-care use, and school activity in adolescents with sickle cell disease (SCD). METHOD: Adolescents with SCD (n = 37; aged 13 to 17 years) completed daily diaries assessing pain, stress, mood, activity, and health-care use for up to 6 months. Multilevel modeling was used to analyze the data. RESULTS: Daily increases in stress and negative mood were associated with increases in same-day pain, health-care use, and reductions in school and social activity. Increases in positive mood were associated with decreases in pain, less health-care use, and more activity participation. Notably, pain was predictive of higher stress and lower positive mood on subsequent days. CONCLUSION: Pain in adolescents with SCD is stressful and may lead to alterations in mood states. Understanding the way in which these variables relate to health-care use and activity may lead to improved pain management approaches. 相似文献
53.
54.
Identification of wall-specific antigens synthesized during germ tube formation by Candida albicans. 总被引:5,自引:25,他引:5
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Walls of the two cellular forms (blastoconidia and mycelia) of Candida albicans ATCC 26555 were obtained from cells metabolically labeled (6-h pulse) with 14C-protein hydrolysate and [3H]threonine. Walls were purified by thorough washings with buffered and sodium dodecyl sulfate solutions and digested with Zymolyase 20T. The enzymatic treatment released four major high-molecular-weight mannoproteins (HMWM), with apparent molecular masses of 650, 500, 340, and 200 kilodaltons (HMWM-650, HMWM-500, HMWM-340, and HMWM-200, respectively), from yeast cells, whereas two high-molecular-mass mannoproteins (HMWM-260 and HMWM-180) were solubilized from mycelial cells. Some additional minor low-molecular-weight species were also detected in the enzymatic digests of walls from both types of cell. Single and dual pulse-chase experiments indicated that the HMWM-260 and HMWM-180 species reflect de novo synthesis of new proteins specific for the mycelia and do not represent a topological rearrangement of blastoconidium wall components. Monoclonal antibodies were raised against the HMWM-260 species (quantitatively the predominant component in the mycelial walls), and polyclonal rabbit antibodies were obtained against yeast or mycelial cell walls. Anti-mycelial cell wall polyclonal antibodies were adsorbed to whole killed blastoconidia to remove antibodies against common blastoconidium and mycelial wall antigens. Titration by enzyme-linked immunosorbent assay revealed that the monoclonal antibodies could recognize an epitope of the protein moiety of the HMWM-260 mannoprotein. Immunoblotting and immunofluorescence techniques using these monoclonal and polyclonal antibodies confirmed that the HMWM-260 and HMWM-180 species are specific components of the envelope of the mycelial cell walls. 相似文献
55.
Detection of the apoptosis-suppressing oncoprotein bc1-2 in hormone-refractory human prostate cancers. 总被引:7,自引:10,他引:7
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M. Colombel F. Symmans S. Gil K. M. O'Toole D. Chopin M. Benson C. A. Olsson S. Korsmeyer R. Buttyan 《The American journal of pathology》1993,143(2):390-400
The oncoprotein encoded by bc1-2 is unique because of its intracellular location (a mitochondrial membrane protein) and apparent mode of action (suppression of apoptosis). To date, this oncogene has been associated only with the development of certain forms of human B-cell lymphoma. In this report, we describe our experience with a monoclonal antibody made against a synthetic peptide for bc1-2 that can recognize the bc1-2 protein and identify cells in human prostate glands expressing this proto-oncogene with in situ immunohistochemical procedures. These procedures were utilized to survey a series of 62 human tissues to evaluate whether bc1-2 might have a role in the developing prostate gland or in prostate oncogenesis. While all primordial epithelial cells in a fetal prostate gland immunostain for bc1-2, normal and hypertrophic prostate glands of the adult show bc1-2 expression restricted to the basal cells. All epithelial cells in areas of prostatic intraepithelial neoplasia were stained by this antibody, as were most (62%) localized invasive prostatic carcinomas. In contrast, all primary prostatic carcinomas and metastases obtained from metastatic prostate cancer patients after hormone treatment (hormone-refractory tumors) stained positive for bc1-2. This study demonstrates that the oncoprotein encoded by bc1-2 can be detected at sequential stages in the natural history of human prostate cancer. Since the bc1-2 oncoprotein is known to suppress the cellular response to apoptotic stimuli, it will be important to determine whether bc1-2 expression is a factor in the development of prostate cancers and in the survival of hormone-refractory prostate cancer cells. 相似文献
56.
Oral administration of muscle derived small molecules inhibits tumor spread while promoting normal cell growth in mice 总被引:5,自引:0,他引:5
Bar-Yehuda S Farbstein T Barer F Ohana G Fishman P 《Clinical & experimental metastasis》1999,17(6):531-535
Tumor metastases are extremely rare in striated muscles. This is surprising given the fact that this tissue constitutes 60%
of body weight. The present study focuses on small molecules produced and secreted by muscle cells which possess anti-cancer
activity in vivo. Recently we have shown that a low molecular weight fraction (<1000 Dalton) of skeletal muscle cell conditioned medium (muscle
factor-MF), markedly inhibits the proliferation of carcinoma, sarcoma or melanoma cell lines in vitro. The MF exerts a cytostatic effect on tumor cell growth and arrests the cells in the G0/G1 of the cell cycle. However, normal
cell proliferation, such as bone marrow and fibroblasts, was stimulated following incubation with MF. In this study, the effect
of orally administered MF on melanoma and sarcoma growth was examined in mice. The administration of MF to mice inoculated
intravenously with melanoma (B16–F10) or sarcoma (MCA-105) cells, resulted in a statistically significant inhibition of metastatic
lung foci. In a different model, melanoma was induced in the foot pad and after development of a local lesion, the leg was
amputated. A prolonged survival time was observed in the MF treated groups. Since the MF stimulated bone marrow cell proliferation
in vitro, we decided to test its efficacy as an inhibitor of the myelotoxic effect exerted by chemotherapy, in vivo. MF, administered after chemotherapy, restored the number of white blood cells and yielded an increased percentage of neutrophils
compared with the decline in these parameters after administration of chemotherapy alone. Thus, it is indicated that MF exerted
a systemic anti tumor and chemoprotective effect when given orally. It can be concluded that it is bioavailable and is not
biodegradable in the digestive system. MF may be considered as a potential therapy for the prevention of tumor spread.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
57.
Life expectancy in British Marfan syndrome populations 总被引:2,自引:0,他引:2
JR Gray AB Bridges RR West L. McLeish AG Stuart JCS Dean MEM Porteous M. Boxer SJ Davies 《Clinical genetics》1998,54(2):124-128
A total of 206 patients with Marfan syndrome were ascertained throughout genetic clinics in Wales and Scotland during the period 1970–1990. There were 45 deaths representing 22% of the cohort. Mean age at death was 45.3 ± 16.5 years. 50% median cumulative survival in the total cohort (n = 206) was 53 years for males and 72 years for females. Multivariate analysis confirmed severity as the best independent indicator of survival. These findings and survival curves will assist in the counselling of British families and individuals with Marfan syndrome. 相似文献
58.
Nicole Fellmann Mario Bedu Gil Boudet Martine Mage Marcel Sagnol Jean-Marc Pequignot Bruno Claustrat Jocelyne Brun Liliane Peyrin Jean Coudert 《European journal of applied physiology》1992,64(3):258-265
Summary The aim of the study was to investigate the inter-relationships between pituitary-adrenal hormones and catecholamines during a prolonged competition over 6 days. Plasma adrenocorticotropic hormone (ACTH), cortisol (C), -endorphin (EP), free and sulphated adrenaline (A) and noradrenaline (NA) were measured in 11 volunteer male subjects during a national Nordic-ski race (323 km). Blood samples were obtained before the competition in the evening as control (D0), and before and after each day's racing (D1–D6). The mean daily heart rate (f
c) was calculated fromf
c values recorded every minute during the race. The results showed the following: changes in meanf
c [from 147 (SEM 3) to 156 (SEM 3) beats · min–1 according to the day] were not significant during the race. Diurnal variations in ACTH, EP and C were no longer apparent after the race: evening levels were higher than their respective D0 values during the race, except on D3 when there was a lack of response to exercise in the three hormones. Unlike ACTH and EP, pre- and postexercise C values on D1 and D2 were higher than those on the subsequent days (P<0.001). In contrast, there was a progressive accumulation of A and NA in pre-and postrace concentrations which reached a plateau in about 4 days. Positive correlations between exercise responses in ACTH, C and EP were found especially on D3 and D6 (P<0.001) but there were no significant correlations between catecholamines and the other three hormones. Thus, prolonged competition over 6 days evoked different control mechanisms for hormones of the pituitary-adrenal axis and catecholamines. A sustained catecholamine release and sympathetic activation induced a progressive NA and A accumulation during the race. In contrast, the lack of a response to exercise in ACTH, EP and C on D3 suggested a dissociated central command for pituitary axis hormones and sympathetic adrenal activation. On the following days, the response to a lack of exercise, in spite of ACTH stimulation, may have reflected an adaptation of adrenal glands to prolonged stress. 相似文献
59.
Gil LH Alves FP Zieler H Salcedo JM Durlacher RR Cunha RP Tada MS Camargo LM Camargo EP Pereira-da-Silva LH 《Journal of medical entomology》2003,40(5):636-641
Studies on seasonal anopheline fauna variation were performed in two distinct settlements in the State of Rond?nia, Brazil: one at the Madeira River banks (Portuchuelo) with stable native Amazonian population; the other at an inland lumber-extracting farm (Urupá) in dry land, in which adults are mostly migrants. During a 6-yr period (1994-2000), 8,638 adult anophelines were collected: 2,684 in Urupá and 5,954 in Portuchuelo. Anopheles darlingi represented >95% of total mosquitoes caught. Dissection of 4,424 A. darlingi females yielded a very low sporozoite infection index below 0.1%. Oocysts were found in both localities in approximately 0.1% of dissected mosquitoes. Determination of the hour biting rates disclosed seasonal variations in both localities. However, in Portuchuelo, mosquito density peaked at the acme of the rainy season, whereas at Urupá it peaked in the dry season. The increase in mosquito density and incidence of malaria cases were coincident. The high mosquito densities observed in the riverine settlement of Portochuelo sector B, which permits evaluation in > 10,000 mosquitoes' bites/person/year, could explain, in spite of the low mosquito's infection index, the previously described development of natural immunity in the local population that is not observed in the dry land agroindustrial settlement of Urupá. 相似文献
60.
J Gil 《Human pathology》1989,20(3):203-204