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71.
These studies examined the effect of the lymphokine interleukin-2 (IL-2) on porcine peripheral blood lymphocytes (PBL). Cultures of porcine (Yorkshire) PBL in human recombinant (r) IL-2 had a time-dependent increase in activation of killer cells. Previous reports of porcine killer cells derived from PBL indicated maximal lysis 18 hr after killer and target cells were mixed, with very little lytic activity at 4 hr. After culturing for 2 days in rIL-2, the cells acquire enhanced lytic capabilities resulting in substantial target lysis in the 4-hr assay. Enhanced lytic activity in the 18 hr assay occurs as early as 30 min after exposure to rIL-2, with a more significant increase after 2 days' exposure. The IL-2-treated cells have an increase in the incorporation of tritiated thymidine and an increase in percentage of granular cells. Tumour targets, such as Daudi, which are resistant to lysis, and L929, Mdt4 and P815, which are moderately susceptible to lysis by untreated swine PBL, had a substantial increase in lysis in IL-2-treated swine PBL. These results indicate human rIL-2 induces functional and morphological changes in swine peripheral blood lymphocytes. 相似文献
72.
D. J. P. Ferguson A. A. McColm D. M. Ryan P. Acred 《Virchows Archiv : an international journal of pathology》1986,410(1):43-48
Summary The initial colonization, byStaphylococcus aureus, of the catheter damaged aortic valve and aorta of the rabbit, was examined by light and electron microscopy at 15 min, 3 h and 24 h post inoculation (PI). At 15 min PI, the majority of bacteria (80%) were located on the lateral surfaces of the thrombic vegetations while 20% were attached directly to the connective tissue of the aortic valve and aorta in areas where the endothelial lining was disrupted. By 3 h the bacteria on the thrombic vegetations were covered by fibrin. At this time, the bacteria both within the vegetations and on the surface of the vasculature were undergoing multiplication to form small groups. The precipitation of thrombus around the bacteria attached to the surface of the aorta to form microscopic infected vegetations had occurred by 24 h PI. The colonizing bacteria did not elicit any phagocytic response. The colonization of the cardiovasculature byStaph. aureus did not necessarily require pre-existing vegetations. 相似文献
73.
2-Hour cytomegalovirus pp65 antigenemia assay for rapid quantitation of cytomegalovirus in blood samples
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Of 109 blood samples tested for cytomegalovirus (CMV) antigenemia, 18 (16.5%) were positive. CMV Brite detected 13 and CMV Brite Turbo detected 16 of the 18 positives. There was no significant difference in the number of positive cells detected per sample. The seven discrepant samples contained a median of only one positive cell. 相似文献
74.
Staphylococcal exopolysaccharides inhibit lymphocyte proliferative responses by activation of monocyte prostaglandin production.
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The glycocalyx (exopolysaccharides) of Staphylococcus epidermidis has been reported to inhibit a variety of host defense mechanisms. We have examined the inhibitory effects of glycocalyx on the proliferation of human peripheral blood mononuclear cells (PBMC) and the mechanism of this inhibition. Glycocalyx isolated and partially purified under endotoxin-free conditions from defined liquid medium cultures of S. epidermidis and Staphylococcus lugdunensis inhibited the proliferative response of PBMC when added to cultures at 10 to 100 micrograms/ml. Glycocalyx-mediated inhibition of phytohemagglutinin-stimulated proliferation of PBMC required the presence of plastic-adherent peripheral blood monocytes. Culture supernatants of monocytes stimulated with glycocalyx contained a soluble factor that inhibited the proliferation of monocyte-depleted PBMC. This soluble inhibitory factor was not produced in the absence of glycocalyx or in the presence of both glycocalyx and indomethacin. Analysis of the supernatants of cultures of adherent monocytes revealed that glycocalyx from S. epidermidis and from S. lugdunensis could activate monocyte production of prostaglandin E2 (PGE2), human interleukin-1, and tumor necrosis factor alpha. The addition of purified PGE2, at the same levels of PGE2 (greater than or equal to 10(-9) M) generated in the monocyte cultures, to PBMC cultures resulted in a similar inhibition of proliferative responses. It is concluded that, contrary to previous suggestions, the bacterial glycocalyx does not have a direct inhibitory effect on T lymphocytes. However, it does appear that glycocalyx from coagulase-negative staphylococci can activate monocyte PGE2 production and that it is this activity that in turn contributes to the inhibition of T-cell proliferation. 相似文献
75.
M L Landry D Ferguson S Cohen K Huber P Wetherill 《Journal of clinical microbiology》1995,33(1):257-259
Blood samples held at either 4 degrees C or room temperature for 1 day had similar mean decreases in number of cytomegalovirus antigenemia-positive cells (52 to 55%) and similar false-negative test results (13 to 14%). After 2 days, samples held at 4 degrees C showed no further decline, whereas samples held at room temperature had a mean 81% decrease in positive cells, a 32% false-negative rate, and a more marked deterioration in cell morphology. 相似文献
76.
High rates of clustering of strains causing tuberculosis in Harare, Zimbabwe: a molecular epidemiological study
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Easterbrook PJ Gibson A Murad S Lamprecht D Ives N Ferguson A Lowe O Mason P Ndudzo A Taziwa A Makombe R Mbengeranwa L Sola C Rastogi N Rostogi N Drobniewski F 《Journal of clinical microbiology》2004,42(10):4536-4544
We examined the pattern of tuberculosis (TB) transmission (i.e., reactivation versus recent transmission) and the impact of human immunodeficiency virus (HIV) infection in Harare, Zimbabwe. Consecutive adult smear-positive pulmonary TB patients presenting to an urban hospital in Harare were enrolled. A detailed epidemiological questionnaire was completed, and tests for HIV type 1 and CD4 cell counts were performed for each patient. Molecular fingerprinting of the genomic DNA recovered from cultures of sputum was performed by two molecular typing methods: spacer oligonucleotide typing (spoligotyping) and analysis of variable number of tandem DNA repeats (VNTRs). A cluster was defined as isolates from two or more patients that shared the same spoligotype pattern or the same VNTR pattern, or both. DNA suitable for typing was recovered from 224 patients. The prevalence of HIV infection was 79%. Of 187 patient isolates (78.6%) typed by both spoligotyping and analysis of VNTRs, 147 were identified as part of a cluster by both methods. By spoligotyping alone, 84.1% of patient isolates were grouped into 20 clusters. The cluster size was generally <8 patient isolates, although three large clusters comprised 68, 25, and 23 patient isolates. A total of 89.4% of the patient isolates grouped into 12 clusters defined by analysis of VNTRs, with 2 large clusters consisting of 127 and 13 patient isolates, respectively. Thirty-six percent of patient isolates with a shared spoligotype and 17% with a shared VNTR pattern were geographically linked within Harare, but they were not linked on the basis of the patient's home district. In a multivariate analysis, there were no independent predictors of clustering, including HIV infection status. Comparison with the International Spoligotype database (Pasteur Institute, Pointe a Pitre, Guadeloupe) demonstrated that our three largest spoligotype clusters are well recognized and ubiquitous in Africa. In this epidemiologically well characterized urban population with a high prevalence of HIV infection, we identified a very high level of strain clustering, indicating substantial ongoing recent TB transmission. Geographic linkage could be detected in a proportion of these clusters. A small group of actively circulating strains accounted for most of the cases of TB transmission. 相似文献
77.
When an antigen is first presented via the gut, either priming or suppression of the systemic immune response may result. Many factors influence the outcome, including physico-chemical properties of the antigen. The aim of this study is to establish if wheat gliadin behaves as an oral immunogen or tolerogen. Mice reared on a gluten-free diet were fed gliadin, either as wheat flour in a standard rodent diet or as the purified molecule. Immune status (tolerant or sensitized) was then defined by measuring specific systemic immune responses after parenteral immunization of gliadin-fed and control mice. A single feed of 25 or 125 mg of purified gliadin resulted in a dose-dependent suppression of both cell-mediated and humoral immune responses. Similar oral tolerance was achieved by feeding mice with a gluten-containing diet for a week. Finally, mice reared on a normal, gluten-containing diet showed evidence of established oral tolerance, with significantly lower systemic immune response to gliadin than mice reared on gluten-free diet. These results indicate that gliadin is an effective oral tolerogen. In vivo studies on the immunogenicity of gliadins should be conducted in animals from gluten-free colonies. 相似文献
78.
Tyrer P Thompson S Schmidt U Jones V Knapp M Davidson K Catalan J Airlie J Baxter S Byford S Byrne G Cameron S Caplan R Cooper S Ferguson B Freeman C Frost S Godley J Greenshields J Henderson J Holden N Keech P Kim L Logan K Manley C MacLeod A Murphy R Patience L Ramsay L De Munroz S Scott J Seivewright H Sivakumar K Tata P Thornton S Ukoumunne OC Wessely S 《Psychological medicine》2003,33(6):969-976
BACKGROUND: We carried out a large randomized trial of a brief form of cognitive therapy, manual-assisted cognitive behaviour therapy (MACT) versus treatment as usual (TAU) for deliberate self-harm. METHOD: Patients presenting with recurrent deliberate self-harm in five centres were randomized to either MACT or (TAU) and followed up over 1 year. MACT patients received a booklet based on cognitive behaviour therapy (CBT) principles and were offered up to five plus two booster sessions of CBT from a therapist in the first 3 months of the study. Ratings of parasuicide risk, anxiety, depression, social functioning and global function, positive and negative thinking, and quality of life were measured at baseline and after 6 and 12 months. RESULTS: Four hundred and eighty patients were randomized. Sixty per cent of the MACT group had both the booklet and CBT sessions. There were seven suicides, five in the TAU group. The main outcome measure, the proportion of those repeating deliberate self-harm in the 12 months of the study, showed no significant difference between those treated with MACT (39%) and treatment as usual (46%) (OR 0.78, 95% CI 0.53 to 1.14, P=0.20). CONCLUSION: Brief cognitive behaviour therapy is of limited efficacy in reducing self-harm repetition, but the findings taken in conjunctin with the economic evaluation (Byford et al. 2003) indicate superiority of MACT over TAU in terms of cost and effectiveness combined. 相似文献
79.
Preimplantation genetic diagnosis principles and ethics 总被引:4,自引:0,他引:4
80.
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