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101.
Nair B Stapp J Stapp L Bugni L Van Dalfsen J Burns JL 《Journal of clinical microbiology》2002,40(8):2791-2794
The microscopic examination of Gram-stained sputum specimens is very helpful in the evaluation of patients with community-acquired pneumonia and has also been recommended for use in cystic fibrosis (CF) patients. This study was undertaken to evaluate that recommendation. One hundred one sputum samples from CF patients were cultured for gram-negative bacilli and examined by Gram staining for both sputum adequacy (using the quality [Q] score) and bacterial morphology. Subjective evaluation of adequacy was also performed and categorized. Based on Q score evaluation, 41% of the samples would have been rejected despite a subjective appearance of purulence. Only three of these rejected samples were culture negative for gram-negative CF pathogens. Correlation between culture results and quantitative Gram stain examination was also poor. These data suggest that subjective evaluation combined with comprehensive bacteriology is superior to Gram staining in identifying pathogens in CF sputum. 相似文献
102.
Mixed lymphocyte cultures were set up between blood mononuclear cells and irradiated autologous or allogeneic B lymphoblasts infected with Epstein-Barr virus. The resulting cytotoxic effector cells were cloned and tested for activity against the stimulating B lymphoblast, K562 and melanoma targets. Specific clones which killed only the stimulating B lymphoblasts (cytotoxic T lymphocytes; CTL) were re-cloned and the subclones tested for cytolysis of B lymphoblasts and melanoma cells. Of seven primary CTL clones generated in allogeneic culture, 308 subclones developed the ability to kill melanoma cells and none retained specific CTL function. In the autologous system, 180 subclones were derived from three specific primary clones: of these, 13 (7%) retained specific function, 29 (16%) were able to kill both B lymphoblasts and melanoma cells, and 93 (52%) killed only the melanoma target. Testing of random clones demonstrated that whereas both B lymphoblast killing (CTL function) and melanoma cell killing (anomalous killer; AK function) were blocked by a monoclonal antibody to LFA-1, only CTL function was blocked by anti-T3 or anti-T8 antibodies. The factor(s) causing the progression of CTL to AK cells are discussed. These data thus demonstrate that the majority of CTL are capable of mediating AK cell function and are thus potentially suitable for passive immunotherapy. 相似文献
103.
Activated lymphocyte killer cells derived from melanoma tissue or peripheral blood 总被引:1,自引:1,他引:1
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G F Burns M F Good C Riglar P F Bartlett R M Crapper I R Mackay 《Clinical and experimental immunology》1984,57(2):487-494
Lymphoid cells infiltrating metastatic melanomas were grown directly from cell suspensions of tumour tissue by the addition of T cell growth factor. Lymphoid cells grew out at the expense of tumour cells in six of seven freshly excised tumours, and cells from two cultures were expanded for in vitro testing of cytolytic function against different target cells. Early in culture the tumour derived lymphocytes killed fresh autologous melanoma cells and, particularly later in culture, were highly and non-specifically cytolytic for cultured melanoma and non-melanoma cells. Cultured peripheral blood lymphocytes from patients with melanoma, and from normal subjects, were cytolytic to the same degree as tumour derived lymphocytes, and also resembled cells grown from tumour tissue in possessing acid phosphatase activity which was resistant to tartrate. Cultured lymphoblasts from both tumour and peripheral blood had a T cell phenotype when analysed with monoclonal antibodies. An in vitro co-culture system was employed to study the kinetics and the precursors of these non-specific killer cells among blood mononuclear cells. Blood mononuclear cells cultured with irradiated B lymphoblasts led to the generation of non-specific cytolytic cells, referred to as activated lymphocyte killer (ALK) cells, after 7-10 days of culture and the progenitors of these ALK cells were demonstrated to be distinct from those of specific cytolytic T cells. 相似文献
104.
Immunization of mice with the B oligomer of pertussis toxin induced antibodies to the native toxin as measured by an enzyme-linked immunosorbent assay. These antibodies neutralized the ability of pertussis toxin to alter the morphology of Chinese hamster ovary cells. Furthermore, mice immunized with the B oligomer, when challenged with pertussis toxin, did not exhibit the leukocytosis normally associated with exposure to the toxin. These results demonstrate that the B oligomer, which does not contain the enzymatic activity of the holotoxin, can be used to induce a neutralizing antibody response and suggest that the B oligomer might be considered for use in acellular pertussis vaccines. 相似文献
105.
Differential expression of TGF-beta1 and TGF-beta3 in serosal tissues of human intraperitoneal organs and peritoneal adhesions 总被引:5,自引:0,他引:5
Chegini N Kotseos K Zhao Y Bennett B McLean FW Diamond MP Holmdahl L Burns J 《Human reproduction (Oxford, England)》2001,16(6):1291-1300
Elevated local expression of transforming growth factor (TGF-beta) has been associated with increased incidence of peritoneal adhesion formation. In this study we determine whether differences in basal expression of TGF-beta in serosal tissue of peritoneal organs correlate with incidence of adhesion formation. Serosal tissue of parietal peritoneum, uterus, oviduct, ovary, omentum, large and small bowels as well as adhesions, skin, fascia, subcutaneous tissue, peritoneal fluid and serum were collected from 57 subjects with/without adhesions who were undergoing abdominal/pelvic surgery. To determine TGF-beta1 and TGF-beta3 mRNA and protein expression, total RNA and protein were isolated from these tissues and along with the fluids, subjected to quantitative RT-PCR and enzyme-linked immunosorbent assay (ELISA) respectively. Tissue sections were immunostained for TGF-beta1 and TGF-beta3 protein. We found that TGF-beta1 and TGF-beta3 mRNA and protein are expressed in these tissues and present in peritoneal fluids and serum, with considerable variations in level of their expression. Comparatively, there was more variation in TGF-beta1 than TGF-beta3 expression without age or gender relation. Adhesions express a significantly higher TGF-beta1 mRNA and have the highest TGF-beta1:TGF-beta3 ratio, with lowest concentrations and ratio detected in omentum, small and large bowels; in contrast uterus expresses higher TGF-beta3, with lowest concentrations detected in subcutaneous tissue and large bowels (P < 0.05). A similar trend was also observed for total (active + latent) TGF-beta1 protein expression, with low active TGF-beta1 that was not significantly different among the tissue extracts and fluids. However, the lowest active:total TGF-beta1 ratio was found in adhesions and ovary. In subjects with adhesions, the adhesions express significantly more TGF-beta1 compared to parietal peritoneum (P < 0.05). Immunoreactive TGF-beta1 and TGF-beta3 protein were present in various cell types in these tissues with intensity reflecting their mRNA and protein expression. In conclusion, we provided evidence that serosal tissue of various peritoneal organs and adhesions express TGF-beta1 and TGF-beta3. Since TGF-beta is expressed differently in these tissues and tissue injury often alters the expression of TGF-beta, we propose that tissues with a higher basal expression of TGF-beta may become predisposed to develop more adhesions compared to others. 相似文献
106.
Serotypic and genotypic characterization of human serotype 10 rotaviruses from asymptomatic neonates. 总被引:2,自引:7,他引:2
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S J Dunn H B Greenberg R L Ward O Nakagomi J W Burns P T Vo K A Pax M Das K Gowda C D Rao 《Journal of clinical microbiology》1993,31(1):165-169
Human rotaviruses were isolated from asymptomatic neonates at various hospitals and clinics in the city of Bangalore, India, and were found to be subgroup I specific and possess long RNA patterns (M. Sukumaran, K. Gowda, P. P. Maiya, T. P. Srinivas, M. S. Kumar, S. Aijaz, R. R. Reddy, L. Padilla, H. B. Greenberg, and C. D. Rao, Arch. Virol. 126:239-251, 1992). Three of these strains were adapted to tissue culture and found by serotype analysis and neutralization assays to be of serotype 10, a serotype commonly found in cattle but infrequently found in humans and not previously identified in neonates. By RNA-RNA hybridization, a high level of relatedness to a serotype 10 bovine rotavirus strain and a low-to-medium level of relatedness to a human rotavirus strain were observed. Since this human isolate shares a genogroup with bovine rotavirus, it is likely that it originated by interspecies transmission. A human rotavirus strain isolated from asymptomatic neonates and similar to bovine rotavirus might represent a good vaccine candidate. 相似文献
107.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
108.
We review the clinical features and histopathologic changes observed in 69 cases of lymphadenopathy in homosexual men. The most common pattern seen was that of florid reactive follicular hyperplasia (43 cases). A peculiar and distinctive lysis of the germinal centers, a phenomenon we have termed "follicle lysis," was noted in 25 cases. Eighteen of these lymph nodes also contained sinusal collections of "monocytoid" cells and neutrophils and six showed focal dermatopathic changes. Seven cases were characterized by a lymphocyte-depleted pattern with only occasional regressively transformed germinal centers. Nine patients were found to have involvement of their lymph nodes by Kaposi's sarcoma; malignant lymphomas were encountered in 10 patients (eight with Hodgkin's disease and two with non-Hodgkin's lymphomas). Polykaryocytes (multinucleated giant cells) were observed in germinal centers or interfollicular areas within the lymph nodes of four patients. Limited clinical follow-up was available but the lymphocyte-depleted group appeared to have a more aggressive clinical course (three patients in this group developed pneumocystis pneumonia, two had mycobacterial infections and one cutaneous Kaposi's sarcoma). The diverse nature of these findings and the potential for treatment of certain patients (i.e., those with malignant lymphomas and mycobacterial infections) underlines the importance of lymph node biopsy in all cases of unexplained lymphadenopathy in homosexuals and other individuals susceptible to the acquired immunodeficiency syndrome (AIDS). The histopathologic findings may also serve to identify a subgroup of these patients at increased risk to develop more severe AIDS-related complications. 相似文献
109.
The contributions of changes in cognitions (degree of belief in automatic thoughts) and the patient's relationship with his therapist to mood changes occurring during sessions of cognitive therapy were examined in data collected from 17 depressed and anxious patients. Results showed that both changes in automatic thoughts and the patient's relationship with his therapist made independent, additive contributions to mood changes. In addition, two patient characteristics (initial degree of belief in automatic thoughts and diagnosis) made significant unique contributions to mood changes. The stronger the patient's initial belief in his automatic thoughts, the smaller the mood change occurring in the session. Smaller mood changes also occurred in patients with a personality disorder diagnosis. These results suggest that mood changes in cognitive therapy sessions are a function of three types of factors: technical cognitive therapy interventions, the patient's relationship with his/her therapist, and patient characteristics. A multiple regression model with independent variables measuring these factors accounted for 89% of the variance in mood change in the session.We thank our patients for their generous contributions. Anna Rose Childress and Juli Kinchla contributed to the inception of the study. We thank Jeffrey M. Perloff for advice concerning the statistical analysis. Jonathan Baron, Susan Krantz, Ricardo Muõz, S. Lloyd Williams, and the anonymous reviewers gave helpful comments on an earlier draft. This paper was presented at a meeting of the Society for Psychotherapy Research, Lake Louise, Canada, June 1984. 相似文献
110.
C M Burns 《Canadian journal of surgery》1984,27(5):461-463
Immediate surgery is essential to resuscitate and save 5% to 10% of those suffering life-threatening trauma. Recently, emergency room surgery has been proposed as the procedure to follow in stabilizing such patients. Over a 3-year period, 41 moribund patients were treated by the trauma service at the Health Sciences Centre in Winnipeg. All were managed in the main operating theatre following a "crash protocol" for immediate surgery. Twenty-three patients arrived in cardiac arrest or with an unrecordable blood pressure; of these, 4 (17%) survived. Eighteen patients had a blood pressure of 70 mm Hg systolic or less and failed to respond to massive O positive blood transfusion; of these, 14 (77%) survived. The mix of mode of injury and injury severity scoring is important to compare results from within and between centres. The author's experience indicates that the use of a high-priority crash protocol for managing moribund patients with life-threatening traumatic injury in the main operating room provides a standard of care equal to or better than that reported for emergency room surgery. 相似文献