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11.
Immunological effects of tumor vaccines: II. T cell responses directed against cellular antigens in the viral oncolysates 总被引:1,自引:0,他引:1
Peripheral blood mononuclear cells (PBMC) from patients with epithelial adenocarcinoma of the ovary treated in vivo with tumor vaccines administered as viral oncolysates (VO) exhibited significant proliferative responses in vitro to VO as well as to cellular oncolysates (CO). These responses were dependent on the concentration of VO or CO. VO consisted of lysates from the same ovarian tumor cell lines 2774 and CaOV3 infected in vitro with the avirulent strain of influenza virus A/PR8/34. CO were lysates from the same ovarian tumor cell lines without virus. Depletion experiments with the OKT3 monoclonal antibody plus complement demonstrated that these proliferative responses are T cell specific and under the control of the HLA-D region. Furthermore, these T cell responses are directed against both tumor tumor cellular components and tumor HLA class I molecules. These responses can be detected as early as two weeks after the first intraperitoneal injection of VO and reach a maximum 12-16 weeks after the first application of VO for treatment. PBMC from ovarian patients that received in vivo VO exhibited insignificant proliferative responses to CO prepared from human fibroblasts or tumor cell lines of hematopoietic origin. In contrast, they exhibited significant proliferative responses to CO prepared from a human cervix tumor cell line. These results demonstrate systemic T cell activation by antigens in the tumor vaccines in patients with epithelial ovarian carcinoma after in vivo intraperitoneal administration of VO. 相似文献
12.
Review article: the use of biotherapeutic agents in the prevention and treatment of gastrointestinal disease 总被引:1,自引:1,他引:0
There is presently a lack of well conducted clinical trials demonstrating any significant benefits of probiotics in humans. With the exception of diarrhoea due to rotavirus infection in children there is little evidence from randomized, double-blind, placebo-controlled studies that bacterial probiotics have a significant beneficial action in preventing diarrhoea of any cause. The yeast Saccharomyces boulardii has been shown to be of benefit in the prevention of antibiotic-associated diarrhoea but not in preventing infection with Clostridium difficile . S. boulardii may also be of benefit in preventing relapse of C. difficile infection. Because of the simplicity of in vitro systems and some animal models, beneficial characteristics of probiotics such as the ability of bacteria to bind to epithelial surfaces are not always transferable to humans. Thus any postulated benefit from consumption of probiotic bacteria should only be accepted as fact after testing in clinical studies.
This review outlines our present knowledge of the mode of action of probiotics and presents the data from clinical trials on their use. 相似文献
This review outlines our present knowledge of the mode of action of probiotics and presents the data from clinical trials on their use. 相似文献
13.
14.
Detection of wheat gliadin contamination of gluten-free foods by a monoclonal antibody dot immunobinding assay 总被引:1,自引:0,他引:1
A R Freedman G Galfre E Gal H J Ellis P J Ciclitira 《Clinica chimica acta; international journal of clinical chemistry》1987,166(2-3):323-328
Unfractionated wheat gliadin was used to produce murine monoclonal antibodies to gliadin. A dot immunobinding assay, using these antibodies, was developed to detect possible gliadin contamination of nominally gluten-free flour, using dilute ethanol extracts spotted onto nitrocellulose membranes. The sensitivity of the assay was less than 10 micrograms/ml of unfractionated gliadin which permitted the detection of trace amounts of gliadin present in certain wheat starch based 'gluten-free' products. The assay detected not only wheat gliadin, but also prolamine extracts of rye, barley and oats; maize, soya and potato extracts as well as the control proteins casein and ovalbumin, gave negative results. The assay is of value as a simple and rapid method of screening foods for their suitability for consumption by patients with coeliac disease. 相似文献
15.
M S Freedman R D Macdonald 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》1987,14(3):312-314
Herpes zoster ophthalmicus can be complicated by a delayed ipsilateral cerebral angiitis which may cause infarction and a smoldering meningoencephalitis. We describe such a case treated successfully with steroids and acyclovir. It is important to consider the diagnosis of this disorder early since therapeutic intervention may prevent an otherwise high morbidity and mortality. Steroids may have to be continued for some time after clinical resolution, using the ESR as a guideline for decreasing dosages. 相似文献
16.
Quinine potently blocks single K+ channels activated by dopamine D-2 receptors in rat corpus striatum neurons 总被引:2,自引:0,他引:2
In single channel recordings from acutely dissociated neurons of the rat corpus striatum, a membrane K+ channel which is activated by dopamine D-2 receptors was blocked by nanomolar concentrations of quinine. An intermittent partial blockade was observed at 4-10 nM quinine, with a voltage dependence consistent with quinine binding to the channel near the extracellular surface of the membrane. A nearly complete blockade of channel current was observed at 100 nM quinine and above. Such concentrations are known to be too low to block various other ion channels, and may be attained in human brain at antimalarial dosages of quinine. Blockade of this channel by quinine may provide a useful experimental probe of dopaminergic function, as an alternative to D-2 receptor binding site blockade by neuroleptics. 相似文献
17.
Theodore Colton Laurence Freedman Tony Johnson David MaChin 《Statistics in medicine》1989,8(6):639-639
18.
K. P. Burdon C. D. Langefeld L. E. Wagenknecht J. J. Carr B. I. Freedman D. Herrington D. W. Bowden 《Diabetic medicine》2006,23(3):228-234
Aims Cardiovascular disease (CVD) is a major complication of Type 2 diabetes mellitus. The renin‐angiotensin system (RAS) and nitric oxide production are both important regulators of vascular function and blood pressure. Genes encoding proteins involved in these pathways are candidates for a contribution to CVD in diabetic patients. We have investigated variants of the angiotensinogen (AGT), angiotensin converting enzyme (ACE), angiotensin type 1 receptor (AT1R) and endothelial nitric oxide synthase (NOS3) genes for association with subclinical measures of CVD in families with Type 2 diabetes mellitus (T2DM). Methods Atherosclerosis was measured by carotid intima‐media thickness and calcification of the carotid and coronary arteries in 620 European Americans and 117 African Americans in the Diabetes Heart Study. Because of the role of these systems in blood pressure regulation, blood pressure was also investigated. Results Compelling evidence of association was not detected with any of the SNPs with any outcome measures after adjustments for covariates despite sufficient power to detect relatively small differences in traits for specific genotype combinations. Conclusions Genetic variation of the RAS and NOS3 genes do not appear to strongly influence subclinical cardiovascular disease or blood pressure in this diabetic population. 相似文献
19.
AM Manganoni† C Farisoglio† G Tucci† F Facchetti‡ PG Calzavara Pinton† 《Journal of the European Academy of Dermatology and Venereology》2007,21(10):1333-1336
BACKGROUND: Development of more than one primary melanoma in a patient is a relatively uncommon but well-recognized phenomenon. Its frequency has ranged from 1.2% to 8.2% in several series. This subgroup of patients with multiple primary lesions has not been characterized sufficiently. We report the experience of the Melanoma Unit of University Hospital Spedali Civili of Brescia, Italy. METHOD: Study subjects were drawn from 1240 patients with histologically confirmed melanoma, including melanoma in situ. From this group, multiple melanomas developed in 47 patients (3.79%). Every one of our patients has been taught to perform self-examination of the skin to detect suspicious pigmented lesions. RESULTS: Of the 47 patients described in this study, 38 had two primary melanomas, 7 had three melanomas and 2 had 5 and 10 melanomas, respectively. Mean age at first diagnosis was 46.2 years. The majority of subsequent melanomas (74.5%) were removed within 5 years of the initial operation. Synchronous lesions were found in 10 patients. In male patients, the lesion appeared most frequently on the trunk; in female patients, melanoma appeared mostly on the lower extremities. The second primary melanomas developed in the same anatomic region from the first in 53.2% of our patients. The proportion of in situ to invasive melanomas was greater for the second melanomas compared with the first melanomas. Regarding invasive melanomas, the mean thickness of the first melanomas was 1.31 mm compared with 0.66 mm for the second ones. Dividing patients into two groups, of more and less than 50, it is highlighted that in older patients synchronous lesions appear more frequently (36.4% vs. 8.0%); the median time interval between sequential melanomas is longer (84 vs. 63.7 months); and the ratio between the primary and secondary melanoma mean thickness is lower (1.21 : 1.08 vs. 1.43 : 0.63 mm). CONCLUSIONS: The study confirms that second primary melanoma is usually thinner than the first lesion, and it is more common in the same region of the body as the initial melanoma. The highest risk for a second melanoma is during the first 5 years, but a much longer time interval of 28 years is possible. Continued medical follow-up with complete skin examinations seems prudent, but it is very important to promote self-skin evaluation in patients to detect not only metastases but also subsequent primary melanomas in their earliest phases. 相似文献
20.
Spontaneous EDTA-independent cold platelet agglutination is a rare phenomenon that produces pseudothrombocytopenia when blood samples are analyzed in automated cell counters. We report a case of platelet cold agglutinins and an analysis by flow cytometry. A 49 year old woman presented with abnormal vaginal bleed secondary to uterine fibroids. Platelet clumping was observed in blood samples taken in EDTA-, heparin- and citrate-containing tubes. In flow cytometric tests, patient serum agglutinated 16% of normal platelets at 22 degrees C, and 7% of platelets after incubation at 37 degrees C; in contrast, 3% and < 1% of platelets were agglutinated at 22 and 37 degrees C, respectively, after incubation with normal serum. Minimal agglutination (< 10%) was observed with patient serum at a titre of 1:5 or at temperatures > 30 degrees C. After incubation at 4 degrees C, IgM antibody and C3 were increased on the patient's platelets; no significant amount of IgM or C3 was detected on normal platelets. The specificity of the platelet cold agglutinin was determined by competitive inhibition by monoclonal anti-CD41(GPIIbIIIa). Before the addition of monoclonal antibody, patient's serum agglutinated 16% of normal platelets at 22 degrees C; after addition of anti-CD41 only 2% of the platelets were agglutinated. This blocking effect was not observed with anti-CD42. The patient's platelets functioned normally as determined by CD62 and CD63 expression in response to thrombin, normal platelet aggregation in response to collagen, ADP, and ristocetin, and a normal template bleeding time. In summary, platelet agglutination by a platelet cold agglutinin was quantitated by flow cytometry, the responsible antibody was characterized as a low titre IgM with minimal activity > 30 degrees C, and competitive binding studies supported the GPIIbIIIa complex as the binding site for the antibody. Since the antibody did not affect platelet function, we believe that these patients will not suffer complications from their platelet cold agglutinin, but it could pose a problem under circumstances such as cardiac surgery with hypothermia. 相似文献