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21.
T-cell mediated autoimmune beta-cell destruction is an important component of type 1 diabetes (T1D) and insulin is a critical antigen recognized by autoreactive T-cells. The aim of this study was to investigate the precursor frequency of insulin reactive T-cells in type 1 diabetes. We studied 19 T1D patients, 12 age-matching non-diabetic healthy siblings and 12 non-diabetic healthy parents. Limiting dilution analysis (LDA) was performed to insulin and tetanus toxoid (TT). A progressive decrease in the number of negative cultures at increasing cell concentrations that is represented by a low goodness-of-fit (GoF, low Chi-square), was seen with the TT response in all three groups; precursor frequencies and GoF were similar in patients, siblings, and parents. Reactivity to insulin, however, showed low precursor frequencies in patients and siblings and the LDA to insulin demonstrated dramatic decreases in the number of positive cultures at higher cell concentrations leading to a high GoF in patients and siblings compared to parents. This saw-toothed pattern of reactivity to insulin is indicative of multiple hit kinetics and implies that the response is regulated. Consequently the precursor frequency of insulin autoreactive cells in patients and their siblings is probably much higher than calculated.  相似文献   
22.
The location of sensory, somatic, and autonomic neurons projecting to the pig cremaster muscle (CM) was studied by means of the retrograde neuronal tracer Fast Blue (FB) technique. FB was randomly injected in the left CM of four impuberal pigs and serial sections of sensory and autonomic ganglia and spinal cord were examined under a fluorescence microscope. Additionally, some indications about the number and size of labeled neurons were given. Sensory pseudounipolar somata were located ipsilaterally in the L2-L6 and S1-S2 dorsal root ganglia, their total number ranging between 125 and 194, their mean diameter between 24 and 89 microm. Somatic multipolar motoneurons were located ipsilaterally in the L2-L4 neuromeres of the spinal cord, their total number ranging between 53 and 169, their mean diameter between 29 and 53 microm. Autonomic multipolar paravertebral ganglia neurons were located ipsilaterally from L1 to S4 and contralaterally from L2 to S2. Their total number ranged from 2,015 to 3,067 and their mean diameter between 25 and 55 microm. The multipolar caudal mesenteric ganglia neurons were located bilaterally, their total number ranging between 14 and 1,408 and their diameter from 22 to 39 microm. In two subjects only, multipolar neurons were also found ipsilaterally in the microganglia of pelvic plexus (2 and 13 neurons). Their mean diameter ranged between 28 and 54 microm. Our study documented that the CM-projecting neurons were located at different neural levels, with a predominance in the autonomic ganglia.  相似文献   
23.
Subunit intranasal vaccines offer the prospect of inducing combined systemic-mucosal immunity against mucosally transmitted infections such as human immunodeficiency virus. However, although human studies have demonstrated the induction of active immunity, secretory immunoglobulin A (sIgA) responses are variable, and no study has demonstrated protection by accepted vaccine-licensing criteria as measured by direct toxin-neutralizing activity. Using the genetically inactivated mutant diphtheria toxoid CRM(197) in a bioadhesive polycationic polysaccharide chitosan delivery system, we found that a single nasal immunization was well tolerated and boosted antitoxin neutralizing activity in healthy volunteers, which could be further boosted by a second immunization. The neutralizing activity far exceeded accepted protective levels and was equivalent to that induced by standard intramuscular vaccine and significantly greater than intranasal immunization with CRM(197) in the absence of chitosan. A striking but unexpected observation was that although unilateral intranasal immunization induced circulating antitoxin antibody-secreting cells, a nasal antitoxin sIgA response was seen only after the second immunization and only in the vaccinated nostril. If these data are reproduced in larger studies, an intranasal diphtheria vaccine based on CRM(197)-chitosan could be rapidly licensed for human use. However, a restricted sIgA response suggests that care must be taken in the priming-boosting strategy and clinical sampling techniques when evaluating such vaccines for the induction of local mucosal immunity.  相似文献   
24.
25.
In this report, we describe our traction suture technique of the pericardium for suspension of the heart without hemodynamic instability to obtain excellent exposure in the abdominal-transhiatal approach (TH). Our technique is an application of deep pericardium stitches for off-pump coronary artery bypass surgery. In detail, the left hepatic lobe is detached at its triangular ligament from the diaphragm and is deflected to the right. Then, the tendinous portion of the diaphragm arching over the esophagus is incised upward in the midline until the pericardium is exposed. Pericardial fatty tissue was dissected. Three U-shaped sutures reinforced with a felt pledget are placed on the posterior aspect of the pericardium and diaphragm. A 15 Fr. flexible catheter is placed over both ends of the suture to avoid damage of the adjacent organs. Finally, the sutures are fixed to the drape of anterior wall of the patient to maintain good exposure.  相似文献   
26.
N19, a string of human universal CD4 T-cell epitopes from various pathogen-derived antigens, was shown to exert a stronger carrier effect than CRM197 for the induction of anti-group C Neisseria meningitidis capsular polysaccharide (MenC), after immunization of mice with various dosages of N19-MenC or CRM-MenC conjugate vaccines. After two immunizations, the N19-based construct induced anti-MenC antibody and protective bactericidal antibody titers higher than those induced by three doses of the CRM-MenC conjugate and required lower amounts of conjugate. N19-based conjugates are superior to CRM-based conjugates to induce protective immune responses to MenC conjugates.  相似文献   
27.
It still needs to be verified whether multiple syncronous homolateral and bilateral breast cancers represent intramammary spread of a single tumor or two or more separate neoplastic events. To clarify this problem, we studied the biopathological profile of 46 homolateral and 20 bilateral cases. The cancers were always surgically removed and processed at the same time. The expression of estrogen receptors (ER), progesterone receptors (PR), MIB 1, p53, and c-erbB-2 was determined. Computer-assisted image analysis (CAS 200) was used to evaluate ER, PR, MIB 1, and p53. The histological concordance was 95.6% in homolateral and 50% in bilateral cases. The immunophenotype profile of multiple homolateral neoplasms showed a concordance between 93.47% for ER and 78.26% for p53. The results were statistically significant for all parameters except for p53. In bilateral cancers, there was a significant statistical concordance for ER. These data strongly suggest that both mechanisms may exert an influence and, in particular, that in the majority of homolateral carcinomas, there may be intramammary spread of tumor cells. In multiple bilateral tumors, however, the great diversity of the histological aspects and the differences in the immunophenotype pattern suggest that the vast majority of these may constitute independent multiple events.  相似文献   
28.
Vaccination has played a significant role in controlling and eliminating life-threatening infectious diseases throughout the world, and yet currently licensed vaccines represent only the tip of the iceberg in terms of controlling human pathogens. However, as we discuss in this Review, the arrival of the genome era has revolutionized vaccine development and catalyzed a shift from conventional culture-based approaches to genome-based vaccinology. The availability of complete bacterial genomes has led to the development and application of high-throughput analyses that enable rapid targeted identification of novel vaccine antigens. Furthermore, structural vaccinology is emerging as a powerful tool for the rational design or modification of vaccine antigens to improve their immunogenicity and safety.  相似文献   
29.
Prostate carcinoma is the most common cancer in men. Its primary pathogenesis is mostly unknown. Dairy products containing lactose have been suggested to be risk factors for prostate cancer. Digestion of lactose is dependent on lactase activity in the intestinal wall. A single nucleotide polymorphism C to T residing 13,910 bp upstream of the lactase gene has been shown to associate with the developmental down-regulation of lactase activity underlying persistence/nonpersistence trait. To find out whether lactase persistence is related to the risk for prostate cancer, we genotyped 1,229 Finnish and 2,924 Swedish patients and their 473 Finnish and 1,842 Swedish controls using solid-phase minisequencing. To explore if dairy products have an association with prostate cancer, we analyzed the milk consumption in the Swedish study consisting of 1,499 prostate cancer patients and 1,130 controls (Cancer Prostate in Sweden I study) using a questionnaire. Only the consumption of low-fat milk was found to be associated with increased risk of prostate cancer [odds ratio (OR), 1.73; 95% confidence interval (95% CI), 1.16-2.39]. A statistically significantly higher (P < 0.01) lactose intake was observed among subjects with high lactase activity (C/T and T/T genotypes) compared with those with low lactase activity (C/C genotype). Lactase persistence did not associate with increased risk for prostate carcinoma in the Finnish (OR, 1.11; 95% CI, 0.83-1.47; P = 0.488) or in the Swedish populations (OR, 1.16; 95% CI, 0.91-1.46; P = 0.23). In conclusion, lactase persistence/nonpersistence contains no risk for prostate cancer. Analysis of different milk products showed some evidence for low-fat milk as a potential risk factor for prostate cancer.  相似文献   
30.
Information on correlates of total physical activity (PA) levels among middle-aged and elderly women is limited. This article aims to investigate whether total daily PA levels are associated with age, body mass index, smoking, drinking status, and sociodemographic factors.  相似文献   
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