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31.
OKT3-, OKT4- and OKT8-positive cells were estimated in 303 children with recurrent respiratory infections. The patients (selected by a score method) had experienced 13 or more infections a year. Modifications in T-cell subsets were observed in 154 patients (50.8%). Decreased OKT3- and OKT4-positive cells were present in 80 children (26.4%), while 74 patients (24.4%) showed normal values of OKT3-positive cells but decreased OKT4- and increased OKT8-positive cells. An attempt at treatment with thymostimulin was undertaken in a group of randomly chosen children with modifications in T-cell subsets. The use of thymostimulin induced the treated children more readily than the untreated ones to show improvement in both the score for respiratory infections and the distribution of T-cell subsets.  相似文献   
32.
Releasability of human basophils (i.e., the response to a standard stimulus) is an important parameter in several pathophysiologic conditions. We studied the IgE (anti-IgE)- and non-IgE-mediated (f-met peptide and Ca2+ ionophore A23187) releasability of human basophils obtained from 63 normal donors whose ages ranged from 1 to 86 years. The maximum percent of histamine release induced by anti-IgE was significantly correlated (rs = 0.57; p less than 0.001) with the age of donors. The sensitivity to a standard concentration of anti-IgE (3 X 10(-2) mcg/ml) was also correlated with the age of cell donors (rs = 0.68; p less than 0.001). In the population of 63 donors tested, the maximum percent of histamine release and the cell sensitivity to anti-IgE appeared to be independent of the serum concentration of IgE. However, we found a positive correlation (rs = 0.55; p less than 0.05) between serum IgE level and anti-IgE-induced histamine release in the group less than 20 years of age. In contrast, a negative correlation (rs = -0.32; p less than 0.05) between serum IgE level and anti-IgE-induced histamine secretion was found in the group greater than 21 years of age. The maximum percent of histamine release induced by f-met peptide and Ca2+ ionophore A23187 appeared to be independent to both the age of the donors and the serum IgE level.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
33.
E-selectin, an adhesion molecule of the selectin family, is involved in leukocyte adhesion to the endothelium and in the cellular immunological reactions. Expression of this molecule, in fact, is physiologically absent, but it becomes evident on sinusoidal lining cells during inflammatory liver disease. The aim of this study was to evaluate the behavior of E-selectin in chronic hepatitis C (CH-C) patients with persistently normal transaminase in comparison to patients with CH-C and elevated transaminase, and its changes during alpha-interferon therapy. Immunohistochemical localization of E-selectin was also performed on liver tissue specimens of both groups. Fifty-eight subjects were divided into 3 groups: group A included 18 patients with CH-C and persistently normal transaminase; group B 20 patients with CH-C and persistently elevated transaminase levels and group C included 20 healthy subjects, representing the control group. The first two groups were treated with r-IFN at a dose of 6 MU 3 times a week for 3 months and followed-up with 3 MU 3 times a week for another 3 months. Serum baseline values of E-selectin in groups A and B were significantly higher than those in group C (P < 0.04), but there was no difference between groups A and B. Furthermore, there was a trend toward higher E-selectin values as histological severity increased (r = 0.69; P < 0.0001). Post-treatment E-selectin serum values showed a moderate decrease in both groups, but only among responder patients; while E-selectin levels were unchanged in non responders. Immunohistochemical localization showed no staining for E-selectin in normal liver specimens, while there was a quite similar staining for E-selectin in the two groups of patients. In conclusion, this study shows that serum E-selectin levels in patients with CH-C and persistently normal transaminase are higher than in controls and they are associated with severity of liver disease. Liver of these patients express E-selectin molecules, suggesting an activation of the immune system almost identical to that of patients with CH-C and elevated transaminase. In both groups only responder patients showed a moderate decrease below baseline serum values.  相似文献   
34.
In a series of 342 bone marrow examinations from 314 patients with human immunodeficiency virus infection, 70 examinations (20%) detected opportunistic mycobacterial or fungal infections. One hundred eleven of the 314 patients had such infections, and, hence, 63% (70/111) were detected by bone marrow examination. Special stains for microorganisms detected 16 (32%) of 50 Mycobacterium avium complex infections, 10 (22%) of 45 Mycobacterium tuberculosis infections, eight (73%) of 11 Histoplasma capsulatum infections, and five (83%) of six Cryptococcus neoformans infections. Bone marrow cultures detected 36 (72%) of the 50 M avium complex infections, 13 (29%) of the 45 M tuberculosis infections, and 63% of the fungal infections. Marrow examination revealed infection in only one of the 70 specimens (1%) collected to evaluate thrombocytopenia alone or hematologic malignancy, but in 69 (25%) of 274 with fever, neutropenia, anemia, or miscellaneous other indications for marrow examination. Granulomas were detected in 102 (30%) of the biopsy specimens, including 71 (64%) of those in cases with mycobacterial or fungal infection. The granulomas showed caseous necrosis in nine cases, all in patients with tuberculosis, and the 27 cases with tuberculosis-associated granulomas tended to show large, tightly cohesive granulomas. The presence of granulomas correlated with opportunistic infection in 82 (80%) of 102 cases. Without granulomas, special stains were positive in only eight (3%) of 240 specimens. These results suggest that (1) bone marrow granulomas are a common and valuable histologic clue to opportunistic infection; (2) without them, special stains may not be a cost-efficient way to diagnose such infection; and (3) bone marrow examination can be a useful method of diagnosing opportunistic mycobacterial and fungal infections in patients with fever, anemia or neutropenia, and underlying human immunodeficiency virus infection.  相似文献   
35.
Neonatal hypothyroidism induces striatal dopaminergic dysfunction   总被引:2,自引:0,他引:2  
Oral administration of the antithyroid drug methimazole (50 mg/kg per day) to rats during the last six days of pregnancy, and subsequent daily s.c. injection of methimazole (20-30 mg/kg) to their pups from birth to postnatal day 30 provoked hormonal and somatic alterations resembling (with all caution to any association between rodent and human data) those of congenital hypothyroidism. The steady-state concentrations of striatal dopamine were similar in hypothyroid and euthyroid, 32-day-old rats, while the levels of the dopamine metabolites 3,4-dihydroxyphenylacetic and homovanillic acids were markedly decreased in hypothyroidism. The results of this and our earlier study [Vaccari A. and Gessa G. L. (1989) Neurochem. Res. 14, 949-955] show that the maximal synaptosomal uptake of [3H]dopamine, an index for the density of nigrostriatal dopaminergic terminals, and the maximum number of membrane [3H]tyramine binding sites, reflecting the concentration of the vesicular transporter for dopamine, were decreased in the hypothyroid striatum. There was also a loss of those D1-type dopaminergic receptors claimed to be located on neurons intrinsic to the striatum, and, consequently, dopamine-stimulated, D1-regulated adenylate cyclase activity was depressed. It is suggested that individual dopaminergic nerve endings in the neonatal hypothyroid striatum must contain more dopamine, owing to some loss of pertinent innervation and, therefore, to the presence of less vesicular transport sites for dopamine. Hypothyroidism-related decreases in the maximum number of striatal D1- and, reportedly, D2-receptors, plus the impairment of D1-coupled second messenger activity, may play a role in the derangement of those neurobehavioural patterns where a dopaminergic regulation is putatively implied.  相似文献   
36.
A questionnaire-based retrospective clinical and immunological survey was conducted in 73 males with a definite diagnosis of X-linked agammaglobulinemia based on BTK sequence analysis. Forty-four were sporadic and 29 familial cases. At December 2000, the patients' ages ranged from 2 to 33 years; mean age at diagnosis and mean duration of follow-up were 3.5 and 10 years respectively. After the mid-1980s all but 2 were on intravenous immunoglobulin (IVIG) substitution therapy, with residual IgG >500 mg/dl in 94% of the patients at the time of enrollment. Respiratory infections were the most frequent manifestation both prior to diagnosis and over follow-up. Chronic lung disease (CLD) was present in 24 patients, in 15 already at diagnosis and in 9 more by 2000. The cumulative risk to present at diagnosis with CLD increased from 0.17 to 0.40 and 0.78 when the diagnosis was made at the ages of 5, 10, and 15 years respectively. For the 9 patients who developed CLD during follow-up, the duration of follow-up, rather than age at diagnosis; previous administration of intramuscular immunoglobulin; and residual IgG levels had a significant effect on the development of CLD. Chronic sinusitis was present in 35 patients (48%), in 15 already at diagnosis and in 20 by 2000. Sistemic infections such as sepsis and meningitis/meningoencephalitis decreased over follow-up, probably due to optimal protection provided by high circulating IgG levels reached with IVIG.  相似文献   
37.
Thirty-six cases of enterococcal septicemia in patients with hematological malignancies were reviewed retrospectively and categorized according to their clinical significance using strict previously described definitions. Overall, most of the infected patients were males (77 %), had acute leukemia (64 %), had recently received cytotoxic drug therapy (86 %), were granulocytopenic at the onset of septicemia (77 %), and acquired the infection during hospitalization (77 %). The source of septicemia was unknown in 18 (50 %) patients, intestinal in 15 (42 %) and intravascular in three (8 %). Mortality was 19 % among 21 inpatients who had clinically significant septicemia and 30 % among patients with septicemia of uncertain clinical significance. The fatal outcome could be definitively attributed to enterococcal septicemia in only one of the nine inpatients who died. Clinically significant septicemia appeared somewhat more frequently to be polymicrobial (p=0.06), whereas septicemia of unknown significance presented more frequently as breakthrough septicemia (p=0.013). Unless associated with intravascular infection, enterococcal septicemia in patients with hematological malignancies seems to represent a marker of cytotoxic drug damage of the intestinal mucosa rather than a truly invasive infection.  相似文献   
38.
Antibodies were raised against a synthetic dodecameric peptide KGAGQVVAGPWK (K12K), encompassing sequences thought to be important for the function of the cysteine proteinase inhibitors of the cystatin superfamily. These antibodies specifically recognized molecules of family 3, i.e., kininogens, in the serum of seven mammalian species tested in this study. The only notable exception was that of rat thiostatin (T kininogen) which is structurally related to the kininogen family. The antibodies also discriminated between family 2 (cystatins) and family 3 (kininogens) of the cystatin superfamily, since neither chicken cystatin nor human and rat cystatins C and S, which all belong to family 2 were recognized. The cystatin-like inhibitory domains resulting from fragmentation of human low molecular weight kininogen by bovine trypsin, were still recognized by antibodies, indicating that discrimination does not require two neighbouring inhibitory sites on the kininogen heavy chain. The antibodies blocked the capacity of kininogens to inhibit papain, suggesting that they recognize a conformational epitope at or near the kininogen inhibitory sites. The inhibitory properties of family 2 cystatins remained unchanged, confirming that members of this family do not interact with anti K12K antibodies. These antibodies are thus a new tool able to discriminate functionally and structurally between the members of the cystatin superfamily.  相似文献   
39.
M. De  Martino  E. Novembre    G. Cozza    A. De  Marco  P. Bonazza  A. Vierucci 《Allergy》1988,43(3):206-213
Possible associations between allergy to grass pollen and positive skin tests to food allergens were studied in 102 children monosensitized (as to inhalant allergens) to grass pollen, and in 117 children monosensitized (as to inhalant allergens) to Dermatophagoides. Thirty-two foods were tested by an epicutaneous method. Positive skin tests to food allergens were more frequent in children with allergy to grass pollen (59.8%) than in children with allergy to Dermatophagoides (9.4%). A considerably high frequency of positive reactions to tomato (39.2%), peanut (22,5%), green pea (13.7%), and wheat (11.7%) was observed in children with allergy to grass pollen. Positive skin tests to peanut closely correlated with positive RAST results and nasal provocation tests, whereas in children with skin test positivity to tomato a close correlation with nasal provocation tests but a 45% correlation with a positive RAST result were observed. RAST inhibition experiments were carried out, and the results may suggest the presence of cross-reacting IgE to grass pollen, tomato, and peanut antigens. Clinical implications of these findings are discussed in the light of histories of food hypersensitivity, urticaria-angioedema, and atopic dermatitis in children with allergy to grass pollen.  相似文献   
40.
PURPOSE: The role of genetic susceptibility to esophageal adenocarcinoma and its precursor lesion Barrett esophagus has not been fully elucidated. This study investigated the effect of polymorphisms in the manganese superoxide dismutase (MnSOD) and NAD(P)H:quinone oxidoreductase 1 (NQO1) genes in modulating the risk of developing Barrett esophagus or esophageal adenocarcinoma. METHODS: A total of 584 patients (146 esophagitis, 200 Barrett esophagus, 144 esophageal adenocarcinoma, and 94 controls) were genotyped for the MnSOD C14T and NQO1 C609T polymorphisms using polymerase chain reaction and restriction fragment length polymorphism analysis. RESULTS: The NQO1 TT genotype was less common in Barrett esophagus (2.0%) and esophageal adenocarcinoma (1.4%) patients, compared with both esophagitis patients (7.6%) and controls (5.4%). After adjustment for sex, age, body mass index, reflux symptoms, and smoking status, patients with the homozygous TT genotype had a 4.5-fold decreased risk of developing Barrett esophagus (odds ratio = 0.22, 95% confidence interval = 0.07-0.76, P = 0.01) and a 6.2-fold decreased risk of esophageal adenocarcinoma (odds ratio = 0.16, 95% confidence intervals = 0.03-0.94, P = 0.04) compared with individuals with the TC and CC genotypes. No significant differences between groups were observed for the MnSOD polymorphism (P = 0.289). CONCLUSIONS: Overall, the results of this study suggest that the NQO1 TT genotype may offer protection from reflux complications such as Barrett esophagus and esophageal adenocarcinoma.  相似文献   
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