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1.
A crude outer membrane preparation from Francisella tularensis Live Vaccine Strain (LVS) was used to immunize mice. Immunized mice were completely protected from a F. tularensis challenge. We evaluated the role of two major outer membrane antigens in the induction of protective immunity, namely lipopolysaccharide and an outer membrane protein FopA. We presented FopA to the immune system using an aromatic amino acid-dependent Salmonella typhimurium as a vector. Although mice mounted an immune response to cloned FopA no significant protection was induced. However, LPS immunized mice were completely protected. We conclude that LPS is a major protective antigen whereas FopA has a limited or no role in the induction of protective immunity.  相似文献   

2.
We are reporting the case of a 94-year-old male patient with a 10-year history of Parkinson's disease, who was admitted to our hospital with acute obstruction of esophageal passage. Esophageal obstruction was refractory to endoscopic intervention. However, discontinuation of the pre-existing levodopa medication led to its resolution within hours. While dysphagia is commonly encountered in patients with Parkinson's disease, the observed succession of drug discontinuation and resolution of obstruction in this case suggests an as yet rarely described side effect of levodopa. This potential side effect should be included in the differential diagnosis of dysphagia in Parkinson's disease, especially in the case of older patients, who may exhibit an increased rate of intestinal absorption of levodopa.  相似文献   

3.
The role of the citric acid cycle enzyme NADP-dependent isocitrate dehydrogenase (IDH-NADP) and its allele product variants in resisting the oxidative agent paraquat, was analyzed among descendants of reciprocal crosses between fast developmental time short-lived individuals (F-) and slow developmental time long-lived ones (S+), in Drosophila melanogaster. Taking preadult developmental time into account, the data suggested that IDH-NADP differences in enzymatic activity between electrophoretically fast and slow allele product variants could play an important role in paraquat resistance and longevity, because individuals with slow developmental time bearing the fast electrophoretic variant of IDH-NADP ("fast" allele) were the most resistant. The fast electrophoretic variant of this enzyme is known to be the most active one and its activity is related to increased reduction of NADP to NADPH. This process could be very important for an effective balance between several pathways that use NADPH as precursor molecules and the oxidative stress defense system that uses it as an oxygen free radical reductor. We also reported a strong maternal effect on these traits, because survivors of a paraquat bioassay carrying cytoplasm inherited from slow developmental long-lived females (S+ cytoplasm) showed the highest frequency of the fast electrophoretical variant of IDH-NADP.  相似文献   

4.
Yeast-phase lysate antigens were prepared from 10 different isolates of Blastomyces dermatitidis. Comparative studies were performed using the lysate antigens in an enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies in sera from dogs with blastomycosis and histoplasmosis. In order to evaluate the ability of the lysate reagents to elicit delayed dermal hypersensitivity (DTH) responses, the lysates were compared as skin-testing antigens in hairless guinea pigs that were previously sensitized with B. dermatitidis or Histoplasma capsulatum killed whole yeast cells. All ten of the lysate reagents were able to detect antibody with the ELISA in the serum specimens from dogs with blastomycosis (absorbance values ranged from 0.184 to 0.272; mean value 0.235). In contrast, when the lysates were assayed against sera from dogs with histoplasmosis, the absorbance values ranged from 0.053 to 0.151, with a mean value of 0.092. All ten lysate antigens were able to elicit a DTH response in the B. dermatitidis-immunized animals (mean axes of induration values ranged from 7.0 to 14.4 mm; mean value 8.6 mm). On the other hand, only minimal reactivity was evidenced in the guinea pigs immunized with H. capsulatum (mean axes of induration values ranged from 0.8 to 2.9 mm; mean value 1.8 mm).  相似文献   

5.
BACKGROUND: A rat-to-primate cardiac xenograft model has been proposed as an alternative to the clinically relevant but more cumbersome pig-to-primate model for assessing the efficacy of strategies aimed at preventing xenograft hyperacute rejection. As in pig xenografts, the rejection of rat hearts was mediated by the binding of xenoreactive natural antibodies (XNA) and complement activation. The present study was conducted to identify target antigens recognized by cynomolgus and rhesus monkey IgM XNA on rat tissues and cells in comparison with pig cells. METHODS: The reactivity of rhesus or cynomolgus serum on pig and rat endothelial cells (ECs) was studied by flow cytometry, ELISA, and complement-dependent cytotoxicity, after removal of primate XNA by perfusion of pig livers, immunoadsorption on a Gal alpha(1,3)Gal affinity column, and enzymatic removal of alpha-galactosyl epitopes from the cell surface. Rat and pig EC extracts were also immunoprecipitated with primate serum and resolved in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The expression of the Gal alpha(1,3)Gal epitope was analyzed on rat tissues and ECs by immunohistochemistry, flow cytometry, and Western blot, using the isolectin B4 from Griffonia simplicifolia. RESULTS: Removal of primate XNA or of alphaGal epitopes resulted in a decrease in XNA binding to pig and rat cells, leaving a similar degree of residual reactivity in the two species. At least five proteins of 260, 210, 110, 56, and 50 kDa were immunoprecipitated on rat ECs, with molecular weight similar to several proteins identified on pig ECs. These results suggest that primate XNA recognize similar antigens on rat and pig ECs. Rat cells expressed lower levels of the Gal alpha(1,3)Gal epitope than pig cells. A large proportion, but not all, of primate XNA react with this epitope on pig and rat ECs. CONCLUSION: This study suggests that the rat is a valuable species for the evaluation of genetic engineering strategies on the vascular endothelium aimed at preventing hyperacute xenograft rejection.  相似文献   

6.
Studied the predictive validity of Stange Situation classifications among infants raised on kibbutzim in Israel. C-type (resistant) attachments are frequently found on Israeli kibbutzim, but the long-term correlates of this "insecure" pattern have not been identified. 59 Ss, whose attachments to parents and metaplot were assessed at age 11–14 mo, were seen again when they were 5 yrs old to assess socioemotional development. Ss who had B-type attachments to their metaplot were later less ego controlled and more empathic, dominant, purposive, achievement-oriented, and independent than C-group Ss. Group differences were in the direction predicted on the basis of prior research on the correlates of infant–mother attachment. Measures of socioemotional development reflected Ss' behavior at the kibbutz but not at home or with parents. This may explain the relatively strong predictive power of attachment status with metapelet as opposed to attachment status with parents. Results may underscore the central importance of the careprovider as a key figure in the early social life of kibbutzim. Findings raise questions regarding developmental significance of attachment relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
The Nazi attempt to annihilate the Jewish people ended over 50 yrs ago, but both public and scholarly interest in the Holocaust remains intense and has a salient psychological component. The Holocaust continues to be the setting for many novels, plays, and films, and is also frequently invoked as a metaphor in policy debates such as in justification of the NATO air attacks against Yugoslavia. Holocaust-related psychological research can serve as a basis for better understanding of subsequent, and perhaps of future, ethnopolitical violence, the focus of the ongoing joint Canadian Psychological Association–American.Psychological Association Ethnopolitical Warfare Initiative. This research includes theories of why people participate in genocide, the analysis of bystander and rescuer behavior, and the development of interventions that may help to prevent or de-escalate ethnic conflicts and to ameliorate their effects. Psychological studies of Holocaust survivors have contributed to our knowledge of posttraumatic stress disorder (PTSD), the transmission of trauma to subsequent generations, and the possibility of coping and recovery after extreme stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Blood leukocyte patterns, neutrophil phagocytosis of killed Escherichia coli in vitro, and plasma corticosteroids were studied in colostrum-fed (CF) and colostrum-deprived (CD) calves during the 1st 144 hours after birth. There was a marked increase in neutrophil numbers between 6 and 12 hours in CF but not CD calves, apparently as a result of colostrum ingestion. Phagocytosis was inactive at birth but increased quickly thereafter. Phagocytosis was more efficient in CF than in CD calves. Plasma corticosteroid concentrations were high at birth and decreased quickly thereafter in both groups of calves.  相似文献   

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The appearance and course of serum immunoglobulin E-antibodies (IgE-ab) to egg-white (EW), cow's milk (CM) and inhalants (pollen, danders and mite) were followed from birth to 12 years of age in 84 children unselected for family history of atopy. During the follow-up 36 children developed atopic symptoms and 48 children did not. IgE-ab to EW and CM reached a peak prevalence at 8 months of age--with high concentrations almost exclusively in atopics and disappeared successively during childhood. IgE-ab to inhalants appeared from 2 years of age and then in increasing frequency during childhood. Similar to the pattern of IgE-ab to EW and CM, transient low levels of IgE-ab to inhalants were commonly encountered in non-atopic children while high concentrations without tendency to decline were almost exclusively seen in atopics. High responders to EW-antigen during infancy were usually also high responders to inhalants during childhood. Clinical allergy to EW and CM and subsequent tolerance appeared early in childhood, whereas allergy to inhalants appeared later and did not disappear. The temporary low-grade IgE antibody response in non-atopic individuals to eaten and inhaled allergens is similar to the results of animal studies demonstrating a transient IgE production followed by tolerance.  相似文献   

12.
Comparative data on production of complement-binding and hemagglutinating antibodies in the process of the antigenic effect of benzylpenicillin under experimental conditions are presented. 30 rabbit antisera and 3 sera of intact animals were studied. The hemagglutinating antibodies were determined in 19 antisera, high and reliable titers of the antipenicillin hemagglutinating antibodies being found only in 8 antisera. The antipenicillin complement-binding antibodies using complex antibiotic antibodies were also found in 19 antisera. The process of antibody production was more pronounced in the complement-binding reaction (CBR). Both types of the antibodies were detected simultaneously in 14 antisera. It is concluded that the CBR with the use of the penicillin complex antigenes on the stroma of the erythrocytes and in combination with the blood serum is a rather sensitive reaction for detection of antipenicillin antibodies.  相似文献   

13.
Idiotypes (Id) that stimulate immunoregulatory anti-Id T lymphocyte proliferation are expressed on murine and human antibodies (Ab) to soluble egg antigens (SEA) of Schistosoma mansoni. Kinetics of early expression of these stimulatory Id have now been studied using immunoaffinity-purified serum anti-SEA Ab from mice infected with S. mansoni for 6, 7, 8, 12, or 16 weeks. Rabbit anti-Id Ab specific for mouse anti-SEA Id expressed at 8 weeks post-infection (anti-8WkId) demonstrated the strongest interactions with Id present at 7 and 8 weeks post-infection by competitive enzyme-linked immunosorbent assay. Anti-8WkId Ab reacted progressively less well with 12 WkId, 6WkId, and 16WkId. Splenocytes from mice infected for 8 weeks demonstrated the highest blast transformation responses in vitro to anti-SEA Id from mice infected for 6 weeks, while 7, 8, 12, and 16 weeks post-infection Id preparations stimulated progressively less proliferation. These data indicate that although eventual Id-associated immunoregulatory events contribute to chronicity in this disease, production of anti-SEA Ab that express stimulatory cross-reactive immunoregulatory Id comprises a substantial portion of the initial, acute anti-SEA response in mice infected with Schistosoma mansoni. Furthermore, either this particular Id-expressing response is not maintained, or its proportional presence is greatly diminished by the cumulative production of other multiple anti-SEA Ab during the establishment of chronicity, perhaps in response to its immunoregulatory influence very early in infection.  相似文献   

14.
Light chain deposition disease is a severe complication of certain immunoproliferative disorders, due to the secretion of a monoclonal light chain which precipitates close to basement membranes of several tissues. A kappa isotype restriction and an unusual frequency of a variable region subgroup (VkappaIV) suggest that precise structural features govern the propensity of pathogenic light chains to precipitate in extracellular spaces. We studied primary structures of light chains from six patients with light chain deposition disease in comparison with light chains from other pathological conditions. Sequence alignment revealed the presence of certain amino acids only in light chain deposition disease, in particular non-polar replacing hydrophilic residues. To determine the role of these residues, structures of the variable domain from four kappa chains belonging to VkappaI and VkappaIV subgroups responsible for deposition disease were modeled using known immunoglobulins as templates. The most evident structural features shared by all pathogenic light chains were hydrophobic residues exposed to the solvent in complementarity determining regions 1 or 3. In contrast to immunoglobulin light chain-related amyloidosis, where deposition of organized material might be due to electrostatic interactions between light chain dimers, hydrophobic interactions could enhance amorphous precipitation in non-amyloid light chain deposition disease.  相似文献   

15.
This study examined patterns, variations, and existential turning points in young mothers' narratives of self and their visions of the future as part of a larger hermeneutic, longitudinal study. The study was philosophically based in the phenomenology of everyday practices as inherently meaningful, situated, and historically derived and drew on dialogical views of the self. The sample consisted of 13 (of the original 16) young mothers and family members who had been interviewed 4 years earlier. For the present study, data consisted of life history accounts of the intervening 4 years, stories of caregiving routines, and recent coping episodes of parenting elicited through in-depth interviews. Findings offer a situated understanding of young mothering and highlight meaningful distinctions in the ways young mothers experience the self and project themselves into the future. The discovery of patterns and variations in the young mother's sense of self and future have implications for guiding clinical practice and are preliminary to designing programs and interventions that are tailored to the practical understanding and situated possibilities of young mothers.  相似文献   

16.
Nocardia opaca, a Gram-positive bacterium, is a potent source of immunostimulatory substances. Screening of sera of adult human donors revealed that all sera tested contained antibodies reactive with isolated Nocardia fractions (Nocardia delipidated cell mitogen, NDCM; Nocardia lysozyme digest, NLD; Nocardia water-soluble mitogen, NWSM; and fraction B). The respective values of reciprocal titres for IgM and IgG were in the range of 100 to 12,800, and 10 to 320 for IgA antibody isotypes, when NLD or fraction B were used as antigens in enzyme-linked immunosorbent assay (ELISA) tests. The level of antibodies directed to NDCM, a potent polyclonal B cell activator, was found to be the lowest. In vitro spontaneous as well as NDCM-induced production of antibodies to NDCM by human peripheral blood lymphocytes involved mainly the IgM class. Western-blot analysis demonstrated that antibodies in normal human sera react with nocardial antigens of molecular mass approximately 60, 40, 20 and 15-10 kDa. The same antigens were also recognized by rabbit and mouse hyperimmune sera, also confirming the immundominancy of these nocardial antigens in other species. The presence of anti-nocardia antibodies in human sera and their production by both stimulated and non-stimulated lymphocytes points to the natural sensitization of humans either by ubiquitous no-cardial components or by cross-reactive bacterial or food antigens.  相似文献   

17.
BACKGROUND: The Gleich syndrome is rare and associates recurrent angioedema, urticaria, fever, weight gain and blood hypereosinophilia, underlying systemic and local inflammation. The pathogenesis of those symptoms remains unclear. OBJECTIVE: We wanted to address the possible implication of Interleukin-6 (IL-6) in the development of those clinical features, and to identify the cells involved in its production. METHODS: A 26-year-old man suffering of this disease was referred in hospital. During an acute attack with weight gain, fever and a diffuse oedema, a marked increase in eosinophils count (42700/mm3 was observed. Serum ECP was elevated at 47 microg/L (normal less than 16). Corticosteroid therapy administrated on the 7th day was followed by a rapid remission. Blood samples were collected (before, during the attack and under corticosteroid therapy) for measurements of serum IL-6 (ELISA, Immunotech, Marseille, France) and plasma histamine (RIA, Immunotech, Marseille, France). Blood monocytes and eosinophils were isolated and a skin biopsy was performed during the attack. RESULTS: The plasma histamine level was within normal range. The level of IL-6 in sera peaked to 74 pg/mL, concomitant with the peak of eosinophilia at the acute phase phase of the attack. Under corticosteroids, we observed a drop in the IL-6 serum level to 29 pg/mL, concomitant with the clinical remission. During the attack, an increase in IL-6 production was observed in 24 h blood monocyte supernatants (11.10(3) pg/mL compared with 2.4+/-0.8.10(3) pg/mL for BM from controls) as well as in skin endothelial cells but not in the blood and skin eosinophils. In vitro, when endothelial cells were incubated in eosinophils supernatants of the patient, liberation of IL-6 was observed (3.3 10(3) pg/mL compared with controls: 2.1 10(3) pg/mL) CONCLUSION: Serum IL-6 elevation may be related to an increased production by blood monocytes and endothelial cells, possibly stimulated by eosinophil mediator during the acute phase of the disease, and might participate in the inflammatory reaction of this syndrome.  相似文献   

18.
We evaluated personality change following head injury in 68 patients at 6 months postinjury using the NEO Five-Factor Inventory to assess the five personality dimensions of the Five-Factor Model of Personality. All items had to be rated twice, once for the preinjury and once for the current status. Twenty-eight trauma patients with injuries to other parts of the body than the head were used as controls. For the head-injured group, 63 relatives also completed the questionnaire. The results showed no differences between the ratings of head-injured patients and the ratings of trauma control patients. Both groups showed significant change in the personality dimensions Neuroticism, Extraversion, and Conscientiousness. Compared to their relatives, head-injured patients report a smaller change in Extraversion and Conscientiousness. Changes were not reported on the Openness and Agreeableness scales, by neither the head-injured or their relatives, nor by the trauma controls.  相似文献   

19.
We present a new method to detect epididymal sperm aneuploidy (ESA) in mice using simultaneous fluorescence in situ hybridization (FISH) with DNA probes specific for mouse chromosomes X, Y and 8. The method was applied to Robertsonian (Rb) translocation (8.14) heterozygotes and homozygotes as well as the chromosomally normal B6C3F1. The sex ratios of sperm did not differ from the expected 1:1 and the hybridization efficiencies were approximately 99.7% for over 60 000 sperm analyzed. Mice heterozygous for Rb (8.14) produced about tenfold higher rates of sperm with chromosome 8 hyperhaploidy than did Rb (8.14) homozygotes or chromosomally normal mice, while frequencies of sperm with hyperhaploidies for chromosomes X and Y were unaffected in all three lines of mice. Hyperhaploid frequencies obtained with the ESA method were consistent with those of the previous testicular FISH method and were validated by published data obtained by conventional cytogenetic analyses (meiotic metaphase II and first cleavage). Thus, the mouse three-chromosome ESA assay together with the previously developed aneuploidy assay for human sperm constitute a promising pair of interspecific biomarkers for comparative studies of the genetic and physiologic mechanisms of the induction and persistence of aneuploidy in male germ cells.  相似文献   

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