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31.
We describe here, to our knowledge for the first time, associations between polymorphisms at the genomic DNA level in the immunoglobulin gene region and renal diseases which lead to chronic renal failure. Recent studies have shown that protein polymorphisms, present in immunoglobulin (Ig) heavy chains (Gm allotypes) are associated with certain forms of renal disease and with end stage renal failure per se. To investigate this association at the DNA level we have used probes which recognize Ig heavy chain genes and this report describes results obtained with one of these, the S mu switch region probe. With the restriction endonuclease Sst 1 (or the isoschizomer; Sac I) a number of restriction fragment length polymorphisms (RFLP) can be obtained which are recognized by this probe and there is a highly significant association between certain of these and renal disease. This is the first report of Ig switch region polymorphisms being associated with disease, yet our results suggest that S mu RFLP are more closely linked to renal disease than Ig protein polymorphisms.  相似文献   
32.
Wildbaum G  Nahir MA  Karin N 《Immunity》2003,19(5):679-688
Therapies that neutralize the function of TNF-alpha suppress rheumatoid arthritis (RA) but not osteoarthritis (OA). We show that patients suffering from RA but not OA have significant levels of autoantibodies directed to TNF-alpha. Thus, the immune system can selectively generate autoimmunity to proinflammatory mediators when such a response is beneficial for the host. A well-defined model of RA was used to elaborate the contribution of beneficial autoimmunity to the regulation of disease. We show that during the disease autoantibody production is elicited against few inflammatory, but not regulatory, mediators. Selective amplification of these beneficial antibodies by targeted DNA vaccines provided protective immunity. Epitope mapping revealed that anti-TNF-alpha immunity is highly restricted and excretes no crossreactivity to other known gene products. Its selective exclusion substantially exacerbated the disease. Administration of anti-TNF-alpha antibodies could then override this aggravation. This substantiates the significance of beneficial autoimmunity in restraining self-destructive immunity.  相似文献   
33.
It has been extensively documented the role of the indirect pathway of allorecognition in allograft rejection. However, recent data demonstrate that the manipulation of this pathway could be also sufficient to promote prolongation of allograft survival. In the present study we evaluated the effect of preoperative immunization with the WF-specific MHC class II peptides RT1.D2 and RT1.B2 in combination with low-dose CsA from days 0 to 7 (5 mg/kg/day) and from days 8 to 30 (1 mg/kg/day) after WF small bowel transplantation. Seven days before and on the day of transplantation, LEW recipients were immunized with the two WF MHC class II peptides RT1.B2 and RT1.D2. The CsA monotherapy induced an allograft survival of 49.3 +/- 6.1 days. MHC class II peptide immunization had a limited effect on allograft survival for RT1.D2 (47.1 +/- 3.8 days) and induced prolongation of allograft survival for RT1.B2 (73.6 +/- 34.6 days). This effect seems to be based on the absence or silence of RT1.B2-reactive T cells and rejection seems to be correlated with the presence of RT1.B2-specific T cells in the late phase. Therefore, the combination of RT1.B2 with low-dose CsA shifts the immunological response and protects small bowel allograft rejection.  相似文献   
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35.
We sought to investigate associations between knowledge about the disease and sick leave, health complaints, functional limitations, adaptation and perceived control. Patients with asthma (n = 101) and COPD (n = 64) underwent lung function tests and completed questionnaires. In addition, all were asked the question: ‘what is the diagnosis of your disease?’, with the response categories: ‘asthma’ and ‘COPD (chronic bronchitis or emphysema)’. Thirty-five percent of the asthma patients and 30% of the COPD patients did not know their correct diagnosis. Sick leave was not associated with knowledge about the disease in asthma and COPD. In asthma, much knowledge about management of the disease was associated with better adaptation (P = 0.01) and less perceived control over health by external factors (P = 0.02). Knowing the correct diagnosis was associated with less control over health by powerful others (P = 0.02). For COPD, more knowledge about management of the disease was associated with better adaptation (P = 0.02) and less control over health by internal factors (P = 0.01). Knowing the correct diagnosis was associated with less control over dyspnea at work (P = 0.01).  相似文献   
36.
The human epidermis has the full machinery for autocrine L-phenylalanine turnover to L-tyrosine in keratinocytes and melanocytes. Phenylalanine hydroxylase (PAH) activities increase linearly with inherited skin colour (skin phototype I-VI, Fitzpatrick classification) yielding eightfold more activities in black skin compared to white skin. Moreover, UVB irradiation (1 MED) significantly increases epidermal PAH activities 24 h after exposure. Importantly, L-phenylalanine uptake and turnover in the pigment forming melanocytes is vital for initiation of melanogenesis. In this context it was shown that the uptake of this amino acid is regulated by calcium. The depigmentation disorder vitiligo provides a unique model to follow impaired L-phenylalanine turnover in the skin as well as in serum because affected individuals hold an impaired epidermal 6BH4 de novo synthesis/recycling and regulation including low epidermal PAH activities. After overnight fasting and oral loading with L-phenylalanine (100 mg/kg body weight), 29.6% of 970 patients tested (n=287/970) yielded serum phenylalanine/tyrosine ratios >or=4 and 35.3% (n=342/970) had mild to moderate hyperphenylalaninaemia (HPA), while 9.3% (n=90/970) had both serum L-phenylalanine levels >or=2.0 mg/dl and phe/tyr ratios >or=4.0. Isolated HPA was found in 26% (n=252/970), whereas 20.3% had only increased ratios (n=197/970). None of the patients had phenylketonuria and the family history for this metabolic disease was negative. The IQ followed normal Gaussian distribution. In vitro L-phenylalanine uptake/turnover studies on primary epidermal melanocytes originating from these patients demonstrated a significantly decreased calcium dependent L-phenylalanine uptake and turnover compared to healthy control cells. Based on our observation, we would like to propose that phenylalanine uptake/turnover is under tight control by calcium which in turn could offer an additional novel mechanism in the aetiology of HPA.  相似文献   
37.
This study aimed to investigate the inter-relation between the angiotensin II (ANG II) AT1 receptor and renin gene expression in rat kidneys. To this end, renin mRNA levels and mRNA levels for AT1a and AT1b were assayed by RNase protection in the kidneys of normal rats, in animals treated with the AT1 antagonist losartan and in rats bearing 0.2-mm left renal artery clips for 2 days. In normal rats, we found a negative correlation between renin mRNA levels and AT1a receptor mRNA levels. Losartan led to a fourfold increase in renin mRNA levels without changing AT1 receptor mRNA levels. Unilateral renal artery clipping increased renin mRNA levels fourfold in the clipped kidney and suppressed renin mRNA levels in the contralateral kidneys. AT1 receptor mRNA levels were not changed in the contralateral intact kidneys, but were significantly decreased by 15–25% in the clipped kidneys. Renin mRNA levels were inversely correlated to AT1a mRNA levels in the clipped, but not in the contralateral, kidneys. Our findings suggest that the systemic activity of the renin angiotensin system has no regulatory influence on renal AT1 receptor gene expression. Renin mRNA levels in normal and in clipped kidneys appear to be negatively determined by the level of AT1a receptor gene expression. Thus modulation of AT1a receptor gene expression could be a pathway for indirect modulation of renin gene expression by ANG II. This conclusion is in agreement with the observation that AT1 receptor antagonists are powerful stimulators of the renin system.  相似文献   
38.
39.
BACKGROUND: Retrospective cohort study to evaluate differences in outcome when embryo transfer was performed either on day 2-3 (cleavage stage, CS-group) or on day 4-5 (blastocyst stage, BS-group). METHODS: A total of 1259 consecutive cycles yielding 500 live born babies performed at a single centre in Bregenz, Austria, were included. Main outcome measures were implantation and (multiple) pregnancy rates and neonatal outcome including birth defects. RESULTS: Total Pregnancy rate was 44% vs 28% (P < 0.001) and the total 'take home baby rate' was 37% vs 22% in the BS-group and the CS-group, respectively. Rate of multiple gestations (34% vs 17%, P = 0.001) was significantly higher among the BS-group, resulting in a higher rate of preterm deliveries < 36 weeks (26% vs 17%, P = 0.045). Female factor causing infertility (40% vs 21%, P < 0.001) was significantly higher among the BS-group. For the CS-group, rate of singleton pregnancies (83% vs 66%, P = 0.001) and idiopathic cause of infertility (34% vs 22%, P = 0.012) were significantly higher. No statistically significant differences were found in sex, Caesarean section rate, Apgar score and umbilical artery pH-values, total mean birth weight, admission rate to intensive care unit, days of hospitalization and number of minor and major birth defects. CONCLUSIONS: Our data suggest that blastocyst transfer may lead to a higher pregnancy rate with an overall better take-home baby rate (THBR) at the cost of higher rates of multiples and preterm deliveries.  相似文献   
40.
The frequency distribution of Anisakis simplex L3 larvae between host tissues was investigated in three host species: saithe, cod and redfish. Fish were sampled from Norwegian coastal waters and examined for the presence of A. simplex in muscle and viscera. In all three of the host species, A. simplex larvae were most frequently detected in the viscera; the percentages of total infection for saithe, cod and redfish were 99.6%, 97.8% and 88.0%, respectively. In general, the distribution patterns of A. simplex L3 between muscle and viscera were not significantly affected by host size. The observations that distributions vary between species and are not affected by host size do not support an earlier hypothesis which states that A. simplex L3 distributions are determined by an optimal pre-encapsulation migratory distance within host tissues. In contrast, it is suggested that A. simplex L3 distributions are governed by the conditions encountered within host tissues, and are possibly related to the availability of nutrients. Received: 9 July 1997 / Accepted: 15 September 1997  相似文献   
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