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991.

Objective

To investigate the relation between donor characteristics and TRALI incidence.

Background

Transfusion-related acute lung injury (TRALI) is a potentially fatal complication of transfusion. In pre-clinical studies and several clinical studies, TRALI has been related to loss of product quality during red blood cell (RBC) storage, called the “storage lesion”. Donor characteristics, as for example age, genetics and life style choices influence this “storage lesion”. We hypothesized that donor sex, age and blood type is related to TRALI incidence.

Methods/materials

We performed a secondary analysis of two cohort studies, designed to identify TRALI risk factors by matching TRALI patients to transfused controls. We obtained donor sex, age and blood type from the Dutch Blood Bank Sanquin and investigated TRALI incidence in patients who were exposed to a certain donor characteristic. We used Kruskal-Wallis testing to compare the number of transfused products and Chi2 testing to compare proportions of TRALI patients and transfused control.

Results

After implementation of the male-donor only plasma strategy, patients received more transfusion products from male donors. However, we did not detect a relation between TRALI incidence and donor sex. Both TRALI patients and transfused controls received mainly products from donors over 41 years old, but donor age did not influence TRALI risk. Donor blood type, the transfusion of blood type-compatible and blood type-matched products also had no influence on TRALI incidence.

Conclusion

We conclude that in two cohorts of TRALI patients, donor age, donor sex and donor blood type are unrelated to TRALI.  相似文献   
992.
Schrander-Stumpel C, de Die-Smulders C, de Krom M, Schyns-Fleuren S, Hamel B, Jaeken D, Fryns J-P. Marden-Walker syndrome: case report, literature review and nosologic discussion.
Clin Genet 1993: 43: 303–308. © Munksgaard, 1993
The Marden-Walker syndrome is characterized by psychomotor retardation, a mask-like face with blepharophimosis, micrognathia and a high-arched or cleft palate, low-set ears, kyphoscoliosis and joint contractures. We report on a male patient with the clinical features of the syndrome. In addition, he had a Dandy-Walker malformation with hydrocephalus and vertebral abnormalities. During pregnancy, there were feeble fetal movements and polyhydramnios. We propose that Marden-Walker syndrome is one of the etiologic possibilities in children with the heterogeneous fetal a(hypo)kinesia deformation sequence (FADS). Differential diagnosis is discussed. The etiology is probably heterogeneous.  相似文献   
993.
Familial lipoprotein lipase deficiency (FLD) is of particular interest to the French Canadian population of Québec since the largest concentration of homozygotes and carriers of this genetic disease in the world resides in this area. We have previously described a missense mutation (M-188) in the lipoprotein lipase (LPL) gene which was present in FLD patients belonging to different ancestries, including a number of French Canadians (Monsalve MV et al. J Clin Invest 1990: 86: 728-734). In the present report, we show that this mutation, although found in largest absolute numbers among French Canadians as compared to other groups in the world, accounts for only a small proportion (24%) of all the LPL mutant alleles in this population. The M-188 occurs either in the homozygote state or as a compound heterozygote with another LPL mutation. Analysis of geographic distribution indicates that the M-188 is more prevalent in western Québec, with the highest carrier rate in the Mauricie region. Genealogical reconstruction leads to the recognition of four founders for M-188, all emigrants from France to Québec in the 17th century.  相似文献   
994.
Summary A young man who had suffered several episodes of deep-vein thrombosis of the legs since the age of 20 had a myocardial infarction at the age of 33, at which time both a prolonged partial thromboplastin time (PTT), compatible with a lupus anticoagulant (LA), and decreased fibrinolytic capacity (FC) were found.His sister presented with deep-vein thrombosis of a leg and subsequent pulmonary embolism when she was 18 years old. She had a miscarriage three years later and developed a hemolytic-uremic syndrome at the age of 35. The PT and FC were normal. Laboratory investigations of the parents revealed positive antinuclear antibodies in the mother's serum but no anomaly in the father.This study suggests a familial tendency to develop autoimmune disorders associated with LA and thromboembolic complications related to decreased FC.  相似文献   
995.
BACKGROUND: Apple allergy is dominated by IgE antibodies against Mal d 1 in areas where birch pollen is endemic. Apples with significantly decreased levels of Mal d 1 would allow most patients in these areas to eat apples without allergic reactions. OBJECTIVE: The aim of this study was to inhibit the expression of Mal d 1 in apple plants by RNA interference. METHODS: In vitro -grown apple plantlets were transformed with a construct coding for an intron-spliced hairpin RNA containing a Mal d 1-specific inverted repeat sequence separated by a Mal d 1-specific intron sequence. The presence of the construct in transformants was checked by PCR. Expression of Mal d 1 in leaves was monitored by prick-to-prick skin testing in 3 patients allergic to apples and by immunoblotting with a Mal d 1-reactive mAb and with IgE antibodies against Mal d 1. RESULTS: After transformation, plantlets were selected on the basis of having a normal phenotype and growth rate. With PCR, in 6 of 9 selected plantlets, the presence of the gene-silencing construct was demonstrated. By skin prick test it was shown that a wild-type plantlet had significantly ( P < .05) higher allergenicity than 5 of the transformants. Reduction of expression of Mal d 1 was confirmed by immunoblotting. In wild-type and unsuccessful transformants, a strong band was detected with Mal d 1-reactive mAb 5H8 at the expected apparent M r of 17 kDa. This band was virtually absent in the transformants that carried the gene-silencing construct. With human IgE antibodies, the same observations were made. CONCLUSIONS: Mal d 1 expression was successfully reduced by RNA interference. This translated into significantly reduced in vivo allergenicity. These observations support the feasibility of the production by gene silencing of apples hypoallergenic for Mal d 1.  相似文献   
996.
Stress proteins as inducers and targets of regulatory T cells in arthritis   总被引:2,自引:0,他引:2  
Immunization with microbial or mammalian stress proteins or heat-shock proteins in models of experimental autoimmunity has been observed to lead to increased disease resistance. Furthermore, such immunization has been proposed to result in the induction and expansion of T cells that suppress disease upon transfer. Comparisons of microbial heat-shock proteins with other conserved immunogenic proteins of bacterial origin have indicated a unique capacity for heat-shock proteins to induce a regulatory phenotype in T cells, such as reflected by the production of IL10. Also, studies in children with chronic arthritis have indicated that T-cell responses to heat-shock proteins are associated with a benign course of the disease and with remission. Furthermore, in patients, heat-shock-protein-(HSP-) activated T cells were shown to display regulatory phenotypes consistent with CD4+ CD25+ T regulatory cells.  相似文献   
997.
BACKGROUND: Anti-Müllerian hormone (AMH), produced by growing pre-antral and early antral ovarian follicles, has been shown to be a useful marker for ovarian ageing. Serum AMH concentrations are elevated during reproductive life in anovulatory women, especially in those patients exhibiting polycystic ovaries (PCO). The current study was designed to investigate whether the decrease in AMH serum concentrations over time is different comparing women with normogonadotrophic anovulation [World Health Organization (WHO) group 2 (including polycystic ovary syndrome (PCOS)] and normo-ovulatory controls. METHODS AND RESULTS: AMH serum levels were assessed on two occasions in 98 patients suffering from WHO 2 anovulatory infertility as well as in 41 normo-ovulatory premenopausal women. Median time interval between both visits was 2.6 years (range 0.3-9.0) for WHO 2 patients compared with 1.6 years (range 1.0-7.3) in controls. Serum AMH concentrations were significantly (P < 0.0001) elevated on both occasions in WHO 2 patients (AMH1, median = 7.5 microg/l, range 0.1-35.8; and AMH2, median = 6.7 microg/l, range 0.0-30.6) compared with controls (AMH1, median = 2.1 microg/l, range 0.1-7.4; and AMH2, median = 1.3 microg/l, range 0.0-5.0). Regression analysis, corrected for age, indicated a significant relative decrease in serum AMH concentrations over time for both groups (P < 0.001). However, the decline in serum AMH in WHO 2 patients was significantly less compared with controls (P = 0.03). CONCLUSION: The present longitudinal study shows that serum AMH concentrations decrease over time both in women presenting with WHO 2 anovulatory infertility and in normo-ovulatory controls. The decrease in WHO 2 patients is less pronounced despite distinctly elevated concentrations. This observation may suggest retarded ovarian ageing and hence a sustained reproductive life span in these patients.  相似文献   
998.
We tested whether auditory sequences of beeps can modulate the tactile perception of sequences of taps (two to four taps per sequence) delivered to the index fingertip. In the first experiment, the auditory and tactile sequences were presented simultaneously. The number of beeps delivered in the auditory sequence were either the same as, less than, or more than the number of taps of the simultaneously presented tactile sequence. Though task-irrelevant (subjects were instructed to focus on the tactile stimuli), the auditory stimuli systematically modulated subjects tactile perception; in other words subjects responses depended significantly on the number of delivered beeps. Such modulation only occurred when the auditory and tactile stimuli were similar enough. In the second experiment, we tested whether the automatic auditory-tactile integration depends on simultaneity or whether a bias can be evoked when the auditory and tactile sequence are presented in temporal asynchrony. Audition significantly modulated tactile perception when the stimuli were presented simultaneously but this effect gradually disappeared when a temporal asynchrony was introduced between auditory and tactile stimuli. These results show that when provided with auditory and tactile sensory signals that are likely to be generated by the same stimulus, the central nervous system (CNS) tends to automatically integrate these signals.  相似文献   
999.
Recent studies reported differential information in human magnetocardiogram and in electrocardiogram. Vortex currents have been discussed as a possible source of this divergence. With the help of physical phantom experiments, we quantified the influence of active vortex currents on the strength of electric and magnetic signals, and we tested the ability of standard source localization algorithms to reconstruct vortex currents. The active vortex currents were modeled by a set of twelve single current dipoles arranged in a circle and mounted inside a phantom that resembles a human torso. Magnetic and electric data were recorded simultaneously while the dipoles were switched on stepwise one after the other. The magnetic signal strength increased continuously for an increasing number of dipoles switched on. The electric signal strength increased up to a semicircle and decreased thereafter. Source reconstruction with unconstrained focal source models performed well for a single dipole only (less than 3-mm localization error). Minimum norm source reconstruction yielded reasonable results only for a few of the dipole configurations. In conclusion active vortex currents might explain, at least in part, the difference between magnetically and electrically acquired data, but improved source models are required for their reconstruction.  相似文献   
1000.
Adverse drug reactions and ineffective drug treatment are responsible for a large health care burden. Considerable variability in drug response makes the prediction of the individual reaction difficult. Pharmacogenetics can help to individualize drug treatment in accordance with the genetic make-up of the patient. Drug response is best understood as a complex interplay between pharmacokinetics, pharmacodynamics, and other disease-associated factors. There are a large number of genetic variants in the enzymes of phase I and phase II drug metabolism, in drug transporters, and drug targets, all of which account for differences in drug response. The polymorphisms in the cytochrome P450 enzyme system have been investigated most extensively. Genotype-based dose adjustment which should ensure "bioequivalent" drug concentrations in all patients has been derived from pharmacokinetic parameters, but this approach will have to be verified in prospective studies. Drug transport has recently been recognized as a further crucial determinant in pharmacokinetics. The effect of genetics on disease susceptibility and drug treatment has been studied quite extensively; however, hardly any of this progress is at present reflected in routine health care. The integration of pharmacogenetic factors in clinical trials requires novel considerations for study design and data interpretation. It is to be hoped that the new science bioinformatics will (a) help us identify the contribution of genetics to disease and treatment response and will (b) create data-processing devices which help the physician in the face of the enormously expanding scientific knowledge in selecting the best individually adapted treatment for the patient.  相似文献   
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