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1.
Prior to the binding of antigenic peptide, a complex of chaperone proteins associates with the Major Histocompatibility Complex (MHC) class I heavy chain/β2m heterodimer. Although each dornain of the MHC class I heavy chain contains amino acid resid uses that influence chaperone binding, there are several pieces of evidence that point to an interaction between the MHC clas 1α2/α3 domains and tapasin. In egard to the site on tapasin involved in the tapasin/MHC interface, we have found that a particular region of tapasin (containing amino acid residues 334–342) is necessary for the binding of tapasin to the MHC class I heavy chain. Our results also indicate that amino acids in this region of tapasin also affect the proportion of MHC class I open forms expressed at the cell surface and MHC class I egress from the endoplasmic reticulurn. Based on these results and those obtained by other laboratories, a model for MHC class I/tapasin interaction is proposed.  相似文献   
2.
Approximately 70% of birch pollen allergic patients in Europe experience hypersensitivity reactions to Immunoglobulin E (IgE) cross-reactive food sources. This so-called pollen-food syndrome (PFS) is defined by allergic symptoms elicited promptly by the ingestion of fruits, nuts, or vegetables in these patients. So far, in the literature, less attention has been given to Bet v 1 cross-reactive symptoms caused by pear (Pyrus communis). In the Netherlands, pears are widely consumed. The primary objective of this study was to measure the type and severity of allergic symptoms during pear challenges in birch pollen allergic patients, with a positive history of pear allergy, using two different pear varieties. Fifteen patients were included, skin prick test (SPT), prick-to-prick test (PTP), specific Immunoglobulin E (sIgE), and single-blind oral challenges were performed with two pear (Pyrus communis) varieties: the ‘Cepuna’ (brand name Migo®) and the ‘Conference’ pears. All patients were sensitized to one or both pear varieties. A total of 12 out of 15 participants developed symptoms during the ‘Cepuna’ food challenge and 14/15 reacted during the ‘Conference’ challenge. Challenges with the ‘Cepuna’ pears resulted in less objective symptoms (n = 2) in comparison with challenges with ‘Conference’ pears (n = 7). Although we did not find significance between both varieties in our study, we found a high likelihood of fewer and less severe symptoms during the ‘Cepuna’ challenges. Consequently selected pear sensitized patients can try to consume small doses of the ‘Cepuna’ pear outside the birch pollen season.  相似文献   
3.
Archives of Sexual Behavior - Research on asexuality as a part of the experience of human sexuality has increased over the last two decades. However, there has not yet been a systematic review of...  相似文献   
4.
5.
目的:建立一种快速、有效的血清铜蓝蛋白(CP)筛查方法。方法:醋酸纤维膜电泳分离血清CP,盐酸联苯胺显示法。结果:用此方法可明确检测出Wilson氏病患者血清中CP含量的变化。结论:醋酸纤维膜电泳检测血清CP是一种有效的血清CP筛查方法。  相似文献   
6.
Background : Anti‐muscle specific kinase antibody positive (MuSK Ab) myasthenia gravis (MG) patients are known to have different clinical course compared to anti‐acetylcholine receptor Ab positive MG patients. Therapeutic plasma exchange (TPE) has been reported to be effective; however, little is known of the response and of TPE procedural information. An ASFA Apheresis Registry was developed to analyze those data. Methods : The study collected detailed de‐identified patient data, TPE procedures, and treatment outcome/complications. Collected data was described in aggregate. Results : A total of 15 MuSK Ab MG patients with exacerbation of MG symptoms, 13 females/2 males, median age 44, were investigated. Thirty TPE courses (median 5 procedures/course, total 145 procedures) were evaluated. All TPE procedures were performed with citrate anticoagulation, 1 − 1.25 plasma volume exchange in 100% fluid balance, and 90% of courses used only albumin as replacement. Calcium was added to albumin or given orally as needed. TPE was performed every other day in 55% of courses. Adverse events occurred in 3.4% of procedures. Ten patients (67%) experienced relapses within a median of 7 weeks. Objective symptoms were resolved in more than 75% of courses. Overall subjective improvement rates were 94.1%/93.3% after 3/4 TPE procedures, respectively. Thirty‐one percent of patients responded poorly with minimal recovery. Conclusion : Overall subjective improvement was seen up to 94% of patients after one course of TPE. Some patients were poor‐responders. Five TPE may be adequate for initial course with additional TPE as needed. Based upon this preliminary data, we will modify our future data collection. J. Clin. Apheresis 32:5–11, 2017. © 2016 Wiley Periodicals, Inc.  相似文献   
7.
Neuromyelitis optica (NMO) is a relapsing inflammatory disease of the central nervous system that predominantly affects the spinal cord and optic nerves. The clinical hallmark of the disease is a step‐wise deterioration of visual and spinal cord function. This study reviews patients with steroid resistant relapsing NMO presenting for therapeutic plasma exchange (TPE) at our institution from December 2005 to December 2012. A total of five patients were treated with single volume TPE. Both subjective and objective clinical response to TPE was estimated by three different sources (the patient, a Transfusion Medicine physician, and the treating Neurologist) with the patient and Transfusion Medicine physician's final assessment of response made at the time of the last TPE in the series and the treating neurologist's assessment of response made at the time of the next neurological exam after the last TPE. A total of 17 TPE series were performed with the average course of therapy being three series (ranged 1–5) with five TPE (ranged 3–7) per series. All patients demonstrated improvement with each series of TPE and all procedures were well tolerated with only transient and well‐described reactions all of which were successfully resolved with minor or no sequelae. J. Clin. Apheresis 29:171–177, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
8.
Wilson's disease (WD) is an autosomal‐recessive disorder of impaired copper metabolism resulting in accumulation of copper primarily in the liver but ultimately in many organs and tissues. A small number of patients with WD initially present with fulminant hepatic failure (FHF), hypercupremia, and intravascular hemolysis. The therapeutic goals for these patients include quickly removing the copper and preparing the patient for liver transplantation. Here, we report on a 6‐year‐old male with WD in FHF with anemia, renal insufficiency, and coagulopathy. The patient received a series of therapeutic plasma exchanges (TPE) as adjunctive therapy to remove copper and stabilize his coagulopathy and anemia until a transplant was possible. A total of five single plasma volume (1500 mL) TPE were performed over the course of 11 days with plasma as the replacement fluid. Laboratory results demonstrated temporary improvement after each procedure. Liver transplantation was performed 12 days after beginning TPE and 35 days after admission to the hospital. TPE was a successful adjunctive therapy to bridge this patient with WD to transplantation. J. Clin. Apheresis 27:282–286, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
9.
We recently concluded that exposure to solvent-contaminated drinking water was an unlikely explanation for observed excesses of adverse pregnancy outcomes during 1980–1981 in the Los Paseos neighborhood of Santa Clara County, California, because these excesses were not observed in an adjacent exposed area. The validity of this conclusion depends on the assumption that the two areas had comparable exposure. Using quantitative methods to model movement of the solvent leak plume and water flow within the distribution system, we estimated that women with adverse outcomes were no more likely to have received contaminated water than women with normal live births. These results strengthen the conclusion that exposures to water from the contaminated well were not responsible for the excess of adverse outcomes observed in the Los Paseos area.  相似文献   
10.

Background

To delineate the early progression of autism spectrum disorder (ASD) symptoms, this study investigated developmental characteristics of infants at high familial risk for ASD (HR), and infants at low risk (LR).

Methods

Participants included 210 HR and 98 LR infants across 4 sites with comparable behavioral data at age 6, 12, and 24 months assessed in the domains of cognitive development (Mullen Scales of Early Learning), adaptive skills (Vineland Adaptive Behavioral Scales), and early behavioral features of ASD (Autism Observation Scale for Infants). Participants evaluated according to the DSM-IV-TR criteria at 24 months and categorized as ASD-positive or ASD-negative were further stratified by empirically derived cutoff scores using the Autism Diagnostic Observation Schedule yielding four groups: HR-ASD-High, HR-ASD-Moderate (HR-ASD-Mod), HR-ASD-Negative (HR-Neg), and LR-ASD-Negative (LR-Neg).

Results

The four groups demonstrated different developmental trajectories that became increasingly distinct from 6 to 24 months across all domains. At 6 months, the HR-ASD-High group demonstrated less advanced Gross Motor and Visual Reception skills compared with the LR-Neg group. By 12 months, the HR-ASD-High group demonstrated increased behavioral features of ASD and decreased cognitive and adaptive functioning compared to the HR-Neg and LR-Neg groups. By 24 months, both the HR-ASD-High and HR-ASD-Moderate groups demonstrated differences from the LR- and HR-Neg groups in all domains.

Conclusions

These findings reveal atypical sensorimotor development at 6 months of age which is associated with ASD at 24 months in the most severely affected group of infants. Sensorimotor differences precede the unfolding of cognitive and adaptive deficits and behavioral features of autism across the 6- to 24-month interval. The less severely affected group demonstrates later symptom onset, in the second year of life, with initial differences in the social-communication domain.

Electronic supplementary material

The online version of this article (doi:10.1186/s11689-015-9117-6) contains supplementary material, which is available to authorized users.  相似文献   
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