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1.
BACKGROUND: The major allergen of the dust mite Lepidoglyphus destructor, Lep d 2, has been produced as a recombinant allergen (rLep d 2) with IgE reactivity both in vivo and in vitro. A modified form of rLep d 2 (rLep d 2.6Cys) obtained by site-directed mutagenesis has been shown to have a reduced IgE reactivity in vitro. In this study we have compared the ability of rLep d 2 and rLep d 2.6Cys to elicit positive skin prick tests and cellular responses among L. destructor-sensitized subjects. METHODS: Seventeen subjects were skin prick-tested with rLep d 2, rLep d 2.6Cys, histamine and negative controls and 17-20 h later skin biopsy specimens were taken from the skin prick-tested sites. The biopsy specimens were stained immunohistochemically for EG2+, CD3+, CD1a+, mast cell tryptase+, and IgE+ cells. Dermal cell infiltrates were judged in hematoxylin and eosin staining. Total IgE and allergen-specific IgE were determined by CAP-RAST. RESULTS: Compared to rLep d 2, rLep d 2.6Cys induced significantly smaller and fewer skin prick test reactions (p < 0.001) and dermal cell infiltrates (p < 0.05). Further, rLep d 2.6Cys induced fewer EG2+ cells (p < 0.001) but more tryptase+ cells (p < 0.05) than rLep d 2. A positive RAST to rLep d 2 was obtained for 88.2% of the subjects, while only 35.2% displayed a positive RAST to rLep d 2.6Cys. CONCLUSION: This study demonstrates that rLep d 2.6Cys is less able to evoke IgE-mediated reactions and cellular responses, as measured both in skin and in serum, than rLep d 2. In the future this hypoallergenic derivative may be a promising candidate molecule for immunotherapy of L. destructor-allergic patients.  相似文献   
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Cell cycle regulators cdc27 and securin participate in control of the mitotic checkpoint and survey the mitotic spindle to maintain chromosomal integrity. This is achieved by their functions in metaphase–anaphase transition, DNA damage repair, enhancement of mitotic arrest and apoptosis. We report on the roles of cdc27 and securin in aneuploidy and prognosis of breast cancer. The study comprises 429 breast cancer patients with up to 22 years of follow‐up. DNA content was determined by image cytometry, and immunopositivity for cdc27 and securin was based on tissue microarrays. An inverse association between cdc27 and securin expression was observed in both image cytometric and immunohistochemical analyses. Low cdc27 and high securin expression identified patients with significant difference in disease outcome. Cdc27 and securin immunoexpression identified patients at risk of early cancer death within five years from diagnosis. In multivariate analysis, the combination of cdc27 and securin immunohistochemistry was the strongest predictor of cancer death after lymph node status. We demonstrate, for the first time in human breast cancer, the prognostic value of cdc27 and securin immunohistochemistry. Cdc27 and securin appear promising biomarkers for applications in predicting disease progression, prognostication of individual patients and potential in anti‐mitotic drug development.  相似文献   
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PurposePathological vascular differentiation in retinal vein occlusion (RVO)-related neovessel formation remains poorly characterized. The role of intraocular lymphatic-like differentiation or endothelial progenitor cell activity has not been studied in this disease.MethodsVitrectomy was performed in an eye with hemi-RVO; the neovessel membrane located at the optic nerve head was removed and subjected to immunohistochemistry. Characterization of the neovascular tissue was performed using hematoxylin and eosin, α-smooth muscle actin, and the pan-endothelial cell (EC) adhesion molecule CD31. The expression of lymphatic EC markers was studied by lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1), podoplanin (PDPN), and prospero-related homeobox protein 1 (Prox-1). Potential vascular stem/progenitor cells were identified by active cellular proliferation (Ki67) and expression of the stem cell marker CD117.ResultsThe specimen contained blood vessels lined by ECs and surrounded by pericytes. Immunoreactivity for LYVE-1 and Prox-1 was detected, with Prox-1 being more widely expressed in the active Ki67-positive lumen-lining cells. PDPN expression was instead found in the cells residing in the extravascular tissue. Expression of the stem cell markers CD117 and Ki67 suggested vascular endothelial progenitor cell activity.ConclusionsIntraocular lymphatic-like differentiation coupled with progenitor cell activation may be involved in the pathology of neovessel formation in ischemia-induced human hemi-RVO.Key Words: Hemi-retinal vein occlusion, Endothelial progenitor cell, Platelet endothelial cell adhesion molecule 1, Podoplanin, Prospero-related homeobox gene 1, Lymphatic endothelial cell, Lymphatic vessel endothelial hyaluronan receptor 1, Immunohistochemistry, Proliferative diabetic retinopathy, Vascular endothelial stem cell  相似文献   
5.
Oxidized low‐density lipoprotein (OxLDL) plays a crucial role in the development of atherosclerosis. Carbamylated LDL has been suggested to promote atherogenesis in patients with chronic kidney disease. Here we observed that plasma IgG and IgM antibodies to carbamylated epitopes were associated with IgG and IgM antibodies to oxidation‐specific epitopes (ρ = 0·65–0·86, < 0·001) in healthy adults, suggesting a cross‐reaction between antibodies recognizing carbamyl‐epitopes and malondialdehyde (MDA)/malondialdehyde acetaldehyde (MAA) ‐adducts. We used a phage display technique to clone a human Fab antibody that bound to carbamylated LDL and other carbamylated proteins. Anti‐carbamyl‐Fab (Fab106) cross‐reacted with oxidation‐specific epitopes, especially with MDA‐LDL and MAA‐LDL. We showed that Fab106 bound to apoptotic Jurkat cells known to contain these oxidation‐specific epitopes, and the binding was competed with soluble carbamylated and MDA‐/MAA‐modified LDL and BSA. In addition, Fab106 was able to block the uptake of carbamyl‐LDL and MDA‐LDL by macrophages and stained mouse atherosclerotic lesions. The observed cross‐reaction between carbamylated and MDA‐/MAA‐modified LDL and its contribution to enhanced atherogenesis in uraemic patients require further investigation.  相似文献   
6.
Premature adrenarche (PA) refers to an earlier than normal increase in adrenocortical androgen production. The pathogenesis of PA remains largely unknown. We hypothesized that common polymorphisms at P450 oxidoreductase (POR), steroid sulfotransferase (SULT2A1), or 11β-hydroxysteroid dehydrogenase type 1 (HSD11B1) genes could contribute to the polygenic pathogenesis of PA. We performed a case–control study on the polymorphisms rs1057868 at POR, rs182420 at SULT2A1, and rs12086634 at HSD11B1. The study cohort comprised 73 prepubertal children with PA (defined by clinical signs) and 97 age- and gender-matched healthy controls from a Finnish Caucasian population. Genotype distributions and clinical and metabolic phenotypes were determined. The genotype distributions of the polymorphisms were similar between the study groups. No variant was associated with alterations in serum adrenal steroid concentrations. The minor C variant at SULT2A1 was associated with higher serum sex hormone binding globulin (SHBG) concentrations (T/T, n = 64 vs T/C&;C/C, n = 33; mean 94 vs 116 nmol/L; P = .001) and a trend for lower dehydroepiandrosterone sulfate/dehydroepiandrosterone ratios in the controls (P = .06), and with higher plasma total cholesterol concentrations in the PA subjects (T/T, n = 42 vs T/C&;C/C, n = 31; 4.0 vs 4.6 mmol/L; P < .001). The minor G variant at HSD11B1 was associated with lower plasma triglyceride concentration in the controls (T/T, n = 65 vs T/G&;G/G, n = 32; 0.61 vs 0.49 mmol/L; P = .013). Common polymorphisms at POR, SULT2A1 or HSD11B1 were not associated with PA in a Finnish Caucasian population.  相似文献   
7.
INTRODUCTION: We investigated those psychiatric patients whose reason for seeking medical help was primarily a physical condition. Our objectives were to analyse to what extent they suffered from seasonal variation in mood and behaviour during winter, and to examine whether these patients were evenly distributed between the categories of the ICD-10 Classification of Mental and Behavioural Disorders (ICD-10) by their primary diagnosis of mental disorder. METHOD: Patients attending the psychiatric services of a consultation liaison unit were interviewed for diagnosis, and were asked to fill in a questionnaire on seasonal variation in mood and behaviour. RESULTS: Our results suggest that there are many patients fulfilling the criteria based on the Seasonal Pattern Assessment uestionnaire (SPA) for seasonal affective disorder (SAD) or for subsyndromal SAD, not only in the ICD-10 diagnosis category of mood (affective) disorders but also in other disorder categories. CONCLUSION: This observation is of importance to hospital and private clinicians, as it emphasizes the need to assess the clinical picture in detail and to consider treatment alternatives for patients presenting with mental disorder with a seasonal pattern. (Int J Psych Clin Pract 2000; 4:151-154)  相似文献   
8.
In this study, positron emission tomography (PET) imaging with a radioligand to adenosine A2A receptors (A2AR)—a potent regulator of inflammation—was used to gain insight into the molecular alterations in normal-appearing white matter (NAWM) and gray matter (GM) in secondary progressive multiple sclerosis (SPMS). Normal-appearing white matter and GM, despite seeming normal in conventional mangnetic resonance imaging (MRI), are important loci of widespread inflammation, neuronal damage, and source of progressive disability in multiple sclerosis (MS). Dynamic PET imaging using A2AR-specific [11C]TMSX and brain MRI with diffusion tensor imaging were performed to eight SPMS patients and seven healthy controls. Distribution volumes (VT) of [11C]TMSX were analyzed from 13 regions of interest using Logan plot with arterial plasma input. The SPMS patients had significantly increased [11C]TMSX-VT in NAWM compared with controls (mean (s.d.): 0.55 (±0.08) vs. 0.45 (±0.05); P=0.036). Both the increased VT and the decreased fractional anisotropy (FA) in NAWM were associated with higher expanded disability status scale (EDSS) scores (P=0.030 and P=0.012, respectively), whereas the T2-lesion load of SPMS patients did not correlate with EDSS. This study shows, that A2ARs are increased in the brain of SPMS patients, and that [11C]TMSX-PET provides a novel approach to learn about central nervous system pathology in SPMS in vivo.  相似文献   
9.
Objectives:The purpose of this study was to design, validate, and optimize internally standardized real-time quantitative RT-PCR assays and to identify and avoid problems with assay reliability and examine the impact of an exogenous internal standard.Design and methods:The model system consisted of internally standardized quantitative real-time RT-PCR assays specific for PSA and hK2 mRNA based on time-resolved fluorometric detection of lanthanide chelates.Results:Reproducibility was best when large copy numbers (> 5000 per milliliter blood) were analyzed. Addition of an exogenous target-mimicking internal standard had no significant effect on the reproducibility of the method, but increased the calculated copy numbers by an average of 2-fold.Conclusions:We developed an internally standardized, specific and reproducible real-time RT-PCR analysis method for PSA and hK2 mRNA in circulating cells in the bloodstream. Both PSA and hK2 assays are sufficiently sensitive to detect two LNCaP cells per milliliter whole blood.  相似文献   
10.
The change in augmentation index following salbutamol inhalation has been applied to evaluate endothelial function. We examined the contribution of salbutamol‐induced increase in heart rate to the observed decrease in augmentation index. Haemodynamics were recorded using whole‐body impedance cardiography and continuous pulse wave analysis from tonometric radial blood pressure. All subjects (n = 335, mean age 46, body mass index 26, 48% men) were without medications with cardiovascular influences. The effects of salbutamol inhalation (0.4 mg) versus the endothelium‐independent agent nitroglycerin resoriblet (0.25 mg) were examined during passive head‐up tilt, as the haemodynamic influences of these compounds depend on body position. Salbutamol decreased augmentation index by ~3‐4% units in supine and upright positions. Although salbutamol moderately increased cardiac index (+4.5%) and decreased systemic vascular resistance (?8.5%), the significant haemodynamic explanatory factors for decreased augmentation index in multivariate analysis were increased supine heart rate, and increased upright heart rate and decreased ejection duration (< 0.001 for all, r= 0.36–0.37). Sublingual nitroglycerin decreased supine and upright augmentation index by ~15% units and ~23% units, respectively. The haemodynamic explanatory factors for these changes in multivariate analysis were increased heart rate, reduced ejection duration and reduced systemic vascular resistance ( 0.021 for all, r2 = 0.22–0.34). In conclusion, the lowering influence of salbutamol on augmentation index may be largely explained by increased heart rate, suggesting that this effect may not predominantly reflect endothelial function.  相似文献   
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