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51.
The plasma membrane of the cereal aleurone layer is the site of perception of germination signals and release of enzymes to the starchy endosperm. Analysis of membrane proteins is challenging due to their hydrophobicity and low abundance; thus, little is known about the membrane proteins involved in seed germination. A membrane fraction highly enriched for the plasma membrane H+-ATPase was prepared from barley aleurone layers by aqueous two-phase partitioning. Because detergent and salt washes did not efficiently remove soluble proteins from the membrane preparations, an alternative procedure was developed, comprising batch reversed-phase chromatography with stepwise elution of hydrophobic proteins by 2-propanol. Proteins in the most hydrophobic fraction were separated by SDS-PAGE and identified by LC-MS/MS and barley EST sequence database search. The method was efficient for enrichment of integral membrane proteins with relatively low levels of soluble contaminating proteins. Forty-six proteins associated with barley aleurone plasma membranes were identified, including proteins with more than 10 transmembrane domains. Among the identified proteins were two new isoforms of the plasma membrane H+-ATPase, two proteins possibly involved in ion-channel regulation, and two proteins of unknown function. This represents the first analysis of membrane proteins involved in seed germination using a proteomics approach. 相似文献
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53.
Hölmich LR Kjøller K Fryzek JP Høier-Madsen M Vejborg I Conrad C Sletting S McLaughlin JK Breiting V Friis S 《Plastic and reconstructive surgery》2003,111(2):723-32; discussion 733-4
Epidemiologic evidence does not support an association between silicone breast implants and connective tissue or other rheumatic diseases. However, a recent study has suggested that women with ruptured implants may be at increased risk of developing fibromyalgia. An analysis of adverse health outcomes according to breast implant rupture status was conducted in 238 unselected Danish women with cosmetic silicone breast implants. Ninety-two of the women had definite implant rupture, and 146 had intact implants as determined by magnetic resonance imaging. Before undergoing imaging, the women provided blood samples and completed a self-administered questionnaire. Women with ruptured implants overall, and the subgroup with extracapsular ruptures (n = 23), were compared with women with intact implants regarding a number of self-reported diseases and symptoms and the presence of specific autoantibodies, such as antinuclear antibodies, rheumatoid factor, and cardiolipin immunoglobulin G and M antibodies. Overall, there were no differences in the occurrence of self-reported diseases or symptoms or in the presence of autoantibodies between women with intact implants and women with ruptured implants, including extracapsular rupture. The only exception was capsular contracture, which was reported six times more frequently by women with extracapsular ruptures than by women with intact implants (OR, 6.3; 95 percent CI, 1.7 to 23.5). In conclusion, this study of unselected women with silicone breast implants could establish no association between silicone implant rupture and specific diseases or symptoms related to connective tissue disease or other rheumatic conditions, except for an excess of capsular contracture among women with extracapsular rupture. 相似文献
54.
Long-term effects of polyacrylamide hydrogel on human breast tissue 总被引:23,自引:0,他引:23
Christensen LH Breiting VB Aasted A Jørgensen A Kebuladze I 《Plastic and reconstructive surgery》2003,111(6):1883-1890
Polyacrylamide hydrogel is an atoxic, stable, nonresorbable sterile watery gel consisting of approximately 2.5% cross-linked polyacrylamide and nonpyrogenic water. Polyacrylamide hydrogel is widely used in ophthalmic operations, drug treatment, food packaging products, and water purification. In the former Soviet Union, polyacrylamide hydrogel has been used in plastic and aesthetic surgery for more than 10 years, and Kiev City Hospital treats approximately 300 women a year for breast augmentation using the polyacrylamide hydrogel Interfall (Contura SA, Montreux, Switzerland). Capsule shrinkage following these injections has never been observed. The authors examined breast tissue samples from a total of 27 women who had polyacrylamide hydrogel injected at Kiev City Hospital up to 8 years and 10 months earlier. Age at operation, duration of polyacrylamide hydrogel implantation, history of possible side effects to the gel injection, other intercurrent diseases, the reason for present open breast operation, and breast palpation findings before operation were in each case compared with the histological findings on samples taken from breast tissue bordering the gel. The gel presented itself as a dark violet, homogenous mass with a rounded or ragged outline in large or medium-size deposits and as elongated strands, which mimicked the extracellular matrix, in small deposits. Histological findings of the breast tissue bordering the gel showed three different patterns: large collections of gel gave rise to a thick, soft-looking cellular membrane of macrophages and foreign-body giant cells; medium-size deposits were surrounded by just a thin layer of macrophages; and small deposits were not associated with any reaction in the surrounding tissue. Projections of the cellular soft membrane, known as granulomas, were seen in six patients. The granulomas were composed of macrophages, foreign-body giant cells, lymphocytes, and blood cells. A thin layer of fibrous connective tissue was occasionally present around the foreign-body membrane, but the thick fibrous capsule, which has been described in connection with silicone implants, was completely absent. The gel changes could be correlated to neither time since gel injection nor a history of recent injury or inflammation. It is concluded that the polyacrylamide hydrogel Interfall, which has been used in the former Soviet Union, is stable over time, nondegradable, confined to the breast, and diffusion and migration resistant. When the hydrogel is injected in medium-size or large quantities a cellular foreign-body reaction occurs, but in small amounts it is capable of splitting up individual connective tissue fibers and fat cells, substituting for the extracellular connective tissue matrix without eliciting any foreign-body reaction. As far as these data are concerned, polyacrylamide hydrogel is well tolerated by the breast and does not give rise to severe fibrosis, pain, or capsule shrinkage. However, to determine safety with more certainty, a larger sample size would be necessary. 相似文献
55.
OBJECTIVE: To evaluate the intraoperative imprint diagnoses of smears from sentinel lymph nodes that had been primary screened by cytotechnologists and to assess the most important causes of false negative (FN) imprint diagnoses. STUDY DESIGN: Material consisted of 429 imprints from sentinel lymph nodes in 211 breast cancer patients that were sent for frozen section examination over 13 months. RESULTS: The mean number of imprints/lymph nodes per patient was 2.02. The mean screening time per imprint was 3.6 minutes. Sixty-six sentinel nodes (16%) from 51 women (24%) were metastatic. Imprints and/or frozen sections were positive in 54 nodes (82%). Imprints were positive in 38 nodes, representing 70% of intraoperative positive nodes and 58% of the total number of positive nodes. Twenty-six of 28 (93%) FN imprints were due to suboptimal sampling. Four of 9 FN macrometastases did not contain diagnostic or suspicious cells/cell groups even on rescreening, whereas a few, and then only 1 diagnostic group were identified in 2/9. There were no false positives. CONCLUSION: Primary screening by experienced cytotechnologists is both rapid and reliable and enabled the diagnosing pathologist to concentrate on the frozen section. The major cause of false negative imprints is sampling, even in macrometastases. 相似文献
56.
Schrohl AS Christensen IJ Pedersen AN Jensen V Mouridsen H Murphy G Foekens JA Brunner N Holten-Andersen MN 《Molecular & cellular proteomics : MCP》2003,2(3):164-172
The purpose of this study was to investigate the association between tumor tissue levels of total tissue inhibitor of metalloproteinases-1 (TIMP-1) and prognosis in patients with primary breast cancer and to analyze whether measurement of TIMP-1 in tumor extracts added prognostic information to that obtained from measurements of urokinase-type plasminogen activator and plasminogen activator inhibitor type 1 (PAI-1). An established sandwich enzyme-linked immunosorbent assay was thoroughly validated for the measurement of total TIMP-1 in tumor tissue extracts and used to determine levels of total TIMP-1 in 341 detergent-extracted tumor tissue samples from patients with primary breast cancer. The median age of the patients was 56 years (range, 29-75 years), and 164 were lymph node-negative, and 177 were lymph node-positive. The median follow-up time of the patients was 8.5 years (range, 7.3-11.3 years), and during follow-up 153 patients experienced recurrence of disease, and 136 patients died. In univariate survival analysis, we found a significant association between tumor tissue TIMP-1 level and both shorter recurrence-free survival (p = 0.0004) and shorter overall survival (p = 0.03). In multivariate survival analysis, higher tumor tissue TIMP-1 levels significantly and independently predicted shorter recurrence-free survival (p < 0.05, hazard ratios >1, comparing quartiles II-IV with I). In addition, we found that measurement of TIMP-1 levels added prognostic information to that obtained from measurement of PAI-1. In conclusion, high levels of TIMP-1 in tumor tissue extracts are significantly associated with a poor prognosis in patients with primary breast cancer. Furthermore TIMP-1 adds prognostic information to that obtained from PAI-1. However, further validation in independent data sets is needed. 相似文献
57.
Vibeke Ravn Christence Stubbe Teglbjærg Ulla Mandel Erik Dabelsteen 《Cell and tissue research》1992,270(3):425-433
Summary The blood group ABO(H) determinants are major allogenic antigens in both erythrocytes and tissue of man. These antigens and related carbohydrates are markers of cellular maturation and differentiation in many epithelial tissues and have recently attracted great interest as tumor-associated antigens. Previous studies of endometrial tissues have indicated that glycosylation in this tissue may be related to hormonal stimulation. We have investigated the immunohistochemical distribution of type-2 chain histo-blood group-related carbohydrates in specimens of normal, cycling endometria obtained from hysterectomies on women with known ABO/Lewis erythrocyte type and saliva secretor status. N-acetyllactosamine and Lex were demonstrated to be uninfluenced by the genetic background. A and Aley antigens were exclusively demonstrated in endometria from blood group A individuals, while Ley was expressed in endometria from blood group 0 individuals mainly. The precursor N-acetyllactosamine as well as the terminal H, A, and ALey antigens were shown in only a few cells. In contrast, N-acetyllactosamine substituted by sialic acid and/or fucose residues (Lex, sialosyl-Lex, Ley) were demonstrated in epithelial cells of normal, cycling endometrium, but with both quantitative and qualitative differences in staining relating to the menstrual cycle, indicating that type-2 chain antigens are expressed under both genetic and hormonal influence in human cycling endometrium. 相似文献
58.
Henrik Friis Bernardette Cichon Christian Fabiansen Ann-Sophie Iuel-Brockdorff Charles W. Yamogo Christian Ritz Ruth Frikke-Schmidt Andr Briend Kim F. Michaelsen Vibeke B. Christensen Suzanne Filteau Mette F. Olsen 《PLoS medicine》2022,19(3)
BackgroundAmong children with moderate acute malnutrition (MAM) the level of serum cobalamin (SC) and effect of food supplements are unknown. We aimed to assess prevalence and correlates of low SC in children with MAM, associations with hemoglobin and development, and effects of food supplements on SC.Methods and findingsA randomized 2 × 2 × 3 factorial trial was conducted in Burkina Faso. Children aged 6 to 23 months with MAM received 500 kcal/d as lipid-based nutrient supplement (LNS) or corn–soy blend (CSB), containing dehulled soy (DS) or soy isolate (SI) and 0%, 20%, or 50% of total protein from milk for 3 months. Randomization resulted in baseline equivalence between intervention groups. Data on hemoglobin and development were available at baseline. SC was available at baseline and after 3 and 6 months. SC was available from 1,192 (74.1%) of 1,609 children at baseline. The mean (±SD) age was 12.6 (±5.0) months, and 54% were females. Low mid-upper arm circumference (MUAC; <125 mm) was found in 80.4% (958) of the children and low weight-for-length z-score (WLZ; <−2) in 70.6% (841). Stunting was seen in 38.2% (456). Only 5.9% were not breastfed. Median (IQR) SC was 188 (137; 259) pmol/L. Two-thirds had SC ≤222 pmol/L, which was associated with lower hemoglobin. After age and sex adjustments, very low SC (<112 pmol/L) was associated with 0.21 (95% CI: 0.01; 0.41, p = 0.04) and 0.24 (95% CI: 0.06; 0.42, p = 0.01) z-score lower fine and gross motor development, respectively.SC data were available from 1,330 (85.9%) of 1,548 children followed up after 3 months and 398 (26.5%) of the 1,503 children after 6 months. Based on tobit regression, accounting for left censored data, and adjustments for correlates of missing data, the mean (95% CI) increments in SC from baseline to the 3- and 6-month follow-up were 72 (65; 79, p < 0.001) and 26 (16; 37, p < 0.001) pmol/L, respectively. The changes were similar among the 310 children with SC data at all 3 time points. Yet, the increase was 39 (20; 57, p < 0.001) pmol/L larger in children given LNS compared to CSB if based on SI (interaction, p < 0.001). No effect of milk was found. Four children died, and no child developed an allergic reaction to supplements. The main limitation of this study was that only SC was available as a marker of status and was missing from a quarter of the children.ConclusionsLow SC is prevalent among children with MAM and may contribute to impaired erythropoiesis and child development. The SC increase during supplementation was inadequate. The bioavailability and adequacy of cobalamin in food supplements should be reconsidered.Trial registrationISRCTN Registry ISRCTN42569496.Henrik Friis and colleagues, investigate the prevalence and correlates of low serum cobalamin, associations with hemoglobin and child development, and associations of serum cobalamin levels with food supplementation in children moderate acute malnutrition in Burkina Faso. 相似文献
59.
Association between asthma-related phenotypes and the CC16 A38G polymorphism in an unselected population of young adult Danes 总被引:4,自引:0,他引:4
Candelaria PV Backer V Laing IA Porsbjerg C Nepper-Christensen S de Klerk N Goldblatt J Le Souëf PN 《Immunogenetics》2005,57(1-2):25-32
The gene for Clara cell 16-kDa (CC16) protein is a promising candidate for asthma susceptibility. The CC16 38A allele has been associated with decreased CC16 plasma levels and increased incidence of asthma in Australian children. To date these results have not been replicated in adults. Therefore, potential links between CC16 A38G, asthma and atopy were investigated in an unselected population of young adult Danes. Four hundred sixty-four Danes, aged 19–29 years, from Copenhagen participated in an asthma and allergy phenotype–genotype study. Genotyping was done by Sau96I restriction digestion of PCR products spanning the A38G polymorphism. Potential A38G genotype and asthma-related phenotype associations were investigated using regression analysis, adjusting for potential confounders where appropriate. Adults with the 38AA genotype had higher odds of current asthma (OR 3.2, P=0.013) and ever asthma (OR 2.2, P=0.045) compared with those with the 38GG genotype. Adjusting for atopy had minimal effect on this relationship. A positive linear trend was evident between the 38A allele and atopic dermatitis (OR 1.67, P=0.02). No associations were found between the A38G polymorphism and rhinitis, atopy, forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), airway responsiveness (AR) to histamine or peripheral blood eosinophil level (PBEL). An atopy-independent association between CC16 38AA and asthma prevalence was identified, suggesting the CC16 38A allele predisposes to adult asthma independent of Th1/Th2 processes. This finding is consistent with previous studies in children, but is the first reported association between CC16 A38G and asthma in adults. CC16 38A also displayed a positive linear trend with atopic dermatitis. 相似文献
60.