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71.
Statins are known to inhibit signaling of Ras superfamily GTPases and reduce T cell adhesion to ICAM-1. Here, we address the hypothesis that statins affect T cell adhesion and migration by modulating the function of specific GTPases. Statins inhibit the synthesis of mevalonic acid, which is required for farnesyl and geranylgeranyl isoprenoid synthesis. Ras superfamily GTPases are post-translationally isoprenylated to facilitate their anchorage to membranes, where they function to stimulate signal transduction processes. We demonstrate that 1 μM statin inhibits the adhesion, migration, and chemotaxis of the T-ALL cell line CCRF-CEM and TEM of CCRF-CEM and PEER T-ALL cells, but higher statin concentrations are needed to inhibit adhesion of primary T cells. Similar effects are observed following treatment with GGTI-298 or RNA interference-mediated knockdown of Rap1b but not Rap1a, Rac1, Rac2, RhoA, or Cdc42. Statins also alter Rap1 activity and Rap1b localization. Rap1 levels are higher in primary T cells than T-ALL cells, which could explain their reduced sensitivity to statins. These results demonstrate for the first time that the closely related Rap1a and Rap1b isoforms have different functions and suggest that statins or Rap1b depletion could be used to reduce tissue invasion in T-ALL.  相似文献   
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73.

Research question

Conventional treatments are often associated with adverse effects and endometriosis pain symptoms may reoccur despite treatment. Consequently, many women use complementary health approaches (CHA) and home remedies (HR) to relieve their pain. The aim of this study was to examine the frequency and the subjectively perceived efficacy of CHA/HR use by women affected by endometriosis.

Design

Retrospective evaluation using medical charts and a questionnaire. Women recruited in hospitals and in self-help groups were asked about the use of ‘topical heat’, ‘repose/relaxation’, ‘movement/massages’, ‘homeopathy/phytotherapy’, ‘acupuncture/traditional Chinese medicine (TCM)’ and ‘kinesiology/physiotherapy’.

Results

From a total of 574 women with a confirmed diagnosis of endometriosis, 359 (62.5%) applied some form of CHA/HR. Women suffering from fatiguing disease symptoms more often selected alternative therapies (odds ratio [OR] 3.14, 95% confidence interval [CI] 1.39–7.11, P?=?0.006) compared with women without these characteristics. Furthermore, women dissatisfied with healthcare provided by their treating physician, more frequently (OR 2.30, 95% CI 1.19–4.45, P?=?0.013) chose the aforementioned alternative strategies.

Conclusion

As conventional therapies may not be sufficiently effective, women's needs should be closely examined, and individual treatment options should be discussed and initiated by clinicians to provide the best comprehensive treatment possible for endometriosis.  相似文献   
74.
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has become a powerful and widespread analytical tool in all fields of life science. Compared with other techniques, its high accuracy and sensitivity makes it a superior method, especially for the analysis of nucleic acids. Recent problems in the analysis of nucleic acids by MALDI-TOF MS can be solved using an automated MALDI-compatible sample-preparation system. Together with the reliable minisequencing assay, high-throughput genotyping of single nucleotide polymorphisms by MALDI-TOF MS is able to become a routine method in research, clinical genetics and diagnostics.  相似文献   
75.
Saposin C is a biological activator of acid beta-glucosidase (GCase), the lysosomal hydrolase with activity towards glucosylceramide (GC). In addition, saposin C possesses a functional domain that determines the in vitro and ex vivo neuritogenic effects of prosaposin, the precursor of saposins A, B, C, and D. The domains for enzymatic activation and neuritogenic function segregate in vitro, respectively, to the carboxyl- and amino-terminal halves of human and mouse saposin C. A chimeric mouse saposin C(1-8)B(8-28)C(30-80) was created to obliterate the neuritogenic region by substituting amino acids 9-29 of saposin C with amino acids 8-28 of saposin B. This saposin showed normal in vitro enzymatic activation effects toward GCase, but no neuritogenic activity. An altered prosaposin was made to contain the chimeric saposin C region. Expression of this altered or wild-type prosaposin was driven by the PGK-1 promoter as a transgene in prosaposin knock-out mice. In cultured fibroblasts from such mice, expressed saposins localized to the lysosomal compartments. Metabolic lipid labeling using L-[3-(14)C]serine showed retention or clearance of GC in prosaposin deficient or transgene reconstituted cells, respectively. In addition, sulfatide catabolism, that requires saposin B and arylsulfatase, was also normalized in prosaposin KO cells reconstituted with the transgenes. These data show that the transgenic prosaposins were expressed and processed to functional saposins in fibroblasts. These results also show that the enzymatic activation domain is located at carboxyl-terminal half of saposin C and functions only in the context of the general saposin structure.  相似文献   
76.
Sturgeons constitute a family of living "fossil" fish whose heart is related to that of other ancient fish and the elasmobranches. We have undertaken a systematic study of the structure of the sturgeon heart aimed at unraveling the relationship between the heart structure and the adaptive evolutionary changes. In a related paper, data were presented on the conus valves and the subendocardium. Here, the structure of the conus myocardium, the subepicardial tissue, and the conus-aorta transition were studied by conventional light, transmission, and scanning electron microscopy. In addition, actin localization by fluorescent phalloidin was used. The conus myocardium is organized into bundles whose spatial organization changes along the conus length. The variable orientation of the myocardial cell bundles may be effective in emptying the conus lumen during contraction and in preventing reflux of blood. Myocardial cell bundles are separated by loose connective tissue that contains collagen and elastin fibers, vessels, and extremely flat cells separating the cell bundles and enclosing blood vessels and collagen fibers. The ultrastructure of the myocardial cells was found to be very similar to that of other fish groups, suggesting that it is largely conservative. The subepicardium is characterized by the presence of nodular structures that contain lympho-hemopoietic (thymus-like) tissue in the young sturgeons and a large number of lymphocytes after the sturgeons reach sexual maturity. This tissue is likely implicated in the establishment and maintenance of the immune responses. The intrapericardial ventral aorta shows a middle layer of circumferentially oriented cells and internal and external layers with cells oriented longitudinally. Elastin fibers completely surround each smooth muscle cell, and the spaces between the different layers are occupied by randomly arranged collagen bundles. The intrapericardial segment of the ventral aorta is a true transitional segment whose structural characteristics are different from those of both the conus subendocardium and the rest of the ventral aorta.  相似文献   
77.
Heterozygous variants in the arginine‐glutamic acid dipeptide repeats gene (RERE) have been shown to cause neurodevelopmental disorder with or without anomalies of the brain, eye, or heart (NEDBEH). Here, we report nine individuals with NEDBEH who carry partial deletions or deleterious sequence variants in RERE. These variants were found to be de novo in all cases in which parental samples were available. An analysis of data from individuals with NEDBEH suggests that point mutations affecting the Atrophin‐1 domain of RERE are associated with an increased risk of structural eye defects, congenital heart defects, renal anomalies, and sensorineural hearing loss when compared with loss‐of‐function variants that are likely to lead to haploinsufficiency. A high percentage of RERE pathogenic variants affect a histidine‐rich region in the Atrophin‐1 domain. We have also identified a recurrent two‐amino‐acid duplication in this region that is associated with the development of a CHARGE syndrome‐like phenotype. We conclude that mutations affecting RERE result in a spectrum of clinical phenotypes. Genotype–phenotype correlations exist and can be used to guide medical decision making. Consideration should also be given to screening for RERE variants in individuals who fulfill diagnostic criteria for CHARGE syndrome but do not carry pathogenic variants in CHD7.  相似文献   
78.
The clavicle has a complex osteologic structure that makes morphological analysis extremely difficult. A three‐dimensional study was conducted to examine the anatomical variations and characteristics of the bone. Sixty‐eight human cadaver clavicles were dissected, CAT‐scanned, and reconstructed. An automated parameterization and correspondence shape analysis system was developed. A new length, designated as centerline (CL) length, was defined and measured. This length represents the true length of the clavicle. The endpoint length was measured as the distance between two endpoints. The width and curvature were measured in the axial (AX) and frontal (FR) plane and defined along the CL. Next gender and side characteristics and variations were examined. The mean CL length was 159.0 ± 11.0 mm. The mean endpoint length was 149.4 ± 10.3 mm, which was statistically significantly shorter than the CL. The male clavicle was significantly longer (166.8 ± 7.3 mm vs. 151.0 ± 8.2 mm), wider (14.6 ± 1.5 mm vs. 12.7 ± 1.3 mm lateral FR plane, 25.9 ± 4.1 mm vs. 23.5 ± 3.0 mm lateral AX plane and 24.7 ± 2.8 mm vs. 22.8 ± 2.8 mm medial AX plane), and more curved (10.8 ± 2.8 mm vs. 8.6 ± 2.3 mm medial and 10.5 ± 3.3 mm vs. 9.1 ± 2.5 mm lateral) than the female one. Left clavicles were significant longer (159.8 ± 10.9 mm vs. 158.0 ± 11.2 mm) than right clavicles. A novel three‐dimensional system was developed, used and tested in order to explore the anatomical variations and characteristics of the human clavicle. This information, together with the automated system, can be applied to future clavicle populations and to the design of fixation plates for clavicle fractures. Clin. Anat. 27:712–723, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
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80.
BackgroundNitric oxide has been proven to play an important role in the maintenance of vascular tone and structure. Impairment of nitric oxide production is an early indicator of atherosclerosis, but not much is known about the real mechanisms underlying this phenomenon.MethodsIn the present study, immunocytochemical methods have been used to analyze the patterns of expression of endothelial nitric oxide synthase and inducible nitric oxide synthase proteins in healthy and atherosclerotic human aortae using both confocal laser scanning microscopy and electron microscopy.ResultsInduction of the expression of endothelial nitric oxide synthase and inducible nitric oxide synthase proteins was observed in smooth muscle cells of atherosclerotic human aortae. Altered nitric oxide synthase expression was reported in atheromatous plaques and in apparently normal vascular tissues adjacent to the lesions.ConclusionsOur data confirm and extend previous findings of a direct relationship between dysregulation of nitric oxide pathway and atherosclerosis, suggesting another possible mechanism by which nitric oxide synthase system abnormalities may promote vascular dysfunction during human atherogenesis. Changes in nitric oxide production might be the primary step in the development of atheroma.  相似文献   
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