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61.
Venous thromboembolism (VTE) has long been considered a disease that affects predominantly white populations, a misconception resulting from a paucity of epidemiological data from non-Western countries, and the low incidence of hereditary thrombophilia in those of non-Caucasian background. Over the last decade, interest has grown in this area with the emergence of evidence that VTE is as prevalent, if not more so, in the black population and is also common in Asian groups. Much is still to be learned, as our current knowledge of hereditary thrombophilia and acquired risk factors do not fully explain the risk of VTE in non-Caucasian groups. This review summarises the current understanding of ethnic variation in VTE and highlights the need for further research in this area. 相似文献
62.
63.
Decreased expression of phospholipase C-beta 2 isozyme in human platelets with impaired function 总被引:4,自引:4,他引:4
Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function. 相似文献
64.
65.
Signal transduction on platelet activation involves phosphoinositide- specific phospholipase C (PLC)-mediated hydrolysis of phosphatidylinositides and formation of inositol-1,4,5-triphosphate [I(1,4,5)P3], which mediates Ca2+ mobilization, and diacylglycerol (DG), which activates protein kinase C (PKC) to phosphorylate a 47-kD protein (Pleckstrin). We studied these events in two related patients previously reported (Blood 74:664, 1989) to have abnormal aggregation and 14C-serotonin secretion, and impaired intracellular Ca2+ mobilization in response to several agonists. Thrombin-induced I(1,4,5)P3 and phosphatidic acid formation were diminished. Pleckstrin phosphorylation was impaired on activation with thrombin, platelet- activating factor, and ionophore A23187, but was normal with PKC activator 1,2-dioctonyl-sn-glycerol (DiC8). Ca2+ mobilization induced by guanosine triphosphate (GTP) analog guanosine 5'-0-(3 thiotriphosphate) (GTP gamma S) was diminished. Pretreatment with either A23187 or DiC8 did not correct the impaired adenine diphosphate- induced secretion; however, upon stimulation with A23187 plus DiC8, pleckstrin phosphorylation and secretion were normal, indicating that both PKC activation and Ca2+ mobilization are essential for normal secretion. We conclude that these patients have a unique inherited platelet defect in formation of two key intracellular mediators [I(1,4,5)P3 and DG] and in the responses mediated by them due to a defect in postreceptor mechanisms of PLC activation. 相似文献
66.
Obesity, one of the most prevalent health problems in the Western world, is a chronic and progressive condition. Therefore, as with other chronic diseases, patients with obesity require lifelong treatment. Long-term efficacy and effectiveness of obesity treatments is notoriously poor. This may in part be attributable to the substantial barriers that undermine long-term obesity management strategies. These can include lack of recognition of obesity as a chronic condition, low socioeconomic status, time constraints, intimate saboteurs, and a wide range of comorbidities including mental health, sleep, chronic pain, musculoskeletal, cardiovascular, respiratory, digestive and endocrine disorders. Furthermore, medications used to treat some of these disorders may further undermine weight-loss efforts. Lack of specific obesity training of health professionals, attitudes and beliefs as well as coverage and availability of obesity treatments can likewise pose important barriers. Health professionals need to take care to identify, acknowledge and address these barriers where possible to increase patient success as well as compliance and adherence with treatments. Failure to do so may further undermine the sense of failure, low self esteem and self efficacy already common among obese individuals. Addressing treatment barriers can save resources and increase the prospect of long-term success. 相似文献
67.
Parisa Aghasi Arya Setoodeh Azadeh Sayarifard Maryam Rashidiyan Fatemeh Sayarifard Ali Rabbani Javad Mahmoudi-Gharaei 《Iranian journal of pediatrics.》2015,25(6)
Background:
Hyperphenylalaninemia (HPA) and Phenylkeonuria (PKU) are metabolic errors caused by deficiency of phenylalanine hydroxylase enzyme, which results in increased level of phenylalanine. This increase is toxic to the growing brain.Objectives:
The purpose of this study was to compare the intellectual and developmental status in HPA and PKU children with normal population in national screening program.Patients and Methods:
In a historical cohort study, 41 PKU patients who had the inclusion criteria and 41 healthy children were evaluated. Wechsler preschool and primary scale of intelligence-3rd edition (WPPI-3) was used in order to assess the intellectual status of children 4 years and older and Ages and stages questionnaire (ASQ) was used to assess the developmental status of children 5 years and younger.Results:
In intellectual test comparison, the two groups showed significant difference in Wechsler’s performance intelligence score and some performance subscales (P-value < 0.01). In comparison of developmental status, no significant difference was observed between the two groups (P-value > 0.05).Conclusions:
Even with early diagnosis and treatment of PKU patients, these children show some deficiencies intellectually compared to normal children. This study emphasizes on necessity for screening intellectual and developmental status of PKU patients so that effective medical or educational measures can taken in case of deficiencies. 相似文献68.
Immunoglobulin V regions and the B cell 总被引:7,自引:2,他引:7
69.
Kumar Umesh Kumar Abhai Singh Smita Arya Payal Singh Sandeep Kumar Chaurasia Rameshwar Nath Singh Anup Kumar Dinesh 《Metabolic brain disease》2021,36(5):957-968
Metabolic Brain Disease - Mild cognitive impairment (MCI) is transition phase between cognitive decline and dementia. The current study aims to investigate altered metabolic pattern in plasma of... 相似文献
70.
Ashish Kumar Jha Gaurav Kumar Vishwa Mohan Dayal Abhay Ranjan Arya Suchismita 《World journal of gastroenterology : WJG》2021,27(18):2090-2104
Hepatitis E virus (HEV) is an important cause of repeated waterborne outbreaks of acute hepatitis. Recently, several extrahepatic manifestations (EHMs) have been described in patients with HEV infection. Of these, neurological disorders are the most common EHM associated with HEV. The involvement of both the peripheral nervous system and central nervous system can occur together or in isolation. Patients can present with normal liver function tests, which can often be misleading for physicians. There is a paucity of data on HEV-related neurological manifestations; and these data are mostly described as case reports and case series. In this review, we analyzed data of 163 reported cases of HEV-related neurological disorders. The mechanisms of pathogenesis, clinico-demographic profile, and outcomes of the HEV-related neurological disorders are described in this article. Nerve root and plexus disorder were found to be the most commonly reported disease, followed by meningoencephalitis. 相似文献