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ObjectiveThe prognostic value of MAC severity is important not only because it shares a common risk factors with vascular atherosclerotic changes but also through increasing the cardiovascular morbidity and mortality. This study was conducted in order to evaluate association between severity of MAC and left sided echocardiographic abnormalities mainly left sided valvular abnormalities as well as left atrial systolic and diastolic functional abnormalities.MethodsWe prospectively obtained 12-leads electrocardiograms and transthoracic echocardiograms (TTE) on patients scheduled for non-emergent echocardiographic assessment at tertiary care hospital. MAC was graded as mild, moderate and severe. LA linear dimensions, LA filling and emptying volumes and left atrium ejection fraction were done specifically in addition to commonly measured TTE parameters.ResultsFrom the 80 patients considered for the study, 47 patients had mild MAC, 29 patients had moderate MAC and 4 patients had severe MAC. Valvular affection through echo-doppler assessment that included mainly mitral stenosis, mitral incompetence, aortic sclerosis as well as aortic incompetence showed a highly significant statistical difference (p-values 0.00, 0.00, 0.00 and 0.00 respectively). There was a highly significant statistical difference between patients with different degrees of MAC and LA linear dimension (p-value 0.00), all LA filling and emptying volumes as well as LA ejection fractions with the exception of LA passive emptying volume and LA passive ejection fraction was insignificant.ConclusionsThere is a direct proportionate relationship between severity of MAC and associated left sided valvular affection, increase LA linear dimension as well as lower overall LA function. 相似文献
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Hany Goubran Botros Pierre Legrand Cecile Pagan Vincent Bondet Patrick Weber Mariem Ben‐Abdallah Nathalie Lemière Guillaume Huguet Jacques Bellalou Erik Maronde Pierre Beguin Ahmed Haouz William Shepard Thomas Bourgeron 《Journal of pineal research》2013,54(1):46-57
Abstract: Melatonin is a synchronizer of many physiological processes. Abnormal melatonin signaling is associated with human disorders related to sleep, metabolism, and neurodevelopment. Here, we present the X‐ray crystal structure of human N‐acetyl serotonin methyltransferase (ASMT), the last enzyme of the melatonin biosynthesis pathway. The polypeptide chain of ASMT consists of a C‐terminal domain, which is typical of other SAM‐dependent O‐methyltransferases, and an N‐terminal domain, which intertwines several helices with another monomer to form the physiologically active dimer. Using radioenzymology, we analyzed 20 nonsynonymous variants identified through the 1000 genomes project and in patients with neuropsychiatric disorders. We found that the majority of these mutations reduced or abolished ASMT activity including one relatively frequent polymorphism in the Han Chinese population (N17K, rs17149149). Overall, we estimate that the allelic frequency of ASMT deleterious mutations ranges from 0.66% in Europe to 2.97% in Asia. Mapping of the variants on to the 3‐dimensional structure clarifies why some are harmful and provides a structural basis for understanding melatonin deficiency in humans. 相似文献
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ABSTRACT: BACKGROUND: In childhood, attention deficit/hyperactivity disorder (ADHD) is characterized by age-inappropriate levels of inattentiveness/disorganization, hyperactivity/impulsiveness, or a combination thereof. Although the criteria for ADHD are well defined, the long-term consequences in adults and children need to be more comprehensively understood and quantified. We conducted a systematic review evaluating the long-term outcomes (defined as 2 years or more) of ADHD with the goal of identifying long-term outcomes and the impact that any treatment (pharmacological, non-pharmacological, or multimodal) has on ADHD long-term outcomes. METHODS: Studies were identified using predefined search criteria and 12 databases. Studies included were peer-reviewed, primary studies of ADHD longterm outcomes published between January 1980 to December 2010. Inclusion was agreed on by two independent researchers on review of abstracts or full text. Published statistical comparison of outcome results were summarized as poorer than, similar to, or improved versus comparators, and quantified as percentage comparisons of these categories. RESULTS: Outcomes from 351 studies were grouped into 9 major categories: academic, antisocial behavior, driving, non-medicinal drug use/addictive behavior, obesity, occupation, services use, self-esteem, and social function outcomes. The following broad trends emerged: (1) without treatment, people with ADHD had poorer long-term outcomes in all categories compared with people without ADHD, and (2) treatment for ADHD improved long-term outcomes compared with untreated ADHD, although not usually to normal levels. Only English-language papers were searched and databases may have omitted relevant studies. CONCLUSIONS: This systematic review provides a synthesis of studies of ADHD long-term outcomes. Current treatments may reduce the negative impact that untreated ADHD has on life functioning, but does not usually 'normalize' the recipients. 相似文献
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Varinder Kaur Arjun Swami Daisy Alapat Al Ola Abdallah Pooja Motwani Laura F. Hutchins 《Hematology (Amsterdam, Netherlands)》2018,23(1):17-24
Background: Myeloid sarcoma (MS) is characterized by extramedullary infiltration by immature myeloid cells. Owing to rarity of this disease, the clinical features and overall outcomes are yet to be clarified.Objective: To define clinical characteristics, epidemiology, pathologic findings, treatment options and outcomes in MS.Methods: We conducted a retrospective review of 23 patients diagnosed with MS at our institute over a period of 13 years (2002–2015).Results: MS presented mostly as a manifestation of relapsed acute myeloid leukemia, seen in 39% of patients. Skin and subcutaneous soft tissues were the most common sites of anatomic involvement (69.5%). Ninety five percent (n?=?19) were positive for classical myeloid markers with either cytochemical staining (chloracetate-esterase, MPO), flow-cytometry (CD33, CD34, CD13 and CD117), or immunohistochemistry (CD34, CD43, CD68 and lysozyme). Of these, 52% were positive for CD33 (n?=?12), 35% for CD68 (n?=?8), 30% for CD34 (n?=?7), and 26% for lysozyme (n?=?6). Cytogenetic abnormalities were seen in 63% (n?=?12/19) patients on bone-marrow aspirate, with five patients displaying a complex (n?=?3) or monosomal (n?=?2) karyotype. Twenty seven percent patients with a normal karyotype had presence of deleterious mutations (FLT3, ASXL, STAG and JAK2) on further testing with myeloid mutation panel. The Median overall survival (OS) of the entire cohort was 15.9 months (95% CI, 7.4–24.4 months). The OS was significantly better for patients <65 years (24.6 vs. 3.4 months, p?=?0.009) of age, and for those attaining a complete remission (CR) to induction therapy (25.7 vs. 0.8 months, p?0.001). All patients who underwent allogeneic hematopoietic stem cell transplant attained long-term remissions, with a median follow-up of 54 (range 32–120) months.Conclusion: Failure to achieve CR with induction therapy, and age >65 years are associated with poor outcomes in MS. Allogeneic stem-cell transplant in first remission appears to be the most effective modality for achieving long-term remissions. 相似文献