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991.
Hypertrophic cardiomyopathy (HCM) is a complex and common genetic disease. The left ventricular outflow tract obstruction is an important determinant of symptoms and outcomes. Its pathophysiology is determined by the complex interaction of the mitral valve, papillary muscles, chordae tendinea, and interventricular septum. The knowledge and importance of the mitral valve apparatus in the physiology of the HCM are expanding with the new imaging modalities, in particular, cardiac magnetic resonance. Several abnormalities of the mitral apparatus have been described in patients with HCM including abnormal papillary muscles, leaflets' lengths, and mitral regurgitation. Ignoring these variables can lead to unnecessary or incomplete surgical treatments and worse outcomes. This review discusses the role of the mitral apparatus in HCM with a focus on a multimodality imaging approach and the clinical importance of each abnormality. 相似文献
992.
Cuervo R Hernández-Martínez R Chimal-Monroy J Merchant-Larios H Covarrubias L 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(10):3838-3843
Full limb regeneration is a property that seems to be restricted to urodele amphibians. Here we found that Polypterus, the most basal living ray-finned fish, regenerates its pectoral lobed fins with a remarkable accuracy. Pectoral Polypterus fins are complex, formed by a well-organized endoskeleton to which the exoskeleton rays are connected. Regeneration initiates with the formation of a blastema similar to that observed in regenerating amphibian limbs. Retinoic acid induces dose-dependent phenotypes ranging from inhibition of regeneration to apparent anterior-posterior duplications. As in all developing tetrapod limbs and regenerating amphibian blastema, Sonic hedgehog is expressed in the posterior mesenchyme during fin regeneration. Hedgehog signaling plays a role in the regeneration and patterning processes: an increase or reduction of fin bony elements results when this signaling is activated or disrupted, respectively. The tail fin also regenerates but, in contrast with pectoral fins, regeneration can resume after release from the arrest caused by hedgehog inhibition. A comparative analysis of fin phenotypes obtained after retinoic acid treatment or altering the hedgehog signaling levels during regeneration allowed us to assign a limb tetrapod equivalent segment to Polypterus fin skeletal structures, thus providing clues to the origin of the autopod. We propose that appendage regeneration was a common property of vertebrates during the fin to limb transition. 相似文献
993.
MA Lima A Aversa P Maranhão-Filho GA Lima A Curi CA Schmaltz FM Santanna 《Revista do Instituto de Medicina Tropical de S?o Paulo》2012,54(4):229-230
Brain tuberculomas account for 10-20% of space occupying brain lesions in developing countries. Most lesions are observed at time of tuberculosis diagnosis or soon after starting treatment. We herein describe a 32 year-old patient with a 14-month history of headache and progressive visual loss. Her past medical history revealed pulmonary tuberculosis treated eight years before. A brain MRI showed a T1- and T2-weighted isointense contrast-enhancing lesion in the optic chiasm. A presumptive diagnosis of optochiasmatic tuberculoma was made and isoniazid, rifampin, pyrazinamide, and ethambutol were started. Despite treatment, the patient evolved to blindness. The prompt recognition of this condition is extremely important since the presence of optochiasmal enhancement is associated with blindness in patients with tuberculosis. 相似文献
994.
995.
Recent advances in Schistosoma genomics 总被引:1,自引:0,他引:1
Schistosome research has entered the genomic era with the publications reporting the Schistosoma mansoni and Schistosoma japonicum genomes. Schistosome genomics is motivated by the need for new control tools. However, much can also be learned about the biology of Schistosoma, which is a tractable experimental model. In this article, we review the recent achievements in the field of schistosome research and discuss future perspectives on genomics and how it can be integrated in a usable format, on the genetic mapping and how it has improved the genome assembly and provided new research approaches, on how epigenetics provides interesting insights into the biology of the species and on new functional genomics tools that will contribute to the understanding of the function of genes, many of which are parasite- or taxon specific. 相似文献
996.
Burti JS Santos AM Pereira RM Zambon JP Marques AP 《Archives of gerontology and geriatrics》2012,54(2):e42-e46
To estimate the prevalence of urinary incontinence (UI) in elderly individuals of low income assisted by the primary health care system in S?o Paulo, Brazil. In this community-based, observational, cross-sectional study, participants assisted by the health family program in S?o Paulo, Brazil, were sampled and interviewed face to face by questionnaire. Participants (n=388) were selected from the collaborative program developed by the 10/66 Dementia Research Group, an International Network of investigators. Demographics, health history and a detailed assessment of UI and urinary symptoms were obtained. Prevalence of UI was calculated. Other variables included age, body mass index (BMI), duration of incontinence and characteristics of the symptoms. The association between UI and the variables was estimated using the Kruskal-Wallis test, Chi-squared test and Fisher test (depending on normality of the distribution and expected frequencies). Prevalence of UI was 38.4%. UI was more common in women than in men (50% vs. 18.3%, p<0.001). Diabetes, obesity and hypertension were associated with UI. Almost 36.2% of the cases were of mixed incontinence, 26.8% of urge incontinence and 24.2% of stress incontinence. Men were more likely to have urge-incontinence, while women were more likely to have mixed incontinence (p=0.001). UI is prevalent in the elderly of low income living in S?o Paulo and rates are higher than most previous studies. Chronic conditions such as hypertension, diabetes and obesity were associated with UI. 相似文献
997.
Kuyumcu ME Yesil Y Oztürk ZA Cınar E Kızılarslanoglu C Halil M Ulger Z Yesil NK Cankurtaran M Arıoğul S 《Archives of gerontology and geriatrics》2012,55(3):739-743
Previous studies showed oxidative stress had an important impact on osteoclastic and osteoblastic functions. Oxidative stress or low levels of antioxidants are supposed to reduce BMD and cause osteoporosis. hcy, gamma glutamyltransferase (GGT), uric acid, albumin and total bilirubin are simple laboratory parameters that are related with oxidative stress. In this study we compare the serum hcy and antioxidant levels in patients with osteoporosis, osteopenia and control subjects. A total of 2190 elderly persons (1348 patients with osteoporosis, 643 patients with osteopenia and 199 control subjects) who were referred to the outpatient clinic of the Department of Internal Medicine, Division of Geriatric Medicine at Hacettepe University Hospital for comprehensive geriatric assessment were included in this cross-sectional study. Mean age of subjects were 72.30±6.34 in osteoporosis group, 71.92±6.90 in osteopenia and 71.86±5.88 in control group (p: 0.260). Multivariate regression analysis revealed that hypertension (HT) (OR: 0.675, 95% CI: 0.534-0.854, p: 0.001), diabetes mellitus (DM) (OR: 1.669, 95% CI: 1.301-2.142, p: <0.001), age (OR: 1.025, 95% CI: 1.006-1.044, p: 0.009), male gender (OR: 0.451, 95% CI: 0.358-0.569, p<0.001), uric acid (OR: 0.893, 95% CI: 0.837-0.952, p: 0.001), hcy (OR: 1.042, 95% CI: 1.023-1.061, p<0.001), albumin (OR: 0.521, 95% CI: 0.376-0.724, p<0.001), GGT (OR: 1.010, 95% CI: 1.003-1.017, p: 0.003), creatinine (OR: 0.630, 95% CI: 0.459-0.864, p: 0.004) were independent variables predicting the occurrence of osteoporosis. This study shows there is an imbalance between natural antioxidative and oxidative markers in patients with osteoporosis. Higher serum uric acid and albumin levels are associated with a lower prevalence of osteoporosis whereas higher hcy and GGT levels are associated lower BMD and higher osteoporosis prevalence. 相似文献
998.
Tomé-Carneiro J Gonzálvez M Larrosa M Yáñez-Gascón MJ García-Almagro FJ Ruiz-Ros JA García-Conesa MT Tomás-Barberán FA Espín JC 《The American journal of cardiology》2012,110(3):356-363
The search for complementary treatments in primary prevention of cardiovascular disease (CVD) is a high-priority challenge. Grape and wine polyphenol resveratrol confers CV benefits, in part by exerting anti-inflammatory effects. However, the evidence in human long-term clinical trials has yet to be established. We aimed to investigate the effects of a dietary resveratrol-rich grape supplement on the inflammatory and fibrinolytic status of subjects at high risk of CVD and treated according to current guidelines for primary prevention of CVD. Seventy-five patients undergoing primary prevention of CVD participated in this triple-blinded, randomized, parallel, dose-response, placebo-controlled, 1-year follow-up trial. Patients, allocated in 3 groups, consumed placebo (maltodextrin), a resveratrol-rich grape supplement (resveratrol 8 mg), or a conventional grape supplement lacking resveratrol, for the first 6 months and a double dose for the next 6 months. In contrast to placebo and conventional grape supplement, the resveratrol-rich grape supplement significantly decreased high-sensitivity C-reactive protein (-26%, p = 0.03), tumor necrosis factor-α (-19.8%, p = 0.01), plasminogen activator inhibitor type 1 (-16.8%, p = 0.03), and interleukin-6/interleukin-10 ratio (-24%, p = 0.04) and increased anti-inflammatory interleukin-10 (19.8%, p = 0.00). Adiponectin (6.5%, p = 0.07) and soluble intercellular adhesion molecule-1 (-5.7%, p = 0.06) tended to increase and decrease, respectively. No adverse effects were observed in any patient. In conclusion, 1-year consumption of a resveratrol-rich grape supplement improved the inflammatory and fibrinolytic status in patients who were on statins for primary prevention of CVD and at high CVD risk (i.e., with diabetes or hypercholesterolemia plus ≥1 other CV risk factor). Our results show for the first time that a dietary intervention with grape resveratrol could complement the gold standard therapy in the primary prevention of CVD. 相似文献
999.
There is an evidence of abnormal metabolism in the vitamin D endocrine system of patients with leprosy. Bone deformities usually occur in patients with leprosy. Genetic factors, such as the vitamin D receptor, the major histocompatibility complex region, chromosome 20, human toll-like receptors, the natural resistance-associated macrophage protein 1, the nucleotide-binding oligomerization domain containing 2, phosphate-regulating gene with homologies to endopeptidase on the X chromosome and the tyrosine kinase growth factor receptor-ErbB-2, contribute to both vitamin D status and leprosy. The role of vitamin D in leprosy has been demonstrated by its effects on Bacillus Calmette-Guérin vaccination, vascular endothelial growth factor, prostaglandins, reactive oxygen species, reactive nitrogen intermediates, matrix metalloproteinases, antiphospholipid syndrome and the nerve growth factor. Vitamin D plays a definite role in leprosy. Vitamin D, itself, may effect on leprosy through the vitamin D receptors or may influence leprosy through indirect effects. 相似文献
1000.
Weiler FG Dias-da-Silva MR Lazaretti-Castro M 《Arquivos brasileiros de endocrinologia e metabologia》2012,56(1):54-66
Autoimmune polyendocrine syndrome type 1 (APECED) is a rare autosomal recessive disorder characterized by autoimmune multiorgan attack. The disease is caused by mutations in the autoimmune regulator gene (AIRE), resulting in defective AIRE protein, which is essential for selftolerance. Clinical manifestations are widely variable. Although the classic triad is composed by mucocutaneous candidiasis, hypoparathyroidism and adrenal failure, many other components may develop. Treatment is based on supplementation of the various deficiencies, and patients require regular follow-up throughout their lifespan. This article describes the case of a patient with the disease, and reviews literature data on the epidemiology, clinical course, immunogenetic aspects, diagnosis and treatment of the syndrome. 相似文献