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41.
Hypertrophic cardiomyopathy (HCM) is a genetic cardiomyopathy. The prevalence of phenotypic expression, in the absence of another systemic or cardiac disease causing increased left ventricular (LV) wall thickness, is estimated to be 1:500. The frequency of clinical presentation is far less, highlighting the need for a non-invasive diagnostic imaging tool. Echocardiography is readily available and allows for structural characterization and hemodynamic assessment of the hypertrophic heart and to screen patients at-risk for HCM, such as first degree relatives of affected individuals, and differentiate HCM from the athletic heart. Echocardiography can also be used to assess for anatomic abnormalities of the mitral valve apparatus that may exacerbate LV outflow track obstruction and to further risk stratify patients during exercise. Finally, echocardiography plays an integral role in guiding alcohol septal ablation procedures. 相似文献
42.
Goel PK Srivastava SK Ashfaq F Gupta PR Saxena PC Agarwal R Kumar S Garg N Tewari S Kapoor A 《Indian heart journal》2012,64(3):295-301
To assess the medico social demographics of acute myocardial infarction (AMI) in our community we studied 609 patients presenting between January 2008 to December 2008 with a detailed questionnaire in four centres of UP. Medical attention was sought late (> 6 hours) in 316 (51.6%), thrombolysis was obtained in 45.2% (275) and presentation was atypical in 16.3% (99). 36.2% (221) had pre-monitory symptoms of which 68% (150) ignored the same while of 32% (71) who did seek medical attention 47.9% (37) were brushed away as non-cardiac in origin. 20.3% (46/226) of hypertension, 23.2% (43/185) of diabetes and 83.4% (91/109) of hyperlipidaemia was diagnosed post event. We conclude that at least half of patients with AMI do not get definitive therapy, at least one in 10 patients do not have the classical symptoms, reasonable proportion are unaware of their risk factors, and a good majority have pre-monitory symptoms which get overlooked. 相似文献
43.
Smith P Wang LK Nair PA Shuman S 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(7):2296-2301
Pnkp is the end-healing and end-sealing component of an RNA repair system present in diverse bacteria from ten different phyla. To gain insight to the mechanism and evolution of this repair system, we determined the crystal structures of the ligase domain of Clostridium thermocellum Pnkp in three functional states along the reaction pathway: apoenzyme, ligase•ATP substrate complex, and covalent ligase-AMP intermediate. The tertiary structure is composed of a classical ligase nucleotidyltransferase module that is embellished by a unique α-helical insert module and a unique C-terminal α-helical module. Structure-guided mutational analysis identified active site residues essential for ligase adenylylation. Pnkp defines a new RNA ligase family with signature structural and functional properties. 相似文献
44.
Ravishankar B Liu H Shinde R Chandler P Baban B Tanaka M Munn DH Mellor AL Karlsson MC McGaha TL 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(10):3909-3914
Tolerance to self-antigens present in apoptotic cells is critical to maintain immune-homeostasis and prevent systemic autoimmunity. However, mechanisms that sustain self-tolerance are poorly understood. Here we show that systemic administration of apoptotic cells to mice induced splenic expression of the tryptophan catabolizing enzyme indoleamine 2,3-dioxygenase (IDO). IDO expression was confined to the splenic marginal zone and was abrogated by depletion of CD169(+) cells. Pharmacologic inhibition of IDO skewed the immune response to apoptotic cells, resulting in increased proinflammatory cytokine production and increased effector T-cell responses toward apoptotic cell-associated antigens. Presymptomatic lupus-prone MRL(lpr/lpr) mice exhibited abnormal elevated IDO expression in the marginal zone and red pulp and inhibition of IDO markedly accelerated disease progression. Moreover, chronic exposure of IDO-deficient mice to apoptotic cells induced a lupus-like disease with serum autoreactivity to double-stranded DNA associated with renal pathology and increased mortality. Thus, IDO limits innate and adaptive immunity to apoptotic self-antigens and IDO-mediated regulation inhibits inflammatory pathology caused by systemic autoimmune disease. 相似文献
45.
Pravin K. Goel Aditya Kapoor Aditya Batra Roopali Khanna 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2012,39(5):653-656
In selected patients, transcatheter closure of atrial septal defects with the AMPLATZER Septal Occluder has yielded excellent results. However, there is a slight risk of device embolization after deployment. We report the case of a 26-year-old woman in whom an embolized AMPLATZER device was retrieved percutaneously from the right pulmonary artery. We also discuss important technical principles for managing this uncommon but potentially severe complication.Key words: Device removal/methods, embolization, therapeutic/instrumentation, heart catheterization/instrumentation, heart septal defects, atrial/ultrasonography, patient selection, prosthesis implantation/adverse effects, prostheses and implants, septal occluder device/adverse effects, treatment outcomeTranscatheter closure of atrial septal defects (ASDs) with use of the AMPLATZER® Septal Occluder (St. Jude Medical, Inc.; St. Paul, Minn) has yielded excellent results in properly selected patients.1,2 The major advantage of the AMPLATZER occluder is its easy retrieval at all stages of deployment before its final release from the delivery cable. Although embolization of AMPLATZER ASD occluders is rare, it can occur even when interventional cardiologists are experienced. Despite an earlier belief that the transcatheter retrieval of embolized AMPLATZER devices would be difficult, success rates from 50% to 75% have been reported.3,4 We describe the retrieval of an embolized AMPLATZER device in a young woman. In addition, we present some technical principles with which operators practicing device closure should be familiar. 相似文献
46.
Vivek Pravin Dave Mudit Tyagi Raja Narayanan Rajeev Reddy Pappuru 《Indian journal of ophthalmology》2021,69(1):14
Optimal visualization is one of the most challenging aspects of performing vitreoretinal surgery. In situations where conventional microscopic techniques provide poor posterior visualization, the adjunctive skill set of endoscopic visualization may be needed. This allows for by-passing the opaque anterior segment media and getting access to the posterior segment pathology. Endoscopic vitrectomy is a useful and unique adjunct to microincision vitreoretinal surgery. The optical set-up of endoscopy allows for clinical approaches that are impossible with regular microscope viewing systems. These include the ability to observe across optically significant anterior segment opacities and directly visualize the posterior segment of the eye. It also allows for visualizing the difficult-to-access retroirideal, retrolental, and anterior retinal structures. Surgical access to anatomic spaces like the pars plana, pars plicata, ciliary sulcus, ciliary body, and peripheral lens is tedious. This is made simpler by endoscopy. In this review, we summarize and review the usage of the intraocular endoscope as a diagnostic and therapeutic armamentarium across a wide spectrum of ocular pathologies. 相似文献
47.
48.
Shivalika Sehgal Lakshmi Shinde Gopinath Madheswaran Paula Mukherjee Pavan Verkicharla Soumya Easwaran Kalika Bandamwar 《Indian journal of ophthalmology》2021,69(4):958
Purpose:The optometry profession has experienced massive changes amid lockdown in COVID 19 pandemic. This study gauges the impact of COVID-19 on optometry education and practices in India.Methods:The impact of COVID-19 among key stakeholders of Indian optometry that included educators, students, and practitioners was surveyed. The content validity of the survey tool was achieved through a focused group discussion with experts.Results:Of the 1408 responses, 118 were educators, 845 were students and 445 were practitioners. Post COVID-19 lock-down, a high percentage of students (96%) and educators (94%) were now using online mode of education to learn and teach. The blended learning methods were reported to be used by 81% of educators. Practical skills were the most difficult to teach by educators and to learn by students. Almost a third of the students were concerned about their internships and job opportunities amid the pandemic. Practitioners felt confident in performing routine eye examinations with personal protective equipment (PPE). Telemedicine was found to be adopted by 55% of the private practitioners and 49% of the eye hospitals.Conclusion:The COVID-19 pandemic has provided an opportunity to reform Indian optometry education through blended learning methods. Optometry practices changed and adapted instantly to the new hygiene norms that have raised the standard of care provided to patients. Telemedicine emerged as a mode of providing care by optometrists. Overall, all key stakeholders of optometry in India were found to have adapted well to the sudden changes due to COVID 19 pandemic. 相似文献
49.
50.
Background contextComputed tomography (CT) has become the sole modality of screening for cervical injury in polytrauma because of the high sensitivity, speed, and convenience, thereby eliminating the need for plain radiographs.PurposeWe report two cases of misleading artifactual fracture-subluxation of cervical spine in CT, which could have resulted in needless treatment, and describe its characteristics.Study designCase report and review.MethodsTwo patients who were initially diagnosed with fracture-subluxation on screening CT cervical spine were later noted to have motion artifacts and were reviewed.ResultsThe artifactual nature of the supposed fracture-subluxation was unmasked by the soft-tissue findings of obscuration in sagittal reconstruction and duplication in axial images, along with the presence of double bony margins.ConclusionsMotion artifact in cervical CT screening can lead to a misdiagnosis of fracture subluxation. Duplication of soft tissue is highly suggestive of this motion artifact, and an additional single lateral plain radiograph may avert this pitfall. 相似文献