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Sidharth Mehan Saloni Rahi Aarti Tiwari Tarun Kapoor Kajal Rajdev Ramit Sharma Himanshi Khera Sourabh Kosey Umesh Kukkar Rajesh Dudi 《中国神经再生研究》2020,(6):1140-1149
Neuronal mitochondrial dysfunction increases inflammatory mediators and leads to free radical generation and anti-oxidant enzymatic alterations,which are major neuropathological hallmarks responsible for autism.Mitochondrial dysfunction in autism is associated with decreased ATP levels due to reduced levels of cyclic adenosine monophosphate.Rat models of autism were established by intracerebroventricular injection of propionic acid.These rat models had memory dysfunction,decreased muscle coordination and gait imbalance.Biochemical estimation of propionic acid-treated rats showed changes in enzyme activity in neuronal mitochondrial electron transport chain complexes and increases in pro-inflammatory cytokines,oxidative stress and lipid biomarkers.Oral administration of 10,20 and 30 mg/kg adenylate cyclase activator forskolin for 15 days reversed these changes in a dose-dependent manner.These findings suggest that forskolin can alleviate neuronal mitochondrial dysfunction and improve neurological symptoms of rats with autism.This study was approved by the RITS/IAEC,SIRSA,HARYANA on March 3,2014(approval No.RITS/IAEC/2014/03/03). 相似文献
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Kevin Y. Zhan MD Sidharth V. Puram MD PhD Michael M. Li MD Dustin A. Silverman MD Amit A. Agrawal MD Enver Ozer MD Matthew O. Old MD Ricardo L. Carrau MD James W. Rocco MD PhD Kevin M. Higgins MD MSc Danny J. Enepekides MD MPH Zain Husain MD Stephen Y. Kang MD Antoine Eskander MD ScM 《Cancer》2020,126(6):1295-1305
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M.D. Li M. Lang F. Deng K. Chang K. Buch S. Rincon W.A. Mehan T.M. Leslie-Mazwi J. Kalpathy-Cramer 《AJNR. American journal of neuroradiology》2021,42(3):429
BACKGROUND AND PURPOSE:The coronavirus disease 2019 (COVID-19) pandemic has led to decreases in neuroimaging volume. Our aim was to quantify the change in acute or subacute ischemic strokes detected on CT or MR imaging during the pandemic using natural language processing of radiology reports.MATERIALS AND METHODS:We retrospectively analyzed 32,555 radiology reports from brain CTs and MRIs from a comprehensive stroke center, performed from March 1 to April 30 each year from 2017 to 2020, involving 20,414 unique patients. To detect acute or subacute ischemic stroke in free-text reports, we trained a random forest natural language processing classifier using 1987 randomly sampled radiology reports with manual annotation. Natural language processing classifier generalizability was evaluated using 1974 imaging reports from an external dataset.RESULTS:The natural language processing classifier achieved a 5-fold cross-validation classification accuracy of 0.97 and an F1 score of 0.74, with a slight underestimation (−5%) of actual numbers of acute or subacute ischemic strokes in cross-validation. Importantly, cross-validation performance stratified by year was similar. Applying the classifier to the complete study cohort, we found an estimated 24% decrease in patients with acute or subacute ischemic strokes reported on CT or MR imaging from March to April 2020 compared with the average from those months in 2017–2019. Among patients with stroke-related order indications, the estimated proportion who underwent neuroimaging with acute or subacute ischemic stroke detection significantly increased from 16% during 2017–2019 to 21% in 2020 (P = .01). The natural language processing classifier performed worse on external data.CONCLUSIONS:Acute or subacute ischemic stroke cases detected by neuroimaging decreased during the COVID-19 pandemic, though a higher proportion of studies ordered for stroke were positive for acute or subacute ischemic strokes. Natural language processing approaches can help automatically track acute or subacute ischemic stroke numbers for epidemiologic studies, though local classifier training is important due to radiologist reporting style differences.There is much concern regarding the impact of the coronavirus disease 2019 (COVID-19) pandemic on the quality of stroke care, including issues with hospital capacity, clinical resource re-allocation, and the safety of patients and clinicians.1,2 Previous reports have shown that there have been substantial decreases in stroke neuroimaging volume during the pandemic.3,4 In addition, acute ischemic infarcts have been found on neuroimaging studies in many hospitalized patients with COVID-19, though the causal relationship is unclear.5,6 Studies like these and other epidemiologic analyses usually rely on the creation of manually curated databases, in which identification of cases can be time-consuming and difficult to update in real-time. One way to facilitate such research is to use natural language processing (NLP), which has shown utility for automated analysis of radiology report data.7 NLP algorithms have been developed previously for the classification of neuroradiology reports for the presence of ischemic stroke findings and acute ischemic stroke subtypes.8,9 Thus, NLP has the potential to facilitate COVID-19 research.In this study, we developed an NLP machine learning model that classifies radiology reports for the presence or absence of acute or subacute ischemic stroke (ASIS), as opposed to chronic stroke. We used this model to quantify the change in ASIS detected on all CT or MR imaging studies performed at a large comprehensive stroke center during the COVID-19 pandemic in the United States. We also evaluated NLP model generalizability and different training strategies using a sample of radiology reports from a second stroke center. 相似文献
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Sidharth Sonthalia M.D. D.N.B. Archana Singal M.D. M.N.A.M.S. 《Pediatric dermatology》2016,33(3):e186-e189
Deposition of smegma in the subpreputial region is common in young uncircumcised boys. Although the term “smegma pearls” has been used colloquially for this entity, there is an apparent lack of reference to smegma pearls and their characteristics in the extant scientific literature. We present a series of six Indian boys with smegma pearls and discuss their possible origin, course, and management. 相似文献
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It is common for primary care physicians to be faced with children with hematological disorders in everyday practice. The article seeks to provide realistic information for the first-contact physician in handling common hematological diseases in children. Practical step-wise approach to understanding and investigating anemia and bleeding disorders is illustrated. Requirement of iron in normal children and management of iron deficiency anemia (IDA) and thalassemia is explained. The gold standard for IDA continues to be ferrous sulphate which has good bioavailability and is inexpensive. There is emerging concept of delayed clamping of umbilical cord at birth, particularly in regions with widespread IDA, to augment iron stores in infancy. Typical case scenarios of children with immune thrombocytopenia (ITP) and hemophilia are provided to facilitate the understanding of management in day to day practice. The vital role of the medical practitioner in shared care of patients with acute lymphoblastic leukemia and febrile neutropenia is emphasized. A risk based treatment algorithm for febrile neutropenia is provided. 相似文献
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