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61.
In the study carried out from, February, 1996 to January, 1999. 42 (33.9%) a typical variants of S typhi which fermented sucrose were encountered. This variant was identified as of antigenic structure 9, 12, v1, d1 and typed as phage type E1 and Bio type I. 相似文献
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Amrita Mandal Hiu-Tung C. Wong Katherine Pinter Natalie Mosqueda Alisha Beirl Richa Madan Lomash Sehoon Won Katie S. Kindt Catherine M. Drerup 《The Journal of neuroscience》2021,41(7):1371
In neurons, mitochondria are transported by molecular motors throughout the cell to form and maintain functional neural connections. These organelles have many critical functions in neurons and are of high interest as their dysfunction is associated with disease. While the mechanics and impact of anterograde mitochondrial movement toward axon terminals are beginning to be understood, the frequency and function of retrograde (cell body directed) mitochondrial transport in neurons are still largely unexplored. While existing evidence indicates that some mitochondria are retrogradely transported for degradation in the cell body, the precise impact of disrupting retrograde transport on the organelles and the axon was unknown. Using long-term, in vivo imaging, we examined mitochondrial motility in zebrafish sensory and motor axons. We show that retrograde transport of mitochondria from axon terminals allows replacement of the axon terminal population within a day. By tracking these organelles, we show that not all mitochondria that leave the axon terminal are degraded; rather, they persist over several days. Disrupting retrograde mitochondrial flux in neurons leads to accumulation of aged organelles in axon terminals and loss of cell body mitochondria. Assays of neural circuit activity demonstrated that disrupting mitochondrial transport and function has no effect on sensory axon terminal activity but does negatively impact motor neuron axons. Taken together, our work supports a previously unappreciated role for retrograde mitochondrial transport in the maintenance of a homeostatic distribution of mitochondria in neurons and illustrates the downstream effects of disrupting this process on sensory and motor circuits.SIGNIFICANCE STATEMENT Disrupted mitochondrial transport has been linked to neurodegenerative disease. Retrograde transport of this organelle has been implicated in turnover of aged organelles through lysosomal degradation in the cell body. Consistent with this, we provide evidence that retrograde mitochondrial transport is important for removing aged organelles from axons; however, we show that these organelles are not solely degraded, rather they persist in neurons for days. Disrupting retrograde mitochondrial transport impacts the homeostatic distribution of mitochondria throughout the neuron and the function of motor, but not sensory, axon synapses. Together, our work shows the conserved reliance on retrograde mitochondrial transport for maintaining a healthy mitochondrial pool in neurons and illustrates the disparate effects of disrupting this process on sensory versus motor circuits. 相似文献
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Pulmonary arteriovenous malformations (PAVM) are abnormal communication of a branch of the pulmonary artery and pulmonary vein circumventing the intervening pulmonary capillaries. This results in a right-to-left (R-L) shunt and its related manifestations, which include hampered gas exchange leading to hypoxaemia, dyspnoea, paradoxical emboli leading to stroke, cerebral abscess, myocardial infarction and pulmonary haemorrhage due to rupture of the PAVM. Endovascular transcatheter embolization of the feeding vessels with coils or occlusion devices is the current standard care of treatment and preferred treatment modality. The articles aim to provide insights into the current trends in diagnosis, the current recommendations, approach and management options for patients with PAVM. 相似文献
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Shivinder Singh Rakhee Goyal G.S. Ramesh V. Ravishankar R.M. Sharma D.V. Bhargava S.K. Singh M.K. John Anoop Sharma 《Medical Journal Armed Forces India》2015,71(1):28-32
Background
The service setting has some unique strengths and weaknesses that must be kept in mind when organizing Hospital acquired infections (HAI) prevention interventions.Methods
Following an initial study to gather data regarding HAI in the Surgical intensive care unit (ICU) we put into place various infection control interventions. The present study was carried out to analyse the effect of these interventions on the incidence of HAI in the ICU.Results
The total admissions to the ICU were 253 patients. Eighty eight patients (34.78%) were admitted for more than 48 hr, 165 patients stayed for less than 48 h. The frequency of HAI was 7.95% (95% CI 3.54, 15). Hospital acquired pneumonia was observed in 2 of the 88 patients (2.27%) (95% CI 0.38, 7.30) which amounted to 9.70 infections per 1000 ventilator days. Bloodstream infection was detected in 3 out of 88 patients (3.4%) (95% CI 0.87, 8.99) amounting to 6.54 fresh infections per 1000 Central Venous Catheter days. Urinary tract infection was observed in 2 (2.27%) (95% CI 0.38, 7.30) at 2.86 fresh infections per 1000 catheter days. As compared to the previous study we found that there was a decline of HAI ranging from 60 to 70%.Conclusion
Our study demonstrated that by meticulously following infection control protocols especially tailored to the service setting the incidence of HAI''s can be reduced. However, the challenge is in maintaining the gains achieved since there is a rapid turnover of manpower in the ICU and a lack of a structured ICU design model. 相似文献69.
V.K. Malhotra Navreet Singh R.S. Bishnoi D.S. Chadha P. Bhardwaj H. Madan R. Dutta A.K. Ghosh S. Sengupta P. Perumal 《Medical Journal Armed Forces India》2015,71(4):324-329
Background
Competitive sports training causes structural and conductive system changes manifesting by various electrocardiographic alterations. We undertook this study to assess the prevalence of abnormal ECG in trained Indian athletes and correlate it with the nature of sports training, that is endurance or strength training.Methods
We evaluated a standard resting, lying 12 lead Electrocardiogram (ECG) in 66 actively training Indian athletes. Standard diagnostic criteria were used to define various morphological ECG abnormalities.Results
33/66 (50%) of the athletes were undertaking endurance training while the other 33 (50%) were involved in a strength-training regimen. Overall 54/66 (81%) sportsmen had significant ECG changes. 68% of these changes were considered as normal training related features, while the remaining 32% were considered abnormal. There were seven common training related ECG changes–Sinus Bradycardia (21%), Sinus Arrhythmia (16%), 1st degree Atrioventricular Heart Block (6%), Type 1 2nd-degree Atrioventicular Heart Block (3%), Incomplete Right bundle branch block (RBBB) (24%), Early Repolarization (42%), Left Ventricular Hypertrophy (LVH) (14%); while three abnormal ECG changes--T-wave inversion (13%), RBBB(4%), Right ventricular hypertrophy (RVH) with strain (29%) were noted. Early repolarization (commonest change), sinus bradycardia, and incomplete RBBB were the commoner features noticed, with a significantly higher presence in the endurance trained athletes.Conclusion
A high proportion of athletes undergoing competitive level sports training are likely to have abnormal ECG recordings. Majority of these are benign, and related to the physiological adaptation to the extreme levels of exertion. These changes are commoner during endurance training (running) than strength training (weightlifting). 相似文献70.
Ajay Madan rew Parkinson Morris D. Faiman 《Alcoholism, clinical and experimental research》1998,22(6):1212-1219
Diethyldithiocarbamate methyl ester (DDTC-Me) is a precursor to the formation of S-methyl-N,N-diethyliolcarbamate sulfoxide, the active metabolite proposed to be responsible for the alcohol deterrent effects of disulfiram. The present study investigated the role of human cytochrome P-450 (CYP) enzymes in sulfoxidation and thiono-oxidation of DDTC-Me, intermediary steps in the activation of disulfiram. Several approaches were used in an attempt to delineate the particular P-450 enzyme(s) involved in the sulfoxidation and thiono-oxidation of DDTC-Me. These approaches included the use of cDNA-expressed human P-450 enzymes, correlation analysis with sample-to-sample variation in human P-450 enzymes in a bank of human liver microsomes, and chemical and antibody inhibition studies. Multiple human P-450 enzymes (CYP3A4, CYPlA2, CYP2A6, and CYP2D6) catalyzed the sulfoxidation of DDTC-Me, as determined with cDNA-expressed enzymes. Several lines of evidence suggest that the sulfoxidation of DDTC-Me by human liver microsomes is primarily catalyzed by CYP3A4/5, including (1) a high correlation between DDTC-Me sulfoxidation and testosterone 6β-hydroxylation; (2) increased DDTC-Me sulfoxidation in the presence of α-naphthoflavone, an activator of CYP3A enzymes; (3) inhibition of this reaction by inhibitors of CYP3A4/5 enzymes, such as troleandomycin and ketoconazole; and (4) inhibition of DDTC-Mesulfoxidation by antibodies against CYP3A enzymes. On the other hand, several lines of evidence suggested that the thiono-oxidation of DDTC-Me by human liver microsomes is catalyzed in part by CYPlA2, CYP266, CYPPEl, and CYP3A4/5, including (1) these human P450 enzymes among others have the capacity to catalyze this reaction, as determined with cDNA-expressed enzymes; (2) a high correlation between DDTC-Me thiono-oxidation and testosterone 6β-hydroxylation, weak inhibition by ketoconazole, troleandomycin, and anti-CYP3A antibodies suggested a minor role for CYP3A4; (3) a high correlation with immunoreactive CYP2B6 suggested involvement of this enzyme; (4) weak inhibition of DDTC-Me thiono-oxidation by furafylline and anti-CYPlA antibody suggested involvement of CYPlA2, and (5) inhibition of DDTC-Me thiono-oxidation by DDTC and anti-CYP2E antibodies suggested a role for CYP2E1. Collectively, these data suggested CYP3A4/5 enzymes are the major contributors to the sulfoxidation of DDTC-Me by human liver microsomes, and CYPlA2, CYP2B6, CYP2E1, and CYP3A4/5 contribute toward DDTC-Me thiono-oxidation by human liver microsomes. This study, in conjunction with others (Madan et al., Drug Metab. Dispos. 23:1153–1162, 1995), may help explain the variability in disulfiram's effectiveness as an alcohol deterrent. 相似文献