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21.
Santosh Gopi Krishna Gadde Akhila Sridharan Nikitha Reddy Gurram B Poornachandra Nivedhitha Govindasamy Chaitra Jayadev 《Indian journal of ophthalmology》2022,70(2):465
Purpose:To compare multicolor imaging (MCI) with Optos color fundus photography (OCFP) for the evaluation of morphology and extent of preretinal membranes in diabetic tractional retinal detachments (TRD).Methods:In this retrospective study, 30 eyes with diabetic TRDs were imaged using the MCI feature of the Heidelberg Spectralis Spectral-domain optical coherence tomography (SD-OCT) and color photo using the Optos Daytona ultra-widefield fundus camera. Two investigators independently graded and determined the agreeability between the two modalities with respect to the extent of the TRD and preretinal membranes on the SD-OCT B-scan images.Results:The MCI provided better visualization of the attachments and traction points of the posterior hyaloid face and preretinal membranes and is comparable to the SD-OCT B-scan images. The inter-rater agreeability rates for OCFP had a Kappa (κ) value of 0.37, while the MCI had a κ value of 0.46. When comparing between images of different wavelengths, grading using infrared reflectance (IR) had a poor agreement (−0.04 ± 0.04) while green reflectance (GR) (0.46 ± 0.32) and blue reflectance (BR) (0.53 ± 0.19) had a moderate agreement. The composite MCI and GR images also had comparatively higher intraclass coefficient when compared to the OCFP (0.25 [−0.09–0.55]) and IR (−0.03 [−0.39–0.34]) images.Conclusion:MCI is more sensitive for determining the extent of TRDs and for the detection of secondary membranes when compared to OCFP, thus, aiding in better surgical planning. 相似文献
22.
Kavalipurapu Venkata Teja Sindhu Ramesh Gopi Battineni Kaligotla Apoorva Vasundhara Jerry Jose Krishnamachari Janani 《Saudi Dental Journal》2022,34(2):87-99
BackgroundFluid dynamics is a majorly neglected aspect to be studied in root canal irrigation. The fundamental rule to understand mechanics is to observe patterns of flow during the process. Thus, this work is conducted to do a systemic assessment of the in-vitro and ex-vivo based studies to evaluate the effect of various parameters on the irrigant flow and apical pressure on using a manual syringe needle for root canal irrigation.MethodsThe literature search was conducted through libraries such as PubMed (Medline), CINAHL, Embase, Scopus and other hand literature from Google Scholar, the British medical library etc. The systematic review was reported following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. As they include studies that were in-vitro and ex-vivo based, the risk of bias of the selected articles was assessed using a customized tool based on the previous literature and parameters evaluated in the studies included.ResultsThe literature search resulted in 101 items of which 19 records were included in this review. Results reported that multiple factors and parameters were assessed to evaluate the flow and apical pressures on using manual syringe needle irrigation.ConclusionsPresent systematic review gives insights in-depth about the irrigation dynamics of manual syringe needle irrigation. Besides, it is inconclusive to compile a single factor or a single parameter contributing to the enhanced irrigant flow and least apical pressures. 相似文献
23.
Shyamal C. Bir Christopher B. Pattillo Sibile Pardue Gopi K. Kolluru Xinggui Shen Tony Giordano Christopher G. Kevil 《Diabetes》2014,63(1):270-281
Nitrite anion has been demonstrated to be a prodrug of nitric oxide (NO) with positive effects on tissue ischemia/reperfusion injury, cytoprotection, and vasodilation. However, effects of nitrite anion therapy for ischemic tissue vascular remodeling during diabetes remain unknown. We examined whether sodium nitrite therapy altered ischemic revascularization in BKS-Leprdb/db mice subjected to permanent unilateral femoral artery ligation. Sodium nitrite therapy completely restored ischemic hind limb blood flow compared with nitrate or PBS therapy. Importantly, delayed nitrite therapy 5 days after ischemia restored ischemic limb blood flow in aged diabetic mice. Restoration of blood flow was associated with increases in ischemic tissue angiogenesis activity and cell proliferation. Moreover, nitrite but not nitrate therapy significantly prevented ischemia-mediated tissue necrosis in aged mice. Nitrite therapy significantly increased ischemic tissue vascular endothelial growth factor (VEGF) protein expression that was essential for nitrite-mediated reperfusion of ischemic hind limbs. Nitrite significantly increased ischemic tissue NO bioavailability along with concomitant reduction of superoxide formation. Lastly, nitrite treatment also significantly stimulated hypoxic endothelial cell proliferation and migration in the presence of high glucose in an NO/VEGF-dependent manner. These results demonstrate that nitrite therapy effectively stimulates ischemic tissue vascular remodeling in the setting of metabolic dysfunction that may be clinically useful. 相似文献
24.
Angela Keniston Matthew Sakumoto Gopi J. Astik Andrew Auerbach Shaker M. Eid Kirsten N. Kangelaris Shradha A. Kulkarni Tiffany Lee Luci K. Leykum Anne S. Linker Devin T. Worster Marisha Burden 《Journal of general internal medicine》2022,37(15):3956
BackgroundDuring the initial wave of COVID-19 hospitalizations, care delivery and workforce adaptations were rapidly implemented. In response to subsequent surges of patients, institutions have deployed, modified, and/or discontinued their workforce plans.ObjectiveUsing rapid qualitative methods, we sought to explore hospitalists’ experiences with workforce deployment, types of clinicians deployed, and challenges encountered with subsequent iterations of surge planning during the COVID-19 pandemic across a collaborative of hospital medicine groups.ApproachUsing rapid qualitative methods, focus groups were conducted in partnership with the Hospital Medicine Reengineering Network (HOMERuN). We interviewed physicians, advanced practice providers (APP), and physician researchers about (1) ongoing adaptations to the workforce as a result of the COVID-19 pandemic, (2) current struggles with workforce planning, and (3) evolution of workforce planning.Key ResultsWe conducted five focus groups with 33 individuals from 24 institutions, representing 52% of HOMERuN sites. A variety of adaptations was described by participants, some common across institutions and others specific to the institution’s location and context. Adaptations implemented shifted from the first waves of COVID patients to subsequent waves. Three global themes also emerged: (1) adaptability and comfort with dynamic change, (2) the importance of the unique hospitalist skillset for effective surge planning and redeployment, and (3) the lack of universal solutions.ConclusionsHospital workforce adaptations to the COVID pandemic continued to evolve. While few approaches were universally effective in managing surges of patients, and successful adaptations were highly context dependent, the ability to navigate a complex system, adaptability, and comfort in a chaotic, dynamic environment were themes considered most critical to successful surge management. However, resource constraints and sustained high workload levels raised issues of burnout.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-022-07480-x.KEY WORDS: COVID-19, hospital medicine, workforce planning, surge planning, focus groups, qualitative 相似文献
25.
Tryptophan is metabolized through serotonin, indole, and kynurenine (KN) pathways. Uptake of an excess amount of tryptophan accompanied with vitamin B6 deficiency may result in the accumulation of higher concentrations of metabolites mainly from the KN pathways in the bladder. These metabolites could interact with nitrite to become mutagenic nitrosamines. They could be a promoter in the initiator–promoter model of carcinogenesis. They produced bladder cancer when implanted in the bladder. They also interact with transition metals copper or iron to form reactive radicals or reactive oxygen species (ROS). Some metabolites, 3‐hydroxy‐anthranilic acid, were autooxidized to mutagenic cinnabarinic and anthranilyl radical intermediates. These radical intermediates could also be ligands that interact with aryl hydrocarbon receptor (AhR) and induce xenobiotic metabolizing enzymes (XMEs) to metabolize contaminated carcinogens. When tryptophan is exposed to either visible or UV light, a photoproduct of 6‐formylindolo[3,2b]‐carbazole is formed, which has a very high affinity for the AhR that plays a role in carcinogenesis. This review gives an insight into various mechanisms through which tryptophan metabolites cause carcinogenesis. It could be concluded that tryptophan metabolites play a complementary role in promoting carcinogenesis along with carcinogens like aflatoxin, CCl4, 2‐acetylaminofluorene, 4‐aminobiphenyl, 2‐naphthylamine, or N‐[4‐(5‐nitro‐2‐furyl)?2‐thiazolyl] formamide. The underlying mechanisms could be their autoxidation, exposure to either visible or UV light, interaction with nitrite or transition metals to form reactive intermediates, serving as ligands to interact with an AhR that is known to play a role in carcinogenesis through induction of XMEs. Further research is warranted.Environ. Mol. Mutagen. 52:81–104, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
26.
Nirmal C. Tejwani Richelle C. Takemoto Gopi Nayak Brian Pahk Kenneth A. Egol 《Clinical orthopaedics and related research》2010,468(2):599-604
Distal radius fractures are the most common upper extremity fracture, representing one-sixth of all fractures treated in emergency
departments nationwide. Beyond the initial reduction and immobilization of these fractures, providing proper followup to ensure
maintenance of the reduction and identify complications is necessary for optimal recovery of forearm and wrist functions.
We sought to identify the clinical and demographic factors that characterize patients with distal radius fractures who do
not return for followup and to assess the underlying causes for their poor followup rates. Compared with patients who were
compliant with followup, those lost to followup had lower Physical and Mental Health scores on the SF-36 forms, more often
were treated nonoperatively, and more likely had not surpassed secondary education. However, we found no difference between
these two groups based on age, gender, mechanism of injury, marital status, or hand dominance. Early identification of patients
who potentially are noncompliant can result in additional measures being taken to ensure the patient’s return to the treating
hospital and physicians. This in turn will prevent complications attributable to lack of followup and allow more accurate
assessment of results, thereby improving patient outcomes. 相似文献
27.
Gopalkrishnan R 《Current opinion in investigational drugs (London, England : 2000)》2002,3(12):1773-1777
Introgen, under license from Corixa (formerly GenQuest), is developing INGN-241, a gene therapy based on the mda-7 gene in combination with the company's adenoviral delivery system, for the potential treatment of cancer. A phase I trial for the treatment of solid tumors was initiated at the end of November 2000. 相似文献
28.
The incidence of peripheral pulmonary adenocarcinoma has increased in recent years. Clara cell has been known as target for carcinogens and source of pulmonary tumors. One of the presumed roles of the bronchiolar Clara cell is the secretion of pulmonary surfactant into the bronchiolar lumen. To establish the secretory morphology of Clara cell, a well-defined secretory agonist, isoproterenol (500 mg/kg) and the antagonist, propranolol (20 mg/kg), were administered into five-week old mice. The secretory response was examined at 1 hour and 4 hours after injection. Ultrastructural morphometry was used to quantitate the secretory response by measuring area of apical cap of the Clara cells. Isoproterenol caused a significant increase in area of apical cap of Clara cells 1 and 4 hours after injection (p < 0.0001), while pretreatment with propranolol prevented this effect at 4 hours. Propranolol alone significantly decreased the area of Clara cells (p < 0.0001). Clara cells secretory granules disappeared 1 hour after propranolol plus isoproterenol administration, and the granules reappeared at 4 hours. The accelerated secretion of Clara cells by isoproterenol provides evidence of their secretory mechanism controlled by beta-adrenergic agonists. The study has confirmed the secretory role of Clara cells. The secretion is both apocrine and merocrine type. 相似文献
29.
Tobacco smoking and pulmonary tuberculosis 总被引:12,自引:1,他引:11
BACKGROUND: The prevalence of tuberculosis in adult men in India is 2-4 times higher than in women. Tobacco smoking is prevalent almost exclusively among men, so it is possible that tobacco smoking may be a risk factor for developing pulmonary tuberculosis. A nested case control study was carried out to study the association between tobacco smoking and pulmonary tuberculosis. METHODS: A tuberculosis disease survey was carried out in two Panchayat unions in the Tiruvallur district of Tamil Nadu in India. Eighty five men aged 20-50 years with bacteriological tuberculosis (smear and/or culture positive) were selected as cases and 459 age matched men without tuberculosis were selected randomly as controls. Information on smoking status, type of tobacco smoked, quantity of tobacco smoked, and duration of tobacco smoking was collected from cases and controls using a questionnaire. RESULTS: The estimated crude odds ratio (OR) of the association between tobacco smoking and bacillary tuberculosis was 2.48 (95% confidence interval (CI) 1.42 to 4.37), p<0.001.The age adjusted OR (Mantel-Hanszel estimate) was 2.24.(95% CI 1.27 to 3.94), p<0.05. The ORs for mild (1-10 cigarettes/day), moderate (11-20/day), and heavy (>20/day) smokers were 1.75, 3.17, and 3.68, respectively (p<0.0001 test for linear trend). The ORs for smokers with <10 years, 11-20 years, and >20 years of smoking were 1.72, 2.45, and 3.23, respectively (p<0.0001 test for linear trend). CONCLUSION: There is a positive association between tobacco smoking and pulmonary (bacillary) tuberculosis (OR 2.5). The association also shows a strong dose-response relationship. 相似文献
30.