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41.
Urvish Patel Preeti Malik Deep Mehta Priyanka Rajput Mashu Shrivastava Madiha Naveed Eseosa Urhoghide Mehwish Martin Shamima Somi Richa Jaiswal Achint Patel Avantika Israni Jagmeet Singh Asim Kichloo Shamik Shah Abhishek Lunagariya 《Journal of stroke and cerebrovascular diseases》2021,30(7):105805
IntroductionThere is limited literature on coronavirus disease 2019 (COVID -19) complications such as thromboembolism, cardiac complications etc. as possible trigger for stroke. Hence, we aim to evaluate the prevalence and outcomes of COVID-19 related cardiovascular complications and secondary infection and their possibility as potential triggers for the stroke.MethodsData from observational studies describing the complications [acute cardiac injury (ACI), cardiac arrhythmias (CA), disseminated intravascular coagulation (DIC), septic shock, secondary infection] and outcomes of COVID‐19 hospitalized patients from December 1, 2019 to June 30, 2020, were extracted following PRISMA guidelines. Adverse outcomes defined as intensive care units, oxygen saturation less than 90%, invasive mechanical ventilation, severe disease, and in‐hospital mortality. The odds ratio and 95% confidence interval were obtained, and forest plots were created using random‐effects models. A short review of these complications as triggers of stroke was conducted.Results16 studies with 3480 confirmed COVID-19 patients, prevalence of ACI [38%vs5.9%], CA [26%vs5.3%], DIC [4%vs0.74%], septic shock [18%vs0.36%], and infection [30%vs12.5%] was higher among patients with poor outcomes. In meta-analysis, ACI [aOR:9.93(95%CI:3.95–25.00], CA [7.52(3.29–17.18)], DIC [7.36(1.24–43.73)], septic shock [30.12(7.56–120.10)], and infection [10.41(4.47–24.27)] had higher odds of adverse outcomes. Patients hospitalized with acute ischemic stroke and intracerebral hemorrhage, had complications like pulmonary embolism, venous thromboembolism, DIC, etc. and had poor outcomesConclusionThe complications like acute cardiac injury, cardiac arrhythmias, DIC, septic shock, and secondary infection had poor outcomes. Patients with stroke were having history of these complications. Long term monitoring is required in such patients to prevent stroke and mitigate adverse outcomes. 相似文献
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Maheshkumar N Upasani Supriya Chopra Reena Engineer Umesh Mahantshetty Seema Medhi Zubin Mehta Shyam K Shrivastava 《The British journal of radiology》2015,88(1054)
Objective:
The outcome of post-surgical recurrences of cervical cancer may be improved through radiation dose escalation, which hinges on accurate identification and treatment of the target. The present study quantifies target motion during course of image-guided radiotherapy (IGRT) for vault cancers.Methods:
All patients underwent planning CT simulation after bladder-filling protocol. A daily pre-treatment megavoltage CT was performed. All translations and rotations were recorded. Post-registration displacement of gross tumour volume (GTV) and centre of mass (COM) of GTV was independently recorded by two observers for fractions one to seven. Day 1 image sets served as reference images against which the displacements of COM were measured. We calculated the displacements of common volume (CV) and encompassing volume (EV) of GTV for both the observers.Results:
A total of 90 image data sets of 15 patients were available for evaluation. Individual patient GTV and average GTV by both the observers were comparable. The average shifts for EV were 2.4 mm [standard deviation (SD) ±1.2] in the mediolateral, 4.2 mm (SD ±2.8) in the anteroposterior and 4.0 mm (SD ±2.1) in superoinferior directions. Similarly, the average shifts for CV were 1.9 mm (SD ±0.6) in the mediolateral, 3.7 mm (SD ±2.7) in the anteroposterior and 4.4 mm (SD ±2.7) in superoinferior directions. Using Stroom''s/van Herk''s formula, the minimum recommended margins would be 4.5/5.2, 8.2/9.4 and 7.3/8.3 mm, respectively, for lateral, anteroposterior and superoinferior directions.Conclusion:
Differential directional internal margin is recommended in patients undergoing IGRT for post-surgical recurrence of cervical cancers.Advances in knowledge:
Internal organ motion of vault cancers can be accounted for by a directional margin to the gross tumour. 相似文献44.
R S Vasan S Shrivastava M V Kumar 《Journal of the American College of Cardiology》1992,20(6):1362-1370
OBJECTIVES. Our objective was to compare the Doppler pressure half-time, Doppler continuity equation and two-dimensional echocardiographic planimetric methods of estimating mitral valve area in Lutembacher syndrome. BACKGROUND. Fluid dynamics theory predicts that mitral pressure half-time varies inversely with mitral valve area and directly with net chamber compliance and the peak early diastolic transmitral gradient in pure mitral stenosis. The effects of an atrial shunt on these interrelations have not been investigated. METHODS. Correlation and agreement between mitral valve area estimates obtained by the three methods and that obtained by cardiac catheterization was ascertained in 11 patients with Lutembacher syndrome. RESULTS. Valve areas determined by planimetry and the continuity equation method correlated and agreed well with catheterization measurements (r = 0.83 and 0.81, respectively). The pressure half-time method consistently overestimated mitral valve area; the extent of overestimation was greater in patients with larger atrial shunts. The hemodynamic pressure half-time was independent of the mitral valve area, chamber compliance and the peak transmitral gradient. It was dependent on the magnitude of the atrial shunt, although the correlation obtained was only fair (r = 0.61). CONCLUSIONS. These findings suggest that the Doppler pressure half-time method is an inaccurate measure of mitral valve area whenever an atrial shunt coexists with mitral stenosis. Planimetry and the Doppler continuity equation methods yield accurate estimates of mitral valve area in Lutembacher syndrome. 相似文献
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Aruna Bhawna Rani Suman Swami Arunava Agarwala Debasis Behera Rahul Shrivastava 《RSC advances》2019,9(52):30599
2,3-Diaminomaleonitrile (DAMN) has proved to be a valuable organic π-conjugated molecule having many applications in the area of chemosensors for sensing of ionic and neutral species because of its ability to act as a building block for well-defined molecular architectures and scaffolds for preorganised arrays of functionality. In this article, we discussed the utilization of 2,3-diaminomaleonitrile (DAMN) for the design and development of chemosensor molecules and their application in the area of metal ion, anion and reactive oxygen species sensing. Along with these, we present different examples of DAMN based chemosensors for multiple ion sensing. We also discuss the ion sensing mechanism and potential uses in other related areas of research.2,3-Diamniomaleonitrile (DAMN) is valuable π-conjugated organic scaffold molecule for designing of efficient chemosensors for sensing of ionic and Reactive Oxygen Species (ROS). 相似文献
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49.
Zhu B Shrivastava A Luongo C Chen T Harney JW Marsili A Tran TV Bhadouria A Mopala R Steen AI Larsen PR Zavacki AM 《The Journal of endocrinology》2012,214(1):87-94
Previously, it was shown that the type 1 deiodinase (D1) is subject to substrate-dependent inactivation that is blocked by pretreatment with the inhibitor of D1 catalysis, propylthiouracil (PTU). Using HepG2 cells with endogenous D1 activity, we found that while considerable D1-mediated catalysis of reverse tri-iodothyronine (rT(3)) is observed in intact cells, there was a significant loss of D1 activity in sonicates assayed from the same cells in parallel. This rT(3)-mediated loss of D1 activity occurs despite no change in D1 mRNA levels and is blocked by PTU treatment, suggesting a requirement for catalysis. Endogenous D1 activity in sonicates was inactivated in a dose-dependent manner in HepG2 cells, with a ~50% decrease after 10?nM rT(3) treatment. Inactivation of D1 was rapid, occurring after only half an hour of rT(3) treatment. D1 expressed in HEK293 cells was inactivated by rT(3) in a similar manner. (75)Se labeling of the D1 selenoprotein indicated that after 4?h rT(3)-mediated inactivation of D1 occurs without a corresponding decrease in D1 protein levels, though rT(3) treatment causes a loss of D1 protein after 8-24?h. Bioluminescence resonance energy transfer studies indicate that rT(3) exposure increases energy transfer between the D1 homodimer subunits, and this was lost when the active site of D1 was mutated to alanine, suggesting that a post-catalytic structural change in the D1 homodimer could cause enzyme inactivation. Thus, both D1 and type 2 deiodinase are subject to catalysis-induced loss of activity although their inactivation occurs via very different mechanisms. 相似文献
50.
Pneumosinus dilatans (PD) represents a rare lesion of unknown etiology in which progressive enlargement of an air-filled paranasal sinus results in cosmetic and functional complications. The absence of pathologic mucosa has traditionally been considered a hallmark of this disorder. A 24-year-old man presented with 2 years of chronic rhinosinusitis and recurrent, acute episodes of severe forehead pain with worsening outward prominence of the frontal sinus during air travel. Computed tomography and findings at surgery were notable for diffuse nonpolypoid inflammatory changes of the paranasal sinuses, a type III frontal sinus cell, and PD of the frontal sinus with severe deformity and thinning of the anterior table. A bicoronal approach was used for frontal sinus obliteration and cranioplasty. Excellent cosmetic and functional results were noted at the last follow-up. To our knowledge, this is the first report of PD frontalis presenting in the setting of chronic rhinosinusitis. Surgical management of this disorder requires consideration of both the functional and cosmetic issues. 相似文献