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1.
Langmuir ; 40(5): 2745-2753, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38279959

RESUMEN

Given the need, both academic and industrial, for new approaches and technologies for chiral discrimination of enantiomers, the present work demonstrates the development through rational design and integration of two new chiral platforms (molecular and membranous) for enantioselective recognition through visual as well as microscopic observation. The molecular platform (TPT) is based on the tryptophan derivative developed through the condensation of two tryptophan units with terepthaloyl chloride. While TPT based on l-tryptophan recognizes R-mandelic acid over the S-isomer, the host with reverse chirality (TPDT) recognizes S-mandelic acid over R-isomer. The role of chemical functionality in this sensitive recognition process was established experimentally by developing an analogue of TPT and by judiciously using different chiral analytes. Importantly, a detailed theoretical study at the molecular level revealed the U-shaped conformation of TPT, creating a cavity for accommodating a chiral guest with selective functional interaction resulting in the discrimination of enantiomers. Finally, a chiral polymeric mat of poly(methyl methacrylate) (PMMA)/polyacrylonitrile (PAN) (2:3) impregnated with TPT was developed via electrospinning. The resulting fibrous mat was successfully utilized for chiral recognition through microscopic and architectural observation. Hence, the present work reports simple chiral tools for enantiomeric recognition.

2.
World J Crit Care Med ; 12(4): 188-203, 2023 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-37745257

RESUMEN

Sepsis is defined as a life-threatening organ dysfunction caused by the dysregulated host response to infection. It is a complex syndrome and is characterized by physiologic, pathologic and biochemical abnormalities in response to an infection. Diagnosis of sepsis is based on history, physical examination and other investigations (including biomarkers) which may help to increase the certainty of diagnosis. Biomarkers have been evaluated in the past for many diseases and have been evaluated for sepsis as well. Biomarkers may find a possible role in diagnosis, prognostication, therapeutic monitoring and anti-microbial stewardship in sepsis. Since the pathophysiology of sepsis is quite complex and is incompletely understood, a single biomarker that may be robust enough to provide all information has not been found as of yet. However, many biomarkers have been studied and some of them have applications at the bedside and guide clinical decision-making. We evaluated the PubMed database to search for sepsis biomarkers for diagnosis, prognosis and possible role in antibiotic escalation and de-escalation. Clinical trials, meta-analyses, systematic reviews and randomized controlled trials were included. Commonly studied biomarkers such as procalcitonin, Soluble urokinase-type plasminogen activator (Supar), presepsin, soluble triggering receptor expressed on myeloid cells 1, interleukin 6, C-reactive protein, etc., have been described for their possible applications as biomarkers in septic patients. The sepsis biomarkers are still an area of active research with newer evidence adding to the knowledge base continuously. For patients presenting with sepsis, early diagnosis and prompt resuscitation and early administration of anti-microbials (preferably within 1 h) and source control are desired goals. Biomarkers may help us in the diagnosis, prognosis and therapeutic monitoring of septic patients. The marker redefining our view on sepsis is yet a mirage that clinicians and researchers continue to chase.

3.
Indian J Crit Care Med ; 26(3): 261-263, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35519922

RESUMEN

Gupta R, Ray S. Advances in Microcirculatory Assessment: A Game Changer in Sepsis Management or the Latest Fad? Indian J Crit Care Med 2022;26(3):261-263.

4.
Org Biomol Chem ; 20(2): 410-414, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34904614

RESUMEN

A Brønsted acid-catalyzed asymmetric Mannich-type addition of 1,3-diones to cyclic N-acyl ketimines is reported for the synthesis of enantioenriched isoindolinones. Various dicarbonyl-substituted isoindolinones bearing a quaternary carbon stereocenter were synthesized with excellent yields (up to 98%) and moderate to high enantioselectivities (up to 95% ee), and most of them possess a fluorine atom at the reactive center. Furthermore, the synthetic utility of the protocol has been demonstrated by the debenzoylation of the product.

5.
Indian J Crit Care Med ; 25(11): 1280-1285, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34866826

RESUMEN

INTRODUCTION: There is strong evidence for the use of corticosteroid in the management of severe coronavirus disease-2019 (COVID-19). However, there is still uncertainty about the timing of corticosteroids. We undertook a modified Delphi study to develop expert consensus statements on the early identification of a subset of patients from non-severe COVID-19 who may benefit from using corticosteroids. METHODS: A modified Delphi was conducted with two anonymous surveys between April 30, 2021, and May 3, 2021. An expert panel of 35 experts was selected and invited to participate through e-mail. The consensus was defined as >70% votes in multiple-choice questions (MCQ) on Likert-scale type statements, while strong consensus as >90% votes in MCQ or >50% votes for "very important" on Likert-scale questions in the final round. RESULTS: Twenty experts completed two rounds of the survey. There was strong consensus for the increased work of breathing (95%), a positive six-minute walk test (90%), thorax computed tomography severity score of >14/25 (85%), new-onset organ dysfunction (using clinical or biochemical criteria) (80%), and C-reactive protein >5 times the upper limit of normal (70%) as the criteria for patients' selection. The experts recommended using oral or intravenous (IV) low-dose corticosteroids (the equivalent of 6 mg/day dexamethasone) for 5-10 days and monitoring of oxygen saturation, body temperature, clinical scoring system, blood sugar, and inflammatory markers for any "red-flag" signs. CONCLUSION: The experts recommended against indiscriminate use of corticosteroids in mild to moderate COVID-19 without the signs of clinical worsening. Oral or IV low-dose corticosteroids (the equivalent of 6 mg/day dexamethasone) for 5-10 days are recommended for patients with features of disease progression based on clinical, biochemical, or radiological criteria after 5 days from symptom onset under close monitoring. HOW TO CITE THIS ARTICLE: How to cite this article: Nasa P, Chaudhry D, Govil D, Daga MK, Jain R, Chhallani AA, et al. Expert Consensus Statements on the Use of Corticosteroids in Non-severe COVID-19. Indian J Crit Care Med 2021;25(11):1280-1285.

6.
Org Lett ; 23(16): 6504-6509, 2021 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-34351776

RESUMEN

Quinine derived bifunctional urea catalyzed cascade Michael-acyl transfer reaction of 5-alkenyl thiazolones and monofluorinated ß-diketones has been developed. The fluorine containing 4-acyloxy thiazoles were synthesized in high yields and good diastereo-and excellent enantioselectivities. Synthetic transformations, including synthesis of 4-hydroxy thiazoles, have been demonstrated.

7.
Polymers (Basel) ; 13(11)2021 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-34205188

RESUMEN

The ongoing global pandemic has bestowed high priority uponthe separation of air-borne particulate matters (PMs), aerosols, etc. using nonwoven fibrous materials, especially for face masks as a means of personal protection. Although spunbond or meltblown nonwoven materials are amongst the forerunners for polymer microfiber-based face mask or air filter development in mass scale, relatively new process of nonwoven manufacturing such as electrospinning is gaining a lot of momentum amongst the filter membrane manufacturers for its scalability of nanofiber-based filter membrane fabrication. There are several nanofiber-based face masks developing industries, which claim a very high efficiency in filtration of particulate matters (PM0.1-10) as well as other aerosols for their products. Polyvinylidene fluoride (PVDF), which is commonly known for its use of tactile sensors and energy harvesters, due to its piezoelectric property, is slowly gaining popularity among researchers and developers as an air filter material. Electrospun PVDF nanofibers can be as fine as 50 nm in mass scale, which allows the membrane to have large surface area compared to its volume, enhancing nanofiber-PM interaction. At the same time, the breathability index can be improved through these PVDF nanofiber membranes due to their architectural uniqueness that promotes slip flow around the fibers. The conductive nature of PVDF makes it advantageous as a promising electret filter allowing better capturing of ultrafine particles. This review aims to provide a comprehensive overview of such PVDF nanofiber-based filter membranes and their roles in air filtration, especially its application in filtrate of air-borne PMs.

8.
Indian J Crit Care Med ; 25(7): 773-779, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34316171

RESUMEN

OBJECTIVES: "Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock: 2016" provides guidelines in regard to prompt management and resuscitation of sepsis or septic shock. The study is aimed to assess the robustness of randomized controlled trials (RCTs) that formulate these guidelines in terms of fragility index and reverse fragility index. METHOD: RCTs that contributed to these guidelines having parallel two-group design, 1:1 allocation ratio, and at least one dichotomous outcome were included in the study. The median fragility index was calculated for RCTs with significant statistical outcomes, whereas the median reverse fragility index was calculated for RCTs with nonsignificant statistical results. RESULTS: Hundred RCTs that met the inclusion criteria were analyzed. The median fragility index was 5.5 [95% confidence interval (CI) 1-30] and median reverse fragility index was 13 (95% CI 12.07-16.8) at a p value of 0.05. The median reverse fragility index was 16 (95% CI 10-26) at a p value of 0.01. Most of the RCTs included in this analysis were of good quality, having a median Jadad score of 6. CONCLUSION: This analysis found that the surviving sepsis guidelines were based on highly robust RCTs with statistically insignificant results and on some moderately robust RCTs with statistically significant results. RCTs with statistically insignificant results were more robust than RCTs with statistically significant results in regard to these guidelines. HIGHLIGHTS: The study assessed the robustness of randomized controlled trials (RCTs) that were used to formulate surviving sepsis guidelines. Most RCTs showed statistically nonsignificant results. RCTs with statistically significant results were moderately fragile whereas RCTs with nonsignificant results were more robust. HOW TO CITE THIS ARTICLE: Choupoo NS, Das SK, Saikia P, Dey S, Ray S. How Robust are the Evidences that Formulate Surviving Sepsis Guidelines? An Analysis of Fragility and Reverse Fragility of Randomized Controlled Trials that were Referred in these Guidelines. Indian J Crit Care Med 2021;25(7):773-779.

9.
Org Biomol Chem ; 19(21): 4685-4690, 2021 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-33982725

RESUMEN

An (R)-DM-BINAP/Cu(CH3CN)4BF4 complex catalyzed exo-selective asymmetric 1,3-dipolar cycloaddition (1,3-DCA) reaction of imino esters with α,ß-unsaturated pyrazoleamides has been developed. A series of highly functionalized pyrrolidines with multiple stereogenic centers were obtained with good yields and diastereoselectivities and excellent enantioselectivities (up to 99% ee).

10.
Indian J Crit Care Med ; 24(8): 615-616, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33024361

RESUMEN

How to cite this article: Das S, Ray S. Mottling, Lactate, and the Microcirculation in Sepsis: Are We Back to Bedside Clinical Assessment after the Honeymoon with Technology? Indian J Crit Care Med 2020;24(8):615-616.

13.
Indian J Crit Care Med ; 24(4): 245-251, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32565634

RESUMEN

INTRODUCTION: Differentiation between sepsis and systemic inflammation response syndrome (SIRS) remains a diagnostic challenge for clinicians as both may have similar clinical presentation. A quick and accurate diagnostic tool that can discriminate between these two conditions would aid in appropriate therapeutic decision-making. This prospective study was conducted to evaluate the diagnostic and prognostic utility of soluble urokinase-type plasminogen activator receptor (suPAR) and procalcitonin (PCT) in sepsis and SIRS patients. MATERIALS AND METHODS: Eighty-eight patients were enrolled, of which 29 were SIRS and 59 were sepsis patients. The levels of suPAR and PCT were measured on the day of admission (day 1), day 3, and day 7. RESULTS: The levels of suPAR and PCT were significantly higher (p = 0.05 and p < 0.001, respectively) in sepsis group as compared to the SIRS group. The soluble urokinase-type plasminogen activator receptor was a better diagnostic tool in predicting sepsis over PCT [area under curve (AUC) 0.89 vs 0.82] on day 1. The best cutoff for suPAR was 5.58 pg/mL [96% sensitivity and 90% negative predictive value (NPV)] and the best cut-off for PCT was 1.96 ng/mL (93.1% sensitivity and 80% NPV). However, PCT had better prognostic trends (p = 0.006) to identify nonsurvivors in sepsis group. CONCLUSION: Our findings suggest that both suPAR and PCT can be used as potential test tools to differentiate between SIRS and sepsis. Procalcitonin showed significant prognostic trends to identify nonsurvivors. The soluble urokinase-type plasminogen activator receptor showed better diagnostic potential than PCT on day 1. CLINICAL SIGNIFICANCE: Both suPAR and PCT can be used as surrogate biomarkers to distinguish sepsis from SIRS. Procalcitonin showing a significant prognostic trend to identify nonsurvivors can help the clinicians to take relevant clinical decisions. Also, the use of biomarkers like PCT and suPAR could reduce the inappropriate use of antibiotics in noninfective SIRS. HOW TO CITE THIS ARTICLE: Sharma A, Ray S, Mamidipalli R, Kakar A, Chugh P, Jain R, et al. A Comparative Study of the Diagnostic and Prognostic Utility of Soluble Urokinase-type Plasminogen Activator Receptor and Procalcitonin in Patients with Sepsis and Systemic Inflammation Response Syndrome. Indian J Crit Care Med 2020;24(4):245-251.

14.
Indian J Crit Care Med ; 24(Suppl 1): S6-S30, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32205954

RESUMEN

BACKGROUND AND PURPOSE: Short-term central venous catheterization (CVC) is one of the commonly used invasive interventions in ICU and other patient-care areas. Practice and management of CVC is not standardized, varies widely, and need appropriate guidance. Purpose of this document is to provide a comprehensive, evidence-based and up-to-date, one document source for practice and management of central venous catheterization. These recommendations are intended to be used by critical care physicians and allied professionals involved in care of patients with central venous lines. METHODS: This position statement for central venous catheterization is framed by expert committee members under the aegis of Indian Society of Critical Care Medicine (ISCCM). Experts group exchanged and reviewed the relevant literature. During the final meeting of the experts held at the ISCCM Head Office, a consensus on all the topics was made and the recommendations for final document draft were prepared. The final document was reviewed and accepted by all expert committee members and after a process of peer-review this document is finally accepted as an official ISCCM position paper.Modified grade system was utilized to classify the quality of evidence and the strength of recommendations. The draft document thus formulated was reviewed by all committee members; further comments and suggestions were incorporated after discussion, and a final document was prepared. RESULTS: This document makes recommendations about various aspects of resource preparation, infection control, prevention of mechanical complication and surveillance related to short-term central venous catheterization. This document also provides four appendices for ready reference and use at institutional level. CONCLUSION: In this document, committee is able to make 54 different recommendations for various aspects of care, out of which 40 are strong and 14 weak recommendations. Among all of them, 42 recommendations are backed by any level of evidence, however due to paucity of data on 12 clinical questions, a consensus was reached by working committee and practice recommendations given on these topics are based on vast clinical experience of the members of this committee, which makes a useful practice point. Committee recognizes the fact that in event of new emerging evidences this document will require update, and that shall be provided in due time. ABBREVIATIONS LIST: ABHR: Alcohol-based hand rub; AICD: Automated implantable cardioverter defibrillator; BSI: Blood stream infection; C/SS: CHG/silver sulfadiazine; Cath Lab: Catheterization laboratory (Cardiac Cath Lab); CDC: Centers for Disease Control and Prevention; CFU: Colony forming unit; CHG: Chlorhexidine gluconate; CL: Central line; COMBUX: Comparison of Bedside Ultrasound with Chest X-ray (COMBUX study); CQI: Continuous quality improvement; CRBSI: Catheter-related blood stream infection; CUS: Chest ultrasonography; CVC: Central Venous Catheter; CXR: Chest X-ray; DTTP: Differential time to positivity; DVT: Deep venous thrombosis; ECG: Electrocardiography; ELVIS: Ethanol lock and risk of hemodialysis catheter infection in critically ill patients; ER: Emergency room; FDA: Food and Drug Administration; FV: Femoral vein; GWE: Guidewire exchange; HD catheter: Hemodialysis catheter; HTS: Hypertonic saline; ICP: Intracranial pressure; ICU: Intensive Care Unit; IDSA: Infectious Disease Society of America; IJV: Internal jugular vein; IPC: Indian penal code; IRR: Incidence rate ratio; ISCCM: Indian Society of Critical Care Medicine; IV: Intravenous; LCBI: Laboratory confirmed blood stream infection; M/R: Minocycline/rifampicin; MBI-LCBI: Mucosal barrier injury laboratory-confirmed bloodstream infection; MRSA: Methicillin-resistant Staphylococcus aureus; NHS: National Health Service (UK); NHSN: National Healthcare Safety Network (USA); OT: Operation Theater; PICC: Peripherally-inserted central catheter; PIV: Peripheral intravenous line; PL: Peripheral line; PVI: Povidone-iodine; RA: Right atrium; RCT: Randomized controlled trial; RR: Relative risk; SCV/SV: Subclavian vein; ScVO2: Central venous oxygen saturation; Sn: Sensitivity; SOP: Standard operating procedure; SVC: Superior vena cava; TEE: Transesophageal echocardiography; UPP: Useful Practice Points; USG: Ultrasonography; WHO: World Health Organization. HOW TO CITE THIS ARTICLE: Javeri Y, Jagathkar G, Dixit S, Chaudhary D, Zirpe KG, Mehta Y, et al. Indian Society of Critical Care Medicine Position Statement for Central Venous Catheterization and Management 2020. Indian J Crit Care Med 2020;24(Suppl 1):S6-S30.

15.
Polymers (Basel) ; 12(1)2020 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-31963805

RESUMEN

With the per capita growth of energy demand, there is a significant need for alternative and sustainable energy resources. Efficient electrochemical catalysis will play an important role in sustaining that need, and nanomaterials will play a crucial role, owing to their high surface area to volume ratio. Electrospun nanofiber is one of the most promising alternatives for producing such nanostructures. A section of key nano-electrocatalysts comprise of transition metals (TMs) and their derivatives, like oxides, sulfides, phosphides and carbides, etc., as well as their 1D composites with carbonaceous elements, like carbon nanotubes (CNTs) and carbon nanofiber (CNF), to utilize the fruits of TMs' electronic structure, their inherent catalytic capability and the carbon counterparts' stability, and electrical conductivity. In this work, we will discuss about such TM derivatives, mostly TM-based ceramics, grown on the CNF substrates via electrospinning. We will discuss about manufacturing methods, and their electrochemical catalysis performances in regards to energy conversion processes, dealing mostly with water splitting, the metal-air battery fuel cell, etc. This review will help to understand the recent evolution, challenges and future scopes related to electrospun transition metal derivative-based CNFs as electrocatalysts.

16.
Indian J Crit Care Med ; 24(11): 1106-1113, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33384519

RESUMEN

PURPOSE: The present study systematically searched important medical databases, assessed the quality of available pieces of evidence, and performed a meta-analysis to test the efficacy of different therapeutic options currently available for treating COVID-19. MATERIALS AND METHODS: PubMed, CNKI, LILACS, Koreamed, WHO clinical trial registry, and medRxiv were searched since December 2019. Any observational or controlled study that tested the efficacy of any pharmacological intervention in COVID-19 patients either prospectively or retrospectively was included in the qualitative analysis. We assessed outcomes as dichotomous variables, i.e., a patient having a positive clinical outcome. Relative risks/risk ratios (RR) having a 95% confidence interval (CI) were derived. Studies conforming to inclusion criteria were pooled using the random-effect model. RESULTS: Nine trials on hydroxychloroquine (HCQ), six studies on antiviral, four studies on monoclonal antibodies, two on corticosteroids, two on convalescent plasma (CP), and one on interferon-α2b were included in the systematic review. Meta-analysis containing six scientific trials and analyzing 522 patients revealed that the relative risk of positive clinical outcomes with HCQ treatment was 1.042 (95% CI, 0.884 to 1.874) with a number needed to treat (NNT) of 12.6. A meta-analysis of two studies analyzing 285 patients showed that the relative risk of clinical resolution with lopinavir and ritonavir combination was 1.152 (95% CI 0.709 to 1.87). Out of various antiviral used, the only remdesivir showed a positive result in a case series. Monoclonal antibodies showed decreased C-reactive protein, decreased oxygen, and ventilator requirements. A corticosteroid may increase mortality with increased dose. Two small case series on CP showed some promising results. CONCLUSION: The study showed slightly favorable results with HCQ, monoclonal antibodies, remdesivir, and CP in treating COVID-19 patients. Further research is warranted in establishing the efficacy of studied interventions. PROSPERO IDENTIFIER: CRD42020180979. HOW TO CITE THIS ARTICLE: Choupoo NS, Das SK, Haldar R, Sarkar H, Tewari R, Ray S. Evaluating the Efficacy and Safety of the Existing Repurposed Pharmacological Agents for Treating COVID-19: A Meta-analysis and Systematic Review of Clinical Trials. Indian J Crit Care Med 2020;24(11):1106-1113.

17.
J Org Chem ; 84(24): 15865-15876, 2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31741383

RESUMEN

BF3·OEt2-catalyzed nucleophilic addition of vinyl azides to in situ generated N-acyl iminium salts obtained from 3-hydroxyisoindolinones is described in this article. The procedure is operationally simple, mild, additive, and metal-free. The reaction proceeds smoothly at ambient temperature with a wide range of 3-hydroxyisoindol-1-ones and vinyl azides to afford 3-oxoisoindoline-1-acetamides (32 examples) in high yields (up to 97%). Furthermore, the synthetic utility of this methodology is depicted by exploiting the reactivity of an amide functionality in the products.

18.
Indian J Crit Care Med ; 23(Suppl 3): S226-S229, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31656384

RESUMEN

How to cite this article: Das SK, Reddy MM, Ray S. Hemostatic Agents in Critically Ill Patients. Indian J Crit Care Med 2019;23(Suppl 3):S226-S229.

19.
Org Lett ; 21(2): 417-422, 2019 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-30624068

RESUMEN

Chiral Brønsted acid catalyzed enantioselective syntheses of isoindolinones and phthalides have been accomplished via tandem Mannich-lactamization and aldol-lactonization reactions, respectively. A variety of enantioenriched isoindolinones (up to 99% ee) and phthalides (up to 85% ee) containing α-diazoesters were afforded in excellent yields. Furthermore, a concise synthesis of ( S)-PD 172938 has been demonstrated by using this protocol.

20.
Chem Commun (Camb) ; 54(28): 3516-3519, 2018 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-29564434

RESUMEN

A chiral phosphoric acid-catalyzed asymmetric Mannich-type reaction of α-diazo esters with in situ generated N-acyl ketimines, derived from 3-hydroxyisoindolinones has been demonstrated in this communication. A variety of isoindolinone-based α-amino diazo esters bearing a quaternary stereogenic center were afforded in high yields (up to 99%) with excellent enantioselectivities (up to 99% ee). Furthermore, the synthetic utility of the products has been depicted by the hydrogenation of the diazo moiety of adducts.

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