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1.
Phys Chem Chem Phys ; 25(44): 30458-30468, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37921019

ABSTRACT

More than the permissible limit of acidic gases like CO2, SO2, and NO2 in the atmosphere are responsible for the formation of acid rain, the greenhouse effect and many other undesirable environmental hazards. So, the capture and utilization of these gases are essential for mankind. Herein, we proposed an azo-based square pillared MOF, [Ni(MF5)(1,2-bis(4-pyridy)diazene)2]n, with the CUS metal site, i.e. M = Al/Fe, for the selective capture and conversion of acidic gas molecules into commodity chemicals such as cyclic carbonate, sulphite and nitrite. With the aid of Density Functional Theory (DFT), [Ni(MF5)(1,2-bis(4-pyridy)diazene)2]n has been optimized, and the specific force field is derived via guest-host interaction. The Grand Canonical Monte Carlo (GCMC) simulation has been used to explore the guest-host interactions over a wide range of pressures, and their respective stability under pre-humidification is evaluated. The adsorption prediction reveals that MFFIVE-Ni-apy have a higher adsorptive capacity (37.1 mmol g-1), and especially ALFFIVE-Ni-apy possesses a higher affinity towards guest molecules (CO2, SO2) rather than FEFFIVE-Ni-apy. Additionally, the adsorption of gases in the presence of humidity reveals that ALFFIVE-Ni-apy has an optimal adsorption capacity for all investigated acidic gases even at 38.5 RH%. The absorbed acidic gases on MFFIVE-Ni-apy were used for the theoretical investigations on cycloaddition with the aid of DFT as an application perspective of the toxic gases instead of expelling into atmosphere. The Climbing Image Nudged Elastic Band (CI-NEB) approach was used to discover the transition state in this scenario, in which the cycloaddition of adsorbed CO2, SO2, and NO2 gases with epoxides leads to the formation of cyclic carbonates, sulphites, and nitrates, respectively.

2.
Clin Oncol (R Coll Radiol) ; 35(9): 586-597, 2023 09.
Article in English | MEDLINE | ID: mdl-37225552

ABSTRACT

AIMS: Adding concurrent (chemo)therapy to radiotherapy improves outcomes for muscle-invasive bladder cancer patients. A recent meta-analysis showed superior invasive locoregional disease control for a hypofractionated 55 Gy in 20 fractions schedule compared with 64 Gy in 32 fractions. In the RAIDER clinical trial, patients undergoing 20 or 32 fractions of radical radiotherapy were randomised (1:1:2) to standard radiotherapy or to standard-dose or escalated-dose adaptive radiotherapy. Neoadjuvant chemotherapy and concomitant therapy were permitted. We report exploratory analyses of acute toxicity by concomitant therapy-fractionation schedule combination. MATERIALS AND METHODS: Participants had unifocal bladder urothelial carcinoma staged T2-T4a N0 M0. Acute toxicity was assessed (Common Terminology Criteria for Adverse Events) weekly during radiotherapy and at 10 weeks after the start of treatment. Within each fractionation cohort, non-randomised comparisons of the proportion of patients reporting treatment emergent grade 2 or worse genitourinary, gastrointestinal or other adverse events at any point in the acute period were carried out using Fisher's exact tests. RESULTS: Between September 2015 and April 2020, 345 (163 receiving 20 fractions; 182 receiving 32 fractions) patients were recruited from 46 centres. The median age was 73 years; 49% received neoadjuvant chemotherapy; 71% received concomitant therapy, with 5-fluorouracil/mitomycin C most commonly used: 44/114 (39%) receiving 20 fractions; 94/130 (72%) receiving 32 fractions. The acute grade 2+ gastrointestinal toxicity rate was higher in those receiving concomitant therapy compared with radiotherapy alone in the 20-fraction cohort [54/111 (49%) versus 7/49 (14%), P < 0.001] but not in the 32-fraction cohort (P = 0.355). Grade 2+ gastrointestinal toxicity was highest for gemcitabine, with evidence of significant differences across therapies in the 32-fraction cohort (P = 0.006), with a similar pattern but no significant differences in the 20-fraction cohort (P = 0.099). There was no evidence of differences in grade 2+ genitourinary toxicity between concomitant therapies in either the 20- or 32-fraction cohorts. CONCLUSION: Grade 2+ acute adverse events are common. The toxicity profile varied by type of concomitant therapy; the gastrointestinal toxicity rate seemed to be higher in patients receiving gemcitabine.


Subject(s)
Brachytherapy , Carcinoma, Transitional Cell , Radiation Oncology , Urinary Bladder Neoplasms , Humans , Aged , Urinary Bladder Neoplasms/drug therapy , Urinary Bladder Neoplasms/radiotherapy , Mitomycin , Gemcitabine
4.
Chemistry ; 26(72): 17445-17454, 2020 Dec 23.
Article in English | MEDLINE | ID: mdl-32767456

ABSTRACT

The development of efficient heterogeneous catalysts suitable for carbon capture and utilization (CCU) under mild conditions is a promising step towards mitigating the growing concentration of CO2 in the atmosphere. Herein, we report the construction of a hydrogen-bonded 3D framework, {[Zn(hfipbba)(MA)]⋅3 DMF}n (hfipbba=4,4'-(hexaflouroisopropylene)bis(benzoic acid)) (HbMOF1) utilizing ZnII center, a partially fluorinated, long-chain dicarboxylate ligand (hfipbba), and an amine-rich melamine (MA) co-ligand. Interestingly, the framework possesses two types of 1D channels decorated with CO2 -philic (-NH2 and -CF3 ) groups that promote the highly selective CO2 adsorption by the framework, which was supported by computational simulations. Further, the synergistic involvement of both Lewis acidic and basic sites exposed in the confined 1D channels along with high thermal and chemical stability rendered HbMOF1 a good heterogeneous catalyst for the highly efficient fixation of CO2 in a reaction with terminal/internal epoxides at mild conditions (RT and 1 bar CO2 ). Moreover, in-depth theoretical studies were carried out using periodic DFT to obtain the relative energies for each stage involved in the catalytic reaction and an insight mechanistic details of the reaction is presented. Overall, this work represents a rare demonstration of rational design of a porous ZnII MOF incorporating multiple functional sites suitable for highly efficient fixation of CO2 with terminal/internal epoxides at mild conditions supported by comprehensive theoretical studies.

5.
Eur J Cancer ; 83: 302-312, 2017 09.
Article in English | MEDLINE | ID: mdl-28780466

ABSTRACT

BACKGROUND: Platinum-based combination chemotherapy is standard treatment for the majority of patients with advanced non-small-cell lung cancer (NSCLC). The trial investigates the importance of the choice of platinum agent and dose of cisplatin in relation to patient outcomes. METHODS: The three-arm randomised phase III trial assigned patients with chemo-naïve stage IIIB/IV NSCLC in a 1:1:1 ratio to receive gemcitabine 1250 mg/m2 on days 1 and 8 of a 3-week cycle with cisplatin 80 mg/m2 (GC80) or cisplatin 50 mg/m2 (GC50) or carboplatin AUC6 (GCb6) for a maximum of four cycles. Primary outcome measure was survival time, aiming to test for a difference between treatment arms and also assess non-inferiority with pre-defined margin selected as hazard ratio (HR) of 1.2. Secondary outcome measures included response rate, adverse events and quality of life (QoL). FINDINGS: The trial recruited 1363 patients. Survival time differed significantly across the three treatment arms (p = 0.046) with GC50 worst with median 8.2 months compared to 9.5 for GC80 and 10.0 for GCb6. HRs (adjusted) for GC50 compared to GC80 was 1.13 (95% confidence interval [CI] 0.99-1.29) and for GC50 compared to GCb6 was 1.23 (95% CI: 1.08-1.41). GCb6 was significantly non-inferior to GC80 (HR = 0.93, upper limit of one-sided 95% CI 1.04). Adjusting for QoL did not change the findings. Best objective response rates were 29% (GC80), 20% (GC50) and 27% (GCb6), p < 0.007. There were more dose reductions and treatment delays in the GCb6 arm and more adverse events (60% with at least one grade 3-4 compared to 43% GC80 and 30% GC50). INTERPRETATION: In combination with gemcitabine, carboplatin at AUC6 is not inferior to cisplatin at 80 mg/m2 in terms of survival. Carboplatin was associated with more adverse events and not with better quality of life. Cisplatin at the lower dose of 50 mg/m2 has worse survival which is not compensated by better quality of life. CLINICALTRIALS. GOV IDENTIFIER: NCT00112710. EUDRACT NUMBER: 2004-003868-30. CANCER RESEARCH UK TRIAL IDENTIFIER: CRUK/04/009.


Subject(s)
Antineoplastic Agents/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Carboplatin/administration & dosage , Carcinoma, Non-Small-Cell Lung/pathology , Cisplatin/administration & dosage , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Female , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Proportional Hazards Models , Quality of Life , Survival Analysis , Gemcitabine
6.
Indian Heart J ; 65(6): 666-70, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24407535

ABSTRACT

BACKGROUND: The close relationship between pleural space and pericardial space and the dependence of their pressure kinetics are well known. This study evaluates the effects of increased intra pleural pressure due to pleural effusion on cardiovascular system. METHODS: Forty patients above the age of 12 who had massive unilateral/bilateral pleural effusion due to non-cardiac etiology were included in the study. Therapeutic thoracocentesis was done for massive pleural effusion. The echocardiographic parameters measured before and after thoracocentesis were compared. RESULTS: Mean age of the patients 46.6 years. Out of 40 patients 8 were females (20%). 7 patients had right atrial collapse on echo. 85% of patients had significant flow velocity changes across both tricuspid valve and mitral valve during phases of respiration.11 patients (47.82%) had IVC compressibility of <50% during inspiration. Mean flow velocity respiratory variations across tricuspid valve before thoracocentesis and after thoracocentesis E 45.04 ± 10.3,32 ± 11.3% (p value <0.001), A 53.71 ± 28%, 32.08 ± 12.5% (p < 0.001) across mitral valve E 32.30 ± 12%, 19.78 ± 7.8% (p < 0.001), A 26 ± 11.2%, 21 ± 9.3% (p 0.006) across pulmonary artery 42.63 ± 31.3%, 17.70 ± 6.2% (p < 0.001), across aorta 21.57 ± 11.4%, 14.08 ± 7.6% (p < 0.001). CONCLUSION: Large pleural effusion has a potential to cause adverse impact on the cardiovascular hemodynamics, which could manifest as tamponade physiology. Altered cardiac hemodynamics could be an important contributor in the mechanism of dyspnea in patients with large pleural effusion.


Subject(s)
Cardiac Tamponade/diagnostic imaging , Cardiac Tamponade/surgery , Cardiovascular System/physiopathology , Hemodynamics/physiology , Pleural Effusion/diagnostic imaging , Adolescent , Adult , Cardiac Tamponade/etiology , Cohort Studies , Echocardiography/methods , Female , Follow-Up Studies , Humans , India , Male , Middle Aged , Pericardiocentesis/methods , Pleural Effusion/complications , Radiography, Thoracic/methods , Risk Assessment , Severity of Illness Index , Tertiary Care Centers , Treatment Outcome , Young Adult
7.
J Assoc Physicians India ; 61(11): 853-5, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24974509

ABSTRACT

A 52 year old patient presented with orthostatic dizziness and syncope caused by postural heart block. When the patient was supine, atrioventricular conduction was normal but when she assumed the upright posture she developed advanced atrioventricular block rapidly progressing to complete heart block. We are presenting a case of syncope caused by orthostatic heart block.


Subject(s)
Heart Block/complications , Posture , Reflex/physiology , Syncope/etiology , Electrocardiography , Female , Heart Block/drug therapy , Heart Block/physiopathology , Humans , Middle Aged , Stress, Physiological
8.
J Postgrad Med ; 57(3): 211-3, 2011.
Article in English | MEDLINE | ID: mdl-21941059

ABSTRACT

Prominent ventricular trabeculations are seen in a fetal heart. Isolated ventricular non-compaction (IVNC) is a rare form of primary cardiomyopathy. It usually presents with heart failure, arrhythmias and very rarely with thrombo-embolic manifestation. The left ventricle is involved in the majority of the cases. Echocardiography is the principal modality for the diagnosis of this condition. IVNC may be misdiagnosed as dilated or hypertrophic cardiomyopathy wherein the prognosis and management do differ significantly. We report a case of a 38-year-old male with IVNC involving both the ventricles, who presented very unusually as stroke resulting from a cardiogenic embolus.


Subject(s)
Heart Failure/complications , Heart Ventricles/abnormalities , Stroke/etiology , Adult , Diagnosis, Differential , Echocardiography, Doppler, Color , Fibrinolytic Agents/therapeutic use , Heart Failure/diagnostic imaging , Heart Ventricles/diagnostic imaging , Humans , Male , Stroke/diagnosis , Stroke/drug therapy , Tomography, X-Ray Computed
9.
Echocardiography ; 22(1): 9-13, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15660681

ABSTRACT

OBJECTIVE: Large uncomplicated atrial septal defect (ASD) alters the pulmonary venous flow (PVF) pattern. We aimed to study the role of transthoracic echocardiography (TTE) in estimating the PVF Doppler abnormalities in ASD. By repeating the study soon after ASD closure, we correlated the hemodynamics of atrial shunting with PVF patterns. METHODS: This study was performed in a tertiary care referral teaching hospital in 2003. The TTE PVF patterns of 34 patients with ASD were studied. TTE study was reported by two blinded investigators independently. Surgical closure of ASD was done on eleven patients and the early postoperative PVF Doppler pattern was also studied with TTE. RESULTS: PVF patterns were adequately recorded in 34 of 38 (90%) subjects with ASD with equal male: female ratio (n = 17 each). The mean age of the study group was 21.4 +/- 8.7 years. ASD ranged from 10 to 38 mm in diameter with a mean of 18 +/- 4.2 mm. Continuous antegrade wave (CAW, mean 68.45 +/- 13.6 cm/s) replaced normally occurring S and D waves in all ASD patients. The atrial reversal wave was reduced or absent (mean 20.18 +/- 3.28 cm/sec). After ASD closure, the CAW was replaced by the S (46.18 +/- 7.5 cm/sec) and D waves (57.72 +/- 9.7 cm/sec) with increase in atrial reversal wave to 27.81 +/- 5.1 cm/sec. CONCLUSIONS: The S and D antegrade waves normally seen in PVF are replaced by a continuous antegrade wave in ASD. Atrial reversal wave is also reduced. PVF waveform becomes normal after ASD closure. TTE PVF Doppler pattern can help estimate ASD hemodynamics.


Subject(s)
Echocardiography, Doppler, Color/methods , Heart Septal Defects, Atrial/diagnostic imaging , Pulmonary Circulation/physiology , Pulmonary Veins/diagnostic imaging , Adolescent , Adult , Blood Flow Velocity/physiology , Female , Heart Septal Defects, Atrial/physiopathology , Humans , Male , Myocardial Contraction/physiology , Retrospective Studies
10.
Indian Heart J ; 53(2): 211-3, 2001.
Article in English | MEDLINE | ID: mdl-11428481

ABSTRACT

Isolated congenital ventricular diverticulum or aneurysm is rare and usually arises from the left ventricle. The presentation of this condition is diverse. We report three cases of isolated congenital left ventricular diverticula. The age range was 17-30 years. Chest X-ray provided the earliest clinical suspicion in these three cases of a cardiac anomaly which was diagnosed by echocardiography and confirmed by angiocardiography. The location of the congenital left ventricular diverticulum was the left ventricular apex in two cases and basal in the other. We conclude that congenital left ventricular diverticulum is a disease of protean presentations. A high index of suspicion is necessary while interpreting chest X-rays and echocardiographs to diagnose congenital left ventricular diverticulum. A contractile accessory chamber of the left ventricle with a narrow neck with or without midline defects and an electrocardiogram without Q waves is consistent with the diagnosis of congenital left ventricular diverticulum.


Subject(s)
Diverticulum/congenital , Diverticulum/diagnosis , Heart Diseases/congenital , Heart Diseases/diagnosis , Adolescent , Adult , Angiography/methods , Diverticulum/surgery , Echocardiography, Doppler/methods , Electrocardiography , Female , Follow-Up Studies , Heart Diseases/surgery , Heart Ventricles , Humans , Male , Vascular Surgical Procedures/methods
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