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61.

Ethnopharmacological relevance

The bark of Tecomella undulata is primarily used in the treatment of syphilis, painful swellings and cancer by traditional healers. Also, it is claimed to be useful in treating urinary discharges, enlargement of spleen, leucorrhoea, leukoderma, tumors, liver disorders, gonorrhea, gout and promotes wound healing in Indian traditional system of medicine.

Aim

To establish a scientific validation for the antitumor effects of Tecomella undulata bark and explore the mechanistic pathway in chronic myeloid leukemia cell line, K562. The study was further extended to standardize the extract using quercetin as biomarker.

Methods

Induction of apoptosis by chloroform extract of Tecomella undulata bark (CTUB) was determined by MTT, Annexin V and caspase activation assays. The cell cycle analysis was done by flow cytometer and nuclear staining by DAPI. The standardization of the extract was performed through reverse phase-HPLC method under PDA detection.

Result

Results clearly showed the induction of apoptosis by CTUB in K562 cells. The effect was found to be dose dependent, having IC50 of 30 μg/ml with activation of FAS, FADD, caspase 8, caspase 3/7 and fragmentation of DNA. The bioactive CTUB was determined to possess 0.03% (w/w) of quercetin.

Conclusion

The investigation clearly demonstrated the potential antitumor effect of CTUB, thereby validating the traditional claim. Quercetin, known to have anticancer activity is being reported and quantified for the first time from the bark of Tecomella undulata.  相似文献   
62.
ICG fluorescence (ICGF) guidance during laparoscopic cholecystectomy (LC) is gaining wider acceptance. While the accruing data largely addresses ICGF guidance during LC in patients with uncomplicated gallstone disease (UGS) and acute cholecystitis, there is a paucity of data related for complicated gall stone disease (CGS) such as choledocholithiasis, bilio-enteric fistula, remnant gall bladder, etc. The purpose of this study was to evaluate the role of ICGF during LC in the spectrum of CGS with state of the art 4 chip camera system. Retrospective review from a prospectively maintained database of all patients who underwent ICGF guided LC during the period June 1st, 2019 till December 30th, 2021 formed part of the study. Clinical profile and findings on ICGF during LC for CGS were studied. The data was studied to evaluate the potential roles of ICGF during LC for CGS. Of 68 patients, there were 29 males and 39 females. Among them were 32 and 36 in the uncomplicated and complicated gallstone disease groups, respectively. ICGF showed CBD visualization in 67(98.5%) and cystic duct in 62(91%). ICGF guidance helped in management of CGS, prior to, during and after completion of LC. It had novel application in patients undergoing CBD exploration. In our small series of patients with CGS, ICGF guidance enabled a LC and laparoscopic subtotal cholecystectomy in 94% and 6% of patients respectively. The study highlights potential roles and advantages with ICGF guided laparoscopic management for CBD stones, bilioenteric fistula, completion cholecystectomy and cystic duct stones. Large scale multicenter prospective studies are required to clarify the role of ICGF in the wide spectrum of CGS.  相似文献   
63.
BackgroundFor patients with melanoma, gastrointestinal immune-related adverse events are common after receipt of anti-CTLA4 therapy. These present difficult decision points regarding whether to discontinue therapy. Detailing the situations in which colitis might predict for improved survival and how this is affected by discontinuation or resumption of therapy can help guide clinical decision-making.Materials and MethodsPatients with stage IV melanoma receiving anti-CTLA4 therapy from 2008 to 2019 were analyzed. Immune-related colitis treated with ≥50 mg prednisone or equivalent daily or secondary immunosuppression was included. Moderate colitis was defined as receipt of oral glucocorticoids only; severe colitis was defined as requiring intravenous glucocorticoids or secondary immunosuppression. The primary outcome was overall survival (OS).ResultsIn total, 171 patients received monotherapy, and 91 received dual checkpoint therapy. In the monotherapy group, 25 patients developed colitis and a nonsignificant trend toward improved OS was observed in this group. Notably, when colitis was categorized as none, moderate or severe, OS was significantly improved for moderate colitis only. This survival difference was not present after dual checkpoint therapy. There were no differences in known prognostic variables between groups, and on multivariable analysis neither completion of all ipilimumab cycles nor resumption of immunotherapy correlated with OS, while the development of moderate colitis did significantly affect OS.ConclusionThis single-institution retrospective series suggests moderate colitis correlates with improved OS for patients with stage IV melanoma treated with single-agent anti-CTLA4, but not dual agent, and that this is true regardless of whether the immune-checkpoint blockade is permanently discontinued.  相似文献   
64.
The present review covers advancement in the area of C–H functionalization on triazole rings, by utilizing various substrates with palladium or copper as catalysts, and resulting in the development of various substituted 1,2,3- and 1,2,4-triazoles. Synthesis of these substituted compounds is necessary from the perspective of pharmaceutical, medicinal, and materials chemistry.

The present review covers advancement in the area of C–H functionalization on triazole rings, by utilizing various substrates with palladium or copper as catalysts, and resulting in the development of various substituted 1,2,3- and 1,2,4-triazoles.  相似文献   
65.
The application of 2-aryl/heteroarylidene-1H-indene-1,3(2H)-dione as an activated olefin source in the DABCO-catalyzed [3 + 2] cycloaddition with N-2,2,2-trifluoroethylisatin ketimines has been disclosed. This highly efficient 1,3-dipolar cycloaddition reaction offered a variety of trifluoro methyl group bearing spiro-pyrrolidine linked oxindoles with four consecutive stereocentres in good to excellent yield and excellent diastereoselectivity. The synthetic practicality of the protocol was established by demonstrating the enantioselective construction of spiro-pyrrolidine-oxindoles with two vicinal spiro-quaternary chiral centres in good yield excellent enantioselectivity (>90% ee) by using ultralow loading of quinine as the catalyst at room temperature.

A highly chemo- and regioselective construction of spiropyrrolidine oxindole is devised via DABCO catalysed [3 + 2] cycloaddition reaction.  相似文献   
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In certain instances, Th17 responses are associated with severe immunopathology. T cell–intrinsic mechanisms that restrict pathogenic effector functions have been described for type 1 and 2 responses but are less well studied for Th17 cells. Here, we report a cell-intrinsic feedback mechanism that controls the pathogenicity of Th17 cells. Th17 cells produce IL-24, which prompts them to secrete IL-10. The IL-10–inducing function of IL-24 is independent of the cell surface receptor of IL-24 on Th17 cells. Rather, IL-24 is recruited to the inner mitochondrial membrane, where it interacts with the NADH dehydrogenase (ubiquinone) 1 α subcomplex subunit 13 (also known as Grim19), a constituent of complex I of the respiratory chain. Together, Grim19 and IL-24 promote the accumulation of STAT3 in the mitochondrial compartment. We propose that IL-24–guided mitochondrial STAT3 constitutes a rheostat to blunt extensive STAT3 deflections in the nucleus, which might then contribute to a robust IL-10 response in Th17 cells and a restriction of immunopathology in experimental autoimmune encephalomyelitis.  相似文献   
69.
Heat shock protein 70 (HSP70) is a predominant member of the HSP family of proteins, which play a variety of functions in the cells and are responsible for cytoprotection under stress conditions. The present study was characterized by HSP70 (orf) in buffalo (Buablus bubalis). Genomic DNA was isolated from lymphocytes and that was used for PCR amplification of HSP70 gene. Polymerase chain reaction product (1,926 bp) was cloned in pGEM-T easy vector and sequenced. Sequence analysis revealed 1,926 bp long open reading frame of HSP70 gene encoding 641 amino acids in buffalo. The amino acid sequence showed 98 % identity with Bos taurus, Bos indicus, Yak, Capra hircus and 90–95 % identity with Camelus dromedaries, Felis catus, Canis familiaris, Sus scrofa, and Homo sapiens. The expression of this gene was in prokaryotic expression vector pPRoExHTa producing a recombinant protein of ~70 kDa, which is detected by SDS-PAGE. The tagged protein purified by Ni-NTA affinity chromatography under denaturing conditions was confirmed by western blotting using Ni-NTA HRP conjugate and 4 chloro-1-naphthol as substrate. Recombinant HSP70 was injected in mice and antiserum contained polyclonal antibody, which was detected by western blot. The recombinant HSP70 protein obtained may be used for the development of an assay for detection of thermal stress.  相似文献   
70.
Purpose:To analyze the incidence of rhegmatogenous retinal detachment (RRD) in patients who have undergone prior Aurolab aqueous drainage implant (AADI) surgery and report outcomes in terms of anatomic, visual acuity, and intraocular pressure (IOP) findings.Methods:Case records of all patients who underwent RRD repair after AADI surgery from 2013 to 2019 were retrospectively analyzed. Data collected included patient demographics, ocular examination findings at all visits including IOP and best-corrected visual acuity (BCVA) and clinical findings related to RRD both at baseline and postoperatively.Results:Ten eyes of nine patients were included in study. The mean age of patients was 28.2 years (median: 15 years, range: 6–83 years). Mean duration between AADI and RRD was 14 months (median 2.5 months; range 2 days-72 months). All eyes underwent pars plana vitrectomy with silicon oil injection. The preoperative LogMAR BCVA (logarithm of the minimum angle of resolution) was 2.52 ± 0.15 which improved to 2.29 ± 0.58 at final follow-up; however, only one eye had vision ≥ 20/400 largely due to recurrent RRD and advanced glaucomatous disc damage. Postoperatively retina was attached in 6 eyes (60%) and IOP was ≤ 21 mmHg in 5 out of 6 eyes with anatomic successConclusion:The incidence of RRD following AADI was found to be 0.86% in our study. Pars plana vitrectomy (PPV) with silicon oil tamponade was the preferred approach in the management of these eyes with IOP being well controlled post PPV. However, visual acuity outcomes were largely unsatisfactory due to recurrent RRD and preexisting advanced glaucoma.  相似文献   
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