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1.
Microvasc Res ; 154: 104682, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38521153

RESUMO

Dysfunctional pericytes and disruption of adherens or tight junctions are related to many microvascular diseases, including diabetic retinopathy. In this context, visualizing retinal vascular architecture becomes essential for understanding retinal vascular disease pathophysiology. Although flat mounts provide a demonstration of the retinal blood vasculature, they often lack a clear view of microaneurysms and capillary architecture. Trypsin and elastase digestion are the two techniques for isolating retinal vasculatures in rats, mice, and other animal models. Our observations in the present study reveal that trypsin digestion impacts the association between pericytes and endothelial cells. In contrast, elastase digestion effectively preserves these features in the blood vessels. Furthermore, trypsin digestion disrupts endothelial adherens and tight junctions that elastase digestion does not. Therefore, elastase digestion emerges as a superior technique for isolating retinal vessels, which can be utilized to collect reliable and consistent data to comprehend the pathophysiology of disorders involving microvascular structures.


Assuntos
Camundongos Endogâmicos C57BL , Elastase Pancreática , Pericitos , Vasos Retinianos , Tripsina , Animais , Elastase Pancreática/metabolismo , Tripsina/metabolismo , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia , Pericitos/metabolismo , Pericitos/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células Endoteliais/enzimologia , Junções Íntimas/metabolismo , Camundongos , Masculino
2.
Bioorg Med Chem Lett ; 109: 129853, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38909705

RESUMO

Overexpression of Bcl-2 protein is a predominant hallmark of disturbed apoptotic pathway in most of the cancers. Herein, chromone-linked thiazolidinediones were designed and synthesized to target Bcl-2 for regulating anti-apoptotic proteins. The study on in vitro cancer cell lines revealed the presence of compounds 8a, 8k, 8l, and 8n, which were found to have good to moderate anti-proliferative activity (with an IC50 concentration less than 10 µM). Among them, 8l depicted the highest cytotoxicity on the A549 cell line with an IC50 of 6.1 ± 0.02 µM. Aberrantly, the compounds displayed less toxicity towards human embryonic kidney HEK cells underlining its selectivity. The DCFDA study revealed a gradual increase in the ROS generation of 8l, followed by its quantification by flow analysis. Similarly, the studies including DAPI, AO/EtBr and Annexin-V binding clearly elucidated the DNA damage, membrane integrity prospects, and insights for early and late apoptotic phases. Markedly, the Bcl-2-FITC anti-body study revealed that compound 8l reduced the expression of anti-apoptotic proteins by 79.1 % compared to the control at 9 µM concentration. In addition, the molecular docking study provided the impending scope of these hybrids, showing promising interaction with the Mcl-1 target (member of the Bcl-2 family) with comparable binding affinities.


Assuntos
Antineoplásicos , Apoptose , Proliferação de Células , Cromonas , Ensaios de Seleção de Medicamentos Antitumorais , Tiazolidinedionas , Humanos , Apoptose/efeitos dos fármacos , Cromonas/farmacologia , Cromonas/química , Cromonas/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Tiazolidinedionas/farmacologia , Tiazolidinedionas/química , Tiazolidinedionas/síntese química , Relação Estrutura-Atividade , Proliferação de Células/efeitos dos fármacos , Estrutura Molecular , Relação Dose-Resposta a Droga , Simulação de Acoplamento Molecular , Células HEK293 , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Linhagem Celular Tumoral
3.
Chem Rev ; 122(16): 13516-13546, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35816287

RESUMO

Since the last century, peptides have gained wide acceptance as drugs, with almost 100 already in the market and a large number in the pipeline. In this context, peptide synthesis has grown massively as a stringent field for pharmaceuticals around the globe. Three methodologies, namely, classical solution peptide synthesis (CSPS), solid-phase peptide synthesis (SPPS), and liquid-phase peptide synthesis (LPPS), have made significant contributions to the field. This review provides a comprehensive and integrated vision of LPPS as the third wave for peptide synthesis. LPPS combines the advantages of CSPS and SPPS, where peptide elongation is carried out in solution and the growing peptide chain is supported on a soluble tag, which confers characteristic properties. LPPS protocols allow the large-scale production of peptides and reduce the use of excess reagents and solvents, thus meeting the principles of green chemistry. In this review, tags associated with LPPS are broadly discussed under the following headings: polydisperse polyethylene glycol (PEG), membrane-enhanced peptide synthesis (MEPS), fluorous technology, ionic liquids (ILs), PolyCarbon, hydrophobic polymers, and group-assisted purification (GAP). It also highlights the signature accomplishments of LPPS tags and the limitations of the same.


Assuntos
Líquidos Iônicos , Peptídeos , Técnicas de Química Sintética , Peptídeos/química , Solventes/química
4.
Int J Mol Sci ; 25(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38892071

RESUMO

Peptides displaying antimicrobial properties are being regarded as useful tools to evade and combat antimicrobial resistance, a major public health challenge. Here we have addressed dendrimers, attractive molecules in pharmaceutical innovation and development displaying broad biological activity. Triazine-based dendrimers were fully synthesized in the solid phase, and their antimicrobial activity and some insights into their mechanisms of action were explored. Triazine is present in a large number of compounds with highly diverse biological targets with broad biological activities and could be an excellent branching unit to accommodate peptides. Our results show that the novel peptide dendrimers synthesized have remarkable antimicrobial activity against Gram-negative bacteria (E. coli and P. aeruginosa) and suggest that they may be useful in neutralizing the effect of efflux machinery on resistance.


Assuntos
Dendrímeros , Escherichia coli , Testes de Sensibilidade Microbiana , Triazinas , Dendrímeros/química , Dendrímeros/síntese química , Dendrímeros/farmacologia , Triazinas/química , Triazinas/farmacologia , Triazinas/síntese química , Escherichia coli/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/síntese química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/síntese química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/síntese química
5.
Int Tinnitus J ; 27(2): 104-112, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38507622

RESUMO

BACKGROUND: Health care providers must be aware of the choices in aural rehabilitation methods and assessment procedures available presently to those with hearing impairment in order to facilitate early identification and intervention and ensure quality of care to those hearing impaired individuals. The referrals from the medical fraternities for the audiological services are not uniform across India. Part of reason may be that awareness about the roles of and responsibilities of audiologist's is poor among medical practitioners. In some regions of India medical practitioners may be only grossly be aware of audiologists per se. They may not know enough to refer all individuals with hearing or balance disorders for the required audiological services. AIM: To evaluate changes in pre survey and post survey after education intervention specifically planned for medical practitioners in the state of Sikkim, India. Education intervention included awareness about hearing impairment and its assessment and management by audiologists. METHOD: A pre and post survey comparison research design with purposive convenient sampling technique was applied. Participants were medical practitioners working in geographical area of Sikkim at the time of the study. Inspection of demographic data of respondents showed that they were in their age range of 24 and 60 years and with work experience ranging 1-40 years. Participants were invited for an awareness talk which included, information about hearing loss, early identification and early intervention, tests and management of hearing loss in different age groups, need for hearing aids/cochlear implants, auditory training, and the role of an audiologist in the management of hearing loss and ways to prevent hearing loss. A pre and post awareness program responses were collected from all the participants using a customized questionnaire tool. RESULTS: Respondents exhibited, in the pre-survey questionnaire, lack of awareness in many aspects of audiology, including assessing hearing impairment, diagnosing hearing loss, and the role of an audiologist. There was an overall, statistically significant difference in the level of performance on the pre-awareness and post-awareness responses. CONCLUSION: Following an awareness campaign among the medical professionals in Sikkim, there was a considerable change in their level of awareness of hearing impairment, its assessment, and management by audiologists. The reach of the awareness campaign was significant as around 70% of subjects showed significant change in their knowledge and attitude towards hearing impairment, its management.


Assuntos
Surdez , Perda Auditiva , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Siquim , Perda Auditiva/terapia , Perda Auditiva/reabilitação , Audição , Audiologistas , Índia
6.
Bioorg Chem ; 131: 106313, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36516521

RESUMO

In a quest for effective cancer targeted drug therapy, a series of new ß-carboline tethered indole-3-glyoxylamide derivatives, conjoining salient pharmacophoric properties with prominent cytotoxicity, were synthesized. The in vitro cytotoxic ability of the compounds was established, and many of the compounds exhibited remarkable cytotoxicity (IC50 < 10 µM) on human cancer cell lines like HCT116, A549, SK-MEL-28, and MCF7. Precisely, compound 12x expressed the best cytotoxic potential against melanoma cancer cell line (SK-MEL-28) with an IC50 value of 4.37 µM. In addition, cytotoxicity evaluation against normal kidney cell line (NRK52E) entrenched the cytospecificity and selectivity index of 12x. The traditional apoptosis assays advised morphological and nuclear alterations such as apoptotic body formation, condensed/horseshoe-shaped/fragmented nuclei, and generation of ROS. The flow cytometric analysis revealed significant early and slight late-stage induction of apoptosis. The target-based physiochemical assays indicated the ability of compound 12x to bind with DNA and inhibition of Topoisomerase II. Moreover, molecular modeling studies affirm the excellent DNA intercalation potential and stabilized interactions of 12x with DNA base pairs. In silico prediction of physicochemical parameters revealed the promising drug-like properties of the synthesized derivatives.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , DNA/química , Antineoplásicos/química , Carbolinas/farmacologia , Carbolinas/química , Simulação por Computador , DNA Topoisomerases Tipo II/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células , Apoptose , Linhagem Celular Tumoral
7.
Exp Parasitol ; 246: 108475, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36707015

RESUMO

Malaria remains as a global life-threatening disorder due to the emergence of resistance against standard antimalarials. Consequently, there is a serious need to better understand the biology of the malaria parasite in order to determine appropriate targets for new interventions. Calcyclin binding protein (CacyBP) is a multi-functional and multi-ligand protein that is not well characterized in malaria disease. In this study, we have cloned CacyBP from rodent species Plasmodium yoelii nigeriensis and purified the recombinant protein to carry out its detailed molecular, biophysical and immunological characterization. Molecular characterization indicates that PyCacyBP is a ∼27 kDa protein in parasite lysate and exists in monomer and dimer forms. Bioinformatic analysis of CacyBP showed significant sequence and structural similarities between rodent and human malaria parasites. CacyBP is expressed in all blood stages of P. yoelii nigeriensis parasite. In silico studies proposed the immunogenic potential of CacyBP. The rPyCacyBP immunized mice exhibited elevated levels of IgG1, IgG2a, IgG2b and IgG3 in their serum. Notably, cellular immune response in splenocytes from immunized mice showed increased expression of pro-inflammatory cytokines such as IL-12, IFN-γ and TNF-α. This CacyBP exhibited pro-inflammatory immune response in rodent host. These finding revealed that CacyBP may have the potential to boost the host immunity for protection against malaria infection. The present study provides basis for further exploration of the biological function of CacyBP in malaria parasite.


Assuntos
Antimaláricos , Malária , Parasitos , Plasmodium yoelii , Humanos , Animais , Camundongos , Parasitos/metabolismo , Proteína A6 Ligante de Cálcio S100 , Malária/tratamento farmacológico , Antimaláricos/uso terapêutico , Imunidade Celular , Plasmodium yoelii/genética , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/uso terapêutico
8.
J Enzyme Inhib Med Chem ; 38(1): 2276665, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37919954

RESUMO

Structural tailoring of the flavone framework (position 7) via organopalladium-catalyzed C-C bond formation was attempted in this study. The impact of substituents with varied electronic effects (phenyl ring, position 2 of the benzopyran scaffold) on the antitumor properties was also assessed. Resultantly, the efforts yielded a furyl arm bearing benzopyran possessing a 4-fluoro phenyl ring (position 2) (14) that manifested a magnificent antitumor profile against the Ishikawa cell lines mediated through dual inhibition of PARP and tubulin [(IC50 (PARP1) = 74 nM, IC50 (PARP2) = 109 nM) and tubulin (IC50 = 1.4 µM)]. Further investigations confirmed the ability of 14 to induce apoptosis as well as autophagy and cause cell cycle arrest at the G2/M phase. Overall, the outcome of the study culminated in a tractable dual PARP-tubulin inhibitor endowed with an impressive activity profile against endometrial cancer.


Assuntos
Antineoplásicos , Neoplasias do Endométrio , Flavonas , Humanos , Feminino , Moduladores de Tubulina/farmacologia , Moduladores de Tubulina/química , Tubulina (Proteína)/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Antineoplásicos/farmacologia , Antineoplásicos/química , Apoptose , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/patologia , Flavonas/farmacologia , Benzopiranos , Proliferação de Células
9.
Molecules ; 28(14)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37513361

RESUMO

Here, we report the synthesis of disulfide-reducing agents 2-(dibenzylamino) propane-1,3-dithiol (DPDT) and 2-(dibenzylamino)-2-methylpropane-1,3-dithiol (DMPDT) from serinol and methyl serinol, respectively. DPDT was found to show greater stability than DMPDT. Hence, the effectiveness of DPDT as a reducing agent was evaluated in both liquid and solid phases. The reducing capacity of this agent was comparable to that of DTT.

10.
Biogerontology ; 23(6): 699-729, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36261747

RESUMO

Immunological aging is strongly associated with the observable deleterious effects of human aging. Our understanding of the causes, effects, and therapeutics of aging immune cells has long been considered within the sole purview of immunosenescence. However, it is being progressively realized that immunosenescence may not be the only determinant of immunological aging. The cellular senescence-centric theory of aging proposes a more fundamental and specific role of immune cells in regulating senescent cell (SC) burden in aging tissues that has augmented the notion of senescence immunotherapy. Now, in addition, several emerging studies are suggesting that cellular senescence itself may be prevalent in aging immune cells, and that senescent immune cells exhibiting characteristic markers of cellular senescence, similar to non-leucocyte cells, could be among the key drivers of various facets of physiological aging. The present review integrates the current knowledge related to immunosenescence and cellular senescence in immune cells per se, and aims at providing a cohesive overview of these two phenomena and their significance in immunity and aging. We present evidence and rationalize that understanding the extent and impact of cellular senescence in immune cells vis-à-vis immunosenescence is necessary for truly comprehending the notion of an 'aged immune cell'. In addition, we also discuss the emerging significance of dietary factors such as phytochemicals, probiotic bacteria, fatty acids, and micronutrients as possible modulators of immunosenescence and cellular senescence. Evidence and opportunities related to nutritional bioactive components and immunological aging have been deliberated to augment potential nutrition-oriented immunotherapy during aging.


Assuntos
Senescência Celular , Imunossenescência , Humanos , Idoso , Senescência Celular/fisiologia , Envelhecimento/fisiologia , Dieta , Imunoterapia
11.
Inflammopharmacology ; 30(2): 655-666, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35254584

RESUMO

Rheumatoid arthritis (RA), a chronic auto-immune disease, is often result of persistent and misdirectional inflammation and cannot be effectually resolved by single-target selective drugs. Present study attempted to uncover anti-arthritic efficacy and governing molecular mechanism of BLFE and its phytoconstituents berberine and rutin, with focus on dysregulated oxi-inflammation and structural integrity during articular damage using Collagen II-CFA-induced RA mice model. NMR-based phytometabolomic analysis revealed presence of phenolics and alkaloids such as berberine and rutin. BLFE, rutin and berberine remarkably mitigated Collagen II-CFA-induced disease severity index, articular damage, immune cells influx and pannus formation. An effective decrease in levels of TNF-α, IL-6, IL-1ß, IFN-γ, IL-13, IL-17, MMPs, RORγt, Ob-cadherin, Cox-2, iNOS and enhancement in IL-10, IL-4 and IL-5, BMP-6/7 was observed in BLFE, rutin and berberine treatments. Molecular mechanistic analysis demonstrated reduction in expression of p-STAT-1/3, p-PI3K, p-Akt, p-JNK, p-p38, p-IκB, p-NF-κB and ß-catenin via BLFE, rutin and berberine. Furthermore, reduced activation of p-ERK and p-GSK3ß and enhanced splenic Tregs was only noticed in BLFE and berberine. Thus, the signifying presence of these phytoconstituents could contribute to the above-mentioned findings. These findings imply that BLFE could be beneficial for assuaging deleterious aspects of RA mediated via perturbed inflammation.


Assuntos
Artrite Experimental , Berberina , Berberis , Lycium , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Artrite Experimental/induzido quimicamente , Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Berberina/farmacologia , Berberina/uso terapêutico , Colágeno , Modelos Animais de Doenças , Frutas , Glicogênio Sintase Quinase 3 beta , Inflamação/tratamento farmacológico , Lycium/metabolismo , Camundongos , NF-kappa B/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Proteínas Proto-Oncogênicas c-akt , Rutina/farmacologia
12.
Lasers Med Sci ; 36(3): 521-528, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32494979

RESUMO

Transurethral endoscopic incision is an established treatment option for management of obstructing ureterocele. It can be performed using monopolar electrocautery or holmium laser as an energy source. The present study was carried out to evaluate outcomes of transurethral ureterocele incision (TUI) by two different energy sources, i.e., monopolar electrocautery versus holmium laser. A retrospective review of the data of all patients who underwent endoscopic TUI from 2007-2017 was performed. Preoperative clinical, biochemical, and radiological characteristics and operative parameters were reviewed and compared between the two groups. Associated stone in the ureterocele was fragmented using pneumatic lithotripter or Mauermeyer stone punch forceps in the electrocautery group and holmium laser in the laser group. Statistical analysis was performed using IBM SPSS version 21.0. Chi-squared test was used for categorical/dichotomous variables. Unpaired t test was used for continuous variables. Out of total 44 patients, 28 patients had duplex system ureterocele and 16 patients had single system ureterocele. Mean age was 18.5 + 7.4 years (range 14-26 years). Six patients had associated stones in the ureterocele. Most common presentation was flank pain followed by urinary infections and bladder outlet obstruction. Preoperative vesico-ureteric reflux was seen in 18% patients. Monopolar TUI was performed in 20 patients and laser-TUI in 24 patients. Three patients had associated stone in ureterocele in each group. Fragmentation of stone was successfully done with holmium laser without changing the instrument and with less associated surgical morbidity in the laser group. Postoperative successful decompression was evident in 38 (90%) patients. Renal parenchyma thickness was improved on ultrasound scan and renal scan showed non-obstructed system in all patients at follow-up. Both laser and monopolar incision have similar efficacy in decompressing the ureterocele in long-term follow-up. However, laser has added advantage of stone lithotripsy with the same instruments with lesser morbidity and lower incidence of persistent reflux.


Assuntos
Eletrocoagulação , Lasers de Estado Sólido/uso terapêutico , Atenção Terciária à Saúde , Ureterocele/cirurgia , Uretra/cirurgia , Adolescente , Adulto , Eletrocoagulação/efeitos adversos , Feminino , Humanos , Injeções Intravenosas , Rim/diagnóstico por imagem , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia/efeitos adversos , Ureter/diagnóstico por imagem , Ureterocele/complicações , Ureterocele/diagnóstico por imagem , Bexiga Urinária/diagnóstico por imagem , Urografia , Adulto Jovem
13.
Genomics ; 112(2): 1264-1272, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31356968

RESUMO

Fis (Factor for inversion stimulation) and H-NS (Histone-like nucleoid-structuring protein) are two well-known nucleoid-associated proteins (NAPs) in proteobacteria, which play crucial roles in genome organization and transcriptional regulation. We performed RNA-sequencing to identify genes regulated by these NAPs. Study reveals that Fis and H-NS affect expression of 462 and 88 genes respectively in Escherichia coli at mid-exponential growth phase. By integrating available ChIP-seq data, we identified direct and indirect regulons of Fis and H-NS proteins. Functional analysis reveals that Fis controls expression of genes involved in translation, oxidative phosphorylation, sugar metabolism and transport, amino acid metabolism, bacteriocin transport, cell division, two-component system, biofilm formation, pilus organization and lipopolysaccharide biosynthesis pathways. However, H-NS represses expression of genes in cell adhesion, recombination, biofilm formation and lipopolysaccharide biosynthesis pathways under mid-exponential growth condition. The current regulatory networks thus provide a global glimpse of coordinated regulatory roles for these two important NAPs.


Assuntos
Proteínas de Escherichia coli/genética , Fator Proteico para Inversão de Estimulação/genética , Proteínas de Fímbrias/genética , Redes Reguladoras de Genes , Transcriptoma , Escherichia coli , Proteínas de Escherichia coli/metabolismo , Fator Proteico para Inversão de Estimulação/metabolismo , Proteínas de Fímbrias/metabolismo , Regulação Bacteriana da Expressão Gênica , Estudo de Associação Genômica Ampla
14.
Molecules ; 26(4)2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33562072

RESUMO

This review provides an overview of the broad applicability of s-triazine. Our many years working with this intriguing moiety allow us to discuss its wide activity spectrum (inhibition against MAO-A and -B, anticancer/antiproliferative and antimicrobial activity, antibacterial activity against MDR clinical isolates, antileishmanial agent, and use as drug nano delivery system). Most of the compounds addressed in our studies and those performed by other groups contain only N-substitution. Exploiting the concept of orthogonal chemoselectivity, first described by our group, we have successfully incorporated different nucleophiles in different orders into s-triazine core for application in peptides/proteins at a temperature compatible with biological systems.


Assuntos
Descoberta de Drogas , Triazinas/química , Animais , Humanos , Triazinas/metabolismo
15.
Molecules ; 26(4)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671801

RESUMO

Several derivatives containing morpholine/piperidine, anilines, and dipeptides as pending moieties were prepared using s-triazine as a scaffold. These compounds were evaluated for their anticancer activity against two human breast cancer cell lines (MCF-7 and MDA-MB-231), a colon cancer cell line (HCT-116), and a non-tumorigenic cell line (HEK 293). Tamoxifen was used as a reference. Animal toxicity tests were carried out in zebrafish embryos. Most of these compounds showed a higher activity against breast cancer than colon cancer. Compound 3a-which contains morpholine, aniline, and glycylglycinate methyl ester-showed a high level of cytotoxicity against MCF-7 cells with IC50 values of less than 1 µM. This compound showed a much lower level of toxicity against the non-tumorigenic HEK-293 cell line, and in the in vivo studies using zebrafish embryos. Furthermore, it induced cell cycle arrest at the G2/M phase, and apoptosis in MCF-7 cells. On the basis of our results, 3a emerges as a potential candidate for further development as a therapeutic drug to treat hormone receptor-positive breast cancer.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Dipeptídeos/farmacologia , Triazinas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dipeptídeos/síntese química , Dipeptídeos/química , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Triazinas/síntese química , Triazinas/química , Peixe-Zebra/embriologia
16.
Educ Inf Technol (Dordr) ; 26(6): 7015-7032, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33935576

RESUMO

The COVID-19 pandemic has struck education system around the globe. The pandemic initiated an immediate and complete lockdown of all the educational institutions, to keep social distancing. According to healthcare professionals, lockdown and social distancing could help to flatten the infection curve and reduce total fatalities from the COVID-19 pandemic. It has affected more than 90% of the world's learners, as the regular learning approaches are not appropriate in this out of the ordinary times and online learning seems to have become a critical salvation for learning, the educational institutions attempt to minimize the community spread of the disease. All the people participating in the education system accepted that teaching and learning methods need to be altered in the period of COVID-19 as the situation led to forced adaptation of e-learning methods. This paper investigates and evaluates the learners' perception in a higher education institution of India and compares the difference in the perception of the same students in Pre and Post COVID 19 period, using the Statistical Package for Social Sciences program (SPSS) version 23.0 and JASP 0.14.1 software applications for descriptive and analytical statistics i.e. medium, minimum, maximum, paired t-test and correlation. The result of this papers confirmed that there exists a statistically significant difference in the students' perception towards the Pre-Pandemic and Post-Pandemic learning methods, which indicates that students have a higher perception of the Pre-Pandemic learning blended learning, than that of the Post Pandemic learning web-assisted learning.

17.
Chembiochem ; 21(14): 1947-1954, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32196882

RESUMO

Cysteine is present in a large number of natural and synthetic (bio)molecules. Although the thiol side chain of Cys can be in a free form, in most cases it forms a disulfide bond either with a second Cys (bridge) or with another thiol, as in the case of protecting groups. Efficient reduction of these disulfide bridges is a requirement for many applications of Cys-containing molecules in the fields of chemistry and biochemistry. Here we review reducing methods for disulfide bonds, taking into consideration the solubility of the substrates when selecting the appropriate reducing reagent.


Assuntos
Dissulfetos/química , Substâncias Redutoras/química , Humanos , Estrutura Molecular , Solubilidade
18.
Biogerontology ; 21(3): 325-343, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32043170

RESUMO

The present study aimed at evaluating the role of senescent cell microenvironment as an extrinsic causal factor for altered age-associated macrophage functions, and that whether such changes could be ameliorated by the application of tea catechin epigallocatechin gallate (EGCG). To ascertain this, we analyzed the impact of secretory metabolites of proliferating (P) and senescent (S) preadipocyte cells on the induction of phenotypic and functional characteristics associated with aging in macrophages isolated from young (YM) and old (OM) C57BL/6J mice. The role of EGCG as alleviator of preadipocyte media-induced senescence and inflamm-aging was evaluated in OM. Results revealed strong age-related dysregulation in macrophage functions as evident by decreased CD11b expression, enhanced expression of cytokines (IL-6/TNF-α/IL-1ß/IL-10) and cell cycle inhibitors p53/p21WAF1/p16Ink4a, as well as augmentation of M2 phenotype (Arg1/Msr1/Mrc1) and SA-ß-gal activity. Ex vivo exposure of macrophages (YM and OM) to secretory factors of preadipocytes induced differential effects, and treatment with S culture media largely showed an augmentation of senescent phenotype, particularly in the YM. Pretreatment with EGCG (10 µM) to OM caused a dramatic reversal of both age-associated and preadipocyte media-induced changes as evident from upregulation of CD11b and ROS levels, inhibition of inflammatory makers, attenuation of p53/p21WAF1/p16Ink4a expression and SA-ß-gal activity. Our results indicate vital role of adipose tissue-mediated extrinsic factors in shaping macrophage phenotype and functions during aging. It is also apparent that EGCG is a promising candidate in developing preventive therapies aimed at alleviating macrophage inflamm-aging and senescence that may help curb incidences of inflammatory disorders in elderly.


Assuntos
Envelhecimento , Catequina/análogos & derivados , Macrófagos , Animais , Catequina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Compostos Fitoquímicos
19.
Eur J Nutr ; 59(6): 2663-2681, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31620885

RESUMO

PURPOSE: There is a growing interest in developing phytomolecule-based therapies for the management of inflammatory disorders owing to rising cost of treatments and unwarranted effects. The present work attempted to assess the efficacy and mechanisms of Berberis lycium Royle fruit extract (BLFE) in mitigating chemical-induced colitis in mice. METHODS: Colitis was induced in Balb/C mice using dextran sulphate sodium (DSS) and protective effects of BLFE were examined. Several oxi-inflammatory parameters, histopathological changes, epithelial barrier integrity and activation of NF-κB/c-Jun/MAPKs in colon tissue were determined. Splenic T cell subpopulations were also gauged to evaluate the systemic effects of BLFE in the modulation of immune responses. RESULTS: BLFE treatment effectively improved animal survival rate, DAI score, colon length and structural damage in DSS-exposed mice. Expression of oxi-inflammatory markers such as MPO, IgE, iNOS, ICAM-1, MCP-1 and RANTES as well as Th1/Th2/Th17 cytokines were decreased in BLFE treated animals. On the other hand, an increased mRNA expression of anti-inflammatory cytokines (IL-4/IL-10), tight junction proteins and IgA levels were also observed during BLFE treatment. BLFE appeared to modulate intestinal epithelial cell proliferation (PCNA) and apoptosis (Bcl2/Bax), thereby suggesting its role in the maintenance of intestinal integrity. Analysis of inflammatory signalling pathways indicated robust activation and expression of NF-κB/c-Jun/MAPKs (JNK and p38) in DSS treated animal which was strongly abrogated by BLFE treatment. BLFE supplementation also enhanced the proliferation of CD3+CD4+CD25+ Treg cells indicating suppression of inflammatory activation. CONCLUSION: These observations provide compelling evidence that BLFE could be considered as a viable natural strategy in the prevention and management of ulcerative colitis.


Assuntos
Berberis , Colite Ulcerativa , Colite , Lycium , Animais , Proliferação de Células , Colo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Frutas , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/genética , Extratos Vegetais/farmacologia , Linfócitos T Reguladores
20.
Bioorg Chem ; 104: 104334, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33142409

RESUMO

In the field of bioconjugation, linker development has witnessed massive growth in recent years. 2,4,6-Trichloro-1,3,5-triazine (TCT) is a tridentate linker that can accommodate three distinct nucleophiles. Herein, the reaction of azido triazine derivatives with nucleophiles (amine, thiol and phenol) is studied. The replacement of first chlorine was performed at 0 °C while that of the last chlorine was achieved successfully at rt. As a proof of concept of this strategy with potential application in biological studies, pentapeptides (Ac-XGGFL-NH2 where X = Lys or Tyr or Cys) were reacted with 2-azido-4,6-dichlorotriazine to replace the first and second chlorine at 0 °C and at rt, respectively. The reactivity of 2-azido-4,6-dichlorotriazine was found to be similar for the α and ε amine group present in same peptide. These findings demonstrate the applicability of 2-azido-4,6-dichlorotriazine as a linker with potential further application in bioconjugation.


Assuntos
Azidas/química , Nitrogênio/química , Oxigênio/química , Peptídeos/química , Enxofre/química , Triazinas/química , Estrutura Molecular , Estereoisomerismo
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