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1.
Tissue Cell ; 80: 101969, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36403499

RESUMO

Extracellular matrices (ECM) present in our tissues play a significant role in maintaining tissue homeostasis through various physical and chemical cues such as topology, stiffness, and secretion of biochemicals. They are known to influence the behavior of resident stem cells. It is also known that ECM type and coating density on cell culture plates strongly influence in vitro cellular behavior. However, the influence of ECM protein coating on long-term mesenchymal stem cell expansion has not been studied yet. To address this gap, we cultured bone-marrow derived hMSCs for multiple passages on the tissue culture plastic plates coated with 25 µg/ml of various ECM proteins. We found that cells on plates coated with ECM proteins had much higher proliferation compared to the regular tissue culture plates. Further, gelatin-coated plates helped the cells to grow faster compared to collagen, fibronectin, and laminin coated plates. Additionally, the use of gelatin showed less size heterogeneity among the cells when expanded from passages 3 to 9 (P3 to P9). Gelatin also helped in maintaining cellular stiffness which was not observed across other ECM proteins. In summary, in this research, we have shown that gelatin which is the least expensive compared to other ECM proteins, provides a better platform for mesenchymal stem cell expansion.


Assuntos
Proteínas da Matriz Extracelular , Células-Tronco Mesenquimais , Proteínas da Matriz Extracelular/metabolismo , Gelatina/metabolismo , Matriz Extracelular/metabolismo , Técnicas de Cultura de Células , Proliferação de Células , Células Cultivadas , Diferenciação Celular
2.
Cancer Discov ; 12(2): 450-467, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34531253

RESUMO

An enhanced requirement for nutrients is a hallmark property of cancer cells. Here, we optimized an in vivo genetic screening strategy in acute myeloid leukemia (AML), which led to the identification of the myo-inositol transporter SLC5A3 as a dependency in this disease. We demonstrate that SLC5A3 is essential to support a myo-inositol auxotrophy in AML. The commonality among SLC5A3-dependent AML lines is the transcriptional silencing of ISYNA1, which encodes the rate-limiting enzyme for myo-inositol biosynthesis, inositol-3-phosphate synthase 1. We use gain- and loss-of-function experiments to reveal a synthetic lethal genetic interaction between ISYNA1 and SLC5A3 in AML, which function redundantly to sustain intracellular myo-inositol. Transcriptional silencing and DNA hypermethylation of ISYNA1 occur in a recurrent manner in human AML patient samples, in association with IDH1/IDH2 and CEBPA mutations. Our findings reveal myo-inositol as a nutrient dependency in AML caused by the aberrant silencing of a biosynthetic enzyme. SIGNIFICANCE: We show how epigenetic silencing can provoke a nutrient dependency in AML by exploiting a synthetic lethality relationship between biosynthesis and transport of myo-inositol. Blocking the function of this solute carrier may have therapeutic potential in an epigenetically defined subset of AML.This article is highlighted in the In This Issue feature, p. 275.


Assuntos
Proteínas de Choque Térmico/genética , Inositol/biossíntese , Leucemia Mieloide Aguda/tratamento farmacológico , Simportadores/genética , Animais , Biologia do Desenvolvimento , Humanos , Camundongos
3.
Asian J Neurosurg ; 16(1): 183-186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34211891

RESUMO

Astroblastoma is a very rare glial tumor derived from astroblasts. It has been controversial in terms of its features and diagnosis. The objective of this report is to present the findings of the high-grade astroblastoma with a good prognosis in a 21-year-old female who presented to us with diplopia and headache. While imaging led to the foremost differentials of pleomorphic xanthoastrocytoma and Ganglioglioma which are low-grade neoplasms, the final diagnosis was established on microscopy and immunohistochemistry after excision. Treatment protocol included surgery with postoperative radiotherapy and chemotherapy. Due to controversial and limited literature, this tumor poses difficulties in diagnosis and management. This is a rare, successfully managed case of astroblastoma with a positive outcome 5 years after the diagnosis was established. In this case report, we review the steps of diagnosis, the differentials, the pathological and histological features, and the management of this rare entity.

4.
Cancer Discov ; 11(9): 2300-2315, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33893150

RESUMO

Hundreds of genes become aberrantly silenced in acute myeloid leukemia (AML), with most of these epigenetic changes being of unknown functional consequence. Here, we demonstrate how gene silencing can lead to an acquired dependency on the DNA repair machinery in AML. We make this observation by profiling the essentiality of the ubiquitination machinery in cancer cell lines using domain-focused CRISPR screening, which revealed Fanconi anemia (FA) proteins UBE2T and FANCL as unique dependencies in AML. We demonstrate that these dependencies are due to a synthetic lethal interaction between FA proteins and aldehyde dehydrogenase 2 (ALDH2), which function in parallel pathways to counteract the genotoxicity of endogenous aldehydes. We show DNA hypermethylation and silencing of ALDH2 occur in a recurrent manner in human AML, which is sufficient to confer FA pathway dependency. Our study suggests that targeting of the ubiquitination reaction catalyzed by FA proteins can eliminate ALDH2-deficient AML. SIGNIFICANCE: Aberrant gene silencing is an epigenetic hallmark of human cancer, but the functional consequences of this process are largely unknown. In this study, we show how an epigenetic alteration leads to an actionable dependency on a DNA repair pathway through the disabling of genetic redundancy.This article is highlighted in the In This Issue feature, p. 2113.


Assuntos
Aldeído-Desidrogenase Mitocondrial/genética , Proteínas de Grupos de Complementação da Anemia de Fanconi/metabolismo , Leucemia Mieloide Aguda/genética , Linhagem Celular Tumoral , Humanos , Ubiquitinação
5.
Cureus ; 13(1): e12926, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33654608

RESUMO

Background and objectives Eating disorders are some of the most under-researched and difficult to diagnose psychiatric conditions, with a high mortality rate, especially among the adolescent age group. The aim of this study is to determine the prevalence and risk factors for eating disorders among students of a medical college hospital in South India. Materials and methods An observational, cross-sectional study was conducted among 332 students of four constituent colleges of a tertiary-care hospital selected by simple random sampling. Their height and weight were recorded. Four major questionnaires were distributed among the students - Demographic details, Eating Attitudes Test (EAT26), Body Shape Questionnaire (BSQ34), and Perceived Stress Scale (PSS). The results were tabulated and analyzed using SPSS software version 16.0 (IBM Corporation, Somers, New York, USA). Results The proportion of students who had a high risk for eating disorders was 13%. It was prevalent almost equally in both males and females. High risk for eating disorders was associated with high stress and severe body shape concerns (p<0.001). Other influencing factors were history of counselling, peer pressure, excessive exercise as well as the history of any behavioral symptoms like the use of laxatives and diet pills (p<0.001). Conclusions Eating disorder risk is prevalent in a high percentage of medical and paramedical students. High stress and body shape concerns are associated with eating disorders. Only if diagnosed early, with screening programs using questionnaires and further psychiatric evaluation, we can hope to mitigate the complications they incur.

6.
Open Med (Wars) ; 15(1): 1137-1142, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33336069

RESUMO

Rapunzel syndrome, defined by the presence of a trichobezoar extending from the stomach to the small intestine, is a rare cause of intestinal obstruction. It usually presents with vague symptoms; however, it can also present with complications such as perforation, peritonitis and obstructive jaundice. We report a rare case of a 37-year-old woman with Rapunzel syndrome complicated by acute cholangitis and pancreatitis and analyse the diagnosis and management of this complicated pathology. Although she reported a history of trichotillomania and trichophagia, she had been asymptomatic for ten years. We review the steps of diagnosis, highlighting the importance of a thorough clinical history and detailed examination, with supporting evidence from the contrast-enhanced computed tomography (CECT) scan. She was successfully managed with gastrotomy and trichobezoar removal. She had an uneventful postoperative recovery and was discharged after psychiatric counselling. To our knowledge, this is the first case of Rapunzel syndrome in a young female presenting with both cholangitis and pancreatitis.

7.
ACS Omega ; 5(22): 13333-13343, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32548520

RESUMO

In a new and environmentally sustainable approach, a series of 2-arylimidazo[1,2-a]pyridine derivatives were synthesized in aqueous media in the presence of iodine as a catalyst. The reaction proceeded by condensation of various aryl methyl ketones with 2-aminopyridines to afford 2-arylimidazo[1,2-a]pyridines in good overall yields. Although several of the reactions were efficiently performed "on water", the addition of a surfactant, namely, sodium dodecyl sulphate , was found effective in terms of substrate scope and yield enhancement. Both methods were successfully used for the gram-scale synthesis of a marketed drug, zolimidine. The simple experimental setup, water as "green" media, and inexpensive catalyst are some of the merits of this protocol.

8.
Sci Rep ; 10(1): 7428, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32366893

RESUMO

Lithium is an effective, well-established treatment for bipolar disorder (BD). However, the mechanisms of its action, and reasons for variations in clinical response, are unclear. We used neural precursor cells (NPCs) and lymphoblastoid cell lines (LCLs), from BD patients characterized for clinical response to lithium (using the "Alda scale" and "NIMH Retrospective Life chart method"), to interrogate cellular phenotypes related to both disease and clinical lithium response. NPCs from two biologically related BD patients who differed in their clinical response to lithium were compared with healthy controls. RNA-Seq and analysis, mitochondrial membrane potential (MMP), cell viability, and cell proliferation parameters were assessed, with and without in vitro lithium. These parameters were also examined in LCLs from 25 BD patients (16 lithium responders and 9 non-responders), and 12 controls. MMP was lower in both NPCs and LCLs from BD; but it was reversed with in vitro lithium only in LCLs, and this was unrelated to clinical lithium response. The higher cell proliferation observed in BD was unaffected by in vitro lithium. Cell death was greater in BD. However, LCLs from clinical lithium responders could be rescued by addition of in vitro lithium. In vitro lithium also enhanced BCL2 and GSK3B expression in these cells. Our findings indicate cellular phenotypes related to the disease (MMP, cell proliferation) in both NPCs and LCLs; and those related to clinical lithium response (cell viability, BCL2/GSK3B expression) in LCLs.


Assuntos
Transtorno Bipolar/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Lítio/uso terapêutico , Adulto , Antimaníacos/uso terapêutico , Ciclo Celular , Linhagem Celular/efeitos dos fármacos , Proliferação de Células , Avaliação Pré-Clínica de Medicamentos , Feminino , Perfilação da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Masculino , Potencial da Membrana Mitocondrial , Pessoa de Meia-Idade , Fenótipo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA-Seq , Estudos Retrospectivos
9.
Artigo em Inglês | MEDLINE | ID: mdl-31730529

RESUMO

Background The Global Status Report 2017 reveals that 11% of Indians indulge in binge drinking. Chronic alcohol intake may lead to cardiac problems and hypertension. The aim of this study was to evaluate cardiovascular risk among asymptomatic chronic alcoholics. Methods A total of 80 asymptomatic chronic alcoholics of South Indian origin, from the psychiatry ward of Sri Ramachandra Institute of Higher Education and Research, India were diagnosed with alcohol dependence syndrome(ADS). Group I includes alcoholics for 10 years or less and group II includes alcoholics for more than 10 years. Alcohol consumption was measured using the DSM IV criteria. Blood pressure (BP) and electrocardiographic (ECG) data were measured on admission and 2 weeks later. The paired t-test compared a significant outcome of the two sets of data at p ≤ 0.05 level of significance. Results Forty percent of the patients were found to be hypertensive and only 2.5% were found to be pre-hypertensive on admission. The mean age of the hypertensives was 46.9 and nonhypertensives was 42.1 The difference in the BP evaluated after 2 weeks was staggering - systolic BP had a mean fall of 6.1 mm Hg (p < 0.001) and diastolic BP 2.25 mm Hg (p = 0.001). The electrocardiogram results showed significant changes like left ventricular hypertrophy, abnormal T waves, and QT prolongation. Conclusions Chronic alcoholism is a major criterion for heart abnormalities such as elevated BP and left ventricular enlargement, and our study supports this as we see that alcohol consumption for more than 10 years shows significant deterioration. Further clinical observations and long-term prospective studies are needed to confirm these observations.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Alcoolismo/complicações , Pressão Sanguínea/efeitos dos fármacos , Eletrocardiografia/efeitos adversos , Coração/efeitos dos fármacos , Adulto , Alcoólicos , Eletrocardiografia/efeitos dos fármacos , Feminino , Humanos , Hipertensão/induzido quimicamente , Índia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
10.
ACS Omega ; 3(6): 5958-5970, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30023935

RESUMO

Hispolon (HS), a bioactive polyphenol, and its derivatives such as hispolon monomethyl ether (HME), hispolon pyrazole (HP), and hispolon monomethyl ether pyrazole (HMEP) were evaluated for comparative toxicity and antigenotoxic effects. The stability of HS derivatives in biological matrices followed the order HS < HP ≈ HME < HMEP. The cytotoxicity analysis of HS derivatives indicated that HP and HMEP were less toxic than HS and HME, respectively, in both normal and tumor cell types. The mechanisms of toxicity of HS and HME involved inhibition of thioredoxin reductase (TrxR) and/or induction of reductive stress. From the enzyme kinetic and docking studies, it was established that HS and HME interacted with the NADPH-binding domain of TrxR through electrostatic and hydrophobic bonds, resulting in inhibition of the catalytic activity. Subsequently, treatment with HS, HP, and HMEP at a nontoxic concentration of 10 µM in Chinese Hamster Ovary (CHO) cells showed significant protection against radiation (4 Gy)-induced DNA damage as assessed by micronuclei and γ-H2AX assays. In conclusion, the above results suggested the importance of phenolic and diketo groups in controlling the stability and toxicity of HS derivatives. The pyrazole derivatives, HP and HMEP, may gain significance in the development of functional foods.

11.
Stem Cell Res ; 30: 38-42, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29778976

RESUMO

Human induced Pluripotent Stem Cells (HiPSCs) have immense potential in research and therapeutics. Under the aegis of Department of Biotechnology funded national program entitled, "The Accelerator program for Discovery in Brain Disorders using Stem Cells (ADBS)" we have established a HiPSC biorepository (https://www.ncbs.res.in/adbs/bio-repository) with an objective to study severe mental illness. The repository comprises of HiPSC lines derived from healthy control donors and individuals with life time diagnosis of severe mental illness from dense families. In the current report we submit information regarding two population control reference lines (male = 1; female = 1) from this biorepository.


Assuntos
Células-Tronco Pluripotentes Induzidas/metabolismo , Diferenciação Celular , Humanos , Índia
12.
Artigo em Inglês | MEDLINE | ID: mdl-25566891

RESUMO

BACKGROUND: Xeroderma pigmentosum (XP) is an autosomal recessive genetic disorder characterized by cutaneous and ocular photosensitivity and an increased risk of developing cutaneous neoplasms. Progressive neurological abnormalities develop in a quarter of XP patients. AIM: To study the clinical profile and perform a mutation analysis in Indian patients with xeroderma pigmentosum. METHODS: Ten families with 13 patients with XP were referred to our clinic over 2 years. The genes XPA, XPB and XPC were sequentially analyzed till a pathogenic mutation was identified. RESULTS: Homozygous mutations in the XPA gene were seen in patients with moderate to severe mental retardation (6/10 families) but not in those without neurological features. Two unrelated families with a common family name and belonging to the same community from Maharashtra were found to have an identical mutation in the XPA gene, namely c.335_338delTTATinsCATAAGAAA (p.F112SfsX2). Testing of the XPC gene in two families with four affected children led to the identification of the novel mutations c.1243C>T or p.R415X and c.1677C>A or p.Y559X. In two families, mutations could not be identified in XPA, XPB and XPC genes. LIMITATION: The sample size is small. CONCLUSION: Indian patients who have neurological abnormalities associated with XP should be screened for mutations in the XPA gene.


Assuntos
DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Deficiência Intelectual/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética , Xeroderma Pigmentoso/genética , Adulto , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Homozigoto , Humanos , Índia , Masculino , Xeroderma Pigmentoso/complicações
13.
Elife ; 3: e01267, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-25117540

RESUMO

The mechanisms generating epileptic neuronal networks following insults such as severe seizures are unknown. We have previously shown that interfering with the function of the neuron-restrictive silencer factor (NRSF/REST), an important transcription factor that influences neuronal phenotype, attenuated development of this disorder. In this study, we found that epilepsy-provoking seizures increased the low NRSF levels in mature hippocampus several fold yet surprisingly, provoked repression of only a subset (∼10%) of potential NRSF target genes. Accordingly, the repressed gene-set was rescued when NRSF binding to chromatin was blocked. Unexpectedly, genes selectively repressed by NRSF had mid-range binding frequencies to the repressor, a property that rendered them sensitive to moderate fluctuations of NRSF levels. Genes selectively regulated by NRSF during epileptogenesis coded for ion channels, receptors, and other crucial contributors to neuronal function. Thus, dynamic, selective regulation of NRSF target genes may play a role in influencing neuronal properties in pathological and physiological contexts.


Assuntos
Regulação da Expressão Gênica , Proteínas do Tecido Nervoso/genética , RNA Mensageiro/genética , Proteínas Repressoras/genética , Convulsões/genética , Transcrição Gênica , Animais , Transporte Biológico , Cromatina/química , Cromatina/metabolismo , Perfilação da Expressão Gênica , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Masculino , Microtomia , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Neurônios/patologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Repressoras/metabolismo , Convulsões/metabolismo , Convulsões/fisiopatologia , Transdução de Sinais , Técnicas de Cultura de Tecidos
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