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1.
Int J Mol Sci ; 24(4)2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36834657

RESUMEN

The pathophysiology of nonalcoholic steatohepatitis (NASH) is complex, owing to its diverse pathological drivers and, until recently, there were no approved drugs for this disease. Tecomella is a popular herbal medicine used to treat hepatosplenomegaly, hepatitis, and obesity. However, the potential role of Tecomella undulata in NASH has not yet been scientifically investigated. The administration of Tecomella undulata via oral gavage lowered body weight, insulin resistance, alanine transaminase (ALT), aspartate transaminase (AST), triglycerides, and total cholesterol in western diet sugar water (WDSW) fed mice but had no effect on chow diet normal water (CDNW) fed mice. Tecomella undulata improved steatosis, lobular inflammation, and hepatocyte ballooning and resolved NASH in WDSW mice. Furthermore, Tecomella undulata also alleviated the WDSW-induced Endoplasmic Reticulum stress and oxidative stress, enhanced antioxidant status, and thus reduced inflammation in the treated mice. Of note, these effects were comparable to saroglitazar, the approved drug used to treat human NASH and the positive control used in the study. Thus, our findings indicate the potential of Tecomella undulata to ameliorate WDSW-induced steatohepatitis, and these preclinical data provide a strong rationale for assessing Tecomella undulata for the treatment of NASH.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Humanos , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/patología , Hígado/patología , Hepatomegalia , Obesidad/patología , Inflamación/patología , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad
2.
Artículo en Inglés | MEDLINE | ID: mdl-37150890

RESUMEN

The mismanagement of consumer-discarded plastic waste (CDPW) has raised global environmental concerns about climate change. The COVID-19 outbreak has generated ∼1.6 million tons of plastic waste per day in the form of personal protective equipment (masks, gloves, face shields, and sanitizer bottles). These plastic wastes are either combustible or openly dumped in aquatic and terrestrial environments. Open dumping upsurges emerging contaminants like micro-nano plastics (MNPs) that directly enter the ecosystem and cause severe impacts on flora and fauna. Therefore, it has become an utmost priority to determine sustainable technologies that can degrade or treat MNPs from the environment. The present review assesses the sources and impacts of MNPs, various challenges, and issues associated with their remediation techniques. Accordingly, a novel sustainable circular model is recommended to increase the degradation efficiency of MNPs using biochemical and biological methods. It is also concluded that the proposed model does not only overcome environmental issues but also provides a sustainable secondary resource to meet the sustainable development goals (SDGs).


Asunto(s)
COVID-19 , Plásticos , Humanos , Microplásticos , Ecosistema , COVID-19/epidemiología , COVID-19/prevención & control
3.
J Environ Manage ; 319: 115727, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35868187

RESUMEN

The incessant population has increased the production and consumption of plastics, paper, metals, and organic materials, which are discarded as solid waste after their end of life. The accumulation of these wastes has created growing concerns all over the world. However, conventional methods of solid waste management i.e., direct combustion and landfilling have caused several negative impacts on the environment (releasing toxic chemicals and greenhouse gases, huge land use) besides affecting human health. Therefore, it is requisite to determine sustainable alternative technologies that not only help in mitigating environmental issues but also increase the economic value of the discarded solid wastes. This process is known as urban mining where waste is converted into secondary resources and thereby conserves the natural primary resources. Thus, this review highlights the technological advancements in the valorization process of discarded wastes and their sustainable utilization. We also discussed several limitations of the existing urban mining processes and further the feasibility of valorization techniques was critically analyzed from a techno-economical perspective. This paper recommends a novel sustainable model based on the circular economy concept, where waste is urban mined and recovered as a secondary resource to support the united nations sustainable development goals (SDGs). The implementation of this model will ultimately help the developing countries to achieve the target of SDGs 11, 12, and 14.


Asunto(s)
Residuos Sólidos , Administración de Residuos , Humanos , Metales , Minería , Plásticos , Residuos Sólidos/análisis , Administración de Residuos/métodos
4.
Ann Diagn Pathol ; 46: 151523, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32325422

RESUMEN

BACKGROUND: Focal cortical dysplasia (FCD) is a localized cortical malformation and considerable morphological overlap exists between FCD IIB and neurological lesions associated with Tuberous sclerosis complex (TSC). Abnormal mTOR pathway secondary to somatic mTOR mutation and TSC gene mutation linked to PI3K/AKT/mTOR pathway have supported the hypothesis of common pathogenesis involved. Role of converging pathway, viz. Wnt/ß-Catenin and mTOR is unknown in FCD. We aimed to analyse FCD IIB for TSC1/TSC2 mutations, immunoreactivity of hamartin, tuberin, mTOR and Wnt signalling cascades, and stem cell markers. MATERIALS AND METHODS: Sixteen FCD IIB cases were retrieved along with 16 FCD IIA cases for comparison. Immunohistochemistry was performed for tuberin, hamartin, mTOR pathway markers, markers of stem cell phenotype, and Wnt pathway markers. Mutation analysis for TSC1 and TSC2 was performed by sequencing in 9 FCD cases. RESULTS: All FCD cases showed preserved hamartin and tuberin immunoreactivity. Aberrant immunoreactivity of phospho-P70S6 kinase, S6 ribosomal, phospho-S6 ribosomal and Stat3 was noted in FCD IIB, with variable phospho-4E-BP1 (45%) and absent phospho-Stat3 expression. Immunoreactivity for phospho-P70S6 kinase (100%), S6 ribosomal protein (100%) and Stat3 (100%) was noted in FCD IIA, but not for phospho-S6 ribosomal, phospho-4E-BP1 and phospho-Stat3. c-Myc immunoreactivity was noted in all FCD cases. Nestin (81%) and Sox 2 (88%) stained balloon cells in FCD IIB (44%), while in FCD IIA cases were negative. All FCD cases were immunopositive for Wnt, but were negative for ß-Catenin and cyclin-D1. TSC mutations were detected in two cases of FCD IIB. CONCLUSION: Abnormal mTOR pathway activation exists in FCD IIB and IIA, however, shows differential immunoreactivity profile, indicating varying degrees of dysregulation. Labelling of neuronal stem cell markers in balloon cells suggests they are phenotypically immature. TSC1/2 mutation play role in the pathogenesis of FCD. Deep targeted sequencing is preferred diagnostic technique since conventional sanger sequencing often fails to detect low-allele frequency variants involved in mTOR/TSC pathway genes, commonly found in FCD.


Asunto(s)
Epilepsia/metabolismo , Epilepsia/patología , Malformaciones del Desarrollo Cortical de Grupo I/metabolismo , Malformaciones del Desarrollo Cortical de Grupo I/patología , Transducción de Señal/fisiología , Serina-Treonina Quinasas TOR/metabolismo , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Adulto Joven
5.
J Neurooncol ; 143(3): 393-403, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31104222

RESUMEN

INTRODUCTION: Molecular classification of medulloblastomas (MB) is prognostically and therapeutically relevant and helps in better risk-stratification. Translation of this subgrouping to routine practice still remains a challenge. The most pathologist accessible techniques for molecular subgrouping include immunohistochemistry (IHC), fluorescent in-situ hybridization (FISH) and NanoString. OBJECTIVES: (1) Molecular subgrouping of MBs by IHC and FISH, and NanoString assay (2) To compare their efficacy and cost for applicability in resource constrained centers. METHODS: Ninety-five cases of MB with adequate tissue were included. Molecular subgrouping was performed by IHC for ß-catenin, GAB1 and YAP1; FISH for MYC amplification, and sequencing for CTNNB1, and by NanoString Assay on the same set of MBs. A subset of cases was subjected to 850k DNA methylation array. RESULTS: IHC + FISH classified MBs into 15.8% WNT, 16.8% SHH, and 67.4% non-WNT/non-SHH subgroups; with MYC amplification identified in 20.3% cases of non-WNT/non-SHH. NanoString successfully classified 91.6% MBs into 25.3% WNT, 17.2% SHH, 23% Group 3 and 34.5% Group 4. However, NanoString assay failure was seen in eight cases, all of which were > 8-years-old formalin-fixed paraffin-embedded tissue blocks. Concordant subgroup assignment was noted in 88.5% cases, while subgroup switching was seen in 11.5% cases. Both methods showed prognostic correlation. Methylation profiling performed on discordant cases revealed 1 out of 4 extra WNT identified by NanoString to be WNT, others aligned with IHC subgroups; extra SHH by NanoString turned out to be SHH by methylation. CONCLUSIONS: Both IHC supplemented by FISH and NanoString are robust methods for molecular subgrouping, albeit with few disadvantages. IHC cannot differentiate between Groups 3 and 4, while NanoString cannot classify older-archived tumors, and is not available at most centres. Thus, both the methods complement each other and can be used in concert for high confidence allotment of molecular subgroups in clinical practice.


Asunto(s)
Neoplasias Cerebelosas/clasificación , Inmunohistoquímica/métodos , Hibridación Fluorescente in Situ/métodos , Meduloblastoma/clasificación , Nanotecnología/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Adolescente , Adulto , Anciano , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias Cerebelosas/genética , Neoplasias Cerebelosas/metabolismo , Neoplasias Cerebelosas/patología , Niño , Preescolar , Estudios de Cohortes , Terapia Combinada , Metilación de ADN , Femenino , Estudios de Seguimiento , Recursos en Salud , Humanos , Lactante , Masculino , Meduloblastoma/genética , Meduloblastoma/metabolismo , Meduloblastoma/patología , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia , Adulto Joven
6.
J Environ Manage ; 248: 109238, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31319199

RESUMEN

Open dumping is a common practice for MSW disposal in most of the Indian cities, apart from the metro-cities. This practice poses significant environmental and health risks due to toxic and greenhouse gases (GHGs) emission through direct combustion and/or decay of wastes. Therefore, integrated solid waste management (ISWM) using different methods viz., incineration, composting, anaerobic digestions, refuse derived fuel, material recovery facility and sanitary landfilling, is much needed. Accordingly, three waste management case scenarios were studied for year 2001-2051 by keeping weightage of sustainable development goals 2030 of India. Case I depicts Indian present scenario of waste management where 164-735 tonnes/year of wastes would be generated for year 2001-2051. Further, 60% of waste can be treated in case II that help in reducing the land requirement up to 40% from estimated conditions of 2031 i.e., 83.8 × 107 m3. The case III is most ideal waste management condition for year 2031 to reduce 80% waste hence landfill requirement would minimize up to 16.76 × 107 m3 where population is at controlled conditions. This article concludes the formal handling and treatment of ISWM would minimize the landfilling, where LCA can be an antidote to achieve sustainable development goals.


Asunto(s)
Eliminación de Residuos , Administración de Residuos , Ciudades , Objetivos , India , Residuos Sólidos , Desarrollo Sostenible
7.
J Neurooncol ; 138(1): 29-39, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29354850

RESUMEN

Ependymomas (EPN) show site specific genetic alterations and a recent DNA methylation profiling study identified nine molecular subgroups. C11orf95-RELA and YAP1 fusions characterise the RELA and YAP1 molecular subgroups, respectively, of supratentorial (ST)-EPNs. Current guidelines recommend molecular subgrouping over histological grade for accurate prognostication. Clinicopathological features of ST-EPNs in correlation with C11orf95-RELA and YAP1 fusions have been assessed in only few studies. We aimed to study these fusions in EPNs, and identify diagnostic and prognostic markers. qRT-PCR and Sanger Sequencing for the detection of C11orf95-RELA, YAP1-MAMLD1 and YAP1-FAM118B fusion transcripts, gene expression analysis for NFKB1, and immunohistochemistry for p53, MIB-1, nestin, VEGF, and L1CAM were performed. 88 EPNs (10-Grade I and 78-Grade II/III) from all sites were included. RELA fusions were unique to Grade II/III ST-EPNs, detected in 81.4% (22/27) and 18.5% (5/27) of pediatric and adult ST-EPNs respectively. ST-EPNs harbouring RELA fusions showed frequent grade III histology (81.5%), clear cell morphology (70.3%), upregulated NFKB1 expression, MIB-1 labelling indices (LI) ≥ 10% (77.8%), and immunopositivity for nestin (95.7%), VEGF (72%), L1CAM (79%), and p53 (64%). Presence of RELA fusions, L1CAM immunopositivity and MIB-1 LI ≥ 10% associated with poor outcome. L1CAM showed 81% concordance with RELA fusions. YAP1-MAMLD1 fusion was identified in a single RELA fusion negative adult anaplastic ST-EPN. RELA fusions are frequent in ST-EPNs and associate with poor outcome. L1CAM is a surrogate immunohistochemical marker. RELA fusion positive ST-EPNs strongly express nestin indicating increased stemness. Further evaluation of the interactions between NFKB and stem cell pathways is warranted.


Asunto(s)
Ependimoma , FN-kappa B/metabolismo , Nestina/metabolismo , Molécula L1 de Adhesión de Célula Nerviosa/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias Supratentoriales , Factor de Transcripción ReIA/metabolismo , Adolescente , Adulto , Anciano , Niño , Preescolar , Ependimoma/metabolismo , Ependimoma/patología , Ependimoma/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Supervivencia sin Progresión , Estudios Retrospectivos , Transducción de Señal/fisiología , Neoplasias Supratentoriales/metabolismo , Neoplasias Supratentoriales/patología , Neoplasias Supratentoriales/fisiopatología , Adulto Joven
8.
J Neurooncol ; 139(1): 23-31, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29931616

RESUMEN

INTRODUCTION: Although role of individual microRNAs (miRNAs) in the pathogenesis of gliomas has been well studied, their role as a clustered remains unexplored in gliomas. METHODS: In this study, we performed the expression analysis of miR-379/miR-656 miRNA-cluster (C14MC) in oligodendrogliomas (ODGs) and also investigated the mechanism underlying modulation of this cluster. RESULTS: We identified significant downregulation of majority of the miRNAs from this cluster in ODGs. Further data from The Cancer Genome Atlas (TCGA) also confirmed the global downregulation of C14MC. Furthermore, we observed that its regulation is maintained by transcription factor MEF2. In addition, epigenetic machinery involving DNA and histone-methylation are also involved in its regulation, which is acting independently or in synergy. The post- transcriptionally regulatory network of this cluster showed enrichment of key cancer-related biological processes such as cell adhesion and migration. Also, there was enrichment of several cancer related pathways viz PIK3 signaling pathway and glioma pathways. Survival analysis demonstrated association of C14MC (miR-487b and miR-409-3p) with poor progression free survival in ODGs. CONCLUSION: Our work demonstrates tumor-suppressive role of C14MC and its role in pathogenesis of ODGs and therefore could be relevant for the development of new therapeutic strategies.


Asunto(s)
Neoplasias Encefálicas/metabolismo , MicroARNs/metabolismo , Oligodendroglioma/metabolismo , Adulto , Anciano , Encéfalo/metabolismo , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Biología Computacional , Metilación de ADN , Regulación hacia Abajo , Epigénesis Genética/fisiología , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Masculino , Persona de Mediana Edad , Oligodendroglioma/genética , ARN Mensajero/metabolismo , Transcripción Genética/fisiología
9.
Neuropathology ; 38(1): 22-33, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28901666

RESUMEN

Molecular and clinical characteristics of pediatric meningiomas are poorly defined. Therefore, we analyzed clinical, morphological and molecular profiles of pediatric meningiomas. Forty pediatric meningiomas from January 2002 to June 2015 were studied. 1p36, 14q32 and 22q-deletion were assessed by fluorescent in situ hybridization and mutations of most relevant exons of AKT, SMO, KLF4, TRAF and pTERT using sequencing. Expression of GAB1, stathmin, progesterone receptor (PR), p53 along with MIB-1 LI was examined using immunohistochemistry. There were 36 sporadic and four NF2 associated meningiomas. Among sporadic meningiomas, the majority (72.2%) of cases harbored 22q-deletion. Difference in frequency of combined 1p/14q deletion in Grade-I versus Grade-II/III tumors was not significant (13.7% vs 28.5%, P = 0.57). PR immunoreactivity was seen in 65.5% of Grade-I and 14.2% of Grade-II/III tumors (P = 0.03). The majority (97.2%) of meningiomas were immunonegative for p53. Stathmin and GAB co-expression was observed in 58.3% of cases. Notably, AKT, SMO, KLF4, TRAF7 (exon 17) and pTERT mutations were seen in none of the cases analyzed. 1p/14q codeletion was frequent in skull base as compared to non-skull base meningiomas (23% vs 11.1%, P = 0.37). All NF2 meningiomas harbored 22q-deletion and showed GAB and stathmin co-expression while none showed 1p/14q loss. Pediatric meningiomas share certain phenotypic and cytogenetic characteristics with adult counterparts, but GAB and stathmin co-expression in the majority of cases and non-significant difference in frequency of 1p/14q co-deletion between low- and high-grade meningiomas indicate an inherently aggressive nature. Characteristic AKT/SMO, KLF4/TRAF7 and pTERT genetic alterations seen in adults are distinctly absent in pediatric meningiomas.


Asunto(s)
Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patología , Meningioma/genética , Meningioma/patología , Adolescente , Biomarcadores de Tumor/análisis , Niño , Preescolar , Femenino , Humanos , Factor 4 Similar a Kruppel , Masculino
10.
Carcinogenesis ; 38(2): 152-161, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27993893

RESUMEN

Enhancer of zeste homolog-2(EZH2) is a key epigenetic regulator that functions as oncogene and also known for inducing altered trimethylation of histone at lysine-27 (H3K27me3) mark in various tumors. However, H3K27me3 targets and their precise relationship with gene expression are largely unknown in astrocytic tumors. In this study, we checked EZH2 messenger RNA and protein expression in 90 astrocytic tumors of different grades using quantitative PCR and immunohistochemistry, respectively. Further, genome-wide ChIP-seq analysis for H3K27me3 modification was also performed on 11 glioblastomas (GBMs) and 2 diffuse astrocytoma (DA) samples. Our results showed EZH2 to be highly overexpressed in astrocytic tumors with a significant positive correlation with grade. Interestingly, ChIP-seq mapping revealed distinct differences in genes and pathways targeted by these H3K27me3 modifications between GBM versus DA. Neuroactive ligand receptor pathway was found most enriched in GBM (P = 9.4 × 10-25), whereas DA were found to be enriched in metabolic pathways. Also, GBM showed a higher enrichment of H3K27me3 targets reported in embryonic stem cells and glioma stem cells as compared with DAs. Our results show majority of these H3K27me3 target genes were downregulated, not only due to H3K27me3 modification but also due to concomitant DNA methylation. Further, H3K27me3 modification-associated gene silencing was not restricted to promoter but also present in gene body and transcription start site regions. To the best of our knowledge, this is the first high-resolution genome-wide mapping of H3K27me3 modification in adult astrocytic primary tissue samples of human, highlighting the differences between grades. Interestingly, we identified SLC25A23 as important target of H3K27me3 modification, which was downregulated in GBM and its low expression was associated with poor prognosis in GBMs.


Asunto(s)
Antiportadores/genética , Astrocitoma/genética , Metilación de ADN/genética , Proteína Potenciadora del Homólogo Zeste 2/genética , Glioblastoma/genética , N-Metiltransferasa de Histona-Lisina/genética , Proteínas Mitocondriales/genética , Astrocitoma/patología , Línea Celular Tumoral , Elementos de Facilitación Genéticos/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Genoma Humano , Glioblastoma/patología , N-Metiltransferasa de Histona-Lisina/metabolismo , Humanos , Masculino , Clasificación del Tumor , Regiones Promotoras Genéticas
11.
J Neurochem ; 143(6): 671-683, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28833137

RESUMEN

Elevated expression of enhancer of zeste homolog 2 (EZH2), a histone H3K27 methyltransferase, was observed in gliomas harboring telomerase reverse transcriptase (TERT) promoter mutations. Given the known involvement of TERT and EZH2 in glioma progression, the correlation between the two and subsequently its involvement in metabolic programming was investigated. Inhibition of human telomerase reverse transcriptase either pharmacologically or through genetic manipulation not only decreased EZH2 expression, but also (i) abrogated FASN levels, (ii) decreased de novo fatty acid accumulation, and (iii) increased ataxia-telangiectasia-mutated (ATM) phosphorylation levels. Conversely, diminished TERT and FASN levels upon siRNA-mediated EZH2 knockdown indicated a positive correlation between TERT and EZH2. Interestingly, ATM kinase inhibitor rescued TERT inhibition-mediated decrease in FASN and EZH2 levels. Importantly, TERT promoter mutant tumors exhibited greater microsatellite instability, heightened FASN levels and lipid accumulation. Coherent with in vitro findings, pharmacological inhibition of TERT by costunolide decreased lipid accumulation and elevated ATM expression in heterotypic xenograft glioma mouse model. By bringing TERT-EZH2 network at the forefront as driver of dysregulated metabolism, our findings highlight the non-canonical but distinct role of TERT in metabolic reprogramming and DNA damage responses in glioblastoma.


Asunto(s)
Daño del ADN/fisiología , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Glioblastoma/metabolismo , Metabolismo de los Lípidos/fisiología , Telomerasa/metabolismo , Animales , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/fisiología , Glioblastoma/patología , Xenoinjertos , Humanos , Ratones , Ratones Desnudos
12.
J Neurooncol ; 133(3): 487-495, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28500561

RESUMEN

Craniopharyngiomas (CP) are rare benign epithelial tumors, with two histological variants, namely the adamantinomatous variant (ACP) and the rarer papillary variant (PCP). They are locally infiltrative and surgically challenging tumors with severe long term morbidity. CTNNB1 mutations with ß-catenin immunopositivity and BRAFV600E mutations with anti-VE immunopositivity have been recently described in ACPs and PCPs respectively. We aimed to study BRAF and CTNNB1 gene mutations in CPs operated at our institute, and correlate it with clinicopathological parameters including histopathology and immunohistochemistry (IHC) for proteins VE-1 and ß-catenin. A total of 54 CPs diagnosed over 3-year duration were included. IHC for ß-catenin and VE-1 proteins, and Sanger sequencing for CTNNB1 (exon 3) and BRAF (exon 15) genes were performed. CTNNB1 mutations were identified in 63% (27/43) of ACPs while nuclear immunopositivity for ß-catenin was observed in 79% (34/43) of them. Seven ACPs showed ß-catenin immunopositivity in the absence of mutations. BRAFV600E (p.Val600Glu) mutations were observed in 57% of PCPs (4/7), while cytoplasmic immunopositivity for anti-VE1 antibody was observed only in 43% of PCPs (3/7), all of which also harboured BRAFV600E mutations. The mutations and IHC staining patterns of ACPs and PCPs were non-overlapping. Four cases with uncertain histological pattern could be subcategorised into specific variants only following mutation analysis/IHC. The identification of hallmark molecular signatures in the two CP variants holds promise for alternate improved treatment modalities, emphasizing the need for sub-categorization in routine histopathology reporting. IHC for ß-catenin and targeted sequencing for BRAFV600E serve as useful adjuncts.


Asunto(s)
Craneofaringioma/genética , Craneofaringioma/patología , Neoplasias Hipofisarias/genética , Neoplasias Hipofisarias/patología , Proteínas Proto-Oncogénicas B-raf/genética , beta Catenina/genética , Adolescente , Adulto , Niño , Craneofaringioma/metabolismo , Citoplasma/metabolismo , Citoplasma/patología , Análisis Mutacional de ADN , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Mutación , Neoplasias Hipofisarias/metabolismo , Estudios Retrospectivos , beta Catenina/metabolismo
13.
Neurol India ; 65(5): 1076-1082, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28879901

RESUMEN

BACKGROUND: Gangliogliomas (GGs) are slow-growing glioneuronal tumors seen in children and young adults. They are associated with intractable epilepsy, and have recently been found to harbor BRAF (B- rapidly accelerated fibrosarcoma) gene mutations. However, the mammalian target of rapamycin (mTOR) signaling pathway, downstream of BRAF, has not been evaluated extensively in GGs. MATERIALS AND METHODS: GG cases were retrieved, clinical data obtained, and histopathological features reviewed. Sequencing for BRAF V600E mutation, analysis of BRAF copy number by quantitative real-time polymerase chain reaction, and immunohistochemistry for mTOR pathway markers p-S6 and p-4EBP1 were performed. RESULTS: Sixty-four cases of GG were identified (0.9% of central nervous system tumors). Of these, 28 had sufficient tumor tissue for further evaluation. Mixed glial and neuronal morphology was the commonest (64%) type. Focal cortical dysplasia was identified in the adjacent cortex (6 cases). BRAF V600E mutation was identified in 30% of GGs; BRAF copy number gain was observed in 50% of them. p-S6 and p-4EBP1 immunopositivity was seen in 57% cases each. Thus, mTOR pathway activation was seen in 81% cases, and was independent of BRAF alterations. 87% patients had Engel grade I outcome, while 13% had Engel grade II outcome. Both the Engel grade II cases analyzed showed BRAF V600E mutation. CONCLUSION: BRAF V600E mutation is frequent in GGs, as is BRAF gain; the former may serve as a target for personalized therapy in patients with residual tumors, necessitating its assessment in routine pathology reporting of these tumors. Evidence of mTOR pathway activation highlights similarities in the pathogenetic mechanisms underlying GG and focal cortical dysplasia, and suggests that mTOR inhibitors may be of utility in GG patients with persistent seizures after surgery.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Ganglioglioma/genética , Ganglioglioma/metabolismo , Proteínas Proto-Oncogénicas B-raf/genética , Serina-Treonina Quinasas TOR/metabolismo , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Estudios Retrospectivos , Transducción de Señal/fisiología , Adulto Joven
14.
AAPS PharmSciTech ; 18(3): 710-720, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27222025

RESUMEN

Surface modification of liposomes with targeting ligands is known to improve the efficacy with reduced untoward effects in treating infective diseases like visceral leishmaniasis (VL). In the present study, modified ligand (ML), designed by modifying polysaccharide with a long chain lipid was incorporated in liposomes with the objective to target amphotericin B (Amp B) to reticuloendothelial system and macrophages. Conventional liposomes (CL) and surface modified liposomes (SML) were characterized for size, shape, and entrapment efficiency (E.E.). Amp B SML with 3% w/w of ML retained the vesicular nature with particle size of ∼205 nm, E.E. of ∼95% and good stability. SML showed increased cellular uptake in RAW 264.7 cells which could be attributed to receptor-mediated endocytosis. Compared to Amp B solution, Amp B liposomes exhibited tenfold increased safety in vitro in RAW 264.7 and J774A.1 cell lines. Pharmacokinetics and biodistribution studies revealed high t 1/2, area under the curve (AUC)0-24, reduced clearance and prolonged retention in liver and spleen with Amp B SML compared to other formulations. In promastigote and amastigote models, Amp B SML showed enhanced performance with low 50% inhibitory concentration (IC50) compared to Amp B solution and Amp B CL. Thus, due to the targeting ability of ML, SML has the potential to achieve enhanced efficacy in treating VL.


Asunto(s)
Anfotericina B/química , Anfotericina B/farmacología , Leishmaniasis Visceral/tratamiento farmacológico , Liposomas/química , Anfotericina B/farmacocinética , Animales , Línea Celular , Química Farmacéutica/métodos , Hígado/parasitología , Macrófagos/parasitología , Ratones , Tamaño de la Partícula , Bazo/parasitología , Distribución Tisular
15.
Exp Mol Pathol ; 100(2): 312-20, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26892683

RESUMEN

This study aims to analyze expression of EZH2 and DNA-methyltransferases (DNMT1, 3A and 3B) in astrocytic tumors and investigate their link as well as their correlation with survival, especially in GBMs. Expression of EZH2 and DNMTs (DNMT1, DNMT3A and DNMT3B) in different grades of astrocytomas (n=93) was assessed by qRT-PCR and immunohistochemistry. GBM-U87MG cell line was used for functional studies. Strong immunopositivity (LI≥25%) for EZH2, DNMT1 and DNMT3B was detected in 52%, 56% and 64% cases of GBMs respectively, which was significantly higher as compared to Grade II/III cases. Similarly, their median fold change of mRNA expression was also significantly higher in GBMs. There was also a significant positive correlation between DNMT1/DNMT3B and EZH2 mRNA and protein expression, which was in concordance with TCGA data set. Inhibition of DNMTs in cell line by Azacytidine resulted in down-regulation of EZH2, while knock-down of EZH2 by siRNA was not associated with any significant alteration of DNMTs, indicating that EZH2 expression in GBMs is possibly regulated by DNMTs, but not the reverse. Strong immunopositivity for EZH2, DNMT1 and DNMT3B were individually associated with significantly shorter survival and showed no correlation with IDH1 mutation status. In addition, the combination of these 3 markers represented an independent prognostic signature with cases having weak/negative expression of all 3 markers being associated with best prognosis. For the first time, the present study describes an epigenetic prognostic signature in GBMs based on immunohistochemical expression of EZH2, DNMT1 and 3B which can be used easily in routine neuropathology practice.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasas/genética , Regulación Neoplásica de la Expresión Génica , Glioblastoma/genética , Complejo Represivo Polycomb 2/genética , Azacitidina/farmacología , Línea Celular Tumoral , ADN (Citosina-5-)-Metiltransferasa 1 , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Proteína Potenciadora del Homólogo Zeste 2 , Inhibidores Enzimáticos/farmacología , Epigénesis Genética/efectos de los fármacos , Epigénesis Genética/genética , Femenino , Perfilación de la Expresión Génica , Glioblastoma/metabolismo , Glioblastoma/terapia , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Análisis Multivariante , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Pronóstico , Modelos de Riesgos Proporcionales , Interferencia de ARN , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , ADN Metiltransferasa 3B
16.
Neuropathology ; 36(5): 490-495, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27121356

RESUMEN

Ependymomas are gliomas that recapitulate the ependymal cells microscopically and ultrastructurally. They commonly occur along the ventricular surfaces and central canal of the brain and spinal cord. Intracranial extra-axial ependymoma (IEAE) is a rare entity and is commonly misdiagnosed clinically and radiologically as a meningioma. The histogenesis of such IEAEs is obscure. A novel recurrent oncogenic fusion involving the C11orf95 and RELA genes was recently described in supratentorial ependymomas. A 9-year-old girl presented with a dural based parafalcine mass that, in addition to exhibiting classical immunohistochemical features of an ependymoma, also demonstrated C11orf95-RELA fusion, characteristic of supratentorial ependymomas. We suggest that IEAEs share their histogenesis with their intra-axial counterparts, arising either from dural extension of subcortical, subependymal rests or directly from ectopic dural rests.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Ependimoma/genética , Ependimoma/patología , Proteínas/genética , Factor de Transcripción ReIA/genética , Encéfalo/ultraestructura , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/ultraestructura , Niño , Ependimoma/diagnóstico por imagen , Femenino , Fusión Génica , Humanos
17.
Neurol India ; 64(5): 988-94, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27625244

RESUMEN

BACKGROUND: Subependymal giant cell astrocytomas (SEGA) are slow-growing benign intraventricular tumors, the pathogenesis of which is debated. Recent studies have shown that tuberous sclerosis complex (TSC) 1 and TSC2 genes are linked to the mammalian target of rapamycin (mTOR) cell signaling pathway. We aimed to analyze TSC1 and TSC2 gene mutation, hamartin and tuberin protein expression, and protein expression of mTOR signaling cascade in a series of SEGA to determine their role in pathogenesis. MATERIALS AND METHODS: Twenty-eight SEGA cases were retrieved from archival material. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded tissue using antibodies against tuberin, hamartin, phospho-p70S6 kinase, S6 ribosomal protein, phospho-S6 ribosomal protein, phospho-4E-BP1, Stat3, and phospho-Stat3. Mutation analysis of TSC1 (exons 15 and 17) and TSC2 (exons 33, 39, and 40) was done by DNA sequencing. RESULTS: Loss of immunoexpression of either hamartin or tuberin was found in 19 cases (68%). Pathogenic point mutations in selected exons of TSC1 and TSC2 genes were present in 5 of 20 cases studied. Robust expression of mTOR downstream signaling molecules phospho-p70S6 kinase (100%), S6 ribosomal protein (82%), phospho-S6 ribosomal protein (64%), phospho-4E-BP1 (64%), and Stat3 (100%) was seen. Four cases (14%) showed immunopositivity for phospho-Stat3. There was no significant correlation of these markers with immunoloss of tuberin and hamartin. SIGNIFICANCE: There is a definite role for TSC1 and TSC2 genes in the pathogenesis of SEGA as evidenced by loss of protein expression and presence of mutations. Strong expression of mTOR downstream signaling proteins indicates activation of mTOR pathway in these tumors, suggesting that proteins in this pathway may have the potential to serve as therapeutic targets in these patients.


Asunto(s)
Astrocitoma/genética , Transducción de Señal , Serina-Treonina Quinasas TOR/fisiología , Proteínas Supresoras de Tumor/fisiología , Proteínas Adaptadoras Transductoras de Señales , Astrocitoma/metabolismo , Proteínas de Ciclo Celular , Análisis Mutacional de ADN , Humanos , Inmunohistoquímica , Fosfoproteínas , Proteína S6 Ribosómica , Esclerosis Tuberosa , Proteína 1 del Complejo de la Esclerosis Tuberosa , Proteína 2 del Complejo de la Esclerosis Tuberosa
18.
Int J Cancer ; 137(10): 2343-53, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25994230

RESUMEN

Pediatric high-grade gliomas (HGGs) are highly malignant tumors that remain incurable and relatively understudied. The crucial role of noncoding RNAs (ncRNAs) has been reported in various cancers. However, the study on miRNAs in pediatric HGGs is scant and there is no report till date on the status of other small ncRNAs. Genome-wide microarray analysis was performed to investigate small ncRNA expression in pediatric HGG (n = 14) and compared to adult glioblastoma (GBM) signature. The validation of miRNAs and small nucleolar RNAs (snoRNAs) was done by real-time polymerase chain reaction. TP53 and H3F3A mutation-specific miRNA and snoRNA profiles were generated and analyzed. Pediatric HGGs showed upregulation of miR-17/92 and its paralog clusters (miR106b/25 and miR-106a/363), whereas majority of downregulated miRNAs belonged to miR379/656 cluster (14q32). Unsupervised hierarchical clustering identified two distinct groups. Interestingly, Group 2 with downregulated 14q32 cluster showed better overall survival. The miRNAs unique to pediatric HGG as compared to adult GBM were predicted to affect PDGFR and SMAD2/3 pathways. Similarities were seen between pediatric HGG and TP53 mutant miRNA profiles as compared to wild types. Several of H3F3A mutation-regulated genes were found to be the targets of H3F3A mutant-specific miRNAs. Remarkably, a significant downregulation of HBII-52 snoRNA cluster was found in pediatric HGGs, and was specific to H3F3A nonmutants. This is the first genome-wide profiling study on miRNAs and snoRNAs in pediatric HGGs with respect to H3F3A and TP53 mutations. The comparison of miRNA profiles of pediatric HGGs and adult GBM reiterates the overlaps and differences as also seen with their gene expression and methylation signatures.


Asunto(s)
Neoplasias Encefálicas/genética , Glioma/genética , Histonas/genética , MicroARNs/genética , ARN Nucleolar Pequeño/genética , Proteína p53 Supresora de Tumor/genética , Adolescente , Adulto , Neoplasias Encefálicas/patología , Niño , Preescolar , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Glioma/patología , Humanos , Mutación , Análisis de Supervivencia
19.
J Neurooncol ; 121(3): 489-97, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25479829

RESUMEN

Mutations in H3.3-ATRX-DAXX chromatin remodeling pathway have been reported in pediatric GBMs. H3.3 (H3F3A) mutations may affect transcriptional regulation by altered global histone-methylation. Therefore, we analyzed yet partly understood global histone code (H3K-4/9/27/36) trimethylation pattern in H3F3A-ATRX mutants and wild-type. H3F3A, HIST1H3B, IDH1, ATRX, DAXX and Tp53 mutations were identified by sequencing/immunohistochemistry in 27 pediatric GBMs. Global histone-methylation H3K-4/9/27/36me3 and Polycomb-protein EZH2 expression were evaluated by immunohistochemistry. H3F3A-ATRX mutation was observed in 66.7 % (18/27) of pediatric GBMs. K27M and G34R-H3F3A mutations were found in 37 % (10/27) and 14.8 % (4/27) patients respectively. G34V-H3F3A, HIST1H3B and IDH1 mutations were absent. Notably, commonest global histone-methylation mark lost was H3K27me3 (17/25, 68 %) followed by H3K4me3 (45.5 %, 10/22) and H3K9me3 (18.2 %, 4/22). Global H3K36me3 showed no loss. Most significant observation was loss of one or more histone-trimethylation mark in 80 % (20/25) pediatric GBMs. Notably, simultaneous loss of H3K27me3 and H3K4me3 were present in 7/22 (31.8 %) of pediatric GBMs. Low expression of EZH2 was found in 12/24 (50 %) of cases. However no significant correlation of loss of histone-marks or EZH2 expression with H3F3A-ATRX mutants (loss of at least one histone-marks in 87.5 % (14/16) cases) versus wild-types (loss of at least one histone-marks in 75 % (6/8) cases) was seen. The present study highlights for the first time combinatorial loss of one or more histone-trimethylation marks associated with majority of pediatric GBMs and the finding suggests significant role of histone-code in the molecular biology that underlies pediatric GBMs. Hence therapies for patients with particular combinations of histone modifications present opportunity to design innovative patient-tailored treatment protocols.


Asunto(s)
ADN Helicasas/genética , Metilación de ADN/genética , Análisis Mutacional de ADN , Glioblastoma/genética , Histonas/genética , Proteínas Nucleares/genética , Niño , Femenino , Humanos , Inmunohistoquímica , Masculino , Estudios Retrospectivos , Proteína Nuclear Ligada al Cromosoma X
20.
Chemosphere ; 357: 142053, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38636917

RESUMEN

Emerging organic contaminants present in the environment can be biodegraded in anodic biofilms of microbial fuel cells (MFCs). However, there is a notable gap existing in deducing the degradation mechanism, intermediate products, and the microbial communities involved in degradation of broad-spectrum antibiotic such as triclosan (TCS). Herein, the possible degradation of TCS is explored using TCS acclimatized biofilms in MFCs. 95% of 5 mgL-1 TCS are been biodegraded within 84 h with a chemical oxygen demand (COD) reduction of 62% in an acclimatized-MFC (A-MFC). The degradation of TCS resulted in 8 intermediate products including 2,4 -dichlorophenol which gets further mineralized within the system. Concurrently, the 16S rRNA V3-V4 sequencing revealed that there is a large shift in microbial communities after TCS acclimatization and MFC operation. Moreover, 30 dominant bacterial species (relative intensity >1%) are identified in the biofilm in which Sulfuricurvum kujiense, Halomonas phosphatis, Proteiniphilum acetatigens, and Azoarcus indigens significantly contribute to dihydroxylation, ring cleavage and dechlorination of TCS. Additionally, the MFC was able to produce 818 ± 20 mV voltage output with a maximum power density of 766.44 mWm-2. The antibacterial activity tests revealed that the biotoxicity of TCS drastically reduced in the MFC effluent, signifying the non-toxic nature of the degraded products. Hence, this work provides a proof-of-concept strategy for sustainable mitigation of TCS in wastewaters with enhanced bioelectricity generation.


Asunto(s)
Bacterias , Biodegradación Ambiental , Fuentes de Energía Bioeléctrica , Biopelículas , Triclosán , Triclosán/metabolismo , Bacterias/metabolismo , Contaminantes Químicos del Agua/metabolismo , ARN Ribosómico 16S , Clorofenoles/metabolismo , Catálisis
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