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1.
Cell ; 174(4): 803-817.e16, 2018 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-30057114

RESUMO

Acquired chromosomal DNA amplifications are features of many tumors. Although overexpression and stabilization of the histone H3 lysine 9/36 (H3K9/36) tri-demethylase KDM4A generates transient site-specific copy number gains (TSSGs), additional mechanisms directly controlling site-specific DNA copy gains are not well defined. In this study, we uncover a collection of H3K4-modifying chromatin regulators that function with H3K9 and H3K36 regulators to orchestrate TSSGs. Specifically, the H3K4 tri-demethylase KDM5A and specific COMPASS/KMT2 H3K4 methyltransferases modulate different TSSG loci through H3K4 methylation states and KDM4A recruitment. Furthermore, a distinct chromatin modifier network, MLL1-KDM4B-KDM5B, controls copy number regulation at a specific genomic locus in a KDM4A-independent manner. These pathways comprise an epigenetic addressing system for defining site-specific DNA rereplication and amplifications.


Assuntos
Cromatina/metabolismo , Variações do Número de Cópias de DNA , Metilação de DNA , Histonas/metabolismo , Lisina/metabolismo , Proteína 2 de Ligação ao Retinoblastoma/metabolismo , Ciclo Celular , Células HEK293 , Humanos , Proteína 2 de Ligação ao Retinoblastoma/genética
3.
Indian J Clin Biochem ; 37(2): 185-191, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35463103

RESUMO

The aim of the study is to evaluate the stability and longevity of the paper-based screening test for the sickle cell disease in relation to different temperatures and storage time. Blood stain patterns were interpreted after spotting the blood-buffer mixture (phosphate buffer, saponin and sodium metabisulfite) on chromatographic paper (Whatman no. 3). The stability of the buffer was tested after keeping the buffer at different temperature for 24 h. Longevity of the buffer was tested post storage for various time intervals. Test indicated reproducibility with the buffer stored at 4°C. The 15% metabisulfite buffer was found to be stable up to 180 days at 4°C and showed accurate identification of all genotypes. The tests revealed 100% sensitivity and 100% specificity in identification of HbS. However, the sensitivity of differentiation between sickle cell trait (AS) with disease (SS) was found to be 97.7% with 100% specificity. The paper-based screening test may be used as a method of choice for the screening of sickle cell anemia in community-based screening programs. The low-cost, rapid, and accurate point of care testing tools offer an avenue for effective screening in developing nations.

4.
Ann Hematol ; 100(2): 365-373, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33388857

RESUMO

Sickle cell disease has varied clinical symptoms, and patients having high fetal hemoglobin (HbF) have milder symptoms. Various genetic factors are known to modulate the HbF levels. Krüppel-like factor 1 (KLF1) is a transcription factor that regulates the beta-like globin gene expression. Any variation in KLF1 gene may alter the sickle cell disease phenotype. Xmn-I polymorphism is also known to regulate the gamma globin gene expression. Present studies were carried out to investigate the effect of KLF1 gene mutations and Xmn-I polymorphism on the sickle cell disease severity and to ascertain the genotype-phenotype correlation. One hundred and eighteen sickle cell disease patients having a median follow-up of 5 years (3-10 years) were recruited. Clinical details were recorded from their retrospective medical records. Xmn-I polymorphism were analyzed using PCR-RFLP method. Variations in KLF1 gene were identified using Sanger sequencing. Out of 118 patients, 24 had acute chest syndrome and 21 patients had more than 2 pain episodes per year. There were no significant differences in sickle cell disease-related morbidities in male and females barring leg ulcers. A total of 6 polymorphism were observed in KLF1 gene, out of which 3 are novel (c.-304G > C, c.*141A > G and c.*178A > G). No statistically significant association of any of SNPs identified in KLF1 gene or Xmn-I polymorphism was seen with HbF levels as well as the sickle cell disease-related morbidities. No association exists between fetal hemoglobin or sickle cell disease-related morbidities and Xmn-I polymorphism or with SNPs identified in KLF1 gene in the studied cohort.


Assuntos
Síndrome Torácica Aguda/genética , Fatores de Transcrição Kruppel-Like/genética , Úlcera da Perna/genética , Mutação , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino
5.
Malar J ; 20(1): 229, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34020652

RESUMO

BACKGROUND: Malaria is a major public health problem in India and accounts for about 88% of malaria burden in South-East Asia. India alone accounted for 2% of total malaria cases globally. Anti-malarial drug resistance is one of the major problems for malaria control and elimination programme. Artemether-lumefantrine (AL) is the first-line treatment of uncomplicated Plasmodium falciparum in north eastern states of India since 2013 after confirming the resistance against sulfadoxine-pyrimethamine. In the present study, therapeutic efficacy of artemether-lumefantrine and k13 polymorphism was assessed in uncomplicated P. falciparum malaria. METHODS: This study was conducted at four community health centres located in Koraput district of Odisha, Bastar district of Chhattisgarh, Balaghat district of Madhya Pradesh and Gondia district of Maharashtra state. Patients with uncomplicated P. falciparum malaria were administered with fixed dose combination (6 doses) of artemether-lumefantrine for 3 days and clinical and parasitological response was recorded up to 28 days as per World Health Organization protocol. Nucleotide sequencing of msp1 and msp2 gene was performed to differentiate between recrudescence and reinfection. Amplification and sequencing of k13 propeller gene region covering codon 450-680 was also carried out to identify the polymorphism. RESULTS: A total 376 malaria patients who fulfilled the enrolment criteria as well as consented for the study were enrolled. Total 356 patients were followed up successfully up to 28 days. Overall, the adequate clinical and parasitological response was 98.9% and 99.4% with and without PCR correction respectively. No case of early treatment failure was observed. However, four cases (1.1%) of late parasitological failure were found from the Bastar district of Chhattisgarh. Genotyping of msp1 and msp2 confirmed 2 cases each of recrudescence and reinfection, respectively. Mutation analysis of k13 propeller gene showed one non-synonymous mutation Q613H in one isolate from Bastar. CONCLUSIONS: The study results showed that artemether-lumefantrine is highly effective in the treatment of uncomplicated P. falciparum malaria among all age groups. No functional mutation in k13 was found in the study area. The data from this study will be helpful in implementation of artemether-lumefantrine in case of treatment failure by artesunate plus sulfadoxine-pyrimethamine.


Assuntos
Antimaláricos/uso terapêutico , Combinação Arteméter e Lumefantrina/uso terapêutico , Doenças Endêmicas/prevenção & controle , Malária Falciparum/prevenção & controle , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Índia , Lactente , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum/efeitos dos fármacos , Adulto Jovem
6.
J Nanosci Nanotechnol ; 17(4): 2525-530, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29652120

RESUMO

Guanidino-graphene has been synthesized by the reaction of bromoamine with reduced graphene oxide and characterized by FT-IR, Raman, TGA, powder XRD, TEM, SEM, and zeta potential. It is a cheap, heterogeneous and environmentally benign solid base catalyst used for cascade Aldol-Michael-oxidation in the synthesis of chalcone, flavonoids.

7.
Malar J ; 15(1): 498, 2016 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-27737665

RESUMO

BACKGROUND: Anti-malarial drug resistance continues to be a leading threat to malaria control efforts and calls for continued monitoring of waning efficacy of artemisinin-based combination therapy (ACT). Artesunate + sulfadoxine/pyrimethamine (AS + SP) is used for the treatment of uncomplicated Plasmodium falciparum malaria in India. However, resistance against AS + SP is emerged in northeastern states. Therefore, artemether-lumefantrine (AL) is the recommended first line treatment for falciparum malaria in north eastern states. This study investigates the therapeutic efficacy and safety of AL for the treatment of uncomplicated falciparum malaria in three malaria-endemic states in India. The data generated through this study will benefit the immediate implementation of second-line ACT as and when required. METHODS: This was a one-arm prospective evaluation of clinical and parasitological responses for uncomplicated falciparum malaria using WHO protocol. Patients diagnosed with uncomplicated mono P. falciparum infection were administered six-dose regimen of AL over 3 days and subsequent follow-up was carried out up to 28 days. Molecular markers msp-1 and msp-2 were used to differentiate recrudescence and re-infection and K13 propeller gene was amplified and sequenced covering the codon 450-680. RESULTS: A total of 402 eligible patients were enrolled in the study from all four sites. Overall, adequate clinical and parasitological response (ACPR) was 98 % without PCR correction and 99 % with PCR correction. At three study sites, ACPR rates were 100 %, while at Bastar, cure rate was 92.5 % on day 28. No early treatment failure was found. The PCR-corrected endpoint finding confirmed that one late clinical failure (LCF) and two late parasitological failures (LPF) were recrudescences. The PCR corrected cure rate was 96.5 %. The mean fever clearance time was 27.2 h ± 8.2 (24-48 h) and the mean parasite clearance time was 30.1 h ± 11.0 (24-72 h). Additionally, no adverse event was recorded. Analysis of total 186 samples revealed a mutation in the k13 gene along with non-synonymous mutation at codon M579T in three (1.6 %) samples. CONCLUSION: AL is an efficacious drug for the treatment of uncomplicated falciparum malaria. However, regular monitoring of AL is required in view of malaria elimination initiatives, which will be largely dependent on therapeutic interventions, regular surveillance and targeted vector control.


Assuntos
Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Etanolaminas/uso terapêutico , Fluorenos/uso terapêutico , Malária Falciparum/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Protozoários/genética , Antimaláricos/efeitos adversos , Combinação Arteméter e Lumefantrina , Artemisininas/efeitos adversos , Criança , Pré-Escolar , Combinação de Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Etanolaminas/efeitos adversos , Fluorenos/efeitos adversos , Humanos , Índia , Lactente , Proteína 1 de Superfície de Merozoito/genética , Pessoa de Meia-Idade , Plasmodium falciparum/classificação , Plasmodium falciparum/genética , Plasmodium falciparum/isolamento & purificação , Estudos Prospectivos , Proteínas de Protozoários/genética , Análise de Sequência de DNA , Resultado do Tratamento , Adulto Jovem
8.
Mol Cancer ; 13: 212, 2014 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-25216674

RESUMO

BACKGROUND: p57(Kip2), a cyclin-dependent kinase inhibitor, is considered to be a candidate tumor suppressor gene that has been implicated in Beckwith-Wiedemann syndrome and sporadic cancers. In addition, decreased expression of p57(Kip2) protein has been frequently observed in pancreatic, lung, breast, bladder, gastrointestinal tract and prostate cancers. However, p57(Kip2) gene mutations are rare in these cancers suggesting that other unknown mechanisms might be at play in reducing its expression. The aim of this study was to investigate the molecular mechanism of down-regulation of p57(Kip2) in prostate cancer. FINDINGS: We observed a significant negative correlation between the expression of p57(Kip2) and microRNA-21 (miR-21) in prostate cancer samples and after androgen deprivation with castration in the CWR22 human prostate cancer xenograft model. We report that miR-21 targeted the coding region and decreased p57(Kip2) mRNA and protein levels in prostate cancer cells. Conversely, inhibition of endogenous miR-21 by an anti-miR-21 inhibitor strongly induced p57(Kip2) expression. Furthermore, we found that knockdown of p57(Kip2) reversed the effects of the anti-miR-21 inhibitor on cell migration and anchorage-independent cell growth. CONCLUSIONS: Our results indicate that miR-21 is able to downregulate p57(Kip2) expression by targeting the coding region of the gene and is also able to attenuate p57(Kip2) mediated functional responses. This is the first report demonstrating that p57(Kip2) is a novel target of miR-21 in prostate cancer and revealing a novel oncogenic function of this microRNA.


Assuntos
Inibidor de Quinase Dependente de Ciclina p57/genética , Inibidor de Quinase Dependente de Ciclina p57/metabolismo , MicroRNAs/metabolismo , Neoplasias da Próstata/genética , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , MicroRNAs/genética , Transplante de Neoplasias , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo
9.
Trop Med Int Health ; 18(1): 12-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23107370

RESUMO

OBJECTIVE: During an epidemiological study (January-July 2012) on malaria in forest villages of Central India, Plasmodium malariae-like malaria parasites were observed in blood smears of fever cases. We aimed to confirm the presence of P. malariae using molecular tools i.e. species-specific nested polymerase chain reaction (PCR) and DNA sequencing. METHODS: All fever cases or cases with history of fever in 25 villages of Balaghat district were screened for malaria parasite using bivalent rapid diagnostic test and microscopy after obtaining written informed consent. Nested PCR was employed on microscopically suspected P. malariae cases. DNA sequences in the target region for PCR diagnosis were analysed for all the suspected cases of P. malariae. RESULTS: Among the 22 microscopy suspected P. malariae cases, nested PCR confirmed the identity of P. malariae in 19 cases. Among these 14 were mono P. malariae infections, three were mixed infection of P. malariae with Plasmodium falciparum and two were mixed infection of P. malariae with Plasmodium vivax. Clinically P. malariae subjects generally presented with fever and headache. However, the typical 3-day pattern of quantum malaria was not observed. The parasite density of P. malariae was significantly lower than that of P. vivax and P. falciparum. DISCUSSIONS: Plasmodium malariae may have been in existence in forest villages of central India but escaped identification due to its close resemblance to P. vivax. The results re-affirm the importance of molecular methods of testing on routine basis for efficacious control strategies against malaria.


Assuntos
Febre/parasitologia , Controle de Infecções/métodos , Malária/parasitologia , Plasmodium malariae , Adolescente , Adulto , Idoso , Técnicas de Tipagem Bacteriana , Criança , Pré-Escolar , DNA de Protozoário , Febre/sangue , Febre/etiologia , Humanos , Índia , Lactente , Malária/sangue , Malária/diagnóstico , Malária/prevenção & controle , Microscopia , Pessoa de Meia-Idade , Plasmodium falciparum/genética , Plasmodium malariae/genética , Plasmodium vivax/genética , Reação em Cadeia da Polimerase , População Rural , Árvores , Adulto Jovem
10.
Front Microbiol ; 14: 1260812, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37779723

RESUMO

Introduction: Dengue fever is hyperendemic in several Southeast and South Asian countries, including India, with all four serotypes (DENV 1-4) circulating at different periods and in different locations. Sustainable and improved virological and entomological surveillance is the only tool to prevent dengue and other vector-borne diseases. Objectives: The present study has been carried out to detect and characterize the circulating dengue virus (DENV) in field-collected Aedes mosquitoes in Bhopal, Central India. Methods: Aedes mosquitoes were collected from 29 localities within Bhopal city during October 2020 to September 2022. DENV infection was assessed in the individual head and thorax regions of Aedes mosquitoes using reverse transcriptase PCR. Positive samples were sequenced, and the circulating serotypes and genotypes were determined using phylogenetic analysis. Results: DENV RNA was detected in 7 Aedes aegypti and 1 Aedes albopictus, with infection rates of 0.59 and 0.14%, respectively. Phylogenetic analysis revealed all the isolates belonged to DENV serotype 2 and distinctly clustered with the non-Indian lineage (cosmopolitan genotype 4a), which was not recorded from the study area earlier. The time to most common recent ancestor (TMRCA) of these sequences was 7.4 years old, with the highest posterior density (HPD) of 3.5-12.2 years, indicating that this new lineage emerged during the year 2014. This is the first report on the DENV incrimination in both Ae. aegypti and Ae. albopictus mosquitoes collected from Bhopal, Central India. Conclusion: The observed emergence of the non-Indian lineage of DENV-2 in Bhopal, which again is a first report from the area, coincides with the gradual increase in DENV cases in Bhopal since 2014. This study emphasizes the importance of DENV surveillance and risk assessment in this strategically important part of the country to decipher its outbreak and severe disease-causing potential.

11.
Microorganisms ; 10(2)2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35208787

RESUMO

Blood feeding is an important behavior of Aedes aegypti, a dominant arboviral disease vector, as it can establish and transmit viruses to humans. Bacteria associated with the mosquito gut can modulate the biological characteristics and behavior of disease vectors. In this study, we characterized the gut microbiota composition of human-blood-fed (HF), non-human-blood-fed (NHF) and non-fed (NF) field-collected Ae. aegypti mosquitoes, using a 16S metagenomic approach, to assess any association of bacterial taxa with the blood-feeding behavior of Ae. aegypti. A significant difference in the microbiota composition between the HF and NF mosquito group was observed. A significant association was observed in the relative abundance of families Rhodobacteraceae, Neisseriaceae and Dermacoccaceae in the HF group in contrast to NF and NHF Ae. aegypti mosquitoes, respectively. At the class level, two classes (Rhodobacterales and Neisseriales) were found to be in higher abundance in the HF mosquitoes compared to a single class of bacteria (Caulobacterales) in the NF mosquitoes. These results show that human-blood feeding may change the gut microbiota in wild Ae. aegypti populations. More research is needed to determine how changes in the midgut bacterial communities in response to human-blood-feeding affect the vectorial capacity of Ae. aegypti.

12.
Prostate ; 71(13): 1441-54, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21321980

RESUMO

BACKGROUND: The skeleton is the most common site of prostate cancer metastasis, which often results in osteoblastic lesions. The role of transforming growth factor-beta (TGFß) signaling in prostate cancer-induced osteoblastic metastasis is not clear. We investigated the role of TGFß signaling in prostate cancer-induced bone metastasis using a novel human prostate cancer cell line, PacMetUT1. METHODS: We injected PacMetUT1/Luc-GFP cells in male nude mice by intracardiac and intratibia injections and then investigated the effect of TGFß signaling abrogation on osteoblastic tumor growth and incidence in vivo by using fluorescence and bioluminescence imaging analysis and quantifying bone and tumor volume by histomorphometry analysis. Osteoclasts were counted using TRAP assay. RESULTS: Osteoblastic bone metastasis in skull, rib, and femur was detected after 10-16 weeks of intracardiac injection of the PacMetUT1 cells. Stable knockdown of TGFß1 with an shRNA resulted in decreased tumor incidence and bone formation when the cells were directly injected into the tibiae. Systemic administration of either a small inhibitor of TGFß type I receptor kinase or a pan TGFß binding protein (BG(E) RII) also decreased bone tumor growth and osteoblastic bone formation in vivo after 7 weeks of treatment. CONCLUSIONS: Our results for the first time indicate that blockade of TGFß signaling in the PacMetUT1 model significantly inhibits osteoblastic bone formation and tumor incidence. Thus, TGFß signaling pathway may be a viable target for the prevention and treatment of prostate cancer-induced bone metastasis.


Assuntos
Neoplasias Ósseas/secundário , Osteoblastos/patologia , Neoplasias da Próstata/patologia , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Animais , Sequência de Bases , Neoplasias Ósseas/prevenção & controle , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Pulmonares/secundário , Masculino , Camundongos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta/fisiologia
13.
Molecules ; 16(9): 7256-66, 2011 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-21869753

RESUMO

Graphite oxide and graphene oxides have been used as solid catalysts for the synthesis of 5,5-dialkyldipyrromethanes and calix[4]pyrroles in organic and aqueous solutions at room temperature.


Assuntos
Calixarenos/síntese química , Grafite/química , Óxidos/química , Porfirinas/síntese química , Pirróis/síntese química , Acetona/química , Catálise , Cloreto de Metileno/química , Solventes/química , Tensoativos/química , Suspensões
14.
Curr Med Chem ; 27(35): 6015-6056, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30585536

RESUMO

Nanotechnology offers promising tools in interdisciplinary research areas and getting an upsurge of interest in cancer therapeutics. Organic nanomaterials and inorganic nanomaterials bring revolutionary advancement in cancer eradication process. Oncology is achieving new heights under nano technological platform by expediting chemotherapy, radiotherapy, photo thermodynamic therapy, bio imaging and gene therapy. Various nanovectors have been developed for targeted therapy which acts as "Nano-bullets" for tumor cells selectively. Recently combinational therapies are catching more attention due to their enhanced effect leading towards the use of combined organicinorganic nano platforms. The current review covers organic, inorganic and their hybrid nanomaterials for various therapeutic action. The technological aspect of this review emphasizes on the use of inorganic-organic hybrids and combinational therapies for better results and also explores the future opportunities in this field.


Assuntos
Nanoestruturas , Neoplasias , Terapia Combinada , Diagnóstico por Imagem , Portadores de Fármacos/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico
15.
Biochim Biophys Acta Gene Regul Mech ; 1863(10): 194624, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32798738

RESUMO

Chromatin modulation provides a key checkpoint for controlling cell cycle regulated gene networks. The replicative canonical histone genes are one such gene family under tight regulation during cell division. These genes are most highly expressed during S phase when histones are needed to chromatinize the new DNA template. While this fact has been known for a while, limited knowledge exists about the specific chromatin regulators controlling their temporal expression during cell cycle. Since histones and their associated mutations are emerging as major players in diseases such as cancer, identifying the chromatin factors modulating their expression is critical. The histone lysine tri-demethylase KDM4A is regulated over cell cycle and plays a direct role in DNA replication timing, site-specific rereplication, and DNA amplifications during S phase. Here, we establish an unappreciated role for the catalytically active KDM4A in directly regulating canonical replicative histone gene networks during cell cycle. Of interest, we further demonstrate that KDM4A interacts with proteins controlling histone expression and RNA processing (i.e., hnRNPUL1 and FUS/TLS). Together, this study provides a new function for KDM4A in modulating canonical histone gene expression.


Assuntos
Replicação do DNA , Regulação da Expressão Gênica , Histonas/genética , Histona Desmetilases com o Domínio Jumonji/genética , Catálise , Epigênese Genética , Perfilação da Expressão Gênica , Histonas/metabolismo , Humanos , Transcrição Gênica
16.
Cancer Discov ; 10(2): 306-325, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31776131

RESUMO

Acquired chromosomal DNA copy gains are a feature of many tumors; however, the mechanisms that underpin oncogene amplification are poorly understood. Recent studies have begun to uncover the importance of epigenetic states and histone lysine methyltransferases (KMT) and demethylases (KDM) in regulating transient site-specific DNA copy-number gains (TSSG). In this study, we reveal a critical interplay between a myriad of lysine methyltransferases and demethylases in modulating H3K4/9/27 methylation balance to control extrachromosomal amplification of the EGFR oncogene. This study further establishes that cellular signals (hypoxia and EGF) are able to directly promote EGFR amplification through modulation of the enzymes controlling EGFR copy gains. Moreover, we demonstrate that chemical inhibitors targeting specific KMTs and KDMs are able to promote or block extrachromosomal EGFR amplification, which identifies potential therapeutic strategies for controlling EGFR copy-number heterogeneity in cancer, and, in turn, drug response. SIGNIFICANCE: This study identifies a network of epigenetic factors and cellular signals that directly control EGFR DNA amplification. We demonstrate that chemical inhibitors targeting enzymes controlling this amplification can be used to rheostat EGFR copy number, which uncovers therapeutic opportunities for controlling EGFR DNA amplification heterogeneity and the associated drug response.This article is highlighted in the In This Issue feature, p. 161.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Metilação de DNA/genética , Histonas/metabolismo , Neoplasias/genética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Hipóxia Celular/genética , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Amplificação de Genes/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/antagonistas & inibidores , Histona Desmetilases com o Domínio Jumonji/metabolismo , Lisina/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
17.
Curr Top Med Chem ; 17(19): 2199-2214, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28137229

RESUMO

BACKGROUND: The viruses responsible for mosquito-borne diseases are on an exploring mode, expanding their horizon, adapting to the situation and comfortably making their presence felt globally, from South Africa to Asia, Europe and United States. The current global scenario and recent documentations indicate towards the real monsters, outbreak of Zika, dengue and chikungunya viruses. Zika, dengue and chikungunya viruses are positive sense single-stranded RNA arbovirus and so their initial symptoms are almost 80% similar and all three are spread by mosquitos which bite during the day. Zika virus may damage brain by targeting the neuron cells in babies, and thereby it is very perilous to pregnant women. Dangerous Type: A less common but highly dangerous type of dengue is one which causes haemorrhagic fever and shock syndrome which are lethal. Chikungunya is not as lethal as Zika and dengue are, but it triggers joints pain which could last for months and even for years. CONCLUSION: The vaccines against Zika, dengue and chikungunya viruses are at different stages of development. The challenges associated with the epidemic wave of Zika, dengue and chikungunya viruses have been explained and the current status of drug/ vaccine development against these viruses has been reviewed.


Assuntos
Febre de Chikungunya/transmissão , Dengue/transmissão , Surtos de Doenças , Mosquitos Vetores/virologia , Infecção por Zika virus/transmissão , Animais , Febre de Chikungunya/epidemiologia , Dengue/epidemiologia , Feminino , Humanos , Recém-Nascido , Gravidez , Infecção por Zika virus/epidemiologia
19.
Pathog Glob Health ; 111(4): 186-194, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28549390

RESUMO

The spread of P. falciparum resistant strain has led to a significant resurgence of malaria morbidity and mortality. The current cornerstone in malaria treatment in India is Artemisinin based Combination (Artesunate + Sulphadoxine-Pyrimethamine) Therapy (ACT) for treatment of uncomplicated P. falciparum malaria since 2010. In the present study we assessed the therapeutic efficacy of ACT and molecular monitoring of antimalarial resistance. Therapeutic efficacy was determined by in vivo method using 28 days follow-up. Molecular genotyping of dihydrofolate reductase (dhfr), dihydropteroate synthase (dhps) and kelch13 genes were analyzed. msp-1 and msp-2 genotyping were used to differentiate recrudescence. Therapeutic efficacy of ACT was determined in 237 patients over the three year period. Most of the patients showed adequate clinical and parasitological response (99.6%). Molecular study revealed that 72% parasites were of mutant genotype (27.2% single mutants, 43.5% double mutants and 1.3% triple mutants) for pfdhfr while pfdhps showed 78.2% wild type alleles and 21.8% mutants (18.1% single mutants and 3.7% double mutants). Analysis of total 135 samples revealed mutation in k13 gene along with non-synonymous single mutation at codon M579T (1.5%) and double mutations at codon M579T & N657H in 37%. ACT remains effective for the treatment of uncomplicated P. falciparum malaria in Madhya Pradesh, Central India. However, increasing mutation in pfdhfr (particularly triple mutations) and pfdhps may reduce susceptibility to partner drug SP and mutation in k13 propeller gene, highlighting the need for continuous monitoring of the efficacy of ACT.


Assuntos
Antimaláricos/farmacologia , Artemisininas/farmacologia , Resistência a Medicamentos , Plasmodium falciparum/efeitos dos fármacos , Pirimetamina/farmacologia , Sulfadoxina/farmacologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Artesunato , Criança , Pré-Escolar , Combinação de Medicamentos , Monitoramento Epidemiológico , Feminino , Genes de Protozoários , Genótipo , Técnicas de Genotipagem , Humanos , Índia , Lactente , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum/genética , Plasmodium falciparum/isolamento & purificação , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Resultado do Tratamento , Adulto Jovem
20.
Mol Cell Biol ; 36(7): 1050-63, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26755558

RESUMO

Chromosomal copy number changes are frequently associated with harmful consequences and are thought of as an underlying mechanism for the development of diseases. However, changes in copy number are observed during development and occur during normal biological processes. In this review, we highlight the causes and consequences of copy number changes in normal physiologic processes as well as cover their associations with cancer and acquired drug resistance. We discuss the permanent and transient nature of copy number gains and relate these observations to a new mechanism driving transient site-specific copy gains (TSSGs). Finally, we discuss implications of TSSGs in generating intratumoral heterogeneity and tumor evolution and how TSSGs can influence the therapeutic response in cancer.


Assuntos
Aberrações Cromossômicas , Dosagem de Genes , Adaptação Biológica , Animais , Resistência a Medicamentos/genética , Heterogeneidade Genética , Variação Estrutural do Genoma , Humanos , Neoplasias/genética
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