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1.
Parasitol Res ; 120(6): 2047-2056, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33893552

RESUMO

Nematodes of the genus Physaloptera are globally distributed and infect a multitude of hosts. Their life cycle involves orthopterans and coleopterans as intermediate hosts. The morphological characters alone are inadequate to detect and differentiate Physaloptera spp. from its congeners. Moreover, molecular studies are limited to compare them precisely. The present communication reports the first molecular phylogenetic characterization of feline Physaloptera spp. from India based on mitochondrial cytochrome c oxidase subunit 1 (COX1) and small subunit ribosomal DNA (18S rDNA). The nematodes were first isolated from the stomach of adult stray cats during necropsy examination. Based on the gross and microscopic characters, the worms were identified as P. praeputialis. Morphological identification was further confirmed through PCR targeting the barcode region of the mitochondrial cytochrome c oxidase subunit I (MT-COI) gene, using nematode-specific primers cocktail followed by species specific primers targeting partial COX1 and 18S rRNA genes. Generated sequences were submitted in NCBI GenBank (MW517846, MW410927, MW411349), and phylogenetic trees were constructed using the maximum likelihood method. When compared with other sequences of Physaloptera species across the globe, the present isolates showed 85.6-97.7% and 97.3-99% nucleotide homology based on COX1 and 18S rRNA gene, respectively. BLASTn analysis revealed a strong identity to other Physaloptera spp., and the phylogenetic tree placed all Physaloptera spp. in the same cluster. This study again indicates the usefulness of molecular techniques to substantiate the identity of species that may lack adequate descriptions and impart new insight for the potentially overlooked significance of P. praeputialis infections in felines.


Assuntos
Gatos/parasitologia , Filogenia , Spiruroidea/classificação , Animais , DNA de Helmintos/genética , DNA Ribossômico/genética , Genes Mitocondriais/genética , Índia , Análise de Sequência de DNA , Especificidade da Espécie , Spiruroidea/genética , Spiruroidea/isolamento & purificação
2.
Parasitol Res ; 119(2): 473-481, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31897790

RESUMO

Equine ocular setariasis arising mainly from ectopic infestation of Setaria digitata is a common vision impairing ophthalmic disease in India, and the identification of this filarial nematode is based solely on morphology. However, morphological characters alone are inadequate to detect and differentiate S. digitata from its congeners. The present communication reports the first phylogenetic characterization of equine S. digitata from India based on sequences derived from the mitochondrial cytochrome c oxidase subunit 1 (COI), the mitochondrial small subunit ribosomal DNA (12S rDNA), and the nuclear internal transcribed spacer 2 (ITS2). Three isolates were characterized for each gene, and respective sequences were submitted to NCBI database (MN078131, MN078132, and MN095798). The sequences were also compared with the other related sequences available from PubMed around the globe, and phylogenetic analysis was carried out in conjunction with nucleotide homologies. There was no intraspecific variation among the Indian isolates. The phylogenetic analysis of S. digitata, inferred from these genes, showed that the isolate sequences obtained from different host species created a separate monophyletic clade within the genus Setaria with minor sequence variations revealing similar molecular characteristics of S. digitata isolates throughout the globe. In addition, the studied Indian isolates were found closer to Sri Lankan isolates. The S. digitata and S. labiatopapillosa appeared as sister species.


Assuntos
Oftalmopatias/veterinária , Filarioidea/isolamento & purificação , Doenças dos Cavalos/parasitologia , Cavalos/parasitologia , Setaria (Nematoide)/isolamento & purificação , Setaríase/parasitologia , Animais , DNA Intergênico/genética , DNA Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Oftalmopatias/parasitologia , Filarioidea/genética , Índia , Filogenia , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico/genética , Análise de Sequência de DNA , Setaria (Nematoide)/genética
3.
Clin Radiol ; 74(12): 978.e15-978.e27, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31594559

RESUMO

Most soft-tissue lumps in the hand are benign, with ganglions being the commonest, but in the thenar region, solid soft-tissue masses are more common than a ganglion. In this review, we focus on soft-tissue lesions (neoplastic and non-neoplastic) presenting as a palpable lump in this region. A specific diagnosis can often be reached using ultrasonography and/or magnetic resonance imaging. Most of these lesions are managed in local hospitals or primary care, whereas some are referred to specialist centres. This review article will help both general and musculoskeletal radiologists to diagnose and characterise these lesions, provide a guide for further imaging, and provide an insight into imaging features that may need specific investigations such as core biopsy, tertiary referral, and further review at multidisciplinary meetings.


Assuntos
Mãos/diagnóstico por imagem , Diagnóstico Diferencial , Cistos Glanglionares/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neoplasias de Tecidos Moles/diagnóstico por imagem , Ultrassonografia
4.
Clin Radiol ; 74(6): 450-455, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30952360

RESUMO

AIM: To assess the current practice of scaphoid fracture imaging (where initial scaphoid radiographs are normal) in the UK. MATERIALS AND METHODS: A survey monkey questionnaire was sent to 140 eligible NHS trusts derived from the NHS England database following exclusion of all non-acute and specialist centres. Four questions were asked regarding the provision of magnetic resonance imaging (MRI) for radiographically occult scaphoid fractures, time to MRI, number of departmental MRI scanners, and alternative imaging offered. RESULTS: Responses were received from 74 trusts (53%). Thirty-eight offered MRI as a first-line test in plain-film occult scaphoid injury, 25 preferred computed tomography (CT), and 11 opted for repeat plain radiographs. Of the 38 trusts who offered MRI, 26 provided this within 1 week; the rest within 2 weeks. No trends were identified based on the size of the hospital or its geographical location. Statistical analysis of the data revealed no significant relationship between the number of MRI scanners and the provision of MRI, nor between the numbers of MRI scanners and the time to MRI. CONCLUSIONS: MRI has been recognised in the literature as a highly specific, highly sensitive, and cost-effective tool, yet only 51% of trusts provide this service in the UK. For those who cannot offer MRI first-line, CT remains a very accurate and reliable alternative.


Assuntos
Fraturas Ósseas/diagnóstico por imagem , Imageamento por Ressonância Magnética/estatística & dados numéricos , Radiografia/estatística & dados numéricos , Osso Escafoide/diagnóstico por imagem , Osso Escafoide/lesões , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Humanos , Imageamento por Ressonância Magnética/métodos , Radiografia/métodos , Inquéritos e Questionários , Tomografia Computadorizada por Raios X/métodos , Reino Unido
5.
BMC Cancer ; 18(1): 1172, 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30477459

RESUMO

BACKGROUND: Germline mutations in BAP1 have been associated with BAP1-Tumor Predisposition Syndrome (BAP1-TPDS), a predisposition to multiple tumors within a family that includes uveal melanoma (UM), cutaneous melanoma, malignant mesothelioma and renal cell carcinoma. Alternatively, somatic mutations in BAP1 in UM have been associated with high risk for metastasis. In this study, we compare the risk of metastasis in UM that carry germline versus somatic BAP1 mutations and mutation-negative tumors. METHODS: DNA extracted from 142 UM and matched blood samples was sequenced using Sanger or next generation sequencing to identify BAP1 gene mutations. RESULTS: Eleven of 142 UM (8%) carried germline BAP1 mutations, 43 (30%) had somatic mutations, and 88 (62%) were mutation-negative. All BAP1 mutations identified in blood samples were also present in the matched UM. There were 52 unique mutations in 54 tumors. All were pathogenic or likely pathogenic. A comparison of tumors carrying somatic vs. germline mutations, or no mutations, showed a higher frequency of metastasis in tumors carrying somatic mutations: 74% vs. 36%, P=0.03 and 74% vs. 26% P<0.001, respectively. Tumors with a somatic mutation compared to mutation-negative had an older age of diagnosis of (61.8 vs. 52.2 years, P=0.002), and shorter time to metastasis (16 vs. 26 months, P=0.04). Kaplan-Meier analysis further showed that tumors with somatic (vs. germline) mutations demonstrated a greater metastatic risk (P=0.03). Cox multivariate analysis showed in addition to chromosome-3 monosomy and larger tumor diameter, the presence of BAP1 somatic, but not germline mutations, was significantly associated with risk of metastasis(P=0.02). Personal or family history of BAP1-TPDS was available for 79 of the cases. All eight cases with germline mutations reported a history of BAP1-TPDS, which was significantly greater than what was observed in cases with somatic mutations (10 of 23, P=0.009) or mutation-negative cases (11 of 48, P<0.001). CONCLUSIONS: Defining germline vs. somatic nature of BAP1 mutations in UM can inform the individual about both the risk of metastasis, and the time to metastasis, which are critically important outcomes for the individual. This information can also change the cascade screening and surveillance of family members.


Assuntos
Mutação em Linhagem Germinativa , Melanoma/genética , Melanoma/patologia , Mutação , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Neoplasias Uveais/genética , Neoplasias Uveais/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 3 , Variações do Número de Cópias de DNA , Feminino , Predisposição Genética para Doença , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/mortalidade , Pessoa de Meia-Idade , Metástase Neoplásica , Modelos de Riscos Proporcionais , Neoplasias Uveais/mortalidade , Adulto Jovem
6.
Haemophilia ; 20(6): e384-91, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25196590

RESUMO

The paper describes the experience of the Genetic Diagnostic Laboratory in prenatal testing for haemophilia A, an X-linked recessive disease caused by mutations in the F8 gene. Knowledge of a familial mutation prior to pregnancy can benefit prenatal diagnosis and decrease wait time for molecular testing during pregnancy. This is a retrospective review of a series of pregnant women who pursued F8 gene testing from December 1997 through May 2012, highlighting three cases, which demonstrate the technical complexities of analysis and the implications of not knowing carrier status prior to pregnancy. Mutations of the F8 gene were detected in affected males, obligate female carriers and suspected female carriers by DNA sequencing, inverse-PCR, qRT-PCR, Southern blot and exonic dosage analysis. The same methods were used to analyse prenatal samples from obligate or suspected female carriers upon request. Maternal cell contamination studies were performed for all prenatal samples analysed. Ninety-nine women pursued F8 testing during pregnancy, either for carrier status alone or carrier status and prenatal diagnosis. Ninety-one women (91%) requested carrier testing because they did not know their F8 mutation carrier status prior to pregnancy. Eight women requested prenatal diagnosis only, and only 4 of these were aware of their mutation status. Thirty-seven individuals were found to be mutation carriers. Forty-two prenatal samples were received for prenatal diagnosis. In total 21 foetuses were identified as mutation carriers. Mutation detection was complex and increased the turnaround time in some cases. Only four of 99 women who submitted samples for F8 testing were aware of their F8 mutation status prior to pregnancy. Knowledge of F8 mutation status prior to pregnancy allows for efficient prenatal diagnosis, when desired. Thus, preconception genetic counselling is required to inform patients of the available options and the complex and time-consuming nature of F8 testing.


Assuntos
Hemofilia A/diagnóstico , Hemofilia A/genética , Diagnóstico Pré-Natal , Adulto , Bases de Dados Genéticas , Fator VIII/genética , Feminino , Testes Genéticos , Humanos , Masculino , Mutação , Gravidez , Diagnóstico Pré-Natal/métodos , Estudos Retrospectivos
7.
Haemophilia ; 20(2): e136-43, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24533955

RESUMO

Haemophilia A and B are rare X-lined hemorrhagic disorders that typically affect men. Women are usually asymptomatic carriers, but may be symptomatic and, rarely, also express severe (factor VIII (FVIII) or factor IX (FIX) <0.01 U mL(-1)) or moderately severe (FVIII/FIX 0.01-0.05 U mL(-1)) phenotypes. However, data on clinical manifestations, genotype and the psychosocial ramifications of illness in severely affected females remain anecdotal. A national multi-centre retrospective study was conducted to collect a comprehensive data set on affected US girls and women, and to compare clinical observations to previously published information on haemophilic males of comparable severity and mildly affected haemophilic females. Twenty-two severe/moderate haemophilia A/B subjects were characterized with respect to clinical manifestations and disease complications; genetic determinants of phenotypic severity; and health-related quality of life (HR-QoL). Clinical data were compared as previously indicated. Female patients were older than male patients at diagnosis, but similarly experienced joint haemorrhage, disease- and treatment-related complications and access to treatment. Gynaecological and obstetrical bleeding was unexpectedly infrequent. F8 or F9 mutations, accompanied by extremely skewed X-chromosome inactivation pattern (XIP), were primary determinants of severity. HR-QoL was diminished by arthropathy and viral infection. Using systematic case verification of participants in a national surveillance registry, this study elucidated the genetics, clinical phenotype and quality of life issues in female patients with severe/moderate haemophilia. An ongoing international case-controlled study will further evaluate these observations. Novel mechanistic questions are raised about the relationship between XIP and both age and tissue-specific FVIII and FIX expression.


Assuntos
Hemofilia A/epidemiologia , Hemofilia B/epidemiologia , Fenótipo , Análise Citogenética , Fator IX/genética , Fator VIII/genética , Feminino , Hemofilia A/complicações , Hemofilia A/diagnóstico , Hemofilia A/tratamento farmacológico , Hemofilia B/complicações , Hemofilia B/diagnóstico , Hemofilia B/tratamento farmacológico , Humanos , Masculino , Mutação , Qualidade de Vida , Sistema de Registros , Fatores de Risco , Índice de Gravidade de Doença , Estados Unidos/epidemiologia
9.
Eur Rev Med Pharmacol Sci ; 17(6): 802-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23609364

RESUMO

INTRODUCTION: Respiratory tract infections due to viral etiology were studied with an objective to identify and compare the pathogens between Hospital Indoor and Outdoor Units. MATERIALS AND METHODS: A hospital-based cross-sectional study was conducted among children below 12 years over a period of one year. The throat and nasal swabs were collected from both the Units and screened for viral infections by real time RT-PCR technique. RESULTS: Out of 880 samples collected, 87% and 13% were from outdoor and indoor Department with total viral positivity rate of 30% and 25% respectively. Influenza B virus (IBV) (n=126, 16%) was more prevalent in Outdoor Unit, whereas respiratory syncytial virus (RSV) (n=18, 16%) among indoor admitted cases. The multinomial logistic regression analysis revealed that both RSV and Influenza viruses were predominant in children of pre-school age groups < 5 years. In the year 2010-11, the prevalence of human metapneumovirus (HMPV) was low. The pandemic influenza A virus (pH1N1/2009) accounted for 4% (n=29) and 0.8% (n=1) cases among Outdoor and Indoor Units respectively. CONCLUSIONS: The Outdoor Department outnumbered the Indoor Unit in terms of patient attendees and the rate of viral infections. An effective vaccination and continuous surveillance program is the need of the hour.


Assuntos
Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Pré-Escolar , Estudos Transversais , Feminino , Hospitalização , Humanos , Índia/epidemiologia , Lactente , Masculino , Pacientes Ambulatoriais
10.
Nat Genet ; 2(1): 66-74, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1303253

RESUMO

Patients with glucocorticoid-remediable aldosteronism (GRA) from 12 kindreds possess chimaeric gene duplications arising from unequal crossing-over, fusing regulatory sequences of steroid 11 beta-hydroxylase to coding sequences of aldosterone synthase. These chimaeric genes are specific for GRA and explain the biochemistry, physiology and genetics of this form of hypertension. Sites of crossing over range from intron 2 to intron 4. Most mutations have arisen independently from either sister or non-sister chromatid exchange between these genes, which are only 45 kilobases apart. The possibility of a susceptibility allele for GRA of Irish origin is suggested. These findings indicate the utility of a direct genetic test for this disorder.


Assuntos
Quimera/genética , Sistema Enzimático do Citocromo P-450/genética , Hipertensão/genética , Família Multigênica , Esteroide Hidroxilases/genética , Alelos , Sequência de Bases , Troca Genética , Citocromo P-450 CYP11B2 , DNA/genética , Feminino , Expressão Gênica , Haplótipos/genética , Humanos , Desequilíbrio de Ligação , Masculino , Dados de Sequência Molecular , Linhagem , Esteroide 11-beta-Hidroxilase/genética
11.
Med Phys ; 39(11): 6652-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23127059

RESUMO

PURPOSE: The authors have developed a method to enable cerebral perfusion CT imaging using C-arm based conebeam CT (CBCT). This allows intraprocedural monitoring of brain perfusion during treatment of stroke. Briefly, the technique consists of acquiring multiple scans (each scan comprised of six sweeps) acquired at different time delays with respect to the start of the x-ray contrast agent injection. The projections are then reconstructed into angular blocks and interpolated at desired time points. The authors have previously demonstrated its feasibility in vivo using an animal model. In this paper, the authors describe an in vitro technique to evaluate the accuracy of their method for measuring the relevant temporal signals. METHODS: The authors' evaluation method is based on the concept that any temporal signal can be represented by a Fourier series of weighted sinusoids. A sinusoidal phantom was developed by varying the concentration of iodine as successive steps of a sine wave. Each step corresponding to a different dilution of iodine contrast solution contained in partitions along a cylinder. By translating the phantom along the axis at different velocities, sinusoidal signals at different frequencies were generated. Using their image acquisition and reconstruction algorithm, these sinusoidal signals were imaged with a C-arm system and the 3D volumes were reconstructed. The average value in a slice was plotted as a function of time. The phantom was also imaged using a clinical CT system with 0.5 s rotation. C-arm CBCT results using 6, 3, 2, and 1 scan sequences were compared to those obtained using CT. Data were compared for linear velocities of the phantom ranging from 0.6 to 1 cm∕s. This covers the temporal frequencies up to 0.16 Hz corresponding to a frequency range within which 99% of the spectral energy for all temporal signals in cerebral perfusion imaging is contained. RESULTS: The errors in measurement of temporal frequencies are mostly below 2% for all multiscan sequences. For single scan sequences, the errors increase sharply beyond 0.10 Hz. The amplitude errors increase with frequency and with decrease in the number of scans used. CONCLUSIONS: Our multiscan perfusion CT approach allows low errors in signal frequency measurement. Increasing the number of scans reduces the amplitude errors. A two-scan sequence appears to offer the best compromise between accuracy and the associated total x-ray and iodine dose.


Assuntos
Encéfalo/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Imagem de Perfusão/métodos , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Sensibilidade e Especificidade
12.
J Med Genet ; 48(2): 73-87, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19553198

RESUMO

BACKGROUND: HHT is an autosomal dominant disease with an estimated prevalence of at least 1/5000 which can frequently be complicated by the presence of clinically significant arteriovenous malformations in the brain, lung, gastrointestinal tract and liver. HHT is under-diagnosed and families may be unaware of the available screening and treatment, leading to unnecessary stroke and life-threatening hemorrhage in children and adults. OBJECTIVE: The goal of this international HHT guidelines process was to develop evidence-informed consensus guidelines regarding the diagnosis of HHT and the prevention of HHT-related complications and treatment of symptomatic disease. METHODS: The overall guidelines process was developed using the AGREE framework, using a systematic search strategy and literature retrieval with incorporation of expert evidence in a structured consensus process where published literature was lacking. The Guidelines Working Group included experts (clinical and genetic) from eleven countries, in all aspects of HHT, guidelines methodologists, health care workers, health care administrators, HHT clinic staff, medical trainees, patient advocacy representatives and patients with HHT. The Working Group determined clinically relevant questions during the pre-conference process. The literature search was conducted using the OVID MEDLINE database, from 1966 to October 2006. The Working Group subsequently convened at the Guidelines Conference to partake in a structured consensus process using the evidence tables generated from the systematic searches. RESULTS: The outcome of the conference was the generation of 33 recommendations for the diagnosis and management of HHT, with at least 80% agreement amongst the expert panel for 30 of the 33 recommendations.


Assuntos
Receptores de Activinas Tipo II/genética , Antígenos CD/genética , Epistaxe/terapia , Hemorragia Gastrointestinal/patologia , Receptores de Superfície Celular/genética , Telangiectasia Hemorrágica Hereditária/diagnóstico , Malformações Vasculares/patologia , Adulto , Criança , Detecção Precoce de Câncer , Endoglina , Epistaxe/patologia , Testes Genéticos , Humanos , Imageamento por Ressonância Magnética , Mutação/genética , Proteína Smad4/genética , Telangiectasia Hemorrágica Hereditária/genética , Telangiectasia Hemorrágica Hereditária/patologia
13.
Environ Monit Assess ; 184(1): 251-63, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21400241

RESUMO

On-site sanitation has emerged as a preferred mode of sanitation in cities experiencing rapid urbanization due to the high cost involved in off-site sanitation which requires conventional sewerages. However, this practice has put severe stress on groundwater especially its quality. Under the above backdrop, a study has been undertaken to investigate the impact of on-site sanitation on quality of groundwater sources in two mega cities namely Indore and Kolkata which are situated in two different geological settings. The parameters for the studies are distance of groundwater source from place of sanitation, effect of summer and monsoon seasons, local hydro-geological conditions, and physico-chemical parameters. NO(3) and fecal coliform concentrations are considered as main indexes of pollution in water. Out of many conclusions which can be made from this studies, one major conclusion is about the influence of on-site sanitation on groundwater quality is minimal in Kolkata, whereas it is significant in Indore. This difference is due to the difference in hydrogeological parameters of these two cities, Kolkata being on alluvium quaternary and Indore being on Deccan trap of Cretaceous to Paleogene age.


Assuntos
Monitoramento Ambiental/métodos , Fenômenos Geológicos , Água Subterrânea/análise , Poluentes da Água/química , Poluição Química da Água/prevenção & controle , Índia , Nitratos/química , Estações do Ano , Solo/química , Inquéritos e Questionários
14.
Phys Biol ; 8(5): 055008, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21832803

RESUMO

On top of the many external perturbations, cellular oscillators also face intrinsic perturbations due the randomness of chemical kinetics. Biomolecular oscillators, distinct in their parameter sets or distinct in their architecture, show different resilience with respect to such intrinsic perturbations. Assessing this resilience can be done by ensemble stochastic simulations. These are computationally costly and do not permit further insights into the mechanistic cause of the observed resilience. For reaction systems operating at a steady state, the linear noise approximation (LNA) can be used to determine the effect of molecular noise. Here we show that methods based on LNA fail for oscillatory systems and we propose an alternative ansatz. It yields an asymptotic expression for the phase diffusion coefficient of stochastic oscillators. Moreover, it allows us to single out the noise contribution of every reaction in an oscillatory system. We test the approach on the one-loop model of the Drosophila circadian clock. Our results are consistent with those obtained through stochastic simulations with a gain in computational efficiency of about three orders of magnitude.


Assuntos
Ritmo Circadiano/fisiologia , Animais , Drosophila/fisiologia , Modelos Biológicos , Processos Estocásticos
15.
Cell Death Differ ; 15(10): 1629-40, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18566607

RESUMO

In the post-genomic perspective, the quest of programmed cell death (PCD) mechanisms in kinetoplastid parasites lies in the identification and characterization of cell death executer proteins. Here, we show that baicalein (BLN), a potent topoisomerase IB inhibitor, generates an oxidative stress in the parasites leading to altered physiological and morphological parameters, which are characteristic of PCD. For the first time we elucidate that, caspase-independent activation of a novel effector molecule, endonuclease G (LdEndoG), mediates BLN-induced cell death. Functional characterization of LdEndoG identifies Flap endonuclease-1 (LdFEN-1) and LdTatD-like nuclease as other effector molecules. BLN treatment translocates LdEndoG from mitochondria to nucleus, where it forms separate complexes with LdFEN-1 and LdTatD to constitute a DNA 'degradesome' unique to these parasites. Conditional antisense knockdown of LdEndoG provides protection against PCD. This knowledge paves the path toward a better understanding of the PCD pathway in simpler systems, which could be exploited in anti-leishmanial chemotherapy.


Assuntos
Morte Celular/fisiologia , DNA/metabolismo , Desoxirribonucleases/metabolismo , Endodesoxirribonucleases/metabolismo , Endonucleases Flap/metabolismo , Flavanonas/metabolismo , Leishmania donovani/fisiologia , Algoritmos , Animais , Fragmentação do DNA , Desoxirribonucleases/genética , Endodesoxirribonucleases/genética , Ativação Enzimática , Inibidores Enzimáticos/metabolismo , Endonucleases Flap/genética , Leishmania donovani/citologia , Potencial da Membrana Mitocondrial/fisiologia , Complexos Multienzimáticos/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais/fisiologia
16.
In Vivo ; 23(3): 401-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19454505

RESUMO

Glutathione (GSH), an important component of the phase II detoxification system, plays a major role in storage, metabolism and transport of metals across the cell membrane. The role of copper, its metabolism and storage in living systems is not completely understood. Copper plays an important role in a number of physiological processes, e.g. several growth and transcription factors require copper for activity. In the present investigation, we focused on copper (II) (N-2-hydroxyacetophenone) glycinate (CuNG), a novel in vitro and in vivo resistance modifying agent. A conjugate of GSH and CuNG was detected in vivo in mice and was characterized by spectroscopic studies. Based on UV, IR, proton NMR and elemental analyses, the chemical structure of the conjugate was elucidated. By means of atomic absorption data, the distribution and metabolism of CuNG is described.


Assuntos
Cobre/metabolismo , Glutationa/metabolismo , Animais , Cromatografia Líquida , Cobre/química , Glutationa/química , Masculino , Camundongos , Modelos Moleculares , Análise Espectral/métodos
17.
Cell Death Differ ; 14(2): 358-67, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16841091

RESUMO

Protein kinase C (PKC) is an important constituent of the signaling pathways involved in apoptosis. We report here that like staurosporine, withaferin A is a potent inhibitor of PKC. In Leishmania donovani, the inhibition of PKC by withaferin A causes depolarization of DeltaPsim and generates ROS inside cells. Loss of DeltaPsim leads to the release of cytochrome c into the cytosol and subsequently activates caspase-like proteases and oligonucleosomal DNA cleavage. Moreover, in treated cells, oxidative DNA lesions facilitate the stabilization of topoisomerase I-mediated cleavable complexes, which also contribute to DNA fragmentation. However, withaferin A and staurosporine cannot induce cleavable complex formation in vitro with recombinant topoisomerase I nor with nuclear extracts from control cells. Taken together, our results indicate that inhibition of PKC by withaferin A is a central event for the induction of apoptosis and that the stabilization of topoisomerase I-DNA complex is necessary to amplify apoptotic process.


Assuntos
Apoptose/efeitos dos fármacos , DNA Topoisomerases Tipo I/metabolismo , DNA de Protozoário/metabolismo , Ergosterol/análogos & derivados , Leishmania donovani/citologia , Leishmania donovani/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Animais , Caspases/metabolismo , Catálise/efeitos dos fármacos , Citocromos c/metabolismo , Citosol/efeitos dos fármacos , Clivagem do DNA/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Ergosterol/química , Ergosterol/farmacologia , Glutationa/metabolismo , Leishmania donovani/enzimologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteína Quinase C/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Espécies Reativas de Oxigênio/metabolismo , Estaurosporina/química , Estaurosporina/farmacologia , Vitanolídeos
18.
Indian J Med Res ; 127(2): 140-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18403791

RESUMO

BACKGROUND & OBJECTIVE: India has a high prevalence of HIV-1, hapatitis C and B virus (HCV and HBV) in the blood donors but has yet to implement nucleic acid testing (NAT) in blood screening. We undertook a multicentre evaluation of blood donor testing by NAT for simultaneous detection of HIV-1, HBV and HCV in a single tube and also to determine the feasibility of NAT implementation in India's low volume setting. METHODS: A total of 12,224 unlinked samples along with their serological results were obtained from representative eight blood banks in India and were individually manually tested by the Procleix Ultrio Assay (Chiron Corp. Emeryville, CA) for simultaneous detection of HIV-1, HCV, and HBV. RESULTS: Of the 12,224 samples tested, 209 (1.71%) were seroreactive. One hundred thirty three samples (1.09%) were reactive by Ultrio assay, 84 samples were seroreactive but NAT non reactive. There were eight NAT yield cases: 1 HIV, 1 HIV-HCV co-infection, and 6 HBV. INTERPRETATION & CONCLUSION: Our observed NAT yield for all three viruses was 1 in 1528 (0.065%). We estimate NAT could interdict 3272 infectious donations a year among our approximate 5 million annual donations.


Assuntos
Doadores de Sangue , Infecções por HIV/diagnóstico , HIV-1/metabolismo , Hepacivirus/metabolismo , Vírus da Hepatite B/metabolismo , Hepatite B/diagnóstico , Hepatite C/diagnóstico , Programas de Rastreamento/métodos , Técnicas de Amplificação de Ácido Nucleico/normas , RNA Viral/análise , Bancos de Sangue , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Hepatite B/epidemiologia , Hepatite B/transmissão , Hepatite C/epidemiologia , Hepatite C/transmissão , Humanos , Índia , Masculino , Testes Sorológicos/normas
19.
J Med Genet ; 43(10): 793-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16613914

RESUMO

BACKGROUND: Hereditary haemorrhagic telangiectasia (HHT) is an autosomal dominant disease exhibiting multifocal vascular telangiectases and arteriovenous malformations. The majority of cases are caused by mutations in either the endoglin (ENG) or activin receptor-like kinase 1 (ALK1, ACVRL1) genes; both members of the transforming growth factor (TGF)-beta pathway. Mutations in SMAD4, another TGF-beta pathway member, are seen in patients with the combined syndrome of juvenile polyposis (JP) and HHT (JP-HHT). METHODS: We sought to determine if HHT patients without any apparent history of JP, who were undergoing routine diagnostic testing, would have mutations in SMAD4. We tested 30 unrelated HHT patients, all of whom had been referred for DNA based testing for HHT and were found to be negative for mutations in ENG and ALK1. RESULTS: Three of these people harboured mutations in SMAD4, a rate of 10% (3/30). The SMAD4 mutations were similar to those found in other patients with the JP-HHT syndrome. CONCLUSIONS: The identification of SMAD4 mutations in HHT patients without prior diagnosis of JP has significant and immediate clinical implications, as these people are likely to be at risk of having JP-HHT with the associated increased risk of gastrointestinal cancer. We propose that routine DNA based testing for HHT should include SMAD4 for samples in which mutations in neither ENG nor ALK1 are identified. HHT patients with SMAD4 mutations should be screened for colonic and gastric polyps associated with JP.


Assuntos
Proteína Smad4/genética , Telangiectasia Hemorrágica Hereditária/genética , Receptores de Activinas Tipo II/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/genética , Análise Mutacional de DNA , Endoglina , Testes Genéticos , Humanos , Pólipos Intestinais/genética , Pessoa de Meia-Idade , Mutação , Pólipos/genética , Receptores de Superfície Celular/genética
20.
Cell Stress Chaperones ; 22(5): 675-684, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28265807

RESUMO

Heat stress proteins assist cellular proteins in the acquisition of native structure. The present research was conducted to study how thermo-tolerance is modulated by HSP90 and HSP70 gene polymorphism and its association with hemato-physio-biochemical parameters, supported by their expression profiles in Chokla, Magra, Marwari, and Madras Red sheep breeds. Least square analysis revealed significant effect (P < 0.05) of season and breed on all the physiological parameters, i.e., temperature, respiratory rate, and pulse rate (a.m. and p.m.), as well as hematological parameters like Hb, packed cell volume, total erythrocyte count (TEC), neutrophil/lymphocyte (N/L) ratio, and total leukocyte count (TLC). There was a significant influence (P < 0.05) of breed on biochemical parameters such as glucose, SGOT, phosphorous, triglyceride, and cholesterol. Eight fragments were amplified and sequenced in HSP90, and 70 genes and 13 single-nucleotide polymorphisms (SNPs) were identified. Tetra-primer amplification refractory mutation system PCR, PCR-RFLP, and allele-specific PCR genotyping protocols were developed for large-scale genotyping of five SNPs. A significant difference (P < 0.05) of rectal temperature (a.m.), respiratory rate (p.m.), triglyceride, and total protein was observed at SNP01; albumin at SNP2; pulse rate (p.m.) at SNP3; and rectal temperature (p.m.), pulse rate (p.m.), Hb (g/dL), and N/L ratio at SNP4 and TLC at SNP5. Gene expression analysis revealed higher expression in less adapted animals with Madras Red < Magra < Chokla < Marwari expression pattern [corrected]. Predominant allele was found to be superior in most of the SNPs (SNP1-4) indicating the selection acting in directional manner (positive selection). Finally, it is concluded that TACCA haplotype combination of SNP1-SNP2-SNP3-SNP4-SNP5 might be of some selection advantage for the identification of animals more adaptable to heat stress.


Assuntos
Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP90/genética , Alelos , Animais , Frequência do Gene , Estudos de Associação Genética , Genótipo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Haplótipos , Frequência Cardíaca/fisiologia , Índia , Análise dos Mínimos Quadrados , Polimorfismo de Nucleotídeo Único , Reto/fisiologia , Taxa Respiratória/fisiologia , Ovinos , Transcriptoma , Triglicerídeos/sangue
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