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1.
Parasite Immunol ; 40(7): e12535, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29745990

RESUMO

Leishmania donovani, the causative parasite of Visceral Leishmaniasis (VL), deviously manipulates host monocytes/macrophages to ensure its survival. Although monocytes/macrophages from patients with VL have demonstrated an impaired oxidative burst and antigen presentation, an unanswered yet pertinent question remains as to whether they are deactivated or alternatively activated. The significantly raised plasma levels of IL-4/IL-13 and IL-10 in VL patients suggested a microenvironment conducive for alternative activation of monocytes/macrophages. Accordingly, the classical markers for IL-4-driven monocytes/macrophages [M(IL-4)] were studied namely intramonocytic CD206+ , circulating CCL22 and CCL17, and were unchanged. Furthermore, the mRNA expression of Kruppel-like factor 4 (KLF4), peroxisome proliferator-activated receptors (PPAR)-γ and arginase-I (ARG-I) in peripheral blood mononuclear cells was unaltered. However, markers for IL-10-driven monocytes/macrophages [M(IL-10)], namely soluble CD163, intramonocytic IL-10, and circulating CXCL13 were significantly increased. Monocytes/macrophages of patients with VL demonstrated an increased expression of markers for M(IL-10), along with the absence of markers for M(IL-4). Taken together, in human VL, manipulation of these IL-10 polarized monocytes-macrophages may pave the way for improved therapeutic outcomes.


Assuntos
Interleucina-10/análise , Leishmania donovani/imunologia , Leishmaniose Visceral/imunologia , Adulto , Idoso , Feminino , Humanos , Fator 4 Semelhante a Kruppel , Leishmaniose Visceral/parasitologia , Leucócitos Mononucleares/imunologia , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Explosão Respiratória
2.
Artigo em Inglês | MEDLINE | ID: mdl-27653180

RESUMO

Recently, immunotherapy has yielded promising results in several cancer types. Contrary to the established classical chemotherapy-dosing paradigm, a maximum tolerated dose approach does not always produce better clinical outcomes for novel targeted therapies, as their efficacy is frequently robust at pharmacologically active doses below the maximum tolerated dose. Integrated safety and efficacy assessments are needed to inform clinical dose and trial design, and to support an early identification of potentially safe and efficacious combination treatments.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Simulação por Computador/tendências , Imunoterapia/tendências , Melanoma/tratamento farmacológico , Modelos Biológicos , Neoplasias Cutâneas/tratamento farmacológico , Antineoplásicos/administração & dosagem , Ensaios Clínicos Fase I como Assunto/estatística & dados numéricos , Humanos , Imunoterapia/métodos , Melanoma/diagnóstico , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Neoplasias Cutâneas/diagnóstico
3.
CPT Pharmacometrics Syst Pharmacol ; 6(1): 29-39, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27896938

RESUMO

Pembrolizumab is a potent immune-modulating antibody active in advanced melanoma, as demonstrated in the KEYNOTE-001, -002, and -006 studies. Longitudinal tumor size modeling was pursued to quantify exposure-response relationships for efficacy. A mixture model was first developed based on an initial dataset from KEYNOTE-001 to describe four patterns of tumor growth and shrinkage. For subsequent analyses, tumor size measurements were adequately described by a single consolidated model structure that captured continuous tumor size with a combination of growth and regression terms, as well as a fraction of tumor responsive to therapy. This revised model structure provided a framework to efficiently evaluate the impact of covariates and pembrolizumab exposure. Both models indicated that exposure to the drug was not a significant predictor of tumor size response, demonstrating that the dose range evaluated (2 and 10 mg/kg every 3 weeks) is likely near or at the plateau of maximal response.


Assuntos
Anticorpos Monoclonais Humanizados/farmacocinética , Antineoplásicos/farmacocinética , Melanoma/tratamento farmacológico , Modelos Biológicos , Neoplasias Cutâneas/tratamento farmacológico , Carga Tumoral/efeitos dos fármacos , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais Humanizados/administração & dosagem , Antineoplásicos/administração & dosagem , Ensaios Clínicos Fase I como Assunto/estatística & dados numéricos , Relação Dose-Resposta a Droga , Humanos , Internacionalidade , Melanoma/metabolismo , Melanoma/patologia , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Resultado do Tratamento , Carga Tumoral/fisiologia
4.
Leukemia ; 31(4): 922-933, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27686868

RESUMO

Direct therapeutic targeting of oncogenic RAS is currently still impossible due to lack of suitable pharmacological inhibitors. Because specific blockade of druggable RAS effectors might represent an alternative treatment approach, we evaluated the role of the Raf complex for multiple myeloma (MM) pathobiology. We found frequent overexpression of the Raf isoforms (A-, B- and C-Raf) and downstream activation of MEK1,2/ERK1,2 in MM cells. Concomitant inhibition of all Raf isoforms (pan-Raf inhibition) by RNAi or pharmacological inhibitors was required to strongly induce apoptosis in human MM cell lines (HMCLs), in primary MM cells in vitro, and in a syngeneic MM mouse model in vivo. The anti-MM effect of pan-Raf inhibition did not correlate with the RAS mutation status, and functionally appeared to involve both MEK-dependent and -independent mechanisms. Furthermore, transcriptome analyses revealed that pan-Raf activity affects PI3K-dependent signalling, thus highlighting a functional link between the RAS/Raf and PI3K/mTOR/Akt pro-survival pathways. Accordingly, pharmacological inhibition of PI3K strongly enhanced the anti-MM effect of pan-Raf inhibition in MM cell lines and in primary MM cells in vitro and in vivo. Concomitant pan-Raf/PI3K inhibition was also effective in carfilzomib- and lenalidomide-resistant MM models underscoring that this attractive therapeutic anti-MM strategy is suitable for immediate clinical translation.


Assuntos
Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Mutação , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Transdução de Sinais , Proteínas ras/genética , Apoptose/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Resistencia a Medicamentos Antineoplásicos , Ativação Enzimática , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Isoenzimas , Lenalidomida , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Serina-Treonina Quinases TOR/metabolismo , Talidomida/análogos & derivados , Talidomida/farmacologia
5.
Ann Oncol ; 27(7): 1291-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27117531

RESUMO

BACKGROUND: In the phase I KEYNOTE-001 study, pembrolizumab demonstrated durable antitumor activity in patients with advanced non-small-cell lung cancer (NSCLC). We sought to characterize the relationship between pembrolizumab dose, exposure, and response to define an effective dose for these patients. PATIENTS AND METHODS: Patients received pembrolizumab 2 mg/kg every 3 weeks (Q3W) (n = 55), 10 mg/kg Q3W (n = 238), or 10 mg/kg Q2W (n = 156). Response (RECIST v1.1) was assessed every 9 weeks. The relationship between the estimated pembrolizumab area under the concentration-time curve at steady state over 6 weeks (AUCss-6weeks) and the longitudinal change in tumor size (sum of longest diameters) was analyzed by regression and non-linear mixed effects modeling. This model was simultaneously fit to all tumor size data, then used to simulate response rates, normalizing the trial data across dose for prognostic covariates (tumor PD-L1 expression and EGFR mutation status). The exposure-safety relationship was assessed by logistic regression of pembrolizumab AUCss-6weeks versus occurrence of adverse events (AEs) of interest based on their immune etiology. RESULTS: Overall response rates were 15% [95% confidence interval (CI) 7%-28%] at 2 mg/kg Q3W, 25% (18%-33%) at 10 mg/kg Q3W, and 21% (95% CI 14%-30%) at 10 mg/kg Q2W. Regression analyses of percentage change from baseline in tumor size versus AUCss-6weeks indicated a flat relationship (regression slope P > 0.05). Simulations showed the exposure-response relationship to be similarly flat, thus indicating that the lowest evaluated dose of 2 mg/kg Q3W to likely be at or near the efficacy plateau. Exposure-safety analysis showed the AE incidence to be similar among the clinically tested doses. CONCLUSIONS: No significant exposure dependency on efficacy or safety was identified for pembrolizumab across doses of 2-10 mg/kg. These results support the use of a 2 mg/kg Q3W dosage in patients with previously treated, advanced NSCLC. CLINICALTRIALSGOV REGISTRY: NCT01295827.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Prognóstico , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Antígeno B7-H1/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Receptores ErbB/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Resultado do Tratamento
6.
Cell Death Dis ; 6: e1989, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26583329

RESUMO

Platelets store and release CXCL12 (SDF-1), which governs differentiation of hematopoietic progenitors into either endothelial or macrophage-foam cells. CXCL12 ligates CXCR4 and CXCR7 and regulates monocyte/macrophage functions. This study deciphers the relative contribution of CXCR4-CXCR7 in mediating the effects of platelet-derived CXCL12 on monocyte function, survival, and differentiation. CXCL12 and macrophage migration inhibitory factor (MIF) that ligate CXCR4-CXCR7 induced a dynamic bidirectional trafficking of the receptors, causing CXCR4 internalization and CXCR7 externalization during chemotaxis, thereby influencing relative receptor availability, unlike MCP-1. In vivo we found enhanced accumulation of platelets and platelet-macrophage co-aggregates in peritoneal fluid following induction of peritonitis in mice. The relative surface expression of CXCL12, CXCR4, and CXCR7 among infiltrated monocytes was also enhanced as compared with peripheral blood. Platelet-derived CXCL12 from collagen-adherent platelets and recombinant CXCL12 induced monocyte chemotaxis specifically through CXCR4 engagement. Adhesion of monocytes to immobilized CXCL12 and CXCL12-enriched activated platelet surface under static and dynamic arterial flow conditions were mediated primarily through CXCR7 and were counter-regulated by neutralizing platelet-derived CXCL12. Monocytes and culture-derived-M1-M2 macrophages phagocytosed platelets, with the phagocytic potential of culture-derived-M1 macrophages higher than M2 involving CXCR4-CXCR7 participation. CXCR7 was the primary receptor in promoting monocyte survival as exerted by platelet-derived CXCL12 against BH3-mimetic induced apoptosis (phosphatidylserine exposure, caspase-3 activation, loss of mitochondrial transmembrane potential). In co-culture experiments with platelets, monocytes predominantly differentiated into CD163(+) macrophages, which was attenuated upon CXCL12 neutralization and CXCR4/CXCR7 blocking antibodies. Moreover, OxLDL uptake by platelets induced platelet apoptosis, like other platelet agonists TRAP and collagen-related peptide (CRP). CXCL12 facilitated phagocytosis of apoptotic platelets by monocytes and M1-M2 macrophages, also promoted their differentiation into foam cells via CXCR4 and CXCR7. Thus, platelet-derived CXCL12 could regulate monocyte-macrophage functions through differential engagement of CXCR4 and CXCR7, indicating an important role in inflammation at site of platelet accumulation.


Assuntos
Plaquetas/imunologia , Células Espumosas/imunologia , Macrófagos/imunologia , Receptores CXCR/imunologia , Animais , Plaquetas/citologia , Plaquetas/metabolismo , Gatos , Diferenciação Celular/fisiologia , Sobrevivência Celular/fisiologia , Células Espumosas/citologia , Células Espumosas/metabolismo , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Monócitos/citologia , Monócitos/imunologia , Monócitos/metabolismo , Receptores CXCR/sangue
7.
Blood Cancer J ; 3: e102, 2013 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-23396385

RESUMO

Multiple myeloma (MM) is a largely incurable plasma cell malignancy with a poorly understood and heterogeneous clinical course. To identify potential, functionally relevant somatic mutations in MM, we performed whole-exome sequencing of five primary MM, corresponding germline DNA and six MM cell lines, and developed a bioinformatics strategy that also integrated published mutational data of 38 MM patients. Our analysis confirms that identical, recurrent mutations of single genes are infrequent in MM, but highlights that mutations cluster in important cellular pathways. Specifically, we show enrichment of mutations in adhesion molecules of MM cells, emphasizing the important role for the interaction of the MM cells with their microenvironment. We describe an increased rate of mutations in receptor tyrosine kinases (RTKs) and associated signaling effectors, for example, in EGFR, ERBB3, KRAS and MAP2K2, pointing to a role of aberrant RTK signaling in the development or progression of MM. The diversity of mutations affecting different nodes of a particular signaling network appears to be an intrinsic feature of individual MM samples, and the elucidation of intra- as well as interindividual redundancy in mutations that affect survival pathways will help to better tailor targeted therapeutic strategies to the specific needs of the MM patient.

8.
Indian J Clin Biochem ; 28(2): 197-200, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24426210

RESUMO

Immunoglobulin (Ig) E has been shown to be a major contributing factor for the development of bronchial hyperresponsiveness in asthma. An elevation in serum IgE levels contributes to asthma and is considered a potent predictor of the development of asthma. The objectives of the present study were to estimate the levels of total serum IgE in asthmatic and healthy control subjects and to investigate the relationship of various demographic and clinical characteristics with the total serum IgE level in asthmatics. We measured the levels of total serum IgE using the ELISA kits (AccuBind, Monobind Inc., USA). The relevant demographic and clinical data were obtained using the questionnaire. The results showed that asthmatic children had significantly elevated level of total serum IgE compared to that of the healthy controls. The levels of total IgE and IL-4 in sera of 44 asthmatic children showed a significant positive correlation. Total serum IgE >150 IU/mL was found to be significantly associated with the age, exposure to cigarette smoke, and raised eosinophil count in asthmatic children. In conclusion, the elevated level of total serum IgE may demonstrate the allergic etiology of asthma in the subjects studied.

9.
Indian J Occup Environ Med ; 16(2): 66-71, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-23580836

RESUMO

BACKGROUND: Informal/unorganised sector covers 92% of the total work force in India. About 50% of the construction industrial workers belonged to informal/unorganised sector. MATERIAL AND METHODS: The present study was undertaken to know the socio-economic status of construction worker and availing of the social security measures by this working group. RESULTS AND CONCLUSION: The study covered 150 subjects with an average age of 32 years and mean duration of work was nine years. They were poorly paid with an average income of Rs. 4956/-per month. Though the literacy rate was high (79%) yet most of them were addicted to different habits like drinking alcohol, smoking bidi, tobacco chewing etc., Abusing the family members were noted in (30%) of the cases. Their regular intake of food, usually inadequate in quantity and was mainly consisted of rice, pulses, vegetables. Though most of the subjects (73%) were living in kacha houses yet the latrine facilities were available to 62% of total covered houses. Majority of them were unaware of the different social security schemes/measures. The details have been discussed here.

10.
Oncogene ; 30(28): 3198-206, 2011 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-21478911

RESUMO

Multiple myeloma (MM) is a paradigm for a malignant disease that exploits external stimuli of the microenvironment for growth and survival. A thorough understanding of the complex interactions between malignant plasma cells and their surrounding requires a detailed analysis of the transcriptional response of myeloma cells to environmental signals. We determined the changes in gene expression induced by interleukin (IL)-6, tumor necrosis factor-α, IL-21 or co-culture with bone marrow stromal cells in myeloma cell lines. Among a limited set of genes that were consistently activated in response to growth factors, a prominent transcriptional target of cytokine-induced signaling in myeloma cells was the gene encoding the serine/threonine kinase serum/glucocorticoid-regulated kinase 1 (SGK1), which is a down-stream effector of PI3-kinase. We could demonstrate a rapid, strong and sustained induction of SGK1 in the cell lines INA-6, ANBL-6, IH-1, OH-2 and MM.1S as well as in primary myeloma cells. Pharmacologic inhibition of the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway abolished STAT3 phosphorylation and SGK1 induction. In addition, small hairpin RNA (shRNA)-mediated knock-down of STAT3 reduced basal and induced SGK1 levels. Furthermore, downregulation of SGK1 by shRNAs resulted in decreased proliferation of myeloma cell lines and reduced cell numbers. On the molecular level, this was reflected by the induction of cell cycle inhibitory genes, for example, CDKNA1/p21, whereas positively acting factors such as CDK6 and RBL2/p130 were downregulated. Our results indicate that SGK1 is a highly cytokine-responsive gene in myeloma cells promoting their malignant growth.


Assuntos
Citocinas/farmacologia , Proteínas Imediatamente Precoces/genética , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Proteínas Serina-Treonina Quinases/genética , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Citocinas/metabolismo , Regulação para Baixo/genética , Humanos , Proteínas Imediatamente Precoces/deficiência , Janus Quinases/metabolismo , Mieloma Múltiplo/metabolismo , Proteínas Serina-Treonina Quinases/deficiência , Interferência de RNA , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
11.
Br J Cancer ; 102(11): 1578-91, 2010 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-20502461

RESUMO

BACKGROUND: Heat-shock protein 90 (Hsp90) has a crucial role in both the stabilisation and regulation of various proteins, including those related to radioresistance. Inhibition of Hsp90 may therefore provide a strategy for enhancing the radiosensitivity of tumour cells. This study explores the responses of four tumour cell lines (A549, GaMG, HT 1080 and SNB19) to combined treatment with ionising radiation (IR) and two novel inhibitors of Hsp90, NVP-AUY922 and NVP-BEP800. The techniques used included cell and colony counts, expression of Hsp90, Hsp70, Akt, survivin, cleaved caspase 3, p53, cell-cycle progression and associated proteins. DNA damage was analysed by histone gammaH2AX and Comet assays. RESULTS: We found that NVP-AUY922 and NVP-BEP800 enhanced radiosensitivity in all tested cell lines. In contrast, only two cell lines (HT 1080 and GaMG) exhibited an increased rate of apoptosis after drug pretreatment, as revealed by western blot. In all tested cell lines, the expression of histone gammaH2AX, a marker of DNA double-strand breaks, after combined drug-IR treatment was higher and its decay rate was slower than those after each single treatment modality. Drug-IR treatment also resulted in impaired cell-cycle progression, as indicated by S-phase depletion and G2/M arrest. In addition, the cell cycle-associated proteins, Cdk1 and Cdk4, were downregulated after Hsp90 inhibition. INTERPRETATION: These findings show that the novel inhibitors of Hsp90 can radiosensitise tumour cell lines of different entities through destabilisation and depletion of several Hsp90 client proteins, thus causing the depletion of S phase and G2/M arrest, increased DNA damage and repair protraction and, to some extent, apoptosis. The results might have important implications for the radiotherapy of solid tumours.


Assuntos
Ciclo Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Isoxazóis/farmacologia , Neoplasias/radioterapia , Pirimidinas/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Resorcinóis/farmacologia , Benzoquinonas/farmacologia , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular , Dano ao DNA/genética , Reparo do DNA/genética , Reparo do DNA/efeitos da radiação , DNA de Neoplasias/efeitos dos fármacos , DNA de Neoplasias/metabolismo , DNA de Neoplasias/efeitos da radiação , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/efeitos da radiação , Avaliação Pré-Clínica de Medicamentos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Humanos , Lactamas Macrocíclicas/farmacologia , Neoplasias/genética , Radiossensibilizantes/farmacologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/efeitos da radiação
12.
Arch Insect Biochem Physiol ; 74(1): 52-66, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20422718

RESUMO

Our knowledge of how genes act on the nervous system in response to the environment to generate behavioral plasticity is limited. A number of recent advancements in this area concern food-related behaviors and a specific gene family called foraging (for), which encodes a cGMP-dependent protein kinase (PKG). The desert locust (Schistocerca gregaria) is notorious for its destructive feeding and long-term migratory behavior. Locust phase polyphenism is an extreme example of environmentally induced behavioral plasticity. In response to changes in population density, locusts dramatically alter their behavior, from solitary and relatively sedentary behavior to active aggregation and swarming. Very little is known about the molecular and genetic basis of this striking behavioral phenomenon. Here we initiated studies into the locust for gene by identifying, cloning, and studying expression of the gene in the locust brain. We determined the phylogenetic relationships between the locust PKG and other known PKG proteins in insects. FOR expression was found to be confined to neurons of the anterior midline of the brain, the pars intercerebralis. Our results suggest that differences in PKG enzyme activity are correlated to well-established phase-related behavioral differences. These results lay the groundwork for functional studies of the locust for gene and its possible relations to locust phase polyphenism.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/genética , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Comportamento Alimentar/fisiologia , Gafanhotos/enzimologia , Gafanhotos/genética , Sequência de Aminoácidos , Animais , Encéfalo/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/química , Feminino , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Gafanhotos/classificação , Masculino , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência
13.
Arch Environ Contam Toxicol ; 59(1): 49-61, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20082069

RESUMO

The distribution and potential sources of 16 polycyclic aromatic hydrocarbons (PAHs) in sediment cores (<63 microm particle size) of the Sundarban mangrove wetland, northeastern coast of Bay of Bengal (India), were investigated by gas chromatography coupled to mass spectrometry. The total concentrations of 16 PAHs ( summation operator(16)PAHs) ranged from 132 to 2938 ng/g, with a mean of 634 ng/g, and the sum of 10 out of 16 priority PAHs ( summation operator(10)PAH) varied from 123 to 2441 ng/g, with a mean of 555 ng/g, and the 5 carcinogenic PAHs (benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, and dibenz[a,h]anthracene) accounted for 68-73% of the priority PAHs. Maximum concentrations of the sediment core were obtained at subsoil depth of 12-16 cm. The prevalence of four to six aromatic ring PAHs and cross-plots of specific isomer ratios such as phenanthrene/anthracene, fluoranthene/pyrene, and methylphenanthrenes/phenanthrene suggested the predominance of wood and coal combustion sources, the atmospheric deposition, and surface runoff to be the major transport pathways. A good correlation existed between the benzo[a]pyrene level and the total PAH concentrations, making this compound a potential molecular marker for PAH pollution. Total TEQ (S) (carc) values calculated for samples varied from 6.95 ng/g TEQ (S) (carc) to 119 ng/g TEQ (S) (carc) , with an average of 59 ng/g dry weight TEQ (S) (carc) . The baseline data can be used for regular monitoring, considering the industrial and agricultural growth around this coastal environment.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Áreas Alagadas , Avicennia , Índia , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Medição de Risco , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
14.
Parasitology ; 136(2): 159-73, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19079847

RESUMO

SUMMARY: Distribution of 9-O-acetylated sialic acids (9-O-AcSA) on Leishmania donovani has been previously reported. Considering their role in recognition, the differential distribution of sialic acids especially 9-O-acetylated sialic acids in avirulent (UR6) versus virulent (AG83 and GE1) promastigotes of Leishmania donovani and its role in entry into macrophages was explored. Fluorimetric-HPLC, fluorimetric determination and ELISA revealed 14-, 8- and 5-fold lower sialic acids in UR6 as compared to AG83. Interestingly, on UR6, flow cytometry indicated lower (alpha2-->6)-linked sialoglycoproteins along with minimal 9-O-acetylated sialoglycoproteins by Scatchard analysis. Further, UR6 demonstrated a 9- and 14.5-fold lower infectivity and phagocytic index than AG83. Additionally, de-O-acetylation and de-sialylation of AG83 demonstrated a 3- and 1.5-fold reduced phagocytic index. The role of 9-O-AcSA in entry was further confirmed by pre-blocking the macrophage surface with a cocktail of sugars followed by microscopic quantification. The phagocytic index of AG83 exclusively through 9-O-AcSA was significantly high. Interestingly, AG83 produced higher metacyclic promastigotes containing increased 9-O-AcSA as compared to avirulent UR6 supporting its virulent nature. Taken together; our results conclusively demonstrate the increased presence of 9-O-acetylated sialic acid on promastigotes of virulent Leishmania donovani as compared to avirulent UR6 and their subsequent role in entry within macrophages.


Assuntos
Leishmania donovani/metabolismo , Leishmania donovani/patogenicidade , Macrófagos/parasitologia , Ácidos Siálicos/metabolismo , Fatores de Virulência/metabolismo , Testes de Aglutinação , Animais , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Esterases/metabolismo , Citometria de Fluxo , Fluorometria , Lectinas/isolamento & purificação , Lectinas/metabolismo , Leishmania donovani/citologia , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Confocal , Neuraminidase/metabolismo , Neuraminidase/farmacologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
15.
Hum Exp Toxicol ; 27(5): 381-6, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18715884

RESUMO

Over six million people in nine districts of West Bengal, India are exposed to very high levels of arsenic primarily through their drinking water. More than 300,000 people showed arsenic-induced skin lesions in these districts. This is regarded as the greatest arsenic calamity in the world. Chronic arsenicosis causes varied dermatological signs ranging from pigmentation changes, hyperkeratosis to non-melanocytic cancer of skin, and also malignancies in different internal organs. Higher incidences of opportunistic infections are found in the arsenic-exposed individuals, indicating that their immune systems may be impaired somehow. We have thus investigated the effect of arsenic on T-cell proliferation and cytokine secretion in 20 individuals with arsenic-induced skin lesions and compared the results with 18 arsenic-unexposed individuals. A marked dose-dependent suppression of Concanavalin A (Con A) induced T-cell proliferation was observed in the arsenic-exposed individuals compared with the unexposed (P < 0.001) individuals. This correlated with a significant decrease in the levels of secreted cytokines by the T cells (TNF-alpha, IFN-gamma, IL2, IL10, IL5, and IL4) in the exposed individuals (P < 0.001). Thus it can be inferred that arsenic exposure can cause immunosuppression in humans.


Assuntos
Intoxicação por Arsênico/imunologia , Citocinas/metabolismo , Exposição Ambiental , Linfócitos T/imunologia , Poluentes Químicos da Água/toxicidade , Adulto , Células Cultivadas , Concanavalina A/farmacologia , Estudos Transversais , Relação Dose-Resposta a Droga , Feminino , Humanos , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Dermatopatias/sangue , Dermatopatias/induzido quimicamente , Dermatopatias/patologia , Abastecimento de Água/análise
16.
Niger J Clin Pract ; 11(1): 52-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18689140

RESUMO

OBJECTIVE: To determine the misuse of antibiotics in the Pediatric outpatients department' (OPD) of a busy teaching hospital and to ascertain the probable reasons behind it. METHODS: Over a 6 months period, new cases primarily treated with antibiotics by Medical Officers (first contact physicians in Peadiatric Medicine and Surgery OPD) were recruited in the study after obtaining written consent from the parents. Various errors of antibiotic usage were noted. All Medical Officers were asked to fill up a preformed questionnaire and the parents/guardians were interviewed on their ideas about antibiotics. Data were analyzed by the statistical software SPSS 10. RESULTS: Antibiotics were prescribed in 2427 (84.9%) new patients. Misuse of antibiotics was documented in 36.8% patients (no indication in 35.3%, improper selection in 17.9% and incorrect dosage in 7.7%). All medical officers were aware that they overuse antibiotics. The various reasons sited were demand of the parents, reluctance to counsel due to patient overload, free supply of medicines from OPD and sympathetic grounds as follow up visits were uncertain. Majority of the parents/attendants belonged to poor socioeconomic status and did not have any idea regarding antibiotics. All parents wanted quick relief without hospitalization and only 2.3% were willing to revisit the OPD for the same illness. Both medical officers and parents felt that base line investigations were unnecessary. CONCLUSION: Antibiotic misuse is quite common in this part of the world. Irrational use was mostly seen in over-prescribing and improper selection of antibiotic. Poor socio-economic status and overcrowding of patients in OPD were the main responsible factors.


Assuntos
Antibacterianos/farmacologia , Prescrições de Medicamentos/estatística & dados numéricos , Erros de Medicação/estatística & dados numéricos , Pacientes Ambulatoriais , Médicos de Família , Adolescente , Criança , Pré-Escolar , Competência Clínica , Humanos , Índia , Lactente , Recém-Nascido , Estudos Prospectivos , Inquéritos e Questionários
17.
Leukemia ; 22(8): 1604-12, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18480838

RESUMO

We as well as others have recently shown that Hsp90 is overexpressed in multiple myeloma (MM) and critically contributes to tumour cell survival. Pharmacologic blockade of Hsp90 has consistently been found to induce MM cell death. However, most data have been obtained with MM cell lines whereas knowledge about the molecular effects of pharmacologic Hsp90 blockade in primary tumour cells is limited. Furthermore, these investigations have so far focused on geldanamycin derivatives. We analysed the biochemical effects of a novel diarylisoxazole-based Hsp90 inhibitor (NVP-AUY922) on signalling pathways and cell death in a large set of primary MM tumour samples and in MM cell lines. Treated cells displayed the molecular signature and pharmacodynamic properties for abrogation of Hsp90 function, such as downregulation of multiple survival pathways and strong upregulation of Hsp70. NVP-AUY922 treatment efficiently induced MM cell apoptosis and revealed both sensitive and resistant subgroups. Sensitivity was not correlated with TP53 mutation or Hsp70 induction levels and stromal cells from the bone marrow microenvironment were unable to abrogate NVP-AUY922-induced apoptosis of MM cells. Thus, NVP-AUY922 may be a promising drug for treatment of MM and clinical studies are warranted.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Isoxazóis/farmacologia , Mieloma Múltiplo/tratamento farmacológico , Resorcinóis/farmacologia , Transdução de Sinais , Apoptose , Linhagem Celular Tumoral , Técnicas de Cocultura , Humanos , Isoxazóis/uso terapêutico , Mieloma Múltiplo/patologia , Resorcinóis/uso terapêutico
18.
Verh Dtsch Ges Pathol ; 91: 330-7, 2007.
Artigo em Alemão | MEDLINE | ID: mdl-18314631

RESUMO

HSP90's are overexpressed in different cancer types and they probably are required to sustain aberrant signalling in malignant cells. Recently, pharmacological inhibition of HSP90 was found to suppress growth of myeloma cell lines and in primary myeloma cells. Therefore, we wanted to investigate the role of HSP90alpha and HSP90beta in the pathogenesis of malignant myeloma (MM) in more detail. Immunohistochemistry was employed to examine the expression of HSP90alpha and HSP90beta in MM. The importance of HSP90 for survival of MM -cells was investigated by SiRNA-mediated knockdown of HSP90 and blockade of the IL-6R/STAT3 and the MAPK signaling pathways in vitro. HSP90alpha and HSP90beta were overexpressed in majority of investigated MM cases, but not in MGUS or in normal plasma cells. SiRNA-mediated knockdown of HSP90 or treatment with the novel HSP90 inhibitor 17-DMAG attenuated the levels of STAT3 and phospho-ERK and decreased the viability of MM cells. The knockdown of HSP90alpha was sufficient to induce apoptosis. This effect was strongly increased when both HSP90s were targeted, indicating a cooperation of both. HSP90 critically contributes to myeloma survival in the context of its microenvironment and therefore strengthen the potential value of HSP90 as a therapeutic target.

19.
Br Dent J ; 201(6): 349-50, 2006 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-16990884

RESUMO

This paper reports a patient with a history of breast cancer, who presented with altered sensation to the right lower lip and chin. An orthopantomogram showed a probable dentigerous cyst associated with an unerupted lower wisdom tooth, which was closely related to the inferior dental canal. The tooth and cyst were enucleated under general anaesthesia. The subsequent histopathology report concluded that the cyst contained metastatic adenocarcinoma from a primary breast tumour.


Assuntos
Adenocarcinoma/secundário , Neoplasias da Mama/patologia , Cisto Dentígero/patologia , Neoplasias Mandibulares/secundário , Parestesia/etiologia , Adulto , Feminino , Humanos , Lábio
20.
Cell Biol Toxicol ; 21(1): 41-52, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15868487

RESUMO

The trace mineral vanadium inhibits cancer development in a variety of experimental animal models. The present study was to gain insight into a putative anticancer effect of vanadium in a rat model of colon carcinogenesis. The in vivo study was intended to clarify the effect of vanadium on DNA-protein cross-links (DPC), surface level changes of aberrant crypt foci (ACF) and biotransformation status during 1,2-dimethylhydrazine (1,2-DMH) induced preneoplastic rat colon carcinogenesis. The comet assay showed statistically higher mean base values of DNA-protein mass (p<0.01) and mean frequencies of tailed cells (p<0.001) in the carcinogen-induced group after treatment with proteinase K. Treatment with vanadium in the form of ammonium monovanadate supplemented ad libitum in drinking water for the entire experimental period caused a significant (p<0.02) reduction (40%) in DNA-protein cross-links in colon cells. Further, the biotransformation status of vanadium was ascertained measuring the drug metabolising enzymes, glutathione S-transferase (GST) and cytochrome P-450 (Cyt P-450). Significantly, there was an increase in glutathione S-transferase and cytochrome P-450 levels (p<0.01 and p<0.02, respectively) in rats supplemented with vanadium as compared to their carcinogen controls. As an endpoint marker, we also evaluated the effect of vanadium on surface level changes of aberrant crypt foci induced by 1,2-DMH by scanning electron microscopy. Animals induced with 1,2-DMH and supplemented with vanadium showed a marked improvement in colonic architecture with less number of aberrant crypt foci in contrast to the animals induced with 1,2-DMH alone, thereby exhibiting its anti-carcinogenicity by modulating the markers studied herein.


Assuntos
Neoplasias do Colo/prevenção & controle , Dano ao DNA/efeitos dos fármacos , Vanádio/farmacologia , 1,2-Dimetilidrazina , Animais , Peso Corporal/efeitos dos fármacos , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/patologia , Ensaio Cometa , Sistema Enzimático do Citocromo P-450/metabolismo , DNA/química , DNA/genética , DNA/metabolismo , Glutationa Transferase/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Mucosa Intestinal/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Proteínas/química , Proteínas/metabolismo , Ratos , Ratos Sprague-Dawley
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