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1.
PLoS Biol ; 20(6): e3001677, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35696430

RESUMO

The valence and salience of individual odorants are modulated by an animal's innate preferences, learned associations, and internal state, as well as by the context of odorant presentation. The mechanisms underlying context-dependent flexibility in odor valence are not fully understood. Here, we show that the behavioral response of Caenorhabditis elegans to bacterially produced medium-chain alcohols switches from attraction to avoidance when presented in the background of a subset of additional attractive chemicals. This context-dependent reversal of odorant preference is driven by cell-autonomous inversion of the response to these alcohols in the single AWC olfactory neuron pair. We find that while medium-chain alcohols inhibit the AWC olfactory neurons to drive attraction, these alcohols instead activate AWC to promote avoidance when presented in the background of a second AWC-sensed odorant. We show that these opposing responses are driven via engagement of distinct odorant-directed signal transduction pathways within AWC. Our results indicate that context-dependent recruitment of alternative intracellular signaling pathways within a single sensory neuron type conveys opposite hedonic valences, thereby providing a robust mechanism for odorant encoding and discrimination at the periphery.


Assuntos
Neurônios Receptores Olfatórios , Receptores Odorantes , Álcoois , Animais , Caenorhabditis elegans/fisiologia , Odorantes , Neurônios Receptores Olfatórios/fisiologia , Células Receptoras Sensoriais , Olfato/fisiologia
2.
Toxicol Mech Methods ; 34(6): 676-693, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38481097

RESUMO

Introduction/Background: Curcuma longa, a plant native to the Indian subcontinent has a variety of biological activities. Curcumin is the most abundant and biologically active compound with many therapeutic properties. Demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC) - the two other bioactive components present in Curcuma longa, besides curcumin, are collectively termed curcuminoids. Apart from the well-known curcumin, BDMC also has been reported to possess promising biological and pharmacological effects, but very little scientific evidence on its safety assessment has been published.Objective: The present study was undertaken to determine the safety of pure BDMC from Curcuma longa extract in rodents which comprises of general toxicity (both four weeks and three months duration), reproductive/developmental toxicity and genotoxicity studies.Methods: The Good Laboratory Practice studies were carried out in accordance with the test guidelines established by the Organization for Economic Cooperation and Development.Results: No treatment-related adverse findings were seen in general toxicity testing and a no observed adverse effect level (NOAEL) of 1000 mg/kg/day was established after four weeks (sub-acute) and three-months (sub-chronic) dosing. Evaluation of fertility, embryo-fetal, and post-natal reproductive and developmental parameters also showed no adverse findings with a NOAEL of 1000 mg/kg/day established. The results of genotoxicity as evaluated by in vitro reverse mutation assay, and in vivo micronucleus test in mice indicate that BDMC did not induce any genotoxic effects.Conclusion: Oral administration of BDMC is safe in rodents and non-mutagenic, with no adverse effects under experimental conditions.


Assuntos
Curcuma , Diarileptanoides , Rizoma , Animais , Curcuma/química , Masculino , Diarileptanoides/toxicidade , Feminino , Rizoma/química , Extratos Vegetais/toxicidade , Testes para Micronúcleos , Nível de Efeito Adverso não Observado , Curcumina/análogos & derivados , Curcumina/toxicidade , Testes de Mutagenicidade , Ratos Sprague-Dawley , Camundongos , Relação Dose-Resposta a Droga , Ratos , Reprodução/efeitos dos fármacos
3.
Conscious Cogn ; 115: 103581, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37847944

RESUMO

In an item-method directed forgetting task, memory instructions presumably operate by promoting further rehearsal of to-be-remembered (TBR) items and limiting encoding of to-be-forgotten (TBF) items. We asked whether diverting attentional resources away from TBF items and towards a new item that needed to be committed to memory would improve forgetting. To this end, study words in our experiments were presented singly followed by a remember instruction (single-TBR), by a forget instruction (single-TBF), or else were replaced by a new word to be remembered (replace-TBR) in place of the original study word which could be forgotten (replace-TBF). A typical directed forgetting effect was observed across single and replace trials. However, there was no compelling evidence that forgetting was better for replace-TBF compared to single-TBF words, suggesting that, by itself, the explicit redirection of attentional and other processing resources away from forget items may not be sufficient to improve item-method directed forgetting.


Assuntos
Eletroencefalografia , Potenciais Evocados , Humanos , Sinais (Psicologia) , Tempo de Reação , Rememoração Mental
4.
Artigo em Inglês | MEDLINE | ID: mdl-37325971

RESUMO

The COVID-19 pandemic has affected the world, leading to significant morbidity and mortality. Various meteorological parameters are considered essential for the viability and transmission of the virus. Multiple reports from various parts of the world suggest a correlation between the disease spread and air pollution severity. This study was carried out to identify the relationship between meteorological parameters, air pollution, and COVID-19 in New Delhi, one of the worst-affected states in India. We studied air pollution and meteorological parameters in New Delhi, India. We obtained data about COVID-19 occurrence, meteorological parameters, and air pollution indicators from various sources from Apr 1, 2020, till Nov 12, 2020. We performed correlational analysis and employed autoregressive distributed lag models (ARDLM) for identifying the relationship between COVID-19 cases with air pollution and meteorological parameters. We found a significant impact of PM 2.5, PM 10, and meteorological parameters on COVID-19. There was a significant positive correlation between daily COVID-19 cases and COVID-19-related deaths with PM2.5 and PM10 levels. Increasing temperature and windspeed were associated with a reduction in the number of cases while increasing humidity was associated with increased cases. This study demonstrated a significant association of PM2.5 and PM10 with daily COVID-19 cases and COVID-19-related mortality. This knowledge will likely help us prepare well for the future and implement air pollution control measures for other airborne disease epidemics.

5.
BMC Public Health ; 20(1): 771, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32448153

RESUMO

BACKGROUND: Indian women are more prone to first birth at a relatively younger age after marriage. Also, we do not have sufficient literature available that focuses on contraceptive use before first birth. The analysis of the present study was done using data from the fourth round of National Family Health Survey (2015-16), India. The objectives of the present study were to measure the levels and trends of contraceptive use before first birth among Indian ever married women, aged 15-34 years. METHODS: The study includes 279,896 ever married women aged 15-34 years at the time of the NFHS-4 survey. To identify the socio-demographic determinants governing the pioneering study behavior, multivariable techniques have been used in the analysis. The statistical significance of the relationship between socio-demographic factors and contraceptive use prior to first birth was tested using a chi-squared test for association. Hosmer Lemeshow statistics and Nagelkerke R square have been used to check how well the logistic regression model fits the data. Map of India showing different zonal classification is made using the ArcGIS software version 10.3. RESULT: The trends of contraceptive usage show a decline in use before first birth and the various socio-demographic factors affecting the use of contraceptive before first birth are religion, caste, education, wealth index, media exposure, age at marriage and the zonal classifications. CONCLUSION: The noticeable result in this study is the comparative decline in contraceptive use by women in India before first birth in NFHS-4 with respect to previous NFHS done in India. The likelihood of using contraception before first birth is significantly affected by factors like place of residence, religion, caste, current age of women, age at marriage, education level of women, wealth index, media exposure and zonal classification.


Assuntos
Fatores Etários , Ordem de Nascimento/psicologia , Comportamento Contraceptivo/tendências , Anticoncepção/tendências , Casamento/psicologia , Adolescente , Adulto , Anticoncepção/psicologia , Comportamento Contraceptivo/psicologia , Estudos Transversais , Países em Desenvolvimento , Feminino , Humanos , Índia , Modelos Logísticos , Casamento/estatística & dados numéricos , Gravidez , Religião , Classe Social , Fatores Socioeconômicos , Adulto Jovem
6.
Cytokine ; 102: 211-221, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29108796

RESUMO

Alzheimer's disease (AD) is a chronic disorder that slowly worsens and impairs the person's memory, learning, reasoning, judgment, communication and familiar tasks with loss of orientation. AD is characterized clinically by cognitive deficit and pathologically by the deposition of ß amyloid plaques, neurofibrillary tangles, associated with degeneration of the cholinergic forebrain. Withanone (WS-2), a compound isolated from root extract of Withania somnifera at doses administered orally/day to wistar rats for duration of 21 days showed significant improvement in the cognitive skill by inhibiting amyloid ß-42 and attenuated the elevated levels of pro-inflammatory cytokines like TNF alpha, IL-1 beta, IL-6, MCP-1, Nitric oxide, lipid peroxidation and both ß- and γ- secretase enzymatic activity. Administration of WS-2 also significantly reversed the decline in acetyl choline and Glutathione (GSH) activity. None of the treatments that are available today alter the underlying causes of this terminal disease. Few preliminary clinical treatments have demonstrated that some plant medicines do ameliorate and improve memory and learning in patients with mild-to-moderate AD. WS-2 showed promise in AD treatment because of cognitive benefits and more importantly, mechanisms of action with respect to the fundamental pathophysiology of the disease, not limited to the inhibition of AChE, but also include the modification of Aß processing, protection against oxidative stress and anti-inflammatory effects.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Fitoterapia , Triterpenos/uso terapêutico , Withania , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/psicologia , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Withania/química , Vitanolídeos
7.
Nature ; 492(7429): 387-92, 2012 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-23222541

RESUMO

Protease-activated receptor 1 (PAR1) is the prototypical member of a family of G-protein-coupled receptors that mediate cellular responses to thrombin and related proteases. Thrombin irreversibly activates PAR1 by cleaving the amino-terminal exodomain of the receptor, which exposes a tethered peptide ligand that binds the heptahelical bundle of the receptor to affect G-protein activation. Here we report the 2.2 Å resolution crystal structure of human PAR1 bound to vorapaxar, a PAR1 antagonist. The structure reveals an unusual mode of drug binding that explains how a small molecule binds virtually irreversibly to inhibit receptor activation by the tethered ligand of PAR1. In contrast to deep, solvent-exposed binding pockets observed in other peptide-activated G-protein-coupled receptors, the vorapaxar-binding pocket is superficial but has little surface exposed to the aqueous solvent. Protease-activated receptors are important targets for drug development. The structure reported here will aid the development of improved PAR1 antagonists and the discovery of antagonists to other members of this receptor family.


Assuntos
Receptor PAR-1/química , Motivos de Aminoácidos , Sítios de Ligação , Cristalização , Cristalografia por Raios X , Ativação Enzimática/genética , Humanos , Hidrólise , Lactonas/química , Lactonas/farmacologia , Ligantes , Modelos Moleculares , Simulação de Dinâmica Molecular , Infarto do Miocárdio/prevenção & controle , Conformação Proteica , Piridinas/química , Piridinas/farmacologia , Receptor PAR-1/agonistas , Receptor PAR-1/antagonistas & inibidores , Receptor PAR-1/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/classificação , Receptores de Trombina
8.
Cytokine ; 79: 103-13, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26799426

RESUMO

OBJECTIVE & DESIGN: Investigation was carried out on Saponin 1 (SAP-1), a novel molecule isolated from Parthenium hysterophorus, on proinflammatory (Th1) & anti-inflammatory (Th2) cytokines in blood of arthritic balb/c mice. METHODS: Adjuvant induced developing inflammatory arthritis was induced in mice which were treated with SAP-1 in graded oral doses. The molecular markers were determined using Flow Cytometry which uses sensitivity of amplified fluorescence detection to measure soluble analytes in particle based immune assay. The T-helper (Th1) deviated cells produce detectable level of Tumor necrosis factor (TNF-alpha), interleukin-2 (IL-2) & interferon-gamma (IFN-gamma), while the Th2 deviated cells produce significant amount of interleukin-4 (IL-4) and interleukin-5 (IL-5). RESULTS: SAP-1 at graded oral doses inhibited expression of IFN-gamma & TNF-alpha in serum & correspondingly increased expression of IL-4 significantly. SAP-1 also inhibited IL-17 and CD4(+)CD25(+) cell population showing to have suppressive effect on Th-17 pathway as well as T-regulatory cells. It also suppressed the increased levels of pro-inflammatory mediators like IL-1ß and NO. Inhibitors of Cox-2 and MCP-1 provide effective improvements in signs and symptoms of Rheumatoid Arthritis. SAP-1 decreased the elevated concentration of both COX-2 and MCP-1 in arthritic animals. CONCLUSIONS: SAP-1 diminishes Th1 immunity activation, a primary cause of arthritis, in favour of Th2 dominance, which reduces arthritic condition in mice displaying immune-modulatory potential.


Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Saponinas/uso terapêutico , Equilíbrio Th1-Th2/efeitos dos fármacos , Animais , Artrite Experimental/patologia , Artrite Reumatoide/patologia , Quimiocina CCL2/antagonistas & inibidores , Quimiocina CCL2/metabolismo , Ciclo-Oxigenase 2/metabolismo , Feminino , Interferon gama/biossíntese , Interleucina-17/biossíntese , Interleucina-1beta/metabolismo , Interleucina-2/biossíntese , Interleucina-4/biossíntese , Interleucina-5/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis , Óxido Nítrico/metabolismo , Partenogênese , Células Th1/imunologia , Células Th2/imunologia , Fator de Necrose Tumoral alfa/biossíntese
9.
BMC Public Health ; 15: 1316, 2015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-26714857

RESUMO

BACKGROUND: There exist ample of research literature investigating the various facet of contraceptive use behaviors in India but the use of contraception by married Indian women, prior to having their first pregnancy has been neglected so far. This study attempts to identify the socio demographic determinants and differentials of contraceptive use or non use by a woman in India, before she proceeds to have her first child. The analysis was done using data from the third National Family Health Survey (2005-2006), India. METHODS: This study utilized information from 54,918 women who ever have been married and whose current age at the time of NFHS-3 survey was 15-34 years. To identify the crucial socio-demographic determinants governing this pioneering behavior, logistic regression technique has been used. Hosmer Lemeshow test and ROC curve analysis was also performed in order to check the fitting of logistic regression model to the data under consideration. RESULTS: Of all the considered explanatory variables religion, caste, education, current age, age at marriage, media exposure and zonal classifications were found to be significantly affecting the study behavior. Place of residence i.e. urban--rural locality came to be insignificant in multivariable logistic regression. CONCLUSIONS: In the light of sufficient evidences confirming the presence of early marriages and child bearing practices in India, conjunct efforts are required to address the socio demographic differentials in contraceptive use by the young married women prior to their first pregnancy. Encouraging women to opt for higher education, ensuring marriages only after legal minimum age at marriage and promoting the family planning programs via print and electronic media may address the existing socio economic barriers. Also, the family planning programs should be oriented to take care of the geographical variations in the study behavior.


Assuntos
Comportamento Contraceptivo/estatística & dados numéricos , Anticoncepção/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Feminino , Humanos , Índia , Modelos Logísticos , Casamento/estatística & dados numéricos , Meios de Comunicação de Massa , Curva ROC , Análise de Regressão , Características de Residência , Fatores Socioeconômicos , Adulto Jovem
10.
J Biol Chem ; 288(7): 5127-35, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23264619

RESUMO

CLEC-2 is a member of new family of C-type lectin receptors characterized by a cytosolic YXXL downstream of three acidic amino acids in a sequence known as a hemITAM (hemi-immunoreceptor tyrosine-based activation motif). Dimerization of two phosphorylated CLEC-2 molecules leads to recruitment of the tyrosine kinase Syk via its tandem SH2 domains and initiation of a downstream signaling cascade. Using Syk-deficient and Zap-70-deficient cell lines we show that hemITAM signaling is restricted to Syk and that the upstream triacidic amino acid sequence is required for signaling. Using surface plasmon resonance and phosphorylation studies, we demonstrate that the triacidic amino acids are required for phosphorylation of the YXXL. These results further emphasize the distinct nature of the proximal events in signaling by hemITAM relative to ITAM receptors.


Assuntos
Plaquetas/metabolismo , Tirosina/química , Sequência de Aminoácidos , Aminoácidos/química , Citosol/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Cinética , Lectinas Tipo C/química , Lectinas Tipo C/metabolismo , Glicoproteínas de Membrana/metabolismo , Modelos Biológicos , Dados de Sequência Molecular , Fosforilação , Proteínas Tirosina Quinases/metabolismo , Homologia de Sequência de Aminoácidos , Transdução de Sinais , Ressonância de Plasmônio de Superfície , Quinase Syk , Venenos de Víboras/química , Proteína-Tirosina Quinase ZAP-70/química
11.
J Pharmacol Exp Ther ; 351(3): 538-48, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25253883

RESUMO

The heterogeneity and severity of certain autoimmune diseases and B-cell malignancies warrant simultaneous targeting of multiple disease-relevant signaling pathways. Dual inhibition of spleen tyrosine kinase (SYK) and Janus kinase (JAK) represents such a strategy and may elicit several benefits relative to selective kinase inhibition, such as gaining control over a broader array of disease etiologies, reducing probability of selection for bypass disease mechanisms, and the potential that an overall lower level suppression of individual targets may be sufficient to modulate disease activity. To this end, we provide data on the discovery and preclinical development of PRT062070 [4-(cyclopropylamino)-2-({4-[4-(ethylsulfonyl)piperazin-1-yl]phenyl}amino)pyrimidine-5-carboxamide hydrochloride], an orally active kinase inhibitor that demonstrates activity against SYK and JAK. Cellular assays demonstrated specific inhibitory activity against signaling pathways that use SYK and JAK1/3. Limited inhibition of JAK2 was observed, and PRT062070 did not inhibit phorbol 12-myristate 13-acetate-mediated signaling or activation in B and T cells nor T-cell antigen receptor-mediated signaling in T cells, providing evidence for selectivity of action. Potent antitumor activity was observed in a subset of B-cell lymphoma cell lines. After oral dosing, PRT062070 suppressed inflammation and autoantibody generation in a rat collagen-induced arthritis model and blocked B-cell activation and splenomegaly in a mouse model of chronic B-cell antigen receptor stimulation. PRT062070 is currently under evaluation in a phase I dose escalation study in patients with B-cell leukemia and lymphoma (NCT01994382), with proof-of-concept studies in humans planned to assess therapeutic potential in autoimmune and malignant diseases.


Assuntos
Artrite Experimental/tratamento farmacológico , Autoimunidade/efeitos dos fármacos , Modelos Animais de Doenças , Linfoma de Células B/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Sulfonas/uso terapêutico , Animais , Artrite Experimental/imunologia , Artrite Experimental/patologia , Autoimunidade/fisiologia , Bovinos , Relação Dose-Resposta a Droga , Feminino , Humanos , Linfoma de Células B/imunologia , Linfoma de Células B/patologia , Camundongos , Camundongos Endogâmicos BALB C , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Distribuição Aleatória , Ratos , Ratos Endogâmicos Lew , Sulfonas/química , Sulfonas/farmacologia , Resultado do Tratamento
13.
Cureus ; 16(1): e52754, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38389646

RESUMO

The development of nanocosmetics nanotechnology has ushered in a new age in cosmetic research, completely changing the skincare scene. This abstract investigates the relationship between skincare and nanotechnology, particularly emphasizing the effects of nanocosmetics on skin health. Cosmetics, known as "nanocosmetics," use materials at the nanoscale, typically between 1 and 100 nanometers, to improve the effectiveness and delivery of active chemicals. Nanotechnology in cosmetics allows for the development of sophisticated delivery methods that provide enhanced stability and tailored distribution, including nanoemulsions and nanocapsules. This breakthrough overcomes the constraints of conventional formulations by enabling the entry of active ingredients into the skin's deeper layers. Studies investigating nanocosmetics and skin health were included. This encompassed in vitro studies, animal models, and clinical studies of various designs. Exclusion criteria included studies focusing solely on nanotechnology unrelated to skin health or nanocosmetics and review articles editorials, commentaries, and conference abstracts. Nanocosmetics is a groundbreaking development in skincare that provides creative answers to a range of skin issues. As the area develops, realizing the full potential of nanotechnology in fostering ideal skin health will need sustained research and adherence to safety regulations.

14.
Carcinogenesis ; 34(7): 1558-66, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23430955

RESUMO

Plant extracts, a concoction of bioactive non-nutrient phytochemicals, have long served as the most significant source of new leads for anticancer drug development. Explored for their unique medicinal properties, the leaves of Piper betel, an evergreen perennial vine, are a reservoir of phenolics with antimutagenic, antitumor and antioxidant activities. Here, we show that oral feeding of betel leaf extract (BLE) significantly inhibited the growth of human prostate xenografts implanted in nude mice compared with vehicle-fed controls. To gain insights into the 'active principles', we performed a bioactivity-guided fractionation of methanolic BLE employing solvents of different polarity strengths using classical column chromatography. This approach yielded 15 fractions, which were then pooled to 10 using similar retention factors on thin-layer chromatographs. Bioactivity assays demonstrated that one fraction in particular, F2, displayed a 3-fold better in vitro efficacy to inhibit proliferation of prostate cancer cells than the parent BLE. The presence of phenols, hydroxychavicol (HC) and chavibetol (CHV), was confirmed in F2 by nuclear magnetic resonance, high-performance liquid chromatography and mass spectroscopy. Further, the HC containing F2 subfraction was found to be ~8-fold more potent than the F2 subfraction that contained CHV, in human prostate cancer PC-3 cells as evaluated by the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide assay. Removing CHV from F2 remarkably decreased the IC50 of this fraction, indicating that HC is perhaps the major bioactive constituent, which is present to an extent of 26.59% in BLE. These data provide evidence that HC is a potential candidate for prostate cancer management and warrants further preclinical evaluation.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Piper/química , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Neoplasias da Próstata/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/química , Apoptose , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Eugenol/análogos & derivados , Eugenol/química , Eugenol/isolamento & purificação , Eugenol/uso terapêutico , Humanos , Imuno-Histoquímica , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Masculino , Metanol/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fitoterapia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Solventes/química , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Pharmacol Exp Ther ; 344(2): 378-87, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23220742

RESUMO

B-cell receptor (BCR) associated kinases including spleen tyrosine kinase (SYK) contribute to the pathogenesis of B-cell malignancies. SYK is persistently phosphorylated in a subset of non-Hodgkin lymphoma (NHL) and chronic lymphocytic leukemia (CLL), and SYK inhibition results in abrogation of downstream kinase activity and apoptosis. P505-15 (also known as PRT062607) is a novel, highly selective, and orally bioavailable small molecule SYK inhibitor (SYK IC(50) = 1 nM) with anti-SYK activity that is at least 80-fold greater than its affinity for other kinases. We evaluated the preclinical characteristics of P505-15 in models of NHL and CLL. P505-15 successfully inhibited SYK-mediated B-cell receptor signaling and decreased cell viability in NHL and CLL. Oral dosing in mice prevented BCR-mediated splenomegaly and significantly inhibited NHL tumor growth in a xenograft model. In addition, combination treatment of primary CLL cells with P505-15 plus fludarabine produced synergistic enhancement of activity at nanomolar concentrations. Our findings support the ongoing development of P505-15 as a therapeutic agent for B-cell malignancies. A dose finding study in healthy volunteers has been completed.


Assuntos
Antineoplásicos/farmacologia , Linfócitos B/efeitos dos fármacos , Cicloexilaminas/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/farmacologia , Vidarabina/análogos & derivados , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linfócitos B/enzimologia , Linfócitos B/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cicloexilaminas/administração & dosagem , Cicloexilaminas/farmacocinética , Cicloexilaminas/uso terapêutico , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Citometria de Fluxo , Humanos , Leucemia Linfocítica Crônica de Células B/enzimologia , Leucemia Linfocítica Crônica de Células B/patologia , Linfoma não Hodgkin/enzimologia , Linfoma não Hodgkin/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Fosforilação , Pirimidinas/administração & dosagem , Pirimidinas/farmacocinética , Pirimidinas/uso terapêutico , Baço/efeitos dos fármacos , Baço/enzimologia , Quinase Syk , Vidarabina/administração & dosagem , Vidarabina/farmacocinética , Vidarabina/farmacologia , Vidarabina/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Blood ; 118(24): 6342-52, 2011 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-22025527

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma, and the role of SYK in its pathogenesis is not completely understood. Using tissue microarray, we demonstrated for the first time that SYK protein is activated in 27 of 61 (44%) primary human DLBCL tissues. Among DLBCL cell lines, 7 were sensitive and 3 were resistant to a highly specific SYK inhibitor, PRT060318. In sensitive DLBCL cells, SYK inhibition blocked the G(1)-S transition and caused cell-cycle arrest. This effect was reproduced by genetic reduction of SYK using siRNA. A detailed analysis of the BCR signaling pathways revealed that the consequence of SYK inhibition on PLCγ2 and AKT, as opposed to ERK1/2, was responsible for cell-cycle arrest. Genetic knock-down of these key molecules decelerated the proliferation of lymphoma cells. In addition, BCR signaling can be blocked by PRT060318 in primary lymphoma cells. Together, these findings provide insights into cellular pathways required for lymphoma cell growth and support the rationale for considering SYK inhibition as a potentially useful therapy for DLBCL. The results further suggest the possibility of using PLCγ2 and AKT as biomarkers to predict therapeutic response in prospective clinical trials of specific SYK inhibitors.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Proteínas de Neoplasias/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Fase G1/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Linfonodos/efeitos dos fármacos , Linfonodos/metabolismo , Linfonodos/patologia , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Terapia de Alvo Molecular , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fosfolipase C gama/antagonistas & inibidores , Fosfolipase C gama/genética , Fosfolipase C gama/metabolismo , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Quinase Syk , Células Tumorais Cultivadas
17.
Blood ; 117(7): 2241-6, 2011 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-21088136

RESUMO

Heparin-induced thrombocytopenia (HIT) is a major cause of morbidity and mortality resulting from the associated thrombosis. Extensive studies using our transgenic mouse model of HIT have shown that antibodies reactive with heparin-platelet factor 4 complexes lead to FcγRIIA-mediated platelet activation in vitro as well as thrombocytopenia and thrombosis in vivo. We tested PRT-060318 (PRT318), a novel selective inhibitor of the tyrosine kinase Syk, as an approach to HIT treatment. PRT318 completely inhibited HIT immune complex-induced aggregation of both human and transgenic HIT mouse platelets. Transgenic HIT model mice were treated with KKO, a mouse monoclonal HIT-like antibody, and heparin. The experimental group received orally dosed PRT318, whereas the control group received vehicle. Nadir platelet counts of PRT318-treated mice were significantly higher than those of control mice. When examined with a novel thrombosis visualization technique, mice treated with PRT318 had significantly reduced thrombosis. The Syk inhibitor PRT318 thus prevented both HIT immune complex-induced thrombocytopenia and thrombosis in vivo, demonstrating its activity in HIT.


Assuntos
Heparina/efeitos adversos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Trombocitopenia/prevenção & controle , Trombose/prevenção & controle , Animais , Complexo Antígeno-Anticorpo/sangue , Complexo Antígeno-Anticorpo/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Plaquetas/enzimologia , Plaquetas/imunologia , Humanos , Técnicas In Vitro , Peptídeos e Proteínas de Sinalização Intracelular/sangue , Camundongos , Camundongos Transgênicos , Ativação Plaquetária/efeitos dos fármacos , Ativação Plaquetária/imunologia , Proteínas Tirosina Quinases/sangue , Receptores de IgG/antagonistas & inibidores , Quinase Syk , Trombocitopenia/induzido quimicamente , Trombocitopenia/imunologia , Trombose/induzido quimicamente , Trombose/imunologia
18.
Blood ; 118(18): 5000-10, 2011 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-21881044

RESUMO

Although current antiplatelet therapies provide potent antithrombotic effects, their efficacy is limited by a heightened risk of bleeding and failure to affect vascular remodeling after injury. New lines of research suggest that thrombosis and hemorrhage may be uncoupled at the interface of pathways controlling thrombosis and inflammation. Here, as one remarkable example, studies using a novel and highly selective pharmacologic inhibitor of the spleen tyrosine kinase Syk [PRT060318; 2-((1R,2S)-2-aminocyclohexylamino)-4-(m-tolylamino)pyrimidine-5-carboxamide] coupled with genetic experiments, demonstrate that Syk inhibition ameliorates both the acute and chronic responses to vascular injury without affecting hemostasis. Specifically, lack of Syk (murine radiation chimeras) attenuated shear-induced thrombus formation ex vivo, and PRT060318 strongly inhibited arterial thrombosis in vivo in multiple animal species while having minimal impact on bleeding. Furthermore, leukocyte-platelet-dependent responses to vascular injury, including inflammatory cell recruitment and neointima formation, were markedly inhibited by PRT060318. Thus, Syk controls acute and long-term responses to arterial vascular injury. The therapeutic potential of Syk may be exemplary of a new class of antiatherothrombotic agents that target the interface between thrombosis and inflammation.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Proteínas Tirosina Quinases/fisiologia , Lesões do Sistema Vascular/fisiopatologia , Cicatrização/genética , Animais , Cicloexilaminas/farmacologia , Cicloexilaminas/uso terapêutico , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos , Camundongos Knockout , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/genética , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Suínos , Quinase Syk , Trombose/tratamento farmacológico , Trombose/genética , Trombose/patologia , Lesões do Sistema Vascular/genética , Lesões do Sistema Vascular/reabilitação
19.
Proc Natl Acad Sci U S A ; 107(43): 18605-10, 2010 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-20930120

RESUMO

Toward understanding their redundancies and interactions in hemostasis and thrombosis, we examined the roles of thrombin receptors (protease-activated receptors, PARs) and the ADP receptor P2RY12 (purinergic receptor P2Y G protein-coupled 12) in human and mouse platelets ex vivo and in mouse models. Par3(-/-) and Par4(+/-) mouse platelets showed partially decreased responses to thrombin, resembling those in PAR1 antagonist-treated human platelets. P2ry12(+/-) mouse platelets showed partially decreased responses to ADP, resembling those in clopidogrel-treated human platelets. Par3(-/-) mice showed nearly complete protection against carotid artery thrombosis caused by low FeCl(3) injury. Par4(+/-) and P2ry12(+/-) mice showed partial protection. Increasing FeCl(3) injury abolished such protection; combining partial attenuation of thrombin and ADP signaling, as in Par3(-/-):P2ry12(+/-) mice, restored it. Par4(-/-) mice, which lack platelet thrombin responses, showed still better protection. Our data suggest that (i) the level of thrombin driving platelet activation and carotid thrombosis was low at low levels of arterial injury and increased along with the contribution of thrombin-independent pathways of platelet activation with increasing levels of injury; (ii) although P2ry12 acts downstream of PARs to amplify platelet responses to thrombin ex vivo, P2ry12 functioned in thrombin/PAR-independent pathways in our in vivo models; and (iii) P2ry12 signaling was more important than PAR signaling in hemostasis models; the converse was noted for arterial thrombosis models. These results make predictions being tested by ongoing human trials and suggest hypotheses for new antithrombotic strategies.


Assuntos
Hemostasia/fisiologia , Receptores Ativados por Proteinase/sangue , Receptores Purinérgicos P2Y12/sangue , Trombose/sangue , Proteínas Adaptadoras de Transdução de Sinal , Difosfato de Adenosina/sangue , Difosfato de Adenosina/farmacologia , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Moléculas de Adesão Celular/sangue , Moléculas de Adesão Celular/deficiência , Moléculas de Adesão Celular/genética , Proteínas de Ciclo Celular , Feminino , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Knockout , Modelos Biológicos , Receptores Ativados por Proteinase/deficiência , Receptores Ativados por Proteinase/genética , Receptores Purinérgicos P2Y12/deficiência , Receptores Purinérgicos P2Y12/genética , Receptores de Trombina/sangue , Receptores de Trombina/deficiência , Receptores de Trombina/genética , Transdução de Sinais , Trombina/metabolismo , Trombina/farmacologia , Trombose/etiologia
20.
Bioinformation ; 19(4): 460-463, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37822827

RESUMO

It is of interest to document histo-pathological patterns in hysterectomy specimens at tertiary care centre in India. This study included 442 cases. In this study, leiomyoma (9.17 %) was the most common preoperatively clinical diagnosis made in hysterectomy specimen. In this study, uterine fibroid showed a 90.47% correlation between pre-operative and histological findings. There was a 50 % correlation noted between adenomyosis and endocervical polyp.

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