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1.
Neurosci Inform ; 2(3): 100035, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36819833

RESUMO

COVID-19 epidemic has swiftly disrupted our day-to-day lives affecting the international trade and movements. Wearing a face mask to protect one's face has become the new normal. In the near future, many public service providers will expect the clients to wear masks appropriately to partake of their services. Therefore, face mask detection has become a critical duty to aid worldwide civilization. This paper provides a simple way to achieve this objective utilising some fundamental Machine Learning tools as TensorFlow, Keras, OpenCV and Scikit-Learn. The suggested technique successfully recognises the face in the image or video and then determines whether or not it has a mask on it. As a surveillance job performer, it can also recognise a face together with a mask in motion as well as in a video. The technique attains excellent accuracy. We investigate optimal parameter values for the Convolutional Neural Network model (CNN) in order to identify the existence of masks accurately without generating over-fitting.

2.
Molecules ; 24(18)2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31546767

RESUMO

Corilagin (ß-1-O-galloyl-3,6-(R)-hexahydroxydiphenoyl-d-glucose), an ellagitannin, is one of the major bioactive compounds present in various plants. Ellagitannins belong to the hydrolyzable tannins, a group of polyphenols. Corilagin shows broad-spectrum biological, and therapeutic activities, such as antioxidant, anti-inflammatory, hepatoprotective, and antitumor actions. Natural compounds possessing antitumor activities have attracted significant attention for treatment of cancer. Corilagin has shown inhibitory activity against the growth of numerous cancer cells by prompting cell cycle arrest at the G2/M phase and augmented apoptosis. Corilagin-induced apoptosis and autophagic cell death depends on production of intracellular reactive oxygen species in breast cancer cell line. It blocks the activation of both the canonical Smad and non-canonical extracellular-signal-regulated kinase/Akt (protein kinase B) pathways. The potential apoptotic action of corilagin is mediated by altered expression of procaspase-3, procaspase-8, procaspase-9, poly (ADP ribose) polymerase, and Bcl-2 Bax. In nude mice, corilagin suppressed cholangiocarcinoma growth and downregulated the expression of Notch1 and mammalian target of rapamycin. The aim of this review is to summarize the anticancer efficacy of corilagin with an emphasis on the molecular mechanisms involving various signaling pathways in tumor cells.


Assuntos
Antineoplásicos/uso terapêutico , Glucosídeos/uso terapêutico , Taninos Hidrolisáveis/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Disponibilidade Biológica , Glucosídeos/efeitos adversos , Glucosídeos/química , Humanos , Taninos Hidrolisáveis/efeitos adversos , Taninos Hidrolisáveis/química , Modelos Biológicos , Neoplasias/metabolismo , Transdução de Sinais/efeitos dos fármacos
3.
Biochem Biophys Res Commun ; 495(2): 1915-1921, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29208466

RESUMO

Human triple-negative breast cancer (TNBC) is poorly diagnosed and unresponsive to conventional hormone therapy. Chetomin (CHET), a fungal metabolite synthesized by Chaetomium cochliodes, has been reported as a promising anticancer and antiangiogenic agent but the complete molecular mechanism of its anticancer potential remains to be elucidated. In our study, we explored the anti-neoplastic action of CHET on TNBC cells. Cytotoxicity studies were performed in human TNBC cells viz. MDA-MB-231 and MDA-MB-468 cells by Sulforhodamine B assay. It exhibited antiproliferative response and induced apoptosis in both the cell types. Cell cycle analysis revealed that it increases the sub G0/G1 phase cell population. Modulation of mitochondrial membrane potential, activation of caspase 3/7 and a remarkable increase in the expression of cleaved PARP and increased chromatin condensation was observed after CHET treatment in MDA-MB-231 and MDA-MB-468 cells. Additionally, an elevated level of intracellular Ca2+ played an important role in CHET mediated cell death response. Calcium overload in mitochondria led to release of cytochrome c which in turn triggered caspase-3 mediated cell death. Inhibition of calcium signalling using BAPTA-AM reduced apoptosis confirming the involvement of calcium signalling in CHET induced cell death. Chetomin also inhibited PI3K/mTOR cell survival pathway in human TNBC cells. The overall findings suggest that Chetomin inhibited the growth of human TNBC cells by caspase-dependent apoptosis and modulation of PI3K/mTOR signalling and could be used as a novel chemotherapeutic agent for the treatment of human TNBC in future.


Assuntos
Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Dissulfetos/administração & dosagem , Alcaloides Indólicos/administração & dosagem , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/patologia
4.
Arch Insect Biochem Physiol ; 89(1): 18-34, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25580830

RESUMO

A trypsin inhibitor purified from the seeds of the Manila tamarind, Pithecellobium dulce (PDTI), was studied for its effects on growth parameters and developmental stages of Helicoverpa armigera. PDTI exhibited inhibitory activity against bovine trypsin (∼86%; ∼1.33 ug/ml IC50). The inhibitory activity of PDTI was unaltered over a wide range of temperature, pH, and in the presence of dithiothreitol. Larval midgut proteases were unable to digest PDTI for up to 12 h of incubation. Dixon and Lineweaver-Burk double reciprocal plots analysis revealed a competitive inhibition mechanism and a Ki of ∼3.9 × 10(-8) M. Lethal dose (0.50% w/w) and dosage for weight reduction by 50% (0.25% w/w) were determined. PDTI showed a dose-dependent effect on mean larval weight and a series of nutritional disturbances. In artificial diet at 0.25% w/w PDTI, the efficiency of conversion of ingested food, of digested food, relative growth rate, and growth index declined, whereas approximate digestibility, relative consumption rate, metabolic cost, consumption index, and total developmental period were increased in larvae. This is the first report of antifeedant and antimetabolic activities of PDTI on midgut proteases of H. armigera.


Assuntos
Fabaceae/química , Inseticidas/isolamento & purificação , Mariposas , Peptídeos/isolamento & purificação , Proteínas de Plantas/isolamento & purificação , Animais , Eletroforese em Gel de Poliacrilamida , Feminino , Inseticidas/química , Larva , Masculino , Peptídeos/química , Proteínas de Plantas/química , Pupa , Sementes/química
5.
Pestic Biochem Physiol ; 116: 94-102, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25454525

RESUMO

A trypsin inhibitor purified from the seeds of Tamarindus indica by Sephadex G-75, DEAE-Sepharose and Trypsin-Sepharose CL-4B columns was studied for its antifeedant, larvicidal, pupicidal and growth inhibitory activities against Helicoverpa armigera larvae. Tamarindus trypsin inhibitor (TTI) exhibited inhibitory activity towards total gut proteolytic enzymes of H. armigera (~87%) and bovine trypsin (~84%). Lethal doses which caused mortality and weight reduction by 50% were 1% w/w and 0.50% w/w, respectively. IC50 of TTI against Helicoverpa midgut proteases and bovine trypsin were ~2.10 µg/ml and 1.68 µg/ml respectively. In larval feeding studies the 21 kDa Kunitz-type protein was found to retard growth and development, prolonged the larval-pupal development durations along with adversely affecting the fertility and fecundity of H. armigera. In artificial diet at 0.5% w/w TTI, the efficiency of conversion of ingested food as well as of digested food, relative growth rate, growth index declined whereas approximate digestibility, metabolic cost, relative consumption rate, consumption index and total developmental period enhanced for H. armigera larvae. These results suggest that TTI has toxic and adverse effect on the developmental physiology of H. armigera and could be useful in controlling the pest H. armigera.


Assuntos
Inseticidas/toxicidade , Mariposas/efeitos dos fármacos , Tamarindus , Inibidores da Tripsina/toxicidade , Animais , Feminino , Fertilidade/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/enzimologia , Larva/efeitos dos fármacos , Masculino , Mariposas/crescimento & desenvolvimento , Mariposas/fisiologia , Peptídeo Hidrolases/metabolismo , Sementes
6.
Biomed Res Int ; 2014: 202398, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25298962

RESUMO

An affinity purified trypsin inhibitor from the seed flour extracts of Madhuca indica (MiTI) on denaturing polyacrylamide gel electrophoresis showed that MiTI consisted of a single polypeptide chain with molecular mass of ~19.8 kDa. MiTI inhibited the total proteolytic and trypsin-like activities of the midgut proteinases of Helicoverpa armigera larvae by 87.51% and 76.12%, respectively, at concentration of 5 µg/mL with an IC50 of 1.75 µg/mL against trypsin like midgut proteinases. The enzyme kinetic studies demonstrated that MiTI is a competitive inhibitor with a K i value of 4.1 × 10(-10) M for Helicoverpa trypsin like midgut proteinases. In vivo experiments with different concentrations of MiTI in artificial diet (0.5, 1.0, and 1.5% w/w) showed an effective downfall in the larval body weight and an increase in larval mortality. The concentration of MiTI in the artificial diet to cause 50% mortality (LD50) of larvae was 1.5% w/w and that to cause reduction in mass of larvae by 50% (ED50) was 1.0% w/w. Nutritional indices observations suggest the toxic and adverse effects of MiTI on the growth and development of H. armigera larvae. The results suggest a strong bioinsecticidal potential of affinity purified MiTI which can be exploited in insect pest management of crop plants.


Assuntos
Madhuca/química , Mariposas/crescimento & desenvolvimento , Mariposas/fisiologia , Inibidores de Proteases/farmacologia , Sementes/química , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Antimetabólitos/farmacologia , Bioensaio , Peso Corporal/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Cinética , Larva/efeitos dos fármacos , Peso Molecular , Mariposas/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Temperatura , Inibidores da Tripsina/farmacologia
7.
Biochem Res Int ; 2014: 361821, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24860667

RESUMO

Helicoverpa armigera is one of the major devastating pests of crop plants. In this context a serine peptidase inhibitor purified from the seeds of Butea monosperma was evaluated for its effect on developmental physiology of H. armigera larvae. B. monosperma peptidase inhibitor on 12% denaturing polyacrylamide gel electrophoresis exhibited a single protein band of ~14 kDa with or without reduction. In vitro studies towards total gut proteolytic enzymes of H. armigera and bovine trypsin indicated measurable inhibitory activity. B. monosperma peptidase inhibitor dose for 50% mortality and weight reduction by 50% were 0.5% w/w and 0.10% w/w, respectively. The IC50 of B. monosperma peptidase inhibitor against total H. armigera gut proteinases activity was 2.0 µg/mL. The larval feeding assays suggested B. monosperma peptidase inhibitor to be toxic as reflected by its retarded growth and development, consequently affecting fertility and fecundity of pest and prolonging the larval-pupal duration of the insect life cycle of H. armigera. Supplementing B. monosperma peptidase inhibitor in artificial diet at 0.1% w/w, both the efficiencies of conversion of ingested as well as digested food were downregulated, whereas approximate digestibility and metabolic cost were enhanced. The efficacy of Butea monosperma peptidase inhibitor against progressive growth and development of H. armigera suggest its usefulness in insect pest management of food crops.

8.
Arch Insect Biochem Physiol ; 85(2): 94-113, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24436204

RESUMO

A trypsin inhibitor was purified from the seeds of Eugenia jambolana (Jambul) with a fold purification of 14.28 and a yield recovery of 2.8%. Electrophoretic analysis of E. jambolana trypsin inhibitor (EjTI) revealed a molecular weight of approximately 17.4 kDa on 12% denaturing polyacrylamide gel electrophoresis with or without reduction. EjTI exhibited high stability over a wide range of temperatures (4-80 °C for 30 min) and pH (3.0-10.0) and inhibited trypsin-like activities of the midgut proteinases of fourth instar Helicoverpa armigera larvae by approximately 86%. Feeding assays containing 0.05, 0.15, and 0.45 (% w/w) EjTI on functionally important fourth-instar larvae indicated a dose-dependent downfall in the larval body weight as well as on extent of survival. The nutritional analysis suggests that EjTI exerts toxic effects on H. armigera. Dixon plot analysis revealed competitive inhibition of larval midgut proteinases by EjTI, with an inhibition constant (Ki ) of approximately 3.1 × 10(-9) M. However, inhibitor kinetics using double reciprocal plots for trypsin inhibition demonstrated a mixed inhibition pattern. These observations suggest the potential of E. jambolana trypsin inhibitor protein in insect pest management.


Assuntos
Mariposas , Sementes/química , Syzygium/química , Inibidores da Tripsina/farmacologia , Animais , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida , Cinética , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , Temperatura , Inibidores da Tripsina/isolamento & purificação
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