Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Pharm Biol ; 55(1): 1489-1499, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28367666

RESUMO

CONTEXT: Abnormal angiogenesis and evasion of apoptosis are hallmarks of cancer. Accordingly, anti-angiogenic and pro-apoptotic therapies are effective strategies for cancer treatment. Medicinal plants, namely, Eugenia jambolana Lam. (Myrtaceae), Musa paradisiaca L. (Musaceae), and Coccinia indica Wight & Arn. (Cucurbitaceae), have not been greatly investigated for their anticancer potential. OBJECTIVE: We investigated the anti-angiogenic and pro-apoptotic efficacy of ethyl acetate (EA) and n-butanol (NB) extracts of E. jambolana (seeds), EA extracts of M. paradisiaca (roots) and C. indica (leaves) with respect to mammary neoplasia. MATERIALS AND METHODS: Effect of extracts (2-200 µg/mL) on cytotoxicity and MCF-7, MDA-MB-231 and endothelial cell (EC) proliferation and in vitro angiogenesis were evaluated by MTT, 3[H]thymidine uptake and EC tube formation assays, respectively. In vivo tumour proliferation, VEGF secretion and angiogenesis were assessed using the Ehrlich ascites tumour (EAT) model followed by rat corneal micro-pocket and chicken chorioallantoic membrane (CAM) assays. Apoptosis induction was assessed by morphological and cell cycle analysis. RESULTS: EA extracts of E. jambolana and M. paradisiaca exhibited the highest cytotoxicity (IC50 25 and 60 µg/mL), inhibited cell proliferation (up to 81%), and tube formation (83% and 76%). In vivo treatment reduced body weight (50%); cell number (16.5- and 14.7-fold), secreted VEGF (∼90%), neoangiogenesis in rat cornea (2.5- and 1.5-fold) and CAM (3- and 1.6-fold) besides EAT cells accumulation in sub-G1 phase (20% and 18.38%), respectively. DISCUSSION AND CONCLUSION: Considering the potent anti-angiogenic and pro-apoptotic properties, lead molecules from EA extracts of E. jambolana and M. paradisiaca can be developed into anticancer drugs.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Carcinoma de Ehrlich/prevenção & controle , Membrana Corioalantoide/irrigação sanguínea , Cucurbitaceae/química , Musa/química , Neovascularização Patológica , Neovascularização Fisiológica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Syzygium/química , Fator A de Crescimento do Endotélio Vascular/farmacologia , 1-Butanol/química , Acetatos/química , Inibidores da Angiogênese/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Carcinoma de Ehrlich/sangue , Carcinoma de Ehrlich/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Embrião de Galinha , Neovascularização da Córnea/patologia , Neovascularização da Córnea/fisiopatologia , Neovascularização da Córnea/prevenção & controle , Relação Dose-Resposta a Droga , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos , Fitoterapia , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Raízes de Plantas/química , Plantas Medicinais , Ratos Wistar , Sementes/química , Fatores de Tempo , Carga Tumoral/efeitos dos fármacos
2.
Apoptosis ; 21(5): 578-93, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26921178

RESUMO

TRAIL, an apoptosis inducing cytokine currently in phase II clinical trial, was investigated for its capability to induce apoptosis in six different human tumor cell lines out of which three cell lines showed resistance to TRAIL induced apoptosis. To investigate whether Anacardic acid (A1) an active component of Anacardium occidentale can sensitize the resistant cell lines to TRAIL induced apoptosis, we treated the resistant cells with suboptimal concentration of A1 and showed that it is a potent enhancer of TRAIL induced apoptosis which up-regulates the expression of both DR4 and DR5 receptors, which has been observed in the cellular, protein and mRNA levels. The death receptors upregulation consequent to A1 treatment was corroborated by the activation of p53 as well as phosphorylation of p38 and JNK MAP kinases and concomitant inactivation of NFκß and ERK signaling cascades. Also, A1 modulated the expression of key apoptotic players like Bax, Bcl-2 and CAD along with the abatement of tumor angiogenesis in vivo in EAT mouse model. Thus, post A1 treatment the TRAIL resistant cells turned into TRAIL sensitive cells. Hence our results demonstrate that A1 can synergize TRAIL induced apoptosis through the upregulation of death receptors and downregulation of anti-apoptotic proteins in cancer context.


Assuntos
Ácidos Anacárdicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Ácidos Anacárdicos/administração & dosagem , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Lipossomos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , RNA Mensageiro/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima
3.
Mol Carcinog ; 54(5): 333-50, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24265228

RESUMO

The expression of metastasis associated protein (MTA1) correlates well with tumor metastasis; however its role as a proangiogenic protein and the molecular mechanisms underlying the same are not fully understood. In this study the MTA1 protein was expressed and purified to evaluate its angiogenic potential. In both MCF-7 and MDA-MB-231 cells, endogenous MTA1 protein was localized in the nucleus; while added recombinant MTA1 protein was bound to cell membrane as per immunofluorescence data. MTA1 was detected both in conditioned media and in human serum samples. Recombinant MTA1 regulated cellular functions of HUVEC's such as, proliferation, tube formation, and migration. MTA1 was more potent than VEGF in inducing invasion of breast cancer cells. Analogous to VEGF, MTA1 could induce angiogenesis in both non-tumor and tumor context, as verified by rat cornea, shell less CAM and xenograft models respectively. However MTA-1 was more potent an inducer of angiogenesis. VEGF or Flt-1 gene promoter, luciferase gene reporter analysis revealed that MTA1 up regulates the expression of VEGF and its receptor Flt-1 genes. Kinetics of VEGF-induced expression of MTA1 and qPCR studies showed that there is an increased expression of MTA1 in tumor cells. VEGF induced phosphorylation of endogenous MTA1 on tyrosine residues; phosphorylation was mediated through VEGFR2 and p38-MAP kinase. Recombinant MTA1 activated signaling, in MCF-7 and MDA-MB-231 cells, involved ERK and JNK pathways. In conclusion, MTA1 is a potent angiogenic molecule and cross talk between VEGF and MTA1 protein regulates tumor angiogenesis and metastasis.


Assuntos
Neoplasias da Mama/patologia , Histona Desacetilases/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Melanoma Experimental/patologia , Proteínas Repressoras/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Apoptose , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Movimento Celular , Proliferação de Células , Células Cultivadas , Membrana Corioalantoide , Feminino , Imunofluorescência , Regulação Neoplásica da Expressão Gênica , Histona Desacetilases/genética , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Camundongos , Neovascularização Patológica , Fosforilação , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transativadores , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/genética , Cicatrização , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Med Eng Phys ; 126: 104138, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38621836

RESUMO

Lung cancer is one of the most deadly diseases in the world. Lung cancer detection can save the patient's life. Despite being the best imaging tool in the medical sector, clinicians find it challenging to interpret and detect cancer from Computed Tomography (CT) scan data. One of the most effective ways for the diagnosis of certain malignancies like lung tumours is Positron Emission Tomography (PET) imaging. So many diagnosis models have been implemented nowadays to diagnose various diseases. Early lung cancer identification is very important for predicting the severity level of lung cancer in cancer patients. To explore the effective model, an image fusion-based detection model is proposed for lung cancer detection using an improved heuristic algorithm of the deep learning model. Firstly, the PET and CT images are gathered from the internet. Further, these two collected images are fused for further process by using the Adaptive Dilated Convolution Neural Network (AD-CNN), in which the hyperparameters are tuned by the Modified Initial Velocity-based Capuchin Search Algorithm (MIV-CapSA). Subsequently, the abnormal regions are segmented by influencing the TransUnet3+. Finally, the segmented images are fed into the Hybrid Attention-based Deep Networks (HADN) model, encompassed with Mobilenet and Shufflenet. Therefore, the effectiveness of the novel detection model is analyzed using various metrics compared with traditional approaches. At last, the outcome evinces that it aids in early basic detection to treat the patients effectively.


Assuntos
Aprendizado Profundo , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Heurística , Tomografia Computadorizada por Raios X , Tomografia por Emissão de Pósitrons , Algoritmos
5.
Chemosphere ; 346: 140486, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37875216

RESUMO

Nitrogen dioxide (NO2) is one of the toxic gases produced by chemical industries, power plants, and vehicles. In this work, we demonstrate an inexpensive sensing platform for NO2 detection at room temperature (RT-32 °C) based on a charge transfer mechanism. Three-dimensional hierarchical SnS2 and SnS2/mesoporous TiO2 nanocomposites were synthesized via the solvothermal method. SnS2/20 wt% mesoporous TiO2 nanocomposites sample showed 245.4% enhanced response compared to pristine SnS2. The fabricated device exhibits excellent selectivity among all other interfering gases with one-month stability. The rapid response and enhanced response achieved were obtained for the minimum concentration of 2 ppm NO2. The formation of heterojunction between SnS2 and mesoporous TiO2 has a synergetic effect, providing more active sites and porous structures for the detection of NO2 gas molecules.


Assuntos
Indústria Química , Dióxido de Nitrogênio , Temperatura , Gases
6.
Environ Monit Assess ; 184(5): 2677-89, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21713495

RESUMO

We investigated the influence on bacterial community and biochemical variables through mechanical disturbance of sediment-akin to small-scale mining in Kalbadevi beach, Ratnagiri, a placer-rich beach ecosystem which is a potential mining site. Changes were investigated by comparing three periods, namely phase I before disturbance, phase II just after disturbance, and phase III 24 h after disturbance as the bacterial generation time is ≤7 h. Cores from dune, berm, high-, mid-, and low-tide were examined for changes in distribution of total bacterial abundance, total direct viability (counts under aerobic and anaerobic conditions), culturability and biochemical parameters up to 40 cm depth. Results showed that bacterial abundance decreased by an order from 10(6) cells g(-1) sediment, while, viability reduced marginally. Culturability on different-strength nutrient broth increased by 155% during phase II. Changes in sedimentary proteins, carbohydrates, and lipids were marked at berm and dune and masked at other levels by tidal influence. Sedimentary ATP reduced drastically. During phase III, Pearson's correlation between these variables evolved from non-significant to significant level. Thus, simulated disturbance had a mixed effect on bacterial and biochemical variables of the sediments. It had a negative impact on bacterial abundance, viability and ATP but positive impact on culturability. Viability, culturability, and ATP could act as important indicators reflecting the disturbance in the system at short time intervals. Culturability, which improved by an order, could perhaps be a fraction that contributes to restoration of the system at bacterial level. This baseline information about the potential mining site could help in developing rational approach towards sustainable harnessing of resources with minimum damage to the ecosystem.


Assuntos
Bactérias/crescimento & desenvolvimento , Praias , Sedimentos Geológicos/química , Mineração/métodos , Poluentes da Água/análise , Bactérias/classificação , Monitoramento Ambiental , Sedimentos Geológicos/microbiologia , Índia , Medição de Risco , Poluição da Água/estatística & dados numéricos
7.
Rev Sci Instrum ; 93(2): 023504, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35232154

RESUMO

India is responsible for the supply of diagnostic neutral beam systems for ITER to diagnose its helium ash during the deuterium-tritium plasma phase using the charge exchange recombination spectroscopy technique. Considering the many first of its kind in terms of technologies and beam development aspects, ITER Indian domestic agency has adopted a strategy of developing the technology and beam experimentation in parallel. On the beam development front three test beds, namely, the ROBIN (Rf Operated Beam source in India for Negative ion research), the TWIN (TWo rf driver-based Indigenously built Negative ion source), and the INTF (INdian Test Facility) are presently in their various phases of operation, optimization, and setting up at IPR, respectively. Experiments related to plasma production, beam production, and acceleration up to 30 keV in volume and surface mode have been performed on ROBIN. The maximum negative hydrogen ion current density to a tune of 27 mA/cm2 is obtained in the surface mode with Cs injection. Optimal source performance requires optimal surface conditions, minimum impurities, careful characterization of the plasma, cesium feed and its redistribution, and optimal wall temperatures of the surfaces of the plasma box and the plasma grid. A combination of probe, optical, vacuum, laser based, electrical, and calorimetric diagnostic measurements enables such a control. At ROBIN, the above diagnostics are being used regularly. The operational and diagnostic experiences on ROBIN shall provide the desired experience and database for operations of TWIN and INTF in the coming years. A large number of conventional and advanced diagnostic techniques are used for plasma and beam characterization. These diagnostics are suitable not only to detect and understand the plasma but also for studies related to impurity evolution. The temporal evolution of impurities significantly impacts the plasma and beam properties. The studies help in establishing correlations between physical parameters and operational parameters to optimize the source performance ensuring adequate safety and investment protection. This paper will present a brief overview of various diagnostics implemented, lessons learned, and the results obtained from ROBIN. In addition, an outline of the diagnostics planned for INTF based on the experience and understandings developed during the present experiments on ROBIN and TWIN and considering the requirements of large systems shall be discussed.

8.
Front Immunol ; 13: 906063, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874709

RESUMO

Angiotensin-converting enzyme 2 (ACE2) and neuropilin 1, a vascular endothelial growth factor (VEGF) receptor, were identified to bind to the SARS-CoV-2 spike receptor-binding domain (spike RBD). In silico analysis based on 3D structure, multiple sequence alignment, and molecular docking of second domain of soluble Flt-1 (sFlt-1) and spike RBD revealed structural similarities, sequence homology, and protein-protein interaction. Interaction and binding of recombinant spike RBD (rspike RBD) and recombinant sFlt-1 (rsFlt-1) in vitro induced a conformational change, as revealed by spectrofluorimetric data, with increased fluorescence intensity in emission spectra as compared to either of the proteins alone. Results on ELISA confirmed the binding and cross-reactivity of rspike-RBD and rsFlt-1 as determined by using either specific antibodies towards each protein or immunized human serum. We found that polyclonal or monoclonal anti-spike RBD antibodies can recognize either rsFlt-1 or rspike RBD, showing cross-reactivity for the two proteins in a dose-dependent binding response. Recognition of bound rspike RBD or rsFlt-1 by anti-Flt-1 or anti-spike RBD antibodies, respectively, as observed by immunoblotting, further confirmed interaction between the two proteins. Immunoprecipitation and immunoblot analysis demonstrated the identification of rspike RBD binding to the Flt-1 receptor on A549 cells. Further, the binding of rspike RBD to Flt-1 receptor was shown using immunofluorescence on 2D-culture or 3D-spheroid of MDA-MB-231 cells, which over-express Flt-1 receptor. Together, our study concludes that the Flt-1 receptor is a novel binding partner for SARS-CoV-2 spike RBD.


Assuntos
SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , COVID-19 , Humanos , Simulação de Acoplamento Molecular , Glicoproteína da Espícula de Coronavírus/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
9.
Prog Mol Subcell Biol ; 52: 49-76, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21877263

RESUMO

Manganese is an essential trace metal that is not as readily oxidizable like iron. Several bacterial groups posses the ability to oxidize Mn effectively competing with chemical oxidation. The oxides of Mn are the strongest of the oxidants, next to oxygen in the aquatic environment and therefore control the fate of several elements. Mn oxidizing bacteria have a suit of enzymes that not only help to scavenge Mn but also other associated elements, thus playing a crucial role in biogeochemical cycles. This article reviews the importance of manganese and its interaction with microorganisms in the oxidative Mn cycle in aquatic realms.


Assuntos
Bactérias , Manganês , Proteínas de Bactérias/química , Ferro , Oxirredução
10.
Extremophiles ; 15(2): 129-53, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21210167

RESUMO

Extremophiles occur in a diverse range of habitats, from the frigid waters of Antarctic to the superheated plumes of hydrothermal vents. Their in-depth study could provide important insights into the biochemical, ecological and evolutionary aspects of marine microbes. The cellular machinery of such extreme-lovers could be highly flexible to cope with such harsh environments. Extreme conditions of temperature, pressure, salinity, pH, oxidative stress, radiation, etc., above the physiological tolerance level can disrupt the natural conformation of proteins in the cell. The induction of stress proteins (heat/cold shock proteins/salt stress proteins/pressure-induced proteins) plays a vital role in the acclimatization of extremophiles. The present review focuses on the in vitro studies conducted on the transcripts and translational pattern of stress proteins in extremophiles. Though some proteins are unique, a commonality in stress resistance mechanism has been observed, for example, the universal occurrence of HSP60, 70 and the expression of metabolic and DNA repair proteins. The review highlights that among all the stressful conditions, salt/osmotic stress evokes the expression of highest number of transcripts/proteins while psychrophilic condition the least.


Assuntos
Variação Genética , Halobacteriales/genética , Proteínas de Choque Térmico/genética , RNA Mensageiro/metabolismo , Chaperonina 60/metabolismo , DNA/genética , Reparo do DNA , Proteínas de Choque Térmico HSP70/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio , Estresse Oxidativo , Pressão , Dobramento de Proteína , Especificidade da Espécie , Temperatura
11.
Curr Microbiol ; 62(3): 840-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21046399

RESUMO

Co immobilization by two manganese oxidizing isolates from Carlsberg Ridge waters (CR35 and CR48) was compared with that of Mn at same molar concentrations. At a lower concentration of 10 µM, CR35 and CR48 immobilized 22 and 23 fM Co cell(-1) respectively, which was 1.4 to 2 times higher than that of Mn oxidation, while at 10 mM the immobilization was 15-69 times lower than that of Mn. Scanning electron microscope and energy dispersive X-ray analyses of intact bacterial cells grown in 1 mM Co revealed Co peaks showing extracellular binding of the metal. However, it was evident from transmission electron microscope analyses that most of the sequestered Co was bound intracellularly along the cell membrane in both the isolates. Change in morphology was one of the strategies bacteria adopted to counter metal stress. The cells grew larger and thus maintained a lower than normal surface area-volume ratio on exposure to Co to reduce the number of binding sites. An unbalanced growth with increasing Co additions was observed in the isolates. Cells attained a length of 10-18 µm at 10 mM Co which was 11-15 times the original cell length. Extensive cell rupture indicated that Co was harmful at this concentration. It is apparent that biological and optimal requirement of Mn is more than Co. Thus, these differences in the immobilization of the two metals could be driven by the differences in the requirement, cell physiology and the affinities of the isolates for the concentrations of the metals tested.


Assuntos
Bactérias/metabolismo , Cobalto/metabolismo , Sedimentos Geológicos/microbiologia , Manganês/metabolismo , Bactérias/química , Bactérias/ultraestrutura , Oceano Índico , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Oxirredução , Análise de Sequência de DNA , Espectrometria por Raios X
12.
Environ Monit Assess ; 173(1-4): 117-25, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20300837

RESUMO

A study to examine the short-term effect of nitrate and organic carbon addition on denitrification activity was carried out on sediments from a mangrove ecosystem prone to anthropogenic activities (Divar, Goa, India). Laboratory microcosms were prepared using sediment sectioned at every 2-cm-depth interval from the surface to 10 cm. The incubations were subjected to varying nitrate amendments at concentrations ranging from 0, 5, 10, 20, 40 to 60 µmol l(-1) (up to three times more than measured in field). Nitrous oxide production rates increased significantly (n=15; p<0.001) on addition of the nutrient at all depths investigated indicating that denitrification in mangrove sediments was NO[Formula: see text] limited. Incubations amended with organic carbon were prepared using glucose as a substrate with concentrations ranging from 0%, 0.1%, 0.3%, 0.5%, 0.75% to 1%. No significant increase in N2O production was observed on organic C addition. When both the substrates were in excess (1 mmol KNO3+1 mmol glucose), potential denitrification rates decreased with depth and were up to 38 times higher than the in situ denitrification activity varying from 81.26 to 304.09 µmol N2O-N m(-2) h(-1). These results reveal that mangrove sediments could act as a sink for nitrate and microbially mediated denitrification could effectively reduce N load controlling any adverse environmental impact in the adjoining estuarine system.


Assuntos
Sedimentos Geológicos/análise , Nitratos/análise , Carbono/análise , Desnitrificação , Monitoramento Ambiental , Índia
13.
Environ Monit Assess ; 182(1-4): 385-95, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21318266

RESUMO

Coastal regions are potential zones for production of methane which could be governed by ecological/environmental differences or even sediment properties of a niche. In order to test the hypothesis that methanogenesis in most marine sediments could be driven more by proteins than by carbohydrates and lipid content of labile organic matter (LOM), incubation experiments were carried out with sediments from different environmental niches to measure methane production. The methane production rates were examined in relationship to the sediment biochemistry, i.e., carbohydrates, proteins, and lipids. The gas production measured by head space method ranged from 216 ng g( -1) day( -1) in the mangrove sediments to 3.1 µg g( -1) day( -1) in the shallow Arabian Sea. LOM ranged from 1.56 to 2.85 mg g( -1) in the shallow Arabian Sea, from 3.35 to 5.43 mg g( -1) in the mangrove estuary, and from 0.66 to 0.70 mg g( -1) in the sandy sediments with proteins contributing maximum to the LOM pool. Proteins influenced methane production in the clayey sediments of shallow depths of the Arabian Sea (r = 0.933, p < 0.001) and mangrove estuary (r = 0.981, p < 0.001) but in the sandy beach sediments, carbohydrates (r = 0.924, p < 0.001) governed the net methane production. The gas production was more pronounced in shallow and surface sediments and it decreased with depth apparently governed by the decrease in lability index. Thus, the lability index and protein content are important factors that determine methane production rates in these coastal ecosystems.


Assuntos
Poluentes Atmosféricos/análise , Sedimentos Geológicos/química , Metano/análise , Poluentes Químicos da Água/análise , Poluição do Ar/estatística & dados numéricos , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Praias/estatística & dados numéricos , Monitoramento Ambiental , Sedimentos Geológicos/microbiologia , Metano/metabolismo , Oceanos e Mares , Água do Mar/química , Água do Mar/microbiologia
14.
RSC Adv ; 11(31): 19283-19293, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35478632

RESUMO

In the past few decades, air and water pollution by organic dyes has become a serious concern due to their high toxicity. Removal of these organic dyes from polluted water bodies is a serious environmental concern and the development of new advanced photocatalytic materials for decomposing organic dyes can be a good solution. In this work, layered molybdenum disulfide/nickel disulfide (MoS2/NiS2) nanocomposites with various NiS2 content was synthesized by a one-step hydrothermal method using citric acid as a reducing agent. The X-ray diffraction pattern shows the hexagonal and cubical crystal structure of MoS2 and NiS2, respectively. Morphological analysis confirms the formation of MoS2/NiS2 nanosheets. The elemental composition of the samples was carried out by XPS, which shows a significant interaction between NiS2 and MoS2. The photocatalytic performance of MoS2/NiS2 nanocomposites was studied by the degradation of rhodamine B (RhB). Ni-4 sample shows higher photocatalytic activity with a maximum degradation of 90.61% under visible light irradiation for 32 min.

15.
Front Bioeng Biotechnol ; 9: 761266, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34950641

RESUMO

A biosurfactant producing bacterium was identified as Pseudomonas aeruginosa DNM50 based on molecular characterization (NCBI accession no. MK351591). Structural characterization using MALDI-TOF revealed the presence of 12 different congeners of rhamnolipid such as Rha-C8-C8:1, Rha-C10-C8:1, Rha-C10-C10, Rha-C10-C12:1, Rha-C16:1, Rha-C16, Rha-C17:1, Rha-Rha-C10:1-C10:1, Rha-Rha-C10-C12, Rha-Rha-C10-C8, Rha-Rha-C10-C8:1, and Rha-Rha-C8-C8. The radical scavenging activity of rhamnolipid (DNM50RL) was determined by 2, 3-diphenyl-1-picrylhydrazyl (DPPH) assay which showed an IC50 value of 101.8 µg/ ml. The cytotoxic activity was investigated against MDA-MB-231 breast cancer cell line by MTT (4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide) assay which showed a very low IC50 of 0.05 µg/ ml at 72 h of treatment. Further, its activity was confirmed by resazurin and trypan blue assay with IC50 values of 0.01 µg/ml and 0.64 µg/ ml at 72 h of treatment, respectively. Thus, the DNM50RL would play a vital role in the treatment of breast cancer targeting inhibition of p38MAPK.

16.
J Gene Med ; 12(12): 968-80, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21104971

RESUMO

BACKGROUND: Inhibition of tumor angiogenesis is a promising approach for cancer therapy and the Tie-2/angiopoietin pathway appears to play an important role. In the present study, we have developed strategies to explore the therapeutic potential of blocking the Tie-2/angiopoietin pathway by sTie-2. METHODS: Ehrlich ascites tumor (EAT) cells were stably transfected to overexpress a truncated form of sTie-2. Transfectants were characterized for their in vitro growth behavior and transplanted into nude mice. Furthermore, recombinant sTie-2 produced by the baculovirus expression system was used to sequester angiopoietins in the murine ascites carcinoma model. The effect of sTie-2 treatment alone or in combination with sFLT-1 on the weight of the animal, ascites cell number and volume was studied. RESULTS: EAT cells stably transfected with a truncated form of sTie-2 showed no change in cell proliferation in vitro and colony forming in soft agar compared to control cells. However, sTie-2 transfected EAT cells transplanted into nude mice reduced tumor burden and demonstrated a reduction in ascites formation and peritoneal angiogenesis. Recombinant sTie-2 showed angiogenic activity in the tube formation and wound healing assay in vitro. sTie-2 treatment alone or in combination with sFLT-1 in an ascites tumor mouse model resulted in reduced peritoneal angiogenesis, with a concomitant decrease in tumor cell number, volume of ascites and the number of invasive tumor cells, as assayed by CD31 staining. CONCLUSIONS: The findings of the present study demonstrate an important role for the Tie-2/angiopoietin pathway in the formation of tumor vasculature and suggest that sTie-2 might yield useful anticancer therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Ehrlich/patologia , Carcinoma de Ehrlich/terapia , Neovascularização Patológica/prevenção & controle , Receptor TIE-2/uso terapêutico , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/uso terapêutico , Angiopoietina-2 , Animais , Carcinoma de Ehrlich/metabolismo , Proliferação de Células/efeitos dos fármacos , Camundongos , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Receptor TIE-2/genética , Solubilidade , Transfecção/métodos , Transplantes , Resultado do Tratamento
17.
J Environ Qual ; 39(4): 1507-16, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20830937

RESUMO

Net nitrous oxide production and denitrification activity were measured in two mangrove ecosystems of Goa, India. The relatively pristine site Tuvem was compared to Divar, which is prone to high nutrient input. Stratified sampling at 2-cm intervals within the 0- to 10-cm depth range showed that N2O production at both the locations decreased with depth. Elevated denitrification activity at Divar resulted in maximum production of up to 1.95 nmol N2O-N g(-1) h(-1) at 2 to 4 cm, which was three times higher than at Tuvem. Detailed investigations to understand the major pathway contributing to N2O production performed at Tuvem showed that incomplete denitrification was responsible for up to 43 to 93% of N2O production. Nitrous oxide production rates closely correlated to nitrite concentration (n = 15; r = -0.47; p < 0.05) and denitrifier abundance (r = 0.55; p < 0.05), suggesting that nitrite utilization by microbial activity leads to N2O production. Nitrous oxide production through nitrification was below detection, affirming that denitrification is the major pathway responsible for production of the greenhouse gas. Net N2O production in these mangrove systems are comparatively higher than those reported from other natural estuarine sediments and therefore warrant mitigation measures.


Assuntos
Sedimentos Geológicos/química , Nitrogênio/metabolismo , Óxido Nitroso/metabolismo , Rhizophoraceae/fisiologia , Clima Tropical , Índia
18.
Environ Monit Assess ; 164(1-4): 81-92, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19353285

RESUMO

The HOBAS aeration system was tested to compare changes in environmental and bacteriological parameters in ponds growing Penaeus monodon during a single production cycle. The stocking density in the aerated pond was doubled to 12 post-larvae (PL) m(-2) in contrast to the non-aerated pond with 6 (PL) m(-2). Microbial abundance in the ponds ranged between 10(5-6) cells ml(-1). Among the physiological groups of bacteria enumerated, the heterotrophs dominated with an abundance of 10(4) CFU ml(-1). Of the nitrogen and sulfur cycle bacteria, the nitrifiers flourished in the aerated pond and could maintain ammonia-N concentration within permissible levels. Bacterial activity also maintained sulfide concentrations at < 0.03 mg l(-1). Non-aerated conditions promoted denitrification maintaining nitrate concentration between 0.32 and 0.98 microM NO(3)(-)-N l(-1). However, a marked increase in ammonium content was observed in the non-aerated pond at the end of the culture period. Thus in high-density ponds, the aerators served to stimulate bacterial growth and activity which consequently maintained the quality of the water to match that of low-density ponds. Accordingly, these aerators could be effectively used to sustain higher yields. The effluent from the aerated pond is less likely to alter the redox balance of the receiving waters.


Assuntos
Ar , Aquicultura , Microbiologia da Água , Água/química , Animais , Contagem de Colônia Microbiana , Crustáceos
19.
J Oral Biol Craniofac Res ; 10(4): 768-775, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33101891

RESUMO

OBJECTIVES: To present a comprehensive review of current literature available on Corona virus disease and dentistry, modifications required in dental and laboratory settings; and recommended disinfection protocols in current scenario. Special emphasis has been given to discuss guidelines for handling different prosthodontic procedures and implications of this pandemic on prosthodontic practice, education and research. MATERIALS AND METHODS: Relevant literature pertaining to COVID-19 and dentistry was scrutinized on electronic search engines including PubMed, EMBASE and Cochrane. Guidelines given by various organizations, institutions, national and international regulatory bodies and Indian Prosthodontic Society were also consulted to gather information pertaining to the objectives of our review. RESULTS: and observations: A total of 160 articles including cross-sectional studies, in vitro study, narrative reviews, letters to the editor and opinions were found to be relevant in accordance with our search strategy. Documented literature revealed that Covid-19 pandemic has culminated in serious clinical, financial and psychological implications in the field of dentistry. Certain steps such as adoption of teledentistry, judicious use of protective equipment, use of rubber dams, pre-procedural rinses have been suggested unanimously. However, there is a dearth of evidence-based recommendations in literature. Data regarding consequences of delaying prosthodontic procedures and patients' perspectives is also sparse. CONCLUSION: The COVID-19 necessitates the need to adopt a balanced approach while treating patients and safeguarding the dental professionals at the same time. Risk-benefit ratio has to be assessed along with stringent following of guidelines and disinfection protocols to combat this unprecedented situation.

20.
Biochim Biophys Acta ; 2008 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-19084052

RESUMO

This article has been withdrawn consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologizes for any inconvenience this may cause.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA