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1.
Planta ; 258(2): 37, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37405593

RESUMO

MAIN CONCLUSION: Nicotiana tabacum exhibits recovery response towards tomato leaf curl Gujarat virus. Transcriptome analysis revealed the differential expression of defense-related genes. Genes encoding for cysteine protease inhibitor, hormonal- and stress-related to DNA repair mechanism are found to be involved in the recovery process. Elucidating the role of host factors in response to viral infection is crucial in understanding the plant host-virus interaction. Begomovirus, a genus in the family Geminiviridae, is reported throughout the globe and is known to cause serious crop diseases. Tomato leaf curl Gujarat virus (ToLCGV) infection in Nicotiana tabacum resulted in initial symptom expression followed by a quick recovery in the systemic leaves. Transcriptome analysis using next-generation sequencing (NGS) revealed a large number of differentially expressed genes both in symptomatic as well as recovered leaves when compared to mock-inoculated plants. The virus infected N. tabacum results in alteration of various metabolic pathways, phytohormone signaling pathway, defense related protein, protease inhibitor, and DNA repair pathway. RT-qPCR results indicated that Germin-like protein subfamily T member 2 (NtGLPST), Cysteine protease inhibitor 1-like (NtCPI), Thaumatin-like protein (NtTLP), Kirola-like (NtKL), and Ethylene-responsive transcription factor ERF109-like (NtERTFL) were down-regulated in symptomatic leaves when compared to recovered leaves of ToLCGV-infected plants. In contrast, the Auxin-responsive protein SAUR71-like (NtARPSL) was found to be differentially down-regulated in recovered leaves when compared to symptomatic leaves and the mock-inoculated plants. Lastly, Histone 2X protein like (NtHH2L) gene was found to be down-regulated, whereas Uncharacterized (NtUNCD) was up-regulated in both symptomatic as well as recovered leaves compared to the mock-inoculated plants. Taken together, the present study suggests potential roles of the differentially expressed genes that might govern tobacco's susceptibility and/or recovery response towards ToLCGV infection.


Assuntos
Begomovirus , Geminiviridae , Solanum lycopersicum , Begomovirus/genética , Nicotiana/genética , Solanum lycopersicum/genética , Perfilação da Expressão Gênica , Doenças das Plantas/genética , Folhas de Planta/genética
2.
Bull Environ Contam Toxicol ; 111(3): 44, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37715801

RESUMO

Moyna of Purba Medinipur district is widely known as an aquaculture hub of West Bengal, India. Though very good production is achievable from this fish culture system, management practices are inappropriate, which could create the sustainability problem of this culture system. The present study was thus undertaken for the estimation of plankton population, water quality, carbon footprint and carbon sequestration of this intensive aquaculture practices. Information on spawn to fry, fry to fingerlings and grow-out culture were collected through the structured questionnaire from the fish farmers. The plankton density, primary productivity, carbon footprint and carbon sequestration were analyzed using standard procedures. The phytoplankton, zooplankton and primary productivity were maximum at the stocking period and minimum during the middle of culture period. The lowest feed conversion ratio (FCR) was noticed with the minimum amount of feed applied in the pond. The CO2-e emission ranged from 0.56 to 4.89 kg CO2-e/kg fish (av. 2.13) for the production levels of 5.0 to 10.7 t/ha/yr. The pond water developed salinity and ammonium-N increased from 0.01 to 0.50 mg/l. The ponds with high feed loading (28 to 32 t/ha/yr) had the highest average sediment accumulation rate (11.0 ± 3.0 cm/yr) and carbon sequestration (704 ± 30 g C/m2/yr).


Assuntos
Pegada de Carbono , Sequestro de Carbono , Animais , Dióxido de Carbono , Aquicultura , Índia , Plâncton
3.
Clin Exp Immunol ; 201(3): 279-288, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32443171

RESUMO

Solid tumors elicit suppressive T cell responses which impair antigen-presenting cell (APC) functions. Such immune suppression results in uncontrolled tumor growth and mortality. Addressing APC dysfunction, dendritic cell (DC)-mediated anti-tumor vaccination was extensively investigated in both mice and humans. These studies never achieved full resistance to tumor relapse. Herein, we describe a repetitive RM-1 murine tumor rechallenge model for recurrence in humans. Using this newly developed model, we show that priming with tumor antigen-pulsed, Toll-like receptor (TLR)2 ligand-activated DCs elicits a host-protective anti-tumor immune response in C57BL/6 mice. Upon stimulation with the TLR2 ligand peptidoglycan (PGN), the tumor antigen-pulsed DCs induce complete resistance to repetitive tumor challenges. Intra-tumoral injection of PGN reduces tumor growth. The tumor resistance is accompanied by increased expression of interleukin (IL)-27, T-box transcription factor TBX21 (T-bet), IL-12, tumor necrosis factor (TNF)-α and interferon (IFN)-γ, along with heightened cytotoxic T lymphocyte (CTL) functions. Mice primed four times with PGN-stimulated tumor antigen-pulsed DCs remain entirely resistant to repeat challenges with RM-1 tumor cells, suggesting complete prevention of relapse and recurrence of tumor. Adoptive transfer of T cells from these mice, which were fully protected from RM-1 rechallenge, confers anti-tumor immunity to syngeneic naive recipient mice upon RM-1 challenge. These observations indicate that PGN-activated DCs induce robust host-protective anti-tumor T cells that completely resist tumor growth and recurrence.


Assuntos
Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Imunoterapia Adotiva/métodos , Neoplasias da Próstata/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Citocinas/metabolismo , Células Dendríticas/transplante , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Recidiva Local de Neoplasia , Peptidoglicano/metabolismo , Receptor 2 Toll-Like/agonistas , Carga Tumoral
5.
Clin Exp Immunol ; 190(2): 167-186, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28708252

RESUMO

Toll-like receptors (TLRs) are germline-encoded, non-clonal innate immune receptors, which are often the first receptors to recognize the molecular patterns on pathogens. Therefore, the immune response initiated by TLRs has far-reaching consequences on the outcome of an infection. As soon as the cell surface TLRs and other receptors recognize a pathogen, the pathogen is phagocytosed. Inclusion of TLRs in the phagosome results in quicker phagosomal maturation and stronger adaptive immune response, as TLRs influence co-stimulatory molecule expression and determinant selection by major histocompatibility complex (MHC) class II and MHC class I for cross-presentation. The signals delivered by the TCR-peptide-MHC complex and co-stimulatory molecules are indispensable for optimal T cell activation. In addition, the cytokines induced by TLRs can skew the differentiation of activated T cells to different effector T cell subsets. However, the potential of TLRs to influence adaptive immune response into different patterns is severely restricted by multiple factors: gross specificity for the molecular patterns, lack of receptor rearrangements, sharing of limited number of adaptors that assemble signalling complexes and redundancy in ligand recognition. These features of apparent redundancy and regulation in the functioning of TLRs characterize them as important and probable contributory factors in the resistance or susceptibility to an infection.


Assuntos
Leishmania/imunologia , Leishmaniose/imunologia , Receptores Toll-Like/imunologia , Imunidade Adaptativa , Animais , Apresentação Cruzada , Regulação da Expressão Gênica , Humanos , Imunidade Inata , Camundongos , Moléculas com Motivos Associados a Patógenos/imunologia , Fagocitose , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/fisiologia , Receptores Toll-Like/classificação , Receptores Toll-Like/deficiência , Receptores Toll-Like/genética
6.
Lett Appl Microbiol ; 58(2): 184-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24118020

RESUMO

UNLABELLED: Assessment of antibacterial as well as antiherpes virus activity of sulfonoquinovosyldiacylglyceride (SQDG), a glycolipid, isolated from the leaves of Azadirachta indica has been described. Antimicrobial activity was evaluated against Gram-positive, Gram-negative bacteria and herpes simplex virus. SQDG showed significant inhibitory activity against Salmonella typhi and two isolates of Shigella dysenteriae with MIC values 32 µg ml(-1) , while three isolates of Salm. typhi, Escherichia coli and Vibrio cholerae were inhibited at 64 µg ml(-1) and have shown zone diameter ranging from 6.2 to 12.3 mm. The growth kinetics study of SQDG on Salm. typhi and Sh. dysenteriae revealed that the growths were completely inhibited at their MIC values within 24 h of exposure. Interestingly, SQDG inhibits herpes simplex virus (HSV) type 1 and 2 with the EC50 of 9.1 and 8.5 µg ml(-1) , compared with acyclovir (2.2 and 2.8 µg ml(-1) against HSV-1 and HSV-2). The selectivity index (SI) was found to be 12.4 against HSV-1 and 13.41 with HSV-2. Furthermore, the expression of proinflammatory cytokines of HSV-infected and SQDG-treated macrophages using ELISA kit revealed that SQDG significantly downregulated the production of TNF-α, IL-1ß, IL-12 and IL-6. SIGNIFICANCE AND IMPACT OF THE STUDY: The water-soluble metabolite sulfonoquinovosyldiacylglyceride (SQDG) isolated from Azadirachta indica (Neem) possess significant antibacterial as well as anti-HSV activity. The efficacies as well as the solubility factor of SQDG substantiate a greater attention for its use as phytotherapeutic drug for controlling microbial infections as most consumers have better acceptance of phytomedicines than synthetic drugs.


Assuntos
Antibacterianos/farmacologia , Antivirais/farmacologia , Azadirachta/química , Glicolipídeos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Simplexvirus/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antivirais/química , Antivirais/isolamento & purificação , Citocinas/metabolismo , Enterobacteriaceae/efeitos dos fármacos , Glicolipídeos/química , Glicolipídeos/isolamento & purificação , Bactérias Gram-Negativas/crescimento & desenvolvimento , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento , Vibrio cholerae/efeitos dos fármacos , Vibrio cholerae/crescimento & desenvolvimento , Ensaio de Placa Viral
7.
Artigo em Inglês | MEDLINE | ID: mdl-24316823

RESUMO

Poxvirus uracil DNA glycosylases are the most diverse members of the family I uracil DNA glycosylases (UNGs). The crystal structure of the uracil complex of Vaccinia virus uracil DNA glycosylase (D4) was determined at 2.03 Å resolution. One uracil molecule was located in the active-site pocket in each of the 12 noncrystallographic symmetry-related D4 subunits. Although the UNGs of the poxviruses (including D4) feature significant differences in the characteristic motifs designated for uracil recognition and in the base-excision mechanism, the architecture of the active-site pocket in D4 is very similar to that in UNGs of other organisms. Overall, the interactions of the bound uracil with the active-site residues are also similar to the interactions previously observed in the structures of human and Escherichia coli UNG.


Assuntos
Modelos Moleculares , Subunidades Proteicas/química , Uracila-DNA Glicosidase/química , Uracila/química , Vaccinia virus/química , Proteínas Virais/química , Domínio Catalítico , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Humanos , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia Estrutural de Proteína , Uracila/metabolismo , Uracila-DNA Glicosidase/genética , Uracila-DNA Glicosidase/metabolismo , Vaccinia virus/enzimologia , Vaccinia virus/genética , Proteínas Virais/genética , Proteínas Virais/metabolismo
8.
J Appl Microbiol ; 115(6): 1317-28, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23957446

RESUMO

AIM: To evaluate the in vitro antimicrobial activity of aqueous and methanol extracts of Odina wodier bark (OWB), a folk medicine, against representative bacteria, fungi and herpes simplex virus (HSV) associated with skin infections. METHODS AND RESULTS: The OWB extract(s) was found to inhibit the isolates of Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Klebsiella pneumonia, Escherichia coli at an MIC of 256-5000 µg ml(-1) and Candida albicans at and above 4000 µg ml(-1) by agar and broth dilution assays. The growth curve of Staph. aureus revealed the highest activity within 2-6 h of methanol extract (ME) exposure. Interestingly, the MTT and plaque reduction assay showed that the extracts can inhibit HSV-1 and HSV-2 at EC50 of 22·4 and 28·8 µg ml(-1) , with Selectivity index of 11·7-15. While the time kinetic and binding assays demonstrated that the ME at 50 µg ml(-1) prevents viral attachment into Vero cells. Phytochemical and HPLC analysis of ME revealed the presence of flavonoids, phytosterols, saponins and tannins including the pseudotannin chlorogenic acid. CONCLUSION: The traditional use of OWB for the management of skin infections has scientific basis. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrated the antimicrobial potential of OWB on selected isolates of bacteria, fungi and HSV, associated with skin infections.

9.
Int J Infect Dis ; 113: 119-124, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34601144

RESUMO

OBJECTIVES: Following the Public Health Emergency of International Concern declared on Zika by the World Health Organization during 2016, the Indian Council of Medical Research carried out nationwide vector surveillance for Zika and Dengue viruses (ZIKV and DENV) in India as a preparedness measure in 2016-19. METHODS: High-risk zones distributed to 49 Districts in 14 states/union territories were included in the study. Seven ICMR institutions participated, following a standard operating protocol. Aedes specimens sampled weekly were processed by multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) for ZIKV/DENV and random samples crosschecked with real-time RT-PCR for ZIKV. RESULTS: Altogether, 79 492 Aedes specimens in 6492 pools were processed; 3 (0.05%) and 63 (0.97%) pools, respectively, were found positive for ZIKV and DENV. ZIKV infections were recorded in Aedes aegypti sampled during the 2018 sporadic Zika outbreak in Jaipur, Rajasthan. However, these belonged to the Asian lineage of the virus, already circulating in the country. Both Ae. aegypti and Aedes albopictus distributed to 8 states/union territories were found to be infected with DENV. Both sexes of Ae. albopictus were infected, indicating transovarial transmission. CONCLUSION: This investigation evinced no active transmission of the American lineage-pandemic Zika virus in India during the pandemic period.


Assuntos
Aedes , Dengue , Infecção por Zika virus , Zika virus , Animais , Dengue/epidemiologia , Feminino , Humanos , Índia/epidemiologia , Masculino , Mosquitos Vetores , Pandemias , Infecção por Zika virus/epidemiologia
10.
Inorg Chem ; 49(7): 3121-9, 2010 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-20192227

RESUMO

A new dinuclear nickel(II) complex, [Ni(2)(LH(2))(H(2)O)(2)(OH)(NO(3))](NO(3))(3) (1), of an "end-off" compartmental ligand 2,6-bis(N-ethylpiperazine-iminomethyl)-4-methyl-phenolato, has been synthesized and structurally characterized. The X-ray single crystal structure analysis shows that the piperazine moieties assume the expected chair conformation and are protonated. The complex 1 exhibits versatile catalytic activities of biological significance, viz. catecholase, phosphatase, and DNA cleavage activities, etc. The catecholase activity of the complex observed is very dependent on the nature of the solvent. In acetonitrile medium, the complex is inactive to exhibit catecholase activity. On the other hand, in methanol, it catalyzes not only the oxidation of 3,5-di-tert-butylcatechol (3,5-DTBC) but also tetrachlorocatechol (TCC), a catechol which is very difficult to oxidize, under aerobic conditions. UV-vis spectroscopic investigation shows that TCC oxidation proceeds through the formation of an intermediate. The intermediate has been characterized by an electron spray ionizaton-mass spectrometry study, which suggests a bidentate rather than a monodentate mode of TCC coordination in that intermediate, and this proposition have been verified by density functional theory calculation. The complex also exhibits phosphatase (with substrate p-nitrophenylphosphate) and DNA cleavage activities. The DNA cleavage activity exhibited by complex 1 most probably proceeds through a hydroxyl radical pathway. The bioactivity study suggests the possible applications of complex 1 as a site specific recognition of DNA and/or as an anticancer agent.


Assuntos
Níquel/química , Piperazinas/química , Cristalografia por Raios X , DNA/química , Modelos Moleculares , Oxirredução
11.
J Cell Biol ; 149(2): 281-92, 2000 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-10769022

RESUMO

During differentiation, skeletal muscle cells withdraw from the cell cycle and fuse into multinucleated myotubes. Unlike quiescent cells, however, these cells cannot be induced to reenter S phase by means of growth factor stimulation. The studies reported here document that both the retinoblastoma protein (Rb) and the cyclin-dependent kinase (cdk) inhibitor p21 contribute to this unresponsiveness. We show that the inactivation of Rb and p21 through the binding of the adenovirus E1A protein leads to the induction of DNA replication in differentiated muscle cells. Moreover, inactivation of p21 by E1A results in the restoration of cyclin E-cdk2 activity, a kinase made nonfunctional by the binding of p21 and whose protein levels in differentiated muscle cells is relatively low in amount. We also show that restoration of kinase activity leads to the phosphorylation of Rb but that this in itself is not sufficient for allowing differentiated muscle cells to reenter the cell cycle. All the results obtained are consistent with the fact that Rb is functioning downstream of p21 and that the activities of these two proteins may be linked in sustaining the postmitotic state.


Assuntos
Proteínas E1A de Adenovirus/metabolismo , Quinases relacionadas a CDC2 e CDC28 , Diferenciação Celular/fisiologia , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Replicação do DNA/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteína do Retinoblastoma/metabolismo , Animais , Linhagem Celular , Sistema Livre de Células , Ciclina E/metabolismo , Quinase 2 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p21 , Quinases Ciclina-Dependentes/antagonistas & inibidores , Camundongos , Músculo Esquelético/citologia , Músculo Esquelético/fisiologia , Mutagênese , Proteínas Recombinantes/metabolismo , Transfecção
12.
Lett Appl Microbiol ; 48(5): 593-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19416461

RESUMO

AIMS: The present study was aimed at finding the optimal conditions for the production of pectate lyase using immobilized Bacillus pumilus DKS1 cells in calcium-alginate (Ca-alginate) beads and determining the efficient degumming of ramie fibre. METHODS AND RESULTS: The active cells of B. pumilus DKS1 were immobilized in Ca-alginate and used for the production of pectate lyase. The production of enzyme increased significantly with increasing alginate concentration and reached a maximum enzyme yield of 38.5 U ml(-1) at 18 g l(-1). This was about 1.5-fold higher than that obtained by free cells. Degummed fibre using immobilized cells showed better tenacity than that prepared by using nonimmobilized cells. CONCLUSIONS: The Ca-alginate entrapment is a promising immobilization method of B. pumilus DKS1 for semicontinuous enzyme production. Enzyme production by immobilized cells is superior to that of free cells because it leads to higher volumetric activities within the same period of fermentation. Fibre degumming by using immobilized cells produced better quality fibre. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of degumming of fibre using enzyme from immobilized B. pumilus cells as per our knowledge. High-quality degummed fibre could be prepared with relatively inexpensive inputs for use in the textile and paper industry.


Assuntos
Bacillus/enzimologia , Proteínas de Bactérias/metabolismo , Boehmeria/metabolismo , Microbiologia Industrial , Gomas Vegetais/metabolismo , Polissacarídeo-Liases/metabolismo , Proteínas de Bactérias/química , Boehmeria/química , Células Imobilizadas/química , Células Imobilizadas/enzimologia , Cinética , Polissacarídeo-Liases/química
13.
Proteins ; 73(4): 889-901, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18536013

RESUMO

We have employed a structure-based three-dimensional quantitative structure-activity relationship (3D-QSAR) approach to predict the biochemical activity for inhibitors of T. cruzi dihydrofolate reductase-thymidylate synthase (DHFR-TS). Crystal structures of complexes of the enzyme with eight different inhibitors of the DHFR activity together with the structure in the substrate-free state (DHFR domain) were used to validate and refine docking poses of ligands that constitute likely active conformations. Structural information from these complexes formed the basis for the structure-based alignment used as input for the QSAR study. Contrary to indirect ligand-based approaches the strategy described here employs a direct receptor-based approach. The goal is to generate a library of selective lead inhibitors for further development as antiparasitic agents. 3D-QSAR models were obtained for T. cruzi DHFR-TS (30 inhibitors in learning set) and human DHFR (36 inhibitors in learning set) that show a very good agreement between experimental and predicted enzyme inhibition data. For crossvalidation of the QSAR model(s), we have used the 10% leave-one-out method. The derived 3D-QSAR models were tested against a few selected compounds (a small test set of six inhibitors for each enzyme) with known activity, which were not part of the learning set, and the quality of prediction of the initial 3D-QSAR models demonstrated that such studies are feasible. Further refinement of the models through integration of additional activity data and optimization of reliable docking poses is expected to lead to an improved predictive ability.


Assuntos
Biologia Computacional , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Relação Quantitativa Estrutura-Atividade , Tetra-Hidrofolato Desidrogenase/metabolismo , Trypanosoma cruzi/enzimologia , Animais , Sítios de Ligação , Antagonistas do Ácido Fólico/química , Antagonistas do Ácido Fólico/farmacologia , Humanos , Ligantes , Metotrexato/química , Modelos Moleculares , Análise de Regressão , Trypanosoma cruzi/efeitos dos fármacos
14.
J Am Chem Soc ; 130(15): 5185-93, 2008 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-18335991

RESUMO

An efficient synthesis of a family of heteroaromatic triazinium compounds, [2a]X-[2g]X (X = Cl, ClO4, NO3, and HSO4), from 2-(arylazo)pyridines via proton-catalyzed heterocyclization is described. Characterization of the compounds is made by different spectroscopic, electrochemical techniques, as well as single-crystal structure determination of the triflate salt of a representative compound, [2a]CF3SO3. The bond parameters indicate that the tricyclo compound, 2a(+), is planar and aromatic with a N-N bond length of 1.275(6) A. These exhibited fluorescence with an emission maximum in the range of 540-535 nm with moderate quantum yields. The triazinium salts can be reduced in two successive one-electron steps as probed by cyclic voltammetry and coulometry. The paramagnetic radical intermediate 2a(*) is distinguished by a sharp and intense EPR spectrum. Fluorescence spectroscopy, circular dichroism, cyclic voltammetry, viscosity measurements, together with DNA melting studies have been used to characterize the binding of 2a(+) with calf thymus DNA. The emission quenching of the compound by [Fe(CN)6](4-) decreased when bound to DNA. As determined by a MTT assay, 2a(+) exhibited significant cytotoxicity at a higher concentration range of 1 mg/mL to 1 microg/mL; however, the % survival ratio increased with dilution. Cellular uptake studies of the referenced compound were followed by FACS analysis.


Assuntos
Compostos Azo/química , DNA/química , Piridinas/química , Animais , Compostos Azo/síntese química , Compostos Azo/toxicidade , Cátions/química , Bovinos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Dicroísmo Circular , Cristalografia por Raios X , Ciclização , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Modelos Moleculares , Estrutura Molecular , Oxirredução , Espectrofotometria , Viscosidade
15.
Environ Monit Assess ; 136(1-3): 299-306, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17370129

RESUMO

A study was conducted to determine the effect of metals on soil microbial biomass and activities in landfill soils as well as normal background soil. The microbial biomass and activities were consistently higher in the landfill soils than in the background soil. Significant positive correlations existed between the microbial parameters and soil organic carbon. The landfill soils contained higher concentrations of metals (iron, manganese, copper, cadmium, lead and zinc) than did the background soil. Microbial parameters were negatively correlated with the metals, with inhibition increasing with the bioavailability of the metals. It is suggested that the metals affected microbial biomass and activities by behaving synergistically or additively with each other. Although the landfill soils had higher microbial biomass and activities than the background soil, due to higher organic matter content, the ratios of microbial parameters/organic carbon indicated that inhibition of microbial growth and activities had occurred due to metal stress.


Assuntos
Biomassa , Metais Pesados/análise , Eliminação de Resíduos , Microbiologia do Solo , Poluentes do Solo/análise , Solo/análise , Biodegradação Ambiental , Carbono/análise , Humanos , Índia , Fatores de Tempo
16.
Ann Burns Fire Disasters ; 30(2): 143-145, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-29021728

RESUMO

Facial units reconstruction in a post burn patient poses tough challenges. Simultaneous brow and lid reconstruction is one of them. This article presents a 45-year-old epileptic male with burn of complete face. The task of reconstructing the brow, upper and lower lids was successfully accomplished using a modification of the Guyuron postauricular fasciocutaneous flap, after initial grafting and radial forearm flap reconstruction of forehead and other parts of the face. The article gives a single-stop solution for simultaneous reconstruction of brow and lids using a random pattern extension of the traditional postauricular flap, thus proving the excellent vascularity and hence durability of the flap in spite of a 180 degrees change in the orientation of the flap with respect to the axis.


La reconstruction des unités esthétiques de la face dans les séquelles de brûlures constitue un grand défi. La reconstruction simultanée du front et des paupières en fait partie. Il s'agit de l'observation d'une brûlure pan faciale chez un homme épileptique de 45 ans. L'objectif de reconstruction du front et des quatre paupières fut atteint avec succès, en utilisant une modification du lambeau fascio cutané rétro auriculaire de Guyuron, réalisé secondairement, à la suite de gestes itératifs : greffe initiale après détersion, réparation du front par un lambeau pédiculé ante brachial radial, et greffes d'autres parties du visage. L'article propose ainsi une solution idéale pour la reconstruction simultanée du front et des paupières en utilisant l'extension du lambeau au hasard qu'est le lambeau traditionnel rétro auriculaire, celui-ci garantissant une excellente vascularisation et ainsi sa pérennité, malgré un changement d'orientation de 180° en respectant son axe.

18.
World J Gastroenterol ; 11(14): 2171-3, 2005 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-15810087

RESUMO

AIM: To determine the outcome of polypoidal lesions within the gall bladder (PLG) diagnosed by trans-abdominal scanning. METHODS: A nine-year (1993-2002) retrospective case-note review of all patients who underwent ultrasound scanning after referral to a single Upper GI Surgeon at a District General Hospital was conducted. Patients who were diagnosed with a PLG were included in our study. A database was constructed and patient details, investigations including ultrasound scan (USS) findings, treatment and histology and final diagnosis were recorded. RESULTS: Twenty-three (out of 651) patients were diagnosed pre-operatively by USS to have a polyp-like gall bladder lesion (PLG). Post cholecystectomy histological examination revealed 12 gallstones, 7 cholesterol polyps, 3 adenocarcinomas within polyps and 1 normal gall bladder. The specificity of USS in the diagnosis of PLG was 92.3%. All the true polyps were malignant. Overall USS had 66.66% sensitivity and 100% specificity in the pre-operative suspicion of malignancy. Using size greater than 10 mm as measured on USS as a cut-off, we find 100% sensitivity and 86.95% specificity with a positive predictive value of 50% in the diagnosis of malignancy in PLG. CONCLUSION: A large number of PLG are in fact calculi within diseased gall bladder. In cases of gall bladder polyps more then 10 mm in size on USS further imaging (cross-sectional and/or EUS) is indicated prior to surgery. This will help in the optimal management of patients and avoid histological surprises.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Pólipos/diagnóstico por imagem , Adenocarcinoma/cirurgia , Colecistectomia , Feminino , Neoplasias da Vesícula Biliar/cirurgia , Cálculos Biliares/diagnóstico por imagem , Cálculos Biliares/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos/cirurgia , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia
19.
J Nanosci Nanotechnol ; 5(2): 209-28, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15853139

RESUMO

Several techniques were recently reported for the bulk separation of metallic (M) and semiconducting (S) single wall carbon nanotubes (SWNTs), using optical absorption and resonance Raman spectroscopy (RRS) as a proof of the separation. In the present work, we develop a method for the quantitative evaluation of the M to S separation ratio, and also for the SWNT diameter selectivity of the separation process, based on RRS. The relative changes in the integrated intensities of the radial-breathing mode (RBM) features, with respect to the starting material, yield the diameter probability distribution functions for M and S SWNTs in the separated fractions, accounting for the different resonance conditions of individual SWNTs, while the diameter distribution of the starting material is obtained following the fitting procedure developed by Kuzmany and coworkers. Features other than the RBM are generally less effective for characterization of the separation process for SWNTs.


Assuntos
Metais/química , Nanotubos de Carbono/química , Análise Espectral Raman/métodos , Nanotecnologia/métodos
20.
Protein Sci ; 9(4): 704-12, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10794412

RESUMO

Human infection with Toxoplasma gondii is an important cause of morbidity and mortality. Protozoan parasites such as T. gondii are incapable of de novo purine biosynthesis and must acquire purines from their host, so the purine salvage pathway offers a number of potential targets for antiparasitic chemotherapy. In T. gondii tachyzoites, adenosine is the predominantly salvaged purine nucleoside, and thus adenosine kinase is a key enzyme in the purine salvage pathway of this parasite. The structure of T. gondii adenosine kinase was solved using molecular replacement and refined by simulated annealing at 1.8 A resolution to an R-factor of 0.214. The overall structure and the active site geometry are similar to human adenosine kinase, although there are significant differences. The T. gondii adenosine kinase has several unique features compared to the human sequence, including a five-residue deletion in one of the four linking segments between the two domains, which is probably responsible for a major change in the orientation of the two domains with respect to each other. These structural differences suggest the possibility of developing specific inhibitors of the parasitic enzyme.


Assuntos
Adenosina Quinase/química , Toxoplasma/enzimologia , Adenosina/metabolismo , Adenosina Quinase/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Cloretos/metabolismo , Cristalografia por Raios X , Humanos , Magnésio/metabolismo , Dados de Sequência Molecular , Conformação Proteica , Homologia de Sequência de Aminoácidos
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