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2.
Nanoscale ; 7(41): 17195-210, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26439751

RESUMO

Copper nanowires (Cu NWs) are of particular interest for application as transparent and flexible conducting electrodes in 'see-through' and/or 'deformable' future electronics due to their excellent electrical, optical, and mechanical properties. It is necessary to develop reliable and facile methods to produce well-defined Cu NWs prior to their full exploitation. Among the wide variety of methods available to generate Cu NWs, solution-based synthesis routes are considered to be a promising strategy because of several advantages including fewer constraints on the selection of precursors, the solvent and reaction conditions, and the feasibility of large-scale low-cost production. Here, we provide a thorough review of various recently developed synthetic methodologies to obtain Cu NWs, with particular emphasis on wet chemical synthesis approaches including a hydrothermal route, reduction of metal precursors, and catalytic synthesis. The emerging applications of Cu NWs including transparent electrodes and flexible/stretchable electronics are also discussed, followed by brief comments on the remaining challenges and future research perspectives.

3.
Phys Chem Chem Phys ; 16(40): 22107-15, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25209426

RESUMO

Ligands/surfactants play an important role in the synthesis of anisotropic nanomaterials. Other than site specific binding to the crystal plane, they can also undergo complexation with metal ions, altering the nature of the metal complex. The ligand-metal complex formation could be sufficient to modify the reaction kinetics and could affect the size and morphology of the nanostructures. In this article, we investigated such a change in the metal precursor caused by ligands (i.e., alkyl amines) in the hydrothermal synthesis of Cu nanowires in the presence of glucose as a reducing agent. Comparative studies were carried out with other nitrogen-based surfactants such as cetyl trimethyl ammonium bromide and polyvinyl pyrrolodine. Our experimental results confirmed the complex formation of Cu(2+) ions with alkyl amines and its application for nanowire synthesis. Slow reduction of this complex allows for the generation of twinned seeds, which are later grown into nanowires by consuming newly generated seeds in the presence of excess alkyl amine.

4.
Curr Oncol ; 17(5): 63-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20975881

RESUMO

According to the published data, most primary central nervous system lymphomas (PCNSLs) are B-cell lymphomas; primary T-cell lymphomas are rare. In a search of the MEDLINE database, we found only 6 cases of primary T-cell PCNSL. Here, we present the case of a 43-year-old man with AIDS, not on highly active antiretroviral therapy, who presented with focal neurologic symptoms and was found on magnetic resonance imaging to have multiple brain lesions. A biopsy showed T-cell lymphoma, and the patient was subsequently treated with whole-brain radiation, to marked clinical response. Reported cases from the literature of primary T-cell PCNSL in AIDS patients are summarized in this review.

5.
Afr J Tradit Complement Altern Med ; 4(4): 481-7, 2007 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-20161916

RESUMO

Anthocephalus cadamba (Roxb.) Miq. Syn A. chinensis (Lamk) A. Rich (Rubiaceae) is ethnomedicinally widely used in the form of paste by tribe in western Ghats for treating skin diseases. In this context, antimicrobial potential of A. cadamba against a wide range of microorganisms was studied. To validate the ethnotherapeutic claims of the plant in skin diseases, wound healing activity was studied, besides antioxidant activity to understand the mechanism of wound healing. The alchoholic and aqueous extract of this plant showed significant antibacterial and antifungal activity against almost all the organisms: Micrococcus luteus, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, and four fungi Candida albicans, Trichophyton rubrum--dermatophyte fungi, Aspergillus niger, Aspergillus flavus and Aspergillus nidulans--systemic fungi, with especially good activity against the dermatophyte (Trichophyton rubrum) and some infectious bacteria (Escherichia coli, Proteus mirabilis and Staphylococcus aureus) with an MIC of 2.5 microg/disc. The results show that A. cadamba extract has potent wound healing capacity as shown from the wound contraction and increased tensile strength. The results also indicated that A. cadamba extract possesses potent antioxidant activity by inhibiting lipid peroxidation and increase in the superoxide dismutase (SOD) and catalase activity.

6.
Artigo em Inglês | MEDLINE | ID: mdl-15689070

RESUMO

Night mass blood surveys were carried out for parasitological evidence of Bancroftian filariasis in 45 rural areas belonging to 9 National Filaria Control Program (NFCP) zones of East Godavari and West Godavari districts of Andhra Pradesh, India during the period 1998 to 2001. Mf prevalence range between 2.9 to 10.2%, and mf intensities in 20 mm3 blood samples ranged from 1-281. The present study explains the trend of microfilaria dynamics in the rural population, where mass drug delivery has been implemented since 1997, and anti-larivicidal and adulticidal control measures have not been adopted.


Assuntos
Filariose/epidemiologia , Wuchereria bancrofti/isolamento & purificação , Adolescente , Adulto , Distribuição por Idade , Idoso , Animais , Criança , Pré-Escolar , Controle de Doenças Transmissíveis/métodos , Filariose/sangue , Filariose/prevenção & controle , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , Microfilárias/isolamento & purificação , Pessoa de Meia-Idade , Controle de Mosquitos , Prevalência , Saúde da População Rural , Clima Tropical
7.
Artigo em Inglês | MEDLINE | ID: mdl-15689071

RESUMO

The aim of the present investigation was to assess the filarial transmission levels in houses of different structure in rural areas of Andhra Pradesh, India. During this study, ecologically-similar households were selected for entomological study. The per-man-hour density (PMHD), infection and infectivity rates, were recorded in different ranges ie, 16.1 to 77.6, 0-31.2% and 0-5.6%, respectively.


Assuntos
Culex/parasitologia , Filariose Linfática/transmissão , Habitação/classificação , Insetos Vetores/parasitologia , Análise de Variância , Animais , Materiais de Construção , Filariose Linfática/parasitologia , Feminino , Inquéritos Epidemiológicos , Humanos , Umidade , Índia/epidemiologia , Fatores de Risco , Saúde da População Rural , Estações do Ano , Temperatura
8.
Indian J Biochem Biophys ; 39(6): 377-81, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22905394

RESUMO

Phospholipid-dependent, Ca(2+)-independent isoenzymes termed novel protein kinase C or nPKC, include PKC delta, epsilon, eta, theta and mu. Status and role of nPKC and PKC theta in Duchenne muscular dystrophic (DMD) condition is unknown. In the present study, we have shown that most of the nPKC isoforms are translocated to the membrane fraction of DMD tissue specimen. It is well established that translocation plays a key role in signal transduction by individual PKC isoforms. In our experiment, the increased association of nPKC isoform PKC theta to membrane was further confirmed by Western blot. Increased expression of PKC theta mRNA was identified by dot blot analysis. The above results suggest that, the alterations in nPKC location and increased expression of PKC theta observed is a result of modification of PKC-mediated signal transduction and cell function.


Assuntos
Isoenzimas/biossíntese , Músculos/metabolismo , Distrofia Muscular de Duchenne/metabolismo , Proteína Quinase C/metabolismo , Densitometria/métodos , Relação Dose-Resposta a Droga , Humanos , Isoenzimas/química , Isoenzimas/metabolismo , Isoformas de Proteínas , Proteína Quinase C/biossíntese , Proteína Quinase C-theta , RNA/química , Transdução de Sinais , Frações Subcelulares/metabolismo , Distribuição Tecidual
9.
Artigo em Inglês | MEDLINE | ID: mdl-12757213

RESUMO

This paper describes the seasonal abundance of Culex quinquefasciatus in the rural and urban areas of the East and West Godavari districts (EGDT and WGDT) of Andhra Pradesh, India. The per man-hour density (PMHD) was collected from seven units in EGDT and two units in WGDT, which comprised rural and urban areas. The highest infection and infectivity rates were found in the rural areas of Rajahmundry (43.6%) and Amalapuram (13.2%) respectively. In urban areas, the highest infection and infectivity rates were found in Rajahmundry: 7.5% and 3.6% respectively. There was considerable difference in the infection rate and infectivity rates between the rural areas and urban areas in each unit.


Assuntos
Culex/parasitologia , Doenças Endêmicas/estatística & dados numéricos , Filariose/epidemiologia , Insetos Vetores/parasitologia , Saúde da População Rural/estatística & dados numéricos , Estações do Ano , Saúde da População Urbana/estatística & dados numéricos , Wuchereria bancrofti , Análise de Variância , Animais , Feminino , Filariose/parasitologia , Filariose/prevenção & controle , Filariose/transmissão , Humanos , Índia/epidemiologia , Controle de Mosquitos , Avaliação das Necessidades , Densidade Demográfica , Vigilância da População , Prevalência , Fatores de Risco , Água/parasitologia
10.
Biochim Biophys Acta ; 1381(1): 104-12, 1998 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-9659377

RESUMO

Taxol is perhaps the most successful drug used for the treatment of various cancers. Comprehensive literature accumulated on therapeutics of the drug has indicated numerous side effects. In this paper, by use of fluorescence spectroscopy, it is shown that taxol binds to DNA with an affinity constant (Ka) of 1.08 x 10(7) M-1. This binding is accompanied by a large 'red edge excitation shift' (REES) of fluorescence emission maximum in taxol-DNA complex. The results point to an interaction of taxol with its core eight-membered ring in the DNA groove and the three phenyl rings projecting away from the DNA. The drug encompasses about two base pairs of DNA upon binding to it. Systematic studies with taxol analogues confirms such a mode of binding. These interesting findings on hitherto unknown taxol-DNA interactions may have clinical implications in view of its large number of side effects and pharmacokinetics.


Assuntos
Antineoplásicos Fitogênicos/metabolismo , DNA/metabolismo , Paclitaxel/metabolismo , Dicroísmo Circular , DNA/biossíntese , DNA/química , Espectrometria de Fluorescência
11.
Clin Chim Acta ; 269(1): 13-20, 1998 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-9498100

RESUMO

In order to measure the amount of m-calpain in platelets from Duchenne muscular dystrophy (DMD) patients, carriers and controls, an enzyme linked immunosorbent assay (ELISA) has been developed using polyclonal antibodies raised against m-calpain (Calcium dependent neutral protease), purified from human placenta. Compared to controls a nine-fold increase in the level of m-calpain was observed in all 25 DMD patients and eight obligate carrier mothers studied. Serum creatine kinase (SCK) values of four of these obligate carriers were found to be overlapping with that of normal values, limiting its usefulness. Since calpain levels were found to be raised in all DMD patients and obligate carriers, the estimation of calpain in all female relatives of the ones affected with DMD (with or without raised serum CK) would prove a facile index. Population screening for carrier females using this cost and labour effective index may help in assessing the carrier status and counselling the at risk families.


Assuntos
Plaquetas/metabolismo , Calpaína/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Triagem de Portadores Genéticos , Distrofias Musculares/sangue , Distrofias Musculares/genética , Adolescente , Adulto , Calpaína/isolamento & purificação , Criança , Ensaio de Imunoadsorção Enzimática/economia , Ensaio de Imunoadsorção Enzimática/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Sensibilidade e Especificidade
13.
J Virol ; 65(12): 6495-508, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1658356

RESUMO

An important question in feline leukemia virus (FeLV) pathogenesis is whether, as in murine leukemia virus infection, homologous recombination between the infecting FeLV and the noninfectious endogenous FeLV-like proviruses serves as a significant base for the generation of proximal pathogens. To begin an analysis of this issue, several recombinant FeLVs were produced by using two different approaches: (i) the regions of the viral envelope (env) gene of a cloned FeLV (subgroup B virus [FeLV-B], Gardner-Arnstein strain) and those of two different endogenous proviral loci were exchanged to create specific FeLV chimeras, and (ii) vectors containing endogenous env and molecularly cloned infectious FeLV-C (Sarma strain) DNA sequences were coexpressed by transfection in nonfeline cells to facilitate recombination. The results of these combined approaches showed that up to three-fourths of the envelope glycoprotein (gp70), beginning from the N-terminal end, could be replaced by endogenous FeLV sequences to produce biologically active chimeric FeLVs. The in vitro replication efficiency or cell tropism of the recombinants appeared to be influenced by the amount of gp70 sequences replaced by the endogenous partner as well as by the locus of origin of the endogenous sequences. Additionally, a characteristic biological effect, aggregation of feline T-lymphoma cells (3201B cell line), was found to be specifically induced by replicating FeLV-C or FeLV-C-based recombinants. Multiple crossover sites in the gp70 protein selected under the conditions used for coexpression were identified. The results of induced coexpression were also supported by rapid generation of FeLV recombinants when FeLV-C was used to infect the feline 3201B cell line that constitutively expresses high levels of endogenous FeLV-specific mRNAs. Furthermore, a large, highly conserved open reading frame in the pol gene of an endogenous FeLV provirus was identified. This observation, particularly in reference to our earlier finding of extensive mutations in the gag gene, reveals a target area for potentially productive homologous recombination upstream of the functional endogenous env gene.


Assuntos
DNA Viral/genética , Genes Virais , Genes env , Vírus da Leucemia Felina/genética , Recombinação Genética , Transfecção , Proteínas do Envelope Viral/genética , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Divisão Celular , Linhagem Celular , Quimera , Clonagem Molecular , Produtos do Gene pol/genética , Genes pol , Humanos , Cinética , Vírus da Leucemia Felina/fisiologia , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Provírus/genética , Provírus/fisiologia , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico
14.
Neurosurgery ; 24(5): 762-4, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2541370

RESUMO

Intraorbital paragangliomas are rare. A case of intraorbital paraganglioma with extension to the middle cranial fossa is reported. Progressive throbbing, hemicranial headaches, unilateral proptosis, and visual failure are the presenting symptoms. The computed tomographic and operative findings suggested a meningioma. Surgical removal of the tumor resulted in total relief of symptoms and recovery of vision. The pathogenesis and pathological findings are discussed.


Assuntos
Neoplasias Orbitárias/patologia , Paraganglioma Extrassuprarrenal/patologia , Adulto , Feminino , Humanos , Invasividade Neoplásica , Neoplasias Orbitárias/diagnóstico por imagem , Paraganglioma Extrassuprarrenal/diagnóstico por imagem , Tomografia Computadorizada por Raios X
15.
J Virol ; 63(5): 2379-84, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2539525

RESUMO

Nucleotide sequence analysis of the env gene of two different endogenous feline leukemia virus (FeLV) loci, CFE-6 and CFE-16, of domestic cats revealed the following characteristics. (i) Both proviruses contain an open reading frame in the env region; (ii) whereas the full complement of the exogenous FeLV env is generally present in CFE-6 DNA, it is truncated in CFE-16 DNA such that the 5' half of the gp70 domain and the untranslated region 3' to the p15E domain have been fused by an internal deletion, resulting in loss of the C-terminal half of the gp70- and all of the p15E-coding sequences; (iii) endogenous env is highly homologous to large sequence domains conserved in all three exogenous FeLV subgroups (A, B, and C) but is similar to FeLV-B sequence domains in the variable regions detected in these viruses; and (iv) there are four other sequence domains, one residing at the C terminus of gp70 and three scattered in p15E, which are unique for the endogenous env, thereby distinguishing it from the FeLV-B gene.


Assuntos
Genes Virais , Vírus da Leucemia Felina/genética , Provírus/genética , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Sequência de Bases , DNA Viral/genética , Dados de Sequência Molecular , Solubilidade , Proteínas do Envelope Viral/ultraestrutura
16.
J Virol ; 62(10): 3631-41, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2843665

RESUMO

The nucleotide sequence of the 5' long terminal repeat (LTR) of three independent loci (CFE-6, CFE-16, and CF-14) of endogenous feline leukemia virus (FeLV) DNAs of the domestic cat genome was determined. The 3' LTR of the CFE-6 clone was also sequenced. The endogenous FeLV LTRs, which were very similar to each other in sequence and in organization of the functional domains, differed considerably from the exogenous FeLV LTR in the U3 region. The major differences in U3 included variations in sets of small (14 to 19 base pair) direct repeats, altered location of the simian virus 40 core enhancer-like sequence, and occurrence of three segments of largely nonhomologous sequences. There was extensive homology between endogenous and exogenous FeLV LTRs in sequences beginning from the TATA box through the R region down to the 3' end of the U5 region. The DNA sequence downstream of the 5' LTR encompassing the primer-binding site, leader, and almost to the end of the p15gag coding region, a point up to which the sequencing was carried out, also revealed a high degree of conservation. However, the detection of frameshift and nonsense mutations in this region of a nearly full-length endogenous provirus sequence (CFE-6) predicted its defectiveness and correlated with the lack of infectivity of this DNA. The functional studies of the endogenous LTRs, based on linkage to the bacterial cat gene and transient expression in feline cell lines, indicated that although the basic characteristics for promotion and enhancement of transcription were retained in each LTR, there was a significant variation in the activity of the cat constructs. Reconstruction and deletion analyses with the CFE-6 5' LTR revealed the presence of strong transcription regulatory sequences in the 702-base-pair region immediately upstream of the 5' boundary of the endogenous LTR. These and related data suggest that in addition to the transcription-modulating elements occurring within the LTR, the cis-acting nucleotide sequences in the upstream cellular DNA may determine the overall efficiency of transcription of the defective endogenous FeLV provirus loci of the felid genome.


Assuntos
DNA Viral/genética , Vírus da Leucemia Felina/genética , Provírus/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Elementos Facilitadores Genéticos , Dados de Sequência Molecular , Plasmídeos , Regiões Promotoras Genéticas , Sequências Repetitivas de Ácido Nucleico , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica , Transfecção
18.
Appl Opt ; 21(6): 984-7, 1982 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20389788

RESUMO

A new method for tracing rays through graded-index media is presented. The method essentially consists of transforming the ray equation into a convenient form and solving the resulting equation using a standard numerical technique. A detailed comparison of this method with existing methods has also been made, and it is shown that for obtaining a desired accuracy this method requires much less computational effort.

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