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1.
Trop Med Int Health ; 19(4): 398-406, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24405627

RESUMO

OBJECTIVE: We tested whether soap presence in the home or a designated handwashing station was associated with diarrhoea and respiratory illness in Kenya. METHODS: In April 2009, we observed presence of a handwashing station and soap in households participating in a longitudinal health surveillance system in rural Kenya. Diarrhoea and acute respiratory illness (ARI) in children < 5 years old were identified using parent-reported syndromic surveillance collected January-April 2009. We used multivariate generalised linear regression to estimate differences in prevalence of illness between households with and without the presence of soap in the home and a handwashing station. RESULTS: Among 2547 children, prevalence of diarrhoea and ARI was 2.3 and 11.4 days per 100 child-days, respectively. Soap was observed in 97% of households. Children in households with soap had 1.3 fewer days of diarrhoea/100 child-days (95% CI -2.6, -0.1) than children in households without soap. ARI prevalence was not associated with presence of soap. A handwashing station was identified in 1.4% of households and was not associated with a difference in diarrhoea or ARI prevalence. CONCLUSIONS: Soap presence in the home was significantly associated with reduced diarrhoea, but not ARI, in children in rural western Kenya. Whereas most households had soap in the home, almost none had a designated handwashing station, which may prevent handwashing at key times of hand contamination.


Assuntos
Diarreia/prevenção & controle , Desinfecção das Mãos/instrumentação , Doenças Respiratórias/prevenção & controle , Sabões/provisão & distribuição , Abastecimento de Água/estatística & dados numéricos , Doença Aguda , Pré-Escolar , Diarreia/epidemiologia , Feminino , Desinfecção das Mãos/métodos , Humanos , Lactente , Recém-Nascido , Quênia/epidemiologia , Modelos Lineares , Masculino , Vigilância da População/métodos , Prevalência , Características de Residência , Doenças Respiratórias/epidemiologia , Saúde da População Rural
2.
Genet Mol Res ; 12(2): 1540-5, 2013 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-23765960

RESUMO

We previously demonstrated that alternaric acid, a host-specific toxin produced by the plant pathogenic fungus Alternaria solani, in the presence of Ca(2+) and Mg(2+), stimulated in vitro phosphorylation of His-tagged calcium-dependent protein kinase 2 from potato cultivar Rishiri (RiCDPK2). Herein, we report that Solanapyrone-A (SpA), a non-host-specific toxin produced by A. solani, inhibited the phosphorylation of RiCDPK2 in the presence of Ca(2+) and Mg(2+). However, SpA stimulated RiCDPK2 phosphorylation in the absence of these cations. Based on the current findings, we suggest that RiCDPK2 may mediate SpA-induced signaling independent of Ca(2+) and Mg(2+), leading to a compatible interaction between potato and A. solani.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Naftalenos/farmacologia , Proteínas Quinases/metabolismo , Pironas/farmacologia , Solanum tuberosum/efeitos dos fármacos , Solanum tuberosum/enzimologia , Cálcio/farmacologia , Solanum lycopersicum/efeitos dos fármacos , Magnésio/farmacologia , Fosforilação , Folhas de Planta/efeitos dos fármacos , Proteínas Recombinantes de Fusão/metabolismo
3.
Genet Mol Res ; 11(3): 2381-9, 2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22614453

RESUMO

Calcium-dependent protein kinases (CDPK) are an essential component of plant defense mechanisms against pathogens. We investigated the effect of alternaric acid, a host-specific toxin produced by the plant fungal pathogen Alternaria solani (Pleosporaceae), on a putative plasma membrane and cytosolic kinase RiCDPK2 of potato (Solanum tuberosum) and on hypersensitive cell death of host potato cells. Alternaric acid, in the presence of Ca²âº and Mg²âº, stimulated in vitro phosphorylation of His-tagged RiCDPK2, a Ca²âº-dependent protein kinase found in potato plants. We concluded that Ca²âº and Mg²âº play an important role in the interaction between alternaric acid and RiCDPK2. Based on our observations, alternaric acid regulates RiCDPK2 kinase during the infection process in an interaction between host and A. solani, leading to the inhibition of hypersensitive cell death in the host. We suggest that alternaric acid is a primary determinant by which A. solani stimulates CDPK activity in the host, suppressing hypersensitive cell death.


Assuntos
Ácidos/farmacologia , Ácidos Graxos Insaturados/farmacologia , Histidina/metabolismo , Oligopeptídeos/metabolismo , Proteínas Quinases/metabolismo , Pironas/farmacologia , Proteínas Recombinantes de Fusão/metabolismo , Solanum tuberosum/efeitos dos fármacos , Solanum tuberosum/enzimologia , Alternaria/química , Bioensaio , Cálcio/farmacologia , Ativação Enzimática/efeitos dos fármacos , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/microbiologia , Magnésio/farmacologia , Fosforilação/efeitos dos fármacos , Doenças das Plantas/microbiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/microbiologia , Solanum tuberosum/microbiologia
4.
Genet Mol Res ; 10(2): 889-901, 2011 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-21644206

RESUMO

Drought tolerance is one of the most important but complex traits of crops. We looked for quantitative trait loci (QTLs) that affect drought tolerance in maize. Two maize inbreds and their advanced lines were evaluated for drought-related traits. A genetic linkage map developed using RFLP markers was used to identify QTLs associated with drought-related traits. Twenty-two QTLs were detected, with a minimum of one and a maximum of nine for drought-related traits. A single-QTL was detected for sugar concentration accounting for about 52.2% of the phenotypic variation on chromosome 6. A single-QTL was also identified for each of the traits root density, root dry weight, total biomass, relative water content, and leaf abscisic acid content, on chromosomes 1 and 7, contributing to 24, 0.2, 0.4, 7, and 19% of the phenotypic variance, respectively. Three QTLs were identified for grain yield on chromosomes 1, 5, and 9, explaining 75% of the observed phenotypic variability, whereas four QTLs were detected for osmotic potential on chromosomes 1, 3, and 9, together accounting for 50% of the phenotypic variance. Nine QTLs were detected for leaf surface area on chromosomes 3 and 9, with various degrees of phenotypic variance, ranging from 25.8 to 42.2%. Four major clusters of QTLs were identified on chromosomes 1, 3, 7, and 9. A QTL for yield on chromosome 1 was found co-locating with the QTLs for root traits, total biomass, and osmotic potential in a region of about 15 cM. A cluster of QTLs for leaf surface area were coincident with a QTL for osmotic potential on chromosome 3. The QTLs for leaf area also clustered on chromosome 9, whereas QTLs for leaf abscisic acid content and relative water content coincided on chromosome 7, 10 cM apart. Co-location of QTLs for different traits indicates potential pleiotropism or tight linkage, which may be useful for indirect selection in maize improvement for drought tolerance.


Assuntos
Adaptação Fisiológica/genética , Secas , Locos de Características Quantitativas , Zea mays/fisiologia , Ligação Genética , Marcadores Genéticos , Variação Genética , Polimorfismo de Fragmento de Restrição , Zea mays/genética
5.
Proc Natl Acad Sci U S A ; 104(52): 20938-43, 2007 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-18087037

RESUMO

A major hurdle for current xenogenic-based and other approaches aimed at engineering kidney tissues is reproducing the complex three-dimensional structure of the kidney. Here, a stepwise, in vitro method of engineering rat kidney-like tissue capable of being implanted is described. Based on the fact that the stages of kidney development are separable into in vitro modules, an approach was devised that sequentially induces an epithelial tubule (the Wolffian duct) to undergo in vitro budding, followed by branching of a single isolated bud and its recombination with metanephric mesenchyme. Implantation of the recombined tissue results in apparent early vascularization. Thus, in principle, an unbranched epithelial tubular structure (potentially constructed from cultured cells) can be induced to form kidney tissue such that this in vitro engineered tissue is capable of being implanted in host rats and developing glomeruli with evidence of early vascularization. Optimization studies (of growth factor and matrix) indicate multiple suitable combinations and suggest both a most robust and a minimal system. A whole-genome microarray analysis suggested that recombined tissue recapitulated gene expression changes that occur in vivo during later stages of kidney development, and a functional assay demonstrated that the recombined tissue was capable of transport characteristic of the differentiating nephron. The approach includes several points where tissue can be propagated. The data also show how functional, 3D kidney tissue can assemble by means of interactions of independent modules separable in vitro, potentially facilitating systems-level analyses of kidney development.


Assuntos
Transplante de Rim/métodos , Rim/metabolismo , Engenharia Tecidual/métodos , Animais , Ânions , Transporte Biológico , Matriz Extracelular/metabolismo , Rim/anatomia & histologia , Rim/embriologia , Rim/patologia , Túbulos Renais/metabolismo , Mesoderma , Ratos , Biologia de Sistemas
6.
Genet Mol Res ; 9(1): 386-93, 2010 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-20309824

RESUMO

Tagetes, a genus of flowering marigolds in the family Asteraceae (Compositeae), is reported to be a medicinal plant with hypotensive, spasmolytic, anti-inflammatory, antimicrobial, and antifungal properties. Tagetes minuta characteristically contains high concentrations of essential oils, flavonoids, polyphenols, and polysaccharides that interfere with DNA, causing erroneous or no PCR products. We tested and modified various standard protocols in an effort to isolate high-quality DNA from different plant tissues of T. minuta. We used sun-dried, shade-dried and fresh-leaf tissues, as well as seeds for DNA analysis. The DNA obtained from seeds and fresh-leaf tissues with a modified cetyltrimethylammonium bromide buffer protocol was of good quality, with no colored pigments and contaminants. We were able to obtain good quality DNA from fresh leaf tissues without using liquid nitrogen. A relatively large amount of DNA was also extracted from the sun- and shade-dried tissues, but its quality was not as good as that from seeds. The DNA extracted from seeds and fresh leaves was successfully amplified by PCR using arbitrary RAPD primers. The same protocol will probably be useful for extracting high-molecular weight DNA from other plant materials containing large amounts of secondary metabolites and essential oils.


Assuntos
DNA de Plantas/isolamento & purificação , Folhas de Planta/genética , Reação em Cadeia da Polimerase/métodos , Sementes/genética , Tagetes/genética , Eletroforese em Gel de Ágar , Etídio/metabolismo , Coloração e Rotulagem
7.
Genet Mol Res ; 9(3): 1936-45, 2010 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-20882490

RESUMO

We compared DNA-based genetic diversity estimates with conventional estimates by investigating agronomically important traits in maize grown in the northwestern region of Pakistan. RAPD markers were used to characterize 10 commonly cultivated maize genotypes. The same material was tested for phenotypic variation of quantitative traits using replicated field trials. The genetic distances between pairs of genotypes using RAPD data were used to generate a similarity matrix and to construct a phenogram. Statistical analyses were carried out on the data obtained from field trials of all maize genotypes for days to 50% tasseling, days to 50% silking, plant height, ear height, grain yield, grain weight per cob, and ear length. Analysis of variance and single degree of freedom contrasts were performed on morphological data to examine the relationship between molecular-based clusters and agronomic traits. A molecular marker-based phenogram led to the grouping of all genotypes into four major clusters, some of which were distantly related. These clusters contained one to four genotypes. Analysis of variance showed significant variations among all genotypes for agronomic traits. The single degree of freedom contrasts between groups of genotypes indicated significant differences for most traits. Pair-wise comparisons between clusters were also significant. The two types of data correlated well, providing an opportunity for better choices for selection.


Assuntos
Marcadores Genéticos/genética , Zea mays/genética , Variação Genética/genética , Genótipo , Paquistão , Técnica de Amplificação ao Acaso de DNA Polimórfico
8.
Genet Mol Res ; 8(3): 783-93, 2009 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-19681030

RESUMO

Wheat is notorious for callus induction, which is a major hindrance in direct gene transfer and consequently for genetic improvement programs. In order to provide a successful platform for gene transformation, good callus quantity and quality is important. We investigated the variation in callus induction capabilities of Pakistani wheat cultivars and measured the reducing sugar content in the induced calluses. Ten elite wheat varieties, developed and cultivated in Pakistan were selected on the basis of agronomic and stress tolerance parameters. Significant differences were found between and among wheat cultivars for callus induction response, shoot length and callus quality. The callus induction responses of Punjab-81, Punjab-96 and Zarghoon-79 were found to be the best among the 10 varieties. The induced calluses were of two types, embryogenic (hard) and non-embryogenic (soft). The seeds gave good germination. The highest reducing sugar concentration was found in cultivar Sutlaj-86, which needs to be tested for stress resistance, a measure of its utility for genetic engineering programs. The relative callus induction rate and reducing sugar content of the wheat cultivars were found to be genotype-dependent.


Assuntos
Agricultura , Variação Genética , Técnicas de Cultura de Tecidos/métodos , Triticum/genética , Triticum/metabolismo , Carboidratos/análise , Meios de Cultura , Genótipo , Germinação , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/anatomia & histologia , Brotos de Planta/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento
9.
J Coll Physicians Surg Pak ; 19(5): 321-2, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19409169

RESUMO

The authors present a rare case of anti-Vel antibodies in a patient who underwent a shoulder replacement with a custom designed procedure which involved combination of autologous blood pre-deposit, pre-operative haemodilution and resurfacing arthroplasty.


Assuntos
Artrite/cirurgia , Artroplastia de Substituição/métodos , Antígenos de Grupos Sanguíneos/imunologia , Transfusão de Sangue/métodos , Isoanticorpos/sangue , Articulação do Ombro , Idoso , Artrite/sangue , Artrite/imunologia , Hemodiluição , Humanos
10.
J Appl Microbiol ; 104(6): 1815-23, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18248366

RESUMO

AIMS: To develop a rapid and sensitive method for detecting Brucella spp. METHODS AND RESULTS: Two sets of six Brucella-specific primers for loop-mediated isothermal amplification (LAMP) were designed from the sequence of the Brucella abortus BCSP31 gene. The specificity and sensitivity were examined for six Brucella species (22 strains) and 18 non-Brucella species (28 strains). The LAMP assay was specific to Brucella spp. in 35 min at 63 degrees C and sensitive (detected 10 fg of genomic DNA). The assay was also applied for the detection of Brucella DNA in contaminated milk and infected mouse organs. CONCLUSIONS: We developed a sensitive and specific LAMP assay for Brucella spp., with the test appearing to be useful for the detection of the pathogen from clinical and food samples. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of the development of LAMP for the detection of Brucella spp. As the LAMP assay can be performed at a constant temperature and its reactivity is directly observed with the naked eye without electrophoresis, our assay should be useful for the diagnosis of brucellosis as well as the detection of the bacteria in environmental or food samples.


Assuntos
Brucella/genética , Brucelose/diagnóstico , DNA Bacteriano/análise , Animais , Sequência de Bases , Brucella/isolamento & purificação , Primers do DNA/genética , DNA Bacteriano/genética , Engenharia Genética , Camundongos , Leite/microbiologia , Dados de Sequência Molecular , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
11.
Genet Mol Res ; 6(4): 1123-30, 2007 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-18273806

RESUMO

Ephedra, also known as "ma huang", is a dioecious, drought- and frost-resistant, perennial, evergreen shrub with compelling medicinal value. The genus is represented by 42 species around the world, 9 of which were provisionally reported from Pakistan. Species of the genus have a controversial taxonomy due to their overlapping morphological features. Conventional tools alone are not sufficient for characterizing the species. The objective of present study was to assess the genetic variability present in different biotypes of Ephedra growing in Pakistan using molecular markers. A total of six genotypes collected from diverse geographic zones of Pakistan were used. The DNA of all genotypes was amplified using nine randomly amplified polymorphic DNA (RAPD) primers to study genetic variability at the molecular level. The dissimilarity coefficient matrix based on the data of 9 RAPD primers was used to construct a dendrogram which was then used to group the genotypes in clusters. Based on the dendrogram and dissimilarity coefficient matrix, the RAPD markers used here revealed a moderate to high level of genetic polymorphism (6 to 49%) among the genotypes. It was found that the collection of genotype accessions from Swat Valley in northwestern Pakistan was most distantly related to the other five collections. More molecular markers including functional genes and ribosomal spacer regions are suggested to find a better estimate of the genetic diversity present in Ephedra growing in Pakistan. The information provided here is useful for identifying valuable Ephedra variants which will be used for medicinal purposes and earning foreign currency.


Assuntos
Ephedra/genética , Sequência de Bases , Primers do DNA/genética , DNA de Plantas/genética , Ecossistema , Variação Genética , Genótipo , Paquistão , Plantas Medicinais/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico
12.
J Parasit Dis ; 41(1): 1-8, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28316380

RESUMO

Domestic animals are susceptible to a large number of parasitic diseases, which lead to severe economic losses to livestock industry. So, it is necessary to control parasitic infections in these animals. Control of these helminths is undertaken mostly by anthelmintics, but because of their widespread use there is development of resistance across the globe. However, total dependence on a single method of control has proved to be non-sustainable and cost ineffective in the long term. A combination of treatment and management is necessary to control parasitism so that it will not cause further economic losses to producer as well as to livestock industry. To become practically and ecologically sustainable, parasitic control schemes need to be based on integrated parasite management.

13.
Clin Oncol (R Coll Radiol) ; 29(2): 135-140, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27955997

RESUMO

Closing the gap in cancer care within low- and middle-income countries and in indigenous and geographically isolated populations in high-income countries requires investment and innovation. This is particularly true for radiotherapy, for which the global disparity is one of the largest in healthcare today. New models and paradigms and non-traditional collaborations have been proposed to improve global equity in cancer control. We describe recent initiatives from within the radiation oncology community to increase access to treatment, build the low- and middle-income countries' radiation oncology workforce, mobilise more professionals from within high-income countries and raise awareness of the global need for equitable cancer care.


Assuntos
Países em Desenvolvimento , Disparidades em Assistência à Saúde , Neoplasias , Radioterapia (Especialidade) , Saúde Global , Necessidades e Demandas de Serviços de Saúde , Humanos , Renda , Neoplasias/radioterapia
14.
Genetics ; 168(2): 595-608, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15514038

RESUMO

A total of 37 original cDNA libraries and 9 derivative libraries enriched for rare sequences were produced from Chinese Spring wheat (Triticum aestivum L.), five other hexaploid wheat genotypes (Cheyenne, Brevor, TAM W101, BH1146, Butte 86), tetraploid durum wheat (T. turgidum L.), diploid wheat (T. monococcum L.), and two other diploid members of the grass tribe Triticeae (Aegilops speltoides Tausch and Secale cereale L.). The emphasis in the choice of plant materials for library construction was reproductive development subjected to environmental factors that ultimately affect grain quality and yield, but roots and other tissues were also included. Partial cDNA expressed sequence tags (ESTs) were examined by various measures to assess the quality of these libraries. All ESTs were processed to remove cloning system sequences and contaminants and then assembled using CAP3. Following these processing steps, this assembly yielded 101,107 sequences derived from 89,043 clones, which defined 16,740 contigs and 33,213 singletons, a total of 49,953 "unigenes." Analysis of the distribution of these unigenes among the libraries led to the conclusion that the enrichment methods were effective in reducing the most abundant unigenes and to the observation that the most diverse libraries were from tissues exposed to environmental stresses including heat, drought, salinity, or low temperature.


Assuntos
Etiquetas de Sequências Expressas/química , Biblioteca Gênica , Triticum/genética , Vetores Genéticos , Análise de Sequência de DNA , Técnica de Subtração
15.
AIDS ; 10(11): 1239-47, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8883586

RESUMO

OBJECTIVE: To compare the effects of zidovudine (ZDV) on clonal maturation of hematopoietic progenitors obtained from the bone marrow of women of child-bearing age with its effects on progenitors obtained from the marrow, liver and blood of fetuses. We also sought to determine whether the adverse effects of ZDV on fetal hematopoiesis resulted exclusively from an action on progenitors, or also involved the inhibition of the production of hematopoietic growth factors. PARTICIPANTS: Hematopoietic progenitors were obtained from bone-marrow aspirates of seven women of child-bearing age, from the bone marrow and liver of seven mid-trimester abortuses, and from the umbilical cord blood of seven term infants. METHODS: We added increasing concentrations of ZDV to clonal assays of hematopoietic progenitors, after which we assayed clonal maturation of progenitors, and counted the number of erythrocytes per erythroid clone and the number of neutrophils per granulocytic clone. Light-density cell fractions and enriched CD34+ progenitor fractions were studied. In other studies we determined the effect of increasing concentrations of ZDV on production of granulocyte colony-stimulating factor (G-CSF) protein [enzyme-linked immunosorbent assay (ELISA)] and mRNA by fetal and maternal monocytes, and on production of erythropoietin protein (ELISA) and mRNA by Hep3B cells. RESULTS: Mature erythroid progenitors were the most sensitive to the adverse effects of ZDV on clonal maturation, and multipotent progenitors were the most resistant. Erythroid progenitors from all fetal and neonatal sources were more sensitive to the effect of ZDV than those from the bone marrow of adult women. The inhibitory effects were explained by an action on CD34+ cells; no effect was observed on production of G-CSF or erythropoietin. CONCLUSIONS: We speculate that the low hematocrits of neonates delivered after antenatal ZDV treatment are due to reduced clonal maturation of erythroid progenitors, and that fetal erythroid progenitors are inhibited to a greater extent than maternal progenitors.


Assuntos
Feto/citologia , Hematopoese/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Mães , Zidovudina/farmacologia , Adulto , Eritropoetina/biossíntese , Feminino , Fator Estimulador de Colônias de Granulócitos/biossíntese , Células-Tronco Hematopoéticas/metabolismo , Humanos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo
16.
Endocrinology ; 136(8): 3611-8, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7628400

RESUMO

MRL-lpr/lpr mice manifest a systemic lupus-like autoimmune disease. As part of this syndrome, the mice spontaneously develop autoimmune thyroiditis, which is morphologically and biochemically similar to human autoimmune thyroiditis. In this study we investigated whether thyroid tissue obtained from sites of chronic inflammation had altered gap junctional communication. Fresh tissue sections revealed that thyroid from the nondiseased mice (MRL-(+)/+) had connexins (Cx) localized to the plasma membrane at points of thyroid cell-cell contact. In contrast, the Cx in diseased mouse (MRL-lpr/lpr) thyroid tissue were not localized to the plasma membrane, and the fluorescent intensity was reduced for Cx43 and Cx26. Northern analysis confirmed that murine thyroid tissue expressed messenger RNA for these Cx. However, the diseased tissue expressed lower levels of Cx32 and Cx26 messenger RNA. The infiltrating cells and their biologically active products present in the diseased thyroid tissue may mediate the reduced Cx expression and aberrant gap junctional assembly. We established primary thyrocyte cultures to determine whether these differences persisted when the inflammatory factors were removed. The nondiseased thyroid cells were communication competent, with fluorescent dye transfer proceeding from the injected cell to primary contacts (95%) and to second and third order neighboring cells in 75% of the trials. Thyroid cells from the diseased mice were communication incompetent, in that 80% of microinjections failed to result in dye transfer to cells in direct contact. Immunocytochemistry indicated that the functional coupling in the normal mouse thyroid cells was associated with Cx43 located in the plasma membrane as assembled gap junctional plaques. The communication-deficient diseased thyroid cells had internalized Cx43 predominantly localized to perinuclear regions of the cells. Collectively, these data document altered Cx-protein distribution in the autoimmune diseased thyroid. The diseased thyroid tissue was devoid of plasma membrane identifiable gap junctions and deficient in intercellular communication. Culturing removed the inflammatory mediators; however, the disease cells retained their communication incompetence. These results suggest that if this deficiency was initiated by components of the inflammation process, then protracted changes must have occurred so that the continued presence of these factors was no longer required to sustain this difference.


Assuntos
Comunicação Celular , Tireoidite Autoimune/patologia , Animais , Células Cultivadas , Conexina 26 , Conexinas/genética , Conexinas/metabolismo , Espaço Extracelular/metabolismo , Feminino , Corantes Fluorescentes , Imuno-Histoquímica , Isoquinolinas , Camundongos , Camundongos Endogâmicos , RNA Mensageiro/metabolismo , Valores de Referência , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Tireoidite Autoimune/metabolismo
17.
J Mol Endocrinol ; 27(2): 145-63, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11564600

RESUMO

In this study we examine changes in the cellular properties of FRTL-5 cells as a function of passage number, with particular emphasis on gap junction expression, karyotype, morphology, growth rate and thyroxine (T(4)) release. Early passage FRTL-5 follicular cells transfer dye through gap junctions from injected cell(s) to third-order neighboring cells and beyond within their respective follicles and have immuno-detectable connexin32 (Cx32) type gap junctional plaques in their lateral contacting plasma membranes. By contrast, FRTL-5 cells established as monolayers, or as follicles from cultures passed more than 15 times, did not transfer microinjected Lucifer Yellow dye to contiguous neighboring cells and did not express any immuno-detectable rat thyroid specific connexins (Cx43, Cx32 or Cx26). Western blots confirmed that total, membrane and cytosolic Cx32 protein was present only in early pass follicular cultures. To better understand the passage-dependent loss of Cx32 expression, RT-PCR primers were made to the most unique sequences of the rat Cx32 molecule, the cytoplasmic and carboxyl-terminal regions. These primers were used to screen FRTL-5 RNA from cultures of various passage numbers. The results revealed that later passage cultures had a single base deletion in the middle of the Cx32 cytoplasmic loop region at nucleotide position 378. This base deletion was in the middle position of the codon for amino acid 116, which is normally a CAC (histidine) but read with the frame shift was a CCC (proline). The four amino acids that followed this deletion were also altered with the fourth one becoming UAA, the ochre translation stop codon. This premature stopping of translation resulted in a truncation of 60% of the protein, which included the remaining cytoplasmic loop, third and fourth transmembrane regions and the carboxyl-terminus. The later passage cultures did not produce a carboxyl-terminal RT-PCR product, indicating that the mRNA was also truncated. These regions of the Cx32 molecule contain the sequences and epitopes to which probes and antibodies are directed, and as such alterations of these regions with repeated passage explains reports by others that FRTL-5 cells do not express Cx32, and implies that cultures used for these assessments were passed more than 15 times. To determine if genetic or epigenetic abnormalities existed in FRTL-5 cells we performed chromosome spreads from various passage cultures. FRTL-5 cells have been reported to be diploid and more recently non-diploid; however, we found them to be fully tetraploid. This tetraploidy appears to be unstable in that later passes are tetraploid plus two or three extra chromosomes. There were no obvious translocations, breaks or large-scale interstitial deletions of any chromosomes in the FRTL-5 cultures tested. As FRTL-5 cells were repeatedly passed their morphology changed. Monolayer areas spread from beneath the follicles, and the follicles became flattened in appearance. These physical changes were coincident with dramatically increased growth rates. Early cultures (passed 3-12 times) divided on average every 49+/-1 h, whereas later passes (passes 20-25) divided every 28+/-3 h. To correlate these changes with a measure of thyroid function we assayed T(4) output. Early passage follicular cultures incubated for 6 h with sodium iodide, released on average 5.27+/- 0.33 ng/ml of T(4)/100 follicles. Later passes, or early passes treated with heptanol to down-regulate Cx32, released an average of 3.84+/-0.50 ng/ml of T(4)/100 follicles. There was a 27% difference in T(4) release between early follicular cultures, that were coupled by Cx32, and late or down-regulated early follicular cultures, that were uncoupled (P<0.0001). Collectively, the physical changes documented in this study were coincident with the loss of functional Cx32. This implies a relationship between the loss of intercellular communication and changes in morphogenic appearance, growth rate and reduced thyroid function and supports the previously postulated, tumor-suppressor role for Cx32. FRTL-5 cultures from low passage numbers are an excellent model of primary thyroid cells. However, many reports in the literature ascribe features to FRTL-5 cells that are mutually inconsistent. These differences may be resolved in the future by addressing the passage number and the conditional differences of the cultures being studied.


Assuntos
Conexinas/genética , Mutação , Sequência de Aminoácidos , Animais , Sequência de Bases , Comunicação Celular , Técnicas de Cultura de Células , Divisão Celular , Linhagem Celular , Conexinas/metabolismo , DNA/genética , Junções Comunicantes/fisiologia , Expressão Gênica , Cariotipagem , Dados de Sequência Molecular , Mutação Puntual , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Deleção de Sequência , Glândula Tireoide/citologia , Glândula Tireoide/metabolismo , Tiroxina/metabolismo , Proteína beta-1 de Junções Comunicantes
18.
Br J Pharmacol ; 132(4): 889-98, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11181430

RESUMO

1. The pharmacology of the slow afterhyperpolarization (sAHP) was studied in cultured rat hippocampal pyramidal neurones. 2. Clotrimazole, its in vivo metabolite, 2-chlorophenyl-bisphenyl-methanol (CBM) and the novel analogues, UCL 1880 and UCL 2027, inhibited the sI(AHP) with similar IC50s (1-2 microM). 3. Clotrimazole and CBM also inhibited the high voltage-activated (HVA) Ca2+ current in pyramidal neurones with IC50s of 4.7 microM and 2.2 microM respectively. UCL 1880 was a less effective Ca2+ channel blocker, reducing the HVA Ca2+ current by 50% at 10 microM. At concentrations up to 10 microM, UCL 2027 had no effect on the Ca2+ current, indicating that its effects on the sI(AHP) were independent of Ca2+ channel block. 4. Clotrimazole also inhibited both the outward holding current (IC50=2.8 microM) present at a potential of -50 mV and the apamin-sensitive medium AHP (mAHP; IC50 approximately amp;10 microM). The other clotrimazole analogues tested had smaller effects on these two currents. The present work also shows that 100 nM UCL 1848, an inhibitor of apamin-sensitive conductances, abolishes the mAHP. 5. Currents were recorded from HEK293 cells transfected with hSK1 and rSK2. The SK currents were very sensitive to inhibition by UCL 1848 but were not significantly reduced by the sI(AHP) inhibitor, UCL 2027 (10 microM). 10 microM UCL 1880 reduced the hSK1 current by 40%. 6. UCL 2027 appears to be the first relatively selective blocker of the sAHP to be described. Furthermore, the ability of UCL 2027 to block the sAHP with minimal effect on SK1 channel activity questions the role of this channel in the sAHP.


Assuntos
Clotrimazol/farmacologia , Canais de Potássio/fisiologia , Células Piramidais/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Animais , Canais de Cálcio/efeitos dos fármacos , Células Cultivadas , Canais de Potássio/efeitos dos fármacos , Células Piramidais/fisiologia , Ratos , Ratos Sprague-Dawley
19.
Clin Chim Acta ; 94(1): 41-9, 1979 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-88284

RESUMO

A rapid enzyme linked immunoassay for pregnancy specific beta 1-glycoprotein is described. The method is sensitive and precise (within batch C.V. = 6.5-7.4%) and should be suitable for the biochemical monitoring of pregnancy and the investigation of patients suffering from various malignancies.


Assuntos
beta-Globulinas/análise , Gravidez , Feminino , Humanos , Soros Imunes , Técnicas Imunoenzimáticas , Fatores de Tempo
20.
Toxicol Lett ; 64-65 Spec No: 493-501, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1281938

RESUMO

White rot fungi have been shown to mineralize a wide variety of environmental pollutants. These fungi secrete a number of enzymes that are involved in its unique ability to degrade lignin, the structural component of woody plants. Lignin is a very complex heteropolymer that can only be degraded by white rot fungi. Degradation is complete without energy value to the fungus. The evolution of this ability has apparently given the organism the ability to degrade structurally diverse and normally very recalcitrant environmental pollutants such as DDT, PCB, benzo(a)pyrene, TNT, etc. Some of the major enzymes that are secreted by the fungi are peroxidases with unique properties. In addition to their ability to catalyze a wide variety of oxidations, they can also catalyze indirect oxidations and reductions. The fungi synthesize and secrete hydrogen peroxide to activate the peroxidases, veratryl alcohol to serve as a free radical intermediate for indirect oxidations, and electron donors, such as oxalate, which with veratryl alcohol catalyze reductions. Reductions are often required for subsequent oxidation of chemicals by the peroxidases. The enzymes can also reduce molecular oxygen.


Assuntos
Basidiomycota/metabolismo , Poluentes Ambientais/metabolismo , Peroxidases/metabolismo , Biodegradação Ambiental , Tetracloreto de Carbono/metabolismo , DDT/metabolismo , Hexaclorocicloexano/metabolismo , Oxirredução
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