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1.
Sci Rep ; 9(1): 9440, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31263114

RESUMO

Citrus greening or huanglongbing (HLB) is the main threat to the European citrus industry since one of its vectors, the African citrus psyllid, Trioza erytreae, has recently become established in mainland Europe. In this context, classical biological control programmes should be implemented to reduce the spread of the psyllid. The aims of this study were to: i) disentangle the parasitoid complex of T. erytreae combining morphological and molecular characterization; and ii) to study the biology of its main parasitoids in its area of origin in South Africa for their future importation into Europe. The main citrus producing areas of South Africa were surveyed during 2017. In contrast to previous studies, the parasitoid complex of T. erytreae included three species of primary parasitoids: Tamarixia dryi, Psyllaephagus pulvinatus and another parasitoid of the genus Tamarixia. Molecular analysis showed that it is a new species closely related to T. dryi. Tamarixia dryi was the most abundant parasitoid but its relative abundance varied among sampling sites. The sex ratio (males/females) of T. dryi and Tamarixia sp. decreased with T. erytreae size and became female biased when psyllid nymphs were larger than 0.6 and 1.2 mm2, respectively. These parasitoids were attacked by three species of hyperparasitoids, Aphidencyrtus cassatus, Marietta javensis and a species of the genus Aphanogmus. Aphidencyrtus cassatus, the most abundant hyperparasitoid, tended to emerge from large nymphs, and adult females lived as long as those of T. dryi. The implications of these results are discussed within the framework of the introduction of T. dryi into Europe.


Assuntos
Citrus/parasitologia , Hemípteros/fisiologia , Animais , Código de Barras de DNA Taxonômico , Europa (Continente) , Feminino , Hemípteros/classificação , Hemípteros/crescimento & desenvolvimento , Hemípteros/parasitologia , Himenópteros/classificação , Himenópteros/fisiologia , Masculino , Ninfa/parasitologia , Ninfa/fisiologia , Controle Biológico de Vetores , Filogenia , Estações do Ano , África do Sul
2.
Transl Psychiatry ; 5: e655, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26460479

RESUMO

Cadherin-13 (CDH13), a unique glycosylphosphatidylinositol-anchored member of the cadherin family of cell adhesion molecules, has been identified as a risk gene for attention-deficit/hyperactivity disorder (ADHD) and various comorbid neurodevelopmental and psychiatric conditions, including depression, substance abuse, autism spectrum disorder and violent behavior, while the mechanism whereby CDH13 dysfunction influences pathogenesis of neuropsychiatric disorders remains elusive. Here we explored the potential role of CDH13 in the inhibitory modulation of brain activity by investigating synaptic function of GABAergic interneurons. Cellular and subcellular distribution of CDH13 was analyzed in the murine hippocampus and a mouse model with a targeted inactivation of Cdh13 was generated to evaluate how CDH13 modulates synaptic activity of hippocampal interneurons and behavioral domains related to psychopathologic (endo)phenotypes. We show that CDH13 expression in the cornu ammonis (CA) region of the hippocampus is confined to distinct classes of interneurons. Specifically, CDH13 is expressed by numerous parvalbumin and somatostatin-expressing interneurons located in the stratum oriens, where it localizes to both the soma and the presynaptic compartment. Cdh13(-/-) mice show an increase in basal inhibitory, but not excitatory, synaptic transmission in CA1 pyramidal neurons. Associated with these alterations in hippocampal function, Cdh13(-/-) mice display deficits in learning and memory. Taken together, our results indicate that CDH13 is a negative regulator of inhibitory synapses in the hippocampus, and provide insights into how CDH13 dysfunction may contribute to the excitatory/inhibitory imbalance observed in neurodevelopmental disorders, such as ADHD and autism.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Hipocampo , Ácido gama-Aminobutírico/metabolismo , Animais , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Caderinas/genética , Modelos Animais de Doenças , Genes Supressores de Tumor , Hipocampo/metabolismo , Hipocampo/patologia , Interneurônios/fisiologia , Aprendizagem/fisiologia , Memória/fisiologia , Camundongos , Psicopatologia , Transmissão Sináptica/genética
3.
Eur Neuropsychopharmacol ; 24(1): 65-85, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24220657

RESUMO

NO is a pleiotropic signaling molecule and has an important role in cognition and emotion. In the brain, NO is produced by neuronal nitric oxide synthase (NOS-I, encoded by NOS1) coupled to the NMDA receptor via PDZ interactions; this protein-protein interaction is disrupted upon binding of NOS1 adapter protein (encoded by NOS1AP) to NOS-I. As both NOS1 and NOS1AP were associated with schizophrenia, we here investigated these genes in greater detail by genotyping new samples and conducting a meta-analysis of our own and published data. In doing so, we confirmed association of both genes with schizophrenia and found evidence for their interaction in increasing risk towards disease. Our strongest finding was the NOS1 promoter SNP rs41279104, yielding an odds ratio of 1.29 in the meta-analysis. As findings from heterologous cell systems have suggested that the risk allele decreases gene expression, we studied the effect of the variant on NOS1 expression in human post-mortem brain samples and found that the risk allele significantly decreases expression of NOS1 in the prefrontal cortex. Bioinformatic analyses suggest that this might be due the replacement of six transcription factor binding sites by two new binding sites as a consequence of proxy SNPs. Taken together, our data argue that genetic variance in NOS1 resulting in lower prefrontal brain expression of this gene contributes to schizophrenia liability, and that NOS1 interacts with NOS1AP in doing so. The NOS1-NOS1AP PDZ interface may thus well constitute a novel target for small molecules in at least some forms of schizophrenia.


Assuntos
Ácido Glutâmico/metabolismo , Óxido Nítrico/genética , Córtex Pré-Frontal/patologia , Esquizofrenia/patologia , Transdução de Sinais/genética , Sinapses/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Biologia Computacional , Predisposição Genética para Doença , Humanos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo I/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Esquizofrenia/genética
5.
Medicina (B Aires) ; 61(3): 322-4, 2001.
Artigo em Espanhol | MEDLINE | ID: mdl-11474882

RESUMO

Adenocarcinomas (AC) account for more than 90% of the prostatic malignant neoplasias; a neuroendocrine differentiation (NE) component is to be considered in cases of atypical evolution for its diagnostic and therapeutic relevance. The (NE) originates by proliferation of the NE cells of the acinar epithelium and may develop into two different histologic patterns, a "Carcinoid" type and a "Small Cell" type. We report a patient with a prostatic AC diagnosed 5 years before his death with worsening of the disease together with a return of the prostatic specific antigen (PSA) to normal values and the presence of hepatic metastases of a tumor (NE) of the small cell type. The autopsy confirmed the presence of a prostatic tumor with areas of (AC) type and (NE) small cell type and multiple hepatic metastases (NE).


Assuntos
Adenocarcinoma/patologia , Carcinoma de Células Pequenas/patologia , Sistemas Neurossecretores/patologia , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia , Idoso , Transformação Celular Neoplásica , Evolução Fatal , Humanos , Masculino , Tumores Neuroendócrinos/patologia
6.
Medicina [B Aires] ; 61(3): 322-4, 2001.
Artigo em Espanhol | BINACIS | ID: bin-39489

RESUMO

Adenocarcinomas (AC) account for more than 90


of the prostatic malignant neoplasias; a neuroendocrine differentiation (NE) component is to be considered in cases of atypical evolution for its diagnostic and therapeutic relevance. The (NE) originates by proliferation of the NE cells of the acinar epithelium and may develop into two different histologic patterns, a [quot ]Carcinoid[quot ] type and a [quot ]Small Cell[quot ] type. We report a patient with a prostatic AC diagnosed 5 years before his death with worsening of the disease together with a return of the prostatic specific antigen (PSA) to normal values and the presence of hepatic metastases of a tumor (NE) of the small cell type. The autopsy confirmed the presence of a prostatic tumor with areas of (AC) type and (NE) small cell type and multiple hepatic metastases (NE).

7.
Plant Mol Biol ; 36(5): 639-48, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9526496

RESUMO

Tomato and potato leucine aminopeptidase (LAP) mRNAs are induced in response to mechanical wounding and the wound signal molecules, ABA and jasmonic acid. Here, we report the isolation of two LAP genes, LAP17.1A and LAP17.2, from tomato. Functional analysis in transgenic tomato and potato plants show that fusions of the corresponding 5' non-coding regions to the gusA gene are constitutively expressed in flowers and induced in leaves upon wounding or by treatment with methyl jasmonate (MeJA). Comparison of the 5' non-coding regions of the two genes revealed a region from -317 to -3 relative to the ATG, which is strongly conserved in both promoters. This 0.3 kb proximal promoter fragment is sufficient to direct flower-specific and MeJA-inducible GUS activity in transgenic potato plants, and thus contains a MeJA-responsive element that mediates induction by MeJA. Dimeric TGACG motifs or G-box elements similar to those found in other MeJA-inducible genes are not observed in this region, which suggests that a different DNA sequence is involved in MeJA induction of the LAP genes.


Assuntos
Genes de Plantas , Leucil Aminopeptidase/genética , Regiões Promotoras Genéticas , Solanum lycopersicum/enzimologia , Solanum lycopersicum/genética , Acetatos/farmacologia , Sequência de Bases , Ciclopentanos/farmacologia , Primers do DNA/genética , DNA de Plantas/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Dados de Sequência Molecular , Oxilipinas , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/enzimologia , Folhas de Planta/genética , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA de Plantas/biossíntese , RNA de Plantas/genética , Deleção de Sequência , Homologia de Sequência do Ácido Nucleico , Solanum tuberosum/enzimologia , Solanum tuberosum/genética
8.
Chest ; 104(5): 1477-81, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8222810

RESUMO

Lung cancer in young patients is increasing in frequency, as documented by data from the United States, Canada, Japan, and European countries. However, to date and to our knowledge, there have not been any reports from Latin America on this topic. The published reports show that lung cancer in young patients is associated with smoking habit and family history of lung cancer. Its clinical course seems to be more aggressive than in older patients and the histologic type is less often squamous type. We describe 48 patients, aged 40 years or younger, who were diagnosed as having lung cancer in the Instituto Nacional de Cancerología from 1980 to 1990. The patients were equally divided between men and women. Smoking was documented for only 46 percent of the cases. The histologic type most frequently diagnosed was adenocarcinoma (N = 26) followed by squamous cell carcinoma (N = 12). Almost all the cases (46 cases) were staged IV according to the TNM classification. A group of 33 patients older than 40 years (56 to 82 years) were used for comparison. The differences in sex ratio that were higher for men in the elder (m/f, 2.7:1) were family history for cancer in six patients elder; positive smoking habit in all the aged patients (100 percent) compared with only 43.7 percent in the younger group; histologic type (26 adenocarcinomas and 4 squamous in the younger compared with 14 and 12, respectively, in the elder).


Assuntos
Carcinoma Broncogênico/epidemiologia , Neoplasias Pulmonares/epidemiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma Broncogênico/mortalidade , Carcinoma Broncogênico/patologia , Feminino , Humanos , Incidência , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fatores de Risco , Fatores Sexuais , Fumar/epidemiologia , Fatores Socioeconômicos , População Urbana/estatística & dados numéricos
9.
Zentralbl Hyg Umweltmed ; 193(2): 114-22, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1388613

RESUMO

Seventy-four strains of Aeromonas hydrophila isolated from water and sediments of the River Porma (León, N.W. Spain) were characterized biochemically and biologically. Fifty-seven strains (77.02%) were virulent for rainbow trout (Salmo gairdneri) by intramuscular challenge but showed differing degree of pathogenicity which could not be associated with the source. A lack of correlation between caseinase, haemolytic and cytotoxic activities of the strains and their isolation source was also observed. Only two surface characters, acriflavine 0.2% agglutination and non-agglutinating SP-/PAB-phenotypes, were significantly associated with water and sediment strains, respectively.


Assuntos
Aeromonas hydrophila/patogenicidade , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Truta , Microbiologia da Água , Aeromonas hydrophila/isolamento & purificação , Aglutinação , Animais , Água Doce , Infecções por Bactérias Gram-Negativas/microbiologia , Hemaglutinação , Estações do Ano , Virulência
10.
Appl Environ Microbiol ; 58(3): 1031-4, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16348662

RESUMO

A genomic library of Aeromonas hydrophila F9 was constructed by using pBR322 as a vector. From that, two DNA fragments (5.8 and 11.6 kb) were isolated containing genetic information to complement trpA and trpB defects (5.8-kb fragment) and to complement trpA, trpB, trpC, trpD, and trpE defects (11.6-kb fragment) in Escherichia coli mutants. Evidence of the existence of a secondary promoter is given.

11.
FEMS Microbiol Lett ; 65(1): 1-7, 1991 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-1874394

RESUMO

Aeromonas virulence is thought to depend on multigenic functions. The gene for an extracellular protease from Aeromonas hydrophila SO2/2 was cloned in Escherichia coli C600-1 by using pIJ860, bifunctional plasmid, as a vector. The gene encodes for a temperature-labile serine protease (P2) with a molecular mass of approx. 68 kDa which is highly inhibited by PMSF. The gene was expressed in Streptomyces lividans 1326 by transforming protoplasts with the original clone pPA2. We were also able to transfer and express the prt P2 gene in Pseudomonas putida by mating experiments. The protein P2 was secreted into the periplasms of both P. putida and E. coli C600-1 being identical in properties to one of the proteases secreted into the culture supernatant by A. hydrophila SO2/2.


Assuntos
Aeromonas/genética , Clonagem Molecular , Genes Bacterianos , Serina Endopeptidases/genética , Aeromonas/enzimologia , Serina Endopeptidases/análise , Temperatura
12.
G E N ; 44(4): 393-6, 1990.
Artigo em Espanhol | MEDLINE | ID: mdl-2152283

RESUMO

Ascariasis is one of the most frequent intestinal parasitosis of man, specially in tropical regions where it affects mostly children. The adult worm can migrate through the ampulla of vater and penetrate the bile ducts producing different degrees of obstruction and infection. Ultrasonography is a rapid and simple non invasive procedure very effective for the visualization of the worm in the biliary tree. We present the clinical and ultrasonographic characteristic of biliary ascariasis in five children diagnosed by ultrasonography in our institution during the last nine years.


Assuntos
Ascaríase/diagnóstico por imagem , Ascaris lumbricoides , Doenças Biliares/diagnóstico por imagem , Animais , Doenças Biliares/parasitologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Ultrassonografia
13.
J Bacteriol ; 172(7): 3905-8, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2193924

RESUMO

A structural gene which codes for an extracellular protease in Aeromonas hydrophilia SO2/2 and D13 was cloned in Escherichia coli C600-1 by using pBR322 as a vector. The gene codes for a temperature-stable protease with a molecular mass of approximately 38,000 daltons. The protein was secreted to the periplasm of E. coli C600-1 and purified by osmotic shock. Cloned protease (P3) was identical in molecular mass and properties to the one purified from A. hydrophila SO2/2 culture supernatant as an extracellular product.


Assuntos
Aeromonas/genética , Genes Bacterianos , Peptídeo Hidrolases/genética , Aeromonas/enzimologia , Cromossomos Bacterianos , Clonagem Molecular/métodos , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Escherichia coli/genética , Cinética , Hibridização de Ácido Nucleico , Peptídeo Hidrolases/isolamento & purificação , Peptídeo Hidrolases/metabolismo , Plasmídeos , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Mapeamento por Restrição
14.
J Clin Microbiol ; 28(2): 350-5, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2312678

RESUMO

Ninety-seven motile Aeromonas strains were isolated over a period of a year from samples of water and sediment collected at different sites along a river. Strains were regularly recovered from all samples, regardless of the source of isolation or seasonal conditions. Isolates were biochemically characterized by the API 20NE system (Analytab Products, Plainview, N.Y.) and classified as Aeromonas hydrophila (74 strains), Aeromonas sobria (11 strains), and Aeromonas caviae (12 strains). Despite the high level of homogeneity observed in their biochemical patterns, they displayed different degrees of virulence for fish; 72.02% of A. hydrophila isolates and 63% of A. sobria isolates were virulent for fish by intramuscular challenge, but lower frequencies of virulence were observed when intraperitoneal injections were used. All A. caviae strains proved to be avirulent. Caseinases, hemolysins, and Vero cytotoxins were produced by 100, 91, and 94.59%, respectively, of A. hydrophila strains and with lower frequencies and lower caseinase activities by A. sobria isolates. No correlation was found between these activities and the degree of virulence of the strains for fish. Most hydrophobic strains seem to be concentrated in A. caviae, A. sobria, and avirulent A. hydrophila groups. Known virulence markers commonly associated with virulent strains (acriflavine negative and self-pelleting negative and precipitation after boiling positive phenotypes) had a low representation in the total of strains studied and were not associated with virulence.


Assuntos
Aeromonas/patogenicidade , Salmonidae/microbiologia , Truta/microbiologia , Aeromonas/isolamento & purificação , Aeromonas/fisiologia , Animais , Infecções Bacterianas/etiologia , Doenças dos Peixes/etiologia , Fenótipo , Especificidade da Espécie , Virulência
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