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1.
J Chem Ecol ; 27(12): 2425-35, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11789949

RESUMO

Responses of the European spruce bark beetle, 1. typographus (Coleoptera: Scolytidae), to low release-rate pheromones were investigated in two experiments in a spruce forest at Wellin, southern Belgium. Dose-response of the beetle was first examined in a trapping experiment in August 1999. The major pheromone components of L. typographus, (S)-cis-verbenol (cV) and 2-methyl-3-buten-2-ol (MB) were released from window traps. Five treatments were replicated five times: (1) blank trap, (2) 0.03 and 1.2, (3) 0.11 and 4.5, (4) 0.34 and 15.2 mg/day of cV and MB, respectively, and (5) Pheroprax. Trap catches increased linearly as a function of increasing release rates of cV and MB. A second study aimed at making preliminary observations on the attraction range of the pheromones as compared to Pheroprax. A release-recapture experiment was carried out in May 2000: four trap-trees located 50 m away from a central release platform were equipped with window traps baited with increasing release rates, tested in separate releases: 0.03 and 1.2; 0.11 and 4.5; 0.34 and 15.2 mg/day of cV and MB, respectively, and Pheroprax. Recaptures increased with the release rate. Trap catches were different at lower release rates, but not between the release rate of 15.2 mg/day of MB and Pheroprax. Variations in captures in relation to wind parameters showed persistently random flight at the lower release rates. Significant upwind flight was observed for Pheroprax only. These results imply that trap interference existed for Pheroprax and suggest that its attraction range may be greater than 50 m.


Assuntos
Besouros/fisiologia , Hipnóticos e Sedativos/farmacologia , Monoterpenos , Movimento , Pentanóis/farmacologia , Feromônios/farmacologia , Terpenos/farmacologia , Animais , Monoterpenos Bicíclicos , Relação Dose-Resposta a Droga , Vento
2.
Am J Orthopsychiatry ; 70(1): 33-41, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10702848

RESUMO

Adaptive behavior and psychological well-being of African Americans can be affected by prejudice and discrimination. Encountering repeated racial slights can create "psychological invisibility." The invisibility syndrome is presented as a conceptual model for understanding the inner evaluative processes and adaptive behavior of African Americans in managing experiences of racism.


Assuntos
Adaptação Psicológica , Negro ou Afro-Americano/psicologia , Preconceito , Autoimagem , Adulto , Humanos , Masculino , Modelos Psicológicos , Síndrome
4.
Mol Cell Biol ; 14(10): 6773-88, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7935395

RESUMO

We report the fortuitous isolation of cDNA clones encoding a novel zinc finger DNA-binding protein termed BZP. The protein encoded is 114 kDa and contains eight zinc finger motifs, seven of which are present in two clusters at opposite ends of the molecule. Both finger clusters bound to the 9-bp sequence AAAGGTGCA with apparent Kds of approximately 2.5 nM. Two of the finger motifs within the amino- and carboxy-terminal finger clusters share 63% amino acid identity. BZP inhibited transcription of the herpes simplex virus thymidine kinase promoter when copies of the 9-bp target motif were linked in cis, suggesting that it functions as a transcriptional repressor. BZP mRNA and immunoreactivity were detected in several established cell lines but were most abundant in hamster insulinoma (HIT) cells, the parental source of the cDNAs. In mouse tissues, BZP mRNA and immunoreactivity were identified in cells of the endocrine pancreas, anterior pituitary, and central nervous system. Interestingly, in HIT cells proliferating in culture, BZP immunoreactivity was predominately nuclear in location, whereas it was usually located in the cytoplasm in most neural and neuroendocrine tissues. Serum deprivation of HIT cells caused BZP immunoreactivity to become predominantly cytoplasmic in location and attenuated its inhibitory effect on transcription, thereby suggesting that the both the subcellular location and the function of this protein are modulated by factors in serum.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas Repressoras , Fatores de Transcrição , Transcrição Gênica , Dedos de Zinco , Sequência de Aminoácidos , Animais , Sequência de Bases , Compartimento Celular , Sistema Nervoso Central/metabolismo , Clonagem Molecular , Meios de Cultura Livres de Soro , DNA Complementar/genética , Proteínas de Ligação a DNA/isolamento & purificação , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Ilhotas Pancreáticas/metabolismo , Camundongos , Dados de Sequência Molecular , Fragmentos de Peptídeos/metabolismo , Adeno-Hipófise/metabolismo , RNA Mensageiro/análise , Proteínas Recombinantes/metabolismo , Mapeamento por Restrição , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Distribuição Tecidual
6.
Mol Cell Biol ; 12(10): 4578-89, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1406648

RESUMO

beta-cell type-specific expression of the upstream glucokinase promoter was studied by transfection of fusion genes and analysis of DNA-protein interactions. A construct containing 1,000 bp of 5'-flanking DNA was efficiently expressed in HIT M2.2.2 cells, a beta-cell-derived line that makes both insulin and glucokinase, but not in NIH 3T3 cells, a heterologous cell line. In a series of 5' deletion mutations between bases -1000 and -100 (relative to a base previously designated +1), efficient expression in HIT cells was maintained until -280 bp, after which transcription decreased in a stepwise manner. The sequences between -180 and -1 bp contributing to transcriptional activity in HIT cells were identified by studying 28 block transversion mutants that spanned this region in 10-bp steps. Two mutations reduced transcription 10-fold or more, while six reduced transcription between 3- and 10-fold. Three mutationally sensitive regions of this promoter were found to bind to a factor that was expressed preferentially in pancreatic islet beta cells. The binding sites, designated upstream promoter elements (UPEs), shared a consensus sequence of CAT(T/C)A(C/G). Methylation of adenine and guanine residues within this sequence prevented binding of the beta-cell factor, as did mutations at positions 2, 3, and 5. Analysis of nuclear extracts from different cell lines identified UPE-binding activity in HIT M2.2.2 and beta-TC-3 cells but not in AtT-20, NIH 3T3, or HeLa cells; the possibility of a greatly reduced amount in alpha-TC-6 cells could not be excluded. UV laser cross-linking experiments supported the beta-cell type expression of this factor and showed it to be approximately 50 kDa in size. Gel mobility shift competition experiments showed that this beta-cell factor is the same that binds to similar elements, termed CT boxes, in the insulin promoter. Thus, a role for these elements (UPEs or CT boxes), and the beta-cell factor that binds to them, in determining the expression of genes in the beta cells of pancreatic islets is suggested.


Assuntos
Glucoquinase/genética , Ilhotas Pancreáticas/enzimologia , Regiões Promotoras Genéticas , Transcrição Gênica , Células 3T3 , Animais , Sequência de Bases , Clonagem Molecular , Cricetinae , DNA , Regulação Enzimológica da Expressão Gênica , Glucoquinase/metabolismo , Insulina/genética , Insulinoma , Camundongos , Dados de Sequência Molecular , Mutagênese , Especificidade de Órgãos/genética , Fatores de Transcrição/metabolismo , Transfecção , Células Tumorais Cultivadas
9.
Br Med J ; 4(5997): 614-7, 1975 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-1060502

RESUMO

Forty-two adults and children with previously untreated acute lymphoblastic leukaemia (ALL) were entered into a programme of chemotherapy in which three combinations, each of four drugs were administered in a predetermined cyclical rotation together with cranial irradiation and intrathecal injections of methotrexate. Forty-one patients (98%) entered remission and no patient developed neuroleukaemia. Relapse of ALL occurred in 10 patients, and three patients died during remission, while eight patients stopped treatment after two and a half years and have remained in remission for two to 26 months. Comparison of remission and survival experience in this mixed group of children and adults with the experience of children treated at Memphis and in the Medical Research Council's UKALL-I trial showed no significant differences. On the other hand, analysis by prognostic factors showed that neither age nor blast cell count at presentation had any adverse effect in patients treated in this study. No relapses occurred in nine patients with blast cell counts greater than 20 x 109/1 at presentation. This regimen is effective treatment for ALL and may be of special value in patients with poor prognoses. The regiment has not as yet proved superior for the treatment of children with ALL who do not have adverse prognostic features.


Assuntos
Antineoplásicos/uso terapêutico , Leucemia Linfoide/tratamento farmacológico , Adolescente , Adulto , Antineoplásicos/efeitos adversos , Asparaginase/uso terapêutico , Contagem de Células Sanguíneas , Criança , Pré-Escolar , Ciclofosfamida/uso terapêutico , Citarabina/uso terapêutico , Daunorrubicina/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Leucemia Linfoide/radioterapia , Masculino , Metotrexato/uso terapêutico , Prednisolona/uso terapêutico , Prognóstico , Remissão Espontânea , Tioguanina/uso terapêutico , Vincristina/uso terapêutico
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