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1.
J Endocrinol Invest ; 46(4): 787-794, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36441505

RESUMO

PURPOSE: Weight stigma is the negative weight related attitudes and beliefs towards individuals because of their overweight or obesity. Subjects with obesity are often victim of weight-related stigma resulting in a significant negative social consequence. As obesity epidemic is growing so fast, there is urgency to act on weight-stigma related social consequences being potentially serious and pervasive. This study investigated experiences, interpersonal sources, and context of weight stigma in Italy in a sample of adult subjects with obesity. METHODS: An online questionnaire was distributed to respondents via a snowball sampling method among subjects with obesity belonging to Italian Associations for people living with obesity aged 18 years and above. RESULTS: Four hundred and three respondents (47.18 ± 9.44 years; body mass index (BMI) 33.2 ± 8.48 kg/m2) participated to the study. Most respondents were females (94.8%). The age first dieted was 15.82 ± 7.12 years. The mean period of obesity was 27.49 ± 11.41 years. Frequency analyses reported that stigmatizing situations were experienced by 98% of participants: 94.82% during adulthood, 89.88% during adolescence and 75.39% during childhood. Verbal mistreatments (92.43%) was the most reported stigmatizing situation, strangers (92.43%) were the most common interpersonal sources of stigma and public settings (88.08%) were the most common location of stigma. CONCLUSIONS: Identifying strategies acting on the identified weight stigma targets could contribute to reduce weight stigma and thus to result in important implications for obesity treatment in Italy.


Assuntos
Preconceito de Peso , Adulto , Feminino , Adolescente , Humanos , Masculino , Obesidade/epidemiologia , Sobrepeso , Estigma Social , Índice de Massa Corporal , Peso Corporal
2.
Z Rheumatol ; 81(8): 682-685, 2022 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-35348848

RESUMO

This article describes a hantavirus-associated pronounced myositis as a rare differential diagnosis to polymyositis. The literature on the pathogenesis of hantavirus disease discusses less a direct viral cytopathology but more a secondary immune dysregulation with induction of a capillary leak. This article describes for the first time a case of successful treatment of protracted hantavirus myositis using high-dose glucocorticoids and cyclophosphamide, followed by ciclosporin and MTX.


Assuntos
Miosite , Polimiosite , Ciclofosfamida/uso terapêutico , Ciclosporina/uso terapêutico , Glucocorticoides/uso terapêutico , Humanos , Miosite/diagnóstico , Polimiosite/diagnóstico , Polimiosite/tratamento farmacológico , Polimiosite/patologia
3.
Scand J Immunol ; 76(4): 440-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22803655

RESUMO

The objective of this study was to investigate human leucocyte antigen (HLA) genes in patients chronically infected with hepatitis C virus (HCV) and to analyse the possible role of these genes in the progression of chronic hepatitis C. One hundred and forty-five (145) Brazilian patients infected only with HCV genotype 1 were evaluated. HLA class I (A, B, C) and class II (DRB1, DQA1, DQB1) typing were carried out by PCR-SSO, through Luminex technology. Associations were found with protection against development of liver damage by both DRB1 11 (5.0% versus 18.2%, P=0.0016, OR=0.23, CI 95% = 0.09-0.58; Pc=0.0208) and DRB1 11-DQA1 05-DQB1 03 haplotype (4.2% versus 15.3%, P=0.0032; OR = 0.24, CI 95% = 0.08-0.64). Liver damage was associated with HLA-C 04 in patients with <20 years of infection (38.4% versus 9.1%, P = 0.002, OR = 6.25, CI 95%=1.97-19.7; Pc=0.0238). It is concluded that HLA alleles can influence the development of liver damage in HCV type-1 chronically infected Brazilian patients.


Assuntos
Antígenos HLA-C/genética , Cadeias HLA-DRB1/genética , Hepatite C Crônica/imunologia , Cirrose Hepática/imunologia , Fígado/imunologia , Adulto , Alelos , Brasil , Feminino , Frequência do Gene , Predisposição Genética para Doença , Antígenos HLA-C/imunologia , Cadeias HLA-DRB1/imunologia , Haplótipos , Hepatite C Crônica/complicações , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Imunofenotipagem , Fígado/patologia , Fígado/virologia , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fatores de Tempo
4.
Int J Immunogenet ; 39(4): 296-302, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22284614

RESUMO

The objective of this study was to analyse the possible role of HLA polymorphism of chronically infected hepatitis C virus patients in the response outcome to treatment with pegylated interferon-alpha plus ribavirin. To that end, 144 Brazilian patients infected only with genotype 1 of the virus were treated with pegylated interferon-alpha at 1.5 µg kg(-1) in conjunction with ribavirin (1000 mg if patient weight was <75 kg and 1250 mg if >75 kg) for 48 weeks. The patients did not have concomitant HBV or HIV infections or liver disease, did not undergo previous antiviral treatment, and were followed up for 24 weeks after the end of treatment to assure they presented a sustained virological response. Patients were classified according to response to treatment in responsive (SVR), nonresponsive (NRS) and relapsers (REL). HLA class I and class II typing were carried out through PCR-SSO using Luminex technology. A statistically higher frequency of DRB1*11 patients was observed in the SVR group (39.6% vs. 14.3%P = 0.0012; Pc = 0.0156; OR = 3.94; 95% CI = 1.8-8.8). HLA-DQB1*03 patients were also more frequent in the SVR group, but the P value lost significance after Bonferroni correction (62.3% vs. 41.7%P = 0.024; Pc = 0.14, OR = 2.3; 95% CI = 1.14-4.60). HLA class II antigens can positively influence the response to treatment with pegylated interferon-alpha and ribavirin.


Assuntos
Alelos , Genes MHC da Classe II , Genes MHC Classe I , Hepatite C Crônica/genética , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Quimioterapia Combinada/métodos , Feminino , Seguimentos , Genótipo , Cadeias HLA-DRB1/genética , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Teste de Histocompatibilidade/métodos , Humanos , Interferon-alfa/administração & dosagem , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Recidiva , Ribavirina/administração & dosagem , Resultado do Tratamento
5.
Eat Weight Disord ; 12(3): 108-13, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17984634

RESUMO

The aims of the study were to test the hypotheses that some symptoms of starvation/severe dietary restraint are interpreted by patients with eating disorders in terms of control. Sixty-nine women satisfying the Diagnostic and Statistical Manual of Mental Disorders-IV edition (DSM-IV) criteria for a clinical eating disorder and 107 controls participated in the study. All the participants completed an ambiguous scenarios paradigm, the Eating Disorder Examination Questionnaire (EDE-Q) and the Beck Depression Inventory (BDI). Significantly more eating disorder patients than non clinical participants interpreted the starvation/dietary restraint symptoms of hunger, heightened satiety, and dizziness in terms of control. The data give further support to the recent cognitive-behavioural theory of eating disorders suggesting that eating disorder patients interpret some starvation/dietary restraint symptoms in terms of control.


Assuntos
Comportamento Alimentar , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Teoria Psicológica , Inanição/psicologia , Adulto , Índice de Massa Corporal , Terapia Cognitivo-Comportamental , Depressão/diagnóstico , Depressão/epidemiologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Transtornos da Alimentação e da Ingestão de Alimentos/terapia , Feminino , Humanos , Inquéritos e Questionários
6.
Development ; 127(4): 881-92, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10648246

RESUMO

OVO controls germline and epidermis differentiation in flies and mice. In the Drosophila germline, alternative OVO-B and OVO-A isoforms have a common DNA-binding domain, but different N-termini. We show that these isoforms are transcription factors with opposite regulatory activities. Using yeast one-hybrid assays, we identified a strong activation domain within a common region and a counteracting repression domain within the OVO-A-specific region. In flies, OVO-B positively regulated the ovarian tumor promoter, while OVO-A was a negative regulator of the ovarian tumor and ovo promoters. OVO-B isoforms supplied ovo(+) function in the female germline and epidermis, while OVO-A isoforms had dominant-negative activity in both tissues. Moreover, elevated expression of OVO-A resulted in maternal-effect lethality while the absence of OVO-A resulted in maternal-effect sterility. Our data indicate that tight regulation of antagonistic OVO-B and OVO-A isoforms is critical for germline formation and differentiation.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila , Drosophila/crescimento & desenvolvimento , Drosophila/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Proteínas de Ligação a DNA/genética , Drosophila/genética , Feminino , Genes Reporter , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Camundongos , Modelos Biológicos , Dados de Sequência Molecular , Oogênese , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Regiões Promotoras Genéticas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética
7.
Chromosoma ; 109(7): 453-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11151674

RESUMO

We have constructed a new reporter transgene, Winkelried, equipped with a synthetic binding site for the yeast GAL4 transcriptional activator. The binding site is inserted between the white and lacZ reporter genes, and is flanked by FRT sequences. These elements allow excision of the GAL4 binding site by crossing the transgenic line with an FLP recombinase producing strain. We have generated by X-ray irradiation two independent chromosomal rearrangements, Heidi and Tell, relocating Winkelried next to pericentromeric heterochromatin. These rearrangements induce variegation of both white and lacZ. Variegation of Winkelried in the rearranged transgenic lines responds to the loss and excess of doses of the dominant suppressors of position-effect variegation (PEV) Su(var)3-7 and Su(var)2-5. Winkelried therefore constitutes a unique tool to test the effect on variegation in cis of any factor fused to the GAL4 DNA binding domain. Indeed, a chimeric protein, made of the DNA binding site of GAL4 and of HP1, the modifier of PEV encoded by Su(var)2-5, is shown to enhance variegation of Heidi and Tell. Excision of the binding sites for GAL4 in the variegating rearrangements Heidi and Tell abolishes the modifier effect of the GAL4-HP1 chimera. Therefore, in the Heidi and Tell rearrangements, enhancement of position-effect variegation depends strictly both on the concentration of GAL4-HP1 and on the presence of its binding site in the vicinity of the reporter genes.


Assuntos
Proteínas de Ligação a DNA , Proteínas Fúngicas/metabolismo , Inativação Gênica , Heterocromatina/metabolismo , Proteínas Nucleares , Proteínas Recombinantes de Fusão/metabolismo , Proteínas de Saccharomyces cerevisiae , Fatores de Transcrição/metabolismo , Sequência de Bases , Sítios de Ligação , Primers do DNA , Proteínas Fúngicas/genética , Fator 1 Nuclear de Hepatócito , Fator 1-beta Nuclear de Hepatócito , Fenótipo , Fatores de Transcrição/genética , Transgenes
8.
Development ; 126(9): 1917-26, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10101125

RESUMO

The Drosophila gene stand still (stil) encodes a novel protein required for survival, sexual identity and differentiation of female germ cells. Using specific antibodies, we show that the Stil protein accumulates in the nucleus of all female germ cells throughout development, and is transiently expressed during early stages of male germline differentiation. Changes of Stil subnuclear localization during oogenesis suggest an association with chromatin. Several mutant alleles, which are point mutations in the Stil N-terminal domain, encode proteins that no longer co-localized with chromatin. We find that Stil binds to many sites on polytene chromosomes with strong preference for decondensed chromatin. This localization is very similar to that of RNA polymerase II. We show that Stil is required for high levels of transcription of the ovarian tumor gene in germ cells. Expression of ovarian tumor in somatic cells can be induced by ectopic expression of Stil. Finally, we find that transient ubiquitous somatic expression of Stil results in lethality of the fly at all stages of development.


Assuntos
Cromatina/genética , Proteínas de Drosophila , Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Insetos/genética , Proteínas Nucleares , Óvulo/fisiologia , Animais , Núcleo Celular/fisiologia , Mapeamento Cromossômico , Drosophila melanogaster/embriologia , Drosophila melanogaster/crescimento & desenvolvimento , Embrião não Mamífero/fisiologia , Feminino , Genes Letais , Proteínas de Choque Térmico HSP70/biossíntese , Proteínas de Choque Térmico HSP70/genética , Proteínas de Insetos/biossíntese , Masculino , Ovário/fisiologia , Óvulo/citologia , Mutação Puntual , Proteínas Recombinantes de Fusão/biossíntese , Diferenciação Sexual
9.
Dev Genes Evol ; 208(9): 531-6, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9799435

RESUMO

Expression of many mammalian genes is activated by the binding of heterodimers of the Myc and Max proteins to specific DNA sequences called the E-boxes. Transcription of the same genes is repressed upon binding to the same sequences of complexes composed of Max, Mad/Mxi1, the co-repressors Sin3 and N-CoR, and the histone deacetylase Rpd3. Max-Mad/Mxi1 heterodimers, which bind to E-boxes in absence of co-repressors, do not inhibit gene expression simply by competition with Myc-Max heterodimers, but require Sin3 and Rpd3 for efficient repression of transcription. We have cloned a Drosophila homolog of Sin3 (dSin3) and found it to be ubiquitously expressed during embryonic development. Yeast, mouse and Drosophila proteins share six blocks of strong homologies, including four potential paired amphipathic helix domains. In addition, the domain of binding to the histone deacetylase Rpd3 is strongly conserved. Null mutations cause recessive embryonic lethality.


Assuntos
Drosophila/genética , Embrião não Mamífero , Proteínas Repressoras , Proteínas de Saccharomyces cerevisiae , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Drosophila/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Histona Desacetilases , Camundongos , Dados de Sequência Molecular , Mutação , Saccharomyces cerevisiae/genética , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/química
10.
Dev Genes Evol ; 208(4): 213-22, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9634487

RESUMO

The ovo+ and ovarian tumor+ genes function in the germline sex determination pathway in Drosophila, but the hierarchical relationship between them is unknown. We found that increased ovo+ copy number resulted in increased ovarian tumor expression in the female germline and increased ovo expression in the male germline. The ovo locus encodes C2H2 zinc-finger proteins. Bacterially expressed OVO zinc-finger domain bound to multiple sites at or near the ovo and ovarian tumor promoters strongly suggesting that OVO is directly autoregulatory and that ovarian tumor is a direct downstream target of ovo in the germline sex determination hierarchy. Both positive and negative regulation by OVO proteins appears likely, depending on promoter context and on the sex of the fly. Our observation that two strong OVO-binding sites are at the initiator of the TATA-less ovo-B and ovarian tumor promoters raises the possibility that OVO proteins influence the nucleation of transcriptional pre-initiation complexes.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Drosophila , Drosophila/genética , Regulação da Expressão Gênica , Genes de Insetos , Proteínas de Insetos/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Feminino , Masculino , Dados de Sequência Molecular , Oogênese/genética , Regiões Promotoras Genéticas/genética , Espermatogênese/genética , Dedos de Zinco/genética
11.
Mol Cell Biol ; 18(4): 1835-43, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9528755

RESUMO

We report the cloning of the noisette gene (noi), which encodes the Drosophila melanogaster ortholog of a U2 snRNP-associated splicing factor, SF3a60 (SAP61) in humans and PRP9p in Saccharomyces cerevisiae. Antibodies raised against human SF3a60 recognized NOI in flies, showing a nuclear localization in all the stages examined, including the embryo, the dividing cells of imaginal discs, and the larval polyploid nuclei. NOI is expressed in somatic and germinal cells of both male and female gonads. By mobilization of P transposons, we have generated a large number of noi mutations. Complete loss of function resulted in lethality at the end of embryogenesis, without obvious morphological defects. Hypomorphic alleles revealed multiple roles of noi for the survival and differentiation of male germ cells, the differentiation of female germ cells, and the development of several adult structures.


Assuntos
Proteínas de Ligação a DNA/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/genética , Proteínas de Ligação a RNA/genética , Ribonucleoproteína Nuclear Pequena U2/metabolismo , Fatores de Transcrição/genética , Alelos , Animais , Mapeamento Cromossômico , Clonagem Molecular , Elementos de DNA Transponíveis , Proteínas de Ligação a DNA/metabolismo , Feminino , Humanos , Masculino , Mutação , Fator de Transcrição PAX2 , Proteínas de Ligação a RNA/metabolismo , Processos de Determinação Sexual , Fatores de Transcrição/metabolismo , Dedos de Zinco
12.
Dev Genet ; 23(4): 335-46, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9883585

RESUMO

Mutations in ovo result in several different phenotypes, which we show are due to the regulation of distinct developmental pathways. Two X (female) germ cells require ovo+ activity for viability, but 1X (male) germ cells do not. In our study, we observed suppression of the ovo germline-lethality phenotype in loss-of-function maleless (mle) females indicating that ovo+ and mle+ have opposing effects in female germ cells; or that they are hierarchically related. Gain-of-function Sex-lethal (Sxl) alleles and male specific lethal-2 alleles did not suppress the ovo germline death phenotype. Many of the surviving germ cells in females mutant for both ovo and mle showed ovarian tumors. In contrast to the germline viability phenotype, we did observe suppression of the tumor phenotype in females heterozygous for gain-of-function alleles of Sxl. Further, females mutant for some hypomorphic ovo alleles were rendered fertile by Sxl gain-of-function alleles. Thus, ovo+ is required for at least two distinct functions, one involving mle+, and one mediated by Sxl+ gene products. The existence of ovo+ functions independent of mle+ and Sxl+ is likely.


Assuntos
Proteínas Cromossômicas não Histona , DNA Helicases , Proteínas de Ligação a DNA , Proteínas de Drosophila , Drosophila/embriologia , Drosophila/genética , Regulação da Expressão Gênica no Desenvolvimento , Oogênese/genética , RNA Helicases/genética , Proteínas de Ligação a RNA/genética , Processos de Determinação Sexual , Fatores de Transcrição/genética , Animais , Feminino , Genes de Insetos , Proteínas de Insetos/genética , Masculino
13.
Genetics ; 145(4): 975-87, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9093851

RESUMO

We identified a new gene, stand still (stil), required in the female germline for proper survival, sex determination and differentiation. Three strong loss-of-function alleles were isolated. The strongest phenotype exhibited by ovaries dissected from adult females is the complete absence of germ cells. In other ovaries, the few surviving germ cells frequently show a morphology typical of primary spermatocytes. stil is not required either for fly viability or for male germline development. The gene was cloned and found to encode a novel protein. stil is strongly expressed in the female germ cells. Using P[stil+] transgenes, we show that stil and a closely localized gene are involved in the modification of the ovarian phenotypes of the dominant alleles of ovo caused by heterozygosity of region 49 A-D. The similarity of the mutant phenotypes of stil to that of otu and ovo suggests that the three genes function in a common or in parallel pathways necessary in the female germline for its survival, sex determination and differentiation.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster/genética , Genes de Insetos , Proteínas de Insetos/genética , Proteínas Nucleares , Alelos , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/genética , Feminino , Regulação da Expressão Gênica , Infertilidade Feminina/genética , Infertilidade Feminina/patologia , Proteínas de Insetos/fisiologia , Masculino , Dados de Sequência Molecular , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Ovário/patologia , Fenótipo , Análise para Determinação do Sexo , Diferenciação Sexual
14.
Nature ; 384(6609): 589-91, 1996 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-8955276

RESUMO

Both position-effect variegation (PEV) in Drosophila and telomeric position-effect in yeast (TPE) result from the mosaic inactivation of genes relocated next to a block of centromeric heterochromatin or next to telomeres. In many aspects, these phenomena are analogous to other epigenetic silencing mechanisms, such as the control of homeotic gene clusters, X-chromosome inactivation and imprinting in mammals, and mating-type control in yeast. Dominant mutations that suppress or enhance PEV are thought to encode either chromatin proteins or factors that directly affect chromatin structure. We have identified an insertional mutation in Drosophila that enhances PEV and reduces transcription of the gene in the eye-antenna imaginal disc. The gene corresponds to that encoding the transcriptional regulator RPD3 in yeast, and to a human histone deacetylase. In yeast, RRD3-deletion strains show enhanced TPE, suggesting a conserved role of the histone deacetylase RPD3 in counteracting genomic silencing. This function of RPD3, which is in contrast to the general correlation between histone acetylation and increased transcription, might be due to a specialized chromatin structure at silenced loci.


Assuntos
Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Regulação da Expressão Gênica , Genes de Insetos , Histona Desacetilases/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Clonagem Molecular , Elementos de DNA Transponíveis , Proteínas de Drosophila , Drosophila melanogaster , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Histona Desacetilase 1 , Histona Desacetilases/química , Histona Desacetilases/genética , Humanos , Dados de Sequência Molecular , Mutagênese Insercional , Proteínas Repressoras , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae , Telômero/fisiologia , Fatores de Transcrição/química , Fatores de Transcrição/genética
15.
Mol Cell Biol ; 16(10): 5717-25, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8816485

RESUMO

A dominant insertional P-element mutation enhances position-effect variegation in Drosophila melanogaster. The mutation is homozygous, viable, and fertile and maps at 64E on the third chromosome. The corresponding gene was cloned by transposon tagging. Insertion of the transposon upstream of the open reading frame correlates with a strong reduction of transcript level. A transgene was constructed with the cDNA and found to have the effect opposite from that of the mutation, namely, to suppress variegation. Sequencing of the cDNA reveals a large open reading frame encoding a putative ubiquitin-specific protease (Ubp). Ubiquitin marks various proteins, frequently for proteasome-dependent degradation. Ubps can cleave the ubiquitin part from these proteins. We discuss the link established here between a deubiquitinating enzyme and epigenetic silencing processes.


Assuntos
Mapeamento Cromossômico , Drosophila melanogaster/enzimologia , Drosophila melanogaster/genética , Endopeptidases/genética , Endopeptidases/metabolismo , Transcrição Gênica , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Sequência de Bases , Cruzamentos Genéticos , Embrião não Mamífero , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Genes Homeobox , Genes de Insetos , Homozigoto , Masculino , Dados de Sequência Molecular , Mutagênese Insercional , Fases de Leitura Aberta , Pigmentação , Recombinação Genética , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos
16.
Development ; 122(6): 1949-56, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8674433

RESUMO

A dominant mutation due to the insertion of a P-element at 93E on the third chromosome of Drosophila melanogaster enhances position-effect variegation. The corresponding gene was cloned by transposon tagging and the sequence of the transcript revealed that it corresponds to the gene encoding the transcriptional activator and cell cycle regulator dE2F. The transposon-tagged allele is homozygous viable, and the insertion of the transposon in an intron correlates with a strong reduction in the amount of transcript. A homozygous lethal null allele was found to behave as a strong enhancer when heterozygous. Overexpression of the gene in transgenic flies has the opposite effect of suppressing variegation. A link is established here, and discussed, between the dose of a transcriptional activator, which controls the cell cycle, and epigenetic silencing of chromosomal domains in Drosophila.


Assuntos
Proteínas de Transporte , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA , Proteínas de Drosophila , Drosophila melanogaster/genética , Cor de Olho/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Ciclo Celular/metabolismo , Clonagem Molecular , DNA , Drosophila melanogaster/embriologia , Fatores de Transcrição E2F , Elementos Facilitadores Genéticos , Feminino , Dosagem de Genes , Regulação da Expressão Gênica , Hormônios de Inseto , Masculino , Dados de Sequência Molecular , Mutação , RNA Mensageiro/metabolismo , Proteína 1 de Ligação ao Retinoblastoma , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/metabolismo
17.
Genetics ; 139(2): 713-32, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7713427

RESUMO

Only a few Drosophila melanogaster germline sex determination genes are known, and there have been no systematic screens to identify new genes involved in this important biological process. The ovarian phenotypes produced by females mutant for dominant alleles of the ovo gene are modified in flies with altered doses of other loci involved in germline sex determination in Drosophila (Sex-lethal+, sans fille+ and ovarian tumor+). This observation constitutes the basis for a screen to identify additional genes required for proper establishment of germline sexual identity. We tested 300 deletions, which together cover approximately 58% of the euchromatic portion of the genome, for genetic interactions with ovoD. Hemizygosity for more than a dozen small regions show interactions that either partially suppress or enhance the ovarian phenotypes of females mutant for one or more of the three dominant ovo mutations. These regions probably contain genes whose products act in developmental hierarchies that include ovo+ protein.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Drosophila , Genes de Insetos/fisiologia , Oogênese/genética , Proteínas de Ligação a RNA , Diferenciação Sexual/genética , Fatores de Transcrição/genética , Alelos , Animais , Cruzamentos Genéticos , Drosophila melanogaster/genética , Feminino , Hormônios de Inseto/genética , Masculino , Fenótipo , Deleção de Sequência/fisiologia , Supressão Genética , Cromossomo X
18.
Development ; 120(11): 3185-95, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7720561

RESUMO

Germ-line sex determination in Drosophila melanogaster requires an assessment of the number of X chromosomes as measured against autosomal standards (XX = female, X = male) and signaling from the soma. Both of these sex determination cues are required for female-specific Sex-lethal+ function in germ cells. The ovo+ locus encodes zinc finger protein(s) required for female-specific splicing of Sex-lethal+ pre-mRNA, making ovo+ a candidate function acting between the two principal cues and Sex-lethal+. We have made ovo reporter genes and find that they show high activity in the germ line of females and low activity in the germ line of males. XY flies transformed into somatic females do not show high levels of reporter activity, while XX flies transformed into somatic males do. This shows that high level ovo+ expression depends on the number of X chromosomes, not the somatic sexual signals. The requirement for ovo+ function is restricted to XX flies. Mutations in ovo have no effect on XY males, X0 males or XY females, but have pronounced effects on germ cell viability in XX females, XX females with sex transformed germ lines, and XX males indicating that ovo+ gene products are required for events occurring only in flies with two X chromosomes.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Drosophila , Drosophila melanogaster/genética , Genes de Insetos/fisiologia , Análise para Determinação do Sexo , Fatores de Transcrição/genética , Cromossomo X , Animais , Mapeamento Cromossômico , Feminino , Expressão Gênica , Humanos , Masculino , Modelos Biológicos , Ovário/fisiologia
19.
Rev Inst Med Trop Sao Paulo ; 36(1): 27-32, 1994.
Artigo em Português | MEDLINE | ID: mdl-7997770

RESUMO

Twenty seven cases of neurocysticercosis, with clinical picture of acute meningitis, are described. Twenty (74.1%) patients are male; the age was 4 to 42 years (23.6 +/- 11.7 years). The etiologic diagnosis was defined by the complement fixation test (Weinberg) and/or enzyme-linked immunosorbent assay (ELISA) for cysticercosis in the cerebrospinal fluid (c. s. f.). Six patients that realized cranial computerized tomographic scan resembling neurocysticercosis. Twenty one (77.8%) have predominance of lymphomononuclear cells in the c. s. f. obtained in the admission to the hospital; in 6 (22.2%) there were predominance of polymorphonuclear neutrophils. In this c. s. f. lymphomononuclear pleocytosis and in three that have c. s. f. neutrophil pleocytosis, suggesting the diagnosis of neurocysticercosis. The treatment of acute neurocysticercosis was made with dexamethasone. All the patients survived and were transferred to the ambulatory of Neurology for follow-up and complementary treatment.


Assuntos
Encefalopatias/diagnóstico , Cisticercose/diagnóstico , Doença Aguda , Adolescente , Adulto , Encefalopatias/líquido cefalorraquidiano , Encefalopatias/complicações , Criança , Pré-Escolar , Testes de Fixação de Complemento , Cisticercose/líquido cefalorraquidiano , Cisticercose/complicações , Diagnóstico Diferencial , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Leucócitos , Masculino , Meningite/líquido cefalorraquidiano , Meningite/diagnóstico , Meningite/parasitologia
20.
Dev Biol ; 161(1): 318-20, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8293883

RESUMO

Mutations at a few genetic loci in Drosophila cause ovarian tumors with hundreds of poorly differentiated germ cells. We examined several of these mutants to test the hypothesis that such ovarian tumors contain sex-transformed cells. By testing for expression of male germline traits, we determined that partial germline sex transformation occurs in otu, snf, Sxlfs, and bam ovarian tumors. Thus these genes are likely to be required for proper establishment of germline sexual identity.


Assuntos
Drosophila/genética , Células Germinativas/fisiologia , Análise para Determinação do Sexo , Animais , Feminino , Masculino , Mutação , Neoplasias Ovarianas/genética , Tubulina (Proteína)/genética
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