RESUMO
The prevalence of neurodevelopmental disorders such as autism is increasing, however the etiology of these disorders is unclear and thought to involve a combination of genetic, environmental and immune factors. A recent epidemiological study found that gestational viral exposure during the first trimester increases risk of autism in offspring by twofold. In mice gestational viral exposures alter behavior of offspring, but the biological mechanisms which underpin these behavioral changes are unclear. We hypothesized that gestational viral exposure induces changes in affiliative hormones, brainstem autonomic nuclei and neurotransmitters which are associated with behavioral alterations in offspring. To address this hypothesis, we exposed pregnant mice to influenza A virus (H3N2) on gestational day 9 and determined behavioral, hormonal and brainstem changes in male and female offspring. We found that gestational flu exposure induced dose-dependent alterations in social and aggressive behaviors (p≤0.05) in male and female offspring and increases in locomotor behaviors particularly in male offspring (p≤0.05). We found that flu exposure was also associated with reductions in oxytocin and serotonin (p≤0.05) levels in male and female offspring and sex-specific changes in dopamine metabolism. In addition we found changes in catecholaminergic and microglia density in brainstem tissues of male flu exposed offspring only (p≤0.05). This study demonstrates that gestational viral exposure induces behavioral changes in mice, which are associated with alterations in affiliative hormones. In addition we found sex-specific changes in locomotor behavior, which may be associated with sex-specific alterations in dopamine metabolism and brainstem inflammation. Further investigations into maternal immune responses are necessary to unravel the molecular mechanisms which underpin abnormal hormonal, immune and behavioral responses in offspring after gestational viral exposure.
Assuntos
Transtorno Autístico/etiologia , Tronco Encefálico/imunologia , Tronco Encefálico/patologia , Vírus da Influenza A Subtipo H3N2 , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia , Ocitocina/sangue , Testosterona/sangue , Animais , Transtorno Autístico/imunologia , Transtorno Autístico/patologia , Glicemia/análise , Peso Corporal/imunologia , Tronco Encefálico/virologia , Cromatografia Líquida de Alta Pressão , Feminino , Inflamação/imunologia , Inflamação/patologia , Inflamação/virologia , Masculino , Exposição Materna/efeitos adversos , Camundongos , Camundongos Endogâmicos BALB C , Atividade Motora/imunologia , Infecções por Orthomyxoviridae/complicações , Projetos Piloto , Gravidez , Distribuição Aleatória , Comportamento EstereotipadoRESUMO
The sites of transcript accumulation for six different homeotic loci of the Antennapedia and bithorax gene complexes (ANT-C and BX-C) were identified within embryo tissue sections by in situ hybridization. These six loci belong to the Antennapedia class of the homeo box gene family. Transcripts encoded by each locus are detected primarily in discrete, nonoverlapping regions of the embryonic central nervous system (CNS). The regions of the CNS that contain transcripts encoded by each of these loci correspond to the embryonic segments that are disrupted in mutants for these genes. The maintenance of spatially restricted expression of each ANT-C and BX-C locus could involve hierarchical, cross-regulatory interactions that are mediated by the homeo box protein domains encoded by these genes.
Assuntos
Drosophila/genética , Regulação da Expressão Gênica , Genes , Animais , Sistema Nervoso Central/crescimento & desenvolvimento , Mapeamento Cromossômico , Clonagem Molecular , Drosophila/crescimento & desenvolvimento , Drosophila/fisiologia , Hibridização de Ácido Nucleico , Transcrição GênicaRESUMO
Mammalian homeo box genes have been identified on the basis of sequence homology to Drosophila homeotic and segmentation genes. These studies examine the distribution of transcripts from two mouse homeo box genes, Hox-2.1 and Hox-3.1, throughout the latter third of prenatal development. Transcripts from these genes are regionally localized along the rostro-caudal axis of the developing central nervous system, yielding expression patterns very similar to patterns of Drosophila homeotic gene expression.
Assuntos
Regulação da Expressão Gênica , Genes Homeobox , Animais , Animais Recém-Nascidos/genética , Sequência de Bases , Encéfalo/metabolismo , Diferenciação Celular , Drosophila melanogaster/genética , Feto/metabolismo , Camundongos , Morfogênese , Hibridização de Ácido Nucleico , Medula Espinal/metabolismo , Transcrição GênicaRESUMO
Research published in the past year has led to plausible molecular models explaining the maintenance of stable patterns of homeotic gene expression through many cell generations. In addition, genes have been identified that modify the functional specificity of homeotic genes without affecting their expression patterns.
Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Drosophila , Drosophila/embriologia , Regulação da Expressão Gênica , Genes Homeobox , Proteínas de Homeodomínio , Proteínas Nucleares , Fatores de Transcrição , Animais , Proteína do Homeodomínio de Antennapedia , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/fisiologia , Drosophila/genética , Embrião não Mamífero/ultraestrutura , Morfogênese/genéticaRESUMO
PURPOSE: To determine whether a sucralfate oral solution can prevent/alleviate radiation-induced esophagitis. PATIENTS AND METHODS: Patients included on this clinical trial were beginning thoracic radiation therapy to the mediastinum. Following stratification, they were randomized, in a double-blind manner, to receive a sucralfate solution or an identical-appearing placebo solution. Esophagitis was measured by physicians who used standard criteria and also by patients who used short questionnaires completed weekly during the course of the trial. RESULTS: A total of 97 assessable patients were entered onto this clinical trial. During the first 2 weeks of the study, two placebo patients (4%) stopped their study medication, compared with 20 sucralfate patients (40%). This was related to substantially increased incidences of gastrointestinal toxicity (58% of sucralfate patients v 14% of placebo patients; P > .0001). There was no substantial benefit from the sucralfate in terms of esophagitis scores. CONCLUSION: This oral sucralfate solution does not appear to inhibit radiation-induced esophagitis and is associated with disagreeable gastrointestinal side effects in this patient population.
Assuntos
Antiulcerosos/uso terapêutico , Esofagite/tratamento farmacológico , Lesões por Radiação/tratamento farmacológico , Sucralfato/uso terapêutico , Administração Oral , Idoso , Esofagite/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/prevenção & controleRESUMO
We have screened the Drosophila X chromosome for genes whose dosage affects the function of the homeotic gene Deformed. One of these genes, extradenticle, encodes a homeodomain transcription factor that heterodimerizes with Deformed and other homeotic Hox proteins. Mutations in the nejire gene, which encodes a transcriptional adaptor protein belonging to the CBP/p300 family, also interact with Deformed. The other previously characterized gene identified as a Deformed interactor is Notch, which encodes a transmembrane receptor. These three genes underscore the importance of transcriptional regulation and cell-cell signaling in Hox function. Four novel genes were also identified in the screen. One of these, rancor, is required for appropriate embryonic expression of Deformed and another homeotic gene, labial. Both Notch and nejire affect the function of another Hox gene, Ultrabithorax, indicating they may be required for homeotic activity in general.
Assuntos
Drosophila/genética , Regulação da Expressão Gênica no Desenvolvimento , Genes de Insetos , Proteínas de Homeodomínio/genética , Mutação , Cromossomo X , Animais , Proteínas de Drosophila , Feminino , Testes Genéticos , Proteínas de Homeodomínio/fisiologia , Masculino , FenótipoRESUMO
Proteins produced by the homeotic genes of the Hox family assign different identifies to cells on the anterior/posterior axis. Relatively little is known about the signalling pathways that modulate their activities or the factors with which they interact to assign specific segmental identifies. To identify genes that might encode such functions, we performed a screen for second site mutations that reduce the viability of animals carrying hypomorphic mutant alleles of the Drosophila homeotic locus, Deformed. Genes mapping to six complementation groups on the third chromosome were isolated as modifiers of Deformed function. Products of two of these genes, sallimus and moira, have been previously proposed as homeotic activators since they suppress the dominant adult phenotype of Polycomb mutants. Mutations in hedgehog, which encodes secreted signalling proteins, were also isolated as Deformed loss-of-function enhancers. Hedgehog mutant alleles also suppress the Polycomb phenotype. Mutations were also isolated in a few genes that interact with Deformed but not with Polycomb, indicating that the screen identified genes that are not general homeotic activators. Two of these genes, cap 'n' collar and defaced, have defects in embryonic head development that are similar to defects seen in loss of function Deformed mutants.
Assuntos
Proteínas de Drosophila , Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/fisiologia , Fatores de Transcrição , Animais , Mapeamento Cromossômico , Cruzamentos Genéticos , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/fisiologia , Drosophila melanogaster/embriologia , Feminino , Genes Dominantes , Genes Letais , Teste de Complementação Genética , Cabeça/embriologia , Proteínas Hedgehog , Proteínas de Homeodomínio/genética , Masculino , Morfogênese/genética , Fenótipo , Complexo Repressor Polycomb 1 , Proteínas/genética , Proteínas/fisiologia , Supressão GenéticaRESUMO
Homeotic genes of Drosophila melanogaster encode transcription factors that specify segment identity by activating the appropriate set of target genes required to produce segment-specific characteristics. Advances in understanding target gene selection have been hampered by the lack of genes known to be directly regulated by the HOM-C proteins. Here we present evidence that the gene 1.28 is likely to be a direct target of Deformed in the maxillary segment. We identified a 664-bp Deformed Response Element (1.28 DRE) that directs maxillary-specific expression of a reporter gene in transgenic embryos. The 1.28 DRE contains in vitro binding sites for Deformed and DEAF-1. The Deformed binding sites do not have the consensus sequence for cooperative binding with the cofactor Extradenticle, and we do not detect cooperative binding to these sites, though we cannot rule out an independent role for Extradenticle. Removing the four Deformed binding sites renders the 1.28 DRE inactive in vivo, demonstrating that these sites are necessary for activation of this enhancer element, and supporting the proposition that 1.28 is activated by Deformed. We show that the DEAF-1 binding region is not required for enhancer function. Comparisons of the 1.28 DRE with other known Deformed-responsive enhancers indicate that there are multiple ways to construct Deformed Response Elements.
Assuntos
Drosophila melanogaster/genética , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica , Genes Homeobox , Animais , Animais Geneticamente Modificados , Sequência de Bases , Sítios de Ligação , Drosophila melanogaster/embriologia , Embrião não Mamífero/fisiologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Homologia de Sequência do Ácido NucleicoRESUMO
The homeotic selector genes of Drosophila melanogaster encode transcriptional regulatory proteins that control the determination of different segmental fates. Binding of selector proteins to regulatory DNA sequences is mediated by an evolutionary conserved protein domain, the homeodomain. Although homeodomains encoded by the selector genes are very similar in their amino acid sequence and in vitro DNA-binding properties, here we provide additional evidence that the homeodomain is responsible for most of the regulatory specificity of the entire protein. A heat-shock promoter/selector gene was constructed that encodes a Deformed/Abdominal-B chimera in which the Abdominal-B homeodomain is substituted for that of Deformed. Expression of this chimeric protein throughout the embryo causes morphological transformation of anterior segments toward more posterior identities. A number of other homeotic selector genes, all normally repressed by Abdominal-B, are ectopically activated by the chimeric protein. These results support the hypothesis that the target specificity of similar homeodomain proteins is largely determined by the amino acid sequence of the homeodomain.
Assuntos
Drosophila melanogaster/genética , Genes Homeobox , Fatores de Transcrição/genética , Abdome/embriologia , Animais , Animais Geneticamente Modificados , Sequência de Bases , Drosophila melanogaster/embriologia , Regulação da Expressão Gênica , Genes Dominantes , Genes Sintéticos , Proteínas de Choque Térmico/genética , Larva , Dados de Sequência Molecular , Morfogênese/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/fisiologia , Fatores de Transcrição/fisiologia , Transcrição GênicaRESUMO
The homeobrain (hbn) gene is a new paired-like homeobox gene which is expressed in the embryonic brain and the ventral nerve cord. Expression of homeobrain initiates during the blastoderm stage in the anterior dorsal head primordia and the gene is persistently expressed in these cells which form parts of the brain during later embryonic stages. An additional weaker expression pattern is detected in cells of the ventral nerve cord from stage 11 on. The homeodomain in the Homeobrain protein is most similar to the Drosophila proteins DRx, Aristaless and Munster. In addition, the localized brain expression patterns of homeobrain and DRx resemble each other. Two other homeobox genes, orthopedia and DRx are clustered in the 57B region along with homeobrain. The current evidence indicates that homeobrain, DRx and orthopedia form a homeobox gene cluster in which all the members are expressed in specific embryonic brain subregions.
Assuntos
Encéfalo/embriologia , Proteínas de Drosophila , Drosophila/embriologia , Proteínas de Homeodomínio/biossíntese , Fatores de Transcrição , Sequência de Aminoácidos , Animais , Expressão Gênica , Genes Homeobox , Proteínas de Homeodomínio/genética , Hibridização In Situ , Proteínas de Insetos/biossíntese , Modelos Genéticos , Dados de Sequência Molecular , Filogenia , Fatores de TempoRESUMO
The Drosophila paired (prd) gene, the founding member of the PAX gene family, is required for normal embryonic segmentation and is re-expressed later in development in the head and developing CNS. As for most embryonically active genes, global defects resulting from loss of early prd function obscure an analysis of the role of later expression phases. We used inducible targeted ribozymes to functionally 'knock-out' prd at late stages. When prd protein levels in the head are reduced in this fashion, the maxillary chemosensory ventral organs fail to develop and dorsal-lateral cirri rows are disrupted. These studies reveal a role for prd in sensory organ development that appears to be conserved in PAX genes throughout the animal kingdom.
Assuntos
Drosophila/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Genes de Insetos , Genes Reguladores , RNA Catalítico/metabolismo , Órgãos dos Sentidos/embriologia , Animais , Sequência de Bases , Drosophila/embriologia , Dados de Sequência MolecularRESUMO
Mammalian genomes contain clusters of homeobox genes (Hox-C, HOX-C) which are structurally similar to the homeotic genes of the Drosophila HOM complex. One method for assessing the functional similarity of particular Drosophila HOM and mammalian Hox genes is to test the ability of Hox genes to induce homeotic phenotypes when expressed in developing Drosophila. Here we describe such functional tests using mouse HoxB9 (formerly Hox-2.5), whose closest structural relative in Drosophila is Abdominal-B. When expressed from a heat shock promoter, HoxB9 induces transformations of head towards more posterior identities in Drosophila larvae and adults. These transformations share some similarities with the phenotypic effects produced by ectopically expressed Abdominal-B, but are also similar to the transformations induced by Antennapedia and mouse HoxB6 (Hox-2.2), suggesting that HoxB9 specifies a positional identity that is intermediate between Antennapedia and Abdominal-B.
Assuntos
Drosophila/genética , Genes Homeobox , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/química , Drosophila/crescimento & desenvolvimento , Proteínas de Choque Térmico/genética , Proteínas de Homeodomínio/química , Larva/genética , Camundongos , Dados de Sequência Molecular , Fenótipo , Proteínas , Transformação GenéticaRESUMO
Per protocol, patients with primary CNS non-Hodgkin's lymphoma in an intergroup phase II trial conducted by the North Central Cancer Treatment Group and the Eastern Cooperative Oncology Group had their cognitive functions measured using the Folstein and Folstein Mini-Mental Status Examination (MMSE) and their physical functions measured using the Eastern Cooperative Oncology Group Performance Score (PS) at study entry, at each treatment evaluation, and at quarterly intervals thereafter until disease progression or death. Of the 53 eligible participants who began therapy, 46 (87%) had baseline MMSE scores recorded, 36 (68%) had at least one follow-up MMSE, and 32 (60%) had both, while 52 (98%) had baseline PS, 49 (92%) had at least one follow-up PS, and 48 (91%) had both. Patterns of MMSE and PS values over time were studied in each individual, in the group as a whole, in the 20 patients who completed the study regimen, in the 23 who survived more than a year, and in patients who were classified as nonprogressors at each key evaluation. For each patient, all recorded values were plotted versus time, with dates of disease progression and death included, to look for signs of decline in cognitive or physical function preceding adverse events. Long-term declines in scores of both cognitive and physical function were observed in many treated patients with primary CNS non-Hodgkin's lymphoma. Nearly all patients who were alive more than 52 weeks after study entry had a demonstrable decline in cognitive and physical functionality. Such declines may occur before disease progression is documented; they may also occur in some patients who have long-term follow-up without evidence of disease progression. Declining MMSE and PS was a poor predictor of disease progression. There was no association of PS and toxicity. The data from this study demonstrated the considerable difficulties we encountered conducting an ancillary study such as this within a multicenter clinical trial. Firstly, the test instruments written into the protocol were unable to tell if the declines seen were due to disease, treatment, co-morbidity, or other factors. Secondly, the missing data created difficulties in interpreting outcome.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Sistema Nervoso Central/complicações , Transtornos Cognitivos/etiologia , Irradiação Craniana/efeitos adversos , Linfoma não Hodgkin/complicações , Radioterapia Adjuvante/efeitos adversos , Adulto , Fatores Etários , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Sistema Nervoso Central/psicologia , Neoplasias do Sistema Nervoso Central/terapia , Transtornos Cognitivos/epidemiologia , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Feminino , Seguimentos , Humanos , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/psicologia , Linfoma não Hodgkin/radioterapia , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Testes Psicológicos , Desempenho Psicomotor , Lesões por Radiação/etiologia , Lesões por Radiação/psicologia , Índice de Gravidade de Doença , Resultado do Tratamento , Vincristina/administração & dosagem , Vincristina/efeitos adversosRESUMO
PURPOSE: We herein report updated survival and toxicity data on the entire cohort of 53 eligible patients treated on North Central Cancer Treatment Group (NCCTG) protocol 86-72-52, which is now closed. METHODS AND MATERIALS: An initial report was published in this journal in 1995. No substantive changes in the conclusions of that report were identified in this analysis. Median survival was 9.6 months for the entire cohort; median survival for the 20 patients who completed the prescribed protocol treatment was 20.7 months. The hematologic and non-hematologic toxicity distributions are virtually the same as those reported in the original paper. RESULTS: Results are given for the entire group and for subsets defined by age < or = 60 versus > 60 years, and < 70 versus > or = 70 years of age. CONCLUSIONS: No significant differences were observed in any of the outcome variables by age group. There was, however, a nonsignificant suggestion of poorer outcome in those who were > 60 years of age.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Neoplasias Encefálicas/mortalidade , Estudos de Coortes , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Linfoma não Hodgkin/mortalidade , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prognóstico , Recidiva , Vincristina/administração & dosagemRESUMO
The putative promoter region of the SNRPN gene contains a CpG island which is heavily methylated in the maternally derived allele and unmethylated in the paternally derived allele. In patients with Prader-Willi syndrome (PWS) only the methylated allele is present, while in those with Angelman syndrome (AS) only the unmethylated allele is present. The purpose of this paper is to report a polymerase chain reaction (PCR)-based assay to evaluate methylation status of the CpG island of the SNRPN gene and to show that this assay allows rapid diagnosis of PWS and AS. Methylated cytosines in the CpG dinucleotide are resistant to chemical modification by sodium bisulfite. In contrast, bisulfite treatment converts all unmethylated cytosines to uracil. Based on this differential effect, the bisulfite-modified DNA sequence of a methylated allele was successfully distinguished from that of an unmethylated allele using 2 sets of allele-specific primer pairs: a methylated allele-specific primer pair (MET) and an unmethylated allele-specific primer pair (UNMET). Bisulfite-modified DNA from 10 patients with PWS amplified only with the MET pair while modified DNA from 5 patients with AS amplified only with the UNMET pair. Modified DNA from 50 normal unrelated individuals amplified with both primer pairs. In that methylation-specific PCR (MSPCR) can detect all presently testable causes of PWS and AS in a rapid and cost-effective fashion, serious consideration should be given to the use of this test in the initial evaluation of all patients in which PWS or AS is being considered.
Assuntos
Síndrome de Angelman/genética , Metilação de DNA , Reação em Cadeia da Polimerase/métodos , Síndrome de Prader-Willi/genética , Sulfitos , Síndrome de Angelman/diagnóstico , Animais , Autoantígenos/genética , Sequência de Bases , Feto , Humanos , Dados de Sequência Molecular , Pan paniscus , Pan troglodytes , Síndrome de Prader-Willi/diagnóstico , Ribonucleoproteínas Nucleares Pequenas/genética , Proteínas Centrais de snRNPRESUMO
OBJECT: It is standard practice for the oncological follow-up of patients with brain tumors (especially in the setting of clinical trials) to include neurological examination and neuroradiological studies such as computerized tomography (CT) or magnetic resonance (MR) imaging in addition to evaluation of the patients' symptomatology and performance score. The validity of this practice and its impact on the welfare of patients with high-grade gliomas has not been adequately assessed. The purpose of this study is to provide such an assessment. METHODS: The authors studied 231 similarly treated patients who were participating in three prospective North Central Cancer Treatment Group or Mayo Clinic trials who developed progressive disease during follow up. According to the protocol, the symptom status, performance score, results of neurological examination, and CT or MR status were recorded prospectively in each patient at each evaluation (every 6-8 weeks). At progression, 177 (77%) of 231 patients experienced worsening of their baseline symptoms or they developed new ones. In the remaining 54 asymptomatic patients (23%), neuroradiological imaging revealed the progression. Asymptomatic progression was more likely to be detected on MR imaging compared with CT studies (p < 0.01). In no asymptomatic patient was progression detected on neurological examination alone. The median survival time after tumor recurrence was 13.3 weeks in symptomatic patients compared with 41.7 weeks in the asymptomatic group (p < 0.0001). Asymptomatic patients were more aggressively treated, with surgery (p < 0.0001) and second-line chemotherapy (p < 0.0002). Multivariate analysis of survival time following first progression by using both classification and regression trees and Cox models showed that treatment at recurrence was the most important prognostic variable. CONCLUSIONS: Symptoms are the most frequent indicators of progression in patients with high-grade gliomas (77%). All asymptomatic progressions were detected on neuroradiological studies; MR imaging was more likely than CT scanning to reveal asymptomatic recurrences. Survival after disease progression was significantly longer in asymptomatic patients and could be related both to treatment following progression and to other favorable prognostic factors such as performance score.