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3.
Br J Dermatol ; 170(3): 699-704, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24024659

RESUMO

BACKGROUND: Topical nitrogen mustard is a widely used therapy in patients with mycosis fungoides (MF). However, it remains controversial whether nitrogen mustard therapy is associated with increased risk of secondary cancers and chronic pulmonary diseases in patients with MF. OBJECTIVES: To assess the risk of secondary cancers, comorbidities, mortality and cause-specific mortality in patients with MF treated with nitrogen mustard compared with patients not receiving this treatment. METHODS: Linking the Danish nationwide registries in a 30-year population-based cohort study, we compared 110 patients with MF from a regional Danish centre using nitrogen mustard treatment with 193 patients from Danish centres not using nitrogen mustard. The two cohorts were compared by Cox regression analysis. RESULTS: Overall, secondary cancers were not significantly increased [hazard ratio (HR) 0.84, 95% confidence interval (CI) 0.46-1.56], and subanalyses showed no significantly increased risk of nonmelanoma skin cancers, malignant melanomas or cancers in the respiratory organs in the nitrogen mustard-treated cohort. Furthermore, we found no significantly increased risk of any category of comorbidity, including chronic pulmonary diseases, in patients treated with nitrogen mustard (HR 0.93, 95% CI 0.48-1.81). Moreover, mortality and cause-specific mortality did not significantly differ between the two cohorts. CONCLUSIONS: This study does not support any previous suspicion of increased risk of secondary cancers and chronic pulmonary diseases among patients with MF treated with nitrogen mustard. Furthermore, mortality and cause-specific mortality were not influenced by nitrogen mustard treatment. Thus our findings indicate that topical nitrogen mustard is a safe therapy in patients with MF.


Assuntos
Antineoplásicos Alquilantes/efeitos adversos , Mecloretamina/efeitos adversos , Micose Fungoide/tratamento farmacológico , Segunda Neoplasia Primária/induzido quimicamente , Neoplasias Cutâneas/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Estudos de Coortes , Dinamarca/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Micose Fungoide/mortalidade , Segunda Neoplasia Primária/mortalidade , Fatores de Risco , Neoplasias Cutâneas/mortalidade , Adulto Jovem
4.
J Eur Acad Dermatol Venereol ; 27(2): 163-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22229501

RESUMO

BACKGROUND: Topical nitrogen mustard is a chemotherapeutic agent used in treatment of mycosis fungoides (MF). OBJECTIVE: To evaluate the response and side effects in patients with MF and parapsoriasis treated with topical nitrogen mustard. METHODS: A retrospective study of treatment response in 116 patients diagnosed with MF and 71 patients with parapsoriasis and treated with topical nitrogen mustard from 1991 to 2009. RESULTS: Overall response rate and complete response (CR) rate was 91.4% and 53.4% in patients with MF and 90.1% and 40.8% in patients with parapsoriasis, respectively. Relapse following CR was observed in 67.7% in patients with MF and 62.1% in patients with parapsoriasis. Freedom-from-relapse was higher in patients with T1-T2 than in T3 disease (P < 0.01). Progressive disease (PD) occurred in 25.0% and 26.8% in patients with MF and parapsoriasis, respectively. Progression-free survival was similar in patients with T1-T2 compared with T3 (P = 0.79) and T4 disease (P = 0.22) and lower in patients with parapsoriasis with <10% than >10% skin involvement (P = 0.05). CONCLUSION: The present study confirms that topical nitrogen mustard is a safe and effective therapy. The treatment response in patients with parapsoriasis was not statistically different from the response in patients with MF. This supports, that parapsoriasis is not a distinct entity, but an early stage of MF. Nitrogen mustard should therefore still be considered as an important treatment modality in patients with early stages (parapsoriasis) and later stages of MF either as monotherapy or in combination with other topical or systemic therapies.


Assuntos
Mecloretamina/uso terapêutico , Micose Fungoide/tratamento farmacológico , Parapsoríase/tratamento farmacológico , Administração Tópica , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Humanos , Masculino , Mecloretamina/administração & dosagem , Mecloretamina/efeitos adversos , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
5.
J Neuroendocrinol ; 24(6): 930-43, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22295972

RESUMO

Interleukin (IL)-6 deficient mice develop mature-onset obesity. Furthermore, i.c.v. administration of IL-6 increases energy expenditure, suggesting that IL-6 centrally regulates energy homeostasis. To investigate whether it would be possible for IL-6 to directly influence the energy homeostasis via hypothalamic regulation in humans and rodents, we mapped the distribution of the ligand binding IL-6 receptor α (IL-6Rα) in this brain region. In the human hypothalamus, IL-6Rα-immunoreactivity was detected in perikarya and first-order dendrites of neurones. The IL-6Rα-immunoreactive (-IR) neurones were observed posterior to the level of the interventricular foramen. There, IL-6Rα-IR neurones were located in the lateral hypothalamic, perifornical, dorsal and posterior hypothalamic areas, the hypothalamic dorsomedial nucleus and in the zona incerta. In the caudal part of the hypothalamus, the density of the IL-6Rα-IR neurones gradually increased. Double-labelling immunofluorescent studies demonstrated that IL-6Rα immunoreactivity was localised in the same neurones as the orexigenic neuropeptide, melanin-concentrating hormone (MCH). By contrast, IL-6Rα-immunoreactivity was not observed in the orexin B-IR neurones. To determine whether the observed expression of IL-6Rα is evolutionary conserved, we studied the co-localisation of IL-6Rα with MCH and orexin in the mouse hypothalamus, where IL-6Rα-immunoreactivity was present in numerous MCH-IR and orexin-IR neurones. Our data demonstrate that the MCH neurones of the human hypothalamus, as well as the MCH and orexin neurones of the mouse hypothalamus, contain IL-6Rα. This opens up the possibility that IL-6 influences the energy balance through the MCH neurones in humans, and both MCH and orexin neurones in mice.


Assuntos
Hormônios Hipotalâmicos/metabolismo , Hipotálamo/metabolismo , Melaninas/metabolismo , Hormônios Hipofisários/metabolismo , Receptores de Interleucina-6/metabolismo , Adulto , Animais , Humanos , Hormônios Hipotalâmicos/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Melaninas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Neuropeptídeos/metabolismo , Orexinas , Hormônios Hipofisários/fisiologia
6.
Br J Dermatol ; 166(2): 399-404, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21967035

RESUMO

BACKGROUND: Total skin electron beam therapy (TSEBT) is a powerful treatment for cutaneous T-cell lymphoma (CTCL). Based on the occurrence of relapses with low radiation doses, doses of 30-36Gy are commonly used but most patients still eventually relapse and repeat treatment courses are limited due to the cumulative toxicity. Complete response (CR) rates are about 60-90% for T2-4 stages with a 5-year relapse-free survival of 10-25% for stages IB-III. OBJECTIVES: To evaluate prospectively the efficacy of low-dose TSEBT (10Gy) in terms of complete cutaneous response rate, overall response rate and response duration in CTCL. METHODS: Ten patients with stage IB-IV mycosis fungoides (MF) were treated in an open-label manner with four fractions of TSEBT 1Gy weekly to a total skin dose of 10Gy. Treatment responses were assessed at 1 and 3months after treatment and subsequently at least every 6months for a total period of 2years or to disease relapse or progression. RESULTS: Patients achieved an overall response rate of 90%. The rate of CR or very good partial response (VGPR; <1% skin affected with patches/plaques) was 70%. The median response duration was 5·2months (range 83-469days) for CR and VGPR. Adverse effects were generally mild to moderate in severity. CONCLUSIONS: Low-dose TSEBT (10Gy) gave a satisfactory response rate and was well tolerated in patients with MF stage IB-IV. Future studies should determine if the combination of low-dose TSEBT with other agents could increase the rate of CR and response duration.


Assuntos
Elétrons/uso terapêutico , Micose Fungoide/radioterapia , Neoplasias Cutâneas/radioterapia , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Relação Dose-Resposta à Radiação , Elétrons/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
7.
Br J Dermatol ; 166(3): 642-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21967132

RESUMO

BACKGROUND: Langerhans cell histiocytosis (LCH) is characterized by abnormal proliferation and infiltration of Langerhans cells in different organs. The skin is frequently involved either as unisystem or multisystem disease. OBJECTIVES: To review the clinical response and side-effects of nitrogen mustard therapy in LCH in children and adults with unisystem or multisystem disease. PATIENTS AND METHODS: This retrospective study includes 10 children and four adults with LCH, treated with nitrogen mustard from 1975 to 2010. The median extent of skin involvement was 46% (range 5-100%). RESULTS: Overall, 13 patients had complete or partial response. Although eight patients achieved a complete response with a median time of 12·3months (range 36 days to 1·9 years), six of these patients ultimately relapsed. One patient, who had unisystem disease limited to the skin, initially showed progression of her cutaneous lesions with nitrogen mustard treatment. Although subsequently the cutaneous lesions completely regressed, concomitant systemic involvement was noted. Four other patients similarly experienced improvement of their skin lesions with treatment, but also exhibited progression of the LCH systemically. The patients were treated with other therapies prior and adjunctive to nitrogen mustard. However, five patients had progression to other organs, despite regression of skin lesions, which supports that the treatment effect in the skin is related to topical nitrogen mustard. Six patients developed contact dermatitis to nitrogen mustard. CONCLUSIONS: Topical nitrogen mustard can be an effective and safe therapy in both children and adults with cutaneous LCH, although relapses are common.


Assuntos
Fármacos Dermatológicos/administração & dosagem , Histiocitose de Células de Langerhans/tratamento farmacológico , Mecloretamina/administração & dosagem , Dermatopatias/tratamento farmacológico , Administração Cutânea , Adolescente , Adulto , Criança , Pré-Escolar , Dermatite Irritante/etiologia , Fármacos Dermatológicos/efeitos adversos , Esquema de Medicação , Toxidermias/etiologia , Humanos , Lactente , Mecloretamina/efeitos adversos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
8.
J Neuroendocrinol ; 21(9): 777-85, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19703102

RESUMO

In the present study, we explore the central nervous system mechanism underlying the chronic central effects of ghrelin with respect to increasing body weight and body fat. Specifically, using a recently developed ghrelin receptor antagonist, GHS-R1A (JMV2959), we investigate the role of GHS-R1A in mediating the effects of ghrelin on energy balance and on hypothalamic gene expression. As expected, in adult male rats, chronic central treatment with ghrelin for 14 days, when compared to vehicle-treated control rats, resulted in an increased body weight, lean mass and fat mass (assessed by dual X-ray absorptiometry), dissected white fat pad weight, cumulative food intake, food efficiency, respiratory exchange ratio and a decrease of energy expenditure. Co-administration of the ghrelin receptor antagonist JMV2959 suppressed/blocked the majority of these effects, with the notable exception of ghrelin-induced food intake and food efficiency. The hypothesis emerging from these data, namely that GHS-R1A mediates the chronic effects of ghrelin on fat accumulation, at least partly independent of food intake, is discussed in light of the accompanying data regarding the hypothalamic genes coding for peptides and receptors involved in energy balance regulation, which were found to have altered expression in these studies.


Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Grelina/farmacologia , Antagonistas de Hormônios/farmacologia , Obesidade/induzido quimicamente , Receptores de Grelina/antagonistas & inibidores , Animais , Composição Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/fisiologia , Ingestão de Alimentos/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Grelina/administração & dosagem , Grelina/efeitos adversos , Grelina/antagonistas & inibidores , Hormônios/sangue , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Injeções Intraventriculares , Masculino , Obesidade/sangue , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
9.
J Neuroendocrinol ; 21(7): 620-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19490366

RESUMO

Interleukin (IL)-6 is a pro-inflammatory cytokine that also affects metabolic function because IL-6 depleted (IL-6(-/-)) mice develop late-onset obesity. IL-6 appears to act in the central nervous system, presumably in the hypothalamus, to increase energy expenditure that appears to involve stimulation of the sympathetic nervous system. In the present study, we explored possible central mechanisms for the effects exerted by IL-6 on body fat. Therefore, we measured the effects of IL-6 depletion in IL-6(-/-) mice on expression of key hypothalamic peptide genes involved in energy balance by the real time polymerase chain reaction. Additionally, co-localisation between such peptides and IL-6 receptor alpha was investigated by immunohistochemistry. IL-6 deficiency decreased the expression of several peptides found in the paraventricular nucleus (PVN), which is a nucleus that has been attributed an adipostatic function. For example, corticotrophin-releasing hormone (CRH), which is reported to stimulate the sympathetic nervous system, was decreased by 40% in older IL-6(-/-) mice. Oxytocin, which is reported to prevent obesity, was also decreased in older IL-6(-/-) animals, as was arginine vasopressin (AVP). The IL-6 receptor alpha was abundantly expressed in the PVN, but also in the supraoptic nucleus, and was shown to be co-expressed to a high extent with CRH, AVP, oxytocin and thyrotrophin-releasing hormone. These data indicate that depletion of endogenous IL-6, a body fat suppressing cytokine, is associated with the decreased expression of CRH and oxytocin (i.e. energy balance regulating peptides) as well as AVP in the PVN. Because IL-6 receptor alpha is co-expressed with CRH, oxytocin and AVP, IL-6 could stimulate the expression of these peptides directly.


Assuntos
Interleucina-6/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Núcleo Supraóptico/metabolismo , Adiposidade/genética , Adiposidade/fisiologia , Animais , Arginina Vasopressina/metabolismo , Contagem de Células , Hormônio Liberador da Corticotropina/metabolismo , Imuno-Histoquímica , Interleucina-6/deficiência , Interleucina-6/genética , Subunidade alfa de Receptor de Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ocitocina/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Hormônio Liberador de Tireotropina/metabolismo
10.
J Mol Endocrinol ; 29(1): 125-35, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12200234

RESUMO

Estrogens up-regulate expression of the estrogen receptor alpha (ER) gene in most mammalian tissues studied. Using the ovariectomized ewe as a model, we determined that estradiol (E(2)) acted post-transcriptionally to increase endometrial ER mRNA concentrations by enhancing the stability of the message. The purpose of this study was to determine whether a similar E(2) effect occurs in Ishikawa cells, a well-differentiated human endometrial adenocarcinoma cell line. The presence and function of ER protein in Ishikawa cells was demonstrated by transactivation of a transfected plasmid (ERE(2)tkCAT) in response to 10(-)(9) M E(2), resulting in a 550% increase in reporter gene RNA. Ishikawa cells also responded to E(2) by up-regulating their ER mRNA concentration an average of 100% between 7 and 24 h of treatment. The effect of E(2) on ER mRNA stability was measured after blocking transcription with actinomycin D to find that the half-life increased from 6 to 10 h in control and E(2)-treated cells respectively. These results are consistent with cell-free studies which showed significant enhancement of the half-life of radiolabeled ER 3' untranslated region (3'UTR) RNA in extracts from E(2)-treated cells versus those from control cells. Thus, Ishikawa cells provide a relevant model system for the study of E(2)-regulated endometrial gene expression.


Assuntos
Neoplasias do Endométrio/metabolismo , Estradiol/farmacologia , RNA Mensageiro/metabolismo , Receptores de Estrogênio/genética , Regulação para Cima/efeitos dos fármacos , Animais , Northern Blotting , Sistema Livre de Células , Dactinomicina/farmacologia , Neoplasias do Endométrio/patologia , Feminino , Regiões Promotoras Genéticas , Sondas RNA , Ovinos , Transcrição Gênica/efeitos dos fármacos , Células Tumorais Cultivadas
11.
RNA ; 6(5): 653-8, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10836786

RESUMO

RNase MRP and RNase P are both ribonucleoprotein enzymes performing endonucleolytic cleavage of RNA. RNase MRP cleaves at a specific site in the precursor-rRNA transcript to initiate processing of the 5.8S rRNA. RNase P cleaves precursor tRNAs to create the 5' end of the mature tRNAs. In spite of their different specificities, the two RNases have significant structural similarities. For example, the two enzymes in Saccharomyces cerevisiae share eight protein subunits; only one protein is unique to each enzyme. The RNA components of the two nucleases also show striking secondary-structure similarity. To begin to characterize the role of the RNA subunits in enzyme function and substrate specificity, we swapped two hairpin structures (MRP3 and P3) between RNase MRP RNA and RNase P RNA of S. cerevisiae. The hairpins in the two enzymes could be exchanged without loss of function or specificity. On the other hand, when the MRP3 hairpin in RNase MRP of S. cerevisiae was replaced with the corresponding hairpin from the RNA of Schizosaccharomyces pombe or human RNase MRP, no functional enzyme was assembled. We propose that the MRP3 and P3 hairpins in S. cerevisiae perform similar functions and have coevolved to maintain common features that are different from those of MRP3 and P3 hairpins in other species.


Assuntos
Endorribonucleases/química , Endorribonucleases/metabolismo , RNA Catalítico/química , RNA Catalítico/metabolismo , RNA Fúngico/química , RNA Fúngico/metabolismo , Ribonucleoproteínas/química , Ribonucleoproteínas/metabolismo , Saccharomyces cerevisiae/enzimologia , Sequência de Bases , Endorribonucleases/genética , Humanos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA Catalítico/genética , RNA Fúngico/genética , Ribonuclease P , Ribonucleoproteínas/genética , Saccharomyces cerevisiae/genética , Schizosaccharomyces/enzimologia , Schizosaccharomyces/genética , Especificidade da Espécie
13.
J Bacteriol ; 181(19): 6124-32, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10498727

RESUMO

We investigated the regulation of the S10 ribosomal protein (r-protein) operon among members of the gamma subdivision of the proteobacteria, which includes Escherichia coli. In E. coli, this 11-gene operon is autogenously controlled by r-protein L4. This regulation requires specific determinants within the untranslated leader of the mRNA. Secondary structure analysis of the S10 leaders of five enterobacteria (Salmonella typhimurium, Citrobacter freundii, Yersinia enterocolitica, Serratia marcescens, and Morganella morganii) and two nonenteric members of the gamma subdivision (Haemophilus influenzae and Vibrio cholerae) shows that these foreign leaders share significant structural homology with the E. coli leader, particularly in the region which is critical for L4-mediated autogenous control in E. coli. Moreover, these heterologous leaders produce a regulatory response to L4 oversynthesis in E. coli. Our results suggest that an E. coli-like L4-mediated regulatory mechanism may operate in all of these species. However, the mechanism is not universally conserved among the gamma subdivision members, since at least one, Pseudomonas aeruginosa, does not contain the required S10 leader features, and its leader cannot provide the signals for regulation by L4 in E. coli. We speculate that L4-mediated autogenous control developed during the evolution of the gamma branch of proteobacteria.


Assuntos
Regulação Bacteriana da Expressão Gênica , Bactérias Gram-Negativas/genética , Óperon , Sequências Reguladoras de Ácido Nucleico , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Sequência de Bases , Simulação por Computador , Escherichia coli/genética , Evolução Molecular , Genes Bacterianos , Modelos Moleculares , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Proteínas Ribossômicas/biossíntese , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
14.
Toxicol Sci ; 50(2): 236-43, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10478860

RESUMO

The apparent ability of astroglia to serve as a lead (Pb) sink in the mature brain may result from either their strategic location, between the blood-brain barrier and neurons, or from intrinsic differences between the ability of astroglia and neurons to accumulate this metal. This phenomenon may be dependent on the degree of cell differentiation. In order to address the latter possibility, Pb accumulation was compared among the following cell culture models: (1) mature and immature rat astroglia, (2) undifferentiated SY5Y human neuroblastoma cells and SY5Y cells differentiated with nerve growth factor, (3) immature rat astroglia grown in differently conditioned media, some of which induce partial differentiation, and (4) rat astroglia and SY5Y cells in co-culture. Astroglial cultures, prepared from 1-day-old rat cerebral hemispheres, were exposed to 1 microM Pb after either 14 (immature) or 21 (mature) days in culture. Pb content of the cells was measured by atomic absorption spectroscopy. Immature astroglia took up less Pb when glutathione (GSH) was added to the medium, suggesting that GSH may regulate Pb uptake in these cells. Undifferentiated neuroblastoma cells accumulated more Pb than did the differentiated ones. Astroglia accumulated up to 24 times more Pb than did neuronal cells. This ability was enhanced by exposure to conditioned medium from a neuroblastoma cell line, but not by endothelial cell-conditioned medium, although this medium induced the expression of a glutamate-activated Ca2+ response. Our findings are in agreement with in vivo studies, and thus validate the use of these cell-culture models for future studies on differential mechanisms of Pb uptake.


Assuntos
Astrócitos/metabolismo , Diferenciação Celular/fisiologia , Chumbo/farmacocinética , Neuroblastoma/metabolismo , Neurônios/metabolismo , Fatores Etários , Animais , Animais Recém-Nascidos , Encéfalo/metabolismo , Cálcio/metabolismo , Canais de Cálcio/fisiologia , Células Cultivadas , Ácido Glutâmico/farmacologia , Glutationa/farmacologia , Humanos , Fator de Crescimento Neural/farmacologia , Ratos , Ratos Sprague-Dawley , Espectrofotometria Atômica , Células Tumorais Cultivadas
15.
J Bacteriol ; 179(22): 7046-54, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9371452

RESUMO

We have sequenced a previously uncharacterized region of the Bacillus subtilis S10 ribosomal protein gene cluster. The new segment includes genes for S10, L3, L4, L23, L2, S19, L22, S3, and part of L16. These B. subtilis genes map in the same order as the genes in the Escherichia coli S10 ribosomal protein operon. Two potential promoter sequences were identified, one approximately 200 bases and the other approximately 140 bases upstream of the S10 gene. The activities of the two promoters were demonstrated by primer extension analysis, in vitro transcription experiments, and in vivo promoter fusion plasmid studies. In agreement with previous reports, our Northern analysis of exponentially growing cells failed to identify terminators or other active promoters within the S10-spc-alpha region. Our observations suggest that the two S10 promoters reported here are responsible for transcribing a 15-kb-long transcript for all of the genes in the B. subtilis S10, spc, and alpha clusters.


Assuntos
Bacillus subtilis/genética , Regulação Bacteriana da Expressão Gênica , Regiões Promotoras Genéticas , RNA Ribossômico/genética , Sequência de Aminoácidos , Fusão Gênica Artificial , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , Escherichia coli/genética , Óperon Lac , Dados de Sequência Molecular , Estrutura Molecular , Família Multigênica , Óperon , Plasmídeos/genética , Reação em Cadeia da Polimerase , Sinais Direcionadores de Proteínas/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Ribossômico/química , Transcrição Gênica
16.
RNA ; 3(4): 382-91, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9085845

RESUMO

We have isolated suppressors of the temperature-sensitive rRNA processing mutation rrp2-2 in Saccharomyces cerevisiae. A class of extragenic suppressors was mapped to the YBR257w reading frame in the right arm of Chromosome II. Characterization of this gene, renamed POP4, shows that the gene product is necessary both for normal 5.8S rRNA processing and for processing of tRNA. Immunoprecipitation studies indicate that Pop4p is associated with both RNase MRP and RNase P. The protein is also required for accumulation of RNA from each of the two ribonucleoprotein particles.


Assuntos
Endorribonucleases/genética , Processamento Pós-Transcricional do RNA , RNA Catalítico/genética , Ribonucleoproteínas/genética , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Sequência de Bases , Dados de Sequência Molecular , RNA Ribossômico 5,8S/biossíntese , RNA de Transferência/biossíntese , Ribonuclease P , Saccharomyces cerevisiae/enzimologia
17.
Int J Oral Maxillofac Surg ; 25(2): 107-11, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8727580

RESUMO

Open reduction of dislocated subcondylar fractures was carried out in 19 adult patients between 1990 and 1992. A comparison of the results between two groups of patients was made 1 year after trauma. The reference group consisted of patients with the same type of fracture but treated with only intermaxillary fixation (IMF) and moderate jaw exercises after release of IMF. Dysfunction of the masticatory system was noticed in only a few cases of either group. Open reduction with plate osteosynthesis made it possible to avoid IMF in 12 of 19 patients. The results in the two groups did not differ significantly from a functional point of view. There are, however, specific indications for open reduction based on the degree of dislocation and concomitant subjective symptoms.


Assuntos
Fixação Interna de Fraturas/métodos , Côndilo Mandibular/lesões , Fraturas Mandibulares/reabilitação , Fraturas Mandibulares/cirurgia , Adolescente , Adulto , Idoso , Placas Ósseas , Criança , Feminino , Humanos , Imobilização , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
18.
J Bacteriol ; 178(8): 2383-7, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8636042

RESUMO

Ribosomal protein L4 of Escherichia coli regulates transcription of the 11-gene S1O operon by promoting premature termination of transcription (attenuation) at a specific site within the 172-base untranslated leader. We have analyzed the roles of various domains of the leader RNA in this transcription control. Our results indicate that the first 60 bases of the leader, forming the three proximal hairpin structures, are not essential for in vivo L4-mediated attenuation control. However, a deletion removing the fourth hairpin, which is immediately upstream of the terminator hairpin, eliminates L4's effect on transcription. Base changes disrupting complementarity in the 6-bp stem of this hairpin also abolish L4 control, but compensatory base changes that restore complementarity also restore L4's effect. In vitro transcription studies confirm that this hairpin structure is necessary for L4's role in stimulating transcription termination by RNA polymerase.


Assuntos
Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Conformação de Ácido Nucleico , Óperon , Proteínas Ribossômicas/metabolismo , Sequência de Bases , Análise Mutacional de DNA , Dados de Sequência Molecular , Deleção de Sequência , Regiões Terminadoras Genéticas , Transcrição Gênica
19.
RNA ; 2(1): 24-37, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8846294

RESUMO

Escherichia coli ribosomal protein L4 has two functions: it is a structural component of the 50S ribosomal sub-unit and it is a repressor of both transcription and translation of its own transcription unit, the 11-gene S10 operon. Genetic and biochemical studies have suggested that L4 can interact with 23S rRNA as well as with both RNA interactions. However, no significant similarities between its two RNA targets can be found at the primary or secondary structure level. To test if identical determinants of L4 are involved in both ribosome assembly and autogenous control, we have isolated L4 mutants defective in either of these functions and asked if a mutant protein divested of one function is also deficient in the other. Several mutations eliminated autogenous control, but still allowed assembly of the mutant L4 protein into functional ribosomes. Conversely, several mutant L4 proteins that could not be detected in 50S subunits nevertheless could regulate expression of the S10 operon. These results indicate that the L4 determinants required for autogenous regulation and ribosome incorporation are not congruent.


Assuntos
Escherichia coli/metabolismo , RNA Mensageiro/metabolismo , RNA Ribossômico 23S/metabolismo , Proteínas Ribossômicas/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Escherichia coli/genética , Deleção de Genes , Dados de Sequência Molecular , Proteínas Ribossômicas/genética , Alinhamento de Sequência
20.
Ann Nutr Metab ; 40(4): 212-20, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8886249

RESUMO

The changes in plasma insulin, enterostatin, lipid, and glucose levels during weight reduction were studied in 32 subjects having a body mass index of 25-35. The 31 subjects who completed the study followed for 23 weeks an energy-restricted dietary regimen which included a new oat-based soup as the main meal once or twice daily. The intake of energy decreased from 8.9 to 6.2 MJ/day from 0 to 22 weeks, the energy percentage from fat decreased from 35 to 30%, and the intake of dietary fiber increased from 21 to 25 g/10 MJ. The body weight decreased from 83 to 78 kg after 6 weeks and to 77 kg after 23 weeks. Plasma glucose had decreased significantly from 5.4 to 5.2 mmol/l, and plasma insulin from 122 to 98 pmol/l after 23 weeks. In contrast, the plasma enterostatin concentration did not vary significantly over five sampling times, the mean values ranging from 25 to 30 nmol/l. Plasma cholesterol declined from 5.6 to 5.2 mmol/l, low-density lipoprotein cholesterol from 3.8 to 3.3, and plasma triglycerides from 1.5 to 1.3 mmol/l from 0 to 23 weeks. High-density lipoprotein cholesterol increased from 1.1 to 1.3 mmol/l. It is concluded that an energy-restricted regimen leading to lower plasma insulin, triglyceride, and low-density lipoprotein cholesterol levels did not significantly affect the plasma enterostatin concentration in overweight subjects. A new oat-based liquid food as a part of the dietary regimen was well tolerated.


Assuntos
Colipases/sangue , Dieta , Alimentos Formulados , Insulina/sangue , Lipoproteínas/sangue , Precursores de Proteínas/sangue , Adulto , Avena , Glicemia/metabolismo , Índice de Massa Corporal , Peso Corporal/fisiologia , Metabolismo Energético/fisiologia , Precursores Enzimáticos , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Obesidade/dietoterapia
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