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1.
J Eur Acad Dermatol Venereol ; 38(1): 31-41, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37818828

RESUMO

Treating atopic dermatitis (AD) in pregnant or breastfeeding women, and in women and men with AD aspiring to be parents is difficult and characterized by uncertainty, as evidence to inform decision-making on systemic anti-inflammatory treatment is limited. This project mapped consensus across dermatologists, obstetricians and patients in Northwestern Europe to build practical advice for managing AD with systemic anti-inflammatory treatment in men and women of reproductive age. Twenty-one individuals (sixteen dermatologists, two obstetricians and three patients) participated in a two-round Delphi process. Full consensus was reached on 32 statements, partial consensus on four statements and no consensus on four statements. Cyclosporine A was the first-choice long-term systemic AD treatment for women preconception, during pregnancy and when breastfeeding, with short-course prednisolone for flare management. No consensus was reached on second-choice systemics preconception or during pregnancy, although during breastfeeding dupilumab and azathioprine were deemed suitable. It may be appropriate to discuss continuing an existing systemic AD medication with a woman if it provides good disease control and its benefits in pregnancy outweigh its risks. Janus kinase (JAK) inhibitors, methotrexate and mycophenolate mofetil should be avoided by women during preconception, pregnancy and breastfeeding, with medication-specific washout periods advised. For men preconception: cyclosporine A, azathioprine, dupilumab and corticosteroids are appropriate; a 3-month washout prior to conception is desirable for methotrexate and mycophenolate mofetil; there was no consensus on JAK inhibitors. Patient and clinician education on appropriate (and inappropriate) AD treatments for use in pregnancy is vital. A shared-care framework for interdisciplinary management of AD patients is advocated and outlined. This consensus provides interdisciplinary clinical guidance to clinicians who care for patients with AD before, during and after pregnancy. While systemic AD medications are used uncommonly in this patient group, considerations in this article may help patients with severe refractory AD.


Assuntos
Ciclosporina , Dermatite Atópica , Gravidez , Masculino , Humanos , Feminino , Ciclosporina/uso terapêutico , Metotrexato/uso terapêutico , Aleitamento Materno , Dermatite Atópica/tratamento farmacológico , Azatioprina/uso terapêutico , Ácido Micofenólico/uso terapêutico , Consenso , Anti-Inflamatórios/uso terapêutico
2.
Science ; 248(4963): 1646-50, 1990 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-2194289

RESUMO

Transcription factor IID (TFIID) binds to the TATA box promoter element and regulates the expression of most eukaryotic genes transcribed by RNA polymerase II. Complementary DNA (cDNA) encoding a human TFIID protein has been cloned. The human TFIID polypeptide has 339 amino acids and a molecular size of 37,745 daltons. The carboxyl-terminal 181 amino acids of the human TFIID protein shares 80% identity with the TFIID protein from Saccharomyces cerevisiae. The amino terminus contains an unusual repeat of 38 consecutive glutamine residues and an X-Thr-Pro repeat. Expression of DNA in reticulocyte lysates or in Escherichia coli yielded a protein that was competent for both DNA binding and transcription activation.


Assuntos
Regiões Promotoras Genéticas , Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , Transcrição Gênica , Sequência de Aminoácidos , Clonagem Molecular , Escherichia coli/genética , Expressão Gênica , Células HeLa/metabolismo , Humanos , Dados de Sequência Molecular , Proteínas Recombinantes/metabolismo , Reticulócitos/metabolismo , Homologia de Sequência do Ácido Nucleico , Fator de Transcrição TFIID , Fatores de Transcrição/metabolismo
3.
Mol Cell Biol ; 13(6): 3650-9, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8497275

RESUMO

The TATA-binding protein (TBP) is an essential component of the transcriptional machinery of all three nuclear RNA polymerase enzymes. Comparison of the amino acid sequence of TBPs from a number of species reveals a highly conserved 180-residue C-terminal domain. In contrast, the N terminus is variable in both size and amino acid sequence. Overexpression of a TBP protein with a deletion of the nonconserved N terminus (TBP delta 57) in Saccharomyces cerevisiae results in a dominant negative phenotype of extremely slow growth. Associated with the slow-growth phenotype are defects in RNA polymerase II transcription in vivo. We have screened a high-copy-number yeast genomic library for suppression of the slow-growth phenotype and have isolated plasmids which encode suppressors of TBP delta 57 overexpression. Here we report the sequence and initial characterization of one suppressor, designated STD1 for suppressor of TBP deletion. The STD1 gene contains a single continuous open reading frame with the potential to encode a 50.2-kDa protein. Disruption of the STD1 gene indicates that it is not essential for vegetative growth, mating, or sporulation. High-copy-number suppression by the STD1 gene is not the result of a decrease in TBP delta 57 protein accumulation or DNA-binding activity; instead, STD1 suppression is coincident with the elimination of TBP delta 57-induced RNA polymerase II defects in both uninduced and induced transcription in vivo.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/genética , Genes Fúngicos , Genes Supressores , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , TATA Box , Fatores de Transcrição/genética , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Western Blotting , DNA Fúngico/genética , DNA Fúngico/isolamento & purificação , Proteínas de Ligação a DNA/metabolismo , Proteínas Fúngicas/metabolismo , Genes Dominantes , Biblioteca Genômica , Peptídeos e Proteínas de Sinalização Intracelular , Dados de Sequência Molecular , Mutação , RNA Fúngico/genética , RNA Fúngico/isolamento & purificação , Mapeamento por Restrição , Saccharomyces cerevisiae/metabolismo , Homologia de Sequência de Aminoácidos , Proteína de Ligação a TATA-Box , Fatores de Transcrição/metabolismo , Transcrição Gênica
4.
Mol Cell Biol ; 16(10): 5393-9, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8816451

RESUMO

Latency-active promoter 2 (LAP 2) is a TATA-less promoter in herpes simplex virus type 1 (HSV-1) that can express genes during viral latency. Four regions of LAP2 are protected from DNase I digestion in vitro by either HeLa cell nuclear extracts or purified Sp1. Transient gene expression assays of LAP2 substitution mutants demonstrate that two of the regions protected by Sp1 and three other regions protected by nuclear extract are important for promoter function. The mutation causing the most significant reduction in expression alters a stretch of 23 thymidine residues (T23) that binds a protein with several properties common to high-mobility-group (HMG) proteins. The T23 binding activity is heat stable, can be inhibited by poly(dA-dT).poly(dA-dT), and is inhibited by minor-groove-binding drugs. Antiserum directed against HMG I(Y) blocked the formation of one of the DNA-protein complexes on the T23 oligonucleotide, suggesting that a protein antigenically related to HMG I(Y) binds to LAP2 in vitro. Direct evidence of HMG I(Y) involvement in LAP2 function is provided by the findings that recombinant HMG I(Y) protein facilitates Sp1 binding to LAP2 in mobility shift assays and that antisense HMG I(Y) RNA specifically inhibits LAP2 function in vivo. These results suggest that DNA structure may be an important determinant of the activity of a promoter that is capable of escaping the global shutoff of transcription that occurs during viral latency.


Assuntos
Herpesvirus Humano 1/genética , Proteínas de Grupo de Alta Mobilidade/metabolismo , Regiões Promotoras Genéticas , Transcrição Gênica , Animais , Sequência de Bases , Núcleo Celular/metabolismo , Cloranfenicol O-Acetiltransferase/biossíntese , Chlorocebus aethiops , Pegada de DNA , Primers do DNA , DNA Viral/química , Desoxirribonuclease I , Genes Reporter , Células HeLa , Herpesvirus Humano 1/metabolismo , Humanos , Dados de Sequência Molecular , Mutagênese , Homologia de Sequência do Ácido Nucleico , Fator de Transcrição Sp1/metabolismo , Transfecção , Células Vero
5.
Mol Cell Biol ; 9(8): 3299-307, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2677669

RESUMO

We have studied the interactions of the Sp1 and IID transcription factors with a simple RNA polymerase II promoter. The adenovirus E1B core promoter consists essentially of a GC box and a TATA box, binding sites for the Sp1 and IID transcription factors, respectively. The E1B promoter is accurately transcribed in vitro using a mammalian transcription system. Sp1 activates E1B transcription in vitro in reactions using IID factor isolated from either human or yeast cells. In DNase I footprinting studies, Sp1 bound rapidly to its recognition sequence even at 0 degrees C (t1/2 less than 1 min). In contrast, yeast IID bound more slowly (t1/2 approximately 6 min at 25 degrees C) and required thermal energy for stable binding to the TATA box sequence. Dissociation rates were measured by the addition of specific oligonucleotide competitors to preformed DNA-protein complexes. Sp1 dissociates rapidly (t1/2 less than 1 min) at 25 degrees C, while yeast IID dissociates with an estimated t1/2 of 1 h at 25 degrees C. Sp1 and yeast IID bound to the E1B promoter simultaneously but independently. The rates of binding and dissociation of these factors were not significantly affected by the presence of the other factor. Bound Sp1 factor did not alter or enhance the yeast IID footprint. Oligonucleotide challenge of in vitro transcription reactions indicated that Sp1 also did not enhance the binding of the human IID factor to the E1B promoter. Thus the Sp1 factor activates transcription of the E1B gene by a mechanism that does not enhance the DNA-binding activity of the IID factor. Sp1 factor activates E1B transcription by 5- to 10-fold in vitro. Under these in vitro transcription conditions, transcripts due to reinitiation from an individual promoter complex contribute only a small portion of the total yield of E1B transcripts. Thus Sp1 cannot activate transcription by increasing the rate of initiation events per complex. Instead it appears that Sp1 acts by increasing the number of productive transcription complexes formed in vitro.


Assuntos
Adenoviridae/genética , Proteínas de Ligação a DNA/fisiologia , Regiões Promotoras Genéticas , Fatores de Transcrição/fisiologia , Transcrição Gênica , Sequência de Bases , Proteínas de Ligação a DNA/metabolismo , Desoxirribonuclease I , Células HeLa/fisiologia , Humanos , Dados de Sequência Molecular , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologia , Fator de Transcrição Sp1 , Fator de Transcrição TFIID , Fatores de Transcrição/metabolismo
6.
Mol Cell Biol ; 11(1): 63-74, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1986253

RESUMO

Transcription factor IID from Saccharomyces cerevisiae (YIID) binds the TATA box element present in most RNA polymerase II promoters. In this work, partial proteolysis was used as a biochemical probe of YIID structure. YIID consists of a protease-sensitive amino terminus and a highly stable, protease-resistant carboxy-terminal core. The cleavage sites of the predominant chymotrypsin- and trypsin-derived fragments were mapped to amino acid residues 40 to 41 and 48 to 49, respectively, by amino-terminal peptide sequencing. Removal of the amino terminus resulted in a dramatic increase in the ability of YIID to form a stable complex with DNA during gel electrophoresis mobility shift assays and a two- to fourfold increase in DNA-binding affinity, as assayed by DNase I footprinting analysis. The carboxy-terminal 190-amino-acid core was competent for transcription in vitro and was similar in activity to native YIID. DNA containing a TATA element induced hypersensitive sites in the amino-terminal domain and stabilized the core domain to further proteolytic attack. Native YIID did not bind to a TATA box at 0 degrees C, whereas the carboxy-terminal DNA-binding domain did. These results suggest that YIID undergoes a conformational change upon binding to a TATA box. Southern blotting showed that the carboxy-terminal domain is highly conserved, while the amino-terminal domain diverged rapidly in evolution, even between closely related budding yeasts.


Assuntos
Proteínas de Ligação a DNA/ultraestrutura , Fatores de Transcrição/ultraestrutura , Sítios de Ligação , Proteínas Fúngicas/ultraestrutura , Expressão Gênica , Genes Fúngicos , Técnicas In Vitro , Estrutura Molecular , Mapeamento de Peptídeos , Regiões Promotoras Genéticas , Conformação Proteica , Proteínas Recombinantes , Sequências Reguladoras de Ácido Nucleico , Mapeamento por Restrição , Saccharomyces cerevisiae , Relação Estrutura-Atividade , Temperatura , Fator de Transcrição TFIID , Transcrição Gênica
7.
Mol Cell Biol ; 19(7): 4561-71, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10373505

RESUMO

The Std1 protein modulates the expression of glucose-regulated genes, but its exact molecular role in this process is unclear. A two-hybrid screen for Std1-interacting proteins identified the hydrophilic C-terminal domains of the glucose sensors, Snf3 and Rgt2. The homologue of Std1, Mth1, behaves differently from Std1 in this assay by interacting with Snf3 but not Rgt2. Genetic interactions between STD1, MTH1, SNF3, and RGT2 suggest that the glucose signaling is mediated, at least in part, through interactions of the products of these four genes. Mutations in MTH1 can suppress the raffinose growth defect of a snf3 mutant as well as the glucose fermentation defect present in cells lacking both glucose sensors (snf3 rgt2). Genetic suppression by mutations in MTH1 is likely to be due to the increased and unregulated expression of hexose transporter genes. In media lacking glucose or with low levels of glucose, the hexose transporter genes are subject to repression by a mechanism that requires the Std1 and Mth1 proteins. An additional mechanism for glucose sensing must exist since a strain lacking all four genes (snf3 rgt2 std1 mth1) is still able to regulate SUC2 gene expression in response to changes in glucose concentration. Finally, studies with green fluorescent protein fusions indicate that Std1 is localized to the cell periphery and the cell nucleus, supporting the idea that it may transduce signals from the plasma membrane to the nucleus.


Assuntos
Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Glucose/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Proteínas Adaptadoras de Transdução de Sinal , Clonagem Molecular , Proteínas Fúngicas/genética , Regulação Enzimológica da Expressão Gênica , Proteínas Facilitadoras de Transporte de Glucose , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Proteínas de Fluorescência Verde , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Luminescentes/metabolismo , Proteínas de Membrana/genética , Proteínas de Transporte de Monossacarídeos/genética , Mutagênese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/metabolismo , beta-Frutofuranosidase
8.
Biochim Biophys Acta ; 670(1): 9-16, 1981 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-7272333

RESUMO

We have examined the alpha-actinin-F-actin interaction by measuring the effect of highly purified alpha-actinin on bound nucleotide exchange in F-actin. Exchange was followed by measuring the release of actin-bound [14C]ADP in the presence of ATP using an ultrafiltration technique. Alpha-Actinin increases by about 60 to 70% the rate of release of F-actin bound nucleotide when incubated for 1 h in the presence of 1 mM ATP/1 mM MgCl2/0.05 mM CaCl2/0.5 mM dithioerythritol/100 mM KCI/20 mM Tris-acetate, pH 7.5, at 37 degrees C. The ability of alpha-actinin to enhance nucleotide exchange was maximal when alpha-actinin was added at a level near 10% of actin present by weight (molar ratio of 1 alpha-actinin to 49 actin monomers). The potentiating effect of alpha-actinin on the nucleotide exchange rate of F-actin was not highly related to the Mg2+: ATP ratio present in the incubation mixture. Alpha-actinin also increased the rate of bound nucleotide exchange of f-actin was present in a reconstituted actomyosin suspension. The results are consistent with th possibility that one alpha-actinin can affect the structure of multiple actin monomers present in an actin filament.


Assuntos
Actinina/farmacologia , Actinas/metabolismo , Difosfato de Adenosina/metabolismo , Proteínas Musculares/farmacologia , Actomiosina/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Bovinos , Fenômenos Químicos , Química , Relação Dose-Resposta a Droga , Cinética , Magnésio/farmacologia , Cloreto de Magnésio , Miosinas/farmacologia , Ligação Proteica/efeitos dos fármacos , Suínos
9.
J Mol Biol ; 195(4): 809-18, 1987 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-2821282

RESUMO

We have studied the factors that affect transcription termination in vitro at the tR2 terminator of bacteriophage lambda and at the T1 terminator of the Escherichia coli rrnB operon. Termination efficiency at both of these sites is enhanced by the E. coli nusA protein, giving final efficiencies of termination in vitro comparable to those estimated in vivo. Transcripts terminated in the presence of nusA protein are all released from the RNA polymerase complex, indicating that a complete termination reaction is involved, rather than simply induction of a long pause at the terminator. The termination factor activity of the nusA protein does not depend on the presence of rho protein and is not detectably enhanced by that factor. Thus, the nusA protein appears to play a pleiotropic role in E. coli transcription, serving as an antitermination factor, RNA polymerase subunit and true termination factor for some terminator sites.


Assuntos
Proteínas de Bactérias/genética , Genes Reguladores , Regiões Terminadoras Genéticas , Transcrição Gênica , Bacteriófago lambda/genética , DNA Viral , Escherichia coli/genética , Plasmídeos , Moldes Genéticos
10.
Genetics ; 150(1): 31-42, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9725828

RESUMO

The calcium-dependent protein phosphatase calcineurin plays an essential role in ion homeostasis in yeast. In this study, we identify a parallel ion stress response pathway that is independent of the calcineurin signaling pathway. Cells with null alleles in both STD1 and its homologue, MTH1, manifest numerous phenotypes observed in calcineurin mutants, including sodium, lithium, manganese, and hydroxyl ion sensitivity, as well as alpha factor toxicity. Furthermore, increased gene dosage of STD1 suppresses the ion stress phenotypes in calcineurin mutants and confers halotolerance in wild-type cells. However, Std1p functions in a calcineurin-independent ion stress response pathway, since a std1 mth1 mutant is FK506 sensitive under conditions of ion stress. Mutations in other genes known to regulate gene expression in response to changes in glucose concentration, including SNF3, RGT2, and SNF5, also affect cell growth under ion stress conditions. Gene expression studies indicate that the regulation of HAL1 and PMR2 expression is affected by STD1 gene dosage. Taken together, our data demonstrate that response to ion stress requires the participation of both calcineurin-dependent and -independent pathways.


Assuntos
Calcineurina/metabolismo , Estresse Oxidativo , Saccharomyces cerevisiae/metabolismo , Sódio/metabolismo , Adaptação Fisiológica/genética , Sequência de Bases , Primers do DNA , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Dosagem de Genes , Regulação Fúngica da Expressão Gênica , Glucose/metabolismo , Homeostase , Mutação , Fenótipo , Saccharomyces cerevisiae/fisiologia , Transdução de Sinais
11.
J Neuropathol Exp Neurol ; 58(1): 40-5, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10068312

RESUMO

Over the last years, distinct genetic lesions have been associated with individual tumor entities. Stereotactic biopsy has become an essential diagnostic tool in surgical neuro-oncology. In order to evaluate the potential of molecular analyses in stereotactic biopsies, we examined a series of 156 human brain tumors from patients undergoing stereotactic biopsy for molecular alterations typically seen in astrocytic gliomas and compared those results with a control group of 268 astrocytic tumors obtained at open surgery. Stereotactic biopsies of astrocytomas with borderline histopathological features between the WHO grades II and III showed a higher rate of allelic losses on chromosome 10 than those of the WHO grade II from open surgery (p = 0.011). Stereotactic biopsies of astrocytomas with borderline histopathological features between the WHO grades III and IV showed a higher rate of allelic losses on chromosome 10 than those of the WHO grade III from open surgery (p = 0.013). This indicates that stereotactic biopsies with features intermediate between grades are likely to correspond to the higher malignancy grade. Our data demonstrate that molecular genetic approaches can be successfully applied to stereotactic glioma biopsies. The difference in the distribution of malignancy associated genetic alterations between a stereotactic and openly resected group of gliomas indicates that histopathology may underestimate the malignant potential in some stereotactic specimens. We propose to further evaluate the molecular analysis of stereotactic glioma biopsies as a useful adjunct to standard histopathological procedures.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Perda de Heterozigosidade , Manejo de Espécimes/métodos , Biópsia , Neoplasias Encefálicas/classificação , Cromossomos Humanos Par 10 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 19 , Receptores ErbB/genética , Estudos de Avaliação como Assunto , Deleção de Genes , Glioma/classificação , Humanos , Técnicas Estereotáxicas
12.
J Neuropathol Exp Neurol ; 59(6): 544-58, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10850867

RESUMO

Brain tumors pose a particular challenge to molecular oncology. Many different tumor entities develop in the nervous system and some of them appear to follow distinct pathogenic routes. Molecular genetic alterations have increasingly been reported in nervous system neoplasms. However, a considerable number of affected genes remain to be identified. We present here a comprehensive allelotype analysis of 466 nervous system tumors based on loss of heterozygosity (LOH) studies with 129 microsatellite markers that span the genome. Specific alterations of the EGFR, CDK4, CDKN2A, TP53, DMBT1, NF2, and PTEN genes were analyzed in addition. Our data point to several novel genetic loci associated with brain tumor development, demonstrate relationships between molecular changes and histopathological features, and further expand the concept of molecular tumor variants in neuro-oncology. This catalogue may provide a valuable framework for future studies to delineate molecular pathways in many types of human central nervous system tumors.


Assuntos
Alelos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Humanos , Perda de Heterozigosidade , Repetições de Microssatélites , Biologia Molecular/métodos , Mutação/genética , Análise de Sobrevida
13.
Gene ; 215(1): 131-41, 1998 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-9666103

RESUMO

The STD1 gene of Saccharomyces cerevisiae was isolated independently as a multicopy suppressor of a dominant negative mutation in the TATA-binding protein and of a mutation in the Snf1/Snf4 kinase complex, suggesting that Std1 might couple the Snf1 kinase signaling pathway to the transcriptional machinery. In order to identify the protein domains that specify these activities of the Std1 protein, a plasmid library of randomly mutagenized STD1 genes was screened for loss of function alleles using complementation of the raffinose growth defect of a std1-, mth1- strain as an assay. One missense allele (P236S) with complete loss of function at 30 degreesC and four missense alleles (L173F, E225K, S269L and E274K) that conferred a temperature sensitive phenotype were identified. The C-terminal 20 residues of Std1 were essential for SUC2 derepression, whereas the deletion of the N-terminal 96 residues did not affect SUC2 gene induction. Std1 mutants that lost the ability to induce SUC2, were also unable to suppress the growth defect caused by the expression of the dominant negative TBPDelta57 protein, suggesting that these two genetic screens may be detecting the same biological activity.


Assuntos
Aminoácidos/fisiologia , Proteínas de Transporte/genética , Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/fisiologia , Proteínas de Membrana Transportadoras , Proteínas de Plantas/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , Alelos , Aminoácidos/química , Aminoácidos/genética , Proteínas de Transporte/metabolismo , Clonagem Molecular , DNA Fúngico/análise , DNA Fúngico/genética , DNA Fúngico/isolamento & purificação , Proteínas de Ligação a DNA/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Biblioteca Gênica , Genes Fúngicos/genética , Genes Supressores/genética , Genes Supressores/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular , Mutagênese Sítio-Dirigida , Mutação/genética , Proteínas de Plantas/metabolismo , Polimorfismo Conformacional de Fita Simples , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/fisiologia , Análise de Sequência de DNA , Supressão Genética/genética , Proteína de Ligação a TATA-Box , Temperatura , Fatores de Transcrição/metabolismo , Transcrição Gênica/genética , Ativação Transcricional/genética
14.
FEBS Lett ; 194(2): 305-8, 1986 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-3510130

RESUMO

We report a nonenzymatic reaction which results in the radiolabeling of proteins by 32P-containing nucleoside triphosphates. The labeling reaction does not require any cofactors, but is greatly enhanced by the presence of alcohols. Even under optimal conditions, less than 1% of the protein molecules undergo modification. This nonspecific labeling represents a serious artifact which may become significant in systems involving low levels of specific labeling, such as photoaffinity labeling. Since the reaction is not limited to specific proteins, this may, however, provide a simple and rapid procedure for the preparation of labeled proteins.


Assuntos
Radioisótopos de Fósforo/metabolismo , Ensaio Radioligante , Ribonucleotídeos/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Bovinos , Galinhas , Citidina Trifosfato/metabolismo , Escherichia coli , Guanosina Trifosfato/metabolismo , Ovalbumina/metabolismo , Ensaio Radioligante/métodos , Soroalbumina Bovina/metabolismo
15.
Am J Clin Nutr ; 44(6): 816-24, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3466523

RESUMO

The essential fatty acid deficient (EFAD) chicken was evaluated as a model for cystic fibrosis (CF). Three semipurified diets--(I) 1% hydrogenated coconut oil (HCO), (II) 10% soybean oil + 1% HCO, and (III) 11% HCO--were fed to chickens from hatching to 5, 8, or 11 wk. Groups I and III exhibited poor weight gain and abnormal serum fatty acid patterns characteristic of EFAD. Production of prostaglandin F2 alpha, thromboxane B2, 6-keto-prostaglandin F1 alpha, and prostaglandin E in lung was significantly reduced at 5, 8, and 11 wk in both EFAD groups. Histopathologic examination revealed increased peribronchiolitis in group I compared with II. Incidence of pulmonary lesions in group III was intermediate. These data support the theory that essential fatty acids are necessary to maintain proper lung function. In this respect, the chicken is a good model for studying the relationship between EFAD and pulmonary disease in CF patients.


Assuntos
Galinhas/metabolismo , Fibrose Cística/metabolismo , Ácidos Graxos Essenciais/deficiência , 6-Cetoprostaglandina F1 alfa/biossíntese , Animais , Galinhas/crescimento & desenvolvimento , Fibrose Cística/patologia , Dinoprosta , Modelos Animais de Doenças , Ácidos Graxos/sangue , Pulmão/metabolismo , Pulmão/patologia , Prostaglandinas E/biossíntese , Prostaglandinas F/biossíntese , Tromboxano B2/biossíntese
16.
Am J Clin Nutr ; 43(4): 530-7, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3962906

RESUMO

To determine the amount of isomeric fatty acids in the diets of a segment of the American population, daily food intake was collected, using the duplicate portion method, from eight healthy white adolescent girls for 7 days. The fifty-six diets were analyzed for fatty acids by gas-liquid chromatography. The amount of trans isomers of octadecenoic acid (18:1t) in the diets of the eight girls ranged from 3.5 to 8.2% of total fatty acids with an average of 5.3%. Other trans fatty acids included trans isomers of 14:1 and 16:1, and cis,trans and trans,cis isomers of 18:2. No measurable amounts of trans,trans octadecadienoic acid (18:2tt) were found in the diets of the girls. The total trans fatty acid content of the diets averaged 6.5% of total fatty acids. The daily consumption of total trans fatty acids by the eight girls over a 1 wk period averaged 3.1 g, with 2.6 g of this being 18:1t.


Assuntos
Gorduras na Dieta/análise , Ácidos Graxos/análise , Adolescente , Estatura , Peso Corporal , Criança , Cromatografia Gasosa , Inquéritos sobre Dietas , Ingestão de Energia , Feminino , Humanos , Isomerismo
17.
Am J Clin Nutr ; 39(5): 778-86, 1984 May.
Artigo em Inglês | MEDLINE | ID: mdl-6711479

RESUMO

To study the effects of hydrogenated fat in the maternal diet on lipid composition and prostaglandin content of human milk, eight nursing mothers, 2 months postpartum, were provided with two 5-day diets in a cross-over design with an intervening 2-day period. Diets for the two periods were identical except that sources of hydrogenated fat were used in the meals for one period and nonhydrogenated fat in the other. Trans-isomers of octadecenoic acid (18:lt) comprised 11.8% of the total fatty acids in the hydrogenated fat diet compared with 1.0% in the nonhydrogenated fat diet. The 18:lt content of milk collected daily during hydrogenated fat consumption was 6.5% of the total fatty acids and was significantly higher (p less than 0.01) than the 18:lt content (1.8% of the total fatty acids) of milk collected during nonhydrogenated fat consumption. The amount of 18:lt in the milk was positively correlated (r = 0.909) with the 18:lt content in the previous day's diet. Although detectable concentrations of prostaglandins PGF2 alpha and PGE were found in human milk, their concentrations were not affected by hydrogenated fat in the maternal diet.


Assuntos
Gorduras na Dieta/metabolismo , Leite Humano/análise , Adulto , Ácidos Graxos/análise , Feminino , Humanos , Lactação , Gravidez , Prostaglandinas E/análise , Prostaglandinas F/análise , Estereoisomerismo
18.
Peptides ; 19(3): 599-607, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9533651

RESUMO

In vitro permeation of human calcitonin (hCT), salmon calcitonin (sCT), and the somatostatin analog octreotide (SMS) through excised bovine nasal mucosa was studied applying donor/receiver experiments and confocal laser scanning microscopy. Permeabilities of gonadorelin, buserelin, Hoe013, and of thymopoietin fragments TP5 and TP4 were also included. Apparent permeability coefficients (Peff) ranged between 4 x 10(-5) (SMS) and 1.7 x 10(-5) cm s(-1) (TP4). Such Peff are typical for leaky-type airway epithelia. The order of permeabilities was: SMS >> hCT, sCT > buserelin, Hoe013 >> TP5 > TP4, LHRH. The relatively high permeability of hCT and sCT contrasted to their high molecular weight. At 37 degrees C, the permeability of hCT from mucosal to serosal (m-to-s) was found two-fold higher (p < 0.05) than from serosal to mucosal (s-to-m). Controls using 3H-mannitol showed equal permeabilities in both directions. At 4 degrees C, permeation of hCT was reduced but equal in both directions (m-to-s and s-to-m). As evaluated by confocal laser scanning microscopy, uptake studies with FITC-18-hCT revealed intracellular fluorescence in the epithelial cells, at 10 min/10 microM exposure in the form of fluorescent vesicles. By combination of these findings, an endocytotic pathway is suggested to contribute to the transport of hCT through nasal epithelium.


Assuntos
Calcitonina/metabolismo , Mucosa Nasal/metabolismo , Peptídeos/metabolismo , Animais , Transporte Biológico , Bovinos , Corantes Fluorescentes , Humanos , Técnicas In Vitro , Cinética , Microscopia de Fluorescência , Permeabilidade , Temperatura
19.
J Neurol ; 247(6): 455-60, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10929275

RESUMO

The overall prognosis for patients with glioblastoma multiforme is extremely poor. However, a small proportion of patients enjoy prolonged survival. This study investigated retrospectively the extent to which erroneous histopathological classification may contribute to long-term survival of patients initially diagnosed with "glioblastoma multiforme." We compared two age- and gender-matched patient groups with different postoperative time to tumor progression (TTP), defined as "short-term" for TTP of less than 6 months (n = 54), and "long-term" for TTP of more than 12 months (n = 52). Histological specimens of the corresponding tumors, all primarily diagnosed as glioblastoma multiforme, were reevaluated according to the current World Health Organization (WHO) classification of central nervous system tumors, with the investigators being blinded to clinical outcome. Among the tumors from short-term TTP patients, one tumor (2%) was reclassified as anaplastic oligoastrocytoma (WHO grade III) while the remaining 53 were confirmed as glioblastoma multiforme. In contrast, 13 tumors (25%) from the long-term TTP patients were reclassified, mostly as anaplastic oligodendroglioma (WHO grade III; n = 7) or anaplastic oligoastrocytoma (WHO grade III, n = 2), respectively. In addition, three were reclassified as anaplastic astrocytoma (WHO grade III), and one was identified as anaplastic pilocytic astrocytoma (WHO grade III). Our data indicate that a sizable proportion of glioblastoma patients with long-term survival actually carry malignant gliomas with oligodendroglial features. The correct histopathological recognition of these tumors has not only prognostic but also therapeutic implications, since oligodendroglial tumors are more likely to respond favorably to chemotherapy.


Assuntos
Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Glioblastoma/mortalidade , Glioblastoma/patologia , Adulto , Idoso , Erros de Diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo
20.
Clin Exp Rheumatol ; 1(1): 67-71, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6335853

RESUMO

Sixty-six systemic lupus erythematosus (SLE) patients, 375 healthy female controls and 537 young Caucasian females were examined according to a recently suggested two-stage model for population screening for SLE. This model consisted in: a) administration of a 10-item questionnaire based on the ARA preliminary criteria for SLE; b) search of antinuclear antibodies (ANA) in the persons positive during the first stage. Among the SLE patients, the overall sensitivity of the two-stage screening was 90%, while its specificity in the healthy 375 normals reached 96%. 13% of 537 young Caucasian females answered affirmatively to 3 or more questions of the questionnaire. Out of these, 59 were tested for ANA. Two out of these 59 had a positive ANA test, but no one had SLE at a subsequent clinical survey. These data confirm the validity of this two-stage screening procedure for SLE. While the low prevalence of this disorder in the general population hardly justifies its massive application, the screening might be recommended for survey groups at high risk for SLE.


Assuntos
Lúpus Eritematoso Sistêmico/epidemiologia , Programas de Rastreamento/métodos , Adulto , Anticorpos Antinucleares/análise , Feminino , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Maryland , Projetos Piloto , Inquéritos e Questionários
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