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1.
Aktuelle Urol ; 47(6): 487-490, 2016 12.
Artigo em Alemão | MEDLINE | ID: mdl-27701680

RESUMO

The outpatient forensic aftercare department of the Charité Berlin treated 32 paraphilic sex offenders with GnRH analogues within the past 5 years. Out of those patients, three men suffered from urolithiasis and were in need of treatment. All 3 patients had previously developed osteopenia/osteoporosis while on antiandrogen treatment.This article describes these 3 cases and suggests an intense consideration of the possible occurrence of urolithiasis in sex offenders on antiandrogen treatment.


Assuntos
Acetato de Ciproterona/efeitos adversos , Hormônio Liberador de Gonadotropina/agonistas , Leuprolida/efeitos adversos , Transtornos Parafílicos/tratamento farmacológico , Pamoato de Triptorrelina/efeitos adversos , Urolitíase/induzido quimicamente , Adulto , Oxalato de Cálcio/urina , Acetato de Ciproterona/uso terapêutico , Preparações de Ação Retardada , Seguimentos , Humanos , Cálculos Renais/induzido quimicamente , Cálculos Renais/urina , Leuprolida/uso terapêutico , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Transtornos Parafílicos/urina , Recidiva , Pamoato de Triptorrelina/uso terapêutico , Cálculos Ureterais/induzido quimicamente , Cálculos Ureterais/urina , Urolitíase/terapia , Urolitíase/urina
2.
Acta Physiol (Oxf) ; 187(3): 379-89, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16776663

RESUMO

AIMS: The aim of this study was to characterize the properties of synthetic double-stranded RNA to induce fever and circulating cytokines in guinea pigs with special emphasis on the route of administration and on a putative development of tolerance to this pyrogen. METHODS: Changes in abdominal temperature were recorded in unrestrained animals by use of intra-abdominally implanted radiotransmitters. Circulating concentrations of tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were measured by use of specific bioassays. RESULTS: The pyrogenic effect of double-stranded RNA at a dose of 500 microg kg(-1) depended on the route of its administration. Intra-arterial (i.a.) or intraperitoneal injections of double-stranded RNA induced pronounced fevers and strong elevations of circulating TNF-alpha and IL-6. Intramuscular injections of the synthetic pyrogen caused rather moderate febrile and cytokine responses. Administration of synthetic RNA into artificial subcutaneously implanted Teflon chambers had no pyrogenic and cytokine-inducing effects. I.a. injections of double-stranded RNA, repeated five times at intervals of 3 days, resulted in fevers of similar shape and duration and similar cytokine response patterns. However, the strength of fever and cytokine formation was significantly reduced, although not abolished, in response to the repeated injections compared with the first injection, indicating a partial development of tolerance. CONCLUSIONS: The modulation of the strength of RNA-induced fever, dependent on the route of administration, or the state of partial tolerance to this pyrogen, may thus be related to the formation of pyrogenic cytokines.


Assuntos
Citocinas/sangue , Febre/induzido quimicamente , Pirogênios/efeitos adversos , RNA de Cadeia Dupla/efeitos adversos , Animais , Relação Dose-Resposta a Droga , Cobaias , Injeções Intra-Arteriais , Injeções Intramusculares , Injeções Intraperitoneais , Injeções Subcutâneas , Interleucina-6/sangue , Masculino , Pirogênios/administração & dosagem , RNA de Cadeia Dupla/administração & dosagem , Fator de Necrose Tumoral alfa/sangue
3.
Proteomics ; 1(7): 890-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11503213

RESUMO

We have investigated the suitability of proteomics for identification of tumor-associated antigens. First, we compared the proteomes of nontumorous kidney and renal cell carcinoma (RCC) by two-dimensional gel electrophoresis (2-DE) and silver staining. Protein patterns were markedly different (approximately 800 spots in RCCs versus approximately 1400 spots in kidney). 2-DE immunoblotting revealed five RCC-specific spots, reproducibly reactive with RCC-patient but not healthy donor control sera. Two of these antigens were isolated by preparative 2-DE, and identified by Edman sequencing of tryptic peptides. The first antigen, smooth muscle protein 22-alpha (SM22-alpha), is an actin-binding protein of unknown function predominantly expressed in smooth muscle cells. In situ hybridization revealed that SM22-alpha is not expressed in the malignant cells but in mesenchymal cells of the tumor stroma. The second antigen represents carbonic anhydrase I (CAI), an isoform usually not expressed in kidney. Interestingly, a different isoform (CAXII) has previously been identified by serological expression cloning as an antigen overexpressed in some RCCs. In additional assays, antibodies to recombinant CAI or SM22-alpha were detected in sera from 3/11 or 5/11 RCC patients, respectively, whereas sera from 13 healthy individuals did not react. In conclusion, serological proteome analysis may be a new tool for the identification of tumor-associated antigens.


Assuntos
Antígenos de Neoplasias/análise , Carcinoma de Células Renais/química , Carcinoma de Células Renais/imunologia , Neoplasias Renais/química , Neoplasias Renais/imunologia , Proteoma/análise , Proteoma/imunologia , Testes Sorológicos/métodos , Sequência de Aminoácidos , Antígenos de Neoplasias/genética , Sequência de Bases , Northern Blotting , Anidrase Carbônica I/análise , Anidrase Carbônica I/genética , Anidrase Carbônica I/imunologia , Carcinoma de Células Renais/genética , DNA Complementar/genética , DNA de Neoplasias/genética , Eletroforese em Gel Bidimensional , Humanos , Rim/química , Rim/imunologia , Neoplasias Renais/genética , Proteínas dos Microfilamentos/análise , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/imunologia , Dados de Sequência Molecular , Proteínas Musculares/análise , Proteínas Musculares/genética , Proteínas Musculares/imunologia , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/isolamento & purificação , Proteoma/genética , RNA Mensageiro/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia
4.
Mol Cell Endocrinol ; 172(1-2): 125-34, 2001 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-11165046

RESUMO

The MtT/S somatotroph cell line should be a growth hormone-releasing hormone (GHRH)-responsive model system for the study of physiological control of growth hormone (GH) transcription because GH secretion from these cells is stimulated by GHRH. To examine the GH transcriptional activity of these cells, endogenous GH mRNA levels were measured using a ribonuclease protection assay following treatment under a variety of hormonal conditions. While omission of serum led to reduction of GH mRNA to 22% of control levels by 2 days and to 8% by 5 days (P<0.05 for both), GH mRNA levels were maintained at control values in serum-free medium containing 5 nM dexamethasone and 30 pM triiodothyronine (TDM). However, the addition of 10 nM GHRH under any treatment condition did not significantly alter GH mRNA levels. Characterization of the MtT/S cells showed that GHRH-receptor (GHRH-R) mRNA was detectable by reverse transcription-polymerase chain reaction (RT-PCR) amplification. Measurement of extracellular cAMP showed that the MtT/S cells have basal levels of > or =20 nmol/10(6) cells per h in both serum-containing and serum-free media, and that GHRH had no effect on cAMP levels, suggesting constitutive activation. To rule out the possibility of autocrine stimulation by GHRH produced endogenously, GHRH mRNA was not detectable in MtT/S cells using RT-PCR amplification. The stimulatory G-protein alpha subunit, mutations of which are known to activate adenylate cyclase constitutively in acromegaly, was sequenced but found not to differ from normal pituitary in the regions most commonly mutated. Finally, treatment with 10 microM forskolin, to directly activate adenylate cyclase, increased GH mRNA to 140% of controls in TDM, and to 163% in serum-free medium after 2 days, and to 166% in TDM-treated cells and 174% in serum-free culture after 5 days (all P<0.05). Taken together, these data indicate that although MtT/S cells express the GHRH-R, GHRH cannot stimulate adenylate cyclase to increase GH transcription due to constitutive elevation of cAMP levels, by a means that may be similar to that in cases of acromegaly not caused by oncogenic gsp mutations.


Assuntos
Colforsina/farmacologia , Hormônio Liberador de Hormônio do Crescimento/farmacologia , Hormônio do Crescimento/genética , RNA Mensageiro/efeitos dos fármacos , Adenilil Ciclases/metabolismo , Adenilil Ciclases/farmacologia , Animais , Linhagem Celular , AMP Cíclico/metabolismo , Hormônio Liberador de Hormônio do Crescimento/genética , Proteínas Heterotriméricas de Ligação ao GTP/genética , RNA Mensageiro/metabolismo , Ratos , Receptores de Neuropeptídeos/metabolismo , Receptores de Hormônios Reguladores de Hormônio Hipofisário/metabolismo , Hormônios Tireóideos/farmacologia
5.
Int J Cancer ; 91(2): 180-6, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11146442

RESUMO

The development of human cancer is caused by complex molecular perturbations leading to variable clinical behavior often even in single disease entities. To prove that expression profiling on the protein level can be correlated with clinical data we systematically compared in a pilot study the protein expression patterns obtained by 2-dimensional gel electrophoresis with clinical features in human B-cell chronic lymphocytic leukemia (B-CLL), a disease characterized by broad clinical variability. Statistical methods were devised to analyze the spot pattern from 24 patient samples. This analysis allowed the identification of proteins that clearly discriminated between the patient groups with defined chromosomal characteristics or whose expression levels did correlate with clinical parameters such as patient survival. This report demonstrates that the correlation of large-scale protein expression profiles with clinical data can be used to gain new insights into molecular aspects of a disease. The data described here show that B-CLL patient populations with shorter survival times exhibit changed levels of redox enzymes, heat shock protein 27 and protein disulfide isomerase. These molecules may be potentially involved in drug resistance.


Assuntos
Leucemia Linfocítica Crônica de Células B/genética , Proteínas/análise , Proteoma , Humanos , Cariotipagem , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/mortalidade
6.
Headache ; 40(9): 730-5, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11091291

RESUMO

OBJECTIVE: We conducted the first nonclinic, Internet-based survey of cluster headache to investigate this population with regard to diagnostic problems encountered, effective and ineffective medications, problems obtaining medications through third-party payers, and symptoms as they relate to International Headache Society criteria. BACKGROUND: Previous cluster headache surveys have been at specialty centers. These patients might be different from cluster headache sufferers in the general population. An Internet-based population of cluster headache sufferers who connected to a Web site responded to the questionnaire, and e-mailed it back to our site to be analyzed. We analyzed a total of 789 respondents, 76% men and 28% women. RESULTS: Eighty-seven percent of respondents qualified as having cluster headache according to International Headache Society criteria. However, diagnosis was delayed an average of 6.6 years from the onset of symptoms. The average number of physicians seen before the correct diagnosis was made was 4.3, and the average number of incorrect diagnoses was 3.9. Seventy-one percent of respondents had undergone unnecessary magnetic resonance or computed tomography scans, and 4% had unnecessary sinus or deviated septum surgery. We found that many inappropriate medications such as propranolol, amitriptyline, and antibiotics were prescribed and that successful medications for clusters such as sumatriptan and oxygen were often denied due to a failure to understand the nature of this disorder. Seventy-seven percent of respondents were smokers. Seventy-four percent stopped smoking in an attempt to improve their condition; however, only 3% experienced relief. CONCLUSIONS: The most alarming finding was the delay in diagnosing cluster headache in this population--an average of 6.6 years. The selection of medications demonstrated to be successful in the treatment of clusters proved effective for the majority of this population. Many respondents reported being denied some of these effective medications by their physicians or third-party payers. Using International Headache Society criteria for cluster headache, 87% of the respondents should have been correctly diagnosed by the first physician seen.


Assuntos
Cefaleia Histamínica/diagnóstico , Erros de Diagnóstico , Adulto , Idade de Início , Cefaleia Histamínica/tratamento farmacológico , Coleta de Dados , Feminino , Humanos , Internet , Masculino , Transtornos de Enxaqueca/diagnóstico , Inquéritos e Questionários , Fatores de Tempo
7.
Endocrine ; 13(1): 71-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11051049

RESUMO

Reduction of mRNA expression from the endogenous GH gene by insulin-like growth factor 1 (IGF-1) in somatotroph-like rat MtT/S cells was measured. GH mRNA levels were reduced by 65 nM IGF-1 treatment in a time-dependent manner over 5 d of culture with a calculated GH mRNA half-life of 50 h, in line with previous values from primary cultures. Inhibition of inositol 3-phosphate kinase by wortmannin or LY-294,002 treatment was ineffective in blocking IGF-1 decreases in GH mRNA, as was inhibition of MAP kinase activity by PD 098059. The inhibition by IGF-1 also did not regulate Pit-1 (GHF-1) mRNA levels, which were constant during 65 nM IGF-1 treatment. MtT/S cells were shown to have both IGF-1 and insulin receptors as detected by Western blotting. There was also shown to be the suggestion of "hybrid" receptors containing different beta chains from each of these related heterotetrameric receptors. Analysis of the effects of IGF-1 and insulin on MtT/S cells showed that each reduced GH mRNA in a dose-dependent manner gave a calculated EC50 of 15.5 nM for IGF-1 and 0.6 nM for insulin, suggesting that the respective receptors for each hormone were activated. However, GH mRNA response to IGF-1 treatment was "ultrasensitive," exhibiting a switch-like effect; below 10 nM IGF-1, there was no decline in GH mRNA, but then maximal reduction occurred at IGF-1 concentrations above 20 nM. The degree of this ultrasensitive effect was calculated from the Hill equation for cooperativity, with a Hill coefficient of -4.1, greater than the classic cooperativity exhibited by hemoglobin binding to oxygen. The ultrasensitive response was specific for IGF-1, as insulin did not display this effect. These results suggest that the response evoked by the IGF-1 receptor could act as a binary molecular switch controlling GH mRNA expression in somatotrophs.


Assuntos
Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Adeno-Hipófise/metabolismo , RNA Mensageiro/metabolismo , Androstadienos/farmacologia , Animais , Western Blotting , Linhagem Celular , Meios de Cultura , Proteínas de Ligação a DNA/genética , Corantes Fluorescentes , Expressão Gênica , Técnicas de Imunoadsorção , Insulina/farmacologia , Cinética , Ratos , Receptor IGF Tipo 1/análise , Receptor de Insulina/análise , Ribonucleases , Fator de Transcrição Pit-1 , Fatores de Transcrição/genética , Wortmanina
8.
Virology ; 269(1): 18-25, 2000 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-10725194

RESUMO

Human herpesvirus 8 (HHV-8) or Kaposi's sarcoma-associated herpesvirus (KSHV) is the only known human member of the Rhadinovirus genus of the gammaherpesvirus subfamily. Antibodies against peptides representing portions of the amino- and carboxyl-termini of HHV-8 gB were produced and used to detect gB expression in Vero cells transfected with the gB gene, in the HHV-8-harboring cell line, BCBL-1, and in purified virions. Expression of gB was detected in approximately 3% of uninduced BCBL-1 cells, while up to 30% of the cells expressed gB after 12-O-tetradecanoylphorbol-13-acetate (TPA) induction of virus replication. Indirect immunofluorescence assays and confocal microscopy showed that gB was distributed throughout the cytoplasm of BCBL-1 cells and transfected Vero cells. Immunoblot analyses of virion preparations revealed the presence of full-length as well as two smaller than full-length gB-derived species corresponding to the amino- and carboxy-terminal portions of gB, respectively. Biochemical analysis of the gB carbohydrate moieties using glycosylation inhibitors revealed that gB contained N-linked oligosaccharides of the high-mannose type, characteristic of precursor carbohydrate chains added in the endoplasmic reticulum.


Assuntos
Herpesvirus Humano 8/química , Fragmentos de Peptídeos/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas do Envelope Viral/metabolismo , Amidoidrolases/metabolismo , Animais , Western Blotting , Células COS , Chlorocebus aethiops , Citoplasma/virologia , Técnica Indireta de Fluorescência para Anticorpo , Glicosilação/efeitos dos fármacos , Herpesvirus Humano 8/efeitos dos fármacos , Herpesvirus Humano 8/isolamento & purificação , Herpesvirus Humano 8/metabolismo , Hexosaminidases/metabolismo , Manose/metabolismo , Peso Molecular , Fragmentos de Peptídeos/biossíntese , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase , Acetato de Tetradecanoilforbol/farmacologia , Transfecção , Células Tumorais Cultivadas , Tunicamicina/farmacologia , Células Vero , Proteínas do Envelope Viral/biossíntese , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética , Replicação Viral/efeitos dos fármacos
9.
Arch Virol ; 144(5): 957-71, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10416377

RESUMO

Turnip vein-clearing virus (TVCV) and tobacco mosaic virus (TMV) represent subgroups of tobamoviruses infecting cruciferous and solanaceous plants, respectively. To identify adaptations that may have been necessary in the evolution of the TVCV subgroup from a TMV-like ancestor, the infection of turnip plants by TMV and by chimeras between TMV and TVCV was explored. TMV accumulated at spatially limited sites on inoculated turnip leaves as determined by leaf skeleton hybridization. A plasmid DNA containing a complete TVCV cDNA, when transcribed in vitro, produced RNA that was infectious to tobacco and turnip plants. TVCV-TMV chimeric genomes with junctions within coding regions were not infectious to tobacco, though the movement protein (MP) chimera was infectious to tobacco with a TMV MP transgene. Reciprocal chimeras with junctions between genes were infectious to tobacco. TVCV with a TMV MP gene infected turnips. The other tested chimeras were not detected in non-inoculated leaves, but were found in the inoculated leaves. Thus, the TMV MP is not responsible for the limitation of TMV spread in turnips.


Assuntos
Brassica/virologia , Nicotiana/virologia , Plantas Tóxicas , Vírus do Mosaico do Tabaco/fisiologia , Primers do DNA , Folhas de Planta , Proteínas do Movimento Viral em Plantas , Plasmídeos , RNA Viral/genética , Proteínas Recombinantes de Fusão/metabolismo , Mapeamento por Restrição , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade da Espécie , Vírus do Mosaico do Tabaco/genética , Vírus do Mosaico do Tabaco/patogenicidade , Tobamovirus/genética , Tobamovirus/patogenicidade , Tobamovirus/fisiologia , Transcrição Gênica , Proteínas Virais/genética , Proteínas Virais/metabolismo
10.
J Pediatr Endocrinol Metab ; 11(5): 623-30, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9829213

RESUMO

We studied a 14 year-old girl with extreme short stature (-9.5 SDS), normal psychomotor development and signs of progressive hypothyroidism. Basal IGF-I and T4 were low. Serum GH was low after insulin-induced hypoglycemia and GH-releasing hormone administration. Both TSH and prolactin were low and did not rise after TRH administration. Gonadotropins were normal and cortisol levels were elevated. In contrast, DHEA-S levels were low and she did not develop pubic hair until 26 years of age, compatible with deficiency of a putative pituitary adrenal androgen stimulating hormone. Pituitary size was reduced on magnetic resonance imaging. Sequencing of the Pit-1 gene revealed a heterozygous C to T transition in codon 271 resulting in substitution of tryptophane for a highly conserved arginine. Her parents were homozygous normal for this locus indicating a de novo mutation with dominant expression. Genetic and phenotypic heterogeneity of patients with Pit-1 gene mutations, particularly the R271W mutation, may reveal further information about the nature of genetic silencing, imprinting, and epigenetic inheritance. The relationship of Pit-1 deficiency to abnormal adrenal secretion remains to be elucidated.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Hipopituitarismo/etiologia , Mutação , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Adolescente , Brasil , DNA/análise , Feminino , Transtornos do Crescimento/etiologia , Hormônio do Crescimento Humano/sangue , Hormônio do Crescimento Humano/deficiência , Humanos , Hipotireoidismo/etiologia , Fator de Crescimento Insulin-Like I/análise , Linhagem , Reação em Cadeia da Polimerase , Prolactina/sangue , Prolactina/deficiência , Tireotropina/sangue , Tireotropina/deficiência , Tiroxina/sangue , Fator de Transcrição Pit-1
11.
J Virol ; 70(10): 7049-55, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8794349

RESUMO

Alterations in plasma membrane function are induced by many cytopathic viruses, including human immunodeficiency virus type 1 (HIV-1). These alterations can result in changes in the intracellular content of ions and other small molecules and can contribute to cytolysis and death of the infected cell. The pH-sensitive fluorescent probe 2',7'-bis(2-carboxyethyl)-5,6-carboxyfluorescein-acetoxymethyl ester was used to quantitate intracellular pH (pHi) in HIV-1-infected T cells. Infection of cells from the CD4+ T-lymphoblastoid line HUT-78 (RH9 subclone) with HIV-1 strain LAI resulted in a significant decrease of pHi, from approximately 7.2 in mock-infected cells to below 6.7 by day 4 after infection, when cells were undergoing acute cytopathic effects. The pHi in persistently infected cells that survived the acute cytopathic effects of HIV-1 was approximately 6.8 to 7.0. Studies with amiloride, an inhibitor of the Na+/H+ exchange system, suggest that HIV-1-induced intracellular acidification in lymphocytes is due, in part, to dysfunction of this plasma membrane ion transport system. The alterations in pHi may mediate certain cytopathic effects of HIV-1, thereby contributing to depletion of CD4+ T lymphocytes in patients with AIDS.


Assuntos
Linfócitos T CD4-Positivos/virologia , Infecções por HIV/metabolismo , HIV-1 , Linfócitos T CD4-Positivos/metabolismo , Linhagem Celular , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/virologia , Humanos , Concentração de Íons de Hidrogênio , Transporte de Íons
12.
Biochem J ; 318 ( Pt 1): 213-8, 1996 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-8761474

RESUMO

The 2A proteinases of human rhinoviruses are cysteine proteinases with marked similarities to serine proteinases. In the absence of a three-dimensional structure, we developed a genetical screening system for proteolytic activity and identified Phe-130 as a key residue. The mutation Phe-130-->Tyr almost completely inhibited enzyme activity at 37 degrees C; activity was, however, partially restored by the following exchanges: Ser-27-->Pro, His-135-->Arg or His-137-->Arg. To investigate this phenotypic reversion, 2A proteinases with the mutations Phe-130-->Tyr, Phe-130-->Tyr/His-135-->Arg, Phe-130-->Tyr/His-137-->Arg, His-135-->Arg or His-137-->Arg were expressed in Escherichia coli and purified. None of these mutations affected the affinity of the enzyme for a peptide substrate. However, the temperature-dependence of enzyme activity, as assayed by cleavage of a peptide substrate and by monitoring the toxicity of the proteinases towards the E. coli strain BL21(DE3), and the structural stability, as monitored by 8-anilino-I-naphthalenesulphonic acid fluorescence and CD spectrometry, were affected. The thermal transition temperatures for both the activity and the stability of the Phe-130-->Tyr 2A proteinase were reduced by about 17 degrees C compared with the wild-type enzyme. The presence of the additional mutations His-135-->Arg or His-137-->Arg in the Phe-130-->Tyr mutant increased temperature stability by 3 degrees C and 6 degrees C respectively. Thus essential interactions exist within the C-terminal domain of human rhinoviral 2A proteinases which contribute to the overall stability and integrity of the enzyme.


Assuntos
Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Rhinovirus/enzimologia , Proteínas Virais , Sítios de Ligação , Dicroísmo Circular , Cisteína Endopeptidases/química , Estabilidade Enzimática , Escherichia coli/genética , Genes Virais , Testes Genéticos , Humanos , Cinética , Óperon Lac , Mutagênese Sítio-Dirigida , Mutação Puntual , Desnaturação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Temperatura , Transformação Genética
13.
Mol Pharmacol ; 49(1): 73-80, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8569715

RESUMO

A direct phosphate transfer reaction from the G protein beta subunits to either Gs alpha or Gi alpha has been proposed to account for the ability of thiophosphorylated transducin beta gamma-dimers to bidirectionally regulate adenylyl cyclase activity in human platelet membranes. We searched for experimental evidence for this reaction. Incubation of human platelet membranes with [35S]guanosine-5'-(3-O-thio)triphosphate ([35S]GTP gamma S) results in the predominant incorporation of [35S]thiophosphate into a 36-kDa protein, which comigrates with the G protein beta subunit and is immunoprecipitated by a beta subunit-specific antiserum. Thiophosphorylation of the beta subunit is specific for guanine nucleotides and abolished by the histidine-modifying agent diethylpyrocarbonate and heat and acid treatment. Dephosphorylation of [35S]thiophosphorylated beta subunits is accelerated in the presence of GDP, but not ADP, UDP, or guanosine-5'-(2-O-thio)diphosphate. Neither the thiophosphorylation nor the dephosphorylation is sensitive to receptor agonists (alpha 2-adrenergic, A2 adenosine, thrombin, or insulin), and purified G protein alpha subunits do not act as thiophosphate donors. An approach was designed to demonstrate direct thiophosphate transfer to protein-bound nucleotides; platelet membranes were sequentially exposed to NaIO4, NaCNBH3, and NaBH4, an oxidation-reduction step that covalently incorporates prebound nucleotides into proteins. Under these conditions, multiple radiolabeled proteins are visualized on subsequent addition of [35S]GTP gamma S. This reaction is specific because both oxidation and reduction are required and pretreatment of platelet membranes with 2',3'-dialdehyde GTP gamma S or diethylpyrocarbonate blocks the subsequent labeling in oxidized and reduced membranes. The G protein beta subunit may participate in this thiophosphate transfer reaction. Most important, however, no labeled G protein alpha subunits (Gs alpha and Gi alpha) were recovered by immunoprecipitation from oxidized and reduced membranes subsequent to the addition of [35S]GTP gamma S. Thus, our results clearly rule out the existence of a postulated G protein activation by phosphate transfer reactions, which lead to the formation of GTP from GDP prebound to the alpha subunit.


Assuntos
Plaquetas/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Compostos Organotiofosforados/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Membrana Celular/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Técnicas In Vitro , Fosforilação
14.
Gene ; 166(2): 331-2, 1995 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-8543186

RESUMO

Turnip vein-clearing virus (TVCV) is a tobamovirus related to ribgrass mosaic virus. We report the nucleotide (nt) sequences of the 5'-untranslated region (UTR) and the 3'-half of the TVCV genome (the 3' region of the 182-kDa protein-encoding gene, as well as the movement protein and coat protein genes and the 3'-UTR). The determination completes the nt sequence of the cDNA of TVCV.


Assuntos
Tobamovirus/genética , Sequência de Aminoácidos , Sequência de Bases , DNA Complementar/genética , Homologia de Genes , Genes Virais , Dados de Sequência Molecular , Proteínas Estruturais Virais/genética
15.
Protein Sci ; 4(12): 2526-31, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8580843

RESUMO

Recently, protease 2A of human rhinovirus 2 (HRV2 2A) was shown to require a zinc ion for the formation of an active enzyme although zinc is not involved mechanistically. The data presented clearly show that the zinc ion bound to a picornaviral-specific motif represents an essential component of the native structure, probably representing a new Zn-binding motif. This structure, containing mostly beta-strand elements as shown by CD spectroscopy, changes drastically upon removal of zinc. The zinc-depleted form does represent an intermediate with mostly unchanged secondary structure, but not a fully denatured random coil as obtained by guanidinium hydrochloride. This is indicated by the blue-shifted fluorescence spectra and by CD. The native protein exhibited a cooperative phase transition at 53 degrees C. In contrast, the zinc-depleted form did not show any transition at all, again demonstrating the stabilizing role of the zinc ion. A structural intermediate was observed during thermal and pH denaturation that may represent a molten globule, as suggested by its ANS binding.


Assuntos
Cisteína Endopeptidases/química , Proteínas Virais , Zinco/química , Dicroísmo Circular , Cisteína Endopeptidases/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio , Desnaturação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Espectrometria de Fluorescência , Relação Estrutura-Atividade , Termodinâmica , Ureia , Zinco/metabolismo
16.
Oncogene ; 11(7): 1299-307, 1995 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-7478550

RESUMO

There is now much evidence to suggest that the p53 tumour suppressor protein functions to monitor the integrity of the genome. When DNA damage is detected, p53 suppresses cell growth to allow repair or directs the cell into apoptosis. The mechanism of action of p53 is as yet unclear but recent evidence has accumulated to suggest that p53 might act by regulating gene expression. Consistent with this model, p53 can both activate and repress a number of viral and cellular promoters. p53 has also been shown to bind to the CCAAT-binding Factor and TATA-binding protein (TBP), and there is direct evidence that p53 represses in vitro transcription by preventing TBP from binding DNA. We now provide evidence that p53 can repress transcription from the SV40 promoter by disrupting DNA/protein complexes involving transcription factor Sp1.


Assuntos
Vírus 40 dos Símios/genética , Fatores de Transcrição/biossíntese , Transcrição Gênica/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Animais , Sequência de Bases , Primers do DNA , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica , Células HeLa , Humanos , Camundongos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Ligação Proteica , Fatores de Transcrição/metabolismo
17.
Autoimmunity ; 20(2): 135-42, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7578870

RESUMO

An apparently high frequency of Graves' disease encountered in New Orleans, Louisiana, prompted an investigation for a possible infectious agent that might be triggering the disease in genetically susceptible individuals. We studied 40 patients with Graves' disease, and compared them to the following groups of controls: age and gender matched healthy subjects; patients with multinodular goiter (non-autoimmune thyroid controls); patients with chronic lymphocytic thyroiditis (autoimmune thyroid disease controls) and additional organ or tissue specific autoimmune controls exclusive of thyroid autoimmunity, including patients with Type I diabetes and other endocrine autoimmune complex disorders. Serum antibodies against a prototypic strain of a human intracisternal A-type retroviral particle type 1 (HIAP-1) were detected by a sensitive and specific immunoblotting assay. In 87.5% (35/40) of the Graves' disease patients there was a positive reaction against several HIAP-1-associated proteins, predominantly 97 Kd and 80 Kd, with only 5 showing no reactivity to any. In contrast, 2% (2/105) of sera from normal controls showed positive reactivity. Furthermore, only 10% (1/10) of sera from multinodular goiter control patients and 10% (1/10) of Hashimoto's patients showed reactivity (p < 0.0005). Sera from 3 of 20 (15%) of Type I diabetic patients none of whom had Graves' disease, showed reactivity but there was no reactivity in 9 other patients with one or more of the endocrine autoimmune complex disorders, including Addison's disease, vitiligo, myasthenia gravis and pernicious anemia. In addition we studied two individuals with Graves' disease from each of two families residing outside Louisiana, all of whom were positive for these antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Doença de Graves/virologia , Infecções por Retroviridae/imunologia , Adulto , Feminino , Genes de Partícula A Intracisternal/imunologia , Doença de Graves/etiologia , Doença de Graves/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas dos Retroviridae/isolamento & purificação
18.
J Gen Virol ; 75 ( Pt 8): 1943-51, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8046396

RESUMO

The mechanism for down-regulation of E1a expression by products encoded in the E3 transcription unit of human adenovirus types 2 and 5, that occurs in infected L929 cells, has been investigated further. We show that the phenomenon occurs in different mouse cells and also in some human cells suggesting that the observations have relevance to natural human infections. We also provide evidence that probably all viral proteins are down-regulated by E3 products, although to different extents, but that host proteins are unaffected. Whereas E1a protein levels and synthesis are reduced in the presence of E3 products, E1a protein half-life and polysomal E1a RNA levels and size distribution are not. These data suggest that E3 products down-regulate E1a protein levels by interfering with the translation of E1a-specific mRNA. Studies were additionally carried out with mutant adenoviruses containing different defects in the E3 transcription unit. Based on these studies it seems likely that the E3 14.5K and 10.4K proteins are crucially involved in E1a down-regulation. Our data are discussed in terms of strategies for immune evasion by group C human adenoviruses.


Assuntos
Proteínas E1A de Adenovirus/biossíntese , Proteínas E3 de Adenovirus/biossíntese , Adenovírus Humanos/genética , Regulação para Baixo , Biossíntese de Proteínas , Proteínas E1A de Adenovirus/genética , Proteínas E3 de Adenovirus/genética , Animais , Células Cultivadas , Regulação Viral da Expressão Gênica , Meia-Vida , Humanos , Camundongos , RNA Mensageiro/metabolismo , Especificidade da Espécie
20.
Biochem J ; 298 Pt 3: 719-25, 1994 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8141788

RESUMO

Human interferon-alpha 2c (IFN-alpha 2c) was produced in Escherichia coli under the control of the alkaline phosphatase promoter using a periplasmic expression system. Compared with other leader sequences, the heat-stable enterotoxin II leader of E. coli (STII) resulted in the highest rate of correct processing as judged by Western-blot analysis. The fermentation was designed as a batch-fed process in order to obtain a high yield of biomass. The processing rate of IFN-alpha 2c could be increased from 25% to more than 50% by shifting the fermentation pH from 7.0 to 6.7. IFN-alpha 2c extracted from the periplasm was purified by a new four-step chromatographic procedure. Whereas cytoplasmically produced IFN-alpha 2c does not have its full native structure, IFN-alpha 2c extracted from the periplasm was found to be correctly folded, as shown by c.d. spectroscopy. Peptide-map analysis in combination with m.s. revealed the correct formation of disulphide bridges. N-terminal sequence analysis showed complete removal of the leader sequence, creating the authentic N-terminus starting with cysteine.


Assuntos
Escherichia coli/genética , Expressão Gênica , Interferon Tipo I/genética , Fosfatase Alcalina/genética , Sequência de Aminoácidos , Sequência de Bases , Western Blotting , Cromatografia , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Fermentação , Humanos , Interferon Tipo I/química , Dados de Sequência Molecular , Mapeamento de Peptídeos , Regiões Promotoras Genéticas , Dobramento de Proteína , Sinais Direcionadores de Proteínas/química , Proteínas Recombinantes
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