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1.
Artigo em Inglês | MEDLINE | ID: mdl-22229040

RESUMO

Objective. To identify whether a standardised Echinacea formulation is effective in the prevention of respiratory and other symptoms associated with long-haul flights. Methods. 175 adults participated in a randomised, double-blind placebo-controlled trial travelling back from Australia to America, Europe, or Africa for a period of 1-5 weeks on commercial flights via economy class. Participants took Echinacea (root extract, standardised to 4.4 mg alkylamides) or placebo tablets. Participants were surveyed before, immediately after travel, and at 4 weeks after travel regarding upper respiratory symptoms and travel-related quality of life. Results. Respiratory symptoms for both groups increased significantly during travel (P < 0.0005). However, the Echinacea group had borderline significantly lower respiratory symptom scores compared to placebo (P = 0.05) during travel. Conclusions. Supplementation with standardised Echinacea tablets, if taken before and during travel, may have preventive effects against the development of respiratory symptoms during travel involving long-haul flights.

2.
Braz J Med Biol Res ; 40(3): 357-66, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17334533

RESUMO

The effects of haloperidol and olanzapine on polysomnographic measures made in bipolar patients during manic episodes were compared. Twelve DSM-IV mania patients were randomly assigned to receive either haloperidol (mean +/- SD final dosage: 5.8 +/- 3.8 mg) or olanzapine (mean +/- SD final dosage: 13.6 +/- 6.9 mg) in a 6-week, double-blind, randomized, controlled clinical trial. One-night polysomnographic evaluation was performed before and after the haloperidol or olanzapine treatment. Psychopathology and illness severity were rated respectively with the Young Mania Rating Scale (YMRS) and the Clinical Global Impressions - Bipolar version (CGI-BP). There was a significant improvement in the YMRS and CGI-BP scores at the end of the study for both groups. Mixed ANOVA used to compare the polysomnographic measures of both drugs demonstrated significant improvement in sleep measures with olanzapine. In the olanzapine group, statistically significant time-drug interaction effects on sleep continuity measures were observed: sleep efficiency (mean +/- SEM pre-treatment value: 6.7 +/- 20.3%; after-treatment: 85.7 +/- 10.9%), total wake time (pre-treatment: 140.0 +/- 92.5 min; after-treatment: 55.2 +/- 44.2 min), and wake time after sleep onset (pre-treatment: 109.7 +/- 70.8 min; after-treatment: 32.2 +/- 20.7 min). Conversely, improvement of polysomnographic measures was not observed for the haloperidol group (P > 0.05). These results suggest that olanzapine is more effective than haloperidol in terms of sleep-promoting effects, although olanzapine is comparatively as effective as haloperidol in treating mania. Polysomnography records should provide useful information on how manic states can be affected by psychopharmacological agents.


Assuntos
Antipsicóticos/uso terapêutico , Benzodiazepinas/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Haloperidol/uso terapêutico , Sono/efeitos dos fármacos , Adulto , Análise de Variância , Transtorno Bipolar/psicologia , Escalas de Graduação Psiquiátrica Breve , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Olanzapina , Polissonografia/efeitos dos fármacos , Resultado do Tratamento
3.
Braz. j. med. biol. res ; 40(3): 357-366, Mar. 2007. tab
Artigo em Inglês | LILACS | ID: lil-441759

RESUMO

The effects of haloperidol and olanzapine on polysomnographic measures made in bipolar patients during manic episodes were compared. Twelve DSM-IV mania patients were randomly assigned to receive either haloperidol (mean ± SD final dosage: 5.8 ± 3.8 mg) or olanzapine (mean ± SD final dosage: 13.6 ± 6.9 mg) in a 6-week, double-blind, randomized, controlled clinical trial. One-night polysomnographic evaluation was performed before and after the haloperidol or olanzapine treatment. Psychopathology and illness severity were rated respectively with the Young Mania Rating Scale (YMRS) and the Clinical Global Impressions - Bipolar version (CGI-BP). There was a significant improvement in the YMRS and CGI-BP scores at the end of the study for both groups. Mixed ANOVA used to compare the polysomnographic measures of both drugs demonstrated significant improvement in sleep measures with olanzapine. In the olanzapine group, statistically significant time-drug interaction effects on sleep continuity measures were observed: sleep efficiency (mean ± SEM pre-treatment value: 6.7 ± 20.3 percent; after-treatment: 85.7 ± 10.9 percent), total wake time (pre-treatment: 140.0 ± 92.5 min; after-treatment: 55.2 ± 44.2 min), and wake time after sleep onset (pre-treatment: 109.7 ± 70.8 min; after-treatment: 32.2 ± 20.7 min). Conversely, improvement of polysomnographic measures was not observed for the haloperidol group (P > 0.05). These results suggest that olanzapine is more effective than haloperidol in terms of sleep-promoting effects, although olanzapine is comparatively as effective as haloperidol in treating mania. Polysomnography records should provide useful information on how manic states can be affected by psychopharmacological agents.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Antipsicóticos/uso terapêutico , Benzodiazepinas/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Haloperidol/uso terapêutico , Sono/efeitos dos fármacos , Escalas de Graduação Psiquiátrica Breve , Método Duplo-Cego , Polissonografia/efeitos dos fármacos , Resultado do Tratamento
4.
Nucleic Acids Res ; 28(9): 1849-58, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10756182

RESUMO

A new photocrosslinking purine analog was synthesized and evaluated as a transcription substrate for Escherichia coli RNA polymerase. This analog, 8-[(4-azidophenacyl)thio]adenosine 5'-triphosphate (8-APAS-ATP) contains an aryl azide photocrosslinking group that is attached to the ATP base via a sulfur-linked arm on the 8 position of the purine ring. This position is not involved in the normal Watson-Crick base pairing needed for specific hybridization. Although 8-APAS-ATP could not replace ATP as a substrate for transcription initiation, once stable elongation complexes were formed, 8-APAS-AMP could be site-specifically incorporated into the RNA, and this transcript could be further elongated, placing the photoreactive analog at internal positions in the RNA. Irradiation of transcription elongation complexes in which the RNA contained the analog exclusively at the 3' end of an RNA 22mer, or a 23mer with the analog 1 nt from the 3' end, produced RNA crosslinks to the RNA polymerase subunits that form the RNA 3' end binding site (beta, beta'). Both 8-APAS-AMP and the related 8-azido-AMP were subjected to conformational modeling as nucleoside monophosphates and in DNA-RNA hybrids. Surprisingly, the lowest energy conformation for 8-APAS-AMP was found to be syn, while that of 8-azido-AMP was anti, suggesting that the conformational properties and transcription substrate properties of 8-azido-ATP should be re-evaluated. Although the azide and linker together are larger in 8-APAS-ATP than in 8-N(3)-ATP, the flexibility of the linker itself allows this analog to adopt several different energetically favorable conformations, making it a good substrate for the RNA polymerase.


Assuntos
Monofosfato de Adenosina/química , Trifosfato de Adenosina/análogos & derivados , Proteínas de Ligação a RNA/química , RNA/química , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/química , Azidas/química , Reagentes de Ligações Cruzadas , RNA Polimerases Dirigidas por DNA/metabolismo , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico , Transcrição Gênica
5.
J Mol Recognit ; 12(6): 337-45, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10611643

RESUMO

Labeled nucleic acid probes are used as diagnostic tools by detecting changes in gene expression upon hybridization to target RNAs or DNAs that are related to specific disease genes. 5-[S-(2, 4-Dinitrophenyl)-thio]-2'-deoxyuridine analog represents an excellent nucleic acid label, containing the DNP group which functions both as a probe and as a precursor for the introduction of a variety of fluorescent groups. This study describes thermal denaturation hybridization experiments with oligonucleotides containing the 5-[S-(2,4-dinitrophenyl)-thio]-2'-deoxyuridine analog. Using molecular modeling techniques, the effects of this analog on the hybrid structure and stability were examined, including (i) analog conformation, (ii) hydrogen bonding, (iii) stacking interactions and (iv) hybrid helical geometry. This analog does not prohibitively affect the hybrid thermal stability and incorporation of the analog does not compromise the structural integrity of the double helix. In particular, the sequence-dependence of the analog effects and the dependence on the modification site relative to the end(s) of the helix were investigated. Findings described here should provide guidelines in the rational design of nucleic acid probes.


Assuntos
Sondas de DNA/química , Desoxiuridina/análogos & derivados , Corantes Fluorescentes/química , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico , Simulação por Computador , Sondas de DNA/síntese química , Desoxiuridina/química , Desenho de Fármacos , Corantes Fluorescentes/síntese química , Temperatura Alta , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Desnaturação de Ácido Nucleico , Oligodesoxirribonucleotídeos/metabolismo , Relação Estrutura-Atividade
7.
Nucleic Acids Res ; 27(5): 1369-76, 1999 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9973628

RESUMO

We report the synthesis and characterization of 5-thioacetamidofluorescein-uridine 5'-triphosphate (5-SF-UTP), and its application to the characterization of the environment of the nascent RNA during trans-cription. This analog specifically replaced UTP as a transcription substrate for Escherichia coli and T7 RNA polymerases, and yeast RNA polymerase III. Escherichia coli transcription complexes containing analog incorporated at only position +21 of the RNA were prepared. The RNA was then elongated in the absence of analog, moving the fluorescent group further away from the enzyme active site, and the fluorescence polarization was measured. Analog positioned near the 3' end of the transcript exhibited significantly increased polarization relative to that of free probe, consistent with the constrained environment of the RNA in the DNA-RNA hybrid. Analog positioned 14 nucleotides from the 3' end exhibited significantly decreased polarization relative to that at the 3' end of the RNA, but only slightly above that of free RNA, suggesting that the probe was on the solvent-exposed surface of the polymerase. Molecular modeling of these analog-substituted RNAs produced structures consistent with the experimental data. The excellent substrate properties of this analog make it useful for the characterization of the environment of RNA not only during transcription and translation, but in any type of ribonucleoprotein complex.


Assuntos
Escherichia coli/genética , Sondas RNA/química , Fatores de Transcrição/genética , Uridina Trifosfato/análogos & derivados , Sequência de Bases , DNA/química , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/enzimologia , Polarização de Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Modelos Moleculares , Estrutura Molecular , Hibridização de Ácido Nucleico , Sondas RNA/síntese química , Transcrição Gênica , Uridina Trifosfato/síntese química , Uridina Trifosfato/química
8.
J Mol Biol ; 282(2): 227-39, 1998 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-9735283

RESUMO

Proteins in a partially fractionated Escherichia coli extract that interact with the nascent RNA in active transcription complexes from several promoters were detected using the photocrosslinking ribonucleotide analogs 5-(azidophenacyl)thio-UTP or 5-(azidophenacyl)thio-CTP as transcription substrates. Upon irradiation of ternary transcription complexes, several extract proteins were crosslinked to the RNA. Most notably, a small protein was crosslinked to the RNA in complexes on seven of nine templates tested. This protein was purified and sequenced and found to match a hypothetical protein, MsmC/CspE, recently shown to be involved in chromatin partitioning. CspE has 69% amino acid sequence identity with the major cold shock protein in E. coli, CspA, which has been shown to bind to a DNA sequence designated the Y box, with the sequence 5'-ATTGG. Of the nine templates tested, CspE was found to be most heavily crosslinked to RNA from the lambda PR' promoter, which is modified by the Q antiterminator protein. CspE was very heavily crosslinked to RNA only ten nucleotides long in initial ternary complexes on this promoter, but not to this same RNA after it had been released from the transcription complex. However, even when present from the start of transcription, CspE did not crosslink to the RNA 82 nucleotides long in elongation complexes from this same promoter. Despite the loss of interaction with the RNA after polymerase had left the promoter, CspE inhibited Q-mediated transcriptional antitermination from PR' in vitro almost 200 nucleotides downstream from the promoter, presumably by interaction with the Y box DNA upstream from PR', which overlaps with the binding site for the Q. A potential role for CspE and transcription in chromosome condensation and nucleoid structure is discussed.


Assuntos
Proteínas de Bactérias/metabolismo , Cromatina/metabolismo , Proteínas de Escherichia coli , Proteínas de Choque Térmico/metabolismo , RNA Bacteriano/metabolismo , Transcrição Gênica , Sequência de Aminoácidos , Sequência de Bases , Reagentes de Ligações Cruzadas , DNA Bacteriano/metabolismo , Proteínas de Ligação a DNA/metabolismo , Escherichia coli , Proteínas de Choque Térmico/isolamento & purificação , Proteínas de Choque Térmico/fisiologia , Dados de Sequência Molecular , Elongação Traducional da Cadeia Peptídica/genética , Moldes Genéticos
9.
Bioconjug Chem ; 7(4): 401-12, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8853453

RESUMO

A new nucleotide analogue was developed for site-specific incorporation of a reactive thiol group into DNA. This creates a unique site for the post-synthetic modification of that nucleotide with a variety of molecular tags, such as photo-cross-linkers and fluorescent or spin-label moieties. 5'-O-(4,4'-Dimethoxytrityl)-5-[S-(2,4-dinitrophenyl)thio]-2'-deoxyuridin e 3'-O-(2-cyanoethyl N,N'-diisopropylphosphoramidite) was synthesized and incorporated at internal positions in several oligonucleotides using automated DNA synthesis and standard phosphoramidite chemistry. The coupling yield of the analogue was comparable to the coupling yield for a standard phosphoramidite, and no significant differences were observed in the overall yields of the dinitrophenyl-labeled oligonucleotides compared to the corresponding unmodified oligonucleotides. Characterization of the dinitrophenyl-modified oligonucleotides included enzymatic degradation, HPLC chromatography, and gel electrophoresis. Deprotection of the mercaptan group with beta-mercaptoethanol yielded an oligonucleotide containing 5-mercaptodeoxyuridine which was then selectively modified, without purification, by reaction with 5-(iodoacetamido)fluorescein. Incorporation of the dinitrophenyl-modified oligonucleotide into double-stranded DNA was achieved using the polymerase chain reaction. CHaracterization of the dinitrophenyl-labeled product by immunodetection with anti-dinitrophenyl antibodies confirmed the stability of the protecting group to the thermocycling and thus established the use of this thiol-protected mercaptodeoxyuridine phosphoramidite for preparation of site-specifically modified DNA.


Assuntos
Análise Mutacional de DNA/métodos , Desoxiuridina/análogos & derivados , Mutagênese Sítio-Dirigida , Alquilação , Cromatografia Líquida de Alta Pressão , Replicação do DNA , Eletroforese em Gel de Poliacrilamida , Oligonucleotídeos/química , Reação em Cadeia da Polimerase , Endonucleases Específicas para DNA e RNA de Cadeia Simples/metabolismo
10.
EMBO J ; 15(1): 150-61, 1996 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-8598198

RESUMO

The alpha subunit (alpha) of RNA polymerase (RNAP) is critical for assembly of polymerase and positive control of transcription initiation in Escherichia coli. Here, we report that alpha also plays a role in transcription elongation, and this involves a direct interaction between alpha and NusA factor. During in vitro transcription without NusA, alpha interacts with the nascent RNA, as revealed by photocrosslinking. When NusA is present, RNA crosslinks to NusA rather than to alpha. We show that this NusA-RNA interaction is diminished during transcription with an RNAP mutant that lacks the C-terminus of alpha beyond amino acid 235, including the so-called alpha CTD. The absence of alpha CTD also affects NusA's ability to enhance transcription pausing, termination at intrinsic terminators and anti-termination by the phage lambda Q anti-terminator, but not anti-termination by the lambda N anti-terminator. NusA functions are not recovered even when transcription with mutant RNAP is done with excess NusA, a condition which does restore NusA-RNA crosslinking. By affinity chromatography, we show that NusA interacts directly with alpha, and also with beta and beta', but not with mutant alpha. Hence, alpha-NusA interaction is vital for the control of transcript elongation and termination.


Assuntos
Proteínas de Bactérias/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Fatores de Alongamento de Peptídeos , Fatores de Transcrição/metabolismo , Transcrição Gênica , RNA Polimerases Dirigidas por DNA/química , Escherichia coli/enzimologia , Proteínas de Escherichia coli , Ligação Proteica , Moldes Genéticos , Regiões Terminadoras Genéticas , Fatores de Elongação da Transcrição
12.
Protein Expr Purif ; 6(5): 625-31, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8535155

RESUMO

The Escherichia coli transcription factor NusA and the bacteriophage lambda antiterminator Q proteins were expressed as inducible glutathione S-transferase (GST) fusion proteins. The fusion proteins were purified under nondenaturing conditions by affinity chromatography on glutathione agarose. Thrombin cleavage of the glutathione agarose-bound fusion proteins yielded homogeneously pure NusAN+15 (5 mg/g cells) and almost homogeneously pure QN+13 protein (0.7 mg/g cells), where N+x indicates the presence of x additional amino acids at the N-terminus of the protein. The purified NusAN+15 exhibited the same activities as wildtype NusA in enhancement of transcriptional pausing, enhancement of termination at Rho-independent terminators, and enhancement of Q-mediated antitermination in vitro. The QN+13 protein exhibited both anti-pausing and antitermination activities in Q-mediated transcription antitermination. However, the antitermination activity of QN+13 was lost gradually during storage if the thrombin used for cleavage of the GST fusion protein was not removed. This was due to cleavage by thrombin after Arg22 within the Q protein itself, at a noncanonical thrombin cleavage site, so the truncated protein (QN+22) lacked the first 22 amino acids at the N-terminus of Q. The expression vectors described here can be used to rapidly produce large quantities of these proteins, and the truncated Q protein can be used to evaluate the requirement for the N-terminus of Q in antitermination, anti-pausing, interactions with the DNA template (qut site), and interaction with RNA polymerase itself.


Assuntos
Proteínas de Bactérias/biossíntese , Escherichia coli/metabolismo , Glutationa Transferase/genética , Fatores de Alongamento de Peptídeos , Proteínas Recombinantes de Fusão/isolamento & purificação , Fatores de Transcrição/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Bacteriófago lambda/química , Bacteriófago lambda/genética , Sequência de Bases , Cromatografia de Afinidade/métodos , Clonagem Molecular , RNA Polimerases Dirigidas por DNA , Escherichia coli/genética , Proteínas de Escherichia coli , Dados de Sequência Molecular , Desnaturação Proteica , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Sefarose , Trombina/química , Trombina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/isolamento & purificação , Transcrição Gênica , Fatores de Elongação da Transcrição
13.
Australas J Dermatol ; 36(2): 83-5, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7646394

RESUMO

We report a case of Grzybowski's generalized eruptive keratoacanthoma which demonstrates the characteristic features of this rare condition. The recurring nature of the eruption each summer supports the suggestion that UV irradiation may act as a precipitating factor in eruptive keratoacanthoma.


Assuntos
Ceratoacantoma/fisiopatologia , Dermatopatias/fisiopatologia , Humanos , Ceratoacantoma/patologia , Masculino , Pessoa de Meia-Idade , Recidiva , Estações do Ano , Dermatopatias/patologia , Luz Solar/efeitos adversos
14.
Proc Natl Acad Sci U S A ; 92(11): 5012-6, 1995 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-7539140

RESUMO

The effects of NusA on the RNA polymerase contacts made by nucleotides at internal positions in the nascent RNA in Escherichia coli transcription complexes were analyzed by using the photocrosslinking nucleotide analog 5-[(4-azidophenacyl) thio]-UMP. It was placed at nucleotides between +6 and +15 in RNA transcribed from the phage lambda PR' promoter. Crosslinks of analog in these positions in RNAs which contained either 15, 28, 29, or 49 nt were examined. Contacts between the nascent RNA and proteins in the transcription complex were analyzed as the RNA was elongated, by placing the crosslinker nearest the 5' end of the RNA 10, 23, 24, or 44 nt away from the 3' end. The beta or beta' subunit of polymerase, and NusA when added, were contacted by RNA from 15 to 49 nt long. When the upstream crosslinker was 24 nt from the 3" end of the RNA (29-nt RNA), alpha was also contacted in the absence of NusA. The addition of NusA prevented RNA crosslinking to alpha. When the crosslinker was 44 nt from the 3' end (49-nt RNA), alpha crosslinks were still observed, but crosslinks to beta or beta' and NusA were greatly diminished. RNA crosslinking to alpha, and loss of this crosslink when NusA was added, was observed in the presence of NusB, NusE, and NusG and when transcription was carried out in the presence of an E. coli S100 cell extract. Peptide mapping localized the RNA interactions to the C-terminal domain of alpha.


Assuntos
Proteínas de Bactérias/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Proteínas de Escherichia coli , Escherichia coli/metabolismo , RNA Bacteriano/metabolismo , RNA Viral/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Proteínas de Bactérias/isolamento & purificação , Bacteriófago lambda/metabolismo , Sítios de Ligação , Reagentes de Ligações Cruzadas , RNA Polimerases Dirigidas por DNA/isolamento & purificação , Escherichia coli/genética , Substâncias Macromoleculares , Fatores de Alongamento de Peptídeos/metabolismo , Mapeamento de Peptídeos , Regiões Promotoras Genéticas , Ligação Proteica , RNA Bacteriano/biossíntese , RNA Bacteriano/isolamento & purificação , RNA Viral/biossíntese , RNA Viral/isolamento & purificação , Proteínas Ribossômicas/metabolismo , Fatores de Transcrição/isolamento & purificação , Fatores de Elongação da Transcrição
15.
Nucleic Acids Res ; 23(7): 1231-8, 1995 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-7537876

RESUMO

We report a modified synthesis for 5-mercapto-UTP (5-SH-UTP) and its use for analysis of protein-RNA interactions utilizing Escherichia coli and T7 RNA polymerases and yeast RNA polymerases I and III. 5-SH-UTP did not affect transcriptional pausing, Rho-independent termination or recognition of the E. coli transcription complex by NusA. RNA containing 5-SH-UMP did not crosslink to polymerase when irradiation was 302 or 337 nm. Transcription complexes containing RNA substituted with 5-SH-UMP were post-transcriptionally modified to attach a photocross-linking group to thiol-tagged nucleotides in the RNA on the surface of the polymerase of free in solution. The pKa for 5-SH-UTP was determined to be 5.6, so modification of the thiol groups in the RNA with p-azidophenacyl bromide could be carried out at pH 7. Addition of the transcription termination factor Rho, a RNA binding protein, to E. coli transcription complexes resulted in RNA crosslinking to Rho and to the beta and beta' subunits of polymerase. Using 5-SH-UTP, one can distinguish RNA binding domains on the surface of RNA polymerases or other RNA binding proteins from those buried within the protein.


Assuntos
RNA/síntese química , Tionucleotídeos , Uridina Trifosfato/análogos & derivados , Sequência de Bases , Reagentes de Ligações Cruzadas , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Dados de Sequência Molecular , Fotoquímica , Ligação Proteica , RNA/química , RNA/genética , Sondas RNA/síntese química , Sondas RNA/química , Sondas RNA/genética , Processamento Pós-Transcricional do RNA , RNA Bacteriano/química , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , Proteínas de Ligação a RNA/metabolismo , Especificidade por Substrato , Tionucleotídeos/síntese química , Uridina Trifosfato/síntese química
16.
J Mol Biol ; 247(4): 547-58, 1995 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-7536848

RESUMO

We have examined the interaction between NusA and the nascent RNA in Escherichia coli transcription complexes on four different templates. Photocrosslinking CTP and UTP analogs were incorporated internally and at the 3' end of the RNA. Identical templates with and without boxA sequences were compared. We found that NusA did not contact the ten nucleotides nearest to the 3' end of the RNA in complexes containing RNA up to 20 nucleotides long. Longer RNA did crosslink to NusA with all four templates examined, however. We reported that RNA 80 nucleotides long from the bacteriophage T7 A1 promoter substituted in two RNA stem-loops with photocrosslinking UMP analogs did not crosslink to NusA, even though interaction between NusA and the transcription complex were demonstrated. Here, we report that when this same RNA is substituted at CMP residues, it does crosslink to NusA. Templates containing the E. coli ribosomal RNA promoter rrnG P2, with and without a boxA sequence downstream, were compared. Long RNAs from both crosslinked to NusA, and thus boxA RNA sequences are not required for interaction with NusA. NusA did not interact with the free RNA containing boxA once released from the transcription complex, nor did it interact with RNA in a binary complex containing only RNA polymerase and RNA, without the DNA template.


Assuntos
Proteínas de Bactérias/metabolismo , Escherichia coli/genética , Fatores de Alongamento de Peptídeos , RNA Bacteriano/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Bases , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli , Dados de Sequência Molecular , RNA Bacteriano/genética , Transcrição Gênica , Fatores de Elongação da Transcrição
17.
Br J Psychiatry ; 165(6): 802-7, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7881783

RESUMO

BACKGROUND: A multi-dimensional approach was used to examine coping in chronic pain. The following hypotheses were tested: (a) patients who cope maladaptively also cope generally in a similar way; (b) patients' maladaptive coping is associated with childhood adversity. METHOD: Cross-sectional and retrospective data were collected from 68 consecutive patients (aged 18-70) at a pain clinic where their disease was non-systemic and the pain had lasted for at least three months. Sixty-one patients were interviewed using the Structured Clinical Interview for DSM-III-R, and the Measure of Parental Care in Childhood. All patients completed questionnaires on their pain and personality. RESULTS: Two coping styles emerged from factor analysis. One was associated with chronicity, psychiatric morbidity, harm avoidance, immature defence style and reporting parental indifference. CONCLUSION: Patients may be predisposed to cope maladaptively after the experience of parental indifference in early life. Such coping is likely to reflect more general patterns.


Assuntos
Adaptação Psicológica , Dor/psicologia , Adolescente , Adulto , Idoso , Doença Crônica , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Inquéritos e Questionários
19.
J Bacteriol ; 176(6): 1787-9, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7510675

RESUMO

A conformational change in Escherichia coli RNA polymerase induced by NusA was detected by utilizing photocrosslinking. A change in the binding site for the 3' end of the RNA occurred, and NusA increased interactions of the RNA with the beta subunit of the polymerase. NusA was not contacted by the 3' end of the RNA.


Assuntos
Proteínas de Bactérias/fisiologia , RNA Polimerases Dirigidas por DNA/química , Escherichia coli/enzimologia , Fatores de Alongamento de Peptídeos , RNA Bacteriano/química , Fatores de Transcrição/fisiologia , Sequência de Bases , Sítios de Ligação , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/química , Escherichia coli/metabolismo , Proteínas de Escherichia coli , Dados de Sequência Molecular , Conformação Proteica , RNA Bacteriano/metabolismo , Fatores de Elongação da Transcrição
20.
Pharmazie ; 48(11): 808-11, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8295910

RESUMO

Some new substituted thiazolidinones, thioimidazolidinones and thiazolines have been synthesized from N1-substituted N2-(4-hydroxy-7-methyl-5H-furo[3,2-g] [1]benzopyran-5-on-9-yl)thioureas and monochloroacetic acid or alpha-halocarbonyl compounds. Some representative examples were tested for their anticonvulsant and antimicrobial activities.


Assuntos
Anti-Infecciosos/síntese química , Anticonvulsivantes/síntese química , Cromonas/síntese química , Animais , Antibacterianos , Anti-Infecciosos/farmacologia , Anticonvulsivantes/farmacologia , Bactérias/efeitos dos fármacos , Cromonas/farmacologia , Fungos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Pentilenotetrazol/antagonistas & inibidores , Espectrofotometria Infravermelho
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