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1.
Musculoskelet Surg ; 108(2): 183-194, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38462596

RESUMO

PURPOSE: To demonstrate how the use of adjunctive Computed Tomography (CT) can modify diagnosis, treatment options, and operative planning of ankle fractures in comparison with conventional radiographs (CR) in isolation. MATERIALS AND METHODS: A total of 53 patients diagnosed with an ankle fracture between 2011 and 2016, were assessed with CT and CR. Evaluations of the fractures using CR in isolation and CR combined with CT were compared using different readers. Fractures were assessed in terms of type, displacement, size, associated injuries, treatment, patient position and surgical planning. RESULTS: The medial malleolus fractures characteristics (posteromedial fragment and anterior colliculus), the presence of posterior malleolus fracture and its characteristics (displacement, size, posteromedial or posterolateral segment) (ps < 0.042), syndesmosis injury (p < 0.001), and the absence of deltoid ligament lesion (p < 0.001), were more evident with the combination of CT and radiographs. There was an increase in operative indication (p = 0.007), prone positioning (p = 0.002), posterior malleolus surgical treatment (p < 0.001), posterolateral approach for the lateral malleolus (p = 0.003), and syndesmosis fixation (p = 0.020) with the association of CT and CR, among all groups of expertise, with a high interobserver reliability (> 0.75). CONCLUSIONS: The CR may fail to demonstrate subtle lesions, such as posterior malleolus fractures and syndesmotic injuries. The CT evaluation increases the diagnostic precision and improves the quality of information the surgeon receives, what might positively affect patient care. LEVEL OF EVIDENCE III: Retrospective Comparative Study.


Assuntos
Fraturas do Tornozelo , Tomografia Computadorizada por Raios X , Humanos , Fraturas do Tornozelo/diagnóstico por imagem , Fraturas do Tornozelo/cirurgia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Estudos Retrospectivos , Idoso , Adulto Jovem , Fixação Interna de Fraturas/métodos
2.
In. Sala, Arnaldo; Seixas, Paulo Henrique D'Ângelo. I Mostra SES/SP 2007: experiências inovadoras na gestão da saúde no Estado de São Paulo. São Paulo, SES/SP, 2008. p.91-95, tab, graf.
Monografia em Português | LILACS, Sec. Est. Saúde SP, SESSP-CTDPROD, Sec. Est. Saúde SP | ID: lil-503595

RESUMO

A avaliação de desempenho passou a ser empregada nas empresas com o objetivo de alcançar um desenvolvimento maior do homem, das relações humanas e do trabalho desenvolvido. É uma técnica utilizada para obter informações sobre o comportamento profissional do funcionário. Clientes e usuários estão cada vez mais exigentes com os produtos e serviços de que dispõem, e a questão da qualidade tem apresentado crescente preocupação em todo o mundo. A nova consciência de qualidade dos produtos e serviços concede mais valorização aos esforços do indivíduo, considerando-se que as pessoas envolvidaS são fundamentais, pois a qualidade depende do trabalho individual ou em grupo. A preocupação dos hospitais, atualmente, pela busca da qualidade dos serviços vem exigindo de seus profissionais e colaboradores uma nova postura...


Assuntos
Análise Institucional , Avaliação de Desempenho Profissional , Planejamento Estratégico
3.
J Pept Res ; 56(3): 147-56, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11007271

RESUMO

The amino acid sequence of osteogenic growth peptide (OGP) consists of 14 residues identical to the C-terminal tail of histone H4. Native and synthetic OGP are mitogenic to osteoblastic and fibroblastic cells and enhance osteogenesis and hematopoiesis in vivo. The C-terminal truncated pentapeptide of OGP, H-Tyr-Gly-Phe-Gly-Gly-OH [OGP(10-14)], is a naturally occurring osteoblastic mitogen, equipotent to OGP. The present study assesses the role of individual amino acid residues and side chains in the OGP(10-14) mitogenic activity which showed a very high correlation between osteoblastic and fibroblastic cell cultures. Truncation of either Tyr10 or its replacement by Ala or D-Ala resulted in substantial, but not complete, loss of activity. Nevertheless, only a small loss of activity was observed following removal of the Tyr10 amino group. No further loss occurred consequent to the monoiodination of desaminoTyr10 on meta-position. However, a marked decrease in proliferative activity followed removal of the Tyr10 phenolic or the Phe12 aromatic group. Loss of activity of a similar magnitude also occurred subsequent to replacing Gly11 with L- or D-Ala. Approximately 50% loss of mitogenic activity occurred subsequent to truncation of Gly14 or blocking the C-terminal group as the methyl ester. All other modifications of the C-terminus and L- or D-Ala substitution of Gly13 resulted in 70-97% decrease in activity. Collectively, these data suggest that the integrity of the pharmacophores presented by Tyr and Phe side chains, as well as the Gly residues at the C-terminus, are important for optimal bioactivity of OGP(10-14).


Assuntos
Substâncias de Crescimento/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular , Oligopeptídeos/farmacologia , Peptídeos/farmacologia , Sequência de Aminoácidos , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Substâncias de Crescimento/química , Histonas , Camundongos , Mitógenos/farmacologia , Dados de Sequência Molecular , Oligopeptídeos/química , Osteoblastos/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Peptídeos/química , Ligação Proteica , Relação Estrutura-Atividade
4.
Int Surg ; 85(4): 339-43, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11589604

RESUMO

Psoas abscess (PA) is an infrequent clinical entity and presents diagnostic and therapeutic challenges. Six cases are reported concerning diagnostic and therapeutic considerations. Clinical diagnosis is difficult because of non-specific symptoms. The primary psoas abscess has no definite etiology and is spread by hematogeneous route from a distant occult site. The PA can also be secondary to gastrointestinal pathology through direct infection of adjacent structures. The most common causes are Crohn's disease, appendicitis, diverticulitis and carcinoma. Routine laboratory evaluation is seldom useful for localizing the disease process. Conventional radiological techniques are often unhelpful. Modern imaging diagnosis techniques such as ultrasound and computerized tomography have allowed for a refinement in both the etiologic diagnosis and the treatment by means of CT-guided or ultrasound-guided percutaneous drainage of the abscess, thus avoiding surgical drainage in many cases. Immediately on diagnosis of PA prompt treatment is necessary. Percutaneous drainage should be performed whenever possible and in case of failure, surgical drainage should be practiced as well as intestinal resection, whenever indicated.


Assuntos
Antibacterianos , Quimioterapia Combinada/administração & dosagem , Infecções por Klebsiella/diagnóstico , Abscesso do Psoas/diagnóstico , Abscesso do Psoas/terapia , Infecções Estafilocócicas/diagnóstico , Adolescente , Adulto , Idoso , Brasil , Terapia Combinada , Drenagem/métodos , Feminino , Seguimentos , Humanos , Infecções por Klebsiella/terapia , Masculino , Infecções Estafilocócicas/terapia , Resultado do Tratamento
5.
Rev. Assoc. Med. Bras. (1992) ; 45(4): 317-22, out.-dez. 1999. tab
Artigo em Português | LILACS | ID: lil-247424

RESUMO

Objetivo. Estudo retrospectivo dos resultados tardios dos pacientes submetidos a miotomia e fundoplicatura para o tratamento do megaesôfago. Casuística e Métodos. Foram estudados 83 pacientes com seguimento de um a 186 meses (média de 40,0 + 47,4 meses). A fundoplicatura em três planos, proposta por Pinotti, foi realizada em 15,7 por cento dos doentes e a fundoplicatura parcial posterior em 83,1 por cento. A queixa pré-operatória principal foi disfagia, seguida de regurgitação e perda ponderal. A etiologia chagásica pode ser comprovada em 72,3 por cento dos doentes, através de teste sorológico. Resultados. No seguimento, 55,4 por cento dos doentes estavam assintomáticos, 34,9 por cento queixavam-se de disfagia esporádica, 14,4 por cento de pirose, 8,4 por cento de regurgitação e 2,4 por cento de disfagia igual pré-operatória, sendo esses últimos pré-operados, com melhora da sintomatologia. Refluxo gastro-esofágico foi constatado em 8,4 por cento dos doentes. Outras complicações tardias foram: hérnia paraesofágica, deslizamento da fundoplicatura, esôfago de Barrett e neoplasia do esôfago. Conlcusões. Os autores salientaram a necessidade de acompanhamento clínico e endoscópico perene dos doentes, mesmo operados, devido à possibilidade de complicações tardias, em especial o câncer. Concluem por bons resultados tardios em relação à disfagia. Propõem, como alternativa à esofagectomia, a operação de Heller em pacientes portadores de megaesôfago para grau IV com más condições clínicas, que não suportariam uma cirurgia de maior porte.


Assuntos
Adulto , Pessoa de Meia-Idade , Feminino , Humanos , Adolescente , Acalasia Esofágica/cirurgia , Fundoplicatura , Laparoscopia/métodos , Seguimentos , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
6.
J Pept Res ; 54(5): 408-14, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10563506

RESUMO

The osteogenic growth peptide (OGP) is a 14-amino acid stromal cell mitogen that stimulates in vivo osteogenesis and hematopoiesis. In the blood circulation and cell culture conditioned medium immunoreactive OGP (irOGP), identified using antibodies raised against the OGP C-terminal region, presents free and bound forms. The bound form consists entirely of the full length peptide. The present study was designed to investigate the identity of free irOGP under nondenaturing conditions. Fresh human serum and culture medium conditioned with murine osteoblastic MC3T3 E1 cells were fractionated using ultrafiltration (3000 molecular weight cut-off). Hydrophobic chromatography of the ultrafiltrate, immunoscreening of chromatographic fractions with antibodies directed against the OGP C-terminal region and amino acid sequencing of immunoreactive peaks demonstrated the presence of two mitogens, the full length OGP and a C-terminal truncated form, OGP(10-14). The OGP(10-14) derived from both serum and conditioned medium, as well as the synthetic pentapeptide [sOGP(10-14)], shared the in vitro OGP proliferative activity. However, in a competitive binding assay, devised to assess the OGP-OGP binding protein (OGPBP) complex formation, sOGP(10-14) failed to compete out radiolabeled OGP from the complex. It is concluded that OGP(10-14) is a naturally occurring human and murine mitogen. In addition, the data suggests that the OGP(10-14) is generated from OGP by proteolytic cleavage upon dissociation of the OGP-OGPBP complexes.


Assuntos
Substâncias de Crescimento/química , Peptídeos e Proteínas de Sinalização Intercelular , Fragmentos de Peptídeos/isolamento & purificação , Peptídeos/química , Animais , Ligação Competitiva , Divisão Celular , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Meios de Cultivo Condicionados/química , Substâncias de Crescimento/sangue , Histonas , Humanos , Radioisótopos do Iodo , Camundongos , Osteoblastos , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Ligação Proteica , Análise de Sequência
7.
Rev Assoc Med Bras (1992) ; 45(4): 317-22, 1999.
Artigo em Português | MEDLINE | ID: mdl-10752238

RESUMO

BACKGROUND: Retrospective study of the late results of the Heller's cardiomyotomy and fundoplication for the treatment of the megaesophagus. MATERIAL AND METHODS: Were studied 83 patients with a follow-up from one to 186 months (average 40.0 +/- 47.4 months). The fundoplications used were in three plans in 15.7% and posterior in 83.1%. The main pre-operatory complain was dysphagia followed by regurgitation and loss of weight. Chagas, Disease as the etiology was confirmed in 72.3% of the patients. RESULTS: In the follow-up 55.4% of the patients were assymptomatic, 34.9% complained of sporadic dysphagia, 14.4% of heartburn, 8.4% of regurgitation and 2.4% did not changed the dysphagia, these being re-operated and had improvement the symptoms. Gastro-esophageal reflux was noted in 8.4% of the patients. Other late complications were par-esophageal hernia, sliping of the fundoplication, Barrett esophagus and cancer. CONCLUSIONS: The necessity of a long-term clinical and endoscopical follow-up, even after surgery, owing to the possibility of late complications, especially cancer was emphasized. The late results are good in relation to the dysphagia. Myotomy is proposed as an alternative to patients with advanced megaesophagus with bad clinical conditions who can not be submitted to an esophagectomy.


Assuntos
Acalasia Esofágica/cirurgia , Fundoplicatura , Laparoscopia/métodos , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
8.
Sao Paulo Med J ; 116(4): 1781-3, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9951750

RESUMO

The authors report a case of a 25 year old Brazilian man with a history of crampy abdominal pain in the left iliac fossa for 2 weeks, abdominal distention, mucous diarrhea and anorexia. The patient presented signs of hemodynamic instability and a hard mass palpated in the left iliac fossa presented peritoneal irritation. At laparotomy, fecal peritonitis and a punched-out perforation of the midsigmoid colon were found. A left hemicolectomy was performed with terminal colostomy. Specimen examination revealed a thickened rectosigmoid wall, narrow lumen and multiple mucosal polyps. Microscopically, chronic granulomatous colitis with Schistosoma mansoni eggs confirmed the etiology. To the authors' knowledge, this is the first case of obstruction complicated with perforation due to mansoni schistosomiasis reported in the literature.


Assuntos
Doenças do Colo/complicações , Obstrução Intestinal/complicações , Perfuração Intestinal/etiologia , Esquistossomose mansoni/complicações , Adulto , Animais , Humanos , Obstrução Intestinal/parasitologia , Masculino , Schistosoma mansoni/isolamento & purificação , Doenças do Colo Sigmoide/etiologia , Doenças do Colo Sigmoide/parasitologia
9.
Biochemistry ; 36(48): 14883-8, 1997 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-9398211

RESUMO

The osteogenic growth peptide (OGP) is a 14mer mitogen of osteoblastic and fibroblastic cells. Physiologically, OGP is present in high abundance in human and other mammalian sera. Most of the serum OGP is complexed noncovalently to heat sensitive, high molecular weight OGP-binding proteins (OGPBPs). Changes in serum OGP levels that follow bone marrow ablation and the low doses of exogenous OGP required for the stimulation of bone formation suggest a regulatory role for the OGPBPs. In the present work, the OGP binding activity was monitored by competitive binding to [3-125I(Tyr10)]-sOGP and the corresponding complexes were demonstrated on nondenaturing cathodic polyacrylamide gel electrophoresis. We show that OGP binds to both native and activated human plasma alpha 2-macroglobulin (alpha 2M). alpha 2M was also immunoidentified in reduced and nonreduced SDS-polyacrylamide gel electrophoresis of OGP-affinity purified plasma-derived proteins. Immunoreactive OGP was detected in commercial preparations of both forms of alpha 2M; OGP was purified to homogeneity from the commercial preparation of activated alpha 2M. In MC3T3 E1 cells, native alpha 2M, at concentrations < 50 ng/mL, had a substantially increased mitogenic effect in the presence of synthetic, native-like, OGP (sOGP). Similar amounts of activated alpha 2M inhibited the sOGP proliferative effect. These results suggest that the native alpha 2M enhances the immediate availability of OGP to its target cells. Activated alpha 2M may participate in the removal of OGP from the system.


Assuntos
Substâncias de Crescimento/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Osteogênese , Peptídeos/metabolismo , alfa-Macroglobulinas/metabolismo , Substâncias de Crescimento/farmacologia , Histonas , Humanos , Mitógenos , Osteoblastos/efeitos dos fármacos , Peptídeos/farmacologia , Ligação Proteica , alfa-Macroglobulinas/farmacologia
10.
Mol Microbiol ; 24(6): 1303-10, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9218777

RESUMO

Rapid proteolysis plays an important role in regulation of gene expression. Proteolysis of the phage lambda CII transcriptional activator plays a key role in the lysis-lysogeny decision by phage lambda. Here we demonstrate that the E. coli ATP-dependent protease FtsH, the product of the host ftsH/hflB gene, is responsible for the rapid proteolysis of the CII protein. FtsH was found previously to degrade the heat-shock transcription factor sigma32. Proteolysis of sigma32 requires, in vivo, the presence of the DnaK-DnaJ-GrpE chaperone machine. Neither DnaK-DnaJ-GrpE nor GroEL-GroES chaperone machines are required for proteolysis of CII in vivo. Purified FtsH carries out specific ATP-dependent proteolysis of CII in vitro. The degradation of CII is at least 10-fold faster than that of sigma32. Electron microscopy revealed that purified FtsH forms ring-shaped structures with a diameter of 6-7 nm.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Bactérias/metabolismo , Bacteriófago lambda , Escherichia coli/enzimologia , Proteínas de Membrana/metabolismo , Fatores de Transcrição/metabolismo , Proteases Dependentes de ATP , Adenosina Trifosfatases/ultraestrutura , Proteínas de Bactérias/ultraestrutura , Endopeptidases/metabolismo , Escherichia coli/virologia , Proteínas de Escherichia coli , Proteínas de Membrana/ultraestrutura , Proteínas Virais
11.
J Inorg Biochem ; 58(2): 79-88, 1995 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-7769384

RESUMO

A new series of platinum-anthraquinone complexes of the type cis-PtLL'Cl2 [where L is the monodentate AQ-NH-(CH2)n-NH2 and L' = NH3 or LL' is the bidentate ligand AQ-NH-(CH2)n. NH-(CH2)2-NH2] in which the anthraquinone is linked to the diaminedichloroplatinum (II) moiety through position 2 was prepared and screened in vitro for antileukemic activity against P388 cells. All ligands were characterized by 1H and 13C NMR spectroscopy and all complexes by 195Pt NMR. The platinum complexes of anthraquinones which are modified in position 2 are significantly less potent than their analogs which are substituted in position 1. The activity of the complexes is either equal to or lower than the activity of the free ligands themselves. In the attempt to prepare AQ-NH-(CH2)4-NH-(CH2)2-NH2, a new compound, 2-(N-pyrrolidine)anthraquinone, was obtained and its structure was determined by x-ray crystallography. It crystallized in the monoclinic system in the space group P2(1)/c. The unit cell parameters are a = 9.595(1), b = 12.537(2), c = 11.461(1) A, beta = 94.14(2) degrees, V = 1375(1) A3, and z = 4.


Assuntos
Antraquinonas/síntese química , Antineoplásicos/síntese química , Compostos de Platina/síntese química , Animais , Antraquinonas/química , Antraquinonas/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Cisplatino , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Leucemia P388/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Camundongos , Compostos de Platina/química , Compostos de Platina/farmacologia , Células Tumorais Cultivadas
12.
Biochim Biophys Acta ; 1178(3): 273-80, 1993 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-8364043

RESUMO

We have recently reported the discovery of a 14-amino-acid osteogenic growth peptide (OGP). In vivo OGP increases bone formation and trabecular bone density. Physiologically it is found in serum complexed to an OGP binding protein (OGPBP). In vitro OGP has a biphasic effect on osteoblastic MC 3T3 E1 and fibroblastic NIH 3T3 cell proliferation; at low concentrations (0.01-1.0 and 1.0-100.0 pM, respectively) it is highly stimulatory with an inhibition at higher doses. To assess possibilities of labeling synthetic OGP to obtain radio- or fluorescent ligands, OGP analogues were extended at the N- or C-termini with Cys or Cys(S-NEtSucc) or the OGP Tyr-10 replaced by 3-I(Tyr). All analogues with N-terminal modifications, as well as the [Cys15]OGP-NH2 retained the OGP-like dose-dependent effect on proliferation of the MC 3T3 E1 and NIH 3T3 cells, although the magnitude of stimulation was lower, approx. 2/3 that of the native-like synthetic OGP. The [Cys15(S-NEtSucc)]OGP-NH2 and [3-I(Tyr10)]OGP shared only the inhibitory activity of OGP. This suppression is further shared by a number of other positively and negatively net charged, but not net neutral, peptides. Both N-terminal-modified analogues displayed a decreased binding activity to the OGPBP. All analogues except reverse OGP, [3-I(Tyr10)]OGP and [Cys15(S-NEtSucc)]OGP-NH2 reacted with anti-OGP antibodies. These data are not only important for labeling purposes but suggest a respective role for the OGP N-and C-terminal regions in binding to the OGPBP and putative OGP receptor. It appears that the OGP proliferative activity represents the net effect of stimulation specific to the OGP structure and nonspecific inhibition associated with the peptide's high positive net charge.


Assuntos
Substâncias de Crescimento/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular , Mitógenos/farmacologia , Peptídeos/farmacologia , Células 3T3/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Substâncias de Crescimento/síntese química , Substâncias de Crescimento/química , Histonas , Radioisótopos do Iodo , Camundongos , Dados de Sequência Molecular , Osteoblastos , Peptídeos/síntese química , Peptídeos/química , Ligação Proteica
13.
Nucleic Acids Res ; 21(4): 993-8, 1993 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-8451199

RESUMO

The cell cycle regulation of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH)/uracil DNA glycosylase (UDG) gene was examined in normal human cells. Steady state RNA levels were monitored by Northern blot analysis using a plasmid (pChug 20.1) which contained the 1.3 kb GAPDH/UDG cDNA. The biosynthesis of the 37 kDa GAPDH/UDG protein was determined using an anti-human placental GAPDH/UDG monoclonal antibody to immunoprecipitate the radiolabeled protein. Increases in steady state GAPDH/UDG mRNA levels were cell cycle specific. A biphasic pattern was observed resulting in a 19-fold increase in the amount of GAPDH/UDG mRNA. The biosynthesis of the 37 kDa GAPDH/UDG protein displayed a similar biphasic regulation with a 7-fold increase. Pulse-chase experiments revealed a remarkably short half life of less than 1 hr. for the newly synthesized 37 kDa protein, comparable to that previously documented for a number of oncogenes. GAPDH/UDG mRNA levels were markedly reduced at 24 hr. when DNA synthesis was maximal. These results define the GAPDH/UDG gene as cell cycle regulated with a characteristic temporal sequence of expression in relation to DNA synthesis. The cell cycle synthesis of a labile 37 kDa monomer suggests a possible regulatory function for this multidimensional protein. Further, modulation of the GAPDH/UDG gene in the cell cycle may preclude its use as a reporter gene when the proliferative state of the cell is not kept constant.


Assuntos
Ciclo Celular/genética , DNA Glicosilases , Gliceraldeído-3-Fosfato Desidrogenases/genética , N-Glicosil Hidrolases/genética , Células Cultivadas , Regulação Enzimológica da Expressão Gênica , Gliceraldeído-3-Fosfato Desidrogenases/biossíntese , Humanos , Dados de Sequência Molecular , Complexos Multienzimáticos/biossíntese , Complexos Multienzimáticos/genética , N-Glicosil Hidrolases/biossíntese , RNA Mensageiro/metabolismo , Fase S , Uracila-DNA Glicosidase
14.
Opt Lett ; 18(9): 699-701, 1993 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19802244

RESUMO

A theoretical study of the nonlinear propagation of picosecond chirped pulses in single-mode fibers is presented. We show that, under appropriate conditions, spectral narrowing-rather than broadening, as is generally believed-is induced, owing to the interplay of self-phase-modulation and dispersion. For downchirped pulses at a wavelength of 0.9 microm and a peak power as low as 0.1 W, substantial spectral narrowing occurs.

15.
Carcinogenesis ; 13(11): 2127-32, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1423884

RESUMO

The relationship between the proliferative dependent expression of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH)/uracil DNA glycosylase (UDG) gene and the induction of uracil DNA glycosylase activity was examined in human cells. Three different cell types were studied to determine whether the growth-dependent regulation of this multifunctional gene was a common characteristic of human cells. These included WI-38 normal embryonic lung fibroblasts, a Japanese Bloom's syndrome non-transformed skin fibroblast cell strain (GM-05289) and a lymphoblastoid cell line transformed by the Epstein-Barr virus. The Japanese Bloom's syndrome cells displayed the altered immunoreactivity with marker monoclonal antibody 40.10.09 which characterizes cells from this human genetic disorder. In noncycling human cells Northern blot analysis using a plasmid (pChug 20.1) which contained the human GAPDH/UDG cDNA revealed a single 1.6 kb transcript. In each case, the expression of this gene was increased during cell proliferation. This increase in GAPDH/UDG gene expression was identical to that observed for UDG enzyme activity. Further, using anti-human UDG monoclonal antibodies, there was a growth-dependent rise in immunoreactivity suggesting an increase in the level of antigenic protein. These results demonstrate that: (i) the expression of the GAPDH/UDG gene was dependent on the proliferative state of the cell; and (ii) a correlation existed between the transcription of this gene and the level of uracil DNA glycosylase enzyme activity.


Assuntos
Divisão Celular , DNA Glicosilases , Reparo do DNA , Regulação Enzimológica da Expressão Gênica , Gliceraldeído-3-Fosfato Desidrogenases/genética , N-Glicosil Hidrolases/genética , Northern Blotting , Transformação Celular Viral , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Fibroblastos/enzimologia , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Humanos , N-Glicosil Hidrolases/metabolismo , Transcrição Gênica , Uracila-DNA Glicosidase
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