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1.
J Nutr Health Aging ; 22(6): 695-699, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29806858

RESUMO

OBJECTIVES: The purpose of this study was to assess the relationship between economic security and self-rated health for elderly Japanese residents living alone. DESIGN: A secondary analysis of a cross-sectional study. SETTING: N City, H. Prefecture, Japan. PARTICIPANTS: Survey questionnaires were distributed to 2,985 elderly residents living alone, aged ≥70 years, of which, 1,939 (65.0%) were returned and treated as valid responses. MEASUREMENTS: The survey included questions about gender, age, number of years spent in N City, self-rated health, economic security, number of years spent living alone, reason for living alone, life satisfaction, cooking frequency, frequency of seeing a doctor, long-term care service usage, as well as whether they enjoyed their lives, participated in social organizations. RESULTS: Of the respondents, 1,563 (80.6%) reported that they were economically secure, and 376 (19.4%) responded that they were insecure. The odds ratio predicting poor self-rated health for the economically insecure participants was significantly high (odds ratio: 3.19, 95%, Confidence Interval (CI): 2.53-4.02, and P < 0.001). Similarly, the adjusted odds ratio for poor self-rated health was significantly high for the economically insecure participants in multivariate analyses controlling for factors such as age, gender, cooking frequency, and social participation (adjusted odds ratio: 2.21, 95%, CI: 1.70-2.88, and P < 0.001). Furthermore, a similar trend was observed in stratified analyses based on gender and age groups. CONCLUSION: Economic security predicted self-rated health independently of confounders, including social participation and cooking frequency, among the elderly Japanese living alone in communities.


Assuntos
Status Econômico/estatística & dados numéricos , Nível de Saúde , Qualidade de Vida/psicologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Japão , Masculino , Razão de Chances , Características de Residência/estatística & dados numéricos , Autorrelato/estatística & dados numéricos , Participação Social/psicologia , Inquéritos e Questionários
2.
Chem Commun (Camb) ; 51(26): 5717-20, 2015 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-25719744

RESUMO

Visible-light-controlled polymerization was achieved by a bichromophoric organopalladium catalyst which possesses a naphthyl-substituted cyclometallated Ir(III) light-absorbing moiety. The complex was highly active toward styrene polymerization upon visible-light irradiation, and its photoactivity toward polymerization and dimerization was switchable. On the basis of the switching activity, controlled copolymerization of styrene and vinyl ether was achieved upon photo-irradiation to give the corresponding copolymers.

3.
Oral Dis ; 20(4): 404-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23750917

RESUMO

OBJECTIVE: Masticatory muscle tendon-aponeurosis hyperplasia is a new disease entity associated with limited mouth opening. In this study, we analyzed the microstructural characteristics of muscles and tendons in masticatory muscle tendon-aponeurosis hyperplasia by electron microscopy and energy-dispersive X-ray analysis to determine the elemental composition. METHODS: Histological analysis was performed to detect the calcification. Transmission electron microscopy and scanning electron microscopy were conducted to clarify the microstructural characteristics of muscles and tendons. Energy-dispersive X-ray microanalysis was performed to identify the distribution of elements. RESULTS: Mineralized nodules were observed in tendon tissues of masticatory muscle tendon-aponeurosis hyperplasia as compared with facial deformity. Electron microscopy revealed that the muscle and tendon tissues in masticatory muscle tendon-aponeurosis hyperplasia showed degenerative changes and distinctive histological findings as compared with tissues in facial deformity. We found that Ca, P, and Si were detected only in masticatory muscle tendon-aponeurosis hyperplasia. CONCLUSION: We demonstrated that masticatory muscle tendon-aponeurosis hyperplasia exhibits heterotopic calcification in tendon tissues.


Assuntos
Calcinose/patologia , Músculos da Mastigação/patologia , Doenças Musculares/patologia , Tendões/patologia , Adulto , Calcinose/complicações , Feminino , Humanos , Hiperplasia/complicações , Doenças Musculares/complicações
4.
Reprod Domest Anim ; 41(2): 180-3, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16519726

RESUMO

The aim of this study was to investigate whether the skim milk progesterone concentrations at artificial insemination (AI) and day of rise of post-ovulatory progesterone concentration thereafter affect the conception and embryonic death rates in repeat-breeding cows. Milk samples were obtained from 96 repeat-breeding cows that failed to conceive to three or more AIs. The samples were taken from the cows at the day of AI and three times/week until day 45 post-AI. Skim milk was obtained after centrifugation and used for progesterone assay. The cows with a progesterone concentration more than 0.5 ng/ml at AI showed a significantly higher incidence of late embryonic death than those having a progesterone concentration<0.5 ng/ml at AI (p<0.01). As the progesterone level at insemination rose, conception rate declined. A negative correlation was shown between conception rate and skim milk progesterone level at AI. Of 56 cows showing a rise of progesterone to 1 ng/ml or more within 6 days after AI, 28 cows (50%) conceived. On the contrary, only eight of 39 cows (20.5%) conceived when the progesterone rose up to 1 ng/ml after day 6 post-AI. We concluded that increased progesterone concentration at the time of AI and delayed rise of progesterone post-AI might lead to decrease in fertility in repeat-breeding cows.


Assuntos
Bovinos/fisiologia , Fertilidade/fisiologia , Inseminação Artificial/veterinária , Leite/química , Progesterona/análise , Animais , Cruzamento , Bovinos/metabolismo , Feminino , Inseminação Artificial/métodos , Gravidez , Resultado da Gravidez/veterinária , Taxa de Gravidez
5.
Anim Reprod Sci ; 90(3-4): 211-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16298272

RESUMO

The present study was undertaken to examine whether pregnancy diagnosis was possible by measuring fecal progesterone concentrations in beef and dairy heifers and beef cows. Rectal fecal samples collected on days 18-24 after insemination or days 11-17 after embryo transfer were mixed with methanol and shaken for preparation of a fecal solution. After centrifugation, the supernatant was extracted with petroleum ether followed by an enzyme immunoassay for progesterone. All pregnant animals showed fecal progesterone concentrations greater than 50 ng/g of fecal material on days 18-24 after AI or estrus. In non-pregnant animals, however, the fecal progesterone concentrations ranged widely from 5 to 180 ng/g of fecal material. In non-pregnant cattle, the percentage of cattle with <50 ng progesterone/g of fecal material compared with the total number was 37-60% on days 18-20, whereas the percentages increased more than 70% to a maximum of 78.1% on day 23. When 50 ng/g was considered as the cut-off value, the sensitivity and specificity of positive pregnancy tests were less than 70% on days 21-24, and 100% for negative pregnancy tests on days 18-24. There were significant differences in the mean fecal progesterone concentrations between pregnant and non-pregnant cattle on days 19-24. These results suggest that feces can be utilized to substitute for plasma and milk to measure progesterone for the purpose of pregnancy diagnosis in heifers and cows.


Assuntos
Bovinos , Fezes/química , Testes de Gravidez/veterinária , Progesterona/análise , Animais , Transferência Embrionária/veterinária , Feminino , Inseminação Artificial/veterinária , Gravidez , Progesterona/sangue , Sensibilidade e Especificidade , Fatores de Tempo
6.
Histol Histopathol ; 20(3): 761-8, 2005 07.
Artigo em Inglês | MEDLINE | ID: mdl-15944925

RESUMO

Senescence Marker Protein-30 (SMP30) is a calcium-regulating protein that decreases in an androgen-independent manner as aging occurs. An enzyme-labeled antibody technique has demonstrated that SMP30 localized to the ducts (granular, intercalated, and striated ducts) of mouse submandibular glands. Immunoelectronmicroscopy demonstrated that the granular duct cells were strongly positive for SMP30, but that pillar cells in the granular duct were negative for the protein. In SMP30-knockout (KO) mice, the granular ducts were smaller in diameter. Swelling of mitochondria in the granular duct cells was observed; however, this phenomenon was not observed in the pillar cells. After administration of alpha-isoproterenol, a beta-adrenergic stimulant, a large numbers of small secretory granules were present in the granular duct cells and an expansion of the rough endoplasmic reticulum in SMP30-wild type (WT) mice; in contrast, little change was observed in SMP30-KO mice. These results suggest that SMP30 may be closely related to a signal transduction pathway in the granular duct cells of submandibular glands.


Assuntos
Proteínas de Ligação ao Cálcio/análise , Glândula Submandibular/química , Animais , Proteínas de Ligação ao Cálcio/genética , Feminino , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular , Isoproterenol/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Imunoeletrônica , Glândula Submandibular/efeitos dos fármacos , Glândula Submandibular/ultraestrutura , Sulfotransferases
7.
Appl Microbiol Biotechnol ; 65(5): 583-92, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15248038

RESUMO

Arthrobacter globiformis T6 is unique in that it produces an enzyme yielding only isomaltose from dextran. In the present study, the organism was re-identified and its classification as a new species of the genus Arthrobacter, A. dextranlyticum, was proposed. The high G+C gene (66.8 mol%) for the isomalto-dextranase was sequenced. The deduced amino acid sequence, with a calculated molecular mass of 65,993 Da (603 amino acids), was confirmed by nanoscale capillary liquid chromatography coupled to tandem mass spectrometry, which covered 71.1% of the amino acid residues of the entire sequence. The enzyme was grouped into glycoside hydrolase family 27, and the C-terminal domain has homology to carbohydrate-binding module family 6. Hyper-exoproduction of the recombinant enzyme was achieved at a level corresponding to approximately 4.6 g l(-1) of culture broth when proteases-deficient Bacillus subtilis cells were used as the host. The purified enzyme (65.5 kDa) had an optimal pH and temperature for activity of 3.5 and 60 degrees C, respectively. It was crystallized using the sitting-drop vapor-diffusion method at 293 K.


Assuntos
Arthrobacter/enzimologia , Bacillus subtilis/genética , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Peptídeo Hidrolases/genética , Sequência de Aminoácidos , Arthrobacter/classificação , Arthrobacter/genética , Bacillus subtilis/enzimologia , Bacillus subtilis/metabolismo , Composição de Bases , Sequência de Bases , Clonagem Molecular , Cristalização , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , Estabilidade Enzimática , Deleção de Genes , Expressão Gênica , Genes Bacterianos , Genes de RNAr/genética , Glicosídeo Hidrolases/química , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Peso Molecular , Filogenia , Estrutura Terciária de Proteína , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA , Temperatura
8.
Histol Histopathol ; 19(3): 735-42, 2004 07.
Artigo em Inglês | MEDLINE | ID: mdl-15168335

RESUMO

Aortic explants were obtained from mouse fetuses and cultured in collagen gels. Immuno-fluorescence microscopy, antibodies (anti alpha1, alpha2 and alpha3 integrin subunits) were used. Fibroblastic cells migrated from the aortic explant after one day of cultivation. The migrating cells located in the peripheral part of the aortic explant were positive for alpha1 and alpha2 integrin subunit antibodies. Immuno-fluorescence-positive staining for the alpha3 integrin subunit antibody was clearly seen in the migrating cells located near the aortic explant and surrounding tube-like structures. In an immuno-electron microscope study performed by pre-embedding immuno labeling, gold particles associated with the alpha3 integrin subunit were found to reside on the membranes of the cells surrounding the capillary-like tubes. Two synthetic peptides, GRGDSP (Gly-Arg-Gly-Asp-Ser-Pro) and KDGEA (Lys-Asp-Gly-Glu-Ala), were added to the growth medium to study their effects on cell migration. KDGEA, a compound containing the recognition sequence for alpha2beta1 integrin, decreased cell migration, while GRGDSP exhibited no effect. The migration of fibroblastic cells is an important phenomenon for tube formation. The present study suggested that the alpha1 and alpha2 integrin subunits are both involved in the cell migration, and more specifically, that the alpha2 integrin subunit participates in cell migration through the KDGEA sequence. The alpha3 integrin subunit played a role in tube formation.


Assuntos
Integrina alfa1/metabolismo , Integrina alfa2/metabolismo , Integrina alfa3/metabolismo , Neovascularização Fisiológica , Subunidades Proteicas/metabolismo , Animais , Aorta/citologia , Movimento Celular/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Meios de Cultura , Fibroblastos/metabolismo , Fibroblastos/ultraestrutura , Técnica Indireta de Fluorescência para Anticorpo , Géis , Imuno-Histoquímica , Integrina alfa1/imunologia , Integrina alfa1/ultraestrutura , Integrina alfa2/imunologia , Integrina alfa2/ultraestrutura , Integrina alfa3/imunologia , Integrina alfa3/ultraestrutura , Magnésio/metabolismo , Camundongos , Microscopia Confocal , Microscopia Imunoeletrônica , Oligopeptídeos/farmacologia , Técnicas de Cultura de Órgãos , Fatores de Tempo
9.
Appl Microbiol Biotechnol ; 64(4): 505-14, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15088129

RESUMO

An agar-degrading bacterium, strain JAMB-A7, was isolated from the sediment in Sagami Bay, Japan, at a depth of 1,174 m and identified as a novel species of the genus Microbulbifer. The gene for a novel beta-agarase from the isolate was cloned and sequenced. It encodes a protein of 441 amino acids with a calculated molecular mass of 48,989 Da. The deduced amino acid sequence showed similarity to those of known beta-agarases in glycoside hydrolase family 16, with only 34-55% identity. A sequence similar to a carbohydrate-binding module was found in the C-terminal region of the enzyme. The recombinant agarase was hyper-produced extracellularly using Bacillus subtilis as the host, and the enzyme purified to homogeneity had a specific activity of 398 U (mg protein)(-1) at pH 7.0 and 50 degrees C. It was thermostable, with a half-life of 502 min at 50 degrees C. The optimal pH and temperature for activity were around 7 and 50 degrees C, respectively. The pattern of agarose hydrolysis showed that the enzyme was an endo-type beta-agarase, and the final main product was neoagarotetraose. The activity was not inhibited by NaCl, EDTA, and various surfactants at high concentrations. In particular, sodium dodecyl sulfate had no inhibitory effect up to 2%.


Assuntos
Alteromonadaceae/enzimologia , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Alteromonadaceae/classificação , Alteromonadaceae/isolamento & purificação , Sequência de Aminoácidos , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Sequência de Bases , Clonagem Molecular , Códon de Terminação/genética , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , Estabilidade Enzimática , Galactosídeos/análise , Galactosídeos/metabolismo , Genes Bacterianos , Genes de RNAr/genética , Sedimentos Geológicos/microbiologia , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Oligossacarídeos/análise , Oligossacarídeos/metabolismo , Fases de Leitura Aberta , Regiões Promotoras Genéticas , Sinais Direcionadores de Proteínas/genética , RNA Ribossômico 16S/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Sequências Repetitivas de Ácido Nucleico , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Temperatura , Microbiologia da Água
10.
Biochim Biophys Acta ; 1541(1-2): 102-13, 2001 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-11750666

RESUMO

Transport of cytoplasmically synthesized precursor proteins into chloroplasts, like the protein transport systems of mitochondria and the endoplasmic reticulum, appears to require the action of molecular chaperones. These molecules are likely to be the sites of the ATP hydrolysis required for precursor proteins to bind to and be translocated across the two membranes of the chloroplast envelope. Over the past decade, several different chaperones have been identified, based mainly on their association with precursor proteins and/or components of the chloroplast import complex, as putative factors mediating chloroplast protein import. These factors include cytoplasmic, chloroplast envelope-associated and stromal members of the Hsp70 family of chaperones, as well as stromal Hsp100 and Hsp60 chaperones and a cytoplasmic 14-3-3 protein. While many of the findings regarding the action of chaperones during chloroplast protein import parallel those seen for mitochondrial and endoplasmic reticulum protein transport, the chloroplast import system also has unique aspects, including its hypothesized use of an Hsp100 chaperone to drive translocation into the organelle interior. Many questions concerning the specific functions of chaperones during protein import into chloroplasts still remain that future studies, both biochemical and genetic, will need to address.


Assuntos
Cloroplastos/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas de Plantas/metabolismo , Precursores de Proteínas/metabolismo , Transporte Proteico , Proteínas de Cloroplastos , Citoplasma/metabolismo , Membranas Intracelulares/metabolismo , Pisum sativum , Sinais Direcionadores de Proteínas
11.
Int J Urol ; 8(10): 549-56, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11737483

RESUMO

BACKGROUND: Hypercalcemia is the most common of all paraneoplastic syndromes and has been reported to appear in up to 20% of patients with renal cell carcinoma (RCC). Humoral hypercalcemia of malignancy is believed to be induced when parathyroid hormone-related protein (PTHrP) is excessively produced in cancer cells and impairs the homeostasis of serum calcium concentrations. METHODS: Cancer cells were isolated from a surgical specimen and successfully cultured in a monolayer. The present study describes the establishment and characterization of new cell lines of RCC. RESULTS: Two different cell lines, designated SMRC-1 and SMRC-3, were established from human RCC, each of which had been continuously secreting PTHrP in vitro. The patient from whom the SMRC-3 cells were obtained was shown to have elevated levels of PTHrP and resultant hypercalcemia. Cultured SMRC-1 was spindle-shaped in morphology. SMRC-3 had pleomorphic polygonal shapes and formed typical epithelial monolayers. Both cell types secreted intact, C-terminal PTHrP and interleukin-6 in the culture medium. Cellular messenger RNA of PTHrP was analyzed by reverse transcriptase-polymerase chain reaction. The SMRC-1 cells showed chromosome numbers ranging from 42 to 47 with consistent structural abnormalities of add(4)(q23~25) and add(6)(q13). The chromosomal analysis of SMRC-3 revealed a modal number of 95 with consistent structural abnormalities of add(1)(p36) and der(1;3)(q10;p10). CONCLUSIONS: These cell lines could be good models for investigating the mechanism of PTHrP production and the relationship between this hormone and hypercalcemia.


Assuntos
Carcinoma de Células Renais/metabolismo , Neoplasias Renais/metabolismo , Biossíntese de Proteínas , Células Tumorais Cultivadas/metabolismo , Adulto , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Divisão Celular , Aberrações Cromossômicas , Cromossomos Humanos Par 1 , Humanos , Hipercalcemia/metabolismo , Interleucina-6/metabolismo , Cariotipagem , Neoplasias Renais/genética , Neoplasias Renais/patologia , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Proteína Relacionada ao Hormônio Paratireóideo , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas/citologia
12.
Acta Crystallogr D Biol Crystallogr ; 57(Pt 12): 1786-92, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11717490

RESUMO

The crystal structure of a highly alkaline low molecular weight pectate lyase (Pel-15) was determined at 1.5 A resolution by the multiple isomorphous replacement (MIR) method. This is the first pectate lyase structure from polysaccharide lyase family 3. The overall structure is a simple eight-turn right-handed parallel beta-helix domain with one long loop protruding from one side of the beta-helix. The low molecular weight of Pel-15 derives from the lack of N- and C-terminal extensions that are found in many beta-helix proteins. Although the structure has one calcium ion at pH 6.7, raising the pH to 9.5 results in the binding of an additional calcium ion. The common calcium ion found in both the pH 6.5 and 9.5 structures seems to stabilize both the beta-helix structure and the long protruding loop. The additional calcium ion found in the pH 9.5 structure alone may neutralize the acidic substrate. The region around the additional calcium ion is thought to bind to the substrate, as this region is rich in charged amino-acid residues which are required in catalysis.


Assuntos
Polissacarídeo-Liases/química , Sequência de Aminoácidos , Sítios de Ligação , Cálcio/metabolismo , Cristalização , Cristalografia por Raios X , Coleta de Dados , Concentração de Íons de Hidrogênio , Isoenzimas/química , Modelos Moleculares , Dados de Sequência Molecular , Peso Molecular , Polissacarídeo-Liases/isolamento & purificação , Conformação Proteica
13.
BJU Int ; 88(6): 611-21, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11678760

RESUMO

OBJECTIVE: To characterize a newly established human testicular carcinoma cell line that continuously produces alpha-fetoprotein (AFP), and to investigate the effects of retinoic acid on AFP production. MATERIALS AND METHODS: A 24-year-old man underwent a radical orchidectomy for a right testicular tumour and was found to have two separate metastatic lesions in the lungs, both of which were removed surgically. The cancer cells were isolated from one of the tumours, which was composed of undifferentiated germ cells and produced AFP; the cells were cultured in a monolayer. This cell line was designated as KU-MT. RESULTS: The cell line was successfully maintained both in athymic nude mice and in culture. Histological examination showed that the xenografted tumours were composed of cells in the reticular, solid and glandular patterns of a yolk sac tumour, and of embryonal carcinoma cells. These cells immunostained positively for AFP. On electron microscopy, the extracellular deposition of a basement lamina-like substance, a typical feature of yolk sac tumour, was detected. The AFP production in mice correlated well with the tumour weight of the xenograft. The cultured KU-MT cells were oval to polygonal in morphology and grew exponentially, with a population doubling time of approximately 2 days. Chromosomal analysis showed a modal number of 57 with consistent structural abnormalities of +add(1)(p13), del(1)(q32), del(2)(q31), add(6) (q21), +add(9)(p22), add(11)(p15), and add(14)(p11). Reverse-transcription polymerase chain reaction analysis showed that the retinoic acid receptors (RAR)-alpha, RAR-gamma, and retinoid X receptor-alpha were present in the cells. The expression of AFP mRNA was up-regulated in response to all-trans-retinoic acid; treatment with this agent caused morphological changes and induced apoptosis in the cells. CONCLUSIONS: This newly established cell line provides a reproducible model system that should offer a good insight into the differentiation of testicular carcinoma.


Assuntos
Neoplasias Testiculares/metabolismo , Células Tumorais Cultivadas/metabolismo , alfa-Fetoproteínas/metabolismo , Adulto , Animais , Antineoplásicos/uso terapêutico , Northern Blotting , Humanos , Cariotipagem , Neoplasias Pulmonares/secundário , Masculino , Camundongos , Camundongos Nus , Infecções por Mycoplasma/complicações , Transplante de Neoplasias , Neoplasias Testiculares/patologia , Tretinoína/uso terapêutico , Células Tumorais Cultivadas/efeitos dos fármacos , alfa-Fetoproteínas/efeitos dos fármacos
14.
Biosci Biotechnol Biochem ; 65(7): 1581-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11515542

RESUMO

The effects of solvent and reaction conditions on the catalytic activity of horseradish peroxidase (HRP) were investigated for oxidative polymerization of phenol in water/organic mixtures using hydrogen peroxide as an oxidant. Also, the structural changes of HRP were investigated by CD and absorption spectroscopy in these solvents. The results suggest that the yield of phenol polymer (the conversion of phenol to polymer) is strongly affected by the reaction conditions due to the structural changes of HRP, that is, the changes in higher structure of the apo-protein and dissociation or decomposition of the prosthetic heme. Optimum solvent compositions for phenol polymerization depend on the nature of the organic solvents owing to different effects of the solvents on HRP structure. In addition to initial rapid changes, slower changes of HRP structure occur in water/organic solvents especially at high concentrations of organic solvents. In parallel with these structural changes, catalytic activity of HRP decreases with time in these solvents. At higher reaction temperatures, the yield of the polymer decreases, which is also ascribed to modification of HRP structure. It is known that hydrogen peroxide is an inhibitor of HRP, and the yield of phenol polymer is strongly dependent on the manner of addition of hydrogen peroxide to the reaction solutions. The polymer yield decreases significantly when hydrogen peroxide was added to the reaction solution in a large amount at once. This is probably due to inactivation of HRP by excess hydrogen peroxide. From the CD and absorption spectra, it is suggested that excess hydrogen peroxide causes not only decomposition of the prosthetic heme but also modification of the higher structure of HRP.


Assuntos
Flavonoides , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Dicroísmo Circular , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática , Peroxidase do Rábano Silvestre/antagonistas & inibidores , Peróxido de Hidrogênio/farmacologia , Estrutura Molecular , Oxirredução , Fenol/metabolismo , Fenóis/metabolismo , Polímeros/metabolismo , Polifenóis , Solventes , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Água
15.
Brain Res Bull ; 54(2): 159-65, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11275405

RESUMO

In the cervical and lumbosacral enlargements of the chicken, there are seven spinocerebellar nuclei, the Clarke's column, the spinal border cells, the ventral margin of the ventral horn of both enlargements, and the ventral marginal nucleus in the lumbosacral enlargement. In the present study, we investigated the laterality of spinocerebellar tract axons and the distribution of the spinocerebellar tract neurons projecting into the anterior or posterior part of the cerebellum in these seven nuclei by retrograde transport of wheat germ agglutinin-horseradish peroxidase. The spinocerebellar tract neurons with uncrossed axons were found in the cervical Clarke's column and the cervical spinal border cells, and with crossed ones in the lumbar Clarke's column, lumbar spinal border cells, lumbar lamina IX included in the ventral margin of the ventral horn of the lumbosacral enlargement, and the ventral marginal nucleus. The ventral margin of the ventral horn of the cervical enlargement and lumbar lamina VIII included in the ventral margin of the ventral horn of the lumbosacral enlargement issued spinocerebellar tract axons bilaterally. The spinocerebellar tract neurons of the lumbar spinal border cells and lumbar lamina IX projected to the anterior part of the cerebellum only. And those of the other nuclei projected to both the anterior and posterior parts.


Assuntos
Células do Corno Anterior/anatomia & histologia , Axônios , Cerebelo/anatomia & histologia , Células do Corno Posterior/anatomia & histologia , Tratos Espinocerebelares/anatomia & histologia , Animais , Células do Corno Anterior/fisiologia , Axônios/fisiologia , Cerebelo/fisiologia , Vértebras Cervicais , Galinhas , Feminino , Região Lombossacral , Sondas Moleculares , Células do Corno Posterior/fisiologia , Medula Espinal/anatomia & histologia , Medula Espinal/fisiologia , Tratos Espinocerebelares/fisiologia , Conjugado Aglutinina do Germe de Trigo-Peroxidase do Rábano Silvestre
16.
Int J Urol ; 8(1): 17-22, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11168692

RESUMO

BACKGROUND: ACT-1, a new cell line of human adrenocortical carcinoma, has been established and successfully maintained in culture. This study examined the biological characteristics of the cells. METHODS: The tumor cells were isolated from a surgical specimen of the tumor thrombus and cultured in monolayer. RESULTS: Histologically, the primary tumor was composed of a solid proliferation of large polygonal cells. A part of the atrophic adrenal cortex remained at the periphery of the tumor. The cultured ACT-1 cells were spindle-shaped in morphology and grew exponentially with an approximate population doubling time of 24 h. A chromosomal analysis revealed a modal number of 61 with consistent structural abnormalities of add(3)(q11), add(9)(p11), and add(16)(ql1). The expression of 3beta-hydroxysteroid dehydrogenase was observed in the ACT-1 cells as well as in normal human adrenal glands. CONCLUSIONS: The ACT-1 cell line provides a reproducible model system which gives good insight into the oncogenesis of adrenocortical carcinoma.


Assuntos
Neoplasias do Córtex Suprarrenal/patologia , Carcinoma Adrenocortical/patologia , Células Tumorais Cultivadas , Neoplasias do Córtex Suprarrenal/genética , Carcinoma Adrenocortical/genética , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade
18.
Exp Anim ; 50(5): 409-15, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11769543

RESUMO

We studied the characteristics of the rhythmicity of heart rate (HR), body temperature (BT), and locomotor activity (LA) in conscious and unrestrained guinea pigs using a telemetry system. HR and/or LA in some guinea pigs clearly showed circadian rhythms, but in others there were no significant daily patterns; BT did not show significant daily rhythms. These results suggest that guinea pigs might have different individual characteristics of rhythmicity, and we should, therefore, be careful when using guinea pigs in chrono-biomedical research. We believe that the results of this study may be useful for future biomedical studies using guinea pigs.


Assuntos
Temperatura Corporal/fisiologia , Cobaias/fisiologia , Frequência Cardíaca/fisiologia , Locomoção/fisiologia , Animais , Ritmo Circadiano , Masculino , Telemetria/veterinária
19.
Chemistry ; 7(23): 5011-28, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11775675

RESUMO

Reaction of the dinuclear M(II)-bis(mu-hydroxo) complexes of nickel and cobalt, [(M(II)(TpR)]2(mu-OH)2] (M = Ni; 3Ni M = Co: 3Co), with one equivalent of H2O2 yields the corresponding M(III)-bis(mu-oxo) complexes, [[M(III)(TpR)]2-(mu-O)2] (M=Ni; 2Ni, M=Co: 2Co). The employment of a series of TpMe2,X (TpMe2,X = hydrotris(3,5-dimethyl-4-X-1-pyrazolyl)borate; X = Me, H, Br) as a metal supporting ligand makes it possible to isolate and structurally characterize the thermally unstable M(III)-bis-(mu-oxo) complexes 2Ni and 2Co. Both the starting (3Ni and 3Co) and resulting complexes (2Ni and 2Co) contain five-coordinate metal centers with a slightly distorted square-pyramidal geometry. Characteristic features of the nickel complexes 2Ni, such as the two intense absorptions around 400 and 300 nm in the UV-visible spectra and the apparent diamagnetism, are very similar to those of the previously reported bis(mu-oxo) species of Cu(III) and Ni(III) with ligands other than TpR, whereas the spectroscopic properties of the cobalt complexes 2Co (i.e., paramagnetically shifted NMR signals and a single intense absorption appearing at 350 nm) are clearly distinct from those of the isostructural nickel compounds 2Ni. Thermal decomposition of 2Ni and 2Co results in oxidation of the inner saturated hydrocarbyl substituents of the TpR ligand. Large kH/kD values obtained from the first-order decomposition rates of the TpMe3 and Tp(CD3)2,Me derivatives of 2 evidently indicate that the rate-determining step is an hydrogen abstraction from the primary C-H bond of the methyl substituents. mediated by the M(III)2-(mu-O)2 species. The nickel complex 2Ni shows reactivity about 10(3) times greater than that of the cobalt analogue 2Co. The oxidation ability of the M(III)(mu-O)2M(III) core should be affected by the hindered TpR ligand system, which can stabilize the +2 oxidation state of the metal centers.


Assuntos
Cobalto/química , Níquel/química , Compostos Organometálicos/química , Oxigênio/metabolismo , Cristalografia por Raios X , Ligantes , Metaloproteínas/química , Estrutura Molecular , Oxirredução , Análise Espectral
20.
Ann Otol Rhinol Laryngol ; 109(11): 1055-64, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11089998

RESUMO

A scanning electron microscopic study was made on the morphological changes occurring with age in collagen and elastic fibers in the lamina propria of the human vocal fold. We obtained the specimens from 32 autopsy cases ranging from 20 gestational weeks to 22 postnatal years and submitted them to digestion treatments with 10% sodium hydroxide and 90% formic acid. The vocal folds in fetuses and neonates consisted of sparse and dense areas of collagen and elastic fibers, and the vocal ligament was not found. In subjects 5 years of age, a deep dense area was found in the anterior and posterior maculae flavae, and longitudinal fibers were noted between the maculae. A structure of superficial versus deep layers appeared in children older than 10 years of age. The layered structure of the lamina propria was complete around 17 years of age. The development of the layered structure and the maturity of the fibers appeared to reflect the complexity of phonatory function during adolescence.


Assuntos
Células do Tecido Conjuntivo/citologia , Células do Tecido Conjuntivo/fisiologia , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/fisiologia , Prega Vocal/citologia , Prega Vocal/fisiologia , Adolescente , Adulto , Fatores Etários , Envelhecimento/fisiologia , Criança , Pré-Escolar , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Feminino , Humanos , Lactente , Recém-Nascido , Músculos Laríngeos/citologia , Músculos Laríngeos/fisiologia , Masculino
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