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1.
J Oral Rehabil ; 44(12): 948-956, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28853166

RESUMO

A knowledge gap regarding masticatory performance in preschool children exists, which in turn delays intervention for preventive care; therefore, a method to easily assess performance is needed. The purpose of this study is to investigate the feasibility of assessing masticatory performance using colour-changeable chewing gum and to investigate masticatory performance-related factors in preschool children. This cross-sectional survey was conducted in two childcare facilities and our laboratory. First, a one-third quantity of colour-changeable chewing gum was masticated by six adults to assess the nature and progression of colour changes in this quantity. Then, masticatory performance in 370 children 4-6 years of age was assessed using the same quantity of colour-changeable chewing gum (60 chew strokes). The maximum bite force, body height, weight, age and number of healthy teeth were recorded. A t-test was performed to determine whether gum-chewing experience or lack thereof produced a significant difference in masticatory performance. The Spearman's rank correlation coefficient was then determined for masticatory performance assessment values and other factors solely for children with gum-chewing experience. Measurements from 259 children were obtained. Children with gum-chewing experience demons trated significantly higher assessment values and were deemed to have been correctly assessed. A very weak but significant positive correlation was observed only between masticatory performance and the number of healthy teeth. The masticatory performance of preschool children was easily assessed using colour-changeable chewing gum. The assessment values demonstrated significant correlation with the number of healthy teeth, but not with maximum bite force, body height, weight or age.


Assuntos
Goma de Mascar , Cor , Mastigação/fisiologia , Destreza Motora/fisiologia , Força de Mordida , Pré-Escolar , Estudos Transversais , Dentição , Comportamento Alimentar , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
2.
Nat Cell Biol ; 3(2): 158-64, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11175748

RESUMO

Under conditions of endoplasmic reticulum (ER) stress, mammalian cells induce both translational repression and the unfolded protein response that transcriptionally activates genes encoding ER-resident molecular chaperones. To date, the only known pathway for translational repression in response to ER stress has been the phosphorylation of eIF-2alpha by the double-stranded RNA-activated protein kinase (PKR) or the transmembrane PKR-like ER kinase (PERK). Here we report another pathway in which the ER transmembrane kinase/ribonuclease IRE1beta induces translational repression through 28S ribosomal RNA cleavage in response to ER stress. The evidence suggests that both pathways are important for efficient translational repression during the ER stress response.


Assuntos
Retículo Endoplasmático/metabolismo , Proteínas de Membrana , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Sequência de Aminoácidos , Animais , Antibacterianos/farmacologia , Apoptose/fisiologia , Northern Blotting , Western Blotting , Células Cultivadas , Doxiciclina/farmacologia , Endorribonucleases , Humanos , Imuno-Histoquímica , Dados de Sequência Molecular , Fosforilação , Biossíntese de Proteínas , Proteínas Serina-Treonina Quinases/química , Estrutura Terciária de Proteína , RNA Ribossômico 28S/metabolismo , Alinhamento de Sequência , Transfecção , Tunicamicina/farmacologia , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
3.
Gene ; 261(2): 321-7, 2000 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-11167020

RESUMO

Several endoplasmic reticulum (ER)-resident proteins contain a unique C-terminal sequence (KDEL) which is required for the retention of these proteins in the ER. By searching a mouse EST database for records containing the nucleotide sequence encoding the KDEL motif, we extracted cDNAs encoding putative novel ER-resident proteins in addition to all of the known ER proteins bearing the KDEL motif. Using the sequence information obtained by this database search, we cloned the cDNA encoding a novel KDEL motif-bearing protein, ER protein 58 (EP58), sharing no significant homology to any of the known ER-resident proteins. Subcellular localization of EP58 in the ER was confirmed by cytoimmunofluorescence studies using epitope-tagged EP58. The EP58 gene was primarily expressed in embryo, placenta, and adult heart. Neither heat shock nor ER stress as tested here was sufficient to induce expression of the EP58 gene. A putative role of the N-terminal half of EP58 in protein-protein interaction is suggested by its similarity to the filamin rod domain. Similarity of the EP58 sequence with bacterial and fungus proteins suggests a possible role for EP58 in polysaccharide biosynthesis.


Assuntos
Retículo Endoplasmático/metabolismo , Etiquetas de Sequências Expressas , Receptores de Peptídeos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Células COS , Linhagem Celular , DNA Complementar/química , DNA Complementar/genética , DNA Recombinante , Bases de Dados Factuais , Embrião de Mamíferos/metabolismo , Feminino , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Proteínas de Membrana/genética , Camundongos , Microscopia Confocal , Dados de Sequência Molecular , Oligopeptídeos , Peptídeos/genética , Peptídeos/metabolismo , Plasmídeos/genética , RNA/genética , RNA/metabolismo , Receptores de Peptídeos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Software , Distribuição Tecidual
4.
Cancer Lett ; 157(1): 77-85, 2000 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-10893445

RESUMO

A total of 23 ferulic acid (FA) derivatives were synthesized, and investigated for their inhibitory effects on 12-O-tetradecanoylphorbol-13-acetate-induced Epstein-Barr virus (EBV) activation and superoxide (O(2)(-)) generation. Most of the derivatives showed significant EBV activation suppression or cytotoxicity at a concentration of 100 microM, with FA15 as the most potent suppressor. In both assays, FA6-FA17, bearing straight- or branched-alkyl side chains, exhibited marked suppression of O(2)(-) generation, with both FA16 and FA17 being highly active, while FA itself was virtually inactive. The activity differences seen between FA16/FA17 and FA are attributable, at least in part, to their cellular incorporating efficiencies. Further, both FA15 and FA21 attenuated the expression of inducible nitric oxide synthase and cyclooxygenase-2 proteins, while FA did not. Our results suggest that these novel FA derivatives are effective chemopreventive agents.


Assuntos
Anticarcinógenos/farmacologia , Ácidos Cumáricos/farmacologia , Interferon gama/antagonistas & inibidores , Lipopolissacarídeos/antagonistas & inibidores , Acetato de Tetradecanoilforbol/antagonistas & inibidores , Animais , Anticarcinógenos/farmacocinética , Linhagem Celular , Ácidos Cumáricos/farmacocinética , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase/farmacologia , Interações Medicamentosas , Indução Enzimática/efeitos dos fármacos , Células HL-60/efeitos dos fármacos , Células HL-60/metabolismo , Herpesvirus Humano 4/efeitos dos fármacos , Herpesvirus Humano 4/genética , Humanos , Interferon gama/farmacologia , Isoenzimas/antagonistas & inibidores , Isoenzimas/biossíntese , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Proteínas de Membrana , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase Tipo II , Prostaglandina-Endoperóxido Sintases/biossíntese , Relação Estrutura-Atividade , Superóxidos/antagonistas & inibidores , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Ativação Viral/efeitos dos fármacos
5.
Am J Ophthalmol ; 115(1): 21-5, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8420373

RESUMO

We examined the aqueous humor by electron microscopy of four patients with atopic dermatitis and retinal detachment. All the patients had a moderate number of cells in the aqueous humor. Cataract impaired fundus visualization except for one patient with aphakia. A flat retinal detachment involved a wide area detected by echography. The intraocular pressure in the eyes with retinal detachment demonstrated a marked diurnal fluctuation compared with that of the fellow eye. The aqueous cells consisted predominantly of photoreceptor outer segments. This finding does not support the theory that aqueous cells in atopic dermatitis are of inflammatory origin. Photoreceptor outer segments in aqueous humor are indicative of rhegmatogenous retinal detachment in patients with atopic dermatitis.


Assuntos
Humor Aquoso/citologia , Dermatite Atópica/patologia , Descolamento Retiniano/patologia , Segmento Externo da Célula Bastonete/patologia , Adolescente , Adulto , Dermatite Atópica/complicações , Feminino , Humanos , Masculino , Microscopia Eletrônica , Descolamento Retiniano/complicações
6.
Anticancer Res ; 19(5A): 3757-61, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10625954

RESUMO

We suggest that chemical raw materials can best be obtained from natural resources. Ferulic acid is easily prepared in large quantities from rice bran pitch, a blackish brown waste oil with high viscosity, discharged in the process of the rice bran oil production. As an application of ferulic acid, potential cancer chemopreventive agents could be synthesized using organic synthetic methods.


Assuntos
Anticarcinógenos/síntese química , Ácidos Cumáricos/isolamento & purificação , Oryza/química , Ácidos Cumáricos/síntese química
7.
Pathol Res Pract ; 196(3): 205-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10729926

RESUMO

A case of elastofibroma occurring in the sigmoid colon of a 69 year-old woman is reported. The woman presented for survey of her gastrointestinal tract. Colonoscopy disclosed two polyps in the sigmoid colon, one of which was clinically considered to be recurrent adenoma. Histologically, the lesion had characteristic eosinophilic fibers and globules, termed elastofibroma fibers with hematoxylin and eosin stain. In addition, these elastinophilic materials were digested by elastase. Histological evaluation confirmed the diagnosis of elastofibroma. Our case might suggest that it is the result of long-term fibrosis after previous endoscopic resection of a sigmoid colonic adenoma.


Assuntos
Adenoma/patologia , Colo Sigmoide/patologia , Pólipos do Colo/patologia , Fibroma/patologia , Segunda Neoplasia Primária/patologia , Adenoma/cirurgia , Idoso , Pólipos do Colo/cirurgia , Diagnóstico Diferencial , Endoscopia Gastrointestinal , Feminino , Fibroma/cirurgia , Humanos , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/cirurgia , Segunda Neoplasia Primária/cirurgia
8.
J Exp Clin Cancer Res ; 21(2): 203-11, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12148579

RESUMO

To elucidate early molecular events related to colon carcinogenesis, we examined alterations in the expression of colon cancer-related genes such as cyclooxygenase (COX)-2, APC and c-Myc, cell proliferation and apoptosis in the background colon mucosa, and K-ras mutation at aberrant crypt foci (ACF) in the colons of azoxymethane (AOM)-treated rats 4 weeks after the first exposure to AOM. About 40 ACF/colon were induced in the colons of rats treated with AOM (Group 1); however, rats not treated with AOM (Group 2) showed no ACF formation in the colon. The level of AgNORs in the colonic mucosa was significantly higher in Group 1 than in Group 2 (P<0.01). The colonic mucosa in Group 1 looked macroscopically and histologically normal, but the proliferative activity of the mucosa of rats treated with AOM was clearly elevated. COX-2 mRNA expression was not detected in normal colonic mucosa in Group 2, but 3 out of 10 rats in Group 1 showed COX-2 mRNA expression in their colons by reverse transcription (RT)-polymerase chain reaction (PCR). There was a tendency toward an increased expression level of COX-2 in the AOM-treated group. The level of APC mRNA expression in Group 1 was significantly lower than that in Group 2 (P<0.01). Moreover, the level of c-Myc mRNA expression in Group 1 was significantly higher than that in Group 2 (P<0.01). An average of 0.034+/-0.006% apoptosis in colonic mucosa was detected in Group 1; the incidence of apoptosis in Group 2 was 0.021+/-0.005%. The difference between Groups 1 and 2 was significant (P<0.01). These results indicate that apoptosis was possibly induced to eliminate cells damaged by AOM administration. Six out of 22 (27%) ACF with 4 or more crypts showed K-ras mutations at codon 12; all mutations were G to A transitions (GGT to GAT). ACF with 1-3 crypts showed no mutations in the K-ras gene. In conclusion, AOM caused an increase in COX-2 and c-Myc mRNA expression, a decrease in APC mRNA expression, induction of apoptosis in normal-appearing colonic mucosa, and a K-ras mutation in ACF with 4 or more crypts. These findings may help to identify key targets in the early steps of colon carcinogenesis, against which drugs that would be broadly effective for chemoprevention of colon cancer could be developed.


Assuntos
Azoximetano/toxicidade , Carcinógenos/toxicidade , Colo/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Lesões Pré-Cancerosas/metabolismo , Proteína da Polipose Adenomatosa do Colo/genética , Proteína da Polipose Adenomatosa do Colo/metabolismo , Animais , Apoptose/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/patologia , Ciclo-Oxigenase 2 , Genes ras/genética , Marcação In Situ das Extremidades Cortadas , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Região Organizadora do Nucléolo/metabolismo , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/patologia , Prostaglandina-Endoperóxido Sintases/genética , Prostaglandina-Endoperóxido Sintases/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos F344
9.
Biofactors ; 21(1-4): 315-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15630218

RESUMO

Antioxidant activity and biological properties of ferulic acid (FA) are well recognized. This study was designed to estimate the potential utility of FA administered orally at low dosage for improvement of hyperglycemia in diabetes. With this aim we have evaluated the hypoglycemic effect of FA in two type diabetic animal models: (1) streptozotocin (STZ)-induced diabetic mice, a model of insulin-dependent diabetes mellitus (IDDM); (2) KK-Ay mice, a model of non-insulin dependent diabetes mellitus (NIDDM). In addition, we measured the production of thiobarbituric acid-reactive substances (TBARS) in brown adipose tissues of diabetic mice at the end of FA feeding experiment. FA at 0.01% and 0.1% of basal diet showed to suppress significantly blood glucose levels in STZ-induced diabetic mice. In KK-Ay mice 0.05% FA suppressed effectively blood glucose levels. In addition, FA inhibited the lipid peroxidation in brown adipose tissue of diabetic mice. Taken together, these findings suggest that dietary FA may be useful in alleviating oxidative stress and attenuating the hyperglycemic response associated with diabetes.


Assuntos
Antioxidantes/uso terapêutico , Ácidos Cumáricos/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Modelos Animais de Doenças , Técnicas In Vitro , Masculino , Camundongos , Camundongos Mutantes , Oryza , Fitoterapia , Preparações de Plantas/uso terapêutico , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
10.
Rinsho Ketsueki ; 31(6): 842-6, 1990 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-2214175

RESUMO

A 76-year-old female was admitted to our hospital because of anemia. Complete blood count was as follows: RBC 2.37 X 10(6)/microliters, Hb 7.7 g/dl, WBC 2,600/microliters, Plt 105 X 10(3)/microliters. A bone marrow aspirate revealed 40.8% plasmacytoid cells showing the characteristics of plasma cells by electron microscopy. Total serum protein was 5.4 g/dl. Monoclonal protein was not observed by electrophoresis. On immunoelectrophoresis, M-bow was not observed in the serum or in 50-fold concentrated urine. The plasma cells were negative for cytoplasmic IgG, M, A, E, D, kappa or lambda by immunoperoxidase studies. Although radiologic studies of the bones did not reveal destructive or punched out lesions, we diagnosed this case as a nonproducing myeloma and the patient responded to MP therapy. This case was considered interesting as regards the pathological entity of myeloma.


Assuntos
Medula Óssea/patologia , Osso e Ossos/patologia , Mieloma Múltiplo/diagnóstico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Humanos , Melfalan/administração & dosagem , Microscopia Eletrônica , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Plasmócitos/ultraestrutura , Prednisolona/administração & dosagem
11.
Biotechnology (N Y) ; 8(11): 1036-40, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1366931

RESUMO

We have developed a direct expression system for high-level production of recombinant human interleukin-6 (rhIL-6) in Escherichia coli. In this system, (i) the natural N-terminal coding region of the hIL-6 gene was replaced by a synthetic sequence containing A-T rich codons, (ii) dual Shine-Dalgarno (SD) sequences were employed, (iii) an A-T rich segment was inserted in front of the initiation codon to avoid putative mRNA secondary structure in the region and (iv) the natural amber termination codon of the hIL-6 gene was changed to an ocher stop codon. The hIL-6 polypeptide, synthesized at a high level, formed cytoplasmic inclusion bodies. After refolding, the N-terminal methionine was removed by aminopeptidase-P in vitro. The purified recombinant hIL-6 had B-cell differentiation activity equivalent to natural IL-6 from a human T-cell culture.


Assuntos
Escherichia coli/genética , Interleucina-6/genética , Linfócitos B/efeitos dos fármacos , Sequência de Bases , Cromatografia Líquida de Alta Pressão , Deleção Cromossômica , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Expressão Gênica , Genes Sintéticos , Humanos , Interleucina-6/biossíntese , Interleucina-6/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Metionina/genética , Dados de Sequência Molecular , Plasmídeos , Conformação Proteica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Transfecção
14.
Res Commun Chem Pathol Pharmacol ; 81(2): 209-20, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8210699

RESUMO

The present study investigated the relationship between the concentration of the reduced form of glutathione (GSH) and GSH-dependent enzyme activities in the gastric mucosa during chronic liver injury caused by carbon tetrachloride (CCl4) in rats. There were significant decreases in the mucosal GSH concentration and glutathione S-transferase (GST) activity as well as a significant increase in gamma glutamyltransferase (GGT) activity in rats exposed to CCl4 (all p < 0.001). However, no significant change was observed in glutathione peroxidase (GSH-Px) activity. A negative correlation was seen between the mucosal GSH concentration and GGT activity (p < 0.05) and a positive correlation between the GSH concentration and GST activity (p < 0.01). No correlation was noted between the GSH concentration and GSH-Px activity. Gastric mucosal damage, as evaluated by macroscopic observation and light microscopy, was more damaged in the rats exposed to CCl4 than in the control group. There was a significant correlation between histologic mucosal damage and GGT activity (p < 0.05) as well as a negative correlation between the number of macroscopic lesions and GSH and between the number of macroscopic lesions and GST (p < 0.01). From the observed abnormalities of GSH and GSH-dependent enzymes in the gastric mucosa of the rats exposed to CCl4, GSH content and the activities of GSH-dependent enzymes might play a role in the gastric mucosal defense mechanism during chronic liver injury.


Assuntos
Tetracloreto de Carbono/toxicidade , Mucosa Gástrica/efeitos dos fármacos , Glutationa/metabolismo , Fígado/efeitos dos fármacos , Animais , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Glutationa Peroxidase/análise , Glutationa Transferase/análise , Masculino , Ratos , Ratos Wistar
15.
Res Commun Chem Pathol Pharmacol ; 79(2): 141-50, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8095731

RESUMO

The present study investigated the relationship between the concentration of the reduced form of glutathione (GSH) and GSH-dependent enzyme activities in the gastric mucosa during acute liver injury caused by carbon tetrachloride (CCl4) in rats. Transient decreases in glutathione S-transferase (GST) activity and in glutathione peroxidase (GSH-Px) activity was observed (p < 0.01). GSH concentration also decreased (p < 0.01) but then transiently increased (p < 0.05). Gamma-glutamyltransferase (GGT) activities in rats killed 6, 12, and 24 hr after exposure to CCl4 were all higher than in the control group (p < 0.01). There was a significant correlation between GSH concentration and GST activity (p < 0.05) and between GSH concentration and GSH-Px activity (p < 0.01). However, there was no correlation between GSH concentration and GGT activity. The gastric mucosa, as judged by light microscopy, was slightly more damaged in the rats exposed to CCl4 than in the control group. From the observed abnormalities of GSH and GSH-dependent enzymes in the gastric mucosa of the rats exposed to CCl4, changes in GSH content and GSH-related enzymes in gastric mucosa may be important in gastric protection during acute liver injury.


Assuntos
Mucosa Gástrica/enzimologia , Glutationa/metabolismo , Hepatopatias/fisiopatologia , Fígado/fisiopatologia , Animais , Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas , Mucosa Gástrica/patologia , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Masculino , Ratos , Ratos Wistar , gama-Glutamiltransferase/metabolismo
16.
Appl Environ Microbiol ; 54(6): 1523-9, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16347663

RESUMO

Two immunologically related cellobiohydrolases, cellobiohydrolase I (CBH I) and cellobiohydrolase II (CBH II), were purified from Aspergillus ficum. The Avicel-adsorbable CBH I (molecular weight, 128,000) digested Avicel, cotton, and cellulose powder to cellobiose, but the Avicel-unadsorbable CBH II (molecular weight, 50,000) could not digest those substrates. Both enzymes hydrolyzed insoluble cellooligosaccharides (DP 25) to cellobiose. High-pressure liquid chromatographic analysis of soluble cellooligosaccharide hydrolysates revealed that both enzymes split off strictly cellobiose units from the nonreducing end of the cellulose chain with an exowise mechanism. CBH I showed glucosyltransferase activity, but CBH II did not. The N-bromosuccinimideoxidized CBH I was completely inactive but retained the ability to adsorb to Avicel. This suggested that CBH I has separate sites for binding to cellulose and for catalyzing cleavage of glycosidic linkages. Cellobiohydrolases were of two types, CBH I and CBH II. The former can adsorb to and digest Avicel, while the latter can do neither.

17.
J Org Chem ; 66(24): 8030-6, 2001 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-11722201

RESUMO

Tannin-like p-tert-butylcalix[4]arene 1,3-digallate was synthesized, and its conformational property was investigated by dynamic (1)H NMR and X-ray crystallography. It was found that the 3-OH (or 5-OH) group of the galloyl group in p-tert-butylcalix[4]arene 1,3-digallate is placed at the position where an unusual nonbonded close contact is observed between the OH group and the aromatic ring of the galloyl group facing each other. The calixarene 1,3-diesters of various hydroxybenzoic acids were also prepared, and the conformational properties of those calixarenes were compared with that of p-tert-butylcalix[4]arene 1,3-digallate. A significant contribution of the 3- and 5-OH groups in pendant groups toward the close contact was found. It was suggested that the conformation of p-tert-butylcalix[4]arene 1,3-digallate was stabilized by intramolecular hydrogen bonds including OH.O and OH-pi interactions.


Assuntos
Ésteres/química , Hidroxibenzoatos/síntese química , Substâncias Macromoleculares , Calixarenos , Cristalografia por Raios X , Ácido Gálico/química , Ligação de Hidrogênio , Taninos Hidrolisáveis , Hidroxibenzoatos/química , Espectroscopia de Ressonância Magnética , Conformação Molecular
18.
Org Lett ; 2(6): 779-781, 2000 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-10814427

RESUMO

p-tert-Butylcalix[4]arene 1,3-digallate, which contains a nonbonded close contact between galloyl groups, was synthesized and its structure was determined by dynamic (1)H NMR and X-ray crystallography. The electronic spectra showed that a new absorption band of the complexes appeared at a longer wavelength region upon adding Ag(+) ion. This spectral shift was explained in terms of the interaction between the facing galloyl groups of the lower rim of the calixarene framework.

19.
Bioorg Med Chem Lett ; 10(13): 1439-42, 2000 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-10888327

RESUMO

Ester compounds consisting of ferulic acid and myo-inositol, obtained from rice bran, were synthesized. The inhibitory effects of these feruloyl-myo-inositols on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced superoxide (O2-) generation were examined using differentiated HL-60 cells. Among the derivatives tested, only 3,4,5,6-tetra-O-acetyl-1,2-di-O-[3-(4'-acetoxy-3'-methoxyphenyl)-2-pr openoyl]-myo-inositol (3) showed a distinct inhibitory activity.


Assuntos
Anticarcinógenos/síntese química , Antioxidantes/síntese química , Inositol/análogos & derivados , Inositol/síntese química , Superóxidos/metabolismo , Anticarcinógenos/farmacologia , Antioxidantes/farmacologia , Desenho de Fármacos , Ésteres/química , Granulócitos/efeitos dos fármacos , Células HL-60 , Humanos , Estrutura Molecular , Acetato de Tetradecanoilforbol/farmacologia
20.
Pediatr Res ; 29(2): 196-200, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1901642

RESUMO

In an attempt to understand the dynamic change of the gonadotropin-releasing hormone-pituitary axis during the transitional stage from prepuberty to puberty, we investigated gonadotropin secretory patterns using a highly sensitive assay system and frequent blood sampling technique in children with Turner syndrome aged 5-17 y. Blood samples were collected every 20 min for 24 h in 16 cases, or every 30 min for 9 h (daytime 5 h, nighttime 4 h) in nine cases. Serum LH and FSH were measured by time-resolved fluoroimmunoassay. A 24-h profile of LH and FSH was analyzed by a computerized pulse detection program (PC-PULSAR). As early as 5 to 6 y of age, mean daytime LH concentration was significantly higher than nighttime concentration and pulsatile LH secretion existed throughout the day and night. At about 9 to 11 y of age, corresponding to the early stage of puberty, a dramatic increase in LH concentration and amplitude was observed, and both concentration and pulse amplitude were much higher during the night than during the day. However, these day-night differences became less clear at ages corresponding to late pubertal stages. Pulse frequency of LH secretion remained almost constant throughout the day and night at all ages investigated. As for FSH concentration, a trend similar to that of LH was observed, although day-night differences and age-related changes were less remarkable. Furthermore, pulsatile FSH secretion was detected in only a small number of the cases. These findings suggest that in Turner syndrome the hypothalamic gonadotropin-releasing hormone oscillator is functioning actively with constant frequency before the onset of puberty.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Hormônio Foliculoestimulante/metabolismo , Hormônio Luteinizante/metabolismo , Síndrome de Turner/fisiopatologia , Adolescente , Fatores Etários , Criança , Pré-Escolar , Ritmo Circadiano , Feminino , Humanos , Hipófise/metabolismo , Puberdade/fisiologia
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