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1.
Cytopathology ; 29(3): 262-266, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29578263

RESUMO

BACKGROUND: Telomeres are tandem repeats of TTAGGG at the end of eukaryotic chromosomes that play a key role in preventing chromosomal instability. The aim of the present study is to determine telomere length using fluorescence in situ hybridisation (FISH) on cytological specimens. METHODS: Aspiration samples (n = 41) were smeared on glass slides and used for FISH. RESULTS: Telomere signal intensity was significantly lower in positive cases (cases with malignancy, n = 25) as compared to negative cases (cases without malignancy, n = 16), and the same was observed for centromere intensity. The difference in DAPI intensity was not statistically significant. The ratio of telomere to centromere intensity did not show a significant difference between positive and negative cases. There was no statistical difference in the signal intensities of aspiration samples from ascites or pleural effusion (n = 23) and endoscopic ultrasound-guided FNA samples from the pancreas (n = 18). CONCLUSIONS: The present study revealed that telomere length can be used as an indicator to distinguish malignant and benign cells in cytological specimens. This novel approach may help improve diagnosis for cancer patients.


Assuntos
Telômero/genética , Ascite/genética , Ascite/patologia , Instabilidade Cromossômica/genética , Fluorescência , Humanos , Hibridização in Situ Fluorescente/métodos , Pâncreas/patologia , Derrame Pleural/genética , Derrame Pleural/patologia
2.
Water Sci Technol ; 61(5): 1183-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20220240

RESUMO

Hydrotalcite (HTAL-Cl), an inorganic anion exchanger, is of use as an adsorbent for the removal of arsenate (As(V)) in water systems. The adsorption properties of HTAL-Cl for As(V) and the effects of co-existing anions on the As(V) removal performance were investigated in this work. Under the conditions of pH>or=4, the adsorption capacity for As(V) gradually decreased with an increase of pH, but As(V) was removed effectively within the range of pH = 5-8. Co-existing anions interfered As(V) removal, and the effect decreased in the order of HPO(4)(2-) > HCO(3)(-) > SO(4)(2-) > Cl(-). In binary solute systems containing phosphate and As(V), the maximum adsorption capacity of HTAL-Cl was 0.95 mmol g(-1) for phosphate and 0.65 mmol g(-1) for As(V): the total of these values corresponded to the maximum adsorption capacity for As(V) in single solute systems. The adsorption isotherms in these binary solute systems were approximated by the following modified Langmuir equations:As(V): q(As) = 18.7 radicalC(As)/(1 + 21.5 radicalC(P) + 12.8 radicalC(As)), phosphate : q(P) = 33.1 radicalC(P)/(1 + 21.5 radicalC(P) + 12.8 radicalC(As)). The column adsorption experiments showed that the adsorbed As(V) was released by the phosphate adsorption, because phosphate was adsorbed more strongly on HTAL-CL than As(V).


Assuntos
Hidróxido de Alumínio/química , Arseniatos/isolamento & purificação , Hidróxido de Magnésio/química , Purificação da Água/métodos , Adsorção , Ânions , Arseniatos/química , Arsênio/química , Concentração de Íons de Hidrogênio , Resinas de Troca Iônica/química , Modelos Teóricos , Fosfatos/química , Pós , Propriedades de Superfície , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
3.
J Endocrinol Invest ; 32(5): 395-400, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19794286

RESUMO

BACKGROUND: In the adiponectin gene polymorphisms, single-nucleotide polymorphism (SNP)-45 and SNP276 have reportedly been associated with obesity, Type 2 diabetes, and other features of metabolic syndrome. AIM: Whether these adiponectin SNP affect obesity-related parameters during caloric restriction in obese subjects. SUBJECTS AND METHODS: Thirty- two obese Japanese women were treated by meal replacement with a low calorie diet for 8 weeks and asked to maintain their habitual lifestyle. Obesity-related parameters were measured before and after the treatment period. We determined four SNP (T45G, I164T, G276T, and C-11377G) using a fluorescent allele-specific DNA primer assay systemand FRET probe assay system. RESULTS: After the treatment, the extent of decrease in waist circumference was greater in the subjects with the G/G or G/T genotype of SNP276 than in those with the T/T genotype (p=0.026). As for SNP45, the extent of decrease in triglyceride levels was greater in the subjects with the T/T genotype than in those with the T/G genotype (p=0.003). For SNP-11377, the extent of decrease in systolic blood pressure and fasting plasma glucose was greater in the subjects with the C/G or G/G genotype than in those with the C/C genotype (p=0.044). CONCLUSION: Our findings indicate that each SNP in the adiponectin gene might modify the change in obesity-related parameters during meal replacement with a low calorie diet.


Assuntos
Obesidade/dietoterapia , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adiponectina/genética , Adulto , Dieta Redutora , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento , Circunferência da Cintura/genética
4.
Protein Pept Lett ; 15(9): 931-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18991769

RESUMO

Mastoparan, a toxic peptide from wasp venom, induces various biological functions including histamine release from rat peritoneal mast cells. Here we report that, for the activation of mast cells by mastoparan, at least two positively charged side chains are required on the hydrophilic side of the amphiphilic structure of the peptide. The present results are expected to be utilized for the bioinformatic and comprehensive identification of endogenous mast cell-stimulating cryptides.


Assuntos
Exocitose , Mastócitos/citologia , Mastócitos/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Venenos de Vespas/química , Venenos de Vespas/farmacologia , Animais , Cromatografia Líquida de Alta Pressão , Interações Hidrofóbicas e Hidrofílicas , Peptídeos e Proteínas de Sinalização Intercelular , L-Lactato Desidrogenase , Masculino , Peptídeos/síntese química , Cavidade Peritoneal/citologia , Conformação Proteica , Ratos , Ratos Wistar , Análise de Sequência de Proteína , Relação Estrutura-Atividade , beta-N-Acetil-Hexosaminidases/metabolismo
5.
Heart ; 94(3): 316-21, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17591648

RESUMO

BACKGROUND: Arachidonic acid (ARA) and docosahexaenoic acid (DHA) are important components of phospholipids and cell membranes. There has, however, been no clinical report on the direct effects of ARA and DHA on coronary circulation. OBJECTIVE: To evaluate the effects of ARA and DHA on coronary circulation using the measurement of coronary flow velocity reserve (CFVR) by transthoracic Doppler echocardiography (TTDE). METHODS: A double-blind, placebo-matched study of 28 Japanese elderly individuals (19 men, mean age 65 years) conducted to compare the effects of polyunsaturated fatty acids (PUFA; ARA 240 mg/day, DHA 240 mg/day) and placebo on CFVR. Coronary flow velocity (CFV) of the left anterior descending coronary artery was measured at rest and during hyperaemia by TTDE to determine CFVR. RESULTS: There were no significant differences in CFV at rest or during hyperaemia in CFVR at baseline in the two groups (PUFA versus placebo 17 (7 SD) versus 16 (6), 62 (20) versus 59 (12), and 3.85 (1.04) versus 3.98 (0.83) cm/s, respectively). After three months' supplementation, CFV during hyperaemia was significantly higher in the PUFA than in the placebo group (73 (19) versus 64 (12) cm/s, p<0.01) although no significant difference was found between the two groups in CFV at rest (17 (7) versus 16 (4) cm/s). CFVR thus significantly increased after PUFA consumption (3.85 (1.04) versus 4.46 (0.95), p = 0.0023). CONCLUSION: Three months' supplementation of PUFA increased CFVR in Japanese elderly individuals, which suggests beneficial effects of PUFA on the coronary microcirculation.


Assuntos
Ácido Araquidônico/farmacologia , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Circulação Coronária/efeitos dos fármacos , Vasos Coronários/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Circulação Coronária/fisiologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/fisiologia , Ecocardiografia/métodos , Ecocardiografia Doppler em Cores/métodos , Métodos Epidemiológicos , Membrana Eritrocítica/diagnóstico por imagem , Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/fisiologia , Feminino , Humanos , Masculino
6.
Lipids ; 43(1): 37-43, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17985168

RESUMO

Disorders of the metabolism of essential fatty acids (EFAs) are related to atopic dermatitis (AD). Concentrations of dihomo-gamma-linolenic acid (DGLA), an EFA, in the serum of AD patients are lower than those in healthy volunteers. Recently we developed a fermented DGLA oil, and examined whether oral administration of DGLA prevents development of dermatitis in NC/Nga mice, which spontaneously develop human AD-like skin lesions. NC/Nga mice were fed a diet either containing or not containing DGLA for 8 weeks under in air-uncontrolled conventional circumstances. Clinical skin severity scores were significantly lower in mice fed DGLA than in mice not fed it. Scratching behavior and plasma total IgE levels were also reduced in the DGLA group, in association with histological improvement. DGLA suppressed clinical severity of skin lesions dose-dependently, with an increase in DGLA contents in phospholipids of skin, spleen, and plasma. Discontinuation of DGLA administration resulted in the onset of dermatitis and a decrease in DGLA contents in skin, spleen, and plasma. These findings indicate that oral administration of DGLA effectively prevents the development of AD in NC/Nga mice, and that DGLA in phospholipids is a compound of key importance in the development and prevention of dermatitis.


Assuntos
Ácido 8,11,14-Eicosatrienoico/administração & dosagem , Dermatite Atópica/prevenção & controle , Administração Oral , Animais , Dieta , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Imunoglobulina E/sangue , Masculino , Camundongos , Camundongos Endogâmicos , Índice de Gravidade de Doença , Pele/efeitos dos fármacos , Pele/patologia , Testes Cutâneos
7.
Anat Histol Embryol ; 36(2): 157-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17371391

RESUMO

To clarify the mechanism of implantation, relationship between positioning of the mouse embryo in the uterus and distribution of uterine glands along the long axis of the uterine horn was examined by three-dimensional remodelling of the uterine endometrium. There were two unique regions in the endometrium. Uterine glands were distributed widely from mesometrial to anti-mesometrial side in one region. It was localized from lateral to anti-mesometrial side in another. These different regions were alternately aligned throughout the uterine horn. The number and position of embryos was consistent with that of the latter region. This study suggests that the type of distribution of uterine glands is closely related to the positioning of the embryo in mice.


Assuntos
Camundongos/anatomia & histologia , Camundongos/embriologia , Prenhez/fisiologia , Útero/anatomia & histologia , Animais , Decídua/anatomia & histologia , Desenvolvimento Embrionário/fisiologia , Endométrio/anatomia & histologia , Feminino , Camundongos Endogâmicos ICR , Gravidez
8.
Eur J Clin Nutr ; 60(11): 1330-6, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16804556

RESUMO

OBJECTIVE: To assess possibility of polyphenol-enriched oolong tea to reduce dietary lipid absorption in humans. DESIGN: Twelve healthy adult subjects, three males and nine females, aged (mean+/-s.d.) 22.0+/-1.8 years, respectively, were randomly divided into two groups. The participants were followed a double-blind placebo-controlled crossover design, including 7-day washout periods and 10-day treatment periods. During the treatment periods, subjects were given about 38 g of lipids from potato chips (19 g each within 30 min after lunch and dinner) and total 750 ml beverages (placebo- or polyphenol-enriched oolong tea) at three meals. Blood samples were collected for biochemical examination at days 8, 18, 25 and 35 of the study period. On the last 3 days of each treatment period, feces were collected to measure the excretion of lipids. RESULTS: Lipid excretion into feces was significantly higher in the polyphenol-enriched oolong tea period (19.3+/-12.9 g/3 day) than in the placebo period (9.4+/-7.3 g/3 day) (P < 0.01). Cholesterol excretion tended to increase in polyphenol-enriched oolong tea period (1.8+/-1.2 g/3 day) compared with that of placebo (1.2+/-0.6 g/3 day) (P = 0.056). CONCLUSIONS: The results of this study indicated that polyphenol-enriched oolong tea could increase lipid excretion into feces when subjects took high-lipid diet.


Assuntos
Gorduras na Dieta/farmacocinética , Fezes/química , Flavonoides/farmacologia , Absorção Intestinal/efeitos dos fármacos , Lipídeos/análise , Fenóis/farmacologia , Chá , Adulto , Colesterol/análise , Colesterol/metabolismo , Estudos Cross-Over , Gorduras na Dieta/administração & dosagem , Método Duplo-Cego , Feminino , Alimentos Fortificados , Humanos , Hipercolesterolemia/dietoterapia , Masculino , Obesidade/dietoterapia , Polifenóis
9.
Water Sci Technol ; 50(8): 125-33, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15566195

RESUMO

Small-scale wastewater treatment facilities play an important role in improving the aquatic environment in many countries. Although sludge treatment is essential for overall wastewater treatment, it is difficult for small-scale facilities to use mechanical equipment or other facilities. As the first step of the sludge treatment, it is important to develop a convenient sludge thickening process for small-scale facilities. In this work, we examined the sludge thickening performance of a mesh filtration system: the mesh opening sizes of 100-500 microm, and the sludge (3,000-9,000 mg-SS/L) was obtained from a domestic wastewater treatment facility. The filtration was carried out only under the hydraulic pressure between the water level and the effluent port connected to the mesh filter module. The sludge reduction rates were in the range of 85-95% for 6-7 h; the initial filtration rate was very high, but the rate decreased with a decrease in hydraulic pressure due to the reduction of the water level in the vessel. In addition, the effluents (passed through the mesh) contained very low SS and could be directly discharged into the environment.


Assuntos
Filtração/métodos , Esgotos/química , Purificação da Água/métodos , Arquitetura de Instituições de Saúde , Tamanho da Partícula , Pressão , Eliminação de Resíduos Líquidos/métodos
10.
Int J Sports Med ; 24(7): 530-4, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12968212

RESUMO

To investigate the mechanism of antioxidative effects of sesamin in vivo, 32 male ddY mice were administered with 10 mg/kg or 100 mg/kg of sesamin (S10, S100), 100 mg/kg of vitamin E (VE100) or control sample (C). They were subjected to 30 min of swimming exercise 2 h after the sample administration by using a new forced-swimming apparatus, i. e. an adjustable-current swimming pool. Exercise resulted in a significant increase in plasma lipid peroxides (LPO) in C and VE100 (p < 0.01), but not in S10 and S100. S100 showed significantly higher total glutathione peroxidase activity and glutathione S-transferase activity in liver compared to C (p < 0.05). In conclusion, sesamin may enhance LPO degradation in the liver resulting in the strong protective effects against exercise-induced plasma lipid peroxidation.


Assuntos
Antioxidantes/farmacologia , Dioxóis/farmacologia , Glutationa Peroxidase/metabolismo , Lignanas/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Peróxidos Lipídicos/sangue , Condicionamento Físico Animal , Animais , Ativação Enzimática , Humanos , Masculino , Camundongos
11.
Acta Crystallogr C ; 57(Pt 11): 1333-5, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11706266

RESUMO

Kynostatin [KNI-272; systematic name: 3-[3-benzyl-2-hydroxy-9-(isoquinolin-5-yloxy)-6-methylsulfanylmethyl-5,8-dioxo-4,7-diazanonanoyl]-N-tert-butyl-1,3-thiazolane-4-carboxamide], a highly selective and potent HIV protease inhibitor containing allophenylnorstatin [(2S,3S)-3-amino-2-hydroxy-4-phenylbutyric acid], has been crystallized as the hydrate, C(33)H(41)N(5)O(6)S(2) x 0.803H(2)O, from aqueous hexylene glycol. The observed disorder of the phenyl group in the structure is related to the mode of hydration. The backbone conformation of the molecule is twisted and the overall conformation of the free inhibitor is similar to that observed in its complex with HIV protease.


Assuntos
Oligopeptídeos/química , Inibidores de Proteases/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular
12.
Nucl Med Biol ; 28(7): 761-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11578896

RESUMO

The effect of molecular charges on renal accumulation of 111In-DTPA-labeled low molecular weight (LMW) peptides was investigated using 111In-DTPA-octreotide derivatives as models to design radiolabeled peptides that are taken up less by renal cells. The N-terminal D-phenylalanine (Phe) of 111In-DTPA-D-Phe(1)-octreotide was replaced with L-aspartic acid (Asp), L-lysine (Lys), L-methionine (Met) or L-Phe. Cellulose acetate electrophoresis indicated that both 111In-DTPA-L-Phe(1)-octreotide and 111In-DTPA-L-Met(1)-octreotide showed similar net charges, whereas 111In-DTPA-L-alphaLys(1)-octreotide and 111In-DTPA-L-Asp(1)-octreotide had more positive and negative charges, respectively, at pH values similar to those in blood and glomerular filtrate. When injected into mice, significant differences were observed in the renal radioactivity levels. 111In-DTPA-L-alphaLys(1)-octreotide showed the highest radioactivity levels from 10 min to 6 h postinjection, whereas the lowest radioactivity levels were observed with 111In-DTPA-L-Asp(1)-octreotide at all the postinjection intervals. These findings indicated that the replacement of only one amino acid in 111In-DTPA-D-Phe(1)-octreotide significantly altered net molecular charges of the resulting peptides and that the net charges of the 111In-DTPA-octreotide derivatives significantly affected their renal uptake. Thus, an increase of negative charges in peptide molecules may constitute a strategy for designing 111In-DTPA-conjugated LMW peptides with low renal radioactivity levels.


Assuntos
Rim/metabolismo , Ácido Pentético/farmacocinética , Peptídeos/farmacocinética , Animais , Marcação por Isótopo , Masculino , Camundongos , Peso Molecular , Octreotida/química , Octreotida/farmacocinética , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/farmacocinética , Distribuição Tecidual
13.
Neurosci Lett ; 313(1-2): 78-82, 2001 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11684344

RESUMO

Effects of a chicken essence and one of its components, L-carnosine, on the hyperglycemia caused by intracranial injection of 2-deoxy-D-glucose (2DG-hyperglycemia) in unanesthetized rats were examined. The chicken essence inhibited the 2DG-hyperglycemia. Central or peripheral administration of specific doses of L-carnosine reduced the 2DG-hyperglycemia. L-carnosine inhibited neural activities of sympathetic efferent nerves innervating the adrenal gland and liver and facilitated the activity of vagal celiac nerve innervating the pancreas in urethane anesthetized rats. Specific doses of histamine also suppressed the 2DG-hyperglycemia, and thioperamide eliminated the inhibiting actions of both histamine and L-carnosine on the 2DG-hyperglycemia. Considering mammalian muscles contain L-carnosine, these facts suggest a possibility that L-carnosine might be an endogenous control factor of the blood glucose level through autonomic nerves via H3-receptor.


Assuntos
Carnosina/farmacologia , Hiperglicemia/tratamento farmacológico , Glândulas Suprarrenais/inervação , Animais , Antimetabólitos , Plexo Celíaco/efeitos dos fármacos , Plexo Celíaco/metabolismo , Desoxiglucose , Glucose/metabolismo , Histamina/farmacologia , Antagonistas dos Receptores Histamínicos/farmacologia , Hiperglicemia/induzido quimicamente , Masculino , Pâncreas/inervação , Piperidinas/farmacologia , Produtos Avícolas , Ratos , Ratos Wistar , Receptores Histamínicos H3/metabolismo
14.
Biol Pharm Bull ; 24(10): 1181-4, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11642328

RESUMO

We investigated the antihypertensive effect of Brand's Essence of Chicken (BEC), a popular chicken extract used as a traditional remedy, using deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Animals were unilaterally nephrectomized, and then separated into a sham-operated group (sham group) and a DOCA-salt-treated group. The latter was further separated into a normal diet group and a BEC (freeze-dried powder, 0.1 w/w%)-containing diet group. Systolic blood pressure of the normal diet group progressively increased in comparison with that of the sham group. The DOCA-salt-induced hypertension was markedly suppressed by feeding a BEC-containing diet. Systolic blood pressure after 5 weeks was 128+/-2 mmHg in sham group, 181+/-4 mmHg in the DOCA-salt-treated normal diet group and 139+/-5 mmHg in the DOCA-salt-treated BEC diet group, respectively. The treatment with DOCA and salt for 5 weeks significantly increased the weights of heart and left ventricle, but these increases were significantly suppressed in the BEC group. When the degree of vascular hypertrophy of the aorta was histochemically evaluated, DOCA-salt-induced increases in wall thickness and wall area of the vessels were significantly decreased by the BEC-feeding. Histopathological renal damage of fibrinoid-like necrosis in glomeruli, thickening of small arteries and tubular dilatation were observed in the DOCA-salt-treated normal diet group, but this damage was efficiently reduced by the BEC-feeding. In addition, BEC-feeding decreased urinary excretion of protein, which was elevated by the treatment with DOCA and salt. Thus, BEC seems to be useful as a prophylactic treatment in the development of hypertension and related tissue injuries.


Assuntos
Anti-Hipertensivos/farmacologia , Galinhas/fisiologia , Desoxicorticosterona , Hipertensão/prevenção & controle , Extratos de Tecidos/farmacologia , Animais , Aorta Torácica/patologia , Peso Corporal/efeitos dos fármacos , Cardiomegalia/etiologia , Cardiomegalia/patologia , Cardiomegalia/prevenção & controle , Hipertensão/induzido quimicamente , Hipertensão/patologia , Nefropatias/etiologia , Nefropatias/patologia , Nefropatias/prevenção & controle , Masculino , Tamanho do Órgão/efeitos dos fármacos , Proteinúria/prevenção & controle , Ratos , Ratos Sprague-Dawley
15.
Biosci Biotechnol Biochem ; 65(9): 2083-6, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11676025

RESUMO

Resting energy expenditure (REE) values after consuming chicken essence tablets were significantly higher than those observed after consuming skim milk protein tablets (control trial). The increased thermogenic effects continued at least for a period of one hour and gradually decreased towards the baseline. The REE values during control treatment did not show such an augmented response.


Assuntos
Metabolismo Basal , Medicina Tradicional Chinesa , Administração Oral , Adulto , Animais , Alimentos , Humanos , Masculino , Comprimidos/administração & dosagem , Termogênese
16.
Bioorg Med Chem Lett ; 11(18): 2465-8, 2001 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-11549448

RESUMO

To inhibit the HIV-1 protease dimerization necessary to exhibit enzymatic activity, we synthesized and evaluated a new beta-sheet peptide (compound 1), containing 4-(2-aminoethyl)-6-dibenzofuranpropionic acid as a conformationally restricted linker and a non-peptidic beta-strand mimetic, 2-[3-([2-[(9-fluorenylmethoxy)carbonyl]hydrazino]carbonyl)-4-methoxyanilino]-2-oxoacetic acid (Fmoc-Hao-OH, compound 2). Kinetic analysis showed that compound 1 inhibited the dimerization of HIV-1 protease by a dissociative mechanism with a K(id) value of 5.4 microM at 37 degrees C (pH 5.0). However, compound 2 showed a small shift in the slope of the lines in the Zhang-Poorman plot (K(id)=9.1 microM), suggesting that compound 2 inhibits the dimerization of HIV-1 PR not only through a dissociative mechanism but also through an active-site directed mechanism partly. This is the first study of a non-peptidic inhibitor of HIV-1 protease dimerization.


Assuntos
Inibidores da Protease de HIV/química , Inibidores da Protease de HIV/farmacologia , Protease de HIV/efeitos dos fármacos , Hidrazinas/síntese química , Hidrazinas/farmacologia , Dimerização , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Protease de HIV/química , Protease de HIV/metabolismo , Inibidores da Protease de HIV/síntese química , Cinética , Conformação Molecular , Mimetismo Molecular , Relação Estrutura-Atividade
17.
Prostaglandins Other Lipid Mediat ; 66(2): 109-20, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11534547

RESUMO

Several studies have shown that dietary n-3 polyunsaturated fatty acids (PUFAs) suppress platelet-activating factor (PAF) generation in leukocytes of humans and rodents, which is associated with the antagonism of arachidonic acid metabolism. Dietary eicosatrienoic acid (20:3n-9, ETrA) is also suggested to antagonize arachidonic acid (AA) metabolism, but its effect on PAF generation in leukocytes has not been defined. In the present study, we investigated the effects of an ETrA-rich diet on PAF generation and AA metabolism in mouse peritoneal cells, which were compared with those of a docosahexaenoic acid (DHA)-rich diet. Mice were fed a diet supplemented with a lipid preparation rich in ETrA, a DHA-rich fish oil (FO) or palm oil (PO) for 3 weeks, and peritoneal cells containing more than 80% of monocytes/macrophages were obtained. The peritoneal cells in the DHA and ETrA diet groups generated upon zymosan stimulation a smaller amount of PAF than cells in the PO diet group. In the peritoneal cells of the DHA diet group, AA contents in phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were significantly lower than those in cells of the PO diet group, but those in phosphatidylinositol (PI) were not significantly different between the two dietary groups. A considerable amount of ETrA was incorporated into the peritoneal cells of the ETrA diet group, and AA was reduced as compared with the PO diet group. These changes occurred preferentially in PI but to a less extent in PC and PE. The amount of free AA released by the peritoneal cells upon zymosan stimulation was significantly reduced in the DHA diet group as compared with that in the PO diet group, whereas AA release was similar between the PO and ETrA diet groups. In conclusion, the effects of dietary ETrA on AA content in the phospholipid subclasses and AA release were quite different from those of dietary DHA, although both diets suppressed PAF generation in mouse peritoneal cells to a similar extent.


Assuntos
Ácidos Araquidônicos/metabolismo , Ácidos Graxos Insaturados/administração & dosagem , Peritônio/metabolismo , Fator de Ativação de Plaquetas/antagonistas & inibidores , Animais , Contagem de Leucócitos , Masculino , Camundongos , Lavagem Peritoneal , Peritônio/citologia , Fosfolipídeos/metabolismo , Fator de Ativação de Plaquetas/biossíntese
18.
J Org Chem ; 66(16): 5537-44, 2001 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-11485480

RESUMO

In the synthesis of peptidomimetics containing alpha-hydroxy-beta-amino acid, the coupling of this N(beta)-protected beta-amino acid with amine components was generally performed without the protection of its alpha-hydroxyl group. However, the formation of dipeptides in low yield was often observed when sterically hindered amine components were used. Boc-Apns-OH [Apns: (2S,3S)-3-amino-2-hydroxy-4-phenylbutanoic acid, allophenylnorstatine] (6), which is one of such beta-amino acid derivatives, is intensively employed as a core structure in the development of HIV-1 protease inhibitors. There have been no precise studies, to date, that have examined amide bond formation with alpha-hydroxy-beta-amino acid derivatives as an acyl component. To determine the cause of this low-yield reaction, we studied the amide bond formation focusing on the activation step of N(beta)-protected alpha-hydroxy-beta-amino acid by using a model coupling reaction between 6 and H-Dmt-OR [Dmt: (R)-5,5-dimethyl-1,3-thiazolidine-4-carboxylic acid] (7). A significant amount of homobislactone 9 was formed through the activation of the carboxyl group of 6 to the benzotriazole-type active esters such as OBt and OAt. In addition, this homobislactone formation was markedly increased in the presence of a catalytic amount of a base, which exhibited good correlation with the low yield of the amide bond formation, suggesting that homobislactone formation is one major reason for the low yield of the amide bond formation. Moreover, homobislactones were also formed in other derivatives of the N(beta)-protected alpha-hydroxy-beta-amino acid, suggesting a common feature of this type of amino acids. The use of a strong activation method like EDC--HOAt without base addition enhanced amide bond formation, although a small amount of homobislactone may be formed during the coupling reaction.


Assuntos
Lactonas/síntese química , Fenilbutiratos/química , Inibidores de Proteases/síntese química , Aminocaproatos/química , Cromatografia Líquida de Alta Pressão , Lactonas/química , Lactonas/farmacologia , Fenilbutiratos/farmacologia , Inibidores de Proteases/química
19.
Exp Hematol ; 29(7): 803-11, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11438202

RESUMO

OBJECTIVE: Interleukin-3 (IL-3) and stem cell factor (SCF) are able to promote survival and proliferation of mast cells. However, the precise signal transduction cascades leading to mast cell proliferation are not clearly understood. Thus, we sought to define the mechanism of mast cell proliferation induced by IL-3 and SCF. MATERIALS AND METHODS: We treated murine bone marrow-derived cultured mast cells (BMCMC) with recombinant IL-3 (rIL-3) or recombinant SCF (rSCF) and examined the effects of rIL-3 and rSCF on cell cycle regulatory factors. RESULTS: Both rIL-3 and rSCF suppressed apoptosis of BMCMC. rSCF induced great proliferation of BMCMC with elevation of the proportions of cells in S and G2/M phases, whereas most BMCMC incubated with rIL-3 were arrested in the G1 phase. The G1/S phase transition is initiated by phosphorylated retinoblastoma protein (pRb), which was prominent in cells stimulated with rSCF. In contrast, rIL-3 relatively increased a dephosphorylated form of pRb in BMCMC. Compared with rIL-3, rSCF induced greater expression of cyclin-dependent kinase (CDK) 2 and CDK4, which are able to phosphorylate pRb, and cyclin D3, a partner of CDK4. BMCMC treated with rIL-3 contained a high amount of a CDK inhibitor p27Kip1 that was suppressed by pretreatment with Ro31-7549, a protein kinase C inhibitor, whereas rSCF induced weak expression of p27Kip1 in BMCMC. CONCLUSION: The results suggest that IL-3 and SCF exert their respective mitogenic effects on mast cells by modulating the expression of pRb, CDK, cyclin, and p27Kip1.


Assuntos
Ciclo Celular/efeitos dos fármacos , Interleucina-3/farmacologia , Mastócitos/citologia , Mastócitos/fisiologia , Fator de Células-Tronco/farmacologia , Proteínas Supressoras de Tumor , Animais , Ciclo Celular/fisiologia , Proteínas de Ciclo Celular/fisiologia , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p27 , Camundongos , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos
20.
Bioorg Med Chem ; 9(6): 1589-600, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11408178

RESUMO

Based on the prodrug concept as well as the combination of two different classes of anti-HIV agents, we designed and synthesized a series of anti-HIV double-drugs consisting of HIV protease inhibitors conjugated with a nucleoside reverse transcriptase inhibitor in an effort to enhance the antiviral activity. For the conjugation, a series of linkers that conjoins the two different classes of inhibitors has been investigated. Double-drugs using a succinyl amino acid linker were shown to release the parent drugs via spontaneous imide formation at a faster rate compared to compounds using a glutaryl amino acid linker, as expected from the energetically favorable cyclization to the five-membered ring. Among the double-drugs, KNI-1039 (3b) with a glutarylglycine linker exhibited extremely potent anti-HIV activity compared with that of the individual components. Double-drug 3b was relatively stable in culture medium, whereas it regenerated active species in cell homogenate. These results suggested that the synergistic enhancement of anti-HIV activities of 3b may be due to their ability to penetrate into the target cell and subsequent regeneration of two different classes of anti-HIV agents in the cytoplasm.


Assuntos
Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Inibidores da Protease de HIV/química , Inibidores da Protease de HIV/farmacologia , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/farmacologia , Animais , Fármacos Anti-HIV/síntese química , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores da Protease de HIV/síntese química , Humanos , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Inibidores da Transcriptase Reversa/síntese química , Relação Estrutura-Atividade , Tiazóis/química , Tiazóis/farmacologia , Células Tumorais Cultivadas/virologia , Zidovudina/química , Zidovudina/farmacologia
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