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1.
Br J Cancer ; 86(6): 924-8, 2002 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-11953825

RESUMO

Squamous cell carcinoma of the vulva is a disease of significant clinical importance, which arises in the presence or absence of human papillomavirus. We used comparative genomic hybridisation to document non-random chromosomal gains and losses within human papillomavirus positive and negative vulvar cancers. Gain of 3q was significantly more common in human papillomavirus-positive cancers compared to human papillomavirus-negative cancers. The smallest area of gain was 3q22-25, a chromosome region which is frequently gained in other human papillomavirus-related cancers. Chromosome 8q was more commonly gained in human papillomavirus-negative compared to human papillomavirus-positive cancers. 8q21 was the smallest region of gain, which has been identified in other, non-human papillomavirus-related cancers. Chromosome arms 3p and 11q were lost in both categories of vulvar cancer. This study has demonstrated chromosome locations important in the development of vulvar squamous cell carcinoma. Additionally, taken together with previous studies of human papillomavirus-positive cancers of other anogenital sites, the data indicate that one or more oncogenes important in the development and progression of human papillomavirus-induced carcinomas are located on 3q. The different genetic changes seen in human papillomavirus-positive and negative vulvar squamous cell carcinomas support the clinicopathological data indicating that these are different cancer types.


Assuntos
Carcinoma de Células Escamosas/genética , Aberrações Cromossômicas , Hibridização de Ácido Nucleico/métodos , Papillomaviridae/isolamento & purificação , Neoplasias Vulvares/genética , Carcinoma de Células Escamosas/virologia , Feminino , Humanos , Perda de Heterozigosidade , Neoplasias Vulvares/virologia
2.
Nutr Cancer ; 39(1): 58-65, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11588903

RESUMO

Lignans, similar in structure to endogenous sex steroid hormones, may act in vivo to alter hormone metabolism and subsequent cancer risk. The objective of this study was to examine effects of dietary intake of a lignan-rich plant food (flaxseed) on serum concentrations of endogenous hormones and binding proteins (estrone, estrone sulfate, 17 beta-estradiol, sex hormone-binding globulin, progesterone, prolactin, dehydroepiandrosterone sulfate, dehydroepiandrosterone, androstenedione, testosterone, and free testosterone) in postmenopausal women. This randomized, crossover trial consisted of three seven-week feeding periods, during which 28 postmenopausal women, aged 52-82 yr, consumed their habitual diets plus 0, 5, or 10 g of ground flaxseed. Serum samples collected during the last week of each feeding period were analyzed for serum hormones using standard diagnostic kits. The flaxseed diets significantly reduced serum concentrations of 17 beta-estradiol by 3.26 pg/ml (12.06 pmol/l) and estrone sulfate by 0.09 ng/ml (0.42 nmol/l) and increased prolactin by 1.92 micrograms/l (0.05 IU/ml). Serum concentrations of androstenedione, estrone, sex hormone-binding globulin, progesterone, testosterone, free testosterone, dehydroepiandrosterone, and dehydroepiandrosterone sulfate were not altered with flaxseed feeding. In this group of postmenopausal women, consuming flaxseed in addition to their habitual diets influenced their endogenous hormone metabolism by decreasing serum 17 beta-estradiol and estrone sulfate and increasing serum prolactin concentrations.


Assuntos
Estrona/análogos & derivados , Linho/metabolismo , Hormônios/sangue , Lignanas/metabolismo , Pós-Menopausa/sangue , Idoso , Idoso de 80 Anos ou mais , Estudos Cross-Over , Estradiol/sangue , Estrona/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa/metabolismo , Prolactina/sangue
4.
J Bacteriol ; 183(2): 709-15, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11133966

RESUMO

Phosphoenolpyruvate synthetase (PpsA) was purified from the hyperthermophilic archaeon Pyrococcus furiosus. This enzyme catalyzes the conversion of pyruvate and ATP to phosphoenolpyruvate (PEP), AMP, and phosphate and is thought to function in gluconeogenesis. PpsA has a subunit molecular mass of 92 kDa and contains one calcium and one phosphorus atom per subunit. The active form has a molecular mass of 690+/-20 kDa and is assumed to be octomeric, while approximately 30% of the protein is purified as a large ( approximately 1.6 MDa) complex that is not active. The apparent K(m) values and catalytic efficiencies for the substrates pyruvate and ATP (at 80 degrees C, pH 8.4) were 0.11 mM and 1.43 x 10(4) mM(-1). s(-1) and 0.39 mM and 3.40 x 10(3) mM(-1) x s(-1), respectively. Maximal activity was measured at pH 9.0 (at 80 degrees C) and at 90 degrees C (at pH 8.4). The enzyme also catalyzed the reverse reaction, but the catalytic efficiency with PEP was very low [k(cat)/K(m) = 32 (mM. s(-1)]. In contrast to several other nucleotide-dependent enzymes from P. furiosus, PpsA has an absolute specificity for ATP as the phosphate-donating substrate. This is the first PpsA from a nonmethanogenic archaeon to be biochemically characterized. Its kinetic properties are consistent with a role in gluconeogenesis, although its relatively high cellular concentration ( approximately 5% of the cytoplasmic protein) suggests an additional function possibly related to energy spilling. It is not known whether interconversion between the smaller, active and larger, inactive forms of the enzyme has any functional role.


Assuntos
Fosfotransferases (Aceptores Pareados)/metabolismo , Pyrococcus furiosus/enzimologia , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Gluconeogênese , Concentração de Íons de Hidrogênio , Fosfatos/metabolismo , Fosfoenolpiruvato/metabolismo , Fosfotransferases (Aceptores Pareados)/isolamento & purificação , Ácido Pirúvico/metabolismo , Especificidade por Substrato
5.
J Bacteriol ; 183(2): 716-24, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11133967

RESUMO

The hyperthermophilic archaeon Pyrococcus furiosus grows optimally at 100 degrees C by the fermentation of peptides and carbohydrates. Growth of the organism was examined in media containing either maltose, peptides (hydrolyzed casein), or both as the carbon source(s), each with and without elemental sulfur (S(0)). Growth rates were highest on media containing peptides and S(0), with or without maltose. Growth did not occur on the peptide medium without S(0). S(0) had no effect on growth rates in the maltose medium in the absence of peptides. Phenylacetate production rates (from phenylalanine fermentation) from cells grown in the peptide medium containing S(0) with or without maltose were the same, suggesting that S(0) is required for peptide utilization. The activities of 14 of 21 enzymes involved in or related to the fermentation pathways of P. furiosus were shown to be regulated under the five different growth conditions studied. The presence of S(0) in the growth media resulted in decreases in specific activities of two cytoplasmic hydrogenases (I and II) and of a membrane-bound hydrogenase, each by an order of magnitude. The primary S(0)-reducing enzyme in this organism and the mechanism of the S(0) dependence of peptide metabolism are not known. This study provides the first evidence for a highly regulated fermentation-based metabolism in P. furiosus and a significant regulatory role for elemental sulfur or its metabolites.


Assuntos
Hidrogenase/metabolismo , Peptídeos/metabolismo , Pyrococcus furiosus/metabolismo , Enxofre/metabolismo , Meios de Cultura , Citoplasma/enzimologia , Regulação da Expressão Gênica em Archaea , Regulação Enzimológica da Expressão Gênica , Glicólise , Proteínas de Membrana/metabolismo , Oxirredução
6.
Br J Cancer ; 83(12): 1659-63, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11104563

RESUMO

Genetic changes orchestrated by human papillomaviruses are the most important known factors in carcinogenesis of the uterine cervix. However, it is clear that additional genetic events are necessary for tumour progression. We have used comparative genomic hybridization to document non-random chromosomal gains and losses within a subset of 37 cervical carcinomas matched for clinical stage Ib, but with different lymph node status. There were significantly more chromosomal changes in the primary tumours when the lymph nodes were positive for metastases. The most frequent copy number alterations were loss of 3p, 11q, 6q and 10q and gain of 3q. The smallest areas of loss and gain on chromosome 3 were 3p14-22 and 3q24-26. The study identifies progressive DNA copy number changes associated with early-stage invasive cervical cancers with and without lymph node metastases, a factor of potential prognostic and therapeutic value.


Assuntos
Carcinoma de Células Escamosas/genética , Aberrações Cromossômicas , Neoplasias do Colo do Útero/genética , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Cromossomos Humanos Par 10/genética , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 3/genética , Cromossomos Humanos Par 6/genética , Progressão da Doença , Feminino , Humanos , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico/métodos , Neoplasias do Colo do Útero/patologia
7.
Cancer Epidemiol Biomarkers Prev ; 9(10): 1113-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11045796

RESUMO

Dietary estrogens, such as lignans, are similar in structure to endogenous sex steroid hormones and may act in vivo to alter hormone metabolism and subsequent cancer risk. The objective of this study was to examine the effect of dietary intake of a lignan-rich plant food (flaxseed) on urinary lignan excretion in postmenopausal women. This randomized, cross-over trial consisted of three 7-week feeding periods during which 31 healthy postmenopausal women, ages 52-82 years, consumed their habitual diets plus 0, 5, or 10 grams of ground flaxseed per day. Urine samples collected for 2 consecutive days during the last week of each feeding period were analyzed for lignan content (enterodiol, enterolactone, and matairesinol) by isotope dilution gas chromatography/mass spectrometry. Compared with the 0-gram flaxseed diet, consumption of 5 or 10 grams of flaxseed significantly increased excretion of enterodiol by 1,009 and 2,867 nmol/day, respectively; significantly increased excretion of enterolactone by 21,242 and 52,826 nmol/day, respectively; and significantly increased excretion of total lignans (enterodiol + enterolactone + matairesinol) by 24,333 and 60,640 nmol/day, respectively. Excretion of matairesinol was not significantly altered by flaxseed consumption. Consumption of flax, a significant source of dietary estrogens, in addition to their habitual diets increased excretion of enterodiol and enterolactone, but not matairesinol, in a dose-dependent manner in this group of postmenopausal women. Urinary excretion of lignan metabolites is a dose-dependent biomarker of flaxseed intake within the context of a habitual diet.


Assuntos
Linho , Lignanas/urina , Pós-Menopausa , Idoso , Biomarcadores/análise , Estudos Cross-Over , Dieta , Relação Dose-Resposta a Droga , Feminino , Humanos , Pessoa de Meia-Idade
8.
Melanoma Res ; 10(3): 259-64, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10890380

RESUMO

MAGE proteins have been identified as potential specific targets for cancer vaccination. Although MAGE-6 and MAGE-12 were originally identified in malignant melanoma there are no studies reporting the frequency of expression of these antigens in this malignancy. These are of relevance particularly for MAGE-6 as recent studies have identified CTL activity against several epitopes. We have studied MAGE-1, -2, -3, -4, -6 and -12 gene expression using reverse transcription-polymerase chain reaction in 47 melanoma samples and 11 melanoma cell lines established from these tumours. The tumour samples expressed MAGE-12 (74%) and MAGE-6 (64%) mRNA at much higher frequencies than the other MAGE genes. MAGE-12 and MAGE-6 were expressed at the highest frequencies, relative to the other MAGE antigens, in early stage lesions. The frequency of expression of all the MAGE genes was found to be higher in samples from metastatic deposits compared to those from locoregional disease. The cell lines all expressed the same or more MAGE antigens than the tumours from which they were derived. In only one cell line was expression of a MAGE antigen lost. Certain recurring patterns of MAGE expression were observed in the tumour samples. MAGE-6 and/or -12 expression were detected in all of those 26 tumour samples that were positive for one or more of MAGE-1, -2, -3 and -4. Twenty of these 26 samples expressed both antigens. These findings suggest that protocols targeting MAGE-12 and -6 would permit many more patients to be included into clinical cancer vaccination trials.


Assuntos
Antígenos de Neoplasias/genética , Melanoma/metabolismo , Proteínas de Neoplasias/genética , RNA Mensageiro/biossíntese , Neoplasias Cutâneas/metabolismo , Adulto , Idoso , Antígenos de Neoplasias/biossíntese , Primers do DNA/química , Expressão Gênica , Humanos , Melanoma/genética , Melanoma/patologia , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Células Tumorais Cultivadas
9.
Nutr Cancer ; 33(2): 188-95, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10368815

RESUMO

Flaxseed, the richest known source of plant lignans, has been shown to have chemoprotective effects in animal and cell studies. Some of its effects may be mediated through its influence on endogenous hormone production and metabolism. Two competing pathways in estrogen metabolism involve production of the 2-hydroxylated and 16 alpha-hydroxylated metabolites. Because of the proposed differences in biological activities of these metabolites, the balance of the two pathways has been used as a biomarker for breast cancer risk. We examined the effects of flaxseed consumption on urinary estrogen metabolite excretion in postmenopausal women. Twenty-eight postmenopausal women were studied for three seven-week feeding periods in a randomized crossover design. During the feeding periods, subjects consumed their usual diets plus ground flaxseed (0, 5, or 10 g/day). Urinary excretion of the estrogen metabolites 2-hydroxyestrogen (2-OHEstrogen) and 16 alpha-hydroxyestrone (16 alpha-OHE1) as well as their ratio, 2/16 alpha-OHE1, was measured by enzyme immunoassay. Flaxseed supplementation significantly increased urinary 2-OHEstrogen excretion (p < 0.0005) and the urinary 2/16 alpha-OHE1 ratio (p < 0.05) in a linear, dose-response fashion. There were no significant differences in urinary 16 alpha-OHE1 excretion. These results suggest that flaxseed may have chemoprotective effects in postmenopausal women.


Assuntos
Estrogênios/urina , Linho , Lignanas/farmacologia , Pós-Menopausa , Sementes , Idoso , Idoso de 80 Anos ou mais , Estudos Cross-Over , Feminino , Humanos , Lignanas/administração & dosagem , Pessoa de Meia-Idade
10.
Cancer Res ; 59(8): 2011-7, 1999 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10213514

RESUMO

Breast cancers arising in women with and without a germline mutation in the BRCA1 or BRCA2 gene display different histological features, which suggests unique mechanisms of molecular pathogenesis: We used a molecular pathological analysis to define the genetic abnormalities relevant to these specific pathogeneses. Tumor material was studied from 40 women with breast cancer diagnosed before 40 years of age, sampled from a population-based study and stratified by BRCA1 and BRCA2 germline mutation status. Cases were not selected for family history or ethnic origin, and none were known to be genetically related. Thus, germline mutation itself is likely to impact on the molecular pathogenesis of these tumors, with no substantial influence due to modifying genetic or environmental factors. Breast cancers occurring in BRCA1 mutation carriers had significantly higher levels of p53 expression, including the preinvasive (carcinoma in situ) stage of disease, compared with cancers occurring in BRCA2 mutation carriers or women with no detectable germline mutation. These cancers also had a higher proliferation rate as measured by Ki-67 antibody. Expression of the prognostic factors c-erbB-2, cyclin D1, and estrogen receptor was significantly less common in BRCA1 mutation carriers. Lower levels of cyclin D1 were also found in cancers from BRCA2 mutation carriers compared with non-mutation carriers. Direct p53 mutation analysis revealed mutations in 18% of all of the early-onset breast cancers within the study and included rare insertion and deletional mutations in cancers from BRCA1 mutation carriers. Our data indicate that a BRCA1 breast cancer phenotype may be recognized by an exceptionally high proliferation rate and early and frequent p53 overexpression but infrequent selection for overexpression of several other prognostic factor proteins known to be involved in breast oncogenesis. In contrast, breast cancers arising in BRCA2 mutation carriers have a more heterogeneous phenotypic profile.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Proteínas de Neoplasias/genética , Fatores de Transcrição/genética , Idade de Início , Proteína BRCA2 , Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Feminino , Genética Populacional , Humanos , Imuno-Histoquímica , Perda de Heterozigosidade , Mutação , Invasividade Neoplásica/genética , Proteína Supressora de Tumor p53/genética
11.
Cancer Epidemiol Biomarkers Prev ; 8(8): 699-707, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10744130

RESUMO

Dietary isoflavone and lignan phytoestrogens are potential chemopreventive agents. This has led to a need to monitor exposure to these compounds in human populations and to determine which components of a mixed diet contribute to the exposure. Typically, urinary isoflavonoid excretion is associated with soy consumption and that of lignans is associated with whole grains. However, other plant foods are known to contain phytoestrogen precursors. The purpose of this study was to examine the association between urinary isoflavonoid and lignan excretion and intakes of vegetables and fruits (V&F). Isoflavonoids (genistein, daidzein, O-desmethylangolensin, and equol) and lignans (enterolactone, enterodiol, and matairesinol) were measured in urine collected for 3 days from 49 male and 49 female volunteers (age, 18-37 years) reporting a wide range of habitual V&F intakes. Dietary intakes were assessed using 5-day diet records and a food frequency questionnaire. V&F groupings (total V&F, total V, total F, soyfoods, and V&F grouped by botanical families) were used to assess the relationship between V&F intake and urinary isoflavonoid and lignan excretion. Pearson correlations were performed. Intake of soyfoods was correlated significantly with urinary genistein (r = 0.40; P = 0.0001), O-desmethylangolensin (r = 0.37; P = 0.0002), daidzein (r = 034; P = 0.0007), and the sum of isoflavonoids (r = 0.39; P = 0.0001). There was no association between equol excretion and soy intake or between the isoflavonoids and any other V&F groupings. In addition, isoflavonoid excretion was correlated positively with intake of high-fat and processed meats, particularly among men who did not consume soy. This suggests that, even in the United States, on a Western diet, soyfoods are the primary contributors to isoflavone intake; however, additional "hidden sources" of soy may also contribute to exposure. In contrast, a variety of fiber-containing foods contributed to lignan excretion; the sum of the urinary lignans, enterodiol, enterolactone, and matairesinol, was associated with intake of total F (r = 0.27; P = 0.008), total V&F (r = 0.25; P = 0.01), soyfoods (r = 0.28; P = 0.006), and dietary fiber (r = 0.36; P = 0.0003). Overall, urinary phytoestrogens (isoflavonoids + lignans) were significantly higher in "high" compared with "low" V&F consumers. Compared with the "low" V&F group, the "high" group consumed diets that were, on average, higher in fiber and carbohydrate and soyfoods and lower in fat; thus, the urinary phytoestrogens may also be a useful marker of healthier dietary patterns.


Assuntos
Frutas , Isoflavonas/urina , Lignanas/urina , Proteínas de Soja , Verduras , Adolescente , Adulto , Estudos Transversais , Fibras na Dieta , Feminino , Humanos , Masculino
12.
Am J Clin Nutr ; 68(6 Suppl): 1492S-1495S, 1998 12.
Artigo em Inglês | MEDLINE | ID: mdl-9848522

RESUMO

In an attempt to explain the wide individual variation seen in urinary isoflavonoid phytoestrogen excretion, we conducted a series of 3 human feeding studies: a large cross-sectional study of equol production in humans with a soy challenge, a comparison of phytoestrogen metabolism when subjects consumed fermented and unfermented soy products, and a dose-response study of urinary isoflavonoid excretion at the low end of soy consumption. All studies were conducted in young, healthy humans. Urinary isoflavonoids were measured by isotope-dilution gas chromatography-mass spectrometry. Similar to results from other studies, 35% of screened subjects (30 men and 30 women) excreted equol (>2000 nmol/d). In women, equol excretion was associated with higher intake of dietary fiber and carbohydrate. Fermentation of soy decreased the isoflavone content of the product fed but increased the urinary isoflavonoid recovery, suggesting that fermentation increases availability of isoflavones in soy. When soy-protein powder was fed at 0, 5, 10, and 20 g/d (0-36 mg isoflavones), there was a linear dose response of urinary isoflavonoid excretion to soy consumption that did not differ between subjects with high and low equol excretion. These results suggest that equol excretion may be related to the fermentable carbohydrate content of the diet; additional study is needed. Processing of soy affects isoflavone metabolism and must be considered in recommending exposure to isoflavones from soyfoods. Although optimal isoflavone exposure for disease protection has not been determined, urinary isoflavonoid excretion appears linear at low-to-moderate soy consumption.


Assuntos
Dieta , Manipulação de Alimentos , Isoflavonas/urina , Proteínas de Soja/administração & dosagem , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Isoflavonas/administração & dosagem , Isoflavonas/metabolismo , Isoflavonas/farmacocinética , Masculino
13.
Proc Soc Exp Biol Med ; 217(3): 335-9, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9492344

RESUMO

Equol is an isoflavonoid phytoestrogen produced from the soy isoflavone daidzein by gut microflora. Not all humans produce equol from daidzein, presumably due to differences in colonic bacterial populations among individuals. Previously, smaller studies reported that approximately 30% of participants excreted equol when consuming soy. The purpose of our study was to determine the prevalence of equol excreters in a larger sample and to examine what dietary components might influence the tendency to be an equol excreter. Thirty men and thirty women consumed a soy protein beverage containing 22 mg genistein and 8 mg daidzein for 4 days as a supplement to their habitual diets. The mean daily nutrient content of their habitual intakes was determined from 4-day food records. On Day 4, participants provided a 24-hour urine collection. Urinary isoflavonoid (genistein, daidzein, equol, and O-desmethylangolensin) excretion was measured by gas chromatography-mass spectrometry. Twenty-one of the 60 participants (35%) excreted equol (> 2000 nmol/day) after 3 days of consuming the soy supplement. Daily equol excretion ranged from 2,134-20,301 nmol/day in the excreters and 21-233 nmol/day in the nonexcreters. There was no difference in equol excreter prevalence between men (43%) and women (27%). Daily excretion of daidzein, genistein, and O-desmethylangolensin was similar between equol excreters and nonexcreters and between men and women. Among the women, equol excreters consumed a significantly higher percentage of energy as carbohydrate and greater amounts of plant protein and dietary fiber, both as soluble and insoluble fiber compared to nonexcreters. Such differences were not observed in the men, who overall had significantly higher fiber intakes than the women. These data suggest that, among women, dietary fiber or other components of a high-fiber diet may promote the growth and/or the activity of bacterial populations responsible for equol production in the colon.


Assuntos
Cromanos/urina , Fibras na Dieta/administração & dosagem , Comportamento Alimentar , Glycine max , Isoflavonas , Adulto , Equol , Feminino , Humanos , Masculino , Fatores Sexuais
14.
Am J Clin Nutr ; 66(1): 46-51, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9209168

RESUMO

Soybeans contain isoflavones, which have been associated with many health benefits, including decreased cancer risk. The purpose of our study was to measure urinary isoflavonoid excretion in response to daily consumption of soy that contained 0-36 mg isoflavones--a lower range than used in previous studies--and to compare urinary isoflavonoid excretion between equol excreters and nonexcreters. Fourteen men and women aged 20-40 y participated in the study. Half of the subjects were identified previously as equol excreters and the other half as equol nonexcreters. This randomized, double-blind, crossover study consisted of four 9-d diet treatment periods. During each treatment period participants consumed a low-photoestrogen controlled diet and a beverage containing 0, 5, 10, or 20 g soy protein. Urine collected on the last 3 d of each treatment period was analyzed for isoflavonoid (equol, O-desmethylangolensin, genistein, and daidzein) and lignan (enterodiol and enterolactone) contents by using isotope-dilution gas chromatography-mass spectrometry. There was a highly linear dose response of urinary isoflavonoid excretion to soy consumption, which did not differ significantly between equol excreters and nonexcreters. There were no significant differences in lignan excretion between the two diet treatments. Our results indicate that urinary isoflavonoid excretion is dose dependent in humans at low to moderate levels of soy consumption.


Assuntos
Isoflavonas/urina , Proteínas de Soja/metabolismo , Adulto , Estudos Cross-Over , Método Duplo-Cego , Estrogênios não Esteroides/urina , Feminino , Humanos , Masculino , Fitoestrógenos , Preparações de Plantas , Proteínas de Soja/administração & dosagem
15.
Biochim Biophys Acta ; 1309(1-2): 77-80, 1996 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-8950181

RESUMO

A novel human P2 nucleotide receptor has been cloned from a T-cell cDNA library. The predicted amino acid sequence shows characteristics of a G-protein-coupled receptor, and shares 88% homology with a recently characterised rat P2 nucleotide receptor sequence. Distinctive features include an extremely short cytoplasmic tail with only one putative protein kinase C phosphorylation site. Northern blot analysis revealed a 1.9 kb transcript expressed in the placenta.


Assuntos
DNA Complementar/genética , Receptores Purinérgicos P2/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Proteínas de Ligação ao GTP , Humanos , Dados de Sequência Molecular , Especificidade de Órgãos , RNA Mensageiro/análise , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Linfócitos T
16.
Hypertension ; 26(5): 828-34, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7591025

RESUMO

Abnormalities of the vasopressin system are found in genetic hypertension. This study compares the delayed effects of a brief period of vasopressin V1A receptor blockade and angiotensin-converting enzyme inhibition in young female and male spontaneously hypertensive rats (SHR) on the development of hypertension in adult life. In a separate study, the role of vasopressin in the maintenance of blood pressure in adult SHR was assessed. Young SHR received either the nonpeptide vasopressin V1A receptor antagonist OPC-21268, the angiotensin-converting enzyme inhibitor ramipril, or vehicle from 6 to 10 weeks of age. During the treatment period, OPC-21268 and ramipril reduced systolic blood pressure compared with control SHR (P < .001). Blood pressure in male SHR 7 weeks after treatment withdrawal was 178 +/- 1 mm Hg in ramipril-treated, 184 +/- 1 mm Hg in OPC-21268-treated, and 200 +/- 2 mm Hg in control SHR (P < .001). Similar results were seen in female SHR, although both OPC-21268 and ramipril were less effective antihypertensive agents in female compared with male SHR. The sustained attenuation in blood pressure was not associated with significant cardiovascular structural changes (left ventricular-to-body weight ratio, renal weight-to-body weight ratio, mesenteric resistance artery media-to-lumen ratio). Results of vasopressin V1A receptor binding kinetics and plasma renin or aldosterone concentrations did not suggest a lasting effect of OPC-21268 on the vasopressin system or of ramipril on the renin-angiotensin system following treatment withdrawal.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Antagonistas dos Receptores de Hormônios Antidiuréticos , Hipertensão/prevenção & controle , Piperidinas/uso terapêutico , Quinolonas/uso terapêutico , Ramipril/uso terapêutico , Envelhecimento , Animais , Pressão Sanguínea , Peso Corporal , Feminino , Hipertensão/genética , Hipertensão/fisiopatologia , Masculino , Ratos , Ratos Endogâmicos SHR
17.
J Mol Endocrinol ; 15(2): 105-15, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8800636

RESUMO

The insulin-like growth factors (IGF-I and IGF-II), their receptors and binding proteins (IGFBPs) are endogenously expressed in a number of tissues including the lung during fetal and neonatal development. This endogenous autocrine/paracrine IGF 'system', together with endocrine sources, contributes to the regulation of lung cell proliferation. We investigated the expression of the mRNAs encoding IGF-I, IGF-II, the type 1 IGF receptor (IGF-T1R) and two IGF-binding proteins (IGFBP-2 and IGFBP-4) in rat lung during the perinatum. These were compared in lung with surfactant apoprotein A (Sp-A) mRNA levels. mRNA in extracts of fetal tissues collected between day 17 of gestation (17f) and day 9 after birth (9d) was estimated by Northern blot or RNase protection analysis. At day 20 of gestation IGF-I, IGF-T1R and IGFBP-4 mRNA levels were higher in lung than liver (all P < 0.01), whereas IGF-II and IGFBP-2 mRNA levels were higher in liver than lung (each P < 0.02). The expression of IGF-1, IGFBP-2 and IGFBP-4 in lung was high before birth (days 17-20f) but decreased to low levels at days 21f, 22f or at birth (1d) but increased in the neonatal lung. IGF-II expression in lung was high at 17f but decreased before birth and remained low after birth. The IGF-T1R was expressed at moderate levels before birth, decrease before birth but peaked at days 2-5 after birth. The decrease in expression of these growth regulators before birth expression of these growth regulators before birth was matched by an increased in Sp-A expression which was clearly seen at day 20f, peaked at 1d and then was clearly seen at day 20f, peaked at 1d and then was maintained at high levels after birth. Primary cell cultures of 18f lung epithelia express IGFBP-2 while fibroblasts from the same animals express only IGFBP-4. Cells grown from 22f lung tissue express IGFBP-2 and IGFBP-4 at lower levels, behaving in vitro as they do in vivo. The contrasting levels of expression of different components of the IGF system in the fetal lung and liver indicate organ-specific regulation. IGFBP-2 and IGFBP-4 expression in different cell types within lung but with similar temporal changes suggests cell-specific regulation, perhaps by a common agent. The patterns by a common agent. The patterns of expression of IGF-I, IGF-T1R, IGFBP-2 and IGFBP-4, but not IGF-II, in developing lung correspond to previously described phasic changes in lung cell proliferation rates. The nadir in expression of these four major components of the lung IGF system occurs in the saccular phase when the lung begins to differentiate, probably under the influence of certain endocrine agents.


Assuntos
Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/biossíntese , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/biossíntese , Fator de Crescimento Insulin-Like II/biossíntese , Fator de Crescimento Insulin-Like I/biossíntese , Pulmão/metabolismo , Receptor IGF Tipo 1/biossíntese , Envelhecimento , Animais , Animais Recém-Nascidos , DNA Complementar , Desenvolvimento Embrionário e Fetal , Feminino , Feto , Expressão Gênica , Idade Gestacional , Fígado/embriologia , Fígado/metabolismo , Pulmão/embriologia , Pulmão/crescimento & desenvolvimento , Sondas de Oligonucleotídeos , Gravidez , Proteolipídeos/biossíntese , Proteína A Associada a Surfactante Pulmonar , Proteínas Associadas a Surfactantes Pulmonares , Surfactantes Pulmonares/biossíntese , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Ratos
18.
Biochim Biophys Acta ; 1263(3): 266-70, 1995 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-7548217

RESUMO

The gene for the sheep arginine vasopressin type 1a (V1a) receptor subtype was cloned from a genomic library. The deduced amino acid sequence shows characteristics of a G-protein coupled receptor and high sequence identity to human and rat V1a receptor sequences (81% and 73%, respectively). Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed a tissue distribution consistent with a type V1a receptor. The genomic DNA (7.1 kb) contains a 1586 bp intron between the putative 6th and 7th transmembrane domains.


Assuntos
Receptores de Vasopressinas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA/química , Biblioteca Genômica , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Ovinos
19.
J Am Diet Assoc ; 95(7): 769-74, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7797807

RESUMO

OBJECTIVE: To compare the effect of vegetable, fruit, and legume consumption on urinary isoflavonoid phytoestrogen and lignan excretion. DESIGN: After 4 days of data collection, during which subjects consumed their habitual diets, subjects were randomly placed on four 9-day controlled experimental diets with each subject receiving each diet in a random order. SUBJECTS: Seven men and three women, aged 20 to 35 years, were recruited from the University of Minnesota Twin Cities community. INTERVENTIONS: All subjects consumed four experimental diets in an assigned random order: a controlled basal diet, a legume/allium diet (containing garbanzo beans, garlic, and onions), and diets low or high in vegetables and fruits (containing apples, pears, potatoes, and carrots). MAIN OUTCOME MEASURES: Urine samples that were collected while subjects consumed their habitual diets and during the last 3 days of each feeding period were analyzed for isoflavonoid and lignan content using isotope dilution gas chromatography-mass spectrometry. STATISTICAL ANALYSIS PERFORMED: The effect of vegetable and fruit intake on urinary isoflavonoid and lignan excretion was analyzed using the general linear model procedure. Post hoc comparisons were made using Duncan's multiple range test. RESULTS: Subjects excreted more of the lignan enterodiol on the high vegetable/fruit diet compared with the basal and legume/allium diets (P = .03); more of the isoflavonoids O-desmethylangolensin (O-DMA), genistein, and sum of isoflavonoids on the legume/allium diet compared with the other controlled diets (P < .05); and more of the isoflavan equol on the basal and legume/allium diets compared with the high vegetable/fruit diet (P < .01). Subjects who excreted higher levels of equol on the basal and legume/allium diets also consumed more of the milk-based pudding provided as part of the controlled diets. CONCLUSIONS: Urinary lignan and isoflavonoid excretion changed in response to alterations in vegetable, fruit, and legume intake under controlled dietary conditions.


Assuntos
Estrogênios não Esteroides/urina , Fabaceae , Frutas , Lignanas/urina , Plantas Medicinais , Verduras , Adulto , Cromanos/urina , Estudos Cross-Over , Dieta , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Fibras na Dieta/administração & dosagem , Ingestão de Energia , Equol , Feminino , Flavonoides/urina , Genisteína , Humanos , Isoflavonas/urina , Masculino , Fitoestrógenos , Preparações de Plantas
20.
Clin Sci (Lond) ; 88(6): 671-4, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7634750

RESUMO

1. To investigate the mechanism of hepatic V1a vasopressin receptor down-regulation in streptozotocin-induced diabetes mellitus in the rat, we measured hepatic V1a receptor mRNA by in situ hybridization histochemistry using oligonucleotide probes to the V1a receptor and Northern blotting. 2. Diabetes mellitus caused hyperglycaemia, hyperosmolality and increased plasma vasopressin concentrations (P < 0.01). Hepatocyte V1a receptor mRNA was reduced by 76% in diabetic rats (P < 0.01) and by 53% in insulin-treated diabetic rats (P < 0.01) versus control rats, in parallel with reduced V1a radioligand binding and vasopressin-stimulated inositol phosphates production. There was a similar decrease in hepatic V1a/18S mRNA density ratio in the diabetic and diabetic+insulin groups (both P < 0.05 versus control). 3. These findings suggest that altered V1a mRNA transcription is responsible for the reduced hepatic V1a receptor density in diabetes mellitus.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Fígado/metabolismo , RNA Mensageiro/metabolismo , Receptores de Vasopressinas/metabolismo , Animais , Northern Blotting , Diabetes Mellitus Experimental/tratamento farmacológico , Feminino , Regulação da Expressão Gênica , Hibridização In Situ , Insulina/uso terapêutico , Ratos , Ratos Sprague-Dawley , Estreptozocina
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