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1.
Lett Appl Microbiol ; 73(3): 300-307, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34042204

RESUMO

Miscanthus sinensis growing in our study mine site contained a high concentration of Al in the adventitious roots. It has a root endophyte, Phialocephala fortinii, in its adventitious roots at a high frequency. The purpose of this study was to elucidate the effects of P. fortinii on Al tolerance mechanisms of M. sinensis and reveal potential underlying mechanisms. In the absence of P. fortinii, M. sinensis produced chlorogenic, citric, and malic acids that could act to alleviate Al toxicity in acidic mine soil. Up on fungal inoculation, the levels of these compounds were reduced, although the growth of seedlings and Mg concentration in the roots were increased. IAA production by the fungus may contribute to enhanced plant growth whereas an increase of Mg uptake could reduce toxicity of reactive oxygen species under Al stress. These actions of P. fortinii could promote growth and survival of M. sinensis in mine sites.


Assuntos
Alumínio , Solo , Alumínio/toxicidade , Ascomicetos , Raízes de Plantas , Poaceae
2.
Phys Chem Chem Phys ; 21(13): 7183-7195, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30888381

RESUMO

Cathode materials with highly reactive surfaces and long-term stability are required to achieve high-performance solid oxide fuel cells (SOFCs). In this study, a promising cathode material, La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF), was prepared as a nanostructured thin film using pulsed laser deposition (PLD) on gadolinia-doped ceria (GDC)-buffered YSZ single crystal substrates having (100) and (111) orientations. Characterization revealed intrinsic differences among the as-grown LSCF thin films in terms of dominant crystalline orientation and nanostructure depending on GDC preparation as well as the YSZ substrate orientation. Evaluation of the oxygen exchange properties using the isotope exchange depth profile method revealed that LSCF thin films grown on (111) GDC/YSZ exhibited higher values of the apparent surface exchange coefficient compared to LSCF thin films grown on (100) GDC/YSZ. However, when subjected to long-term annealing at high temperatures, the former exhibited a stronger tendency to surface segregation as compared to the latter. These behaviors are correlated with the intrinsic properties of LSCF thin films, including the nanostructure, the possible effects attributed to SrO activity, and the stability of perovskite surfaces which would drive surface segregation. These results have implications for tailoring the performance of cathode thin films by understanding the dependence of oxygen exchange properties and surface segregation on driving forces such as surface chemistry and nanostructure.

3.
J Dairy Sci ; 101(6): 4830-4841, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29573807

RESUMO

In a preliminary open-label trial by our group, Bifidobacterium bifidum YIT 10347 (YIT10347) relieved gastric symptoms in patients with functional gastrointestinal disorders. Hence, in this study, we investigated the effects of YIT10347 on gastrointestinal symptoms in healthy adults. In this prospective double-blind, randomized, placebo-controlled trial (UMIN000024654), 100 healthy Japanese adults were randomly assigned to a YIT10347 group or placebo group and consumed 100 mL of YIT10347-fermented milk or placebo fermented milk, respectively, every day for 4 wk. Gastrointestinal symptoms were evaluated by using the modified Frequency Scale for Symptoms of Gastroesophageal Reflux Disease (m-FSSG) and Gastrointestinal Symptom Rating Scale (GSRS) as primary endpoints. Mental symptoms, quality of life, salivary stress markers, and gastric emptying were evaluated as secondary endpoints. Effectiveness and safety were analyzed in a per-protocol set (YIT10347 group, n = 39; placebo group, n = 40) and full analysis set (YIT10347 group, n = 50; placebo group, n = 50), respectively. In the m-FSSG evaluation, the YIT10347 group had a significantly higher relief rate of postprandial discomfort and greater changes in postprandial epigastric pain score from baseline than the placebo group. In the GSRS evaluation, the YIT10347 group had significantly higher relief rates of overall gastrointestinal symptoms, upper gastrointestinal symptoms, flatus, and diarrhea than the placebo group. We detected no significant differences in scores or relief rates of mental symptoms and quality of life, a salivary stress marker, or gastric emptying between the 2 groups. No severe adverse events associated with test beverage consumption were observed in either group. These findings suggest that daily consumption of YIT10347-fermented milk exerts beneficial effects on gastrointestinal discomfort and symptoms such as postprandial discomfort and epigastric pain in healthy adults.


Assuntos
Bifidobacterium bifidum/metabolismo , Produtos Fermentados do Leite/microbiologia , Gastroenteropatias/tratamento farmacológico , Probióticos/administração & dosagem , Adulto , Animais , Produtos Fermentados do Leite/análise , Método Duplo-Cego , Feminino , Fermentação , Esvaziamento Gástrico/efeitos dos fármacos , Gastroenteropatias/dietoterapia , Gastroenteropatias/fisiopatologia , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Leite/metabolismo , Leite/microbiologia , Estudos Prospectivos , Qualidade de Vida , Adulto Jovem
4.
Allergy ; 71(3): 421-5, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26551325

RESUMO

Recent studies revealed that Amblyomma or Ixodes tick bites may cause red meat allergy, in which galactose-α-1,3-galactose (α-Gal) is a major IgE-binding epitope. The incidence of red meat allergy is high in Shimane Prefecture, as is tick-transmitted Japanese spotted fever. Therefore, we speculated that tick bites may cause these meat allergies. The carbohydrate α-Gal was detected in the salivary gland protein of Haemaphysalis longicornis (H. longicornis), the vector for Japanese spotted fever, by immunoblotting using anti-α-Gal antibody. H. longicornis salivary gland protein-specific IgE was detected in the sera of 24 of 30 patients with red meat allergies. Sensitization to tick salivary gland protein containing α-Gal is possibly a major etiology of red meat allergy; the carbohydrate plays a crucial role in its allergenicity. These results further indicate that the α-Gal epitope is present not only in Amblyomma or Ixodes, but also in Haemaphysalis.


Assuntos
Alérgenos/imunologia , Hipersensibilidade Alimentar/epidemiologia , Hipersensibilidade Alimentar/etiologia , Ixodes , Carne Vermelha/efeitos adversos , Picadas de Carrapatos , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Hipersensibilidade Alimentar/diagnóstico , Galactose/imunologia , Geografia , Humanos , Imunoglobulina E/imunologia , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade
5.
Parasitology ; 139(12): 1553-61, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22906745

RESUMO

Eimeria tenella is recognized worldwide as a significant pathogen in the poultry industry. However, a lack of methods for isolating developing schizonts has hindered the use of transcriptome analyses to discover novel and developmentally regulated genes. In the present study, we characterized the long-term successive development of E. tenella in infected chicken caeca and assessed the utility of laser microdissection (LMD) for the isolation of schizont RNA. Developmental stages, including those of the first, second, and third-generation schizonts and gametocytes, were synchronous. Using LMD, only the mature second-generation schizonts were successfully excised from the lamina propria, and non-degraded RNA was purified from the schizonts. E. tenella-specific genes were amplified by reverse transcription polymerase chain reaction (RT-PCR). These results augment our understanding of the E. tenella life cycle, and reveal LMD as a potentially useful tool for gene expression analyses of the intracellular stages of E. tenella.


Assuntos
Ceco/parasitologia , Eimeria tenella/fisiologia , Microdissecção , RNA de Protozoário/isolamento & purificação , Esquizontes/fisiologia , Animais , Galinhas , Eimeria tenella/genética , Estágios do Ciclo de Vida
6.
Diabetologia ; 53(7): 1362-71, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20390404

RESUMO

AIMS/HYPOTHESIS: Diabetogenic loci for type 2 diabetes have been mapped to mouse chromosome (Chr) 11 and 14 in the Nagoya-Shibata-Yasuda (NSY) mouse, an animal model of type 2 diabetes. We aimed to obtain direct evidence of these genes on each chromosome and to clarify their function and interaction in conferring susceptibility to type 2 diabetes. METHODS: We established three consomic strains homozygous for diabetogenic NSY-Chr11, NSY-Chr14 or both on the control C3H background (C3H-11(NSY), C3H-14(NSY) and C3H-11(NSY)14(NSY), respectively), and monitored diabetes-related phenotypes longitudinally. The glucokinase gene was sequenced as a positional candidate gene on Chr11. RESULTS: C3H-11(NSY) mice showed hyperglycaemia associated with impaired insulin secretion and age-dependent insulin resistance without obesity. C3H-14(NSY) mice exhibited hyperglycaemia mainly due to insulin resistance, with a slight increase in percentage body fat. C3H-11(NSY)14(NSY) double consomic mice showed marked hyperglycaemia and obesity, which was not observed in single consomic strains. Sequences of the glucokinase gene were allelically variant between NSY and C3H mice. CONCLUSIONS/INTERPRETATION: These data provide direct evidence that Chr11 and Chr14 harbour major susceptibility genes for type 2 diabetes. These two chromosomes interact to cause more severe hyperglycaemia and obesity, which was not observed with the presence of either single chromosome, indicating different modes of gene-gene interaction depending on the phenotype. Marked changes in the phenotypes retained in the consomic strains will facilitate fine mapping and the identification of the responsible genes and their interaction with each other, other genes and environmental factors.


Assuntos
Cromossomos de Mamíferos/genética , Diabetes Mellitus Tipo 2/genética , Animais , Predisposição Genética para Doença/genética , Hiperglicemia/genética , Camundongos , Fenótipo
7.
Radiat Prot Dosimetry ; 184(3-4): 385-387, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31038705

RESUMO

Some microorganisms in the environment make siderophores, which are low molecular chelators, to take up minerals from soil. Eleven bacteria were separated from the root of white clover by chlome azrol S (CAS) assay. Each bacterium was incubated in casamino acid (CAA) culture, and siderophores in CAA culture were purified. These extractions were applied to biotite or vermiculite spiked with Cs. From each clay mineral, 57.1-72.8% (5100 ppm), 55.6-63.8% (920 ppm) and 48.6-54.3% (2300 ppm), 31.6-34.4% (520 ppm) was eluted, respectively. To understand elution behaviour, Cs desorption ratio of each clay was measured every 30 min. The results indicate Cs elution was occurred quickly.


Assuntos
Bactérias/metabolismo , Radioisótopos de Césio/análise , Argila/química , Minerais/análise , Microbiologia do Solo , Poluentes Radioativos do Solo/análise , Silicatos de Alumínio/química , Argila/microbiologia , Compostos Ferrosos/química , Medicago/microbiologia , Raízes de Plantas/microbiologia , Sideróforos/metabolismo
8.
J Clin Invest ; 101(9): 1951-9, 1998 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-9576760

RESUMO

Lupus anticoagulant (LAC) is associated with arterial and venous thrombosis, thrombocytopenia, and recurrent fetal loss. We have reported previously that plasma with LAC activity induces apoptosis in endothelial cells and binds annexin V (Nakamura, N., Y. Shidara, N. Kawaguchi, C. Azuma, N. Mitsuda, S. Onishi, K. Yamaji, and Y. Wada. 1994. Biochem. Biophys. Res. Commun. 205:1488-1493). In this study, we separated two IgG antibody fractions, one with and one without affinity for annexin V, from 10 patients with LAC. LAC and apoptotic activities were localized in the annexin V-binding fraction in all 10 patients. DNA fragmentation was dose-dependent, paralleling the amount of IgG added to the human umbilical vein endothelial cell culture medium, and was inhibited by preincubation with annexin V. Removal of the antiphospholipid antibodies from patient IgG with phospholipid liposomes did not abolish the apoptosis-inducing activities or binding to annexin V. These results imply that patients with LAC often have antibodies that do not bind phospholipids and are responsible for the induction of apoptosis in endothelial cells.


Assuntos
Anexina A5/imunologia , Apoptose/imunologia , Endotélio Vascular/efeitos dos fármacos , Inibidor de Coagulação do Lúpus/farmacologia , Lúpus Eritematoso Sistêmico/imunologia , Adulto , Endotélio Vascular/citologia , Feminino , Glicoproteínas/farmacologia , Humanos , Imunoglobulina G/farmacologia , Testes de Neutralização , beta 2-Glicoproteína I
9.
Clin Nephrol ; 68(6): 401-4, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18184523

RESUMO

UNLABELLED: Although dietary control is recommended to chronic kidney disease (CKD) patients, improvement of compliance and education of outpatients are very difficult. The purposes of the present study are to estimate the dietary intake of sodium (Na) and protein by measuring urinary Na and urea nitrogen (UN) excretion, and to evaluate the efficacy of educational hospitalization. METHODS: 70 patients (41 men and 29 women) with a mean age of 58.7+/-15.8 years participated in the present study. Most patients had chronic kidney disease (CKD, Stage 3 or 4). Patients were hospitalized to learn about their diseases and dietary restrictions for 1 week. Patients were given low salt (less than 6 g/day) and low protein (0.6-1.0 g/standard body weight kg/day) diet. 24-hour urine samples were collected at the start (Day 2) and on completion (Day 7) of hospitalization. Salt and protein intakes were estimated using patients' 24-hour urine samples. RESULTS: Estimated salt intake was significantly decreased on completion of the hospitalization (Day 7) (p < 0.05). Estimated protein intake was also decreased slightly, but this was not statistically significant. There were significant differences in the changes of body weight, body mass index (BMI), and systolic and diastolic blood pressure between the start (Day 2) and completion (Day 7) of hospitalization. 89% of the patients showed an improved blood pressure without changes of antihypertensive drugs. CONCLUSIONS: It appears that short-term hospitalization is an effective program for achieving dietary and blood pressure control in CKD patients.


Assuntos
Proteínas Alimentares , Hospitalização , Nefropatias/terapia , Educação de Pacientes como Assunto , Sódio na Dieta , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Alimentares/administração & dosagem , Feminino , Humanos , Nefropatias/urina , Masculino , Pessoa de Meia-Idade , Sódio na Dieta/administração & dosagem
10.
Cancer Res ; 55(7): 1586-9, 1995 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-7882369

RESUMO

We have reported previously that a factor with a molecular weight of 53,000 under SDS-polyacrylamide gel electrophoresis purified from human erythrocyte extracts promoted the growth of a wide variety of cell types from different species, including T cells, B cells, myeloid leukemia cells, melanoma cells, and mastocytoma cells, as well as normal and transformed fibroblast cells. In the present study, amino acid sequence analysis revealed that this factor has homology with human catalase. The purified factor exhibited catalase activity. Catalases derived from human erythrocytes, bovine liver, Aspergillus niger, and recombinant rat liver catalase are all able to promote the growth of cells. Antibody against human catalase absorbed both the growth-promoting activity and the enzyme activity of the purified factor. In addition, treatment of the factor with an irreversible enzyme inhibitor, aminotriazole, resulted in abrogation of both the growth-promoting activity and enzyme activity. These results indicate that the growth-promoting factor is catalase, and its activity is associated with the decomposition of hydrogen peroxide.


Assuntos
Catalase/isolamento & purificação , Eritrócitos/enzimologia , Substâncias de Crescimento/isolamento & purificação , Sequência de Aminoácidos , Catalase/química , Substâncias de Crescimento/química , Humanos , Dados de Sequência Molecular , Peso Molecular , Células Tumorais Cultivadas
12.
Arch Intern Med ; 158(2): 177-81, 1998 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-9448556

RESUMO

BACKGROUND: Interferon alfa is used widely for patients with chronic hepatitis C virus (HCV) infection. Little is known, however, of the relationship between patients' sex and the effectiveness of interferon alfa treatment in these patients. METHODS: We treated 311 patients (199 men and 112 women) with human lymphoblastoid interferon (6 million units subcutaneously every day for 2 weeks and 3 times a week for 22 weeks) and observed them for an additional 6 months. Serum HCV RNA levels and genotype were tested by polymerase chain reaction before treatment. A liver biopsy was also done. For the purposes of this study, a complete response was defined as the elimination of HCV RNA for at least 6 months after the termination of treatment. RESULTS: The rate of complete response was 27.1% for men and 24.1% for women. With multiple logistic regression analysis, the HCV RNA level (P < .001), genotype (P < .001), patients' sex (P < .05), and the interaction between sex and age were associated with a complete response to interferon alfa. The rate of complete response was 33.3% in men aged 39 years and younger, 25.0% in men aged 40 years and older. 75.0% in women aged 39 years and younger, and 15.6% in women aged 40 years and older. The odds ratio by group was 1.00, 0.72, 4.38, and 0.21, respectively. CONCLUSIONS: Our finding that women aged 39 years and younger are responsive to interferon alfa treatment suggests that hormonal activity, in particular the level of estrogen, may be associated with the sustained elimination of HCV.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adulto , Fatores Etários , Feminino , Hepacivirus/genética , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , RNA Viral/análise , Fatores Sexuais , Resultado do Tratamento
13.
J Anim Sci ; 93(6): 2778-84, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26115265

RESUMO

The hyperinsulinemic-euglycemic clamp (EGC) technique was used to investigate the effects of calcium salts of long-chain fatty acids (LCFA-Ca) and rumen-protected Met (RPM) on insulin sensitivity in the peripheral tissues of lactating cows. Six multiparous Holstein cows were used in a 3 × 3 Latin square experiment in each 14-d period. Dietary treatments were 0 (RPM0), 20 (RPM20), and 60 (RPM60) g/d of RPM, supplemented with a diet containing 1.5% of LCFA-Ca equal to 110% of the cows' ME requirement. And as a control for the 3 LCFA-Ca-containing diets, a dietary treatment without LCFA-Ca (Con) was also included. After a 10-d adaptation period, milk samples were collected for 4 d, and EGC experiments were performed on d 14 of each treatment period. Insulin solution was infused through a jugular vein catheter at a rate of 0.1, 0.2, 0.3, and 0.4 milliunits·kg BW-1·min-1 for 30 min and then at a rate of 0.5 milliunits·kg BW-1·min-1 for 60 min. Glucose solution was variably infused to maintain plasma glucose at steady state through the same catheter. Blood samples for measurements were taken using the contralateral catheter. Plasma total cholesterol, cholesterol ester, free cholesterol, and phospholipid concentrations in RPM0 and RPM20 were higher than those in Con, whereas the concentrations in RPM60 were low at the same degree of those in RPM0 (P < 0.05). Plasma Met concentration was greatest in RPM60 (P < 0.05). In the EGC experiment, the glucose infusion rate was greater in RPM60 than in RPM0 and RPM20 and an effective concentration of insulin resulting in 50% maximal glucose infusion rate was lower in RPM60 compared with RPM0 (P < 0.05), indicating that insulin sensitivity was intensified in RPM60. Although the insulin sensitivity evaluated from the EGC data in RPM0, RPM20, and RPM60 was not different from Con, a slight decline was observed in RPM0 and insulin sensitivity in RPM60 was higher than Con. Our results from the EGC experiment demonstrated that the feeding RPM lead to increased insulin sensitivity, which suggests that dietary Met affects lipid metabolism via insulin action in lactating dairy cows fed a LCFA-Ca-containing diet.


Assuntos
Dieta Hiperlipídica/veterinária , Gorduras na Dieta/farmacologia , Resistência à Insulina/fisiologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metionina/farmacologia , Animais , Bovinos , Colesterol/sangue , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Ácidos Graxos/metabolismo , Feminino , Glucose/administração & dosagem , Insulina/administração & dosagem , Insulina/sangue , Lactação/fisiologia , Metionina/sangue , Leite/metabolismo , Rúmen/metabolismo
14.
J Immunol Methods ; 279(1-2): 135-42, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12969554

RESUMO

BACKGROUND: We have shown that measurement of mRNA for cytotoxic attack proteins perforin and granzyme B in urinary cells is a noninvasive means of diagnosing acute rejection of human renal allografts. Urinary cell mRNA studies have yielded useful information in other patient populations such as patients with cancer. The isolation of sufficient and high quality ribonucleic acid (RNA) from urinary cells however is problematic. RNAlater, an RNA stabilization solution, has been reported to optimize RNA isolation from tumor tissues stored at room temperature and from pigment-rich ocular tissues. METHODS: We explored whether the addition of RNAlater to urine cell pellets improves RNA yield, enhances purity and facilitates measurement of low abundance mRNAs. We measured, with the use of real-time quantitative polymerase chain reaction (PCR) assay, levels of expression of a constitutively expressed gene 18S rRNA and mRNA for granzyme B and transforming growth factor-beta(1) (TGF-beta(1)) in urine specimens and renal biopsies obtained from renal allograft recipients. RESULTS: RNA yield (P<0.01, Wilcoxon signed rank test) and the A260/A280 ratio (P<0.01) were both higher with urine cell pellets treated with RNAlater prior to snap freezing compared to cell pellets that were not treated with RNAlater prior to snap freezing. Levels (copy number per 1 microg of total RNA) of 18S rRNA (P<0.02), granzyme B mRNA (P=0.002) and TGF-beta(1) (P=0.02) were all higher with treated urine cell pellets compared to untreated cell pellets. Kruskall-Wallis one way analysis of variance and pair-wise comparisons with Student-Newman-Keuls test showed that the levels of mRNA for granzyme B (P<0.05) and TGF-beta(1) (P<0.05) are significantly different between renal allograft biopsies and untreated urine cell pellets but not between the biopsy specimens and RNAlater-treated urine cell pellets. CONCLUSIONS: The addition of RNAlater to urine cell pellets improves RNA isolation from urinary cells and facilitates measurement of low abundance mRNAs.


Assuntos
RNA/isolamento & purificação , Urina/citologia , Adolescente , Criança , Granzimas , Humanos , RNA/análise , RNA/urina , RNA Ribossômico 18S/urina , Serina Endopeptidases/genética , Espectrofotometria , Fator de Crescimento Transformador beta/genética
15.
J Med Chem ; 38(12): 2176-87, 1995 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-7783149

RESUMO

Agelasphin-9b, (2S,3S,4R)-1-O-(alpha-D-galactopyranosyl)-16-methyl-2- [N-((R)-2- hydroxytetracosanoyl)-amino]- 1,3,4-heptadecanetriol, is a potent antitumor agent isolated from the marine sponge Agelas mauritianus. Various analogues of agelasphin-9b (a lead compound) were synthesized, and the relationship between their structures and biological activities was examined using several assay systems. From the results, KRN7000, (2S,3S,4R)-1-O-(alpha-D- galactopyranosyl)-2-(N-hexacosanoylamino)-1,3,4-octadecanetriol , was selected as a candidate for clinical application.


Assuntos
Antineoplásicos/farmacologia , Galactosilceramidas/farmacologia , Melanoma Experimental/patologia , Animais , Antineoplásicos/química , Divisão Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Sangue Fetal , Galactosilceramidas/química , Humanos , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Poríferos/química , Baço/citologia , Baço/efeitos dos fármacos , Relação Estrutura-Atividade
16.
J Endocrinol ; 129(2): 301-7, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2040863

RESUMO

Maternal plasma concentrations of immunoreactive endothelin (ir-ET) during pregnancy, labour and after birth were measured by radioimmunoassay. Concentrations of ir-ET in the umbilical artery, umbilical vein, amniotic fluid and neonatal urine were also examined. The mean (+/- S.E.M.) plasma ir-ET concentration in early pregnancy (4-7 weeks) was 13.7 +/- 0.5 pmol/l, which was significantly higher than that in non-pregnant women (5.9 +/- 0.3 pmol/l). During pregnancy, plasma ir-ET concentrations gradually decreased to a minimum of 11.5 +/- 0.4 pmol/l in weeks 20-23, and then increased again towards term (12.5 +/- 0.4 pmol/l after 36 weeks of pregnancy). In women undergoing vaginal delivery, the mean plasma ir-ET concentration (17.1 +/- 0.7 pmol/l) increased significantly, compared with that in late pregnancy. After delivery, the plasma ir-ET concentration decreased abruptly to 4.0 +/- 0.2 pmol/l on the first day. Plasma ir-ET concentrations in umbilical vessels were significantly higher than those in maternal plasma. In addition, concentrations in the umbilical artery were significantly higher than those in the umbilical vein in cases of vaginal delivery. Concentrations of ir-ET in amniotic fluid were much higher than those in maternal or fetal plasma. ir-ET concentrations in neonatal urine on day 1 after birth were below the detection limit (less than 0.1 pmol/l) by radioimmunoassay in 70% of the cases examined but on day 5 after birth ir-ET was present at measurable concentrations in all cases. It is suggested that endothelin may act as a circulating hormone during pregnancy and labour in both maternal and fetal circulations.


Assuntos
Endotelinas/sangue , Gravidez/sangue , Líquido Amniótico/metabolismo , Cesárea , Endotelinas/imunologia , Feminino , Humanos , Recém-Nascido/sangue , Trabalho de Parto/sangue , Radioimunoensaio , Artérias Umbilicais/química , Veias Umbilicais/química
17.
AIDS Res Hum Retroviruses ; 17(16): 1507-15, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11709095

RESUMO

HIV-1 infection results in a gradual decrease in CD4(+) T cell counts and progressive immune deficiency. Increased T cell turnover in HIV-1-infected patients, which can be interpreted as T cell clonal expansion, has been thought to be relevant to its pathogenesis. To investigate whether B cell clonal expansion also occurs in HIV-1-infected patients, we examined the expressed V(H)DJ(H) gene sequences of peripheral B cells in HIV-1-infected patients with hypergammaglobulinemia. Identical V(H)DJ(H) gene rearrangements with additional nucleotide differences in V(H) genes were analyzed as a marker of clonally related B cells. From healthy individuals and HIV-1-uninfected patients with hypergammaglobulinemia, clonally related B cells were detected in none of 10 (0%) and 2 of 10 (20%), respectively. No clonally related B cells were detected in any of the nine HIV-1-infected patients with detectable viral loads and normal Ig levels (0%). In contrast, from 9 of 14 HIV-1-infected patients with hypergammaglobulinemia (64%), clonally related B cells were detected. In addition, no HIV-1-infected patients who exhibited normal Ig levels after antiretroviral therapy had clonally related B cells. These findings suggest that B cell clonal expansion is present in HIV-1-infected patients with hypergammaglobulinemia.


Assuntos
Linfócitos B/imunologia , Infecções por HIV/complicações , HIV-1/imunologia , Hipergamaglobulinemia/imunologia , Ativação Linfocitária/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fármacos Anti-HIV/uso terapêutico , Sequência de Bases , Feminino , Rearranjo Gênico do Linfócito B/genética , Genes de Imunoglobulinas/genética , Infecções por HIV/tratamento farmacológico , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA
18.
Antiviral Res ; 32(1): 9-18, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8863991

RESUMO

The hepatitis C virus (HCV) genome contains the code for a conserved, serine-type protease, called NS3, for the processing of the non-structural protein region of the viral polyproteins. Furthermore, a related protein, NS4A, is an effector or cofactor of NS3 protease activity in the cleavage of NS3-4A, NS4A-4B, NS4B-5A and NS5A-5B junctions. To establish an in vitro assay system for the screening of those enzyme inhibitors that inhibit the protease NS3-4A, we prepared a maltose-binding protein-NS3-NS4A fusion protein and a synthetic peptide substrate that mimics the NS5A-5B junction. Cleavage of the synthetic peptide was analyzed by reversed-phase high performance liquid chromatography (HPLC). We showed that the enzymatic activity of the NS3-NS4A fusion protein was enhanced in comparison to the NS3 protein alone. The assay conditions for optimum NS3-4A protease activity were determined to be pH 7.6 and 37 degrees C. In addition, we evaluated several protease inhibitors using the same HPLC assay system. The activity of HCV protease NS3-4A was inhibited by 2714.4 microM diisopropyl fluorophosphate, 270.8 microM N-tosyl-L-lysyl chloromethyl ketone, and 825.5 microM chymostatin. The results of the present study indicated that the synthetic peptide substrate and HPLC assay system are suitable for studying HCV protease activity and may facilitate the development of anti-HCV therapeutic reagents.


Assuntos
Antivirais/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Hepacivirus/efeitos dos fármacos , Hepacivirus/enzimologia , Inibidores de Serina Proteinase/farmacologia , Sequência de Aminoácidos , Sequência de Bases , Proteínas de Transporte/genética , Primers do DNA/genética , DNA Viral/genética , Hepacivirus/genética , Técnicas In Vitro , Proteínas Ligantes de Maltose , Dados de Sequência Molecular , Peptídeos/genética , Proteínas Recombinantes de Fusão/antagonistas & inibidores , Proteínas Recombinantes de Fusão/genética , Serina Endopeptidases/genética , Especificidade por Substrato , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/genética
19.
Cardiovasc Pathol ; 10(6): 297-303, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11755375

RESUMO

The majority of left ventricular (LV) inflow volumes in hypertrophic cardiomyopathy (HCM) depend on atrial contraction because of impaired LV relaxation. If HCM is complicated by atrial fibrillation (AF), heart failure can develop because of the loss of atrial contraction. The purpose of this study was to determine the relationship between the development of AF and myocardial fibrosis or intramyocardial small artery (IMSA) stenosis in autopsied hearts with HCM. Studies were performed in five HCM hearts with AF (AF group) and five HCM hearts without AF (non-AF group). LV specimens were divided into the inner (IT), middle (MT), and outer (OT) thirds. We selected at random 120 fields and 20 IMSAs from each layer and assessed them quantitatively using an image analyzer. We determined the extent of fibrosis (%F) and the degree of stenosis of each IMSA (%L). The %F in the AF group was greater than in the non-AF group (P<.01). In the AF group, the %F of the IT was greater than in the MT and the OT (P<.01). In the non-AF group, the %F of the IT was greater than in the MT (P<.05), and the %F of the MT was greater than in the OT (P<.01). The %L was similar in the AF and non-AF groups. In both groups, the %L of the IT was lower than in the MT (P<.01), which was lower than that of the OT (P<.05). LV fibrosis is more severe in patients with HCM and AF than in those without AF. Therefore, myocardial fibrosis might impair LV relaxation, resulting in hemodynamic intolerance to AF.


Assuntos
Fibrilação Atrial/etiologia , Cardiomiopatia Hipertrófica/complicações , Miocárdio/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/patologia , Estenose Coronária/complicações , Estenose Coronária/patologia , Progressão da Doença , Feminino , Fibrose , Ventrículos do Coração/patologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade
20.
Ann N Y Acad Sci ; 902: 315-9, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10865855

RESUMO

We demonstrated that leptin showed effects on both platelets and endothelial cells through its functional receptor. These effects are the vector to inducing thrombotic tendency. Leptin concentrations used in our experiments correspond to that of leptin in the circulation of obese individuals. Thus we suggest that increased leptin may act as a risk factor for thrombosis in obese individuals.


Assuntos
Arteriosclerose/fisiopatologia , Plaquetas/fisiologia , Endotélio Vascular/fisiologia , Leptina/farmacologia , Obesidade/fisiopatologia , Receptores de Superfície Celular , Difosfato de Adenosina/farmacologia , Arteriosclerose/sangue , Plaquetas/efeitos dos fármacos , Proteínas Sanguíneas/metabolismo , Proteínas de Transporte/sangue , Proteínas de Transporte/fisiologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Obesidade/sangue , Fosforilação , Agregação Plaquetária/efeitos dos fármacos , Receptores para Leptina , Trombomodulina/metabolismo
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