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1.
Clin Exp Immunol ; 193(3): 327-340, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29745428

RESUMO

Ovarian cancers are known to evade immunosurveillance and to orchestrate a suppressive immune microenvironment. Here we examine the role of human epididymis protein 4 (HE4), an ovarian cancer biomarker, in immune evasion. Through modified subtractive hybridization analyses we have characterized the gene targets of HE4 in human peripheral blood mononuclear cells (PBMCs), and established a preliminary mechanism for HE4-mediated immune failure in ovarian tumours. Upon exposure of purified PMBCs to HE4, osteopontin (OPN) and dual-specificity phosphatase 6 (DUSP6) emerged as the most suppressed and up-regulated genes, respectively. SKOV3 and OVCAR8, human ovarian carcinoma cell lines, exhibited enhanced proliferation in conditioned media from HE4-exposed PBMCs, an effect that was attenuated by the addition of recombinant OPN or OPN-inducible cytokines [interleukin (IL)-12 and interferon (IFN)-Ɣ]. Additionally, upon co-culture with PBMCs, HE4-silenced SKOV3 cells were found to be more susceptible to cytotoxic cell death. The relationship between HE4 and OPN was reinforced further through the analysis of serous ovarian cancer patient samples. In these biopsy specimens, the number of OPN+ T cells correlated positively with progression free survival (PFS) and inversely with serum HE4 level. Taken together, these findings show that HE4 enhances ovarian cancer tumorigenesis by compromising OPN-mediated T cell activation.


Assuntos
Fosfatase 6 de Especificidade Dupla/metabolismo , Leucócitos Mononucleares/fisiologia , Osteopontina/metabolismo , Neoplasias Ovarianas/imunologia , Proteínas/metabolismo , Linfócitos T/imunologia , Linhagem Celular Tumoral , Proliferação de Células , Citotoxicidade Imunológica , Fosfatase 6 de Especificidade Dupla/genética , Feminino , Regulação da Expressão Gênica , Humanos , Tolerância Imunológica , Interferon gama/metabolismo , Interleucina-12/metabolismo , Osteopontina/genética , Neoplasias Ovarianas/mortalidade , Proteínas/genética , RNA Interferente Pequeno/genética , Análise de Sobrevida , Evasão Tumoral , Microambiente Tumoral , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos
2.
Clin Chim Acta ; 365(1-2): 68-77, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16257399

RESUMO

In arthritic diseases e.g. osteoarthritis (OA) and rheumatoid arthritis (RA), the stability of the collagen type II (CII) fibers, a major component of articular cartilage, is compromised with extensive proteolytic breakdown leading to cartilage erosion and joint deterioration. A clinical need for molecular markers that give instantaneous measure of rate of joint deterioration has developed, as other measurements e.g. arthroscopy, and joint space narrowing are insensitive to small changes in disease status over short periods of time. Owing to its exclusive presence in cartilaginous tissues, markers of CII synthesis and degradation have been extensively studied. Assays that measure these markers in biological fluids e.g. synovial fluid (SF), serum, and urine have been developed and applied to detect early disease onset, monitor disease progression, and response to anti-arthritic drugs. CII synthesis markers include the procollagen type II C-propeptide (PIICP) and the procollagen type IIA N-propeptide (PIIANP). CII degradation markers include CII C-telopeptide (CII-X), CII neoepitope (TIINE), helix II, C2C, CNBr 9.7, Coll 2-1, and Coll 2-1 NO(2). Most of these markers differentiate between early stages of OA, RA and reference controls. The best correlations with structural changes occur when measurements are made in SF while serum measurement frequently did not correlate with structural changes. Although the selection of an optimal marker or a set of markers is still problematic, few markers are of considerable utility in early detection and monitoring of arthritic diseases. The current challenge is to improve the discriminatory power of these markers so they can be used to guide therapeutic decisions.


Assuntos
Artrite Reumatoide/metabolismo , Biomarcadores/metabolismo , Colágeno/metabolismo , Osteoartrite/metabolismo , Humanos , Hidrólise
3.
Am J Clin Nutr ; 31(1): 12-22, 1978 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-579565

RESUMO

The protein requirement and the efficiency of protein used were studied in young and old adult human subjects. Protein intake levels (N X 6.25) of 0.4, 0.8, and 1.6 g/kg body weight per day from a combination wheat-soy-milk mixture were fed. Caloric intake was held constant at 40 kcal/kg body weight per day throughout the 11-day study of each dietary period. No significant differences were observed in their protein requirement, efficiency of protein use or the ability to adapt to changes of protein intake levels. Protein digestibility was not impaired in the aged. It is concluded that the protein requirement and the efficiency of protein use are not affected by the aging process.


Assuntos
Proteínas Alimentares , Nitrogênio/metabolismo , Adaptação Fisiológica , Adulto , Idoso , Envelhecimento , Animais , Proteínas Alimentares/metabolismo , Proteínas Alimentares/normas , Ingestão de Energia , Humanos , Masculino , Pessoa de Meia-Idade , Leite , Necessidades Nutricionais , Glycine max , Triticum
4.
Am J Clin Nutr ; 32(10): 1989-93, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-114042

RESUMO

Low-lactose milk was produced by incubating cow's milk with yeast lactase. Sixteen lactose tolerant and 15 intolerant volunteers ingested 500 ml of the product twice daily for 1 month. During the testing period all subjects received on three occasions the same volume of unmodified milk in double-blind tests. Symptoms recorded throughout the study and for an additional 15 day base-line observation period were: diarrhea, abdominal pain and distention, flatulence, heartburn, and headache. Low-lactose milk acceptance was excellent. No significant differences were found between tolerants and intolerants during the base-line period and while ingesting low-lactose milk. By contrast, unmodified milk induced severe symptoms only in the intolerants. Availability of low-lactose milk and of its by-products allows consumption of greater volumes of this highly nutritious food by subjects with lactose intolerance with none or less symptoms compared to unmodified milk.


Assuntos
Intolerância à Lactose/metabolismo , Leite/metabolismo , Adolescente , Adulto , Animais , Método Duplo-Cego , Humanos , Lactose/análise , Intolerância à Lactose/complicações , Intolerância à Lactose/terapia , Masculino , Leite/efeitos adversos , Leite/análise , Leite/normas , beta-Galactosidase
5.
Am J Clin Nutr ; 49(2): 225-38, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2644802

RESUMO

Relative bioavailability of two iron fortificants, electrolytic Fe and ferric orthophosphate, was related to that of the reference ferrous sulfate with in vitro and rat model depletion-repletion methods in four laboratories to compare values directly with those obtained in a parallel human study. In vitro testing was performed on Fe compounds with both solubility and dialysis in a simulated in vitro gastrointestinal digestion system. Two depletion-repletion techniques, hemoglobin-regeneration efficiency (HRE) and an official method of the Association of Official Analytical Chemists (AOAC), were examined. AOAC relative biological values (RBV) of electrolytic Fe were 0.66 and 0.78 and of FePO4 were 0.25 and 0.34. HRE values were 0.78 and 0.58 for electrolytic Fe and FePO4, respectively. When compared with FeSO4 in a radiolabeled farina-based meal fed to humans, the RBV of FePO4 was 0.25 and electrolytic Fe 0.75. Results obtained with the AOAC method serve as the most reliable prediction of Fe bioavailability in the human although in vitro dialysis is a promising screening technique.


Assuntos
Ferro/farmacocinética , Animais , Disponibilidade Biológica
6.
Atherosclerosis ; 99(2): 195-206, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8503948

RESUMO

Doxazosin was administered to rabbits fed diets enriched in cholesterol and peanut oil for 7.5 or 12 weeks, in 2 separate experiments. Doxazosin suppressed the accumulation of cholesterol and formation of atherosclerotic plaques in the aortas of treated rabbits and prevented a diet-induced increase in aortic collagen and wall mass. Doxazosin was more effective in the thoracic and abdominal segments of the aorta than in the aortic arch. Pharmacokinetic analysis indicated that treated rabbits were exposed to concentrations of doxazosin, integrated over 24 h, which were consistent with the therapeutic range of doxazosin measured in patients treated for hypertension. Doxazosin did not alter serum levels of cholesterol or triglycerides, nor were there any consistent effects on glucose, free fatty acid or ketone levels. Hypotheses of the mechanism of action of doxazosin are discussed, including the possible involvement of alpha 1-adrenergic receptors in recruitment of smooth muscle cells by subintimal macrophages and nonadrenergic mechanisms of inhibition of lipid infiltration.


Assuntos
Arteriosclerose/metabolismo , Doxazossina/farmacologia , Animais , Aorta/metabolismo , Colesterol/metabolismo , Colesterol na Dieta/administração & dosagem , Colágeno/metabolismo , Doxazossina/farmacocinética , Elastina/metabolismo , Metabolismo dos Lipídeos , Masculino , Coelhos
7.
J Immunol Methods ; 159(1-2): 53-62, 1993 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-8445265

RESUMO

This paper describes the development of quantitative immunoassays utilizing mouse monoclonal antibodies which are monospecific to type II collagen. The monoclonal antibodies were characterized and tested extensively for reactivity against a panel of antigens including actin, myoglobin, thyroglobulin, ssDNA, tetanus toxin and different types of collagens including their CnBr-derived peptides. Four monoclonal antibodies having strict monospecificity to type II collagen were selected. Quantitative immunoassays developed with these antibodies can measure either type II collagen in its native conformation or type II collagen-derived cyanogen bromide peptides. The assay conditions such as coating concentration of antigen, monoclonal antibody concentration, second antibody concentration and incubation times were optimized to obtain maximum possible sensitivity. These quantitative immunoassays can be employed to measure type II collagen or type II collagen-derived peptides in low amounts ranging from 20 to 100 ng/ml. The assays can be applied to chondrocyte cultures without interference from serum components or other collagen types.


Assuntos
Colágeno/análise , Ensaio de Imunoadsorção Enzimática , Fragmentos de Peptídeos/análise , Animais , Anticorpos Monoclonais/imunologia , Condrossarcoma/química , Colágeno/imunologia , Brometo de Cianogênio , Camundongos , Ratos , Células Tumorais Cultivadas
8.
Tissue Eng ; 4(4): 415-28, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9916173

RESUMO

In the adult human, mesenchymal stem cells (MSCs) resident in bone marrow retain the capacity to proliferate and differentiate along multiple connective tissue lineages, including cartilage. In this study, culture-expanded human MSCs (hMSCs) of 60 human donors were induced to express the morphology and gene products of chondrocytes. Chondrogenesis was induced by culturing hMSCs in micromass pellets in the presence of a defined medium that included 100 nM dexamethasone and 10 ng/ml transforming growth factor-beta(3) (TGF-beta(3)). Within 14 days, cells secreted an extracellular matrix incorporating type II collagen, aggrecan, and anionic proteoglycans. hMSCs could be further differentiated to the hypertrophic state by the addition of 50 nM thyroxine, the withdrawal of TGF-beta(3), and the reduction of dexamethasone concentration to 1 nM. Increased understanding of the induction of chondrogenic differentiation should lead to further progress in defining the mechanisms responsible for the generation of cartilaginous tissues, their maintenance, and their regeneration.


Assuntos
Células da Medula Óssea/citologia , Cartilagem/citologia , Proteínas da Matriz Extracelular , Mesoderma/citologia , Adulto , Agrecanas , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Cartilagem/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Colágeno/biossíntese , Dexametasona/farmacologia , Matriz Extracelular/metabolismo , Humanos , Lectinas Tipo C , Mesoderma/efeitos dos fármacos , Mesoderma/metabolismo , Proteoglicanas/biossíntese , Tiroxina/farmacologia , Fator de Crescimento Transformador beta/farmacologia
9.
Life Sci ; 37(24): 2237-47, 1985 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-2866437

RESUMO

Streptozotocin (STZ)-induced diabetes (8 weeks) produced a marked depressor effect in the spontaneously hypertensive rat (SHR), confirming earlier studies, but had no effect on arterial pressure of normotensive controls (WKY). We investigated the phenomenon further by examining the effects of diabetes on the activities of aortic prolyl hydroxylase (PH) and lysyl oxidase (LO), marker enzymes for collagen biosynthesis, and on the reactivity of isolated mesenteric arteries to vasoactive agents. PH and LO activities of nondiabetic SHR were greater than those of the WKY controls. Diabetes markedly reduced PH and LO activities of SHR aortae, but had no significant effect on PH and LO activities of the WKY strain. The effects of diabetes on vascular collagen biosynthetic enzymes of SHR were not associated with reductions in mesenteric arterial responsiveness or sensitivity to norepinephrine, methoxamine, serotonin or KC1. These results suggest that the depressor effect of diabetes in SHR is associated with a reduction in vascular collagen biosynthesis but not a reduction in vascular reactivity.


Assuntos
Aminoácido Oxirredutases/análise , Diabetes Mellitus Experimental/fisiopatologia , Hipertensão/complicações , Artérias Mesentéricas/efeitos dos fármacos , Pró-Colágeno-Prolina Dioxigenase/análise , Proteína-Lisina 6-Oxidase/análise , Ratos Endogâmicos SHR/fisiologia , Ratos Endogâmicos/fisiologia , Animais , Aorta/enzimologia , Pressão Sanguínea/efeitos dos fármacos , Colágeno/biossíntese , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/enzimologia , Masculino , Metoxamina/farmacologia , Norepinefrina/farmacologia , Ratos , Ratos Endogâmicos WKY , Serotonina/farmacologia , Estreptozocina
10.
J Pharm Pharmacol ; 48(7): 694-8, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8866331

RESUMO

Propagated Swaram rat chondrosarcoma cells, rabbit chrondrocytes (from articular cartilage of knee, shoulder and hip joints), and bovine nasal cartilage explant cultures were studied. Type II collagen (CII) and its peptide fragments were quantitated in cell medium and cell layer separately, using two previously developed assays; one assay employed a monoclonal antibody, C4F6, that reacts specifically with triple helical CII and the other assay used an antibody, EIE5, that reacts specifically with a peptide of CII. A time-dependent increase in the content of CII and CII-derived peptides was observed in both rat and rabbit cultures. In both culture systems the majority of the native type II collagen is found associated with the cell layer (97% in rat cultures and 73% in rabbit cultures), while the major part of the CII peptides is found in the media (73% in rat cultures, 88% in the rabbit cultures). The concentration of peptides in the media reaches approximately 2 micrograms mL-1 in both chondrocyte monolayer cultures after 4 days. The CII peptide assay employing E1E5 was well suited to quantitate articular cartilage collagen degradation in explant culture. thus it can be used to evaluate potential therapeutic agents that can modify or inhibit cartilage degradation. The assay has the added potential that it could be used in-vivo to evaluate the effectiveness of potential metalloproteinase inhibitors in animal models of osteoarthritis or in clinical trials.


Assuntos
Anti-Inflamatórios/farmacologia , Colágeno/metabolismo , Dexametasona/farmacologia , Animais , Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais/imunologia , Artrite/tratamento farmacológico , Bovinos , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Colágeno/imunologia , Ensaio de Imunoadsorção Enzimática , Immunoblotting , Coelhos , Ratos
11.
Adv Exp Med Biol ; 105: 11-28, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-569423

RESUMO

In this paper we have described all the steps needed to develop an efficient program for distributing children's fortified formulas. The easiest steps are to develop the formulas on an experimental and laboratory basis. The real obstacles lie in implementation at the national level. All that has been described applies to experience in Chile, which we consider very successful because of the acceptance of the program as well as spectacular advances in preventing malnutrition. The figures for 1977 show that combining all degrees of malnutrition in the under six age group, the prevalence is now 12.2% compared to nearly 60% found 10 years ago. This progress is due, not only to the specific program, but also to the many others that constitute the national food and nutrition policy (CONPAN, 1976). This success is due to the persistent, skilled effort of many professional and technical staff members. It is impractical to acknowledge all individual contributions here. The National Food and Nutrition Council, the National Health Service, Universities, Research Bodies, and private enterprizes have all contributed to this joint effort. The purpose of this presentation is that this experience may benefit other countries with similar problems.


Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Proteínas Alimentares , Animais , Criança , Chile , Laticínios , Manipulação de Alimentos , Indústria de Processamento de Alimentos , Humanos , Nitrogênio/metabolismo , Ratos , Glycine max , Triticum
12.
Hybridoma ; 8(2): 187-97, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2541068

RESUMO

Human monoclonal antibodies reactive with type II collagen were obtained from patients with rheumatoid arthritis and relapsing polychondritis by fusion of cells with the human-mouse myeloma analogue HMMA2.11 TG/0. Direct fusion of peripheral blood or bone marrow mononuclear cells was unsuccessful in obtaining antibody producing hybridomas although fusion efficiency was high (1 hybridoma per 25,400 mononuclear cells fused). Polyclonal, Epstein Barr Virus transformed B cell lines derived from peripheral blood and bone marrow mononuclear cells after direct transformation, in vitro secondary immunization, and/or CD8 depletion were found to produce antibodies that reacted with type II collagen. Antibody producing EBV transformed B cells were fused with the human-mouse myeloma analogue HMMA2.11 TG/0 and six separate, stable IgM antibody producing hybridomas obtained. These results demonstrate the difficulty in obtaining human monoclonal autoantibodies, particularly of IgG isotypes, using readily accessible sources of cells in patients with chronic autoimmune diseases without expansion and preselection.


Assuntos
Anticorpos Monoclonais , Colágeno/imunologia , Hibridomas/imunologia , Animais , Artrite Reumatoide/imunologia , Autoanticorpos , Fusão Celular , Transformação Celular Viral , Colágeno/classificação , Herpesvirus Humano 4 , Humanos , Imunização Secundária , Camundongos , Policondrite Recidivante/imunologia
13.
Rev Biol Trop ; 26(1): 153-63, 1978 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-375326

RESUMO

A sanitary microbiological survey of fresh and processed fish on sale in Guatemalan markets and supermarkets was carried out. Samples of tables, floor and freezer surfaces, and of the water, ice and liquid drippings of the different stands were also taken and analyzed. Aerobic counts exceeded 10(6)/g in 72% of the samples, and 16% had more than 40 fecal coliforms/g. Coagulase-positive Staphylococcus aureus were never higher than 100/g in fish. The bacterial counts were higher in the ice and liquid drippings.


Assuntos
Escherichia coli/isolamento & purificação , Microbiologia de Alimentos , Carne/normas , Staphylococcus aureus/isolamento & purificação , Animais , Peixes , Manipulação de Alimentos , Inspeção de Alimentos , Guatemala
17.
Pure Appl Chem ; 14(2): 215-26, 1967.
Artigo em Inglês | MEDLINE | ID: mdl-6037238
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