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1.
J Dairy Sci ; 100(10): 8372-8384, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28780107

RESUMO

Lameness severely impairs cattle's locomotion, and it is among the most important threats to animal welfare, performance, and productivity in the modern dairy industry. However, insight into the pathological alterations of claw biomechanics leading to lameness and an understanding of the biomechanics behind development of claw lesions causing lameness are limited. Biplane high-speed fluoroscopic kinematography is a new approach for the analysis of skeletal motion. Biplane high-speed videos in combination with bone scans can be used for 3-dimensional (3D) animations of bones moving in 3D space. The gold standard, marker-based animation, requires implantation of radio-opaque markers into bones, which impairs the practicability for lameness research in live animals. Therefore, the purpose of this study was to evaluate the comparative accuracy of 2 noninvasive, markerless animation techniques (semi-automatic and manual) in 3D animation of the bovine distal limb. Tantalum markers were implanted into each of the distal, middle, and proximal phalanges of 5 isolated bovine distal forelimbs, and biplane high-speed x-ray videos of each limb were recorded to capture the simulation of one step. The limbs were scanned by computed tomography to create bone models of the 6 digital bones, and 3D animation of the bones' movements were subsequently reconstructed using the marker-based, the semi-automatic, and the manual animation techniques. Manual animation translational bias and precision varied from 0.63 ± 0.26 mm to 0.80 ± 0.49 mm, and rotational bias and precision ranged from 2.41 ± 1.43° to 6.75 ± 4.67°. Semi-automatic translational values for bias and precision ranged from 1.26 ± 1.28 mm to 2.75 ± 2.17 mm, and rotational values varied from 3.81 ± 2.78° to 11.7 ± 8.11°. In our study, we demonstrated the successful application of biplane high-speed fluoroscopic kinematography to gait analysis of bovine distal limb. Using the manual animation technique, kinematics can be measured with sub-millimeter accuracy without the need for invasive marker implantation.


Assuntos
Fluoroscopia/veterinária , Membro Anterior/diagnóstico por imagem , Marcha/fisiologia , Imageamento Tridimensional/veterinária , Animais , Fenômenos Biomecânicos , Bovinos , Doenças dos Bovinos/diagnóstico por imagem , Fluoroscopia/métodos , Membro Anterior/fisiologia , Imageamento Tridimensional/métodos , Coxeadura Animal/diagnóstico por imagem , Locomoção/fisiologia , Pesquisa , Tomografia Computadorizada por Raios X/veterinária
2.
Ann Oncol ; 24 Suppl 8: viii63-viii68, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24131973

RESUMO

BACKGROUND: Epithelial ovarian cancer (EOC) patients with BRCA mutations have better prognosis than nonhereditary cases matched for histology and stage and age at diagnosis, especially Ashkenazi Jews (AJ). MATERIALS AND METHODS: We retrospectively reviewed data on 700 highly ethnically heterogeneous patients diagnosed with stage Ic-IV EOC and evaluated for BRCA status between 1995 and 2009 in American, Israeli, and Italian medical centers. RESULTS: The ethnicities of the 190 patients (median age 55.5 years, range 31-83 years) were AJ, Jewish non-Ashkenazi, Caucasian, African-American, Hispanic, or unknown. Ninety were BRCA1/2 carriers (71 BRCA1 and 19BRCA2). The most common mutations in AJ and non-AJ origins were 185delAG and 6174delT. Non-Jewish Caucasians exhibited the widest variation (>20 mutation subtypes). BRCA carriers had significantly prolonged median overall survival (93.6 months) compared with noncarriers (66.6 months; 95% confidence interval 44.5-91.7, P = 0.0081). There was no difference in progression-free survival. CONCLUSIONS: Our data demonstrate a wide variety of BRCA mutations in a highly ethnically diverse EOC population, and confirm that EOC BRCA mutation carriers have better prognosis with longer median survival than patients with nonhereditary disease. The contribution of unclassified BRCA variants to cancer etiology remains undetermined.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Epiteliais e Glandulares/terapia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Adulto , Negro ou Afro-Americano/genética , Idoso , Idoso de 80 Anos ou mais , Carcinoma Epitelial do Ovário , Intervalo Livre de Doença , Etnicidade/genética , Feminino , Hispânico ou Latino/genética , Humanos , Judeus/genética , Pessoa de Meia-Idade , Mutação , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Prognóstico , Resultado do Tratamento , População Branca/genética
3.
Rev Med Brux ; 34(6): 485-90, 2013.
Artigo em Francês | MEDLINE | ID: mdl-24505869

RESUMO

Munchausen's syndrome is classified as a chronic factitious disorder with predominant physical signs and symptoms. Several symptoms are specific to this disorder, such as travelling and pseudologia fantastica. Others symptoms, such as multiple physical complaints with no organic substrate, are shared with somatoform disorders. We report a case showing how difficult it is to diagnose a Munchausen syndrome. We discuss also the opportunity to classify such a syndrome as a factitious disorder. Indeed, several authors suggest classifying Munchausen syndrome as a subtype of somatoform disorders, as those two disorders share a lot of characteristics.


Assuntos
Síndrome de Munchausen/diagnóstico , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Síndrome de Munchausen/etiologia , Transtornos Somatoformes/diagnóstico
4.
Diabetologia ; 55(4): 1048-57, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22246375

RESUMO

AIM/HYPOTHESIS: Glucocorticoid hormones (GCs) are widely used to treat a variety of inflammatory and immune diseases. However, their long-term administration is associated with adverse metabolic effects, including glucose intolerance and diabetes. Our objective was to elucidate the mechanisms by which GCs affect beta cell survival with a specific emphasis on the role of the thioredoxin-interacting protein (TXNIP) in beta cell apoptosis. METHODS: Human and mouse islets, together with MIN6 beta cells, were exposed to dexamethasone (Dex) and apoptosis was assessed by measuring the percentage of sub-G1 cells, the appearance of cleaved caspase-3 or by using a TUNEL assay. Dex-upregulated expression of Txnip mRNA was analysed by real-time PCR, and GC-modulated production and modification of proteins were determined by western blotting. RESULTS: We provide evidence that TXNIP, a negative regulator of the antioxidant thioredoxin (TRX), is strongly induced in beta cells by GCs and that its induction is dependent on p38 mitogen-activated protein kinase (MAPK) activation. TXNIP downregulation by RNA interference, overexpression of the radical scavenger TRX1 or elevation of intracellular cAMP levels attenuated the Dex-mediated apoptosis. Dex-induced Txnip expression and beta cell apoptosis are mediated by the glucocorticoid receptor (GR), as the GR antagonist RU486 fully abolishes these effects. CONCLUSIONS/INTERPRETATION: Altogether, our data suggest TXNIP as a novel mediator of GC-induced apoptosis in beta cells and further contribute to our understanding of beta cell death pathways.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Células Secretoras de Insulina/metabolismo , Animais , Apoptose/fisiologia , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Camundongos , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Int Dent J ; 62(4): 169-74, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23016998

RESUMO

The implementation of a new paradigm for caries management is necessary for the profession to respond effectively to changing population health needs. The FDI Global Caries Initiative (GCI) is a 10 year programme aimed at developing and implementing a new paradigm for caries management, one that would contribute to a common vision of health. The article reviews the global health policy landscape and examines how it might influence and shape the implementation of the GCI.


Assuntos
Cárie Dentária/prevenção & controle , Saúde Global/tendências , Política de Saúde/tendências , Promoção da Saúde/métodos , Saúde Bucal/tendências , Humanos , Cooperação Internacional , Prevenção Primária , Prevenção Secundária , Organização Mundial da Saúde
6.
Pharmeur Bio Sci Notes ; 2021: 157-166, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34751647

RESUMO

The European Pharmacopoeia (Ph. Eur.), includes both individual monographs on essential oils and a general monograph that covers all essential oils for pharmaceutical use, whether covered by an individual monograph or not. The individual monographs generally describe gas chromatography as a first identification test, while thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) methods are included in the second identification series. To comply with Ph. Eur. general chapter 2.8.25. High-performance thin-layer chromatography of herbal drugs and herbal drug preparations, HPTLC parameters must be standardised. Currently, 18 of the 32 monographs on essential oils feature the same TLC/HPTLC method, but differ in terms of the other conditions described. A single, standardised chromatographic system with a system suitability test (SST) and intensity markers for all 32 essential oils covered by individual monographs would be desirable, particularly for pharmacies and other users that cannot perform gas chromatography for financial reasons. To this end, this paper describes the development of a general HPTLC method for the identification of essential oils in compliance with general chapter 2.8.25. The method proposes the use of ethyl acetate, toluene (5:95 V/V) as mobile phase, isoeugenol/isoeugenyl acetate for the SST, and a combination of one alcohol (either borneol or linalool) and one ester (either linalyl acetate or bornyl acetate) as intensity markers.


Assuntos
Óleos Voláteis , Plantas Medicinais , Cromatografia em Camada Fina
7.
Pharmeur Bio Sci Notes ; 2021: 1-25, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33734082

RESUMO

Following a decision of the European Pharmacopoeia (Ph. Eur.) Commission, the Traditional Chinese Medicines (TCM) Working Party started a pilot phase to examine the suitability of a high-performance thin-layer chromatography (HPTLC) minimum content test as an alternative to the classical assay in TCM monographs. This approach was evaluated with two TCM herbal drugs: Fritillaria thunbergii bulbs (FTB) and Corydalis rhizome (CYR). Firstly, the existing HPTLC methods were optimised for both drugs. The new methods were applied to the evaluation of multiple samples, and acceptance criteria for the identification, following Ph. Eur. chapter 2.8.25. High-performance thin-layer chromatography of herbal drugs and herbal drug preparations, were set. The HPTLC test for minimum content of markers was then developed and validated. In this test, the intensity of the marker zone in the fingerprint of the sample is compared to the corresponding zone in the reference solution, which has a concentration giving an intensity equivalent to the acceptance criterion. This test gives a pass or fail result rather than a content and can be performed visually (on the images) or by software (using peak profiles from images; PPI). Reproducibility of the HPTLC methods was evaluated in a collaborative trial including six laboratories. In summary, results for FTB from five laboratories were in agreement. The remaining laboratory did not pass the identification of the samples. For CYR, all laboratories presented the same results for identification. In the test for minimum content, one borderline sample passed in four laboratories and failed in two. All laboratories reached similar conclusions for the other seven samples. The HPTLC methods proposed offer a simplified approach to evaluating identity and minimum content of TCM drugs in a single analysis.


Assuntos
Fritillaria , Preparações Farmacêuticas , Cromatografia em Camada Fina , Medicina Tradicional Chinesa , Reprodutibilidade dos Testes
8.
J Exp Med ; 148(1): 223-34, 1978 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-78958

RESUMO

We have (a) screened a variety of cell lines and body fluids for plasminogen activators and (b) studied the activity of proteases bound to alpha2- macroglobulin after exposing the complexes to partial degradation and/or denaturing procedures to unmask proteolytic activity. The respective results show (a) that the plasminogen activators in urine and cell culture media are generally of lower molecular weight than those in plasma; and (b) that proteases bound to alpha2-macroglobulin recover the ability to attack macromolecular substrates after exposure to sodium dodecyl sulfate while retaining the electrophoretic mobility of the protease inhibitor complex. This indicates that the protease and inhibitor are probably linked by covalent bonds. In contrast, other complexes formed between proteases and inhibitors of lower molecular weight (such as soybean or Kunitz inhibitors) are fully dissociated by sodium dodecyl sulfate (SDS). The experiments described were based on a new procedure for detecting proteolytic enzyme activity in SDS-polyacrylamide gels. The method relies on solutions of nonionic detergents for extracting SDS, after which the electrophoretic gel is applied to an indicator gel consisting of a fibrin- agar mixture. The method is sensitive, permitting the detection of proteinases in less than 1 mul of fresh plasma, and it is effective for resolving small differences in molecular weight. The procedure can be quantitated and, with minor modifications appropriate to each particular system, it has been applied to a broad spectrum of serine enzymes and proenzymes, including some that function in the pathways of fibrinolysis, coagulation and kinin-generation. Other potential applications appear likely.


Assuntos
Líquidos Corporais/enzimologia , Peptídeo Hidrolases/análise , Inibidores de Proteases , Ágar , Animais , Linhagem Celular , Meios de Cultura , Eletroforese em Gel de Poliacrilamida , Humanos , Métodos , Peso Molecular , Peptídeo Hidrolases/metabolismo , Ativadores de Plasminogênio/análise , alfa-Macroglobulinas/metabolismo
9.
J Exp Med ; 145(2): 429-37, 1977 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-833546

RESUMO

Macrophages obtained from the peritoneal cavity of untreated mice do not ordinarily synthesize plasminogen activator. However, induction of enzyme synthesis and secretion occurs when such macrophages are cultured in presence of conditioned medium from Con A-stimulated spleen cells. Plasminogen activator production by macrophages from endotoxin or thioglycollate medium-injected mice, which spontaneously secrete substantial amounts of the enzyme, is also markedly increased in presence of such conditioned medium. These results suggest that macrophage plasminogen activatory production may be regulated in part by lymphocytes. They provide further evidence to link macrophage plasminogen activator with cell migration and inflammation, and also support the view that in macrophages, as in certain other cell types, synthesis and secretion of this enzyme are under hormonal control.


Assuntos
Ativação Linfocitária , Linfocinas/farmacologia , Macrófagos/efeitos dos fármacos , Ativadores de Plasminogênio/biossíntese , Animais , Células Cultivadas , Concanavalina A/farmacologia , Dexametasona/farmacologia , Endotoxinas/farmacologia , Indução Enzimática , Linfonodos/imunologia , Macrófagos/citologia , Macrófagos/metabolismo , Manosídeos/farmacologia , Camundongos , Fagocitose , Baço/imunologia , Tioglicolatos/farmacologia , Timo/imunologia
10.
J Exp Med ; 147(3): 745-57, 1978 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-632749

RESUMO

Serine proteases or esterases released from cell cultures into the growth medium were converted to radioactive derivatives by active site labeling with tritiated DFP, both in the presence and absence of other competing active site reagents. The individual labeled enzymes were then identified by SDS-polyacrylamide gel electrophoresis and scintillation autoradiography. Conditioned medium from embryonal mouse fibroblasts transformed by mouse sarcoma virus contained five serine enzymes that were not present in medium from normal cells; two serine enzymes were released by both cell types, and one serine enzyme was found only in medium from normal cells. Two of the enzymes released by transformed cells were identified as plasminogen activators; these accounted for most of the serine enzyme labeling in transformed culture media and for most of the serine enzyme difference between normal and transformed cultures. The culture fluids from two cell strains of human neoplastic origin were examined by the same method. A rhabdomyosarcoma strain released eight serine enzymes (mol wt ranging from 22,500 to 102,000), four of which were plasminogen activators; seven serine enzymes (mol wt 26,000-102,000), including two plasminogen activators, were detected in medium from human melanoma cultures. In terms of electrophoretic mobility two of the plasminogen activators from rhabdomyosarcoma were identical with those from melanoma cultures, while the remaining two rhabdomyosarcoma activators coincided with activators found in commerical urokinase.


Assuntos
Transformação Celular Neoplásica/metabolismo , Neoplasias/enzimologia , Peptídeo Hidrolases/metabolismo , Sítios de Ligação , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Esterases/metabolismo , Humanos , Isoflurofato/metabolismo , Cinética , Ativadores de Plasminogênio/metabolismo , Serina , Inibidores da Tripsina/farmacologia
11.
J Exp Med ; 149(1): 284-9, 1979 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-762495

RESUMO

Polymorphonuclear leukocytes purified from human peripheral blood synthesized RNA and proteins when placed in cell culture. Autoradiography of the cultured cells revealed that a majority of mature PMNs were engaged in macromolecule synthesis, and an analysis of newly synthesized proteins by SDS-polyacrylamide gel electrophoresis showed that many different polypeptide chains were synthesized by these cells. The rate of [3H]uridine incorporation and the pattern of newly synthesized proteins were modulated by Con A and glucocorticoids. These results suggest that in spite of their short lifetime and a large performed enzymatic apparatus, mature PMNs retain a substantial capacity for RNA and protein synthesis; and, further, that modulation of macromolecule synthesis forms part of the mechanism by which PMNs respond to inflammatory and anti-flammatory stimuli.


Assuntos
Proteínas Sanguíneas/biossíntese , Neutrófilos/metabolismo , RNA/biossíntese , Células Cultivadas , Concanavalina A/farmacologia , Dexametasona/farmacologia , Humanos
12.
J Exp Med ; 139(4): 834-50, 1974 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-4816302

RESUMO

Cultured thioglycollate-stimulated peritoneal macrophages synthesize, accumulate, and continuously release high levels of plasminogen activators for at least 4 days whereas cultures of unstimulated macrophages do not; the higher specific catalytic activity of released vs. cell-associated enzyme suggests that the plasminogen activators are actively secreted. The major macrophage plasminogen activator is a serine protease of mol wt 48,000, and thus resembles the comparable enzyme released by virally transformed fibroblasts. Macrophages release a second plasminogen activator of mol wt 28,000 that is also a serine enzyme. The secretion products released by stimulated and unstimulated macrophages have been compared by SDS-polyacrylamide gel electrophoresis after chemical labeling with (3)H-DFP or biosynthetic labeling with (14)C-amino acids. These procedures show that some proteins are formed in both cultures, whereas others are uniquely secreted by each type of macrophage. The serine enzymes released by the two kinds of macrophages differ in specificity and electrophoretic mobility.


Assuntos
Macrófagos/enzimologia , Peptídeo Hidrolases/biossíntese , Plasminogênio , Aminoácidos/metabolismo , Animais , Radioisótopos de Carbono , Transformação Celular Neoplásica , Células Cultivadas , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática , Feminino , Fibrinólise , Isoflurofato/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos , Peso Molecular , Muramidase/biossíntese , Peptídeo Hidrolases/análise , Serina , Tioglicolatos/farmacologia , Trítio
13.
J Exp Med ; 146(6): 1693-706, 1977 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-200699

RESUMO

Purified human PMNs secrete plasminogen activator. This secretion is stimulated by Con A and low concentrations of PMA, and is inhibited by low concentrations of glucocorticoids, and by cAMP, actinomycin D, and cycloheximide. In contrast, the release of granule-bound enzymes, such as elastase, is achieved only at higher concentrations of PMA, and is not affected by any of the inhibitors that block plasminogen activator production. These results show that the production of plasminogen activatory by PMNs is controlled by agents that affect inflammations, and that this control is not shared by other lytic enzymes known to be associated with these cells. This suggests a particular role for plasminogen activator in the response pattern of PMNs and also supports the concept, previously developed for macrophages, that the secretion of this enzyme is correlated with cell migration in vivo.


Assuntos
Neutrófilos/metabolismo , Ativadores de Plasminogênio/metabolismo , AMP Cíclico/farmacologia , Dexametasona/farmacologia , Fibrinólise , Glucocorticoides/farmacologia , Elastase Pancreática/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
14.
J Exp Med ; 144(6): 1689-94, 1976 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-1003109

RESUMO

Intraperitoneal injection of asbestos fibres into mice induces the formation of exudates containing macrophages that produce plasminogen activator. Like-wise, in vitro addition of asbestos to macrophage cultures stimulates plasminogen activator secretion; the synthesis and secretion of lysozyme and lysosomal enzymes are not changed under these conditions. The enhanced secretion of plasminogen activator by macrophages exposed to asbestos is suppressed by low concentrations of anti-inflammatory steroids.


Assuntos
Anti-Inflamatórios/farmacologia , Amianto/farmacologia , Macrófagos/metabolismo , Ativadores de Plasminogênio/biossíntese , Animais , Amianto/antagonistas & inibidores , Líquido Ascítico/citologia , Células Cultivadas , Dexametasona/farmacologia , Endotoxinas/farmacologia , Lisossomos/enzimologia , Camundongos , Muramidase/metabolismo , Ativadores de Plasminogênio/metabolismo , Tioglicolatos/farmacologia
15.
J Exp Med ; 154(2): 422-31, 1981 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-6973604

RESUMO

Mouse T cell growth factor was purified from the serum-free conditioned medium of lectin-stimulated spleen cells. A 3,000-fold purification was achieved with a final yield of 12%. The purified protein, with an apparent Mr of 23,000 by sodium dodecyl sulfate polyacrylamide gel electrophoresis, was active at concentrations of 4 x 10(-11) M, both in the T cell growth factor and T cell replacing factor assays. In addition, purified T cell growth factor alone was mitogenic for spleen cells from both nude and normal mice.


Assuntos
Interleucina-2/isolamento & purificação , Linfocinas/isolamento & purificação , Animais , Cromatografia por Troca Iônica , Relação Dose-Resposta Imunológica , Eletroforese em Gel de Poliacrilamida , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C/imunologia , Camundongos Nus/imunologia , Dodecilsulfato de Sódio
16.
J Exp Med ; 154(2): 385-96, 1981 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-7196434

RESUMO

We have purified the immunoglobulins (IgG) from rabbit antisera raised against two cell lines--LLC-PK1 derived from pig kidney and from Kirsten sarcoma virus-transformed BALB/3T3--and have studied the effects of IgG on cultures of the respective target cells. The following observations were made with both cell types: (a) The addition of purified IgG produced a rapid change in morphology within 2 h. This consisted of cell rounding, agglutination, and detachment from the surface of the dish. (b) Beginning approximately 2 h after IgG addition there was a progressive rise in plasminogen activator production for 24--36 h. (c) Both the morphological change and the induction of plasminogen activator (PA) synthesis were reversible and required the continued presence of IgG for their maintenance. The increase in PA production, but not morphological change, depended on genetic transcription and translation, being inhibited by actinomycin and/or cycloheximide. (d). These effects of IgG were specific: they were not observed with preimmune or indifferent IgG and occurred only after interaction between an IgG preparation from antisera and the cells used to generate the particular antiserum. The divalent IgG fragments F(ab')2 retained fully the activities of the native IgG molecules from which they were derived.


Assuntos
Anticorpos/farmacologia , Ativadores de Plasminogênio/biossíntese , Animais , Células Cultivadas , Relação Dose-Resposta Imunológica , Imunoglobulina G/farmacologia , Coelhos/imunologia
17.
J Exp Med ; 160(3): 738-50, 1984 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-6236276

RESUMO

Antibodies to highly purified mouse interleukin 2 (IL-2) were raised in rabbits; a 1:500 dilution of antiserum completely blocked the in vitro mitogenic effect of 10(-9) M IL-2. The antisera functioned effectively to immunoprecipitate biosynthetically labeled IL-2 and the purified immunoglobulins were useful in the construction of affinity columns for the adsorption and one-step immunopurification of IL-2. The antibodies were apparently specific for IL-2 among the lymphokines, they did not block the biological effects of IL-1, IL-3, gamma-IFN, B cell stimulating factor(s), and cytotoxic T cell differentiation factor(s). When anti-IL-2 was added to the in vitro reactions, it blocked mixed leukocyte reactions (MLR) and associated lymphocyte proliferation, the in vitro generation of cytotoxic T cells, and antibody formation as assessed by erythrocyte-specific plaque-forming cells (PFC). When injected into mice, anti-IL-2 antibodies also reduced the formation of cytotoxic lymphocytes in response to allogeneic cells, suggesting that endogenous IL-2 participates in such reactions in vivo. Taken together, the results indicate that these IL-2 antibodies will be useful adjuncts in the analysis of immune response both in vivo and in vitro.


Assuntos
Anticorpos/fisiologia , Interleucina-2/imunologia , Animais , Anticorpos/administração & dosagem , Especificidade de Anticorpos , Reações Antígeno-Anticorpo , Ligação Competitiva , Precipitação Química , Citotoxicidade Imunológica , Interleucina-2/metabolismo , Interleucina-2/fisiologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Testes de Neutralização , RNA Mensageiro/metabolismo , Coelhos , Linfócitos T/imunologia , Linfócitos T Auxiliares-Indutores/imunologia
18.
J Exp Med ; 159(2): 647-52, 1984 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-6607316

RESUMO

Interleukin 2 (IL-2) is a T cell-derived lymphokine that serves as a cofactor for the in vitro response of T lymphocytes to antigen and plays an important role in regulating the growth and/or differentiation of these cells (1, 2). It has been postulated (2, 3) that IL-2 is produced by a discrete regulatory T cell subset, with its effects being exerted on a second, functionally distinct subpopulation of T cells. Cytotoxic T cells have been included in the IL-2-responsive subset (3). Several models of immune regulation have further assumed that the T lymphocyte pool is divided into a complex array of genetically preprogrammed T cell subtypes, each performing a specific regulatory or effector function (4, 5). However, recent results from several laboratories (6-8) have failed to support such a strict functional subdivision of the T cell pool. The availability of highly purified mouse IL-2 (1) prompted us to reevaluate the distinction, if any, between IL-2-producing and IL-2- responsive T cells. For this purpose, we resorted to a cell-cloning procedure using activated T lymphocytes that were maintained only for short periods in culture. T cell clones were tested for cytotoxic activity, responsiveness to IL-2, and for the capacity to produce IL-2 after appropriate stimulation. We found no evidence for the existence of a major functional subdivision involving these parameters among alloantigen-activated T cells: the majority of clones analyzed could perform all three functions.


Assuntos
Interleucina-2/biossíntese , Linfócitos T Citotóxicos/imunologia , Animais , Divisão Celular , Células Clonais/imunologia , Citotoxicidade Imunológica , Interleucina-2/fisiologia , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
19.
J Exp Med ; 147(4): 1285-90, 1978 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-650154

RESUMO

Peripheral blood leukocytes of three patients with Chédiak-Higashi syndrome (CHS) contained very low or undetectable levels of elastase, the major neutral protease in these cells. Likewise, peritoneal exudate leukocytes of beige mice (the murine counterpart of CHS) contained correspondingly reduced levels of their major neutral protease, a serine enzyme of mol wt 27,000. The elastase deficiency in CHS polymorphonuclear leukocytes might account in part for the high incidence of infections in these patients.


Assuntos
Síndrome de Chediak-Higashi/enzimologia , Camundongos Endogâmicos/sangue , Neutrófilos/enzimologia , Elastase Pancreática/deficiência , Animais , Pré-Escolar , Feminino , Humanos , Masculino , Camundongos , Peptídeo Hidrolases/sangue
20.
J Exp Med ; 139(5): 1317-28, 1974 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-4207624

RESUMO

A series of human cell lines has been examined for fibrinolysis in culture. The sera that are activating for fibrinolysis by human cells are mouse, monkey, human, horse, and bovine. Individual human sera show considerable variation in the ability to activate fibrinolysis. In common with other neoplastic or transformed mammalian and avian cell cultures, human cell lines of neoplastic origin produce substantial amounts of plasminogen activator. Several cultures of nonmalignant origin also produce plasminogen activator, whereas cultures obtained from trypsinized human embryos, or from human embryonic skin do not. The human melanoma plasminogen activators are of two kinds: a major component with a mol wt of 50,000, and a minor species with a mol wt of approximately 60,000. Both are DFP sensitive, serine proteases.


Assuntos
Transformação Celular Neoplásica , Fibrinólise , Plasminogênio/metabolismo , Animais , Bovinos , Linhagem Celular , Cães , Eletroforese em Gel de Poliacrilamida , Embrião de Mamíferos , Haplorrinos , Cavalos , Humanos , Rim , Pulmão , Melanoma , Mesotelioma , Camundongos , Peso Molecular , Osteossarcoma , Ratos , Ovinos , Pele , Especificidade da Espécie , Suínos
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