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1.
Orthop Traumatol Surg Res ; 104(2): 251-255, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29410196

RESUMO

BACKGROUND: The human elbow maintains its stability mainly through its bony structure. Stability is enhanced by ligamentous structures. To allow the ligamento-muscular reflex, which protects against strain and stress, mechanoreceptors are embedded in the ligament. This report describes the existence and the distribution of the elbow medial collateral ligaments (MCLs) mechanoreceptors. HYPOTHESIS: The bony attachment site has the highest density of mechanoreceptors, and the anterior part has the highest density of mechanoreceptors. MATERIALS AND METHODS: Eight MCLs of elbow from fresh frozen cadavers were used. The MCLs were harvested deep to the periosteum from the medial epicondyle to the ulna. The fan-shaped ligaments were divided into six regions of interest (ROI) and stained with modified gold chloride stain. Specimens were evaluated under a light microscope. Golgi, Ruffini, and Pacinian corpuscles were found in every specimen. The number and the distribution of each mechanoreceptor in each ROI were recorded. The density of each mechanoreceptor was calculated in regards to its volume. RESULTS: Golgi, Ruffini, and Pacinian corpuscles were seen in the ligament with small nerve fibers. Ruffini corpuscles had the highest median density of all three corpuscles. The median corpuscle density was higher in the anterior than in the posterior part and higher in the bony attachment than in the mid-substance site except for Golgi corpuscle. CONCLUSION: The three typical types of mechanoreceptors were identified in human MCL with the anterior part and bony attachment as the dominant distribution site. LEVEL OF EVIDENCE: Basic Science Study.


Assuntos
Ligamentos Colaterais/citologia , Cotovelo , Mecanorreceptores/citologia , Idoso , Cadáver , Corantes , Feminino , Compostos de Ouro , Humanos , Masculino , Pessoa de Meia-Idade
2.
Animal ; 12(2): 426-433, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28724475

RESUMO

Holstein-Friesian steer beef production is renowned globally as a secondary product of the milk industry. Grass feeding is a common practice in raising Holstein steers because of its low cost. Furthermore, grass feeding is an alternative way to produce beef with a balanced n-6 to n-3 fatty acids (FAs) ratio. However, the performance and meat quality of Holstein-Friesian cattle is more likely to depend on a high-quality diet. The aim of this study was to observe whether feeding two mixed diets; a corn-based total mixed ration (TMR) with winter ryegrass (Lolium perenne) or flaxseed oil-supplemented pellets with reed canary grass haylage (n-3 mix) provided benefits on carcass weight, meat quality and FA composition compared with cattle fed with reed canary grass (Phalaris arundinacea) haylage alone. In all, 15 21-month-old Holstein-Friesian steers were randomly assigned to three group pens, were allowed free access to water and were fed different experimental diets for 150 days. Blood samples were taken a week before slaughter. Carcass weight and meat quality were evaluated after slaughter. Plasma lipid levels and aspartate aminotransferase (AST), γ-glutamyl transpeptidase (GGT), creatine kinase (CK) and alkaline phosphatase (ALP) activities were determined. Diet did not affect plasma triglyceride levels and GGT activity. Plasma cholesterol levels, including low-density and high-density lipoproteins, were higher in both mixed-diet groups than in the haylae group. The highest activities of plasma AST, CK and ALP were observed in the haylage group, followed by n-3 mix and TMR groups, respectively. Carcass weight was lower in the haylage group than in the other groups and no differences were found between the TMR and n-3 mix groups. Although the n-3 mix-fed and haylage-fed beef provided lower n-6 to n-3 FAs ratio than TMR-fed beef, the roasted beef obtained from the TMR group was more acceptable with better overall meat physicochemical properties and sensory scores. According to daily cost, carcass weight and n-6 to n-3 FAs ratio, the finishing diet containing flaxseed oil-supplemented pellets and reed canary grass haylage at the as-fed ratio of 40 : 60 could be beneficial for the production of n-3-enriched beef.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais , Óleo de Semente do Linho/farmacologia , Carne Vermelha/normas , Ração Animal/análise , Animais , Bovinos/sangue , Dieta/veterinária , Ácidos Graxos Ômega-3/análise , Lolium , Masculino , Phalaris , Zea mays
3.
Br J Cancer ; 108(6): 1245-51, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23449357

RESUMO

BACKGROUND: This phase 3 study evaluated the efficacy of new adjuvant chemotherapy (MFP), which intensified the mitomycin-C (MMC) plus short-term doxifluridine (Mf) for gastric cancer. PATIENTS AND METHODS: A total of 855 patients (424 in Mf, 431 in MFP) with pathological stage II-IV (M0) gastric cancer after D2 gastrectomy were randomly assigned to receive either Mf (MMC 20 mg m(-2), followed by oral doxifluridine 460-600 mg m(-2) per day for 3 months) or MFP (MMC 20 mg m(-2), followed by oral doxifluridine 460-600 mg m(-2) per day for 12 months with 6 monthly infusions of 60 mg m(-2) of cisplatin) chemotherapy. RESULTS: With a median follow-up of 6.6 years, there was no difference between the two groups in recurrence-free survival (RFS) (5-year RFS 61.1% in Mf and 57.9% in MFP; hazard ratio 1.10 (95% CI 0.89-1.35); P=0.39) and overall survival (OS) (5-year OS 66.5% in Mf and 65.0% in MFP; hazard ratio 1.11 (95% CI 0.89-1.39); P=0.33). CONCLUSION: Intensification of Mf adjuvant chemotherapy by prolonging the duration of oral fluoropyrimidine and adding cisplatin was safe but not effective to improve the survivals in curatively resected gastric cancer patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico , Adolescente , Adulto , Idoso , Cisplatino/administração & dosagem , Feminino , Floxuridina/administração & dosagem , Seguimentos , Gastrectomia , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida , Fatores de Tempo , Adulto Jovem
6.
Transplant Proc ; 40(8): 2832-4, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929875

RESUMO

Simultaneous liver and kidney transplantation (SLKT) is now considered the treatment of choice for patients with concurrent end-stage liver and kidney diseases. Even though the early postoperative mortality rate following SLKT is reported to be high compared to that of liver transplantation alone, the liver graft from the same donor has been argued to induce better kidney graft acceptance as evidenced by a low rate of acute renal rejection episodes. There have been many reports of a low incidence of acute renal rejection following SLKT; however, only a few cases were proven by simultaneous biopsies. The authors experienced a case of biopsy-proven isolated acute cellular rejection of the liver graft following SLKT.


Assuntos
Rejeição de Enxerto/diagnóstico , Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Transplante de Fígado/imunologia , Hemissuccinato de Metilprednisolona/uso terapêutico , Doença Aguda , Biópsia , Humanos , Inflamação , Transplante de Rim/patologia , Circulação Hepática , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
7.
Br J Radiol ; 81(967): e194-6, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18559899

RESUMO

Metastasis to the appendix is extremely rare. Moreover, metastasis from a hepatocellular carcinoma (HCC) has not been reported in the English language literature. We report a case of metastasis to the appendix from a HCC in a 50-year-old man who presented with pain in the right lower quadrant of the abdomen, representing acute appendicitis. On CT, a hypervascular mass occupying the lumen of the appendix with distension of the appendiceal tip and surrounding peritoneal seeding of the HCC were observed. This is the first report of CT findings of metastasis to the appendix from a HCC.


Assuntos
Neoplasias do Apêndice/secundário , Apendicite/etiologia , Carcinoma Hepatocelular/secundário , Neoplasias Hepáticas , Doença Aguda , Neoplasias do Apêndice/diagnóstico por imagem , Apendicite/diagnóstico por imagem , Carcinoma Hepatocelular/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
8.
Cytopathology ; 15(6): 315-20, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15606364

RESUMO

The current use of humanized monoclonal antibody trastuzumab for the treatment of patients with metastatic breast cancer has made evaluation of HER-2/neu status an important clinical issue. Chromogenic in situ hybridization (CISH), in which the DNA probe is detected with an immunohistochemistry (IHC)-like peroxidase reaction, has been recently developed for the assessment of HER-2/neu status in formalin-fixed breast cancer specimens. We have applied the technique of dual-colour CISH using HER-2/neu and chromosome 17 centromere probes in 27 cytological smears, and these cytological samples were obtained from scrapings of fresh breast tumours. We also investigated HER-2/neu amplification and protein overexpression in the corresponding surgical tissues by CISH and IHC using the monoclonal antibody CB11. Of the 27 cytological cases, HER-2/neu gene amplification was observed in nine cases that were positive cases (2+ and 3+) for IHC. Among the 13 IHC positive cases (2+ and 3+), four of them showed no gene amplification. Identical results for the CISH technique were obtained in the matched surgical samples. The scrape samples from fresh breast tumour offer a monolayer cell population that is especially suitable for CISH. This study has shown that the cytological smear might be a good alternative for the CISH test.


Assuntos
Neoplasias da Mama/genética , Hibridização In Situ/métodos , Receptor ErbB-2/genética , Biópsia , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Centrômero/genética , Cromossomos Humanos Par 17/genética , Feminino , Amplificação de Genes/genética , Técnicas de Preparação Histocitológica/métodos , Humanos , Imuno-Histoquímica , Receptor ErbB-2/análise
9.
Psychopharmacology (Berl) ; 154(4): 420-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11349397

RESUMO

RATIONALE: Previous studies indicate that chronic food restriction augments the rewarding and motor-activating effects of diverse drugs of abuse. The drugs that have so far proved susceptible to the augmenting effect of food restriction all increase synaptic concentrations of dopamine (DA). It is not known whether behavioral effects of selective, direct DA receptor agonists are also subject to the augmenting effect of food restriction. OBJECTIVES: The first objective of this study was to investigate whether the rewarding and locomotor-activating effects of the D1 agonist, A77636, and the D2 agonist, quinpirole are augmented by chronic food restriction. The second purpose was to investigate whether the augmented rewarding and locomotor-activating effects of d-amphetamine in food-restricted rats are reversed by the D1 antagonist, SCH23390. METHODS: Rewarding effects of drugs were measured in terms of their ability to lower the threshold for lateral hypothalamic self-stimulation (LHSS) using a rate-frequency method. Locomotor-activating effects were measured in terms of the number of midline crossings exhibited by rats in a shuttle apparatus. RESULTS: A77636 (1.0 and 2.5 mg/kg, i.p.) produced a greater threshold-lowering effect in food-restricted than ad libitum fed rats but produced variable effects on locomotor activity with no difference between groups. Quinpirole (0.2 and 0.5 mg/kg, i.p.) produced a marginally greater threshold-lowering effect in food-restricted rats and a dramatic locomotor response that was exclusive to food-restricted rats. The D1 antagonist, SCH23390, at a dose of 0.01 mg/kg (i.p.), had no effect on the lowering of LHSS threshold by amphetamine (0.5 mg/kg, i.p.) in ad libitum fed rats but blocked the augmentation otherwise observed in food-restricted rats. SCH23390, at a dose of 0.025 mg/kg, had no effect on locomotor activity induced by amphetamine (0.5 mg/kg) in ad libitum fed rats but blocked the augmentation otherwise observed in food-restricted rats. CONCLUSIONS: These results indicate that the augmentation of reward by food restriction extends to drugs that bypass the DA terminal and act postsynaptically. When taken together with prior immunohistochemical and behavioral findings, these results suggest that food restriction may increase the "enabling" effect of the D1 receptor on DA-mediated behaviors.


Assuntos
Adamantano/análogos & derivados , Agonistas de Dopamina/farmacologia , Antagonistas de Dopamina/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Privação de Alimentos/fisiologia , Atividade Motora/efeitos dos fármacos , Recompensa , Adamantano/farmacologia , Animais , Benzazepinas/farmacologia , Benzopiranos/farmacologia , Dextroanfetamina/farmacologia , Relação Dose-Resposta a Droga , Masculino , Atividade Motora/fisiologia , Quimpirol/farmacologia , Ratos , Ratos Sprague-Dawley , Autoestimulação/efeitos dos fármacos , Autoestimulação/fisiologia
10.
Eur J Biochem ; 267(11): 3220-5, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10824106

RESUMO

Annexin I (also called lipocortin 1) is a 37-kDa member of the annexin family of proteins. It has been proposed to be involved in the regulation of cell growth and differentiation, apoptosis, and inflammation. Previously, we have reported that annexin I displays a chaperone-like function (Kim, G.Y., Lee, H.B., Lee, S.O., Rhee, H.J. & Na, D.S. (1997) Biochem. Mol. Biol. Int. 43, 521-528). To determine the possibility that annexin I is a stress protein, we examined whether expression of annexin I and annexin I mRNA increases in response to stresses in A549 and HeLa cells. Treatments of cells with heat, hydrogen peroxide or sodium arsenite resulted in (a) an increase in annexin I and annexin I mRNA and (b) translocation of annexin I from the cytoplasm to the nucleus and perinuclear region. The annexin I gene promoter region, cloned upstream of a reporter gene, was inducible in response to heat, hydrogen peroxide, and sodium arsenite. These results indicate that annexin I serves as a stress protein and annexins may constitute a new class of stress proteins.


Assuntos
Anexina A1/biossíntese , Arsenitos/farmacologia , Regulação da Expressão Gênica , Peróxido de Hidrogênio/farmacologia , Compostos de Sódio/farmacologia , Estresse Fisiológico/metabolismo , Reagentes de Sulfidrila/farmacologia , Adenocarcinoma/patologia , Anexina A1/genética , Transporte Biológico , Núcleo Celular/metabolismo , Células Eucarióticas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Células HeLa/efeitos dos fármacos , Temperatura Alta , Humanos , Neoplasias Pulmonares/patologia , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Estresse Oxidativo , RNA Mensageiro/biossíntese
11.
Mol Pharmacol ; 57(5): 1056-63, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10779392

RESUMO

The aryl hydrocarbon receptor (AHR) is known to mediate the toxic and carcinogenic effects of polycyclic aromatic hydrocarbons and dioxins. High-affinity AHR ligands, such as 2,3,7, 8-tetrachlorodibenzeno-p-dioxin, have been shown to modify cell proliferation and differentiation. However, the mechanisms by which AHR affects cell proliferation and differentiation are not fully understood. To investigate the role of AHR in cell proliferation, mouse embryonic fibroblasts (MEFs) derived from AHR-null mice were obtained and characterized. Compared with wild-type MEFs, AHR-null cells exhibited a lower proliferation rate with an accumulation of 4N DNA content and increased apoptosis. The expression levels of Cdc2 and Plk, two kinases important for G(2)/M phase of cell cycle, were down-regulated in AHR-null MEFs. In contrast, transforming growth factor-beta (TGF-beta), a proliferation inhibitor in several cell lines, was present at high levels in conditioned medium from AHR-null MEFs. Concomitant with G(2)/M cell accumulation, treatment of wild-type MEFs with TGF-beta3 also resulted in down-regulation of both Cdc2 and Plk. Thus, overproduction of TGF-beta in AHR-deficient cells appears to be the primary factor that causes low proliferation rates and increased apoptosis. Taken together, these results suggest that AHR influences TGF-beta production, leading to an alteration in cell cycle control.


Assuntos
Fibroblastos/citologia , Fase G2/fisiologia , Mitose/fisiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Apoptose , Proteína Quinase CDC2/genética , Proteína Quinase CDC2/metabolismo , Proteínas de Ciclo Celular , Células Cultivadas , Regulação para Baixo , Embrião de Mamíferos/citologia , Fibroblastos/metabolismo , Fase G2/genética , Camundongos , Mitose/genética , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases , Proteoglicanas/farmacologia , Proteínas Proto-Oncogênicas , RNA Mensageiro/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Fatores de Crescimento Transformadores beta , Fator de Crescimento Transformador beta/metabolismo , Quinase 1 Polo-Like
12.
J Korean Med Sci ; 13(3): 286-90, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9681807

RESUMO

The matrix metalloproteinases (MMPs) have been associated with tumor cell invasion and metastasis of human cancers by mediating the degradation of extracellular matrix components. Therefore, these enzymes and their inhibitor (TIMP-2) constitute promising targets in the development of anticancer therapies. In order to investigate the correlation between expressions of TIMP-2, MMPs and clinical outcome, immunohistochemical staining of MMP-2, MMP-9, and TIMP-2 were performed on paraffin-embedded tissue sections of 15 early gastric cancers (EGC) and 15 advanced gastric carcinomas (AGC) without nodal metastasis and 15 AGC with nodal metastasis (AGCn+). MMP-2 and MMP-9 were expressed in neoplastic cell plasma membrane in 83.3% and 88% of cases of AGC, respectively with inter-tumoral variability of staining intensity. MMP-2 and MMP-9 staining were not correlated with presence of nodal metastasis or degree of invasion depth at the time of diagnosis (p>0.05). The immunoreactivity of TIMP-2 was detected in the peri-tumoral stroma. Residual benign stomach tissue showed no or weak immunoreactivity for TIMP-2 staining. Among AGC, neoplasms with diffuse and strong TIMP-2 staining have less frequent metastasis (28.6%) than cases with focal and weak (68.8%) (p<0.05). Early gastric cancer revealed diffuse and strong TIMP-2 expressions. We conclude that clinical outcome such as depth of invasion or metastasis is more closely related to the expression of TIMP-2 than the corresponding MMPs.


Assuntos
Colagenases/biossíntese , Gelatinases/biossíntese , Linfonodos/patologia , Metaloendopeptidases/biossíntese , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Inibidor Tecidual de Metaloproteinase-2/biossíntese , Humanos , Imuno-Histoquímica , Metástase Linfática , Metaloproteinase 2 da Matriz , Metaloproteinase 9 da Matriz , Estômago/enzimologia , Neoplasias Gástricas/enzimologia
13.
J Reprod Fertil ; 108(2): 313-20, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9038791

RESUMO

Accumulating evidence suggests that uterine luminal fluids contain a variety of polypeptide growth factors and cytokines that, it is speculated, have roles in the development, growth and differentiation of the uterus and, during pregnancy, in the growth and survival of the embryo. Although epidermal growth factor (EGF) has previously been identified by radioimmunoassay and immunohistochemistry in the pig uterus, there have been no detailed studies of the secreted EGF protein. EGF was therefore purified from uterine flushings and uterine fluids of nonpregnant pigs of mixed breed using a variety of ion-exchange chromatography steps. Uterine flushings and fluids contained an anionic factor(s) that at 4 degrees C competed with 125I-labelled mouse EGF for binding to EGF receptors on an endometrial carcinoma cell line and stimulated DNA synthesis in Balb/c mouse 3T3 fibroblasts. As analysed by gel filtration, uterine fluids contained a 3-6 kDa factor that stimulated 3T3 cell DNA synthesis and was a competitor of cellular 125I-labelled EGF binding. Gel filtration further revealed that uterine flushings and fluids contained, respectively, 45 kDa and 40-70 kDa moieties that were mitogenic and that bound to the EGF receptor. SDS-PAGE and western blotting using an antiserum specific for pig EGF revealed immunoreactive forms of EGF of approximately 25 kDa in partially purified uterine flushings. It is concluded that uterine secretory EGF occurs, at least in part, as high molecular mass proteins. The ability of these high molecular mass EGFs to bind to and activate the EGF receptor suggests that they may be authentic ligands for the EGF receptor in utero.


Assuntos
Fator de Crescimento Epidérmico/análise , Suínos/metabolismo , Útero/metabolismo , Animais , Western Blotting , Líquidos Corporais/química , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Feminino
14.
Biol Reprod ; 52(3): 561-71, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7538797

RESUMO

Pig uterine luminal flushings contain at least four heparin-binding growth factors (HBGF) that stimulate fibroblast [3H]thymidine incorporation. One of these factors, which appeared to be a relatively minor HBGF, was eluted from heparin affinity columns by 1.0 M NaCl and was found to compete with 125I-epidermal growth factor (EGF) for binding to an endometrial carcinoma cell line. This EGF receptor (EGF-R)-binding property was abolished by an antiserum to heparin-binding EGF-like growth factor (HB-EGF) that specifically blocks binding of HB-EGF to the EGF-R. Reverse-phase HPLC resulted in the purification of two EGF-R-binding activities correlated with 13,500 and 17,000 M(r) proteins that reacted with an antiserum raised against residues 9-26 of human HB-EGF. Uterine extracts also contained an EGF-R-binding factor that was eluted from heparin by 1.0 M NaCl and was antagonized by HB-EGF antiserum. Endometrial mRNA subjected to reverse transcriptase-polymerase chain reaction (RT-PCR) and nested PCR through the use of HB-EGF-specific primers yielded fragments of the predicted size. Cloning of the nested PCR product revealed a 380-bp porcine HB-EGF cDNA sequence that was 78-85% homologous to primate or rodent HB-EGF. HB-EGF was immunohistochemically localized primarily to the luminal epithelium in both pregnant and nonpregnant animals.


Assuntos
Endométrio/metabolismo , Fator de Crescimento Epidérmico/biossíntese , Heparina/metabolismo , Útero/metabolismo , Animais , Sequência de Bases , Western Blotting , Cromatografia de Afinidade , Cromatografia por Troca Iônica , DNA/análise , Eletroforese em Gel de Poliacrilamida , Fator de Crescimento Epidérmico/isolamento & purificação , Receptores ErbB/efeitos dos fármacos , Receptores ErbB/metabolismo , Feminino , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Imuno-Histoquímica , Técnicas In Vitro , Peptídeos e Proteínas de Sinalização Intercelular , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/isolamento & purificação , DNA Polimerase Dirigida por RNA , Ensaio Radioligante , Suínos , Timidina/metabolismo , Útero/química
15.
Biochem Mol Biol Int ; 33(2): 253-61, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7951046

RESUMO

The effects of porcine bone morphogenetic protein (BMP) on DNA and collagen synthesis in cultured rat osteogenic sarcoma cells and mink lung epithelial cells were studied and compared with the effects induced by transforming growth factor-beta 1 (TGF-beta 1). In both cells, DNA synthesis was slightly but significantly increased by BMP whereas it was notably decreased by TGF-beta 1. The inhibitory action of TGF-beta 1 overrode the activation of DNA synthesis by BMP when the cells were incubated together with TGF-beta 1 and BMP. In osteogenic sarcoma cells, collagen synthesis was enhanced by both BMP and TGF-beta 1, but the stimulatory action of BMP was weaker than that of TGF-beta 1. In epithelial cells, TGF-beta 1 increased collagen synthesis but BMP induced no significant changes. No synergistic effects of TGF-beta 1 and BMP on collagen synthesis were observed in both cells. The present study demonstrates the possibility of direct actions of BMP and TGF-beta 1 on cultured rat osteogenic sarcoma cells and mink lung epithelial cells in vitro.


Assuntos
Neoplasias Ósseas/metabolismo , Pulmão/efeitos dos fármacos , Osteossarcoma/metabolismo , Proteínas/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Animais , Proteínas Morfogenéticas Ósseas , Osso e Ossos/química , Osso e Ossos/fisiologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Colágeno/biossíntese , DNA/biossíntese , Relação Dose-Resposta a Droga , Células Epiteliais , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Pulmão/citologia , Pulmão/metabolismo , Vison , Ratos , Suínos , Células Tumorais Cultivadas
16.
Growth Factors ; 7(4): 289-96, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1306684

RESUMO

The binding of heparin-binding EGF-like growth factor (HB-EGF) to the epidermal growth factor (EGF) receptor of human endometrial carcinoma cells was compared to that of EGF using an 125I-EGF radioreceptor assay. The inhibitory effect of HB-EGF on 125I-EGF binding was reversed either in the presence of heparin (but not by chondroitin sulfate) or by pre-treating the cells with heparinase. These treatments did not affect the binding of EGF to its receptor. To map potential regions in the HB-EGF molecule that mediate its heparin-dependent interaction with the EGF receptor, HB-EGF peptides were synthesized that were non-homologous to EGF. Accordingly residues 20-25 and 36-41, but not residues 8-19, of HB-EGF were found to be (i) heparin-binding and (ii) modulators of HB-EGF (but not of EGF) binding to the EGF receptor.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Heparina/farmacologia , Fragmentos de Peptídeos/farmacologia , Polissacarídeo-Liases/farmacologia , Sequência de Aminoácidos , Ligação Competitiva , Cromatografia Líquida de Alta Pressão , Neoplasias do Endométrio/metabolismo , Feminino , Heparina Liase , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Dados de Sequência Molecular , Ensaio Radioligante , Células Tumorais Cultivadas
17.
J Biochem ; 110(5): 802-5, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1783612

RESUMO

An acid ribonuclease (optimum pH 6.0) has been purified from bovine brain in a five-step procedure. The preparation appeared homogeneous on SDS-polyacrylamide gel electrophoresis. The molecular size of the acid ribonuclease is 70 kDa and it is a dimeric protein with a subunit molecular size of 35 kDa. The acid RNase was activated by aluminum at low concentration. Preincubation of the acid RNase with 10 microM increased the specific activity of the enzyme 2.3-fold at acid pH, while the effect of aluminum was much weaker at alkaline pH under otherwise the same conditions. A stoichiometry of 1: 1 for the binding aluminum to brain acid RNase was estimated. None of the enzyme-bound aluminum was dissociated by dialysis against 50 mM HEPES, pH 7.0 at 4 degrees C for 24 h. Citrate, EDTA, NaF, and apotransferrin abolished the effects of aluminum on the enzyme. Ribonucleic acid also protected the enzyme against the activation caused by aluminum. These results suggest that accumulation of aluminum in brain may change the regulation of ribonucleic acid metabolism.


Assuntos
Alumínio/farmacologia , Encéfalo/enzimologia , Ribonucleases/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Bovinos , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Ribonucleases/efeitos dos fármacos , Ribonucleases/isolamento & purificação
18.
Eur J Biochem ; 202(1): 107-11, 1991 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-1935968

RESUMO

The effect of aluminum on alkaline ribonuclease (RNase) and RNase inhibitor, purified from bovine brain, was investigated. Incubation of alkaline RNase with aluminum interrupted binding of RNase inhibitor to alkaline RNase. A stoichiometry of 1:1 for the binding of aluminum to brain alkaline RNase was estimated, whereas no aluminum was found to be bound to the RNase inhibitor. Aluminum-bound alkaline RNase, however, retained a full alkaline RNase activity. None of the enzyme-bound aluminum was dissociated by dialysis against 50 mM Hepes, pH 7.0, at 4 degrees C for 24 h. Citrate, EDTA, NaF and apotransferrin protected the alkaline RNase against aluminum binding. Aluminum did not bind to the incubated alkaline RNase-inhibitor complex, suggesting that aluminum might compete with RNase inhibitor for the binding site. However, the data from chemical modification and spectroscopic studies indicate that it is also highly possible that aluminum binding to the enzyme induces conformational changes at or near the inhibitor-binding site, which subsequently interrupt binding of RNase inhibitor to alkaline RNase. These results suggest that accumulation of aluminum in brain might affect the regulation of RNA metabolism.


Assuntos
Alumínio/farmacologia , Encéfalo/enzimologia , Ribonucleases/metabolismo , Alumínio/metabolismo , Animais , Sítios de Ligação , Bovinos , Quelantes , Cromatografia em Gel , Histidina/química , Concentração de Íons de Hidrogênio , Lisina/química , Conformação Proteica , Ribonucleases/antagonistas & inibidores , Ribonucleases/química , Espectrofotometria
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