Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
J Neonatal Perinatal Med ; 16(2): 343-348, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37182845

RESUMO

INTRODUCTION: Although breast milk is considered the optimal nutrition for infants, it is also the primary cause of postnatal cytomegalovirus (CMV) infection. Preterm infants with postnatal CMV infections are susceptible to a variety of life-threatening conditions. CASE SUMMARY: Twin male infants were delivered via emergency caesarian section at 27 weeks' gestation secondary to maternal complete uterine rupture. The Apgar scores at 1 and 5 min were 1 and 1 for the older twin (Twin A) and 0 and 3 for the younger twin (Twin B). Their birth weights were 1203 g (+ 0.65SD) and 495 g (- 3.79SD) respectively. On day 41, laboratory blood test results for Twin B showed a moderate elevation in C-reactive protein (CRP), thrombocytopenia. CMV quantitative polymerase chain reaction (qPCR) tests in Twin B's urine and blood as well as in the mother's breast milk were positive, but stored, dried umbilical cord CMV qPCR tests were negative. Twin B was diagnosed with a postnatal CMV infection secondary to infected breast milk and ganciclovir was commenced on day 52. Treatment was switched to valganciclovir at 74 days of age, but a negative CMV-DNA level in the blood was not achieved. Postnatal CMV infection in this infant led to an exacerbation of pre-existing bronchopulmonary dysplasia (BPD) and he demised at 182 days of age. CONCLUSION: Postnatal cytomegalovirus infections may lead to exacerbations of BPD. Early use of raw breast milk in preterm infants should be done with careful consideration of this potential complication.


Assuntos
Displasia Broncopulmonar , Infecções por Citomegalovirus , Lactente , Feminino , Gravidez , Recém-Nascido , Masculino , Humanos , Leite Humano , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Recém-Nascido Prematuro , Estudos Prospectivos , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/diagnóstico , Citomegalovirus , Transmissão Vertical de Doenças Infecciosas
2.
Eur J Vasc Endovasc Surg ; 50(6): 738-43, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26427847

RESUMO

OBJECTIVE/BACKGROUND: Recently, the indications for thoracic endovascular aortic repair (TEVAR) have been expanding, and the applicability of TEVAR for acute type B aortic dissection (TBAD) is proposed with regard to the high mortality of open surgery for chronic TBAD. TEVAR in the acute phase may lead to remodeling of the false lumen (FL), but it is controversial whether it completely resolves the aortic expansion in the chronic phase. In this study, operative results and the relationship between FL status and the time before surgical intervention were retrospectively analyzed. METHODS: From January 2008 to September 2013, 234 patients underwent open surgery for chronic TBAD. Most patients were on left heart bypass. By considering Japanese aortic disease treatment guidelines and the smaller physique of Japanese patients, operative indications were aneurysm >50 mm in diameter or rapid aneurysm enlargement of >5 mm in a 6 month period. RESULTS: In 180 cases, the FL was patent. The mean interval between onset of TBAD and operation was 61 ± 54 months. There was no significant difference between patients in the patent FL group and those in the thrombosed FL group (p = .44). Mean ratio of FL diameter to maximum aortic diameter (FL/AD) was 0.64 ± 0.21. There was no correlation between FL and AD before the operation (r = .12). Descending thoracic aortic replacement (DTAR) was performed in 127 cases and thoracic ascending aortic replacement (TAAR) in 107 cases (Crawford type I, n = 9; Crawford type II, n = 65; Crawford type III and IV, n = 22, respectively; Safi type V, n = 11). The overall operative mortality was 6.8%: 3.9% (5/127) for DTAR and 10.3% (11/107) for TAAR. The three year survival was 86.7, and the freedom from re-intervention rate was 97.0%. CONCLUSION: Enlargement of uncomplicated TBAD in the chronic phase was poorly related to FL status and the results of open repair have improved. However, further prospective study is necessary.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Idoso , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/mortalidade , Dissecção Aórtica/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico , Aneurisma da Aorta Torácica/mortalidade , Aneurisma da Aorta Torácica/fisiopatologia , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Doença Crônica , Intervalo Livre de Doença , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/cirurgia , Reoperação , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tempo para o Tratamento , Resultado do Tratamento , Grau de Desobstrução Vascular
3.
Neuroradiol J ; 23(6): 690-5, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24148722

RESUMO

Pilocytic astrocytomas are classified as WHO grade I gliomas that occur predominantly in children and young adults. Reports of the tumors in elderly adults are extremely rare. We describe two cases of pilocytic astrocytoma in elderly adults, a 68-year-old man and a 71-year-old woman. Brain computed tomography (CT) and magnetic resonance imaging (MRI) revealed well-circumscribed lesions associated with contrast enhancement and minimal surrounding edema. Pathological studies revealed findings consistent with pilocytic astrocytomas. Although these tumors are rarely found in elderly adults, pilocytic astrocytomas should be considered in the differential diagnosis if the radiographic features of the tumors are characteristic of pilocytic astrocytomas.

4.
Phytochemistry ; 57(8): 1245-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11454352

RESUMO

From the leaves and branches of Fernandoa adenophylla, a lignan glycoside (fernandoside) and a phenylpropanoid glycoside (2"-O-beta-apiosylverbascoside) were isolated together with 12 known compounds. The structural elucidations were based on analyses of physical and spectroscopic data.


Assuntos
Glicosídeos/isolamento & purificação , Lignanas/isolamento & purificação , Plantas Medicinais/química , Propionatos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Glicosídeos/química , Lignanas/química , Espectroscopia de Ressonância Magnética , Folhas de Planta/química , Propionatos/química , Tailândia
5.
Pharmacol Biochem Behav ; 66(3): 661-5, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10899385

RESUMO

We investigated the in vivo effects of Vietnamese ginseng saponin (VG saponin) and its major component majonoside-R2 (MR2) on psychological stress-induced enhancement of lipid peroxidation in the mouse brain. Psychological stress exposure using a communication box system for 4 h significantly increased the content of thiobarbituric acid reactive substance (TBARS), an index of lipid peroxidation activity, in the brain. Pretreatment with VG saponin (15-25 mg/kg, PO) and MR2 (1-10 mg/kg, IP) significantly attenuated the psychological stress-induced increase in TBARS content in the brain. The aglycone of MR2 (MR2-aglycone: 1.2 mg/kg, IP), at the equivalent dose of MR2 (i.e., 3 mg/kg, IP), also produced the suppressive effect on the increase in the TBARS content. The in vivo suppressive effect of MR2 was dose dependently attenuated by flumazenil (3 and 10 mg/kg, IP), a benzodiazepine receptor antagonist, and pregnenolone sulfate (10 mg/kg, IP), a neurosteroidal negative allosteric modulator of GABA(A) receptors. These findings suggest that VG saponin and its major component MR2 have preventive effects on the psychological stress-induced brain cell membrane damage, and that the effect of MR2 is partly due to enhancement of GABA(A)-ergic systems in the brain.


Assuntos
Encéfalo/efeitos dos fármacos , Ginsenosídeos , Peroxidação de Lipídeos/efeitos dos fármacos , Panax/química , Plantas Medicinais , Saponinas/farmacologia , Estresse Psicológico/metabolismo , Animais , Anticarcinógenos/farmacologia , Anticarcinógenos/uso terapêutico , Encéfalo/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Saponinas/uso terapêutico , Estresse Psicológico/tratamento farmacológico , Tiobarbitúricos/metabolismo , Vietnã
6.
Mech Ageing Dev ; 108(1): 87-97, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10366042

RESUMO

SAMP6 mice are a murine model for senile osteoporosis, characterized by low peak bone mass seen at 4 or 5 months of age. Parathyroid hormone (PTH)-induced c-fos expression was examined in the bones, bone-marrow cells and kidney tissues of 2-month-old male SAMP6 mice. SAMP2 mice, which have a higher peak bone mass, were used as controls. The expression of c-fos in the bone peaked at 30 min after 60 microg/kg of human PTH(1-34) administration. After peaking, the expression fell quickly in SAMP2 mice. This decrease in expression was delayed in SAMP6 mice and the expression was higher at 1 h than in SAMP2 mice. The phenomenon observed in the bone appears to be tissue specific as it was not seen in the bone-marrow cells or kidney tissue. Immunohistochemical studies showed that c-Fos protein was localized to the nuclei of some of the osteocytes and a few of the osteoblasts in the cortical bone, and that osteocytes expressing c-Fos protein increased after PTH treatment. These results suggest that osteocytes might contribute to the maintenance of higher levels of c-fos expression in the bones of SAMP6 mice and may be related to cortical osteopenia in these mice by modulating bone remodeling and/or modeling.


Assuntos
Osteoporose/genética , Hormônio Paratireóideo/farmacologia , Fragmentos de Peptídeos/farmacologia , Proteínas Proto-Oncogênicas c-fos/genética , Animais , Células da Medula Óssea/metabolismo , Modelos Animais de Doenças , Fêmur/metabolismo , Fêmur/patologia , Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Rim/metabolismo , Masculino , Camundongos , Osteoporose/metabolismo , Proteínas Proto-Oncogênicas c-fos/biossíntese , Ratos , Tíbia/metabolismo , Tíbia/patologia
7.
Cancer Lett ; 147(1-2): 11-6, 1999 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-10660083

RESUMO

In the course of our continuing search for novel cancer chemopreventive agents from natural sources, several kinds of Panax plants were screened. Consequently, the ocotillol-type saponin, majonoside-R2 (MR2), was obtained from the rhizome and root of Panax vietnamensis (Vietnamese ginseng) as an active constituent. MR2 exhibited potent anti-tumor-promoting activity on two-stage carcinogenesis test of mouse hepatic tumor using N-nitrosodiethylamine (DEN) as an initiator and phenobarbital (PB) as a promoter. Further, MR2 exhibited the remarkable inhibitory effect on two-stage carcinogenesis test of mouse skin induced by nitric oxide (NO) donor/12-O-tetradecanoylphorbol-13-acetate (TPA) or peroxynitrite/TPA.


Assuntos
Anticarcinógenos/farmacologia , Ginsenosídeos , Neoplasias Hepáticas Experimentais/prevenção & controle , Panax/química , Plantas Medicinais , Saponinas/farmacologia , Neoplasias Cutâneas/prevenção & controle , Alquilantes , Animais , Anticarcinógenos/isolamento & purificação , Testes de Carcinogenicidade , Carcinógenos , Dietilnitrosamina , Feminino , Hiperplasia Nodular Focal do Fígado/induzido quimicamente , Hiperplasia Nodular Focal do Fígado/prevenção & controle , Neoplasias Hepáticas Experimentais/induzido quimicamente , Camundongos , Camundongos Endogâmicos ICR , Camundongos Endogâmicos SENCAR , Nitratos , Nitrocompostos , Papiloma/induzido quimicamente , Papiloma/prevenção & controle , Fenobarbital , Saponinas/isolamento & purificação , Neoplasias Cutâneas/induzido quimicamente , Acetato de Tetradecanoilforbol , Vietnã
8.
Biol Pharm Bull ; 21(8): 834-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9743252

RESUMO

Seven saponins (1-7) isolated from the rhizomes and roots of Panax vietnamensis were tested for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) induced by the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA), in Raji cells as a primary screening test for anti-tumor-promoters (cancer chemopreventive agents). The ocotillol-type saponin, majonoside-R2 (2), which is the major and characteristic constituent of this plant, exhibited a significant inhibitory effect on EBV-EA activation. Furthermore, the cell cycle analysis of 2 on Raji cells was also examined and strong inhibition was observed on the effect of the cell cycle induced by TPA. Compound 2 showed potent anti-tumor-promoting activity in two-stage carcinogenesis tests of mouse skin using 7,12-dimethylbenz[a]anthracene (DMBA) as an initiator and TPA or fumonisin B1 as a promoter. Consequently, these results suggest that majonoside-R2 (2) could be a valuable chemopreventive agent against chemical carcinogenesis.


Assuntos
Anticarcinógenos/farmacologia , Fumonisinas , Ginsenosídeos , Saponinas/farmacologia , Animais , Antígenos Virais/efeitos dos fármacos , Ácidos Carboxílicos/antagonistas & inibidores , Masculino , Camundongos , Camundongos Endogâmicos ICR , Papiloma/prevenção & controle , Neoplasias Cutâneas/prevenção & controle , Acetato de Tetradecanoilforbol/antagonistas & inibidores
9.
Acta Orthop Scand ; 69(3): 237-42, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9703395

RESUMO

We retrospectively reviewed hip arthroplasties in 13 patients (15 hips), in whom we had used apatite-wollastonite (A-W) glass ceramic together with auto- or allograft for augmentation of severe bone deficiency. 11 cemented sockets and 4 stem revisions were included and followed for 2-9.6 years. There were no radiolucent lines between A-W glass ceramic and surrounding bone, and remodeling of the bone graft containing A-W glass ceramic was observed. No migration of cemented sockets was seen except in 1 case, which was revised. In this case, direct bonding between bone and A-W glass ceramic granules was present histologically. In 4 stem revisions, 5 mm subsidence occurred in 1 case. However, the stem became stable and remodeling of the grafted bone occurred. An artificial bone material, such as A-W glass ceramic, can be used under high-load conditions, because of its good mechanical properties.


Assuntos
Apatitas , Artroplastia de Quadril/métodos , Substitutos Ósseos , Cerâmica , Ácido Silícico , Adulto , Idoso , Artroplastia de Quadril/efeitos adversos , Cimentos Ósseos , Transplante Ósseo , Feminino , Seguimentos , Migração de Corpo Estranho/diagnóstico por imagem , Migração de Corpo Estranho/etiologia , Articulação do Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Osseointegração , Falha de Prótese , Radiografia , Reoperação , Estudos Retrospectivos , Transplante Autólogo , Transplante Homólogo
10.
J Bone Miner Res ; 12(5): 847-54, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9144352

RESUMO

High levels of immunoreactive and biologically active parathyroid hormone-related peptide (PTHrP) were detected in synovial fluids from patients with osteoarthritis (OA) and rheumatoid arthritis (RA). The levels of PTHrP immunoreactivity in synovial fluids, measured by a two-site immunoradiometric assay (IRMA) which detects hPTHrP(1-72) or longer peptides and a radioimmunoassay (RIA) specific to the carboxy-terminal portion of hPTHrP, were 3.2 +/- 0.3 pmol of hPTHrP(1-86)/l and 61 +/- 7.0 pmol of hPTHrP(109-141)/l in OA patients (mean +/- SE, n = 23), and 4.8 +/- 0.8 pmol of hPTHrP(1-86)/l and 164 +/- 30 pmol of hPTHrP(109-141)/l in RA patients (n = 26). Synovial fluid PTHrP levels distributed above the normal plasma reference ranges in each assay (0.7-2.6 pmol of hPTHrP(1-86)/l; 16-60.6 pmol of hPTHrP(109-141)/l). After concentration using sequential cation-exchange and reverse-phase chromatography, synovial fluid exhibited the activity that stimulated cyclic adenosine monophosphate (cAMP) accumulation in osteoblastic ROS 17/2.8 cells expressing PTH/PTHrP receptors. The cAMP accumulation activity in synovial fluid was sensitive to coincubation with excess hPTHrP(3-40), a PTH/PTHrP receptor antagonist, and was completely neutralized by preincubation with a monoclonal antibody specific to hPTHrP but not PTH. Immunohistochemical analysis of RA synovium revealed that PTHrP was localized in fibroblast-like cells in the synovial pannus invading articular cartilage. Our data show that PTHrP is produced locally by the diseased synovial tissue and released into synovial fluid at high concentrations, allowing us to hypothesize that PTHrP plays a novel role as a paracrine/autocrine factor in the pathology of OA and RA.


Assuntos
Artrite Reumatoide/metabolismo , Osteoartrite/metabolismo , Hormônio Paratireóideo/análise , Proteínas/análise , Líquido Sinovial/química , Idoso , Linhagem Celular , Feminino , Humanos , Imuno-Histoquímica , Ensaio Imunorradiométrico , Masculino , Pessoa de Meia-Idade , Proteína Relacionada ao Hormônio Paratireóideo , Membrana Sinovial/química
11.
Planta Med ; 61(5): 409-13, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7480200

RESUMO

Examined in vitro were the effects of some triterpenoids from Panax (Araliaceae) and Glycyrrhiza (Leguminosae) spp. on the sensitivity to daunomycin (DAU) and vinblastine (VBL) of adriamycin (ADM)-resistant P388 leukemia cells (P388/ADM), which were resistant to multiple anticancer drugs. Quasipanaxatriol, 20(S)-protopanaxatriol, ginsenoside Rh2, and compound K greatly enhanced the cytotoxicity of the anti-cancer drugs in P388/ADM cells. The extent of enhancement was different among the triterpene compounds; the 4- to 46-fold increase in DAU cytotoxicity was observed in P388/ADM cells in the presence of non-toxic or marginally toxic concentrations of individual compounds, while those for VBL were in the ratios of 2- to 37-fold. The maximum increase in cytotoxicity was observed with 50 microM quasipanaxatriol; the resistance indices defined to be the ratios of the IC50 values for P388/ADM and P388 parental cells decreased from 79 to 1.7 and from 180 to 4.9 in the cases of DAU and VBL, respectively. The reversal of DAU resistance in P388/ADM by quasipanaxatriol could be explained by the effective accumulation of the drugs mediated by the DAU-efflux blockage.


Assuntos
Daunorrubicina/farmacologia , Leucemia P388/patologia , Triterpenos/farmacologia , Vimblastina/farmacologia , Animais , Transporte Biológico , Daunorrubicina/metabolismo , Daunorrubicina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Fabaceae/química , Feminino , Leucemia P388/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Panax/química , Plantas Medicinais , Células Tumorais Cultivadas , Vimblastina/uso terapêutico
12.
Planta Med ; 60(3): 240-3, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8073091

RESUMO

The effects of some triterpenoid saponins on glucose transport in Ehrlich ascites tumor (EAT) cells were examined by measuring 2-deoxy-D-glucose (2-DG) uptake. The correlation of the effects with those on the growth of a human T-cell line (MT-4) and the replication of human immunodeficiency virus in MT-4 cells was also studied. Chikusetsusaponin Ia isolated from rhizomes of Panax japonicus C. A. Meyer (Araliaceae) inhibited the 2-DG uptake (IC50 = 76.3 microM) in a competitive fashion with respect to 2-DG (Ki = 0.32 mM) and the growth of MT-4 cells with CC50 of 84.4 microM, whereas it did not show any significant anti-HIV-1 activity. In contrast, zingibroside R1 isolated from rhizomes of Panax zingiberensis Wu et Feng (Araliaceae) showed some anti-HIV-1 activity, which was found to be superior to that of glycyrrhizin, as well as the inhibitory effects on the 2-DG uptake by EAT cells (IC50 = 91.3 microM) and the growth of MT-4 cells (CC50 = 46.2 microM).


Assuntos
Antineoplásicos/farmacologia , Antivirais/farmacologia , Glucose/farmacocinética , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , Masculino , Camundongos , Células Tumorais Cultivadas
13.
Bone Miner ; 25(3): 167-82, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8086856

RESUMO

We have generated and characterized an antibody that recognizes the C-terminal sequence of the propeptide of human bone GLA protein (BGP/osteocalcin)(amino acid -26 to -1, with +1 being the amino terminus of the mature protein). The range of sensitivity of the antibody, as determined by enzyme-linked immunosorbent assay (ELISA), was 0.5-250 ng/ml. The antibody effectively recognized pro-BGP in cell layer extracts of transformed cells (KT-005), but did not recognize mature, propeptide-less BGP in the medium from the same cultures. Strong labelling was obtained using this antibody in immunoperoxidase staining or immunofluorescence of both transformed and normal human bone cells in vitro. Monensin significantly altered the intracellular pattern of labelling in immunofluorescence studies, indicating that the recognized antigen was associated with the cellular secretory pathway. We also obtained a specific and strong staining of cells in tissue sections of human fetal bone. Antibodies against the mature protein strongly stained the mineralization front, but did not stain cells to any appreciable level. Newly embedded osteocytes were the predominant cell type stained in such material, suggesting that they may represent the major of BGP in the intact tissue. These observations indicate that BGP synthesis is a late event in osteoblastic development and that antibodies generated against the propeptide sequence are a potentially powerful tool in the analysis of bone tumors and evaluation of osteoblastic differentiation.


Assuntos
Osso e Ossos/química , Proteínas de Ligação ao Cálcio/análise , Proteínas de Ligação ao Cálcio/imunologia , Precursores de Proteínas/análise , Precursores de Proteínas/imunologia , Sequência de Aminoácidos , Animais , Anticorpos/imunologia , Western Blotting , Osso e Ossos/citologia , Calcitriol/farmacologia , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Humanos , Dados de Sequência Molecular , Osteoblastos/química , Osteocalcina/análise , Osteocalcina/biossíntese , Osteocalcina/imunologia , Osteócitos/química , Osteogênese , Coelhos , Sensibilidade e Especificidade , Células Tumorais Cultivadas
14.
Biol Pharm Bull ; 17(5): 668-71, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7920430

RESUMO

To search for possible anti-tumor-promoters, we carried out a primary screening of 21 cucurbitane triterpenoids using an in vitro assay system. Of these triterpenoids, scandenoside R6 (6), 23,24-dihydrocucurbitacin F (14), 25-acetyl-23,24-dihydrocucurbitacin F (15), 2-O-beta-D-glucopyranosyl-23,24-dihydrocucurbitacin F (17) and cucurbitacin F (18) exhibited significant inhibitory effects on Epstein-Barr virus (EBV) activation induced by the tumor promoter, 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Further, compounds 14 and 17 exhibited remarkable anti-tumor-promotion effects on mouse skin tumor promotion in an in vivo two-stage carcinogenesis test.


Assuntos
Anticarcinógenos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Herpesvirus Humano 4/efeitos dos fármacos , Plantas Medicinais/química , Neoplasias Cutâneas/prevenção & controle , Triterpenos/farmacologia , Ativação Viral/efeitos dos fármacos , Animais , Sequência de Carboidratos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Camundongos , Camundongos Endogâmicos ICR , Dados de Sequência Molecular , Papiloma/microbiologia , Papiloma/prevenção & controle , Neoplasias Cutâneas/induzido quimicamente , Acetato de Tetradecanoilforbol/farmacologia , Triterpenos/química , Triterpenos/uso terapêutico
15.
Bone Miner ; 24(3): 245-55, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8019211

RESUMO

SAMP6 is a recently developed strain of osteoporotic mice, and SAMP2 is a control for SAMP6 and has a higher peak bone mass. The bone mass of SAMP6 was increased until 2 months of age when a lysate of cells derived from the bone marrow of SAMP2 was injected at 1 or 4 days of age, but it was not increased when the lysate was injected at 21 days of age. No effect on bone mass was observed when lysates of other cells, bovine serum albumin or heat-inactivated lysate of bone marrow-derived cells of SAMP2, were injected. The ability to increase bone mass was not in the supernatant but in the pellet obtained by ultracentrifugation (105,000 g) of the lysate of bone marrow-derived cells of SAMP2. The lysate did not change the osteoclast surface but changed the appositional bone formation. In conclusion, the lysate of cells derived from the bone marrow of SAMP2 contains factors which can increase the bone mass of SAMP6, and these factors are present in the pellet obtained by ultracentrifugation.


Assuntos
Animais Recém-Nascidos , Densidade Óssea , Células da Medula Óssea , Fêmur/patologia , Osteoporose/patologia , Animais , Desenvolvimento Ósseo , Medula Óssea/fisiologia , Densitometria , Masculino , Camundongos , Camundongos Mutantes , Osteoclastos/patologia , Especificidade da Espécie , Tetraciclina/metabolismo
16.
J Biomed Mater Res ; 28(3): 365-72, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8077251

RESUMO

The interface between apatite- and wollastonite-containing glass-ceramic (A-W GC) and bone after long-term implantation was studied by scanning and transmission electron microscopy (SEM and TEM) using rat and human specimens. First, particles of A-W GC (100-220 microns in diameter) were implanted into rat tibiae, and specimens were prepared for observation at 24, 48, 72, and 96 weeks after the operation. These long-term specimens showed an A-W GC-bone interface different from that at an earlier stage, which was investigated in our previous studies. SEM showed that the Ca-P-rich layer was wider, suggesting that leaching of ions from the A-W GC had continued even after bonding with bone. In some regions, the material particles were evidently replaced by the bone. TEM showed that the intervening apatite layer had become indistinct, and that A-W GC had intermingled with bone at the interface. In some regions, the surface of the A-W GC was degraded. These findings suggest that the surface region of A-W GC is slowly replaced by bone. Second, a human bone specimen, which included A-W GC particles (300-700 microns in diameter) implanted as a bone filler for about 75 weeks was harvested and investigated. Excellent A-W GC-bone bonding was observed, and the ultrastructure of the interface was similar to that in rats after long-term implantation. This finding demonstrated that A-W GC possibly worked in human bone in the same way as in rat bone, showing excellent bioactivity.


Assuntos
Apatitas , Materiais Biocompatíveis , Osso e Ossos/ultraestrutura , Cerâmica , Osseointegração , Próteses e Implantes , Ácido Silícico , Adulto , Animais , Remodelação Óssea , Fosfatos de Cálcio/análise , Fêmur/cirurgia , Fêmur/ultraestrutura , Displasia Fibrosa Óssea/patologia , Displasia Fibrosa Óssea/cirurgia , Humanos , Masculino , Teste de Materiais , Microrradiografia , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Ratos , Ratos Wistar
17.
Bone ; 15(2): 209-15, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8086240

RESUMO

SAM-P/6 is a recently developed strain of osteoporotic mice. In this study we tried to determine whether calcium, vitamin D3, parathyroid hormone (PTH), and estrogen modified the peak bone mass of young SAM-P/6 mice, and whether the effect of these medications persisted after treatment had been discontinued. Calcium supplement, PTH, and estrogen treatment increased the peak bone mass of SAM-P/6 mice. To clarify the process by which bone mass was increased in these treated mice, we evaluated their bone formation and resorption by histomorphometry and measured the levels of ions and serum enzymes relevant to bone metabolism. We found that bone formation was increased by calcium supplementation, and bone resorption was decreased by estrogen treatment. Furthermore, the effectiveness of calcium supplement on peak bone mass was retained after treatment had been discontinued, but the effect of estrogen treatment on peak bone mass was reduced after estrogen treatment had been discontinued. The results of this study indicate that calcium supplementation and estrogen and PTH treatment each increased peak bone mass at the midpoint of the femur of SAM-P/6, and that the effect of calcium supplementation, but not that of estrogen treatment, persisted after treatment was discontinued.


Assuntos
Densidade Óssea/efeitos dos fármacos , Cálcio/uso terapêutico , Colecalciferol/uso terapêutico , Estradiol/uso terapêutico , Osteoporose/tratamento farmacológico , Hormônio Paratireóideo/uso terapêutico , Animais , Modelos Animais de Doenças , Fêmur/efeitos dos fármacos , Fêmur/fisiopatologia , Masculino , Camundongos , Microscopia de Fluorescência , Osteoclastos/patologia , Osteoporose/patologia , Osteoporose/fisiopatologia
18.
Chem Pharm Bull (Tokyo) ; 41(12): 2129-31, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8118906

RESUMO

The effect of plant extracts on D-glucose uptake by Ehrlich ascites tumour cells was examined. Among the 23 extracts of medicinal plants, five samples inhibited, and six samples activated, the uptake significantly. From one of the active plants, Lagerstroemia speciosa, two triterpenoids, colosolic acid and maslinic acid were isolated. Colosolic acid was shown to be a glucose transport activator. Since this compound was known to have hypoglycemic activity, our simple in vitro bioassay method can at least be used as a first screening for anti-diabetic activity.


Assuntos
Carcinoma de Ehrlich/metabolismo , Glucose/metabolismo , Plantas Medicinais/química , Animais , Transporte Biológico/efeitos dos fármacos , Desoxiglucose/metabolismo , Avaliação Pré-Clínica de Medicamentos , Camundongos , Camundongos Endogâmicos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células Tumorais Cultivadas
19.
Biochem Biophys Res Commun ; 194(3): 1228-33, 1993 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-8352780

RESUMO

Estrogen depletion causes postmenopausal osteoporosis. Here we report that steady state mRNA levels of transforming growth factor-beta 1 (TGF-beta 1) and osteocalcin in bone persistently decreased and increased, respectively, in vivo in estrogen-depleted rats after ovariectomy (OVX). 21 female Wistar rats (7-month-old) were randomized and underwent OVX or sham-operation, total RNA was extracted from tibiae and assessed by Northern blot analysis. OVX induced 70-80% decrease in TGF-beta 1 mRNA levels and 2- to 3-fold increase in mRNA levels of osteocalcin compared with controls three weeks after surgery. These changes persisted up to twelve weeks post-operation. OVX caused 15% reduction in femoral bone mineral density and 2-fold elevation in serum osteocalcin levels as early as two weeks post-operation. Moreover, estrogen depletion resulted in marked decrease and increase, respectively, in steady state mRNA levels of TGF-beta 1 and osteocalcin in vitro in osteoblastic rat osteosarcoma cells, ROS 17/2.8. Our results provide the first in vivo evidence that expression of TGF-beta and osteocalcin in bone is reciprocally regulated at the transcriptional level in estrogen deficient OVX rats and suggests that TGF-beta 1 may play a role in estrogen-dependent maintenance of normal bone density.


Assuntos
Estrogênios/deficiência , Osteocalcina/biossíntese , RNA Mensageiro/biossíntese , Tíbia/metabolismo , Fator de Crescimento Transformador beta/biossíntese , Isomerases de Aminoácido/biossíntese , Isomerases de Aminoácido/genética , Animais , Densidade Óssea , Reabsorção Óssea/etiologia , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Osteocalcina/genética , Osteoclastos/metabolismo , Ovariectomia , Peptidilprolil Isomerase , Ratos , Ratos Wistar , Fatores de Tempo , Fator de Crescimento Transformador beta/genética
20.
Endocrinology ; 131(6): 2742-6, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1306984

RESUMO

Recent analysis of the structure-function relationship of human PTH-related peptide (hPTHrP) has led to the discovery that its direct inhibitory activity on osteoclastic bone resorption resides fully in the 107-111 sequence of the peptide, as assessed by a bone resorption assay using isolated rat osteoclasts. Here we report that hPTHrP-(107-111) is inactive in neonatal mouse calvariae in culture. hPTHrP-(107-111), at doses of 10(-12)-10(-6) M and incubation periods up to 96 h, did not affect either basal or agonist-stimulated 45Ca release from prelabeled neonatal mouse calvariae, while salmon calcitonin was a potent and powerful inhibitor of both basal and stimulated 45Ca release from bone. Moreover, salmon calcitonin, but not hPTHrP-(107-111), inhibited the increase in osteoclast number in hPTHrP-(1-34)-treated bones. Furthermore, hPTHrP-(107-139) also failed to inhibit 45Ca release and the hPTHrP-(1-34)-induced increase in osteoclast number in this organ culture model when tested under conditions identical to those for hPTHrP-(107-111). The addition of indomethacin to hPTHrP-(107-111)- or hPTHrP-(107-139)-treated bones was without effect, excluding the possibility that the direct inhibitory activity of these peptides on osteoclasts is ablated by a prostaglandin-mediated mechanism. Although the mechanism underlying the apparent inability of the carboxyl-terminal PTHrP fragments to inhibit osteoclastic bone resorption in neonatal mouse calvariae is unknown, it may involve the complex microenvironment of osteoclasts in intact bone, which contains a large variety of cell types other than osteoclasts.


Assuntos
Reabsorção Óssea , Osteoclastos/fisiologia , Hormônio Paratireóideo/farmacologia , Fragmentos de Peptídeos/farmacologia , Proteínas/farmacologia , Animais , Animais Recém-Nascidos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Calcitonina/farmacologia , Cálcio/metabolismo , Radioisótopos de Cálcio , Humanos , Indometacina/farmacologia , Camundongos , Técnicas de Cultura de Órgãos , Proteína Relacionada ao Hormônio Paratireóideo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA