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1.
Osteoporos Int ; 21(1): 189-93, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19350338

RESUMO

UNLABELLED: A 60-year-old postmenopausal woman diagnosed as primary osteoporosis began to take raloxifene. The spontaneous microaggregates of platelets induced by shear stress were accelerated after the treatment, concomitant with the significant upregulation of p44/p42 mitogen-activated protein (MAP) kinase induced by adenosine diphosphate (ADP). After the cessation of raloxifene, the spontaneous microaggregates of platelets and the acceleration of ADP-induced p44/p42 MAP kinase phosphorylation was diminished. We concluded that raloxifene caused platelet hyperaggregability to shear stress and p44/p42 MAP kinase was involved in the pathological state. INTRODUCTION: A 60-year-old postmenopausal woman suffering from severe lumbago was diagnosed as primary osteoporosis with combined vertebral fractures. After the acute phase, she began to take 60 mg daily of oral raloxifene. The spontaneous microaggregates of platelets induced by shear stress were accelerated significantly after 8 weeks from the beginning of raloxifene treatment and observed at 12 weeks. RESULTS: The platelet aggregation induced by ADP was little changed; however, low doses (0.3 and 1 microM) of ADP significantly induced the phosphorylation of p44/p42 MAP kinase in the platelets obtained at 12 weeks. Although there were few subjective complaints except for paroxysmal headache, the medication was stopped with her consent to avoid any adverse effects. The spontaneous microaggregates of platelets gradually decreased after the cessation of medication. At 12 weeks after the cessation, the phosphorylation of p44/p42 MAP kinase induced by low doses of ADP was no more observed. CONCLUSION: These results strongly suggest that raloxifene caused platelet hyperaggregability to shear stress and subclinical thrombus formation in this case and that p44/p42 MAP kinase was involved in the pathological state.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/sangue , Proteína Quinase 3 Ativada por Mitógeno/sangue , Agregação Plaquetária/efeitos dos fármacos , Cloridrato de Raloxifeno/farmacologia , Plaquetas/enzimologia , Células Cultivadas , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/tratamento farmacológico , Agregação Plaquetária/fisiologia , Regulação para Cima/efeitos dos fármacos
2.
J Endocrinol ; 167(3): 493-503, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11115777

RESUMO

The syndrome of resistance to thyroid hormone (RTH) is an inherited disorder involving a mutation of the thyroid hormone receptor (TR) gene. Mutant (m) TR inhibits wild-type (wt) TR functions in a dominant negative manner, and this dominant negative effect (DNE) is a crucial factor in RTH pathogenesis. The molecular mechanism of the DNE is still unclear, although several possibilities (including competition between wt- and mTRs at the T(3) response element (TRE), sequestration of TR-associated protein(s) and titration out of functional TR) have been considered. Here we report that the DNE of mTRs is strongly correlated with their binding avidity for the retinoid X receptor (RXR), and especially for corepressor SMRT (silencing mediator for retinoid and thyroid hormone receptor), but not for the nuclear receptor corepressor, NCoR. The DNE of six natural TRs and four artificially constructed mTRs was assayed using a TR reporter gene containing TRE-DR4 (DR=direct repeat), TRE-pal (pal=palindrome) or TRE-lap (lap=inverted palindrome) in CV1 cells treated with 10 nM T(3). Of the mTRs examined, F451X (with a carboxy-terminal 11-amino-acid truncation) identified in a patient with RTH exhibited the strongest DNE on all TREs. The binding affinities between mTRs and corepressors SMRT or NCoR were quantified using a two-hybrid interference assay system consisting of VP16-TR(LBD) (LBD=ligand binding domain) and Gal4(DBD)-SMRT (DBD=DNA binding domain), or Gal4(DBD)-NCoR respectively, together with the Gal4 reporter gene. In this assay, VP16-TR(LBD) and Gal4(DBD)-SMRT (or Gal4 (DBD)-NCoR) interact with each other and trans-activate the Gal4 reporter gene. When an equal amount of mTR is coexpressed, it reduces the transcriptional activity of the reporter gene, depending on its binding avidity for a corepressor. A very strong correlation was observed between the SMRT-binding activity and the potency of the DNE among six natural mTRs and also among all mTRs, including four artificially constructed ones. The relationship between NCoR and DNE, however, was not significant. When we assayed the binding avidity of mTRs for RXR by using a two-hybrid assay system consisting of Gal4(DBD)-RXR(LBD) and VP16-TR(LBD), a significant correlation between DNE and binding avidity for the RXR was also observed. These results suggest that a corepressor plays an important role in DNE pathogenesis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Receptores dos Hormônios Tireóideos/genética , Proteínas Repressoras/metabolismo , Análise de Variância , Ligação Competitiva , Genes Dominantes , Humanos , Mutação , Proteínas Nucleares/metabolismo , Correpressor 1 de Receptor Nuclear , Correpressor 2 de Receptor Nuclear , Ligação Proteica , Receptores do Ácido Retinoico/metabolismo , Receptores dos Hormônios Tireóideos/metabolismo , Proteínas Recombinantes/metabolismo , Receptores X de Retinoides , Fatores de Transcrição/metabolismo
3.
J Endocrinol ; 167(2): 219-27, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11054635

RESUMO

Human thyroid hormone receptor (TR) is encoded by two distinct genes, TR alpha and TR beta. TR heterodimerizes with retinoid X receptor (RXR) and binds efficiently to the thyroid hormone (T(3)) response element (TRE) of target genes. In the absence of T(3), unliganded TR suppresses the basal promoter activity of positively regulated genes (silencing). Silencing mediator for retinoid and thyroid hormone receptors (SMRT) and nuclear receptor co-repressor (N-CoR) interact with unliganded TR and function as corepressor proteins. Previously, we found beta F451X with carboxyl (C)-terminal 11-amino acid deletion had stronger silencing potency than wild-type TR beta 1 and beta E449X with C-terminal 13-amino acid deletion on a subset of TREs. In the present study, to assess the isoform-specific effects of the C-terminal truncations on TR silencing, we constructed two mutant TR alpha 1s (alpha F397X and alpha E395X) with the same respective C-terminal truncations as beta F451X and beta E449X and analysed their silencing activities. Unlike beta F451X and beta E449X, alpha F397X and alpha E395X showed similarly stronger silencing potency than wild-type TR alpha 1. We further studied the abilities of wild-type and the mutant TR beta 1s and alpha 1s on RXR and co-repressor binding by a two-hybrid interference assay. beta F451X had significantly stronger abilities to bind to RXR and SMRT than did wild-type TR beta 1 and beta E449X. In contrast, wild-type TR alpha 1, alpha F397X and alpha E395X showed similar abilities to bind to RXR and SMRT. beta E449X and alpha E395X, which have identical C-terminal truncation, showed less ability to bind to N-CoR than did wild-type TR beta 1 and beta F451X and wild-type TR alpha 1 and alpha F397X respectively. These results indicate that an identical C-terminal truncation gives rise to different effects on TR beta 1 and alpha1 with respect to silencing potency, RXR binding and SMRT binding. The difference in the silencing potency among wild-type TR beta 1, beta F451X and beta E449X correlated well with the difference in the ability to bind co-repressor SMRT.


Assuntos
Regulação da Expressão Gênica/fisiologia , Receptores dos Hormônios Tireóideos/genética , Animais , Ligação Competitiva , Técnicas de Cultura de Células , Linhagem Celular , Chlorocebus aethiops , Proteínas de Ligação a DNA/metabolismo , Humanos , Mutagênese Insercional/métodos , Correpressor 2 de Receptor Nuclear , Fragmentos de Peptídeos/genética , Isoformas de Proteínas/genética , Receptores do Ácido Retinoico/metabolismo , Receptores dos Hormônios Tireóideos/química , Receptores dos Hormônios Tireóideos/metabolismo , Proteínas Repressoras/metabolismo , Receptores X de Retinoides , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo , Transfecção
4.
J Endocrinol ; 151(2): 293-300, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8958790

RESUMO

Clinical resistance to thyroid hormone (RTH) has been classified into generalized resistance to thyroid hormone (GRTH) and pituitary resistance to thyroid hormone (PRTH) types. Since similar mutations have been identified in tri-iodothyronine (T3) receptor (TR) beta gene in GRTH and PRTH, and since considerable overlap has been seen in the clinical manifestations in patients with GRTH and PRTH, two subtypes of RTH are now considered to be a continuous spectrum with the same genetic defect. A point mutation at amino acid Arg 338 to Trp (R338W) which we identified in a patient with PRTH is very interesting, since R338W has been found in several other patients with PRTH, raising the possibility that this mutation may tend to associate with a phenotype of PRTH. In our previous study, we found that R338W had relatively less impaired transcriptional potency, weaker dominant negative activity on various T3 response elements and poor homodimer formation, as compared with another GRTH mutant. In this study, to investigate the functional properties of R338W further, especially in terms of the relation between transcriptional activity and dimer formations, we introduced the R338W mutation into the mutant receptors, K443E and F451X, constructing the double mutants, R338W/K443E and R338W/ F451X. Both R338W/K443E and R338W/F451X showed negligible T3 binding and transcriptional activities. The dominant negative activities of K443E and F451X were, however, significantly weakened by introducing the R338W mutation. As a control, a double mutant G345R/K443E was constructed by introducing a point mutation, G345R, located in the same exon 9 as R338W, into the K443E mutant. Dominant negative activity did not differ between G345R/K443E and K443E. Homodimer formation was significantly reduced in the double mutants containing R338W, but not G345R. In summary, introducing the R338W mutation, but not G345R, into the mutant TR significantly weakened the dominant negative activity, despite further impairment of the T3 binding and transcriptional activities.


Assuntos
Hipófise/metabolismo , Mutação Puntual , Receptores dos Hormônios Tireóideos/genética , Síndrome da Resistência aos Hormônios Tireóideos/genética , Transcrição Gênica , Células Cultivadas , Dimerização , Humanos
5.
Mol Cell Endocrinol ; 138(1-2): 95-104, 1998 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-9685218

RESUMO

Although different expression patterns of thyroid hormone receptor (TR) alpha1 and beta1 have been reported, no essential distinction has been established in their functions. Unlike the TR beta gene, a mutation in the TR alpha1 gene has never been found in patients with resistance to thyroid hormone (RTH). Previously we found a mutant TR beta with an 11-carboxyl (C)-terminal amino acid truncation (betaF451X) in a girl with severe RTH. BetaF451X is a natural mutant with disruption of the transactivation domain, tau4, and it had very strong dominant negative activities. Based on the fact that the 46 amino acid sequence in the extreme C-terminal region is identical in TR alpha1 and TR beta, except for a C-terminal three amino acid extension of TR alpha1, we constructed a mutant TR alpha1 (alphaF397X) with the identical C-terminal truncation to betaF451X, to study functional differences between TR alpha1 and beta1. Both betaF451X and alphaF397X had negligible T3 binding and transcriptional activities even with 1 microM T3. The dominant negative activities of the mutant TRs were remarkable and T3 response element (TRE)-dependent. Co-expression of betaF451X decreased the CAT activity of either wild-type TR alpha1 or beta1 at 100 nM T3 by approximately 90% on the TRE-pal2 and 70% on DR4. AlphaF397X inhibited the transcriptional activities of both wild-type TR alpha1 and beta1 by approximately 50% on TRE-pal2 and by 60% on DR4. The dominant negative potency of betaF451X was significantly stronger than that of alphaF397X on the TRE-pal2, -DR4 and chicken lysozyme silencer F2, but similar on TRE-myosin heavy chain alpha and malic enzyme. No partiality for the TR subtypes was found in the dominant negative effects of betaF451X and alphaF397X. Co-expression with RXR enhanced the dominant negative effects of alphaF397X, but not of betaF451X. The results indicate that there are different dominant negative properties between alphaF397X and betaF451X, which are TRE-dependent, despite their identical C-terminal truncation. Deletion in the tau4 domain might affect the receptor structures of TR alpha1 and beta1 differently.


Assuntos
Receptores dos Hormônios Tireóideos/genética , Receptores dos Hormônios Tireóideos/metabolismo , Deleção de Sequência , Animais , Linhagem Celular , Galinhas , Criança , Cloranfenicol O-Acetiltransferase/genética , Dimerização , Feminino , Humanos , Muramidase/genética , Receptores do Ácido Retinoico/genética , Receptores dos Hormônios Tireóideos/química , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Sequências Reguladoras de Ácido Nucleico , Receptores X de Retinoides , Síndrome da Resistência aos Hormônios Tireóideos/genética , Fatores de Transcrição/genética , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional , Transfecção , Tri-Iodotironina/farmacologia , Tri-Iodotironina/fisiologia
6.
J Steroid Biochem Mol Biol ; 54(3-4): 163-5, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7662590

RESUMO

In the rat liver, cytochrome P450 catalyzes the hydroxylation of steroid hormones. The expression and activity of some P450 isozymes are regulated by sex steroid hormones. Steroid 21-hydroxylase activity in rat liver is provided mainly by CYP2C6. We studied the regulation of 21-hydroxylase activity by sex steroid hormones in rat primary hepatocyte culture. We added estrogens (estrone, estradiol, estriol) and androgens (testosterone, dihydrotestosterone), (ranging from 10(-9) to 10(-5)M) to the culture. The 21-hydroxylase activity was stimulated by estrogens and was suppressed slightly by androgen in a dose-related manner. The results of our studies demonstrated that sex steroid hormones act differently on 21-hydroxylase activity in rat hepatocytes and, thus, support the hypothesis that the extra-adrenal production of deoxycorticosterone from circulating progesterone is increased during pregnancy by the massive presence of estrogens.


Assuntos
Androgênios/farmacologia , Estrogênios/farmacologia , Fígado/enzimologia , Esteroide 21-Hidroxilase/metabolismo , Animais , Células Cultivadas , Masculino , Ratos , Ratos Sprague-Dawley
7.
Metabolism ; 47(9): 1083-8, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9751237

RESUMO

Protein disulfide isomerase (PDI) is an enzyme that participates in the formation of disulfide bonds. It is also known to be the subunits of some enzymes and the membrane-associated thyroid hormone-binding protein. In this study, we measured the quantitative distribution of PDI protein in rat tissues and examined the relationship between protein level and enzyme activity in PDI during fasting and refeeding. Western blotting with specific anti-PDI antiserum detected the PDI protein band of 55 kd. Among several tissues, liver contained the largest amount of PDI protein, followed by kidney and fat, in which one-third to one-fourth of the hepatic PDI protein existed. The PDI protein band was also detected in heart and muscle. Fasting for 3 days decreased PDI protein levels in rat liver by 40%; control levels were recovered after 3 days of refeeding. The same change was observed in kidney. PDI activity, measured by the scrambled ribonuclease method, did not show the parallel alteration to PDI protein level in liver and kidney. Isomerase activity decreased to 50% of control values during fasting, but did not recover by refeeding. Thyroidal status did not affect either PDI protein level or isomerase activity. These findings show that fasting and refeeding affect PDI protein and enzyme activity, and that PDI protein level does not always reflect PDI activity.


Assuntos
Jejum , Isomerases de Dissulfetos de Proteínas/metabolismo , Animais , Western Blotting , Fígado/enzimologia , Masculino , Isomerases de Dissulfetos de Proteínas/análise , Ratos , Ratos Sprague-Dawley , Hormônios Tireóideos/análise
8.
Eur J Pharmacol ; 431(2): 151-61, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11728421

RESUMO

We investigated the effects of glycyrrhizin (GL-1) and some analogues on DNA synthesis and proliferation in serum-free primary cultures of adult rat hepatocytes. The hepatocytes underwent DNA synthesis and proliferation in response to GL-1 and some analogues. The effects of these agents occurred in a time- and dose-dependent manner. The proliferative potency as judged by half-maximal effective concentrations was in the following order: 18-beta-H-glycyrrhetinic acid (GL-3; 4.5 x 10(-9) M)<18-beta-H-glycyrrhizin (GL-1; 4.4 x 10(-8) M)<18-alpha-H-glycyrrhetinic acid (GL-6; 6.0 x 10(-8) M). The analogue 18-alpha-H-glycyrrhetinic acid 3-O-beta-D-monoglucuronide (GL-5; 1.0 x 10(-7) M) weakly stimulated hepatocyte DNA synthesis and proliferation, whereas 18-alpha-H-glycyrrhizin (GL-4) and 18-beta-H-glycyrrhetinic acid 3-O-beta-D-monoglucuronide (GL-2) did not. The growth-promoting effects of GL-1, GL-3 and GL-6 were significantly inhibited at higher initial plating densities (7.0 x 10(4) and 10 x 10(4) cells/cm(2)). A monoclonal antibody against epidermal growth factor (EGF) receptor (1-100 ng/ml), but not that against EGF (1-100 ng/ml), dose-dependently inhibited glycyrrhizin- and analogue-induced hepatocyte DNA synthesis and proliferation. Specific inhibitors of growth-related signal transducers, such as genistein, PD98059 (2'-amino-3'-methoxyflavone) and rapamycin, completely blocked glycyrrhizin- and analogue-induced hepatocyte DNA synthesis and proliferation. Treatment of hepatocytes with GL-1, GL-3 and GL-6 rapidly stimulated tyrosine phosphorylation of the EGF receptor and p42 MAP kinase, which were inhibited by genistein and PD98059, respectively. These results suggest that glycyrrhizin and some analogues are primary hepatocyte mitogens that bind to EGF receptors and subsequently stimulate the receptor tyrosine kinase/mitogen-activated protein kinase pathway to induce hepatocyte DNA synthesis and proliferation.


Assuntos
Receptores ErbB/agonistas , Ácido Glicirrízico/farmacologia , Hepatócitos/efeitos dos fármacos , Inibidores de Adenilil Ciclases , Animais , Anticorpos Monoclonais/imunologia , Contagem de Células , Divisão Celular/efeitos dos fármacos , Células Cultivadas , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , DNA/biossíntese , Relação Dose-Resposta a Droga , Receptores ErbB/imunologia , Receptores ErbB/metabolismo , Ácido Glicirrízico/análogos & derivados , Ácido Glicirrízico/química , Regeneração Hepática , Masculino , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Estrutura Molecular , Fosforilação , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo
9.
Eur J Pharm Biopharm ; 52(1): 21-30, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11438420

RESUMO

The effects of the concentration and molecular weight of poly-L-arginine (poly-L-Arg) on the in vivo nasal absorption of fluorescein isothiocyanate-labeled dextran (MW, 4 kDa, FD-4) in rats were studied. When poly-L-Arg with a range of different molecular weights (MW, 8.9, 45.5 and 92.0 kDa) was applied intranasally at various concentrations, the bioavailability (F(0-9 h)) of FD-4 increased with the increasing concentration of poly-L-Arg. The enhanced absorption was also dependent on the molar concentration, in that the poly-L-Arg with a higher molecular weight increased F(0-9 h) at a lower molar concentration. In addition, for each applied concentration, the poly-L-Arg exhibited a molecular weight-dependence as far as the enhancement of FD-4 absorption was concerned. On the other hand, the maximum absorption rate (MAR) of FD-4, calculated by means of a deconvolution method, tended to reach a maximum plateau level at a lower applied concentration for the poly-L-Arg with the highest molecular weight, but this plateau level was almost the same for poly-L-Arg with molecular weights of 45.5 and 92.0 kDa. Moreover, the simulated absorption profiles of FD-4 indicate that the degree of enhancement (the level of MAR and the subsequent reduction in the absorption rate) was dependent on the molecular weight of poly-L-Arg, while the effect of poly-L-Arg was maintained for a longer period, depending on the applied concentration, although the MAR was relatively similar. These results indicate that the molecular weight of poly-L-Arg appears to affect both the enhancing efficiency (absorption rate) and the time-frame of this enhancing effect, whereas the concentrations of each poly-L-Arg system applied only have an effect on the time-frame. These effects may also be associated with the charge density of a poly-L-Arg molecule.


Assuntos
Dextranos/farmacocinética , Fluoresceína-5-Isotiocianato/farmacocinética , Mucosa Nasal/metabolismo , Peptídeos/farmacologia , Absorção , Animais , Fluoresceína-5-Isotiocianato/análogos & derivados , Masculino , Peso Molecular , Ratos , Ratos Wistar
10.
J Drug Target ; 1(3): 207-15, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8069562

RESUMO

The selective accumulation and tumoricidal effects of cisplatin after intra-arterial infusion suspended in viscous ethyl oleate (VEO) on hepatic cancers of AH 272 tumor-bearing rats and VX-2 tumor-bearing rabbits were compared with those of cisplatin suspensions in ethyl oleate (EO) and Lipiodol Ultra Fluide (LP). The viscosities of VEO, EO and LP were 120, 4, and 21 centipoise (cp) respectively. Complete in vitro release of cisplatin from EO and LP occurred within 24 h, whereas only about 25% of cisplatin was released from VEO over the same period. When EO or VEO containing 3H-oleic acid were infused into the hepatic artery of rat liver inoculated with AH 272 tumor cells, radioactivity in the tumor site was higher than that in normal liver. In the case of cisplatin, concentration ratios after the infusion of EO and VEO were almost the same as those of oily carriers. Similar results were obtained in rabbit liver inoculated with VX-2 tumor cells. Cisplatin concentration in the tumor site seven days after intra-arterial infusion of VEO suspension was 5- and 1.7-fold higher, respectively, than that after EO and LP suspensions. The tumoricidal effect of cisplatin in VEO suspension on AH 272 tumor-bearing rats was higher than that after cisplatin solution and EO and LP suspensions, while VX-2 tumor growth was inhibited by the infusion of all cisplatin-containing oily carriers. VEO suspension thus appears very promising in intra-arterial infusion therapy.


Assuntos
Cisplatino/administração & dosagem , Cisplatino/uso terapêutico , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Animais , Cisplatino/farmacocinética , Infusões Intra-Arteriais , Fígado/química , Fígado/metabolismo , Masculino , Ácidos Oleicos , Platina/farmacocinética , Ratos , Suspensões , Células Tumorais Cultivadas , Viscosidade
11.
Int J Pharm ; 226(1-2): 127-38, 2001 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-11532576

RESUMO

The effect of poly-L-arginine (poly-L-Arg) on the in vivo nasal absorption of FITC-dextrans with a mean molecular weight ranging from 4.3 to 167 kDa and recombinant human granulocyte colony-stimulating factor (rhG-CSF) in rats were studied. When FITC-dextrans were co-administered intranasally with 1.0 w/v% poly-L-Args of different molecular weight (MW, ca. 45.5 and 92 kDa, poly-L-Arg (50) and poly-L-Arg (100)), the bioavailability (F(infinity)) increased markedly compared with that after administration of FITC-dextran alone. However, the F(infinity) decreased exponentially with the increasing molecular weight of FITC-dextrans. There was no significant difference between the enhanced nasal absorption of FITC-dextrans achieved by the co-administration of poly-L-Arg (50) and poly-L-Arg (100). Moreover, the relationship between the F(infinity) and the molecular weight of FITC-dextrans indicated that the molecular weight of protein drugs, which exhibited efficient absorption with poly-L-Arg, was about 20 kDa, when the lower limit of bioavailability for developing a potent transnasal delivery system was assumed to be about 10%. Indeed, the nasal absorption of rhG-CSF, which has a molecular weight of 18.8 kDa, was also increased after co-administration of 1.0 w/v% poly-L-Arg (50) and the F(infinity) was about 11%. It seems likely that poly-L-Arg can be used to provide adequate nasal absorption of various protein drugs which have a molecular weight of about 20 kDa, thereby allowing the successful development of a variety of transnasal drug delivery systems.


Assuntos
Arginina/farmacologia , Dextranos/farmacocinética , Fluoresceína-5-Isotiocianato/farmacocinética , Fator Estimulador de Colônias de Granulócitos/farmacocinética , Cavidade Nasal/metabolismo , Absorção/efeitos dos fármacos , Análise de Variância , Animais , Área Sob a Curva , Dextranos/administração & dosagem , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos , Fluoresceína-5-Isotiocianato/administração & dosagem , Fluoresceína-5-Isotiocianato/análogos & derivados , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Meia-Vida , Peso Molecular , Cavidade Nasal/efeitos dos fármacos , Ratos , Ratos Wistar , Proteínas Recombinantes
12.
Int J Pharm ; 185(1): 1-12, 1999 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-10425360

RESUMO

Several cationic compounds were screened as potential nasal absorption enhancers to increase intranasal absorption of a model drug, fluorescein isothiocyanate labeled dextran (MW 4.4 kDa, FD-4), without nasal membrane damage in rats. Their effects were compared with those of classical enhancers. Various cationic compounds (poly-L-arginines with different molecular weights (MW 8.9, 45.5 and 92.0 kDa, poly-L-Arg (10), (50) and (100), respectively), L-arginine (L-Arg), L-lysine (L-Lys), and cetylpyridinium chloride (CPCL) were evaluated. Of the cationic compounds, poly-L-Arg and CPCL greatly enhanced the intranasal absorption of FD-4, as did chitosan, a cationic polysaccharide which has been reported to show a great effect on the transnasal delivery of peptide and protein drugs. The enhancing intensity by poly-L-Arg was dependent on its molecular weight. Rank order of the enhancing ratio, calculated from the AUC ratio for the enhancer treatment against the untreatment, was 0.5% poly-L-Arg (100) congruent with0.5% sodium dodecylsulfate congruent with0.5% CPCL?0.5% poly-L-Arg (50)?0.5% sodium deoxycholate congruent with0.5% sodium taurodihydrofusidate?0.5% polyoxyethylene-9-lauryl ether congruent with0.5% lysophosphatidylcholine?0.5% chitosan congruent with0.5% poly-L-Arg (10)>/=10% L-Arg congruent with10% L-Lys?0.5% sodium glycocholate congruent with0.5% sodium taurocholate congruent with0.5% EDTA. Only the poly-L-Args represented almost the same degree of hemolysis of cationic compounds compared with pH 7.0 phosphate buffered saline in the rat erythrocyte lysis experiment. The enhancing ratio by classical enhancers correlated with leaching of protein, phospholipids and LDH from isolated rabbit nasal mucosa. CPCL also fell on the regression lines between the enhancing ratio and their degree of leaching from classical enhancers. In contrast, the enhancing intensities by poly-L-Arg (10), (50) and (100) were greatly shifted from the regression line: the amount of leaching was markedly low in spite of a great enhancement of FD-4 absorption. These findings suggest that of the assessed enhancers only the poly-L-Args enhance the transnasal delivery of high molecular substances without severe damage to the nasal mucosal membrane. Poly-L-Arg is therefore a promising candidate having a good balance between enhancing activity and safety for nasal peptide and protein delivery.


Assuntos
Dextranos/farmacocinética , Eritrócitos/efeitos dos fármacos , Fluoresceína-5-Isotiocianato/análogos & derivados , Mucosa Nasal/metabolismo , Tensoativos/farmacologia , Absorção , Administração Intranasal , Animais , Área Sob a Curva , Arginina/farmacologia , Cátions , Cetilpiridínio/farmacologia , Quitina/análogos & derivados , Quitina/farmacologia , Quitosana , Dextranos/administração & dosagem , Sinergismo Farmacológico , Fluoresceína-5-Isotiocianato/administração & dosagem , Fluoresceína-5-Isotiocianato/farmacocinética , Hemólise , Injeções Intravenosas , L-Lactato Desidrogenase/metabolismo , Lisina/farmacologia , Masculino , Mucosa Nasal/efeitos dos fármacos , Peptídeos/farmacologia , Fosfolipídeos/metabolismo , Proteínas/metabolismo , Coelhos , Ratos , Ratos Wistar
13.
Arch Pharm Res ; 17(2): 57-9, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10319131

RESUMO

The effect of sodium taurodihydrofusidate (STDHF) on drug permeation across nasal mucosa was studied in vitro using Ussing type diffusion chamber. Disodium cromoglicate (DSCG, M.W. 512.3) and fluorescein isothiocyanate-dextran (FD) of different molecular weights (M.W. 4400-71200) were used as model drugs. Permeation profiles of DSCG and FDs showed a typical pseudo steady-state curve with short lag time. The permeability coefficient of FD (M.W. 9400) sigmodially increased with increasing STDHF concentration. It also enhanced the DSCG permeation. Interestingly the enhancement efficacy was independent of molecular weight of penetrants.


Assuntos
Adjuvantes Farmacêuticos , Ácido Fusídico/análogos & derivados , Mucosa Nasal/metabolismo , Administração Intranasal , Animais , Antiasmáticos/farmacocinética , Cromolina Sódica/farmacocinética , Dextranos/química , Dextranos/farmacocinética , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Fluoresceína-5-Isotiocianato/farmacocinética , Técnicas In Vitro , Masculino , Peso Molecular , Coelhos
14.
Yao Xue Xue Bao ; 36(2): 140-4, 2001 Feb.
Artigo em Zh | MEDLINE | ID: mdl-12579884

RESUMO

AIM: To investigate the effect of particle size and high speed flow of helium gas on the systemic absorption of indomethacin using a needle-less injection system. METHODS: Poly-L-lactic acid microspheres containing indomethacin was prepared by the o/w solvent evaporation technique. After anesthetizing the male hairless rat, microspheres filled in the tube cartridge was accelerated by a stream of helium gas at various velocity in the Helios gun system, and then was introduced to the abdominal skin. RESULTS: Introduction of indomethacin to the hairless rat skin was proportionally increased with enhancing the helium pressure (supersonic flow). Bioavailability and Cmax were also dependent on the helium pressure. CONCLUSION: This method can be used to deliver the powered drug and/or microparticulate systems into the skin tissues and the systemic circulation.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Indometacina/administração & dosagem , Indometacina/farmacocinética , Administração Cutânea , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Disponibilidade Biológica , Hélio , Ácido Láctico , Masculino , Microesferas , Poliésteres , Polímeros , Ratos , Absorção Cutânea
15.
Yao Xue Xue Bao ; 36(7): 535-8, 2001 Jul.
Artigo em Zh | MEDLINE | ID: mdl-12585088

RESUMO

AIM: To improve the bioavailability and taste of fast-disintegrating tablet (FD tablet) containing nicorandil-loaded particles. METHODS: A FD tablet containing nicorandil-loaded particles with 1%-4% croscarmellose sodium in addition of D-mannitol and lactose (9:1) was prepared and the dissolution and absorption characteristics were examined, in comparison with FD tablet and commercial tablets of nicorandil. In vivo absorption of nicorandil from FD tablet was evaluated in beagle dogs. RESULTS: The disintegration time of FD tablets containing 1% croscarmellose sodium with 6 mm and 10 mm in diameter were about 12 and 23 seconds, respectively. When nicorandil-loaded particles consist of myristyl alcohol and stearyl alcohol were put in FD tablet, nicorandil release from FD tablet continued until 6 h while nicorandil release from Sigmart and FD tablet containing nicorandil crystals finished within 5 min. In vivo absorption of nicorandil from Sigmart and FD tablet containing nicorandil crystals was very similar after oral administration in beagle dogs and no statistic difference in AUC, Tmax, Cmax was observed between these tablets. However pharmacokinetics parameters of nicorandil after oral administration of FD tablet containing nicorandil-loaded particles showed that nicorandil was delivered into the body at a suitable absorption rate with similar AUC, delayed Tmax and lower Cmax. CONCLUSION: The reports suggest that the modification of properties of myristyl alcohol and stearyl alcohol released from the drug-loaded particles system would lead to more acceptable bioavailability of the system. However, The formulation of particles and may have a masking effect against the bitter taste and irritation of the drug.


Assuntos
Antiarrítmicos/administração & dosagem , Nicorandil/administração & dosagem , Administração Oral , Animais , Antiarrítmicos/farmacocinética , Disponibilidade Biológica , Carboximetilcelulose Sódica , Química Farmacêutica , Cães , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Lactose/química , Masculino , Manitol/química , Nicorandil/farmacocinética , Solubilidade , Comprimidos/administração & dosagem , Comprimidos/farmacocinética , Tecnologia Farmacêutica
16.
Jpn J Antibiot ; 36(12): 3343-8, 1983 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-6674546

RESUMO

Cefbuperazone, a new cephamycin antibiotic, was used in 13 complicated UTI cases. The drug was given at a dose of 1 g in 100 ml of physiological saline solution twice a day for 5 - 14 days and judged for its clinical effect in 11 cases on days 5 - 7 according to the criteria of the UTI committee. Overall clinical efficacy was excellent in 3 cases, moderate in 2 cases and poor in 6 cases, the effectiveness rate was 45.5%. In laboratory findings, slightly elevated transaminase and A1-P were observed in 2 cases and 1 case, respectively.


Assuntos
Cefamicinas/uso terapêutico , Infecções Urinárias/tratamento farmacológico , Adulto , Idoso , Cefamicinas/administração & dosagem , Cefamicinas/efeitos adversos , Avaliação de Medicamentos , Feminino , Humanos , Infusões Parenterais , Masculino , Pessoa de Meia-Idade
17.
Hinyokika Kiyo ; 31(3): 441-8, 1985 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-4025080

RESUMO

Seventy out-patients suffering from chronic bacterial prostatitis were treated with a combination of trimethoprim plus rifampicin or trimethoprim alone. A combination of 300 mg. rifampicin plus 160 mg. trimethoprim (rifaprim) was used. Forty-four patients were administered rifaprim at doses of 920 mg. (twice a day) for two months. Twenty-six patients were administered trimethoprim at doses of 320 mg. (twice a day) for two months. Cultures of the expressed prostatic secretions (EPS) yielded gram-positive bacteria in 61 patients and gram-negative bacteria in 9. In rifaprim group, clinical responses were excellent in 9 cases, moderate in 23 cases and poor in 12 cases. The efficacy rate was 73%. In trimethoprim group, excellent in 1 case, moderate in 14 cases and poor in 11 cases. The efficacy rate was 60%. Seven patients of chronic bacterial prostatitis were treated by local injection of tobramycin into the prostate. The antibiotic level in the prostatic fluid twenty-four hours after injection was very high. The pain and discomfort experienced by the patients during injection into the prostate were minimal. Local necrosis was not found after histologic or electron microscopic studies of biopsied prostatic specimen after the injection. Results show that this simple method should be valuable in the treatment of the refractory group of chronic bacterial prostatitis.


Assuntos
Infecções Bacterianas/tratamento farmacológico , Prostatite/tratamento farmacológico , Rifampina/administração & dosagem , Trimetoprima/administração & dosagem , Adulto , Doença Crônica , Combinação de Medicamentos , Avaliação de Medicamentos , Quimioterapia Combinada , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Próstata/ultraestrutura , Tobramicina/administração & dosagem
18.
Hinyokika Kiyo ; 33(7): 1017-20, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3687624

RESUMO

A study of 75 patients undergoing transurethral surgery with relatively short-term urethral catheterization with a sterile closed gravity drainage system revealed a 72% over-all incidence of negative urine cultures after catheter removal. The combination of prophylactic use of antimicrobials and a standardized catheter care system is valuable for preventing catheter-associated bacteriuria.


Assuntos
Prostatectomia , Bexiga Urinária/cirurgia , Cateterismo Urinário/efeitos adversos , Infecções Urinárias/etiologia , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Bacteriúria/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pré-Medicação , Neoplasias da Bexiga Urinária/cirurgia , Infecções Urinárias/prevenção & controle
19.
Hinyokika Kiyo ; 33(8): 1256-60, 1987 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-3425523

RESUMO

A forty-two-year-old man was seen with right lumbar pain. Physical examination revealed a right flank mass. Conventional excretory urography showed lack of right renal function, whereas left kidney was visualized. Right nephrectomy was performed. A cluster of several different sized cysts was disclosed in the right renal region. The renal surface was smooth. The removed kidney weighed 1,150 g. The ureter was completely obstructed at the ureteropelvic junction. Cysts were filled with matrix calculi. Pathological examination showed dysplastic glomeruli and primitive tubules within loose embryonic mesenchyme between two cysts whose walls consisted of smooth muscle strands and connective tissue. The final diagnosis was a congenital unilateral multicystic kidney with renal matrix calculi. The multicystic kidney is the most common form of renal cystic disease in infancy. However, few cases in adults have been reported. The diagnostic approach, treatment and outcome of a congenital unilateral multicystic kidney are discussed.


Assuntos
Cálculos Renais/complicações , Doenças Renais Policísticas/congênito , Adulto , Humanos , Cálculos Renais/patologia , Masculino , Doenças Renais Policísticas/complicações , Doenças Renais Policísticas/patologia
20.
Hinyokika Kiyo ; 32(8): 1141-3, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3788739

RESUMO

Enterovesical fistula as a complication of Crohn's disease is a rare condition. A case of Crohn's disease with ileovesical and rectovesical fistulas manifesting as bladder tumor is presented.


Assuntos
Doença de Crohn/complicações , Doenças do Íleo/diagnóstico , Fístula Intestinal/diagnóstico , Fístula da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/diagnóstico , Adulto , Diagnóstico Diferencial , Humanos , Doenças do Íleo/etiologia , Fístula Intestinal/etiologia , Masculino , Fístula da Bexiga Urinária/etiologia
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