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1.
Microsc Microanal ; 29(Supplement_1): 499-500, 2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37613095
2.
J Dent Res ; 94(4): 594-601, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25535203

RESUMO

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is likely to be caused by continuous imperfection of bone healing after surgical treatments in patients with long-term administration of nitrogen-containing bisphosphonates (NBPs). NBPs inhibit osteoclastic bone resorption by impairing the mevalonic acid sterol pathway in osteoclasts. Thus, we hypothesized that exogenous mevalonic acid metabolites restore the inhibitory effects of NBPs on osteoclastogenesis and bone remodeling. To clarify the effects of mevalonic acid metabolites, especially geranylgeranyl pyrophosphate (GGPP) and geranylgeranyl transferase substrate geranylgeranyl acid (GGOH), we examined the effects of zoledronic acid with or without GGOH or GGPP on osteoclast differentiation, multinucleation, and bone mineral deposition in tooth-extracted sockets. Zoledronic acid decreased the number of tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells derived from mouse osteoclast precursors treated with receptor activator of nuclear factor-κB ligand and macrophage colony-stimulating factor. Zoledronic acid simultaneously suppressed not only the expressions of osteoclastic differentiation-related molecules such as TRAP, cathepsin K, calcitonin receptor, and vacuolar H-ATPase but also those of multinucleation-related molecules such as dendrocyte-expressed 7 transmembrane proteins and osteoclast stimulatory transmembrane protein. Treatment with GGOH or GGPP, but not farnesyl acid, restored the zoledronic acid-inhibited number of TRAP-positive multinuclear cells together with the expressions of these molecules. Although intraperitoneal administration of zoledronic acid and lipopolysaccharide into mice appeared to induce BRONJ-like lesions with empty bone lacunae and decreased mineral deposition in tooth-extracted socket, both GGOH and GGPP partially restored the inhibitory effects on zoledronic acid-related mineral deposition. These results suggest the potential of mevalonic acid metabolites as therapeutic agents for BRONJ.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Difosfonatos/farmacologia , Imidazóis/farmacologia , Ácido Mevalônico/farmacologia , Osteoclastos/efeitos dos fármacos , Fosfatase Ácida/análise , Proteínas Adaptadoras de Transdução de Sinal/efeitos dos fármacos , Animais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Remodelação Óssea/efeitos dos fármacos , Calcificação Fisiológica/efeitos dos fármacos , Catepsina K/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Diterpenos/farmacologia , Farneseno Álcool/farmacologia , Isoenzimas/análise , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Masculino , Maxila/efeitos dos fármacos , Proteínas de Membrana/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Fosfatos de Poli-Isoprenil/farmacologia , Receptores da Calcitonina/efeitos dos fármacos , Salmonella , Fosfatase Ácida Resistente a Tartarato , Alvéolo Dental/efeitos dos fármacos , ATPases Vacuolares Próton-Translocadoras/efeitos dos fármacos , Ácido Zoledrônico
3.
Int J Immunopathol Pharmacol ; 22(3): 707-14, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19822087

RESUMO

Thalidomide is an effective drug for chronic inflammatory diseases, but the mechanism underlying its immunomodulatory action remains uncertain. Thalidomide has been reported to clinically improve chronic inflammatory granulomatous disorders. In such disorders, the granulomas consist of epithelioid cells, scattered lymphocytes and multinucleated giant cells (MNGC; Langhans-type cells). The present experimental approach permitted the reproduction of MNGC formation from peripheral blood monocytes and examination of thalidomides effect on it. MNGC can be effectively generated from monocytes cultured in the presence of interleukin-4 (IL-4) and macrophage colony-stimulating factor(M-CSF) for 14 days. Thalidomide can inhibit the formation of MNGC in a dose-dependent manner. MNGC formation was partly inhibited by the presence of neutralizing TNF-alpha antibody in the responses induced by IL-4 and M-CSF. Autocrinal TNF-alpha production and modulation of cadhelin expression to regulate cell adhesion might be involved in this inhibitory action of thalidomide. Our results support thalidomides clinical efficacy in the treatment of chronic granulomatous disorders (granulomatosis).


Assuntos
Anti-Inflamatórios/farmacologia , Transdiferenciação Celular/efeitos dos fármacos , Células Gigantes de Langhans/efeitos dos fármacos , Granuloma/tratamento farmacológico , Monócitos/efeitos dos fármacos , Talidomida/farmacologia , Anticorpos , Comunicação Autócrina/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Células Gigantes de Langhans/imunologia , Células Gigantes de Langhans/patologia , Granuloma/imunologia , Granuloma/patologia , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-4/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Monócitos/imunologia , Monócitos/patologia , Interferência de RNA , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
5.
J Appl Microbiol ; 105(5): 1461-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18795977

RESUMO

AIMS: To measure antibacterial activity of the semi-synthetic flavonoid 3-O-octanoyl-(-)-epicatechin and investigate the mechanism of action. METHODS AND RESULTS: MICs determined by the broth microdilution method were 50 microg ml(-1) for beta-lactam sensitive and resistant Staphylococcus aureus, and 100 microg ml(-1) for vancomycin sensitive and resistant enterococci. In time-kill studies, 100 microg ml(-1) 3-O-octanoyl-(-)-epicatechin reduced colony forming unit numbers of antibiotic sensitive and methicillin-resistant Staph. aureus below detectable levels within 120 min. Bacterial aggregation was not observed when cells exposed to 3-O-octanoyl-(-)-epicatechin were examined by light microscopy. It was also shown that 50 microg ml(-1) 3-O-octanoyl-(-)-epicatechin is capable of reducing colony forming unit numbers of high cell density Staph. aureus populations by 80-fold within 60 min incubation, and inducing leakage of 50% of their internal potassium within just 10 min. CONCLUSIONS: 3-O-Octanoyl-(-)-epicatechin is active against Gram-positive bacteria, has bactericidal activity against both antibiotic sensitive and resistant strains, and is likely to exert its primary antibacterial effect by damaging the cytoplasmic membrane. SIGNIFICANCE AND IMPACT OF THE STUDY: 3-O-Octanoyl-(-)-epicatechin has significant antibacterial activity and additional structural modification and/or formulation studies may allow this to be potentiated.


Assuntos
Antibacterianos/farmacologia , Catequina/análogos & derivados , Enterococcus/efeitos dos fármacos , Flavonoides/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Catequina/farmacologia , Agregação Celular/efeitos dos fármacos , Farmacorresistência Bacteriana/fisiologia , Enterococcus/citologia , Testes de Sensibilidade Microbiana , Staphylococcus aureus/citologia
6.
Eur J Med Chem ; 41(6): 697-708, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16584813

RESUMO

New series histone deacetylase inhibitors comprising a hydroxamic acid or 2-aminobenzamide group as a zinc-chelating function were synthesized and evaluated for antiproliferative activities against a panel of human cancer cells. The 2-aminobenzamide series inhibitors generally had the potency in cell growth inhibitions comparable to that of MS-275. Among them, the compound having a (3,4-difluorobenzyl)(2-hydroxyethyl)amino group at one end and a 2-aminobenzamide group at the other of molecule showed the most promising profile as an anticancer drug candidate, since it had a comparatively low toxicity as did MS-275 against a normal fibroblast cell CCD-1059SK. Additionally, the derivative exhibited a high recovery in human plasma stability test.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/farmacologia , ortoaminobenzoatos/síntese química , ortoaminobenzoatos/farmacologia , Antineoplásicos/sangue , Inibidores Enzimáticos/sangue , Humanos , Ácidos Hidroxâmicos/sangue , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Espectrofotometria Infravermelho , ortoaminobenzoatos/sangue
7.
J Dairy Sci ; 86(10): 3362-5, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14594256

RESUMO

The ovine major histocompatibilty complex (Ovar) class II DRB1 second exon was amplified by polymerase chain reaction (PCR) from DNA samples of 52 Suffolk sheep. Polymerase chain reaction products were characterized by the restriction fragment length polymorphism (RFLP) technique using nine restriction enzymes, RsaI, HaeIII, SacI, SacII, DdeI, NciI, Hin1I, EcoRI, and BstNI, yielding 13 types. Sequencing of cloned PCR products identified 16 Ovar-DRB1 alleles. Collectively, all PCR-RFLP patterns exactly matched those predicted from DNA sequences. These findings strongly indicate that the PCR-RFLP method using a combination of nine restriction endonucleases is a very powerful tool in Ovar typing.


Assuntos
DNA/análise , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Ovinos/imunologia , Alelos , Animais , DNA/química , Enzimas de Restrição do DNA/metabolismo , Genótipo , Dados de Sequência Molecular , Ovinos/genética
8.
Eur J Immunogenet ; 30(4): 275-82, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12919289

RESUMO

To investigate the genetic diversity of the sheep MHC (Ovar) class II DRB1 locus, we amplified exon 2 of Ovar-DRB1 alleles by polymerase chain reaction (PCR) and determined the nucleotide sequences of both resultant strands after cloning. In our study of a total of 97 sheep of three breeds, namely, Suffolk, Cheviot and Corriedale, we identified 18 previously published alleles and 17 new alleles. These alleles were 83.4 to 94.1% identical at the nucleotide level and 71.4 to 90.9% identical at the amino acid level to Ovar-DRB1*0101. We identified six new alleles in Cheviot sheep and 11 new alleles in Suffolk sheep. Furthermore, we identified 15, 6 and 1 allele in Suffolk, Cheviot and Corriedale sheep, respectively, that have only been found in these breeds to date. Analysis of the frequencies of the various Ovar-DRB1 alleles in each breed indicated that Ovar-DRB1*0702 was the most frequent allele in Suffolk sheep (23.9%), Ovar-DRB1*0203 was the most frequent allele in Cheviot sheep (27.5%) and Ovar-DRB1*0201 was the most frequent allele in Corriedale sheep (25.0%). A comparative analysis of the positions of polymorphic residues in the first extracellular domain of the DRB genes of sheep, humans and mice revealed an extraordinary similarity amongst the positions of polymorphic residues that are associated with the antigen recognition site (ARS). Moreover, the extent of polymorphism seems to be similar in sheep, humans and mice.


Assuntos
Variação Genética , Antígenos de Histocompatibilidade Classe II/genética , Ovinos/genética , Sequência de Aminoácidos , Animais , Humanos , Camundongos , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Alinhamento de Sequência
11.
Ann Hematol ; 81(5): 285-8, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12029539

RESUMO

We report here an autopsy case of true malignant histiocytosis. The patient was a 67-year-old woman who exhibited fever, wasting, hepatosplenomegaly, and progressive pancytopenia. The bone marrow aspiration disclosed hemophagocytosing cells, which resembled histiocytes. The molecular analysis did not show the clonal gene rearrangement of T-cell receptor or immunoglobulin heavy chain. Although the patient had been started on methylprednisolone pulse therapy and chemotherapy with etoposide, she died from cerebral hemorrhage. The autopsy specimens of spleen and liver showed extensive infiltration of atypical cells, for which histiocytic origin was identified with an immunohistochemical method using monoclonal antibodies against CD11c, CD68, macrophage colony-stimulating factor (M-CSF), M-CSF receptor, lysozyme, antitrypsin and alpha1-antichymotrypsin. Recent investigations have disclosed that in most cases diagnosed as malignant histiocytosis, hemophagocytosis was reactive and not evoked by histiocytic malignancy. True malignant histiocytosis, for which histiocytic origin is confirmed, is extremely rare.


Assuntos
Análise Citogenética , Sarcoma Histiocítico/patologia , Imuno-Histoquímica/métodos , Idoso , Anticorpos Monoclonais , Medula Óssea/patologia , Linhagem Celular , Evolução Fatal , Feminino , Humanos , Fígado/patologia , Baço/patologia
12.
Yakugaku Zasshi ; 121(11): 771-9, 2001 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-11725545

RESUMO

We have been engaged in the development of asymmetric conjugate addition reactions of lithium thiolates, organolithiums and organocopper reagents under the control of external chiral ligands and we have also developed an efficient asymmetric Horner-Wadsworth-Emmons (HWE) reaction using an external chiral Ligand. We attempted to synthesize axial chiral allenes by combination of these conjugate addition reaction and HWE reaction. In the course of this study, we found that Michael-aldol reaction of alkenylphosphonates 1 using LDA and aldehydes results in the direct formation of alpha,beta-unsaturated hydroxyphosphonate 4, which was efficiently converted to allene by treatment with KH or KH-18-crown-6. Furthermore, allenes were synthesized by sequential double HWE reaction in one-flask manner starting from methylenebisphosphonate 8. The key to success is a metal exchange of intermediate lithium alkoxide 4-Li to potassium alkoxide 4-K by the addition of t-BuOK. As our continuous study of carbon-carbon bond formation based on alkenylphosphonates, a cyclization reaction of bisalkenylphosphonate 6 was developed. Although the treatment of 6 with organolithium reagents afforded a mixture of addition-cyclization product 9 and deprotonation-cyclization product 10, the treatment of 6 with LDA gave 10 selectively. These cyclization methods were applied to the synthesis of efficient chiral phosphine ligands.


Assuntos
Carbono/química , Compostos Organofosforados , Alcadienos/síntese química , Química Orgânica , Ciclização , Ligantes , Fenômenos de Química Orgânica , Estereoisomerismo
13.
Nihon Jinzo Gakkai Shi ; 43(7): 589-94, 2001 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-11725556

RESUMO

Nutritional status is one of the most important factors affecting mortality and morbidity in chronic dialysis patients. There are, however, few data on serial body composition changes in these patients. To investigate serial changes in body composition in patients on peritoneal dialysis, we measured intracellular fluid volume(ICF), extracellular fluid volume(ECF), body protein volume(BPV), body fat volume(BFV) and bone mineral content(BMC) using multifrequency bioelectrical impedance analysis (MF-BIA). MF-BIA was performed in 35 patients, consisting of 21 men and 14 women with a mean age of 51.3 +/- 10.9 years, before and after one year of observation. At the baseline in male patients, ICF was 37.0 +/- 3.4%, ECF 19.7 +/- 1.6%, BPV 20.7 +/- 1.7%, BFV 18.1 +/- 6.6% and BMC 4.5 +/- 0.4% of body weight, and in female patients ICF was 34.4 +/- 2.6%, ECF 17.8 +/- 1.9% BPV 19.0 +/- 1.6%, BFV 24.4 +/- 6.2% and BMC 4.5 +/- 0.4% of body weight. In the group of patients whose body weight increased more than 3 kilograms(n = 9), the increase rate of BFV was 32.3 +/- 20.2%, significantly higher than that of the other segments(p < 0.001). On the other hand, in the group of patients whose body weight decreased more than 3 kilograms(n = 5), each segment showed the same extent of decrease and there was no significant difference in the decrease rates among each segment. In the group of patients whose body weight was stable(n = 21), changes in each body composition segment were extremely small. It could be concluded that the body weight increase is due mainly to increase in BFV and body weight decrease results from a concurrent decrease in each body composition segment in peritoneal dialysis patients.


Assuntos
Composição Corporal , Falência Renal Crônica/fisiopatologia , Diálise Peritoneal/efeitos adversos , Adulto , Peso Corporal , Impedância Elétrica , Feminino , Humanos , Falência Renal Crônica/metabolismo , Masculino , Pessoa de Meia-Idade , Estado Nutricional
14.
J Org Chem ; 66(24): 8199-203, 2001 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-11722225

RESUMO

(-)-Neplanocin A (1), S-adenosylhomocystein hydrolase inhibitor, was synthesized. The characteristic of this synthesis is a stereoselective construction of five-membered ring of neplanocin A by intramolecular aldol reaction of the lithium enolate that was generated by conjugate addition of lithium thiolate. TBS-protected chiral omega-oxo-alpha,beta-unsaturated ester 16, which was prepared from D-mannitol, was treated with 1.2 equiv of lithium benzylthiolate in THF at -20 degrees C to give three separable cyclization products in good yields and stereoselectivity. After conversions of protective groups, the benzylsulfanyl part of 21 was removed by oxidation to sulfoxide and subsequent thermal elimination to give the requisite double bond. Through the functional group transformations of 30, total synthesis of (-)-neplanocin A (1) was accomplished.


Assuntos
Adenosina/síntese química , Inibidores Enzimáticos/síntese química , Adenosina/análogos & derivados , Adenosil-Homocisteinase , Antibióticos Antineoplásicos/síntese química , Ciclização , Hidrolases/antagonistas & inibidores , Compostos de Lítio/química , Manitol/química , Mesilatos/química
16.
J Org Chem ; 66(21): 7051-4, 2001 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-11597228

RESUMO

A reaction mode of imines derived from naphthalene-1-carbaldehyde and acyclic alpha,beta-unsaturated aldehydes with organolitium reagents was dependent on the characteristic nature of a substituent on the imine nitrogen atom. An imine having an electron-withdrawing aryl group on the nitrogen atom behaves as a 1,2-directing imine toward organolithium reagents. In contrast, an imine bearing an alkyl or a bulky aryl group favors 1,4-addition of organolithium reagents. Electronic and steric tuning of a substituent on the imine nitrogen atom for a reaction mode was rationalized on the basis of molecular orbital calculations.

17.
Okajimas Folia Anat Jpn ; 78(1): 17-21, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11552286

RESUMO

After preparing the frontal section including the origin of the left portal trunk at the hilar region, the left anatomical lobes of 111 human livers were dissected to reveal the segmental configuration based on the supplying portal vein branches. S2 was consistently located dorsal to S3. However, in contrast to the description in common textbooks for medical students, 19.8% of the specimens carried a paradoxical segmental configuration showing a "caudal and/or rightward" S2 in combination with a "cranial and/or leftward" S3 in the frontal section through the ventral part of the hilar region. The caudal and rightward cases were associated with a specific arrangement of S2 and S3 segmental stems in which the S3 stem ran relatively upward to spread over S2 or both stems ran almost horizontal, respectively. In routine diagnostic radiology, identification of S2 and S3 might sometimes be biased by the generally accepted notion that S2 should be located at the dorsal, cranial and left side of S3.


Assuntos
Fígado/anatomia & histologia , Fígado/irrigação sanguínea , Veia Porta/anatomia & histologia , Humanos
18.
Kaibogaku Zasshi ; 76(2): 223-32, 2001 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-11398354

RESUMO

After preparing threparing the frontal section including the origin of the left portal trunk at the hepatic hilum, 60 human livers (35, entirely; 25, partly) were dissected to reveal segmental configuration and the supplying portal vein branches. We usually observed two combinations of segments, i.e., S2, 4, 5 and 8 or S2, 3, 4, 5 and 8, in the frontal section including the origin of the left portal trunk. However, S8 was sometimes absent in the section when S4 extended to the right and/or upper side. S2 was consistently located dorsal to S3 despite the fact that 11.7% of the specimens carried an unexpected configuration showing a "lower" S2 in combined with an "upper" S3 in the frontal section. The latter case was associated with specific S2 and S3 segmental branches maintaining horizontal courses along a common plane. S4, S5 and S8 were usually arranged from the ventral to the dorsal aspect in this order. Four types of ventral short branches originated at or near the primary portal divisions and supplied the hilar parenchyme adjacent to S4 and/or the anterior segment (S5 or S8). These ventral short branches tended to be associated with the variations of the primary division. Dissection of the liver after frontal section provided a better understanding of the segmental configuration rather than an approach from the hepatic hilum.


Assuntos
Fígado/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Clin Nephrol ; 55(2): 143-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11269678

RESUMO

AIM: Cyclosporin A (CsA) in combination with corticosteroids can be used effectively in steroid-sensitive nephrotic syndrome. However, reports documenting the effectiveness ofCsA monotherapy against such a condition have been scarce. In 11 adults with minimal-change nephrotic syndrome, we have tried very low-dose CsA in the hope of inducing remission without using either corticosteroid or any other immunosuppressive drugs. PATIENTS AND METHODS: Indications for treatment included steroid-sensitive relapsing nephrotic syndrome (7 patients) and first-episode nephrotic syndrome (4 patients). In all patients, corticosteroid and cytotoxic agents had not been given before entry. CsA was administered orally at an initial dose of 2.4 (range 1.5 - 3.1) mg/kg per day. RESULTS: Analysis of the clinical course revealed that 8 of 11 patients entered complete remission after a mean duration of 44 +/- 31 days, whereas 3 patients failed to enter remission to CsA alone, resulting in complete remission combined with methylprednisolone pulse therapy without conventional oral prednisolone. CsA dosages and trough levels between responders and non-responders were similar. Non-responders had much higher levels of serum total cholesterol and higher daily urinary excretion of protein than those of responders, respectively. No patients had significant decrease in creatinine clearance, development of hypertension or suffered from other CsA associated serious side-effects. CONCLUSION: The present data suggest that CsA monotherapy at a very low dose could induce complete remission in adult patients with minimal-change nephrotic syndrome. Conversely, severe hypercholesterolemia would be likely to inhibit the action of CsA against nephrotic conditions.


Assuntos
Ciclosporina/uso terapêutico , Imunossupressores/uso terapêutico , Síndrome Nefrótica/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Hipercolesterolemia/complicações , Japão , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Indução de Remissão , Estatísticas não Paramétricas , Resultado do Tratamento
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