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1.
Mater Sci Eng C Mater Biol Appl ; 62: 662-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26952470

RESUMO

Bioactive surface modification of Ti-29Nb-13Ta-4.6Zr alloy (TNTZ) was performed through three different alkali solution treatments, including the electrochemical (E), hydrothermal (H), and hydrothermal-electrochemical (HE) processes; all of the processes lead to the formation of sodium-contained amorphous titanium oxide layers on TNTZ samples. The TNTZ samples subjected to the E, H, and HE processes exhibit a flat surface, smooth and fine mesh-like structure surface, and rough mesh-like structure surface, respectively. In the bioactive test, namely, simulated body fluid test, apatite inductivity increases as the surface morphology becomes rough. The order of inductivity for the three processes was HE>H>E. The surface chemical composition also affects the apatite induction ability. The surface with fewer niobium species exhibits better apatite inductivity.


Assuntos
Nióbio/química , Tantálio/química , Titânio/química , Zircônio/química , Apatitas/química , Materiais Biocompatíveis/química , Concentração de Íons de Hidrogênio , Teste de Materiais , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Análise Espectral Raman , Propriedades de Superfície , Difração de Raios X
2.
J Mech Behav Biomed Mater ; 61: 174-181, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26866453

RESUMO

Bioactive oxide layers were fabricated on Ti-29Nb-13Ta-4.6Zr alloy (TNTZ) by three different alkali solution treatments: hydrothermal (H), electrochemical (E), and hydrothermal-electrochemical (HE). The adhesive strength of the oxide layer to the TNTZ substrate was measured to determine whether this process achieves sufficient adhesive strength for implant materials. Samples subjected to the HE process, in which a current of 15mA/cm(2) was applied at 90°C for 1h (HE90-1h), exhibited a comparatively higher adhesive strength of approximately 18MPa while still maintaining a sufficiently high bioactivity. Based on these results, an oxide layer fabricated on TNTZ by HE90-1h is considered appropriate for practical biomaterial application, though thicker oxide layers with many cracks can lead to a reduced adhesive strength.


Assuntos
Álcalis/química , Ligas Dentárias , Óxidos/química , Adesivos , Teste de Materiais , Nióbio , Propriedades de Superfície , Tantálio , Resistência à Tração , Titânio , Zircônio
3.
Scand J Immunol ; 83(2): 109-18, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26524607

RESUMO

The incidence of non-alcoholic steatohepatitis (NASH) is increasing. Because gut microbiota have been highlighted as one of the key factors in the pathogenesis of metabolic syndrome, we investigated the involvement of the bacterial component in the progression of non-alcoholic fatty liver (NAFL) to NASH. C57BL/6 mice were fed with maintenance food (MF, groups A and B) or a high caloric diet (HCD, groups C and D) for 1 month. Mice were then divided into four groups: Groups A and C were inoculated with PBS, while groups B and D were inoculated with lipopolysaccharide (LPS) plus complete Freund's adjuvant (CFA). The inoculations were performed a total of 3 times over 3 months. At 6 months, while hepatic steatosis was observed in groups C and D, cellular infiltration and fibrosis were less evident in group C than in group D. Inflammatory cytokines were upregulated in groups B and D. 16S rRNA pyrosequencing of whole colon homogenates containing faeces showed that certain bacterial groups, such as Bacteroidaceae, Peptostreptococcaceae and Erysipelotrichaceae, were increased in groups C and D. Although loading of bacterial components (LPS) resulted in hepatic inflammation in both MF- and HCD-fed mice, HCD feeding was more crucial in the progression of NAFL during the triggering phase.


Assuntos
Lipopolissacarídeos/toxicidade , Hepatopatia Gordurosa não Alcoólica/etiologia , Animais , Colo/imunologia , Colo/microbiologia , Colo/patologia , Citocinas/genética , Dieta/efeitos adversos , Modelos Animais de Doenças , Progressão da Doença , Ingestão de Energia , Microbioma Gastrointestinal/genética , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/microbiologia , Hepatopatia Gordurosa não Alcoólica/patologia , RNA Bacteriano/genética , RNA Bacteriano/isolamento & purificação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação
4.
Med Phys ; 39(6Part6): 3658, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28517569

RESUMO

PURPOSE: We developed a novel automated estimation method for patient setup errors based on simulated and real portal images for prostate cancer radiotherapy. METHODS: The estimation of patient setup errors in this study was based on a template matching technique with a cross-correlation coefficient and Sobel filter between the real portal image and localized pelvic template of reference image, which were DRR (digitally reconstructed radiography) images and simulated portal images. The simulated portal image was derived by projecting a CT image according to an inverse exponential power law of x-ray attenuation for a water-equivalent path length of each voxel of the CT image on each ray from a source to each pixel on the EPID (electric portal imaging device). A localized pelvic template of each patient in AP (anterior-posterior) or lateral view was automatically extracted from the DRR or simulated portal images by cropping a rectangular region, which was determined by using the mean pelvic template and four anatomical feature points. We applied the proposed method to three prostate cancer cases, and evaluated it using the residual error between the patient setup error obtained by proposed method and the gold standard setup error determined by two radiation oncologists. RESULTS: The average residual errors of the patient setup error for the DRR and simulated portal images were 0.79 and 1.26 mm in the left-right (LR) direction, 3.17 and 2.05 mm in the superior-inferior (SI) direction, 1.69 and 5.82 mm in the anterior-posterior (AP) direction, 3.84 and 6.94 mm in Euclidean distance (ED), respectively. If we used the simulated portal image for LR and SI directions and the DRR image for AP direction, the Euclidean distance was 3.22 mm. CONCLUSIONS: The proposed method has a potential to correctly estimate patient setup errors for prostate cancer radiotherapy.

6.
Lab Anim ; 39(1): 122-9, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15703134

RESUMO

The Matsumoto Eosinophilic Shinshu (MES) rat originated from an inbred mutant colony of rats with spontaneous eosinophilia. As part of an investigation of the pathogenesis of the MES rat, we examined the haematology data for 106 males and 88 females and age-associated changes using an automated haematology analyser, flow cytometric analysis and morphological examination. The data at 10 weeks of age showed the MES rats had higher counts for eosinophils and neutrophils, slightly higher counts for lymphocytes, monocytes, basophils, and large unstained cells (LUCs), and slightly lower values for the erythrocytic parameters when compared with Sprague-Dawley (SD) rats. In data for MES rats aged 8 to 20 weeks, eosinophil counts increased with age up to 20 weeks together with some increased neutrophil counts. After 11 weeks of age, counts for lymphocytes, monocytes, basophils, and LUCs in the MES rats were also slightly increased. In female MES rats, flow cytometric analysis showed increased counts for pan-T+ cells, but blasts, abnormal granulocytes and lymphocytes were not detected morphologically. The MES rat characterized by the haematological findings could be a useful animal model for studies of hypereosinophilia.


Assuntos
Autoanálise/veterinária , Eosinofilia/veterinária , Testes Hematológicos/veterinária , Doenças dos Roedores/sangue , Envelhecimento , Animais , Autoanálise/instrumentação , Modelos Animais de Doenças , Eosinofilia/sangue , Eosinofilia/genética , Contagem de Eritrócitos/veterinária , Índices de Eritrócitos/veterinária , Feminino , Citometria de Fluxo/veterinária , Testes Hematológicos/instrumentação , Hemoglobinas/análise , Contagem de Leucócitos/veterinária , Subpopulações de Linfócitos , Masculino , Ratos , Ratos Endogâmicos , Ratos Mutantes , Ratos Sprague-Dawley , Doenças dos Roedores/genética
7.
Clin Exp Immunol ; 130(1): 156-61, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12296867

RESUMO

The aim of the present study was to evaluate levels of soluble CD 163 in sera and fluids from rheumatoid arthritis (RA) patients and elucidate the mechanism that regulates the shedding of CD163. Levels of soluble CD163 in sera and fluids from RA patients were examined by a sandwich enzyme immunoassay and Western blotting. To determine the effects of tissue inhibitors of metalloproteinase (TIMPs) on the shedding of CD163 from monocytes/macrophages, levels of soluble CD163 in cultures of monocytes/macrophages and the expression of CD163 on monocytes/macrophages in the presence or absence of TIMPs were examined by a sandwich enzyme immunoassay and flow cytometry, respectively. The clinical marker that was most associated with serum levels of soluble CD163 was levels of CRP. TIMP-3, but not TIMP-1 or TIMP-2, inhibited the shedding of CD163 from monocytes/macrophages. It was shown that serum levels of soluble CD163 are a sensitive and reliable marker to monitor activated macrophages in synovitis from RA patients and the results imply that the responsible proteinase for the shedding of CD163 is not a member of the matrix metalloproteinases, but is likely to be a member of ADAMs.


Assuntos
Antígenos CD , Antígenos de Diferenciação Mielomonocítica/análise , Artrite Reumatoide/metabolismo , Doenças Autoimunes/metabolismo , Receptores de Superfície Celular/análise , Inibidor Tecidual de Metaloproteinase-3/antagonistas & inibidores , Adulto , Idoso , Animais , Antígenos de Diferenciação Mielomonocítica/sangue , Biomarcadores , Linhagem Celular/química , Dexametasona/farmacologia , Feminino , Humanos , Macrófagos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Receptores de Superfície Celular/sangue , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia , Solubilidade , Spodoptera , Líquido Sinovial/química , Transfecção
8.
Gynecol Oncol ; 83(3): 555-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11733971

RESUMO

OBJECTIVE: The aim of this study was to determine if the mitotic index (MI) and the Ki-67 nuclear antigen labeling index (Ki67LI) obtained from biopsy specimens could be used as predictors of chemotherapy response in uterine cervical carcinomas. METHODS: Six patients with squamous cell carcinoma who received neoadjuvant chemotherapy before radical surgery were entered into the study. The MI and the Ki67LI were evaluated using hematoxylin and eosin (H&E)-stained and immunostained slides before and after chemotherapy. Tumor size was measured three-dimensionally by magnetic resonance imaging. We compared the values of MI and Ki67LI with changes in tumor size. RESULTS: The cases were classified according to the percentage reduction in tumor mass: one case showed a marked response (98%), four showed a moderate response (53-78%), and one showed a slight response (approximately 0%). In the case with a marked response, the MI values before chemotherapy and 3 and 7 days after chemotherapy were 15, 2, and 0, respectively. The corresponding Ki67LI values were 51, 16, and 0, respectively. In the moderate response cases, the corresponding MI values before and 3 and 7 days after chemotherapy were 3.9-13.6, 0.8-1.6, and 1.6-4.0, respectively. The Ki67LI was 21.8-44.2 before chemotherapy, with two cases increasing and two decreasing at 7 days after chemotherapy. In the case showing a slight response, the MI values before chemotherapy and 3 and 7 days after chemotherapy were 0.5, 0.8, and 1.0, respectively. The Ki67LI was 4.0 before chemotherapy and increased slightly to 6.0 at 7 days after chemotherapy. CONCLUSIONS: In six cases examined, high MI and Ki67LI values before chemotherapy and a marked decrease in MI shortly after chemotherapy appeared to be predictors of good neoadjuvant chemotherapy response in uterine cervical carcinomas.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Antígeno Ki-67/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia , Adulto , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/cirurgia , Divisão Celular/efeitos dos fármacos , Feminino , Humanos , Pessoa de Meia-Idade , Índice Mitótico , Terapia Neoadjuvante , Valor Preditivo dos Testes , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/cirurgia
9.
Circulation ; 104(12): 1407-12, 2001 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-11560857

RESUMO

BACKGROUND: Understanding the precise molecular mechanisms underlying the phenomenon of restenosis after PTCA may help us to develop a new strategy for the treatment of restenosis after PTCA. The purpose of this study was to identify the genes involved in vascular restenosis. METHODS AND RESULTS: Applying a differential hybridization method to a model of the balloon-injured rabbit aorta, we identified 6 cDNA clones that were upregulated after injury. Northern blot showed that 5 genes, but not apolipoprotein J (apoJ)/clusterin, were constitutively expressed in noninjured aorta and upregulated after balloon injury. ApoJ mRNA was not detectable in noninjured aorta (control), began to be expressed at 6 hours after injury, showed a peak level at 24 hours (a 48-fold increase), gradually declined, and returned to the control level at 24 weeks. Western blot and immunohistochemistry demonstrated no expression of apoJ protein in noninjured aorta, an expression of apoJ at 2 days after balloon injury, and a peak level (a 55-fold increase) at 2 to 8 weeks. The expression of apoJ protein continued until 24 weeks after injury. In situ hybridization revealed that apoJ mRNA was expressed in smooth muscle cells (SMCs) of media at 2 days after injury and in SMCs of media and neointima at 2 weeks. To analyze the function of apoJ, stably transfected rabbit SMCs were created. The expression of apoJ stimulated proliferation and migration of SMCs. CONCLUSIONS: ApoJ is dramatically induced in media and neointima after vascular injury, suggesting that apoJ contributes to restenosis after angioplasty.


Assuntos
Aorta/metabolismo , Doenças da Aorta/metabolismo , Glicoproteínas/biossíntese , Glicoproteínas/genética , Chaperonas Moleculares/biossíntese , Chaperonas Moleculares/genética , Músculo Liso Vascular/metabolismo , Angioplastia Coronária com Balão/efeitos adversos , Animais , Aorta/lesões , Aorta/patologia , Doenças da Aorta/etiologia , Doenças da Aorta/patologia , Western Blotting , Divisão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Clusterina , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Glicoproteínas/farmacologia , Imuno-Histoquímica , Hibridização In Situ , Masculino , Chaperonas Moleculares/farmacologia , Dados de Sequência Molecular , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , RNA Mensageiro/biossíntese , Coelhos , Análise de Sequência de DNA
10.
J Neurosci Res ; 65(4): 289-97, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11494364

RESUMO

Huntington's disease (HD) is a neurodegenerative disorder characterized by the expansion of CAG repeats in exon 1 of the HD gene. To clarify the instability of expanded CAG repeats in HD patients, an HD model mouse has been generated by gene replacement with human exon 1 of the HD gene with expansion to 77 CAG repeats. Chimeric proteins composed of human mutated exon 1 and mouse huntingtin are expressed ubiquitously in brain and peripheral tissues. One or two CAG repeat expansion was found in litters from paternal transmission, whereas contraction of CAG repeat in litters was observed through maternal transmission. Elderly mice show greater CAG repeat instability than younger mice, and a unique case was observed of an expanded 97 CAG repeat mouse. Somatic CAG repeat instability is particularly pronounced in the liver, kidney, stomach, and brain but not in the cerebellum of 100-week-old mice. The same results of expanded CAG repeat instability as observed in this HD model mouse were confirmed in the human brain of HD patients. Glial fibrillary acidic protein (GFAP)-positive cells have been found to be increased in the substantia nigra (SN), globus pallidus (GP), and striatum (St) in the brains of 40-week-old affected mice, although without neuronal cell death. The CAG repeat instability and increase in GFAP-positive cells in this mouse model appear to mirror the abnormalities in HD patients. The HD model mouse may therefore have advantages for investigations of molecular mechanisms underlying instability of CAG repeats.


Assuntos
Modelos Animais de Doenças , Doença de Huntington/genética , Camundongos Transgênicos , Expansão das Repetições de Trinucleotídeos , Fatores Etários , Animais , Astrócitos/química , Astrócitos/patologia , Éxons , Expressão Gênica/genética , Proteína Glial Fibrilar Ácida/análise , Gliose/genética , Gliose/patologia , Globo Pálido/patologia , Humanos , Doença de Huntington/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Mosaicismo , Neostriado/patologia , Substância Negra/patologia
11.
Planta Med ; 67(4): 331-4, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11458449

RESUMO

We examined the effects of various flavonoids isolated from the roots of Scutellaria baicalensis Georgi on adhesion molecule expression induced by thrombin and thrombin receptor agonist peptide (SFLLRNPNDKYEPF, TRAP) in cultured human umbilical vein endothelial cells. Thrombin and thrombin receptor agonist peptide induced endothelial leukocyte adhesion molecule-1 (ELAM-1) expression. Intercellular adhesion molecule-1 (ICAM-1) expression was also induced by thrombin, but not by TRAP. Baicalein isolated from Scutellariae Radix inhibited ELAM-1 expression induced by thrombin and thrombin receptor agonist peptide dose-dependently, with 50% inhibitory concentrations (IC50) of 5.53 +/- 1.68 microM and 2.44 +/- 1.08 microM, respectively. Furthermore, baicalein inhibited thrombin-induced ICAM-1 expression with an IC50 of 9.67 +/- 1.28 microM. In addition, baicalein inhibited the expressions of ELAM-1 and ICAM-1 stimulated by protein kinase C (PKC) activator phorbol myristate acetate (PMA).


Assuntos
Flavanonas , Flavonoides/isolamento & purificação , Plantas Medicinais/química , Sequência de Aminoácidos , Análise de Variância , Células Cultivadas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Selectina E/efeitos dos fármacos , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Feminino , Flavonoides/farmacologia , Humanos , Molécula 1 de Adesão Intercelular/efeitos dos fármacos , Medicina Tradicional Chinesa , Raízes de Plantas/química , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/efeitos dos fármacos , Proteínas/farmacologia , Receptores de Trombina , Acetato de Tetradecanoilforbol/farmacologia , Trombina/farmacologia , Veias Umbilicais/efeitos dos fármacos
12.
Proc Natl Acad Sci U S A ; 98(11): 6423-8, 2001 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-11353855

RESUMO

To visualize and isolate live dopamine (DA)-producing neurons in the embryonic ventral mesencephalon, we generated transgenic mice expressing green fluorescent protein (GFP) under the control of the rat tyrosine hydroxylase gene promoter. In the transgenic mice, GFP expression was observed in the developing DA neurons containing tyrosine hydroxylase. The outgrowth and cue-dependent guidance of GFP-labeled axons was monitored in vitro with brain culture systems. To isolate DA neurons expressing GFP from brain tissue, cells with GFP fluorescence were sorted by fluorescence-activated cell sorting. More than 60% of the sorted GFP(+) cells were positive for tyrosine hydroxylase, confirming that the population had been successfully enriched with DA neurons. The sorted GFP(+) cells were transplanted into a rat model of Parkinson's disease. Some of these cells survived and innervated the host striatum, resulting in a recovery from Parkinsonian behavioral defects. This strategy for isolating an enriched population of DA neurons should be useful for cellular and molecular studies of these neurons and for clinical applications in the treatment of Parkinson's disease.


Assuntos
Dopamina/metabolismo , Mesencéfalo/citologia , Neurônios/citologia , Doença de Parkinson , Animais , Axônios/fisiologia , Separação Celular , Transplante de Células , Células Cultivadas , Modelos Animais de Doenças , Citometria de Fluxo/métodos , Expressão Gênica , Proteínas de Fluorescência Verde , Proteínas Luminescentes/genética , Mesencéfalo/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/metabolismo , Ratos , Tirosina 3-Mono-Oxigenase/genética
13.
Vet Pathol ; 38(3): 346-50, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11355670

RESUMO

The mes rat is from an inbred mutant colony of rats with spontaneous eosinophilia. In order to investigate the pathogenesis of the mes rat, the histopathology and hematology for 76 mes rats were examined at several weeks of age. Tissue eosinophilia developed at 8 weeks of age when the blood eosinophil was 500 cells per microliter or more. Subsequently, eosinophilia progressed with age, and splenic eosinophilopoiesis and erythropoiesis appeared simultaneously. Many inflammatory lesions were induced after 10 weeks of age when the blood eosinophils became 1,000 cells per microliter or more. Gastroenteritis and mesenteric lymphadenitis were seen in 44 of 47 (94%) and 31 of 47 (66%) rats, respectively, after 10 weeks of age. Aortitis that deteriorated with age was found in 19 of 39 (49%) rats after 12 weeks of age. Hepatic fibrosis was found in four rats that exhibited severe eosinophilia and anemia. These results are comparable to the features of a hypereosinophilic syndrome in humans and other animals.


Assuntos
Eosinofilia/patologia , Síndrome Hipereosinofílica/veterinária , Doenças dos Roedores/patologia , Animais , Aorta Torácica/patologia , Modelos Animais de Doenças , Eosinofilia/sangue , Eosinofilia/genética , Eosinófilos/patologia , Feminino , Gastroenterite/patologia , Gastroenterite/veterinária , Histocitoquímica/veterinária , Síndrome Hipereosinofílica/patologia , Fígado/patologia , Linfadenite/patologia , Linfadenite/veterinária , Masculino , Ratos , Ratos Mutantes , Ratos Sprague-Dawley , Doenças dos Roedores/genética
14.
Exp Anim ; 49(3): 211-5, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11109544

RESUMO

Hematological and genetic characteristics of newly found eosinophilic rats were studied. Hematologically, high blood eosinophil counts started at 6 weeks of age. Almost all 10-week-old rats had eosinophilia with individual counts above 500/microliter and 5 to 100 times the normal level. Proliferating eosinophils had normal morphology. An increase in lymphocyte counts was observed at 5 weeks of age, one week earlier than the onset of eosinophilosis. In bone marrow, proliferation of eosinophils was also observed at 8 weeks of age and thereafter progressed, suggesting a role in the pathogenesis of eosinophilia in this rat. The results of genetic cross experiments revealed the disease to be hereditary. The spontaneously eosinophilic rat therefore warrants attention as a model for studying the underlying mechanisms of human and animal eosinophilia.


Assuntos
Eosinofilia/genética , Envelhecimento/fisiologia , Animais , Células da Medula Óssea/citologia , Divisão Celular , Cruzamentos Genéticos , Modelos Animais de Doenças , Eosinofilia/sangue , Feminino , Contagem de Leucócitos , Masculino , Ratos , Ratos Endogâmicos , Ratos Mutantes , Organismos Livres de Patógenos Específicos
15.
J Vet Med Sci ; 62(9): 971-5, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11039593

RESUMO

Aminoglycoside antibiotics are generally accepted to accumulate in renal proximal tubule cells from the luminal surface and show toxic effects on the cells. The binding affinity and membrane permeability of aminoglycoside antibiotics are different at the brush border membrane (BBM) and the basolateral membrane (BLM) of proximal tubule cells. This study was performed, therefore, to investigate the differential effects of the aminoglycoside antibiotic gentamicin (GM) on cultured LLC-PK1 cells, a pig kidney proximal epithelial cell line, after addition to the BBM or the BLM side. LLC-PK1 cells were cultured on microporous membranes until forming confluent monolayers, and then GM was added to either the BBM or the BLM side. GM caused release of enzymes from the organelles, with a higher level of release observed following addition to the BBM side than that to the BLM side. Patterns of [3H]GM uptake by the cells differed in a manner dependent on whether it was added to the BBM or the BLM side. That is, the cellular uptake from the BBM side increased with incubation time, while that from the BLM side showed rapid saturation. These results suggested that aminoglycoside antibiotics show differential effects on cultured proximal epithelial cells and have differential patterns of cellular uptake when added to the BBM or the BLM side.


Assuntos
Antibacterianos/toxicidade , Gentamicinas/toxicidade , Rim/efeitos dos fármacos , Animais , Antibacterianos/farmacocinética , Membrana Basal/efeitos dos fármacos , Membrana Basal/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Gentamicinas/farmacocinética , Rim/metabolismo , Células LLC-PK1 , Lisossomos/metabolismo , Masculino , Microvilosidades/efeitos dos fármacos , Microvilosidades/metabolismo , Suínos
16.
J Vet Med Sci ; 62(9): 977-81, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11039594

RESUMO

To clarify the mechanism of cephalosporin nephrotoxicity, the cytotoxic effects of cephaloridine (CER), a nephrotoxic cephalosporin antibiotic, on the pig kidney proximal tubular epithelial cell line (LLC-PK1) were studied in culture. CER increased the content of hydrogen peroxide and decreased the activity of catalase in the treated cells, followed by an increase in the content of lipid peroxide and decreases in both glutathione peroxidase activity and in the non-protein sulfhydryl content. The levels of NADPH-dependent hydrogen peroxide and superoxide anion production by microsomes prepared from LLC-PK1 cells, and by NADPH-cytochrome P-450 reductase purified from the rat renal cortex were significantly increased by paraquat. The production of these molecules was antagonized by p-chloromer-curibenzoate, an inhibitor of NADPH-cytochrome P-450 reductase. On the other hand, CER did not significantly affect the production of hydrogen peroxide or superoxide anions. These results suggested that the cytotoxic effect of CER on cultured LLC-PK1 cells was due to the increases in hydrogen peroxide and lipid peroxide levels and not microsomal oxygen radical production, and that the mechanism of this cytotoxicity is very different from that of paraquat which induces microsomal oxygen radical production.


Assuntos
Cefaloridina/toxicidade , Cefalosporinas/toxicidade , Rim/efeitos dos fármacos , Peroxidação de Lipídeos , Oxigênio/metabolismo , Animais , Catalase/metabolismo , Radicais Livres , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Rim/enzimologia , Rim/metabolismo , Córtex Renal/efeitos dos fármacos , Córtex Renal/metabolismo , Células LLC-PK1 , Peróxidos Lipídicos/metabolismo , Masculino , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Suínos
17.
J Toxicol Sci ; 25(3): 161-5, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10987122

RESUMO

In this study, a new simple method to measure erythrocyte fragility with stirring of diluted blood (stirring method) was introduced and evaluated with anemic rats given beta-acetylphenylhydrazine (APHZ) or clofibrate. APHZ at a dose of 40 mg/kg caused significant decreases in hemoglobin and hematocrit 24 hr after administration. However, the marked elevation of erythrocyte fragility was already detectable after 6 hr by our stirring method. At a dose of 10 mg/kg APHZ, although no significant changes in the erythrocytic parameters were observed throughout the experimental period (72 hr), the blood stirring method revealed a marked elevation of erythrocyte fragility 6 hr after administration. Similarly with clofibrate, no changes in erythrocytic parameters were noted following 100 mg/kg or 300 mg/kg administration, but the enhanced fragility was evident with the stirring method. Thus, using our approach, the erythrocyte fragility could be detected at an earlier stage and with greater sensitivity than by decreases in erythrocytic parameters. The results suggest that the stirring method will prove to be useful for detecting erythrocyte fragility in safety studies.


Assuntos
Anemia/sangue , Anticolesterolemiantes/farmacologia , Clofibrato/farmacologia , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Fenil-Hidrazinas/farmacologia , Anemia/induzido quimicamente , Animais , Tamanho Celular/efeitos dos fármacos , Contagem de Eritrócitos , Eritrócitos/ultraestrutura , Hematócrito , Hemoglobinas/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/ultraestrutura , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Fragilidade Osmótica/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
18.
Toxicol Appl Pharmacol ; 167(2): 151-6, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10964766

RESUMO

To clarify the mechanism of cephalosporin nephrotoxicity, the effects of cephaloridine (CLD), a nephrotoxic cephalosporin antibiotic, on the mitochondria of the pig kidney proximal tubular epithelial cell line LLC-PK(1) were studied in culture. The activity of cytochrome c oxidase in the mitochondria of LLC-PK(1) cells was significantly decreased from 9 h after addition of 1.0 mM CLD to the cultured cells. These effects were dose-dependent and accompanied with a significant decrease in the ATP content in the cells, followed by marked morphological changes in the mitochondria. These alterations were observed in the treated cells before the increase in lipid peroxidation. The activities of NADH-cytochrome c reductase and succinate dehydrogenase in the mitochondria and NADPH-cytochrome P450 reductase, NADH-cytochrome b(5) reductase, and 7-ethoxycoumarin O-deethylase in the microsomes of the treated cells were not affected. Superoxide anion production by the mitochondria prepared from LLC-PK(1) cells or NADH-cytochrome c reductase was not affected by addition of CLD (1-10 mM), but adriamycin (0.1 mM) or paraquat (0.1 mM) significantly increased the superoxide anion production. These results suggested that the primary action of CLD is inhibition of cytochrome c oxidase activity in the mitochondrial electron transport chain, which decreases intracellular ATP content in renal tubular epithelial cells and that these effects of CLD are followed by increased lipid peroxidation and cellular injury.


Assuntos
Cefaloridina/farmacologia , Cefalosporinas/farmacologia , Complexo IV da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Células Epiteliais/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Animais , Células Cultivadas , Doxorrubicina/farmacologia , Células Epiteliais/citologia , Células Epiteliais/ultraestrutura , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Microssomos/efeitos dos fármacos , Microssomos/enzimologia , Mitocôndrias/diagnóstico por imagem , Mitocôndrias/enzimologia , Paraquat/farmacologia , Suínos , Ultrassonografia
20.
J Neurosci ; 20(6): 2418-26, 2000 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10704516

RESUMO

Tyrosine hydroxylase (TH) is the initial and rate-limiting enzyme for the biosynthesis of catecholamines that are considered to be involved in a variety of neuropsychiatric functions. Here, we report behavioral and neuropsychological deficits in mice carrying a single mutated allele of the TH gene in which TH activity in tissues is reduced to approximately 40% of the wild-type activity. In the mice heterozygous for the TH mutation, noradrenaline accumulation in brain regions was moderately decreased to 73-80% of the wild-type value. Measurement of extracellular noradrenaline level in the frontal cortex by the microdialysis technique showed a reduction in high K(+)-evoked noradrenaline release in the mutants. The mutant mice displayed impairment in the water-finding task associated with latent learning performance. They also exhibited mild impairment in long-term memory formation in three distinct forms of associative learning, including active avoidance, cued fear conditioning, and conditioned taste aversion. These deficits were restored by the drug-induced stimulation of noradrenergic activity. In contrast, the spatial learning and hippocampal long-term potentiation were normal in the mutants. These results provide genetic evidence that the central noradrenaline system plays an important role in memory formation, particularly in the long-term memory of conditioned learning.


Assuntos
Hipocampo/fisiologia , Norepinefrina/metabolismo , Tirosina 3-Mono-Oxigenase/genética , Animais , Aprendizagem por Associação/fisiologia , Aprendizagem da Esquiva/fisiologia , Química Encefálica/genética , Quimera , Medo , Feminino , Lobo Frontal/citologia , Lobo Frontal/enzimologia , Heterozigoto , Hipocampo/citologia , Potenciação de Longa Duração/fisiologia , Masculino , Memória/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Mutantes Neurológicos , Microdiálise , Neurônios/enzimologia , Percepção Espacial/fisiologia , Tirosina 3-Mono-Oxigenase/metabolismo
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