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1.
Sci Rep ; 7: 41970, 2017 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-28169313

RESUMEN

Noninvasive measurement of the distribution and oxygenation state of hemoglobin (Hb) inside the tissue is strongly required to analyze the tumor-associated vasculatures. We developed a photoacoustic imaging (PAI) system with a hemispherical-shaped detector array (HDA). Here, we show that PAI system with HDA revealed finer vasculature, more detailed blood-vessel branching structures, and more detailed morphological vessel characteristics compared with MRI by the use of breast shape deformation of MRI to PAI and their fused image. Morphologically abnormal peritumoral blood vessel features, including centripetal photoacoustic signals and disruption or narrowing of vessel signals, were observed and intratumoral signals were detected by PAI in breast cancer tissues as a result of the clinical study of 22 malignant cases. Interestingly, it was also possible to analyze anticancer treatment-driven changes in vascular morphological features and function, such as improvement of intratumoral blood perfusion and relevant changes in intravascular hemoglobin saturation of oxygen. This clinical study indicated that PAI appears to be a promising tool for noninvasive analysis of human blood vessels and may contribute to improve cancer diagnosis.


Asunto(s)
Algoritmos , Vasos Sanguíneos/diagnóstico por imagen , Neoplasias de la Mama/irrigación sanguínea , Mama/irrigación sanguínea , Carcinoma Ductal de Mama/irrigación sanguínea , Técnicas Fotoacústicas/instrumentación , Técnicas Fotoacústicas/métodos , Adulto , Anciano , Anciano de 80 o más Años , Vasos Sanguíneos/patología , Mama/diagnóstico por imagen , Mama/patología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/diagnóstico por imagen , Carcinoma Ductal de Mama/patología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Persona de Mediana Edad , Adulto Joven
2.
Connect Tissue Res ; 56(1): 44-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25372661

RESUMEN

AIM: To examine the responses of mouse odontoblast-lineage cell line (OLC) cultures to xylitol-induced hypertonic stress. METHODOLOGY: OLCs were treated with xylitol, sucrose, sorbitol, mannitol, arabinose and lyxose. Cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium assay. The expression of transient receptor potential vanilloids (TRPV) 1, 3 and 4 was detected using a reverse transcriptase-polymerase chain reaction (RT-PCR) assay. The expression of aquaporin (AQP) 2 was detected using immunofluorescence and Western blotting analysis. The expression of interleukin-6 (IL-6) under xylitol-induced hypertonic stress was assessed using an enzyme-linked immunosorbent assay (ELISA). Small interfering ribonucleic acid (siRNA) for AQP-2 was used to inhibition assay. RESULTS: Xylitol-induced hypertonic stress did not decrease OLC viability, unlike the other sugars tested. OLCs expressed TRPV1, 3 and 4 as well as AQP2. Xylitol inhibited lipopolysaccharide (LPS)-induced IL-6 expression after 3 h of hypertonic stress. TRPV1 mRNA expression was upregulated by xylitol. Costimulation with HgCl2 (AQP inhibitor) and Ruthenium red (TRPV1 inhibitor) decreased cell viability with xylitol stimulation. OLCs treated with siRNA against TRPV1 exhibited decreased cell viability with xylitol stimulation. CONCLUSION: OLCs have high-cell viability under xylitol-induced hypertonic stress, which may be associated with TRPV1 and AQP2 expressions.


Asunto(s)
Acuaporina 2/metabolismo , Odontoblastos/metabolismo , Canales Catiónicos TRPV/metabolismo , Xilitol/farmacología , Animales , Acuaporina 2/antagonistas & inhibidores , Acuaporina 2/genética , Soluciones Hipertónicas/farmacología , Interleucina-6/metabolismo , Cinética , Lipopolisacáridos/farmacología , Ratones , Odontoblastos/efectos de los fármacos , Presión Osmótica/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo , Canales Catiónicos TRPV/antagonistas & inhibidores , Canales Catiónicos TRPV/genética , Factores de Tiempo
3.
Arzneimittelforschung ; 62(11): 537-44, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22972470

RESUMEN

G protein-coupled receptor 119 (GPCR 119 (GPR119)) agonists have received considerable attention as a promising therapeutic option for treatment of type 2 diabetes mellitus. GPR119 is one of the GPCRs expressed in pancreatic islet ß-cells and its activation enhances stimulation of insulin secretion in a glucose-dependent manner. We have recently described a series of 6-amino-1H-indan-1-ones as potent, selective, and orally bioavailable GPR119 agonists with an amino group that plays important roles not only in their drug-like properties, such as high aqueous solubility, but also in their potent agonistic activity. However, many of these compounds displayed strong to moderate inhibition of human ether-à-go-go related gene channel. Attenuation of the basicity of the amino group by replacing the adjacent benzene ring with electron-deficient heteroaromatic rings provided several heterocyclic cores among which 6-aminofuro[3,2-c]pyridin-3(2H)-one was selected as a promising scaffold. Further optimization around the side chain moiety led to the discovery of 17i, which showed not only strong human GPR119 agonistic activity (EC50=14 nM), but also beneficial effects on gastric emptying and plasma total glucagon-like peptide-1 levels in mice.


Asunto(s)
Hipoglucemiantes/síntesis química , Piridonas/síntesis química , Receptores Acoplados a Proteínas G/agonistas , Animales , Vaciamiento Gástrico/efectos de los fármacos , Péptido 1 Similar al Glucagón/sangre , Hipoglucemiantes/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Piridonas/farmacología , Relación Estructura-Actividad
4.
Parasitology ; 134(Pt 7): 923-30, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17316473

RESUMEN

Plasmodium spp. cause the worst parasitic diseases in humans and evade host immunity in complicated ways. Activated catabolism of tryptophan in dendritic cells is thought to suppress immunity, which is mediated by an inducible rate-limiting enzyme of tryptophan catabolism, indoleamine 2,3 dioxygenase (IDO), via both tryptophan depletion and production of toxic metabolites. In various infections, including malaria, IDO is known to be activated but its biological significance is unclear; therefore, we investigated whether malaria parasites induce IDO to suppress host immune responses. We found that enzymatic activity of IDO was elevated systematically in our mouse malaria model, and was abolished by in vivo IDO inhibition with 1-methyl tryptophan. Experimental infection with Plasmodium yoelii showed that IDO inhibition slightly suppressed parasite density in association with enhanced proliferation and IFN-gamma production by CD4+ T cells in response to malaria parasites. Our observations suggest that induction of IDO is one of the immune mechanisms of malaria parasites.


Asunto(s)
Indolamina-Pirrol 2,3,-Dioxigenasa/inmunología , Malaria/inmunología , Plasmodium yoelii/inmunología , Triptófano/inmunología , Triptófano/metabolismo , Animales , Antimaláricos/farmacología , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/fisiología , Cloroquina/farmacología , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Eritrocitos/parasitología , Femenino , Indolamina-Pirrol 2,3,-Dioxigenasa/antagonistas & inhibidores , Indolamina-Pirrol 2,3,-Dioxigenasa/efectos de los fármacos , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Interferón gamma/sangre , Quinurenina/sangre , Malaria/metabolismo , Ratones , Ratones Endogámicos C57BL , Plasmodium yoelii/efectos de los fármacos , Factores de Tiempo , Triptófano/análogos & derivados , Triptófano/sangre , Triptófano/farmacología
5.
J Periodontal Res ; 42(1): 53-61, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17214640

RESUMEN

BACKGROUND AND OBJECTIVE: In periodontitis, matrix metalloproteinases (MMPs) are upregulated in response to locally released inflammatory cytokines, resulting in pathologic processes. Roxithromycin is a 14-membered ring macrolide antibiotic with broad-spectrum antibacterial effects against oral pathogens and immunomodulatory effects. Recently, we reported that roxithromycin inhibits tumor necrosis factor (TNF)-alpha-induced vascular endothelial growth factor expression in human periodontal ligament (HPDL) cell cultures. In the present study, we examined the effect of roxithromycin on TNF-alpha-induced MMP-1 production by HPDL cells. MATERIAL AND METHODS: Cultured cells were incubated with 1% fetal bovine serum for 24 h, followed by treatment with 10 ng/ml TNF-alpha, 10 microM roxithromycin, and mitogen-activated protein kinase inhibitor at various concentrations. Culture supernatants and sediments were collected at different time-points and used for enzyme-linked immunosorbent assays, and northern and western blot analyses. RESULTS: In HPDL cell cultures, roxithromycin strongly inhibited TNF-alpha-induced MMP-1 mRNA expression and production. The inhibition of MMP-1 gene expression by roxithromycin was dependent on de novo protein synthesis and was regulated at the transcriptional level. Roxithromycin significantly inhibited TNF-alpha-induced c-Jun N-terminal kinase activation (JNP) and marginally inhibited extracellular signal-regulated kinase (ERK) 1/2 activation, but not p38 mitogen-activated protein kinase activation. Furthermore, roxithromycin reduced the induction of Ets-1, one of the critical factors in MMP-1 transcription. CONCLUSION: Roxithromycin inhibits TNF-alpha-mediated MMP-1 induction through the downregulation of ERK1/2 and JNK activation and the subsequent reduction of Ets-1, suggesting that roxithromycin may have therapeutic use in periodontitis and other chronic inflammatory conditions involving MMP-1 induction.


Asunto(s)
Antibacterianos/farmacología , Inhibidores de la Metaloproteinasa de la Matriz , Ligamento Periodontal/efectos de los fármacos , Proteína Proto-Oncogénica c-ets-1/efectos de los fármacos , Roxitromicina/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adulto , Células Cultivadas , Regulación hacia Abajo/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Masculino , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/efectos de los fármacos , Ligamento Periodontal/citología , Fosforilación/efectos de los fármacos , Transcripción Genética/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/efectos de los fármacos
6.
Bioinformatics ; 22(13): 1668-9, 2006 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-16644790

RESUMEN

A web-based version of the RLIMS-P literature mining system was developed for online mining of protein phosphorylation information from MEDLINE abstracts. The online tool presents extracted phosphorylation objects (phosphorylated proteins, phosphorylation sites and protein kinases) in summary tables and full reports with evidence-tagged abstracts. The tool further allows mapping of phosphorylated proteins to protein entries in the UniProt Knowledgebase based on PubMed ID and/or protein name. The literature mining, coupled with database association, allows retrieval of rich biological information for the phosphorylated proteins and facilitates database annotation of phosphorylation features.


Asunto(s)
Biología Computacional/métodos , Proteínas/química , Animales , Bases de Datos Bibliográficas , Bases de Datos Factuales , Bases de Datos de Proteínas , Humanos , Almacenamiento y Recuperación de la Información , Fosforilación , PubMed , Programas Informáticos , Interfaz Usuario-Computador
7.
J Oral Rehabil ; 31(11): 1139-44, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15525394

RESUMEN

The purpose of this investigation was to investigate the rheological properties of four commercially available gutta perchas for root canal filling. The relaxation modulus [Gr(0): instantaneous shear modulus] and specific volume of their materials were examined. In addition, the quantity of heat was also studied by differential scanning calorimeter. In a lower temperature range than the first-order transition temperature (melting point), the Gr(0) values of each material were almost identical. A marked decrease of Gr(0) was observed at the melting point, and the range of the first-order transition temperature at heating was from 42.0 to 60.0 degrees C. At higher temperatures than the first-order transition temperature of each material, a considerable difference in Gr(0) values was observed. The transition temperatures obtained by the results of the Gr(0), specific volume and quantity of heat agreed with one another. A marked specific volume change was observed at the first-order transition temperature. The technique using melted gutta percha may not be favourable compared with the conventional lateral condensation technique because melted gutta percha undergoes a large amount of shrinkage during setting.


Asunto(s)
Gutapercha , Materiales de Obturación del Conducto Radicular , Humanos , Ensayo de Materiales , Reología
8.
Surg Endosc ; 17(12): 2028-31, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14598159

RESUMEN

It is difficult to exclude the possibility of malignancy of pancreatic cystic tumors because a biopsy of the pancreas is hard to obtain. The indication of open surgery for those cystic tumors without evidence of malignancy is controversial. Therefore, laparoscopic or laparoscopically assisted procedure would be an adequate choice of treatment for cystic tumors of the pancreas. Hand-assisted laparoscopic distal pancreatectomy with preservation of the spleen and the splenic artery and vein was performed for two cases of pancreatic cystic tumors. Three ports and one hand port were used. After careful dissection and accurate hemostasis between the pancreas and splenic vessels, laparoscopic distal pancreatectomy was carried out using an endoscopic linear stapler. There were no perioperative complications. The pathological diagnoses were oligocystic serous cystadenoma and solitary cystic serous cystadenoma, respectively. Hand-assisted, spleen-preserving laparoscopic distal pancreatectomy with preservation of the splenic artery and vein is a feasible procedure for the treatment of benign or borderline-malignant cystic lesions of the distal pancreas.


Asunto(s)
Cistadenoma Seroso/cirugía , Laparoscopía/métodos , Pancreatectomía/métodos , Neoplasias Pancreáticas/cirugía , Adulto , Colangiopancreatografia Retrógrada Endoscópica , Cistadenocarcinoma Mucinoso/diagnóstico , Cistoadenoma Mucinoso/diagnóstico , Cistadenoma Seroso/diagnóstico , Cistadenoma Seroso/patología , Diagnóstico Diferencial , Diseño de Equipo , Femenino , Mano , Hemostasis Quirúrgica/métodos , Humanos , Hallazgos Incidentales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pancreatectomía/instrumentación , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patología , Arteria Esplénica , Vena Esplénica , Grapado Quirúrgico , Tomografía Computarizada de Emisión , Tomografía Computarizada por Rayos X
9.
Artículo en Chino | MEDLINE | ID: mdl-15108514

RESUMEN

OBJECTIVE: To detect the rhoptry and surface proteins of invasive stages of Plasmodium yoelii and P. berghei with monoclonal antibodies. METHODS: Subcellular localization of antigens was detected by IFA. The antigens of different stages of the two species malaria parasites were analyzed by Western blotting. RESULTS: The antigens of rhoptry are very complicated. There are similar epitopes of the rhoptry proteins detected between the two species of Plasmodium. The similar epitopes were also detected between ookinetes and merozoites of P. yoelii, and ookinete antigens between the two species. But there are different antigens detected between merozoites and ookinetes in P. yoelii. The sporozoite surface antigen of P. yoelii was not detected in the ookinetes and merozoites in the same species. CONCLUSION: There are similar epitopes in the rhoptry and surface antigens of different stages and different species of rodent malaria parasites. There are also distinct antigens among them.


Asunto(s)
Antígenos de Protozoos/análisis , Antígenos de Superficie/análisis , Plasmodium berghei/inmunología , Plasmodium yoelii/inmunología , Proteínas Protozoarias/análisis , Animales , Anticuerpos Monoclonales/inmunología , Antígenos de Protozoos/química , Antígenos de Protozoos/inmunología , Antígenos de Superficie/química , Antígenos de Superficie/inmunología , Western Blotting , Epítopos/inmunología , Técnica del Anticuerpo Fluorescente Indirecta , Ratones , Proteínas Protozoarias/química , Proteínas Protozoarias/inmunología
10.
IEEE Trans Neural Netw ; 13(3): 752-6, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-18244471

RESUMEN

This paper analyzes the effect of momentum on steepest descent training for quadratic performance functions. We demonstrate that there always exists a momentum coefficient that will stabilize the steepest descent algorithm, regardless of the value of the learning rate. We also demonstrate how the value of the momentum coefficient changes the convergence properties of the algorithm.

11.
Mol Biochem Parasitol ; 118(2): 223-31, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11738712

RESUMEN

Malarial merozoite rhoptries contain a high molecular mass protein complex called RhopH. RhopH is composed of three polypeptides, RhopH1, RhopH2, and RhopH3, encoded by distinct genes. Using monoclonal antibody-purified protein complex from both Plasmodium falciparum and Plasmodium yoelii, peptides were obtained by digestion of RhopH1 and their sequence determined either by mass spectrometry or Edman degradation. In both species the genes encoding RhopH1 were identified as members of the cytoadherence linked asexual gene (clag) family. In P. falciparum the family members on chromosome 3 were identified as encoding RhopH1. In P. yoelii two related genes were identified and sequenced. One of the genes, pyrhoph1a, was positively identified as encoding RhopH1 by the peptide analysis and the other gene, pyrhoph1a-p, was at least transcribed. Genes in the clag family present in both parasite species have a number of conserved features. The size and location of the P. yoelii protein complex in the rhoptries was confirmed. The first clag gene identified on chromosome 9 was implicated in cytoadherence, the binding of infected erythrocytes to host endothelial cells; this study shows that other members of the family encode merozoite rhoptry proteins, proteins that may be involved in merozoite-erythrocyte interactions. We propose that the family should be renamed as rhoph1/clag.


Asunto(s)
Plasmodium falciparum/genética , Plasmodium yoelii/genética , Proteínas Protozoarias/genética , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/inmunología , Anticuerpos Antiprotozoarios/biosíntesis , Anticuerpos Antiprotozoarios/inmunología , Adhesión Celular , Femenino , Malaria/parasitología , Malaria Falciparum/parasitología , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Familia de Multigenes , Plasmodium falciparum/crecimiento & desarrollo , Plasmodium falciparum/patogenicidad , Plasmodium yoelii/crecimiento & desarrollo , Plasmodium yoelii/patogenicidad , Proteínas Protozoarias/química , Proteínas Protozoarias/inmunología , Proteínas Protozoarias/metabolismo
12.
J Parasitol ; 87(4): 928-30, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11534665

RESUMEN

We developed a method for the in vitro production of mature Plasmodium vivax ookinetes. Gametocytemic blood was collected from 98 P. vivax-infected patients reporting to malaria clinics in Maesod and Maekasa Districts, Tak Province, Thailand. Briefly, gametogenesis was induced using xanthurenic acid and parasites were separated by density gradient centrifugation and then cultured in RPMI-1640, pH 7.8-8.2. At the same time that blood was collected, 200 Anopheles dirus mosquitoes were allowed to feed on each patient. Mosquito midguts were removed 2-36 hr postfeeding, and gut contents were smeared onto glass slides, as were cultured samples from varying time points. Slides were stained with Giemsa, and the in vitro and mosquito development of ookinetes compared. Mature ookinetes were produced in 48.0% (47/98) of in vitro cultures, with a total yield ranging from 10 to 248,500 (mean = 15,523, median = 600) ookinetes produced per 5 ml blood. The temporal development and the morphology of the P. vivax ookinetes produced in vitro was similar to that observed in the A. dirus mosquitoes. The method that we describe is simple, can be used at remote sites without sophisticated equipment, and yields high numbers of clean ookinetes. This method of producing mature P. vivax ookinetes will be a useful tool for studies on ookinetes in P. vivax endemic regions.


Asunto(s)
Sangre/parasitología , Técnicas de Cultivo de Célula/métodos , Oogénesis , Plasmodium vivax/citología , Animales , Anopheles/parasitología , Diferenciación Celular , Femenino , Humanos , Malaria Vivax/parasitología , Plasmodium vivax/efectos de los fármacos , Plasmodium vivax/crecimiento & desarrollo , Xanturenatos/farmacología
13.
J Endod ; 27(4): 273-7, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11485266

RESUMEN

Interleukin (IL)-6 expression in human dental pulp cell cultures after stimulation with Prevotella intermedia lipopolysaccharide (LPS) was investigated by Northern blot analysis, enzyme immunoassay, and bioassay. The IL-6 mRNA expression began to increase after 1 hr and continued after up to 8 hr of exposure on stimulation with 10 microg/ml of P. intermedia LPS. The bioactivity was dose-dependent on the concentration of P. intermedia LPS (0 to 100 microg/ml). The IL-6 mRNA expression was inhibited by actinomysin D and super-induced by cycloheximide. Anti-CD14 monoclonal antibody (MY4) inhibited the IL-6 mRNA expression when administered at a 0.5 microg/ml concentration before stimulation with P. intermedia LPS at 1 microg/ml. The immunoregulatory cytokines (interferon-gamma, IL-10, and IL-4) inhibited LPS-induced IL-6 production with a combined treatment. These results suggest the IL-6 expression by pulp cell cultures is CD14-dependent and regulated at the transcriptional level, and a combined treatment with immunoregulatory cytokines may be effective for control of pulpal inflammation due to P. intermedia LPS.


Asunto(s)
Pulpa Dental/inmunología , Interleucina-6/biosíntesis , Lipopolisacáridos/inmunología , Prevotella intermedia/inmunología , Anticuerpos Monoclonales/inmunología , Bioensayo , Northern Blotting , Técnicas de Cultivo de Célula , Cicloheximida/farmacología , Dactinomicina/farmacología , Pulpa Dental/citología , Pulpa Dental/efectos de los fármacos , Pulpa Dental/microbiología , Regulación de la Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Interferón gamma/farmacología , Interleucina-10/farmacología , Interleucina-4/farmacología , Interleucina-6/genética , Receptores de Lipopolisacáridos/inmunología , Inhibidores de la Síntesis de la Proteína/farmacología , Pulpitis/inmunología , Pulpitis/microbiología , ARN Mensajero/genética , Factores de Tiempo , Transcripción Genética/genética
14.
Mol Biochem Parasitol ; 116(1): 65-72, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11463467

RESUMEN

The mosquito-invasive form of the malarial parasite, the ookinete, develops numerous secretory organelles, called micronemes, in the apical cytoplasm. Micronemal proteins are thought to be secreted during midgut invasion and to play a crucial role in attachment and motility of the ookinete. We found a novel ookinete micronemal protein of rodent malarial parasite Plasmodium berghei, named P. berghei von Willebrand factor A domain-related protein (PbWARP), and report it here as a putative soluble adhesive protein of the ookinete. The PbWARP gene contained a single open reading frame encoding a putative secretory protein of 303 amino acids, with a von Willebrand factor type A module-like domain as a main component. Western blot analysis demonstrated that PbWARP was firstly produced 12 h after fertilization by maturing ookinetes as SDS-resistant complexes. Recombinant PbWARP produced with a baculovirus system also formed SDS-resistant high-order oligomers. Immuno-electron microscopic studies showed that PbWARP was randomly distributed in the micronemes. PbWARP homologues also exist in human malarial parasites, Plasmodium falciparum and Plasmodium vivax. Highly conserved primary structures of PbWARP homologues among these phylogenetically distant Plasmodium species suggest their functional significance and the presence of a common invasion mechanism widely utilized throughout Plasmodium parasites.


Asunto(s)
Orgánulos/genética , Plasmodium berghei/genética , Proteínas Protozoarias/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Compartimento Celular , Clonación Molecular , Secuencia Conservada , Datos de Secuencia Molecular , Plasmodium , Plasmodium berghei/patogenicidad , Conformación Proteica , Análisis de Secuencia de ADN , Factor de von Willebrand/genética
15.
J Toxicol Sci ; 26(2): 61-73, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11429969

RESUMEN

Sulfamethoxazole (SMX), a hormone-mediated rodent-specific nongenotoxic carcinogen, was administered to CB6F1 mice carrying a human prototype c-Ha-ras gene (Tg-rasH2) at doses of 0, 25, 100 or 400 mg/kg/day and to the wild-type mice at a dose of 400 mg/kg/day in feed for 26 weeks to evaluate the carcinogenicity and to validate the Tg-rasH2 model. N-Methyl-N-nitrosourea was administered at an intraperitoneal dose of 75 mg/kg to Tg-rasH2 as a positive control and the experimental system was confirmed to be valid. Histopathological examination revealed adenomas of the lung and Harderian gland and hemangiosarcoma of the spleen at low frequencies in the Tg-rasH2 treated with SMX; however, no statistically significant differences were observed either in the onset or prevalence rates of these neoplasms compared with that in the control group. Between the wild-type mice and Tg-rasH2, the onset rate and prevalence of the neoplasms were not significantly different, but the neoplasms tended to be more frequent in Tg-rasH2 mice showing a sensitivity to tumorigenicity. Follicular epithelial cell hyperplasia was observed in the thyroid gland in the groups of Tg-rasH2 given 100 mg/kg SMX or more, but no neoplastic lesion was observed. SMX was judged to be negative for carcinogenic potential in Tg-rasH2 in the present study.


Asunto(s)
Carcinógenos/toxicidad , Neoplasias Experimentales/inducido químicamente , Sulfametoxazol/toxicidad , Animales , Peso Corporal , Pruebas de Carcinogenicidad , Femenino , Genes ras , Glándula de Harder/patología , Humanos , Hiperplasia , Neoplasias Pulmonares/patología , Masculino , Metilnitrosourea/toxicidad , Ratones , Ratones Transgénicos , Neoplasias Experimentales/patología , Neoplasias del Bazo/patología , Sulfametoxazol/administración & dosificación , Glándula Tiroides/patología
16.
J Pharm Pharmacol ; 53(6): 823-9, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11428658

RESUMEN

The concomitant use of carbapenem antibiotics with valproic acid has been prohibited because panipenem induced a decrease in plasma concentration of valproic acid in epileptic patients during valproic acid therapy. To clarify the possible mechanism of the carbapenem-valproic acid interaction, we investigated the effect of imipenem on the pharmacokinetic behaviour of valproic acid in rats. Co-administration of imipenem (30 mg kg(-1), i.v.) induced a decrease in the peak plasma concentration of valproic acid after oral administration. However, the imipenem-induced decrease in plasma concentrations of valproic acid was not observed within 60 min after intravenous injection of valproic acid. By utilizing in-situ vascular and luminal perfused small intestine, it was confirmed that absorption of valproic acid from the luminal to the vascular perfusate was decreased in the presence of imipenem (0.5 mM) in the vascular perfusate. The everted gut sac method was used to determine the effect of imipenem on active transport of valproic acid. The accumulation of valproic acid on the serosal side of the intestinal sac against the concentration gradient was reduced by lactic acid that inhibits the carrier-mediated transport of valproic acid across the intestinal brush-border membrane. However, imipenem did not affect the active transport of valproic acid. Therefore, the inhibition by imipenem of valproic acid absorption may be caused by a mechanism different from that of lactic acid. In conclusion, imipenem inhibits the intestinal absorption of valproic acid, which contributes to the decrease in plasma concentration of valproic acid after oral administration.


Asunto(s)
Anticonvulsivantes/farmacocinética , Imipenem/farmacología , Tienamicinas/farmacología , Ácido Valproico/farmacocinética , Administración Oral , Animales , Transporte Biológico Activo , Interacciones Farmacológicas , Infusiones Intravenosas , Absorción Intestinal/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-Dawley
17.
J Nutr Sci Vitaminol (Tokyo) ; 47(1): 32-9, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11349888

RESUMEN

The purpose of this study is to examine the carotenoid effects on lung tumorigenesis induced by intratracheal instillation of diesel exhaust particles (DEP) into mice weekly for 20 wk. It was suggested that active oxygen radicals might play an important role in DEP-induced lung tumorigenesis. Mice were divided to 4 groups of diet containing 0.02% of palm oil carotene, 0.02% of beta-carotene, or no carotenoid with or without DEP. The BF group (4% fat) and the HF group (16% fat) were prepared for each diet group. The experimental period was 12 mo. By the administration of palm oil carotene, neither adenocarcinoma nor adenoma was found in the BF group. In the HF group with palm oil carotene, no adenocarcinoma was observed, and adenoma was reduced. Adenoma in the HF group was not greatly reduced by beta-carotene, but rather increased in the BF group. No adenocarcinoma was found in either the BF or the HF groups with beta-carotene. The 8-hydroxydeoxyguanosine/deoxyguanosine ratio in palm carotene groups was lower than in the other groups, while that in beta-carotene groups was not. From these results, palm oil carotene was suggested to prevent lung tumorigenesis by its protective effect on DNA from active oxygen. Beta-carotene was supposed to have different effects from palm oil carotene on lung tumorigenesis. Besides the chemopreventive effect, the growth of mice was inhibited by the administration of palm oil carotene. Further studies are necessary to elucidate the mechanisms of carotenoid effects.


Asunto(s)
Adenocarcinoma/prevención & control , Adenoma/prevención & control , Antioxidantes/administración & dosificación , Carotenoides/administración & dosificación , Desoxiguanosina/análogos & derivados , Neoplasias Pulmonares/prevención & control , Emisiones de Vehículos/toxicidad , 8-Hidroxi-2'-Desoxicoguanosina , Adenocarcinoma/inducido químicamente , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Adenoma/inducido químicamente , Adenoma/metabolismo , Adenoma/patología , Animales , Antioxidantes/farmacología , Carotenoides/farmacología , Daño del ADN/efectos de los fármacos , Desoxiguanosina/análisis , Desoxiguanosina/genética , Grasas de la Dieta/administración & dosificación , Crecimiento/efectos de los fármacos , Pulmón/química , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Masculino , Ratones , Ratones Endogámicos ICR , Especies Reactivas de Oxígeno , Factores de Tiempo , Vitaminas/sangre , beta Caroteno/metabolismo
20.
Toxicol Pathol ; 29(6): 623-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11794378

RESUMEN

Osteopenia was induced in rats fed a diet containing 50,000 ppm (5%) iron lactate for 2 or 4 weeks. Blood chemistry, urinalysis, and bone histomorphometry of the proximal tibial metaphysis were performed. Urinary pyridinoline and deoxypyridinoline and the osteoclast number per bone surface were selected for the measurement of dynamic resorption. The osteoclast surface, eroded surface, and osteoblast surface increased at both ends of the exposure periods, and bone resorption and formation both increased. The bone volume, trabecular thickness, and trabecular number decreased, and the secondary spongiosa of proximal metaphysis showed a marked bone loss. However, no mineralization defect was observed. At the end of the 2-week exposure period, biomarkers of osteoclasts and osteoblasts had increased the most, and the osteoblast surface, osteoclast surface, and osteoclast number per bone surface increased with prolonged exposure. The pathological changes of the bone lesion in iron lactate-overloaded rats were similar to those in rats of the osteoporotic model, because they consisted of changes reflecting the increase of bone resorption and formation without an osteomalacic change. However, the decline of serum parathyroid hormone (PTH) levels was different from that of the osteoporosis model rat. We concluded iron-induced bone lesions probably differ from those of low turnover bone diseases.


Asunto(s)
Enfermedades Óseas Metabólicas/inducido químicamente , Compuestos Ferrosos/toxicidad , Lactatos/toxicidad , Tibia/efectos de los fármacos , Administración Oral , Animales , Peso Corporal/efectos de los fármacos , Enfermedades Óseas Metabólicas/patología , Masculino , Osteoclastos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Tibia/patología
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