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1.
Sci Rep ; 7: 41970, 2017 02 07.
Article in English | MEDLINE | ID: mdl-28169313

ABSTRACT

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.


Subject(s)
Algorithms , Blood Vessels/diagnostic imaging , Breast Neoplasms/blood supply , Breast/blood supply , Carcinoma, Ductal, Breast/blood supply , Photoacoustic Techniques/instrumentation , Photoacoustic Techniques/methods , Adult , Aged , Aged, 80 and over , Blood Vessels/pathology , Breast/diagnostic imaging , Breast/pathology , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/diagnostic imaging , Carcinoma, Ductal, Breast/pathology , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Middle Aged , Young Adult
2.
Connect Tissue Res ; 56(1): 44-9, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25372661

ABSTRACT

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.


Subject(s)
Aquaporin 2/metabolism , Odontoblasts/metabolism , TRPV Cation Channels/metabolism , Xylitol/pharmacology , Animals , Aquaporin 2/antagonists & inhibitors , Aquaporin 2/genetics , Hypertonic Solutions/pharmacology , Interleukin-6/metabolism , Kinetics , Lipopolysaccharides/pharmacology , Mice , Odontoblasts/drug effects , Osmotic Pressure/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Small Interfering/metabolism , TRPV Cation Channels/antagonists & inhibitors , TRPV Cation Channels/genetics , Time Factors
3.
Arzneimittelforschung ; 62(11): 537-44, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22972470

ABSTRACT

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.


Subject(s)
Hypoglycemic Agents/chemical synthesis , Pyridones/chemical synthesis , Receptors, G-Protein-Coupled/agonists , Animals , Gastric Emptying/drug effects , Glucagon-Like Peptide 1/blood , Hypoglycemic Agents/pharmacology , Male , Mice , Mice, Inbred C57BL , Pyridones/pharmacology , Structure-Activity Relationship
4.
Parasitology ; 134(Pt 7): 923-30, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17316473

ABSTRACT

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.


Subject(s)
Indoleamine-Pyrrole 2,3,-Dioxygenase/immunology , Malaria/immunology , Plasmodium yoelii/immunology , Tryptophan/immunology , Tryptophan/metabolism , Animals , Antimalarials/pharmacology , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/physiology , Chloroquine/pharmacology , Enzyme Activation , Enzyme Inhibitors/pharmacology , Erythrocytes/parasitology , Female , Indoleamine-Pyrrole 2,3,-Dioxygenase/antagonists & inhibitors , Indoleamine-Pyrrole 2,3,-Dioxygenase/drug effects , Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism , Interferon-gamma/blood , Kynurenine/blood , Malaria/metabolism , Mice , Mice, Inbred C57BL , Plasmodium yoelii/drug effects , Time Factors , Tryptophan/analogs & derivatives , Tryptophan/blood , Tryptophan/pharmacology
5.
J Periodontal Res ; 42(1): 53-61, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17214640

ABSTRACT

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.


Subject(s)
Anti-Bacterial Agents/pharmacology , Matrix Metalloproteinase Inhibitors , Periodontal Ligament/drug effects , Proto-Oncogene Protein c-ets-1/drug effects , Roxithromycin/pharmacology , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adult , Cells, Cultured , Down-Regulation/drug effects , Enzyme Activation/drug effects , Gene Expression Regulation/drug effects , Humans , JNK Mitogen-Activated Protein Kinases/antagonists & inhibitors , Male , Mitogen-Activated Protein Kinase 1/antagonists & inhibitors , Mitogen-Activated Protein Kinases/drug effects , Periodontal Ligament/cytology , Phosphorylation/drug effects , Transcription, Genetic/drug effects , p38 Mitogen-Activated Protein Kinases/drug effects
6.
Bioinformatics ; 22(13): 1668-9, 2006 Jul 01.
Article in English | MEDLINE | ID: mdl-16644790

ABSTRACT

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.


Subject(s)
Computational Biology/methods , Proteins/chemistry , Animals , Databases, Bibliographic , Databases, Factual , Databases, Protein , Humans , Information Storage and Retrieval , Phosphorylation , PubMed , Software , User-Computer Interface
7.
J Oral Rehabil ; 31(11): 1139-44, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15525394

ABSTRACT

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.


Subject(s)
Gutta-Percha , Root Canal Filling Materials , Humans , Materials Testing , Rheology
8.
Surg Endosc ; 17(12): 2028-31, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14598159

ABSTRACT

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.


Subject(s)
Cystadenoma, Serous/surgery , Laparoscopy/methods , Pancreatectomy/methods , Pancreatic Neoplasms/surgery , Adult , Cholangiopancreatography, Endoscopic Retrograde , Cystadenocarcinoma, Mucinous/diagnosis , Cystadenoma, Mucinous/diagnosis , Cystadenoma, Serous/diagnosis , Cystadenoma, Serous/pathology , Diagnosis, Differential , Equipment Design , Female , Hand , Hemostasis, Surgical/methods , Humans , Incidental Findings , Magnetic Resonance Imaging , Male , Middle Aged , Pancreatectomy/instrumentation , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/pathology , Splenic Artery , Splenic Vein , Surgical Stapling , Tomography, Emission-Computed , Tomography, X-Ray Computed
9.
Article in Chinese | MEDLINE | ID: mdl-15108514

ABSTRACT

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.


Subject(s)
Antigens, Protozoan/analysis , Antigens, Surface/analysis , Plasmodium berghei/immunology , Plasmodium yoelii/immunology , Protozoan Proteins/analysis , Animals , Antibodies, Monoclonal/immunology , Antigens, Protozoan/chemistry , Antigens, Protozoan/immunology , Antigens, Surface/chemistry , Antigens, Surface/immunology , Blotting, Western , Epitopes/immunology , Fluorescent Antibody Technique, Indirect , Mice , Protozoan Proteins/chemistry , Protozoan Proteins/immunology
10.
IEEE Trans Neural Netw ; 13(3): 752-6, 2002.
Article in English | MEDLINE | ID: mdl-18244471

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-11738712

ABSTRACT

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.


Subject(s)
Plasmodium falciparum/genetics , Plasmodium yoelii/genetics , Protozoan Proteins/genetics , Amino Acid Sequence , Animals , Antibodies, Monoclonal/biosynthesis , Antibodies, Monoclonal/immunology , Antibodies, Protozoan/biosynthesis , Antibodies, Protozoan/immunology , Cell Adhesion , Female , Malaria/parasitology , Malaria, Falciparum/parasitology , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Multigene Family , Plasmodium falciparum/growth & development , Plasmodium falciparum/pathogenicity , Plasmodium yoelii/growth & development , Plasmodium yoelii/pathogenicity , Protozoan Proteins/chemistry , Protozoan Proteins/immunology , Protozoan Proteins/metabolism
12.
J Parasitol ; 87(4): 928-30, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11534665

ABSTRACT

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.


Subject(s)
Blood/parasitology , Cell Culture Techniques/methods , Oogenesis , Plasmodium vivax/cytology , Animals , Anopheles/parasitology , Cell Differentiation , Female , Humans , Malaria, Vivax/parasitology , Plasmodium vivax/drug effects , Plasmodium vivax/growth & development , Xanthurenates/pharmacology
13.
J Endod ; 27(4): 273-7, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11485266

ABSTRACT

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.


Subject(s)
Dental Pulp/immunology , Interleukin-6/biosynthesis , Lipopolysaccharides/immunology , Prevotella intermedia/immunology , Antibodies, Monoclonal/immunology , Biological Assay , Blotting, Northern , Cell Culture Techniques , Cycloheximide/pharmacology , Dactinomycin/pharmacology , Dental Pulp/cytology , Dental Pulp/drug effects , Dental Pulp/microbiology , Gene Expression Regulation , Humans , Immunoenzyme Techniques , Interferon-gamma/pharmacology , Interleukin-10/pharmacology , Interleukin-4/pharmacology , Interleukin-6/genetics , Lipopolysaccharide Receptors/immunology , Protein Synthesis Inhibitors/pharmacology , Pulpitis/immunology , Pulpitis/microbiology , RNA, Messenger/genetics , Time Factors , Transcription, Genetic/genetics
14.
Mol Biochem Parasitol ; 116(1): 65-72, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11463467

ABSTRACT

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.


Subject(s)
Organelles/genetics , Plasmodium berghei/genetics , Protozoan Proteins/genetics , Amino Acid Sequence , Animals , Base Sequence , Cell Compartmentation , Cloning, Molecular , Conserved Sequence , Molecular Sequence Data , Plasmodium , Plasmodium berghei/pathogenicity , Protein Conformation , Sequence Analysis, DNA , von Willebrand Factor/genetics
15.
J Toxicol Sci ; 26(2): 61-73, 2001 May.
Article in English | MEDLINE | ID: mdl-11429969

ABSTRACT

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.


Subject(s)
Carcinogens/toxicity , Neoplasms, Experimental/chemically induced , Sulfamethoxazole/toxicity , Animals , Body Weight , Carcinogenicity Tests , Female , Genes, ras , Harderian Gland/pathology , Humans , Hyperplasia , Lung Neoplasms/pathology , Male , Methylnitrosourea/toxicity , Mice , Mice, Transgenic , Neoplasms, Experimental/pathology , Splenic Neoplasms/pathology , Sulfamethoxazole/administration & dosage , Thyroid Gland/pathology
16.
J Pharm Pharmacol ; 53(6): 823-9, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11428658

ABSTRACT

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.


Subject(s)
Anticonvulsants/pharmacokinetics , Imipenem/pharmacology , Thienamycins/pharmacology , Valproic Acid/pharmacokinetics , Administration, Oral , Animals , Biological Transport, Active , Drug Interactions , Infusions, Intravenous , Intestinal Absorption/drug effects , Male , Rats , Rats, Sprague-Dawley
17.
J Nutr Sci Vitaminol (Tokyo) ; 47(1): 32-9, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11349888

ABSTRACT

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.


Subject(s)
Adenocarcinoma/prevention & control , Adenoma/prevention & control , Antioxidants/administration & dosage , Carotenoids/administration & dosage , Deoxyguanosine/analogs & derivatives , Lung Neoplasms/prevention & control , Vehicle Emissions/toxicity , 8-Hydroxy-2'-Deoxyguanosine , Adenocarcinoma/chemically induced , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Adenoma/chemically induced , Adenoma/metabolism , Adenoma/pathology , Animals , Antioxidants/pharmacology , Carotenoids/pharmacology , DNA Damage/drug effects , Deoxyguanosine/analysis , Deoxyguanosine/genetics , Dietary Fats/administration & dosage , Growth/drug effects , Lung/chemistry , Lung/drug effects , Lung/metabolism , Lung Neoplasms/chemically induced , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Mice , Mice, Inbred ICR , Reactive Oxygen Species , Time Factors , Vitamins/blood , beta Carotene/metabolism
20.
Toxicol Pathol ; 29(6): 623-9, 2001.
Article in English | MEDLINE | ID: mdl-11794378

ABSTRACT

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.


Subject(s)
Bone Diseases, Metabolic/chemically induced , Ferrous Compounds/toxicity , Lactates/toxicity , Tibia/drug effects , Administration, Oral , Animals , Body Weight/drug effects , Bone Diseases, Metabolic/pathology , Male , Osteoclasts/drug effects , Rats , Rats, Sprague-Dawley , Tibia/pathology
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