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1.
Spinal Cord ; 54(7): 521-9, 2016 Jul.
Article de Anglais | MEDLINE | ID: mdl-26481711

RÉSUMÉ

STUDY DESIGN: Experimental training model of rats with spinal cord injury (SCI). SETTING: Osaka, JapanObjective:To investigate the effect of forced treadmill training by plantar placement (PP), as compared with dorsal placement (DP), of the dorsal paws on the locomotor behaviors of spinal cord-injured rats. METHODS: The spinal cord was contusion-injured at the thoracic level. Rats were divided into three groups: forced training involving stepping by PP and DP and non-forced training/assistance (nT). Training began 1 week after injury and was conducted for 4 weeks. Locomotor behaviors were estimated using Basso-Beattie-Bresnahan (BBB) scores, dorsiflexion of the hind paws and footprints of the hind paws. Histological and immunohistochemical examinations of the spinal cord lesions were conducted after 4 weeks of training. RESULTS: The values, respectively, of PP, DP and nT groups at 4 weeks of training were as follows: BBB scores were 15.6±0.8, 7.7±1.3 and 10.3±0.4. The paw dorsiflexion angles were 34.1±5.2, 16.4±2.4 and 23.6±3.0 degrees, respectively. The stride angles were 5.1±0.9, 13.7±4.9 and 17.8±4.0 degrees for the left paws. Cavity volumes were 10.3±2.1, 31.0±2.0 and 28.2±4.9%. In addition to cavities, there were astrocyte-devoid areas containing some loose tissues, through which many axons extended longitudinally. CONCLUSIONS: The BBB score, dorsiflexion angle and stride angle were consistently improved in the PP group. Cavity formation was more reduced, and many axons extended through coarse tissues formed in astrocyte-devoid areas at the lesion in the PP group. Forced training by PP of the hind paws promoted the behavioral and histological improvement of rats with SCI.


Sujet(s)
Épreuve d'effort/méthodes , Traitement par les exercices physiques/méthodes , Locomotion/physiologie , Membre inférieur/physiopathologie , Récupération fonctionnelle/physiologie , Traumatismes de la moelle épinière/rééducation et réadaptation , Animaux , Axones/métabolisme , Axones/anatomopathologie , Modèles animaux de maladie humaine , Femelle , Protéine gliofibrillaire acide/métabolisme , Performance psychomotrice , Rats , Rat Sprague-Dawley , Moelle spinale/anatomopathologie , Traumatismes de la moelle épinière/anatomopathologie
2.
Eur J Pharmacol ; 689(1-3): 72-80, 2012 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-22659113

RÉSUMÉ

Zonisamide has been proven as an effective drug for the recovery of degenerating dopaminergic neurons in the animal models of Parkinson's disease. However, several lines of evidence have questioned the neuroprotective capacity of zonisamide in animal models of Parkinson's disease. Although it suppresses dopaminergic neurodegeneration in animal models, the cellular and molecular mechanisms underlying the effectiveness of zonisamide are not fully understood. The current study demonstrates the effects of zonisamide on astrocyte cultures and two 6-hydroxydopamine-induced models of Parkinson's disease. Using primary astrocyte cultures, we showed that zonisamide up-regulated the expression of mRNA encoding mesencephalic astrocyte-derived neurotrophic factor, vascular endothelial growth factor, proliferating cell nuclear antigen, metallothionein-2, copper/zinc superoxide dismutase, and manganese superoxide dismutase. Similar responses to zonisamide were found in substantia nigra where the rats were pre-treated with 6-hydroxydopamine. Notably, pharmacological inhibition of 6-hydroxydopamine-induced toxicity by zonisamide pre-treatment was also confirmed using rat mesencephalic organotypic slice cultures of substantia nigra. In addition to this, zonisamide post-treatment also attenuated the nigral tyrosine hydroxylase-positive neuronal loss induced by 6-hydroxydopamine. Taken together, these studies demonstrate that zonisamide protected dopamine neurons in two Parkinson's disease models through a novel mechanism, namely increasing the expression of some important astrocyte-mediated neurotrophic and anti-oxidative factors.


Sujet(s)
Antioxydants/pharmacologie , Astrocytes/effets des médicaments et des substances chimiques , Isoxazoles/pharmacologie , Facteurs de croissance nerveuse/biosynthèse , ARN messager/biosynthèse , Régulation positive/effets des médicaments et des substances chimiques , Animaux , Animaux nouveau-nés , Astrocytes/métabolisme , Cellules cultivées , Mâle , Techniques de culture d'organes , Rats , Rat Wistar , Régulation positive/physiologie , Zonisamide
3.
Clin Exp Obstet Gynecol ; 39(4): 547-9, 2012.
Article de Anglais | MEDLINE | ID: mdl-23444767

RÉSUMÉ

Although severe Asherman's syndrome is a disease that may cause infertility, pregnancy and childbirth are possible by performing hysteroscopic surgery. However, the obstetrical outcome is not always satisfactory. We report a case where severe Asherman's syndrome occurred following a cesarean section. Hysteroscopic surgery was performed due to secondary infertility, and pregnancy was achieved through a subsequent intracytoplasmic sperm injection. At 23 weeks of gestation, the patient was hospitalized due to the threat of premature labor, and a cesarean section was performed at 29 weeks of gestation after pregnancy-induced hypertension occurred. It was determined to be abnormal adherent placentation such as placenta increta through intraoperative findings, and a cesarean hysterectomy was performed. The pathological diagnosis of the uterus was placenta increta. Due to the risk of complications from placenta increta in pregnancies following hysteroscopic surgery in patients with severe Asherman's syndrome, it is important to realize the high risk involved in such cases during the pregnancy course, and careful perinatal management should be required.


Sujet(s)
Gynatrésie/complications , Gynatrésie/chirurgie , Hystéroscopie , Placenta accreta , Issue de la grossesse , Injections intracytoplasmiques de spermatozoïdes , Césarienne itérative , Femelle , Humains , Hypertension artérielle gravidique , Hystérectomie , Hystérosalpingographie , Myomètre/anatomopathologie , Placenta accreta/imagerie diagnostique , Placenta accreta/étiologie , Placenta accreta/chirurgie , Placentation/physiologie , Grossesse , Injections intracytoplasmiques de spermatozoïdes/effets indésirables
4.
SAR QSAR Environ Res ; 21(5-6): 403-13, 2010 Jul.
Article de Anglais | MEDLINE | ID: mdl-20818579

RÉSUMÉ

The KAshinhou Tool for Ecotoxicity (KATE) system, including ecotoxicity quantitative structure-activity relationship (QSAR) models, was developed by the Japanese National Institute for Environmental Studies (NIES) using the database of aquatic toxicity results gathered by the Japanese Ministry of the Environment and the US EPA fathead minnow database. In this system chemicals can be entered according to their one-dimensional structures and classified by substructure. The QSAR equations for predicting the toxicity of a chemical compound assume a linear correlation between its log P value and its aquatic toxicity. KATE uses a structural domain called C-judgement, defined by the substructures of specified functional groups in the QSAR models. Internal validation by the leave-one-out method confirms that the QSAR equations, with r(2 )> 0.7, RMSE 5, give acceptable q(2) values. Such external validation indicates that a group of chemicals with an in-domain of KATE C-judgements exhibits a lower root mean square error (RMSE). These findings demonstrate that the KATE system has the potential to enable chemicals to be categorised as potential hazards.


Sujet(s)
Écotoxicologie/méthodes , Polluants environnementaux/composition chimique , Polluants environnementaux/toxicité , Relation quantitative structure-activité , Animaux , Poissons/physiologie , Japon , Modèles statistiques
5.
Parkinsonism Relat Disord ; 15(5): 351-3, 2009 Jun.
Article de Anglais | MEDLINE | ID: mdl-18823813

RÉSUMÉ

We determined plasma amantadine concentrations in patients with Parkinson's disease (PD) in daily clinical practice and investigated the relationship between plasma concentration and adverse reactions to clarify the safe therapeutic range. Seventy-eight consecutive PD patients on stable amantadine treatment were recruited. Plasma concentration of amantadine was measured 3h after the administration of morning amantadine dose. Serum creatinine was measured to estimate renal function. The mean daily dose of amantadine was 135.1+/-62.3mg/day, and the mean plasma amantadine concentration was 812.5+/-839.5 ng/ml (range, 91-4400 ng/ml). Plasma amantadine concentration increased according to increasing renal dysfunction. Three patients exhibited adverse reactions, such as myoclonus, hallucinations, and delirium, and all of them showed plasma amantadine concentration >3000 ng/ml. None of the three cases had previously shown such side effects. PD patients who have not developed any psychiatric symptoms as adverse reactions to the treatment may develop myoclonus, hallucination, or delirium when the plasma concentration of amantadine exceeds 3000 ng/ml. It is therefore recommended to use amantadine at the plasma concentration of less than 3000 ng/ml in the treatment of Parkinson's disease, especially in elderly patients.


Sujet(s)
Amantadine/effets indésirables , Amantadine/sang , Antiparkinsoniens/sang , Maladie de Parkinson/traitement médicamenteux , Adulte , Sujet âgé , Amantadine/usage thérapeutique , Antiparkinsoniens/effets indésirables , Antiparkinsoniens/usage thérapeutique , Créatinine/sang , Créatinine/métabolisme , Délire avec confusion/induit chimiquement , Femelle , Hallucinations/induit chimiquement , Humains , Mâle , Adulte d'âge moyen , Myoclonie/induit chimiquement , Maladie de Parkinson/sang , Maladie de Parkinson/physiopathologie , Indice de gravité de la maladie
6.
Acta Neurochir (Wien) ; 150(8): 823-7; discussion 827, 2008 Aug.
Article de Anglais | MEDLINE | ID: mdl-18615234

RÉSUMÉ

A 64-year-old woman with Parkinson is disease had a severe resting tremor that was not completely relieved by right-sided gamma knife thalamotomy (GKT). We performed bilateral staged thalamic deep brain stimulation (DBS) and compared the right and left ventral intermediate nucleus (Vim) of the thalamus including the frequency of single units recorded with microelectrodes, and also the somatotopical distribution of kinaesthetic cells (Ki). The average frequency of units for the presumed left Vim exceeded that of the right (22.6 +/- 19.2 Hz vs. 14.3 +/- 8.8 Hz). Regarding the somatotopic distribution of Ki, the receptive field for the leg, which is usually situated in the dorsolateral Vim, was more widely scattered in the right Vim than the non-lesioned left side. Our findings raise the possibility that the specific properties of the neurons changed due to partial coagulation by GKT within both the coagulated and the surrounding thalamic lesions.


Sujet(s)
Stimulation cérébrale profonde , Électroencéphalographie , Kinesthésie/physiologie , Plasticité neuronale/physiologie , Maladie de Parkinson/chirurgie , Complications postopératoires/physiopathologie , Radiochirurgie , Thalamus/chirurgie , Noyaux ventraux du thalamus/physiopathologie , Cartographie cérébrale , Association thérapeutique , Dominance cérébrale/physiologie , Femelle , Humains , Adulte d'âge moyen , Neurones/physiologie , Maladie de Parkinson/physiopathologie , Complications postopératoires/diagnostic , Thalamus/physiopathologie
7.
Br J Cancer ; 98(6): 1147-56, 2008 Mar 25.
Article de Anglais | MEDLINE | ID: mdl-18283316

RÉSUMÉ

Although mutation of APC or CTNNB1 (beta-catenin) is rare in breast cancer, activation of Wnt signalling is nonetheless thought to play an important role in breast tumorigenesis, and epigenetic silencing of Wnt antagonist genes, including the secreted frizzled-related protein (SFRP) and Dickkopf (DKK) families, has been observed in various tumours. In breast cancer, frequent methylation and silencing of SFRP1 was recently documented; however, altered expression of other Wnt antagonist genes is largely unknown. In the present study, we found frequent methylation of SFRP family genes in breast cancer cell lines (SFRP1, 7 out of 11, 64%; SFRP2, 11 out of 11, 100%; SFRP5, 10 out of 11, 91%) and primary breast tumours (SFRP1, 31 out of 78, 40%; SFRP2, 60 out of 78, 77%; SFRP5, 55 out of 78, 71%). We also observed methylation of DKK1, although less frequently, in cell lines (3 out of 11, 27%) and primary tumours (15 out of 78, 19%). Breast cancer cell lines express various Wnt ligands, and overexpression of SFRPs inhibited cancer cell growth. In addition, overexpression of a beta-catenin mutant and depletion of SFRP1 using small interfering RNA synergistically upregulated transcriptional activity of T-cell factor/lymphocyte enhancer factor. Our results confirm the frequent methylation and silencing of Wnt antagonist genes in breast cancer, and suggest that their loss of function contributes to activation of Wnt signalling in breast carcinogenesis.


Sujet(s)
Tumeurs du sein/génétique , Épigenèse génétique , Protéines de l'oeil/génétique , Protéines et peptides de signalisation intercellulaire/génétique , Protéines membranaires/génétique , Protéines de type Wingless/physiologie , Protéines adaptatrices de la transduction du signal , Lignée cellulaire tumorale , Méthylation de l'ADN , Femelle , Extinction de l'expression des gènes , Gènes suppresseurs de tumeur , Humains
8.
Int J Androl ; 31(1): 60-6, 2008 Feb.
Article de Anglais | MEDLINE | ID: mdl-17459123

RÉSUMÉ

Balanced reciprocal and Robertsonian translocations are the most common structural chromosome abnormalities in humans, with incidences of 0.7 and 1.23 per 1000. These translocations can affect fertility and/or pregnancy outcome because of possibly impaired production of gametes with an unbalanced zygote caused by the parental arrangement. Fertility problems in male translocation carriers are because of various degrees of sperm alterations that are directly related to the disturbance of the meiotic process. Investigation of human sperm chromosomes was performed by karyotyping spermatozoa after penetration of zona-free hamster oocytes, karyotype analysis now being possible to analyse the segregation patterns by using fluorescent in situ hybridization (FISH). Here, we document the results of meiotic segregation analysis for four Robertsonian and four reciprocal translocation carriers by FISH. In the sperm of Robertsonian translocation males, the majority of spermatozoa were normal/balanced. On the other hand, males with reciprocal translocations demonstrated a high rate of unbalanced spermatozoa of about 50% on meiotic segregation, with an unusually high rate (23.5%) of 3 : 1 segregation. This knowledge can be used for genetic counselling of families with these types of translocations.


Sujet(s)
Ségrégation des chromosomes , Hétérozygote , Hybridation fluorescente in situ , Méiose/physiologie , Spermatozoïdes/cytologie , Translocation génétique , Adulte , Animaux , Cricetinae , Femelle , Humains , Caryotypage , Mâle , Interaction sperme-ovule
9.
Oncogene ; 26(32): 4699-713, 2007 Jul 12.
Article de Anglais | MEDLINE | ID: mdl-17297461

RÉSUMÉ

Activation of Wnt signaling has been implicated in gastric tumorigenesis, although mutations in APC (adenomatous polyposis coli), CTNNB1 (beta-catenin) and AXIN are seen much less frequently in gastric cancer (GC) than in colorectal cancer. In the present study, we investigated the relationship between activation of Wnt signaling and changes in the expression of secreted frizzled-related protein (SFRP) family genes in GC. We frequently observed nuclear beta-catenin accumulation (13/15; 87%) and detected the active form of beta-catenin in most (12/16; 75%) GC cell lines. CpG methylation-dependent silencing of SFRP1, SFRP2 and SFRP5 was frequently seen among GC cell lines (SFRP1, 16/16, 100%; SFRP2, 16/16, 100%; SFRP5, 13/16, 81%) and primary GC specimens (SFRP1, 42/46, 91%; SFRP2, 44/46, 96%; SFRP5, 30/46, 65%), and treatment with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine rapidly restored SFRP expression. Ectopic expression of SFRPs downregulated T-cell factor/lymphocyte enhancer factor transcriptional activity, suppressed cell growth and induced apoptosis in GC cells. Analysis of global expression revealed that overexpression of SFRP2 repressed Wnt target genes and induced changes in the expression of numerous genes related to proliferation, growth and apoptosis in GC cells. It thus appears that aberrant SFRP methylation is one of the major mechanisms by which Wnt signaling is activated in GC.


Sujet(s)
Carcinomes/génétique , Épigenèse génétique , Protéines proto-oncogènes/génétique , Tumeurs de l'estomac/génétique , Protéines de type Wingless/génétique , Carcinomes/composition chimique , Lignée cellulaire tumorale , Ilots CpG , Méthylation de l'ADN , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes tumoraux , Humains , Protéines proto-oncogènes/analyse , Transduction du signal , Tumeurs de l'estomac/composition chimique , Facteurs de transcription TCF/antagonistes et inhibiteurs
10.
Br J Cancer ; 94(6): 914-21, 2006 Mar 27.
Article de Anglais | MEDLINE | ID: mdl-16479257

RÉSUMÉ

Transcription factor 2 gene (TCF2) encodes hepatocyte nuclear factor 1beta (HNF1beta), a transcription factor associated with development and metabolism. Mutation of TCF2 has been observed in renal cell cancer, and by screening aberrantly methylated genes, we have now identified TCF2 as a target for epigenetic inactivation in ovarian cancer. TCF2 was methylated in 53% of ovarian cancer cell lines and 26% of primary ovarian cancers, resulting in loss of the gene's expression. TCF2 expression was restored by treating cells with a methyltransferase inhibitor, 5-aza-2'deoxycitidine (5-aza-dC). In addition, chromatin immunoprecipitation showed deacetylation of histone H3 in methylated cells and, when combined with 5-aza-dC, the histone deacetylase inhibitor trichostatin A synergistically induced TCF2 expression. Epigenetic inactivation of TCF2 was also seen in colorectal, gastric and pancreatic cell lines, suggesting general involvement of epigenetic inactivation of TCF2 in tumorigenesis. Restoration of TCF2 expression induced expression of HNF4alpha, a transcriptional target of HNF1beta, indicating that epigenetic silencing of TCF2 leads to alteration of the hepatocyte nuclear factor network in tumours. These results suggest that TCF2 is involved in the development of ovarian cancers and may represent a useful target for their detection and treatment.


Sujet(s)
Facteur nucléaire hépatocytaire HNF-1 bêta/biosynthèse , Facteur nucléaire hépatocytaire HNF-1 bêta/métabolisme , Tumeurs de l'ovaire/génétique , Séquence nucléotidique , Méthylation de l'ADN , Épigenèse génétique , Femelle , Tumeurs gastro-intestinales/génétique , Tumeurs gastro-intestinales/anatomopathologie , Analyse de profil d'expression de gènes , Humains , Données de séquences moléculaires , Tumeurs de l'ovaire/anatomopathologie , Cellules cancéreuses en culture
11.
Br J Dermatol ; 151(2): 472-80, 2004 Aug.
Article de Anglais | MEDLINE | ID: mdl-15327557

RÉSUMÉ

BACKGROUND: Anti-cancer effects of cyclooxygenase (COX)-2 inhibitors have been reported, but not fully investigated in skin and oral diseases. 5-aminolaevulinic acid (ALA)-based photodynamic therapy (PDT) for treating those patients with skin and oral lesions is a highly sophisticated procedure, but the incidence of disease recurrence after treatment is rather significant. OBJECTIVE: To confirm that COX-2 could be a molecular target in adjunctive therapy to ALA-based PDT, we investigated (i) COX-2 expression in various skin and oral diseases, and (ii) the inhibitory effects on cellular growth of COX-2 selective inhibitor (nimesulide), ALA-based PDT and their combination on human oral squamous cell carcinoma (SCC) cell lines. METHODS: A total of 129 biopsy samples from the skin and oral mucosal lesions were tested immunohistochemically for COX-2 expression. Then the in vitro effects of nimesulide, ALA-based PDT, and their combination were determined on two SCC cell lines, HSC-2 and HSC-4. Three different methods (MTT assay, double-staining for annexin V and propidium iodide, caspase-3/CPP32 fluorometric protease assay) were applied for evaluation of their inhibitory effects on these two cell lines. RESULTS: Among the skin diseases, a considerable number of COX-2 high expressers were found in actinic keratosis (15 of 25, 60%), Bowen's disease (13 of 17, 76%) and extramammary Paget's disease (15 of 15, 100%). In contrast, only one of 33 (3%) basal cell carcinoma tumours was a COX-2 high expresser. Among the oral mucosal biopsies, the proportion of COX-2 high expressers increased gradually from hyperplasia (one of six, 17%) through mild dysplasia (five of eight, 63%) and moderate dysplasia (20 of 23, 87%) to severe dysplasia (two of two, 100%). Nimesulide had an inhibitory effect in vitro on HSC-2 (proven to be a COX-2 high expresser), but not on HSC-4 (a COX-2 non-expresser). While ALA-based PDT showed an inhibitory effect on both HSC-2 and HSC-4, most importantly the combination of nimesulide and ALA-based PDT demonstrated a significant synergistic effect on the cellular growth inhibition of only HSC-2, but not of HSC-4. CONCLUSIONS: Our study strongly suggests that COX-2 can be one of the molecular targets in treating various skin and oral diseases. The results from our in vitro experiments also prompt us to develop a new protocol with a combination of COX-2 selective inhibitor and ALA-based PDT for more effective treatment of those diseases.


Sujet(s)
Inhibiteurs des cyclooxygénases/usage thérapeutique , Isoenzymes/antagonistes et inhibiteurs , Maladies de la bouche/traitement médicamenteux , Photothérapie dynamique/méthodes , Maladies de la peau/traitement médicamenteux , Sulfonamides/usage thérapeutique , Acide amino-lévulinique/usage thérapeutique , Maladie de Bowen/traitement médicamenteux , Maladie de Bowen/enzymologie , Carcinome épidermoïde/traitement médicamenteux , Carcinome épidermoïde/enzymologie , Division cellulaire/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Cyclooxygenase 2 , Inhibiteurs de la cyclooxygénase 2 , Synergie des médicaments , Association de médicaments , Humains , Immunohistochimie/méthodes , Isoenzymes/analyse , Kératose/traitement médicamenteux , Kératose/enzymologie , Protéines membranaires , Maladies de la bouche/enzymologie , Muqueuse de la bouche/enzymologie , Tumeurs de la bouche/traitement médicamenteux , Tumeurs de la bouche/enzymologie , Maladie de Paget extramammaire/traitement médicamenteux , Maladie de Paget extramammaire/enzymologie , Photosensibilisants/usage thérapeutique , Prostaglandin-endoperoxide synthases/analyse , Maladies de la peau/enzymologie
12.
Scand J Clin Lab Invest ; 64(3): 185-94, 2004.
Article de Anglais | MEDLINE | ID: mdl-15222628

RÉSUMÉ

Glycerol dehydrase is an enzyme that catalyzes dehydration of glycerol into beta-propionaldehyde. It requires 5'-deoxyadenosylcobalamin, one of the forms of vitamin B12, as a coenzyme. The enzyme is inactivated in vitro by all forms of vitamin B12 stoichiometrically. The objective of this study was to determine vitamin B12 content by utilizing the inactivation of the enzyme by vitamin B12. After various examinations, an excellent standard curve was obtained up to 1 pmol vitamin B12 using 14 mU of the enzyme per tube. Glycerol dehydrase does not respond to vitamin B12 if it is bound to haptocorrin, a vitamin B12-binding protein. This necessitates a procedure for extraction of vitamin B12 from samples before assay. The enzyme was less inactivated by 5'-deoxyadenosylcobalamin than any other form of vitamin B12. However, this did not matter because all forms of vitamin B12 were converted into cyanocobalamin during the extraction procedure cited above, which was performed in a buffer containing potassium cyanide.


Sujet(s)
Glycéraldéhyde/analogues et dérivés , Hydro-lyases/métabolisme , Vitamine B12/analogues et dérivés , Vitamine B12/analyse , Aldéhydes , Analyse de variance , Benzothiazoles , Cobamides/composition chimique , Cobamides/métabolisme , Activation enzymatique , Escherichia coli/enzymologie , Analyse d'aliment , Glycéraldéhyde/métabolisme , Glycérol/métabolisme , Hydrazones , Hydro-lyases/composition chimique , Hydro-lyases/isolement et purification , Hydroxocobalamine/composition chimique , Hydroxocobalamine/métabolisme , Klebsiella pneumoniae/enzymologie , Mesures de luminescence , Cyanure de potassium/composition chimique , Propane , Propanediol dehydratase/isolement et purification , Propanediol dehydratase/métabolisme , Liaison aux protéines , Valeurs de référence , Analyse de régression , Reproductibilité des résultats , Spectrophotométrie , Stéréoisomérie , Comprimés/composition chimique , Thiazoles/composition chimique , Transcobalamines/métabolisme , Vitamine B12/composition chimique , Vitamine B12/métabolisme
13.
J Cosmet Sci ; 55(2): 163-76, 2004.
Article de Anglais | MEDLINE | ID: mdl-15131728

RÉSUMÉ

The salivary film or the acquired pellicle is a protein film formed initially on the enamel surface of teeth. Such a film plays an important role in enamel protection, but is also an initial substructure for the formation of plaque and the cosmetically undesirable colored stain. The composition and the structure of the film are still essentially unknown because of the difficulty of its isolation for characterization. The purpose of this study was to investigate the effect of some metal cations on the salivary film or the pellicle formation, and also to clarify the mechanism of development. First, using infrared spectroscopy (IR) and X-ray photoelectron spectroscopy (XPS), the in situ-formed film in the mouth was confirmed to contain selectively adsorbed well-known proteins. Then, in vitro studies have demonstrated that Ca2+ ions enhance film formation at the initial stage in virtue of Ca bridging and, interestingly, that Mg2+ ions oppositely inhibit the formation. Furthermore, the quartz-crystal microbalance (QCM), utilized successfully for the first time to study the salivary film, has shown the possibility of an alternate accumulation mechanism by which the surface charges on the film are effectively reversed by the opposite charged proteins.


Sujet(s)
Durapatite/composition chimique , Métaux/composition chimique , Salive/composition chimique , Techniques in vitro
14.
J Am Coll Cardiol ; 38(5): 1539-45, 2001 Nov 01.
Article de Anglais | MEDLINE | ID: mdl-11691537

RÉSUMÉ

UNLABELLED: OBJECTIVES; We assessed the effects of long-term amlodipine administration in a diastolic heart failure (DHF) rat model with preserved systolic function as well as the relationship between changes in left ventricular (LV) myocardial stiffening and alterations in extracellular matrix. BACKGROUND: Although the effect of long-term administration of amlodipine has been shown to be disappointing in patients with systolic failure, the effect is unknown in those with DHF. METHODS: Dahl salt-sensitive rats fed a high-salt diet for seven weeks were divided into three groups: eight untreated rats (DHF group), eight rats given high-dose amlodipine (10 mg/kg/day; HDA group) and seven rats given low-dose amlodipine (1 mg/kg/day; LDA group). RESULTS: High-dose administration of amlodipine decreased systolic blood pressure and controlled excessive hypertrophy, without a decrease in the collagen content, and prevented the elevation of LV end-diastolic pressure at 19 weeks. Low-dose administration of amlodipine with subdeppressive effects did not control either hypertrophy or fibrosis; however, it prevented myocardial stiffening and, hence, the elevation of LV end-diastolic pressure. The ratio of type I to type III collagen messenger ribonucleic acid levels was significantly lower in both the HDA and LDA groups than in the DHF group. CONCLUSIONS: Long-term administration of amlodipine prevented the transition to DHF both at the depressor and subdepressor doses. Amlodipine did not decrease the collagen content, but attenuated myocardial stiffness, with inhibition of the phenotype shift from type III to type I collagen. Thus, amlodipine may exert beneficial effects through amelioration of collagen remodeling in the treatment of DHF.


Sujet(s)
Amlodipine/usage thérapeutique , Antihypertenseurs/usage thérapeutique , Inhibiteurs des canaux calciques/usage thérapeutique , Diastole/effets des médicaments et des substances chimiques , Modèles animaux de maladie humaine , Défaillance cardiaque/étiologie , Défaillance cardiaque/prévention et contrôle , Hypertension artérielle/complications , Hypertension artérielle/traitement médicamenteux , Amlodipine/pharmacologie , Analyse de variance , Animaux , Antihypertenseurs/pharmacologie , Inhibiteurs des canaux calciques/pharmacologie , Collagène/analyse , Collagène/génétique , Évolution de la maladie , Relation dose-effet des médicaments , Évaluation préclinique de médicament , Échocardiographie transoesophagienne , Défaillance cardiaque/diagnostic , Défaillance cardiaque/physiopathologie , Immunohistochimie , Méthode des moindres carrés , Modèles linéaires , Mâle , Myocarde/composition chimique , Phénotype , Répartition aléatoire , Rats , Rats de lignée Dahl , Débit systolique/effets des médicaments et des substances chimiques , Facteurs temps , Remodelage ventriculaire/effets des médicaments et des substances chimiques
15.
J Hypertens ; 19(10): 1905-12, 2001 Oct.
Article de Anglais | MEDLINE | ID: mdl-11593113

RÉSUMÉ

OBJECTIVES: Brain natriuretic peptide (BNP) is a strong predictor of left ventricular (LV) hypertrophy (LVH) and dysfunction. However, our recent studies suggested that LVH is not necessarily associated with enhanced production of BNP in hypertension. This study aimed to clarify the relation of the characteristics of hypertrophy with the degree of gene expression of BNP in the developmental process of hypertensive heart failure. METHODS: Serial changes in LV geometry, histology and atrial natriuretic peptide (ANP) and BNP mRNA levels, were assessed in a hypertensive heart failure model using Dahl salt-sensitive rats (n = 24). We further studied effects of alpha1-receptor antagonist (doxazosin: 1 mg/kg per day, n = 5) and angiotensin II type 1 receptor (AT1R) antagonist (candesartan cilexetil: 1 mg/kg per day, n = 5). RESULTS: The BNP mRNA level was not elevated at the compensatory hypertrophic stage when ANP mRNA level was elevated. BNP mRNA level was increased with further progression of hypertrophy and development of fibrosis. AT1R blockade prevented such fibrosis and further progression of hypertrophy with normalization of BNP mRNA levels. Compensatory hypertrophy was not suppressed; therefore, ANP mRNA level, although decreased, was still beyond the normal level. The alpha1-receptor blockade slightly attenuated LV hypertrophy with a slight decrease in ANP mRNA levels. LV fibrosis was not prevented, and the BNP mRNA level was not decreased. CONCLUSIONS: BNP gene expression is not enhanced by initial compensatory hypertrophy, but is enhanced by LV fibrosis and late stage progression of hypertrophy dependent on AT1R-mediated signaling pathway.


Sujet(s)
Bas débit cardiaque/étiologie , Bas débit cardiaque/physiopathologie , Hypertension artérielle/complications , Myocarde/métabolisme , Natriurétiques/biosynthèse , Remodelage ventriculaire , Animaux , Facteur atrial natriurétique/génétique , Bas débit cardiaque/anatomopathologie , Échocardiographie , Fibrose , Ventricules cardiaques , Hémodynamique , Mâle , Myocarde/anatomopathologie , Peptide natriurétique cérébral/génétique , ARN messager/métabolisme , Rats , Rats de lignée Dahl
16.
Auris Nasus Larynx ; 28 Suppl: S71-5, 2001 May.
Article de Anglais | MEDLINE | ID: mdl-11683348

RÉSUMÉ

We analyzed 143 cases of skull base surgery collected from the eight institutions of the Study Group supported by the Grant-in-Aid for Cancer Research from the Ministry of Health and Welfare of Japan. Histologically, the most common type was squamous cell carcinoma (n = 78), which was followed by olfactory neuroblastoma (n = 16) and adenoid cystic carcinoma (n = 16). The most frequent surgical approach was frontal craniotomy (n = 66), followed by front-temporal craniotomy (n = 54) and infratemporal fossa approach (n = 8). For repair of dura matter, fascia lata was used in 37 cases. galeopericranial flap in 35 and temporal muscle fascia in 16. The 5-year survival rate by Kaplan-Meier method of nose and paranasal sinus carcinoma (n = 119) was 48%. As for histological classification, the survival rates were both 65%) in adenoid cystic carcinoma (n = 12) and bone soft tissue malignancy (n = 10), 62% in olfactory neuroblastoma (n = 16), 46% in squamous cell carcinoma (n = 62) and 33% in adenocarcinoma (n = 11). All the three cases of malignant melanoma died within 1 year, so we considered skull base surgery to be contraindicated for this disease. Complications were observed in 62 out of the 143 cases (43%); local infection was most frequent in 29 cases. liquorrhea in 18, abscess in 16, necrosis of the flap and meningitis in ten cases, DIC in four, rupture of the internal carotid artery in two and cerebral thrombosis in one. Death caused directly by surgery was in ten cases (7%). It is important that a multi-center registry be maintained to have a large enough database for comparison of results, and prognosis for each histological entity and further define the role of multidisciplinary treatment.


Sujet(s)
Tumeurs de la tête et du cou/chirurgie , Tumeurs de la base du crâne/chirurgie , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Femelle , Humains , Japon , Mâle , Adulte d'âge moyen
17.
Mol Carcinog ; 31(3): 161-70, 2001 Jul.
Article de Anglais | MEDLINE | ID: mdl-11479925

RÉSUMÉ

Several new loci were identified by a comprehensive analysis of loss of heterozygosity (LOH) using a subtraction library between matched normal and renal cell carcinoma (RCC) tissues. A total of 187 clones from the library, with a complexity of 1x10(4), were mapped, and 44 clusters of the mapped loci were subjected to LOH analysis using microsatellite markers. A total of 27 loci, which exhibited frequencies of LOH of at least 10% among 44 tumors, mostly clear-cell RCC, included several loci that were reported previously, such as, the von Hippel-Lindau gene, adenomatous polyposis coli, and interferon regulatory factor-1, as well as new loci, at 5q32-q34, 6q21-q22, 8p12, and others. These loci exhibited LOH among 11.8-93.8% of tumors, and most, if not all, were derived from the sites of hemizygous deletions. The minimum regions of LOH of chromosomes 5, 6, and 8 were 9.0, 10.3, and 0.775 Mb, respectively. The average distance between the cloned fragments on the chromosomes was 2.2 Mb in 187 clones, indicating that the minimum LOH size expected from this subtraction analysis was roughly 50 kb. Therefore, the strategy described here provides comprehensive analysis of LOH sites, which were mostly caused by hemizygous deletions.


Sujet(s)
Néphrocarcinome/génétique , Néphrocarcinome/métabolisme , Délétion de gène , Banque de gènes , Tumeurs du rein/génétique , Tumeurs du rein/métabolisme , Perte d'hétérozygotie , Cartographie chromosomique , Chromosomes humains de la paire 3 , Chromosomes humains de la paire 5 , Chromosomes humains de la paire 6 , Chromosomes humains de la paire 8 , Clonage moléculaire , Marqueurs génétiques , Humains , Répétitions microsatellites , Modèles génétiques
19.
Masui ; 50(4): 419-21, 2001 Apr.
Article de Japonais | MEDLINE | ID: mdl-11345759

RÉSUMÉ

Sudden reduction in end-tidal PCO2 and SpO2 occurred during the endoscopic third ventriculostomy in a patient with hydrocephalus under general anesthesia. We suspect that it was caused by pulmonary air embolism. A 63-year-old female was scheduled for endoscopic third ventriculostomy under general anesthesia. Endoscopic manipulation caused hemorrhage from chorioid plexus 21 minutes after the procedure was begun, and intraventricular irrigation was performed to achieve hemostasis. In the subsequent 3 minutes, end-tidal PCO2 declined from 26 mmHg to 15 mmHg (PaCO2 39.6 mmHg), and SpO2 declined from 98% to 92% (PaO2 69.2 mmHg). Nitrous oxide was discontinued immediately because pulmonary air embolism was suspected and the oxygen concentration was increased to 100%. At the same time the surgical procedure was discontinued. After 15 minutes, end-tidal PCO2 recovered to 25 mmHg, and SpO2 recovered to 98% (PaO2 136.5 mmHg), and surgery was resumed. The patient recovered from anesthesia. The chest X-p at the end of operation, and pulmonary scintigraphy on the following day revealed no abnormal findings, but brain CT demonstrated a large quantity of air in both lateral ventricles.


Sujet(s)
Embolie gazeuse/étiologie , Endoscopie , Neurochirurgie/méthodes , Complications postopératoires , Embolie pulmonaire/étiologie , Femelle , Humains , Adulte d'âge moyen
20.
Neurosurgery ; 48(2): 328-32; discussion 322-3, 2001 Feb.
Article de Anglais | MEDLINE | ID: mdl-11220375

RÉSUMÉ

OBJECTIVE: We evaluated the effect of carotid endarterectomy on chronic ocular ischemic syndrome due to internal carotid artery stenosis by use of data obtained from ophthalmic artery color Doppler flow imaging. METHODS: We examined 11 patients with ocular ischemic syndrome due to internal carotid artery stenosis (>70% stenosis) who were being treated by carotid endarterectomy. Ophthalmic artery color Doppler flow imaging indicated ophthalmic artery flow direction and peak systolic flow velocity and was performed before and at 1 week, 1 month, and 3 months after surgery. RESULTS: We assessed the ophthalmic arteries of 11 patients via color Doppler flow imaging. Before undergoing carotid endarterectomy, five patients showed reversed ophthalmic artery flow. In the other six patients who experienced antegrade ophthalmic artery flow, the average peak systolic flow velocity was 0.09 +/- 0.05 m/s (mean +/- standard deviation). Preoperative reversed flow resolved in each patient 1 week after undergoing surgery. All patients showed antegrade ophthalmic artery flow. The average peak systolic flow velocity in the patients who had preoperative antegrade flow rose significantly, to 0.21 +/- 0.14 m/s (P < 0.05). There was no significant change as compared with findings at 1 week after surgery. During the follow-up period (mean, 32.4 mo), no patients complained of recurrent visual symptoms. At the end of the study period, visual acuity had improved in five patients and had not worsened in the other six patients. CONCLUSION: Carotid endarterectomy was effective for improving or preventing the progress of chronic ocular ischemia caused by internal carotid artery stenosis.


Sujet(s)
Artères carotides/chirurgie , Sténose carotidienne/complications , Sténose carotidienne/chirurgie , Endartériectomie , Oeil/vascularisation , Ischémie/étiologie , Ischémie/chirurgie , Angiographie , Vitesse du flux sanguin , Artère carotide interne , Maladie chronique , Fond de l'oeil , Humains , Ischémie/diagnostic , Ischémie/anatomopathologie , Ischémie/physiopathologie , Mâle , Adulte d'âge moyen , Artère ophtalmique/imagerie diagnostique , Artère ophtalmique/anatomopathologie , Artère ophtalmique/physiopathologie , Période postopératoire , Facteurs temps , Échographie-doppler couleur , Acuité visuelle
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