Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 20 de 1.031
Filtrer
1.
QJM ; 111(9): 635-641, 2018 Sep 01.
Article de Anglais | MEDLINE | ID: mdl-29939360

RÉSUMÉ

BACKGROUND: Although percutaneous endoscopic gastrostomy (PEG) is a well-accepted and less invasive method of feeding tube placement in patients with swallowing difficulties, complications and early death after PEG have been reported. AIM: This study aimed to evaluate predictive factors associated with 30-day mortality after PEG, and to assess the utility of nutritional supporting period before PEG in reducing early mortality following PEG. DESIGN: An observational study. METHODS: We retrospectively analyzed 268 patients who underwent PEG at Sapporo Shirakaba-dai Hospital from 2006 to 2010, using clinical and laboratory data to analyze predictive factors associated with early death after PEG. Then, we prospectively assessed 152 consecutive patients assessed for eligibility for PEG from 2011 to 2014. We assessed the patients' nutritional condition using Onodera's prognostic nutritional index (PNI), and supported nutrition for more than 10 days before PEG in patients with a poor nutritional index (PNI < 37). RESULTS: In both univariate and multivariate analyses in the retrospective study, Onodera's PNI of less than 37 was the only predictive factor for early mortality. In the second study, among the 115 patients who finally underwent PEG, early mortality rates improved to 1.7% from 5.2% in the first study. Conversely, 32% of patients with malnutrition who did not undergo PEG died within 30 days. CONCLUSION: Nutritional status might be a predictive factor for early mortality after PEG. In patients with poor nutritional status, nutritional supporting period before PEG might improve the outcomes and reduce unnecessary PEG.


Sujet(s)
Nutrition entérale , Gastroscopie , Gastrostomie/mortalité , Malnutrition/complications , Sujet âgé , Sujet âgé de 80 ans ou plus , Femelle , Gastrostomie/effets indésirables , Humains , Japon/épidémiologie , Mâle , Analyse multifactorielle , Évaluation de l'état nutritionnel , État nutritionnel , Pronostic , Études prospectives , Études rétrospectives , Analyse de survie , Facteurs temps
2.
Mucosal Immunol ; 11(3): 763-773, 2018 05.
Article de Anglais | MEDLINE | ID: mdl-29068000

RÉSUMÉ

Dectin-1 (gene symbol: Clec7a) is a receptor for ß-glucans that play an important role for the host defense against fungi. Recently, we showed that Clec7a-/- mice are resistant against dextran sodium sulfate (DSS)-induced colitis because of regulatory T-cell population expansion in the colon. The regulatory T-cell expansion is caused by expansion of commensal Lactobacillus murinus whose growth is suppressed by an antimicrobial protein, calprotectin S100A8/A9. In this report, we showed that S100A8 was mainly produced by mouse colonic epithelial cells. S100A8 was not induced directly by Dectin-1 but by Dectin-1-induced cytokines, especially interleukin-17F (IL-17F), that were produced by several types of innate immune cells including CD11c+/CD11b+ myeloid cells in colonic lamina propria. S100A8/A9 heterodimer preferentially suppressed the growth of L. murinus that was increased in both Clec7a-/- and Il17f-/- mice. Furthermore, similar expansion of L. murinus and DSS-colitis resistance were observed in mice fed with ß-glucan-free food. These observations suggest that food-derived ß-glucans control the specific commensal microbiota via the Dectin-1-IL-17F-calprotectin axis to maintain the intestinal homeostasis.


Sujet(s)
Colite/immunologie , Côlon/immunologie , Microbiome gastro-intestinal/physiologie , Muqueuse intestinale/physiologie , Lactobacillus/physiologie , Complexe antigénique L1 leucocytaire/métabolisme , Cellules myéloïdes/physiologie , bêta-Glucanes/administration et posologie , Animaux , Anti-infectieux/métabolisme , Calgranuline A/métabolisme , Colite/induit chimiquement , Colite/génétique , Aliments , Interactions hôte-microbes , Interleukine-17/génétique , Interleukine-17/métabolisme , Lectines de type C/génétique , Lectines de type C/métabolisme , Complexe antigénique L1 leucocytaire/génétique , Souris , Souris de lignée C57BL , Souris knockout , bêta-Glucanes/métabolisme
3.
Bone Marrow Transplant ; 52(7): 969-976, 2017 Jul.
Article de Anglais | MEDLINE | ID: mdl-28368379

RÉSUMÉ

Therapy-related acute myeloid leukemia and myelodysplastic syndrome (t-AML/MDS) represent severe late effects in patients receiving hematopoietic cell transplantation (HCT) for lymphoma. The choice between high-dose therapy with autologous HCT and allogeneic HCT with reduced-intensity conditioning remains controversial in patients with relapsed lymphoma. We retrospectively analyzed incidence and risk factors for the development of t-AML/MDS in lymphoma patients treated with autologous or allogeneic HCT. A total of 13 810 lymphoma patients who received autologous (n=9963) or allogeneic (n=3847) HCT between 1985 and 2012 were considered. At a median overall survival (OS) of 52 and 46 months in autologous and allogeneic HCT groups, respectively, lymphoma patients receiving autologous HCT (1.38% at 3 years after autologous HCT) had a significant risk for developing t-AML/MDS compared to allogeneic HCT (0.37% at 3 years after allogeneic HCT, P<0.001). Significant risk factors for the development of t-AML/MDS after autologous and allogeneic HCT were high-stage risk at HCT (P=0.04) or secondary malignancies (P<0.001) and receiving cord blood stem cell (P=0.03) or involved field radiotherapy (P=0.002), respectively. Strategies that carefully select lymphoma patients for autologous HCT, by excluding lymphoma patients with high-stage risk at HCT, may allow the identification of individual lymphoma patients at particular high risk for t-AML/MDS.


Sujet(s)
Transplantation de cellules souches hématopoïétiques , Leucémie aigüe myéloïde/épidémiologie , Lymphomes/épidémiologie , Lymphomes/thérapie , Syndromes myélodysplasiques/épidémiologie , Seconde tumeur primitive/épidémiologie , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Allogreffes , Autogreffes , Femelle , Études de suivi , Humains , Mâle , Adulte d'âge moyen , Facteurs de risque
4.
Br J Anaesth ; 117(1): 80-6, 2016 07.
Article de Anglais | MEDLINE | ID: mdl-27147542

RÉSUMÉ

BACKGROUND: Neonatal exposure to anaesthetics such as sevoflurane has been reported to result in behavioural deficits in rodents. However, while oxidative injury is thought to play an underlying pathological role, the mechanisms of neurotoxicity remain unclear. In the present study, we investigated whether the NADPH oxidase inhibitor apocynin protects against long-term memory impairment produced by neonatal sevoflurane exposure in mice. METHODS: Postnatal day six mice were divided into four groups; (1) non-anaesthesia, (2) intraperitoneal apocynin (50 mg kg(-1)) treatment, (3) 3% sevoflurane exposure for 6 h, and (4) apocynin treatment combined with sevoflurane exposure. Superoxide concentrations and NADPH oxidase expression in the brain were determined using dihydroethidium fluorescence and immunoblotting, respectively. Cleaved caspase-3 immunoblotting was used for the detection of apoptosis, and cytochrome c immunoblotting was performed to evaluate mitochondrial function. Long-term cognitive impairment was evaluated using the fear conditioning test in adulthood. RESULTS: Sevoflurane exposure increased concentrations of superoxide (109%) and the NADPH oxidase subunit p22phox (39%) in the brain, and apocynin abolished these increases. Neonatal sevoflurane exposure caused learning deficits in adulthood. Apocynin also maintained long-term memory function in mice given neonatal sevoflurane exposure, and it reduced apoptosis and decreased cytochrome c concentrations in the brains of these mice. CONCLUSIONS: Apocynin reduces neuronal apoptosis and protects against long-term memory impairment in mice, neonatally exposed to sevoflurane by reducing superoxide concentrations. These findings suggest that NADPH oxidase inhibitors may protect against cognitive dysfunction resulting from neonatal anaesthesia.


Sujet(s)
Animaux nouveau-nés , NADPH oxidase , Animaux , Mémoire à long terme , Éthers méthyliques , Souris , Souris de lignée C57BL , Sévoflurane
5.
J Investig Allergol Clin Immunol ; 25(3): 205-13, 2015.
Article de Anglais | MEDLINE | ID: mdl-26182687

RÉSUMÉ

BACKGROUND: X-linked lymphoproliferative syndrome type 2 is a rare hereditary immunodeficiency caused by mutations in the XIAP gene. This immunodeficiency frequently results in hemophagocytic lymphohistiocytosis, although hypogammaglobulinemia and dysgammaglobulinemia are also common. OBJECTIVE: We identified 17 patients from 12 Japanese families with mutations in XIAP. The Glu349del mutation was observed in 3 patients, each from a different family. Interestingly, these patients exhibited dysgammaglobulinemia but not hemophagocytic lymphohistiocytosis. We conducted an immunological study of patients carrying Glu349del and other mutations to elucidate the pathogenic mechanisms of dysgammaglobulinemia in patients with mutations in the XIAP gene. PATIENTS AND METHODS: We performed an immunological study of 2 patients carrying the Glu349del mutation and 8 patients with other mutations. RESULTS: Flow cytometry showed that the percentage of memory B cells in patients with a mutation in XIAP was lower than that observed in the healthy controls. The patients with the Glu349del mutation had a lower percentage of memory B cells than those with other mutations. Ig production was reduced in patients with the Glu349del mutation. Increased susceptibility to apoptosis was observed in the patients with other mutations. Susceptibility to apoptosis was normal in patients with Glu349del. Microarray analysis indicated that expression of Ig-related genes was reduced in patients with the Glu349del mutation and that the pattern was different from that observed in the healthy controls or patients with other mutations in XIAP. CONCLUSIONS: Patients carrying the Glu349del mutation in the XIAP gene may have a clinically and immunologically distinct phenotype from patients with other XIAP mutations. The Glu349del mutation may be associated with dysgammaglobulinemia.


Sujet(s)
Dysgammaglobulinémie/génétique , Maladies génétiques liées au chromosome X/génétique , Syndromes lymphoprolifératifs/génétique , Mutation , Protéine inhibitrice de l'apoptose liée au chromosome X/génétique , Adolescent , Apoptose , Asiatiques/génétique , Lymphocytes B/immunologie , Études cas-témoins , Cellules cultivées , Enfant , Enfant d'âge préscolaire , Analyse de mutations d'ADN , Dysgammaglobulinémie/diagnostic , Dysgammaglobulinémie/ethnologie , Dysgammaglobulinémie/immunologie , Femelle , Cytométrie en flux , Analyse de profil d'expression de gènes/méthodes , Maladies génétiques liées au chromosome X/diagnostic , Maladies génétiques liées au chromosome X/ethnologie , Maladies génétiques liées au chromosome X/immunologie , Prédisposition génétique à une maladie , Humains , Mémoire immunologique , Immunophénotypage/méthodes , Nourrisson , Japon , Syndromes lymphoprolifératifs/diagnostic , Syndromes lymphoprolifératifs/ethnologie , Syndromes lymphoprolifératifs/immunologie , Mâle , Séquençage par oligonucléotides en batterie , Pedigree , Phénotype , Lymphocytes T/immunologie , Lymphocytes T/anatomopathologie
6.
Gene Ther ; 22(3): 217-26, 2015 Mar.
Article de Anglais | MEDLINE | ID: mdl-25567536

RÉSUMÉ

The CD40/CD154 co-stimulatory pathway is crucial in alloimmune response. We developed a novel small interfering RNA (siRNA) delivery system with a poly-dA extension at the 5'-end of the siRNA sense strand that was stably incorporated into 1,3-ß-glucan (schizophyllan, SPG). This was captured and incorporated into dendritic cells (DCs) through its receptor, Dectin-1, specifically silencing CD40 genes (siCD40) to exert immunoregulatory activity. siCD40/SPG-treated CBA mice permanently accepted B10 fully mismatched cardiac allografts. Consistent with graft survival, the infiltration of CD4(+), CD8(+) T cells into the graft was lower, and that the numbers of CD40(low)CD11c(+) DCs cells and CD4(+)Foxp3(+)cells were increased in both the graft and in the recipient spleen. In addition, naive CBA recipients given an adoptive transfer of splenocytes from the primary recipients with siCD40/SPG accepted a heart graft from donor-type B10, but not third-party Balb/c mice. In conclusion, the treatment with siCD40/SPG targeting DCs could generate antigen-specific Tregs, resulting in the permanent acceptance of mouse cardiac allografts. These findings have important implications for clarifying the mechanism underlying the induction of tolerance in DCs, and also highlight the potential of immunomodulation and the feasibility of siRNA-based clinical therapy in the transplantation field.


Sujet(s)
Adjuvants immunologiques/métabolisme , Allogreffes/physiologie , Antigènes CD40/métabolisme , Transplantation cardiaque , Cellules myéloïdes/métabolisme , Petit ARN interférent/métabolisme , Schizophyllane/métabolisme , Adjuvants immunologiques/composition chimique , Allogreffes/cytologie , Animaux , Lymphocytes T CD4+/immunologie , Lymphocytes T CD8+/immunologie , Cellules cultivées , Cellules dendritiques/immunologie , Modèles animaux de maladie humaine , Mâle , Souris de lignée BALB C , Souris de lignée C57BL , Souris de lignée CBA , Petit ARN interférent/composition chimique , Petit ARN interférent/génétique , Schizophyllane/composition chimique , Sous-populations de lymphocytes T/immunologie , Transfection
7.
J. investig. allergol. clin. immunol ; 25(3): 205-213, 2015. tab, ilus
Article de Anglais | IBECS | ID: ibc-136426

RÉSUMÉ

Antecedentes: El síndrome linfoproliferativo ligado al cromosoma X (XLP) tipo 2, está causado por la mutación del gen XIAP. Se trata de una inmunodeficiencia hereditaria rara. Frecuentemente, los pacientes con XLP2 padecen linfohistiocitosis hemofagocítica (HLH) y disgammaglobulinemia. Objetivo: Se han evaluado diecisiete pacientes japoneses, provenientes de doce familias con mutaciones XIAP y tres pacientes con la mutación Glu349del. Curiosamente, estos últimos pacientes desarrollaron una disgammaglobulinemia pero no HLH. Para dilucidar el fondo patogénico de la disgammaglobulinemia en pacientes con mutación del gen XIAP , se llevó a cabo un estudio inmunológico de estos pacientes. Pacientes y métodos: Pudieron concluir el estudio inmunológico dos pacientes con la mutación Glu349del y ocho pacientes con otras mutaciones. Resultados: Mediante análisis de citometría de flujo se observó que la proporción de linfocitos B de memoria en los pacientes con la mutación XIAP fue menor que la observada en los controles. Los pacientes con la mutación Glu349del tuvieron una menor proporción de linfocitos B de memoria que aquellos con otras mutaciones. Los pacientes con la mutación Glu349del presentaron menor producción de inmunoglobulinas. Los pacientes con la mutación Glu349del mostraron una susceptibilidad normal a la apoptosis, mientras que en los portadores de otras mutaciones se observó una mayor susceptibilidad a la muerte celular. El análisis de microarray indicó que los pacientes con la mutación Glu349del tenían disminuida la expresión de genes relacionados con las inmunoglobulinas y un patrón diferente de la observada en los controles normales o en pacientes con otras mutaciones de genes de XIAP. Conclusiones: Los pacientes portadores de la mutación en el gen Glu349 del XIAP pueden tener un fenotipo clínicamente e inmunológicamente diferente que los pacientes con otras mutaciones XIAP . La mutación Glu349del puede estar asociada con disgammaglobulinemia (AU)


Background: X-linked lymphoproliferative syndrome type 2 is a rare hereditary immunodeficiency caused by mutations in the XIAP gene. This immunodeficiency frequently results in hemophagocytic lymphohistiocytosis, although hypogammaglobulinemia and dysgammaglobulinemia are also common. Objective: We identified 17 patients from 12 Japanese families with mutations in XIAP . The Glu349del mutation was observed in 3 patients, each from a different family. Interestingly, these patients exhibited dysgammaglobulinemia but not hemophagocytic lymphohistiocytosis. We conducted an immunological study of patients carrying Glu349del and other mutations to elucidate the pathogenic mechanisms of dysgammaglobulinemia in patients with mutations in the XIAP gene. Patients and Methods: We performed an immunological study of 2 patients carrying the Glu349del mutation and 8 patients with other mutations. Results: Flow cytometry showed that the percentage of memory B cells in patients with a mutation in XIAP was lower than that observed in the healthy controls. The patients with the Glu349del mutation had a lower percentage of memory B cells than those with other mutations. Ig production was reduced in patients with the Glu349del mutation. Increased susceptibility to apoptosis was observed in the patients with other mutations. Susceptibility to apoptosis was normal in patients with Glu349del. Microarray analysis indicated that expression of Ig-related genes was reduced in patients with the Glu349del mutation and that the pattern was different from that observed in the healthy controls or patients with other mutations in XIAP. Conclusions: Patients carrying the Glu349del mutation in the XIAP gene may have a clinically and immunologically distinct phenotype from patients with other XIAP mutations. The Glu349del mutation may be associated with dysgammaglobulinemia (AU)


Sujet(s)
Humains , Mâle , Femelle , Syndromes lymphoprolifératifs/immunologie , Syndrome lymphoprolifératif avec auto-immunité/génétique , Syndrome lymphoprolifératif avec auto-immunité/immunologie , Lymphohistiocytose hémophagocytaire/génétique , Lymphohistiocytose hémophagocytaire/immunologie , Anticorps monoclonaux/analyse , Mutation/génétique , Dysgammaglobulinémie/génétique , Dysgammaglobulinémie/immunologie , Cytométrie en flux/instrumentation , Cytométrie en flux , Immunoglobulines/analyse , Immunoglobulines/immunologie
8.
Cancer Gene Ther ; 21(10): 427-33, 2014 Oct.
Article de Anglais | MEDLINE | ID: mdl-25213663

RÉSUMÉ

Increased expression of sialyl Lewis(x/a) carbohydrates, ligands for E-selectin, correlates with clinically advanced stages and metastasis of gastric and colon cancers. In contrast, Sd(a) carbohydrate is abundantly detected in the normal gastrointestinal mucosa but dramatically reduced or lost in cancer tissues. A glycosyltransferase, ß1,4N-acetylgalactosaminyltransferase 2 (B4GALNT2) that catalyzes Sd(a) carbohydrate synthesis, is silenced in cancer. In the present study, we aimed at reducing the expression of sialyl Lewis(x/a) of cancer cells in vivo by forced expression of B4GALNT2 and Sd(a), thereby preventing dissemination/metastasis, especially metastasis triggered by surgical maneuvers. We used a fiber-modified adenovirus (Ad) vector that contained a chimeric construct with a serotype 5 shaft and a serotype 3 knob. Using this Ad5/3 vector, we successfully introduced the B4GALNT2 gene into a human gastric cancer cell line KATO III in vitro and confirmed replacement of sialyl Lewis(x) to Sd(a) with a decrease in E-selectin-dependent adhesion. Administration of Ad5/3-B4GALNT2 vectors into the peritoneal cavity of mice after inoculation of KATO III cells with laparotomy significantly reduced the incidence of metastasis. Our results indicate that the transfer of a single gene encoding B4GALNT2 modified carbohydrate chains of cancer cells in vivo and decreased tumor dissemination and metastasis.


Sujet(s)
Adenoviridae/génétique , Techniques de transfert de gènes , Vecteurs génétiques/génétique , Glycosyltransferase/génétique , Tumeurs de l'estomac/génétique , Tumeurs de l'estomac/anatomopathologie , Animaux , Protéines de capside/génétique , Adhérence cellulaire/génétique , Lignée cellulaire tumorale , Modèles animaux de maladie humaine , Sélectine E/métabolisme , Activation enzymatique , Expression des gènes , Glycosyltransferase/métabolisme , Humains , Mâle , Souris , Métastase tumorale , Péritoine/anatomopathologie , Tumeurs de l'estomac/métabolisme , Transduction génétique , Tests d'activité antitumorale sur modèle de xénogreffe
10.
Clin Exp Immunol ; 177(1): 161-7, 2014 Jul.
Article de Anglais | MEDLINE | ID: mdl-24635107

RÉSUMÉ

Kawasaki disease (KD) is an acute vasculitis syndrome of unknown aetiology in children. The administration of Candida cell wall antigens induced KD-like coronary vasculitis in mice. However, the responses of KD patients to Candida cell wall antigen are unknown. In this study, we examined the response of KD patients to ß-glucan (BG), one of the major fungal cell wall antigens, by measuring the anti-BG titre. In KD patients, the anti-C. albicans cell wall BG titre was higher than that in normal children. The anti-BG titre was also higher in KD patients compared to children who served as control subjects. The efficacy of intravenous immunoglobulin (IVIG) therapy in KD is well established. We categorized the KD patients into three groups according to the therapeutic efficacy of intravenous immunoglobulin (IVIG) and compared the anti-BG titre among these groups. Anti-BG titres were similar in the control group and the non-responsive group. In the fully responsive group, the anti-BG titre showed higher values than those in the normal children. This study demonstrated clinically that KD patients have high antibody titres to Candida cell wall BG, and suggested the involvement of Candida cell wall BG in the pathogenesis of KD. The relationship between IVIG therapy and anti-BG titre was also shown. These results provide valuable insights into the therapy and diagnosis of KD.


Sujet(s)
Anticorps antifongiques/immunologie , Candida albicans/immunologie , Paroi cellulaire/immunologie , Maladie de Kawasaki/diagnostic , bêta-Glucanes/immunologie , Anticorps antifongiques/sang , Marqueurs biologiques/sang , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Immunoglobulines par voie veineuse/usage thérapeutique , Mâle , Maladie de Kawasaki/thérapie , Pronostic
11.
Int J Obes (Lond) ; 38(11): 1432-9, 2014 Nov.
Article de Anglais | MEDLINE | ID: mdl-24566854

RÉSUMÉ

BACKGROUND: Chronic inflammation in adipose tissue together with obesity induces insulin resistance. Inhibitors of chronic inflammation in adipose tissue can be a potent candidate for the treatment of diabetes; however, only a few compounds have been discovered so far. The objective of this study was to find a novel inhibitor that can suppress the inflammatory response in adipose tissue and to elucidate the intracellular signaling mechanisms of the compound. METHODS: To find the active compounds, we established an assay system to evaluate the inhibition of induced MCP-1 production in adipocyte/macrophage coculture in a plant extract library. The active compound was isolated by performing high-performance liquid chromatography (HPLC) and was determined as 4ß-hydroxywithanolide E (4ßHWE) by nuclear magnetic resonance (NMR) and mass spectroscopy (MS) spectral analyses. The effect of 4ßHWE on inflammation in adipose tissue was assessed with adipocyte culture and db/db mice. RESULTS: During the screening process, Physalis pruinosa calyx extract was found to inhibit production of MCP-1 in coculture strongly. 4ßHWE belongs to the withanolide family of compounds, and it has the strongest MCP-1 production inhibitory effect and lowest toxicity than any other withanolides in coculture. Its anti-inflammatory effect was partially dependent on the attenuation of NF-κB signaling in adipocyte. Moreover, in vivo experiments showed that the oral administration of 4ßHWE to db/db mice resulted in the inhibition of macrophage invasion and cytokine expression in adipose tissue after 2 weeks of treatment; improved the plasma adiponectin, non-esterified fatty acids and MCP-1 concentrations; and increased glucose tolerance after 3 to 4 weeks of treatment. CONCLUSIONS: These results suggest that 4ßHWE has anti-inflammatory effect via inhibition of NF-κB activation in adipocyte. Moreover, the attenuation of inflammation in adipocyte has an effect on the inhibition of macrophage accumulation in obese adipose tissue. Consequently, 4ßHWE improves impaired glucose tolerance. Thus, 4ßHWE is a useful natural anti-inflammatory compound to attenuate progression of diabetes and obesity.


Sujet(s)
Adipocytes/effets des médicaments et des substances chimiques , Tissu adipeux/anatomopathologie , Chimiokine CCL2/antagonistes et inhibiteurs , Inflammation/traitement médicamenteux , Macrophages/effets des médicaments et des substances chimiques , Facteur de transcription NF-kappa B/antagonistes et inhibiteurs , Facteur de transcription NF-kappa B/métabolisme , Physalis/composition chimique , Extraits de plantes/pharmacologie , Transduction du signal/effets des médicaments et des substances chimiques , Withanolides/pharmacologie , Cellules 3T3-L1 , Adipocytes/métabolisme , Adipocytes/anatomopathologie , Tissu adipeux/effets des médicaments et des substances chimiques , Tissu adipeux/métabolisme , Animaux , Chimiokine CCL2/biosynthèse , Chromatographie en phase liquide à haute performance , Techniques de coculture , Glucose/métabolisme , Immunotransfert , Insulinorésistance , Macrophages/métabolisme , Mâle , Spectrométrie de masse , Souris , Souris de lignée NOD/métabolisme , Résonance magnétique nucléaire biomoléculaire , Phytothérapie , Withanolides/isolement et purification
13.
J Colloid Interface Sci ; 407: 109-15, 2013 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-23830284

RÉSUMÉ

We have investigated the electrokinetic responses of two different kinds of clay particles, kaolinite and montmorillonite. The dielectric permittivity of kaolinite suspensions is linearly proportional to volume fraction up to volume fractions of 20%, whereas that of montmorillonite is deviating from a linear relationship, for volume fractions below 0.5%. This indicates that the montmorillonite particles experience a particle-particle interaction at these low volume fractions. The complex dipole coefficients of both clays estimated by experimental data are, however, within experimental error in good approximation independent on volume fraction and agree with the theoretical predictions. The relaxation frequency in clay-water system at low ionic strength is almost determined by the relaxation of the double layer for both kaolinite and montmorillonite. For volume fractions larger than 0.5% for montmorillonite, we find that the zeta potential measured by electroacoustic methods starts to depend strongly on volume fraction. It is expected that for these high volume fractions, the dipole coefficients will also become volume-fraction dependent.

14.
J Colloid Interface Sci ; 404: 72-9, 2013 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-23684223

RÉSUMÉ

Montmorillonite is a sheet-like clay mineral. The surface charge of the faces is always negative, whereas the surface charges of the edges depend on pH. In this study, pH is around 6.5 implying that the edges are slightly positive; however, the overall charge of the particle appears to be negative as the surface of the faces is 50 times larger than the edges. In the presence of an applied electric field, montmorillonite particles and their double layer will polarize. This polarization affects the electrokinetic response of the particles. In this article, we investigated the effect of ionic strength on the electrokinetic response of montmorillonite particles using the dielectric spectroscopy and electrophoretic mobility. The experimental dipole coefficient found by dielectric spectroscopy was compared to the semi-analytical formula presented by Chassagne [C. Chassagne, J. Colloid Interface Sci. 326 (2008)]. The amplitude of the dipole coefficient of montmorillonite particles increased and the relaxation frequency shifted to lower frequencies with decreasing ionic strength. This tendency is in qualitative agreement with the theoretical prediction. A better agreement between the experimental and theoretical amplitudes of the dipole coefficient and between the high-frequency experimental and theoretical mobilities was obtained when a Stern layer conductivity is introduced. The same values for the zeta potential and Stern layer conductivities were used in both measurement sets. The relaxation frequencies were not changed by addition of a Stern layer. This discrepancy between experimental and theoretical relaxation frequencies are due to the limitation of the theory that is not valid at low κa, as discussed in the conclusion.

15.
Allergy ; 68(6): 757-63, 2013 Jun.
Article de Anglais | MEDLINE | ID: mdl-23621581

RÉSUMÉ

BACKGROUND: Patients allergic to pollen have been known to become more symptomatic during pollen season compared with the nonpollen season. However, there are few studies regarding whether higher exposure to pollen might increase the prevalence of allergic diseases. METHODS: An ecological analysis was conducted to evaluate whether pollen exposure is associated with the prevalence of allergic diseases in schoolchildren. Pollen count data of Japanese cedar (Cryptomeria japonica) and Japanese cypress (Chamaecyparis obtusa), which are the major pollen allergens in Japan, were obtained from each prefecture. The prevalence of allergic diseases in schoolchildren in each prefecture was based on a nationwide cross-sectional survey using the International Study of Asthma and Allergies in Childhood questionnaire. RESULTS: After omitting three prefectures where pollen data were not available, data of 44 prefectures were analysed. The prevalence of allergic rhinoconjunctivitis in children aged 6-7 years was positively associated with both cedar and cypress pollen counts (P = 0.01, both), whereas the prevalence of allergic rhinoconjunctivitis in children aged 13-14 years was positively associated with only cypress pollen counts (P = 0.003). Furthermore, the prevalence of asthma was positively associated with cedar pollen counts in 6- to 7-year-old children (P = 0.003) but not cypress pollen counts in either age group. CONCLUSIONS: There are ecological associations between pollen counts and the prevalence of allergic diseases in Japanese schoolchildren. Further studies are needed to determine whether the difference between the effects of cedar and cypress pollens is attributable to pollen counts or allergenicity.


Sujet(s)
Allergènes/effets indésirables , Chamaecyparis/effets indésirables , Cryptomeria/effets indésirables , Exposition environnementale/statistiques et données numériques , Hypersensibilité immédiate/étiologie , Pollen/effets indésirables , Adolescent , Allergènes/analyse , Asthme/épidémiologie , Asthme/étiologie , Enfant , Conjonctivite allergique/épidémiologie , Conjonctivite allergique/étiologie , Études transversales , Exposition environnementale/effets indésirables , Exposition environnementale/analyse , Femelle , Enquêtes de santé , Humains , Hypersensibilité immédiate/épidémiologie , Japon/épidémiologie , Mâle , Analyse multifactorielle , Prévalence , Analyse de régression , Rhinite allergique saisonnière/épidémiologie , Rhinite allergique saisonnière/étiologie , Enquêtes et questionnaires
16.
Sci Technol Adv Mater ; 14(1): 014208, 2013 Feb.
Article de Anglais | MEDLINE | ID: mdl-27877556

RÉSUMÉ

In this paper we discuss the microstructure of lath martensitic steels and the mechanisms by which it controls cleavage fracture. The specific experimental example is a 9Ni (9 wt% Ni) steel annealed to have a large prior austenite grain size, then examined and tested in the as-quenched condition to produce a relatively coarse lath martensite. The microstructure is shown to approximate the recently identified 'classic' lath martensite structure: prior austenite grains are divided into packets, packets are subdivided into blocks, and blocks contain interleaved laths whose variants are the two Kurjumov-Sachs relations that share the same Bain axis of the transformation. When the steel is fractured in brittle cleavage, the laths in the block share {100} cleavage planes and cleave as a unit. However, cleavage cracks deflect or blunt at the boundaries between blocks with different Bain axes. It follows that, as predicted, the block size governs the effective grain size for cleavage.

19.
Transplant Proc ; 44(4): 1107-9, 2012 May.
Article de Anglais | MEDLINE | ID: mdl-22564637

RÉSUMÉ

AIM: To investigate whether mouse bone marrow mesenchymal stem cells (BMC) stimulate liver regeneration after partial hepatectomy. METHODS: Isolated BMCs were purified by density gradient centrifugation. We performed a 70% hepatectomy in male BALB/c mice followed by injection of BMCs into the portal vein (PV-BMC group), or the tail vein (IV-BMC group), or of saline into the portal vein (control group). RESULTS: The wet weight of the liver remnant increased significantly in the PV-BMC group at 3 and 5 days after hepatectomy compared with the IV-BMC and control groups. The Ki-67 labeling index revealed that the increase to result from stimulation of DNA synthesis. The constitutive interleukin-6 and hepatocyte growth factor mRNAs in the remnant liver tended to increase in the PV-BMC group at 3 days after hepatectomy. CONCLUSIONS: These results demonstrated that BMC injection into the portal vein enhanced liver growth after partial hepatectomy in mice.


Sujet(s)
Transplantation de moelle osseuse , Hépatectomie , Régénération hépatique , Foie/chirurgie , Transplantation de cellules souches mésenchymateuses , Veine porte , Animaux , Prolifération cellulaire , Réplication de l'ADN , Facteur de croissance des hépatocytes/génétique , Injections veineuses , Interleukine-6/génétique , Antigène KI-67/métabolisme , Foie/vascularisation , Foie/métabolisme , Foie/anatomopathologie , Foie/physiopathologie , Mâle , Souris , Souris de lignée BALB C , Souris de lignée C57BL , ARN messager/métabolisme , Facteurs temps , Régulation positive
20.
Med Phys ; 39(6Part11): 3732, 2012 Jun.
Article de Anglais | MEDLINE | ID: mdl-28517145

RÉSUMÉ

PURPOSE: Gafchromic film for quantitative analysis was renewed from EBT2 to EBT3 film in November 2011. The purpose of this study is to investigate the relevant characteristics of EBT3 film for its application in dosimetric verification for IMRT/VMAT or proton therapy. METHOD: We investigated the characteristics of EBT3 film with comparison of previous EBT2 film. The experiments in this study composed two categories. At first, the photo spectroscopy for the irradiated film was compared between EBT2 and EBT3. The film 1 day after the irradiation was analyzed by a photo spectrometer (SR520: JASCO Corporation, Japan). Secondly, we investigated several calibration curves which obtained by same batch. The films were calibrated by irradiation the films to 13 dose steps. The irradiated films were scanned by a flatbed scanner (ES-10000XL, Epson-Seiko Corporation, Japan). The difference on scan orientation was evaluated alternate portrait and landscape directions. The photon and proton beams were delivered from Clinac 21EX (Varian) and Mitsubishi machine, respectively. RESULTS: The peak absorption wavelength of EBT3 film and its response at all active range were basically same with that of EBT2 film. The peak wavelength of photo absorption in EBT3 was observed at 585 and 634 nm. The fog optical density was increased due to the hazy matte polyester for active layer. However, there is no change the tendency of the calibration curve responding to megavoltage photon and proton beams. The scan orientation dependency of EBT3 film was observed with similar to EBT2 film. The optical density of portrait orientation was 10% higher than that of landscape orientation. CONCLUSION: The dosimetric characteristics of EBT3 film were basically same with EBT2 film. With regard to the matte polyester, the creation of Newton's rings during scanning procedure was reduced. However, the suitable scan protocol should be used for accurate film dosimetry.

SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE
...