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1.
Nagoya J Med Sci ; 83(1): 107-111, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33727742

RESUMEN

Early detection of diseases is critical in infants. This study evaluates the usefulness of web searches in predicting diseases in order to encourage guardians to consult a doctor promptly if their children are ill. We collected six months of search queries from Yahoo! JAPAN Search between October 2016 and March 2017. Using a machine learning model, we investigated the accuracy of the search query's ability to predict the diagnosis of biliary atresia and hypertrophic pyloric stenosis. Both diseases were modeled with an accuracy of approximately 80%, and symptoms related to the disease were significant features in the model. These findings suggest the possibility of detecting diseases from web search queries performed by guardians. Through future research, we intend to propose a method that uses web search queries for early detection of these diseases by providing appropriate and timely information to support the guardians of patients.


Asunto(s)
Atresia Biliar/diagnóstico , Estenosis Hipertrófica del Piloro/diagnóstico , Motor de Búsqueda/estadística & datos numéricos , Diagnóstico Precoz , Humanos , Lactante , Recién Nacido , Internet , Japón , Aprendizaje Automático , Evaluación de Síntomas
2.
Clin J Gastroenterol ; 13(6): 1233-1238, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32656649

RESUMEN

The hepatitis C virus (HCV) NS5A-P32 deletion (P32del) confers potent resistance to NS5A inhibitors. Chronic hepatitis C patients in whom NS5A-P32del variants had emerged during prior direct-acting antiviral (DAA) therapy with an NS5A inhibitor show poor response to DAA retreatment. Here, we report three patients with HCV NS5A-P32del infection who were treated with sofosbuvir, velpatasvir plus ribavirin (SOF/VEL + RBV) in a real-world setting. The patients developed HCV NS5A-P32del, L31F + P32del, or L31V + P32del variants following failure of daclatasvir plus asunaprevir (DCV/ASV) therapy. One of the patients failed to respond to subsequent DCV/ASV and beclabuvir therapy, and the remaining two patients failed to respond to subsequent glecaprevir and pibrentasvir therapy. All three patients completed 24-week SOF/VEL + RBV therapy. Serum HCV RNA became negative at the end of the therapy in all three patients. Two patients with NS5A-P32del and NS5A-L31F + P32del achieved sustained virological response 12 weeks after completion of treatment (SVR12), but HCV relapsed in the remaining NS5A-L13V + P32del patient. Direct sequence analysis detected no additional variants within either the NS5A or NS5B regions at the time of relapse. In conclusion, three patients with prior NS5A-P32del-associated DAA treatment failure received 24 weeks of SOF/VEL + RBV therapy, and two of the patients achieved SVR12.


Asunto(s)
Hepatitis C Crónica , Hepatitis C , Antivirales/uso terapéutico , Carbamatos , Quimioterapia Combinada , Genotipo , Hepacivirus/genética , Hepatitis C/tratamiento farmacológico , Hepatitis C Crónica/tratamiento farmacológico , Compuestos Heterocíclicos de 4 o más Anillos , Humanos , Ribavirina/uso terapéutico , Sofosbuvir/uso terapéutico , Resultado del Tratamiento
3.
Cancer Lett ; 240(1): 102-13, 2006 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-16246485

RESUMEN

Recently there has been a shift in the prevailing paradigm regarding the dose dependence of carcinogen action with increasing acceptance of hormesis phenomenon, although underlying mechanisms remain to be established. To ascertain whether alpha-benzene hexachloride (alpha-BHC) might act by hormesis, rats were initiated with diethylnitrosamine and then alpha-BHC ranging from 0.01 to 500 ppm was administered in the diet for 10 weeks. The highest concentration of alpha-BHC significantly increased the number and area of glutathione S-transferase placental form (GST-P) positive foci, preneoplastic lesions in the liver, but its low dose, 0.05 ppm, caused significant reduction, showing a J-shape dose-response curve. The proliferating cell nuclear antigen positive index for GST-P positive foci in the low dose-treated group was significantly reduced. The dose response curves of CYP450 content, NADPH-P450 reductase activity and 8-hydroxydeoxyguanosine formation revealed the same pattern as GST-P positive foci data. The response curves of CYP2B1 and 3A2 in their activities, protein and mRNA expression showed a threshold but CYP2C11 activity exhibited an inverted J-shape. These results might suggest the possibility of hormesis of alpha-BHC at early stages of rat hepatocarcinogenesis. The possible mechanism involves induction of detoxifying enzymes at low dose, influencing free radical production and oxidative stress, and consequently pathological change in the liver.


Asunto(s)
Hexaclorociclohexano/toxicidad , Insecticidas/toxicidad , Neoplasias Hepáticas Experimentales/inducido químicamente , Hígado/efectos de los fármacos , Lesiones Precancerosas/inducido químicamente , 8-Hidroxi-2'-Desoxicoguanosina/análogos & derivados , Animales , Hidrocarburo de Aril Hidroxilasas/genética , Hidrocarburo de Aril Hidroxilasas/metabolismo , Proliferación Celular , Citocromo P-450 CYP2B1/genética , Citocromo P-450 CYP2B1/metabolismo , Citocromo P-450 CYP3A , Daño del ADN , Dietilnitrosamina , Relación Dosis-Respuesta a Droga , Gutatión-S-Transferasa pi/análisis , Gutatión-S-Transferasa pi/metabolismo , Guanina/análogos & derivados , Guanina/análisis , Hígado/enzimología , Hígado/patología , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/prevención & control , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , NADPH-Ferrihemoproteína Reductasa/metabolismo , Lesiones Precancerosas/metabolismo , Lesiones Precancerosas/prevención & control , Antígeno Nuclear de Célula en Proliferación/análisis , Antígeno Nuclear de Célula en Proliferación/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas F344 , Testosterona/metabolismo
4.
Toxicol Pathol ; 33(3): 329-35, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15814362

RESUMEN

This study was carried out to achieve pathological understanding for the persistence of cirrhosis induced by thioacetamide (TAA). Forty-five, male,21-day-old, F344 rats were randomly allocated to group I and received drinking water as a control, and groups 2 and 3 given 0.015% or 0.03%TAA, respectively for 12 weeks. Two-third of animals per group were sacrificed, and remainder were maintained for a further 4 weeks without TAA treatment. Liver cirrhosis was induced in all animals in group 3 at week 12, with obvious increase of collagen content, and this persisted after cessation of TAA. Proliferating cell nuclear antigen (PCNA) positive labeling indices of nonparenchymal cells were increased significantly after cessation in groups 2 and 3 (p < 0.01). RT-RCR analysis of a-smooth muscle actin (alpha-SMA) showed significant increase in group 3 compared to that of control at both time points (p < 0.05). Immunohistochemical staining of it demonstrated positive cells to mainly be located around regenerating hepatic nodules at week 12, however, they were focused into enlarged portal areas consisting of fibrous tissues and pseudo-bile ductular cells after the cessation. Taken together, we conclude persistence of liver cirrhosis could be associated with the proliferation of nonparenchymal cells and altered location of alpha-SMA positive cells.


Asunto(s)
Actinas/análisis , Proliferación Celular , Desoxiguanosina/análogos & derivados , Cirrosis Hepática Experimental/patología , Músculo Liso/metabolismo , Miocitos del Músculo Liso/fisiología , 8-Hidroxi-2'-Desoxicoguanosina , Actinas/genética , Animales , Colágeno/análisis , Desoxiguanosina/análisis , Marcadores Genéticos/efectos de los fármacos , Glutatión Transferasa/análisis , Inmunohistoquímica , Masculino , Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Antígeno Nuclear de Célula en Proliferación/análisis , Ratas , Ratas Endogámicas F344 , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tioacetamida
5.
Toxicol Sci ; 75(2): 279-88, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12857943

RESUMEN

Long-term exposure of rodents to propylene oxide (PO) induced inflammation, respiratory cell hyperplasia, and nasal tumors at concentrations >/= 300 ppm, suggesting a possible role for cytotoxicity and compensatory cell proliferation in PO carcinogenesis. In this study, the effects of PO exposure on histopathology and cell proliferation in nasal and hepatic tissues were studied in male F344 rats exposed by inhalation for 3 or 20 days (0, 5, 25, 50, 300, and 500 ppm). Histopathology revealed an increase in mucous cell hyperplasia in the anterior nasal passages after 20 days of exposure (>/=300 ppm). This was associated with the formation of goblet cell nests. Cell proliferation was measured in the respiratory epithelium (NRE; mucociliary and transitional) lining the anterior nasal passages, the nasopharyngeal meatus (NPM), and the liver using BrdU administered with 3-day osmotic pumps. Significant increases in cell proliferation occurred (>3.6-fold) in the mucociliary epithelium lining the anterior nasal cavity at and above 300 ppm for both exposure periods. In the mucociliary epithelium, the 20-day labeling was commonly associated with nests of goblet cells. Significant increases in cell proliferation (>2.3-fold) were observed in the transitional epithelium at 500 ppm after 3 days of exposure and at 300 and 500 ppm after 20 days of exposure. Significant increases in cell proliferation in the NPM (>2.8-fold) were evident at 500 ppm PO after 3 days and at 300 and 500 ppm PO after 20 days of exposure. No exposure-related changes in cell proliferation were observed in the liver. These studies demonstrate a clear concordance between the site and exposure concentration for tumor induction and those causing significant increases in cell proliferation in the rat nose.


Asunto(s)
Carcinógenos/toxicidad , Compuestos Epoxi/toxicidad , Células Caliciformes/efectos de los fármacos , Administración por Inhalación , Animales , Bromodesoxiuridina/metabolismo , Carcinógenos/administración & dosificación , División Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Compuestos Epoxi/administración & dosificación , Células Caliciformes/metabolismo , Células Caliciformes/patología , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Ratas , Ratas Endogámicas F344
6.
Carcinogenesis ; 24(6): 1133-41, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12807746

RESUMEN

The primary purpose of this research is to examine the hypothesis that reactive oxygen species generated by estrogen quinonoids are the main source for the formation of aldehydic DNA lesions (ADL) in genomic DNA. ADL induced by quinonoid metabolites of 17beta-estradiol (E2), e.g. 4-hydroxyestradiol (4-OH-E2), 2-hydroxyestradiol (2-OH-E2), estrogen-3,4-quinones (E2-3,4-Q) and estrogen- 2,3-quinone (E2-2,3-Q), were investigated in calf thymus DNA (CT-DNA) under physiological conditions. The abasic sites resulting from the spontaneous depurination-depyrimidination of the modified bases and the aldehydic base and sugar lesions resulting from the oxidative damage to deoxyribose moieties in the DNA molecules were measured by an aldehyde reactive probe and were estimated as the number of ADL per 106 nucleotides. With the addition of NADPH (100 micro M) and Cu(II) (20 micro M), nanomolar levels (100 nM) of 4-OH-E2 and 2-OH-E2 induced approximately 10-fold increases in the number of ADL over control (P<0.001). In parallel, increases in 8-oxoguanine were detected in DNA exposed to 4-OH-E2 and 2-OH-E2 (100 nM) plus Cu(II) and NADPH. Further investigation indicated that the ADL induced by estrogen catechols plus Cu(II) and NADPH were causally involved in the formation of hydrogen peroxide and Cu(I). Both E2-2,3-Q and E2-3,4-Q alone induced a 2-fold increase in the number of ADL over control (P<0.05) in CT-DNA at high concentrations (1 mM). Neither neutral thermal hydrolysis nor lower ionic strength of the reaction medium induced further increases in the number of ADL in E2-3,4-Q-modified CT-DNA. Conversely, with the inclusion of Cu(II) and NADPH, both E2-3,4-Q and E2-2,3-Q (1 micro M) induced parallel formation of DNA single strand breaks and approximately 20-fold increases in the number of ADL over control (P < 0.001). The data also demonstrated that the ADL induced by estrogen quinones with and without the presence of Cu(II) and NADPH contain 69 and 78% putrescine-excisable ADL in CT-DNA, respectively. Additionally, results of the ADL cleavage assay indicate that the ADL induced by estrogen quinones plus Cu(II) and NADPH in CT-DNA were predominantly T7 exonuclease-excisable (50%) and exonuclease III- excisable (20%) ADL, whereas the intact ADL, and other ADL accounted for 5 and 25%, respectively. These results suggest that the ADL induced by estrogen quinones in CT-DNA are derived from oxidative events rather than depurination/depyrimidination of labile estrogen quinone-DNA adducts. Overall, our results are at variance with the idea that depurination of estrogen quinone-DNA adducts is the major source for the formation of ADL in genomic DNA. We hypothesize that in addition to DNA adducts and oxidized bases, the ADL induced by estrogen quinonoid-mediated oxidative stress may play a role in estrogen-induced carcinogenicity.


Asunto(s)
Aldehídos/metabolismo , Daño del ADN , Estradiol/análogos & derivados , Estrógenos de Catecol/toxicidad , Guanina/análogos & derivados , Animales , Bovinos , Cobre/farmacología , Aductos de ADN/análisis , Estradiol/toxicidad , Guanina/biosíntesis , NADP/farmacología , Estrés Oxidativo , Especies Reactivas de Oxígeno
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