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The Initial Upper Paleolithic (IUP) temporally overlaps with the range expansion of Homo sapiens populations in various parts of Eurasia and is often considered a key archaeological phase for investigating behavioral changes from the Middle Paleolithic. This paper reports upon new data from IUP occupations at Wadi Aghar, a rock shelter site in the southern Levant. In combining the results of radiometric dates and lithic analyses, we clarify the chronological and cultural position of Wadi Aghar assemblages in the Levantine IUP. As for the records about mobility, on-site activities, and resource procurement behaviors, we present analyses of lithic use-wear, tool-type composition, soil micromorphology, and marine shells. The lithic analyses and the optically stimulated luminescence (and subsidiary radiocarbon) dating of the Wadi Aghar materials suggest their chronocultural position in the IUP (45-40 ka for Layers C-D1; 39-36 ka for Layer B; possibly 50 ka for Layer D2), providing the southernmost location for the IUP in Eurasia. In the Levant, Wadi Aghar represents one of the few IUP sites in the inland areas. The results also indicate that the timing and technological sequences from the IUP to the following bladelet industries differed between the inland and coastal zones, likely reflecting geographically variable adaptive behaviors and/or cultural transmissions. One of the behavioral characteristics of IUP foragers at Wadi Aghar is the procurement of remote resources, represented by the transportation of marine shells from the Red Sea: Canarium fusiforme and Canarium cf. mutabile. Whether it was a direct procurement with increased mobility or a result of intergroup exchanges, it was not part of behavioral repertoires during the late MP in the same area. This can be understood as the expansion of resource procurement range, functioning as additional buffers from risk in the semiarid environments in the inland Levant.
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Fósiles , Tecnología , Exoesqueleto , Animales , Arqueología , Humanos , JordaniaRESUMEN
BACKGROUND: Sustained virological response (SVR) rates for the treatment of chronic hepatitis C virus (HCV)-infected patients have drastically improved with the use of direct-acting antiviral (DAA) therapies; however, a small minority of patients still fails to eradicate the virus. We analyzed factors associated with SVR in DAA therapy and the effect of age and liver fibrosis on treatment response. METHODS: Nine hundred and eighteen patients with chronic HCV infection were treated with 24 weeks of daclatasvir plus asunaprevir (DCV + ASV) or 12 weeks of sofosbuvir plus ledipasvir (SOF + LDV), ombitasvir, paritaprevir plus ritonavir (OMB + PTV + r) or sofosbuvir plus ribavirin (SOF + RBV). Multivariate logistic regression analysis was used to identify factors associated with SVR. The effect of age and liver fibrosis on SVR was analyzed. RESULTS: The overall SVR rate was 95.4% (876 of 918 patients), and rates by DAA regimen were 93.4%, 95.7%, 100%, and 95.0% in DCV + ASV-treated, SOF + LDV-treated, OMB + PTV + r-treated, and SOF + RBV-treated patients, respectively. Patients older than 75 years achieved a similar SVR rate with those aged 75 years or younger (96.4% and 94.8%, respectively). Multivariate logistic regression analysis identified absence of DAA therapy history (odds ratio [OR], 3.868 for presence; P = 0.002) and FIB-4 index of less than 3.25 (OR, 5.042 for ≥3.25; P = 0.001) as independent predictors for SVR. SVR rates were significantly lower in patients with FIB4 index of 3.25 or more compared with those with less than 3.25, especially in sofosbuvir-based therapies such as SOF + LDV-treated or SOF + RBV-treated patients. CONCLUSION: Both older and younger patients respond similarly to DAA therapy. Advanced liver fibrosis affects the virological response to sofosbuvir-based therapy.
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Antivirales/administración & dosificación , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Cirrosis Hepática/patología , Sofosbuvir/administración & dosificación , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Niño , Quimioterapia Combinada/métodos , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Respuesta Virológica Sostenida , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: In patients with advanced hepatocellular carcinoma (HCC), evidence is unclear as to whether hepatic arterial infusion chemotherapy (HAIC) or sorafenib is superior. We performed a prospective, open-label, non-comparative phase II study to assess survival with HAIC or HAIC converted to sorafenib. METHODS: Fifty-five patients were prospectively enrolled. Patients received HAIC as a second course if they had complete response, partial response, or stable disease (SD) with an alpha fetoprotein (AFP) ratio < 1 or a des-γ-carboxy prothrombin (DCP) ratio < 1. Patients were switched to sorafenib if they had SD with an AFP ratio > 1 and a DCP ratio > 1 or disease progression. The primary endpoint was the 1-year survival rate. Secondary endpoints were the 2-year survival rate, HAIC response, survival rate among HAIC responders, progression-free survival, and adverse events. RESULTS: Of the 55 patients in the intent-to-treat population, the 1-year and 2-year survival rates were 64.0 and 48.3%, respectively. After the first course of HAIC, one (1.8%) patient showed complete response, 13 (23.6%) showed partial response, 30 (54.5%) had SD, and 10 (18.1%) patients had progressive disease. Twenty-three patients (41.8%) had SD with AFP ratios < 1 or DCP ratios < 1, and 7 (12.7%) had SD with AFP ratios > 1 and DCP ratios > 1. Thirty-seven patients (68.5%) were responders and 17 (30.9%) were non-responders to HAIC. In responders, the 1-year and 2-year survival rates were 78 and 62%, respectively. CONCLUSION: Given the results of this study, this protocol deserves consideration for patients with advanced HCC. This trial was registered prospectively from December 12. 2012 to September 1. 2016.
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Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma Hepatocelular/tratamiento farmacológico , Infusiones Intraarteriales/métodos , Neoplasias Hepáticas/tratamiento farmacológico , Sorafenib/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Cisplatino/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Resultado del TratamientoRESUMEN
A small mass with an ulcer was found in the skin of the dorsal cervix of a 7-month-old male Sprague-Dawley rat. Histologically, the central region of the tumor showed a high cellular density with oval-shaped tumor cells arranged in an alveolar pattern and thin collagen fiber bundles. The peripheral region of the tumor had a low cellular density with short spindle- or polygonal-shaped tumor cells surrounded by abundant collagen fiber bundles. Immunohistochemically, the tumor cells were strongly positive for vimentin and proliferating cell nuclear antigen, and a portion of the short spindle- or polygonal-shaped cells located in the peripheral region of the tumor were positive for S100A4. However, the tumor cells were negative for alpha-smooth muscle actin, desmin, S100, chromogranin A, neurofilament, CD68, Iba-1, cytokeratin 20, von Willebrand factor, melanosome, and anti-melanoma. Electron microscopically, the tumor cells had an abundance of rough endoplasmic reticulum, the Golgi apparatus, and a few intracellular collagen fibrils, showing fibroblastic features. Considering the lack of diagnostic differentiation, the tumor was diagnosed as an undifferentiated malignant mesenchymal tumor and classified as a soft tissue sarcoma with differentiation into fibroblasts in a portion of the tumor cells.
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Although the lithic cutting-edge productivity has long been recognized as a quantifiable aspect of prehistoric human technological evolution, there remains uncertainty how the productivity changed during the Middle-to-Upper Paleolithic transition. Here we present the cutting-edge productivity of eight lithic assemblages in the eastern Mediterranean region that represent a chrono-cultural sequence including the Late Middle Paleolithic, Initial Upper Paleolithic, the Early Upper Paleolithic, and the Epipaleolithic. The results show that a major increase in the cutting-edge productivity does not coincide with the conventional Middle-Upper Paleolithic boundary characterized by the increase in blades in the Initial Upper Paleolithic, but it occurs later in association with the development of bladelet technology in the Early Upper Paleolithic. Given increasing discussions on the complexity of Middle-Upper Paleolithic cultural changes, it may be fruitful to have a long-term perspective and employ consistent criteria for diachronic comparisons to make objective assessment of how cultural changes proceeded across conventional chrono-cultural boundaries.
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The remote forcing from land surface changes in the Sahara is hypothesized to play a pivotal role in modulating the intensity of the East Asian summer monsoon (EASM) through ocean-atmospheric teleconnections. This modulation has far-reaching consequences, particularly in facilitating societal shifts documented in northern China. Here, we present a well-dated lake-level record from the Daihai Lake Basin in northern China, providing quantitative assessments of Holocene monsoonal precipitation and the consequent migrations of the northern boundary of the EASM. Our reconstruction, informed by a water-and-energy balance model, indicates that annual precipitation reached â¼700 mm during 8-5 ka, followed by a rapid decline to â¼550 mm between 5 and 4 ka. This shift coherently aligns with a significant â¼300 km northwestward movement of the EASM northern boundary during the Middle Holocene (MH), in contrast to its current position. Our findings underscore that these changes cannot be entirely attributed to orbital forcing, as corroborated by simulation tests. Climate model simulations deployed in our study suggest that the presence of the Green Sahara during the MH significantly strengthened the EASM and led to a northward shift of the monsoon rainfall belt. Conversely, the Sahara's reversion to a desert landscape in the late Holocene was accompanied by a corresponding southward retraction of monsoon influence. These dramatic hydroclimate changes during â¼5-4 ka likely triggered or at least contributed to a shift in Neolithic cultures and societal transformation in northern China. With decreasing agricultural productivity, communities transitioned from millet farming to a mixed rainfed agriculture and animal husbandry system. Thus, our findings elucidate not only the variability of the EASM but also the profound implications of a remote forcing, such as surface transformations of the Sahara, on climatic changes and cultural evolution in northern China.
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Scour ponds from unusually large tsunamis cut across the crest of a beach ridge in Kiritappu marsh, eastern Hokkaido. No fewer than ten of these ponds were imaged by photogrammetry as elongate topographic depressions as large as 5 m by 30 m. Sediments in these ponds are underlain by unconformities that were detected with ground-penetrating radar and observed directly in cores and a slice sample. Sediment deposits in the ponds contain peat and volcanic ash layers, the ages of which suggest that the scouring occurred during tsunamis generated by spatially extensive thrust ruptures along the southern Kuril trench, most recently during the early seventeenth century and its predecessor during the thirteenth-fourteenth century. Some of the ponds appear to have been formed during one tsunami and refreshed during later successors. This evidence of recurrent erosion suggests that the shoreline may retreat as part of earthquake-related cycles of coastal uplift and subsidence.
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The Ba Lai distributary channel of the Mekong River Delta was abandoned and infilled with sediment during the Late Holocene, providing a unique opportunity to investigate the sediment fill, timing and mechanisms of channel abandonment in tide-dominated deltaic systems. Based on analysis and age dating of four sediment cores, we show that the channel was active since 2.6 ka and was abandoned at 0.7 ka as marked by the abrupt disappearance of the sand fraction and increase in organic matter and sediment accumulation rate. We estimate that the channel might have been filled in a time range of 45-263 years after detachment from the deltaic network, with sediment accumulation rates of centimetres to decimetres per year, rapidly storing approximately 600 Mt of organic-rich mud. We suggest that the channel was abandoned due to a sediment buildup favoured by an increase in regional sediment supply to the delta. This study highlights that mechanisms for abandonment and infilling of tide-dominated deltaic channels do not entirely fit widely used models developed for fluvial-dominated environments. Their abandonment might be driven by autogenic factors related to the river-tidal and deltaic dynamics and favoured by allogenic factors (e.g., human impact and/or climate change).
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INTRODUCTION: The effect of beta3-adrenergic receptor agonists on beta cells in the islets of Langerhans is not yet clear. This study examined the beta3-adrenergic receptor agonist on beta cells in the islets of Langerhans. METHODS: Obese diabetic C57BL/KsJ-db/db mice were treated with KTO-7924, a newly-developed beta3-adrenergic receptor agonist for 28-day. We analyzed plasma parameters, insulin resistance, and insulin-positive areas among beta-cells in the islets of Langerhans. RESULTS AND CONCLUSION: After a 28-day oral administration period, plasma levels of hemoglobin (Hb) A1c, glucose, triglyceride (TG), and free fatty acid (FFA) were all significantly reduced in KTO-7924 treatment groups compared with controls. Plasma adiponectin levels decreased with age in the control group, but were significantly higher in a treatment group throughout the study period. Furthermore, sequential administration of KTO-7924 led to an improvement in insulin resistance in the OGTT (Oral glucose tolerance test (OGTT)), and an increase in the percentage of insulin-positive areas among beta-cells in the islets of Langerhans compared with controls. This is the first study to show islet histology after treatment of a beta3-adrenergic receptor agonist, and reveals that KTO-7924 reduces hyperglycemia, and protects beta-cells in the islets of Langerhans of db/db mice.
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Agonistas Adrenérgicos/farmacología , Hiperglucemia/sangre , Hiperglucemia/tratamiento farmacológico , Células Secretoras de Insulina/efectos de los fármacos , Adiponectina/sangre , Adiponectina/genética , Animales , Glucemia/metabolismo , Ácidos Grasos no Esterificados/sangre , Prueba de Tolerancia a la Glucosa , Hemoglobina Glucada/metabolismo , Hiperglucemia/patología , Insulina/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , ARN/química , ARN/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Triglicéridos/sangreRESUMEN
Since the 1990s the Mekong River delta has suffered a large decline in sediment supply causing coastal erosion, following catchment disturbance through hydropower dam construction and sand extraction. However, our new geological reconstruction of 2500-years of delta shoreline changes show that serious coastal erosion actually started much earlier. Data shows the sandy coast bounding river mouths accreted consistently at a rate of +2 to +4 km2/year. In contrast, we identified a variable accretion rate of the muddy deltaic protrusion at Camau; it was < +1 km2/year before 1400 years ago but increased drastically around 600 years ago, forming the entire Camau Peninsula. This high level of mud supply had sharply declined by the early 20th century after a vast canal network was built on the delta. Since then the Peninsula has been eroding, promoted by the conjunction of mud sequestration in the delta plain driven by expansion of rice cultivation, and hysteresis of long-term muddy sedimentation that left the protrusion exposed to wave erosion. Natural mitigation would require substantial increases in sediment supply well above the pre-1990s levels.
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AIM: The aim of this study was to investigate the preventive actions of bezafibrate against non-alcoholic steatohepatitis (NASH), the activation of hepatic stellate cells (HSC), and fibrogenesis by using a model of NASH and an in vitro model. METHODS: Male KK-A(y)/TaJcl (KK-A(y)) mice were fed a methionine and choline-deficient (MCD) diet or a MCD diet containing bezafibrate or pioglitazone for 7 weeks, after which biochemical parameters, pathological changes, and hepatic mRNA levels were assessed. An in vitro HSC model was designed by using a previously described RI-T cell line stimulated by transforming growth factor-beta1 (TGF-beta1). RESULTS: MCD diet-fed KK-A(y) mice developed hepatic steatosis, oxidative stress, inflammation, and hepatic fibrosis. Bezafibrate markedly decreased the hepatic content of triglyceride accumulation of fatty droplets within hepatocytes, and increased the expression of hepatic fatty acid beta-oxidative genes in MCD diet-fed KK-A(y) mice. Bezafibrate markedly inhibited the increases in the plasma alanine aminotransferase level and hepatic content of thiobarbituric acid-reactive substances in this model. Moreover, it dramatically reduced hepatic inflammatory changes and fibrosis concomitantly with marked reductions in the mRNA levels for inflammatory cytokine, chemokine, and profibrogenic genes. Importantly, both bezafibrate and pioglitazone markedly reduced the mRNA levels of profibrogenic and fibrogenic genes in TGF-beta1-stimulated cells. CONCLUSION: Bezafibrate improved hepatic steatosis and potently prevented inflammation, oxidative stress, HSC activation, and fibrogenesis in the liver. Moreover, this study was the first to demonstrate that bezafibrate directly inhibits hepatic fibrogenic response induced by TGF-beta1 in vitro. Hence bezafibrate may be a new therapeutic strategy against NASH and hepatic fibrosis.
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BACKGROUND: In Japan, daclatasvir (DCV) and asunaprevir (ASV) therapy was the first IFN-free treatment to be approved, and thousands of patients have since been successfully treated, with an SVR rate of around 90%. The converse, however, is that around 10% of patients fail to achieve viral eradication and must be retreated using a different approach. This study is to evaluate treatment efficacy of ledipasvir/sofosbuvir and ribavirin in patients who failed to respond to DCV and ASV therapy. METHODS: Thirty patients were treated with 12 weeks of ledipasvir/sofosbuvir and ribavirin. We evaluated the rate of sustained virological response 12 weeks after the end of treatment (SVR12) and examined the incidence of adverse events during ledipasvir/sofosbuvir and ribavirin treatment. NS5A and NS5B resistance-associated variants (RAVs) in treatment failure cases were examined. RESULTS: The overall SVR12 rate was 86.7% (26/30). Large decreases in mean log10 HCV RNA levels were observed in patients without cirrhosis, and the SVR12 rate for these patients was 100% (12/12). In cases of cirrhosis, SVR12 rate was 72.2% (13/18). The common factors in treatment failure cases were the presence of liver cirrhosis and both NS5A L31M/I and Y93H RAVs. The frequency of RAVs did not change before and after treatment among patients who relapsed. CONCLUSION: Ledipasvir/sofosbuvir with ribavirin is an effective retreatment option for patients with chronic hepatitis C who failed to respond to prior daclatasvir and asunaprevir therapy.
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Antivirales/uso terapéutico , Bencimidazoles/uso terapéutico , Fluorenos/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Ribavirina/uso terapéutico , Uridina Monofosfato/análogos & derivados , Anciano , Anciano de 80 o más Años , Antivirales/efectos adversos , Bencimidazoles/efectos adversos , Carbamatos , Quimioterapia Combinada , Femenino , Fluorenos/efectos adversos , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/virología , Humanos , Imidazoles/uso terapéutico , Isoquinolinas/uso terapéutico , Masculino , Persona de Mediana Edad , Proyectos Piloto , Pirrolidinas , ARN Viral/sangre , Retratamiento/efectos adversos , Retratamiento/métodos , Ribavirina/efectos adversos , Sofosbuvir , Sulfonamidas/uso terapéutico , Respuesta Virológica Sostenida , Insuficiencia del Tratamiento , Resultado del Tratamiento , Uridina Monofosfato/efectos adversos , Uridina Monofosfato/uso terapéutico , Valina/análogos & derivadosRESUMEN
BACKGROUND: Polymorphisms in the inosine triphosphatase (ITPA) gene is associated with anemia induced by peg-interferon (PEG-IFN) plus ribavirin (RBV) treatment for patients with chronic hepatitis C virus (HCV) infection. However, the effect of ITPA polymorphism on sofosbuvir plus RBV treatment is unknown. METHODS: Two hundred and forty-four patients with chronic HCV genotype 2 infection without decompensated liver cirrhosis were treated with sofosbuvir plus RBV for 12 weeks. The effects of ITPA polymorphism on hemoglobin levels and RBV dose reduction and treatment response were analyzed. ITPA (rs1127354) was genotyped using the Invader assay. Multivariate regression analysis was performed to identify factors associated with sustained virological response (SVR). RESULTS: Overall, SVR12 was achieved in 231 (94.7%) patients, based on intention to treat analysis. During the therapy, reduction of hemoglobin levels was significantly greater in ITPA genotype CC patients than CA/AA patients. Therefore, the cumulative proportion of patients with RBV dose reduction was significantly higher and total dose of RBV was significantly lower in patients with CC genotype compared to CA/AA genotypes. SVR12 rates were similar between ITPA genotypes CC and CA/AA (94.7 and 94.4%, respectively, P = 0.933). Multivariate logistic regression analysis identified FIB4 index <3.25 (odds ratio [OR], 9.388 for ≥3.25; P = 0.005) and low body weight (OR, 1.059, for high body weight; P = 0.017) as independent predictors for SVR12. CONCLUSIONS: ITPA polymorphism influences hemoglobin levels and incidence of RBV dose reduction during sofosbuvir plus RBV therapy. However, ITPA genotype CC patients can expect a curative effect equivalent to CA/AA patients for chronic HCV genotype 2 infection.
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Antivirales/administración & dosificación , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Pirofosfatasas/genética , Adulto , Anciano , Anciano de 80 o más Años , Antivirales/uso terapéutico , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Femenino , Genotipo , Hemoglobinas/metabolismo , Hepatitis C Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Ribavirina/administración & dosificación , Ribavirina/uso terapéutico , Sofosbuvir/administración & dosificación , Sofosbuvir/uso terapéutico , Resultado del Tratamiento , Inosina TrifosfatasaRESUMEN
We evaluated the effects of bezafibrate, a peroxisome proliferator-activated receptor (PPAR) pan-agonist, and GW501516, a PPARdelta agonist, on mice fed a methionine- and choline-deficient (MCD) diet, a model of non-alcholic steatohepatitis (NASH), to investigate (a) the efficacy of bezafibrate against non-alcholic steatohepatitis and (b) the relation between non-alcholic steatohepatitis and the functional role of PPARdelta. Bezafibrate (50 or 100 mg/kg/day) and GW501516 (10 mg/kg/day) were administered by gavage once a day for 5 weeks. Hepatic lipid contents, plasma triglyceride, high density lipoprotein (HDL)-cholesterol and alanine aminotransferase (ALT) concentrations were evaluated, as were histopathological changes in the liver and hepatic mRNA expression levels. Bezafibrate and GW501516 inhibited the MCD-diet-induced elevations of hepatic triglyceride and thiobarbituric acid-reactants contents and the histopathological increases in fatty droplets within hepatocytes, liver inflammation and number of activated hepatic stellate cells. In this model, bezafibrate and GW501516 increased the levels of hepatic mRNAs associated with fatty acid beta-oxidation [acyl-CoA oxidase (ACO), carnitine palmitoyltransferase-1 (CPT-1), liver-fatty acid binding protein (L-FABP) and peroxisomal ketothiolase], and reduced the levels of those associated with inflammatory cytokines or chemokine [transforming growth factor (TGF)-beta1, interleukin (IL)-6, IL-1beta, monocyte chemoattractant protein (MCP)-1, tumor necrosis factor (TNF) alpha and nuclear factor (NF)-kappaB1]. In addition, bezafibrate characteristically reduced the elevation in the level of plasma ALT, but enhanced that in plasma adiponectin and increased the mRNA expression levels of its receptors (adiponectin receptors 1 and 2). These results suggest that (a) bezafibrate (especially) and GW501516 might improve hepatic steatosis via an improvement in fatty acid beta-oxidation and a direct prevention of inflammation, (b) treatment with a PPARdelta agonist might improve non-alcholic steatohepatitis, (c) bezafibrate may improve non-alcholic steatohepatitis via activation not only of PPARalpha but also of PPARdelta, because bezafibrate is a PPAR pan-agonist.
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Bezafibrato/farmacología , Dieta/efectos adversos , Hígado Graso/prevención & control , Tiazoles/farmacología , Acil-CoA Oxidasa/genética , Alanina Transaminasa/sangre , Animales , Bezafibrato/administración & dosificación , Carnitina O-Palmitoiltransferasa/genética , HDL-Colesterol/sangre , Colina/administración & dosificación , Relación Dosis-Respuesta a Droga , Proteínas de Unión a Ácidos Grasos/genética , Hígado Graso/sangre , Hígado Graso/etiología , Expresión Génica/efectos de los fármacos , Interleucina-6/genética , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Metionina/administración & dosificación , Ratones , Ratones Endogámicos C57BL , PPAR delta/agonistas , Receptores Activados del Proliferador del Peroxisoma/agonistas , ARN Mensajero/genética , ARN Mensajero/metabolismo , Tiazoles/administración & dosificación , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta1 , Triglicéridos/sangre , Triglicéridos/metabolismoRESUMEN
To clarify the in vivo genotoxic potential of kojic acid (KA), formation of DNA adducts and 8-hydroxy-deoxyguanosine (8-OHdG) in the thyroids of male rats subjected to dietary administration of 2% KA for 2 weeks were assessed by 32P-postlabeling analysis and with a high-performance liquid chromatography system coupled to an electrochemical detector (ECD), respectively. In addition, to investigate possible tumor initiation activity, male F344 rats were given diet containing 0, 0.02, 0.2 or 2% kojic acid for 8 weeks followed by administration of 0.1% sulfadimethoxine (SDM), a thyroid tumor promoter, in the drinking water for 23 weeks with a subsequent 13-week recovery period (two-stage thyroid tumorigenesis model). Rats given four times by s.c. injection of N-bis(2-hydroxypropyl)nitrosamine (DHPN; 700 mg/kg bw) during the initiation period followed by administration of 0.1% SDM and rats given diet containing 2% KA for the initial 8 weeks or for the entire 31 weeks of the experiment, or basal diet alone were provided as controls. DNA adducts were not formed, and the 8-OHdG level was not increased in the thyroids of rats given 2% KA for 2 weeks. In the two-stage thyroid tumorigenesis model, neither adenomas nor carcinomas were induced in the groups given 0, 0.02, 0.2 or 2% KA followed by 0.1% SDM administration, and incidences and multiplicities of focal follicular cell hyperplasias did not demonstrate any significant intergroup differences at the end of administration and recovery periods. In contrast, incidences and multiplicities of focal follicular cell hyperplasias, adenomas and carcinomas were all significantly increased in the DHPN + 0.1% SDM group. Although the incidences and multiplicities of focal follicular cell hyperplasias in the group given 2% KA for 31 weeks were greater than those in the 2% KA + 0.1% SDM group and an adenoma was observed in a rat at the end of the recovery period, no development of carcinomas was evident at either time point. No thyroid proliferative lesions were induced in the group given 2% KA for the initial 8 weeks only. The results of the present studies indicate that KA has neither in vivo genotoxic potential nor tumor initiation activity in the thyroid, and strongly suggest that the earlier observed thyroid tumorigenic activity of KA is attributable to a non-genotoxic mechanism.
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Carcinógenos/toxicidad , Pironas/toxicidad , Glándula Tiroides/efectos de los fármacos , Neoplasias de la Tiroides/inducido químicamente , 8-Hidroxi-2'-Desoxicoguanosina , Adenoma/inducido químicamente , Adenoma/patología , Animales , Carcinoma/inducido químicamente , Carcinoma/patología , Aductos de ADN/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Hiperplasia/inducido químicamente , Hiperplasia/patología , Masculino , Ratas , Ratas Endogámicas F344 , Glándula Tiroides/metabolismo , Glándula Tiroides/patología , Neoplasias de la Tiroides/patologíaRESUMEN
The toxicity profile of silodosin, a selective alpha(1A)-adrenoceptor antagonist, was evaluated. The lethal doses were 800 mg/kg in rats and 1500 mg/kg in dogs. Repeated-dose studies revealed fatty degeneration of hepatocytes and an induction of drug-metabolizing enzymes at 15 mg/kg/day or more in male rats, mammary gland hyperplasia at 60 mg/kg/day or more in female rats, and degeneration of the seminiferous tubular epithelium at 25 mg/kg/day or more only in young dogs. Silodosin was negative in all mutagenicity studies, except for a weak positive in a chromosomal aberration assay conducted without metabolic activation. In carcinogenicity studies, mammary gland tumors and pituitary adenomas were increased in female mice given 150 mg/kg/day or more and 400 mg/kg/day respectively, while thyroid follicular cell carcinoma was increased in male rats given 150 mg/kg/day. Reproductive studies in rats revealed a decreased male fertility at 20 mg/kg/day or more and a prolonged estrous cycle at 60 mg/kg/day or more. Silodosin did not exhibit any teratogenic potential in either rats or rabbits, and had no effects on the postnatal development of rat offspring. In safety pharmacology studies, silodosin produced no severe effects on the central nervous, cardiovascular, or respiratory systems. In conclusion, silodosin exhibited adequate safety margins between the clinically recommended dose and those at which toxic effects or safety pharmacological changes were detected. As a new therapeutic drug for the micturition difficulties caused by benign prostatic hyperplasia, silodosin should have few serious side effects in clinical use.
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Antagonistas Adrenérgicos alfa/toxicidad , Indoles/toxicidad , Pruebas de Toxicidad , Antagonistas de Receptores Adrenérgicos alfa 1 , Antagonistas Adrenérgicos alfa/administración & dosificación , Antagonistas Adrenérgicos alfa/farmacología , Animales , Cricetinae , Perros , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Femenino , Cobayas , Indoles/administración & dosificación , Indoles/farmacología , Dosificación Letal Mediana , Masculino , Ratones , Embarazo , Conejos , RatasRESUMEN
We recently reported that short-term treatment with KAT-681 (KAT), a liver-selective thyromimetic, inhibits the development of preneoplastic lesions in rat livers and may be a candidate chemopreventive agent for hepatocarcinogenesis. In this study, time-course observations of hepatocellular proliferative lesions were carried out during short-term and long-term treatment with KAT to investigate its anti-hepatocarcinogenic effects. The hepatocellular proliferative lesions in male F344 rats were induced by the initiation treatment of diethylnitrosamine (DEN), followed by treatment with 2-acetylaminofluorene (2-AAF) and partial hepatectomy (PH). The rats were administered KAT orally at a dose of 0.25 mg/kg/day for 3 weeks (experiment 1) or 0.1 mg/kg/day for 20 weeks (experiment 2). In experiment 1, a serial reduction in the number of altered hepatocellular foci (AHF) with positive expression of glutathione S-transferase placental form (GST-P) was observed until day 14 of the treatment period. The proliferative index (PI) of hepatocytes in the AHF significantly increased in the KAT group throughout the treatment period, with a peak on day 2. KAT treatment showed no obvious effects on GST-P-positive hepatocellular adenomas (HCAs) at any time point. In contrast, long-term KAT treatment in experiment 2 revealed a reduction in the mean size of HCAs in addition to reductions in the number and mean size of AHF. The PIs within the lesions in KAT-treated rats were significantly lower than those in controls. The present study indicates that KAT has different inhibitory effects on hepatocarcinogenesis in the early and late phases of KAT treatment; there is a reduction in AHF with enhanced cell proliferation in the early phase and the inhibition of development of AHF and HCAs with suppression of cell proliferation in the late phase. These results may suggest further potential of KAT as a promising chemopreventive agent for hepatocarcinogenesis.
Asunto(s)
2-Acetilaminofluoreno/antagonistas & inhibidores , 2-Acetilaminofluoreno/toxicidad , Anticarcinógenos/farmacología , Carcinógenos/antagonistas & inhibidores , Carcinógenos/toxicidad , Dietilnitrosamina/toxicidad , Hepatectomía , Neoplasias Hepáticas/inducido químicamente , Hígado/efectos de los fármacos , Malonatos/farmacología , Éteres Fenílicos/farmacología , Hormonas Tiroideas/farmacología , Animales , Apoptosis/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Glutatión Transferasa/metabolismo , Inmunohistoquímica , Neoplasias Hepáticas/enzimología , Neoplasias Hepáticas/patología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Antígeno Nuclear de Célula en Proliferación/metabolismo , Ratas , Ratas Endogámicas F344RESUMEN
To assess the effectiveness of the multiple dose liver micronucleus (MN) assay, the induction of micronuclei by N-nitrosodi-n-propylamine (NDPA), a genotoxic rodent carcinogen, was compared in hepatocytes (HEPs) and bone marrow (BM) cells. Young adult male rats were treated orally with NDPA at 6 weeks of age for 14 days using daily doses of 10, 20 and 40mg/kg. Samples of the liver and BM tissues were harvested from each animal one day following the last treatment with NDPA and were evaluated for the frequencies of micronucleated cells. Repeated doses with 40mg/kg/day of NDPA caused systemic and hepatic toxicity, including suppressed body weight gains and histopathological hepatic lesions. The frequencies of micronucleated HEPs were significantly increased in all the NDPA-treated groups in a dose-dependent manner. In contrast, the induction of micronuclei in the BM was undetectable, even at the high dose level of 40mg/kg, for which the inhibition of hematopoiesis was observed. For the detection of micronucleated HEPs induced by NDPA treatment, a 14-day administration period is adequate. The liver MN assay using naive young adult rats may be integrated into general repeated-dose toxicity studies including histopathological examinations. Our results suggest that the liver MN assay using multiple doses is more efficient and sensitive than the BM MN assay in detecting the in vivo genotoxic potential of NDPA.
Asunto(s)
Carcinógenos/toxicidad , Hepatocitos/efectos de los fármacos , Hígado/efectos de los fármacos , Pruebas de Micronúcleos , Nitrosaminas/toxicidad , Administración Oral , Factores de Edad , Animales , Peso Corporal/efectos de los fármacos , Médula Ósea/efectos de los fármacos , Aberraciones Cromosómicas/efectos de los fármacos , Conducta Cooperativa , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Hepatocitos/patología , Humanos , Japón , Hígado/patología , Masculino , Especificidad de Órganos , Ratas , Ratas Sprague-Dawley , Sociedades FarmacéuticasRESUMEN
Previously we reported a lack of modification by cinnamaldehyde (CNMA) of development of lung proliferative lesions induced by urethane in CB6F1-TgHras2 (rasH2) mice. In the present study, we re-evaluated CNMA effects using the same rasH2 strain and non-transgenic littermates initiated with 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). Sixteen mice/strain/sex received intraperitoneal NNK injections at a dose of 3 mg/mouse once a week for 2 weeks followed by free feeding of commercial diet containing 5000 ppm CNMA for 26 weeks. Additional groups were maintained without NNK injection and/or CNMA feeding for 28 weeks. Lung tumors were induced by NNK in both rasH2 and non-Tg males and females at incidence ranging from 63 to 100%. CNMA treatment significantly reduced the combined incidence of adenomas and carcinomas from 86 to 31% in rasH2 males (P<0.05), but no significant influence was evident in females. The multiplicity of NNK-induced lung tumors was also significantly reduced in rasH2 males given CNMA (P<0.01). Similar effects were also observed in non-Tg females given CNMA after NNK initiation. The results of our study strongly indicate that CNMA is capable of inhibiting development of NNK-initiated pulmonary tumorigenesis in rasH2 and non-Tg mice.
Asunto(s)
Carcinógenos/farmacología , Neoplasias Pulmonares/prevención & control , Nitrosaminas/farmacología , Proteínas ras/genética , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos , Ratones TransgénicosRESUMEN
In order to improve the sensitivity of our previously established thyroid carcinogenesis model and to clarify whether endocrine disrupting chemicals with weak estrogenic activity have any modifying effects on the development of thyroid proliferative lesions, 6-week-old female castrated F344 rats were first given a single subcutaneous injection of 2000 mg/kg body weight of N-bis(2-hydroxypropyl)nitrosamine. From 1 week later, they received diets with: no supplement (basal diet (BD) group); cholesterol pellets containing 0.5 mg 17 beta-estradiol 3-benzoate (EB); or diet admixed with 1000 ppm methoxychlor (MXC) or 10,000 ppm bisphenol A (BPA) for 20 weeks. Furthermore, additional groups were administered 200 ppm sulfadimethoxine (SDM) in the drinking water simultaneously with the BD, EB, MXC or BPA treatments. Thyroid follicular cell hyperplasias, adenomas and/or carcinomas were induced only in the EB+SDM group, the incidences of non-malignant lesions being significantly increased, as compared with the BD+SDM group values. Furthermore, the serum level of thyroid stimulating hormone (TSH) was significantly increased in this group. No significant variation in quantitative values for thyroid proliferative lesions or TSH levels were observed in the other treated groups. The results of the present study convincingly indicate that EB, with strong estrogenic activity, but not MXC and BPA, with weak estrogenic activities, exerts promoting effects on thyroid carcinogenesis in rats. The present modified rat two-stage thyroid carcinogenesis model appears to have advantages over our previous model for screening purposes.