RESUMEN
Fruit and nut shells can exhibit high hardness and toughness. In the peninsula of Yucatan, Mexico, the fruit of the Cocoyol palm tree (Acrocomia mexicana) is well known to be very difficult to break. Its hardness has been documented since the 1500 s, and is even mentioned in the popular Maya legend The Dwarf of Uxmal. However, until now, no scientific studies quantifying the mechanical performance of the Cocoyol endocarp has been found in the literature to prove or disprove that this fruit shell is indeed "very hard". Here we report the mechanical properties, microstructure and hardness of this material. The mechanical measurements showed compressive strength values of up to ~150 and ~250 MPa under quasi-static and high strain rate loading conditions, respectively, and microhardness of up to ~0.36 GPa. Our findings reveal a complex hierarchical structure showing that the Cocoyol shell is a functionally graded material with distinctive layers along the radial directions. These findings demonstrate that structure-property relationships make this material hard and tough. The mechanical results and the microstructure presented herein encourage designing new types of bioinspired superior synthetic materials.
Asunto(s)
Arecaceae , Frutas , Fenómenos Mecánicos , Fenómenos Biomecánicos , Fuerza Compresiva , DurezaRESUMEN
MicroRNAs (miRNAs) play an important role in drug resistance and modulate the efficiency of chemotherapy. A recent study indicated that miR-340 functions as a tumor suppressor in various types of cancer. However, the role of miR-340 in chemotherapy has not been reported yet. In this study, we found that miR-340 enhanced cisplatin (CDDP)-induced cell death. Induction of miR-340-5p expression decreased the IC50 of CDDP and increased the apoptosis of CDDP-resistant MG-63 and Saos-2 cells. Moreover, miR-340-5p decreased the accumulation of MRP1 and MDR1. We further explored the mechanism underlying the promoting effects of miR-340-5p on CDDP-induced cell death. We identified a potential target of miR-340 in the 3' untranslated region of lysophosphatidic acid acyltransferase (LPAATß) using the online program Targetscan (http://www.microrna.org). Luciferase reporter assays showed that miR-340 binds to the 3'UTR of LPAATß. Enforced expression of miR-340-5p decreased the accumulation of LPAATß in both MG-63 and Saos-2 cells. Silencing LPAATß decreased the IC50 of CDDP and increased the apoptosis of CDDP-resistant MG-63 and Saos-2 cells, which is consistent with the effect of miR-340-5p on CDDP-induced cell death. Moreover, induced expression of LPAATß compromised the effects of miR-340-5p on CDDP-induced cell death and accumulation of MRP1 and MDR1. Taken together, our data indicated that miR-340-5p enhanced the sensitivity to CDDP by targeting LPAATß.
Asunto(s)
Aciltransferasas/fisiología , Antineoplásicos/farmacología , Neoplasias Óseas/tratamiento farmacológico , Cisplatino/farmacología , Resistencia a Antineoplásicos/fisiología , MicroARNs/fisiología , Osteosarcoma/tratamiento farmacológico , Aciltransferasas/análisis , Aciltransferasas/efectos de los fármacos , Apoptosis/efectos de los fármacos , Western Blotting , Neoplasias Óseas/fisiopatología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Luciferasas , MicroARNs/análisis , MicroARNs/efectos de los fármacos , Osteosarcoma/fisiopatología , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
MicroRNAs (miRNAs) play an important role in drug resistance and modulate the efficiency of chemotherapy. A recent study indicated that miR-340 functions as a tumor suppressor in various types of cancer. However, the role of miR-340 in chemotherapy has not been reported yet. In this study, we found that miR-340 enhanced cisplatin (CDDP)-induced cell death. Induction of miR-340-5p expression decreased the IC50 of CDDP and increased the apoptosis of CDDP-resistant MG-63 and Saos-2 cells. Moreover, miR-340-5p decreased the accumulation of MRP1 and MDR1. We further explored the mechanism underlying the promoting effects of miR-340-5p on CDDP-induced cell death. We identified a potential target of miR-340 in the 3′ untranslated region of lysophosphatidic acid acyltransferase (LPAATβ) using the online program Targetscan (http://www.microrna.org). Luciferase reporter assays showed that miR-340 binds to the 3′UTR of LPAATβ. Enforced expression of miR-340-5p decreased the accumulation of LPAATβ in both MG-63 and Saos-2 cells. Silencing LPAATβ decreased the IC50 of CDDP and increased the apoptosis of CDDP-resistant MG-63 and Saos-2 cells, which is consistent with the effect of miR-340-5p on CDDP-induced cell death. Moreover, induced expression of LPAATβ compromised the effects of miR-340-5p on CDDP-induced cell death and accumulation of MRP1 and MDR1. Taken together, our data indicated that miR-340-5p enhanced the sensitivity to CDDP by targeting LPAATβ.
Asunto(s)
Humanos , Aciltransferasas/fisiología , Antineoplásicos/farmacología , Neoplasias Óseas/tratamiento farmacológico , Cisplatino/farmacología , Resistencia a Antineoplásicos/fisiología , MicroARNs/fisiología , Osteosarcoma/tratamiento farmacológico , Aciltransferasas/análisis , Aciltransferasas/efectos de los fármacos , Apoptosis/efectos de los fármacos , Western Blotting , Neoplasias Óseas/fisiopatología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo , Resistencia a Antineoplásicos/efectos de los fármacos , Luciferasas , MicroARNs/análisis , MicroARNs/efectos de los fármacos , Osteosarcoma/fisiopatología , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
In this study, the association between the 729G/C polymorphism in Toll-like receptor 4 (TLR4) and the risk of bladder cancer was investigated. A total of 376 patients with bladder cancer and 380 healthy volunteers from the Third Xiangya Hospital of Central South University (China) were enrolled in this study between January 2008 and February 2014. The TLR4-729G/C polymorphism was detected by the polymerase chain reaction-restriction fragment length polymorphism assay. There was a significant difference in the distribution of the TLR4-729G/C genotype between bladder cancer patients and healthy controls (P < 0.001). Our analysis showed that the GC genotype (OR = 2.99; 95%CI = 1.01-4.81, P = 0.046) and CC genotype (OR = 3.67; 95%CI = 2.11-7.27, P = 0.017) were significantly associated with increased bladder cancer risk when the GG genotype served as a reference. Furthermore, carriers of the C allele had a significantly increased risk of developing bladder cancer (OR = 3.89; 95%CI = 2.88-8.53; P = 0.009). Our results suggest a correlation between the TLR4-729G/C polymorphism and the risk of developing bladder cancer in this Chinese population.
Asunto(s)
Alelos , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Receptor Toll-Like 4/genética , Neoplasias de la Vejiga Urinaria/genética , Adulto , Anciano , Pueblo Asiatico/genética , Estudios de Casos y Controles , China , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Factores de RiesgoRESUMEN
PURPOSE: Increasing lines of evidence have suggested that adiponectin, an adipocyte-derived hormone, plays an important role in the development of hepatocellular carcinoma (HCC). However, the relationship between genetic variants of the adiponectin gene (ADIPOQ) and HCC has not been previously explored. Therefore, we performed a case-control study to examine the association of haplotype-tagging single-nucleotide polymorphisms (SNPs) in ADIPOQ with HCC risk. METHODS: Five haplotype-tagging SNPs of ADIPOQ (rs266729, rs822395, rs822396, rs2241766 and rs1501299) were genotyped in 200 HCC patients and 200 non-HCC controls by PCR amplification and direct sequencing. Logistic regression was used to estimate the risk of HCC associated with each individual SNP and we adjusted for multiple testing by the Bonferroni correction. RESULTS: Of the five tested SNPs, rs1501299 showed a strong and significant association with HCC risk even after the Bonferroni correction. After adjusting for the serological status of the hepatitis virus B core antibody and for other SNPs, the odds ratios were 4.33 [95 % confidence interval (CI) 2.07-9.05; corrected P < 0.005] and 3.71 (95 % CI 1.84-7.48; corrected P < 0.005) for the GG genotype and GG/GT combined genotype, respectively, versus the TT genotype. CONCLUSIONS: This is the first report, demonstrating an association of ADIPOQ polymorphisms with HCC risk. Our results implicate the ADIPOQ SNP rs1501299 as a susceptibility locus for HCC.
Asunto(s)
Adiponectina/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Polimorfismo de Nucleótido Simple , Adulto , Carcinoma Hepatocelular/epidemiología , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Neoplasias Hepáticas/epidemiología , Masculino , Persona de Mediana Edad , Factores de RiesgoRESUMEN
Saccharum spontaneum is a wild sugarcane species that is native to and widely distributed in China. It has been extensively used in sugarcane breeding programs, and is being tested for the development of bioenergy cultivars. In order to provide basic information for the exploitation of this species, we analyzed genetic variation among and within native S. spontaneum populations collected from Sichuan, China. Eighty plants from nine native populations were sampled. Twenty-one sequence-related amplified polymorphism primer pairs generated 235 clearly scorable bands, of which 185 were polymorphic (78.7%). Nei's genetic diversity was 0.2801 and Shannon's information index was 0.4155 across the populations. Genetic diversity parameters, G(ST) value (0.2088) and N(m) value (1.8944), showed that the genetic variation within populations was greater than that among populations. In the cluster analysis, one major grouping was formed by populations from Ya'an and another one by populations from Sichuan basin; a population from Baoxing formed a single cluster. In order to fully comprehend the genetic diversity of cold-tolerant local germplasm in this species, germplasm should be collected from the heterogeneous environments along the northern regions of this species' distribution. The germplasm that we collected should be a valuable resource for Saccharum breeding.
Asunto(s)
Variación Genética , Saccharum/genética , Secuencia de Bases , China , Cartilla de ADN , Reacción en Cadena de la PolimerasaRESUMEN
Epidemiologic studies have implicated Epstein-Barr virus (EBV) in the great majority (80%-100%) of Hodgkin disease (HD) cases in South American countries, versus only 30%-40% in the United States and other industrialized countries. Other EBV-related malignancies are known to be geographically localized, including nasopharyngeal carcinoma in south China and Burkitt lymphoma in equatorial Africa. Some studies, however, have suggested that age and histiotype, rather than geographic region, are the major determinants of the association between EBV and HD. To further characterize this relationship in children, we matched 26 cases of pediatric Hodgkin disease from south Brazil and 26 cases from the U.S.-forhistiotype and age. The Brazilian children (22 males, 4 females) had a median age of 9 years, while the median age of the U.S. group (11 males, 15 females) was 7.5 years. Formalin-fixed, paraffin-embedded biopsy material was examined for EBV early RNA1 (EBER1) expression by in situ hybridization. This antigen was detected solely in Reed-Sternberg cells or their variants in positive samples. The same proportion of cases was positive (15/26 or 58%) in both groups of children. After adjustment for histiotype and age, the association between EBV and HD remained independent of geographic location, but was more frequent in children aged < or = 10 years at diagnosis. These findings support the multiple-etiology hypothesis for Hodgkin disease.