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1.
Nat Commun ; 15(1): 1044, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316815

RESUMO

Reinforcement learning (RL) stands as one of the three fundamental paradigms within machine learning and has made a substantial leap to build general-purpose learning systems. However, using traditional electrical computers to simulate agent-environment interactions in RL models consumes tremendous computing resources, posing a significant challenge to the efficiency of RL. Here, we propose a universal framework that utilizes a photonic integrated circuit (PIC) to simulate the interactions in RL for improving the algorithm efficiency. High parallelism and precision on-chip optical interaction calculations are implemented with the assistance of link calibration in the hybrid architecture PIC. By introducing similarity information into the reward function of the RL model, PIC-RL successfully accomplishes perovskite materials synthesis task within a 3472-dimensional state space, resulting in a notable 56% improvement in efficiency. Our results validate the effectiveness of simulating RL algorithm interactions on the PIC platform, highlighting its potential to boost computing power in large-scale and sophisticated RL tasks.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38109812

RESUMO

Separation and purification of naturally occurring isomers from herbs are still challenging. High-speed counter-current chromatography (HSCCC) has been applied to isolate natural products. In this study, an off-line multi-dimensional high-speed counter-current chromatography (multi-D HSCCC) strategy was developed utilizing the in situ concentration technique with online storage recycling elution to rapidly separate bioactive isomeric neolignans from chloroform-partitioned samples of the plant Piper betle L. In the procedure, the crude sample (105 mg) was implemented using the online storage recycling technique in a two-phase solvent system composed of petroleum ether-ethyl acetate-methanol-water (7: 5: 12: 3), which first simply afforded a neolignane kadsurenone (1, 5.3 mg) and its epimer (-)-denudatin B (2, 6.4 mg). Then, the remains fr a was subjected to the second-dimensional HSCCC elution using the in situ concentration technique with online storage recycling technique in another solvent system of petroleum ether-ethyl acetate-methanol-water (5: 5: 11, 15). As a result, kadsurenin I (3, 0.6 mg) and its regioisomer pibeneolignan C (4, 5.0 mg), together with the fractional remaining fr b and fr c, were obtained. Thirdly, the fr c was reloaded to allow the HSCCC for recycling elution with the former solvent system employing the in situ concentration strategy and yielded a pair of epimers, (7R,8S,1'S)-1'-allyl-5-methoxy-8-methyl-7-piperonyl-7,8,3,6-tetrahydro-2-oxobenzofuran (5, 10.2 mg), and 3-epi-(-)-burchullin (6, 2.6 mg). Finally, the three pairs of less amount and the structurally similar isomers 1-6 were isolated from the crude fraction of P. betle with a high HPLC purity of over 95.0 % for compound 2, 4-6 and 92.5 % for compound 1, 91.0 % for 3, while the purity of 1 and 3 in 1H NMR were 89.9 % and 91.1 %, respectively. The whole isolation process was quick and efficient. Compounds 1, 2, 4 and 5 showed significantly synergistic activities combining several antibiotics against five drug-resistant Staphylococcus aureus with FICIs from 0.156 to 0.375. This novel off-line multi-dimensional HSCCC strategy could be broadened to application for the rapid separation of complex natural products.


Assuntos
Acetatos , Alcanos , Lignanas , Staphylococcus aureus Resistente à Meticilina , Piper betle , Distribuição Contracorrente/métodos , Metanol , Extratos Vegetais/química , Lignanas/análise , Cromatografia Líquida de Alta Pressão/métodos , Solventes , Água
3.
Biochem Biophys Res Commun ; 527(1): 218-225, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32446370

RESUMO

Even though earlier reports have revealed that Aquaporin 8 (AQP8) exert essential roles in diverse malignancies, its relationship between specific microRNAs (miRNAs) in regulation of colorectal carcinoma (CRC) progression has never been elaborated. Herein, we proved that AQP8 was downregulated in CRC and high level of AQP8 was significantly associated with better survival in CRC patients. Overexpression of AQP8 restrained CRC cell proliferation, migration and invasion capacities in vitro. In vivo, upregulation of AQP8 also suppressed CRC cell growth. Mechanistic analyses illustrated that AQP8 was a directly target of miR-92a. The expression of AQP8 was negatively modulated by miR-92a. Rescues analysis indicated that miR-92a facilitated CRC cell growth and invasion via modulating the expression of AQP8. Our work validated that miR-92a regulated the aggressiveness of CRC cell via targeting AQP8.


Assuntos
Aquaporinas/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , MicroRNAs/metabolismo , Aquaporinas/genética , Linhagem Celular , Proliferação de Células , Biologia Computacional , Humanos , MicroRNAs/genética
4.
Ying Yong Sheng Tai Xue Bao ; 31(12): 4147-4152, 2020 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-33393252

RESUMO

We examined the effects of shading photosynthetic characteristics, yield, and tolerance to low light in two potato varieties (Jizhangshu 12 and Jizhangshu 8) at four growth stages (seedling, seedling/budding, budding/early flowering and flowering/harvest). There were three shading treatments (0(CK), 20% and 50%). The results showed that at both 20% and 50% shading rates, the SPAD value (a measure of leaf cellular chlorophyll content) of the two varieties decreased significantly at the seedling stage compared with CK treatment. No significant change in the SPAD value occurred at the seedling/budding stage or the budding/early-flowering stage. However, the SPAD value increased marginally after shading at the initial flowering stage. Under the 50% shading regime, the SPAD values of both varieties followed the same trend as the 20% regime. The range of changes at different growth stages remained similar. The only exception was that shading at the beginning of flowering increased SPAD value. Shading had little effect on leaf stomatal conductance (gs) at each developmental stage. There was no significant difference between all treatments and the control, except that the gsvalue of Jizhangshu 8 decreased significantly (43.9%) compared with the control under 50% shading at the beginning of flowering. After the shading treatment, the intercellular CO2 concentration (Ci) of leaves showed an upward trend. 50% shading at the seedling and seedling/budding stages could significantly increase Ci, but not at other stages. The net photosynthetic rate (Pn) of the four periods were all decreased after 15 d of shading. The Pn reduction of the two varieties, 50% shading, was greater than 20% shading. The decline range of Pn of Jizhangshu 12 was less than that of Jizhangshu 8 at all stages, except for that at the seedling stage. The yield of shading treatments decreased in all four stages, with the decrease rate of 50% shading treatment being greater than that of the 20% shading treatment. 'Jizhangshu 12'was not tolerant to low light at the seedling stage but performed better than 'Jizhangshu 8' at other stages. The comprehensive analysis of two test varieties implied that varieties with strong tolerance to low light experienced a smaller boost in intercellular CO2 concentration and a smaller drop in net photosynthetic rate, stomatal conductance, and yield post-shading.


Assuntos
Solanum tuberosum , Clorofila , Fotossíntese , Folhas de Planta , Plântula
5.
Environ Sci Pollut Res Int ; 26(4): 4070-4077, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30554317

RESUMO

Greenhouse gas emissions from agricultural soils contribute substantially to global atmospheric composition. Nitrous oxide (N2O) is one important greenhouse gas induces global warming. Nitrification inhibitors (NI) or biochar can be effective soil N2O emission mitigation strategies for agricultural soils. However, due to differences in crop physiological traits or agricultural management, the effectiveness of mitigation strategies varies among agricultural systems. Camellia oleifera is a woody oil plant widely grown and requires intensive N input, which will potentially increase N2O emissions. Thereby, mitigation of N2O emissions from C. oleifera field soil is vital for sustainable C. oleifera development. Besides NI, incorporation of C. oleifera fruit shell-derived biochar into its soil will benefit waste management and simultaneous mitigation of N2O emissions but this has not been investigated. Here, we conducted two studies to examine effects of biochar addition and NI (dicyandiamide, DCD) application on N2O emissions from C. oleifera field soil with different N (urea or NH4NO3) and incubation temperatures. Biochar effects on nitrification rates varied among N treatments. Biochar applied in combination with DCD further reduced nitrification rates (for urea treatment, decreased from 1.1 to 0.3 mg kg-1 day-1). Biochar addition consistently increased soil N2O emissions (for urea treatment, increased from 0.03 to 0.08 ng g-1 h-1) and their temperature sensitivity. DCD application reduced soil N2O emissions with greater reductions with urea application. In future cultivation of intensively managed C. oleifera gardens, NI should be applied to mitigate N2O emissions if biochar is added, especially when urea is used.


Assuntos
Camellia , Carvão Vegetal , Gases de Efeito Estufa/análise , Guanidinas , Óxido Nitroso/análise , Agricultura/métodos , Camellia/química , Fertilizantes , Nitrificação/efeitos dos fármacos , Solo/química , Temperatura
6.
Zhonghua Nan Ke Xue ; 25(10): 867-873, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-32233216

RESUMO

OBJECTIVE: To study the expression of the Ces5a gene in the development of the rat testis. METHODS: Using RT-PCR, Western blot, immunohistochemistry and HE staining, we determined the mRNA transcription level, protein expression and localization of the Ces5a gene in the testes of three litters of rats at different postnatal (PN) days. RESULTS: The expression of Ces5a mRNA was found in the testis tissue of the rats at 2-65 PN days, low at 2-12 days, decreased to the lowest level at 14-16 days (P < 0.05), but significantly increased at 20-35 days (P < 0.05), and elevated to the highest level at 40-65 days (P < 0.05). The expression of the Ces5a protein was also observed in the testis tissue of the rats at 2-65 PN, low at 2-12 days, with no significant change at 14-16 days (P > 0.05), but markedly increased at 20-35 days (P < 0.05), and again with no significant change at 40-65 days (P > 0.05). The Ces5a protein was expressed in the spermatogonia, spermatocytes and round sperm cells. CONCLUSIONS: The Ces5a gene may be involved in the proliferation and meiosis of rat spermatogonia and play a special role in round spermatogenesis and sperm deformation.


Assuntos
Carboxilesterase/genética , Espermatogênese , Testículo/enzimologia , Animais , Masculino , Ratos , Espermatócitos , Espermatogônias , Espermatozoides , Testículo/crescimento & desenvolvimento
7.
Huan Jing Ke Xue ; 39(5): 2351-2359, 2018 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965536

RESUMO

In order to explore the effects of different amounts of biochar applied in purple paddy soil on greenhouse gas (GHG) emissions, potted experiments using a static opaque chamber and gas chromatography method were used to study the regulations and influences of biochar on soil greenhouse gas emission using five treatments:no fertilizer (CK), conventional fertilization (NPK), 10 t ·hm-2 biochar+NPK (LBC), 20 t ·hm-2 biochar+NPK (MBC), and 40 t ·hm-2 biochar+NPK (HBC). ① Soil CH4 emission flux reduced significantly with all biochar application treatments; the emission flux followed the order, from large to small, of NPK > CK > LBC > MBC > HBC. The CH4 emission flux of each treatment showed a single peak curve, and the peak value was mainly concentrated in the late growth stage of the paddy cropland. During the entire observation period, the emission flux of CH4 was between -0.05 mg ·(m2 ·h)-1 and 47.34 mg ·(m2 ·h)-1. The CO2 emission flux of each treatment was complicated and ranged from 32.95 mg ·(m2 ·h)-1 to 1350.88 mg ·(m2 ·h)-1. The CO2 emission flux of the LBC and MBC treatments showed bimodal curves, and the CO2 emission flux of other treatments showed single peak curves. In addition, all biochar treatments delayed the peak time of the CO2 emission flux. The N2O emission flux of each treatment ranged from -309.39 to 895.48 µg ·(m2 ·h)-1, and the N2O emission flux of the LBC treatment showed a bimodal curve, while other treatments showed single peak curves. ② Compared with the CK treatment, biochar treatment can significantly reduce the cumulative emissions of CH4 and promote the cumulative emissions of CO2 and N2O. The average amount of CH4 cumulative emissions followed the order CK > LBC > MBC > HBC, while the average amount of CO2 cumulative emissions followed LBC > MBC > HBC > CK, and the average amount of N2O cumulative emissions followed HBC > MBC≈LBC > CK. Compared with conventional fertilization treatment, different application rates of biochar addition significantly reduced CH4 and CO2 emissions. As more biochar was added, CH4 and CO2 cumulative emissions were lower. Although the regulation of N2O cumulative emissions on biochar addition was not obvious, the application of nitrogen fertilizer could promote the emission flux of N2O to some extent. ③ Over the time scale of 100 years, the integrated global warming potentials (GWP) of CH4 and N2O emission under different biochar treatment were decreased significantly, indicating that biochar combined with chemical fertilizer is an effective GHG emission reduction measure.


Assuntos
Carvão Vegetal , Gases de Efeito Estufa/análise , Solo/química , Agricultura , Dióxido de Carbono/análise , Fertilizantes , Metano/análise , Óxido Nitroso/análise , Oryza
8.
J Pharm Biomed Anal ; 159: 217-223, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30007177

RESUMO

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide. The discovery of new anticancer compounds is of great significance. GG-8-6, cyclo-(Val1-Leu2-Pro3-Ile4-Leu5-Leu6-Leu7-Val8-Leu9), a new synthetic cyclic peptide, might be a potential candidate for developing new anti-HCC drugs. GG-8-6 shares no structural homology to current anti-HCC drugs. Therefore, it was necessary to develop a quantitative method for the determination of GG-8-6 in vivo. Herein, a simple, specific and sensitive liquid chromatographic method with tandem mass spectrometric detection (LC-MS/MS) was developed and validated for the analysis of GG-8-6 in rat plasma. GG-8-6 and the internal standard (IS), A6, cyclo-(Val1-Leu2-Pro3-Ala4-Leu5-Leu6-Leu7-Val8-Leu9), were extracted from rat plasma by ethyl acetate. Chromatographic separation was performed on an Agilent Eclipse XDB-C18 column (4.6 × 150 mm, 5 µm) with a mobile phase consisting of acetonitrile-water containing 0.1% formic acid (90:10, v/v) with isocratic elution at a flow rate of 0.5 mL/min for 8.0 min. Multiple reaction monitoring (MRM) mode was performed with ion pairs of m/z: 974.8 → 861.8 for GG-8-6 and 932.7 → 819.8 for A6. The selectivity, matrix effects, recovery, intra- and inter-day precision and accuracy were validated with acceptable results in accordance with the US Food and Drug Administration guidelines. The calibration curve was linear (r2 > 0.99) over a concentration range of 1-1000 ng/mL with a lower limit of quantification (LLOQ) of 1 ng/mL. The method was successfully applied to the pharmacokinetic study of GG-8-6 in rats.


Assuntos
Peptídeos Cíclicos/sangue , Peptídeos Cíclicos/farmacocinética , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida/métodos , Cromatografia Líquida/normas , Cristalografia por Raios X/métodos , Cristalografia por Raios X/normas , Masculino , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem/normas
9.
Ying Yong Sheng Tai Xue Bao ; 29(5): 1535-1541, 2018 May.
Artigo em Chinês | MEDLINE | ID: mdl-29797886

RESUMO

Carbon (C), nitrogen (N) and phosphorus (P) contents and ecological stoichiometry and their correlations of litter and soil along 1500-1900 m on Wugong Mountain meadow were studied. The results showed that litter C, N and P contents varied in the range of 397.5-458.24, 11.59-17.12, 1.05-2.19 mg·g-1, respectively. Litter C content decreased, and the contents of N and P decreased first and then increased with the increases of altitude. Soil C, N and P contents varied in the range of 51.64-80.01, 3.30-4.77, 0.44-1.09 mg·g-1, respectively. Soil C, N and P contents first increased and then decreased with the increases of altitude. However, soil P varied much less along the altitude gradient. Litter C:N, C:P and N:P varied in the range of 24.73-40.36, 203.65-463.08, 7.16-13.80, respectively, and first increased but then decreased with altitude. Soil C:N, C:P and N:P were 14.95-16.95, 56.87-162.52, 3.69-10.58, respectively. Soil C:N changed little with altitude. Soil C:P and N:P first increased and then decreased with increa-sing altitude, with the maximum presented at 1600-1700 m. Changes in soil C, N and P contents differed between litter and soil on Wugong Mountain meadow. The mean C, N and P contents as well as C:N, C:P and N:P in litter were higher than those in soil.


Assuntos
Pradaria , Solo/química , Altitude , Carbono , China , Ecologia , Nitrogênio , Fósforo
10.
Cell Mol Neurobiol ; 36(5): 745-53, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26306919

RESUMO

The blood-brain barrier (BBB) is formed by brain endothelial cells, and decreased BBB integrity contributes to vasogenic cerebral edema and increased mortality after stroke. In the present study, we investigated the protective effect of perampanel, an orally active noncompetitive AMPA receptor antagonist, on BBB permeability in an in vitro ischemia model in murine brain endothelial cells (mBECs). The results showed that perampanel significantly attenuated oxygen glucose deprivation (OGD)-induced loss of cell viability, release of lactate dehydrogenase, and apoptotic cell death in a dose-dependent manner. Perampanel treatment did not alter the expression and surface distribution of various glutamate receptors. Furthermore, the results of calcium imaging showed that perampanel had no effect on OGD-induced increase in intracellular Ca(2+) concentrations. Treatment with perampanel markedly reduced the paracellular permeability of mBECs after OGD in different time points, as measured by transepithelial electrical resistance assay. In addition, the expression of claudin-5 at protein level, but not at mRNA level, was increased by perampanel treatment after OGD. Knockdown of claudin-5 partially prevented perampanel-induced protection in cell viability and BBB integrity in OGD-injured mBECs. These data show that the noncompetitive AMPA receptor antagonist perampanel affords protection against ischemic stroke through caludin-5 mediated regulation of BBB permeability.


Assuntos
Permeabilidade da Membrana Celular , Claudina-5/metabolismo , Células Endoteliais/efeitos dos fármacos , Isquemia/metabolismo , Piridonas/farmacologia , Receptores de AMPA/antagonistas & inibidores , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/metabolismo , Edema Encefálico/metabolismo , Células Cultivadas , Células Endoteliais/metabolismo , Glucose/metabolismo , Camundongos Endogâmicos C57BL , Nitrilas , Oxigênio/metabolismo , Acidente Vascular Cerebral/metabolismo
11.
Cell Mol Neurobiol ; 36(7): 1077-86, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26620051

RESUMO

Oxidative stress-induced cell damage is involved in many neurological diseases. Interferon regulatory factor 6 (IRF6), a member of the IRF family of transcription factors, is required for the differentiation of skin, breast epithelium, and oral epithelium. However, the regulation and function of IRF6 in central nervous system remain unknown. This study aimed to investigate the role of IRF6 in hydrogen peroxide (H2O2)-induced oxidative neuronal injury in HT22 mouse hippocampal cells. Treatment with H2O2 significantly increased the expression of IRF6 at both mRNA and protein levels, and knockdown of IRF6 using specific small interfering RNA reduced H2O2-induced cytotoxicity, as evidenced by increased cell viability and decreased apoptosis. Knockdown of IRF6 attenuated intracellular reactive oxygen species (ROS) generation and lipid peroxidation, and also preserved endogenous antioxidant enzyme activities. The inhibitory effect of IRF6 knockdown on mitochondrial dysfunction was demonstrated by reduced mitochondrial oxidative level, preserved mitochondrial membrane potential (MMP) and ATP generation, as well as attenuated mitochondrial swelling. In addition, down-regulation of IRF6 inhibited the activation of mitochondrial apoptotic factors, whereas IRF6 knockdown together with caspase inhibitors had no extra effect on cell viability and LDH release. These results suggest that knockdown of IRF6 has protective effects against H2O2-induced oxidative stress by reducing ROS accumulation and apoptosis, and these protective effects are dependent on preservation of mitochondrial function.


Assuntos
Peróxido de Hidrogênio/farmacologia , Fatores Reguladores de Interferon/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/metabolismo , Regulação para Baixo , Técnicas de Silenciamento de Genes/métodos , Fatores Reguladores de Interferon/genética , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Mitocôndrias/metabolismo , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo
12.
Genet Test Mol Biomarkers ; 19(4): 198-202, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25658980

RESUMO

Previous studies have demonstrated that miR-34 family members are abnormally expressed in gastric cancer. Overexpression of the miR-34 family suppresses gastric carcinogenesis, whereas downregulation of the miR-34 family promotes tumorigenesis. p53 can bind to the promoter region of miR-34b/c, leading to an increase of miR-34b/c expression. Recently, a variant in the promoter region of pri-miR-34b/c (rs4938723) has been discovered, with the function of altering the binding efficiency of transcription factor GATA. The purpose of this study was to examine the role of the miR-34b/c rs4938723 and TP53 Arg72Pro polymorphisms in the susceptibility of gastric cancer. We analyzed the distribution of the two polymorphisms in 197 patients with gastric cancer and 289 age-, gender-, ethnicity-, and living area-matched controls using polymerase chain reaction-restriction fragment length polymorphism and DNA direct sequencing. We found that the CT and CT/CC genotypes of the miR-34b/c rs4938723 were associated with a significantly decreased risk of gastric cancer compared with the TT genotype (CT vs. TT: odds ratio [OR]=0.66; 95% confidence interval [95% CI], 0.45-0.97; and CT/CC vs. TT: OR=0.67; 95% CI, 0.47-0.97, respectively). Combined analysis showed that subjects carrying the miR-34b/c rs4938723 CT/CC and TP53 CG/CC genotypes had a 0.62-fold decreased risk to develop gastric cancer compared with subjects carrying the miR-34b/c rs4938723 TT and TP53 CG/CC genotypes (OR=0.62; 95% CI, 0.40-0.96). These findings suggest that the miR-34b/c rs4938723 may individually and jointly have a protective effect on the risk of gastric risk.


Assuntos
MicroRNAs/genética , Polimorfismo de Fragmento de Restrição , Neoplasias Gástricas/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína Supressora de Tumor p53/genética
13.
Tumour Biol ; 35(1): 831-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23975373

RESUMO

Growing evidence has indicated that polymorphism present in the miRNA binding site of target gene can alter the ability of miRNAs to bind its target gene and modulate the development and progression of cancer. We aimed to investigate the association between let-7 KRAS rs712 polymorphism and the risk of colorectal cancer (CRC). The let-7 KRAS rs712 was analyzed in a case-control study, including 339 CRC patients and 313 age- and sex-matched controls; the relationship between the polymorphism and the clinicopathological features of CRC was also examined. Individuals carrying the let-7 KRAS rs712 TT genotype and T allele had an increased risk of developing CRC (TT vs. GG, adjusted OR = 2.18; 95% CI, 1.00-4.77; T vs. G, adjusted OR = 1.50; 95% CI, 1.15-1.96). Stratified analyses revealed that CRC patients with the let-7 KRAS rs712 TT genotype were more likely to have clinical stage III or IV disease (OR = 3.29, 95% CI, 1.32-8.20) and distant metastasis (OR = 4.70, 95% CI, 1.81-12.25). These findings provide evidence that the let-7 KRAS rs712 polymorphism may play crucial roles in the etiology of CRC.


Assuntos
Neoplasias Colorretais/genética , Predisposição Genética para Doença , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Idoso , Alelos , Estudos de Casos e Controles , Neoplasias Colorretais/patologia , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Razão de Chances , Proteínas Proto-Oncogênicas p21(ras) , Risco , Carga Tumoral
14.
Fam Cancer ; 13(1): 93-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23996697

RESUMO

Nasopharyngeal carcinoma (NPC) is characterized by its highly invasive and metastatic features. Therefore, screening genetic biomarkers of NPC to achieve early diagnose would be of great value for NPC therapy. Single nucleotide polymorphisms in let-7 miRNA binding site in 3' untranslated region of KRAS mRNA have been found to be associated with various cancer risks. In this study, we genotyped the frequency of KRAS rs712 to test its effect on NPC risk in a hospital-based case-control study in a Chinese population, with 188 histologically confirmed NPC patients and 356 cancer-free controls, using polymerase chain reaction-restriction fragment length polymorphism assay. There was no significant difference in the genotype and allele frequencies of the rs712 polymorphism between the NPC patients and the control group (GT vs. GG, OR 0.83, 95% CI 0.57-1.21; TT vs. GG, OR 1.27, 95% CI 0.58-2.75). Our data suggest that the KRAS rs712 polymorphism in let-7 miRNA binding site has no association with NPC risk. Further experiments with larger sample size or other polymorphism sites are needed to verify the result, especially in different ethnic groups.


Assuntos
MicroRNAs/genética , Neoplasias Nasofaríngeas/genética , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Regiões 3' não Traduzidas , Adulto , Povo Asiático/genética , Sítios de Ligação , Carcinoma , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Proteínas ras/metabolismo
15.
Ying Yong Sheng Tai Xue Bao ; 24(4): 1094-100, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23898670

RESUMO

Taking the long-term reforestation experimental base established in a severely degraded sub-tropical hilly red soil region in Taihe County of Jiangxi Province in 1991 as the object, this paper studied the changes of soil nutrients and microbial communities after 19 years reforestation of Pinus elliottii forest, Liquidambarformosana forest, and P. elliotti-L. formosana forest, with the naturally restored grassland as the control. The soil organic carbon content in the L. formosana and P. elliottii-L. formosana forests (15.16+/-3.53 and 16.42+/-0.49 g kg-1, respectively) was significantly higher than that in the control (9.30+/-1.13 g kg-1), the soil total phosphorus content was in the order of the control (0.30+/-0.02 g kg-1) > P. elliottii-L. formosana forest (0.22+/-0.04 g kg-1 ) > L. formosana forest (0.14+/-0.01 g kg-1 ), while the soil available phosphorus content was 1.66+/-0.02 mg kg-1 in L. formosana forest, 2.47+/-0. 27 mg kg- in P. elliottii-L. formosana forest, and 1. 15+/-0.71 mg kg-1 in P. elliottii forest, being significantly higher than that in the control (0.01+/-0.00 mg kg-1). The total amounts of soil microbes, the amount and percentage of soil bacteria, and the amount of inorganic and organic phosphate-solubilizing microbes in L. formosana forest and P. elliottii-L. formosana forest were all significantly higher than those in P. elliottii forest and the control, while the amount and percentage of soil fungi and the percentage of soil actinomycetes in L. formosana forest and P. elliottii-L. formosana forest were significantly lower than those in the control. The soil organic carbon content was significantly positively correlated with the percentage of soil bactera, but negatively correlated with the percentage of soil fungi and actinomycetes, while the soil available phosphorus content was significantly positively correlated with the amount of organic phosphate-solubilizing microes, but not with the amount of inorganic phosphate-solubilizing microbes. It was suggested that L. formosana forest and P. elliottii-L. formosana forest could be the recommended reforestation models in sub-tropical degraded red soil region.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Desenvolvimento Vegetal , Microbiologia do Solo , Solo/química , Bactérias/crescimento & desenvolvimento , China , Monitoramento Ambiental , Árvores/crescimento & desenvolvimento , Clima Tropical
16.
Tumour Biol ; 34(5): 3159-63, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23729275

RESUMO

Recently, single nucleotide polymorphisms in let-7 miRNA binding site in 3' untranslated region (UTR) of KRAS mRNA have been found to be associated with the cancer risk. In this study, we genotyped the frequency of KRAS rs712 to test its effect on gastric cancer (GC) risk in a hospital-based case-control study in a Chinese population, with 181 histologically confirmed GC patients and 674 cancer-free controls, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. The TT genotype of rs712 was associated with an increased risk of GC when taking GG genotype as a reference (adjusted odds ratio (OR) = 3.05, 95 % confidence interval (CI), 1.53-6.08). Similarly, the T allele of rs712 was associated with a statistically significant increase in susceptibility compared with G allele (adjusted OR = 1.44, 95 % CI, 1.10-1.90). Our data demonstrated that the T allele of the let-7 binding site polymorphism rs712 in KRAS 3' UTR was associated with a significantly increased risk of GC, suggesting that the KRAS rs712 polymorphism may be a genetic marker for the development of GC.


Assuntos
MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas/genética , Neoplasias Gástricas/genética , Proteínas ras/genética , Regiões 3' não Traduzidas , Adulto , Idoso , Sítios de Ligação , Estudos de Casos e Controles , China , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas p21(ras) , Fatores de Risco
17.
Ying Yong Sheng Tai Xue Bao ; 23(2): 468-74, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22586974

RESUMO

A 9-year observation was conducted at the experimental plots in the Citrus reticulata plantation in Jiangxi Provincial Eco-Technology Park to study the eco-hydrological characteristics and soil conservation benefits of the plantation on slope red soil. Seven treatments were designed and monitored over nine years. The average flow and the rate of sediment for the seven treatments were reduced by 78.5% and 77.2%, respectively. The reduction rates were the highest in treatments band coverage of Paspalum natatu, whole coverage of P. natatu, and level terrace with grass on ridge, with the values of 94.8%, 94.3% and 92.5%, respectively, followed by in treatment intercropping Glycine max (66.0%) and Raphanus sativus (77.5%), with horizontal planting being better than vertical planting, and the lowest in treatment without understory vegetation (33.1%). The observations on the precipitation redistribution of 43 rainfall events with a mean precipitation of 20.07 mm in 2009-2010 showed that the throughfall, stemflow, and canopy interception were 9.15, 4.72 and 6.20 mm, accounting for 44.7%, 25.7% and 29.6% of the precipitation, respectively. The throughfall and stemflow tended to increase with increasing precipitation. There was a significant liner negative correlation between the canopy interception rate and the precipitation when the rainfall was less than 10 mm, but no significant correlation when the rainfall was greater than 10 mm. The water holding rate of C. reticulata litters was logarithmically correlated with water soaking time, and the maximum water holding rate was 326%. It was considered that rational allocation of understory vegetation played an important role in the soil and water conservation of citrus orchard on slope red soil.


Assuntos
Citrus/crescimento & desenvolvimento , Conservação dos Recursos Naturais , Ecossistema , Solo/análise , Água/análise , China , Monitoramento Ambiental
18.
Clin Biochem ; 45(4-5): 285-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22222605

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the effects of interleukin-13 (IL-13) polymorphisms on the risk of asthma using a meta-analysis. DESIGN AND METHODS: Fifteen publications were identified by searching Pubmed, Embase, ISI, OVID, and EBSCO databases. Odds ratios with corresponding 95% confidence intervals were computed to estimate the association between IL-13 polymorphisms and risk of asthma. RESULTS: The polymorphisms of R130Q (rs20541) and -1112C/T (rs1800925) in IL-13 gene were associated with significantly increased risks of asthma in overall analyses. Subgroup analyses showed that the elevated risks occurred in adult-onset asthma, Caucasians, and high quality studies. CONCLUSIONS: This meta-analysis provides evidence that the R130Q and -1112C/T polymorphisms in IL-13 are risk factors for asthma.


Assuntos
Asma/genética , Interleucina-13/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idade de Início , Substituição de Aminoácidos , Criança , Estudos de Associação Genética , Humanos , Regiões Promotoras Genéticas , Fatores de Risco , População Branca
19.
Ying Yong Sheng Tai Xue Bao ; 22(10): 2567-73, 2011 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-22263459

RESUMO

Taking the typical forest types Pinus elliottii var. elliotttii, Araucaria cunninghamii, and Agathis australis in southern Queensland of Australia as test objects, an investigation was made on the soil soluble organic carbon (SOC) and nitrogen (SON), microbial biomass C (MBC) and N (MBN), and enzyme activities, aimed to understand the effects of forest type on soil quality. In the three forests, soil SOC content was 552-1154 mg kg(-1), soil SON content was 20.11-57.32 mg kg(-1), soil MBC was 42-149 mg kg(-1), soil MBN was 7-35 mg kg(-1), soil chitinase (CAS) activity was 2.96-7.63 microg g(-1) h(-1), soil leucine aminopeptidase (LAP) activity was 0.18-0.46 microg g(-1) d(-1), soil acid phosphatase (ACP) activity was 16.5-29.6 microg g(-1) h(-1), soil alkaline phosphatase (AKP) activity was 0.79-3.42 microg g(-1) h(-1), and soil beta-glucosidase (BG) activity was 3.71-9.93 microg g(-1) h(-1). There was a significant correlation between soil MBC and MBN. Soil SOC content and soil CAS and LAP activities decreased in the order of P. elliottii > A. cunninghamii > A. australis, soil SON content decreased in the order of A. cunninghamii > A. australis > P. elliottii and was significantly higher in A. cunninghamii than in P. elliottii forest (P < 0.05), soil MBC and MBN and AKP activity decreased in the order of A. australis > P. elliottii > A. cunninghamii, and soil ACP and BG activities decreased in the order of P. elliottii > A. australis > A. cunninghamii. Among the test soil biochemical factors, soil MBC, MBN, SON, and LAP had greater effects on the soil quality under the test forest types.


Assuntos
Enzimas/metabolismo , Compostos Orgânicos/análise , Microbiologia do Solo , Solo/análise , Árvores/classificação , Fosfatase Ácida/metabolismo , Biomassa , Quitinases/metabolismo , Cunninghamia/crescimento & desenvolvimento , Leucil Aminopeptidase/metabolismo , Pinus/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento
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