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1.
Ying Yong Sheng Tai Xue Bao ; 34(7): 1871-1882, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37694471

RESUMEN

To explore the groundwater recharge rate and soybean growth dynamics under different groundwater depths, we conducted a field experiment with four groundwater depth treatments (1 m, D1; 2 m, D2; 3 m, D3; 4 m, D4) through the groundwater simulation system in 2021 and 2022 and explored the relationships between groundwater depth and groundwater recharge, irrigation, growth dynamics of soybean plants, and yield. We used the Logistic regression model to simulate the dynamics of soybean growth indices, including plant height, leaf area index, and dry matter accumulation. The results showed that compared with D1 treatment, the amount of groundwater recharge under D2, D3, and D4 treatments decreased by 81.1%, 96.8%, 97.5% and 80.7%, 96.7%, 97.3% in the two years, respectively. The groundwater in D1 treatment could meet water needs of soybean throughout the whole growth period, except that irrigation was needed in the sowing stage. The amount of irrigation under D1 treatment was decreased by 91.7%, 93.0%, 94.2%, and 90.9%, 92.9%, 94.0% in the two years, respectively, compared with D2, D3, D4 treatments. Among the four treatments, D1 treatment took the shortest time for entering the rapid growth stage and reach the maximum growth rate, which had the highest maximum growth rate. At the mature stage of soybean, the dry matter distribution ratio of stem in D1 treatment was the highest. D1 treatment promoted the translocation of post-flowering assimilates in soybean, and its post-flowering assimilate contribution to seeds increased by 15.5%, 16.2%, 32.6% and 45.5%, 48.7%, 63.3% in the two years, respectively, compared with D2, D3, D4 treatments. D1 treatment had the highest plant height, leaf area index, and dry matter accumulation, follo-wed by D4 treatment, while D3 treatment had the lowest. Soybean yield, number of pods per plant, number of grains per plant, and 100-grain weight all decreased and then increased with increasing groundwater depth, following an order of D1>D4>D2>D3. Soybean yield was significantly positively correlated with groundwater recharge, which was positively correlated with plant height, leaf area index, and dry matter accumulation. Our results indicated that the D1 treatment with adequate groundwater recharge increased plant height, leaf area index, and dry matter accumulation, coordinated the distribution and translocation of dry matter among all plant parts in the late soybean growth period, and ultimately achieved the highest yield. When groundwater depth was deep (D4), groundwater recharge was small. In such case, the growth and development status and yield of soybean could also reach a high level if there was sufficient water supply.


Asunto(s)
Glycine max , Agua Subterránea , Abastecimiento de Agua , China , Simulación por Computador
2.
Artículo en Inglés | MEDLINE | ID: mdl-31540337

RESUMEN

To improve the biodegradation efficiency of fluoroquinolone antibiotics during sewage treatment, fluoroquinolone aerobic, anaerobic and facultative degrading enzymes for fluoroquinolone degradation were modified by molecular docking and homology modelling. First, amino acid residues of the binding sites of degrading enzymes for the target fluoroquinolones ciprofloxacin (CIP), norfloxacin (NOR) and ofloxacin (OFL) were analysed by the molecular docking method. The hydrophobic amino acid residues within 5 Å of the target fluoroquinolone molecules were selected as the modification sites. The hydrophobic amino acid residues at the modified sites were replaced by the hydrophilic amino acid residues, and 150 amino acid sequence modification schemes of the degrading enzymes were designed. Subsequently, a reconstruction scheme of the degrading enzyme amino acid sequence reconstruction scheme was submitted to the SWISS-MODEL server and a selected homology modelling method was used to build a new structure of the degrading enzyme. At the same time, the binding affinities between the novel degrading enzymes and the target fluoroquinolones (represented by the docking scoring function) were evaluated by the molecular docking method. It was found that the novel enzymes can simultaneously improve the binding affinities for the three target fluoroquinolones, and the degradation ability of the six modification schemes was increased by more than 50% at the same time. Among the novel enzymes, the affinity effect of the novel anaerobic enzyme (6-1) with CIP, NOR and OFL was significantly increased, with increases of 129.24%, 165.06% and 169.59%, respectively, followed by the facultative enzyme and aerobic enzyme. In addition, the designed degrading enzymes had certain selectivity for the degradation of the target quinolone. Among the novel enzymes, the binding affinities of the novel anaerobic enzyme (6-3) and CIP, the novel aerobic enzyme (3-6) and NOR, and the novel facultative enzyme (13-6) and OFL were increased by 149.71%, 178.57% and 297.12% respectively. Calculations using the Gaussian09 software revealed that the degradation reaction barrier of the novel degrading enzyme (7-1) and CIP NOR and OFL decreased by 37.65 kcal·mol-1, 6.28 kcal·mol-1 and 6.28 kcal·mol-1, respectively, which would result in efficient degradation of the target fluoroquinolone molecules. By analysing the binding affinity of the degrading enzymes before and after the modification with methanol, it was further speculated that the degradation effect of the modified aerobic degrading enzymes on organic matter was lower than that before the modification, and the increase or decrease in the degradation effect was less than 10%. The mechanism analysis found that the interaction between the modified amino acid residues of the degrading enzymes and the fluoroquinolone molecules increased. The average distance between the amino acid residues and the fluoroquinolone molecules represented a comprehensive affinity effect, and its value was positively correlated with the degradation effect of the novel degrading enzymes.


Asunto(s)
Antibacterianos/metabolismo , Ciprofloxacina/metabolismo , Modelos Moleculares , Norfloxacino/metabolismo , Ofloxacino/metabolismo , Aminoácidos/metabolismo , Antibacterianos/química , Sitios de Unión , Biodegradación Ambiental , Ciprofloxacina/química , Norfloxacino/química , Ofloxacino/química
3.
Ying Yong Sheng Tai Xue Bao ; 29(1): 113-124, 2018 Jan.
Artículo en Chino | MEDLINE | ID: mdl-29692019

RESUMEN

In order to investigate the effect of different colored plastic film mulching and planting density on spring maize dry matter accumulation and yield in the rain-fed area of the Northeast China, a complete combination field experiment which was comprised by three types of mulching (non-mulching, transparent plastic film mulching and black plastic film mulching) and five densities (60000, 67500, 75000, 82500 and 90000 plants·hm-2), was conducted to analyze the water and heat effect, dry matter accumulation and yield of spring maize (Liangyu 99). The results showed that, compared with the other mulching treatments, the black plastic film mulching treatment significantly increased the maize dry matter accumulation and maize biomass by 3.2%-8.2%. In mature stage, the biomass increased firstly and then decreased with the increasing plant density. When planting density was 82500 plants·hm-2, the biomass was the highest, which was 5.2%-28.3% higher than that of other plant density treatments. The mean soil temperature in prophase of transparent plastic film mulching treatment was 0.4-2.7 ℃ higher than that of other treatments, which accelerated the maize growth process and augmented the dry matter transportation amount (T), dry matter transportation efficiency (TE) and contribution rate of dry matter transportation to the grain yield (TC) of maize stalk and leaf. The T, TE, TC of leaf and leaf-stalk under 60000 plants·hm-2 treatment were the highest. The highest T, TE, TC of stalk were observed under 75000 plants·hm-2 treatment. In heading period, the water consumption and daily water consumption intensity of maize under the treatment of black film mulching were the largest, which were 9.4%-10.6% and 10.6%-24.5% higher than that of other mulching treatments, respectively. The highest water consumption and daily water consumption intensity were both obtained under 90000 plants·hm-2 treatment, which increased by 6.8%-15.7% and 7.0%-20.0% compared with other plant density treatments. The combination of black film mulching and density of 82500 plants·hm-2 significantly improved the water use efficiency of maize, which increased by 4.6%-40.9% compared with other treatments. In addition, it increased yield by 3.0%-39.7% compared with other treatments. At heading stage, the correlation between the dry matter amount of stalk and leaf and the yield and yield components was the biggest. Decreasing 1 kg·hm-2 dry matter amount of stalk and leaf would decrease the population yield by almost 0.79 kg·hm-2. Decreasing 10% dry matter amount of stalk and leaf would decrease the yield by almost 10%. Based on increasing plant density, black film mulching was beneficial for increasing the dry matter accumulation and improving grain yield and water use efficiency of spring maize.


Asunto(s)
Color , Plásticos , Zea mays/crecimiento & desarrollo , Agricultura , Biomasa , China , Producción de Cultivos , Lluvia , Suelo , Agua
4.
Asian Pac J Cancer Prev ; 15(7): 3001-4, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24815437

RESUMEN

Annexin A3 has been identified as a novel biomarker in different types of cancers. However, little is known about its clinical significances and and biological roles in gastric cancer. In this study, we assessed annexin A3 expression in 80 patients with gastric cancer and explore its correlation with prognosis Moreover, correlations with Ki-67, Bcl-2 and Bax were also investigated. Expression of annexin A3 was increased in gastric cancer compared with that in normal gastric tissues. Annexin A3 expression was significantly associated with tumor volume and TNM stage (p<0.05). and inversely correlation with prognosis of patients. More interestingly, expression of annexin A3 was positive correlated with Ki-67 and Bcl-2 expression. Our study showed annexin A3 might be a potential prognostic marker for gastric cancer and involved in tumorigenesis by regulating apoptosis and proliferation.


Asunto(s)
Anexina A3/biosíntesis , Apoptosis/genética , Proliferación Celular/genética , Neoplasias Gástricas/metabolismo , Anciano , Biomarcadores de Tumor/biosíntesis , Biomarcadores de Tumor/genética , Carcinogénesis/genética , Femenino , Humanos , Antígeno Ki-67/biosíntesis , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Adhesión en Parafina , Pronóstico , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Neoplasias Gástricas/genética , Neoplasias Gástricas/mortalidad , Proteína X Asociada a bcl-2/biosíntesis
5.
Med Oncol ; 30(1): 403, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23288725

RESUMEN

Expression of heparanase is associated with invasion, metastasis and angiogenesis of a variety of human cancers. However, the roles of heparanase in cervical cancer are not clear. The aim of this study is to determine whether up-regulation of heparanase expression can promote growth of cervical cancer in vitro and in vivo. Heparanase protein expression was analyzed in cervical cancer patients using immunohistochemistry. In addition, expression of heparanase was also examined in cervical cancer cell lines. A series of in vivo and in vitro assays was performed to elucidate the role of heparanase in tumor growth of cervical cancer. Positive rate of heparanase was 63.3 % (38/60) in cervical cancer patients by immunohistochemistry, and it was significantly correlated with tumor size and clinical stage (P < 0.05). Overexpression of heparanase inhibited apoptosis of cervical cancer cells. Moreover, ectopic overexpression of heparanase in cervical cancer cells promoted proliferation of cervical cancer cells in vitro and tumor growth in vivo. These results suggest that heparanase participates in tumor growth of cervical cancer by influencing the proliferation and apoptosis of cervical cancer cells, and heparanase could be used as an effective therapeutic target for cervical cancer.


Asunto(s)
Biomarcadores de Tumor/análisis , Glucuronidasa/biosíntesis , Neoplasias del Cuello Uterino/enzimología , Adulto , Animales , Apoptosis/fisiología , Western Blotting , Línea Celular Tumoral , Proliferación Celular , Femenino , Glucuronidasa/análisis , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Clasificación del Tumor , Estadificación de Neoplasias , Transfección , Regulación hacia Arriba , Neoplasias del Cuello Uterino/patología
6.
J Dig Dis ; 13(6): 304-9, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22624553

RESUMEN

OBJECTIVE: We aimed to determine the prevalence of eosinophilic esophagitis (EoE) and define its clinical and endoscopic characteristics in Chinese patients. METHODS: Esophageal specimens obtained from January 2006 to December 2010 in the First Affiliated Hospital of Sun Yat-sen University were reviewed, and the data on clinical characteristics and endoscopic findings of patients were obtained. Patients with eosinophils ≥15 per high power field (HPF) were identified as having EoE. RESULTS: A total of 12 patients met the criteria for EoE, establishing a prevalence of 0.34%. These patients presented with dysphagia (4/12, 33.3%), gastroesophageal reflux disease (GERD)-like symptoms (3/12, 25.0%), abdominal pain (3/12, 25.0%) and others (2/12, 16.7%). The most common endoscopic finding was plaques (5/12, 41.7%), and other findings were irregular Z-line (2/12, 16.7%), erosive esophagitis (2/12, 16.7%), white exudates (1/12, 8.3%), linear furrows (1/12, 8.3%), Schatzki ring (1/12, 8.3%), ulcers (1/12, 8.3%) and erythema (1/12, 8.3%). CONCLUSIONS: The prevalence of EoE was 0.34% in our patients. Clinicians should pay attention to patients manifested with dysphagia and GERD-like symptomes with endosopic findings of white exudates, plaques, Schatzki ring and linear furrows.


Asunto(s)
Esofagitis Eosinofílica/epidemiología , Adulto , Anciano , Biopsia , China/epidemiología , Trastornos de Deglución/epidemiología , Trastornos de Deglución/etiología , Esofagitis Eosinofílica/complicaciones , Esofagitis Eosinofílica/diagnóstico , Esofagitis Eosinofílica/terapia , Esofagoscopía , Esófago/patología , Femenino , Reflujo Gastroesofágico/epidemiología , Reflujo Gastroesofágico/etiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia
7.
PLoS One ; 7(4): e35754, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22540002

RESUMEN

Abnormal activation of the canonical Wnt signaling pathway has been implicated in carcinogenesis. Transcription of Wnt target genes is regulated by nuclear ß-catenin, whose over-expression is observed in Hepatocellular Carcinoma (HCC) tissue. Cyr61, a member of the CCN complex family of multifunctional proteins, is also found over-expressed in many types of tumor and plays dramatically different roles in tumorigenesis. In this study, we investigated the relationship between Cyr61 and ß-catenin in HCC. We found that while Cyr61 protein was not expressed at a detectable level in the liver tissue of healthy individuals, its expression level was elevated in the HCC and HCC adjacent tissues and was markedly increased in cancer-adjacent hepatic cirrhosis tissue. Over-expression of Cyr61 was positively correlated with increased levels of ß-catenin in human HCC samples. Activation of ß-catenin signaling elevated the mRNA level of Cyr61 in HepG2 cells, while inhibition of ß-catenin signaling reduced both mRNA and protein levels of Cyr61. We identified two TCF4-binding elements in the promoter region of human Cyr61 gene and demonstrated that ß-catenin/TCF4 complex specifically bound to the Cyr61 promoter in vivo and directly regulated its promoter activity. Furthermore, we found that over-expression of Cyr61 in HepG2 cells promoted the progression of HCC xenografts in SCID mice. These findings indicate that Cyr61 is a direct target of ß-catenin signaling in HCC and may play an important role in the progression of HCC.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Proteína 61 Rica en Cisteína/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animales , Carcinoma Hepatocelular/patología , Proteína 61 Rica en Cisteína/genética , Células HEK293 , Células Hep G2 , Humanos , Neoplasias Hepáticas/patología , Ratones , Regiones Promotoras Genéticas , Trasplante Heterólogo , Vía de Señalización Wnt
8.
Cancer Biol Ther ; 12(6): 539-48, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21750404

RESUMEN

Astrocyte elevated gene-1 (AEG-1) is overexpressed in several cancers and plays an important role in cancer progression. However, AEG-1 expression, biological function, and clinical significance in osteosarcoma have not been uncovered. Utilizing manipulated human osteosarcoma cell lines and osteosarcoma tissues, we found that increasing expression of AEG-1 enhanced osteosarcoma cell proliferation and invasion in vitro, and knockdown of AEG-1 significantly attenuated osteosarcoma cell malignancy. Moreover, AEG-1 was overexpressed in osteosarcoma tissues, and overexpression of AEG-1 was strongly associated with gender (p = 0.018), clinical stages (p < 0.001), classification (p < 0.001), metastasis (p = 0.013), differentiation (p < 0.001), and poor survival (p = 0.021). Mechanistic studies conducted in vitro and in vivo revealed that AEG-1-mediated carcinogenesis and invasiveness might be through upregulating MMP-2. Taken together, our data strongly suggest that AEG-1 plays a crucial role in osteosarcoma progression through MMP-2, and AEG-1 could be a useful biomarker for the prediction of osteosarcoma progression and prognosis.


Asunto(s)
Neoplasias Óseas/metabolismo , Moléculas de Adhesión Celular/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Osteosarcoma/metabolismo , Adulto , Neoplasias Óseas/mortalidad , Neoplasias Óseas/patología , Moléculas de Adhesión Celular/genética , Línea Celular Tumoral , Proliferación Celular , Femenino , Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Estimación de Kaplan-Meier , Masculino , Metaloproteinasa 2 de la Matriz/genética , Proteínas de la Membrana , Análisis Multivariante , Invasividad Neoplásica , Osteosarcoma/mortalidad , Osteosarcoma/patología , Pronóstico , Interferencia de ARN , Proteínas de Unión al ARN , Adulto Joven
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