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1.
World J Gastrointest Oncol ; 16(6): 2673-2682, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38994136

ABSTRACT

BACKGROUND: RAS, BRAF, and mismatch repair (MMR)/microsatellite instability (MSI) are crucial biomarkers recommended by clinical practice guidelines for colorectal cancer (CRC). However, their characteristics and influencing factors in Chinese patients have not been thoroughly described. AIM: To analyze the clinicopathological features of KRAS, NRAS, BRAF, and PIK3CA mutations and the DNA MMR status in CRC. METHODS: We enrolled 2271 Chinese CRC patients at the China-Japan Friendship Hospital. MMR proteins were tested using immunohistochemical analysis, and the KRAS/NRAS/BRAF/PIK3CA mutations were determined using quantitative polymerase chain reaction. Microsatellite status was determined using an MSI detection kit. Statistical analyses were conducted using SPSS software and logistic regression. RESULTS: The KRAS, NRAS, BRAF, and PIK3CA mutations were detected in 44.6%, 3.4%, 3.7%, and 3.9% of CRC patients, respectively. KRAS mutations were more likely to occur in patients with moderate-to-high differentiation. BRAF mutations were more likely to occur in patients with right-sided CRC, poorly differentiated, or no perineural invasion. Deficient MMR (dMMR) was detected in 7.9% of all patients and 16.8% of those with mucinous adenocarcinomas. KRAS, NRAS, BRAF, and PIK3CA mutations were detected in 29.6%, 1.1%, 8.1%, and 22.3% of patients with dMMR, respectively. The dMMR was more likely to occur in patients with a family history of CRC, aged < 50 years, right-sided CRC, poorly differentiated histology, no perineural invasion, and with carcinoma in situ, stage I, or stage II tumors. CONCLUSION: This study analyzed the molecular profiles of KRAS, NRAS, BRAF, PIK3CA, and MMR/MSI in CRC, identifying key influencing factors, with implications for clinical management of CRC.

2.
World J Psychiatry ; 13(6): 298-318, 2023 Jun 19.
Article in English | MEDLINE | ID: mdl-37383285

ABSTRACT

Psychiatrists require frequent contact with and treatment of patients with mental illnesses. Due to the influence of associative stigma, psychiatrists may also be targets of stigma. Occupational stigma warrants special consideration because it significantly affects psychiatrists' career advancement, well-being, and their patients' health. Given that there is no complete summary of this issue, this study reviewed the existing literature on psychiatrists' occupational stigma to clearly synthesize its concepts, measurement tools, and intervention strategies. Herein, we emphasize that psychiatrists' occupational stigma is a multifaceted concept that simultaneously encompasses physically, socially, and morally tainted aspects. Currently, standardized methods to specifically measure psychiatrists' occupational stigma are lacking. Interventions for psychiatrists' occupational stigma may consider the use of protest, contact, education, comprehensive and systematic methods, as well as the use of psychotherapeutic approaches. This review provides a theoretical basis for the development of relevant measurement tools and intervention practices. Overall, this review seeks to raise public awareness of psychiatrists' occupational stigma, thereby promoting psychiatric professionalism and reducing its stigma.

3.
World J Clin Cases ; 11(11): 2482-2488, 2023 Apr 16.
Article in English | MEDLINE | ID: mdl-37123316

ABSTRACT

BACKGROUND: Reports on perioperative anesthesia management in pediatric patients with difficult airways are scarce. In addition to relatively more difficulties in the technique of endotracheal intubation, the time for manipulation is restricted compared to adults. Securing the airways safely and avoiding the occurrence of hypoxemia in these patients are of significance. CASE SUMMARY: A 9-year-old boy with spastic cerebral palsy, severe malnutrition, thoracic scoliosis, thoracic and airway malformation, laryngomalacia, pneumonia, and epilepsy faced the risk of anesthesia during palliative surgery. After a thorough preoperative evaluation, a detailed scheme for anesthesia and a series of intubation tools were prepared by a team of anesthesiologists. Awake fiberoptic intubation is the widely accepted strategy for patients with anticipated difficult airways. Given the age and medical condition of the patient, we kept him sedated with spontaneous breathing during endotracheal intubation. The endotracheal intubation was completed on the second attempt after the failure of the first effort. Fortunately, the surgery was successful without postoperative complications. CONCLUSION: Dealing with difficult airways in the pediatric population, proper sedation allows time to intubate without interrupting spontaneous breathing. The appropriate endotracheal intubation method based on the patient's unique characteristics is the key factor in successful management of these rare cases.

4.
Huan Jing Ke Xue ; 43(7): 3523-3531, 2022 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-35791536

ABSTRACT

In order to propose pertinent suggestions regarding eutrophication control for Lake Hongze, we used monthly monitoring data from 2011 to 2020 to elucidate the spatiotemporal changing characteristics of eutrophic status and the relevant driving factors. As the main river entering Lake Hongze, River Huaihe experienced an increase in permanganate index and a decrease in TN in the last 10 years. Meanwhile, Secchi depth, TP, and permanganate index increased, whereas TN and Chl-a concentration decreased significantly in Lake Hongze. As a result, the eutrophic status TLI index of Lake Hongze declined over the past 10 years. The change trend of TLI in Lake Hongze differed spatially. As the main water passage of River Huaihe, the algal biomass was lower in the eastern region than that in the other two lake regions, regardless of the relatively high nutrient concentration, due to the short water retention time. Furthermore, the water quality of River Huaihe improved; thus, the TLI index decreased significantly in the eastern lake region. The northern region had a high coverage of aquatic vegetation, which not only reduced the concentration of water nutrients but also provided a habitat for zooplankton and fish, effectively inhibiting algal growth. Thus, the TLI index was lowest among the three lake areas and showed a downward trend over the last 10 years. In the western region, the algal biomass was the highest due to the intensification of phosphorus release from sediment in summer. Thus, the TLI index was the highest and had not improved in the past 10 years. There were also significant seasonal differences in the TLI of Lake Hongze, which was highest in summer, due to the relatively high algal biomass. Moreover, the algal biomass in summer was mainly affected by the concentration of nitrate. According to the spatiotemporal distribution characteristics of eutrophic status and the impacting factors in Lake Hongze, corresponding measures for eutrophication control should be taken for different seasons and lake areas.


Subject(s)
Environmental Monitoring , Eutrophication , Animals , Lakes , Phosphorus/analysis , Rivers
5.
Bioact Mater ; 17: 496-505, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35415293

ABSTRACT

This study aimed to investigate the long-term biocompatibility, safety, and degradation of the ultrathin nitrided iron bioresorbable scaffold (BRS) in vivo, encompassing the whole process of bioresorption in porcine coronary arteries. Fifty-two nitrided iron scaffolds (strut thickness of 70 µm) and 28 Vision Co-Cr stents were randomly implanted into coronary arteries of healthy mini-swine. The efficacy and safety of the nitrided iron scaffold were comparable with those of the Vision stentwithin 52 weeks after implantation. In addition, the long-term biocompatibility, safety, and bioresorption of the nitrided iron scaffold were evaluated by coronary angiography, optical coherence tomography, micro-computed tomography, scanning electron microscopy, energy dispersive spectrometry and histopathological evaluations at 4, 12, 26, 52 weeks and even at 7 years after implantation. In particular, a large number of struts were almost completely absorbed in situ at 7 years follow-up, which were first illustrated in this study. The lymphatic drainage pathway might serve as the potential clearance way of iron and its corrosion products.

6.
Ying Yong Sheng Tai Xue Bao ; 31(9): 3173-3186, 2020 Sep 15.
Article in Chinese | MEDLINE | ID: mdl-33345519

ABSTRACT

Clarifying the consumption of local natural capital stock and natural capital flow and its influencing factors can help alleviate the tension between the socio-economic development of the coastal zone, natural resources, and the ecological environment, and promote regional coordinated and sustainable development. Based on the two-dimensional and three-dimensional ecological footprint evaluation models, we analyzed the spatial and temporal variations of ecological footprint in the coastal zone of Zhejiang Province from 2006 to 2016, and explored the regional natural capital stock and capital flow occupancy based on footprint depth and footprint width. We analyzed the spatial and temporal heterogeneity of its influencing factors using a geographically and temporally weighted regression model. The results showed that ecological crisis in the coastal zone of Zhejiang Province deepened during the study period. The average per capita ecological deficit was 3.5 hm2·cap-1, and the per capita ecological deficit increased by 15.5%. Among them, the contribution of energy consumption account to the per capita ecological footprint was greater than that of the biological resources account. The per capita ecological footprint of each county showed an increasing trend, with significant spatial variation. The coastal zone of Zhejiang Province mainly consumed the natural capital stock, with a significant inhibitory effect on the renewal of natural capital flows. The consumption of natural capital stock was 14.87 times that of capital flow in 2016. Urban scale, economic development level, and people's income level had positive impacts on the ecological footprint of coastal counties of Zhejiang Province, while fishery production had negative effect on the ecological footprints, with transition trend to a positive one. The influence mechanism of the three factors had significant spatial and temporal differentiation.


Subject(s)
Conservation of Natural Resources , Economic Development , China , Humans , Models, Theoretical , Sustainable Development
7.
Cell Signal ; 72: 109650, 2020 08.
Article in English | MEDLINE | ID: mdl-32320856

ABSTRACT

Epithelial-mesenchymal transition (EMT), a pivotal event during cancer progression such as relapse and metastasis, is positively correlated with the stemness potency of tumor cells. Our previous study showed that miR-296-5p attenuated EMT program of hepatocellular carcinoma cells (HCC) through NRG1/ERBB2/ERBB3 signaling. In the present study, we uncovered that miR-296-5p was able to inhibit the stemness potency of HCC by decreasing the number and size of tumorspheres, downregulating the expression of CSC biomarkers and hampering the ability of tumorigenesis in NOD/SCID mice. Brahma-related gene-1 (Brg1), as the target protein of miR-296-5p detected by bioinformatics methods, activates a series of downstream cascades through directly binding to Sall4 promoter and enhancing Sall4 transcription. Importantly, the higher expressions of Brg1 and Sall4 in tumor tissues of HCC patients suggest poorer prognoses after surgical extraction. In conclusion, miR-296-5p exerts an inhibitory effect on stemness potency of HCC cells via Brg1/Sall4 axis.


Subject(s)
Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/pathology , DNA Helicases/metabolism , Liver Neoplasms/genetics , Liver Neoplasms/pathology , MicroRNAs/metabolism , Neoplastic Stem Cells/metabolism , Nuclear Proteins/metabolism , Transcription Factors/metabolism , Animals , Base Sequence , Cell Line, Tumor , Down-Regulation/genetics , Epithelial Cell Adhesion Molecule/metabolism , Gene Expression Regulation, Neoplastic , Humans , Mice, Inbred NOD , Mice, SCID , MicroRNAs/genetics , Neoplastic Stem Cells/pathology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction , Thy-1 Antigens/metabolism
8.
Biomed Chromatogr ; 34(5): e4814, 2020 May.
Article in English | MEDLINE | ID: mdl-32100317

ABSTRACT

Lu-Jiao Fang (LJF), a traditional Chinese medicine prescription, can improve the cardiac function of chronic heart failure (CHF) patients; however, knowledge about the cardiac distribution of LJF, especially in CHF animal models, is rather limited. This work aimed to explore the cardiac distribution of LJF in pressure overload-induced CHF rats at the last gavage administration of LJF after 30 weeks of treatment. LC-MS/MS methods for analyzing nine active components (i.e. loganin, hesperidin, epimedin C, icariin, psoralen, isopsoralen, baohuoside I, morroniside and specnuezhenide) of LJF in cardiac tissue samples were established, and the components were then analyzed in left ventricular wall (LVW) and right ventricular wall (RVW) in parallel at same time point postdose for three dose groups. The results showed that most analytical component levels in LVW (hypertrophic myocardium) were only 39-74% of those in RVW (normal myocardium); however, psoralen and isopsoralen levels in LVW were equal to or even greater than the levels in RVW, suggesting that the hypertrophic myocardium tissue affinity of psoralen and isopsoralen might overcome the negative effect of decreased blood flow on distribution. This study indicated that the pathological state may influence drug distribution, and the efficacy of psoralen and isopsoralen for improving CHF deserves further investigation.


Subject(s)
Cardiomyopathy, Hypertrophic/drug therapy , Drugs, Chinese Herbal/administration & dosage , Drugs, Chinese Herbal/chemistry , Heart Failure/drug therapy , Animals , Chromatography, High Pressure Liquid/methods , Heart/drug effects , Humans , Male , Rats , Rats, Wistar , Tandem Mass Spectrometry/methods
9.
Yi Chuan ; 41(9): 836-844, 2019 Sep 20.
Article in Chinese | MEDLINE | ID: mdl-31549682

ABSTRACT

Wheat is one of the main food crops and widely grown in the world. It feeds more than 35% of the world's population. Obtaining high-quality genome sequences of wheat is important for its basic and breeding researches. However, the large and complex genome of wheat once led to its genome sequencing as an "impossible task". Recently, with the development of high-throughput sequencing and assembly technology, many wheat genome sequences have been released, and their sequencing and assembly quality is being improved continuously. In the last two years, five wheat reference genomes with different ploidy levels have been published, including two diploid ancestors Triticum urartu (AA) and Aegilops tauschii (DD), wild and cultivated tetraploid wheat T. turgidum ssp. dicoccoides (BBAA) and hexaploid wheat T. aestivum (BBAADD). Among them, the sequencing and analysis of the T. urartu genome, a donor of polyploid wheat A subgenome, was led by the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences. In this review, we summarize the research progress on structure and evolution analyses of the T. urartu genome to provide some valuable information for promoting the basic and applied researches of wheat.


Subject(s)
Genome, Plant , Triticum/genetics , Aegilops/genetics , Chromosome Mapping , Polyploidy , Triticum/classification
10.
Cancer Chemother Pharmacol ; 83(1): 179-189, 2019 01.
Article in English | MEDLINE | ID: mdl-30406839

ABSTRACT

OBJECTIVE: To investigate the potential inhibitory effects of structurally novel steroidal dimer by001 in esophageal cancer in vitro. METHODS: The cytotoxicity of by001 on esophageal, gastric, neuroblastoma and prostate cancer cells was examined MTT assay and colony formation assay. By001 induced apoptosis and production of intracellular reactive oxygen species on esophageal cancer cells Ec109, TE-1 and human normal gastric epithelial cells GES-1 was detected by flow cytometry. The effect of by001 on mitochondrial membrane potential was detected by fluorescence microscope through JC-1 staining. The level of intracellular reactive oxygen species was measured by fluorescence microscope and flow cytometry via DCFH-DA staining. The effect of by001 on members of Bcl-2 family, Fas, LC3, PARP and caspases was determined by Western blot. The effect of by001 on migration was measured by transwell assay. RESULTS: By001 effectively inhibited proliferation of esophageal, gastric, neuroblastoma and prostate cancer cells in a time- and concentration-dependent manner in vitro. By001 reduced the number and the size of colonies at low micromolar concentrations, elevated cellular ROS levels and caused mitochondrial dysfunction in esophageal cancer cells. Molecular mechanistic studies showed that by001 triggered apoptosis through regulating members of Bcl-2 family and Fas. CONCLUSIONS: These findings suggested that by001 may inhibited proliferation of esophageal cancer cells through mitochondria and death receptor-mediated apoptotic pathways, autophagy induction, as well as suppressed migration of esophageal cancer cells.


Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Movement/drug effects , Cell Proliferation/drug effects , Esophageal Neoplasms/drug therapy , Polycyclic Compounds/chemistry , Polycyclic Compounds/pharmacology , Steroids/chemistry , Apoptosis , Esophageal Neoplasms/pathology , Humans , Membrane Potential, Mitochondrial , Mitochondria/drug effects , Mitochondria/metabolism , Molecular Structure , Reactive Oxygen Species/metabolism , Structure-Activity Relationship , Tumor Cells, Cultured
11.
Eur J Med Chem ; 145: 11-22, 2018 Feb 10.
Article in English | MEDLINE | ID: mdl-29310026

ABSTRACT

A series of new steroidal pyridines have been synthesized through the based-promoted three-component reaction and preliminarily evaluated for their antiproliferative activity against different types of cancer cell lines. SARs studies showed that the heterocyclic rings attached to the 4-position of the pyridine ring were preferred over the phenyl rings for the activity. Among these compounds, the most potent compound exhibited good growth inhibition against all the tested cancer cells, especially for PC-3 cells with an IC50 value of 1.55 µM. Further mechanistic studies revealed that the most potent compound inhibited colony formation, migration and evasion of PC-3 cells in a concentration-dependent manner as well as induced apoptosis of PC-3 cells possibly through the mitochondria-related apoptotic pathways. Caspase-3/-9 and PARP were activated, finally leading to the apoptosis of PC-3 cells. For the androgen-sensitive (AR+) prostate cancer cell line LNCaP, the most potent compound was less potent than abiraterone with the IC50 value of 8.48 and 3.29 µM, respectively. The most potent compound could be used as a starting point for the development of new steroidal heterocycles with improved anticancer potency and selectivity. The synthesized steroidal pyridines contain the functional -OEt and CN groups, which could be used for further modifications for the construction of the steroid library.


Subject(s)
Antineoplastic Agents/pharmacology , Pyridines/pharmacology , Steroids/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Movement/drug effects , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Pyridines/chemical synthesis , Pyridines/chemistry , Steroids/chemical synthesis , Steroids/chemistry , Structure-Activity Relationship , Tumor Cells, Cultured
12.
Oncol Lett ; 13(3): 1101-1108, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28454220

ABSTRACT

Hypoxia occurs in a wide range of solid tumors, and is strongly associated with radio-resistance of malignant tumors. The aim of the present study was to investigate the effect of endostatin combined with ionizing radiation (IR) on hypoxic conditions. A total of 24 mice bearing SKOV3 ovarian carcinoma were divided into three groups. Following injection with pEgr-1-endostatin plasmid for 12 h, the mice in the endostatin-IR-treated group were exposed to 300 cGy/min X-ray for 48 h, and the IR-treated group was exposed to the same condition. Then, the expression of endostatin, hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) was detected by reverse transcription-polymerase chain reaction, ELISA, immunohistochemistry and western blotting. In addition, the tumor microvessel density (MVD) was examined by immunohistochemistry analysis of cluster of differentiation 31-positive cells. The results revealed that pEgr-1-endostatin was successfully induced by IR. The level of endostatin messenger RNA in the endostatin-IR-treated group was significantly higher than that in the control and IR-treated groups (F=380.078, P<0.001). Statistical differences were also examined at the protein level by western blotting and ELISA. An obvious increase in MVD was observed in the IR-treated group compared with that in the control group (t=7.040, P<0.001), and a significant decrease in MVD was observed in the endostatin-IR-treated group compared with that in the control group (t=18.153, P<0.001). By comparing the morphology of the tumor vasculature in the three groups, it was noticed that the microvessels in the endostatin-IR-treated group were more regularly distributed and had fewer giant branches than those in the IR-treated group. Further investigation revealed that the expression levels of HIF-1α and VEGF in the endostatin-IR-treated group were lower compared with those in the control (t=5.339, P=0.001; and t=13.880, P<0.001, respectively) and the IR-treated groups (t=12.930, P<0.001; and t=14.050, P<0.001, respectively). Our findings suggested that endostatin decreased the number of microvessels via the HIF-1/VEGF signaling pathway, and that pEgr-1-endostatin combined with IR may improve hypoxic conditions and may be a novel approach for treating solid tumors.

13.
Oncotarget ; 7(45): 72990-73002, 2016 Nov 08.
Article in English | MEDLINE | ID: mdl-27659528

ABSTRACT

Paclitaxel, a taxane, is a cytotoxic chemotherapeutic agent that targets microtubules. It has become a front-line therapy for a broad range of malignancies, including lung, breast, gastric, esophageal, and bladder carcinomas. Although paclitaxel can inhibit tumor development and improve survival, poor solubility, myelotoxicity, allergic reactions, and drug resistance have restricted its clinical application. Paclitaxel is frequently combined with other chemotherapeutics to enhance the antitumor effects and reduce side effects. We synthesized geridonin, a derivative of oridonin, and demonstrate that geridonin and paclitaxel act synergistically to inhibit the growth of gastric cancer cells. Importantly, geridonin enhanced the antitumor effects of paclitaxel without increasing toxicity in vivo. Mechanistic analysis revealed that administration of geridonin in combination with paclitaxel up-regulated the tumor suppressor PTEN and inhibited phosphorylation of Akt and MDM2. This led to the accumulation of p53 and induced apoptosis though the mitochondrial pathway. Thus, geridonin in combination with paclitaxel is a new treatment strategy for gastric cancer.


Subject(s)
Antineoplastic Agents/pharmacology , Diterpenes, Kaurane/pharmacology , Paclitaxel/pharmacology , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Animals , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Disease Models, Animal , Drug Synergism , Humans , Male , Membrane Potential, Mitochondrial/drug effects , Mice , PTEN Phosphohydrolase , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology , Xenograft Model Antitumor Assays
14.
Steroids ; 115: 147-153, 2016 11.
Article in English | MEDLINE | ID: mdl-27639101

ABSTRACT

The synthesis of novel steroidal 3-cyano-2-aminopyridines using enaminonitrile and various primary amines was established under solvent-free condition. Structures of the new compounds were characterized by MS, 1H and 13C NMR data and the structure of 2-aminopyridine of the product 5b was further confirmed by X-ray analysis. The reaction mechanism was proposed on the basis of the key intermediate obtained. The adjacent amine and nitrile groups existed in the final products have the potential for late stage functionalization, which would provide efficient access to steroidal compound collections with structural diversity and complexity.


Subject(s)
Aminopyridines/chemistry , Aminopyridines/chemical synthesis , Solvents/chemistry , Steroids/chemistry , Steroids/chemical synthesis , Crystallography, X-Ray , Heterocyclic Compounds, 2-Ring/chemical synthesis , Heterocyclic Compounds, 2-Ring/chemistry , Molecular Structure , Nitriles/chemical synthesis , Nitriles/chemistry
15.
Zhongguo Zhong Yao Za Zhi ; 39(13): 2489-94, 2014 Jul.
Article in Chinese | MEDLINE | ID: mdl-25276969

ABSTRACT

OBJECTIVE: To evaluate in vivo pharmacokinetics of Ophiopogonis Radix polysaccharide MDG-1 oily suspension injection prepared with different prescriptions in rats, and explore the feasibility of the long-acting drug delivery of MDG-1 Injection by using the oily suspension drug release system. METHOD: MDG-1 microparticles were prepared by the anti-solvent precipitation method. Their size and size distribution were characterized. Castor oil with a high viscosity or aluminum stearate were added into soybean oil with a low viscosity, in order to prepare oily media with different viscosities, detect their rheological properties and screen out superior prescriptions for in vivo evaluation. RESULT: The average size of microparticles was 21.81 microm, and the span between them was 2.63. The in vivo evaluation was conducted for prescriptions of mixed oil (soybean oil/castor oil, 2: 3) and soybean oils gelled by 2% and 4% aluminium stearate. Among them, the prescription of soybean gelled by 4% aluminium stearate could significantly reduce C(max) and prolong the apparent t1/2, with the MDG-1 release time of several days. CONCLUSION: It is feasible to achieve the long-acting MDG-1 drug delivery by using oily media with a high viscosity.


Subject(s)
Chemistry, Pharmaceutical/methods , Drugs, Chinese Herbal/pharmacokinetics , Ophiopogon/chemistry , Plant Oils/chemistry , Polysaccharides/pharmacokinetics , Animals , Drug Delivery Systems , Drugs, Chinese Herbal/administration & dosage , Drugs, Chinese Herbal/chemistry , Male , Polysaccharides/administration & dosage , Polysaccharides/chemistry , Rats , Rats, Sprague-Dawley , Viscosity
16.
Huan Jing Ke Xue ; 34(9): 3416-22, 2013 Sep.
Article in Chinese | MEDLINE | ID: mdl-24288984

ABSTRACT

The genetic diversity of picoeukaryotic phytoplankton in the 30 lakes along the middle-lower reaches of the Yangtze River was studied using flow cytometry combined with terminal restriction fragment length polymorphism (T-RFLP). The objectives of this study were to confirm the variance in the genetic diversity of picoeukaryotic phytoplankton among the lakes and to reveal its main affecting factors. Though the lakes investigated tended to or already were eutrophic, T-RFLP profiles of 18S rRNA gene fragments from picoeukaryotic phytoplankton showed high diversity. There were altogether 197 T-RFs detected from the lakes that we investigated, with 89 of them obtained in less than 3 lakes. Cluster analysis indicated their similarity was lower than 80%. Shannon-wiener diversity index showed that mesotrophic lakes contained more diverse picoeukaryotic phytoplankton community than eutrophic lakes. The canonical correspondence analysis revealed that the concentration of the total nitrogen had the most important impact on the picoeukaryotic phytoplankton communities (P =0. 006). The results showed that the genetic diversity of picoeukaryotic phytoplankton in the lakes were of great environmental heterogeneity and closely related to the trophic status. Two CCA axes can only explain 10.0% of the total variance in picoeukaryotic phytoplankton composition, suggesting that the evolution of picoeukaryotic phytoplankton was probably connected to the top-down manipulation as well.


Subject(s)
Genetic Variation , Lakes/microbiology , Phytoplankton/classification , Rivers/microbiology , China , Phytoplankton/genetics , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 18S/genetics
17.
Huan Jing Ke Xue ; 34(6): 2126-33, 2013 Jun.
Article in Chinese | MEDLINE | ID: mdl-23947023

ABSTRACT

To disclose the impact of different CO2 concentrations (270 x 10(-6), 380 x 10(-6), 750 x 10(-6)) on physiological features of spring phytoplankton, an in situ simulated experiment was carried out in Meiliang Bay of Taihu Lake from 29 April to 26 May in 2012. The results showed that atmospheric CO2 elevation would significantly alter the pH value and carbonate chemical environments of Taihu Lake, resulting in weakening the advantages of carbon concentrating mechanism (CCM) of phytoplankton. Phytoplankton in Taihu Lake tended to use more dissolved CO2 (CO2, aq) due to the deliberate CO2 sequestration under the high CO2 level treatment. When atmospheric CO2 concentration doubles at the end of century, the maximum growth rate constant of phytoplankton (U(max)), NPP, chlorophyll a (Chl-a)-specific NPP would increase by 63.1%, 69.6% and 33.8%, respectively. Atmospheric CO2 elevation promoted the maximum photosynthetic efficiency of chlorophyta and bacillariophyta in Taihu Lake and its promotion effect on bacillariophyta was more notable than that on chlorophyta. However, it did not change the photosynthetic efficiency of cyanobacteria which was very low in spring. Meanwhile, the stoichiometry value of phytoplankton changed significantly due to the CO2 elevation, as phytoplankton cells assimilated more C and N, but less P under the treatment of high CO2 level. Our results indicated the enhanced CO2 level could dramatically change the physiological features of phytoplankton. This information would help us to understand and predict the response of phytoplankton in Taihu Lake to the future climate change.


Subject(s)
Atmosphere/analysis , Carbon Dioxide/analysis , Lakes , Phytoplankton/physiology , Carbonates/analysis , China , Chlorophyta/growth & development , Computer Simulation , Diatoms/growth & development , Ecosystem , Fresh Water/chemistry , Phytoplankton/growth & development , Seasons
18.
Huan Jing Ke Xue ; 34(4): 1485-91, 2013 Apr.
Article in Chinese | MEDLINE | ID: mdl-23798133

ABSTRACT

A novel approach based on flow cytometric sorting followed by construction of 18S rRNA clone libraries was used to study the diversity of eukaryotic picophytoplankton of lakes. The composition of eukaryotic picophytoplankton community appeared highly variable in three lakes. Eukaryotic picophytoplankton was dominated by Cryptophyta in the Lake Xuanwu, and was mainly composed of Cryptophyta and Chrysophyta in the Lake Zixia. In the Lake Taihu, four phyla were discovered, including Cryptophyta, Chrysophyta, Bacillariophyta and Chlorophyta. Meanwhile, the diversity of eukaryotic picophytoplankton differed in various lake regions. In the Meiliang Bay, Chrysophyta was the dominant, and the other three phyla were found in the Gonghu Bay. In the central lake, all of those four phyla were discovered, implying this region contained the highest diversity. The canonical correspondence analysis between the diversity of eukaryotic picophytoplankton and environmental factors revealed the concentration of total phosphorus had the highest important impact on the eukaryotic picophytoplankton communities.


Subject(s)
Genetic Variation , Phytoplankton/classification , Phytoplankton/genetics , China , Chlorophyta/genetics , Chlorophyta/growth & development , Cryptophyta/genetics , Cryptophyta/growth & development , Diatoms/genetics , Diatoms/growth & development , Environmental Monitoring , Eutrophication , Flow Cytometry/methods , Fresh Water , Lakes , Phytoplankton/growth & development
20.
Mar Biotechnol (NY) ; 14(2): 245-51, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21997848

ABSTRACT

Sulfide is a natural, widely distributed, poisonous substance, and sulfide:quinone oxidoreductase (SQR) is responsible for the initial oxidation of sulfide in mitochondria. In this study, we examined the response of SQR to sulfide exposure (25, 50, and 150 µM) at mRNA, protein, and enzyme activity levels in the body wall and hindgut of the echiuran worm Urechis unicinctus, a benthic organism living in marine sediments. The results revealed SQR mRNA expression during sulfide exposure in the body wall and hindgut increased in a time- and concentration-dependent manner that increased significantly at 12 h and continuously increased with time. At the protein level, SQR expression in the two tissues showed a time-dependent relationship that increased significantly at 12 h in 50 µM sulfide and 6 h in 150 µM, and then continued to increase with time while no significant increase appeared after 25 µM sulfide exposure. SQR enzyme activity in both tissues increased significantly in a time-dependent manner after 50 µM sulfide exposure. We concluded that SQR expression could be induced by sulfide exposure and that the two tissues studied have dissimilar sulfide metabolic patterns. A U. unicinctus sulfide-induced detoxification mechanism was also discussed.


Subject(s)
Annelida/enzymology , Gene Expression Regulation, Enzymologic/drug effects , Models, Molecular , Quinone Reductases/metabolism , Sulfides/toxicity , Animals , DNA Primers/genetics , Dose-Response Relationship, Drug , Quinone Reductases/genetics , Real-Time Polymerase Chain Reaction , Time Factors
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