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1.
Med Sci Monit ; 27: e927464, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33500378

RESUMO

BACKGROUND Natural killer (NK) cells are important for the prognosis of multiple cancers, but their prognostic value remains to be evaluated in patients with gastric cancer. Thus, this retrospective study was conducted at a single center to investigate the association between percentage of NK cells in the peripheral blood and prognosis in patients with gastric cancer. MATERIAL AND METHODS The data of 180 gastric cancer patients were collected. Univariate and multivariate Cox regression models were applied to screen candidate prognostic factors. A time-dependent receiver operating characteristic curve was employed to evaluate the ability of NK cells as a prognostic marker. Furthermore, we determined the correlation between the NK cells percentage and other parameters and their clinical significance. RESULTS Patients with a higher percentage of NK cells survived longer than those with a lower percentage of NK cells. Cox analysis revealed that NK cells could be used as an independent indicator for patients with gastric cancer. The percentage of NK cells was positively correlated with lymphocyte count and albumin, but was negatively correlated with CA125 and neutrophil-lymphocyte ratio. The area under the curve for NK cells in predicting the 5-year survival rate for gastric cancer was 0.792. This increased to 0.830 upon combining NK cells with neutrophil-lymphocyte ratio. Patients at early T, N, and clinical stages possessed a significantly higher percentage of NK cells compared to those at advanced T, N, and clinical stages of gastric cancer. CONCLUSIONS Our results suggest that a higher percentage of NK cells predicts is associated with longer survival of gastric cancer patients and could serve as an independent prognostic biomarker.


Assuntos
Células Matadoras Naturais/imunologia , Neoplasias Gástricas/sangue , Adulto , Idoso , Biomarcadores Tumorais/sangue , Antígeno Ca-125/sangue , Antígeno Ca-125/imunologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Células Matadoras Naturais/patologia , Contagem de Linfócitos , Linfócitos/imunologia , Masculino , Proteínas de Membrana/sangue , Proteínas de Membrana/imunologia , Pessoa de Meia-Idade , Neutrófilos/imunologia , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Estudos Retrospectivos , Albumina Sérica/imunologia , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/patologia , Taxa de Sobrevida
2.
Front Mol Biosci ; 8: 733271, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765644

RESUMO

Background: The role of hyaluronan-mediated motility receptor (HMMR) in colorectal cancer (CRC) remains unclear. The present study aimed to explore the association of HMMR with the development and prognosis of CRC using sequence datasets, clinical tissues, blood samples, and cell lines. Methods: CRC datasets were downloaded from TCGA and GEO databases. Forty CRC tissue samples, 120 CRC blood samples, and 100 healthy controls were collected. Four CRC cell lines (HCT116, HT-29, LoVo, and SW480) and one normal human colon mucosal epithelial cell line (NCM460) were cultured. RT-qPCR was used to determine the expression of HMMR in the tissues and cell lines. ELISA was used to measure HMMR levels in the blood samples. Results: The expression of HMMR was significantly increased in CRC tissues than in corresponding adjacent tissues based on TCGA and GEO datasets, and clinical CRC tissues. No associations were found between the expression of HMMR and the TNM stage or other clinical parameters. The expression of HMMR varied in different CRC cell lines. The blood levels of HMMR tended to be higher in patients with CRC than in healthy controls. TCGA and GEO datasets showed inconsistent results regarding the association of HMMR expression with the survival of patients with CRC. Conclusion: The expression of HMMR is increased in CRC tissues but not in the blood. The expression of HMMR is independent of CRC development and has no prognostic significance in patients with CRC.

3.
Ann Surg Treat Res ; 100(6): 338-346, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34136430

RESUMO

PURPOSE: This study was aimed to evaluate the clinical significance and prognostic value of CRP/albumin ratio (CAR) in patients with gastric cancer. METHODS: The data of 205 gastric cancer patients who underwent surgery was analyzed retrospectively. The association of CAR with the clinical features and prognostic value in gastric cancer was analyzed. The data of this study was combined with previous studies to further determine the prognostic value of CAR in patients with gastric cancer using a meta-analysis method. RESULTS: Cox analysis revealed that preoperative CAR was an independent prognosis indicator in patients with gastric cancer. High expression of CAR indicated a shorter survival time than in those with lower expression. CAR has a higher prognostic value in the 1-, 3-, and 5-year overall survival in patients with gastric cancer. CAR showed significant difference regarding the gastric cancer patients' age, M stage, and clinical stage. The discriminate value of CAR in M stage of gastric cancer was high (area under the curve, 0.809). A meta-analysis combining previous data and our data showed that preoperative CAR demonstrated a significant association with the overall survival of patients with gastric cancer. CONCLUSION: This study demonstrated that preoperative CAR could serve as an important prognostic indicator in patients with gastric cancer.

4.
Front Oncol ; 11: 741612, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956868

RESUMO

BACKGROUND: The role of 18F-flurodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET/CT) in colorectal cancer (CRC) remains unclear. This study aimed to explore the association of the maximum standardized uptake value (SUVmax), a parameter of 18F-FDG PET/CT, with KRAS mutation, the Ki-67 index, and survival in patients with CRC. METHODS: Data of 66 patients with CRC who underwent 18F-FDG PET/CT was retrospectively collected in our center. The clinical significance of the SUVmax in CRC and the association of the SUVmax with KRAS mutation and the Ki-67 index were determined. A meta-analysis was conducted by a systematic search of PubMed, Web of Science, and CNKI databases, and the data from published articles were combined with that of our study. The association of the SUVmax with KRAS mutation and the Ki-67 index was determined using the odds ratio to estimate the pooled results. The hazard ratio was used to quantitatively evaluate the prognosis of the SUVmax in CRC. RESULTS: By analyzing the data of 66 patients with CRC, the SUVmax was found not to be related to the tumor-node-metastasis stage, clinical stage, sex, and KRAS mutation but was related to the tumor location and nerve invasion. The SUVmax had no significant correlation with the tumor biomarkers and the Ki-67 index. Data of 17 studies indicated that the SUVmax was significantly increased in the mutated type compared with the wild type of KRAS in CRC; four studies showed that there was no remarkable difference between patients with a high and low Ki-67 index score regarding the SUVmax. Twelve studies revealed that the SUVmax had no significant association with overall survival and disease-free survival in CRC patients. CONCLUSIONS: Based on the combined data, this study demonstrated that the SUVmax of 18F-FDG PET/CT was different between colon and rectal cancers and associated with KRAS mutation but not the Ki-67 index; there was no significant association between the SUVmax and survival of patients with CRC.

5.
Int Immunopharmacol ; 90: 107145, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33162344

RESUMO

BACKGROUND: The role of plasma heat shock protein 90alpha (Hsp90α) in gastric cancers remains unclear. This study aimed to clarify the diagnostic and prognostic value of plasma Hsp90α in gastric cancer. METHODS: Data regarding 976 gastric cancer, 50 gastric inflammatory diseases, and 100 healthy controls were collected. Plasma Hsp90α levels in gastric cancer were compared to those in controls. Its correlation with tumor biomarkers and immune cells was examined. The association of plasma Hsp90α with clinical features and the diagnostic and prognostic value in gastric cancer were also determined. RESULTS: Plasma Hsp90α levels were remarkably increased in gastric cancer, compared to those in gastric inflammatory diseases and healthy controls. Moreover, plasma Hsp90α was correlated with CEA, CA125, CA153, CA199, T cells, Th/Ts ratio, and B cells. Plasma Hsp90α was also associated with the metastasis stage. Multivariate logistic regression analysis revealed that Hsp90α, B cells, and T cells were significantly associated with gastric cancer. Plasma Hsp90α has a moderate diagnostic value, which increased when combined with B cell, T cells. Finally, plasma Hsp90α was not associated with the survival of gastric cancer patients. CONCLUSION: Plasma Hsp90α was elevated in gastric cancer and correlated with tumor biomarkers and immune cells. Plasma Hsp90α was associated with the metastasis stage and had moderate diagnostic performance but little prognostic value in gastric cancer.


Assuntos
Biomarcadores Tumorais/sangue , Proteínas de Choque Térmico HSP90/sangue , Neoplasias Gástricas/diagnóstico , Adulto , Idoso , Linfócitos B/imunologia , Feminino , Humanos , Linfócitos do Interstício Tumoral/imunologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Estudos Retrospectivos , Neoplasias Gástricas/sangue , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/patologia , Linfócitos T/imunologia , Regulação para Cima
6.
J Environ Qual ; 37(2): 712-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18396559

RESUMO

A near-trench paddy field experiment with five urea application rates (0-360 kg N ha(-1) in 90-kg increments) was conducted on a paddy soil in the Taihu Lake Region of China to elucidate N losses through lateral seepage during three rice (Oryza sativa L.) growing seasons. The total N (Nt), NH4(+) -N, and NO3(-) -N concentrations in the lateral seepage water increased with increasing N rates. The seasonal Nt fluxes by lateral seepage varied from 6.8 to 25.6 kg N ha(-1) for urea application rates of 90 to 360 kg N ha(-1). Lateral seepage accounted for 4.7 to 6.6% of the Nt applied, implying that lateral seepage was an important pathway of N loss from near-trench paddy fields. The cumulative N loss via lateral seepage was significantly related to N fertilization rate (P = 0.05). Floodwater level was also identified as a main factor affecting N losses via lateral seepage from paddy fields, as indicated by a positive linear relationship (R2 = 0.43) between floodwater level and daily lateral flow during the flooded period (P = 0.05). Under the conditions of these experiments, a shallow floodwater depth of 50 mm, urea application rates of 90 kg N ha(-1) or less, and no rainfall within 1 wk after N application reduced N losses by lateral seepage from paddy fields.


Assuntos
Fertilizantes , Nitrogênio/análise , Oryza , Compostos de Amônio Quaternário/análise , Ureia , Poluentes Químicos da Água/análise , Agricultura/métodos , China , Monitoramento Ambiental , Nitratos/análise , Chuva
7.
Zhonghua Fu Chan Ke Za Zhi ; 43(11): 843-8, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19087569

RESUMO

OBJECTIVE: To explore the relationship between hormone therapy (HT) in women with ovarian malignancy and prognosis. METHODS: HT was used in 31 patients with ovarian cancer after surgery, and 44 cases with ovarian cancer served as control. The expression of estrogen receptor (ER)alpha, ERbeta and progesterone receptor (PR) was detected by immunohistochemical staining respectively. The level of serum calcitonin and transforming growth factor alpha (TGFalpha) was detected by radio-immune and enzyme-linked immunosorbent assay pre- or post-surgery, as well as half a year to one year later post-surgery respectively in these cases. The survival curve of Kaplan-Meier and log-rank test as well as scale risk of Cox model were used to analyze the relationship between HT and prognosis of ovarian cancer. RESULTS: (1) The results of log-rank test showed that there was no difference in survival curve of patients with or without HT [(1108 +/- 52), (1086 +/- 43) d; P = 0.940]; the results of scale risk of Cox model also showed that HT was not an independent prognosis factor for patients with HT. (2) There was no relationship with HT and the accumulated survival in patients with either positive or negative expression of ERalpha, ERbeta and PR in tissue; as well as between HT and the level of serum TGFalpha pre-, post-surgery, or half a year to one year after surgery. (3) The level of serum calcitonin in patients without HT post-surgery half a year to one year later was higher than that pre-surgery [(141 +/- 13), (95 +/- 11) microg/L; P < 0.05], but there was no significant difference between patients with HT half a year to one year later post-surgery and pre-surgery [(90 +/- 18) microg/L, (93 +/- 14) microg/L; P > 0.05]. (4) There was a significant difference in body and emotion function between HT and without HT groups [(1.84 +/- 1.50), (1.45 +/- 0.82); (12.69 +/- 10.20), (12.90 +/- 11.61); P < 0.05], as well as in sex quality and autonomic nerve maladjustment and in the special list made [(1.05 +/- 0.74), (1.77 +/- 1.08); (10.10 +/- 3.21), (13.09 +/- 4.30); P < 0.05]. CONCLUSIONS: There is no adverse influence on prognosis in using of HT for patients with ovarian cancer after surgery. HT for patients with ovarian cancer post-surgery can help keep a stable level of serum calcitonin as well as improve the quality of life.


Assuntos
Terapia de Reposição de Estrogênios , Estrogênios/uso terapêutico , Medroxiprogesterona/uso terapêutico , Neoplasias Ovarianas/patologia , Qualidade de Vida , Adulto , Calcitonina/sangue , Cistadenocarcinoma Seroso/mortalidade , Cistadenocarcinoma Seroso/patologia , Cistadenocarcinoma Seroso/cirurgia , Quimioterapia Combinada , Ensaio de Imunoadsorção Enzimática , Estrogênios/administração & dosagem , Feminino , Humanos , Imuno-Histoquímica , Medroxiprogesterona/administração & dosagem , Pessoa de Meia-Idade , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/cirurgia , Pós-Menopausa , Prognóstico , Quinestrol/administração & dosagem , Quinestrol/uso terapêutico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Inquéritos e Questionários , Análise de Sobrevida , Fator de Crescimento Transformador alfa/sangue , Adulto Jovem
8.
J Environ Sci (China) ; 19(12): 1474-81, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18277652

RESUMO

A field experiment located in Taihu Lake Basin of China was conducted, by application of urea or a mixture of urea with manure, to elucidate the interception of nitrogen (N) export in a typical rice field through "zero-drainage water management" combined with sound irrigation, rainfall forecasting and field drying. N concentrations in floodwater rapidly declined before the first event of field drying after three split fertilizations, and subsequently tended to return to the background level. Before the first field drying, total particulate nitrogen (TPN) was the predominant N form in floodwater of plots with no N input, dissolved inorganic nitrogen (DIN) on plots that received urea only, and dissolved organic nitrogen (DON) on plots treated with the mixture of urea and manure. Thereafter TPN became the major form. No N export was found from the rice field, but total nitrogen (TN) of 15.8 kg/hm2 was remained, mainly due to soil N sorption. The results recommended the zero-drainage water management for full-scale areas for minimizing N export.


Assuntos
Agricultura/métodos , Fertilizantes/análise , Nitrogênio/análise , Oryza , Poluentes Químicos da Água/análise , China , Esterco , Fósforo , Potássio , Movimentos da Água
9.
Mol Med Rep ; 14(2): 1117-22, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27314447

RESUMO

The present study aimed to investigate the chemopreventive effect of Camellia nitidissima flowers water extract (CNFE) on the Eca109 human esophageal squamous cell carcinoma (ESCC) cell line. The antiproliferative effect on Eca109 cells was determined using the trypan blue exclusion assay. The effects of CNFE on apoptosis and cell cycle arrest were investigated by flow cytometry. CNFE inhibited cell growth in both a dose­ and time­dependent manner in Eca109 cells. CNFE also caused dose­ and time­dependent apoptosis of these cells. Treatment of cells with CNFE resulted in dose­dependent G0/G1 phase arrest of the cell cycle. The data demonstrated that CNFE serves antiproliferative effects against human ESCC Eca109 cells by inducing apoptosis and interrupting the cell cycle. These results suggested that CNFE has the potential to be a chemoprotective agent for ESCC.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Camellia/química , Ciclo Celular/efeitos dos fármacos , Flores/química , Extratos Vegetais/farmacologia , Carcinoma de Células Escamosas , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos
10.
Oncotarget ; 7(47): 77558-77564, 2016 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-27813499

RESUMO

We investigated the levels of target lymphocyte subsets in peripheral blood lymphocyte samples from patients with hepatocellular carcinoma (HCC). A total of 715 high-risk patients with primary HCC were recruited in Guangxi, China as the case group. The control group included 100 patients who received health examinations at the same hospital during the same period. Fasting elbow venous blood (10 mL) was collected from each participant, and flow cytometry was used to detect the levels of NK cells and CD3+, CD4+ and CD19+ T cells in peripheral blood samples. All included patients with prmary HCC were treated by surgical resection, and followed up for one year. The levels of CD19+ and NK cells were lower in cases than in controls (both P < 0.05). In addition, the level of CD8+ cells was greater in the case group than in the control group (P < 0.05). In the high-HCC-risk population, CD8+, CD19+ and NK cell levels all differed between male and female patients, patients in TNM stages I-II and stages III-IV, patients with and without extrahepatic metastasis, and patients with and without HBV infection (all P < 0.05). After follow-up, detected recurrence and survival rate was 33.71% and 83.64%, respectively. CD8+ levels was reduced following surgical resection, whereas the levels of CD19+ and NK cells were increased (all P < 0.05). In conclusion, altered levels of CD8+, CD19+ and NK cell levels may be used as reference values for monitoring immune function in certain populations with high HCC risk, and as potential evidence for the clinical diagnosis and treatment of HCC.


Assuntos
Carcinoma Hepatocelular/sangue , Neoplasias Hepáticas/sangue , Contagem de Linfócitos , Subpopulações de Linfócitos , Adulto , Antígenos CD/metabolismo , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidade , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Subpopulações de Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico
11.
Ying Yong Sheng Tai Xue Bao ; 26(4): 1271-8, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-26259473

RESUMO

Colloids play a key role in the transference process of phosphorus (P) in soil. Activation and transference of soil colloidal phosphorus have great effect on soil P pool and the surrounding water quality. This paper summarized the current studies on soil colloidal P, discussing the effects of the various factors (e. g., soil physical and chemical properties, fertilization, rainfall and soil amendments) on the transference of soil colloidal P. Some advanced analysis technologies (e.g., flow field-flow fractionation, transmission electron microscope-energy dispersive X-ray spectrometer, X-ray absorption near-edge structure and nuclear magnetic resonance) and methods of reducing soil colloidal P were also involved. This review would provide important information on the mechanism of soil colloidal P transference.


Assuntos
Fósforo/análise , Solo/química , Coloides , Poluentes do Solo/análise , Qualidade da Água
12.
Huan Jing Ke Xue ; 35(9): 3381-8, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25518655

RESUMO

Wetlands litter decomposition affects wetlands nutrient cycling. The decomposition progress of standing litter was monitored and the litterbag simulation experiment was carried out in order to analyze dynamics of litter decomposition and phosphorus release in Phragmites australis (PA), Spartina alterniflora (SA) and Scirpus mariqueter (SM) marshes of Hangzhou Bay coastal wetland. Results show that the dry mass of standing litter and P concentration decrease gradually and the litter drops to the sediment surface after 180 d. There are distinctive stages of the plant litter decomposition in litterbag simulation experiments. The loss rate is faster during 0- 15 d than that of later days. The loss rate in root decomposition of three plants are SM > PA > SA, while the trend is opposite for that of aboveground tissues. The time needed for 95% of dry mass decomposition in the plant tissues is between 1. 2- 8. 3 a. The P concentration in litters decreases rapidly in the initial stage and then increases slowly while the net P pools decreases all the time. Pearson's correlation coefficient shows that there is no significant correlation between the litter decomposition rate and C/N ratio. However, the litter C/P ratio affects greatly on plant decomposition rate. Environmental factors in the atmospheric temperature also have an impact on the decomposition rate of leaves. The different decomposition progresses between standing litter and litterbag are caused by environmental factors.


Assuntos
Fósforo/química , Folhas de Planta , Áreas Alagadas , Baías , China , Monitoramento Ambiental , Sedimentos Geológicos/química , Poaceae
13.
J Zhejiang Univ Sci B ; 13(4): 274-82, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22467369

RESUMO

Field experiments provide an opportunity to study the effects of fertilization on soil organic carbon (SOC) sequestration. We sampled soils from a long-term (25 years) paddy experiment in subtropical China. The experiment included eight treatments: (1) check, (2) PK, (3) NP, (4) NK, (5) NPK, (6) 7F:3M (N, P, K inorganic fertilizers+30% organic N), (7) 5F:5M (N, P, K inorganic fertilizers+50% organic N), (8) 3F:7M (N, P, K inorganic fertilizers+70% organic N). Fertilization increased SOC content in the plow layers compared to the non-fertilized check treatment. The SOC density in the top 100 cm of soil ranged from 73.12 to 91.36 Mg/ha. The SOC densities of all fertilizer treatments were greater than that of the check. Those treatments that combined inorganic fertilizers and organic amendments had greater SOC densities than those receiving only inorganic fertilizers. The SOC density was closely correlated to the sum of the soil carbon converted from organic amendments and rice residues. Carbon sequestration in paddy soils could be achieved by balanced and combined fertilization. Fertilization combining both inorganic fertilizers and organic amendments is an effective sustainable practice to sequestrate SOC.


Assuntos
Carbono/análise , Carbono/química , Fertilizantes , Compostos Orgânicos/química , Oryza/química , Solo/química
14.
Ying Yong Sheng Tai Xue Bao ; 22(10): 2757-64, 2011 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-22263485

RESUMO

Solid state phosphorous is an important phosphorus speciation controlling the phosphorous bioavailability and mobility in the environment. Synchrotron-based X-ray absorption near-edge structure (XANES) spectroscopy, with its unique advantage of being a non-destructive method in identifying the local chemical information of target element at molecular level in situ, has become one of the frontier technologies for characterizing the speciation of chemical substances and clarifying the microscopic mechanisms of chemical reactions, attracting extensive attention in the field of environmental chemistry. This paper briefly introduced the basic theory of phosphorus XANES spectroscopy, summarized the applications of XANES spectroscopy in the researches of solid state phosphorus speciation in minerals, soils, and organic fertilizers, and analyzed the challenges and prospects of the applications of XANES spectroscopy in identifying the solid state phosphorus speciation in the environmental samples. It was pointed out that XANES spectroscopy should combine with other microscopic spectroscopic techniques and macroscopic analytical methods, complementing each other, to provide a comprehensive and effective technical support for the research of the speciation characterization and transformation mechanisms of phosphorus in the environment.


Assuntos
Fósforo/química , Poluentes do Solo/análise , Espectroscopia por Absorção de Raios X/métodos , Fósforo/análise , Compostos de Fósforo/análise , Compostos de Fósforo/química , Solo/análise , Solo/química , Síncrotrons , Espectroscopia por Absorção de Raios X/instrumentação
15.
Huan Jing Ke Xue ; 31(4): 924-30, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20527172

RESUMO

Seasonal variations of self-purification ability for small natural shallow lakes in South Lake Taihu were investigated. The results showed that seasonal difference of self-purification of permanganate index, total nitrogen (TN), ammonium (NH4(+)-N), nitrate (NO3(-)-N), total phosphorus (TP), chlorophyll (Chl-a) in small shallow lakes were remarkable. Effects of self-purification were better in spring and winter, and were worse in summer by NH4(+)-N and NO3(-)-N and in autumn by TP and Chl-a. Organic pollution was light, TN and TP pollution were seriously in four seasons. Concentrations of TN and TP brought a well condition to algae growth, and lakes were eutrification easily by the limiting factor of phosphorus. Concentrations of Chl-a were showed that lakes were eutrophic in summer or autumn and mesotrophic in winter or spring. Growth and blooms of phytoplankton impacted water quality and self-purification of lakes. Species and quantity of aquatic plants were the main factors to affect the change of pH and dissolved oxygen (DO), and loss of fertilizer and domestic wastewater were the main reasons for high nitrogen and phosphorus concentrations in lakes. Organic nitrogen was the main portion of TN by using excessive organic fertilizer in summer, NO3(-)-N was the main portion in other seasons. The principal component analysis result showed that the three principal components of self-purification ability were phytoplankton factor (water temperature, pH, permanganate index and Chl-a), farm drainage factor (pH, DO and TN), nutrient factor (TN and TP). The cluster analysis result showed that the water quality of four seasons in 11 sampling sites of three lakes could be divided into two categories: first, in spring, autumn and winter; second, in summer. This was caused by the temperature changes and agricultural drainage. Water temperature and pH were used to calculate the concentrations of permanganate index, TN, TP, Chl-a by linear equations, which improved the quick prediction ability in locale.


Assuntos
Biodegradação Ambiental , Monitoramento Ambiental , Água Doce/análise , Poluentes Químicos da Água/análise , Purificação da Água , China , Análise de Componente Principal , Estações do Ano
16.
Chemosphere ; 81(9): 1118-23, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20934201

RESUMO

The current trend of global warming is expected to stimulate the expansion of harmful cyanobacteria blooms. Previously, the occidental type of barley straw has been used to control blooms in Europe and America, but very little is known about the antialgal abilities of its oriental relative. We tested the use of Tibetan hulless barley straw--the progenitor of oriental barley--to inhibit the growth of cyanobacterium Microcystis aeruginosa. Flow cytometry allowed assessment at single-cell level, with morphologic parameters (cell volume, cell membrane integrity) and physiological parameters (in vivo Chlorophyll a fluorescence, metabolic activity) used as endpoints. The reduction of cell densities together with integrated cell membranes suggests that Tibetan barley may act as an algistatic agent. Doses from 2.0 to 8.0 g L⁻¹ of Tibetan barley straw efficiently inhibited the alga, but these doses were much higher than those of occidental barley. Such a large dosage introduced additional nutrients, which stimulated the intracellular metabolic activity and induced two physiological subpopulations in the acute term. After mid and long-term exposure, the growth inhibition effect exceeded the stimulation effect, so that the cells' metabolic activity and Chlorophyll a fluorescence decayed, simultaneously with shrinkage in the algal cell volume.


Assuntos
Recuperação e Remediação Ambiental/métodos , Hordeum , Microcystis/crescimento & desenvolvimento , Clorofila/análise , Clorofila A , Desinfetantes/farmacologia , Eutrofização , Tibet , Purificação da Água/métodos
17.
J Hazard Mater ; 163(2-3): 671-7, 2009 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-18703282

RESUMO

The content and speciation of heavy metals in composted sewage sludge is the main cause of negative impacts on environment and health of animal and human. An aerobic composting procedure was conducted to investigate the influences of some key parameters on phytotoxicity and speciation of Cu, Zn and Pb during sewage sludge composting. The pH value reached the optimal range for development of microorganisms, and content of organic matter (OM) and dissolved organic carbon (DOC) decreased with the composting age. The total amounts of Cu, Zn and Pb were much lower in the final compost. The results from sequential extraction procedure of heavy metals showed that composting process changed the distribution of five fractions of Cu, Zn and Pb, and reduced the total contents and sum percentages of four mobile fractions (exchangeable (EXCH), carbonate (CAR), reducible iron and manganese (FeMnOX), and organic matter bound (OMB)), indicating that the metal mobility and phytotoxicity decreased after aerobic composting. The seed germination and root growth of Pakchoi (Brassica Chinensis L.) were enhanced with composting age and reached the highest value at the end of compost. The decrease of OM and DOC was significantly correlated to changes of metal distribution and germination index (GI) of Pakchoi. Only for Cu in the compost, the GI could be predictable from the sum mobile metal fractions (EXCH+CAR+FeMnOX+OMB) (R=-0.814(*)). For Zn and Pb, R value was significantly increased by use of other components, such as pH, OM and DOC, which suggested that the transformation of heavy metal speciation and phytotoxicity of sewage sludge during an aerobic composting was rather strongly dependent on multiple components than a single element.


Assuntos
Biodegradação Ambiental , Monitoramento Ambiental/métodos , Metais Pesados/análise , Esgotos/microbiologia , Solo/análise , Aerobiose , Brassica , Cobre , Germinação , Chumbo , Metais Pesados/toxicidade , Raízes de Plantas/crescimento & desenvolvimento , Zinco
18.
Huan Jing Ke Xue ; 28(4): 813-8, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17639943

RESUMO

Using a multi-layer soil column device, the effect of new nitrification inhibitor DMPP (3,4-dimethyl pyrazole phosphate) on nitrogen leaching was studied for understanding the nitrogen vertical transformation and lowering the nitrogen leaching losses. The results indicate that, within 60 days of experiment, the regular urea added with 1% of DMPP can effectively inhibit the ammonium oxidation in the soil, and improve the concentration of NH4(+) -N in soil solution over the 20 cm tilth profile, while decline the concentrations of NO3(-) -N and N2(-) -N. No obvious difference is found on NH4(+) -N concentrations collected from deep layer soil solution under 20 cm between regular urea and the urea added with 1% of DMPP. There is also no significant difference for the NH4(+) -N and NO3(-) -N in the soil solution of deep layer under 40 cm among the treatments of urea by adding with 1% of DMPP within 60 days. So DMPP could be used as an effective nitrification inhibitor to control ammonium oxidation, decline the nitrate leaching losses, minimize the underground water pollution risk and be beneficial for the ecological environment.


Assuntos
Nitrogênio/química , Pirazóis/química , Poluentes do Solo/química , Solo/análise , Poluentes do Solo/análise , Movimentos da Água , Poluição da Água/análise , Poluição da Água/prevenção & controle
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