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1.
J Hazard Mater ; 465: 133435, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38224639

ABSTRACT

Nylon-6,6 microplastics (NMPs) in aquatic systems have emerged as potential contaminants to the global environment and have garnered immense consideration over the years. Unfortunately, there is currently no efficient method available to eliminate NMPs from sewage. This study aims to address this issue by isolating Brucella intermedia ZL-06, a bacterium capable of producing a bacterial polysaccharide-based flocculant (PBF). The PBF generated from this bacterium shows promising efficacy in effectively flocculating NMPs. Subsequently, the precipitated flocs (NMPs + PBF) were utilized as sustainable feedstock for synthesizing PBF. The study yielded 6.91 g/L PBF under optimum conditions. Genome sequencing analysis was conducted to study the mechanisms of PBF synthesis and nylon-6,6 degradation. The PBF exhibited impressive flocculating capacity of 90.1 mg/g of PBF when applied to 0.01 mm NMPs, aided by the presence of Ca2+. FTIR and XPS analysis showed the presence of hydroxyl, carboxyl, and amine groups in PBF. The flocculation performance of PBF conformed to Langmuir isotherm and pseudo-first-order adsorption kinetics model. These findings present a promising approach for reducing the production costs of PBF by utilizing NMPs as sustainable nutrient sources.


Subject(s)
Brucella , Caprolactam/analogs & derivatives , Microplastics , Polymers , Plastics , Sewage/microbiology , Flocculation
2.
BMC Cancer ; 24(1): 30, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38166779

ABSTRACT

OBJECTIVE: To illustrate the status of all cancer clinical trials and characterize clinical trial enrollment disparities in the most common cancer. METHODS: Clinical trial data were extracted from ClinicalTrials.gov website. All searched clinical trials were included in the current status analysis of clinical trials on cancer. Among all the clinical trials, only trials addressing single disease sites of breast, prostate, colorectal, or lung (BPCRL) cancer were included in the age disparities analysis. The difference in median age (DMA) between the trial participant median age and the population-based disease-site-specific median age was calculated for each trial. RESULTS: A total of 7747 clinical trials were included in the current status analysis of clinical trials on cancer. The number of registered trials had been increasing from 2008 to 2021 (AAPC = 50.60, 95% CI 36.60, 66.00, P < 0.05). Of the 7747 trials, 1.50% (116) of the studies were clinical trials for the elderly aged 60 years or older. 322 trials were included in the age disparities analysis. For all trials, the median DMA was - 8.15 years (P25, P75, - 10.83 to - 2.98 years, P < 0.001). The median DMA were - 9.55 years (P25, P75, - 11.63 to - 7.11 years), - 7.10 years (P25, P75, - 9.80 to - 5.70 years), - 9.75 years (P25, P75, - 11.93 to - 7.35 years), 3.50 years (P25, P75, 0.60 to 4.55 years), respectively, for breast cancer, colorectal cancer, lung cancer and prostate cancer. CONCLUSION: The numbers of registered clinical trials show an upward trend. Age disparities between trial participants and diagnosed disease population are present in BPCRL cancer trials and appear to be increasing over time. Equitable participation in clinical trials on the basis of age is crucial for advancing medical knowledge and evaluating the safety and efficacy of new treatments that are generalizable to aging populations.


Subject(s)
Breast Neoplasms , Lung Neoplasms , Prostatic Neoplasms , Male , Aged , Humans , Lung Neoplasms/therapy , Breast Neoplasms/epidemiology , Breast Neoplasms/therapy
3.
Sci Total Environ ; 815: 152576, 2022 Apr 01.
Article in English | MEDLINE | ID: mdl-34995608

ABSTRACT

Recalcitrant dissolved organic carbon (RDOC) resulting from microbial carbon (MCPs) holds promise as a relatively long-term natural carbon sink in marine environments. However, the RDOC formation mechanism remains uncertain in terrestrial aquatic systems. To determine the microbial impacts on autochthonous dissolved organic carbon (DOC), RDOC formation, and the critical influencing bacteria species, spatial changes in hydrochemistry, carbon isotopes, and microbial diversity were investigated in water samples from the karstic Lijiang River, southwest China. Samples were collected at various locations along the river system in May and July 2017. The biodegradable DOC (BDOC), RDOC, soil sourced DOC (SDOC), submerged aquatic vascular plant sourced DOC (PDOC) and microbial sourced DOC (MDOC) were calculated using the in-situ microbial incubation method, stable carbon isotopes and C/N ratio. RDOC accounted for 67% to 93% of DOC concentrations, measuring 1.3 mg/L and 1.2 mg/L in May and July, respectively. In May, BDOC concentrations increased by 0.05 mg/L from 0.18 mg/L to 0.23 mg/L, but decreased by 0.43 mg/L from 0.66 mg/L to 0.23 mg/L in July. The spatiotemporal variation of BDOC indicated photosynthesis was the main BDOC source and induced high autochthonous DOC formation, especially in May. However, RDOC was the dominant accumulation component in Lijiang River. MDOC increased by 0.86 mg/L from 0 to 0.86 mg/L in May and 0.78 mg/L from 0.10 mg/L to 0.88 mg/L in July, which was the dominant accumulated DOC and RDOC component. The abundance of Sporichthyaceae accounted for 3.4%-22.6% in May and Novosphingobium accounted for 3.5%-34.0% in July. These were the critical bacteria species induced MDOC formation, which were confirmed by their abundances in KEGG pathway modules determined by PICRUAST2. These results demonstrate that heterotrophic bacteria dominate autochthonous DOC and RDOC formation in the karst surface river, which is valuable for understanding organic carbon cycling in karstic aquatic systems.


Subject(s)
Dissolved Organic Matter , Rivers , Bacteria , Carbon , Carbon Sequestration
4.
Sci Total Environ ; 811: 152375, 2022 Mar 10.
Article in English | MEDLINE | ID: mdl-34914990

ABSTRACT

Human interventions such as tunnel construction have caused groundwater depletion, which substantially affected the functions of forest tree species and their communities. However, the extent to which tunneling-induced groundwater depletion (TIGD) degrades their function levels at various spatial-temporal scales under varying climate conditions remains still unclear. Researchers used stand-scale dendrological records to track and extract the effects of TIGD associated with a single or series of tunneling events (three tunneling events during 1999-2001, 2006-2008, and 2010-2013) on short- and long-term growth levels of two dominant drought-tolerant tree species across (karst and non-karst) landscapes affected by tunnel construction and landscapes not subjected to tunnel construction in a mountainous forest ecosystem located in the southwest of China. The results showed that growth responses of both trees stand to TIGD, and the TIGD-linked water losses of other available water sources were negative and widespread across tunnel-affected landscapes, particularly in the karst landscapes known as delicate landscapes. Tree stands with faster (more vigorous) growth rates showed more significant adverse growth levels in response to either tunneling-induced or drought-induced water stresses. Also, they showed the highest recovered growth levels in response to favorable climatic conditions. Moreover, the growth level in the tunnel-affected forest never fully recovered during six years of very wet weather (2012-2018) after the construction of the final (third) tunnel in 2010-2013. Current research shows that tunnel construction has a cumulatively detrimental impact on the long-term survival of the forest. Even with the mediation of long-term very wet circumstances, it can substantially restrict the development dynamics of the forest compared to drought.


Subject(s)
Groundwater , Trees , Droughts , Ecosystem , Forests , Humans
5.
J Environ Manage ; 294: 113026, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34119990

ABSTRACT

High cost is one of the limiting factors in the industrial production of bioflocculant. Simultaneous preparation of bioflocculant from the contaminants in wastewater was considered as a potential approach to reduce the production cost. In this study, caprolactam was verified as sole feedstock for the growth of strain Alcaligenes faecalis subsp. phenolicus ZY-16 in batch experiments. Chemical analysis showed that the as-prepared MBF-16 consisted of heteropolysaccharides (88.3%) and peptides (9.4%). XPS result indicated the plentiful acylamino, hydroxyl and amino groups in MBF-16, which have an indispensable role in amoxicillin flocculation. The flocculation of amoxicillin can be well stimulated by Freundlich isotherm equation, and the Kf was up to 178.6524 for amoxicillin. The kinetic fitting results proved that the flocculation of amoxicillin by MBF-16 was chemisorbed. This contribution may develop a novel technology for the preparation of bacterial flocculants that can consume toxic substrates (caprolactam) and have potential applications in amoxicillin removal.


Subject(s)
Caprolactam , Alcaligenes , Amoxicillin , Flocculation , Hydrogen-Ion Concentration , Wastewater
6.
Environ Sci Pollut Res Int ; 27(17): 21299-21310, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32266624

ABSTRACT

Surface water suffering from nitrate (NO3-) contamination in karst area is not only harmful to human health as drinking water but can also affect the process of carbonate rock weathering, so it is crucial to trace the sources and transformations of NO3- in karst surface water. In this study, an investigation of water chemical data and NO3- isotopes (δ15N and δ18O) was used to elucidate the transformations of NO3- and quantify a proportional apportionment of NO3- sources of individual potential sources (incl. soil organic nitrogen (SON), atmospheric precipitation (AP), manure and sewage wastes (M&S), and chemical fertilizer (CF)) in the Lijiang River (typical karst surface water), Guilin, Southwest China. δ15N-NO3- and δ18O-NO3- values of water samples from the Lijiang River range from 2.14 to 13.50‰ (mean, 6.59‰) and from - 2.44 to 6.97‰ (mean, 3.76‰), respectively. A positive correlation between Cl- and NO3- but no correlations between NO3- and δ15N-NO3- or δ18O-NO3- are found and the δ18O-NO3- values fitted the theoretical δ18O-NO3- values produced from nitrification, suggesting that the genesis of NO3- in waters of the Lijiang River is affected by nitrification processes and the mixing process has a major effect on NO3- transportation. Results of the Bayesian stable isotope mixing model show that the M&S and SON are the main NO3- source through the whole year (accounting for ~ 61% and 65% of the total NO3- in the wet and dry season, respectively), followed by CF (~ 29%). Furthermore, we find that nitrification of nitrogen in fertilizers, soil, and manure and sewage can promote the carbonate rock weathering. The estimated contribution of such nitrification to the weathering of carbonate rocks accounts for about 11% of the total carbonate rock weathering flux (calculated by HCO3-) in the Lijiang River. This finding indicates that the weathering of carbonate rock is probably affected by nitrogen nitrification processes in karst catchment.


Subject(s)
Environmental Monitoring , Water Pollutants, Chemical/analysis , Bayes Theorem , China , Nitrates/analysis , Nitrogen Isotopes/analysis , Rivers
7.
Am J Obstet Gynecol ; 223(2): 248.e1-248.e21, 2020 08.
Article in English | MEDLINE | ID: mdl-32017922

ABSTRACT

BACKGROUND: There is controversy about whether the amniotic fluid contains bacteria. With the use of sequencing-based methods, recent studies report that the amniotic fluid is colonized by microorganisms. However, background-contaminating DNA might lead to false-positive findings when such a low microbial biomass sample is examined. OBJECTIVE: The purpose of this study was to determine whether the midtrimester amniotic fluid of patients who subsequently had normal pregnancy outcomes contains a microbial signature. STUDY DESIGN: In this prospective cohort study, 42 amniotic fluid samples were collected from 37 pregnancies (5 twin and 32 singletons) during genetic amniocentesis in the midtrimester. The subsequent pregnancy outcomes of all the participants were followed. Multiple methods were used to detect the presence of microorganisms in this study, which included cultivation, quantitative real-time polymerase chain reaction, and 16S ribosomal RNA gene sequencing. Multiple positive control samples (n=16) served as quality control samples and included 3 adult fecal samples, 4 vaginal swabs, and 9 artificial bacterial communities that were run in parallel with negative control samples (n=12) that included 4 samples from the hospital operating room and 8 samples from the laboratory, to account for background-contaminating DNA during each step of the experiments. RESULTS: No bacteria under anaerobic or aerobic conditions or genital mycoplasmas were cultured from any of the amniotic fluid samples. Quantitative polymerase chain reaction did not reveal greater copy numbers of 16S ribosomal RNA gene in amniotic fluid samples than in negative control samples. 16S Ribosomal RNA gene sequencing did not indicate a significant difference in the microbial richness or community structures between amniotic fluid and negative control samples. CONCLUSION: With multiple methods of microbiologic inquiry, no microorganisms were identified in the midtrimester amniotic fluid of healthy pregnancies with a normal pregnancy outcome.


Subject(s)
Amniotic Fluid/microbiology , Culture Techniques/methods , Pregnancy Trimester, Second , RNA, Ribosomal, 16S/analysis , Real-Time Polymerase Chain Reaction/methods , Adult , Amniocentesis , Amniotic Fluid/immunology , Chorioamnionitis/epidemiology , Cohort Studies , Cytokines/analysis , Cytokines/immunology , Female , Fetal Membranes, Premature Rupture/epidemiology , Humans , Pregnancy , Pregnancy Outcome , Premature Birth/epidemiology , Prospective Studies
8.
Huan Jing Ke Xue ; 40(3): 1222-1235, 2019 Mar 08.
Article in Chinese | MEDLINE | ID: mdl-31087969

ABSTRACT

This study was done to understand the diel variation and factors influencing the hydrochemistry of the Lijing River in different seasons. This is a typical medium river located at Guilin City in the Guangxi Zhuang Autonomous Region, SW China. The Shengli site was selected for this study. Two-day monitoring work with a high resolution rate logger and high frequency sampling at 2 hour intervals was conducted at the Shengli site of the Lijiang River in summer and autumn separately. Physical and hydrogeochemical parameters including pH, dissolved oxygen (DO), water temperature (T), electrical conductivity (EC), dissolved inorganic carbon (DIC), isotopes, and other chemical parameters were examined. The results show that:① the physical and hydrochemical parameters[T, pH, DO, SIC, EC, p (CO2)] and major ions (HCO3-, Ca2+) at the Shengli site displayed regular diel variation during monitoring. The data for T, pH, DO, and SIC increased in daylight and decreased at night, while the data for Ca2+, HCO3-, EC, and p (CO2) decreased in daylight and increased at night. ② The diurnal changes of nutrient elements (SO42-, NO3-, Cl-, Na+, Mg2+, and K+) at the Shengli site were mainly controlled by photosynthesis and respiration of aquatic plants, and showed the trend of decrease in daylight and increase at night. Due to the influence of a flood in mid-August 2017, the amount of diurnal variation in the nutrient element levels in summer was less than that in autumn. ③ The δ13CDIC increased in daylight and decreased at night both in summer and autumn, reflecting the influences of photosynthesis and precipitation. Under the influence of different root systems, soil microbial respiration intensity, and seasonal variation of river hydrological factors, the δ13CDIC in summer was generally lighter than that in autumn, with average values of -10.08‰ and -8.90‰, respectively. ④ The daily average fixation amount of karst carbon sink caused by aquatic plants was calculated to be 2.12 mmol·L-1 and 0.94 mmol·L-1 for Autumn and Summer, respectively. To sum up, there is a higher efficiency of karst carbon sink caused by aquatic plants in Autumn than that in Summer.

9.
Huan Jing Ke Xue ; 39(4): 1589-1597, 2018 Apr 08.
Article in Chinese | MEDLINE | ID: mdl-29964983

ABSTRACT

Dynamic variations and sources of nitrate during dry season in the Lijiang River were analyzed using the nitrate concentrations and 15 N and 18 O isotope techniques, from the samples obtained from 13 sections in the Lijiang River from September 28, 2016 to December 28, 2016. Results show that the nitrate concentrations range from 0.46 to 18.48 mg·L-1, with an average of 6.18 mg·L-1, and that the nitrate levels are low during the dry season. Nitrate concentrations in the Lijiang River increase slowly from September to December, mainly being influenced by rainfall, runoff, and human activity. Nitrate concentrations in the Lijiang River from upstream to downstream show a trend of "increase-decrease-increase." Nitrate in the Lijiang River during the dry season mainly originates from organic nitrogen in soil, human and animal feces, sewage (largely living sewage), human and animal waste, and tourism. In order to better protect the water quality of the Lijiang River, the urban sewage pipe network must be expanded, in addition to building small sewage treatment facilities and strengthening tourism management and environmental awareness.


Subject(s)
Nitrates/analysis , Rivers/chemistry , Seasons , Water Pollutants, Chemical/analysis , Animals , China , Environmental Monitoring , Humans , Nitrogen Isotopes , Oxygen Isotopes , Sewage , Soil/chemistry , Water Quality
10.
PLoS One ; 13(2): e0188869, 2018.
Article in English | MEDLINE | ID: mdl-29451896

ABSTRACT

OBJECTIVE: Hypomyelinating disorders are a group of clinically and genetically heterogeneous diseases characterized by neurological deterioration with hypomyelination visible on brain MRI scans. This study was aimed to clarify the clinical and genetic features of HMDs in Chinese population. METHODS: 119 patients with hypomyelinating disorders in Chinese population were enrolled and evaluated based on their history, clinical manifestation, laboratory examinations, series of brain MRI with follow-up, genetic etiological tests including chromosomal analysis, multiplex ligation probe amplification, Sanger sequencing, targeted enrichment-based next-generation sequencing and whole exome sequencing. RESULTS: Clinical and genetic features of hypomyelinating disorders were revealed. Nine different hypomyelinating disorders were identified in 119 patients: Pelizaeus-Merzbacher disease (94, 79%), Pelizaeus-Merzbacher-like disease (10, 8%), hypomyelination with atrophy of the basal ganglia and cerebellum (3, 3%), GM1 gangliosidosis (5, 4%), GM2 gangliosidosis (3, 3%), trichothiodystrophy (1, 1%), Pol III-related leukodystrophy (1, 1%), hypomyelinating leukodystrophy type 9 (1, 1%), and chromosome 18q deletion syndrome (1, 1%). Of the sample, 94% (112/119) of the patients were genetically diagnosed, including 111 with mutations distributing across 9 genes including PLP1, GJC2, TUBB4A, GLB1, HEXA, HEXB, ERCC2, POLR3A, and RARS and 1 with mosaic chromosomal change of 46, XX,del(18)(q21.3)/46,XX,r(18)(p11.32q21.3)/45,XX,-18. Eighteen novel mutations were discovered. Mutations in POLR3A and RARS were first identified in Chinese patients with Pol III-related leukodystrophy and hypomyelinating leukodystrophy, respectively. SIGNIFICANCE: This is the first report on clinical and genetic features of hypomyelinating disorders with a large sample of patients in Chinese population, identifying 18 novel mutations especially mutations in POLR3A and RARS in Chinese patients, expanding clinical and genetic spectrums of hypomyelinating disorders.


Subject(s)
Genetic Heterogeneity , Hereditary Central Nervous System Demyelinating Diseases/epidemiology , China/epidemiology , Chromosome Banding , Female , Hereditary Central Nervous System Demyelinating Diseases/diagnostic imaging , Hereditary Central Nervous System Demyelinating Diseases/genetics , Hereditary Central Nervous System Demyelinating Diseases/pathology , Humans , Infant , Infant, Newborn , Karyotyping , Magnetic Resonance Imaging , Male
11.
Oncol Lett ; 14(4): 4605-4612, 2017 Oct.
Article in English | MEDLINE | ID: mdl-29085459

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is a devastating malignant disease with a poor prognosis. PDAC is known to be difficult to diagnose at an early stage and to exhibit poor recurrence-free prognosis, but there is also a lack of effective treatment and limited knowledge of its biological characteristics. Therefore, there is an urgent requirement for an improved understanding of the cellular or molecular properties associated with PDAC, and to explore novel avenues for the diagnosis and treatment of this disease. In the present study, the microRNA (miRNA/miR) profiles of sera and tumor samples from patients with PDAC and healthy controls were investigated by miRNA microarray, and the potential role of miR-1 expression in PDAC was determined. A total of 43 patients attending the clinic diagnosed with PDAC at Changzhi City People's Hospital were invited to participate. Blood and surgical tumor samples were obtained for analysis by miRNA microarray and the reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The surgical tumor tissue was additionally used to determine miRNAs status by in situ hybridization (ISH). The results of microarray revealed that: i) 27 miRNAs in the sera and 23 miRNAs in the tumor tissues obtained from patients with PDAC were different compared with their matched controls; ii) miR-1, miR-10b and miR-214 were significantly altered in the PDAC group, either in the sera or tumor tissue samples. Results from the RT-qPCR, which detected the levels of miRNAs in patients with PDAC, confirmed those obtained from the miRNA microarray. In particular, the results of the present study revealed that decreased miR-1 and increased miR-214 in the PDAC tissues were associated with the clinicopathological features and survival rates of patients with PDAC. The results of the present study indicated that miRNAs serve an important role in PDAC carcinogenic progression and supplied useful markers, including miR-1, miR-214 and miR-10b, for determining PDAC prognosis using noninvasive methods.

12.
Colloids Surf B Biointerfaces ; 159: 712-719, 2017 Nov 01.
Article in English | MEDLINE | ID: mdl-28881298

ABSTRACT

Bioflocculants are widely used in a large variety of applications, because of their wide range of flocculation. There is limited information in the literature about the ability of bioflocculants to perform beneficial functions without having adverse effects on blood components. In this study, general hemocompatibility of a bioflocculant (MBF-06) was investigated in an in vitro system, measuring flocculation of plasma proteins, red blood cell integrity, blood cell counts, platelet activation, clot formation, complement activation, cytotoxicity and inflammatory response. Effects of MBF-06 included low plasma protein flocculation, low platelet activation, low inflammatory response, no hemolysis or cytotoxicity and increased expression of coagulation markers, including prothrombin fragments 1+2. These findings suggested that the rapid hemostasis caused by MBF-06 resulted, essentially, from humoral coagulation. Overall, our observations revealed the great potential of MBF-06 as a novel hemostatic agent.


Subject(s)
Polysaccharides/chemistry , Blood Coagulation/physiology , Blood Proteins/chemistry , Flocculation , Hemolysis/drug effects , Hemostasis/drug effects , Humans , Platelet Activation/drug effects , Prothrombin/chemistry
13.
Huan Jing Ke Xue ; 38(8): 3200-3208, 2017 Aug 08.
Article in Chinese | MEDLINE | ID: mdl-29964927

ABSTRACT

This study selected a larger typical karst basin, that of Lijiang River, as the research subject and studied the sources of organic carbon in the Lijiang basin in July, August, and September in 2016 by an isotope tracer method, a correlational analysis method, and endmember mixture model, using a stable isotope of carbon and the organic carbon to nitrogen ratio. The results showed the following. ① The spatial distribution characteristics of DIC concentration were as follows: karst area> karst and non-karst mixed area> non-karst area. The content of DIC downstream was higher than upstream. The spatial distribution of DIC concentration was mainly controlled by the distribution of carbonate rocks in the Lijiang basin. ② DOC was the main part of TOC in the Lijiang basin. TOC was mainly derived from the primary productivity of aquatic organisms. The spatial distribution characteristics of autochthonous organic carbon content were as follows: karst area> karst and non-karst mixed area> non-karst area, which may be related to more lush aquatic plants in the karst area than in the non-karst area and the carbonic anhydrase activity in the karst area being higher than in the non-karst area. The content of autochthonous organic carbon in the TOC ranged from 1.02 to 5.14 mg·L-1, with an average of 2.54 mg·L-1. There was no significant spatial difference of the proportion of autochthonous organic carbon in the TOC; it ranged from 51.68% to 85.99%, with an average of 73.07%. ③ The POC concentration, the content of autochthonous organic carbon in the POC, and the proportion of autochthonous organic carbon in the POC had no significant spatial differences. The main source of POC was allochthonous organic carbon, and the content of autochthonous organic carbon in the POC ranged from 0.01 to 0.16 mg·L-1, with an average of 0.05 mg·L-1. The proportion of autochthonous organic carbon in the POC ranged from 3.69% to 41.94%, with an average of 17.31%. ④ The spatial distribution of the content of DOC and autochthonous organic carbon in the DOC are as follows: karst area>karst and non-karst mixed area>non-karst area. DOC mainly came from the primary productivity of aquatic organisms. The content of autochthonous organic carbon of the DOC ranged from 0.97 to 5.10 mg·L-1, with an average of 2.48 mg·L-1. The spatial distribution of the proportion of autochthonous organic carbon in the DOC had no obvious difference and ranged from 54.43% to 94.69%, with an average of 79.51%. Studying the influence of aquatic photosynthetic organisms on organic carbon in rivers can provide basis for scientific problem solution of the stability of karst carbon sinks.

14.
Huan Jing Ke Xue ; 38(10): 4108-4119, 2017 Oct 08.
Article in Chinese | MEDLINE | ID: mdl-29965194

ABSTRACT

The influence of human activities on karst surface water quality has received increasing attention. To explore the impact of human activities on water-rock interactions in karst surface water, water samples were collected from July to November in 2016 in the Lijiang River, which is dominated by human activities. The samples were analyzed for the hydrochemistryand the characteristics of δ13CDIC. The results show that:①The Lijiang River is mainly characterized by HCO3-Ca chemical composition.. The SO42- and NO3- concentrations are inferior to HCO3- concentrations in the anion composition; besides, the concentrations of SO42- and NO3- in the river between Guilin and Yangshuo are higher than in the other sampling sites, caused by tourism and urban development. ②Equivalent ratios of[Ca2++Mg2+]/[HCO3-] are between 1.01 and 1.51 and the equivalent ratios of[Ca2++Mg2+]/[SO42-+NO3-+HCO3-] are between 0.85 and 1.12, indicating that the sulfuric acid and nitric acid have participated in the water-rock interaction. ③The proportions of carbonic acid dissolving carbonate rocks range from 32.10%-98.01% with an average of 75.89%. The proportions of sulfuric acid and nitric acid dissolving carbonate rocks vary from 1.99%-67.90% with an average of 24.11%. The proportions of sulfuric acid and nitric acid dissolving carbonate rocks in the rainy period with an average of 24.31% is higher than in the brief rain period with an average of 23.88%. In addition, the proportions of sulfuric acid and nitric acid dissolving carbonate rocks present a fluctuated increasing trend from upstream to downstream and the maximum strength and the minimum strength of the sulfuric and nitric acid dissolving carbonate rocks occur in Lingchuan and Huajiang, respectively. ④ HCO3- mainly originated from the carbonate rocks dissolved by carbonic acid, with an average of 83.58%, followed by the carbonate rocks dissolved by sulfuric acid and nitric acid, with an average of 14.24%. The contribution of carbonic acid weathering silicate rocks is the smallest with an average of 2.18%. ⑤ δ13CDIC of the Lijiang River ranges from -11.95‰--7.61‰; the calculated δ13CDIC-rock using the mixture endmember model ranges from -14.24‰--7.23‰. δ13CDIC is close to δ13CDIC-rock in the rainy period and δ13CDIC is significantly higher than δ13CDIC-rock in the brief rain period. The difference between δ13CDIC and δ13CDIC-rock is caused by the influence of aquatic photosynthetic organisms.

15.
Article in English | MEDLINE | ID: mdl-27738446

ABSTRACT

Objective. To investigate the absorption property of the representative hydrolyzable tannin, namely corilagin, and its hydrolysates gallic acid (GA) and ellagic acid (EA) from the Fructus Phyllanthi tannin fraction (PTF) in vitro. Methods. Caco-2 cells monolayer model was established. Influences of PTF on Caco-2 cells viability were detected with MTT assay. The transport across monolayers was examined for different time points, concentrations, and secretory directions. The inhibitors of P-glycoprotein (P-gp), multidrug resistance proteins (MRPs), organic anion transporting polypeptide (OATP) and sodium/glucose cotransporter 1 (SGLT1), and tight junction modulators were used to study the transport mechanism. LC-MS method was employed to quantify the absorption concentration. Results. The apparent permeability coefficient (Papp) values of the three compounds were below 1.0 × 10-6 cm/s. The absorption of corilagin and GA were much lower than their efflux, and the uptake of both compounds was increased in the presence of inhibitors of P-gp and MRPs. The absorption of EA was decreased in the company of OATP and SGLT1 inhibitors. Moreover, the transport of corilagin, GA, and EA was enhanced by tight junction modulators. Conclusion. These observations indicated that the three compounds in PTF were transported via passive diffusion combined with protein mediated transport. P-gp and MRPs might get involved in the transport of corilagin and GA. The absorption of EA could be attributed to OATP and SGLT1 protein.

16.
J Environ Manage ; 172: 71-6, 2016 May 01.
Article in English | MEDLINE | ID: mdl-26921567

ABSTRACT

A novel bioflocculant (MBF-79) prepared using formaldehyde wastewater as carbon resource was investigated in the study. The optimal conditions for bioflocculant production were determined to be an inoculum size of 7.0%, initial pH of 6.0, and formaldehyde concentration of 350 mg/L. An MBF-79 of 8.97 g/L was achieved as the maximum yield. Three main elements, namely C, H, and O, were present in MBF-79 with relative weigh percentages of 39.17%, 6.74%, and 34.55%, respectively. The Gel permeation chromatography analysis indicated that the approximate molecular weight (MW) of MBF-79 was 230 kDa. MBF-79 primarily comprised polysaccharide (71.2%) and protein (27.9%). Additionally, conditions for the removal of arsenic by MBF-79 were found to be MBF-79 at 120 mg/L, an initial pH 7.0, and a contact time 60 min. Under the optimal conditions, the removal efficiencies of arsenate (0.5 mg/L) and arsenite (0.5 mg/L) were 98.9% and 84.6%, respectively. Overall, these findings indicate bioflocculation offers an effective alternative method of decreasing arsenic during water treatment.


Subject(s)
Arsenic/isolation & purification , Formaldehyde/chemistry , Wastewater/microbiology , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Arsenates/isolation & purification , Arsenic/chemistry , Arsenites/isolation & purification , Carbon/metabolism , Flocculation , Hydrogen-Ion Concentration , Sewage/microbiology , Wastewater/chemistry
17.
Acta Pharmacol Sin ; 36(6): 758-68, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25864648

ABSTRACT

AIM: Fructus phyllanthi tannin fraction (PTF) from the traditional Tibetan medicine Fructus phyllanthi has been found to inhibit lung and liver carcinoma in mice. In this study we investigated the anticancer mechanisms of PTF in human lung squamous carcinoma cells in vitro. METHODS: Human lung squamous carcinoma cell line (NCI-H1703), human large-cell lung cancer cell line (NCI-H460), human lung adenocarcinoma cell line (A549) and human fibrosarcoma cell line (HT1080) were tested. Cell viability was detected with MTT assay. Cell migration and invasion were assessed using a wound healing assay and a transwell chemotaxis chambers assay, respectively. Cell apoptosis was analyzed with flow cytometric analysis. The levels of apoptosis-related and metastasis-related proteins were detected by Western blot and immunofluorescence. RESULTS: PTF dose-dependently inhibited the viability of the 3 human lung cancer cells. The IC50 values of PTF in inhibition of NCI-H1703, NCI-H460, and A549 cells were 33, 203, and 94 mg/L, respectively. PTF (15, 30, and 60 mg/L) dose-dependently induced apoptosis of NCI-H1703 cells. Treatment of NCI-H1703 and HT1080 cells with PTF significantly inhibited cell migration, and reduced the number of invasive cells through Matrigel. Furthermore, PTF dose-dependently down-regulated the expression of phosphor-ERK1/2, MMP-2 and MMP-9, up-regulated the expression of phosphor-JNK, but had no significant effect on the expression of ERK1/2 or JNK. CONCLUSION: PTF induces cell apoptosis and inhibits the migration and invasion of NCI-H1703 cells by decreasing MPPs expression through regulation of the MAPK pathway.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Apoptosis/drug effects , Carcinoma, Squamous Cell/drug therapy , Cell Movement/drug effects , Drugs, Chinese Herbal/pharmacology , Lung Neoplasms/drug therapy , MAP Kinase Signaling System/drug effects , Matrix Metalloproteinases/metabolism , Mitogen-Activated Protein Kinases/metabolism , Tannins/pharmacology , Carcinoma, Squamous Cell/enzymology , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Cell Survival/drug effects , Dose-Response Relationship, Drug , Enzyme Activation , Extracellular Signal-Regulated MAP Kinases/metabolism , Humans , Inhibitory Concentration 50 , JNK Mitogen-Activated Protein Kinases/metabolism , Lung Neoplasms/enzymology , Lung Neoplasms/pathology , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Medicine, Tibetan Traditional , Neoplasm Invasiveness , Phosphorylation , Time Factors
18.
Molecules ; 19(11): 17478-535, 2014 Oct 30.
Article in English | MEDLINE | ID: mdl-25361420

ABSTRACT

Ganoderma triterpenes (GTs) are the major secondary metabolites of Ganoderma lucidum, a traditional Chinese medicine, popularly used for complementary cancer therapy. GTs are lanostane-tetracyclic triterpenes. They have been reported to possess anti-tumor, anti-inflammation, antioxidant, antimicrobial and blood fat reducing effects. To date, 316 GTs have been found and their similar chemical structures have proved difficult to elucidate. This paper compiles 316 naturally occurring triterpenes from Ganoderma based on the literature published through January 2013 along with their structures, physiological activities and 13C-NMR spectral data.


Subject(s)
Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacology , Ganoderma/chemistry , Triterpenes/chemistry , Triterpenes/pharmacology , Animals , Humans , Mice , Structure-Activity Relationship
19.
Zhongguo Zhong Yao Za Zhi ; 39(7): 1173-8, 2014 Apr.
Article in Chinese | MEDLINE | ID: mdl-25011249

ABSTRACT

This study is to establish the fingerprint for Phyllanthus emblica and their tannin parts from different habitats by HPLC for its quality control. The determination was carried out on a Diamonsil C18 (4.6 mm x 250 mm, 5 microm) column, with methanol-0.2% glacial acetic acid as mobile phase with gradient elution at a flow rate of 1 mL x min(-1). The temperature was maintained at 30 degrees C and the detected wavelength is 260 nm, Thirteen chromatographic peaks were extracted as the common peaks of the fingerprint of P. emblica, and eleven as the common peaks of P. emblica tannin parts, and five peaks were identified by comparing with referent samples. The fingerprints of 8 samples were compared and classified by similarity evaluation, cluster analysis and principal component analysis (PCA). The similarity degrees of eight P. emblica were between 0.763 and 0.993, while tannin parts were between 0.903 and 0.991. All the samples of P. emblica and their tannin parts were classified into 3 categories. The method was so highly reproducible, simple and reliable that it could provide basis for quality control and evaluation of P. emblica from different habitats.


Subject(s)
Drugs, Chinese Herbal/analysis , Phyllanthus emblica/chemistry , Tannins/analysis , Chromatography, High Pressure Liquid , Medicine, Tibetan Traditional , Phyllanthus emblica/classification , Quality Control , Tibet
20.
Bioresour Technol ; 137: 226-32, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23587824

ABSTRACT

This study evaluated the potential of an extracellular, novel biopolymeric flocculant produced by a strain of Klebsiella pneumoniae isolated from a sputum sample for removal of Acanthamoeba cysts, a potent pathogen prevalent in water, soil, air, and dust. The presence of cations did not enhance flocculating activity. The component of MBF-5 was mainly polysaccharide and protein with proportional of 96.8% and 2.1% respectively. Infrared spectrum analysis showed the presence of carboxyl and hydroxyl groups in MBF-5. MBF-5 is nontoxic and can be used for removal of amoebae cysts from water. Conditions for flocculation of kaolin suspension and Acanthamoeba cysts were optimized by response surface methodology (RSM) and determined to be 54.38 mg/L dosage, 26.14°C and pH 3.32 and 129.73 mg/L dosage, 30.75°C and pH 4.36, respectively. The results of this study indicates a possible use of the K. pneumoniae biopolymer as an alternative to typically used chemical flocculants for removal of amoebae cysts from water.


Subject(s)
Acanthamoeba/drug effects , Klebsiella pneumoniae/chemistry , Water Purification/methods , Water/parasitology , Acanthamoeba/isolation & purification , Flocculation , Hydrogen-Ion Concentration , Temperature
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