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1.
Front Psychiatry ; 13: 999007, 2022.
Article in English | MEDLINE | ID: mdl-36090352

ABSTRACT

Background: Genome-wide association studies (GWASs) have identified numerous genetic variants associated with attention-deficit/hyperactivity disorder (ADHD), which is considered highly genetically heritable. However, because most of the variants located in the non-coding region of the human genome, the onset of ADHD requires further exploration. Methods: The risk genes involved in ADHD were identified by integrating GWAS summary data and expression quantitative trait locus (eQTL) data using summary-data-based Mendelian randomization (SMR) method. We then used a stratified linkage disequilibrium score regression (LDSR) method to estimate the contribution of ADHD-relevant tissues to its heritability to screen out disease-relevant tissues. To determine the ADHD-relevant cell types, we used an R package for expression-weighted cell type enrichment (EWCE) analysis. Results: By integrating the brain eQTL data and ADHD GWAS data using SMR, we identified 247 genes associated with ADHD. The LDSR applied to specifically expressed genes results showed that the ADHD risk genes were mainly enriched in brain tissue, especially in the mesencephalon, visual cortex, and frontal lobe regions. Further cell-type-specific analysis suggested that ADHD risk genes were highly expressed in excitatory neurons. Conclusion: The study showed that the etiology of ADHD is associated with excitatory neurons in the midbrain, visual cortex, and frontal lobe regions.

2.
J Cardiovasc Pharmacol ; 78(5): e681-e689, 2021 08 05.
Article in English | MEDLINE | ID: mdl-34354001

ABSTRACT

ABSTRACT: Panax notoginseng saponins (PNS) are commonly used in the treatment of cardiovascular diseases. Whether PNS can protect myocardial ischemia-reperfusion injury by regulating the forkhead box O3a hypoxia-inducible factor-1 alpha (FOXO3a/HIF-1α) cell signaling pathway remains unclear. The purpose of this study was to investigate the protective effect of PNS on H9c2 cardiomyocytes through the FOXO3a/HIF-1α cell signaling pathway. Hypoxia and reoxygenation of H9C2 cells were used to mimic MIRI in vitro, and the cells were treated with PNS, 2-methoxyestradiol (2ME2), and LY294002." Cell proliferation, lactate dehydrogenase, and malonaldehyde were used to evaluate the degree of cell injury. The level of reactive oxygen species was detected with a fluorescence microscope. The apoptosis rate was detected by flow cytometry. The expression of autophagy-related proteins and apoptosis-related proteins was detected by western blot assay. PNS could reduce H9c2 hypoxia-reoxygenation injury by promoting autophagy and inhibiting apoptosis through the HIF-1α/FOXO3a cell signaling pathway. Furthermore, the protective effects of PNS were abolished by HIF-1α inhibitor 2ME2 and PI3K/Akt inhibitor LY294002. PNS could reduce H9c2 hypoxia-reoxygenation injury by promoting autophagy and inhibiting apoptosis through the HIF-1α/FOXO3a cell signaling pathway.


Subject(s)
Cardiovascular Agents/pharmacology , Forkhead Box Protein O3/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Myocardial Reperfusion Injury/prevention & control , Myocytes, Cardiac/drug effects , Panax notoginseng , Plant Extracts/pharmacology , Saponins/pharmacology , Animals , Apoptosis/drug effects , Autophagy/drug effects , Cardiovascular Agents/isolation & purification , Cell Line , Membrane Proteins/metabolism , Mitochondrial Proteins/metabolism , Myocardial Reperfusion Injury/metabolism , Myocardial Reperfusion Injury/pathology , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Panax notoginseng/chemistry , Phosphatidylinositol 3-Kinase/metabolism , Plant Extracts/isolation & purification , Proto-Oncogene Proteins c-akt/metabolism , Rats , Reactive Oxygen Species/metabolism , Saponins/isolation & purification , Signal Transduction
3.
Curr Med Sci ; 41(1): 58-61, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33582906

ABSTRACT

Over 85 590 000 individuals have been infected with severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2). Although there have been an increasing number of reports on coronavirus disease 2019 (COVID-19), it is unclear why infected children show milder symptoms than adults. A retrospective case study was performed at two designated hospitals for COVID-19. Patients (56 children and 63 adults) with confirmed SARS-CoV-2 infection and mild pneumonia were randomly enrolled in this study. The median age of the children was 7.0 years, and 51.79% of them were boys. The median age of the adults was 57 years, and 47.62% were men. The most common symptoms were fever, cough, sputum and diarrhoea. There were no significant differences in symptoms between children and adult patients. In terms of immunological indices on admission, adult patients displayed typical leukopenia and markedly higher levels of IL-2, IL-4, and IL-6 than child patients. The elevation of IL-2, IL-4 and IL-6 in adults induced more extensive lung injury. The effective and non-aggressive immune response successfully resisted SARS-CoV-2 invasion and maintained mild symptoms in child patients. The correlation of higher IL-2, IL-4, and IL-6 with the lung injury might be evidence that preventing excessive cytokine production can avoid further lung damage in these patients.


Subject(s)
COVID-19/immunology , Immunity , Leukopenia/epidemiology , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Interleukin-2/blood , Interleukin-4/blood , Interleukin-6/blood , Male , Middle Aged , Retrospective Studies , Severity of Illness Index
4.
Midwifery ; 91: 102837, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32916595

ABSTRACT

BACKGROUND: Breast milk is the optimal method of human nutrition, and donor human milk is often needed to reduce the incidence of necrotizing enterocolitis and septicemia in preterm infants and improve their survival rate. Donor human milk is recommended as the first alternative when mothers' milk is not available. The establishment of human milk banks is of great significance to promote the breastfeeding of preterm infants. However, there are insufficient studies on human milk banks and milk donation in China. OBJECTIVES: (1) To investigate postpartum women's knowledge, attitude and practice regarding human milk banks and milk donation and to analyze the influencing factors. (2) To explore reasons why postpartum women reject milk donation and donor milk. DESIGN AND SETTINGS: A cross-sectional survey was conducted from February 2019 to July 2019 at two hospitals in Wuhan, a large city in central China. PARTICIPANTS: Mothers who returned to hospital for postpartum follow-up within six months participated in this survey (N = 1078). METHODS: Questionnaires were used to obtain sociodemographic data and to determine participants' knowledge, attitude and practice regarding human milk banks and milk donation. FINDINGS: Of the respondents, 216 (20%) had prior knowledge of human milk banks and milk donation. For the sub-domain of knowledge, the item with the highest correct response rate was the benefit of breast milk, and the item with the lowest correct rate was the acceptance of donor human milk. For the sub-domain of attitude, 811(75.3%) of participants held a supportive attitude for the establishment of human milk banks, and 877(81.3%) were supportive of donating breast milk while 412 (38.3%) were supportive of accepting donor human milk. For the sub-domain of practice, the practice of milk donation was not optimistic as participants lacked interest in donating breast milk and spreading knowledge of breast milk banks, and only 28.3% of participants indicated that they would donate breast milk continuously. Participants' age, educational background, weight of the newborn and having prior knowledge of human milk banks were factors that could positively predict their knowledge, attitude and practice associated with human milk banks and milk donation; medication usage during pregnancy or lactation was a factor negatively predicting their knowledge about human milk banks and milk donation. CONCLUSION: This study reveals that a majority of postpartum women are supportive of human milk banks and more willing to donate breast milk than receive donor milk. Lack of knowledge about human milk banks and safety concerns are the main factors hindering postpartum women from donating or accepting donor milk. Findings suggest that it is important to enhance public awareness regarding human milk banks as potential resources for life-saving therapy for preterm infants.This information should be disseminated during the early stage of the establishment of human milk banks. Moreover, health education of pregnant women should include the importance of human milk as well as the alternative and safety of donor milk from milk banks, especially for promoting the health of preterm infants and infants who are unable to receive mothers' breastmilk.


Subject(s)
Health Knowledge, Attitudes, Practice , Milk Banks , Milk, Human , Postpartum Period/psychology , Adult , China , Cross-Sectional Studies , Female , Humans , Infant , Infant, Newborn , Qualitative Research , Surveys and Questionnaires
5.
J Cardiovasc Pharmacol ; 73(2): 92-99, 2019 02.
Article in English | MEDLINE | ID: mdl-30531436

ABSTRACT

BACKGROUND AND OBJECTIVE: Panax Notoginseng Saponins (PNS) is a formula of Chinese medicine commonly used for treating ischemia myocardial in China. However, its mechanism of action is yet unclear. This study investigated the effect and the mechanism of PNS on myocardial ischemia-reperfusion injury (MIRI) through the hypoxia-inducible factor 1α (HIF-1α)/bcl-2/adenovirus E1B19kDa-interacting protein3 (BNIP3) pathway of autophagy. METHODS: We constructed a rat model of myocardial injury and compared among 4 groups (n = 10, each): the sham-operated group (Sham), the ischemia-reperfusion group (IR), the PNS low-dose group, and the PNS high-dose group were pretreated with PNS (30 and 60 mg/kg, respectively). Serum creatine kinase, malonaldehyde (MDA), lactate dehydrogenase, myocardial tissue superoxide dismutase, and reactive oxygen species were detected in rats with myocardial ischemia-reperfusion after the intervention of PNS. The rat myocardial tissue was examined using hematoxylin and eosin (H&E) staining, and the mitochondria of myocardial cells were observed using transmission electron microscopy. The expressions of microtubule-associated protein light chain 3 (LC3), HIF-1α, BNIP3, Beclin-1, and autophagy-related gene-5 (Atg5) in rat myocardial tissue were detected using Western blotting. RESULTS: The results showed that PNS was significantly protected against MIRI, as evidenced by the decreasing in the concentration of serum CK, MDA, lactate dehydrogenase, and myocardial tissue superoxide dismutase, reactive oxygen species, the attenuation of myocardial tissue histopathological changes and the mitochondrial damages of myocardial cells, and the increase of mitochondria autophagosome in myocardial cells. In addition, PNS significantly increased the expression of LC3 and the ratio of LC3II/LC3I in rat myocardial tissue. Moreover, PNS significantly increased the expression of HIF-1α, BNIP3, Atg5, and Beclin-1 in rat myocardial tissue. CONCLUSIONS: The protective effect of PNS on MIRI was mainly due to its ability to enhance the mitochondrial autophagy of myocardial tissue through the HIF-1α/BNIP3 pathway.


Subject(s)
Autophagy/drug effects , Cardiovascular Agents/pharmacology , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Membrane Proteins/metabolism , Mitochondrial Proteins/metabolism , Myocardial Infarction/prevention & control , Myocardial Reperfusion Injury/prevention & control , Myocytes, Cardiac/drug effects , Panax , Saponins/pharmacology , Animals , Autophagy-Related Protein 5/metabolism , Beclin-1/metabolism , Cardiovascular Agents/isolation & purification , Disease Models, Animal , Male , Microtubule-Associated Proteins/metabolism , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Myocardial Reperfusion Injury/metabolism , Myocardial Reperfusion Injury/pathology , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/ultrastructure , Panax/chemistry , Rats, Sprague-Dawley , Saponins/isolation & purification , Signal Transduction
6.
Medicine (Baltimore) ; 96(49): e9122, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29245349

ABSTRACT

RATIONALE: Though it is rare, isolated interrupted aortic arch (IAA) could lead to hypertension. Surgical repair is the only effective curative method to treat IAA conditions and patients with IAA can hardly survive to adulthood with medication alone. We report an IAA case that of a 45-year-old male patient who survived for 45 years without surgical treatment. PATIENT CONCERNS: A 45-year-old man was referred to the hospital presenting with abnormal blood pressure level. Both computed tomography angiogram (CTA) and angiography revealed IAA. DIAGNOSES: The patient was diagnosed as IAA based on computed tomography angiogram (CTA) and angiography. INTERVENTIONS: The patient's blood pressure was severely high and refractory. He refused surgical treatment and accepted antihypertensive medication for 10 days. OUTCOMES: The patient's office blood pressure level was abnormal, fluctuating between 140/90 and 160/100 mm Hg, but 24-hour ambulatory blood pressure monitoring showed normal level. LESSONS: Hypertension due to IAA could be controlled with medications, even surgery is not performed. The discrepancy between ambulatory and office blood pressure levels may be due to the white coat effect.


Subject(s)
Aorta, Thoracic/pathology , Aortic Arch Syndromes/complications , Hypertension/etiology , Antihypertensive Agents/therapeutic use , Aortic Arch Syndromes/drug therapy , Humans , Male , Middle Aged
7.
Arch Gerontol Geriatr ; 63: 72-7, 2016.
Article in English | MEDLINE | ID: mdl-26586111

ABSTRACT

PURPOSE: To investigate whether mitochondrial DNA (mtDNA) damage, specifically deletion, contributes to the development of atherosclerosis or is simply a secondary effect of the primary factors causing atherosclerosis. MATERIALS AND METHODS: mtDNA deletion was detected by PCR in the aortic root of atherosclerosis-prone C57BL/6J apolipoprotein (Apo) E gene deficient (-/-) mice and control C57BL/6J mice at different ages. Atherosclerotic plaques in the Apo E-/- mice were assessed using frozen sections of the aortic root. The protein levels of COX III and 8-oxoguanine glycosylase (OGG1) were determined. RESULTS: while mtDNA deletions accumulated significantly in mice as young as 2- month-old, atherosclerotic plaques were not detected until mice were 6 months old or older, suggesting that mtDNA deletion occurs prior to the formation of atherosclerotic plaques in the aortic root of these mice. Moreover, the expression levels of mtDNA-encoded COX III protein in both 2-month-old and 16-month-old C57BL/6J ApoE-/- mice were significantly lower than those in C57BL/6J mice (p<0.05). Additionally, the protein level of 8-oxoguanine glycosylase (OGG1), a mitochondrial enzyme that functions in DNA excision repair, decreased with age in these mice, indicating that age-related down-regulation of mtDNA excision repair also contributes to atherosclerosis in C57BL/6J ApoE-/- mice. CONCLUSION: These results reveal that mtDNA deletions occur during the early "initiation" stage of atherosclerosis in C57BL/6J ApoE-/- mice and have the potential to promote atherosclerosis.


Subject(s)
Apolipoproteins E/genetics , Atherosclerosis/etiology , DNA Glycosylases/genetics , DNA, Mitochondrial/genetics , Prostaglandin-Endoperoxide Synthases/genetics , Animals , Atherosclerosis/genetics , Atherosclerosis/metabolism , Down-Regulation , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Polymerase Chain Reaction
8.
Rejuvenation Res ; 12(3): 209-15, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19594329

ABSTRACT

Mitochondrial DNA (mtDNA) damage has been hypothesized to be responsible for aging and various neurological diseases. Abnormalities in 8-oxoguanine DNA glycosylase (OGG1) function can promote DNA oxidative damage, especially in the mitochondria. Here we report changes in the expression of OGG1 targeting to the nucleus, cytosol, and mitochondria in both accelerated senescence mice (SAM-P/8) and normal counterpart SAM-R/1 mice during brain aging. Our results showed that mRNA and protein levels of OGG1, especially OGG1 targeting to mitochondria, and the expression level of cytochrome c oxidase subunit III (COX III) in the brain of both SAM-P/8 mice and SAM-R/1 mice, decreased with age. However, such an age-dependent decrease in SAM-P/8 mice was larger than that in normal SAM-R/1 mice. These findings support the concept that down-regulation of OGG1, especially mitochondrial OGG1(mtOGG1) in SAM-P/8 mice, may promote brain aging by its effect on imbalance in the mtDNA damage repair systems, which leads to accumulation of mtDNA damage and oxidative phosphorylation-related protein dysfunction. Overall, our results provide novel insight into underlying the molecular mechanisms during brain aging.


Subject(s)
Aging , Brain/metabolism , DNA Glycosylases/biosynthesis , Down-Regulation , Gene Expression Regulation, Enzymologic , Animals , DNA, Mitochondrial/metabolism , Gene Deletion , Mice , Oxygen/metabolism , Phosphorylation , RNA, Messenger/metabolism , Reactive Oxygen Species , Reverse Transcriptase Polymerase Chain Reaction , Time Factors
9.
J Environ Manage ; 88(4): 939-46, 2008 Sep.
Article in English | MEDLINE | ID: mdl-17590499

ABSTRACT

In order to explore the pathway of the anaerobic biotreatment of the wastewater containing pentachlorophenol (PCP) and ensure the normal operation of Upflow Anaerobic Sludge Blanket (UASB) reactor, the anaerobic sludge under different acclimation conditions were selected to seed and start up UASB reactors. Anaerobic toxicity assays were employed to study the biological activity, the tolerance and the capacity to degrade PCP of different anaerobic granular sludge from UASB reactors. Results showed that the anaerobic granular sludge acclimated to chlorophenols (CPs) could degrade PCP more quickly (up to 9.50mg-PCP g(-1)TVS d(-1)). And the anaerobic granular sludge without acclimation to CPs had only a little activity of degrading PCP (less than 0.07 mg-PCP g(-1)TVS d(-1)). Different PCP concentrations (2, 4, 6, 8 mg L(-1)) had different inhibition effects on glucose utilization, volatile fatted acidity (VFA)-degrading and methanogens activity of PCP degradation anaerobic granular sludge, and the biological activity declined with the increase in PCP concentration. The methanogens activity suffered inhibition from PCP more easily. The different acclimation patterns of seeded sludge had distinctly different effects on biological activity of the degradation of PCP of anaerobic granular sludge from UASB reactors. The biological activity of the anaerobic granular sludge acclimated to PCP only was also inhibited. This inhibition was weak compared to that of anaerobic granular sludge acclimated to CPs, further, the activity could recover more quickly in this case. In the same reactor, the anaerobic granular sludge from the mid and base layers showed higher tolerance to PCP than that from super layer or if the sludge is unacclimated to CPs, and the corresponding recovery time of the biological activity in the mid and base layers were short. Acetate-utilizing methanogens and syntrophic propinate degraders were sensitive to PCP, compared to syntrophic butyrate degraders.


Subject(s)
Anaerobiosis , Pentachlorophenol/toxicity , Sewage/microbiology , Bioreactors
10.
Wei Sheng Wu Xue Bao ; 47(1): 141-4, 2007 Feb.
Article in Chinese | MEDLINE | ID: mdl-17436641

ABSTRACT

Porcine interferon-gamma (PoIFN-gamma) of Chinese local brand, Meishan porcine, was cloned and inserted into retroviral vector pLXSN (neo r) . Using Lipofectamine, this recombinant plasmid was transfected into retroviral packing cell line, PA317 cells. These transfected cells were selected by DMEM containing 400microg/mL G418 for one week. RNA was extracted from the supernatant of these selected PA317 cells and the PoIFN-gamma gene could be amplified by RT-PCR. Pocine kidney cells and PK-15 cells were infected by the supernatant and were selected by 400 microg/mL, 600 microg/mL and 800 microg/mL G418, respectively. Those PK-15 cells were detected by indirect immunofluorescence assay and it was found that PoIFN-gamma mainly anchored in cellular membrane. The supernatant of the selected PK-15 was tested for the antiviral bioactivity after 48 hours of passage. The anti-VSV (vesicular stomatitis virus) activity in MDBK (bovine kidney cell) was 1200IU/10(6) cells. In addition, the effect of rPoIFNgamma-anti-FMDV was determined using cytopathic effect inhibition. The results indicate that PoIFN-gamma has been inserted into retroviral vector and recombinant retrovirus has been successfully packaged in PA317 cells. Furthermore, this retrovirus can infect PK-15 cells and express PoIFN-gamma with natural antiviral bioactivity and can inhibit VSV and FMDV.


Subject(s)
Genetic Vectors , Interferon-gamma/biosynthesis , Interferon-gamma/genetics , Kidney/metabolism , Retroviridae/genetics , Animals , Fluorescent Antibody Technique, Indirect , Foot-and-Mouth Disease Virus/drug effects , Interferon-gamma/pharmacology , Recombinant Proteins , Swine , Vesicular stomatitis Indiana virus/drug effects
11.
Bioresour Technol ; 98(13): 2526-32, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17071082

ABSTRACT

A sequential upflow anaerobic sludge blanket (UASB) and air-lift loop sludge blanket (ALSB) treatment was introduced into leachate recirculation to remove organic matter and ammonia from leachate in a lab-scale bioreactor landfill. The results showed that the sequential anaerobic-aerobic process might remove above 90% of COD and near to 100% of NH4+ -N from leachate under the optimum organic loading rate (OLR). The total COD removal efficiency was over 98% as the OLR increased to 6.8-7.7 g/l d, but the effluent COD concentration increased to 2.9-4.8 g/l in the UASB reactor, which inhibited the activity of nitrifying bacteria in the subsequent ALSB reactor. The NO3- -N concentration in recycled leachate reached 270 mg/l after treatment by the sequential anaerobic-aerobic process, but the landfill reactor could efficiently denitrify the nitrate. After 56 days operation, the leachate TN and NH4+ -N concentrations decreased to less than 200 mg/l in the bioreactor landfill system. The COD concentration was about 200 mg/l with less than 8 mg/l BOD in recycled leachate at the late stage. In addition, it was found that nitrate in recycled leachate had a negative effect on waste decomposition.


Subject(s)
Aerobiosis , Anaerobiosis , Bioreactors , Environmental Restoration and Remediation/methods , Refuse Disposal , Nitrogen/isolation & purification
12.
Wei Sheng Wu Xue Bao ; 46(1): 158-61, 2006 Feb.
Article in Chinese | MEDLINE | ID: mdl-16579487

ABSTRACT

Porcine circovirus type 2(PCV2) recently emerged as an important infectious pathogen for pigs in the world. Unfortunately, there is no efficient method to deal with PCV2 infection until now. In this study, chimeric porcine circovirus molecular clone (pSK2PCV1-2) was constructed by cloning capsid gene of PCV2 into the backbone of PCV1. PK-15 cells was transfected with pSK2PCV1-2 and then cultivated in plate for five passages. mRNA of PCV1 ORF1 and PCV2 ORF2 were detected in the fifth passage, but mRNA of PCV1 ORF2 and PCV2 ORF1 were not detected in the cells. On the other hand, capsid protein of PCV2 was also detected in the nucleolus of transfected cells by IIF. This study indicated that pSK2PCV1-2 could form infectious virus in transfected cells. It will provide base for further study on biological characteristic of chimeric porcine circovirus.


Subject(s)
Circoviridae Infections/veterinary , Circovirus/genetics , Circovirus/pathogenicity , Swine Diseases/virology , Swine/virology , Animals , Circoviridae Infections/virology , Circovirus/isolation & purification , RNA, Messenger , Reverse Transcriptase Polymerase Chain Reaction
13.
J Hazard Mater ; 136(3): 645-53, 2006 Aug 25.
Article in English | MEDLINE | ID: mdl-16513261

ABSTRACT

Upflow anaerobic sludge blanket (UASB) reactor that was seeded with anaerobic sludge acclimated to chlorophenols was used to investigate the feasibility of anaerobic biotreatment of synthetic wastewater containing pentachlorophenol (PCP) with additional sucrose as carbon source. Two sets of UASB reactors were operated at one time. But the seeded sludge for the two reactors was different and Reactor I was seeded with the sludge that was acclimated to PCP completely for half a year, and Reactor II was seeded with the mixed sludge that was acclimated for half a year to PCP, 4-CP, 3-CP or 2-CP, respectively. The degradation of PCP and the operation fee treating the wastewater are affected by the concentration of MEDS (microorganism easily degradable substrate). So the confirmation of the suitable ratio of [COD] and [PCP] was the key factor of treating the wastewater containing PCP economically and efficiently. During the experiment, the synthetic wastewater with 180.0 mg L(-1) PCP and 1250-10000 mg L(-1) COD could be treated steadily in the experimental Reactor I. The removal efficiency of PCP was more than 99.5% and the removal efficiency of COD was up to 90%. [PCP] (concentration of PCP) in effluent was less than 0.5 mg L(-1). [PCP] in influent could affect proper [COD] (concentration of COD) range in influent that was required for maintenance of steady running of the experimental reactor with a hydraulic retention time (HRT) from 20 to 22 h. [PCP] in influent would directly affect the necessary [COD] in influent when the UASB reactor ran normally and treated the wastewater containing PCP. When [PCP] was 100.4, 151.6 and 180.8 mg L(-1) in influent, respectively, [COD] in influent had to be controlled about 1250-7500, 2500-5000 and 5000 mg L(-1) to maintain the UASB reactor steady running normally and contemporarily ensure that [COD] and [PCP] in effluent were less than 300 and 0.5 mg L(-1), respectively. With the increase of [PCP] in influent, the range of variation of [COD] in influent endured by the UASB reactor was decreasing. The ratios of [COD] and [PCP] in influent could affect removal efficiency of PCP and COD, the concentration of total volatile fatty acids (VFA) in effluent, biogas quantity and methane content in biogas. [PCP] in influent was linearly or semi-logarithmically correlated to [COD] in effluent when [COD] in influent was 5750+/-250 mg L(-1), and so was the relationship between [COD] in influent and [PCP] in effluent when [PCP] in influent was 100.4 or 151.6 mg L(-1), less than the maximum permissible [PCP]. The sources of seeded sludge, the way of sludge acclimation and the characteristics of anaerobic sludge could all affect the UASB reactor capacity treating PCP. When [PCP] were less than 180.8 mg L(-1) for Reactor I and 151.6 mg L(-1) for Reactor II, the variation of [PCP] in influent had little effect on the UASB reactor volume gas production rate and substrate gas production rate. And [VFA] and pH value in effluent were affected a little. Volume biogas production rate and substrate biogas production rate of the UASB reactor were only affected by [COD] and loading rate in influent. But when [PCP] was more than 151.6 mg L(-1) for Reactor II, the biogas production fell quickly and was over 3 days later. [VFA] in effluent from Reactor II increased up to 2198.1 mg L(-1) quickly and the pH value fell to less than 7. Reactor II could not run normally. The component of VFA accumulated quickly was mainly acetate (above 50%). With [PCP] increased from 7.9 to 180.8 mg L(-1) gradually in influent, the methane content in biogas from Reactor II decreased from 70% to 60%, but the reactor could still run normally. Then as for Reactor II, the content of methane have fallen from 75% to 45% or so quickly. And Reactor II could not run steadily. So the conclusion could be drown that too high [PCP] in influent for UASB reactor mainly inhibited the activity of methane-producing bacteria cultures utilizing the acetate.


Subject(s)
Environmental Pollutants/analysis , Oxygen/chemistry , Pentachlorophenol/chemistry , Waste Disposal, Fluid , Algorithms , Anaerobiosis , Chromatography, High Pressure Liquid , Methane/chemistry , Methane/metabolism , Water Microbiology
14.
J Hazard Mater ; 125(1-3): 231-6, 2005 Oct 17.
Article in English | MEDLINE | ID: mdl-15996816

ABSTRACT

PCP-degrading anaerobic granular sludge could be formed in an upflow anaerobic sludge blanket (UASB) reactor that was seeded with anaerobic sludge acclimated to chlorophenol. When hydraulic retention time (HRT) was 20-22 h and PCP loading rate was 200-220 mgL(-1)d(-1), the wastewater containing 170-180 mgL(-1) PCP could be treated effectively in UASB reactor, and PCP removal rate reached up to 99.5%. PCP adsorption and desorption by anaerobic granular sludge follow Freundlich isothermal equation and part of adsorption capacity was not reversible. And the isothermal equation could well describe the variation law of PCP adsorption and desorption by anaerobic granular sludge. The results indicated that the principal removal mechanism of PCP was biodegradation by anaerobic granular sludge, but not adsorption or volatilization.


Subject(s)
Industrial Waste/prevention & control , Pentachlorophenol/isolation & purification , Sewage/chemistry , Water Pollutants, Chemical/isolation & purification , Water Pollution, Chemical/prevention & control , Adsorption , Anaerobiosis , Biodegradation, Environmental , Kinetics , Volatilization
15.
J Hazard Mater ; 119(1-3): 239-43, 2005 Mar 17.
Article in English | MEDLINE | ID: mdl-15752871

ABSTRACT

The effect of microbial easily degradable substrate (MEDS) on the anaerobic degradation of pentachlorophenol (PCP) in two upflow anaerobic sludge blanket (UASB) reactors was investigated. The results indicated that glucose-utilizing activity decreased with the increase of PCP concentration in the mixed culture, and MEDS promoted PCP-dechlorination and degrading activities. The concentration of MEDS increased from 917 to 4580 mg L(-1) with the increase of PCP concentration from 100 to 181 mg L(-1)in influent, which was necessary for maintenance of steady operation of the experimental reactors, the removal rate of PCP and COD ranged up to 99.5 and 90.0% and the concentration of PCP in the effluent was less than 0.5 mg L(-1). The concentration of PCP in effluent was linearly or logarithmically related to sucrose concentration in the influent while PCP was less than the maximum permissible PCP concentration. The activity of anaerobic sludge in the reactor decreased as the concentration of PCP increased, but it could be recovered step by step as time progressed. In the lowest layer of the reactor, the activity of sludge was the highest. So it is feasible to accelerate the degradation of the organic toxic compounds like PCP, by adding suitable quantities of microbial easily degradable substrate to the system.


Subject(s)
Bacteria, Anaerobic , Bioreactors , Environmental Pollutants/metabolism , Pentachlorophenol/metabolism , Biodegradation, Environmental , Biomass
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 22(5): 838-9, 2002 Oct.
Article in Chinese | MEDLINE | ID: mdl-12938444

ABSTRACT

This article introduced a method for the determination of total quantity of rare earths, Ca, Mg, Mn and Fe in rare-earths-magnesium with ICP-AES. The total quantity of rare-earths was calculated by the quantum of cerium, the measurement channel of cerium was fixed by the method of Offset Profile Add Lines, by changing the entrance slit angle, based on the fixed channels of the ICP-AES. The sample was melted with HNO3, HF, HClO4 and HCl, the difficulty of melting sample was properly settled. The method of internal standard was used in the determination, cobalt elected for the internal standard, and the same concentration cobalt liquor was added in the sample liquor. This article made the measurement parameters test, for example the quantum of pump, the height of observation, etc, and examined the liner range, accuracy, background equal concentration, detection limits and precision. The results showed that the method was simpler than chemical analytic method in operating, and could simultaneously determined many kinds of elements. It was compared with chemical method, the results were satisfactory.


Subject(s)
Alloys/chemistry , Calcium/analysis , Magnesium/chemistry , Metals, Rare Earth/chemistry , Iron/analysis , Magnesium/analysis , Manganese/analysis , Spectrophotometry, Atomic/methods
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