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1.
Medicine (Baltimore) ; 103(17): e37898, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669428

RESUMO

Nonischemic cardiomyopathy (NICM) is a major cause of advanced heart failure, and the morbidity and mortality associated with NICM are serious medical problems. However, the etiology of NICM is complex and the related mechanisms involved in its pathogenesis remain unclear. The microarray datasets GSE1869 and GSE9128 retrieved from the Gene Expression Omnibus database were used to identify differentially expressed genes (DEGs) between NICM and normal samples. The co-expressed genes were identified using Venn diagrams. Kyoto Encyclopedia of Genes and Genomes pathway analyses and gene ontology enrichment were used to clarify biological functions and signaling pathways. Analysis of protein-protein interaction networks using Search Tool for the Retrieval of Interacting Genes/Proteins online to define the hub genes associated with NICM pathogenesis. A total of 297 DEGs were identified from GSE1869, 261 of which were upregulated genes and 36 were downregulated genes. A total of 360 DEGs were identified from GSE9128, 243 of which were upregulated genes and 117 were downregulated genes. In the 2 datasets, the screening identified 36 co-expressed DEGs. Kyoto Encyclopedia of Genes and Genomes pathway and gene ontology analysis showed that DEGs were mainly enriched in pantothenate and CoA biosynthesis, beta-alanine metabolism, kinetochore, G-protein beta/gamma-subunit complex, and other related pathways. The PPI network analysis revealed that DUSP6, EGR1, ZEB2, and XPO1 are the 4 hub genes of interest in the 2 datasets. Bioinformatics analysis of hub genes and key signaling pathways is an effective way to elucidate the mechanisms involved in the development of NICM. The results will facilitate further studies on the pathogenesis and therapeutic targets of NICM.


Assuntos
Cardiomiopatias , Biologia Computacional , Mapas de Interação de Proteínas , Cardiomiopatias/genética , Humanos , Biologia Computacional/métodos , Mapas de Interação de Proteínas/genética , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Transdução de Sinais/genética , Ontologia Genética , Bases de Dados Genéticas
2.
J Geriatr Cardiol ; 19(10): 743-752, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36338278

RESUMO

BACKGROUND: Several studies have proved the safety and feasibility of robot-assisted percutaneous coronary intervention (PCI) in reducing the occupational hazards of interventionists while achieving precision medicine. However, an independently developed robot-assisted system for PCI in China has not yet emerged. This study aimed to evaluate the safety and feasibility of a robot-assisted system for elective PCI in China. METHODS: This preclinical trial included 22 experimental pigs and preliminarily supported the safety and feasibility of the ETcath200 robot-assisted system for PCI. Then, eleven patients with coronary heart disease who met the inclusion criteria and had clinical indications for elective PCI were enrolled. PCI was performed using a robot-assisted system. The primary outcomes were clinical success (defined as visual estimated residual stenosis < 30% after PCI and no major adverse cardiovascular events during hospitalization and within 30 days after PCI) and technical success (defined as the ability to use the robot-assisted system to complete PCI successfully without conversion to the traditional manual PCI). RESULTS: Eleven patients were included in this clinical trial. A drug-eluting stent with a diameter of 3 mm (interquartile range: 2.75-3.5 mm) and a length of 26 mm (interquartile range: 22-28 mm) was deployed in all patients. The clinical success rate was 100%, with no PCI-related complications and no in-hospital or 30-day major adverse cardiovascular events, and the technical success rate was 100%. CONCLUSIONS: The results strongly suggest that the use of the independently developed robot-assisted system in China for elective PCI is feasible, safe, and effective.

3.
J Geriatr Cardiol ; 18(11): 877-885, 2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34908925

RESUMO

BACKGROUND: Tanscatheter left atrial appendage (LAA) closure and minimally invasive thoracoscopic LAA occlusion are local interventions of LAA for stroke prevention in patients with nonvalvular atrial fibrillation (NVAF). However, the safety and efficacy of these methods have not been compared. This prospective cohort study aimed to assess the safety and efficacy of those two treatment approaches for stroke prevention in NVAF patients. METHODS: Two hundred and nine recurrent NVAF patients who received radiofrequency ablation were enrolled. These patients were treated with transcatheter LAA closure or thoracoscopic LAA occlusion. The patients were followed up from the first postoperative day and evaluated for efficacy endpoints (stroke/transient ischemic attack (TIA), systemic embolism (SE), and death) and a safety endpoint (bleeding events). Perioperative complications were recorded. RESULTS: After a median follow-up of 1.8 years (383 patient-years), the overall rate of the composite efficacy endpoints was similar between the two groups (3.8 vs. 2.7 events per 100 patient-years; HR = 0.71; 95% CI: 0.225-2.237; P = 0.559). However, regarding primary safety endpoint, there were 1.5 bleeding events per 100 patient-years in the thoracoscopic LAA occlusion group, compared with 6.4 in transcatheter LAA closure group (HR = 0.246; 95% CI: 0.074-0.819; P = 0.022). The incidence of operative complications was 3/138 (2.17%) in thoracoscopic LAA occlusion group and 1/71 (1.41%) in transcatheter LAA closure group. CONCLUSIONS: Thoracoscopic LAA occlusion and transcatheter LAA closure have similar efficacy in preventing stroke in NVAF patients. However, the thoracoscopic group had fewer bleeding events than the transcatheter group, but the former group required a longer hospital stay.

4.
Org Biomol Chem ; 19(38): 8250-8253, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34518849

RESUMO

An atom economical protocol for the construction of 9-(diorganomethylidene)fluorenes through palladium-catalyzed coupling reactions of 2-iodobiphenyls with alkenyl bromides has been reported. The reaction proceeds through the C-H activation/oxidative addition/reduction elimination/intramolecular Heck coupling reaction to afford a series of 9-(diorganomethylidene)fluorenes with good yields. Control experiments demonstrate that a five-membered palladacycle acts as a key intermediate and ß-H elimination serves as the rate-limiting step.

6.
J Mol Model ; 26(7): 190, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32613574

RESUMO

In order to explore the nature of the hydration and swelling of superabsorbent resin, a theoretical investigation into the cooperativity effect of the H-bonding interactions in the hydrates of four model compounds that can be regarded as the units of hydroquinone formaldehyde resin (HFR) (i.e., O-hydroxymethyl-1,4-dihydroxybenzene, methylene di-O-hydroxymethyl-1,4-dihydroxybenzene, p-hydroxy hydroxymethyl calix[4]arene and p-hydroxy hydroxymethyl calix[5]arene) was carried out by many-body interaction and density functional reactivity theory. The HFR···H2O···H2O complexes, in which the H2O···H2O moieties are bound with both the hydroxyl groups of HFR, are the most stable. For the HFR(H2O)n clusters, the interaction energy per building block is increased as the number of the size n increases, indicating the cooperativity effect. Therefore, a deduction is given that the cooperativity effects of the H-bonding interactions play an important role in the process of the hydration and swelling of HFR, and the swelling behavior is mainly attributed to the cooperativity effects which arised from the interactions between the H2O molecules. The origin of the cooperativity effect was examined employing several information-theoretic quantities in the density functional reactivity theory. The degree of swelling of HFR was quantitated using a measure of volume. Graphical abstract.

7.
Cardiovasc Diabetol ; 18(1): 11, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30691501

RESUMO

BACKGROUND: Increasing evidence has suggested that the presence of remnant lipoproteins is a significant risk factor for atherosclerosis. Remnant lipoproteins are lipoproteins that are rich in triglycerides (TGs), and the main components include very-low-density lipoprotein (VLDL) in the fasting state. Diabetic patients often have hypertriglyceridemia with elevated levels of VLDL cholesterol but normal levels of low-density lipoprotein cholesterol (LDL-C). The aim of the present study was to elucidate the potential role of remnant lipoproteins-induced atherosclerosis in the occurrence and development of in-stent restenosis (ISR) in diabetic patients with coronary artery disease. METHODS: The present study enrolled 2312 patients with type 2 diabetes mellitus who underwent percutaneous coronary intervention from January 2013 to December 2014 and who were followed up by angiography. Patients were divided into two groups based on the presence or absence of ISR, and multivariate Cox's proportional hazards regression modelling showed that remnant-like particle cholesterol (RLP-C) was an independent risk factor for ISR. According to the receiver operating characteristic curve, the optimal cutoff point of the RLP-C was identified, and the patients were further divided into 2 groups. Propensity score matching analysis was performed, and 762 pairs were successfully matched. Log-rank tests were used to compare Kaplan-Meier curves for overall follow-up to assess ISR. RESULTS: The multivariate Cox's proportional hazards regression analysis showed that RLP-C was independently associated with ISR, and the baseline RLP-C level at 0.505 mmol/L was identified as the optimal cutoff point to predict ISR. Patients were divided into 2 groups by RLP levels. After propensity score matching analysis, a total of 762 pairs matched patients were generated. Kaplan-Meier curves showed that the estimated cumulative rate of ISR was significantly higher in patients with RLP-C levels ≥ 0.505 mmol/L (log-rank P < 0.001; HR equal to 4.175, 95% CI = 3.045-5.723, P < 0.001) compared to patients with RLP-C levels < 0.505 mmol/L. CONCLUSIONS: The present study emphasized the importance of remnant-like particle cholesterol in cardiovascular pathology in diabetic patients. Physicians should take measures to control RLP-C below the level of 0.505 mmol/L to better prevent of in-stent restenosis in diabetic patients.


Assuntos
Colesterol/sangue , Doença da Artéria Coronariana/cirurgia , Reestenose Coronária/sangue , Diabetes Mellitus Tipo 2/sangue , Lipoproteínas/sangue , Intervenção Coronária Percutânea/efeitos adversos , Triglicerídeos/sangue , Idoso , Pequim/epidemiologia , Biomarcadores/sangue , LDL-Colesterol/sangue , VLDL-Colesterol/sangue , Angiografia Coronária , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Reestenose Coronária/diagnóstico por imagem , Reestenose Coronária/epidemiologia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/instrumentação , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Stents , Fatores de Tempo , Resultado do Tratamento
8.
Lasers Med Sci ; 34(4): 801-805, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30353478

RESUMO

The 532-nm laser has become increasingly popular for the treatment of urologic diseases. However, laser beam will pose significant hazards for the health of surgeons. In order to reduce beam hazards during surgery, we compared the beam hazards of laser fiber with black sleeves to the traditional fiber with transparent sleeves, and the vaporization efficiency. A total of 18 porcine kidney specimens were vaporized in normal saline at a room temperature under 532-nm laser delivered through a 760-µm core diameter side firing fiber. Two groups were divided according to the color of fiber sleeves: the transparent and the black. Each group was then divided into another three subgroups by laser power: the 80 W group, the 120 W group, and the 160 W group. The beam hazard was evaluated by light intensity measured in a sector area at a distance of 0 m, 0.5 m, and 1 m from the irradiation center. The vaporization efficiency was measured by the vaporization groove depth under the working power of 80 W, 120 W, and 160 W with a working distance of 5 mm and irradiation time of 10 s. The light intensity measured in the black fiber sleeve group is significantly lower than that in the transparent one (P < 0.01), regardless of the measuring distance (0 m, 0.5 m, and 1.0 m) and laser power (80 W, 120 W, and 160 W). No statistical difference was found on the vaporization efficiency between the groups protected by fiber sleeves of different colors (transparent/black, p > 0.05). Compared to the traditional transparent fiber sleeves, more beam hazards will be reduced in the operative region with the protection of black fiber sleeves, especially those from the irradiation center. The vaporization efficiency is not affected by the color of fiber sleeves. Such findings may offer a completely new idea for the protection of surgeons in surgeries with 532-nm lasers.


Assuntos
Rim/efeitos da radiação , Lasers , Animais , Rim/anatomia & histologia , Rim/citologia , Terapia a Laser , Masculino , Suínos , Volatilização
9.
J Mol Model ; 24(10): 298, 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30267159

RESUMO

In order to reveal the mechanism of drug action and design of DNA/RNA-targeted drugs containing aromatic rings, the cooperativity effects between the intermolecular π∙∙∙π and H-bonding interactions in curcumin(drug)∙∙∙cytosine(DNA/RNA base)∙∙∙H2O were investigated by the B3LYP-D3 and MP2(full) methods with the 6-311++G(2d,p) basis set. The π∙∙∙π interaction plays an important role in stabilizing the linear ternary complexes with the cooperativity effects, and the cyclic structures suffer the anticooperativity effects. The cooperativity or anticooperativity effects are notable, which could lead to a possible significant change in drug activity. The hydration is essentially the cooperativity or anticooperativity effect. These results were confirmed by the atoms in molecules (AIM), reduced density gradient (RDG), and surface electrostatic potentials analyses. The cyclic complexes are more stable, from which it can be deduced that the drug always links with the DNA/RNA base and H2O by the π∙∙∙π or H-bonding interactions, and only in this way can the drug activity be shown. Therefore, the designed DNA/RNA-targeted drugs should possess a certain number of hydrophilic groups in contact with the DNA/RNA base and H2O to reconcile drug activity by the cooperativity effect between the π∙∙∙π and H-bonding interactions, as is in agreement with many of the drugs in use. Graphical abstract RDG isosurface of ternary complex.


Assuntos
Curcumina/química , Citosina/química , Modelos Moleculares , Água/química , Descoberta de Drogas , Ligação de Hidrogênio
10.
J Geriatr Cardiol ; 15(2): 137-145, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29662507

RESUMO

BACKGROUND: Percutaneous coronary intervention (PCI) had become the major therapeutic procedure for coronary artery disease (CAD), but the high rate of in-stent restenosis (ISR) still remained an unsolved clinical problem in clinical practice. Increasing evidences suggested that diabetes mellitus (DM) was a major risk factor for ISR, but the risk predictors of ISR in CAD patients with DM had not been well characterized. The aim of this study was to investigate the clinical and angiographic characteristic predictors significantly associated with the occurrence of ISR in diabetic patients following coronary stenting with drug-eluting stent (DES). METHODS: A total of 920 patients with diabetes who diagnosed CAD and underwent coronary DES implantation at Beijing Anzhen Hospital in China were consecutively enrolled from January 2012 to December 2012. Of these, 440 patients underwent the second angiography within ≥ 6 months due to the progression of treated target lesions. Finally, 368 of these patients who met the inclusion and exclusion criteria were followed up by angiography after baseline PCI. According to whether ISR was detected at follow-up angiography, patients were divided into the ISR group (n = 74) and the non-ISR group (n = 294). The independent predictors of ISR in patients with DM were explored by multivariate Cox's proportional hazards regression models. RESULTS: A total of 368 patients (260 women and 108 men) with a mean ages of 58.71 ± 10.25 years were finally enrolled in this study. Of these, ISR occurred in 74/368 diabetic patients (20.11%) by follow-up angiography. Univariate analysis showed that most baseline characteristics of the ISR and non-ISR group were similar. Patients in the ISR group had significantly higher serum very low density lipoprotein cholesterol (VLDL-C), triglyceride (TG) and uric acid (UA) levels, more numbers of target vessel lesions, higher prevalence of multi-vessel disease, higher SYNTAX score, higher rate of previous but lower rate of drinking compared with patients in the non-ISR group. The independent predictors of ISR in patients with DM after DES implantation included VLDL-C (HR = 1.85, 95% CI: 1.24-2.77, P = 0.002), UA (per 50 µmol/L increments, HR = 1.19, 95% CI: 1.05-1.34, P = 0.006), SYNTAX score (per 5 increments, HR = 1.34, 95% CI: 1.03-1.74, P = 0.031) and the history of PCI (HR = 3.43, 95% CI: 1.57-7.80, P = 0.003) by the multivariate Cox's proportional hazards regression analysis. CONCLUSIONS: The increased serum VLDL-C and UA level, higher SYNTAX score and the history of previous PCI were independent predictors of ISR in patients with DM after coronary DES implantation. It provided new evidence for physicians to take measures to lower the risk of ISR for the better management of diabetic patients after PCI.

11.
Chin Med J (Engl) ; 130(19): 2326-2332, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28836572

RESUMO

BACKGROUND: High rate of in-stent restenosis (ISR) remained an unsolved clinical problem in clinical practice, especially among patients with diabetes mellitus (DM). Diabetic patients often had hypertriglyceridemia with elevated levels of very low-density lipoprotein cholesterol (VLDL-C). Increasing evidence suggested that VLDL-C was known as a significant risk factor for atherosclerosis and had been recommended as a treatment target by current dyslipidemia guidelines. However, the role of VLDL-C in the occurrence and development of ISR in coronary artery disease (CAD) patients with DM had not been studied. The aim of this study was to evaluate the association between the elevated levels of VLDL-C and the risk of ISR in CAD patients with DM. METHODS: A total of 1390 diabetic patients, who underwent coronary drug-eluting stent (DES) implantation at Beijing Anzhen Hospital and followed up by angiography within 6-24 months, were consecutively enrolled. Patients' demographic and clinical characteristics, including age, gender, CAD risk factors, family history, life style, medical history, and coronary angiographic information, were collected carefully at baseline percutaneous coronary intervention and follow-up angiography. Multivariate Cox's proportional hazards regression modeling using the step-wise method (entry, 0.05; removal, 0.05) was used to determine the independent risk associated with ISR in diabetic patients. RESULTS: Finally, 1206 of patients were included in this study. ISR occurred in 132/1206 diabetic patients (10.9%) by follow-up angiography. Patients with ISR had elevated median serum VLDL-C levels compared with those without ISR (0.65 mmol/L vs. 0.52 mmol/L, P = 0.030). The multivariate regression analysis showed that VLDL-C was significantly associated with the risk of ISR in diabetic CAD patients (hazard ratio [HR] = 1.15, 95% confidence interval [CI]: 1.03-1.29, P = 0.017). The HR for the risk of ISR associated with VLDL-C level ≥0.52 mmol/L was 3.01 (95% CI: 1.24-7.34, P = 0.015). CONCLUSION: The elevated level of serum VLDL-C was a significant and independent risk factor for ISR in diabetic CAD patients after coronary DES implantation.


Assuntos
VLDL-Colesterol/sangue , Doença da Artéria Coronariana/terapia , Diabetes Mellitus/terapia , Stents Farmacológicos , Oclusão de Enxerto Vascular/sangue , Oclusão de Enxerto Vascular/etiologia , Idoso , Doença da Artéria Coronariana/sangue , Diabetes Mellitus/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco
12.
Anal Biochem ; 525: 100-106, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28263739

RESUMO

Microfluidic paper-based analytical devices (µPADs) have a significant potential in developing portable and disposable point-of-care testing (POCT). Herein, a facile, rapid, cost-effective and environment friendly strategy for µPADs fabrication is proposed. Specifically, the substrate paper was hydrophobized by coating with trimethoxysilane (TOS), and then the selected area was hydrophilized by treating with surfactant. The whole fabrication process was implemented within 7 min, with no need for complex pre-treatment, high-temperature and special equipment. As a proof-of-concept application, the as-prepared µPAD was applied to determination of the glucose content in human serum samples. The results agreed well with those obtained by a glucometer. We believe that the µPADs fabrication method proposed here could provide a facile, rapid and low-cost reference for other related studies.


Assuntos
Glicemia/análise , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Papel , Desenho de Equipamento , Humanos , Interações Hidrofóbicas e Hidrofílicas , Sistemas Automatizados de Assistência Junto ao Leito
13.
Chin Med J (Engl) ; 129(12): 1432-8, 2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27270538

RESUMO

BACKGROUND: The European Society of Urogenital Radiology has built the Prostate Imaging Reporting and Data System (PI-RADS) for standardizing the diagnosis of prostate cancer (PCa). This study evaluated the PI-RADS diagnosis method in patients with prostate-specific antigen (PSA) <20 ng/ml. METHODS: A total of 133 patients with PSA <20 ng/ml were prospectively recruited. T2-weighted (T2WI) and diffusion-weighted (DWI) magnetic resonance images of the prostate were acquired before a 12-core transrectal prostate biopsy. Each patient's peripheral zone was divided into six regions on the images; each region corresponded to two of the 12 biopsy cores. T2WI, DWI, and T2WI + DWI scores were computed according to PI-RADS. The diagnostic accuracy of the PI-RADS score was evaluated using histopathology of prostate biopsies as the reference standard. RESULTS: PCa was histologically diagnosed in 169 (21.2%) regions. Increased PI-RADS score correlated positively with increased cancer detection rate. The cancer detection rate for scores 1 to 5 was 2.8%, 15.0%, 34.6%, 52.6%, and 88.9%, respectively, using T2WI and 12.0%, 20.2%, 48.0%, 85.7%, and 93.3%, respectively, using DWI. For T2WI + DWI, the cancer detection rate was 1.5% (score 2), 13.5% (scores 3-4), 41.3% (scores 5-6), 75.9% (scores 7-8), and 92.3% (scores 9-10). The area under the curve for cancer detection was 0.700 (T2WI), 0.735 (DWI) and 0.749 (T2WI + DWI). The sensitivity and specificity were 53.8% and 89.2%, respectively, when using scores 5-6 as the cutoff value for T2WI + DWI. CONCLUSIONS: The PI-RADS score correlates with the PCa detection rate in patients with PSA <20 ng/ml. The summed score of T2WI + DWI has the highest accuracy in detection of PCa. However, the sensitivity should be further improved.


Assuntos
Imageamento por Ressonância Magnética/métodos , Antígeno Prostático Específico/sangue , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias da Próstata/sangue
14.
Neural Regen Res ; 10(6): 958-64, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26199614

RESUMO

Hydrogen can relieve tissue-damaging oxidative stress, inflammation and apoptosis. Injection of hydrogen-rich saline is an effective method for transporting molecular hydrogen. We hypothesized that hydrogen-rich saline would promote the repair of spinal cord injury induced by Allen's method in rats. At 0.5, 1, 2, 4, 8, 12 and 24 hours after injury, then once daily for 2 weeks, 0.25 mL/kg hydrogen-rich saline was infused into the subarachnoid space through a catheter. Results at 24 hours, 48 hours, 1 week and 2 weeks after injury showed that hydrogen-rich saline markedly reduced cell death, inflammatory cell infiltration, serum malondialdehyde content, and caspase-3 immunoreactivity, elevated serum superoxide dismutase activity and calcitonin gene-related peptide immunoreactivity, and improved motor function in the hindlimb. The present study confirms that hydrogen-rich saline injected within 2 weeks of injury effectively contributes to the repair of spinal cord injury in the acute stage.

15.
Huan Jing Ke Xue ; 36(2): 604-11, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-26031089

RESUMO

Effects of dissolved oxygen (DO) on the biodegradation of organic pollutants were investigated using A/O reactors for the treatment of actual petrochemical wastewater. Two A/O reactors, DO were controlled at 2-3 mg x L(-1) in the oxic parts of reactor A and 5-6 mg x L(-1) of reactor B, were operated in parallel for comparison. The nearly a half of year operation results showed that the effluent COD in reactor A (72.5 ± 14.8 mg x L(-1)) was slightly higher than that in reactor B (68.7 ± 14.6 mg x L(-1)) at a HRT of 20 h. The average COD removal efficiencies were 67.0% and 68.8%, respectively. The effluent ammonium concentration was maintained at 0.8 mg x L(-1) and approximately 95% of ammonium removal was achieved. The effluent BOD, concentration was lower than 5 mg x L(-1). This indicated that the organic pollutants could be degraded thoroughly by the A/O processes, which were affected slightly by DO. Results of 454 pyrosequencing analysis of the sludge in oxic parts showed that at the phylum levels, sequences belonged to Proteobacteria, Planctomycetes and Bacteroidetes were abundant with 58.7% and 59.2%, 14.7% and 12.7%, 10.8% and 12.4% of total bacterial sequences in reactor A and B, respectively. Ammonium oxidation bacteria Nitrosomonas, nitrite oxidizing bacteria Nitrospira and obligate aerobic bacteria were highly enriched in reactor B with high DO levels, while the anaerobic denitrifiers Azospira and Acidovora were highly enriched in reactor A with low DO levels. The identified bacteria belonged to genera Novosphingobium, Comamonas, Sphingobium and Altererythrobacter were reported to degrade PAHs, chloronitrobenzene, pesticides and petroleum, which contributed to the degradation of petrochemical wastewater.


Assuntos
Bactérias Aeróbias/metabolismo , Reatores Biológicos/microbiologia , Oxigênio/química , Águas Residuárias/química , Purificação da Água/métodos , Biodegradação Ambiental , Petróleo , Esgotos , Poluentes Químicos da Água/química
16.
J Nanosci Nanotechnol ; 14(9): 6941-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25924353

RESUMO

Pentachlorophenol (PCP), as an important contaminant which was toxic and intractable, has received extensive attention. In this paper, the temperature effect during the transformation of PCP using nanoscale Fe(0) particles was studied, and the transformation processes of PCP and iron particles was explained. The results revealed that the removal processes of PCP followed pseudo first-order kinetics. The scale of dechlorination to the transformation of PCP increased with the increase of temperature, though the transformation rate decreased after reacting for 2 h under the experimental condition. However, the initial apparent transformation rate constants were calculated to be 0.312-0.536 h(-1) at the temperature of 20-50 degrees C, which showed an increase of transformation rate along with the increase of temperature. And the surface-area-normalized rate constants were calculated to be 9.50 x 10-3-1.63 x 10-2 L . h-1 . m-2. The experimental activation energy was calculated to be 15.0 kJ x mol(-1) from these rate constants using Arrhenius equation. A phenomenon observed at 50 degrees C indicated that more than one chlorine atom was removed from PCP and suggested ß-elimination might be the major pathway for transformation. Sorption experiments showed that the sorption process on the surface of particles could be ignored in the kinetics and thermodynamics models. The changes of morphologies of nanoparticles before and after reaction indicated the transformation process of iron particles, and could be used to explain the changes of activity of nanoparticles. Magnetite (Fe3O4) and/or maghemite (Fe2O3) and lepidocrocite (γ-FeOOH) were corrosion products of iron. And along with the increase of temperature, the increased intensity of XRD peaks revealed the related a better crystallizing.


Assuntos
Nanopartículas de Magnetita/química , Pentaclorofenol/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Cinética , Nanotecnologia , Pentaclorofenol/química , Termodinâmica , Poluentes Químicos da Água/química , Purificação da Água
17.
Huan Jing Ke Xue ; 34(4): 1411-5, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23798122

RESUMO

Because chlorine is an electron withdrawing group, the highly chlorinated phenols may react quickly with hydrated electrons rather than with hydroxyl radicals. The process of reactions of four chlorophenols (4-CP, 2-CP, 2,4-DCP, 2,4,6-TCP) with e(aq)(-) was investigated in aqueous solutions by detecting the concentration of CPs, Cl- and intermediates. In the e(aq)(-) reductive system, the experimental results showed that the order of four kinds of chlorophenol degradation and dechlorination was 2,4,6-TCP > 2,4-DCP > 2-CP > 4-CP. The greater the chlorine content was the higher reactivity of hydrated electrons towards chlorophenols was. Furthermore, hydrated electrons may preferentially attack the ortho-position of chlorine atom rather than the para-position of chlorine atom. Phenol and Cl- were detected as the final product of the reductive reaction. Additionally, processes of degradation and dechlorination of CPs were observed as the pseudo-first-order kinetics. The reaction constant of degradation of 4-CP, 2-CP, 2,4-DCP and 2,4,6-TCP were 0.154, 0.253, 0.750 and 1.188 kGy(-1), respectively. Meanwhile, the dechlorination of 4-CP, 2-CP, 2,4-DCP and 2,4,6-TCP were 0.137, 0.219, 0.251 and 0.306 kGy(-1), respectively.


Assuntos
Clorofenóis/isolamento & purificação , Raios gama , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Clorofenóis/efeitos da radiação , Radioisótopos de Cobalto , Oxirredução , Poluentes Químicos da Água/efeitos da radiação
18.
J Mol Model ; 19(6): 2499-507, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23446440

RESUMO

A comparative theoretical investigation into the change in strength of the trigger-bond upon formation of the Na(+), Mg(2+) and HF complexes involving the nitro group of RNO2 (R = -CH3, -NH2, -OCH3) or the C = C bond of (E)-O2N-CH = CH-NO2 was carried out using the B3LYP and MP2(full) methods with the 6-311++G**, 6-311++G(2df,2p) and aug-cc-pVTZ basis sets. Except for the Mg(2+)⋯π system with (E)-O2N-CH = CH-NO2 (i.e., C2H2N2O4⋯Mg(2+)), the strength of the trigger-bond X-NO2 (X = C, N or O) was enhanced upon complex formation. Furthermore, the increment of bond dissociation energy of the X-NO2 bond in the Na(+) complex was far greater than that in the corresponding HF system. Thus, the explosive sensitivity in the former might be lower than that in the latter. For C2H2N2O4⋯Mg(2+), the explosive sensitivity might also be reduced. Therefore, it is possible that introducing cations into the structure of explosives might be more efficacious at reducing explosive sensitivity than the formation of an intermolecular hydrogen-bonded complex. AIM, NBO and electron density shifts analyses showed that the electron density shifted toward the X-NO2 bond upon complex formation, leading to a strengthened X-NO2 bond and possibly reduced explosive sensitivity.

19.
Can J Cardiol ; 29(9): 1084-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23414904

RESUMO

BACKGROUND: Myocardial necrosis occurs frequently in elective percutaneous coronary intervention (PCI) and is associated with subsequent major adverse cardiovascular events (MACEs). This study assessed the protective effect of remote ischemic preconditioning (RIPC) in patients undergoing successful drug-eluting stent implantation with normal baseline troponin values. METHODS: We analyzed 205 participants with normal baseline troponin values undergoing successful coronary stent implantation. Subjects were randomized to 2 groups: The RIPC group (n = 101), whose members received RIPC (created by three 5-minute inflations of a pneumatic medical tourniquet cuff to 200 mm Hg around the upper arm, interspersed with 5-minute intervals of reperfusion) < 2 hours before the PCI procedure, and the control group (n = 104). RESULTS: The primary outcomes were high sensitive cardiac troponin I (hscTnI) levels and incidence of myocardial infarction (MI 4a, defined as hscTnI > 0.20 ng/mL) at 16 hours after the PCI procedure. The median hscTnI at 16 hours after PCI was lower in the RIPC group compared with the unpreconditioned, control group (0.11 vs 0.21 ng/mL; P < 0.01). The incidence of MI 4a was lower in the RIPC group compared with the control group (39% vs 54%, P < 0.05). Index of renal function showed no difference between the 2 groups at 16 hours after PCI (P > 0.05). CONCLUSION: RIPC reduced post-PCI TnI release and incidence of MI 4a in patients undergoing elective coronary stent implantation.


Assuntos
Doença da Artéria Coronariana/cirurgia , Stents Farmacológicos , Precondicionamento Isquêmico Miocárdico/métodos , Infarto do Miocárdio/prevenção & controle , Intervenção Coronária Percutânea , Troponina I/sangue , Idoso , Estudos de Casos e Controles , Doença da Artéria Coronariana/sangue , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia
20.
J Mol Model ; 19(1): 163-71, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22949063

RESUMO

The structure and thermodynamic properties of the 2, 4-dinitroimidazole complex with methanol were investigated using the B3LYP and MP2(full) methods with the 6-31++G(2d,p) and 6-311++G(3df,2p) basis sets. Four types of hydrogen bonds [N-H⋯O, C-H⋯O, O-H⋯O (nitro oxygen) and O-H⋯π] were found. The hydrogen-bonded complex having the highest binding energy had a N-H⋯O hydrogen bond. Analyses of natural bond orbital (NBO) and atoms-in-molecules (AIM) revealed the nature of the intermolecular hydrogen-binding interaction. The changes in thermodynamic properties from monomers to complexes with temperatures ranging from 200.0 to 800.0 K were investigated using the statistical thermodynamic method. Hydrogen-bonded complexes of 2,4-dinitroimidazole with methanol are fostered by low temperatures.

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