Modification of regenerated cellulose ultrafiltration membranes with multi-walled carbon nanotubes for enhanced antifouling ability: Field test and mechanism study.

Although ultrafiltration (UF) has been extensively employed for drinking water purification, it is crucial to further develop novel membrane materials to improve the antifouling capacity and satisfy the practical usage. Multi-walled carbon nanotubes (MWCNTs) have characteristics that could potentially improve the membrane antifouling performance. Therefore, in this study, modified cellulose UF membranes were prepared using MWCNTs of various outer diameters ranging from 10 to 20 nm to 40-60 nm. The antifouling properties of the modified membrane and natural organic matter (NOM) removal mechanism were investigated while treating water from a local drinking water source river. Overall, the antifouling ability increased by more than one-fold when the nascent cellulose membrane was coated with MWCNTs (outer diameter of 40-60 nm) at a loading of 17.4 g/m2. The molecular weight distribution profiles of the NOM in the raw water and permeates suggest the superior performance of the modified membranes in removing two major NOM fractions with molecular weights ranging from approximately 5 k-30 k and 500 k-1000 k. Based on its hydrophobicity, the NOM of the raw water was fractionated into the strong hydrophobic (SHPO), the weak hydrophobic, the strong hydrophilic and the moderately hydrophilic (MHPI) fractions. The WHPO fraction caused the highest fouling compared with the other fractions under consistent experimental conditions. Meanwhile, the modified membranes showed a preference for removing the MHPI and SHPO fractions. These results imply that MWCNTs can be employed to improve the antifouling property of cellulose UF membranes and have the potential to selectively remove moderately hydrophilic contaminants from water.

Distribution and fate modeling of 4-nonylphenol, 4-t-octylphenol, and bisphenol A in the Yong River of China.

In this study, the concentrations of 4-nonylphenol (4-NP), 4-tert-octylphenol (4-t-OP), and bisphenol A (BPA) in the water column of the Yong River were investigated and found to be in the range of 140-3948, 6-828, and 15-1415 ng L-1, respectively. A fate and transport model coupled with the Water Quality Analysis Simulation Program (WASP) was developed. After model calibration and validation, the distributions of 4-NP, 4-t-OP, and BPA in the Yong River were modeled for the duration of 2015. The total contaminant loads from the upstream boundary, four tributaries and two wastewater treatment plants were determined to be 2318 kg yr-1 for 4-NP, 506 kg yr-1 for 4-t-OP, and 970 kg yr-1 for BPA. Both measured and modeled results reported higher concentrations of the selected contaminants near river confluences and at the outfalls of the wastewater treatment plants. Peak concentrations were found to always appear in months with relatively reduced precipitation. The influences of adsorption and degradation on the dissolved concentrations of the selected chemicals were also modeled. The combined effects of adsorption and degradation were found to reduce dissolved concentrations of 4-NP, 4-t-OP, and BPA by 17.9%, 30.7%, and 12.1%, respectively. Adsorption was shown to reduce 4-NP concentrations in the Yong River more than degradation. Conversely, adsorption and degradation caused almost equal reductions in the dissolved concentrations of 4-t-OP and degradation caused larger decreases than adsorption in the dissolved concentrations of BPA.

The regulative function of mitochondria in innate immune response to chronic HBV infection / 中华检验医学杂志

Innate immunity initially resists the infection of pathogenic microorganism in host immune response.Recent researches confirmed that mitochondria participated in a wide range of innate immune pathways,mainly including contributing to innate immune activation,regulating antiviral signaling pathways and antibacterial immunity.Therefore,further studies on the relationship among mitochondria,hepatitis B virus(HBV)infection and innate immune response might contribute to elucidate the mechanism of chronic HBV infection and explore the mechanism of host immune to clear HBV.Here,mitochondria playing a vital role in regulations of innate immune response,HBV infection tending to chronicity by suppressing innate immune response and chronic HBV infection by regulating the innate immune response through injuring mitochondria,were reviewed.

Oxidation of SO2 to SO3 by Cerium Oxide Cluster Cations Ce2O4(+) and Ce3O6(.).

Cerium oxide cationic clusters (CeO2)1-3(+) were generated through laser ablation and then reacted with sulfur dioxide (SO2) at ambient conditions in an ion trap reactor and those reactions were studied and characterized by combining the art of time-of-flight mass spectrometry (TOF-MS) with density functional theory (DFT) calculations. Molecule association and oxygen atom transfer (OAT) were observed for the CeO2(+) and (CeO2)2,3(+) reaction systems, respectively. The mechanistic analysis indicates that the weak Ce-O bond strength associated with the oxygen release capacity of cerium oxide clusters is considered as the key factor to achieve the oxidation of SO2. To our best knowledge, this research should be the first example to identify the OAT reactivity of metal oxide cluster ions toward sulfur dioxide under thermal collision conditions, and a fundamental understanding of the elementary oxidation of SO2 to SO3 is provided.

Generation of Hydroxyl Radicals in the Reaction of Dihydrogen with AuNbO4+ Cluster Cations.

A molecular-level insight into the nature of reactive oxygen species involved in dihydrogen (H2 ) dissociation is of great importance to understand gold catalysis. In this study, laser ablation generated and mass-selected AuNbO4+ oxide cluster cations could dissociate H2 in an ion-trap reactor. The reaction has been characterized by time-of-flight mass spectrometric experiments and density functional calculations. The lowest energy isomer of AuNbO4+ contains two lattice oxygen (O2- ) and one superoxide (O2.- ) species. The gold atom anchors the H2 molecule in the first step and then delivers one hydrogen atom to the O2- ion in H2 dissociation. At the same time, O2.- is reduced into a peroxide unit that can accept the second hydrogen atom of H2 with the generation of a hydroxyl radical as the main product. In this study, the important roles of the O2.- unit in the dissociation of H2 have been identified.

Thermal conversion of methane to formaldehyde promoted by gold in AuNbO3(+) cluster cations.

In addition to generation of a methyl radical, formation of a formaldehyde molecule was observed in the thermal reaction of methane with AuNbO3(+) heteronuclear oxide cluster cations. The clusters were prepared by laser ablation and mass-selected to react with CH4 in an ion-trap reactor under thermal collision conditions. The reaction was studied by mass spectrometry and DFT calculations. The latter indicated that the gold atom promotes formaldehyde formation through transformation of an Au-O bond into an Au-Nb bond during the reaction.

Clinical distribution and drug resistance of 179 isolates of Streptococcus agalactia / 国际检验医学杂志

Objective To investigated the clinical distributions and antimicrobial susceptibility of Streptococcus agalactia strains isolated from the patients .Methods The identification and susceptibility of the strains were mainly measured by automatic VITEK‐Ⅱ system ,the K‐B disc diffusion tests were used for the resistance test of erythromycin ,meropenem ,and D‐test .Results The iso‐lates were mainly from urine (63 .1% ) ,genital tract(7 .8% ) and wound secretion(6 .7% ) .They were obtained from patients in dif‐ferent situations ,including 110 patients who were older than 50 years old (61 .5% ) ,113 female patients (63 .1% ) ,12 gravidas (6 .7% ) ,3 vertical transmitted newborns(1 .7% ) ,and 82 patients with cancer ,undergoing chemo radiotherapy ,with diabetes ,tuber‐culosis or after operations(45 .8% ) .The resistant rates of the isolated Streptococcus agalactia to erythromycin and clindamycin were 42 .9% -93 .3% and 41 .9% -80 .0% respectively .The positive rate of D‐test was 4 .1% .The strains were highly resistant to tet‐racycline(>80% ) ,while the resistance to penicillin was below 10% except in 2008 .All isolates were susceptible to vancomycin and meropenem .Only one strain was resistant to Quinupristin‐dalfopristin .Conclusion Streptococcus agalactia infection in adults most‐ly cause genitourinary tract ,skin and soft tissue infections .There were more females than males with Streptococcus agalactia infec‐tion .Penicillin andβ‐lactams are still the first choice for the treatment .Erythromycin ,clindamycin and tetracycline should be used with caution under the guidance of laboratory susceptibility test results .

[Construction and expression of human EpCAM eukaryotic expression vectors and identification of their products].

AIM: To construct EpCAM eukaryotic expression vectors pIg-EpCAM and pEGFP-EpCAM and to express them in COS7 cells. METHODS: EpCAM cDNA was amplified by PCR and then inserted into the pIg and pEGFP vectors respectively to construct recombinant vectors pIg-EpCAM and pEGFP-EpCAM. The two recombinant vectors were transfected into COS7 cells under the mediation of liposome. The expressed EpCAM-Ig fusion protein was detected by Western blot. The expression of EpCAM-GFP fusion protein was observed under fluorescence microscope. RESULTS: DNA sequencing demonstrated that EpCAM was correctly cloned into the two vectors. The culture supernatant of the pIg-EpCAM-transfected COS7 cells could bind effectively to mAb against human IgG Fc. Green fluorescence distributed evenly in the cytoplasm and nuclei of pEGFP-transfected COS7 cells, whereas in pEGFP-EpCAM transfected COS7 cells, green fluorescence distributed mainly on the surface of the cells. CONCLUSION: Two EpCAM eukaryotic expression vectors have been constructed and expressed successfully, which lays the foundation for functional research of EpCAM and for preparation of mAb to EpCAM.

[Prevalence of dental anxiety in 144 patients with cardiovascular diseases before tooth extraction].

OBJECTIVE: To determine the prevalence of dental anxiety (DA) in patients with cardiovascular diseases before tooth extraction so as to provide psychotherapy. METHODS: 144 patients with cardiovascular diseases were asked to complete a questionnaire modified from Corah Dental Anxiety Scale (DAS) while awaiting for tooth extraction. RESULTS: The incidence rate of DA in these patients was 7.6%. Anxiety level on anesthesia procedure was the highest. DAS score was higher among patients with the following factors: inactive perception, female, below 60 years old, experiences of painful tooth extraction, a documented history of single cardiovascular disease, under ECG monitoring for the first time and complicated tooth extraction. CONCLUSION: DA existed in patients with cardiovascular diseases before tooth extraction and was related to many factors. Medical staff should take necessary measures to provide them with psychotherapy and nursing guidance before tooth extraction.

[Study on cellular and serum concentration of calcium and magnesium in peripheral blood cells of cirrhosis].

OBJECTIVES: To study on the changes of intracellular calcium and magnesium in cirrhosis and its clinical significance. METHODS: The calcium and magnesium were determined in serum (SCa, SMg), platelets (PCa, PMg), mononuclear cells (MNCCa, MNCMg), polymorphonuclear cells (PMNCa, PMNMg) and erythrocytes (RCa, RMg) of 50 patients with uncompensative cirrhosis (group A) and of 35 patients with compensative cirrhosis (group B). 35 health persons were the control group. RESULTS: The SCa and SMg of group A were lower significantly than those of both group B and control group. The MNCCa, PMNCa, RCa, PMg, MNCMg, PMNMg, RMg of group A [(4.76+/-1.91) micromol/10(9), (7.56+/-2.88) micromol/10(9), (0.66+/-0.13) mmol/L, (5.53+/-2.25) micromol/10(11), (6.64+/-3.53) micromol/10(9), (10.12+/-4.32) micromol/10(9), (2.02+/-0.76) mmol/L] and those of group B [(5.34+/-2.41) micromol/10(9), (8.32+/-2.34) micromol/10(9), (0.67+/-0.11) mmol/L, (5.55+/-2.67) micromol/10(11), (6.56+/-3.44) micromol/10(9), (10.95+/-4.45) micromol/10(9), (2.21+/-0.74) mmol/L] were lower significantly than those of control group [(6.86+/-2.02) micromol/10(9), (9.89+/-3.23) micromol/10(9), (0.72+/-0.10) mmol/L, (7.43+/-2.78) micromol/10(11), (8.68+/-4.1) micromol/10(9), (13.96+/-5.76) micromol/10(9), (2.74+/-0.92) mmol/L]; t (group A vs. control group)=4.88, 3.48, 2.31, 3.45, 2.46, 3.52, 4.00, 0.01, 0.01, 0.05, 0.01, 0.02, 0.01, 0.01; t (group B vs. control group)=2.87, 2.34, 2.00, 2.89, 2.33, 2.45, 2.65, 0.01, 0.05, 0.05, 0.01, 0.05, 0.02, 0.02. The PCa of the patients with hepatic encephalopathy was higher, the SMg, PMg, MNCMg, PMNMg and RMg were lower than those of the patients without hepatic encephalopathy significantly. The SCa, SMg, PMg, MNCMg, PMNMg and RMg of the patients in Child stage C were lower significantly than those of the patients in Child stage B. There were no significant differences of PCa, MNCCa, PMNCa and RCa between Child stage C and Child stage B. There were no significant differences of SCa, MNCCa, PMNCa and RCa between the patients with and without hepatic encephalopathy. The ratios of PCa/SCa, MNCCa/SCa and PMNCa/SCa of the patients with decreased SMg were lower than those of control group. The SMg, MNCMg, PMNMg and RMg were correlated directly with the level of serum albumin. CONCLUSION: There are calcium and magnesium deficiencies in the patients with uncompensative cirrhosis and compensative cirrhosis, this deficiency aggravates with the severity of the disease. There is relative increase of intracellular calcium. The magnesium deficiency may be one of the reasons for both hepatic encephalopathy and relative increase of intracellular calcium.

Study on cellular and serum concentration of calcium and magnesium in peripheral blood cells of cirrhosis / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To study on the changes of intracellular calcium and magnesium in cirrhosis and its clinical significance.</p><p><b>METHODS</b>The calcium and magnesium were determined in serum (SCa, SMg), platelets (PCa, PMg), mononuclear cells (MNCCa, MNCMg), polymorphonuclear cells (PMNCa, PMNMg) and erythrocytes (RCa, RMg) of 50 patients with uncompensative cirrhosis (group A) and of 35 patients with compensative cirrhosis (group B). 35 health persons were the control group.</p><p><b>RESULTS</b>The SCa and SMg of group A were lower significantly than those of both group B and control group. The MNCCa, PMNCa, RCa, PMg, MNCMg, PMNMg, RMg of group A [(4.76+/-1.91) micromol/10(9), (7.56+/-2.88) micromol/10(9), (0.66+/-0.13) mmol/L, (5.53+/-2.25) micromol/10(11), (6.64+/-3.53) micromol/10(9), (10.12+/-4.32) micromol/10(9), (2.02+/-0.76) mmol/L] and those of group B [(5.34+/-2.41) micromol/10(9), (8.32+/-2.34) micromol/10(9), (0.67+/-0.11) mmol/L, (5.55+/-2.67) micromol/10(11), (6.56+/-3.44) micromol/10(9), (10.95+/-4.45) micromol/10(9), (2.21+/-0.74) mmol/L] were lower significantly than those of control group [(6.86+/-2.02) micromol/10(9), (9.89+/-3.23) micromol/10(9), (0.72+/-0.10) mmol/L, (7.43+/-2.78) micromol/10(11), (8.68+/-4.1) micromol/10(9), (13.96+/-5.76) micromol/10(9), (2.74+/-0.92) mmol/L]; t (group A vs. control group)=4.88, 3.48, 2.31, 3.45, 2.46, 3.52, 4.00, 0.01, 0.01, 0.05, 0.01, 0.02, 0.01, 0.01; t (group B vs. control group)=2.87, 2.34, 2.00, 2.89, 2.33, 2.45, 2.65, 0.01, 0.05, 0.05, 0.01, 0.05, 0.02, 0.02. The PCa of the patients with hepatic encephalopathy was higher, the SMg, PMg, MNCMg, PMNMg and RMg were lower than those of the patients without hepatic encephalopathy significantly. The SCa, SMg, PMg, MNCMg, PMNMg and RMg of the patients in Child stage C were lower significantly than those of the patients in Child stage B. There were no significant differences of PCa, MNCCa, PMNCa and RCa between Child stage C and Child stage B. There were no significant differences of SCa, MNCCa, PMNCa and RCa between the patients with and without hepatic encephalopathy. The ratios of PCa/SCa, MNCCa/SCa and PMNCa/SCa of the patients with decreased SMg were lower than those of control group. The SMg, MNCMg, PMNMg and RMg were correlated directly with the level of serum albumin.</p><p><b>CONCLUSION</b>There are calcium and magnesium deficiencies in the patients with uncompensative cirrhosis and compensative cirrhosis, this deficiency aggravates with the severity of the disease. There is relative increase of intracellular calcium. The magnesium deficiency may be one of the reasons for both hepatic encephalopathy and relative increase of intracellular calcium.</p>

Prevalence of dental anxiety in 144 patients with cardiovascular diseases before tooth extraction / 中华流行病学杂志

<p><b>OBJECTIVE</b>To determine the prevalence of dental anxiety (DA) in patients with cardiovascular diseases before tooth extraction so as to provide psychotherapy.</p><p><b>METHODS</b>144 patients with cardiovascular diseases were asked to complete a questionnaire modified from Corah Dental Anxiety Scale (DAS) while awaiting for tooth extraction.</p><p><b>RESULTS</b>The incidence rate of DA in these patients was 7.6%. Anxiety level on anesthesia procedure was the highest. DAS score was higher among patients with the following factors: inactive perception, female, below 60 years old, experiences of painful tooth extraction, a documented history of single cardiovascular disease, under ECG monitoring for the first time and complicated tooth extraction.</p><p><b>CONCLUSION</b>DA existed in patients with cardiovascular diseases before tooth extraction and was related to many factors. Medical staff should take necessary measures to provide them with psychotherapy and nursing guidance before tooth extraction.</p>

[Comparative studies on the resistance of hepatitis B by Syringa extract, IFN and ganyanling in HepG2.2.15 cells].

AIM: To explore the effects of Syringa extract, IFN and ganyanling on the the survival rate of HepG2.2.15 cells and the secretion of HBsAg and HBeAg by HepG2.2.15 cells. METHODS: (3)H-TdR incorporation and ELISA were used to detect respectively the survival rate of HepG2.2.15 cells and levels of HBsAg and HBeAg in culture supernatant of HepG2.2.15 cells after stimulation with 3 drugs. RESULTS: (1)All of the three drugs decreased the survival rate of HepG2.2.15 cells to the various extent with the increase of doses. The effect of the Syringa extract was between those of IFN and ganyanling. (2)All of the three drugs might suppress the secration of HBsAg and HbeAg by HepG2.2.15 cells in dose-dependent manner, while the the effect of the syringa extract was between those of IFN and ganyanling. CONCLUSION: The Syringa extract is an effective and low toxic anti-hepatitis B drug.

[A histologic observation of bone formation induced by subperiosteal implantation of resorbable porous block beta-tricalcium phosphate on calvarial surface in rabbits].

OBJECTIVE: By the histologic observation of samples, understanding the osteoconductive histologic behaviour and resorbable mechanism of beta-tricalcium phosphate (beta-TCP). METHODS: Porous block beta-TCP samples were implanted into calvarial surface. Tissue slices dyed with methods of HE and Masson's were observed by microscope and compared with hydroxyapatite(HA). RESULTS: Beta-TCP had the osteoconductivity,as well as HA, plentiful new bone penetrated into materials from the calvarial surface. There was no new bone under the periost obviously. A large number of rhagiorine cells swallowing beta-TCP had been observed. CONCLUSION: Beta-TCP has osteoconductivity, can be used as a substitution for atrophic alveolar ridge augmentation. The function of rhagiorine cell swallowing beta-TCP is the essential resorbable mechanism of beta-TCP.