Human respiratory system is harbored by a vast array of transient and normal microbial flora.A number of pathogenic viruses were diagnosed from samples in different occasions from mild to severe infections of respirat...Human respiratory system is harbored by a vast array of transient and normal microbial flora.A number of pathogenic viruses were diagnosed from samples in different occasions from mild to severe infections of respiratory tract.Molecular methods were developed for detection of these viruses during last two decades.Nucleic acid amplification methods were introduced for rapid and accurate diagnosis of pathogenic viruses.Multiplex detection systems were employed to identify a panel of pathogenic viruses,which requires specialized kits and instruments in some cases.This review summarizes different types of molecular approaches which were developed with time and applied for the detection of pathogenic viruses associated with infections of the respiratory system.展开更多
Sexually transmitted infections (STIs) represent a public health problem due to their high prevalence worldwide and the emergence of multidrug resistance of responsible microorganisms. Medical laboratory diagnosis of ...Sexually transmitted infections (STIs) represent a public health problem due to their high prevalence worldwide and the emergence of multidrug resistance of responsible microorganisms. Medical laboratory diagnosis of sexually transmitted genital infections by traditional methods as culture remains extremely delicate, difficult or impossible (to find extremely fragile organisms that can be cultured). Thus, molecular techniques constitute an alternative to improve accurate diagnostic, personalized patient treatment, and public health. A total of 83 clinical samples including urethral discharge and urine samples from individual patients with symptoms of urethritis received were analyzed using traditional methods and a commercial real-time PCR (qPCR) method. Out of 83 urethritis patients, n = 55 (66.26%) were positive for at least one of the STI pathogens detected by qPCR. qPCR assay was more sensitive (50/83, positive cases) compared to culture (15/83, positive cases) and light microscopy (28/83, positive cases). The most prevalent NTD pathogen in the suspected patients was N. gonorrhoeae with 60.24% (50/83) based on real-time PCR diagnosis. Among the positive cases of STI pathogens, Neisseria gonorrhoeae had the highest frequency 49/55 (89.01%) followed by low frequencies of Trichomonas vaginalis 4/55 (7.27%) and Chlamydia trachomatis 1/55 (1.82%). This highlights the high prevalence of N. gonorrhoeae infection in male urethritis patients and a very important misdiagnosis using traditional routine methods in Burkina Faso by medical laboratories. Thus, this situation may negatively impact patients’ personalized treatment and care and public health with the possible rapid emergence of multidrug-resistant strains. This study also highlights the urgent need to optimize culture for the diagnosis of NTD pathogens in Burkina Faso and the usefulness and the need for the introduction of molecular diagnostic methods in routine diagnosis for the detection of NTD pathogens in the medical laboratories in Burkina Faso.展开更多
The fly ash from waste incineration poses a serious threat to human health due to its high content of dioxins.Hydrothermal treatment is an efficient and clean method on the decomposition and detoxifying of fly ash.To ...The fly ash from waste incineration poses a serious threat to human health due to its high content of dioxins.Hydrothermal treatment is an efficient and clean method on the decomposition and detoxifying of fly ash.To study the degradation mechanism of dioxins,this paper uses molecular dynamics(MD)to simulate the hydrothermal reaction process of polychlorinated dibenzo-p-dioxins(PCDDs)under different conditions,and the degradation mechanism of PCDDs is obtained.The results show that the degradation of PCDDs includes two pathways:the first pathway is the substitution of Cl groups by hydroxyl groups to form low-chlorine substitution products through direct hydrogenation,and the second pathway is the formation of non-toxic benzene ring structures accompanied by the cleavage of C—O bonds.The two degradation pathways of PCDDs well explain the changes in toxicity before and after the hydrothermal treatment of fly ash,which is consistent with experimental results.This study provides theoretical guidance for the harmless treatment process of fly ash via hydrothermal method.展开更多
AIM To compare(1) demographics in urea breath test(UBT) vs endoscopy patients; and(2) the molecular detection of antibiotic resistance in stool vs biopsy samples.METHODS Six hundred and sixteen adult patients undergoi...AIM To compare(1) demographics in urea breath test(UBT) vs endoscopy patients; and(2) the molecular detection of antibiotic resistance in stool vs biopsy samples.METHODS Six hundred and sixteen adult patients undergoing endoscopy or a UBT were prospectively recruited to the study. The Geno Type Helico DR assay was used to detect Helicobacter pylori(H. pylori) and antibiotic resistance using biopsy and/or stool samples from CLOpositive endoscopy patients and stool samples from UBT-positive patients. RESULTS Infection rates were significantly higher in patients referred for a UBT than endoscopy(overall rates: 33% vs 19%; treatment-na?ve patients: 33% vs 14.7%, respectively). H. pylori-infected UBT patients were younger than H. pylori-infected endoscopy patients(41.4 vs 48.4 years, respectively, P < 0.005), with a higher percentage of H. pylori-infected males in the endoscopy-compared to the UBT-cohort(52.6% vs 33.3%, P = 0.03). The Geno Type Helico DR assay was more accurate at detecting H. pylori infection using biopsy samples than stool samples [98.2%(n = 54/55) vs 80.3%(n =53/66), P < 0.005]. Subset analysis using stool and biopsy samples from CLO-positive endoscopy patients revealed a higher detection rate ofresistance-associated mutations using stool samples compared to biopsies. The concordance rates between stool and biopsy samples for the detection of H. pylori DNA, clarithromycin and fluoroquinolone resistance were just 85%, 53% and 35%, respectively. CONCLUSION Differences between endoscopy and UBT patients provide a rationale for non-invasive detection of H. pylori antibiotic resistance. However, the Geno Type Helico DR assay is an unsuitable approach.展开更多
To rapidly obtain high-quality genomic DNA from Chenopodium quinoa Willd, the genomic DAN in different tissues （leaves, stems and roots） of Chenopodi- um quinoa Willd was extracted by modified CTAB method, SDS metho...To rapidly obtain high-quality genomic DNA from Chenopodium quinoa Willd, the genomic DAN in different tissues （leaves, stems and roots） of Chenopodi- um quinoa Willd was extracted by modified CTAB method, SDS method and high- salt Iow-pH method, respectively. The quality and yield of extracted DNA was deter- mined using agarose gel electrophoresis and UV spectrophotometry. At the same time, the PCR-SSR and SSCP molecular detection was also performed. The results showed that the gel test strips, without obvious decomposition, of all the extraction methods were relatively obvious; the genomic DNA yield extracted by modified CTAB method was highest, followed by that by SDS method, and the genomic DNA extracted by high-salt Iow-pH method was lowest： the genomic DNA yields extracted by different methods from Chenopodium quinoa Wiltd leaves were all high- er than those from roots and stems; the quality of Chenopodium quinoa Willd ge- nomic DNA extracted by modified CTAB method and high-salt Iow-pH method was better, and polyphenols, polysaccharides and other impurities were removed more completely. The PCR-SSR and SSCP detection results showed that the genomic DNA extracted by different methods from different tissues of Chenopodium quinoa Willd all could be better amplified, and high-quality strips could be obtained. So the Chenopodium quinoa Willd genomic DNA extracted by the three methods all can be used for subsequent molecular biology research.展开更多
Bioaerosols significantly affect atmospheric processes while they undergo long-range vertical and horizontal transport and influence atmospheric chemistry and physics and climate change.Accumulating evidence suggests ...Bioaerosols significantly affect atmospheric processes while they undergo long-range vertical and horizontal transport and influence atmospheric chemistry and physics and climate change.Accumulating evidence suggests that exposure to bioaerosols may cause adverse health effects,including severe disease.Studies of bioaerosols have primarily focused on their chemical composition and largely neglected their biological composition and the negative effects of biological composition on ecosystems and human health.Here,current molecular methods for the identification,quantification,and distribution of bioaerosol agents are reviewed.Modern developments in environmental microbiology technology would be favorable in elucidation of microbial temporal and spatial distribution in the atmosphere at high resolution.In addition,these provide additional supports for growing evidence that microbial diversity or composition in the bioaerosol is an indispensable environmental aspect linking with public health.展开更多
A basic calculation procedure for the MOSMO method under CNDO/2 approximation is presented in this paper,and performed by using the same parameters as those used in the ordinary CNDO/2 LCAO-MO calculation.The calculat...A basic calculation procedure for the MOSMO method under CNDO/2 approximation is presented in this paper,and performed by using the same parameters as those used in the ordinary CNDO/2 LCAO-MO calculation.The calculated results on the whole are close to those obtained by use of the ordinary CNDO/2 LCAO-MO calculation,illustrating that the presented procedure is reasonable.Due to its simplicity,the presented calculation procedure may be feasible even in very large molecular s ystems.展开更多
High diffraction quality crystals of cucurmosin, a type I ribosome inactivating protein isolated from the sarcocarp of Cucurbita moschata (pumpkin), have been grown under newly optimised conditions. With in-house rota...High diffraction quality crystals of cucurmosin, a type I ribosome inactivating protein isolated from the sarcocarp of Cucurbita moschata (pumpkin), have been grown under newly optimised conditions. With in-house rotating anode X-ray source, these crystals diffract to 1.65 ?resolution which is much higher than that of the previously reported crystals that diffracted only to 3 ?resolution. The crystals belong to space group P212121 with cell parameters a = 41.5, b = 58.4 and c = 99.3 . Molecular replacement studies indicate that the cucurmosin structure is homologous to trichosanthin. The initial structural model has been obtained and the model fitting/ refinement is in progress.展开更多
The structure and properties of molten salt solution o J Li,K|F,Cl system have been investiged by computerized simulation of molecular dynamic method.The partial RDF,the partial molar energy of mixing and the diffusio...The structure and properties of molten salt solution o J Li,K|F,Cl system have been investiged by computerized simulation of molecular dynamic method.The partial RDF,the partial molar energy of mixing and the diffusion coeffients of Li^+,K^+,F^- and Cl^- have been calculated. The results are in agreement with the experimental values.The regularities of the distribution of ions and mieroscopic holes are discussed based on the results of computerized simulation.展开更多
The detection and parameterization of molecular clumps are the first step in studying them.We propose a method based on the Local Density Clustering algorithm while physical parameters of those clumps are measured usi...The detection and parameterization of molecular clumps are the first step in studying them.We propose a method based on the Local Density Clustering algorithm while physical parameters of those clumps are measured using the Multiple Gaussian Model algorithm.One advantage of applying the Local Density Clustering to the clump detection and segmentation,is the high accuracy under different signal-to-noise levels.The Multiple Gaussian Model is able to deal with overlapping clumps whose parameters can reliably be derived.Using simulation and synthetic data,we have verified that the proposed algorithm could accurately characterize the morphology and flux of molecular clumps.The total flux recovery rate in 13CO(J=1-0)line of M16 is measured as 90.2%.The detection rate and the completeness limit are 81.7%and 20 K km s-1 in 13CO(J=1-0)line of M16,respectively.展开更多
[Objectives]The paper was to establish a molecular biological method for identification of bacterial strains.[Methods]The thalli of standard bacterial strains existing in the laboratory were collected and genomic DNA ...[Objectives]The paper was to establish a molecular biological method for identification of bacterial strains.[Methods]The thalli of standard bacterial strains existing in the laboratory were collected and genomic DNA was extracted for amplification of 16S rDNA and gyrB gene.The 16S rDNA and gyrB gene sequences were obtained after sequencing.Sequences were aligned and analyzed via EzBioCloud and NCBI database,and phylogenetic trees were constructed to determine the species relationship of strains.Meantime,they were compared with known strains.[Results]This method could identify 5 standard strains accurately to the species level.The 16S rDNA and gyrB gene sequences were aligned and analyzed in EzBioCloud database and NCBI database.The strain with the max score was consistent with the known strain.And the query cover and ident were both above 99%.[Conclusions]The established molecular biological method for identification of bacterial strains by 16S rDNA and gyrB gene has good accuracy,which effectively solves the problem that the laboratory identification of bacteria relies on traditional methods and the accuracy can not be guaranteed,and further improves the identification ability of laboratory bacterial strains.展开更多
A modified molecular structural mechanics method, based on molecular mechanics and similar to the finite element method, was developed. The energy of a system was expressed by the force field functions of the molecula...A modified molecular structural mechanics method, based on molecular mechanics and similar to the finite element method, was developed. The energy of a system was expressed by the force field functions of the molecular mechanics. Under the small deformation assumption and by the principle of minimum potential energy, the system function was established. The properties of tension and bending of single-walled carbon nanotubes were analyzed. The Young＇s modulus is about 0.36 TPa nm, which agrees perfectly with the results of previous analysis by other researchers. It is found, for the first time, that the Young＇s moduli, for Zigzag nanotubes, are different from each other when the system energy was expressed as the sum of two or three individual energy terms in molecular mechanics. Whereas, the Young＇s moduli were the same for the Armchair nanotubes. It is found, when simulating the bending, that the deflections are closer to the theoretical ones, of the classical elasticity, when the diameter of the carbon nanotube increases.展开更多
Objective: To study the treatment of B-Thalas-semia (ThE) with Chinese herbal medicine for Bushen Yisui (BSYS), its theoretical base and molecular mechanism. Methods: Seventy-eight patients with ThE were treated with ...Objective: To study the treatment of B-Thalas-semia (ThE) with Chinese herbal medicine for Bushen Yisui (BSYS), its theoretical base and molecular mechanism. Methods: Seventy-eight patients with ThE were treated with BSYS recipe (consisted of 11 Chinese herbal drugs as Dogwood fruit, Fleeceflower root, prepared Rehmannia root and turtle shell, etc.) orally taken, 3 times per day, 10 g/time, 3 months as one therapeutic course. Hemoglobin (Hb), red blood cell (RBC), reticulocyte (Ret) and hemoglobin F (HbF) were checked every month. At the same time, PAGE, PVR, PCR-SSCP, RT-PCR, DNA series analysis, mRNA gene expression analysis techniques were used to conduct the systematic gene analysis in patients to study the molecular mechanism of TCM treatment from aspects of gene mutation, gene expression and control-regulation. Results: All the blood criteria in patients after BSYS treatment were improved significantly with clinical symptoms展开更多
Adsorption of FCC dry gas components, hydrogen(H_2), nitrogen(N_2), methane(CH_4), ethane(C_2H_6) and ethylene(C_2H_4) in zeolite Y was studied by performing the Grant Canonical Monte Carlo(GCMC) simulations at 298K a...Adsorption of FCC dry gas components, hydrogen(H_2), nitrogen(N_2), methane(CH_4), ethane(C_2H_6) and ethylene(C_2H_4) in zeolite Y was studied by performing the Grant Canonical Monte Carlo(GCMC) simulations at 298K and 823K and under a pressure range up to 10 MPa. Simulation results were analyzed using the Langmuir model, which presented fitting of dry gas components adsorption to be suggested as the monolayer adsorption. C_2H_4 presented most single adsorption amount, which reached 7.63 mol/kg at 298K under a pressure of 200kPa. Thermodynamic parameters of the Gibbs free energy change, enthalpy change and entropy change were analyzed based on adsorption equilibrium constant obtained from the GCMC simulations. The results suggested that it was more favorable for C_2H_4 to be adsorbed in zeolite Y. Adsorption molecules were in ordered arrangement in the zeolite, and C_2H_4 exhibited a more orderly arrangement than other components. Additionally, a competition in the adsorption of a mixture of dry gas components was found, and supercages were the priority adsorption space. The competition was favorable to CH_4 and C_2H_6, and the competitive power was affected by temperature.展开更多
This paper performs the two-dimensional, soft-sphere molecular dynamics simulations to study the granular segregation in a binary granular mixture with the same size but different density in the container with the saw...This paper performs the two-dimensional, soft-sphere molecular dynamics simulations to study the granular segregation in a binary granular mixture with the same size but different density in the container with the sawtooth base under horizontal vibration. The segregation phase diagram is presented in the acceleration-frequency space. When the acceleration is high enough to result in relative motions of the particles, the system can be in various states （mixed state, vertical and horizontal segregation state）, which depend on both acceleration and frequency. Due to the sawtooth base there is stratified flow effect besides density effect. The density effect raises the light particles. The stratified flow drives the particles in the upper levels to the right and the particles in the lower particles to the left, resulting in the appearance of the left segregation state. The left segregation state can be changed to the right segregation by changing the shape of the sawtooth. As the vibration frequency increases, the stratified flow effect becomes weaker and weaker, so at high vibration frequencies the vertical segregation state appears instead of the left segregation state.展开更多
Black phosphorus （BP） has received attention due to its own higher carrier mobility and layer dependent electronic properties, such as direct band gap. Interestingly, the single layer black phosphorus （SLBP） has h...Black phosphorus （BP） has received attention due to its own higher carrier mobility and layer dependent electronic properties, such as direct band gap. Interestingly, the single layer black phosphorus （SLBP） has had large popularity in applications related to thermoelectric, optoelectronic, and electronic devices. Here, we investigate the phonon spectrum, thermal conductivities, and stress strain effects. Robust anisotropy was mainly observed in the thermal conductivities together with the alongside zigzag （ZZ） direction value, compared to the armchair （AC） directions. We also investigated the attitude of stress that was anisotropic in both directions, and the stress effects were two times greater across the ZZ path than those in the AC direction at a low temperature. We obtained a ~oung＇s modulus of 63.77 and 20.74 GPa in the AC and ZZ directions, respectively, for a strain range of 0.01. These results had good agreement with first principle calculations. Our study here is useful and significant for the thermal tuning of phosphorus-based nanoelectronics and thermalelectric applications of phosphorus.展开更多
The possibility of complex formation by short lysine brush and therapeutic Semax peptides was investigated using molecular dynamics method. Lysine dendrimers and polymer brushes are used for drug and other (e.g., DNA,...The possibility of complex formation by short lysine brush and therapeutic Semax peptides was investigated using molecular dynamics method. Lysine dendrimers and polymer brushes are used for drug and other (e.g., DNA, peptides, and polysaccharides) molecules delivery to different target cells. It is known that they could penetrate blood brain barrier. Since short lysine brush is nontoxic, a system containing of such brush and 8 oppositely charged Semax peptides was studied. It was obtained that stable complexes consisting of brush and peptides formed and structures of these complexes were investigated. Such complex can be used in future for delivery of Semax peptides to brain since these peptides have significant antioxidant, antihypoxic and neuroprotective effects.展开更多
Considering the recommended indications for Helicobacter pylori(H.pylori)eradication therapy and the broad spectrum of available diagnostic methods,a reliable diagnosis is mandatory both before and after eradication t...Considering the recommended indications for Helicobacter pylori(H.pylori)eradication therapy and the broad spectrum of available diagnostic methods,a reliable diagnosis is mandatory both before and after eradication therapy.Only highly accurate tests should be used in clinical practice,and the sensitivity and specificity of an adequate test should exceed 90%.The choice of tests should take into account clinical circumstances,the likelihood ratio of positive and negative tests,the cost-effectiveness of the testing strategy and the availability of the tests.This review concerns some of the most recent developments in diagnostic methods of H.pylori infection,namely the contribution of novel endoscopic evaluation methodologies for the diagnosis of H.pylori infection,such as magnifying endoscopy techniques and chromoendoscopy.In addition,the diagnostic contribution of histology and the urea breath test was explored recently in specific clinical settings and patient groups.Recent studies recommend enhancing the number of biopsy fragments for the rapid urease test.Bacterial culture from the gastric biopsy is the gold standard technique,and is recommended for antibiotic susceptibility test.Serology is used for initial screening and the stool antigen test is particularly used when the urea breath test is not available,while molecular methods have gained attention mostly for detecting antibiotic resistance.展开更多
The scuticociliatid ciliates Ancistrum haliotis and A.crassum are parasites that may cause high mortality in the cultured abalone Haliotis spp.and the bivalve Ruditapes philippinarum.Traditional identification with si...The scuticociliatid ciliates Ancistrum haliotis and A.crassum are parasites that may cause high mortality in the cultured abalone Haliotis spp.and the bivalve Ruditapes philippinarum.Traditional identification with silver staining methods is hampered by their morphological similarities to closely related species and the complicated procedures of morphological analysis.We designed two SSU rRNA-targeted oligonucleotide probes labeled with a fluorochrome,and optimized the fluorescence in situ hybridization(FISH)protocols for identification of A.halioti and A.crassum,respectively.The assays resulted in a clear identification by strong fluorescence signals from the oligonucleotide probes.The method can be used for quick and accurate quantitative analysis of A.haliotis and A.crassum infections on host molluscs.展开更多
Since many waterborne diseases are caused by human pathogenic viruses,virus monitoring of drinking water(DW)and DW sources is crucial for public health.Therefore,the aim of this review was to describe the occurrence o...Since many waterborne diseases are caused by human pathogenic viruses,virus monitoring of drinking water(DW)and DW sources is crucial for public health.Therefore,the aim of this review was to describe the occurrence of human pathogenic viruses in DW and DW sources;the occurrence of two viruses proposed as novel indicators of human faecal contamination(Peppermild mottle virus and Tobacco mosaic virus)was also reported.This research was focused on articles that assessed viral occurrence using molecular methods in the surface water used for DW production(SW-D),groundwater used for DW production(GW-D),DW and bottled-DW(BW).A total of 1544 studies published in the last 10 years were analysed,and 79 were ultimately included.In considering the detection methods,filtration is the most common concentration technique,while quantitative polymerase chain reaction is the most common quantification technique.Regarding virus occurrence in SW-D,GW-D,and DW,high percentages of positive samples were reported for adenovirus,polyomavirus and Pepper mild mottle virus.Viral genomes were frequently detected in SW-D and rarely in GW-D,suggesting that GW-D may be a safe DW source.Viral genomes were also detected in DW,posing a possible threat to human health.The lowest percentages of positive samples were found in Europe,while the highest were found in Asia and South America.Only three articles assessed viral occurrence in BW.This review highlights the lack of method standardization and the need for legislation updates.展开更多
文摘Human respiratory system is harbored by a vast array of transient and normal microbial flora.A number of pathogenic viruses were diagnosed from samples in different occasions from mild to severe infections of respiratory tract.Molecular methods were developed for detection of these viruses during last two decades.Nucleic acid amplification methods were introduced for rapid and accurate diagnosis of pathogenic viruses.Multiplex detection systems were employed to identify a panel of pathogenic viruses,which requires specialized kits and instruments in some cases.This review summarizes different types of molecular approaches which were developed with time and applied for the detection of pathogenic viruses associated with infections of the respiratory system.
文摘Sexually transmitted infections (STIs) represent a public health problem due to their high prevalence worldwide and the emergence of multidrug resistance of responsible microorganisms. Medical laboratory diagnosis of sexually transmitted genital infections by traditional methods as culture remains extremely delicate, difficult or impossible (to find extremely fragile organisms that can be cultured). Thus, molecular techniques constitute an alternative to improve accurate diagnostic, personalized patient treatment, and public health. A total of 83 clinical samples including urethral discharge and urine samples from individual patients with symptoms of urethritis received were analyzed using traditional methods and a commercial real-time PCR (qPCR) method. Out of 83 urethritis patients, n = 55 (66.26%) were positive for at least one of the STI pathogens detected by qPCR. qPCR assay was more sensitive (50/83, positive cases) compared to culture (15/83, positive cases) and light microscopy (28/83, positive cases). The most prevalent NTD pathogen in the suspected patients was N. gonorrhoeae with 60.24% (50/83) based on real-time PCR diagnosis. Among the positive cases of STI pathogens, Neisseria gonorrhoeae had the highest frequency 49/55 (89.01%) followed by low frequencies of Trichomonas vaginalis 4/55 (7.27%) and Chlamydia trachomatis 1/55 (1.82%). This highlights the high prevalence of N. gonorrhoeae infection in male urethritis patients and a very important misdiagnosis using traditional routine methods in Burkina Faso by medical laboratories. Thus, this situation may negatively impact patients’ personalized treatment and care and public health with the possible rapid emergence of multidrug-resistant strains. This study also highlights the urgent need to optimize culture for the diagnosis of NTD pathogens in Burkina Faso and the usefulness and the need for the introduction of molecular diagnostic methods in routine diagnosis for the detection of NTD pathogens in the medical laboratories in Burkina Faso.
基金financially supported by the Science and Technology Innovation Program of Hunan Province(2024AQ2008)。
文摘The fly ash from waste incineration poses a serious threat to human health due to its high content of dioxins.Hydrothermal treatment is an efficient and clean method on the decomposition and detoxifying of fly ash.To study the degradation mechanism of dioxins,this paper uses molecular dynamics(MD)to simulate the hydrothermal reaction process of polychlorinated dibenzo-p-dioxins(PCDDs)under different conditions,and the degradation mechanism of PCDDs is obtained.The results show that the degradation of PCDDs includes two pathways:the first pathway is the substitution of Cl groups by hydroxyl groups to form low-chlorine substitution products through direct hydrogenation,and the second pathway is the formation of non-toxic benzene ring structures accompanied by the cleavage of C—O bonds.The two degradation pathways of PCDDs well explain the changes in toxicity before and after the hydrothermal treatment of fly ash,which is consistent with experimental results.This study provides theoretical guidance for the harmless treatment process of fly ash via hydrothermal method.
文摘AIM To compare(1) demographics in urea breath test(UBT) vs endoscopy patients; and(2) the molecular detection of antibiotic resistance in stool vs biopsy samples.METHODS Six hundred and sixteen adult patients undergoing endoscopy or a UBT were prospectively recruited to the study. The Geno Type Helico DR assay was used to detect Helicobacter pylori(H. pylori) and antibiotic resistance using biopsy and/or stool samples from CLOpositive endoscopy patients and stool samples from UBT-positive patients. RESULTS Infection rates were significantly higher in patients referred for a UBT than endoscopy(overall rates: 33% vs 19%; treatment-na?ve patients: 33% vs 14.7%, respectively). H. pylori-infected UBT patients were younger than H. pylori-infected endoscopy patients(41.4 vs 48.4 years, respectively, P < 0.005), with a higher percentage of H. pylori-infected males in the endoscopy-compared to the UBT-cohort(52.6% vs 33.3%, P = 0.03). The Geno Type Helico DR assay was more accurate at detecting H. pylori infection using biopsy samples than stool samples [98.2%(n = 54/55) vs 80.3%(n =53/66), P < 0.005]. Subset analysis using stool and biopsy samples from CLO-positive endoscopy patients revealed a higher detection rate ofresistance-associated mutations using stool samples compared to biopsies. The concordance rates between stool and biopsy samples for the detection of H. pylori DNA, clarithromycin and fluoroquinolone resistance were just 85%, 53% and 35%, respectively. CONCLUSION Differences between endoscopy and UBT patients provide a rationale for non-invasive detection of H. pylori antibiotic resistance. However, the Geno Type Helico DR assay is an unsuitable approach.
基金Supported by National Natural Science Foundation of China(31301372)Key Project of Science and Technology Plan of Zhejiang Province(2011C12030)Innovation Training Project of Zhejiang Agriculture and Forestry University(201301004)~~
文摘To rapidly obtain high-quality genomic DNA from Chenopodium quinoa Willd, the genomic DAN in different tissues （leaves, stems and roots） of Chenopodi- um quinoa Willd was extracted by modified CTAB method, SDS method and high- salt Iow-pH method, respectively. The quality and yield of extracted DNA was deter- mined using agarose gel electrophoresis and UV spectrophotometry. At the same time, the PCR-SSR and SSCP molecular detection was also performed. The results showed that the gel test strips, without obvious decomposition, of all the extraction methods were relatively obvious; the genomic DNA yield extracted by modified CTAB method was highest, followed by that by SDS method, and the genomic DNA extracted by high-salt Iow-pH method was lowest： the genomic DNA yields extracted by different methods from Chenopodium quinoa Wiltd leaves were all high- er than those from roots and stems; the quality of Chenopodium quinoa Willd ge- nomic DNA extracted by modified CTAB method and high-salt Iow-pH method was better, and polyphenols, polysaccharides and other impurities were removed more completely. The PCR-SSR and SSCP detection results showed that the genomic DNA extracted by different methods from different tissues of Chenopodium quinoa Willd all could be better amplified, and high-quality strips could be obtained. So the Chenopodium quinoa Willd genomic DNA extracted by the three methods all can be used for subsequent molecular biology research.
基金supported by the National Research Foundation(NRF)of Korea via a grant(No.2011-0030040)funded by the Korea government(MSIP)GAIA project from Korea Ministry of Environment for the performance of this study
文摘Bioaerosols significantly affect atmospheric processes while they undergo long-range vertical and horizontal transport and influence atmospheric chemistry and physics and climate change.Accumulating evidence suggests that exposure to bioaerosols may cause adverse health effects,including severe disease.Studies of bioaerosols have primarily focused on their chemical composition and largely neglected their biological composition and the negative effects of biological composition on ecosystems and human health.Here,current molecular methods for the identification,quantification,and distribution of bioaerosol agents are reviewed.Modern developments in environmental microbiology technology would be favorable in elucidation of microbial temporal and spatial distribution in the atmosphere at high resolution.In addition,these provide additional supports for growing evidence that microbial diversity or composition in the bioaerosol is an indispensable environmental aspect linking with public health.
文摘A basic calculation procedure for the MOSMO method under CNDO/2 approximation is presented in this paper,and performed by using the same parameters as those used in the ordinary CNDO/2 LCAO-MO calculation.The calculated results on the whole are close to those obtained by use of the ordinary CNDO/2 LCAO-MO calculation,illustrating that the presented procedure is reasonable.Due to its simplicity,the presented calculation procedure may be feasible even in very large molecular s ystems.
基金Supported by the National Natural Science Foundation of China (39970872) NSF of Fujian province+1 种基金 and International Cooperation program of Fujian province to the State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Struct
文摘High diffraction quality crystals of cucurmosin, a type I ribosome inactivating protein isolated from the sarcocarp of Cucurbita moschata (pumpkin), have been grown under newly optimised conditions. With in-house rotating anode X-ray source, these crystals diffract to 1.65 ?resolution which is much higher than that of the previously reported crystals that diffracted only to 3 ?resolution. The crystals belong to space group P212121 with cell parameters a = 41.5, b = 58.4 and c = 99.3 . Molecular replacement studies indicate that the cucurmosin structure is homologous to trichosanthin. The initial structural model has been obtained and the model fitting/ refinement is in progress.
文摘The structure and properties of molten salt solution o J Li,K|F,Cl system have been investiged by computerized simulation of molecular dynamic method.The partial RDF,the partial molar energy of mixing and the diffusion coeffients of Li^+,K^+,F^- and Cl^- have been calculated. The results are in agreement with the experimental values.The regularities of the distribution of ions and mieroscopic holes are discussed based on the results of computerized simulation.
基金Supported by the National Natural Science Foundation of China。
文摘The detection and parameterization of molecular clumps are the first step in studying them.We propose a method based on the Local Density Clustering algorithm while physical parameters of those clumps are measured using the Multiple Gaussian Model algorithm.One advantage of applying the Local Density Clustering to the clump detection and segmentation,is the high accuracy under different signal-to-noise levels.The Multiple Gaussian Model is able to deal with overlapping clumps whose parameters can reliably be derived.Using simulation and synthetic data,we have verified that the proposed algorithm could accurately characterize the morphology and flux of molecular clumps.The total flux recovery rate in 13CO(J=1-0)line of M16 is measured as 90.2%.The detection rate and the completeness limit are 81.7%and 20 K km s-1 in 13CO(J=1-0)line of M16,respectively.
基金Supported by Special Project of"Grassland Talents"in Inner Mongolia.
文摘[Objectives]The paper was to establish a molecular biological method for identification of bacterial strains.[Methods]The thalli of standard bacterial strains existing in the laboratory were collected and genomic DNA was extracted for amplification of 16S rDNA and gyrB gene.The 16S rDNA and gyrB gene sequences were obtained after sequencing.Sequences were aligned and analyzed via EzBioCloud and NCBI database,and phylogenetic trees were constructed to determine the species relationship of strains.Meantime,they were compared with known strains.[Results]This method could identify 5 standard strains accurately to the species level.The 16S rDNA and gyrB gene sequences were aligned and analyzed in EzBioCloud database and NCBI database.The strain with the max score was consistent with the known strain.And the query cover and ident were both above 99%.[Conclusions]The established molecular biological method for identification of bacterial strains by 16S rDNA and gyrB gene has good accuracy,which effectively solves the problem that the laboratory identification of bacteria relies on traditional methods and the accuracy can not be guaranteed,and further improves the identification ability of laboratory bacterial strains.
文摘A modified molecular structural mechanics method, based on molecular mechanics and similar to the finite element method, was developed. The energy of a system was expressed by the force field functions of the molecular mechanics. Under the small deformation assumption and by the principle of minimum potential energy, the system function was established. The properties of tension and bending of single-walled carbon nanotubes were analyzed. The Young＇s modulus is about 0.36 TPa nm, which agrees perfectly with the results of previous analysis by other researchers. It is found, for the first time, that the Young＇s moduli, for Zigzag nanotubes, are different from each other when the system energy was expressed as the sum of two or three individual energy terms in molecular mechanics. Whereas, the Young＇s moduli were the same for the Armchair nanotubes. It is found, when simulating the bending, that the deflections are closer to the theoretical ones, of the classical elasticity, when the diameter of the carbon nanotube increases.
文摘Objective: To study the treatment of B-Thalas-semia (ThE) with Chinese herbal medicine for Bushen Yisui (BSYS), its theoretical base and molecular mechanism. Methods: Seventy-eight patients with ThE were treated with BSYS recipe (consisted of 11 Chinese herbal drugs as Dogwood fruit, Fleeceflower root, prepared Rehmannia root and turtle shell, etc.) orally taken, 3 times per day, 10 g/time, 3 months as one therapeutic course. Hemoglobin (Hb), red blood cell (RBC), reticulocyte (Ret) and hemoglobin F (HbF) were checked every month. At the same time, PAGE, PVR, PCR-SSCP, RT-PCR, DNA series analysis, mRNA gene expression analysis techniques were used to conduct the systematic gene analysis in patients to study the molecular mechanism of TCM treatment from aspects of gene mutation, gene expression and control-regulation. Results: All the blood criteria in patients after BSYS treatment were improved significantly with clinical symptoms
基金financial support from the National Natural Science Foundation of China (No. 41302101 and No. 21476263)
文摘Adsorption of FCC dry gas components, hydrogen(H_2), nitrogen(N_2), methane(CH_4), ethane(C_2H_6) and ethylene(C_2H_4) in zeolite Y was studied by performing the Grant Canonical Monte Carlo(GCMC) simulations at 298K and 823K and under a pressure range up to 10 MPa. Simulation results were analyzed using the Langmuir model, which presented fitting of dry gas components adsorption to be suggested as the monolayer adsorption. C_2H_4 presented most single adsorption amount, which reached 7.63 mol/kg at 298K under a pressure of 200kPa. Thermodynamic parameters of the Gibbs free energy change, enthalpy change and entropy change were analyzed based on adsorption equilibrium constant obtained from the GCMC simulations. The results suggested that it was more favorable for C_2H_4 to be adsorbed in zeolite Y. Adsorption molecules were in ordered arrangement in the zeolite, and C_2H_4 exhibited a more orderly arrangement than other components. Additionally, a competition in the adsorption of a mixture of dry gas components was found, and supercages were the priority adsorption space. The competition was favorable to CH_4 and C_2H_6, and the competitive power was affected by temperature.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10674135)by the Centre for Computational Science,Hefei Institutes of Physical Sciences,China
文摘This paper performs the two-dimensional, soft-sphere molecular dynamics simulations to study the granular segregation in a binary granular mixture with the same size but different density in the container with the sawtooth base under horizontal vibration. The segregation phase diagram is presented in the acceleration-frequency space. When the acceleration is high enough to result in relative motions of the particles, the system can be in various states （mixed state, vertical and horizontal segregation state）, which depend on both acceleration and frequency. Due to the sawtooth base there is stratified flow effect besides density effect. The density effect raises the light particles. The stratified flow drives the particles in the upper levels to the right and the particles in the lower particles to the left, resulting in the appearance of the left segregation state. The left segregation state can be changed to the right segregation by changing the shape of the sawtooth. As the vibration frequency increases, the stratified flow effect becomes weaker and weaker, so at high vibration frequencies the vertical segregation state appears instead of the left segregation state.
文摘Black phosphorus （BP） has received attention due to its own higher carrier mobility and layer dependent electronic properties, such as direct band gap. Interestingly, the single layer black phosphorus （SLBP） has had large popularity in applications related to thermoelectric, optoelectronic, and electronic devices. Here, we investigate the phonon spectrum, thermal conductivities, and stress strain effects. Robust anisotropy was mainly observed in the thermal conductivities together with the alongside zigzag （ZZ） direction value, compared to the armchair （AC） directions. We also investigated the attitude of stress that was anisotropic in both directions, and the stress effects were two times greater across the ZZ path than those in the AC direction at a low temperature. We obtained a ~oung＇s modulus of 63.77 and 20.74 GPa in the AC and ZZ directions, respectively, for a strain range of 0.01. These results had good agreement with first principle calculations. Our study here is useful and significant for the thermal tuning of phosphorus-based nanoelectronics and thermalelectric applications of phosphorus.
文摘The possibility of complex formation by short lysine brush and therapeutic Semax peptides was investigated using molecular dynamics method. Lysine dendrimers and polymer brushes are used for drug and other (e.g., DNA, peptides, and polysaccharides) molecules delivery to different target cells. It is known that they could penetrate blood brain barrier. Since short lysine brush is nontoxic, a system containing of such brush and 8 oppositely charged Semax peptides was studied. It was obtained that stable complexes consisting of brush and peptides formed and structures of these complexes were investigated. Such complex can be used in future for delivery of Semax peptides to brain since these peptides have significant antioxidant, antihypoxic and neuroprotective effects.
文摘Considering the recommended indications for Helicobacter pylori(H.pylori)eradication therapy and the broad spectrum of available diagnostic methods,a reliable diagnosis is mandatory both before and after eradication therapy.Only highly accurate tests should be used in clinical practice,and the sensitivity and specificity of an adequate test should exceed 90%.The choice of tests should take into account clinical circumstances,the likelihood ratio of positive and negative tests,the cost-effectiveness of the testing strategy and the availability of the tests.This review concerns some of the most recent developments in diagnostic methods of H.pylori infection,namely the contribution of novel endoscopic evaluation methodologies for the diagnosis of H.pylori infection,such as magnifying endoscopy techniques and chromoendoscopy.In addition,the diagnostic contribution of histology and the urea breath test was explored recently in specific clinical settings and patient groups.Recent studies recommend enhancing the number of biopsy fragments for the rapid urease test.Bacterial culture from the gastric biopsy is the gold standard technique,and is recommended for antibiotic susceptibility test.Serology is used for initial screening and the stool antigen test is particularly used when the urea breath test is not available,while molecular methods have gained attention mostly for detecting antibiotic resistance.
基金The National Natural Science Foundation of China under contract Nos 41876171 and 41406171
文摘The scuticociliatid ciliates Ancistrum haliotis and A.crassum are parasites that may cause high mortality in the cultured abalone Haliotis spp.and the bivalve Ruditapes philippinarum.Traditional identification with silver staining methods is hampered by their morphological similarities to closely related species and the complicated procedures of morphological analysis.We designed two SSU rRNA-targeted oligonucleotide probes labeled with a fluorochrome,and optimized the fluorescence in situ hybridization(FISH)protocols for identification of A.halioti and A.crassum,respectively.The assays resulted in a clear identification by strong fluorescence signals from the oligonucleotide probes.The method can be used for quick and accurate quantitative analysis of A.haliotis and A.crassum infections on host molluscs.
基金supported by the University of Torino and by Piedmont Region.
文摘Since many waterborne diseases are caused by human pathogenic viruses,virus monitoring of drinking water(DW)and DW sources is crucial for public health.Therefore,the aim of this review was to describe the occurrence of human pathogenic viruses in DW and DW sources;the occurrence of two viruses proposed as novel indicators of human faecal contamination(Peppermild mottle virus and Tobacco mosaic virus)was also reported.This research was focused on articles that assessed viral occurrence using molecular methods in the surface water used for DW production(SW-D),groundwater used for DW production(GW-D),DW and bottled-DW(BW).A total of 1544 studies published in the last 10 years were analysed,and 79 were ultimately included.In considering the detection methods,filtration is the most common concentration technique,while quantitative polymerase chain reaction is the most common quantification technique.Regarding virus occurrence in SW-D,GW-D,and DW,high percentages of positive samples were reported for adenovirus,polyomavirus and Pepper mild mottle virus.Viral genomes were frequently detected in SW-D and rarely in GW-D,suggesting that GW-D may be a safe DW source.Viral genomes were also detected in DW,posing a possible threat to human health.The lowest percentages of positive samples were found in Europe,while the highest were found in Asia and South America.Only three articles assessed viral occurrence in BW.This review highlights the lack of method standardization and the need for legislation updates.
