BACKGROUND End-stage liver disease is a global health complication with high prevalence and limited treatment options.Cell-based therapies using mesenchymal stem cells(MSCs)emerged as an alternative approach to suppor...BACKGROUND End-stage liver disease is a global health complication with high prevalence and limited treatment options.Cell-based therapies using mesenchymal stem cells(MSCs)emerged as an alternative approach to support hepatic regeneration.In vitro preconditioning strategies have been employed to strengthen the regenerative and differentiation potential of MSCs towards hepatic lineage.Chemical compounds of the triterpene class;glycyrrhizic acid(GA)and 18β-glycyrrhetinic acid(GT)possess diverse therapeutic properties including hepatoprotection and anti-fibrosis characteristics.They are capable of modulating several signaling pathways that are crucial in hepatic regeneration.Preconditioning with hepato-protective triterpenes may stimulate MSC fate transition towards hepatocytes.AIM To explore the effect of GA and GT on hepatic differentiation of human umbilical cord-MSCs(hUC-MSCs).METHODS hUC-MSCs were isolated and characterized phenotypically by flow cytometry and immunocytochemistry for the expression of MSC-associated surface molecules.Isolated cells were treated with GA,GT,and their combination for 24 h and then analyzed at three time points;day 7,14,and 21.qRT-PCR was performed for the expression of hepatic genes.Expression of hepatic proteins was analyzed by immunocytochemistry at day 21.Periodic acid Schiff staining was performed to determine the functional ability of treated cells.RESULTS The fusiform-shaped morphology of MSCs in the treatment groups in comparison with the untreated control,eventually progressed towards the polygonal morphology of hepatocytes with the passage of time.The temporal transcriptional profile of preconditioned MSCs displayed significant expression of hepatic genes with increasing time of differentiation.Preconditioned cells showed positive expression of hepatocyte-specific proteins.The results were further corroborated by positive periodic acid Schiff staining,indicating the presence of glycogen in their cytoplasm.Moreover,bi-nucleated cells,which is the typical feature of hepatocytes,were also seen in the preconditioned cells.CONCLUSION Preconditioning with glycyrrhizic acid,18β-glycyrrhetinic acid and their combination,successfully differentiates hUC-MSCs into hepatic-like cells.These MSCs may serve as a better therapeutic option for degenerative liver diseases in future.展开更多
Dengue virus(DENV) and Zika virus(ZIKV) have spread throughout many countries in the developing world and infect millions of people every year, causing severe harm to human health and the economy. Unfortunately, there...Dengue virus(DENV) and Zika virus(ZIKV) have spread throughout many countries in the developing world and infect millions of people every year, causing severe harm to human health and the economy. Unfortunately, there are few effective vaccines and therapies available against these viruses. Therefore, the discovery of new antiviral agents is critical.Herein, a scorpion venom peptide(Smp76) characterized from Scorpio maurus palmatus was successfully expressed and purified in Escherichia coli BL21(DE3). The recombinant Smp76(rSmp76) was found to effectively inhibit DENV and ZIKV infections in a dose-dependent manner in both cultured cell lines and primary mouse macrophages. Interestingly,rSmp76 did not inactivate the viral particles directly but suppressed the established viral infection, similar to the effect of interferon(IFN)-b. Mechanistically, rSmp76 was revealed to upregulate the expression of IFN-b by activating interferon regulatory transcription factor 3(IRF3) phosphorylation, enhancing the type-Ⅰ IFN response and inhibiting viral infection.This mechanism is significantly different from traditional virucidal antimicrobial peptides(AMPs). Overall, the scorpion venom peptide Smp76 is a potential new antiviral agent with a unique mechanism involving type-Ⅰ IFN responses,demonstrating that natural AMPs can enhance immunity by functioning as immunomodulators.展开更多
The title compounds 3-（3,5-bis（trifluoromethyl）phenyl）quinoline （1） and 3-（4- fluoro-3-methylphenyl）quinoline （2） were synthesized through Suzuki-Miyaura Cross coupling reaction of 3-bromoquinoloine with ary...The title compounds 3-（3,5-bis（trifluoromethyl）phenyl）quinoline （1） and 3-（4- fluoro-3-methylphenyl）quinoline （2） were synthesized through Suzuki-Miyaura Cross coupling reaction of 3-bromoquinoloine with aryl boronic acids. The title compounds were characterized by single-crystal X-ray diffraction, 1H NMR, 13C NMR, El-MS, elemental analysis and IR. The crystals of 3-（3,5-bis（trifluoromethyl）phenyl）quinoline （C17H9F6N, Mr = 341.25） belongs to the monoclinic system, space group P21n, a = 12.3072（13）, b = 4.9378（6）, c = 24.493（2） A, V= 1473.1（3） A3, Z = 4, Dc = 1.539 Mg m-3, 2 - 0.71073A, μ = 0.144 mm^-1, F（000） = 688, the final R = 0.0715 and wR = 0.1873 for 1875 obserwed reflections with I 〉 2σ（I） and the crystal of 3-（4-fluoro-3- methylphenyl）quinoline （C16H12FN, Mr= 237.27） belongs to the orthorhombic system, space group Pca21, a = 23.794（2）, b = 3.9094（3）, c = 25.669（2） A, V = 2387.7（4） A3, Z = 8, D, = 1.320 Mg m-3, 2 = 0.71073 A, μ = 0.088 mm-1, F（000） = 992, the final R = 0.0534 and wR = 0.1188 for 2270 observed reflections with I 〉 2σ（I）.展开更多
BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tis...BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tissue.Cardiac tissue engineering using biomaterial scaffolds combined with stem cells and bioactive molecules could be a highly promising approach for cardiac repair.Use of biomaterials can provide suitable microenvironment to the cells and can solve cell engraftment problems associated with cell transplantation alone.Mesenchymal stem cells(MSCs)are potential candidates in cardiac tissue engineering because of their multilineage differentiation potential and ease of isolation.Use of DNA methyl transferase inhibitor,such as zebularine,in combination with three-dimensional(3D)scaffold can promote efficient MSC differentiation into cardiac lineage,as epigenetic modifications play a fundamental role in determining cell fate and lineage specific gene expression.AIM To investigate the role of collagen scaffold and zebularine in the differentiation of rat bone marrow(BM)-MSCs and their subsequent in vivo effects.METHODS MSCs were isolated from rat BM and characterized morphologically,immunophenotypically and by multilineage differentiation potential.MSCs were seeded in collagen scaffold and treated with 3μmol/L zebularine in three different ways.Cytotoxicity analysis was done and cardiac differentiation was analyzed at the gene and protein levels.Treated and untreated MSC-seeded scaffolds were transplanted in the rat myocardial infarction(MI)model and cardiac function was assessed by echocardiography.Cell tracking was performed by DiI dye labeling,while regeneration and neovascularization were evaluated by histological and immunohistochemical analysis,respectively.RESULTS MSCs were successfully isolated and seeded in collagen scaffold.Cytotoxicity analysis revealed that zebularine was not cytotoxic in any of the treatment groups.Cardiac differentiation analysis showed more pronounced results in the type 3 treatment group which was subsequently chosen for the transplantation in the in vivo MI model.Significant improvement in cardiac function was observed in the zebularine treated MSC-seeded scaffold group as compared to the MI control.Histological analysis also showed reduction in fibrotic scar,improvement in left ventricular wall thickness and preservation of ventricular remodeling in the zebularine treated MSC-seeded scaffold group.Immunohistochemical analysis revealed significant expression of cardiac proteins in DiI labeled transplanted cells and a significant increase in the number of blood vessels in the zebularine treated MSC-seeded collagen scaffold transplanted group.CONCLUSION Combination of 3D collagen scaffold and zebularine treatment enhances cardiac differentiation potential of MSCs,improves cell engraftment at the infarcted region,reduces infarct size and improves cardiac function.展开更多
A novel {[bis（pyridine-κN）bis（3,5-dinitrosalicylato κ-O,O＇）Zn（Ⅱ）][bis（pyridine-κN）Zn（Ⅱ）]}（C_（34）H_（24）N_8O_（14）Zn_2） was synthesized by a self-assemble method at room temperature. The molecular...A novel {[bis（pyridine-κN）bis（3,5-dinitrosalicylato κ-O,O＇）Zn（Ⅱ）][bis（pyridine-κN）Zn（Ⅱ）]}（C_（34）H_（24）N_8O_（14）Zn_2） was synthesized by a self-assemble method at room temperature. The molecular structure was determined by single-crystal X-ray analysis. The compound crystallizes in the monoclinic system, space group P2_1/n with a = 12.2156, b = 13.5696, c = 22.5602 A, β = 90.061o, Z = 4 and V = 3739.6（3）A^3. The new 1D binuclear coordination polymer {[bis（py-κN）bis（3,5-dinitrosal κ-O,O′） Zn（Ⅱ）][bis（py-κN）Zn（Ⅱ）]} resulted from two different types of moieties. The polymer [bis（py-κN）bis（3,5-dinitrosal κ-O,O′）Zn（Ⅱ）] unit is connected with [bis（py-κN） Zn（Ⅱ）] by zigzag topology. One zinc（Ⅱ） cation has a six-fold coordination environment, in which the metal atom is connected with four oxygen atoms of two 3,5-dinitrosalicylic acids to form equatorial bonds and two nitrogen atoms of pyridine to generate the axial bonds. Other four-fold nucleus contain two Zn-O bonds from different 3,5-dinitrosalicylic acids and two bonds with the Natom of pyridine. Antimicrobial assay results indicated that the compound showed moderate activities against different bacterial and fungal strains.展开更多
The oxidations of D-fructose and D-lactose were monitored spectrophotometrically by potassium permanganate in acidic medium at λmax 545 nm. Reaction demonstrated that the two oxidative species of permanganate were in...The oxidations of D-fructose and D-lactose were monitored spectrophotometrically by potassium permanganate in acidic medium at λmax 545 nm. Reaction demonstrated that the two oxidative species of permanganate were involved in an acidic oxidation of the sugars. It was established that respective acids of sugars as well as arabinonic and formic acid were the oxidation products. Respective acids of sugars were the results of reactive oxygen species of permanganate ions in acidic conditions while arabinonic and formic acids due to the cleavage of C__C bond through MnO-4 species. It was first order kinetics with respect to [MnO-4 ], [fructose], [lactose] and [H+]. Hg was used to accelerate the slow oxidation of lactose. Effect of varying salt electrolyte concentration was insignificant showing that the molecular species was involved in the rate determining step. Formic and arabinonic acids and respective acids were analyzed through spot and spectroscopic studies respectively. Reaction was monitored at different temperatures and thermodynamics activation parameters were determined. A mechanism consistent with kinetic studies, spectral evidences, stoichiometry of the reactions and product analysis has been proposed for the oxidation of fructose and lactose in absence and presence of catalyst respectively.展开更多
Exposure to toxic chemicals appears to be one of the major factors in the onset of Schizophrenia. Present study was designed to find out the association of socio-economic, clinical and heavy metals such as chromium (C...Exposure to toxic chemicals appears to be one of the major factors in the onset of Schizophrenia. Present study was designed to find out the association of socio-economic, clinical and heavy metals such as chromium (Cr), lead (Pb) copper (Cu), zinc (Zn), iron (Fe), manganese (Mn) selenium (Se) and arsenic (As) as the principle environmental factors that appear to impact schizophrenic condition in Pakistani population. In this study we have tried to expose some factors such as drug abuse, marital status, education, monthly income that could be related to the disease. These parameters were not investigated before in Pakistani subjects. A self-made questionnaire was developed to collect and record the history of patient’s social and economical status. The level of transition metals in the whole blood was also measured by using Inductive couple plasma optical emission spectroscopy (ICP-OES). Present study has found higher levels of Cr, Pb, Zn, Se, As and Cu and lower levels of Fe and Mn in the blood of newly diagnosed (ND) patients when compared to the controls. While comparing ND with the patients who were on medication (Old Diagnosed) we, found lower level of these metals except for copper in ND. However no significant differences were observed between any trace metal levels between the studied groups. The survey concludes that economic status, marital status and illegal drugs are significantly associated with schizophrenia. Pakistani men who use cannabis are significantly higher in numbers when compared to women in acquiring the psychiatric symptoms.展开更多
In present work chitosan functionalized magnetic nanoparticles (CMNPs) were successfully prepared and investigated for the removal of Reactive Orange 107 dye (RO 107) from water. The chitosan was extracted from shrimp...In present work chitosan functionalized magnetic nanoparticles (CMNPs) were successfully prepared and investigated for the removal of Reactive Orange 107 dye (RO 107) from water. The chitosan was extracted from shrimp shells (Penaeus merguiensis) and was characterized by solubility test and fourier transform infrared spectroscopy (FTIR). Degree of deacetylation of chitosan was examined by 1H-NMR and potentiometric titration method. Thereafter, the chitosan was used for synthesis of CMNPs. The synthesized CMNPs were characterized by FTIR, scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), thermal gravimetric analysis (TGA) and atomic force microscopy (AFM). Effects of various variables such as contact time, pH, stirring speed, adsorbent dosage, temperature, and concentration of electrolyte on extraction efficiency were evaluated. Freundlich isotherm model fits better that shows the removal of RO 107 with CMNPs by multilayer adsorption behaviour. Furthermore, kinetic study showed that adsorption process followed pseudo-second order kinetic model regulated by chemisorption. Thermodynamic analysis explained that adsorption of RO 107 onto CMNPs was endothermic as well as spontaneous. The developed CNMPs were applied to environmental remediation of spiked RO 107 treated waste water samples with 96.20% removal potential, hence, offered an effective sorbent for removal of RO 107 contaminated water samples.展开更多
Introduction:Past incidences have been recorded relating to mishandling of hazardous material either due to insufficient knowledge or inappropriate equipment resulting in the indirect transfer of infectious agents.It ...Introduction:Past incidences have been recorded relating to mishandling of hazardous material either due to insufficient knowledge or inappropriate equipment resulting in the indirect transfer of infectious agents.It is necessary to identify gaps that inhibit proper protection of healthcare professionals from being inadvertently exposed to biological risks.Methods:A cross sectional study was conducted at multiple laboratories across Karachi,Pakistan from January to August 2018.Descriptive questionnaire was used to record data about types and usage of Biological Safety Cabinets(BSCs),along with policies and practices adapted for its certification.Results:A total of 30 laboratories were visited which included Clinical/Biomedical,University hospital,R&D and animal laboratories.Among these 60%always used BSCs,30%periodically used BSCs while 10%did not have any BSCs.Among these facilities 63.6%had BSC class II-A2,39.9%had BSC class II-B2,4.5%had BSC class III and only 0.9%had BSC class I cabinet.No protocols for field certification of BSCs were available.Conclusion:Establishment of biosafety training sessions,implementation and development of protocol for field certification for proper and safe use of BSCs on a local basis accompanied by continuous monitoring is required,for creating a safe environment for all laboratory staff.展开更多
Soil-borne pathogens,e.g.,Plasmodiophora brassicae,causes devastating clubroot disease,and existing identified resistance(R)genes has been broken down with the co-evolution of pathogen,threatening the future of crucif...Soil-borne pathogens,e.g.,Plasmodiophora brassicae,causes devastating clubroot disease,and existing identified resistance(R)genes has been broken down with the co-evolution of pathogen,threatening the future of cruciferous crops.Thus,there is a dire need to identify new R genes for developing clubroot-resistant crops.Recently,Wang et al.,2023 have reported a new R gene,WeiTsing,that confers complete resistance to Plasmodiophora brassicae,providing an opportunity to deliver broad-spectrum,durable clubroot-resistant crop varieties.展开更多
文摘BACKGROUND End-stage liver disease is a global health complication with high prevalence and limited treatment options.Cell-based therapies using mesenchymal stem cells(MSCs)emerged as an alternative approach to support hepatic regeneration.In vitro preconditioning strategies have been employed to strengthen the regenerative and differentiation potential of MSCs towards hepatic lineage.Chemical compounds of the triterpene class;glycyrrhizic acid(GA)and 18β-glycyrrhetinic acid(GT)possess diverse therapeutic properties including hepatoprotection and anti-fibrosis characteristics.They are capable of modulating several signaling pathways that are crucial in hepatic regeneration.Preconditioning with hepato-protective triterpenes may stimulate MSC fate transition towards hepatocytes.AIM To explore the effect of GA and GT on hepatic differentiation of human umbilical cord-MSCs(hUC-MSCs).METHODS hUC-MSCs were isolated and characterized phenotypically by flow cytometry and immunocytochemistry for the expression of MSC-associated surface molecules.Isolated cells were treated with GA,GT,and their combination for 24 h and then analyzed at three time points;day 7,14,and 21.qRT-PCR was performed for the expression of hepatic genes.Expression of hepatic proteins was analyzed by immunocytochemistry at day 21.Periodic acid Schiff staining was performed to determine the functional ability of treated cells.RESULTS The fusiform-shaped morphology of MSCs in the treatment groups in comparison with the untreated control,eventually progressed towards the polygonal morphology of hepatocytes with the passage of time.The temporal transcriptional profile of preconditioned MSCs displayed significant expression of hepatic genes with increasing time of differentiation.Preconditioned cells showed positive expression of hepatocyte-specific proteins.The results were further corroborated by positive periodic acid Schiff staining,indicating the presence of glycogen in their cytoplasm.Moreover,bi-nucleated cells,which is the typical feature of hepatocytes,were also seen in the preconditioned cells.CONCLUSION Preconditioning with glycyrrhizic acid,18β-glycyrrhetinic acid and their combination,successfully differentiates hUC-MSCs into hepatic-like cells.These MSCs may serve as a better therapeutic option for degenerative liver diseases in future.
基金supported by grants from National Science Fund of China (Nos. 31572289, 31872239 and 81630091)International S&T Cooperation Program of China (No. S2016G3110)+3 种基金Hubei Science Fund (Nos. 2015CFA042 and 2016CFA018)China-Kazakhstan Cooperation Program (No. CK-07-09)Fundamental Research Funds for the Central Universities in China (Nos. 2042017kf0242 and 2042017kf0199)financial support from Higher Education Commission (HEC) of Pakistan
文摘Dengue virus(DENV) and Zika virus(ZIKV) have spread throughout many countries in the developing world and infect millions of people every year, causing severe harm to human health and the economy. Unfortunately, there are few effective vaccines and therapies available against these viruses. Therefore, the discovery of new antiviral agents is critical.Herein, a scorpion venom peptide(Smp76) characterized from Scorpio maurus palmatus was successfully expressed and purified in Escherichia coli BL21(DE3). The recombinant Smp76(rSmp76) was found to effectively inhibit DENV and ZIKV infections in a dose-dependent manner in both cultured cell lines and primary mouse macrophages. Interestingly,rSmp76 did not inactivate the viral particles directly but suppressed the established viral infection, similar to the effect of interferon(IFN)-b. Mechanistically, rSmp76 was revealed to upregulate the expression of IFN-b by activating interferon regulatory transcription factor 3(IRF3) phosphorylation, enhancing the type-Ⅰ IFN response and inhibiting viral infection.This mechanism is significantly different from traditional virucidal antimicrobial peptides(AMPs). Overall, the scorpion venom peptide Smp76 is a potential new antiviral agent with a unique mechanism involving type-Ⅰ IFN responses,demonstrating that natural AMPs can enhance immunity by functioning as immunomodulators.
文摘The title compounds 3-（3,5-bis（trifluoromethyl）phenyl）quinoline （1） and 3-（4- fluoro-3-methylphenyl）quinoline （2） were synthesized through Suzuki-Miyaura Cross coupling reaction of 3-bromoquinoloine with aryl boronic acids. The title compounds were characterized by single-crystal X-ray diffraction, 1H NMR, 13C NMR, El-MS, elemental analysis and IR. The crystals of 3-（3,5-bis（trifluoromethyl）phenyl）quinoline （C17H9F6N, Mr = 341.25） belongs to the monoclinic system, space group P21n, a = 12.3072（13）, b = 4.9378（6）, c = 24.493（2） A, V= 1473.1（3） A3, Z = 4, Dc = 1.539 Mg m-3, 2 - 0.71073A, μ = 0.144 mm^-1, F（000） = 688, the final R = 0.0715 and wR = 0.1873 for 1875 obserwed reflections with I 〉 2σ（I） and the crystal of 3-（4-fluoro-3- methylphenyl）quinoline （C16H12FN, Mr= 237.27） belongs to the orthorhombic system, space group Pca21, a = 23.794（2）, b = 3.9094（3）, c = 25.669（2） A, V = 2387.7（4） A3, Z = 8, D, = 1.320 Mg m-3, 2 = 0.71073 A, μ = 0.088 mm-1, F（000） = 992, the final R = 0.0534 and wR = 0.1188 for 2270 observed reflections with I 〉 2σ（I）.
文摘BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tissue.Cardiac tissue engineering using biomaterial scaffolds combined with stem cells and bioactive molecules could be a highly promising approach for cardiac repair.Use of biomaterials can provide suitable microenvironment to the cells and can solve cell engraftment problems associated with cell transplantation alone.Mesenchymal stem cells(MSCs)are potential candidates in cardiac tissue engineering because of their multilineage differentiation potential and ease of isolation.Use of DNA methyl transferase inhibitor,such as zebularine,in combination with three-dimensional(3D)scaffold can promote efficient MSC differentiation into cardiac lineage,as epigenetic modifications play a fundamental role in determining cell fate and lineage specific gene expression.AIM To investigate the role of collagen scaffold and zebularine in the differentiation of rat bone marrow(BM)-MSCs and their subsequent in vivo effects.METHODS MSCs were isolated from rat BM and characterized morphologically,immunophenotypically and by multilineage differentiation potential.MSCs were seeded in collagen scaffold and treated with 3μmol/L zebularine in three different ways.Cytotoxicity analysis was done and cardiac differentiation was analyzed at the gene and protein levels.Treated and untreated MSC-seeded scaffolds were transplanted in the rat myocardial infarction(MI)model and cardiac function was assessed by echocardiography.Cell tracking was performed by DiI dye labeling,while regeneration and neovascularization were evaluated by histological and immunohistochemical analysis,respectively.RESULTS MSCs were successfully isolated and seeded in collagen scaffold.Cytotoxicity analysis revealed that zebularine was not cytotoxic in any of the treatment groups.Cardiac differentiation analysis showed more pronounced results in the type 3 treatment group which was subsequently chosen for the transplantation in the in vivo MI model.Significant improvement in cardiac function was observed in the zebularine treated MSC-seeded scaffold group as compared to the MI control.Histological analysis also showed reduction in fibrotic scar,improvement in left ventricular wall thickness and preservation of ventricular remodeling in the zebularine treated MSC-seeded scaffold group.Immunohistochemical analysis revealed significant expression of cardiac proteins in DiI labeled transplanted cells and a significant increase in the number of blood vessels in the zebularine treated MSC-seeded collagen scaffold transplanted group.CONCLUSION Combination of 3D collagen scaffold and zebularine treatment enhances cardiac differentiation potential of MSCs,improves cell engraftment at the infarcted region,reduces infarct size and improves cardiac function.
文摘A novel {[bis（pyridine-κN）bis（3,5-dinitrosalicylato κ-O,O＇）Zn（Ⅱ）][bis（pyridine-κN）Zn（Ⅱ）]}（C_（34）H_（24）N_8O_（14）Zn_2） was synthesized by a self-assemble method at room temperature. The molecular structure was determined by single-crystal X-ray analysis. The compound crystallizes in the monoclinic system, space group P2_1/n with a = 12.2156, b = 13.5696, c = 22.5602 A, β = 90.061o, Z = 4 and V = 3739.6（3）A^3. The new 1D binuclear coordination polymer {[bis（py-κN）bis（3,5-dinitrosal κ-O,O′） Zn（Ⅱ）][bis（py-κN）Zn（Ⅱ）]} resulted from two different types of moieties. The polymer [bis（py-κN）bis（3,5-dinitrosal κ-O,O′）Zn（Ⅱ）] unit is connected with [bis（py-κN） Zn（Ⅱ）] by zigzag topology. One zinc（Ⅱ） cation has a six-fold coordination environment, in which the metal atom is connected with four oxygen atoms of two 3,5-dinitrosalicylic acids to form equatorial bonds and two nitrogen atoms of pyridine to generate the axial bonds. Other four-fold nucleus contain two Zn-O bonds from different 3,5-dinitrosalicylic acids and two bonds with the Natom of pyridine. Antimicrobial assay results indicated that the compound showed moderate activities against different bacterial and fungal strains.
文摘The oxidations of D-fructose and D-lactose were monitored spectrophotometrically by potassium permanganate in acidic medium at λmax 545 nm. Reaction demonstrated that the two oxidative species of permanganate were involved in an acidic oxidation of the sugars. It was established that respective acids of sugars as well as arabinonic and formic acid were the oxidation products. Respective acids of sugars were the results of reactive oxygen species of permanganate ions in acidic conditions while arabinonic and formic acids due to the cleavage of C__C bond through MnO-4 species. It was first order kinetics with respect to [MnO-4 ], [fructose], [lactose] and [H+]. Hg was used to accelerate the slow oxidation of lactose. Effect of varying salt electrolyte concentration was insignificant showing that the molecular species was involved in the rate determining step. Formic and arabinonic acids and respective acids were analyzed through spot and spectroscopic studies respectively. Reaction was monitored at different temperatures and thermodynamics activation parameters were determined. A mechanism consistent with kinetic studies, spectral evidences, stoichiometry of the reactions and product analysis has been proposed for the oxidation of fructose and lactose in absence and presence of catalyst respectively.
文摘Exposure to toxic chemicals appears to be one of the major factors in the onset of Schizophrenia. Present study was designed to find out the association of socio-economic, clinical and heavy metals such as chromium (Cr), lead (Pb) copper (Cu), zinc (Zn), iron (Fe), manganese (Mn) selenium (Se) and arsenic (As) as the principle environmental factors that appear to impact schizophrenic condition in Pakistani population. In this study we have tried to expose some factors such as drug abuse, marital status, education, monthly income that could be related to the disease. These parameters were not investigated before in Pakistani subjects. A self-made questionnaire was developed to collect and record the history of patient’s social and economical status. The level of transition metals in the whole blood was also measured by using Inductive couple plasma optical emission spectroscopy (ICP-OES). Present study has found higher levels of Cr, Pb, Zn, Se, As and Cu and lower levels of Fe and Mn in the blood of newly diagnosed (ND) patients when compared to the controls. While comparing ND with the patients who were on medication (Old Diagnosed) we, found lower level of these metals except for copper in ND. However no significant differences were observed between any trace metal levels between the studied groups. The survey concludes that economic status, marital status and illegal drugs are significantly associated with schizophrenia. Pakistani men who use cannabis are significantly higher in numbers when compared to women in acquiring the psychiatric symptoms.
文摘In present work chitosan functionalized magnetic nanoparticles (CMNPs) were successfully prepared and investigated for the removal of Reactive Orange 107 dye (RO 107) from water. The chitosan was extracted from shrimp shells (Penaeus merguiensis) and was characterized by solubility test and fourier transform infrared spectroscopy (FTIR). Degree of deacetylation of chitosan was examined by 1H-NMR and potentiometric titration method. Thereafter, the chitosan was used for synthesis of CMNPs. The synthesized CMNPs were characterized by FTIR, scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), thermal gravimetric analysis (TGA) and atomic force microscopy (AFM). Effects of various variables such as contact time, pH, stirring speed, adsorbent dosage, temperature, and concentration of electrolyte on extraction efficiency were evaluated. Freundlich isotherm model fits better that shows the removal of RO 107 with CMNPs by multilayer adsorption behaviour. Furthermore, kinetic study showed that adsorption process followed pseudo-second order kinetic model regulated by chemisorption. Thermodynamic analysis explained that adsorption of RO 107 onto CMNPs was endothermic as well as spontaneous. The developed CNMPs were applied to environmental remediation of spiked RO 107 treated waste water samples with 96.20% removal potential, hence, offered an effective sorbent for removal of RO 107 contaminated water samples.
文摘Introduction:Past incidences have been recorded relating to mishandling of hazardous material either due to insufficient knowledge or inappropriate equipment resulting in the indirect transfer of infectious agents.It is necessary to identify gaps that inhibit proper protection of healthcare professionals from being inadvertently exposed to biological risks.Methods:A cross sectional study was conducted at multiple laboratories across Karachi,Pakistan from January to August 2018.Descriptive questionnaire was used to record data about types and usage of Biological Safety Cabinets(BSCs),along with policies and practices adapted for its certification.Results:A total of 30 laboratories were visited which included Clinical/Biomedical,University hospital,R&D and animal laboratories.Among these 60%always used BSCs,30%periodically used BSCs while 10%did not have any BSCs.Among these facilities 63.6%had BSC class II-A2,39.9%had BSC class II-B2,4.5%had BSC class III and only 0.9%had BSC class I cabinet.No protocols for field certification of BSCs were available.Conclusion:Establishment of biosafety training sessions,implementation and development of protocol for field certification for proper and safe use of BSCs on a local basis accompanied by continuous monitoring is required,for creating a safe environment for all laboratory staff.
文摘Soil-borne pathogens,e.g.,Plasmodiophora brassicae,causes devastating clubroot disease,and existing identified resistance(R)genes has been broken down with the co-evolution of pathogen,threatening the future of cruciferous crops.Thus,there is a dire need to identify new R genes for developing clubroot-resistant crops.Recently,Wang et al.,2023 have reported a new R gene,WeiTsing,that confers complete resistance to Plasmodiophora brassicae,providing an opportunity to deliver broad-spectrum,durable clubroot-resistant crop varieties.
