We discuss the equivalent form of the Ldvy-Leblond equation such that the nilpotent matrices are two-dimensional. We show that this equation can be obtained in the non-relativistic limit of the (2+1)-dimensional Di...We discuss the equivalent form of the Ldvy-Leblond equation such that the nilpotent matrices are two-dimensional. We show that this equation can be obtained in the non-relativistic limit of the (2+1)-dimensional Dirac equation. Phrthermore, we analyze the case with four-dimensional matrices, propose a Hamiltonian for the equation in (3+1) dimensions, and solve it for a Coulomb potential The quantized energy levels for the hydrogen atom are obtained, and the result is consistent with the non-relativistic quantum mechanics.展开更多
Objective Cholera caused by Vibrio cholerae biotype eltor (EVC) is an endemic disease, subsiding in winter and reappearing in spring and summer Investigating the state of EVC during the intermittent time is of ...Objective Cholera caused by Vibrio cholerae biotype eltor (EVC) is an endemic disease, subsiding in winter and reappearing in spring and summer Investigating the state of EVC during the intermittent time is of crucial importance in controlling this disease Methods Different factors mimicking the internal and external environmental conditions of the host, including human and fish bile, bacterial phages and antibiotics were used experimentally to induce variation in EVC EVC variants were isolated from the stool of diarrhea patients and river water in old endemic areas during the winter The variants obtained were tested with gene probe hybridization, DNA restriction enzyme mapping, immunoenzyme staining and animal passaging Results Due to the loss of cell walls, 3 kinds of EVC variants were obtained during induction: the L form variant, with a complete loss of cell walls; the nonagglutinating variants, with the loss of surface O antigen; the phage resistant variants, with the loss of phage receptors Similar variants were found in field isolation This variation was proved to be phenotypic, with no change in genetic material: it was reversible and appeared in a seasonal pattern, which coincided with the endemicity of this disease Passage in animal enhanced this reversion In compensation for the loss of cell walls, cell membranes were greatly thickened, increasing the ability of the variants to survive during the unfavorable winter conditions Conclusions EVC varied in a seasonal pattern, coincident with the endemicity of this disease The compensatory thickening of the cell membranes protects the EVC variants to survive the winter展开更多
Background:Excessive drinkers(ED)and patients with alcoholic liver disease(ALD)are several times more susceptible to bacterial and viral infections and have a decrease in antibody responses to vaccinations.Follicular ...Background:Excessive drinkers(ED)and patients with alcoholic liver disease(ALD)are several times more susceptible to bacterial and viral infections and have a decrease in antibody responses to vaccinations.Follicular helper T(TFH)cells are essential to select B cells in the germinal center and to produce antibodies.TFH cells express both a membrane-associated and a soluble form of CD40 ligand(sCD40L),in which the latter form is released to circulation upon T cell activation.The effect of alcohol on TFH cells has not been studied.Objectives:The goals of this study are to determine the levels of TFH and T helper 1(Th1)cells in ED and those with alcoholic cirrhosis(AC)when compared to healthy controls and to determine the prognostic significance of sCD40L in a cohort of patients with AC.Methods:Controls,ED,and those with AC were enrolled.Baseline demographic,laboratory tests,and peripheral blood mononuclear cells(PBMCs)were isolated and assessed via flow cytometry for TFH cells.In vitro study was performed to determine the ability of PBMCs to secrete interferon(IFN)-ɣupon stimulation.Serum sCD40L was also determined and its prognostic significance was tested in a cohort of AC patients.Results:The levels of circulating TFH(cTFH)cells were significantly lower in peripheral blood of subjects with ED and AC compared to controls(P<0.05).IFN-ɣsecretion from PBMCs upon stimulation was also lower in ED and those with cirrhosis.Serum sCD40L was significantly lower in ED and AC when compared to that in controls(P<0.0005).Its level was an independent predictor of mortality.Conclusions:Patients with AC had significantly lower level of cTFH and sCD40L.The level of sCD40L was an independent predictor of mortality in these patients.展开更多
文摘We discuss the equivalent form of the Ldvy-Leblond equation such that the nilpotent matrices are two-dimensional. We show that this equation can be obtained in the non-relativistic limit of the (2+1)-dimensional Dirac equation. Phrthermore, we analyze the case with four-dimensional matrices, propose a Hamiltonian for the equation in (3+1) dimensions, and solve it for a Coulomb potential The quantized energy levels for the hydrogen atom are obtained, and the result is consistent with the non-relativistic quantum mechanics.
文摘Objective Cholera caused by Vibrio cholerae biotype eltor (EVC) is an endemic disease, subsiding in winter and reappearing in spring and summer Investigating the state of EVC during the intermittent time is of crucial importance in controlling this disease Methods Different factors mimicking the internal and external environmental conditions of the host, including human and fish bile, bacterial phages and antibiotics were used experimentally to induce variation in EVC EVC variants were isolated from the stool of diarrhea patients and river water in old endemic areas during the winter The variants obtained were tested with gene probe hybridization, DNA restriction enzyme mapping, immunoenzyme staining and animal passaging Results Due to the loss of cell walls, 3 kinds of EVC variants were obtained during induction: the L form variant, with a complete loss of cell walls; the nonagglutinating variants, with the loss of surface O antigen; the phage resistant variants, with the loss of phage receptors Similar variants were found in field isolation This variation was proved to be phenotypic, with no change in genetic material: it was reversible and appeared in a seasonal pattern, which coincided with the endemicity of this disease Passage in animal enhanced this reversion In compensation for the loss of cell walls, cell membranes were greatly thickened, increasing the ability of the variants to survive during the unfavorable winter conditions Conclusions EVC varied in a seasonal pattern, coincident with the endemicity of this disease The compensatory thickening of the cell membranes protects the EVC variants to survive the winter
基金This work was supported by VA Merit Award 1I01BX002634,the NIH R21AA022482,R01DK080440,R01DK104656,R01ES025909,R21CA191507,and P30 DK34989(to L.Wang)VA Merit Award 1I01CX000361,NIH U01AA021840,NIH R01 DK107682,NIH R01 AA025208,US DOD W81XWH-12-1-0497(to S.Liangpunsakul),and NIH R21AA024935-01(to L.Wang and S.Liangpunsakul),and NIH R56 AI112398(to A.L.Dent).
文摘Background:Excessive drinkers(ED)and patients with alcoholic liver disease(ALD)are several times more susceptible to bacterial and viral infections and have a decrease in antibody responses to vaccinations.Follicular helper T(TFH)cells are essential to select B cells in the germinal center and to produce antibodies.TFH cells express both a membrane-associated and a soluble form of CD40 ligand(sCD40L),in which the latter form is released to circulation upon T cell activation.The effect of alcohol on TFH cells has not been studied.Objectives:The goals of this study are to determine the levels of TFH and T helper 1(Th1)cells in ED and those with alcoholic cirrhosis(AC)when compared to healthy controls and to determine the prognostic significance of sCD40L in a cohort of patients with AC.Methods:Controls,ED,and those with AC were enrolled.Baseline demographic,laboratory tests,and peripheral blood mononuclear cells(PBMCs)were isolated and assessed via flow cytometry for TFH cells.In vitro study was performed to determine the ability of PBMCs to secrete interferon(IFN)-ɣupon stimulation.Serum sCD40L was also determined and its prognostic significance was tested in a cohort of AC patients.Results:The levels of circulating TFH(cTFH)cells were significantly lower in peripheral blood of subjects with ED and AC compared to controls(P<0.05).IFN-ɣsecretion from PBMCs upon stimulation was also lower in ED and those with cirrhosis.Serum sCD40L was significantly lower in ED and AC when compared to that in controls(P<0.0005).Its level was an independent predictor of mortality.Conclusions:Patients with AC had significantly lower level of cTFH and sCD40L.The level of sCD40L was an independent predictor of mortality in these patients.