Z-scan technique is an effective tool for measuring the optical nonlinearity of the materials. By using this technique the measurement was made for total protein and albumin. The nonlinear refractive index of the tota...Z-scan technique is an effective tool for measuring the optical nonlinearity of the materials. By using this technique the measurement was made for total protein and albumin. The nonlinear refractive index of the total protein and albumin were found to vary linearly with concentration. Hence by calculating the nonlinear refractive index it is possible to measure their concentration in the sample. The values measured thus are found in equivalence with conventional colorimetric method.展开更多
Cardiac hypertrophy is an independent risk factor for sudden cardiac death in clinical settings and the incidence of sudden cardiac death and ventricular arrhythmias are closely related.The aim of this study was to de...Cardiac hypertrophy is an independent risk factor for sudden cardiac death in clinical settings and the incidence of sudden cardiac death and ventricular arrhythmias are closely related.The aim of this study was to determine the effects of the calmodulin-dependent protein kinase(CaMK) Ⅱ inhibitor,KN-93,on L-type calcium current(I Ca,L) and early after-depolarizations(EADs) in hypertrophic cardiomyocytes.A rabbit model of myocardial hypertrophy was constructed through abdominal aortic coarctation(LVH group).The control group(sham group) received a sham operation,in which the abdominal aortic was dissected but not coarcted.Eight weeks later,the degree of left ventricular hypertrophy(LVH) was evaluated using echocardiography.Individual cardiomyocyte was isolated through collagenase digestion.Action potentials(APs) and I Ca,L were recorded using the perforated patch clamp technique.APs were recorded under current clamp conditions and I Ca,L was recorded under voltage clamp conditions.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were observed under the conditions of low potassium(2 mmol/L),low magnesium(0.25 mmol/L) Tyrode’s solution perfusion,and slow frequency(0.25-0.5 Hz) electrical stimulation.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were also evaluated after treatment with different concentrations of KN-92(KN-92 group) and KN-93(KN-93 group).Eight weeks later,the model was successfully established.Under the conditions of low potassium,low magnesium Tyrode’s solution perfusion,and slow frequency electrical stimulation,the incidence of EADs was 0/12,11/12,10/12,and 5/12 in sham group,LVH group,KN-92 group(0.5 μmol/L),and KN-93 group(0.5 μmol/L),respectively.When the drug concentration was increased to 1 μmol/L in KN-92 group and KN-93 group,the incidence of EADs was 10/12 and 2/12,respectively.At 0 mV,the current density was 6.7±1.0 and 6.3±0.7 PA·PF-1 in LVH group and sham group,respectively(P>0.05,n=12).When the drug concentration was 0.5 μmol/L in KN-92 and KN-93 groups,the peak I Ca,L at 0 mV was decreased by(9.4±2.8)% and(10.5±3.0)% in the hypertrophic cardiomyocytes of the two groups,respectively(P>0.05,n=12).When the drug concentration was increased to 1 μmol/L,the peak I Ca,L values were lowered by(13.4±3.7)% and(40±4.9)%,respectively(P<0.01,n=12).KN-93,a specific inhibitor of CaMKII,can effectively inhibit the occurrence of EADs in hypertrophic cardiomyocytes partially by suppressing I Ca,L,which may be the main action mechanism of KN-93 antagonizing the occurrence of ventricular arrhythmias in hypertrophic myocardium.展开更多
Porcine reproductive and respiratory syndrome virus(PRRSV)GP4 protein was prokaryotically expressed,and used as an antigen to immunize six-week-old BALB/c female mice.With conventional cell fusion method,an anti-PRRSV...Porcine reproductive and respiratory syndrome virus(PRRSV)GP4 protein was prokaryotically expressed,and used as an antigen to immunize six-week-old BALB/c female mice.With conventional cell fusion method,an anti-PRRSV GP4 protein monoclonal antibody(Mab)5F12 was successfully prepared.It was identified as IgG2b subclass and had better stability and specificity,which not only responded with recombinant PRRSV GP4 protein,but also with PRRSV.Phage display technique had varieties of applications,in particular,the identification of key antigen epitopes for the development of therapeutic and diagnostic reagents and vaccines.In this study,Mab-5F12 was used as the target for biopanning a 12-mer phage random peptide library.After four rounds of biopanning,two phage-displayed peptides,named P-A and P-G(AKFEVCSPVVLG and GVNQENMLHFSF)were identified that recognized Mab-5F12 specifically.Sequence analysis showed that one or more of the peptides exhibited partial sequence similarity to the native GP4 protein sequence,which corresponded to 69-80 and 84-95 aa segments of the HP-PRRSV GP4 protein.Furthermore,real-time quantitative RT-PCR and indirect immunofluorescence assay indicated consistently the abilities of P-A and P-G to block viral infection in Marc-145 cells and they could function as antiviral agents for PRRSV.展开更多
Repetitive transcranial magnetic stimulation （rTMS） has been utilized as a therapeutic tool for neurodegenerative disorders including Alzheimer＇s disease. However, the precise mechanisms of its clinical effects rem...Repetitive transcranial magnetic stimulation （rTMS） has been utilized as a therapeutic tool for neurodegenerative disorders including Alzheimer＇s disease. However, the precise mechanisms of its clinical effects remain unknown. β-amyloid （Aβ） exhibits direct neurotoxic effects and is closely related to neuronal degeneration in Alzheimer＇s disease. Therefore, it has been hypothesized that the neuroprotective effects of rTMS are related to the mechanisms of protection against Aβ neurotoxicity. Organotypic hippocampal slices were prepared from 8-day old, Sprague Dawley rats. The tissue slices were exposed to 100 μmol/L Al3142 since day 12 in vitro with and without high-frequency （20 Hz） magnetic stimulation. Magnetic stimulation efficacy was evaluated by measuring neuronal nuclei （NeuN） protein expression and by observing cultures following propidium iodide fluorescence staining and bromodeoxyuridine （BrdU） immunohistochemistry. Lactate dehydrogenase activity was detected in the culture media to evaluate hippocampal neuronal damage. Our results demonstrated that high-frequency magnetic stimulation significantly reversed the reduction of NeuN protein expression because of Aβ1-42 exposure （P 〈 0.05） and significantly reduced the number of damaged cells in the hippocampal slices （P 〈 0.05）. However, lactate dehydrogenase levels and anti-BrdU staining results did not reveal any statistical differences These findings indicate that high-frequency magnetic stimulation might have protective effect on hippocampal neurons from Aβ1-42 neurotoxicity.展开更多
Swelling-activated chloride currents（ICl.swell） are thought to play a role in several physiologic and pathophysiologic processes and thus represent a target for therapeutic approaches. However, the mechanism of ICl....Swelling-activated chloride currents（ICl.swell） are thought to play a role in several physiologic and pathophysiologic processes and thus represent a target for therapeutic approaches. However, the mechanism of ICl.swell regulation remains unclear. In this study, we used the whole-cell patch-clamp technique to examine the role of protein kinase C（PKC） in the regulation of ICl.swell in human atrial myocytes. Atrial myocytes were isolated from the right atrial appendages of patients undergoing coronary artery bypass and enzymatically dissociated. ICl.swell was evoked in hypotonic solution and recorded using the whole-cell patch-clamp technique. The PKC agonist phorbol dibutyrate（PDBu） enhanced ICl.swellin a concentration-dependent manner, which was reversed in isotonic solution and by a chloride current inhibitor, 9-anthracenecarboxylicacid. Furthermore, the PKC inhibitor bis-indolylmaleimide attenuated the effect and 4α-PDBu, an inactive PDBu analog, had no effect on ICl.swell. These results, obtained using the whole-cell patch-clamp technique, demonstrate the ability of PKC to activate ICl,swell in human atrial myocytes. This observation was consistent with a previous study using a single-channel patch-clamp technique, but differed from some findings in other species.展开更多
To study quantitative index of bci-2, P53, Nroliferating cell nuclear antigen (PCNA),ER and PR in breast carcinoma and their correiation and their relatiousbip with prognosis, the ex expression of bcl-2, P53 and PCNA ...To study quantitative index of bci-2, P53, Nroliferating cell nuclear antigen (PCNA),ER and PR in breast carcinoma and their correiation and their relatiousbip with prognosis, the ex expression of bcl-2, P53 and PCNA were studied by immunohistochemical technique. The measurementof ER and PR used enzyme linked affinuity histochemical methods. The quantitative index was analyzed by image technique. All analyses were hased on 60 breast carcinomas. The results were as follows:the more bcl-2 protein, the lower histological graded the longer survival term and the highersurvival rate (P< 0. 05). The quautitative measurement of bcl-2, P53 and PCNA expression were ofvalue in evaluating the degree of differentiation and prognosis in breast carcinoma. The quantitativeand qualitative measurement or p53 protein expression showed a Ⅰwerful evidence in evaluatingprognosis of bcl-2 were more significant in evaluating poor prognosis of breast carcinoma. A relationship between bcl-2 and ER, PR showed a better value for response to endocrine therapy in breastcarcinoma patients.展开更多
Multi-target neural circuit-magnetic stimulation has been clinically shown to improve rehabilitation of lower limb motor function after spinal cord injury. However, the precise underlying mechanism remains unclear. In...Multi-target neural circuit-magnetic stimulation has been clinically shown to improve rehabilitation of lower limb motor function after spinal cord injury. However, the precise underlying mechanism remains unclear. In this study, we performed double-target neural circuit-magnetic stimulation on the left motor cortex and bilateral L5 nerve root for 3 successive weeks in a rat model of incomplete spinal cord injury caused by compression at T10. Results showed that in the injured spinal cord, the expression of the astrocyte marker glial fibrillary acidic protein and inflammatory factors interleukin 1β, interleukin-6, and tumor necrosis factor-α had decreased, whereas that of neuronal survival marker microtubule-associated protein 2 and synaptic plasticity markers postsynaptic densification protein 95 and synaptophysin protein had increased. Additionally, neural signaling of the descending corticospinal tract was markedly improved and rat locomotor function recovered significantly. These findings suggest that double-target neural circuit-magnetic stimulation improves rat motor function by attenuating astrocyte activation, thus providing a theoretical basis for application of double-target neural circuit-magnetic stimulation in the clinical treatment of spinal cord injury.展开更多
文摘Z-scan technique is an effective tool for measuring the optical nonlinearity of the materials. By using this technique the measurement was made for total protein and albumin. The nonlinear refractive index of the total protein and albumin were found to vary linearly with concentration. Hence by calculating the nonlinear refractive index it is possible to measure their concentration in the sample. The values measured thus are found in equivalence with conventional colorimetric method.
基金supported by grants from the Fujian Provincial Natural Science Foundation of China (No. 2008J0075)the Fujian Provincial Science and Technology Project of China(No. 2010Y0011)
文摘Cardiac hypertrophy is an independent risk factor for sudden cardiac death in clinical settings and the incidence of sudden cardiac death and ventricular arrhythmias are closely related.The aim of this study was to determine the effects of the calmodulin-dependent protein kinase(CaMK) Ⅱ inhibitor,KN-93,on L-type calcium current(I Ca,L) and early after-depolarizations(EADs) in hypertrophic cardiomyocytes.A rabbit model of myocardial hypertrophy was constructed through abdominal aortic coarctation(LVH group).The control group(sham group) received a sham operation,in which the abdominal aortic was dissected but not coarcted.Eight weeks later,the degree of left ventricular hypertrophy(LVH) was evaluated using echocardiography.Individual cardiomyocyte was isolated through collagenase digestion.Action potentials(APs) and I Ca,L were recorded using the perforated patch clamp technique.APs were recorded under current clamp conditions and I Ca,L was recorded under voltage clamp conditions.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were observed under the conditions of low potassium(2 mmol/L),low magnesium(0.25 mmol/L) Tyrode’s solution perfusion,and slow frequency(0.25-0.5 Hz) electrical stimulation.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were also evaluated after treatment with different concentrations of KN-92(KN-92 group) and KN-93(KN-93 group).Eight weeks later,the model was successfully established.Under the conditions of low potassium,low magnesium Tyrode’s solution perfusion,and slow frequency electrical stimulation,the incidence of EADs was 0/12,11/12,10/12,and 5/12 in sham group,LVH group,KN-92 group(0.5 μmol/L),and KN-93 group(0.5 μmol/L),respectively.When the drug concentration was increased to 1 μmol/L in KN-92 group and KN-93 group,the incidence of EADs was 10/12 and 2/12,respectively.At 0 mV,the current density was 6.7±1.0 and 6.3±0.7 PA·PF-1 in LVH group and sham group,respectively(P>0.05,n=12).When the drug concentration was 0.5 μmol/L in KN-92 and KN-93 groups,the peak I Ca,L at 0 mV was decreased by(9.4±2.8)% and(10.5±3.0)% in the hypertrophic cardiomyocytes of the two groups,respectively(P>0.05,n=12).When the drug concentration was increased to 1 μmol/L,the peak I Ca,L values were lowered by(13.4±3.7)% and(40±4.9)%,respectively(P<0.01,n=12).KN-93,a specific inhibitor of CaMKII,can effectively inhibit the occurrence of EADs in hypertrophic cardiomyocytes partially by suppressing I Ca,L,which may be the main action mechanism of KN-93 antagonizing the occurrence of ventricular arrhythmias in hypertrophic myocardium.
基金Supported by the National Natural Science Foundation of China(31372438,31200122)
文摘Porcine reproductive and respiratory syndrome virus(PRRSV)GP4 protein was prokaryotically expressed,and used as an antigen to immunize six-week-old BALB/c female mice.With conventional cell fusion method,an anti-PRRSV GP4 protein monoclonal antibody(Mab)5F12 was successfully prepared.It was identified as IgG2b subclass and had better stability and specificity,which not only responded with recombinant PRRSV GP4 protein,but also with PRRSV.Phage display technique had varieties of applications,in particular,the identification of key antigen epitopes for the development of therapeutic and diagnostic reagents and vaccines.In this study,Mab-5F12 was used as the target for biopanning a 12-mer phage random peptide library.After four rounds of biopanning,two phage-displayed peptides,named P-A and P-G(AKFEVCSPVVLG and GVNQENMLHFSF)were identified that recognized Mab-5F12 specifically.Sequence analysis showed that one or more of the peptides exhibited partial sequence similarity to the native GP4 protein sequence,which corresponded to 69-80 and 84-95 aa segments of the HP-PRRSV GP4 protein.Furthermore,real-time quantitative RT-PCR and indirect immunofluorescence assay indicated consistently the abilities of P-A and P-G to block viral infection in Marc-145 cells and they could function as antiviral agents for PRRSV.
文摘Repetitive transcranial magnetic stimulation （rTMS） has been utilized as a therapeutic tool for neurodegenerative disorders including Alzheimer＇s disease. However, the precise mechanisms of its clinical effects remain unknown. β-amyloid （Aβ） exhibits direct neurotoxic effects and is closely related to neuronal degeneration in Alzheimer＇s disease. Therefore, it has been hypothesized that the neuroprotective effects of rTMS are related to the mechanisms of protection against Aβ neurotoxicity. Organotypic hippocampal slices were prepared from 8-day old, Sprague Dawley rats. The tissue slices were exposed to 100 μmol/L Al3142 since day 12 in vitro with and without high-frequency （20 Hz） magnetic stimulation. Magnetic stimulation efficacy was evaluated by measuring neuronal nuclei （NeuN） protein expression and by observing cultures following propidium iodide fluorescence staining and bromodeoxyuridine （BrdU） immunohistochemistry. Lactate dehydrogenase activity was detected in the culture media to evaluate hippocampal neuronal damage. Our results demonstrated that high-frequency magnetic stimulation significantly reversed the reduction of NeuN protein expression because of Aβ1-42 exposure （P 〈 0.05） and significantly reduced the number of damaged cells in the hippocampal slices （P 〈 0.05）. However, lactate dehydrogenase levels and anti-BrdU staining results did not reveal any statistical differences These findings indicate that high-frequency magnetic stimulation might have protective effect on hippocampal neurons from Aβ1-42 neurotoxicity.
基金supported by grants from the Scientific Research Foundation for Returned Scholars,Ministry of Education of China(No.2004-527)the Project on Social Development,Department of Science and Technology of Guizhou Province,China(No.2011-040)
文摘Swelling-activated chloride currents（ICl.swell） are thought to play a role in several physiologic and pathophysiologic processes and thus represent a target for therapeutic approaches. However, the mechanism of ICl.swell regulation remains unclear. In this study, we used the whole-cell patch-clamp technique to examine the role of protein kinase C（PKC） in the regulation of ICl.swell in human atrial myocytes. Atrial myocytes were isolated from the right atrial appendages of patients undergoing coronary artery bypass and enzymatically dissociated. ICl.swell was evoked in hypotonic solution and recorded using the whole-cell patch-clamp technique. The PKC agonist phorbol dibutyrate（PDBu） enhanced ICl.swellin a concentration-dependent manner, which was reversed in isotonic solution and by a chloride current inhibitor, 9-anthracenecarboxylicacid. Furthermore, the PKC inhibitor bis-indolylmaleimide attenuated the effect and 4α-PDBu, an inactive PDBu analog, had no effect on ICl.swell. These results, obtained using the whole-cell patch-clamp technique, demonstrate the ability of PKC to activate ICl,swell in human atrial myocytes. This observation was consistent with a previous study using a single-channel patch-clamp technique, but differed from some findings in other species.
文摘To study quantitative index of bci-2, P53, Nroliferating cell nuclear antigen (PCNA),ER and PR in breast carcinoma and their correiation and their relatiousbip with prognosis, the ex expression of bcl-2, P53 and PCNA were studied by immunohistochemical technique. The measurementof ER and PR used enzyme linked affinuity histochemical methods. The quantitative index was analyzed by image technique. All analyses were hased on 60 breast carcinomas. The results were as follows:the more bcl-2 protein, the lower histological graded the longer survival term and the highersurvival rate (P< 0. 05). The quautitative measurement of bcl-2, P53 and PCNA expression were ofvalue in evaluating the degree of differentiation and prognosis in breast carcinoma. The quantitativeand qualitative measurement or p53 protein expression showed a Ⅰwerful evidence in evaluatingprognosis of bcl-2 were more significant in evaluating poor prognosis of breast carcinoma. A relationship between bcl-2 and ER, PR showed a better value for response to endocrine therapy in breastcarcinoma patients.
基金supported by the National Natural Science Foundation of China,Nos. 81772453 and 81974358 (both to DSX)Shanghai Municipal Key Clinical Specialty Program,No. shslczdzk02701 (to QX)。
文摘Multi-target neural circuit-magnetic stimulation has been clinically shown to improve rehabilitation of lower limb motor function after spinal cord injury. However, the precise underlying mechanism remains unclear. In this study, we performed double-target neural circuit-magnetic stimulation on the left motor cortex and bilateral L5 nerve root for 3 successive weeks in a rat model of incomplete spinal cord injury caused by compression at T10. Results showed that in the injured spinal cord, the expression of the astrocyte marker glial fibrillary acidic protein and inflammatory factors interleukin 1β, interleukin-6, and tumor necrosis factor-α had decreased, whereas that of neuronal survival marker microtubule-associated protein 2 and synaptic plasticity markers postsynaptic densification protein 95 and synaptophysin protein had increased. Additionally, neural signaling of the descending corticospinal tract was markedly improved and rat locomotor function recovered significantly. These findings suggest that double-target neural circuit-magnetic stimulation improves rat motor function by attenuating astrocyte activation, thus providing a theoretical basis for application of double-target neural circuit-magnetic stimulation in the clinical treatment of spinal cord injury.
