The effects of rotation and gravity on an electro-magneto-thermoelastic medium with diffusion and voids in a generalized thermoplastic half-space are studied by using the Lord-Shulman (L-S) model and the dual-phase-la...The effects of rotation and gravity on an electro-magneto-thermoelastic medium with diffusion and voids in a generalized thermoplastic half-space are studied by using the Lord-Shulman (L-S) model and the dual-phase-lag (DPL) model. The analytical solutions for the displacements, stresses, temperature, diffusion concentration, and volume fraction field with different values of the magnetic field, the rotation, the gravity, and the initial stress are obtained and portrayed graphically. The results indicate that the effects of gravity, rotation, voids, diffusion, initial stress, and electromagnetic field are very pronounced on the physical properties of the material.展开更多
AIM: To test whether oral L-81 treatment could im-prove the condition of mice with diabetes and to investigate how L-81 regulates microsomal triglyceride transfer protein (MTP) activity in the liver. METHODS: Genetica...AIM: To test whether oral L-81 treatment could im-prove the condition of mice with diabetes and to investigate how L-81 regulates microsomal triglyceride transfer protein (MTP) activity in the liver. METHODS: Genetically diabetic (db/db) mice were fed on chow supplemented with or without L-81 for 4 wk. The body weight, plasma glucose level, plasma lipid profile, and adipocyte volume of the db/db mice were assessed after treatment. Toxicity of L-81 was also evaluated. To understand the molecular mecha-nism, HepG2 cells were treated with L-81 and the effects on apolipoprotein B (apoB) secretion and mRNA level of the MTP gene were assessed.RESULTS: Treatment of db/db mice with L-81 sig-nificantly reduced and nearly normalized their body weight, hyperphagia and polydipsia. L-81 also markedly decreased the fasting plasma glucose level, improved glucose tolerance, and attenuated the elevated levels of plasma cholesterol and triglyceride. At the effective dosage, little toxicity was observed. Treatment of HepG2 cells with L-81 not only inhibited apoB secretion, but also signif icantly decreased the mRNA level of the MTP gene. Similar to the action of insulin, L-81 exerted its effect on the MTP promoter. CONCLUSION: L-81 represents a promising candidate in the development of a selective insulin-mimetic mol-ecule and an anti-diabetic agent.展开更多
This study investigated the effects of the L-17 compound of the group of substituted 5R1, 6H2-1,3,4- thiadiazine-2-amines on the possibility of inflammatory reaction evolvement correction in experimental acute pancrea...This study investigated the effects of the L-17 compound of the group of substituted 5R1, 6H2-1,3,4- thiadiazine-2-amines on the possibility of inflammatory reaction evolvement correction in experimental acute pancreatitis. The study was based upon recent clinical and experimental work which demonstrated the role of local and systemic inflammatory reactions in pancreatonecrosis. Pancreatonecrosis modeling in rats was performed in accordance with the author’s modification of ligation model of acute pancreatitis. The biochemical and hematological analysis were performed in all groups at day 1. For microscopic analysis, five histological slices of each animal were analyzed. The main group, consisting of 15 animals with the average body weight 223 g each, got intraperitoneal injection of L-17 compound, dozed 40 mg/kg in an hour after surgery of pancreatitis formation. Later on, a 40 mg/kg doze of L-17 compound was repeatedly injected as often as once every 24 hours. Already during the 1st day of the experiment, no leucopenia was observed and the signs of proliferative inflammation were detected. Later, at the background of L-17 compound introduction (5th day of the experiment) the necrosis area got surrounded by demarcation bank, and further on (by the 7th day) had been entirely replaced by granulation tissue. Thus, the application of L-17 compound in experimental acute pan-creatitis results in replacement of destructive purulent inflammation by exudative-proliferative one, prevents lympho- and monocytopenia development, minimizes amylase and pancreatic ferments level during the first day of development of the disease and cuts down the lethality rate as result of pancreatonecrosis complications twofold.展开更多
BACKGROUND： Parkinson＇s disease （PD） is a common, age-dependent degenerative neurological disorder impairing motor control function and cognition. A key pathology of PD is a degeneration of the nigrostriatal dopam...BACKGROUND： Parkinson＇s disease （PD） is a common, age-dependent degenerative neurological disorder impairing motor control function and cognition. A key pathology of PD is a degeneration of the nigrostriatal dopamine system, leading to a severe dopamine denervation in the striatum and dynsfunction of the striatal neural circuits. OBJECTIVE： To better understand the pathophysiology of the nigrostriatal dopamine denervation and to discover better treatments, animal PD models are needed. METHODS： The authors＇ original research on the transcription factor Pitx3 null mutant mice and the relevant literature were reviewed. RESULTS： An important feature of an animal PD model is the severe, PD-like nigrostriatal dopamine denervation. This feature is provided in the transcription factor Pitx3 null mutant mice. These mice have a severe and bilateral nigral dopamine neuron loss and dopamine denervation in the dorsal striatum, while the dopamine neuron loss in the ventral tegmental area and dopamine denervation in the ventral striatum are moderate, creating a dorsal-ventral dopamine loss gradient and mimicking the dopamine denervation pattern in PD. Pitx3 null mice show motor function deficits in the balance beam and pole tests and these deficits are reversed by L-3,4-dihydroxyphenylalanine （L-dopa）. These mice also show impaired cognitive functions as indicated by reduced motor learning and avoidance memory. L-dopa, D 1 agonists and, to a lesser extent, D2 agonists, induce normal horizontal movements （walking） and also dyskinesia-like movements consisting of vertical body trunk movements and waving paw movements. CONCLUSIONS： The easy-to-maintain Pitx3 null mice with an autogenic, consistent and gradient dopamine denervation are a convenient and suitable mouse model to study the consequences of dopamine loss in PD and to test dopaminergic replacement therapies for PD.展开更多
文摘The effects of rotation and gravity on an electro-magneto-thermoelastic medium with diffusion and voids in a generalized thermoplastic half-space are studied by using the Lord-Shulman (L-S) model and the dual-phase-lag (DPL) model. The analytical solutions for the displacements, stresses, temperature, diffusion concentration, and volume fraction field with different values of the magnetic field, the rotation, the gravity, and the initial stress are obtained and portrayed graphically. The results indicate that the effects of gravity, rotation, voids, diffusion, initial stress, and electromagnetic field are very pronounced on the physical properties of the material.
基金Supported by The Area of Excellence scheme of University Grants Committeethe Research Grant Council Grant, HKU 7642/05M to MCL, from Hong Kong
文摘AIM: To test whether oral L-81 treatment could im-prove the condition of mice with diabetes and to investigate how L-81 regulates microsomal triglyceride transfer protein (MTP) activity in the liver. METHODS: Genetically diabetic (db/db) mice were fed on chow supplemented with or without L-81 for 4 wk. The body weight, plasma glucose level, plasma lipid profile, and adipocyte volume of the db/db mice were assessed after treatment. Toxicity of L-81 was also evaluated. To understand the molecular mecha-nism, HepG2 cells were treated with L-81 and the effects on apolipoprotein B (apoB) secretion and mRNA level of the MTP gene were assessed.RESULTS: Treatment of db/db mice with L-81 sig-nificantly reduced and nearly normalized their body weight, hyperphagia and polydipsia. L-81 also markedly decreased the fasting plasma glucose level, improved glucose tolerance, and attenuated the elevated levels of plasma cholesterol and triglyceride. At the effective dosage, little toxicity was observed. Treatment of HepG2 cells with L-81 not only inhibited apoB secretion, but also signif icantly decreased the mRNA level of the MTP gene. Similar to the action of insulin, L-81 exerted its effect on the MTP promoter. CONCLUSION: L-81 represents a promising candidate in the development of a selective insulin-mimetic mol-ecule and an anti-diabetic agent.
文摘This study investigated the effects of the L-17 compound of the group of substituted 5R1, 6H2-1,3,4- thiadiazine-2-amines on the possibility of inflammatory reaction evolvement correction in experimental acute pancreatitis. The study was based upon recent clinical and experimental work which demonstrated the role of local and systemic inflammatory reactions in pancreatonecrosis. Pancreatonecrosis modeling in rats was performed in accordance with the author’s modification of ligation model of acute pancreatitis. The biochemical and hematological analysis were performed in all groups at day 1. For microscopic analysis, five histological slices of each animal were analyzed. The main group, consisting of 15 animals with the average body weight 223 g each, got intraperitoneal injection of L-17 compound, dozed 40 mg/kg in an hour after surgery of pancreatitis formation. Later on, a 40 mg/kg doze of L-17 compound was repeatedly injected as often as once every 24 hours. Already during the 1st day of the experiment, no leucopenia was observed and the signs of proliferative inflammation were detected. Later, at the background of L-17 compound introduction (5th day of the experiment) the necrosis area got surrounded by demarcation bank, and further on (by the 7th day) had been entirely replaced by granulation tissue. Thus, the application of L-17 compound in experimental acute pan-creatitis results in replacement of destructive purulent inflammation by exudative-proliferative one, prevents lympho- and monocytopenia development, minimizes amylase and pancreatic ferments level during the first day of development of the disease and cuts down the lethality rate as result of pancreatonecrosis complications twofold.
文摘BACKGROUND： Parkinson＇s disease （PD） is a common, age-dependent degenerative neurological disorder impairing motor control function and cognition. A key pathology of PD is a degeneration of the nigrostriatal dopamine system, leading to a severe dopamine denervation in the striatum and dynsfunction of the striatal neural circuits. OBJECTIVE： To better understand the pathophysiology of the nigrostriatal dopamine denervation and to discover better treatments, animal PD models are needed. METHODS： The authors＇ original research on the transcription factor Pitx3 null mutant mice and the relevant literature were reviewed. RESULTS： An important feature of an animal PD model is the severe, PD-like nigrostriatal dopamine denervation. This feature is provided in the transcription factor Pitx3 null mutant mice. These mice have a severe and bilateral nigral dopamine neuron loss and dopamine denervation in the dorsal striatum, while the dopamine neuron loss in the ventral tegmental area and dopamine denervation in the ventral striatum are moderate, creating a dorsal-ventral dopamine loss gradient and mimicking the dopamine denervation pattern in PD. Pitx3 null mice show motor function deficits in the balance beam and pole tests and these deficits are reversed by L-3,4-dihydroxyphenylalanine （L-dopa）. These mice also show impaired cognitive functions as indicated by reduced motor learning and avoidance memory. L-dopa, D 1 agonists and, to a lesser extent, D2 agonists, induce normal horizontal movements （walking） and also dyskinesia-like movements consisting of vertical body trunk movements and waving paw movements. CONCLUSIONS： The easy-to-maintain Pitx3 null mice with an autogenic, consistent and gradient dopamine denervation are a convenient and suitable mouse model to study the consequences of dopamine loss in PD and to test dopaminergic replacement therapies for PD.
