AIM: To evaluate whether pyrrolidine dithiocarbamate (PDTC), an enhancer of HO production, attenuates intestinal IR injury. METHODS: Eighteen male rats were randomly allocated into three groups: (a) sham; (b)...AIM: To evaluate whether pyrrolidine dithiocarbamate (PDTC), an enhancer of HO production, attenuates intestinal IR injury. METHODS: Eighteen male rats were randomly allocated into three groups: (a) sham; (b) IR, consisting of 30 min of intestinal ischemia, followed by 2-h period of reperfusion; and (c) PDTC treatment before IR. Intestinal microvascular perfusion (IMP) was monitored continuously by laser Doppler flowmetry. At the end of the reperfusion, serum samples for lactate dehydrogenase (LDH) levels and biopsies of ileum were obtained. HO activity in the ileum was assessed at the end of the reperfusion period. RESULTS: At the end of the reperfusion in the IR group, IMP recovered partially to 42.5% of baseline (P〈0.05 vs sham), whereas PDTC improved IMP to 67.3% of baseline (P〈0.01 vs IR). There was a twofold increase in HO activity in PDTC group (2 062.66±106.11) as compared to IR (842.3±85.12) (P〈0.001). LDH was significantly reduced (P〈0.001) in PDTC group (585.6±102.4) as compared to IR group (1 973.8±306.5). Histological examination showed that the ileal mucosa was significantly less injured in PDTC group as compared with IR group. CONCLUSION: Our study demonstrates that PDTC improves the IMP and attenuates IR injury of the intestine possibly via HO production. Additional studies are warranted to evaluate the clinical efficacy of PDTC in the prevention of IR injury of the small intestine.展开更多
The occurrence of massive CD4+ T cell depletion is one of the most prominent characteristics of human immunodeficiency virus type 1 (HIV-1) infection during acute phase, resulting in unrestorable destruction to the im...The occurrence of massive CD4+ T cell depletion is one of the most prominent characteristics of human immunodeficiency virus type 1 (HIV-1) infection during acute phase, resulting in unrestorable destruction to the immune system. The infected host undergoes an asymptomatic period lasting several years with low viral load and ostensibly healthy status, which is presumably due to virus-specific adaptive immune responses. In the absence of therapy, an overwhelming majority of cases develop to AIDS within 8-10 years of latent infection. In this review, we discuss the roles in AIDS pathogenesis played by massive CD4+ T lymphocytes depletion in gut-associated lymphoid tissue (GALT) during acute infection and abnormal immune activation emerging in the later part of chronic phase.展开更多
Abstract Objectives To assess the incidence of tetrahydrobiopterin (BH4)deficiency among patients with hyperphenylalaninemia (HPA) in southern Chinese and evaluate clinical outcome and gene mutations in tetrahydrobi...Abstract Objectives To assess the incidence of tetrahydrobiopterin (BH4)deficiency among patients with hyperphenylalaninemia (HPA) in southern Chinese and evaluate clinical outcome and gene mutations in tetrahydrobiopterin deficient patients.Methods Urinary neopterin (N) and biopterin (B) was analyzed in 87 patients with hyperphenylalaninemia by high-performance liquid chromatography. Further combined loading tests with phenylalanine(Phe) (100*!mg/kg) and tetrahydrobiopterin (BH4) (7.5*!mg/kg) were performed in suspected patients with abnormal urinary pterin profiles. Gene mutation analysis was performed for patients with BH4 deficiency and their parents. BH4 deficient patients were treated with BH4 and neurotransmitter precursors after diagnosis. Blood phenylalanine levels, clinical symptoms and mental development were followed up.Results Eleven patients were diagnosed as having BH4 deficiency caused by 6-pyruvoyl tetrahydropterin synthase (PTPS) deficiency. The incidence of tetrahydrobiopterin (BH4) deficiency among patients with hyperphenylalaninemia (HPA) in southern Chinese was 10%. Combined loading tests with phenylalanine and oral BH4 were done in 4 of 11 patients and their phenylalanine levels were decreased to normal 4-6h after BH4 administration. Four different mutations (P87S, N52S, D96N and G144R) in the PTPS gene were detected in 5 families. Five PTPS-deficient patients were treated with synthetic BH4, neurotransmitter precursors (L-dopa plus carbidopa, and 5-hydroxytryptophan). They had satisfactory physical and mental development after treatment. One patient with partial PTPS deficiency had normal growth and mental development without treatment. Conclusions Our results emphasize that screening for BH4 deficiency should be carried out in all patients with hyperphenylalaninemia in order to minimize the misdiagnosis. Patients with BH4 deficiency should be treated early with BH4 and a combination of neurotransmitter precursors.展开更多
To determine the role of hemoglobin( HB) induced heme oxygenase 1 (HO 1) in injured lungs caused by limb ischemia reperfusion (I/R) in rats. Methods: A rat model of ischemia in the hind limbs was made by clamping the ...To determine the role of hemoglobin( HB) induced heme oxygenase 1 (HO 1) in injured lungs caused by limb ischemia reperfusion (I/R) in rats. Methods: A rat model of ischemia in the hind limbs was made by clamping the infrarenal aorta with a microvascular clip, and lung injury occurre d after reperfusion. To induce the expression of HO 1 in the lungs, Hb was admi nistrated intraperitoneally at 16 hours before reperfusion. Northern blotting an d Western blotting were used to detect the expression of HO 1 in the lungs, and the carboxyhemoglobin (COHb) level in arterial blood was assayed. The effect of h emoglobin (Hb) on the injured lungs after limb I/R was determined by measuring t he changes of lung histology, polymorphonuclear (PMN) count, malondialdehyde (MD A) content and wet to dry weight ratio (W/D). Zinc protoporphyrin (ZnPP), an i nhibitor of HO, was used to determine whether HO 1 was induced by Hb after lun g injury. Results: Hb led to a significant increase in HO 1 mRNA and pro tein expression in the lungs, accompanied by the increase of COHb level in arter ial blood. Compared with the sham controls, the lung PMN count, MDA content and W/D significantly increased at 4 hours after limb I/R, which reversed by th e pretreatment with Hb at 16 hours before reperfusion. ZnPP blocked this protect ive role of Hb in the injured lungs. Conclusions: Hb can induce the lung HO 1 expression, which pla ys an important role in the defense against I/R induced lung injury in rats.展开更多
He defect properties in Sc, Y, Gd, Tb, Dy, Ho, Er and Lu were studied using first-principles calculations based on density functional theory. The results indicate that the formation energy of an interstitial He atom i...He defect properties in Sc, Y, Gd, Tb, Dy, Ho, Er and Lu were studied using first-principles calculations based on density functional theory. The results indicate that the formation energy of an interstitial He atom is smaller than that of a substitutional He atom in all hcp rare-earth metals considered. Furthermore, the tetrahedral interstitial position is more favorable than an octahedral position for He defects. The results are compared with those from bcc and fcc metals.展开更多
文摘英语作业是英语课程的重要组成部分,然而小学英语作业出现了“四缺”现象,即缺失目标定位、缺乏内容深度、缺少层次递进和缺欠多元评价。基于此,文章提出作业设计需遵循整体性、多样性、层次性原则,并以译林版《英语》五年级下册Unit 4 Seeing the doctor为例,指出作业优化设计的策略,即以主题为引领构建单元整体框架,以目标为统整拟定单元课时作业,以素养为导向设计单元情境作业。
文摘AIM: To evaluate whether pyrrolidine dithiocarbamate (PDTC), an enhancer of HO production, attenuates intestinal IR injury. METHODS: Eighteen male rats were randomly allocated into three groups: (a) sham; (b) IR, consisting of 30 min of intestinal ischemia, followed by 2-h period of reperfusion; and (c) PDTC treatment before IR. Intestinal microvascular perfusion (IMP) was monitored continuously by laser Doppler flowmetry. At the end of the reperfusion, serum samples for lactate dehydrogenase (LDH) levels and biopsies of ileum were obtained. HO activity in the ileum was assessed at the end of the reperfusion period. RESULTS: At the end of the reperfusion in the IR group, IMP recovered partially to 42.5% of baseline (P〈0.05 vs sham), whereas PDTC improved IMP to 67.3% of baseline (P〈0.01 vs IR). There was a twofold increase in HO activity in PDTC group (2 062.66±106.11) as compared to IR (842.3±85.12) (P〈0.001). LDH was significantly reduced (P〈0.001) in PDTC group (585.6±102.4) as compared to IR group (1 973.8±306.5). Histological examination showed that the ileal mucosa was significantly less injured in PDTC group as compared with IR group. CONCLUSION: Our study demonstrates that PDTC improves the IMP and attenuates IR injury of the intestine possibly via HO production. Additional studies are warranted to evaluate the clinical efficacy of PDTC in the prevention of IR injury of the small intestine.
文摘The occurrence of massive CD4+ T cell depletion is one of the most prominent characteristics of human immunodeficiency virus type 1 (HIV-1) infection during acute phase, resulting in unrestorable destruction to the immune system. The infected host undergoes an asymptomatic period lasting several years with low viral load and ostensibly healthy status, which is presumably due to virus-specific adaptive immune responses. In the absence of therapy, an overwhelming majority of cases develop to AIDS within 8-10 years of latent infection. In this review, we discuss the roles in AIDS pathogenesis played by massive CD4+ T lymphocytes depletion in gut-associated lymphoid tissue (GALT) during acute infection and abnormal immune activation emerging in the later part of chronic phase.
基金theShanghaiScientificandTechnologyCommittee (No .95 41190 3)
文摘Abstract Objectives To assess the incidence of tetrahydrobiopterin (BH4)deficiency among patients with hyperphenylalaninemia (HPA) in southern Chinese and evaluate clinical outcome and gene mutations in tetrahydrobiopterin deficient patients.Methods Urinary neopterin (N) and biopterin (B) was analyzed in 87 patients with hyperphenylalaninemia by high-performance liquid chromatography. Further combined loading tests with phenylalanine(Phe) (100*!mg/kg) and tetrahydrobiopterin (BH4) (7.5*!mg/kg) were performed in suspected patients with abnormal urinary pterin profiles. Gene mutation analysis was performed for patients with BH4 deficiency and their parents. BH4 deficient patients were treated with BH4 and neurotransmitter precursors after diagnosis. Blood phenylalanine levels, clinical symptoms and mental development were followed up.Results Eleven patients were diagnosed as having BH4 deficiency caused by 6-pyruvoyl tetrahydropterin synthase (PTPS) deficiency. The incidence of tetrahydrobiopterin (BH4) deficiency among patients with hyperphenylalaninemia (HPA) in southern Chinese was 10%. Combined loading tests with phenylalanine and oral BH4 were done in 4 of 11 patients and their phenylalanine levels were decreased to normal 4-6h after BH4 administration. Four different mutations (P87S, N52S, D96N and G144R) in the PTPS gene were detected in 5 families. Five PTPS-deficient patients were treated with synthetic BH4, neurotransmitter precursors (L-dopa plus carbidopa, and 5-hydroxytryptophan). They had satisfactory physical and mental development after treatment. One patient with partial PTPS deficiency had normal growth and mental development without treatment. Conclusions Our results emphasize that screening for BH4 deficiency should be carried out in all patients with hyperphenylalaninemia in order to minimize the misdiagnosis. Patients with BH4 deficiency should be treated early with BH4 and a combination of neurotransmitter precursors.
文摘To determine the role of hemoglobin( HB) induced heme oxygenase 1 (HO 1) in injured lungs caused by limb ischemia reperfusion (I/R) in rats. Methods: A rat model of ischemia in the hind limbs was made by clamping the infrarenal aorta with a microvascular clip, and lung injury occurre d after reperfusion. To induce the expression of HO 1 in the lungs, Hb was admi nistrated intraperitoneally at 16 hours before reperfusion. Northern blotting an d Western blotting were used to detect the expression of HO 1 in the lungs, and the carboxyhemoglobin (COHb) level in arterial blood was assayed. The effect of h emoglobin (Hb) on the injured lungs after limb I/R was determined by measuring t he changes of lung histology, polymorphonuclear (PMN) count, malondialdehyde (MD A) content and wet to dry weight ratio (W/D). Zinc protoporphyrin (ZnPP), an i nhibitor of HO, was used to determine whether HO 1 was induced by Hb after lun g injury. Results: Hb led to a significant increase in HO 1 mRNA and pro tein expression in the lungs, accompanied by the increase of COHb level in arter ial blood. Compared with the sham controls, the lung PMN count, MDA content and W/D significantly increased at 4 hours after limb I/R, which reversed by th e pretreatment with Hb at 16 hours before reperfusion. ZnPP blocked this protect ive role of Hb in the injured lungs. Conclusions: Hb can induce the lung HO 1 expression, which pla ys an important role in the defense against I/R induced lung injury in rats.
基金supported by the National Natural Science Foundation of China (Grant No. 10976007)the Fundamental Research Funds for the Central Universities (Grant No. ZYGX2009J040)+1 种基金the Science and Tech-nology Foundation of China Academy of Engineering Physics (Grant No. 2009A0301015)the US Department of Energy, Office of Fusion En-ergy Science (Grant No. DE-AC06-76RLO 1830)
文摘He defect properties in Sc, Y, Gd, Tb, Dy, Ho, Er and Lu were studied using first-principles calculations based on density functional theory. The results indicate that the formation energy of an interstitial He atom is smaller than that of a substitutional He atom in all hcp rare-earth metals considered. Furthermore, the tetrahedral interstitial position is more favorable than an octahedral position for He defects. The results are compared with those from bcc and fcc metals.