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Biomedical subjects

Hong Jiang

Publications and source records attributed to Hong Jiang.

At least 127 records · Page 7Linked to original sources
PubMed2004

Adeno-associated viral vector-mediated ApoE expression in Alzheimer's disease mice: low CNS immune response, long-term expression, and astrocyte specificity.

Recombinant Adenovirus and Adeno-associated virus (AAV) are highly effective vehicles for gene transfer into CNS cells. However, the duration of gene expression and the cytotoxicity to cells are quite different between these viral approaches. We initially investigated these distinctions by stereotaxically injecting both Adenovirus vector and AAV vectors expressing reporter genes into mouse hippocampus. The adenovirus vector induced a pronounced immune response with a marked increase in CD45 and MHC class I protein expression and transgene expression was shorter than six weeks. In contrast, with the AAV vector there was lower expression of CD45 and MHC class I immune activation markers, and longer expression of reporter gene (up to 12 months). To study the roles of human Apolipoprotein E (ApoE) alleles in the pathogenesis of Alzheimer's disease and other CNS diseases, we generated recombinant AAV-apoE alleles driven by the GFAP promoter and expressed them in the mouse brain of Alzheimer's disease mouse. High level ApoE expressions in mouse brain lasted for 12 months, and ApoE was specifically expressed in astrocytes. We demonstrate that AAV-GFAP-ApoE is valuable in studying the pathogenesis and in gene therapy for Alzheimer's disease and other CNS diseases.

Alleles↗
PubMed2004

A new locus for autosomal dominant Charcot-Marie-Tooth disease type 2 (CMT2L) maps to chromosome 12q24.

Charcot-Marie-Tooth disease (CMT) is one of the most common inherited neurological disorders with a prevalence estimated at 1/2500. The axonal form of this disorder is referred to as Charcot-Marie-Tooth type 2 disease (CMT2). Recently, a large Chinese family with CMT2 was found in the Hunan and Hubei provinces of China. The known loci for CMT1A, CMT2D, CMT1B (the same locus is also responsible for CMT2I and CMT2J), CMT2A, CMT2E, and CMT2F were excluded in this family by linkage analysis. A genome-wide screening was then carried out, and the results revealed linkage of CMT2 to a locus at chromosome 12q24. Haplotype construction and analyses localized this novel locus to a 6.8-cM interval between microsatellite markers D12S366 and D12S1611. The maximal two-point LOD score of 6.35 and multipoint LOD score of 8.08 for marker D12S76 at a recombination fraction (theta) of 0 strongly supported linkage to this locus. Thus, CMT2 neuropathy in this family represents a novel genetic entity that we have designated as CMT2L.

Adolescent↗
PubMed2004

A novel E1A-E1B mutant adenovirus induces glioma regression in vivo.

Malignant gliomas are the most frequently occurring primary brain tumors and are resistant to conventional therapy. Conditionally replicating adenoviruses are a novel strategy in glioma treatment. Clinical trials using E1B mutant adenoviruses have been reported recently and E1A mutant replication-competent adenoviruses are in advanced preclinical testing. Here we constructed a novel replication-selective adenovirus (CB1) incorporating a double deletion of a 24 bp Rb-binding region in the E1a gene, and a 903 bp deleted region in the E1b gene that abrogates the expression of a p53-binding E1B-55 kDa protein. CB1 exerted a potent anticancer effect in vitro in U-251 MG, U-373 MG, and D-54 MG human glioma cell lines, as assessed by qualitative and quantitative viability assays. Replication analyses demonstrated that CB1 replicates in vitro in human glioma cells. Importantly, CB1 acquired a highly attenuated replicative phenotype in both serum-starved and proliferating normal human astrocytes. In vivo experiments using intracranially implanted D-54 MG glioma xenografts in nude mice showed that a single dose of CB1 (1.5 x 10(8) PFU/tumor) significantly improved survival. Immunohistochemical analyses of expressed adenoviral proteins confirmed adenoviral replication within the tumors. The CB1 oncolytic adenovirus induces a potent antiglioma effect and could ultimately demonstrate clinical relevance and therapeutic utility.

Adenovirus E1A Proteins↗
PubMed2004

Three novel mutations of the spastin gene in Chinese patients with hereditary spastic paraplegia.

BACKGROUND: Hereditary spastic paraplegia is a group of genetically heterogeneous neurodegenerative disorders characterized by progressive spasticity of the lower limbs. The most common form of hereditary spastic paraplegia is caused by mutations in the spastin gene (SPG4), which encodes spastin, an adenosine triphosphatase associated with various cellular activities protein. OBJECTIVE: To investigate the Chinese patients with hereditary spastic paraplegia for mutations in SPG4. METHODS: DNA samples from 31 unrelated patients were analyzed for mutations in SPG4 by single-strand conformation polymorphism analysis and direct sequencing. All DNA samples were screened for mutations by the polymerase chain reaction, followed by electrophoresis and silver staining. Each new variant identified was analyzed in 50 control subjects to determine whether it is a polymorphism or a mutation. RESULTS: Three novel mutations were detected in 4 affected individuals, including 2 missense mutations (T1258A and A1293G) and 1 deletion mutation (1668-1670delCTA). CONCLUSIONS: To our knowledge, this is the first report of SPG4 mutations in the People's Republic of China. The percentage of involved Chinese families with autosomal dominant hereditary spastic paraplegia with an SPG4 mutation is 18% (4/22), lower than the estimated 40% linked to this locus.

Adenosine Triphosphatases↗
PubMed2004

Time dependent effects of 6-OHDA lesions on iron level and neuronal loss in rat nigrostriatal system.

The early changes in iron level and neuronal loss in rat nigrostriatal system were investigated using 6-hydroxydopamine (6-OHDA) unilaterally lesioned rats. The results showed that: 1, 3, 5, 7, and 14 days of postlesion, there was a progressive reduction in the density of the tyrosine hydroxylase immunoreactive (TH-ir) cells in the lesioned substantia nigra (SN). Iron level increased in the lesioned SN from 1-14 days following 6-OHDA lesions, but there were no differences in iron level among them. Only on 14 days of postlesion, did the DA release decrease in striatum (Str) of the lesioned side, while there were no changes in other groups. These results implied that the increased iron level in SN occured when there was a moderate reduction of DA neurons. However, the DA release in Str was unchanged until TH-ir cells were highly reduced due to the immense compensatory mechanism of the DA system.

Animals↗
PubMed2004

Time course of inflammatory response after renal artery stenting in patients with atherosclerotic renal stenosis.

BACKGROUND: Inflammatory response has been demonstrated in patients with coronary artery disease after percutaneous coronary intervention (PCI). Such response following renal artery stenting has not yet been established, however, in patients with atherosclerotic renal artery stenosis. METHODS: A total of 44 patients were enrolled in this study. Of them, 22 patients with atherosclerotic renal artery stenosis received renal angioplasty with stent (group A, mean age 51+/-8 years), and 22 patients with age- and gender-matched underwent renal angiography for diagnostic purpose as a control group (group B, age 50+/-8 years). The peripheral blood samples were taken immediately before the procedure, 1, 6 and 24 h after the procedure in both groups. The concentrations of C-reactive protein (CRP) and interleukin-6 (IL-6) were measured using ELISA. RESULTS: The result showed that there was no difference in clinical characteristics and baseline levels of CRP and IL-6 between the groups. The IL-6 increased in the first hour (before: 5.8+/-3 pg/ml; 1 h: 8.6+/-5 pg/ml, p<0.01), lasted at 6 h (12.2+/-8 pg/ml), returned to baseline at 24 h (5.4+/-3 pg/ml) in group A. The CRP did not changed at the first hour after stenting, but mean CRP increased from 0.30+/-0.09 to 0.37+/-0.15 mg/dl at 6 h (p<0.05), and peaked at 24 h (0.43+/-0.18 mg/dl, p<0.001 compared with baseline and control) after stenting in group A, while no such changes were observed in group B (p>0.05 at different time points compared with baseline and group B, respectively). CONCLUSIONS: The data indicated that renal artery stenting could trigger inflammatory response by evidence of increased plasma levels of CRP and IL-6. IL-6, however, was an early initiator of inflammatory cytokine, and CRP was a later marker of systemic inflammatory response to renal artery stenting.

Adult↗
PubMed2004

Robust infectivity and replication of Delta-24 adenovirus induce cell death in human medulloblastoma.

The diverse advanced treatment modalities currently available to children with medulloblastoma, including surgery and radiotherapy, are associated with deleterious side effects and often with an unfavorable prognosis. A mutant adenovirus, Delta-24, which has a 24-base pair deletion in the Rb-binding region of the E1A gene, demonstrates selective replication and oncolysis in various malignant phenotypes. Here we report the ability of Delta-24 to kill medulloblastoma cells. Flow cytometric analyses of cell receptors demonstrated expression of the coxsackie adenovirus receptor and RGD-related integrins in the assessed medulloblastoma cell lines. Infectivity assays using a replication-deficient adenovirus to transduce the green fluorescence protein gene showed that the Delta-24 adenovirus infects 99% of Daoy and 46% of D283 Med medulloblastoma cells at a multiplicity of infection (MOI) of 50. Within 4 days after infecting medulloblastoma cells with Delta-24, a noticeable cytopathic effect was produced. Delta-24 induced a total cytopathic effect in Daoy and D283 Med medulloblastoma cells after 6 and 8 days of infection, respectively. In the infected population of cells, cell death correlated with the accumulation of cells in the S phase. At 5 days post-infection with 2.5 MOIs of Delta-24 adenovirus, the percentage of Daoy medulloblastoma cells in the S phase increased to 71.9+/-5.5%, compared with control values of 20.5+/-1.4%. The release of viral progeny was quantified as being increased by two orders of magnitude, indicating efficient replication of Delta-24 in medulloblastoma cells. This is the first report of the ability of oncolytic adenoviruses to infect and kill medulloblastoma cells, the findings of which suggest the potential efficacy of Delta-24 as a therapy for human medulloblastoma tumors.

Adenoviridae↗
PubMed2004

Defects in secretion, aggregation, and thrombus formation in platelets from mice lacking Akt2.

Prior studies have shown that PI3Ks play a necessary but incompletely defined role in platelet activation. One potential effector for PI3K is the serine/threonine kinase, Akt, whose contribution to platelet activation was explored here. Two isoforms of Akt were detected in mouse platelets, with expression of Akt2 being greater than Akt1. Deletion of the gene encoding Akt2 impaired platelet aggregation, fibrinogen binding, and granule secretion, especially in response to low concentrations of agonists that activate the G(q)-coupled receptors for thrombin and thromboxane A(2). Loss of Akt2 also impaired arterial thrombus formation and stability in vivo, despite having little effect on platelet responses to collagen and ADP. In contrast, reducing Akt1 expression had no effect except when Akt2 was also deleted. Activation of Akt by thrombin was abolished by deletion of Galpha(q) but was relatively unaffected by deletion of Galpha(i2), which abolished Akt activation by ADP. From these results we conclude that Akt2 is a necessary component of PI3K-dependent signaling downstream of G(q)-coupled receptors, promoting thrombus growth and stability in part by supporting secretion. The contribution of Akt1 is less evident except in the setting in which Akt2 is absent.

Animals↗
PubMed2004

An integrated view of suppressor T cell subsets in immunoregulation.

The immune system evolved to protect organisms from a virtually infinite variety of disease-causing agents but to avoid harmful responses to self. Because immune protective mechanisms include the elaboration of potent inflammatory molecules, antibodies, and killer cell activation--which together can not only destroy invading microorganisms, pathogenic autoreactive cells, and tumors, but also mortally injure normal cells--the immune system is inherently a "double-edged sword" and must be tightly regulated. Immune response regulation includes homeostatic mechanisms intrinsic to the activation and differentiation of antigen-triggered immunocompetent cells and extrinsic mechanisms mediated by suppressor cells. This review series will focus on recent advances indicating that distinct subsets of regulatory CD4+ and CD8+ T cells as well as NK T cells control the outgrowth of potentially pathogenic antigen-reactive T cells and will highlight the evidence that these suppressor T cells may play potentially important clinical roles in preventing and treating immune-mediated disease. Here we provide a historical overview of suppressor cells and the experimental basis for the existence of functionally and phenotypically distinct suppressor subsets. Finally, we will speculate on how the distinct suppressor cell subsets may function in concert to regulate immune responses.

Animals↗
PubMed2004

Differences in the changing trends of monophasic action potential duration and effective refractory period of the ventricular myocardium after myocardial infarction in vivo.

BACKGROUND: The relationship between monophasic action potential duration (MAPD) and effective refractory period (ERP) is poorly understood after myocardial infarction (MI) in vivo. METHODS AND RESULTS: Forty rabbits were randomized into either a sham operation (SO) group (n=10) or MI group (n=30), both of which underwent thoracotomy, but the left anterior descending coronary artery was occluded in the MI group only. The MAPD and ERP of the endocardial, midmyocardial and epicardial cells of the infarction zone were observed at baseline, 2 days after thoracotomy and then 5 min, 15 min, 30 min, 2 days, 14 days and 60 days after coronary occlusion (CO). At baseline, ERP correlated strongly with MAPD90. During the 5-30 min after CO, both MAPD90 and ERP of the 3 layers of the myocardium shortened markedly (eg, MAPD90 Mid) was approximately 50% of the baseline value at 5 min after CO). MAPD90 and ERP recovered gradually over the 2-60 days after MI. ERPMid exceeded MAPD90 Mid and the post repolarization refractoriness phenomenon appeared during the 5-30 min after CO. CONCLUSIONS: The different changing trends of the MAPD and ERP of the mid-myocardial cells may underlie the arrhythmias that occur after MI.

Action Potentials↗
PubMed2004

[The establishment and application of network human sperm bank management information system].

OBJECTIVE: To build network human sperm bank management information system. METHODS: The system was developed with SQL Server 2000 and Power Builders 8.0. RESULTS: The system consisted of 4 modules: file management, physical check-up and laboratory examination management, sperm examination and freezing management, supply and follows-up management. The system worked by long-distance transmission and real time supervision. CONCLUSION: The system possesses the advantages of huge information content, great safety and high confidentiality, as well as the functions of long-distance transmission and real time supervision.

Humans↗
PubMed2004

[Application of collagen-binding assay for von Willebrand disease].

OBJECTIVE: To explore the application of collagen-binding assay for von Willebrand disease (vWD). METHODS: We investigated the sensitivity and reproducibility of collagen-binding assays (CBA) of vWF using the enzyme-linked immunosorbent assay (ELISA) technique and compared CBA with 3 other assays for their ability to detect vWD. RESULTS: It was found that the vWF: CBA level of plasma from patients with different types of vWD is lower than that from healthy donors, hemophilia and other bleeding disorders (P < 0.001). In general, the four assays have the capability to identify vWD from normal and other bleeding disorders, and can be used for diagnosing vWD. The concordance rates of the four assays on vWD are vWF: Ag 85.7%, vWF: Rcof 76.2%, RIPA 80.9%, vWF: CBA 95.2% respectively. CONCLUSION: vWF: CBA measured by ELISA is highly sensitive, specific and reproducible, and easy to operate. The measurement of the functional activity of vWF by vWF: Rcof or RIPA can be replaced by the more reliable vWF: CBA.

Biological Assay↗
PubMed2004

Brain IL-1 beta was involved in reserpine-induced behavioral depression in rats.

AIM: To investigate the mechanism of brain interleukin-1 beta (IL-1 beta) in reserpine-induced behavioral depression in rats. METHODS: Porsult swim test was used in the measurement of depressive behavior and ELISA was used in measurement of brain IL-1 beta. RESULTS: Intraperitoneal injection of reserpine (0, 4, 6, and 8 mg/kg, ip) increased floating time in the Porsult swim test in a dose-and time-dependent manner in rats. Intracerebroventricular injection (icv) of IL-1 beta receptor antagonist (IL-1ra, 6 mg/kg) blocked the increment of floating time in Porsult swim test at 48 and 72 h after reserpine injection, but not at 1 and 24 h after injection. Brain IL-1 beta increased after reserpine treatment in posterior cortex, hippocampus, and hypothalamus. The increase of IL-1 beta concentration starts at 24 hours after injection of reserpine and reached the peak at 48 h. CONCLUSION: Reserpine induced behavioral depression partially via brain interleukin-1 beta generation.

Animals↗
PubMed2004

[Relationship between the 4G/5G polymorphism of the plasminogen activator inhibitor-1 gene and the pathogenesis of pregnancy-induced hypertension syndrome].

OBJECTIVE: To investigate the relationship between a single nucleotide insertion/deletion(4G/5G) polymorphism located in the promoter region of the plasminogen activator inhibitor-1(PAI-1) gene and the pathogenesis of pregnancy-induced hypertension syndrome(PIHs). METHODS: The 4G/5G polymorphism of PAI-1 gene in 171 PIHs patients (PIHs group) and that in 193 normal pregnant women (control group) were detected by a combination of polymerase chain reaction-restriction fragment length polymorphism. RESULTS: (1)The genotype frequencies of PAI-1 gene in PIHs group were 47.4% for 4G/4G, 41.5% for 4G/5G, and 11.1% for 5G/5G. The 4G/4G genotype and 4G allele frequencies of PAI-1 gene(47.4% and 0.681) for PIHs patients were higher than those (21.2% and 0.495) for normal controls respectively (P<0.001). (2)Both the 4G/4G genotype and the 4G allele of PAI-1 gene occurred more frequently in the severe PIHs group(61.3% and 0.758) than those (35.8% and 0.623) in the mild PIHs group respectively (P<0.001). However, there were no significant differences between those in mild group (35.8% and 0.623) and moderate group(42.8% and 0.625) respectively. (3) The 4G/4G genotype was significantly associated with PIHs (OR=3.34, 95%CI: 2.14-5.22). CONCLUSION: These findings suggested that PAI-1 gene polymorphism may be a susceptible factor to the pathogenesis of PIHs and the 4G/4G genotype may be one of the major risk factors for PIHs in pregnant women.

Adult↗
PubMed2004

[Effects of zinc on content of uncoupling protein in cold stress rats].

OBJECTIVE: To study effects and regulatory mechanism of zinc on cold stress in rats. METHODS: Sixty male SD rats were randomized into 4 groups. Rats of group I and III drank tap water, group II and IV drank high-zinc water[1 mg/(kg.d)], respectively, and 5 days later, rats from group III and IV underwent exposure to cold-15 degrees C for 2 hours. The rectal temperature before and after cold exposure were assayed. Zinc concentration in plasma and tissue were assayed. Radioactivity was measured by liquid glimmer instrument using 3H-GTP binded UCPin mitochondria. The dissociation constant(Kd) and maximal binding(Bmax) was determined from Scathardplot. RESULTS: The decreased range of rectal temperature during cold exposure of group zinc and control were -2.95 +/- 0.61 and -1.16 +/- 0.39(P < 0.05), respectively. There was a significant increase in the content of zinc in the tissue after cold exposure. With zinc and cold treatment, Bmax increased, Kd remained unchanged. CONCLUSION: Zinc might play an important role in cold stress and cold endurance through increase concentration of UCP in brown adipose tissue mitochondria.

Adipose Tissue, Brown↗