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J Mi

Publications and source records attributed to J Mi.

15 recordsLinked to original sources
PubMed2001

Effect of large-scale intermittency and mean shear on scaling-range exponents in a turbulent jet.

The present study investigates the combined impact of the intermittency associated with the turbulent-nonturbulent interface and the mean shear rate in an axisymmetric jet on the structure of turbulence in the scaling range, where the spectrum exhibits a power-law behavior. Second-order structure functions, autocorrelations of the dissipation rate, and spectra of both the longitudinal velocity fluctuation and the passive temperature fluctuation are measured at a distance of 40 diameter downstream from the nozzle exit. All the scaling range exponents are influenced by the large-scale intermittency and the mean shear. The scalar fluctuation is much more sensitive to the variation in large-scale intermittency than the velocity fluctuation.

Journal Article↗
PubMed2001

Induced apoptosis supports spread of adenovirus vectors in tumors.

Selectively replicating viruses hold promise as anticancer agents. To eliminate the tumor, these viruses must efficiently spread throughout the tumor and induce oncolysis. We hypothesized that viral release and spread could be supported by apoptosis induced after assembly of de novo-produced virions in tumor cells. As a model to test this, we employed an adenovirus vector that replicated in human tumor cell lines. Expression of a dominant-negative I-kappaB from this vector sensitized tumor cells to recombinant human tumor necrosis factor alpha (TNF-alpha)-mediated apoptosis. We found that apoptosis induced during viral DNA replication compromised virus production, whereas apoptosis induced after virion assembly enhanced viral release from infected cells and dissemination. Electron microscopy demonstrated that viral particles were associated with or included in apoptotic bodies whose phagocytosis by neighboring cells provides a potential means for viral spread. Apoptosis induced after viral replication also supported spread in vivo, in subcutaneous tumors or liver metastases, resulting in a delay of tumor growth. Our findings could be applicable to other selectively replicating viruses or antitumor strategies that involve application of proapoptotic or cytolytic agents.

Adenoviridae↗
PubMed2001

Identification and characterization of DPZF, a novel human BTB/POZ zinc finger protein sharing homology to BCL-6.

The C2H2 zinc finger protein family is one of the largest families of transcription factors. We identified a novel BTB/POZ zinc finger gene from human dendritic cells (DC), which encodes a 733-residue protein with a BTB/POZ domain at the N-terminal and 4 C2H2 zinc fingers at C-terminal. It was designated dendritic cell-derived BTB/POZ zinc finger (DPZF). DPZF protein shares closest homology to BCL-6, with the highest homology present in the BTB/POZ and zinc finger domains. Like BCL-6, DPZF gene is localized on chromosome 3. It is widely expressed in hematopoietic tissues, including DC, monocytes, B cells, and T cells. DPZF protein expression is detectable in lymphoid neoplasm with a molecular mass of 100 kD, especially in B lymphoma. These indicate that DPZF may be a transcription factor closely related to BCL-6, and may be involved in hematopoiesis, oncogenesis, and immune responses.

Amino Acid Sequence↗
PubMed2001

Precise measurement of the positive muon anomalous magnetic moment.

A precise measurement of the anomalous g value, a(mu) = (g-2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron. The result a(mu+) = 11 659 202(14) (6) x 10(-10) (1.3 ppm) is in good agreement with previous measurements and has an error one third that of the combined previous data. The current theoretical value from the standard model is a(mu)(SM) = 11 659 159.6(6.7) x 10(-10) (0.57 ppm) and a(mu)(exp) - a(mu)(SM) = 43(16) x 10(-10) in which a(mu)(exp) is the world average experimental value.

Journal Article↗
PubMed2001

The potent antitumor effects of combined p16 gene and GM-CSF gene therapy through efficient induction of antitumor immunity.

PURPOSE: Tumor suppressor gene therapy and cytokine gene therapy have limited antitumor effects when used alone. Thus, in the present study, we investigated the antitumor potentials of the combined transfer of the p16 tumor suppressor gene and the murine granulocyte-macrophage colony-stimulating factor (GM-CSF) gene. METHODS: The adenovirus-harboring p16 gene (Adp16) and adenovirus-harboring GM-CSF (AdGMCSF) gene were utilized for the treatment of established tumors in vivo. The mice were inoculated s.c. with Renca renal carcinoma cells and 3 days later received an intratumoral injection of Adp16 in combination with AdGMCSF. RESULTS: The results demonstrated that tumor-bearing mice treated with Adp16 and Ad-GMCSF showed more potent inhibition of tumor growth and a prolonged survival period than mice treated with Adp16. AdGMCSF, adenovirus-expressing beta-galactosidase or PBS (P<0.01). Treatments of the mice with Adp16 alone or AdGMCSF alone also showed obvious antitumor effects as compared with those mice treated with PBS (P<0.05). After combined p16 and AdGMCSF gene therapy, the expression of H2Kd and Fas molecules on freshly isolated tumor cells increased markedly, and more CD(4)+ T cells and CD(8)+ T cells infiltrated in the tumor sites. The cytotoxicity of natural killer cells and specific cytotoxic T lymphocytes increased more significantly after the combined therapy. CONCLUSIONS: Our results demonstrated that combination p16 gene and GM-CSF gene therapy could inhibit the growth of established tumors in mice more significantly through efficient induction of antitumor immunity.

Adenoviridae↗
PubMed2001

IFN-gamma gene therapy by intrasplenic hepatocyte transplantation: a novel strategy for reversing hepatic fibrosis in Schistosoma japonicum-infected mice.

Liver-targeted gene therapy using hepatocyte as recipient cells has recently been documented to be effective in treatment of numerous hepatic diseases, such as metabolic diseases and liver carcinoma. IFN-gamma elicits antipreliferative and antifibrogenic activity in a variety of mesenchymal cells, including hepatic satellite cells. To investigate the antifibrogenic response of liver gene therapy mediated by intrasplenic transplantation of gene-modified hepatocytes, normal mouse liver cell line BNL CL.2 cells were transfected with murine IFN-gamma gene (BNL.IFN-gamma) in vitro, and transplanted intrasplenically into Schistosoma japonicum-infected mice. The amounts and distribution of IFN-gamma (which inhibits collagen synthesis), TGF-beta (which stimulates collagen synthesis) and extracellular matrix, including type I and III collagen, were detected. In mice infected with S. japonicum and then treated with BNL.IFN-gamma, an increase of IFN-gamma and decrease of TGF-beta1 were detected at 20 weeks postinfection compared to untreated S. japonicum-infected mice. Immunohistochemical analysis showed that S. japonicum infection induced a marked increase of type I and III collagen synthesis. Whereas, 4 weeks after treatment with BNL.IFN-gamma, net synthesis rates of type I and III collagen were markedly decreased in the liver of infected mice. In addition, a decreased expression of TGF-beta1 and its receptor TGF-betaRII in the liver of BNL.IFN-gamma-treated mice was also observed. Moreover, the decrease in TGF-beta1 and TGF-betaRII protein approximately paralleled the decrease in their mRNA expression, which was detected by RNA dot blotting. The data indicate that intrasplenic transplantation of IFN-gamma gene-modified hepatocyte can be a candidate approach to treat hepatic fibrosis.

Animals↗
PubMed2001

[The tissue engineering research on synovialization of non-synovial membrane tendon].

The synovial membrane tissue within the flexor digital tendon sheath of the rabbit's toes was cultured in vitro. The synovial cells suspension of the subculture was cultured with the segments of the non-synovial membrane tendon of the rabbit's toes. Under the light microscopy, scanning electronic microscopy and immunohistochemical examination, the result showed that the synovial cells crawled and covered the surface of the segments of the non-synovial membrane tendons. It is suggested that the non-synovial membrane tendon could transform into a synovial membrane tendon.

Animals↗
PubMed2000

Anti-DNA antibodies exhibit different binding motif preferences for single stranded or double stranded DNA.

A common feature for most anti-DNA antibodies (Abs) is their induction in an antigen (Ag)-driven specific clonal expansion pattern though crossreactivity. However, the fine sequences in DNA Ags that interact directly with immune system and the ability of DNA to induce immune responses is poorly understood. In order to define the characteristics of possible antigenic determinants in DNA Ags, we immunized mice with the pBR322 plasmid and used antisera as source of anti-DNA Abs. A systemic evolution of ligands by exponential enrichment (SELEX) procedure was performed on an oligodeoxynucleotide library either in single stranded (ss-) or double stranded (ds-) form. The SELEXed fragments were cloned and sequenced. The resulting sequences were analyzed using the Multiple Alignment Construction and Analysis Workbench program. We show that the fragments of ss- or ds- form bound by a same stock of antibodies were different in their conserved sequences. ss-DNA fragments recognized by anti-DNA Abs were rich in cacc, caccc, accc or cccc blocks, while the same stock of Abs exhibited significant preference for the (5'gcg3'/3'cgc5') motif located in ds-DNA. At the same time sera from unimmunized control mice showed no sequence preference in either ss-DNA or ds-DNA. Future improvement of this work and the potential use of SELEX for studies of DNA Ags are also discussed.

Animals↗
PubMed2000

Effects of infant birthweight and maternal body mass index in pregnancy on components of the insulin resistance syndrome in China.

BACKGROUND: Reduced birthweight is associated with increased risk for the insulin resistance syndrome. Part of this risk is hypothesized to originate from undernutrition in utero. The prevalence of the insulin resistance syndrome increases in countries that undergo the transition from chronic malnutrition to adequate nutrition, when postnatal nutrition improves more rapidly than prenatal nutrition. OBJECTIVE: To determine whether the components of the insulin resistance syndrome are associated with reduced fetal growth and maternal undernutrition. DESIGN: A nonconcurrent, prospective study of men and women whose mothers' heights and weights were recorded during pregnancy. SETTING: Beijing, China. PARTICIPANTS: 627 men and women (mean age, 45 years) whose mothers' obstetric records were preserved. MEASUREMENTS: Adult offspring's blood pressure, plasma glucose levels, insulin levels, and lipid concentrations during an oral glucose tolerance test. The main explanatory measurements were mothers' body mass index during pregnancy and offspring's birthweight and adult size. RESULTS: After adjustment for sex and current body mass index, low birthweight was associated with elevated plasma glucose levels, insulin levels, triglyceride concentrations, and blood pressure. For every 1-kg increase in birthweight, systolic blood pressure decreased by 2.9 mm Hg (95% CI, 0.3 to 5.4 mm Hg) and the 2-hour plasma glucose level decreased by 5.1% (CI, 0.7% to 9.3%). Low maternal body mass index in early and late pregnancy was associated with elevated levels of plasma glucose, insulin, and triglycerides in adult offspring but was not associated with elevated blood pressure. CONCLUSIONS: Risk for the insulin resistance syndrome may be partially established through low maternal body mass before pregnancy and consequent fetal undernutrition. This risk is independent of that associated with adult obesity. In developing countries such as China, improved nutrition in girls and young women may offer long-term benefits to offspring.

Adult↗
PubMed1999

Recombinant adeno-associated virus (AAV) drives constitutive production of glutamate decarboxylase in neural cell lines.

Many neurological disorders result directly or indirectly from the loss of inhibitory function. Engineering the production of GABA, an inhibitory neurotransmitter, may therefore be able at least partly to restore the lost inhibition seen in epilepsy, Parkinson's disease, or Huntington's disease. In this article, we describe a set of recombinant adeno-associated viruses (AAVs) that can deliver cDNAs encoding the GABA-producing enzyme, glutamate decarboxylase (GAD), directly into neural cells. We have characterized these recombinant AAVs in several cell lines derived from the CNS. These recombinant AAVs effectively transduced all neural cell lines, although with different efficiencies. Transduction occurred in both proliferating and nonproliferating cells, but actively proliferating cell lines had approximately six times greater transduction efficiency than nonproliferating cells. Furthermore, these AAVs maintained long-term expression of GAD in an astrocytic cell line for at least seven passages. These recombinant AAVs are promising vehicles for investigating the potential therapeutic effects of GABA in animal models of epilepsy and neurodegenerative diseases.

Animals↗
PubMed1994

Extensive anterior decompression for mixed cervical spondylosis. Resection of uncovertebral joints, neural and transverse foraminotomy, subtotal corpectomy, and fusion with strut graft.

STUDY DESIGN: This study examined a new operative procedure for treating mixed cervical spondylosis. OBJECTIVES: To relate postoperative results with extensive decompression using a surgical microscope. SUMMARY OF BACKGROUND DATA: Based on the dissection cadavers and clinical practice, extensive anterior decompression has been designed for mixed cervical spondylosis. It has not been reported that the cervical cord, nerve roots, and vertebral arteries have been decompressed thoroughly at the same time. METHODS: Fifteen patients with mixed cervical spondylosis were treated with extensive anterior decompression using an operative microscope. The pathologic segments in all patients were identified preoperatively with cervical radiography, myelography, computed tomography, computed tomographic myelography, and magnetic resonance imaging. The Japanese Orthopaedic Association classification was used to assess the follow-up results. The operative results demonstrated the efficacy of the surgical approach. RESULTS: All patients improved neurologically, with the average Japanese Orthopaedic Association score improving from 6.3 points preoperatively to 12.4 points at follow-up examination. The plain radiography, computed tomography, and magnetic resonance imaging follow-up examination showed that the anterior part of the cervical canal and the transversaria or neural foramina were enlarged, and that there was satisfactory bony fusion without signs of nonunion and other complications. CONCLUSIONS: Extensive anterior decompression (resection of uncovertebral joints, neural and transverse foraminotomy, subtotal corpectomy, and fusion with strut graft), a new surgical procedure for treating mixed cervical spondylosis, led to excellent follow-up results.

Adult↗
PubMed1992

[Construction and identification of vectors containing maize plasmid-like DNA S1 and reporter genes].

The reporter Gene GUS with CaMV 35S promoter was inserted into plasmid pBS[1] in reversal direction of integration, and two kinds of recombinant plasmids were obtained. These results were verified by restriction endonuclease analysis and southern hybridization. A piece of 10.8kb fragment containing NPT II reporter gene from digested pBI121.1 by BamHI and EcoRI was ligated together with 3.9 kb fragment of plasmid-like DNA S1. Then generate a recombinant plasmid pBIS5 was generated. These three vectors can be used to transform maize protoplasts. High frequency of transformation may be expected due to homology between plasmid-like DNA S1 and maize nuclear DNA.

DNA↗