Biomedical subjects

Hong Zhang

Publications and source records attributed to Hong Zhang.

At least 505 records · Page 28Linked to original sources

PubMed2002

Detection of soluble HLA class I antigens by ELISA and determination of its reference value in population of Guangdong province.

OBJECTIVE: To explore a method for quantitative detection of soluble human leukocyte antigen class I(HLA-I) antigens, with the assistance of which we attempt to define the reference value of the antigen in the population of Guangdong Province. METHODS: Sandwich enzyme-linked immunosorbent assay (ELISA) was employed with W6/32 monoclonal antibody serving as the solid phase antibody and beta2 microglobulin antibody as the first antibody. HRP-labeled second antibody and the substrate were added for enzyme-catalyzed coloring. On the basis of the standard curve obtained by sHLA-I standard reagent in serial dilution, the concentration of sHLA-I antigens in the samples of 60 normal subjects from the population of Guangdong province was detected. RESULTS: The sensitivity of this assay was 2.84 ng/ml with variation coefficients of 5.80% within the same batch and 9.00% between batches. The recovery rate ranged from 98.57% to 100.15%. The level of sHLA-I antigens in normal individuals was 699.54+/-360.10 ng/ml. CONCLUSION: Sandwich ELISA is sensitive, specific and stable in the detection of sHLA-I.

Adult↗

PubMed2002

[Clinical analysis of 271 cases of orbital inflammatory pseudotumors].

OBJECTIVE: To analyze and summarize the clinical signs, the diagnostic and differential diagnostic value of imaging examination in orbital inflammatory pseudo-tumors and the comparison of the therapeutic effect of various treatments. METHOD: Retrospectively, 271 cases (303 eyes) of orbital inflammatory pseudotumors were analyzed. RESULTS: Ultrasonography and CT had their diverse manifestations according to the different characterizations of the histopathology of tumors. B-ultrasonography showed a tumor with low reflection and strong sound transmission in diffuse lymphocytic infiltrative pseudotumor. A tumor with fibro-proliferative lesion had low reflection, weak sound transmission and irregular border. CT showed lesions touching closely with the globe. Steroid and radiotherapy were effective for diffuse lymphocytic infiltrative pseudotumors. The various therapies were not effective for fibro-proliferative lesions. CONCLUSION: Imaging examinations are valuable for the diagnosis, differential diagnosis, the evaluation of histopathology types and the choice of treatment for orbital inflammatory pseudotumors.

Adolescent↗

PubMed2002

[Familial membranous nephropathy: an analysis of 3 kindreds and literature review].

OBJECTIVE: To report three kindreds of familial membranous nephropathy and describe its clinical and pathological characteristics. METHODS: 6 patients with renal biopsy proved familial membranous nephropathy from 3 kindreds were described. Their clinical and pathological data were compared with 33 patients who were also suffering from familial membranous nephropathy from 16 kindreds documented in PubMed and 30 sporadic patients who were collected in our hospital with membranous nephropathy. RESULTS: Compared with the patients documented in the literatures, the patients were older and the ratios of male and female patients in this series were equal. In both series, the pathological lesions were severe. Compared with sporadic patients with membranous nephropathy, the patients in familial form had severer pathological lesions. There were no differences among all patients in clinical manifestations, such as proteinuria, hypertension and renal function. The major clinical symptom in familial membranous nephropathy patients was nephritic syndrome. CONCLUSIONS: The present study first reported the kindreds of familial membranous nephropathy in China. The clinical manifestations of familial membranous nephropathy in our patients, as well as in other familial cases reported to date, are similar with those in the non-familial membranous nephropathy patients, but the pathological changes in the familial cases were severer than those in the non-familial. To distinguish the familial form from idiopathic membranous nephropathy, it is essential to understand the genetic factors underlying this disease.

Adolescent↗

PubMed2002

[Transvaginal sonography and transabdominal sonography in the diagnosis of ectopic pregnancy in the fallopian tubal: a comparative study in 38 cases].

OBJECTIVE: To compare the accuracy of transvaginal sonography (TVS) and transabdominal sonography (TAS) in the diagnosis of ectopic pregnancy occurring in the fallopian tubal. METHODS: Thirty-eight patients with ectopic pregnancy in the fallopian tube were examined by TAS with moderately filled bladder, followed by reexamination with TVS with the bladder emptied. The manifestations in the 2 imaging examinations were compared. RESULTS: TVS showed masses in 38, gestations in 23, heart beat in 10, pelvis fluid in 16 and circular blood signal in 25 cases respectively, while TAS identified masses in 30, gestations in 13, heart beat in 5, pelvis fluid in 14 and circular blood flow signal in 13 cases. CONCLUSION: TVS may offer an earlier, clearer and more exact diagnosis of ectopic pregnancy in the fallopian tube than TAS is capable of.

Abdomen↗

PubMed2002

Intervention by azithromycin on bleomycin-induced lung injury in rats and its mechanisms.

OBJECTIVE: To study the role of Th1/Th2 balance in the pathogenesis of pulmonary fibrosis and to investigate the therapeutic mechanisms of azithromycin. METHODS: Male wistar rats were randomly divided into three experimental groups: the bleomycin A(5) (BLM) group (BLM group), the azithromycin (AZI) group (AZI group) and the control group. Quantitative analysis of the histopathologic changes was performed by computer gray scan. The expression of IL-10 mRNA and IFN-gamma mRNA was examined by RNase protection assay (RPA). RESULTS: (1) In the BLM group, up-regulation of IL-10 mRNA was stronger than that of IFN-gamma mRNA, resulting in the inversion of the IL-10/IFN-gamma mRNA ratio, a shift from the Th1-like response of IFN-gamma predominance in the control group to the Th2-like response of IL-10 predominance in the BLM group. (2) The oral administration of AZI inhibited the expression of IL-10 and IFN-gamma mRNA; reversed the Th2-like response in the BLM group to the Th1-like response on day 7; and decreased the exudation of inflammatory cells as well as the degree of fibrosis. CONCLUSIONS: (1) At the early stage of fibrosing alveolitis, Th2 domination and the lack of IFN-gamma in the presence of alveolar epithelial and basement membrane injury may promote the development of fibrosis. (2) Azithromycin can inhibit the expression of IL-10 and IFN-gamma, and reverse the Th2-like response in the BLM group to a Th1-like response, and as a result, decrease the inflammatory injury as well as the degree of BLM-induced lung injury in rats.

Animals↗

PubMed2002

[The change in apoptosis and proliferation of pulmonary tissue cells in rats with smoke inhalation injury].

OBJECTIVE: To observe the rule of the change of apoptosis and proliferation of pulmonary tissue cells in rats with inhalation injury, so as to explore the significance of apoptosis in the repairing process of pulmonary tissue injury. METHODS: Smoke inhalation injury model was established in rats. The rats were randomly divided into normal control (NC) and smoke inhalation injury (SI) groups. TUNEL and immunohistochemistry methods were employed to determine the changes in cellular apoptotic and proliferating cell nuclear antigen (PCNA) indices of the pulmonary tissue at different postburn time points. RESULTS: (1) The apoptotic index increased at 2 postburn hours (PBHs) and remained at high levels thereafter. (2) The PCNA index increased at 12 PBHs, reaching top level at 3 postburn days (PBDs), remaining kept at relativly high level later. CONCLUSION: Apoptosis not only played roles in the early pulmonary injury after smoke inhalation injury, but also participated in the repair and modification of the proliferated tissue during later reconstruction.

Animals↗

PubMed2002

[Clinical analysis of 333 cases of inhalation injury in burned children].

OBJECTIVE: To analyze the clinical features of inhalation injury in children, with the aim of improving its management. METHODS: The incidence of inhalation injury in 333 cases of burned children was analyzed in terms of burn area, shock, infection and prognosis. RESULTS: The incidences of shock and bacteremia were 41.14% and 18.92%, and those of moderate and severe inhalation injury were 58.76% and 31.96% respectively in burned children with inhalation injury. Bacteremia developed in 24.82% of the patients with shock. Among 67 patients who ultimately died, 58.21% of them were complicated with bacteremia ending in 34.33% of mortality. Early tracheostomy was beneficial in that less fluids were required for resuscitation. CONCLUSION: Burn infection was an important factor affecting the prognosis of inhalation injury. And inhalation injury and shock were major inducers of burn infection. Early application of wide spectrum antibiotics and shock management were helpful in lowering of burn infection rate. Early tracheostomy might be beneficial to burn shock management.

Anti-Bacterial Agents↗

PubMed2002

[Demethylation in the promoter area by the antisense of human DNA MTase gene].

OBJECTIVE: To investigate the change in the expression of E-Cadherin of human hepatocarcinoma cell line SMMC-7721 after transfection by antisense human DNA MTase gene. METHODS: DNA MTase gene eukaryotic expression vectors, including sense and antisense fragments, were constructed with recombinant technology and transfected into the hepatocarcinoma cell line SMMC-7721 with liposome DOTAP. The expression of DNA MTase gene mRNA and E-Cadherin gene mRNA was examined with RT-PCR and the expression of E-Cadherin with immunohistochemical and flow cytometry. The status of methylation in E-Cadherin gene promoter area was examined with methylation specific PCR (MSP). RESULTS: The sense and antisense eukaryotic expression vectors were successfully constructed and then the constructed recombinant plasmids were successfully transfected into SMMC-7721 cell with liposome DOTAP. The expression of endogenous DNA MTase mRNA was obviously decreased with E-Cadherin gene mRNA and its activity increased in the SMMC-7721 cell, which was tranfected with antisense DNA MTase gene fragment. Moreover, demethylation in the promoter area of E-Cadherin gene was observed with MSP. CONCLUSION: Demethylation in the promoter area and increasing mRNA level of E-Cadherin gene can be induced by expression inhibition of DNA MTase gene of SMMC-7721 cell line.

Cadherins↗

PubMed2002

[Application of bioptic bone marrow imprint in diagnosis of anemia].

In order to explore the application of bone marrow imprint in diagnosis of anemia, sixty-five diagnosed anemia cases were analyzed with bone marrow imprint, bone marrow biopsy and bone marrow smear. The result showed that the diagnostic rates of bone marrow imprint and biopsy were both significantly higher than bone marrow smear, especially in the cases with myelofibrosis, aplastic anemia and metastatic carcinoma in bone marrow (P < 0.01). There was no significant difference between bone marrow imprint and biopsy, however the bone marrow imprint observed more clearly and more simple and convenient than the bone marrow biopsy. It is concluded that bone marrow imprint is important for diagnosing anemia.

Adolescent↗

PubMed2002

Lifetime cost of HIV care in France during the era of highly active antiretroviral therapy.

OBJECTIVE: To estimate the treatment and health care costs of HIV infection or AIDS in France during the era of highly active antiretroviral therapy (HAART). DESIGN: We used a clinical database of HIV-infected patients to calculate the resource use and cost of care for different stages of HIV infection. Costs were incorporated into a computer-based, probabilistic simulation model of the natural history and treatment of HIV infection to estimate the lifetime cost of treating patients with HIV disease. SETTING: A northern France HIV clinical cohort. PARTICIPANTS: 1232 HIV-infected patients followed from January 1994 through July 1998. RESULTS: In the absence of an AIDS-defining event, the average total cost of care ranged from 670 euros (1 euro=US $1.19) per person-month in the highest CD4 stratum (>500/microl) to 1060 euros per person-month in the lowest CD4 stratum (< or = 50/microl). The mean cost of care was estimated at 3370 euros per person-month during the initial months around the occurrence of an AIDS-defining event; at 1750 euros per person-month during the period spanning from 2 months after the diagnosis of specific AIDS-defining event to 1 month prior to death; and at 13010 euros per person-month in the final month prior to death. If clinical management of HIV infection began at a CD4 cell count of 378/microl, as in this cohort, the discounted lifetime cost of treating an HIV-infected French patient was estimated at 214000 euros. The undiscounted costs were 309000 euros over a projected life expectancy of 16.4 years. CONCLUSION: The cost of HIV disease varies widely depending upon the stage of illness. These estimates of stage-specific and lifetime costs of HIV care will assist health policy planners in assessing the burden of disease in the era of HAART and projecting future resource requirements.

Adult↗

PubMed2002

[Reconstruction of anterior skull base defect by pedicle frontal muscle compound flap].

OBJECTIVE: To evaluate the effect of one stage reconstruction for anterior skull base defect by pedicled frontal muscle compound flap after craniofacial combined approach operation. METHODS: Twelve patients with frontal skull base tumor and fracture (rudimentary cancer 5, malignant melanoma 1, neurogliocytoma 1, ethmoid sinus rhabdomyosarcoma 1, malignant papilloma 1, osteofibroma 2, underwent surgery 1) were included. The compound flap with pedicled frontal muscle galea aponeuroses pericranium was adopted which brought single blood vessel or double, and splinter skull bone. The compound flaps covered 8 cm -12 cm x 10 cm -15 cm. RESULTS: All 12 patients were successfully treated with no complication during follow-up from 1 to 48 months. CONCLUSION: The compound flaps with pedicled frontal muscle galea aponeuroses pericranium, had ample blood supply and thin pliable and strong tissue which was a good reconstruction material for frontal skull base defect.

Adolescent↗

PubMed2002

Clinical significance of TGF- beta1 and beta-glucuronidase synchronous detection in human pancreatic cancer.

OBJECTIVE: To investigate the relation of transfer growth factor (TGF-beta1) and beta-glucuronidase (beta-GCD) on the occurrence and progress of pancreatic cancer. METHODS: The expression of TGF-beta1 and beta-GCD in the pancreatic cancer tissue and normal pancreatic tissue was determined synchronously using ABC method of immunohistochemistry. RESULTS: The percentage of TGF-beta1 positive cells was significantly higher in pancreatic cancer tissue (43.8%+/-5.2%) than in adjacent pancreatic tissue (28.7%+/-3.6%, P<0.01). The worse the cancer cells differentiated and lymph nodes metastasis, the more over-expression of TGF-beta1. The percentage of beta-GCD positive cells was also significantly higher in the pancreatic cancer tissue (62.5%+/-4.1%) than in the adjacent pancreatic tissue (33.5%+/-2.8%, P<0.01). The degree of over-expression of beta-GCD was related to the degree of cancer cells differentiation, but not to the lymph nodes metastasis. The expression of TGF-beta1 was significantly correlated with the expression of beta-GCD in pancreatic cancer tissue. CONCLUSIONS: The genesis of pancreatic cancer results from multi-factor, multi-step and multi-gene variation. The synchronous detection of TGF-beta1 and beta-GCD helps to determine the malignant degree of tumors and the prognosis of patients with such disease.

Cell Differentiation↗

PubMed2002

[A 3D-rendering system for medical images based on COM].

This paper introduces a 3D medical image rendering system. The system uses the technology of COM with a fine upgradable and maintainable performances. Its main functions include image filtering, enhancement, image classification & segmentation, image registration, image interpolation and 3D display. The system can run on PC, so it owns a good practical value.

Algorithms↗

PubMed2001

Regulation of collagenase expression during replicative senescence in human fibroblasts by Akt-forkhead signaling.

The expression of collagenase (matrix metalloproteinase 1) in human fibroblasts increases during aging both in vivo and in vitro. This age-associated increase in collagenase expression has been postulated to contribute to the age related decline in tissue function by increasing proteolysis of matrix components, but little is known regarding the regulation of collagenase expression. We examined the role that the serine/threonine kinase Akt plays in collagenase expression during in vitro senescence of WI-38 normal human lung fibroblast cells. Our results indicate that Akt-mediated signals, acting through the forkhead transcription factor FKHRL1, can regulate collagenase expression in WI-38 fibroblasts. Dominant negative forms of Akt increase collagenase promoter activity in early passage WI-38 fibroblasts, whereas an active form of Akt suppresses steady state levels of collagenase mRNA in senescent WI-38 fibroblasts. In addition, the activity of a synthetic promoter containing forkhead-specific binding sites, as measured by luciferase activity, is much higher in senescent cells compared with early passage WI-38 fibroblasts. These results indicate that members of the forkhead family of transcription factors play a role in the regulation of the collagenase promoter and that increased activity of forkhead transcription factors may underlie the increase in collagenase expression observed during replicative senescence.

Binding Sites↗

PubMed2000

Cloning and Expression of Insulin Receptor Ligand-binding Domains.

Insulin receptor is a transmembrane protein consisting of four subunits, that form a heterotetramer(alpha(2)beta(2))with molecular weight of 350 kD. Because the extracellular subunit(alpha)consists of 731 residues and a cysteine-rich domain, it is difficult to express and crystallize such a large ligand-binding subunit, thus hampering further study on "insulin-receptor" complex. Based on the fact that the domains L1 and L2 of the alpha subunit, consisted of 119 and 118 residues, contained the high and low affinity insulin binding sites, respectively, the cDNAs of L1 and L2 were obtained from a human placental cDNA library by PCR. The cDNAs of L1, L2 and L1-(Ala)(10)-L2(designed ten-alanine-connected L1 and L2)were cloned, respectively, into an expression plasmid pET-3a, and E.coli BL21(DE3)transformants with such plasmids were successfully induced to express the goal proteins. The expression products were isolated and purified by the washing and solubilization of inclusion body, gel filtration chromatography and ion exchange chromatography. Each final product displayed a single band, corresponding the purity above 99%, in SDS-PAGE. These products have also been confirmed respectively as the L1, L2 and L1-(Ala)(10)-L2 by DNA sequencing, amino acid composition analysis and N-terminal amino acid sequencing.

Journal Article↗

PubMed2000

A Recombinant Monomeric Human Insulin Mutant with Resistance to Trypsin Design, Preparation and Characterization.

By using a gapped duplex DNA method, the four amino acids on the B chain of insulin, i.e. B22Arg, B28Pro, B29Lys and B30Thr, were mutagenized simultaneously into B22Asp, B28Lys, B29Pro and B30Lys, respectively. The recombinant B22Asp B28Lys B29Pro B30Lys human insulin was obtained simply by the treatment with trypsin of the precursor that was expressed in yeast. This human insulin analog had only 6% of receptor binding activity as that of the porcine insulin, but retained 50% of in vivo biological activity, compared with the latter. The self-association ability of the mutant measured through FPLC gel filtration chromatography showed that it was in monomeric state. As a monomeric insulin analog with resistance to the trypsin digestion, this compound may be promising in practical application.

Journal Article↗

PubMed2000

Possible Role of B8Gly in Insulin Structural Motif.

In the insulin structural motif n1-Cys-Gly-X10-Cys-n2-Cys-Cys-X3-Cys-X8-Cys-n3, there are seven absolutely conserved amino acid residues, and the only Gly is at position B8. When B8Gly was substituted with Ala by means of site-directed mutagenesis, a mutant insulin, [B8Ala]human insulin was obtained. The receptor binding capacity and in vivo biological activity of the [B8Ala]human insulin were about 2.5% and 10% of native porcine insulin, respectively. The far-UV circular dichroism (CD) spectra of [B8Ala]human insulin and human insulin showed that the relative content of alpha-helix in the mutant somewhat decreased. The results indicate that the B8Gly in the insulin structural motif is unreplaceble.

Journal Article↗

PubMed1999

Anisotropic Templating Effect in the Formation of Two-Dimensional Anionic Cadmium-Thiocyanate Coordination Solids [(12C4)(2)Cd][Cd(2)(SCN)(6)] and [(12C4)(2)Cd][Cd(3)(SCN)(8)] with Checkerboard and Herringbone Patterns, Respectively.

This paper reports the syntheses, characterization, and structures of two new two-dimensional cadmium-thiocyanate coordination solids [(12C4)(2)Cd][Cd(2)(SCN)(6)] (1) and [(12C4)(2)Cd][Cd(3)(SCN)(8)] (2), where 12C4 denotes 12-crown-4, C(8)H(16)O(4). 1 crystallizes in a monoclinic unit cell, space group C2/c with lattice parameters a = 16.297(3) Å, b = 26.267(3) Å, c = 16.296(2) Å, beta = 90.20(1) degrees, and Z = 8. 2 crystallizes in a monoclinic unit cell, space group P2(1)/n with lattice parameters a = 11.604(7) Å, b = 11.366(7) Å, c = 15.736(4) Å, beta = 92.84(3) degrees, and Z = 2. The structure of 1 exhibits a two-dimensional tetragonal motif consisting of Cd(2) units arranged in a checkerboard pattern with the dimeric [Cd(2)(SCN)(6)](2)(-) complex as the building block. The crystal structure of 2 can be described as a two-dimensional hexagonal array of linear trimeric Cd(3) units arranged in a herringbone pattern with the [Cd(3)(SCN)(8)](2)(-) complex as the building block. In both 1 and 2, the [(12C4)(2)Cd](2+) dications are housed in cavities within and between the anionic cadmium-thiocyanate layers but with different orientations ("upright" in 1 and "sideways" in 2) with respect to the cadmium-thiocyanate layers, giving rise to an anisotropic templating effect.

Journal Article↗