Biomedical subjects

Jian-Hua Zhang

Publications and source records attributed to Jian-Hua Zhang.

At least 19 recordsLinked to original sources

PubMed2006

Adaptive regularization network based neural modeling paradigm for nonlinear adaptive estimation of cerebral evoked potentials.

In this paper we report an adaptive regularization network (ARN) approach to realizing fast blind separation of cerebral evoked potentials (EPs) from background electroencephalogram (EEG) activity with no need to make any explicit assumption on the statistical (or deterministic) signal model. The ARNs are proposed to construct nonlinear EEG and EP signal models. A novel adaptive regularization training (ART) algorithm is proposed to improve the generalization performance of the ARN. Two adaptive neural modeling methods based on the ARN are developed and their implementation and performance analysis are also presented. The computer experiments using simulated and measured visual evoked potential (VEP) data have shown that the proposed ARN modeling paradigm yields computationally efficient and more accurate VEP signal estimation owing to its intrinsic model-free and nonlinear processing characteristics.

Algorithms↗

PubMed2006

Cytotoxicity of HSVtk and hrTNF-alpha fusion genes with IRES in treatment of gastric cancer.

The efficacy of the suicide gene therapy by using the herpes simplex virus thymidine kinase/ganciclovir (HSVtk/GCV) system for the treatment of cancer is limited because of the insufficient gene transfer and the low killing activity. To enhance the anti-tumor activity, we probed into whether recombinant retroviral expression vector PLXSN expressing both HSVtk and TNF-alpha genes could potentiate the destruction of SGC7901. The pL(tk-TNF-alpha)SN harboring HSVtk and TNF-alpha genes in sequence was constructed with a bicistronic unit including the internal ribosomal entry site, the recombinant retroviruses were transferred into SGC7901 cells by lipofectamine, and pEGFP and Western blot analysis were used to detect the expression of fusion genes in transfected SGC7901 cells, and then apoptosis of the transfected cells were detected by using the TdT-mediated dUTP nick end labeling, flow cytometric analysis and transmission electron microscopy. In vitro study, the transfected gastric cancer cells were maintained in the GCV-contained medium, to assay the cell killing effect and bystander effect. In vivo experiments, retroviral serum plasmids were transfected into tumor-bearing nude mice, to observe the changes of tumor volumes and survival of the mice. In vitro there was no significant difference of cell survival rate between the three groups. However, in vivo results showed that tk/GCV, tk-TNF-alpha/GCV and TNF-alpha could inhibit the tumor growth, and the obvious anti-tumor effect was shown in tk-TNF-alpha/GCV group, and TNF-alpha obviously enhanced the anti-tumor effect in vivo. The pathologic examination showed necrosis of the cancer in the treated groups.

Animals↗

PubMed2006

In vitro effects of recombinant zebrafish IFN on spring viremia of carp virus and infectious hematopoietic necrosis virus.

In order to evaluate the effects of fish recombinant interferon (rIFN) on fish pathogenic rhabdoviruses, the zebrafish (Danio rerio) IFN (DreIFN) allele B gene was cloned and expressed in Escherichia coli. In addition, the effects of recombinant DreIFN (rDreIFN) on spring viremia of carp virus (SVCV), infectious hematopoietic necrosis virus (IHNV), and vesicular stomatitis virus (VSV) were surveyed in fish and chicken cells. The mature peptide of DreIFN allele B gene encodes 163 amino acids. Residues 3 and 98 are a pair of cysteines that likely form an intrachain disulfide bridge. rDreIFN protein was detected as a band at 21.6 kDa by SDS-PAGE. The purified rDreIFN has anti-SVCV and anti-IHNV activity of 3 x 10(4) U/mg-10(7) U/mg. The results indicate that rDreIFN has higher activity against SVCV and IHNV on epithelioma papulosum cyprinid (EPC) than on grass carp (C. idellus) ovary (CO) cell lines and no activity against VSV on chick embryo fibroblasts (CEF).

Amino Acid Sequence↗

PubMed2006

Prostate androgen-regulated gene: a novel potential target for androgen-independent prostate cancer therapy.

AIM: To investigate the involvement of the prostate androgen-regulated (PAR) gene in the androgen receptor (AR) signaling pathway and the malignant phenotype of androgen-independent prostate cancer (PCa) cells. METHODS: The difference in PAR expression between LNCaP and PC3 cells was detected by reverse transcription-polymerase chain reaction (RT-PCR). Androgen and anti-androgen effects on PAR expression were evaluated by RT-PCR in LNCaP, PC3 cells and PC3 cells stably transfected with vector containing wild-type AR. To determine the importance of PAR in the malignant proliferation of androgen-independent PCa cells, we used small interfering RNA (siRNA) transfection to knock down the expression of the gene in PC3 cells. The changes in the malignant phenotype of PCa cells after transfection were analyzed by cell count, colony formation in soft agar and flow cytometry. RESULTS: PAR expression was 3-fold higher in PC3 cells than that in LNCaP cells. Dihydrotestosterone (DHT) regulated PAR mRNA expression in LNCaP cells and the effect was inhibited by the AR antagonist, flutamide. By contrast, DHT did not affect PAR expression in PC3 cells. The reintroduction of AR into PC3 cells by stable transfection restored the androgen effect on PAR upregulation. After the knockdown of the PAR gene by siRNA, PC3 cells exhibited a reversal of the malignant phenotype. CONCLUSION: Because of the possibility that PAR is downstream from the AR, and because of its contribution to malignant proliferation in androgen-independent PCa cells, the gene could be a potential therapeutic target for androgen-independent PCa with AR signaling pathway alteration.

Base Sequence↗

PubMed2006

ZO-1 expression and phosphorylation in diabetic nephropathy.

Cellular mechanisms responsible for the loss of capillary wall permselectivity in diabetic nephropathy are not well characterized. ZO-1 is a junctional protein involved in the assembly and proper function of a number of tight junctions and is also expressed at the junction of podocytes with the slit diaphragm. We investigated the effect of diabetes and high glucose concentration on the expression of ZO-1 in animal models of both type 1 and 2 diabetes and in rat glomerular epithelial cells. In diabetic animals, immunohistochemistry and Western blotting showed decreased expression of ZO-1 in glomeruli. Immunogold electron microscopy revealed redistribution of ZO-1 from the podocyte membrane to the cytoplasm in the diabetic animals. Exposure of rat glomerular epithelial cells to high glucose resulted in a decrease in the intensity of ZO-1 staining and redistribution of ZO-1 from the membrane to the cytoplasm, changes that are attenuated by blockade of the angiotensin II type 1 receptor. ZO-1 protein expression and serine and tyrosine phosphorylation of ZO-1 were also decreased in cells exposed to high glucose. These findings suggest that alterations in the content and localization of ZO-1 may be relevant to the pathogenesis of proteinuria in diabetes.

Animals↗

PubMed2006

[Effects of PTEN gene transfection on proliferation and invasion of human bladder cancer cell line BIU87].

BACKGROUND & OBJECTIVE: PTEN (phosphatase and tensin homologue deleted from chromosome 10) is the first antioncogene with phosphatase activity till now, and was found absent or mutational in many primary malignant tumors and cell lines. Its inactivation is correlated to tumor development and prognosis. This study was to investigate the effects of PTEN transfection on proliferation and invasion of human bladder cancer cell line BIU87. METHODS: A eukaryotic expression plasmid containing PTEN, pBp-PTEN, was introduced into E. coli DH5alpha and amplified. The plasmid was prepared and purified, and then identified by restrictive enzyme digestion. pBp-PTEN was transfected into BIU87 cells, and positive cell clones (pBp-PTEN-BIU87) were selected and amplified. Empty plasmid-transfected BIU87 cells (pBp-BIU87) and normal BIU87 cells were set as control. The expression of PTEN was detected by reverse transcription-polymerase chain reaction (RT-PCR). Proliferation and invasion ability of BIU87 cells were measured before and after transfection by MTT assay and cell invasion assay. RESULTS: Plasmid pBp-PTEN containing PTEN was successfully constructed and transfected into BIU87 cells. After transfection, the inhibitory rates of cell growth at the first, second, third, and fourth days were 4.27%, 18.92%, 19.54%, and 17.69%, respectively. The penetrating cells were significantly less in pBp-PTEN-BIU87 group than in pBp-BIU87 and BIU87 groups (39.3+/-7.7 vs. 48.1+/-13.2 and 48.9+/-11.0, P<0.05). CONCLUSION: Transfection with PTEN might suppress proliferation and invasive ability of bladder cancer BIU87 cells.

Cell Line, Tumor↗

PubMed2006

[Preliminary application on test paper of gold-labelled antibody against fibronectin EIIIA splicing variant].

OBJECTIVE: To develop the test Paper of gold-labelled antibody against fibronectin EIIIR A splicing variant, which can be available in forensic wound interval estimation. METHODS: Two sensitive antibodies were compared with enzyme link immunoabsorband assay (ELISA). After colloid gold labeled, the effects of the two antibodies were tested by methods of Dot immunogold filtration assay and gold immunochromatography assay, respectively. The test paper was finally appraised by applied in experimental skin injury in rats. RESULTS: On the test paper, detected line appeared in three hours wound age group, and then the darkness of positive staining became darker with injury time prolonging, while control normal skin cannot found to be positive staining. CONCLUSION: The gold-labeled test paper can be useful in estimation of wounding interval in forensic science.

Alternative Splicing↗

PubMed2006

[Validation studies of the test strip of colloidal gold-labeled anti-fibronectin EIIIA splicing variant for estimating the time of injury].

OBJECTIVE: To evaluate the validation of the test strip of colloidal gold-labeled anti-Fibronectin EIIIA(Fn-EIIIA) Splicing Variant for estimating the time of injury. METHODS: After skin tissues with variant injury times were collected from corpses, the test strip were used to detect the expression of Fn-EIIIA and its tested results were valued; The arisen autolysis which may influence the results of test were also observed by rats models. RESULTS: In no-injured skins, no Fn-EIIIA were detected by the strip, while in all the injured skins it was detected successfully as soon as injured after 1h and it showed more obvious results with the elongating of injured time; No changes made by autolysis were found in our studied time ranges. CONCLUSION: The test strip which used in this study showed to be a sensitive and steady method for estimating the time of injury in forensic science.

Alternative Splicing↗

PubMed2006

[Effect of bacillus calmette-guerin treatment on airway inflammation and T regulatory cells in mice with asthma].

OBJECTIVE: Previous studies have shown that bacillus calmette-guerin (BCG) can deviate TH2 response toward TH1 response, resulting in a suppressive effect on the development of asthma/atopy. This study examined the effect of BCG treatment on regulatory T cells in asthmatic mice to investigate the possible mechanism. METHODS: Kunming mice were sensitized and challenged with ovalbumin (OVA) to establish asthmatic models. Asthmatic mice were injected intradermally with BCG five days before and after sensitization. After 24 hrs of last challenge, bronchoaveolar lavage fluid (BALF) and peripheral blood were collected . The total cells and eosinophils were counted in the BALF. The percentage of CD4(+) CD25(+) in peripheral blood was detected with flow cytometry. Single spleen cell suspension was prepared and cultured in 1640 medium for 48 hrs and then the cytokine IL-10 level in the supernatant was determined using ELISA. The mice which were challenged with normal saline were used as the Normal control group. RESULTS: The number of total cells and eosinophils in BALF in asthmatic mice [(27.27 +/- 5.36) x 10(7)/L and (6.59 +/- 1.32) x 10(7)/L respectively] were more than in the Normal control group [(1.52 +/- 0.36) x 10(7)/L and zero respectively] (P < 0.01). The number of total cells and eosinophils in BALF in asthmatic mice were reduced after BCG treatment [(13.71 +/- 3.17) x 10(7)/L and (1.43 +/- 0.37) x 10(7)/L respectively] (P < 0.01). The percentage of CD4(+) CD25(+) in peripheral blood of asthmatic mice [(11.59 +/- 1.33)%] was noticeably lower than that of the Control group [(13.66 +/- 1.68)%] (P < 0.01), but increased significantly in asthmatic mice after BCG treatment [(14.40 +/- 2.70)%] (P < 0.05). The IL-10 level in spleen cell supernatant in the BCG-treated group (7.79 +/- 1.34 pg/mL) also increased compared with that in the untreated asthmatic mice (5.54 +/- 0.66 pg/mL) (P < 0.01). CONCLUSIONS: BCG can markedly inhibit the airway inflammation in asthmatic mice possibly by promoting the production of regulatory T cells.

Animals↗

PubMed2005

Age-related changes in cholinergic neurons in the laterodorsal and the pedunculo-pontine tegmental nuclei of cats: a combined light and electron microscopic study.

In aged cats, light microscopic studies revealed significant decrease in the soma size of choline acetyltransferase (ChAT)-positive neurons in the laterodorsal and pedunculo-pontine tegmental nuclei (LDT and PPT), compared with adult control animals. In addition, a significant reduction of the total dendritic length and total dendritic segment number of ChAT-positive neurons was detected in both the LDT and PPT of aged cats. However, in contrast to the changes of soma and dendrites, no significant changes in the number of ChAT-positive neurons in aged were found comparing to that in the control cats in both the LDT and PPT; nor were there differences in the staining intensity of the somata of neurons in the adult and aged cats. Electron microscopic analysis highlighted degenerative changes in cholinergic neurons in the LDT and PPT of aged cats which included somata with intracytoplasmic vacuoles, darkened mitochondria, depletion of dendritic microtubules and severe demyelination of axons. These data indicate that profound atrophic changes occur in cholinergic systems of the LDT and PPT as a consequence of the aging process. These alterations likely reflect the cellular bases for the age-related changes in REM sleep that occur in old animals.

Age Factors↗

PubMed2005

Age-related changes of hypocretin in basal forebrain of guinea pig.

Hypocretin-1 (hcrt-1) and hypocretin-2 (hcrt-2) have been implicated in a wide variety of functions including sleep and wakefulness as well as related behaviors. Many of these functions of the hypocretins involve the activation of cholinergic neurons in the basal forebrain (BF). These neurons have been shown to exhibit age-related changes in a variety of species. In the present experiment, in adult and aged guinea pigs, we compared hypocretin immunoreactivity in regions of the BF that include the medial septal nucleus (MS), the vertical and horizontal limbs of the diagonal band of Broca (VDB and HDB) and the magocellular preoptic nucleus (MCPO). In adult guinea pigs (3-5 months of age), all of the preceding BF regions contained dense hypocretin fibers with varicosities. On the contrary, in old guinea pigs (27-28 months), although the MS exhibited a similar intensity of hypocretin immunoreactivity compared with the adult guinea pig, there was a significant decrease in the intensity of immunoreactivity of hypocretinergic fibers in the VDB, HDB and MCPO. These data indicate that the hypocretinergic innervation of specific nuclei of the BF is compromised during the aging process. We suggest that the reduction in hypocretinergic innervation of the BF nuclei may contribute to the age-related changes in the states of sleep and wakefulness as well as deficits in related systems that occur in old age.

Aging↗

PubMed2005

topors, a p53 and topoisomerase I-binding RING finger protein, is a coactivator of p53 in growth suppression induced by DNA damage.

The RING family zinc-finger protein topors (topoisomerase I-binding protein) binds not only topoisomerase I, but also p53 and the AAV-2 Rep78/68 proteins. topors maps to human chromosome 9p21, which contains candidate tumor suppressor genes implicated in small cell lung cancers. In this study, we isolated the murine counterpart of topors and investigated its impact on p53 function. The deduced amino-acid sequence of mouse topors exhibits extensive similarity to human topors. Overexpressed myc-tagged topors associates with and stabilizes p53, and enhances the p53-dependent transcriptional activities of p21(Waf1), MDM2 and Bax promoters and elevates endogenous p21(Waf1) mRNA levels. Overexpression of topors consequently results in the suppression of cell growth by cell cycle arrest and/or by the induction of apoptosis. Taken together, these studies identify topors as a positive regulator of p53. The expression of topors is induced by exposure to the genotoxic reagents cisplatin and camptothecin, a DNA topoisomerase I inhibitor. We therefore postulate that topors mediates p53-dependent cellular responses induced by DNA damage, suggesting its physiological role as a tumor suppressor.

Amino Acid Sequence↗

PubMed2005

Parafibromin, product of the hyperparathyroidism-jaw tumor syndrome gene HRPT2, regulates cyclin D1/PRAD1 expression.

Parafibromin is the 531-amino-acid protein product encoded by HRPT2, a putative tumor suppressor gene recently implicated in the autosomal dominant hyperparathyroidism-jaw tumor familial cancer syndrome, sporadic parathyroid cancer, and a minority of families with isolated hyperparathyroidism. Parafibromin contains no identified functional domains but bears sequence homology to Cdc73p, a budding yeast protein component of the RNA polymerase II-associated Paf1 complex. This study addressed the expression and functional properties of human parafibromin. A survey of human and mouse tissues analysed with polyclonal antibodies to parafibromin showed specific immunoreactivity in adrenal and parathyroid glands, kidney, heart, and skeletal muscle. Subcellular fractionation and laser confocal microscopy of normal human parathyroid gland demonstrated expression of parafibromin in both the cytoplasmic and nuclear compartments. Parafibromin was expressed in four parathyroid adenomas but was absent from two parathyroid carcinomas. Transient overexpression of wild-type parafibromin, but not its Leu64Pro missense mutant implicated in parathyroid cancer and familial isolated hyperparathyroidism, inhibited cell proliferation, and blocked expression of cyclin D1, a key cell cycle regulator previously implicated in parathyroid neoplasia. These results demonstrate that human parafibromin is a nucleocytoplasmic protein with functions consistent with its postulated role as a tumor suppressor protein.

Adenoma↗

PubMed2005

Age-related ultrastructural changes in hypocretinergic terminals in the brainstem and spinal cord of cats.

In a previous study, we noted the presence of enlarged "spot-like" structures that are immunoreactive to hypocretin in specific regions of brainstem of aged cats; similar structures were not seen in the same regions of adult cats. In the present study, electron microscopy was combined with hypocretin immunohistochemistry to examine the ultrastructure of these enlarged "spot-like" structures, which were found to consist of enlarged axonal terminals. The terminals were comprised of a large pale core with a dark peripheral rim. Many granules were present within the core; most of these granular structures were not immunostained. On the other hand, the rim contained a high density of hypocretin immunoreactivity; in this peripheral region, large dense-core vesicles and small synaptic vesicles without dense cores were observed. In addition, mitochondria in the peripheral rim region exhibited high electron density, which is indicative of the presence of age-related degenerative changes. Synaptic contacts were observed between the enlarged terminals and adjacent dendrites. Most of these synapses were asymmetric (Gray type I), although a few of them were symmetric (Gray type II). These data suggest that hypocretin transmission is altered during aging, which would be expected to result in age-related changes in the functioning of the hypocretinergic system.

Aging↗

PubMed2005

Possible mechanism of referred pain in the perineum and pelvis associated with the prostate in rats.

PURPOSE: Since persistent pain in the perineum and pelvic floor associated with chronic prostatitis /chronic pelvic pain syndrome has been hypothesized to be referred pain, it might also be explained by neural mechanisms. MATERIALS AND METHODS: Dual retrograde fluorescent labeling and immunohistochemistry were identified as methods with which to investigate the neurogenic aspect of this status. The dual distribution of dorsal root ganglia (DRG) cells was determined after double retrograde fluorescent staining of the prostate and pelvic floor, and the prostate and perineum somatic nerves. Calcitonin gene-related peptide (CGRP) and substance P (SP) in dual labeled cells were determined by immunohistochemistry, giving possible insight into the cause of pelvic pain. RESULTS: Fluorescent double labeled cells were found in the lumbar and sacral DRG, while double labeled cells were distributed predominantly in L6 to S1 and L1 to L2 segment DRG in groups 1 and 2, respectively. On immunohistochemistry some of them were confirmed to contain CGRP and SP. Thus, there are crossover pathways between the prostate and pelvic floor. CONCLUSIONS: The findings that we present confirm that the peripheral process of DRG cells dichotomizes to the prostate, sphincter and somatic parties simultaneously. Some of these cells contain CGRP and SP, which indicate that referred pain in the perineum and pelvic floor may be caused by an axon reflex in the peripheral process of DRG neurons.

Animals↗

PubMed2005

Measuring blood flow velocities based on three image processing techniques.

The classification of microcirculation can be based on the size of the capillary and the velocity of the blood flow. For each type of microcirculation, the ad hoc method is required to measure the blood flow velocity. In this paper, the correlation method is used to measure blood flow velocity in the small-size capillary. The large-size capillaries are classified into three types based on the blood velocities, say low-speed, high-speed, and unstable one. The template-matching algorithm, the Fast Fourier Transform algorithm and a high-speed video camera measurement are used to measure the blood velocities corresponding to those three types of large-size capillary. It was shown by several experiments that fairly good results for different types of capillary may be obtained by using the proposed three image processing algorithms.

Algorithms↗

PubMed2005

A nonlinear adaptive fuzzy approximator technique with its application to prediction of non-stationary EEG dynamics and estimation of single-sweep evoked potentials.

In this paper, we apply a fast training paradigm to the optimization of fuzzy approximator and a nonlinear adaptive fuzzy approximator (NAFA) is constructed. Using TSK fuzzy rules, the structured knowledge along with numerical information are parameterized and utilized in the NAFA, which can be easily configured as a multi-layer network when its transparency is desired. We propose a fast training paradigm, which is actually a combination of Kalman filtering and LMS adaptation, to optimize the linear and nonlinear parameters of the NAFA separately. The NAFA is characterized by concise representation of structured knowledge, fast learning capability, as well as universal approximation property. The NAFA is applied to forecast the non-stationary EEG time-series and to estimate single-sweep evoked potentials (EPs). The corresponding simulation results are given. It is concluded that the NAFA technique can provide efficient nonlinear separation of single-sweep EPs, which allows for quantitative examination of the cross-trial variability of clinical EPs.

Artifacts↗

PubMed2005

[Analysis of correlative factors affecting IIEF-5 scores of type 2 diabetic patients].

OBJECTIVE: To investigate the correlative factors affecting the IIEF-5 scores of the patient with type 2 diabetic mellitus (T2DM). METHODS: A total of 149 T2DM patients were investigated for the relationships between their IIEF-5 score and such factors as age, body mass index (BMI), fasting plasma glucose (FPG), 2hPG, insulin (INS), GHbA1c, C-peptide, nitric oxide (NO), testosterone (T), estradiol (E2), the ratio of testosterone to estradiol (T/E), erythrocyte aldose reductase (AR), drinking, smoking, concomitant diseases, complications and medication. RESULTS: The scores of the groups of smoking, complication, medication and concomitant disease were significantly lower than those of the controls. There was significant negative correlation between IIEF-5 scores and age, BMI, FPG, 2hPG, INS, GHbA1c and AR (P < 0.05), and significant positive correlation between IIEF-5 scores and NO (P < 0.05). But there was no correlation between drinking, T, E2 and T/E2 (P > 0.05). CONCLUSION: Many factors may affect the IIEF-5 scores of T2DM patients.

Adult↗