Biomedical subjects

G Yin

Publications and source records attributed to G Yin.

At least 19 recordsLinked to original sources

PubMed2006

Upregulation and activation of PKC alpha by ErbB2 through Src promotes breast cancer cell invasion that can be blocked by combined treatment with PKC alpha and Src inhibitors.

Although ErbB2 is known to enhance breast cancer metastasis, the signaling events responsible for this remain elusive. Alpha-isozyme of protein kinase C (PKCalpha), which is involved in cancer development and progression, has been suggested to be activated by ErbB2 without direct evidence. In addition, the roles of PKCalpha in ErbB2-mediated cancer cell malignancy have not been clearly identified. In this study, we investigated whether ErbB2 can activate PKCalpha and determined what role PKCalpha plays in ErbB2-mediated breast cancer cell invasion. We expressed wild-type and mutant ErbB2 with altered signaling capacities in MDA-MB-435 breast cancer cells and revealed that overexpression or activation of ErbB2 in MDA-MB-435 cells upregulated and activated PKCalpha and that downregulation of ErbB2 by small-interfering RNA decreased the expression and activity of PKCalpha in BT474 breast cancer cells. These in vitro results were supported by data from breast cancer patient samples. In 150 breast cancer tumor samples, ErbB2-overexpressing tumors showed significantly higher positive rates of PKCalpha membrane immunohistochemistry staining than that of ErbB2-low-expressing tumors. Mechanistically, we found that PKCalpha is co-immunoprecipitated with Src and PKCalpha expression and activity can be decreased by Src inhibitor PP2 and by the expression of a dominant-negative mutant of Src. Moreover, ErbB2-mediated upregulation of urokinase-type plasminogen activator receptor (uPAR) is reduced by either the PKCalpha inhibitor Go6976 or the Src inhibitor PP2, and the combination of Go6976 with PP2 is superior to either agent alone in suppressing uPAR expression and cell invasion. These results demonstrate that PKCalpha is critical for ErbB2-mediated cancer cell invasion and provide valuable insights for current and future PKCalpha and Src inhibitor clinical trials.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2006

Ethnic and geographical differences in systemic lupus erythematosus: an overview.

Systemic lupus erythematosus (SLE) is one of the most heterogeneous autoimmune disorders known. There is production of a variety of autoantibodies and patients present with a wide range of symptoms due to multiple organ involvement by the disease process. The underlying cause is not fully understood but it may involve genetic and environmental factors. It is interesting to note that while SLE is found worldwide, it is more commonly found in some countries, and within a country certain ethnic groups appear to be more susceptible to develop this condition than others. Additionally, the presentation and course of SLE appear highly variable between patients of different ethnic origins. For example, African-Americans and Orientals are believed to have a more severe disease than Caucasian whites. But are these ethnic and geographical differences real? If yes, they may provide investigators insight into the underlying pathoaetiology of this condition and pave the way to future research directions in lupus.

Anemia, Hemolytic, Autoimmune↗

PubMed2005

Variation of CD4+ and CD8+ T lymphocytes as predictor of outcome in renal allograft recipients who developed acute respiratory distress syndrome caused by cytomegalovirus pneumonia.

INTRODUCTION: We investigated the variation of CD4+ and CD8+ T lymphocytes in renal allograft recipients who developed acute respiratory distress syndrome (ARDS) caused by cytomegalovirus (CMV) infection and their relationship to patients outcome. METHODS: Twenty one cadaveric renal allograft recipients who developed ARDS caused by CMV infection were enrolled in this study. CD4+ and CD8+ T lymphocytes were examined in peripheral blood on five occasions: the admission day (day 0) to ICU as ARDS, day 5, day 10, day 15 in ICU, and discharge day. A value taken in the second month after transplantation was assumed to be the preinfection value. RESULTS: Among 13 surviving patients, the numbers of CD4+ and CD8+ T cells and their ratio increased as the patients recovered. The numbers of CD4+ T cells increased significantly on day 10, day 15, and at discharge day compared with day 0 (P < .05). The number of CD8+ T cells on discharge day and the ratios after day 10 were also significantly higher than those on day 0 (P < .05). In eight nonsurviving patients, the numbers of CD4+ and CD8+ T cells and their ratio was similar to day 0. The number of CD4+ and CD8+ cells after day 5 and their ratio after day 10 were significantly lower than those of survival group (P < .05). CONCLUSION: The variations of CD4+ and CD8+ T lymphocytes and their ratio are useful indicators of the severity of disease and the outcome of patients with CMV infections accompanying ARDS after renal transplantation. Nevertheless, it may be helpful to evaluate the efficiency of ongoing treatment methods in these patients.

CD4 Lymphocyte Count↗

PubMed2001

Oscillatory electroosmosis-enhanced intra/inter-particle liquid transport and its primary applications in the preparative electrochromatography of proteins.

The concept of generating an oscillatory electroosmotic flux inside the porous particle to enhance the intra-particle mass transport was presented and a new kind of electrochromatography carried out in a five-compartment electrolyzer were developed. The adsorbent was packed in the central compartment, while the neighboring compartments were used as the elution compartments and the electrode compartments, respectively. Chromatographic separations of human serum albumin on Blue Sepharose Fast Flow, bovine serum albumin (BSA) on DEAE-Sepharose Fast Flow, and BSA on hydroxyapatite were carried out, respectively. The adsorption isotherms were shown to be independent of electric field, while the increase in the electric field strength resulted in a linear increase in the magnitude of electroosmotic flux and the improvement of the breakthrough behavior in all cases. The experiment results have demonstrated the effectiveness of the oscillatory electroosmosis in enhancing intra- and inter-particle mass transport and its high potential to large-scale chromatography.

Adsorption↗

PubMed2001

Mass transport characteristics and chromatographic behavior of preparative electrochromatography on hydroxyapatite.

Introducing an electric field into chromatography on hydroxyapatite (HAP) was attempted in order to enhance mass transfer and separation performance. A membrane spaced multicompartment electrolyzer was developed for electrochromatography on HAP. The high performance of liquid transport by electroosmotic flux was identified and described in terms of dynamic electroosmotic pressure. The application of the electric field resulted in an improved adsorption of bovine serum albumin as shown by the breakthrough curve as function of the electric field. An improved elution was also obtained in the presence of the electric field. The results show that electroosmosis is a powerful tool of liquid transport and dispersion in a packed bed of fine particles and has potential in the large-scale chromatography of biological molecules.

Adsorption↗

PubMed2001

Laminar flow inhibits TNF-induced ASK1 activation by preventing dissociation of ASK1 from its inhibitor 14-3-3.

The inflammatory cytokine TNF-alpha stimulates several presumed pro-atherogenic signaling events in endothelial cells (ECs), including activation of c-Jun NH(2)-terminal kinase (JNK) and induction of E-selectin. Here, we show that apoptosis signal-regulating kinase 1 (ASK1), a MAP kinase kinase kinase, is required for TNF-mediated JNK activation. TNF activates ASK1 in part by dissociating ASK1 from its inhibitor 14-3-3. Because the risk of atherosclerosis is decreased in regions of steady laminar flow, we hypothesized that laminar flow inhibits proinflammatory cytokine-mediated activation of JNK. Steady laminar flow inhibited both TNF activation of ASK1 and JNK. Inhibition of ASK1 by flow correlated with increased association of ASK1 with 14-3-3. A constitutively active form of ASK1 lacking the 14-3-3-binding site (ASK1-Delta NS967A) was not inhibited by flow. These data establish ASK1 as a target for flow-mediated inhibition of cytokine signaling and indicate a novel role for 14-3-3 as an anti-inflammatory mediator in ECs.

14-3-3 Proteins↗

PubMed2001

[Effects of taurine on brain development and learning ability in filial mice fed with high iodine].

OBJECTIVE: To observe the effects of taurine on brain development and learning ability in filial mice fed with high iodine. METHODS: Mice were divided into three groups, the first one fed with adequate dose of iodine, the second with high-dose iodine, and the third with high-dose iodine plus 0.6% taurine. All the male and female mice were mated three months after treatment. Relevant biochemical indicators in the brain tissues and their memory and learning ability were measured for their offsprings with 30 days old in the three groups. RESULTS: Brain contents of protein and DNA reduced in the high-dose iodine group, and there was no significant difference in them between groups with taurine and adequate-dose iodine 30 days after their birth. Activity of acetylcholine esterase (ACHE) increased and content of acetylcholine decreased in the hippocampus of filial mice at age of 30 days with high-dose iodine. Content of acetylcholine increased in the filial mice with high-dose iodine plus taurine than that with adequate-dose iodine, but there was no statistically significant difference in ACHE between them. CONCLUSION: Taurine could antagonize disturbance of brain development in filial mice caused by high-dose iodine.

Animals↗

PubMed2001

[Study on preparation and properties of moisture permeable polyurethane membrane used for dressings].

A new hydrophilic polyurethane(PU) performed-polymer has been developed with polyethylene glycol(PEG) instead of general polyether. The solution of performed-polymer is poured casting a permeable membrane used for the outer layer of the bilayer dressings. The effects of molecular weigh (Mn) of PEG, the usage of cross-link agents, solvents and water in the solution on the moisture permeation of PU membrane have been studied. It has been shown that the membrane prepared is a porous moisture permeable membrane. The optimum conditions of preparing membrane are: Mn of PEG is 2,000-4,000, the mixture of acetone and N,N-dimethylformamide (DMF) is used as solvents, and the temperature of performance membrane is 50 degrees C-80 degrees C. The moisture permeability of the PU membrane is 49-60 g/m2.h at 35 degrees C, which can meet the requirement of the wound dressings. In addition, the mechanism of the moisture permeation of PU membrane has been discussed.

Bandages↗

PubMed2001

Cyclosporin A treatment for idiopathic membranous nephropathy.

OBJECTIVE: To evaluate the efficacy of cyclosporin A (CSA) in the treatment of idiopathic membranous nephropathy (IMN), a prospective controlled clinical study was performed. METHODS: This study included a group of 30 IMN patients, among them 15 were treated with CSA and 15 with captopril (CAP). The diagnosis of IMN was made with exclusion of secondary forms of membranous nephropathy by extensive clinical and pathological studies. No patients received steroids or cytotoxic agents for six months prior to enrollment. In the CSA group, CSA was given at an initial dosage of 5 mg.kg-1.d-1, gradually tailed off over the first three months and maintained at 2 mg.kg-1.d-1 for 12 months. In the CAP group, CAP was given at a dosage of 37.5 mg/day. RESULTS: In the first three months, 6 (6/15) complete remissions (CR) and 2 (2/15) partial remissions (PR) were observed in the CSA group while only 2 (2/15) PRs were observed in the CAP group. Before the end of the 15-months, 8 patients in the CSA group experienced CR and 4 patients experienced PR. One CR patient relapsed as the dosage of CSA was reduced, so 7 patients remained in CR at the end of the first 15-months. No additional CR or PR was observed in the CAP group during late follow-up. At the last visit (an average follow-up time of 44 months) in the CSA-group, another 2 CR patients had relapsed and 1 CR patient shifted to PR after stopping the CSA treatment, so 4 CR and 5 PR remained in the CSA group. In the CAP group, 3 spontaneous CRs occurred beyond 1.5 year's follow-up, with 3 CR and 2 PR at the last visit. No difference was found between the averages of the initial and the last serum creatinine levels in either group. No serious adverse effects were found during CSA treatment. Re-biopsy data of three patients responsive to CSA treatment showed that no pathological improvement of glomerular basement membrane was observed, even in cases at remission. Tubulointerstitial fibrosis was found in 1 relapsed CR patient, whose serum creatinine increased above the normal range, but not in the other 2 patients whose serum creatinine remained in the normal range. CONCLUSIONS: CSA therapy at a dosage of 5 mg.kg-1.d-1 is effective in inducing remission of nephrotic syndrome in adult IMN patients within three months, with a response rate of 80%. A relatively high rate of relapse (50%) was observed within 2 years after the withdrawal of CSA treatment.

Adult↗

PubMed2001

[Determination of chromosome of Gluconobacter oxydans SCB329].

After the pure culture of Gluconobacter oxydans SCB329 was researched, its growth curve was measured and its logarithmic phase was determined as between 4-24 h. After the microorganisms were havested in its logarithmic phase, The intact chromosome was prepared by agarose-embedded method. Then the genome of SCB329 was analyzed by Pulsed-field Gel Electrophoresis. The result indicated that there are one chromosome and one great plasmid. The length of intact chromosome of SCB329 has been estimated to be approximately between 2.2 Mb and 3.5 Mb.

Chromosomes, Bacterial↗

PubMed2001

[Studies on the genome size and structure of Gluconobacter oxydans SCB329].

In the "Two-step fermentation" of Vitamin C synthesis, Gluconobacter oxydans SCB329 is responsible for the production of 2-keto-L-gulonic acid (2-KLG), which is an important precuror of vitamin C synthesis. The intact chromosome was prepared from logarithmic phase cells by agaraseembedded method and was analysized by restriction endonucleases and contour-clamped homogeneous electric field pulsed-field gel electrophoresis (PFGE). Spe I (5-ACTAGT) produced 24 fragments, ranging in size from 10 to 320 kilobases (kb). Xba I (5-TCTAGA) yielded 40 fragments (4 to 200 kb). A total genome size of approximately 2,700 kb was determined by summing the fragment length. Analysis of the entire genome of SCB329 by PFGE revealed that the genome of SCB329 consist of a chromosome which is 2,500 Kb in length and a large plasmid which is 245 kb. After linearization of the DNA by DNase I and S1 nuclease, in contrast with the band which can not be viewed, the band of chromosome and plasmid were appeared, this suggest that structure of the chromosome and the plasmid were circular.

Chromosomes, Bacterial↗

PubMed2001

[Production of vitamin C precursor--2-keto-L-gulonic acid from D-sorbitol by mixed culture of microorganisms].

Gluconobacter oxydans SCB329 only produce a little amount of 2-Keto-L-gulonic acid(2-KLG) from D-Sorbitol when growing alone; while Gluconobacter sp. SCB110 can transform D-Sorbitol to L-Sorbose and can not produce 2-KLG. 2-Keto-L-gulonic acid, the precursor of L-Ascorbic acid (Vitamin C) synthesis, was prepared directly with a high efficiency from D-Sorbitol by mixed culture of microorganism, which comprised Gluconobacter sp. SCB110 and Gluconobacter oxydans SCB329. The fermentation product from the mixed culture broth in the D-Sorbotol-containing medium was identified as 2-Keto-L-gulonic acid by HPLC, elementary analysis and infra-red adsorption spectrum.

Coculture Techniques↗

PubMed2000

Geodetic evidence for a low slip rate in the Altyn Tagh fault system

The collision between India and Asia has been simulated with a variety of computational models that describe or predict the motions of the main faults of east Asia. Geological slip-rate estimates of 20-30 mm yr(-1) suggest that the largest of these faults, the 2,000-km-long Altyn Tagh fault system on the northern edge of the Tibetan plateau, absorbs as much of the Indo-Asian convergence signal as do the Himalayas--partly by oblique slip and partly by contraction and mountain growth. However, the predictions of dynamic models for Asian deformation and the lower bounds of some geological slip-rates estimates (3-9 mm yr(-1); refs 7, 8) suggest that the Altyn Tagh system is less active. Here, we report geodetic data from 89-91 degrees E that indicate left-lateral shear of 9 +/- 5 mm yr(-1) and contraction of 3 +/- 1 mm yr(-1) across the Altyn Tagh system. This result--combined with our finding that, at 90 degrees E, Tibet contracts north-south at 9 +/- 1 mm yr(-1)--supports the predictions of dynamic models of Asian deformation.

Journal Article↗

PubMed2000

[Study on statistical method of distribution for erythrocyte morphological features by computerized image processing].

This study sought to develop a new statistic method for the semiautomatic analysis and classification of erythrocyte morphology based on the morphological features and shape analysis of erythrocytes by computer image processing. Shape factor as the description of the erythrocyte morphological features was used for the shape classification of erythrocytes. And the models and algorithms of erythrocytes image segmentation, cell body shape recognition and measure can be implemented through the VC++. The present method can efficiently and semi-automatically provide the statistical analysis of erythrocyte morphology, and can give the distribution of erythrocyte morphological features. The result showed that there was a significant difference between the distribution curves of the normal erythrocyte morphology (one apex) and hemolytic anemia's (two apices). By this way, it can be obtained the proportion data of different cell bodies' shapes. This method could provide some information for the study and diagnosis of the diseases (e.g. hemolytic anemia, pre-leukemia) related to erythrocyte morphology.

Algorithms↗

PubMed2000

[Effect of Weikangfu granule on ultrastructure of gastric mucosa in patients of precancerosis with spleen deficiency syndrome].

OBJECTIVE: To observe the effect of Weikangfu Granule (WKFG) on the ultrastructure of gastric mucosa. METHODS: WKFG was used to treat 61 patients with gastric mucosa intestinal metaplasia or atypical proliferation, and histopathological and ultrastructural examination on gastric mucosa of antral region obtained through gastroscopy were conducted before and after treatment. RESULTS: After treatment, the histopathology and intestinal metaplasia subset of antral focal region, and the background lesion in ultrastructure of the mucosa in the nonfocal region were all improved in the 4 groups, The effects of Spleen-Qi Deficiency syndrome group and Spleen-Yang Deficiency group were superior to Ying-Deficiency group as well as Spleen-Deficiency and Qi-Stagnation group (P < 0.05, P < 0.01), and approached to those in the healthy control group. CONCLUSION: WKFG improves the quantitative balance of internal bioactive substances to maintain the homeostasis, promotes the ultrastructural normalization of mucosa so as to cure the clinical symptoms and reverse the intestinal metaplasia and atypical proliferation of mucosa.

Adult↗

PubMed2000

[Therapeutic effect of weikangfu on gastric precancerous disorder with spleen deficiency syndrome and its effect of gastric mucosal zinc, copper, cyclic adenosine monophosphate, superoxide dismutase, lipid peroxide and 3H-TdR lymphocyte conversion test].

OBJECTIVE: To observe the clinical therapeutic effect of Weikangfu granule (WKF) on intestinal metaplasia (IM), atypical proliferation (ATP) and its therapeutic mechanism. METHODS: Sixty-one patients (treated group) were diagnosed by integrated TCM and western medicine (WM), and treated according to Syndrome Differentiation, the amount of WKF was adjusted according to various Syndromes. The control group consisted of 54 patients, took Weisu granule without considering their Syndromes. Besides, 15 healthy subjects comprised of the control group. Gastroscopy was conducted both before and after the treatment, mucosal sample was taken from antral region of stomach for pathological changes, for IM classification through histochemical staining and for determination of gastric mucosal Zn, Cu, cAMP, SOD, serum LPO and 3H-TdR lymphocyte conversion test (LCT). RESULTS: (1) The symptomatic and pathologic therapeutic effect of the treated group were markedly better than those of the control group (P < 0.05, P < 0.01). (2) The levels of gastric mucosal Zn, Cu, cAMP, SOD and 3H-TdR LCT of the treated group before treatment were all lower than that of the healthy control group, but they were markedly increased after treatment, while serum LPO, however, increased before treatment, significant difference existed between the above groups (P < 0.05, P < 0.01). CONCLUSION: WKF can reverse IM and ATP of Spleen Deficiency Syndrome through the mechanism of improving the level of gastric mucosal Zn, Cu, cAMP and SOD, promoting cytodifferentiation, improving cytoimmunity, reducing superoxide and LPO.

Adult↗

PubMed2000

[Effects of excessive iodine on activity of enolase in hippocampus of developing mice].

OBJECTIVE: To study the effects of excessive intake of iodine for a long term on activity of enolase in hippocampal tissues of young mice. METHODS: A hyperiodine goiter animal model was replicated with drinking water with high level of iodine. Activity of neuron specific enolase (NSE) in hippocampal tissues was determined with enzyme-linked immunosorbent assay (ELISA) for young offspring of the first and the second generations of mice with hyperiodine goiter on the 7th, 14th and 21st day of age, respectively. RESULTS: Activity of enolase in young offspring of the first and second generation of mice with hyperiodine goiter was all lower than that in controls from the day of their birth to the 30th day after birth, and that at hippocampal tissues in young mice of the second generation was significantly lower than that of the first generation on the 14th day of age. CONCLUSION: Hyperiodine can decrease activity of NSE in the brain of mice. It suggests that hyperiodine can affect NSE, and thus interfere energy supply in the brain, resulting in disturbance of neuron development and brain function.

Animals↗

PubMed2000

[Effects of excessive iodine on apoptosis and expression of bcl-2, bax genes in the cells of brain and thyroid gland in guinea pigs].

OBJECTIVE: To investigate the effects of excessive iodine intake on apoptosis and the expression of bcl-2, bax genes in the cells of brain and thyroid gland. METHODS: Guinea pigs, divided into two groups at random, were fed with distilled water containing iodine 50 microg/L (a control group with appropriate iodine) and 10,000 microg/L (a trial group with excessive iodine), respectively for six months. Apoptosis rate and expression of bcl-2, bax gene in the cells of cerebral cortex, hippocampus and thyroid gland in guinea pigs were quantitatively determined by flow cytometry and immunofluorescent techniques. RESULTS: The proportion of apoptosis in the cells of cerebral cortex, hippocampus and thyroid gland was significantly higher in the group with excessive iodine intake than that in the control one (P < 0.01). The level of expression of bcl-2 gene was notably decreased (P < 0.05), but that of bax was notably increased (P < 0.01), in the cerebral cortex, hippocampus and thyroid gland in the group with excessive iodine than in the control one. The ratio of bcl-2 to bax in the cerebral cortex, hippocampus and thyroid gland of the group with excessive iodine was decreased significantly (P < 0.01) than that of the control one. CONCLUSION: Excessive iodine intake may induce apoptosis in the cells of cerebral cortex, hippocampus and thyroid gland. The over-expression of bax gene and the down-regulation of bcl-2, which can then cause the decrease in a ratio of bcl-2 to bax, appear to play an important role in the course of apoptosis induced by excessive iodine intake.

Animals↗