Biomedical subjects

Ning Liu

Publications and source records attributed to Ning Liu.

At least 73 records · Page 4Linked to original sources

PubMed2005

[The function of ERK on Fas-mediated apoptotic signaling pathway of human gastric carcinoma cells].

OBJECTIVE: To analyze the expression and functions of ERK (extracellular regulated kinase) in Fas-mediated apoptosis in gastric carcinoma cell line SGC-7901 and to elucidate the potential significance of this signaling pathway in tumor progression. METHODS: Radioisotope labeling and Western blotting with special anti-ERK antibody were used to check ERK activity in SGC-7901 cell line after anti-Fas antibody treatment. Apoptosis induced by several treatment factors was evaluated by FACS can flow cytometer. RESULTS: ERK activity increased and reached the peak at 30 min after treatment with anti-Fas antibody and decreased in PD98059 pretreated group. The number of sub-G(1) cell was 30.5% +/- 2.6% in PD98059 pretreated group, which was higher than anti-Fas treatment group and control group, respectively. CONCLUSION: In gastric cancer cell line SGC-7901, Fas-induced ERK activation may suppress Fas-mediated apoptosis. Inhibition of ERK may enhance the sensitivity of SGC-7901 cells to Fas-mediated apoptosis. Fas-induced ERK activation may confer gastric cancer cells ability to escape the immune surveillance.

Apoptosis↗

PubMed2005

[Surgical management of old vertical unstable pelvic fractures].

OBJECTIVE: To study the therapeutic effect of open reduction and internal fixation in the management of old vertical unstable pelvic fractures. METHODS: In the 9 cases with surgical treatment for pelvic fractures, combination of the anterior and posterior approaches was adopted. RESULTS: In the follow-up lasting for 6-30 months, all pelvic fractures were reduced satisfactorily. The 9 patients were able to walk and 8 of them gained good clinical recovery without complications. CONCLUSION: In the management of old vertical unstable pelvic fractures, a stable pelvis can be reconstructed by effective open reduction and internal fixation through combination of the anterior and posterior approaches, so that further sequelae can be reduced.

Adult↗

PubMed2005

[Magnetic properties and transport behaviors in double doped La(0.67+1.33x)Sr(0.33-1.33x)Mn(1-x)Mg(x)O3 system].

The M-T curves, M-H curves, ESR curves, infrared spectrum, Raman spectrum, rho-T curves and MR-T curves of La(0.67+1.33x)Sr(0.33-1.33x)Mn(1-x)Mg(x)O3 (0.00 < or = x < or = 0.25) were studied. The experiment pointed out that all samples exhibit a paramagnetic-ferromagnetic (PM-FM) transition associated with metallic-insulating (MI) transition in the low doping region, which does not occur in the heavy doping zone. The authors suggest that this behavior is attributed to the difference between the Jahn-Teller distortion of the Mn3+ ion neighboring Mg2+ and that of the Mn3+ ion non-neighboring Mg2+, which is confirmed by the IR and Raman spectra. The anomalous transport behavior is dominated by the differerent Jahn-Teller distortion.

Electron Spin Resonance Spectroscopy↗

PubMed2005

[Clinical value of ultrasound guided transperineal prostate biopsy in detecting prostate cancer].

OBJECTIVE: To report our experience of ultrasound guided transperineal 6-core prostate biopsy (UG6CPB) in the diagnosis of prostate cancer (PCa). METHODS: In a prospective study, we performed UG6CPB in 104 suspected PCa patients with tPSA more than 4 microg/L and analysed the positive rate and complications of the diagnostic approach. RESULTS: PCa was detected in 24 of the 104 patients (23%), with low grade Gleason 2 to 4 in 3 cases (12.5%), intermediate grade Gleason 5 to 7 in 15 (62.5%) and high grade Gleason 8 to 10 in the remaining 6 (25%). Complications included temporary hematuria in 5 patients (4.8%), mild postbiopsy perineal discomfort in 5 (4.8%) and fever in 4 (3.8%). TPSA > or =10 microg/L, fPSA > or = 2 microg/L, fPSA/tPSA < 0.16, PSAD > or = 0.2 and prostate volume < 40 ml were the significant influencing factors of biopsy positive rate (P < 0.05). CONCLUSION: UG6CPB is an exact and a safe way of detecting PCa.

Biopsy, Needle↗

PubMed2005

[Determinants of long-term survival in 38 patients with carcinoma of ampulla of Vater treated by local resection].

OBJECTIVE: To investigate determinants of long-term survival for carcinoma of ampulla of Vater treated by local resection. METHODS: The clinical and pathological data of 38 such patients treated by local resection from 1983 to 2003 were retrospectively analyzed. According to UICC staging system, there were T1 30, T2 7 and T3 1. Lymph nodes were involved in 4 during operation which was present in primary lesions larger than 2 cm across. All patients were treated by local resection. At first, external palpation was carried out to ascertain accessibility. Then with the duodenum opened, direct exploration was carried out. On deciding for resection, the common bile duct was probe explored which guided the circumferential ring resection 1 cm, away from the tumor, including all layers of duodenum, ampula and partial bile and terminal pancreatic ducts and the posterial wall of duodenum was completed in steps. Meticulous care was taken not to suture the pancreatic duct and endotheliation was ensured at the mouth of common bile duct and duodenum. The basal tissue was frozen sectioned to ensure negative stumps. The gall bladder of 6 patients was also resected. SPSS 10.0 software was used in data processing, log-rank test used in univariate analysis and Cox equation for multivariate analysis and Kaplan-Meirer method for the survival rates. RESULTS: Thirty-eight patients received local resection giving an operative mortality of 0% and morbidity of 13.2%. The 1-, 5- and 10-year survival rate was 83.5%, 51.4%, and 38.9%, respectively, with a median survival of 3.35 years. Up to now, 13 patients have survived for more than five years and 2 patients beyond ten years. The tumour size, tumour grading, lymph node status and UICC stage were significant prognostic factors in univariate analysis. However, only lymph node status was a statistically independent predictor of prognosis in multivariate analysis. CONCLUSION: Local excision is safe giving low morbidity and good survival in carefully selected cases. Preferably it is indicated only in high risk patients with a pT1 and well differentiated ampullary cancer smaller than 1 cm in diameter.

Adenocarcinoma↗

PubMed2004

[The methods of shorting of proximal femoral and total hip arthroplasty for old femoral neck fracture with severe hip joint dislocation].

OBJECTIVE: To discuss the effective method and outcome to old femoral neck fracture with severe hip joint dislocation. METHODS: From April 1996, 7 cases of old femoral neck fracture with severe hip joint dislocation were treated by the shorting of posterior femoral and total hip arthroplasty. RESULTS: The average age of 7 patients was 51 years old and the mean follow-up was 27.3 months. The mean Harris score was improved to 84.3 from 36.7 before operation in the latest follow-up. The prosthesis position of acetabular and femoral was excellent, there was no sinking or softening of artificial joint, nonunion of femoral osteotomy. CONCLUSION: The preliminary clinical results are quite satisfactory of the shorting of posterior femoral and total hip arthroplasty to old femoral neck fracture with severe hip joint dislocation, the follow-up is necessary for further long-term outcome.

Adult↗

PubMed2004

Age-related effects of bilateral frontal eye fields lesions on rapid eye movements during REM sleep in rhesus monkeys.

Rapid eye movement (REM) is one of the most characteristic features of REM sleep, but the mechanisms underlying its regulation remain unclear. The present study aims to investigate whether the frontal eye field (FEF) is involved in the regulation of the rapid eye movements during REM sleep. To address this question, we ablated the FEF in four rhesus monkeys and observed the effects of the lesions on sleep architecture. After lesions, two adult monkeys did not show any lesion effect. However, in the other two adolescent monkeys, both the total duration and percentage of the rapid eye movements during REM sleep were decreased moderately. The result suggests that the relation between the FEF and the regulation of the rapid eye movements during REM sleep may be affected by age factor, also indicating that both the functions of the FEF and the mechanisms underlying the control of rapid eye movements during REM sleep might not be the same throughout the whole life span of an animal.

Age Factors↗

PubMed2004

Coagulation in the mesangial area promotes ECM accumulation through factor V expression in MsPGN in rats.

It is well known that tissue factor starts the extrinsic coagulation pathway, which activates factor X to Xa, and factor V is a membrane-bound potent cofactor for the terminating stage of prothrombin activation by factor Xa. In a previous in vitro study, factor V was induced in cultured mesangial cells by inflammatory stimulation and increased expression of factor V promoted fibrin generation on the cultured mesangial cell surface. We report that extracellular matrix (ECM) accumulation is increased in association with coagulation in the mesangial area through factor V expression in mesangioproliferative glomerulonephritis (MsPGN). Wistar rats were intravenously injected with rabbit anti-rat thymocyte serum accompanied with or without simultaneous injection of rabbit anti-factor V antibody. Time course study in immunohistochemistry revealed that factor V expression was prominent on day 3 and fibrin-related antigen (FRA) deposition, then ECM accumulation, followed from day 3 to day 8. Massive fibronectin depositions and transforming growth factor (TGF)-beta expression were also noted in glomeruli from the disease control group, markedly higher than those in the normal group, and these depositions and expressions were significantly decreased in the anti-factor V neutralizing antibody-injected group. Northern blot analysis revealed that factor V mRNA expression was prominent on day 3 and was weak on day 8. Double-labeling experiments revealed the frequent colocalization of alpha-smooth muscle actin with factor V, FRA, and fibronectin in the same mesangial areas of glomeruli. TGF-beta, connective tissue growth factor (CTGF), collagen type IV, and fibronectin mRNA were upregulated in the disease control group, and anti-factor V-neutralizing antibody injection suppressed these mRNA expressions in glomeruli. The present results suggest that ECM components accumulation may progress in accordance with coagulation in the mesangial area through mesangial factor V expression and upregulated expression of TGF-beta and CTGF in MsPGN.

Actins↗

PubMed2004

Role of mesangial Factor V expression in crescent formation in rat experimental mesangioproliferative glomerulonephritis.

It has been suggested that fibrin deposition participates in the development of crescents in active glomerulonephritis (GN). In human IgA nephropathy, which is a common form of mesangioproliferative GN (MsPGN), crescent formation is occasionally observed in active disease, leading to end-stage renal failure. Factor V is a membrane-bound potent cofactor for the conversion of prothrombin to thrombin by Factor Xa. An in vivo study was conducted to clarify the contribution of local fibrin production to crescent formation in MsPGN through mesangial Factor V expression. Wistar rats were injected intravenously with rabbit anti-rat thymocyte serum. Three days after injection, mesangiolysis with intense mesangial Factor V expression was observed and immunoelectron microscopy revealed fibrin localization in mesangiolytic lesions, which had spread into the glomerular basement membrane adjacent to the destroyed mesangium, accompanied by clots in Bowman's space. Marked glomerular fibrin deposition, together with its deposition in Bowman's space and cellular crescent formation, was noted with mesangial proliferation on day 8. Specific bands for Factor V mRNA were also detected from isolated glomeruli. Fibrin deposition and cellular crescent formation were significantly suppressed by treatment with anti-Factor V antibody. These results suggest that local fibrin production, following mesangial Factor V expression, together with mesangiolysis that spreads to the adjacent glomerular basement membrane, plays a role in crescent formation in MsPGN.

Animals↗

PubMed2004

Suppressive effects of Sairei-to on mesangial proliferation in a rat model of glomerulonephritis.

BACKGROUND: Sairei-to (TJ-114) is a Japanese herbal medicine of standardized quality, originating from traditional Chinese medicine. In the present in vivo study, we investigated the suppressive effects of TJ-114, Shosaiko-to (TJ-9), and Saiboku-to (TJ-96) on mesangioproliferative glomerulonephritis (MsPGN) in rats. We evaluated the efficacy of these drugs on proteinuria, mesangial cell proliferation, and superoxide dismutase (SOD) activity. METHODS: MsPGN was induced in Wistar rats by intravenous injection of rabbit anti-rat thymocyte serum (ATS). TJ-114, TJ-9, or TJ-96 (500 mg/kg per day) was orally administered to the rats in drinking water from the day of ATS injection (day 0) to day 8, when rats were killed and kidney specimens were collected. The degree of mesangial cell proliferation was evaluated by immunostaining for proliferating cell nuclear antigen (PCNA) or macrophage antigen (ED-1). SOD activity in the homogenate of the renal cortex was also evaluated. RESULTS: The amount of urinary albumin was significantly decreased only in the TJ-114-treated group compared with the disease control group ( P < 0.05). The number of PCNA- or ED-1-positive cells was significantly decreased in all the treatment groups ( P < 0.05, respectively, compared with the disease control group). SOD activity in the renal cortex homogenate was significantly augmented in all the treatment groups, most markedly in the TJ-96- and TJ-114-treated groups ( P < 0.01, respectively, compared with the disease control group). CONCLUSIONS: These results suggest that TJ-114 suppresses the proliferation of mesangial cells through its antioxidative activity.

Animals↗

PubMed2004

Biosorption of americium-241 by immobilized Rhizopus arrihizus.

Rhizopus arrihizus (R. arrihizus), a fungus, which in previous experiments had shown encouraging ability to remove 241Am from solutions, was immobilized by calcium alginate and other reagents. The various factors affecting 241Am biosorption by the immobilized R. arrihizus were investigated. The results showed that not only can immobilized R. arrihizus adsorb 241Am as efficiently as free R. arrihizus, but that also can be used repeatedly or continuously. The biosorption equilibrium was achieved within 2 h, and more than 94% of 241Am was removed from 241Am solutions of 1.08 MBq/l by immobilized R. arrihizu in the pH range 1-7. Temperature did not affect the adsorption on immobilized R. arrihizus in the range 15-45 degrees C. After repeated adsorption for 8 times, the immobilized R. arrihizus still adsorbed more than 97% of 241Am. At this time, the total adsorption of 241Am was more than 88.6 KBq/g, and had not yet reached saturation. Ninety-five percent of the adsorbed 241Am was desorbed by saturated EDTA solution and 98% by 2 mol/l HNO(3).

Adsorption↗

PubMed2004

Recessive, but not dominant, mutations in peripheral myelin protein 22 gene show unique patterns of aggregation and intracellular trafficking.

A characteristic feature of mouse models of the peripheral neuropathies caused by dominant mutations in peripheral myelin protein 22 (pmp22) is the appearance, in Schwann cells, of pmp22 aggregates. Using a set of dominant and recessive pmp22 mutations that cause human disease of varying degrees of severity, we compared their potential for aggregation and trafficking patterns with those of wild-type pmp22. The potential for aggregation was assessed by determining the size distribution of the various pmp22 mutant proteins under conditions where wild-type pmp22 showed little or no aggregation. All disease-causing dominant mutations showed significant aggregation and failed to traffic to the cell surface. Although the position of the dominant mutation in the pmp22 molecule determined both its potential for aggregation and how far it trafficked in the cell, there was no correlation between aggregation and the severity of the disease. On the other hand, recessive mutations were uniquely distinguished from dominant mutations by both the low potential for aggregation and their trafficking to the cell surface. In the course of these studies, it was also noted that the potential for aggregation and the trafficking of mutant pmp22s is influenced by the nature and/or location of the epitope tag.

Animals↗

PubMed2004

NTZIP antisense plants show reduced chlorophyll levels.

We have isolated and characterized a new photosynthetic tissue-specific gene NTZIP (Nicotiana tabacum leucine zipper) from tobacco (N. tabacum). Its deduced amino acid sequence has two highly conserved regions, leucine zipper and [EX(n)DEXRH](2) motifs, which are related to the gene's biochemical functions. NTZIP was expressed in leaves and stems, but was not detected in roots or flowers, suggesting that its physiological functions might be associated with photosynthesis. Northern blot analysis showed that NTZIP mRNA accumulation was induced by light signals, increased greatly under low temperatures and was repressed by strong light illumination. Furthermore, a number of homologs of NTZIP were isolated from cucumber (Cucumis sativus), rape (Brassica napus), clover (Trifolium repens), willow (Salix babylonica), rosebush (Rusa dovurica), wheat (Triticum aestivum) and spinach (Spinacia oleracea), proving the ubiquitous existence of the NTZIP-like genes in higher plants. Transgenic tobaccos constitutively expressing antisense RNA to NTZIP displayed chlorosis and a lack of ability to turn green even under normal growth conditions. The chlorophyll deficiency was further confirmed by chlorophyll content determination and gas exchange analysis. Based on these observations, we propose that NTZIP may be involved in chlorophyll biosynthesis, and might define a novel family of evolutionarily conserved proteins with its homologs in other plant species.

Amino Acid Sequence↗

PubMed2004

cis-Acting sequences that contribute to the synthesis of relaxed-circular DNA of human hepatitis B virus.

Synthesis of the relaxed-circular (RC) genome of hepadnaviruses is a multistep process that requires template switching during reverse transcription. Studies of duck hepatitis B virus indicated the presence of cis-acting sequences, distinct from the donor and acceptor sequences for the template switches, which contribute to the synthesis of RC DNA. However, knowledge about cis-acting requirements distinct from the donor and acceptor sites for human hepatitis B virus (HBV) was lacking. In this study, we searched for cis-acting sequences for synthesis of HBV RC DNA by analyzing a set of deletion variants that collectively represent most of the HBV genome. Sequences of epsilon, DR1, DR2, 5'r, and 3'r were not analyzed in the study. Results from Southern blotting showed that multiple cis-acting sequences were involved in the synthesis of HBV RC DNA. Analysis of several HBV/woodchuck hepatitis virus chimeras corroborated the findings from the analysis of deletion variants. This study represents a comprehensive and quantitative analysis of cis-acting sequences that contribute to the synthesis of HBV RC DNA.

DNA Replication↗

PubMed2004

[Effect of nandrolone phenylpropionate on hepatic albumin mRNA and granulational alpha 1(I) procollagen mRNA in burned rats].

OBJECTIVE: To assess the mechanism for the effect of nandrolone phenypropionate (NP) on hepatic albumin mRNA and granulational alpha 1(I) procollagen mRNA in burned rats with the aim to underpin the clinical application of anabolic steroids. METHODS: Thirty-two Wistar rats with a deep second-degree cutaneous burn of 20% total body surface area were randomly divided into two groups to receive either 5 mg/kg NP (NP group) or normal saline as placebo(control group) every other day. The expression copy quantities of albumin-mRNA in liver tissue and alpha 1 (I) procollagen mRNA in granulation wound were measured by quantitative fluorescent RT-PCR respectively on the post-burned days 4, 7, 14 and 21. RESULTS: The expression levels of albumin-mRNA and alpha 1 (I) procollagen mRNA in NP group were much higher than those in control group. The 7th and 14th days were the periods in which the albumin-mRNA and alpha 1 (I) procollagen mRNA expression had been increasing obviously (P < 0.01). CONCLUSION: Nandrolone phenylpropionate could effectively up-regulate the expression of albumin-mRNA in liver tissue and the alpha 1 (I) procollagen mRNA in granulation wound.

Albumins↗

PubMed2004

[Posterior lumbar intervertebral fusion device and a new transpedical screw system for treatment of lumbar spondylolisthesis].

OBJECTIVE: To observe the effect of posterior lumbar intervertebral fusion (PLIF) device and a novel transpedical screw system for the treatment of lumbar spondylolisthesis. METHODS: Thirty-three patients with lumbar spondylolisthesis were treated with PLIF device for intervertebral fusion after total laminectomy and internal fixation with the novel transpedical screw system. RESULTS: The patients were followed up for 6 to 36 months with an average of 18.6 months. Nerve injuries and infection of the incisions occurred in none of the cases postoperatively, and no cases exhibited PLIF device displacement or transpedical screw loosening or breaking, nor were other complications seen in this group. The clinical results were excellent in 21 cases, good in 10 cases, and acceptable in 2 cases according to the standard of Brantigan. CONCLUSION: PLIF device and new transpedical screw system constitute good treatment modalities for lumbar spondylolisthesis, with such merits as full decompression of the spinal canal, good restoration of the vertebral body, immediate pain relief and reliable fixation of the vertebral body to allow early force loading postoperatively, and are therefore suitable for treating lumbar spondylolisthesis.

Adult↗

PubMed2004

[Effects of nandrolone phenylpropionate on fibroblasts after injury in rats].

OBJECTIVE: To explore the effects of nandrolone phenylpropionate (NP) on fibroblasts after injury in rats. METHODS: Thirty-two Wistar rats with a deep second-degree scald injury and 20% total body surface area were randomly divided into two groups to receive either 5 mg/kg NP (NP group) or normal saline as placebo (control group) every other day. Integrated optical density (IOD) of androgen receptor (AR) and mRNA expression level of alpha1 (I) procollagen were measured by immunohistochemistry and quantitive fluorescent RT-PCR individually on the post-burn days 4, 7, 14 and 21. Fibroblasts were isolated from granulation tissue of a Wistar rat and were cultured in RPMI1640 with the addition of NP at different concentrations. Cell viability of fibroblasts was measured by MTT test, and the proliferative index, by flow cytometry (FCM). RESULTS: (1) Compared with the A value of the concurrent control group, higher A values were seen in NP groups containing different concentrations of NP, and significant difference of proliferative index was observed in NP group, P<0.05. (2) The expression of alpha1 (I) procollagen mRNA in NP groups was much higher than that in control groups. A significant difference between the two groups was noted on the post-burn days 7, 14 and 21, P<0.05, but no difference was seen on day 4. (3) The density of AR on fibroblasts in NP group was higher than that in control group at each time point. And a positive correlation between the expression of alpha1 (I) procollagen mRNA and the quantity of AR on fibroblasats was confirmed (r = 0.836). CONCLUSION: Nandrolone phenylpropionate could promote fibroblast replication, increase the mRNA level of alpha1 (I) procollagen and enhance the density of AR on fibroblasts.

Anabolic Agents↗

PubMed2004

[Phase separation and transport behaviors in La(0.7 - x)Dy(x)Sr0.3MnO3 system].

The influence of Dy doping (0.00 < or = x < or = 0.30) on magnetic and electric properties of La0.7Sr0.3MnO3 was studied by measuring M-T curves, M-H curves, ESR curves, rho-T curves and MR-T curves of the samples. The experimental results indicate that all samples undergo the transition from paramagnetism to ferromagnetism at T(C). When T < T(C), the doped samples enter the cluster-spin glass state, and the antiferromagnetism is exhibited at lower temperature. For the samples x = 0.2, the phase separation occurs at the temperature far above T(C), the variation in magnetic structure caused by Dy doping leads to colossal magnetoresistance.

English Abstract↗