Biomedical subjects

Qiang He

Publications and source records attributed to Qiang He.

48 records · Page 3Linked to original sources

PubMed2003

[Completely reversed acute rejection episodes do not influence the long-term renal allograft survival].

OBJECTIVE: To assess the influence of times and duration of acute rejection episodes and the effect of antirejection therapy in renal transplantation recipients on the long-term survival of renal allograft. METHODS: The clinical data of 946 patients who received renal transplantation were analyzed to analyze the survival of renal allograts in different conditions: times of rejection episode, time of onset of acute rejection, and effect of antirejection therapy by life table and Wilcoxon test, and to identify the risk factors through Cox regression analysis. RESULTS: During the follow-up with a range of 3 approximately 158 months acute rejection occurred in 172 patients. The 946 cases of kidney transplantation were divided into rejection free group (NAR, n = 774), one time rejection group (1AR, n = 159), and twice and more rejection group (2AR, n = 13) according to the times of rejection. The 1AR group was subdivided into completely reversed group (CAR) and incompletely reversed group (1AR). The 1AR cases were subdivided into early-stage rejection group (EAR, with episode within 90 days after transplantation, n = 112) and late-stage rejection group (LAR, with episode 90 days later transplantation, n = 47) according to the onset time of rejection episode. The five-year survival rate was 70.9% in the AR group (n = 172) and was 93.3% in the NAR group (P < 0.000 1). The ten-year survival rate of renal allografts was 29.8% in the AR group, and was 83.3% in the NAR group (P < 0.000 1). The 5-year survival rate of renal allograft was less than 30% in the 2AR group, significantly lower than those in the NAR and IAR groups (P < 0.000 1 and P< 0.003). The 5-year survival rate of renal allograft was 89.0% in the EAR group, significantly higher than that in the LAR group (48.9%, P < 0.000 1). The 8-year survival rate was 84.3% in the EAR group, significantly higher than that in the LAR group (32.1%, P < 0.000 1). Both the survival rates of renal allograft in the EAR and LAR groups were significantly lower than that in the NAR group (P = 0.025 and P < 0.000 1). The condition had been completely reversed in 95 patients and incompletely reversed in 54 patients, and failed to be improved in 10 patients out of the 159 cases in the IAR group after antirejection therapy. The 5-year survival rate of renal allograft was 93.9% in the CAR group, significantly higher than that in the IAR group (63.1%, P < 0.000 1) but not significantly different from that in the NAR group (P = 0.96). The 8-year survival rate of renal allograft was 89.2% in the CAR group, significantly higher than that in the IAR group (41.4%, P < 0.000 1) but not significantly different from that in the NAR group (P = 0.96). The time of rejection onset was not the main factor effecting survival rate of grafts. The main risk factor influencing the long-term survival of renal allograft was the therapeutic effect after the onset of rejection with a risk rate of 3.14. CONCLUSION: The acutely rejected renal allografts have poor long-term survival. The long-term survival rate of renal allograts with acute rejection that occurs only once and is completely recovered after antirejection therapy is not significantly different from that of the renal allografts in NAR group.

Acute Disease↗

PubMed2003

Dynamic and morphological investigation of phospholipid monolayer hydrolysis by phospholipase C.

The hydrolytic reaction of L-alpha-dipalmitoylphosphatidylcholine (L-DPPC) monolayer catalyzed by phospholipase C (PLC) has been investigated using monomolecular membrane technique and Brewster angle microscopy (BAM) at the air/water interface. The curves of surface pressure as a function of time determined a lag-burst process of L-DPPC monolayer hydrolysis by PLC. The BAM images recorded the changes of domains formed in the coexistence region of liquid-condensed (LC) and liquid-expanded (LE) phases during the monolayer hydrolysis. The changes of domain shape and size and the increase of domain number reflect the decrease of reactant and molecular rearrangement process of the main hydrolysis product, dipalmitoylglycerol (DPG). A new phase was observed after the hydrolysis reaction was completed.

1,2-Dipalmitoylphosphatidylcholine↗

PubMed2003

Characterization of Fe(III) reduction by chlororespiring Anaeromyxobacter dehalogenans.

Anaeromyxobacter dehalogenans strain 2CP-C has been shown to grow by coupling the oxidation of acetate to the reduction of ortho-substituted halophenols, oxygen, nitrate, nitrite, or fumarate. In this study, strain 2CP-C was also found to grow by coupling Fe(III) reduction to the oxidation of acetate, making it one of the few isolates capable of growth by both metal reduction and chlororespiration. Doubling times for growth of 9.2 and 10.2 h were determined for Fe(III) and 2-chlorophenol reduction, respectively. These were determined by using the rate of [(14)C]acetate uptake into biomass. Fe(III) compounds used by strain 2CP-C include ferric citrate, ferric pyrophosphate, and amorphous ferric oxyhydroxide. The addition of the humic acid analog anthraquinone 2,6-disulfonate (AQDS) increased the reduction rate of amorphous ferric iron oxide, suggesting AQDS was used as an electron shuttle by strain 2CP-C. The addition of chloramphenicol to fumarate-grown cells did not inhibit Fe(III) reduction, indicating that the latter activity is constitutive. In contrast, the addition of chloramphenicol inhibited dechlorination activity, indicating that chlororespiration is inducible. The presence of insoluble Fe(III) oxyhydroxide did not significantly affect dechlorination, whereas the presence of soluble ferric pyrophosphate inhibited dechlorination. With its ability to respire chlorinated organic compounds and metals such as Fe(III), strain 2CP-C is a promising model organism for the study of the interaction of these potentially competing processes in contaminated environments.

Acetic Acid↗

PubMed2003

Expression of p27, cyclin E and cyclin A in hepatocellular carcinoma and its clinical significance.

AIM: To investigate the expression of p27, cyclin E and cyclin A in hepatocellular carcinoma (HCC) and its potential clinical significance. METHODS: Expression of p27, cyclin E and cyclin A in 45 HCC specimens and 30 adjacent noncancerous lesions obtained from 45 patients during surgery was examined by immunohistochemical SABC assay. The diameter of tumor ranged from 1 cm to 19 cm (d< or =5 cm, 9 samples; 5 cm 10 cm, 17 samples). The tumors were graded according to the criteria described by Edmondson-Steiner: well-differentiated HCC group (Grade I+II), 26 samples; poorly-differentiated HCC group (Grade III+IV), 19 samples. According to the clinical-pathologic features, 19 samples were poorly encapsulated, 15 samples had portal invasion of cancer, 11 samples had extrahepatic metastasis, and 12 samples had intrahepatic metastasis. All of the samples were classified as the invasive and metastatic group, while the remaining was classified as the non-invasive and non- metastatic group. RESULTS: The average labeling index (LI) of p27 in HCC lesions was significantly higher than that in adjacent noncancerous lesions (45.87+/-14.21 vs 33.77+/-12.92, t=3.745, P<0.001). The LI of p27 was associated with differentiation, invasiveness and metastasis of the tumors (34.46+/-12.29 vs 52.80+/-11.36, t=5.17; 41.42+/-12.86 vs 51.44+/-14.10, t=2.48; P<0.05). Cyclin E was overexpressed in 16 cases (35.6%) while cyclin A was overexpressed in 21 cases (46.7%) in HCC lesions. No overexpression of cyclin E or cyclin A could be observed in adjacent non-carcinoma lesions and normal liver tissues. The overexpressions of cyclin E and cyclin A were correlated with differentiation, tumor thrombus, invasiveness and metastasis (P<0.05). Expression of cyclin E was significantly correlated with expression of cyclin A (r=0.329, P<0.05). The LI of p27 was significantly decreased in cyclin E, cyclin A positive groups (40.33+/-11.91 vs 49.50+/-13.76, t=3.05; 38.86+/-11.19 vs 52.57+/-12.62, t=3.89; P<0.05). CONCLUSION: p27, cyclin E, cyclin A play cooperative roles in HCC tumorigenesis, differentiation, invasiveness and metastasis. Detection of their expression may be helpful in prediction of tumor progression.

Adult↗

PubMed2003

Impact of acute rejection episodes on long-term renal allograft survival.

OBJECTIVE: To assess the impact of the number, and time of acute rejection (AR) and outcome of anti-rejection therapy on the long-term survival of renal allografts and the relative risk factors. METHODS: The Kaplan-Meier analysis and log-rank test were used to calculate the survival rates of patients and grafts in no acute rejection group (NAR, 895 patients), 1 rejection episode group (1AR, 183), 2 and more than 2 rejection episodes group (2AR, 17), acute rejection group [AR (1AR + 2AR), 200], early acute rejection group (within 90 days after transplantation, EAR, 125), late acute rejection group (91 days later, LAR, 58), completely AR reversed group (CAR, 105), and incompletely AR reversed group (IAR, 68). The relative risk factors were analyzed by the Cox proportional hazards regression. RESULTS: The 5- and 10-year survival rates of renal allografts were 75.4% and 17.1% in AR and 93.2% and 86.5% in the NAR group (P < 0.0001). The long-term graft survival was much lower in the 2AR group than in the NAR or 1AR groups (P < 0.0001 and P = 0.002, respectively). It was similar in either the NAR or CAR groups (P = 0.31), but it was significantly lower (P < 0.0001) in the IAR group. Multivariate Cox regression analysis revealed that the outcome of anti-rejection therapy is an important risk factor affecting the long-term survival of allografts. CONCLUSIONS: AR is significantly associated with poor long-term survival of renal allografts. But the long-term graft survival of patients with one acute rejection but completely reversed is not significantly different from that of patients without acute rejection.

Adolescent↗

PubMed2002

Induction characteristics of reductive dehalogenation in the ortho-halophenol-respiring bacterium, Anaeromyxobacter dehalogenans.

Anaeromyxobacter dehalogenans strain 2CP-C dehalogenates ortho-substituted di- and mono-halogenated phenols and couples this activity to growth. Reductive dehalogenation activity has been reported to be inducible, however, this process has not been studied extensively. In this study, the induction of reductive dehalogenation activity by strain 2CP-C is characterized. Constitutive 2-chlorophenol dechlorination activity occurs in non-induced fumarate-grown cells, with rates averaging 0.138 micromol of Cl- h(-1) mg of protein(-1). Once induced, these cultures dechlorinate 2- chlorophenol (2-CP) at rates as high as 116 micromol of Cl(-1) h(-1) mg of protein(-1). Dechlorination of 2-CP is induced by phenol, 2-chlorophenol, 2,4-dichlorophenol, 2,5-dichlorophenol, 2,6-dichlorophenol, and 2-bromophenol. Of the substrates tested, 2-bromophenol shows the highest induction potential, yielding double the 2-chlorophenol dechlorination rate when compared to other inducing substrates. No induced dechlorination is observed at concentrations less than 5 microM 2-CP. When fumarate cultures were diluted 100-fold, fumarate reduction rates were reduced roughly according to the dilution factor, while dechlorination rates were similar in fumarate grown cells amended with 2-CP and cells diluted 100-fold prior to the addition of chlorophenol. This indicates that the majority of the fumarate-grown cells in late log phase were not induced when exposed to inducing substrates such as 2-CP. This observation may have ramifications on the success of bioaugmentation using halorespiring bacteria, which traditionally relies on growing cultures using more readily utilized substrates. The rapid dechlorination rate and unique induction pattern also make strain 2CP-C a promising model organism for understanding the regulation of reductive dehalogenation at the enzymatic level.

Biodegradation, Environmental↗

PubMed2002

Autologous fixed tumor vaccine: a formulation with cytokine-microparticles for protective immunity against recurrence of human hepatocellular carcinoma.

We developed a tumor vaccine consisting of fixed hepatocellular carcinoma (HCC) cells/tissue fragments, biodegradable microparticles encapsulating granulocyte-macrophage-colony stimulating factor and interleukin-2, and an adjuvant. The vaccine protected 33% of syngeneic mice from HCC cell challenge. The vaccine containing human autologous HCC fragments showed essentially no adverse effect in a phase I/IIa clinical trial and 8/12 patients developed a delayed-type hypersensitivity (DTH) response against the fragments. Although 2 of 4 DTH-response-negative patients had recurrence after curative resection, the DTH-response-positive patients had no recurrence. The time before the first recurrence in the vaccinated patients was significantly longer than that in 24 historical control patients operated in the same department (P < 0.05). This formulation is a promising candidate to prevent recurrence of human HCC.

Animals↗

PubMed2002

Real-time quantitative PCR for detection of Helicobacter pylori.

Helicobacter pylori is one of the most common chronic infections in humans, in whom it is a key etiological factor in peptic ulcer disease, gastric mucosa-associated lymphoid tissue lymphoma, and gastric adenocarcinoma. Humans are the bacterium's only host. Here we report the development of a real-time quantitative (Q) PCR-based assay to measure ureC gene copy number to detect H. pylori, based on the fact that there is only one copy of the ureC gene per bacterium. Upon optimization of LightCycler Q-PCR conditions, we obtained a standard curve with a linear range (correlation coefficient = 1) across six logs of DNA concentration. We were able to accurately quantify as few as 1,000 bacteria in our assay. Analysis of variance on 15 randomly selected clinical samples showed good reproducibility of this assay. Comparison of Q-PCR results with bacterial culture and histopathological results from an additional 85 clinical biopsy samples showed a significant difference for the presence of H. pylori. Many samples that were negative for H. pylori by culture and histopathology were positive by Q-PCR. Contamination of PCR by H. pylori or H. pylori genetic material could not be ruled out. In summary, we developed a rapid, sensitive, and real-time Q-PCR method for detecting H. pylori. This technique offers a significant improvement over other available methods for detecting H. pylori in clinical and research samples.

Computer Systems↗

PubMed2002

PELA microspheres loaded H. pylori lysates and their mucosal immune response.

AIM: To prepare poly (D,L-lactide)-polyethylene glycol copolymer (PELA) microspheres loaded H.pylori lysates or Cystografin and observe their targeting in gastrointestinal mucous membrane or analyze the mucosal immune responses by oral administration. METHODS: PELA microspheres loaded H.pylori lysates or Cystografin were prepared by double emulsion evaporation method. Their distribution in gastrointestinal mucous membrane was observed by CT. Balb/c mice orally immunized in mucosal immune responses, whose antibody production in salivary and gut washing and antibody secreting cells in Peyer's patches (PP) were estimated by ELISA and ELISPOT, respectively. The microspheres physical properties, such as particle size, protein level and morphology were investigated. RESULTS: All prepared microspheres were found to have a smooth surface morphology from 3.20-4.05 microm in diameter and high encapsulation efficiency from 74.9-82.2 %. No significant correlation in their physical properties was shown, depending on their molecular weight at the similar composition ratio. Immunization with all types of PELA-Hp microspheres elevated the saliva sIgA level at week 3 by approximately 3-4 times that with soluble antigen, which was greatly enhanced after boosting. At one week after last immunization with all types of PELA-Hp microspheres (week 8), the specific sIgA-ASCs, IgG-ASCs and sIgA in salivary rose obviously. In intestinal Peyer's patches, the specific sIgA-ASCs were 5.92-6.98X10(4)/ml cell and IgG-ASCs were 3.47-4.02X10(4)/ml cell, about 5-9 times higher than those with soluble antigen (P<0.01). ASCs in intestine were more than those in stomach and the majority of the ASCs were sIgA-ASCs. The sIgA in gut washing fluid was 1.62-1.85 OD, about 3-6 times tthat of those with soluble antigen. There were significant differences of the ASCs and sIgA in gut washing fluid as compared with those of PBS and MS-0 (P<0.05). There appeared to be good correlation between sIgA level in gut washing fluid and sIgA-ASCs in intestinal Peyer's patches. CONCLUSION: PELA microspheres may be used as vehicle to delivery antigen and adjuvant in designing oral vaccination.

Administration, Oral↗

PubMedDate not supplied

Lipid peroxidation in IgA nephropathy and the effect of lipo-prostaglandin E1.

BACKGROUND: Lipid peroxidation (LPO) plays a role in glomerulonephritis pathogenesis. The role of LPO in IgA nephropathy (IgAN) and the effect of prostaglandin E1 on it, is not determined. METHODS: Levels of malondialdehyde (MDA), superoxide dismutase (SOD) and vitamin E (vitE) were measured in 42 patients with IgAN and in 31 healthy controls. Clinical nephropathy parameters such as daily proteinuria (DP), serum creatinine (Cr) and Cr clearance were obtained. Forty-two IgAN patients were divided into two subgroups according to renal pathology severity. Twenty-one patients with IgAN received lipo-prostaglandin E1 (PGE1) treatment and the other 21 patients received saline as a control. RESULTS: The serum activity of SOD and vitE in IgAN patients was significantly lower than in healthy controls, while the MDA level was higher in the patient groups. DP-related positively to MDA, while it related negatively to SOD and vitE. Cr clearance related negatively to MDA, while it related positively to SOD and vitE. In the moderate pathological group, the MDA level was significantly higher and the SOD activity was lower than in the mild pathological group. The MDA level in the PGE1 treated group was lower than in the control group, but the activity of SOD and vitE did not differ significantly from the control group. DP declined and Cr clearance increased in the PGE1 treated group, while no significant change in serum Cr was noted. CONCLUSIONS: LPO in IgAN was evident and was at least attributed to the decline in antioxidant ability. LPO could play a role in IgAN pathogenesis, and PGE1 is able to ameliorate the LPO in IgAN patients.

Adult↗

PubMedDate not supplied

Autologous tumor vaccine lowering postsurgical recurrent rate of hepatocellular carcinoma.

BACKGROUND/AIMS: A tumor vaccine consisting of formalin-fixed hepatocellular carcinoma (HCC) tissue fragments, biodegradable sustained-releasers of granulocyte-macrophage-colony stimulating factor (GM-CSF) and interleukin-2 (IL-2), and an adjuvant was developed. The aim of this study was to evaluate the effects of autologous tumor vaccine for protective immunity against HCC. METHODOLOGY: C57BL/6J mice were immunized intradermally with the Hepa1-6 tumor vaccine on day 0 and 7, followed by intrahepatic challenge with live Hepa1-6 cells. On day 21, the tumor volumes were measured and the effect of tumor vaccine was evaluated. Lymphocytes from the immunized mice were cultured and the specific cytotoxicity against Hepa1-6 was accessed. Then from March 1999 to June 2003, 67 patients with HCC undergoing curative resection were randomly divided into a tumor vaccine group (n = 32) and a control group (n = 35). Patients in the tumor vaccine group received 3 vaccinations at a 2-week interval and the control group only adjuvant treatment for symptoms. A delayed-type-hypersensitivity test was performed before and after vaccination. Primary endpoint was time to first recurrence and recurrent rates were analyzed. RESULTS: The tumor vaccine protected 87% of syngeneic mice from Hepa1-6 cells inoculation. In an in vitro experiment, splenocytes from the vaccinated mice exhibited a 56% lytic activity against the Hepa1-6 cells at an effector/target (E/T) ratio of 5, whereas they did not exhibit such activity against other tumor cells. The cytotoxic activity was inhibited by the treatment with anti-CD3, anti-CD8, and anti-MHC-class II monoclonal antibodies but not with anti-CD4 and anti-MHC-class I antibodies. In clinical trial, thirty-two patients had completed the tumor vaccine procedure and no essential adverse effect occurred. The follow-up averaged 33.6 months (range from 15 to 54 months). The recurrent rate was significantly better in the tumor vaccine group (1 year, 12.6%; 2 years, 35.9%; 3 years, 54%) than in the control group (1 year, 31.6%; 2 years, 61.3%; 3 years, 72.1%; P = 0.037). 23/32 patients developed a DTH response against the fragments of HCC and DTH-response-positive patients had a lower recurrent rate than DTH-response-negative patients (7/23 vs. 5/9). CONCLUSIONS: The autologous tumor vaccine is a promising adjunctive modality to prevent recurrence of human HCC.

Adolescent↗

PubMedDate not supplied

Surgical treatment for hepatocellular carcinoma with portal vein tumor thrombus.

BACKGROUND/AIMS: To study the value of surgical treatment for hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). METHODOLOGY: From January 1997 to December 2001, 63 cases of HCC with portal vein tumor thrombus underwent liver resection combined with PVTT removal (group 1). Between December 2001 and December 2003, 20 patients received adjuvant portal vein chemotherapy (PVC) after the surgical procedures mentioned above (group 2). Treatment outcome and the surgical features in these two groups were studied. RESULTS: The median overall survival in group 2 was significantly longer than that in group 1 (10.9 months vs. 7.8 months, p < 0.05). There were significant differences between the survival of the two groups (log-rank, p < 0.05). In group 1 the 1-, 3-, and 5-year survival rates were 18.0%, 14.8% and 1.6%, respectively. In group 2 the 1-year survival rate was 30%. CONCLUSIONS: Liver resection combined with PVTT removal and the postoperative PVC is beneficial to the survival of HCC patients with PVTT. Postoperative PVC might enhance the effect of these surgical approaches.

Antibiotics, Antineoplastic↗