PubMed Health⌕ Search

Biomedical subjects

Jing Liu

Publications and source records attributed to Jing Liu.

At least 307 records · Page 17Linked to original sources
PubMed2003

Production of soluble and functional engineered antibodies in Escherichia coli improved by FkpA.

Overproduction of genetically engineered antibodies, such as single-chain antibodies (scAbs) in Escherichia coli often results in insoluble and inactive products known as inclusion bodies. We now report that fusion or co-expression of FkpA, the E. coli periplasmic peptidyl-prolyl-isomerase with chaperone activity, substantially improves soluble and functional expression of scAbs. Anti-human bladder carcinoma scAb (PG) and anti-human CD3 x anti-human ovarian carcinoma-bispecific scAb (BH1) were fused with FkpA on the pTMF-based plasmid and expressed in E. coli. More than half of the amount of each expressed fusion protein FkpA-PG or FkpA-BH1 was soluble. In addition, the fusion protein cellulose-binding domain from Cellulomonas fimi (CBD)-PG and anti-human CD3 x anti-human CD28 x anti-human ovarian carcinoma-trispecific scAb (TRI) fused to the pelB (a signal peptide from pectate lysase B of a Bacillus sp.) signal sequence were co-expressed with FkpA under the control of the T7 promoter. A substantial portion of the co-expressed CBD-PG or TRI was soluble. Furthermore, PG, BH1, and TRI were biologically active as judged by ELISA and in vitro cytotoxicity assay. These results suggest that overexpression of FkpA should be useful in expressing heterologous proteins in E. coli.

Antibodies↗
PubMed2003

Expression of hepatitis C virus hypervariable region 1 and its clinical significance.

AIM: To explore the properties of hypervariable region 1 (HVR1) in the envelope 2 gene of hepatitis C virus by analyzing the reactivity of HVR1 fusion proteins from different Chinese HCV strains with sera of patients with chronic hepatitis C and by comparing their reactivity between interferon therapy responders and non-responders. METHODS: Gene fragments of HVR1 of four HCV strains (three genotype 1b and one genotype 2a) were amplified from pGEMT-E2 plasmids and sub-cloned into pQE40 vectors respectively to construct recombinant expression plasmids which expressed HVR1 fused downstream to DHFR in Escherichia coli strain TG1. The purified DHFR- HVR1 proteins were then used to detect the anti-HVR1 antibodies in 70 serum samples of patients with chronic hepatitis C. RESULTS: Four DHFR- HVR1 fusion proteins were successfully expressed in E.coli (320-800 ug fusion proteins per 100 ml culture). Each fusion protein (SH1b, BJ1b, SD1b and SD2a) reacted with 72.8 % (51/70), 60 % (42/70), 48.6 % (34/70), and 58.6 % (41/30) of the anti-HCV positive patients' sera respectively by ELISA. 57 % (4/7) of non responders reacted with all four HVR1 fusion proteins, while only 15.3 % (2/13) of responders reacted with all of them. The O.D. values of sera from IFN therapy responders were significantly higher than those of non responders (P<0.05). CONCLUSION: The selected HVR1 fusion proteins expressed in E. coli can broadly react with HCV-infected patients' sera. The intensity and/or quality of the immune response against HCV may be a critical factor determining the response to interferon treatment. With the evolution of virus strains, anti-HVR1 antibodies can not neutralize all the quasispecies. A polyvalent and high immunogenic vaccine comprising a mixture of several HVR1 sequences that cover the reactivity of most HCV isolates may be useful.

Adult↗
PubMed2003

[Measurement of the reactive oxygen species and cytokines in the seminal plasma of leukocytospermic patients].

OBJECTIVES: To detect the levels of reactive oxygen species (ROS), superoxide dismutase(SOD) and interleukin 8(IL-8) in seminal plasma of infertile patients, and evaluate the possible relationship between those levels. METHODS: Semen was collected from normal donors (15 cases), infertile men without infection (16 cases), and infertile men with infection (leukocytospermia, 11 cases). The routine analysis of semen was accomplished, and then the levels of IL-8, malondialdehyde (MDA), SOD, and white blood cell (WBC) were examined. The correlative analysis between the level of ROS and other parameters in these populations was made. RESULTS: In leukocytospermic group, the levels of MDA, WBC, and IL-8 were higher than those in the other two groups (P < 0.001). Significantly positive correlation was observed between IL-8 and MDA (r = 0.852, P < 0.001) and between the levels of IL-8 and WBC. CONCLUSIONS: These findings suggest that increased oxidative stress in patients with leukocytospermia may cause the increase of IL-8(r = 0.818, P < 0.01). The increased oxidative stress may be due to defect in ROS scavenging system.

Adult↗
PubMed2003

[The trends of body mass index and overweight in population aged 25 - 64 in Beijing during 1984 - 1999].

OBJECTIVE: To analyse the trends of body mass index (BMI) and overweight in a population aged 25 through 64 years in Beijing. METHOD: During 1984 to 1999, five cross-sectional surveys on cardiovascular disease (CVD) risk factors were carried out in the CVD monitoring population in Beijing. The mean levels and trends of BMI as well overweight in different sexs, age groups and areas were analysed. RESULTS: (1) In the period of 1984 to 1999, the mean BMI increased from 23.3 to 24.0 (kg/m(2)) in population aged 25 to 64 years, and overweight increased from 27.5% to 35.9%. (2) From 1984 to 1999, the prevalence of overweight increased from 23.5% to 43.3% in males. This increasing trend was seen in both urban and rural populations and in all age groups. Prevalence of overweight decreased from 36.0% to 23.3% in urban females, but increased from 28.4% to 46.0% in rural females. (3) From 1984 to 1999, prevalence of overweight increased from 29.1% to 31.8% in urban population, while 22.1% to 49.6% in rural population. BMI and prevalence of overweight were higher in urban than in rural (P < 0.05) in 1984 to 1985 but the levels in rural were approaching and exceeding the levels in urban (P < 0.05) in 1999. CONCLUSION: Trends of BMI and overweight increased in the urban males and both males and females in the rural, while the increase of both BMI and overweight was seen more rapid in rural than in urban.

Adult↗
PubMed2003

[Study on the distribution and association of cholesteryl ester transfer protein-TaqIB polymorphism and plasma concentration in general population].

OBJECTIVE: To study the distribution of cholesteryl ester transfer protein (CETP)-TaqIB polymorphism and plasma concentration in general population and the association between the two. METHODS: A cross-sectional study was carried out in a general population of Beijing in 1999, using stratified-random sampling method. CETP-TaqIB polymorphism and plasma CETP concentration were determined in 719 individual aged 45 - 64 years. RESULTS: (1) Frequencies of B1B1, B1B2 and B2B2 genotypes were 0.356, 0.478 and 0.166, respectively. The frequency of allele B2 was 0.405. Distributions of genotypes and alleles were homogeneous in both sexes. (2) Plasma CETP concentration manifested as a normal distribution, with the mean of 2.03 micro g/ml. The value of female was 20.3%, higher than that of male (P < 0.001). There were no differences among age groups. (3) Plasma CETP concentrations of B1B1 and B1B2 were 19.6% and 13.4% higher than that of B2B2 homozygotes. (4) Stratified by lipid levels, smoking and alcohol consumption, only when tryglyceride exceeded 150 mg/dl, with no significant difference among three genotypes. The effect of lipids, smoking and alcohol consumption status was more significant in B1B2 heterozygotes. CONCLUSION: CETP-TaqIB polymorphism was a determinant of plasma CETP concentration. However, the effect could be modified by other factors, such as lipids, smoking and alcohol consumption.

Carrier Proteins↗
PubMed2003

[Effects of infrasound on visual electrophysiology in mice].

OBJECTIVE: To investigate the possible effects of infrasound on visual functions. METHOD: One hundred and fifty mature male Kunming-mice were divided into 5 groups, in which one was control and the other four were exposed to infrasound of 8 Hz, 90 dB; 8 Hz, 130 dB; 16 Hz, 90 dB and 16 Hz, 130 dB 2 h/d respectively. The exposure time for them were 0, 1, 4, 7, 14 and 21 d respectively, each group was divided into 6 sub-groups. Electroretinogram (ERG), oscillatory potentials (OPs), and visual evoked potential (VEP) were recorded after exposure. RESULT: The visual electrophysiological indices after 8 Hz, 90 dB and 16 Hz, 90 dB exposures were similar except for a little difference at some temporal points (P<0.05). Most of the indices in 8 Hz, 130 dB group changed after 7 d exposure, and the longer the exposure, the more obvious changes were observed (P<0.01). The indices in 16 Hz, 130 dB group changed obviously after 1 d and reversed with increase of exposure time (P<0.01). CONCLUSION: The effect of infrasound on visual functions are related to its frequency and intensity. Infrasound of different frequencies causes different levels of retinal resonance, which leads to different degrees of cellular lesion and produces different electrical potentials.

Acoustic Stimulation↗
PubMed2003

[An experimental study of the intracellular distribution and the activation of mitogen-activated protein kinases in myocardial cells in scalded rats].

OBJECTIVE: To investigate the intracellular distribution and the activation of mitogen-activated protein kinases (MAPKs) in myocardial cells in scalded rats. METHODS: Wistar rats were used in this study and forty of them were inflicted with 40% III degree scald on the back and eight normal ones as control. The samples of plasma and myocardial tissue were harvested at 1, 3, 6, 12 and 24 postburn hours (PBHs), and samples were also obtained from normal rats as control. The plasma CK-MB activity was determined by routine method. The activation states of all the members of MAPKs [p38 kinase, ERKs (extracellular signal-regulated protein kinases) and JNK (c-Jun N-terminal kinase)] in the myocardial tissue samples were detected by Western blotting. The tissue slides were stained by immunohistochemistry methods. RESULTS: Activation of p38 kinase and ERK with nuclear translocation was found postburn, especially during 1, 3 and 6 PBHs (P < 0.01). But there was no activation of JNK during 1 - 24 PBHs. The plasma CK-MB content increased at 3 PBH and reached summit at 12 PBHs (P < 0.05 - 0.01). CONCLUSION: p38 kinase and ERK signal pathways might play important roles in the early postburn injury of myocardial cells, inducing myocardial injury.

Animals↗
PubMed2003

[Detection of anti-HCV in blood recipients with hematonosis].

OBJECTIVE: To observe hepatitis C virus (HCV) infection in blood recipients with hematonosis, and to investigate the significance of anti-HCV detection in the patients. METHODS: Anti-HCV was detected by enzyme-linked immunosorbent assay (ELISA) in 176 hematonosis patients before blood transfusion, the result of anti-HCV was compared with control (417 cases), and 95 blood recipients were followed up for 6-12 months after the transfusion. RESULTS: The positive rate of anti-HCV was 5.68% (10/176) in hematonosis patients before transfusion, higher than both in the control [0.72% (3/417), P < 0.01] and in the patients with general surgery [2.23% (21/942), P < 0.05], and no new infection case was found after the transfusion. CONCLUSION: HCV infectionin in blood recipients with hematonosis should be paid attention to, and the detection of anti-HCV is necessary for patients before blood transfusion.

Anemia, Aplastic↗
PubMed2003

[Clinical study on hematopoietic reconstitution in patients with leukemia by haploidentical bone marrow transplantation].

To investigate the properties of haploidentical donor-derived bone marrow engraftment and hematopoietic reconstitution in patients received bone marrow transplantation, 15 patients with leukemia received bone marrow grafts without T cell depletion from their family donors of those with 2-3 mismatched loci of HLA antigens. The donors were given G-CSF 250 micro g/day for 7 days prior to marrow harvest. All patients were treated with conditioning regimens consisting of high-dose of Ara-C, cyclophosphamide, and total body irradiation. A four-agent based GVHD prophylaxis was used as cyclosporine A, MTX, ATG and mycophenolate mofetile (MMF). Donor engraftment was evaluated as identification of HLA locus, chromosome karyotype, DNA fingerprinting, blood type and other parameters such as occurrence of GVHD, recovery of peripheral blood cell counts as well as normal myelogram. The results showed that successful and stable engraftment was established in all patients. The median time of granulocyte counts > 0.5 x 10(9)/L and platelet > 20 x 10(9)/L was 18 (13-23) and 22 (16-32) days, respectively. One of the patients relapsed despite the bone marrow chimerism appearing after transplantation. The grade I acute GVHD occurred in 8 and grade II-IV in 5 of the 15 patients. Of the patients, 7 received marrow grafts from donors of opposite sex were identified for donor engraftment by chromosome analysis, 4 by blood typing, 7 with HLA locus analysis and 1 with DNA fingerprinting. In conclusion, HLA haploidentical bone marrow transplantation is feasible with a series of management including mobilization with G-CSF in donors, intensive conditioning and proper immunosuppressants, which enable the allo-transplants to stride across the immunological barrier.

Adolescent↗
PubMed2003

[A study on the incidence of cardiovascular disease on the metabolic syndrome in 11 provinces in China].

OBJECTIVE: To explore the association of metabolic syndrome with CVD in a cohort study involving 11 provinces. METHODS: A cohort study was carried out in a population of 27 739 subjects (age 35 - 64 years). A baseline survey on the risk factor of cardiovascular disease was done in 1992. Incidence rate and relative risk were calculated for metabolic syndromes. RESULTS: (1) The age-standardized incidence rate of cardiovascular disease for metabolic syndromes (MS) was higher than those without (MS) in this cohort (MS 652.3/100,000, not MS 206.7/100,000, RR = 3.12, P < 0.001). (2) The incidence rate of cardiovascular disease for patients with hypertension but low HDL cholesterol and high waist was the highest (910.2/100,000 in man, 930.7/100,000 in woman) among all metabolic syndromes patients. (3) The predictive risk factors for cardiovascular disease were age, cigarette smoking, BMI, total cholesterol and metabolic syndrome in men, with age, BMI and metabolic syndrome in women. CONCLUSION: The incidence rate of cardiovascular disease on the metabolic syndrome was high in 11 provinces in China. Age, BMI and metabolic syndrome were the predictive risk factors of cardiovascular disease (especially of cerebrovascular disease). It is essential to prevent risk factors of cardiovascular disease in primary and secondary prevention programs in general population.

Adult↗
PubMed2003

[An efficient approach to the synthesis of a high-quality random peptide repertoire].

During the construction of a random peptide repertoire using degenerate models, unexpected amino acids or stop codons are almost unavoidable. To conquer this shortcoming, a new split-mix-split method of oligonucleotide synthesis was developed. A 13-amino acids random peptide library had been constructed by using this method. The sequencing results of 16 clones indicated that neither stop codon nor codon for cysteine appeared as designed. The occurrence rations of 19 amino acids were also calculated and no obvious amino acid bias had been observed. By using this method, the type and quantity of amino acid at certain position of a peptide could be controlled well, so this split-mix-split method, combined with degenerate could meet the needs of a high diversity random peptide library.

Amino Acid Sequence↗
PubMed2003

[Maximal androgen blockade and maximal androgen blockade combined with 125I brachytherapy for prostatic cancer].

OBJECTIVE: To assess the effect of the maximal androgen blockade(MAB) and MAB combined with 125I brachytherapy on prostatic cancer. METHODS: Forty-four patients with prostatic cancer (from 1993 to 2002), 28 at pathologic stage C and 16 at stage D, were analyzed retrospectively. Thirty-five of them were treated by bilateral orchidectomy and anti-androgen drugs, i.e. MAB, and 9 treated by MAB combined with 125I brachytherapy. The survival rates and the variation of serum prostate-specific antigen (PSA) levels between pre- and post-treatment were compared. RESULTS: The level of PSA decreased from 60.3 micrograms/L to 12.1 micrograms/L in 35 patients treated by MAB, and from 72.1 micrograms/L to 3.6 micrograms/L in 9 patients treated by MAB combined with 125I brachytherapy after 6 months. The post-treatment survival rates were 81.3% (26/32, excluding 3 deaths by other diseases) for patients treated by MAB after a mean follow-up of 39.2 (9-84) months and 100% for patients by MAB combined with 125I brachytherapy after a mean follow-up of 13(7-24) months. CONCLUSION: MAB and MAB combined with 125I brachytherapy are effective for patients with prostatic cancer.

Aged↗
PubMed2003

[Clinical study of a new protocol for acute graft-versus host disease prophylaxis in HLA-haploidentical bone marrow transplantation (BMT)].

OBJECTIVE: To explore the feasibility of a new protocol for acute graft versus host disease (aGVHD) prophylaxis in haploidentical bone marrow transplantation. METHODS: Thirty-eight high-risk leukemia patients underwent haploidentical G-CSF primed bone marrow transplantation without ex-vivo T cell depletion, the donors were given G-CSF 250 microg/d for 7 days prior to marrow harvest. All patients received a same chemo-radiation conditioning regimen, including cytarabin, cyclophosphamide and total body irradiation (TBI). GVHD prophylaxis regimen consisted of ATG, CsA, MTX, Mycophenolate mofetil (MMF) and anti-CD(25) monoclonal antibody (MoAb). RESULTS: All patients achieved engraftment of a median of 19 and 22 days for neutrophil and platelet, respectively. Cytogenetic analysis showed 100% donor hematopoietic cells in all recipients after transplantation. One of the twenty patients (5%) experienced grades II - IV acute GVHD. The recovery of CD(3)(+)CD(8)(+) T cells, CD(19)(+) cells and CD(56)(+) cells after transplantation was within 3 approximately 12 months. Of the 20 patients, 16 were alive with minimal and limited chronic GVHD and karnofsky score over 90% in a median follow-up of 9 months. Disease free survival (DFS) rates was (80 +/- 9)%. CONCLUSION: G-CSF priming marrow graft along with sequential immunosuppressants, especially the addition of anti-CD(25) MoAb for aGVHD prophylaxis could achieve excellent engraftment, proper immune reconstitution and very low incidence of grade II - IV GVHD. The new protocol is effective and feasible in preventing severe acute GVHD and improving DFS.

Adolescent↗
PubMed2003

[Immunological effects of simultaneous injection of dexamethasone-induced apoptotic donor spleen cells in rats with liver transplantation].

OBJECTIVE: To study the immunological effects of simultaneous injection of apoptotic donor spleen cells induced by dexamethasone in rats with liver allotransplantation. METHODS: Four groups of rats were used in this study, each consisting of 10 SD rats and 10 Wistar rats with the former as the recipients and the latter as the donors for liver transplantation. In one of the groups, the recipient rats also received infusion of apoptotic spleen cells (5x10(7)) of the donors induced by an intraperitoneal injection of dexamethasone (at a daily dose of 3 mg/kg) for 3 days before liver transplantation, while in another, the recipient received untreated donor spleen cells. In the third group, the donor was treated with dexamethasone leaving the last group serving as the control group. The blood alanine transaminase (ALT), total bilirubin (TBil), pathological changes of the graft and survival time of the recipients were observed. RESULTS: The recipients with apoptotic donor spleen cell infusion had much higher ALT and TBil levels than those of the other 3 groups (P<0.05), exhibiting significantly shortened survival time and severer acute allograft rejection, as compared with the mild acute rejection in the control group (P<0.01). CONCLUSION: Simultaneous injection of apoptotic donor spleen cells induced by dexamethasone in rats with liver transplantation aggravates acute allograft rejection, one of the possible mechanisms of which may lie in the failure of timely removal of the apoptotic cells that release inflammatory factors.

Alanine Transaminase↗
PubMed2003

[Surveillance finding on rotavirus in Changchun children's hospital during July 1998-June 2001].

OBJECTIVE: To establish baseline patterns of rotavirus diarrhea and to describe its epidemiologic features in Changchun city, prior to rotavirus vaccine immunization. METHODS: Hospital-based surveillance was conducted among children under 5 years old with acute diarrhea in Changchun Children's Hospital. Fecal samples were determined to identify rotavirus by PAGE and/or ELISA. G serotypes of rotavirus were identified by ELISA and/or nested RT-PCR. P genotyping were carried out by RT-PCR. All data were computerized and analysed by "Generic Manual on Rotavirus Surveillance" set by CDC in the USA. RESULTS: In total, 2 343 diarrhea cases were screened and 1 211 fecal samples were collected. Rotavirus was detected in 31.0% among outpatients and 52.9% in inpatients. During the peak of the season (November through March), 58.6% of diarrhea was caused by rotavirus among inpatients. 95.0% of rotavirus diarrhea cases occurred among children aged < 2 years. The predominant strain was serotype G1 (82.4%), followed by G2 (5.0%), G3 (3.3%), G4 (0.9%). P genotyping showed that P[8] and P[4] were the most common ones. Nine different P-G combinations were identified, four strains (P[8]G1, P[4]G2, P[8]G3, and P[8]G4) commonly seen worldwide accounted for 75.6% of the total. Taken together with uncommon strains, including the novel types P[4]G4 and P[8]G2, it highlights the extraordinary diversity of rotaviruses circulating in China. CONCLUSION: Rotavirus is the major cause of severe child diarrhea in Changchun. Developing a rotavirus vaccine for prevention of severe disease and reduction of treatment costs seemed to be necessary.

Child, Preschool↗
PubMed2003

[Combined use of TUVP and TURP for treating BPH (report of 179 cases)].

OBJECTIVE: To investigate a new operation method for the treatment of benign prostate hyperplasia(BPH). METHODS: One hundred and seventy-nine patients with BPH were treated by the combined use of transurethral electrovaporization ablation of the prostate(TUVP) and transurethral resection of the prostate(TURP). RESULTS: The procedure was successful and the results were satisfactory, with little bleeding and no serious complication. IPSS decreased from 29.0 preoperatively to 7.6 postoperatively (P < 0.05) and Qmax increased from 5.8 ml/s preoperatively to 14.8 ml/s postoperatively(P < 0.05). CONCLUSIONS: The combined use of TUVP and TURP is a safe, effective and ideal method for the treatment of BPH.

Aged↗
PubMed2003

[Effects of solid adsorbents on the emission of heavy metals during coal combustion].

Experiments were carried out on laboratory-scale pulverized coal combustion with different adsorbents. Three solid adsorbents (calcium sulfate, limestone and bauxite) were used to control the emission of heavy metals (Pb, Cd, Cu, Co, Ni) during coal combustion. Sequential extraction procedure was developed for partitioning of metals species in coal ash into five fractions: absorbable metals, exchangeable metals, metals bound to carbonate, metals bound to sulfate, residual metals. The adsorbents showed a certain adsorptive ability to heavy metals, and different adsorbent had different ability. It can be proved from the distribution of heavy metals between coarse ash residues and fine particles and also from the increment of stable speciation of heavy metals in fine particles. Calcium sulfate was effective sorbent for removal of Pb, Cd and Cu, limestone for removal of Pb, Cd, Cu, Ni, and bauxite for removal of these five heavy metals. Fine adsorbents have higher adsorptive ability than coarse adsorbents.

Adsorption↗