Biomedical subjects

Hong Lu

Publications and source records attributed to Hong Lu.

122 records · Page 7Linked to original sources

PubMed2002

RePS: a sequence assembler that masks exact repeats identified from the shotgun data.

We describe a sequence assembler, RePS (repeat-masked Phrap with scaffolding), that explicitly identifies exact 20mer repeats from the shotgun data and removes them prior to the assembly. The established software is used to compute meaningful error probabilities for each base. Clone-end-pairing information is used to construct scaffolds that order and orient the contigs. We show with real data for human and rice that reasonable assemblies are possible even at coverages of only 4x to 6x, despite having up to 42.2% in exact repeats.

Cloning, Molecular↗

PubMed2002

Analysis of microdissected prostate tissue with ProteinChip arrays--a way to new insights into carcinogenesis and to diagnostic tools.

Prostate carcinomas are one of the most common malignancies in western societies. The pathogenesis of this tumor is still poorly understood. These tumors present with two characteristic features: epithelial-mesenchymal interactions, which play a pivotal role for tumor development and most of clinically manifest cancers arise in prostate proper compared to a minority of tumors which develop in the transitional zone. Deciphering the epithelial-mesenchymal cross talk and identification of molecular pecularities of the sub-populations of cells in different zones can therefore help understanding carcinogenesis and development of new, non-invasive tools for the diagnosis and prognosis of prostate carcinomas which has remained a challenge until today. A ProteinChip array technology (SELDI = surface enhanced laser desorption ionization) has been developed recently by Ciphergen Biosystems enabling analysis and profiling of complex protein mixtures from a few cells. This study describes the analysis of approximately 500-1000 freshly obtained prostate cells by SELDI-TOF-MS (surface enhanced laser desorption ionization time-of-flight mass spectrometry). Pure cell populations of stroma, epithelium and tumor cells were selected by laser assisted microdissection. Multiple specific protein patterns were reproducibly detected in the range from 1.5 to 30 kDa in 28 sub-populations of 4 tumorous prostates and 1 control. A specific 4.3 kDa peak was increased in the prostate tumor stroma compared to normal prostate proper and transitional zone stroma and increased in prostate tumor glands compared to normal prostate proper and transitional zone glands. Coupling laser assisted microdissection with SELDI provides tremendous opportunities to identify cell and tumor specific proteins to understand molecular events underlying prostate carcinoma development. It underlines the vast potential of this technology to better understand pathogenesis and identify potential candidates for new specific biomarkers in general which could help to screen for and distinguish disease entities, i.e. between clinically significant and insignificant carcinomas of the prostate.

Aged↗

PubMed2002

Effects of bicyclol on aflatoxin B1 metabolism and hepatotoxicity in rats.

AIM: To study the effect of new antihepatitis drug, bicyclol, on the metabolism and hepatotoxicity of aflatoxin B1 (AFB1) in rats. METHODS: Rats were given bicyclol 300 mg/kg/d ig for 3 d and then injected ip with AFB1 1.5 mg/kg. Liver damages were examined 16 h after ip AFB1. The in vitro metabolism of AFB1 by bicyclol-pretreated liver microsomes was investigated by HPLC assay. RESULTS: Bicyclol (300 mg/kg/d for 3 d) pretreatment provided protection against AFB1 hepatotoxicity as evidenced by the decrease of AFB1-elevated serum aminotransferase and hepatic malondialdehyde in rats. Bicyclol pretreatment slightly increased the production of the less toxic metabolite aflatoxin Q1. Bicyclol increased liver cytochrome P450 content, CYP 2B1-mediated 7-pentoxyresorufin O-dealkylase (PROD) activity, cytosolic glutathione (GSH) level, and GSH S-transferase (GST) activities. Moreover, bicyclol increased CYP 3A-mediated erythromycin-demethylase and CYP 1A-mediated 7-ethoxyresorufin O-deethylase (EROD) activities. CONCLUSION: Bicyclol protected rats against AFB1 hepatotoxicity by increasing the detoxifying metabolism of AFB1 in the liver.

Aflatoxin B1↗

PubMed2002

Influence of abnormal cervical pap smear undertaken during pregnancy to the outcome of the pregnancy.

OBJECTIVE: To investigate the influence of abnormal cervical pap smear undertaken in pregnancy to the outcome of the pregnancy. METHODS: A total of 1 069 primipara deliveried in Beijing Chaoyang hospital from Jan 1999 to May 2001 were reviewed, furthermore we compared the group of normal pap smear (group A) with the group of abnormal pap smear (group B), and analysed the difference of the complications during pregnancy, methods of delivery, the first stage of labor, fetal distress and the outcome of the cervical pap smear postpartum. RESULTS: The incidence of premature rupture of the membranes and fetal distress in group B, which were 39.39% and 30.30%, respectively, were significantly higher than that of group A, which were 5.21% and 15.25%, respectively (P < 0.01). There was no statistical difference in premature delivery, the ratio of cesarean section and the first stage of labor which were 3.38% and 3.03%, 44.11% and 30.30%, 7.3 h and 7.7 h, respectively (P > 0.05). The regression rate for patients with abnormal cervical pap smear postpartum was 62%. CONCLUSIONS: The outcomes of the pregnancy such as premature rupture of the membranes and fetal distress were affected by the abnormal cervical pap smear undertaken during pregnancy. It is important to undergo routine cervical pap smear examination during pregnancy.

Female↗

PubMed2002

[The systemic manifestations of ulcerative colitis].

OBJECTIVE: To probe the relationship between location and extent of ulcerative colitis (UC) by analyzing its extra-intestinal manifestations. METHODS: 392 UC cases in Peking Union Medical College Hospital from 1976 to 2000 were reviewed retrospectively. Chi-square test was used to test the difference between groups. RESULTS: 82 of 392 patients (20.9%) with UC had extra-intestinal manifestations, 34 (8.7%) of these patients had more than one extra-colonic organ involvement; It shows that the extensive colitis has highest incidence of extra-intestinal manifestations with UC than that of the left-sided colitis did, while the proctitis had the lowest incidence. There were no significant difference (P > 0.05) between the group of extensive colitis and that of left-side colitis; The incidence of extra-intestinal manifestations in severe cases was significantly greater than that in mild cases. There was a trend of increasing incidence from severe to moderate to mild type (P < 0.05); Most of the extra-intestinal manifestations were associated with active UC, except for AS, PSC, healed during SASP and/or steroid treatment. CONCLUSIONS: Extra-intestinal manifestations had a high incidence in UC. The most frequently involved organs were joints, hepatobiliary system, skin, mouth and eyes. The majority of them were associated with the active UC. The incidence of extra-intestinal manifestations with UC was closely related with the extent and severity of the lesions, and the most of the extra-intestinal manifestations occurred in the active phase of UC. But the incidence of extra-intestinal manifestations was not related to prognosis.

Adolescent↗

PubMed2002

[Bone graft repair of adolescence spondylolysis with lag screw and tension band fixation].

OBJECTIVE: To investigate direct bone graft repair with lag screw and tension band fixation technique and its value for the treatment of adolescence spondylolysis. METHODS: Lysis was prepared and the fibrous tissue within the gap was removed in 12 patients from 12 to 26 years (average 18.4). 1 - 2 mm extra bony element was resected on both sides with fresh interface with the bone graft harvested from the iliac crest. From the entry point 8 mm away from the midline at the inferior margin of the lamina, titanium lag screws of 35 - 45 mm long and 3.5 mm in diameter were placed at 300 upward and outward and tighted through the lysis, bone graft and the superior and lateral aspect of the pedicle. Extra match bone graft was placed around the surface of defect, an high intensity Nilon wire tension band between the cap of the screw and the basis of transverse process was constructed before wound closure and suction drainage. The patients were immobilized with plaster brace of Paris for 2 months. RESULTS: Average operation time was (10 +/- 55) minutes, and average blood loss was 170 ml. Follow-up ranged from 12 to 36 months (mean 17 months), and cases of 22 lysis healed within 3 months. CONCLUSIONS: Technique of direct bone graft repair with lag screw and tension band fixation for the treatment of adolescence spondylolysis is simple, safe and reliable. Combined biomechanical and biological processes, it is less invasive but advantageous in preserving the motion in the affected segment.

Adolescent↗

PubMed2002

Effects of dimethyl diphenyl bicarboxylate on the metabolism and hepatotoxicity of aflatoxin B1 in rats.

AIM: To study the effect of antihepatitis drug, dimethyl diphenyl bicarboxylate (DDB) on the metabolism and hepatotoxicity of aflatoxin B1(AFB1) in rats. METHODS: Rats were given orally DDB 300 mg.kg-1.d-1 for 3 days and then injected intraperitioneally with AFB1 1.5 mg.kg-1. Serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were examined 16 hours after the injection of AFB1. The in vitro metabolism of AFB1 by DDB-pretreated rat liver microsome was investigated by HPLC assay. RESULTS: DDB (300 mg.kg-1) pretreatment provided significant protection against AFB1 hepatotoxicity as evidenced by the decrease of AFB1-elevated serum marker enzymes in rats. Pretreatment with DDB was shown to slightly increase the level of AFM1, the less toxic metabolite. DDB significantly increased the liver cytochrome P450 content, P450 isozyme 2B1-mediated 7-pentoxyresorufin O-dealkylase (PROD) activity, cytosolic glutahione (GSH) level and GSH S-transferase (GST) activities. In addition, DDB slightly increased P450 isozymes, 3A-mediated erythromycin-demethylase and 1A-mediated 7-ethoxyresorufin O-deethylase (EROD) activities. CONCLUSION: The results indicate that DDB protected rats against AFB1 hepatotoxicity by increasing the detoxifying metabolism of AFB1 in the liver.

Aflatoxin B1↗

PubMed2002

[Fourier transform infrared spectroscopy study on the protein secondary structure of photosystem II reaction center].

A successful study on the secondary structure of the isolated photosystem II (PSII) particles with the Fourier transform infrared spectroscopy is reported in this paper. The beta condensation effect is obviously characterized by infrared absorption spectra. The infrared spectra of both living protein and beta condensed protein samples are measured at room temperature. The amide I band in infrared spectrum is used to perform the quantitative analysis of the sample properties. The recorded spectra show the irreversible effect for the PSII particles after the 400 K heating. A rather strong change of the infrared spectra is observed due to the beta condensation of PSII protein. All the spectra are well fitted by 3-Lorentz-peak. The FTIR spectroscopy shows its effectiveness in studying the heating effect on the PSII particles.

Amides↗

PubMed2002

[The changes of soluble interleukin-2 receptor in serum and cerebrospinal fluid of patients with delayed encephalopathy after acute carbon monoxide poisoning].

OBJECTIVE: To explore the changes of soluble interleukin-2 receptor(sIL-2R) in serum and cerebrospinal fluid (CSF) of patients with delayed encephalopathy after acute carbon monoxide poisoning (DEACMP). METHODS: There were 31 patients with DEACMP, 32 patients with other encephalopathy and 31 controls in this study. The levels of sIL-2R in serum and CSF were detected by ELISA. RESULTS: Serum sIL-2R in patients with DEACMP[(329.21 +/- 160.99)U/ml] was significantly higher than that in control[(115.67 +/- 89.58) U/ml, P < 0.05)], but not significantly different from that in the other encephalopathy group[(367.50 +/- 123.14) U/ml, P > 0.05)]. CSF sIL-2R in patients with DEACMP[(54.48 +/- 43.04) U/ml] measured a little before discharge was significantly lower than that in patients with the other encephalopathy[(110.24 +/- 76.56) U/ml, P < 0.05)], but not significantly different from that in the control group[(34.96 +/- 22.70)U/ml, P > 0.05)]. At the pre-discharged period, CSF sIL-2R in patients with DEACMP[(100.26 +/- 93.65) U/ml] was significantly higher than that at the early stage of hospitalization[(52.28 +/- 43.31) U/ml, P < 0.05)]. No significant difference in serum sIL-2R was found between early stage of hospitalization[(338.34 +/- 161.53) U/ml] and pre-discharge [(351.31 +/- 175.93) U/ml, P > 0.05)]. CONCLUSION: The occurrence of DEACMP may be related with immunopathological damage. The sIL-2R levels in serum and CSF may give information about the state of immunological function of the patients with DEACMP and may contribute to determining the patient's condition and prognosis.

Brain Diseases↗

PubMed1999

Activity of Lipase in Reversed Micelles.

The enzyme activity of lipase from Candida rugosa in AOT isooctane reversed micelles was investigated. Effect of pH, temperature, substrate concentration, waterpool (R value), choice of organic solvent, surfactant concentration on the activity of lipase were studied in detail. Results indicate that the enzyme in reversed micelles follows the Michaelis-Menten dynamics temperature optimum=32.5 degrees, pH optimum=7.0, and maximum activity is reached at the concentration of olive oil of 40%. The enzyme activity was dependent on R (molar ratio of water to surfactant) and maximum activity was obtained at R=11.

Journal Article↗

PubMed1998

Correlation of Calcium-independent Phosphatidylcholine-specific Phospholipase C with gamma-GT in Hepatoma Cells.

We studied the activities of calcium-independent phosphatidylcholine-specific phospholipase C (PC-PLC) and the relationship between PC-PLC and gamma-GT in hepatoma cells. We noted that PC-PLC activity decreased significantly during hepatocarcinogenesis and the proliferation of CBRH-7919 cells, but increased significantly during differentiation. There was a close relationship between PC-PLC and gamma-GT activities. When CBRH-7919 cells were treated with exogenous PC-PLC, it took only 15 minutes for gamma-GT activity to decrease significantly and to the lowest level at 24 hours. However, gamma-GT activity in culture medium increased within 2 hours, then decreased afterward. We conclude that PC-PLC may regulate gamma-GT via certain pathways.

Journal Article↗

PubMedDate not supplied

Multicenter, randomized, controlled trial of heat-killed Lactobacillus acidophilus LB in patients with chronic diarrhea.

Chronic diarrhea is a common bowel disorder; disturbance of intestinal microorganisms may play a role in its pathogenesis. This study assessed the clinical efficacy of lyophilized, heat-killed Lactobacillus acidophilus LB versus living lactobacilli in the treatment of chronic diarrhea. One hundred thirty-seven patients with chronic diarrhea were randomly allocated to receive either a 4-week course of 2 capsules of Lacteol Fort twice a day (Lacteol group, 69 patients) or a 4-week course of 5 chewable tablets of Lacidophilin three times a day (Lacidophilin group, 64 patients). The frequency of stools was recorded quantitatively, and semiquantitative parameters such as stool consistency, abdominal pain, distention, and feeling of incomplete evacuation were evaluated. At the second and fourth week of treatment, mean bowel frequency was significantly lower in the Lacteol group than in the Lacidophilin group (1.88 +/- 1.24 vs 2.64 +/- 1.12, 1.39 +/- 0.92 vs 2.19 +/- 1.05; P<.05). At the end of the treatment, the clinical symptoms were markedly improved in the Lacteol group, indicating that L. acidophilus LB is more effective than living lactobacilli in the treatment of chronic diarrhea.

Adolescent↗

PubMedDate not supplied

Communication channels to help build an international community of education and practice.

Two-way communication is required if nurses are to build knowledge networks of international communities of nursing education and practice. Are expensive new technologies feasible or preferred for effective communication and productive outcomes? In this report from a longstanding partnership between schools of nursing at Peking University and the University of Michigan, case study methodology is used to evaluate more than a decade of experience with communication modalities: in person, postal mail, express mail, e-mail, fax, telephone, hand delivery by other travelers, and Web sites. Although each education and practice community develops unique ways to build its shared knowledge, a communications plan is suggested, with use of multiple communication techniques, especially those that are low cost and the most dependable. High-cost technologies are not always feasible or preferred. For the project described, they were not necessary to the major outcome, a nursing education and practice network that resulted in the first nurse-managed community-based clinic in China.

China↗

PubMedDate not supplied

Evaluation of "credit card" libraries for inhibition of HIV-1 gp41 fusogenic core formation.

Protein-protein interactions are of critical importance in biological systems, and small molecule modulators of such protein recognition and intervention processes are of particular interest. To investigate this area of research, we have synthesized small-molecule libraries that can disrupt a number of biologically relevant protein-protein interactions. These library members are designed upon planar motif, appended with a variety of chemical functions, which we have termed "credit-card" structures. From two of our "credit-card" libraries, a series of molecules were uncovered which act as inhibitors against the HIV-1 gp41 fusogenic 6-helix bundle core formation, viral antigen p24 formation, and cell-cell fusion at low micromolar concentrations. From the high-throughput screening assays we utilized, a selective index (SI) value of 4.2 was uncovered for compound 2261, which bodes well for future structure activity investigations and the design of more potent gp41 inhibitors.

Amino Acid Sequence↗