Human African trypanosomiasis is caused by the infection of Trypanosoma brucei gambiense or T.b. rhodesiense, while another morphologically identical subspecies, T.b.brucei, and other closely related species, T.equiper-dum and T.evansi, are considered not infectious to human. This is highly related to the trypanosome lytic factor (TLF) found in normal human serum (NHS) and the serum resistance-associated (SRA) protein of trypanosomes infectious to human. We reviewed the research progress in TLF and its role in trypanosome lysis as well as the mechanism of SRA against the TLF.

Objective To clone the genes coding for cysteine proteases (CPs, TvCPs) from Trichomonas vaginalis and to analyze their genetic variations with the related sequences from NCBI database (GenBank) and T. vaginalis Genome Project database from The Institute for Genomic Research (TIGR). Method TvCP genes were amplified using PCR, and inserted into vector pET28b or pBS-T. The recombinant plasmids were then transformed to Escherichia coli BL21 or Top10 strain. The recombinant plasmids were used for sequencing. Homologous TvCP genes were blasted based on NCBI GenBank and TIGR T. vaginalis Genome Project database. The sequences of cloned TvCP genes were aligned and clustered by Clustal X (1.83 version) with retrieved sequences. Comparisons of amino acids among cathepsin L-like TvCPs, human L-like cathepsins and papaya papain were performed using DNAstar software, and their phylogenic tree was constructed based on neighbor-joining method using Clustal X. Results Two TvCP3 clones and one TvCP2 had a high identity of more than 99% with their responding TvCPs. Three clones of TvCP4 genes, GZ-CP4-clone 1-3, belonged to two members of a family showing a high percentage identity of more than 97.5% with the sequences of TvCP4 genes from databases (GenBank and TIGR) both at amino acid and nucleotide levels. Nine homologous TvCP4 pro-enzymes with 304 amino acids and other two members with deletions of N-terminal sequence existed in T. vaginalis sharing a similarity of 62.3-96.7% amino acids, which may evolve by means of gene replication and deletion. TvCP1-4, TvCP12, TvCP25 and CP65 had an identity of 61-88.2% at amino acid levels. So far, all reported sequences of C1 family from T. vaginalis belonged to capanthesin L-like subfamily with the same enzymatic active sites, conserved cysteine residues and similar structural features such as ERFNIN-like motif in pro-enzyme region, suggesting that they might result from gene duplication and mutations. Conclusion TvCPs belong to cathepsin L-like family with genetic diversity, but they have the same active amino acid residues, cysteine residues and similar structural characteristics, suggesting that they may derive from one ancestor.

Adolescent ; Adult ; Child ; Child, Preschool ; China ; epidemiology ; Hepatitis B ; epidemiology ; Humans ; Infant ; Middle Aged ; Risk Factors ; Seroepidemiologic Studies ; Young Adult

Objective To observe the effects of long-term hemodialysis(HD) combined with hemoperfusion(HP) on the levels of protein-bound uremic toxins (PBUTs) in maintenance hemodialysis (MHD) patients.Methods Forty-six patients with MHD were selected and divided into HD +HP group and HD group .HD+HP group ( n=22 ) was treated with low-flux HD twice a week and HD combined with HP once a week ,while HD group(n=24) was treated with low-flux HD three times a week.The follow-up lasted 36 weeks.The pre-dialysis concentration of PBUTs was measured at week 12, 24, 36 and baseline.PBUTs included hippuric acid (HA), indoxyl sulphate (IS)and p-cresyl sulphate (PCS).High performance liquid chromatography-tandem mass spectrometry ( HPLC-MS/MS) was used for determination .Results After 36 weeks of follow-up, the concentration of the three toxins in the HD +HP group was lower than that in the HD group during the study.At the end of the study, the reduction rates of HA, IS and PCS were 33.5%,12.8% and 24.2%, respectively, in HD+HP group.The three toxins in HD group increased by 2.3%,21.8%and 2.8%.The clearance rate of HA, PCS and IS in the HP+HD group was higher than in HD group (P<0.05).Conclusion Long-term HD combined with HP can more effectively remove PBUTs , and keep them at a lower level .

China ; Cost of Illness ; Demography ; Female ; Humans ; Maternal Mortality ; Poverty Areas

Objective： There were variations of EBV genome from different areas and they may affect the biologic function of EBV (such as LMP1). EBV-BARF0 was highly detected in the patients with nasopharyngeal carcinoma(NPC) and it s variations have not been reported. This study was designed to determine the sequence and variation of EBV-BARF0 gene in the patieats with NPC from Guangdong area. Methods： PCR was used to amplify the EBV-BARF0 gene in 20 patients with NPC and the productions were sequenced on the ABI377. Results： Comparing with standard B95-8, there were four loci with variances including： 160473 （ G→ T） , 160545 （ C→ T） , 160701 （ C→ A） , 160707 （ G→ C） of sequences and 2 （ Ala→ Ser） , 26 （ Leu→ Phe） , 78 （ Arg→ Ser） , 80 （ Ala→ Pro） of amino acid in 20 patients with NPC. Conclusion： Since the BARF0 gene of EBV is expressed in all nasopharyngeal carcinoma cell line and biopsies, but it is not expressed or less frequenly in lymphoma tissues and cell lines,the authors firstly reported the variation of EBV-BARF0 which compared with B95-8 in the patieats with NPC from Guangdong area. These suggest that the gene may play an important role in the carcinogenesis and development of nasopharyngeal carcinoma.

Adolescent ; Adult ; Aged ; Animals ; Case-Control Studies ; Child ; Child, Preschool ; China ; epidemiology ; Ecosystem ; Female ; Humans ; Male ; Middle Aged ; Mycoplasma ; isolation & purification ; pathogenicity ; Mycoplasma Infections ; epidemiology ; Rural Population ; Young Adult

Adolescent ; Adult ; Antibodies, Viral ; blood ; Female ; Hemagglutination Tests ; Humans ; Influenza A virus ; immunology ; Influenza B virus ; immunology ; Influenza Vaccines ; classification ; immunology ; Influenza, Human ; immunology ; prevention & control ; Male ; Middle Aged ; Safety

OBJECTIVETo evaluate the effect of treatments with the molecular adsorbents recirculating system (MARS) on liver failure patients of severe hepatitis B, in order to seek a safe and effective therapeutic method which contribute to the improved survival rate for severe hepatitis patients.

METHODS52 liver failure patients of severe hepatitis B were performed intermittent MARS therapy for 6 to 8 hours per time in addition to standard medical treatment. Parameters in blood chemical data were collected before and after every treatment and analyzed in comparison with those parameters from controlled groups by means of plasma exchange and standard medical therapy.

RESULTSMARS therapy achieved a remarkable improvement in clinical symptoms and physic signs, accompanied with a significant decrease in serum bilirubin, ammonia, urea nitrogen, fragrant amino acid, endotoxin, IL-6, and TNF-alpha levels (0.05); at the 72 hours bilirubin rebounding analysis. MARS treatments resulted in a significant decrease of bilirubin rebounding level in comparison with what PE did (0.01 ), though the bilirubin removal efficiency between two groups was not statistically significant. The overall survival rate of MARS therapy was 50% (26/52), which was better than that of standard medical therapy (40.5%, 17/42, P less than 0.05).

CONCLUSIONThe results indicated that MARS was a safe and promising technology in the field of liver support therapy. It might be associated with considerable improved survival rate for liver failure patients.

Adult ; Female ; Hepatitis B ; complications ; Humans ; Liver Failure ; blood ; mortality ; therapy ; Male ; Renal Dialysis ; Sorption Detoxification ; Survival Rate

OBJECTIVETo investigate the health and work status of traffic policemen in a city, and analyze the effect of the occupation on health of them.

METHODSThe prevalent investigation was used to investigate the health status of on-the-job traffic policemen and the effect of the occupation on the health of traffic policemen was studied.

RESULTSAmong 4486 traffic policemen, 1604 working outside. The average time of working outside was (12.0 +/- 7.9) years and the average time of standing was (7.0 +/- 1.7) hours/day. The incidence of naso-pharyngitis, arthropathy, photosensitive dermatitis, heat stroke and chilblain, noise-induced deafness in the outside-traffic policemen were higher than that of the policemen working indoors. Eye diseases were higher in those who worked outside for 20-25 years. The varicosis of the lower extremity was higher in those who stood outside over 4 hours every day. The average period of onset of disease was 7-8 years.

CONCLUSIONThe occupational stress of outside-traffic policemen was bigger in the city. The environmental pollution and the bad condition are the risky factors of 8 kinds of diseases among traffic policemen. The average period of onset of the disease is 7-8 years.

Adult ; China ; Female ; Health Status ; Humans ; Male ; Middle Aged ; Occupational Diseases ; epidemiology ; Occupational Exposure ; Occupational Health ; Police ; Urban Population ; Young Adult