Objective To investigate the levels of cytokines in sera of patients with various types of psoriasis.Methods Six cytokines, sIL-2R、 IL-2、 -4、 -10、 -12 and IFN-γ , were detected by sandwich ELISA in the sera from 15 patients with guttate psoriasis, 23 plaque psoriasis, 9 pustular psoriasis, 9 arthropathic psoriasis and 9 erythrodermic psoriasis.Results Significantly higher levels of cytokines were observed in guttate psoriasis for sIL-2R (P<0.01), in plaque psoriasis for IL-4,-12 and sIL-2R (P< 0.05 or < 0.01), in pustular psoriasis for IL-4 and -10 (P< 0.05), in arthropathic psoriasis for IL-10 (P< 0.01), in comparison with the controls.The levels of the six cytokines were increased in erythrodermic psoriasis with no significant difference from the controls.The ratio of the average level of IL-4 to IFN-γ was 1.57 in pustular psoriasis, 0.61 in plaque psoriasis, 0.30 in gutatte psoriasis, 0.24 in erythrodermic psoriasis, and 0.02 in arthropathic psoriasis.Conclusion There is different expression of cytokines in sera of patients with various types of psoriasis.

We report the results of detecting M. lepraespecific antigen--phenolic glycolipid I (PGL--I) with modified M-Dot-ELISA in sera from 75 cases of household contacts (HC)of leprosy patients, which were all seropositive by Gelatin Particle Agglutination Test (MLPA)and ELISA. The results indicate that: (1 ) 16/75 (21. 3 % ) are antigen positive. The rates of positivity in HC of MB patients are much higher than those in HC of PB patients,the difference (P

Objective To develop a rapid method with high sensitivity and specificity to detect Mycobacterium avium.Methods A polymerase chain reaction(PCR)was developed.Its sensitivity and specificity were verified by sequential dilution of DNA of M.avium and other17Mycobacterium spp.,respectively.Simulation of clinical infection was established by mixing normal skin tissue with M.avium.The treatment of the tissue specimens was optimized in order to improve the sensitivity of the PCR assay.Results A fragment of427bp was amplified by the PCR assay with the strains of M.avium at the sensitivity of1?10 2 cells/mL.The other17Mycobacterium spp.were all negative.The sensitivity of the PCR assay decreased to1?10 4 cells/mL when M.avium was mixed with the homogenized skin tissue.The sensitivity recovered to1?10 2 cell/mL when the skin tissue was diluted to≥1∶4.Conclusion It is suggested that PCR be a rapid and reliable method for detection of M.avium.

Objective To establish a polymerase chain reaction(PCR) method to amplify DNA of M.leprae from fixed and paraffin－ embedded tissue(FPET). Methods The DNA of M.leprae was released from FPET by using Texpat Kit and purified with 100％ alcohol. The primers RPOT(1) and RPUT(2) were used to conduct the PCR. Results A total of 32 samples were examined. Out of 32 samples with BI of more than 1＋ , 28 were positive for PCR. The PCR was negative in a sample with BI=0. The sensitivity of PCR reached a level of 0.04 pg DNA. Conclusion This PCR method is very useful for amplifying the DNA of M.leprae from FPET.

Objective To explore whether there were differences in genotypes between strains of M.leprae in China or not. Methods Polymerase chain reaction (PCR) was used to detect the genotypes of M.leprae in samples from patients with leprosy in different parts of China. Results Out of 16 samples from 9 provinces, 91 bp DNA fragments were present in 7 samples and 97 bp DNA fragments in 9 samples. Conclusion Above- mentioned results suggest the genotyping differences in strains of M.leprae with different distribution in areas of China.

Objective To investigate the levels of cytokines in sera of patien ts with various types of psoriasis. Methods Six cytokines, sIL－2R、 IL－2、－ 4、－10、－12 and IFN－? , were detected by sandwich ELISA in the sera from 15 patients with guttate psoriasis, 23 plaque psoriasis, 9 pustular psoriasis, 9 arthropathic psoriasis and 9 erythrodermic psoriasis. Results Significantly hig her levels of cytokines were observed in guttate psoriasis for sIL－2R (P

Objective To investigate the imbalance between T helper 17 (Th17) cells and CD4+CD25+ regulatory T (Treg) cells in the peripheral blood of patients with psoriasis vulgaris and its significance. Methods Peripheral blood were collected from 48 patients with psoriasis vulgaris and 32 normal human controls. Pasoriasis area and severity index (PASI) was used to assess the disease severity in these patients. Flow cytometry was performed to determine the percentage of Th17 and Treg cells in peripheral blood, enzyme linked immunosorbent assay (ELISA) to measure the levels of serum interleukin (IL) -17 and IL-10. Results There was a significant increase in the percentage of Th17 cells [(2.70 ± 1.43)% vs. (0.86 ± 0.25)%, P< 0.01] and serum IL-17 level (90.65 ± 29.61 ng/L vs. 48.82 ± 5.49 ng/L, P < 0.01), but a decrease in the percentage of Treg cells [(3.63 ± 1.14)% vs. (7.87 ± 1.26)%, P< 0.01] and serum IL-10 level (17.78 ± 4.09 ng/L vs. 23.76 ± 3.82 ng/L, P <0.01) in patients with psoriasis vulgaris compared with the normal controls. The ratios of Thl7 to Treg cells and serum IL-17 to IL-10 level were significantly higher (0.95 ± 0.76 vs. 0.12 ± 0.06, 5.78 ± 3.19 vs. 2.16 ±0.68, both P < 0.01) in the patients than in the normal controls. The PASI score in patients was positively correlated with the percentage of Th17, serum level of IL-17, Th17/Treg ratio and IL-17/IL-10 ratio (r = 0.97,0.93, 0.99 and 0.97, all P < 0.01), but negatively correlated with the percentage of Treg cells and serum IL-10 level (r = -0.87, -0.90, both P < 0.01). Conclusion The imbalance between Th17 and Treg cells may play an important role in the pathogenesis of psoriasis vulgaris.

Objective To genotype the clinically isolated strains of M.leprae by genome sequencing analysis. Methods PCR amplification was used to produce the 200 bp partial rpoT gene fragments from 2 standard strains and the isolated strains of M. leprae isolated from clinical specimens in 7 areas of China. The fragments were sequenced by BigDye Terminator Cycle Sequencing Reaction kit. Results① 12 rpoT－ 91/97bp DNA fragments and 2 rpoT－ 194/200 bp DNA fragments were obtained from 13 clinically isolated strains of M. leprae by PCR amplification;② based upon genome sequencing analysis, a component of 3－ copy or 4－ copy“ GACATC” repeat sequence was found in the nucleotide sequence of rpoT－ 194/200 bp DNA fragment. Conclusion The genome sequencing analysis can be used to objectively and accurately genotype M.leprae, and it is a useful tool for epidemiological study on transmission and infection of leprosy. However, the longer DNA fragments are necessary when sequencing analysis is conducted. Therefore this method needs further improvement because only the shorter DNA fragments amplified from paraffin－ embedded tissue.

Objective To develop a rapid method with high sensitivity and specificity to detect 4 mycobacterial species(M. tuberculosis, M. avium, M. intracellulare and M. kansasii) which are the most common opportunistic Mycobacteria in AIDS patients. Methods The sensitivities and specificities of PCR were determined with different primer pairs targeting various mycobacterial genes. Multiplex PCR with combination of 4 primer pairs was used to detect the template mixtures of either 1, 2 or 3 mycobacterial DNA. Sensitivities of multiplex PCR were measured. Results Specific DNA fragments of 4 mycobacterial species mentioned above could be detected by PCR and sensitivities ranged from 1 ? 101 ~ 1 ? 102 cells/mL, while the other 17 mycobacterial strains were all PCR-negative. Multiplex PCR could amplify the corresponding 1, 2 or 3 DNA fragments, depending on the number of template DNA added, and sensitivities of multiplex PCR ranged from 1 ? 102 ~ 1 ? 103 cells/mL. Conclusions Multiplex PCR is a rapid, sensitive and specific method for differentiation and detection of Mycobacteria.

Objective To develop a PCR-RFLP method for the identification of eight mycobacterial species. Methods PCR was performed targeting the gene encoding 65-kDa heat shock protein which was common to all mycobacteria. Two restriction enzymes, BstE Ⅱ and Hae Ⅲ, were used to digest the PCR products, and specific restriction patterns of different mycobacteria were obtained. Results The specific restriction patterns of different mycobacteria were identical to the data previously reported. Conclusion We could differentiate M. avium, M. intracellulare, M. kansasii, M. tuberculosis, M. scrofulaceum, M. marinum, M. fortuitum and M. chelonae in one experiment by PCR-RFLP.