Objective:To study the value and advantage of color Doppler and cervical multi-slice spiral CT (MSCT) in the diagnosis of cervical lymphadenopathy.Methods:A total of 130 patients with cervical lymphadenopathy diagnosed and treated in the Chenzhou First People′s Hospital from January 2019 to December 2020 were selected and received color Doppler ultrasound examination and MSCT examination. The results of pathological examination were used as the gold standard to compare the efficacy of the two methods in the differential diagnosis of benign and malignant cervical lymphadenopathy.Results:Ultrasound examination of malignant lymph nodes showed irregular boundaries, uneven internal hypoecho, and abundant blood flow signals in lymph nodes; ultrasound examination of benign lymph nodes showed uniform fine dot echo, uniform growth of endothelial medulla, clear and smooth boundary, no blood flow signal or scattered dot blood flow signal. The MSCT images of malignant lymph node showed irregular shape, blurred edge, obvious and uneven enhancement and higher rate of calcification. The aspect ratio of lymph nodes in benign lymph node was significantly higher than that in malignant lymph node (2.14 ± 0.48 vs. 1.92 ± 0.43), and the maximum blood flow velocity (V max), resistance index (RI) and blood flow (BF) in systolic period were significantly lower than those in lymph node [(21.38 ± 3.61) cm/s vs. (23.17 ± 2.55) cm/s, 0.62 ± 0.14 vs. 0.71 ± 0.17, (48.82 ± 13.51) ml/(min·100 g) vs. (65.61 ± 14.64) ml/(min·100 g)], there were statistical differences ( P<0.05). The most common blood flow types was lymphatic hilum type in benign lymph node, the proportion was 51.79% (29/56), while the most common type in malignant lymph node was marginal type and central type, the proportion was 44.59% (33/74) and 25.68% (19/74). The sensitivity, specificity, accuracy and Kappa value of ultrasound combined with MSCT in diagnosis were 92.86%, 95.95%, 94.62% and 0.890. Conclusions:Both color Doppler ultrasonography and MSCT can differentiate the benign and malignant of cervical lymph node lesions with better parameters such as lymph node imaging characteristics and blood flow distribution pattern, but the combined diagnosis has higher sensitivity, specificity and accuracy.

Objective To compare the performance of 2％ (w/v) agarose gel,2％ (w/v) Metaphor agarose gel and 10％(w/v) nondenaturating polyacrylamide gel in the PCR-restriction fragment length polymorphism (RFLP) analysis of mycobacterial heat shock protein 65 (hsp65) gene.Methods This study included 8 Mycobacteria strains,including clinical isolates and standard strains of Mycobacteria tuberculosis and Mycobacterium intracellulare.Bacterialsuspension of these strains was prepared with the concentration of bacterial cells varying from 10 to 106per milliliter.PCR was performed to amplify the hsp65 gene with a pair of universal primers followed by the digestion of amplicons with two restriction endonucleases,BstE Ⅱ and Hae Ⅲ.Then,the restriction enzyme-digested fragments were subjected to electrophoresis in 2％ agarose gel,2％ Metaphor agarose gel and 10％ nondenaturating polyacrylamide gel respectively.Results As analysis of variance showed,the three gel electrophoresis methods were statistically different in sensitivity for the RFLP analysis of mycobacterial hsp65 gene (F =36.379,P ＜ 0.01).Least significance difference (LSD) procedure revealed that the 2％ agarose gel-based electrophoresis was less sensitive than the 2％ Metaphor agarose gel-and 10％ non-denaturing polyacrylamide gel-based electrophoresis (both P ＜ 0.01),and no significant differences were observed between the 2％ Metaphor agarose gel-and 10％ non-denaturing polyacrylamide gel-based electrophoresis (P ＞ 0.05).Conclusion The 2％ Metaphor agarose gel-and 10％nondenaturating polyacrylamide gel-based electrophoresis methods appear to be more sensitive than the 2％ agarose gel-based electrophoresis method for the PCR-RFLP analysis of mycobacterial hsp65 gene.

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 test the drug susceptibility of 16 Mycobactena tuberculosis isolates from patients with cutaneous tuberculosis,and to provide a basis for the treatment of this entity.Methods Sixteen strains of mycobacterium were isolated from patients with cutaneous tuberculosis.and they were consistently identified as M.tuberculosis by biochemistry and molecular biology.Absolute concentration method was used to test the susceptibility of these isolates to isoniazid.streptomycin.rifampicin and ethambutol.For two strains resistant to streptomycin,PCR and sequencing were performed to analyse the mutation of rpsL gene.Results Out ofthe 16 strains of M tuberculosis.2 were resistant to streptomycin but sensitive to isoniazid,rifampicin and ethambutol,and 14 were sensitive to isoniazid,streptomycin,rifampicin and ethambutol.Sequencing of the rpsL gene revealed a mutation of AAG to AGG at codon 43 in one streptomycinresistant strain and a substitution of CGC bv CAC at codon 54 in another resistant strain.Conclusions In past five years,the resistance ratio of M tuberculosis was low in patients with cutaneous tuberculosis,and streptomycin resistance predominated in these strains.

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 study level of the expression of RAR? mRNA in the skin lesions of patients with psoriasis vulgaris. Methods The biopsies were taken from skin lesions in 20 patients with psoriasis vulgaris and the skin of 10 normal controls, and levels of RAR? mRNA were investigated with RT-PCR. Results The level of RAR?mRNA was significanlly lower in the epidermis of patients with psoriasis vulgaris than that in the control(P

1), attributable risk (AR)=13.33%; ⑤Even though the serum specimens were taken from PB patients, the Ab of majouity of patients converted to positive when relapse occurred. In the majority of patients relapsed the levels of IgM-AbL tended to be increasing or pesistently positive. Usually relapse occurred 1-2 years after IgM-AbL was converted to positive. Relapse occurred 11-30 years after the patients were cured. In very rare case downgrading(from tuberculous to borderline leprosy) occurred. ⑥The levels of IgM-AbL gradually decreased in all relapsed patients after effective treatment except one case whose IgM-AbL was persistently positive. Conclusions The above results indicate that the ND-ELISA might be useful in screening early M.leprae infection and in predicting and monitoring the relapse of leprosy, especially in multibacillary patients.

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.

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.

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.