BACKGROUND: Polymorphism in promoter region can change the expression of genes, which may be associated with susceptivity of diseases. Gene polymorphism of interleukin-6 (IL-6) promoter is associated with nationality and many diseases. Different nationalities often display different characteristics of gene polymorphism.OBJECTIVE: To observe the distribution of polymorphism at sites -597 and -572 in IL-6 promoter region in Tibet Tibetan population and to provide the theoretical data for Tibetan population genetics and background of immunity.DESIGN: Randomized investigation.SETTING: Institute of Anthropology, Jinzhou Medical College.PARTICIPANTS: Totally 108 healthy Tibetan teenagers were selected from Lasa and Naqu region in Tibet autonomous region from October 2003 to July 2004, including 60 males and 48 females, aged from 14-21 years. Inclusive criteria:The parents of the volunteers were healthy Tibetans after body examination. The volunteers knew the fact, agreed to participate into the trail and signed the informed consent.METHODS: 5 mL peripheral vein blood was collected from 108 Tibetan teenagers. DNA from human leucocytes was extracted by salt fractionation. IL-6 promoter including -597 and -572 fragments was amplified by polymerase chain reaction (PCR). Representative fragments were cloned then sequenced after restriction fragment length polymorphism (RFLP).MAIN OUTCOME MEASURES: Distribution of polymorphism in Tibet Tibetan population; Results after comparison with those of other nationalities including Han population.RESULTS: Data of 108 Tibetan teenagers were involved in the result analysis. ①Distribution of polymorphism on -572C/G site of IL-6 promoters in population of either sex: There were no GA and AA genotypes at site -597, but only GG genotype appeared. There were CC, CG and GG genotypes at site -572, and the frequencies were 0.63, 0.35 and 0.02 in order. Distribution of genotype with representativeness met the Hardy-Weinberg equilibrium. Allele frequencies were 0.81 and 0.19, respectively. There was no significant difference of either sex in genotype and allele frequency (P ＞ 0.05). ②Distribution of polymorphism on -597 G/A and -572 C/G in different nationalities: GG, GA, AA genotypes appeared on -597 site in England and France, and G and A allele frequencies were 0.60 and 0.40,respectively. It was significantly different from that of Tibetan in Tibet. Furthermore, Japanese had no polymorphism,which was similar to that of Hans in China (P ＞ 0.05). ③Genotype of different straps and results of DNA sequencing:Only GG genotype was found on -597 site (without the restriction site, one fragment after restriction, PCR amplification products), no GA and AA genotypes. CC, CG and GG genotypes appeared at site -572, and frequencies were 0.64,0.35 and 0.01, respectively. Distribution of genotype with representativeness met the Hardy-Weinberg equilibrium (P ＞0.05). Allele frequencies were 0.81 and 0.19, respectively. There was no significant difference of either sex in genotype and allele frequency. Distribution of gene frequency and allele frequency in IL-6 were similar between Tibetan and that of Hans, but it was significantly different from that of population in England, France and America.CONCLUSION: There are nationality differences of IL-6 gene polymorphism at sites -597 and -572. No polymorphism is found at site -597 in Tibetan. Race differences are seen at site -572, having CC, CG and GG genotypes and G allele is rate. Compared with white population, there is significant difference in genotype and allele frequency at site -572. Their characteristics are close to Hah population and Japanese, which may be associated with genetic gene of persons living in plateau.

Objective To explore the imaging features of papillary thyroid microcarcinoma(PTMC) with real time contrast-enhanced ultrasound.Methods One hundredand forty-three cases with 149 thyroid nodules(no diffuse lession) were divided into two groups according to the diameter size(group 1,＜0.5 cm;group 2,0.5-1.0 cm) and examined by contrast-enhanced ultrasound during preoperation.Pathology was followed up as golden diagnosis criteria.Results Seventy-five benign tumors and 74 PTMC were confirmed by pathology.There were significant differences in echoes homogeneity between benign and malignant tumors in group 2(W =1 029.5,Z =-5.524,P =0.000) but no in group 1(W =933.0,Z =-1.738,P =0.082).And nonhomogeneous enhancement were showed in most PTMC in group 2.But most PTMC showed homogeneous enhancement in group 1.Conclusions Contrast-enhanced ultrasound is valuable in diagnosis of PTMC with the diameter size of 0.5-1.0 cm.

Objective To apply the binary Logistic regression model and evaluate the value of grey scale ultrasonography(US),ultrasond elastography(UE) and contrast-enhanced ultrasound(CEUS).Methods US,UE and CEUS were performed in 130 patients with 142 solid thyroid micronodules (the largest diameter less than 10 mm).Pathology was followed up as golden diagnosis criteria.A Logistic model on the basis of ultrasonographic features was obtained.A receiver operating characteristic(ROC) curve was used to assess the performance of Logistic model.Results Four ultrasonic indexes were finally entered into the Logistic regression model including microcalcification,acpect ratio,advanced CEUS mode and elasticity score.The percentage correction of prediction was 92.1％ (129/142),the area under the ROC curve was 0.944.Conclusions The multivariate analysis model of binary Logistic regression can describe and analyze the process of differential diagnosis of malignant and benign solid thyroid micronodules by ultrasonography,and select out the valuable indexes for differential diagnosis.

Objective:To understand the diagnostic value of tuberculosis (TB) pathogenic detection methods (TPDM) in pathological tissue for TB.Methods:A retrospective study was conducted with 190 pathological specimens from different tissues suspected with TB from Third People′s Hospital of Shenzhen during May 2016 and May 2019. Specimens were divided into four groups according to histomorphology: group one, necrotizing granulomatous inflammation (109 cases); group two, non-necrotic granulomatous inflammation (20 cases); group three, non-granulomatous inflammation (45 cases); group four, non-tuberculous lesions (16 cases). The positive rates of each TPDM among specimens from four groups were compared. The positive rates of all TPDM for specimens from group one were compared. Meanwhile, the influence of antituberculosis treatment course on the TPDM was analyzed. Chi-square test or Fisher′s exact test was used for statistical analysis.Results:The positive rates of Ziehl-Neelsen acid-fast staining among the four groups were 17.4%(19/109), 5.0%(1/20), 4.4%(2/45) and 0(0/16), respectively. The positive rates of Mycobacterium tuberculosis (MTB) complex culture were 32.0%(32/100), 4/19, 4.8%(2/42) and 0(0/16), respectively. The positive rates of Mycobacterium tuberculosis/rifampin resistance real-time quantitative nucleic acid amplification detection system (Xpert MTB/RIF) were 74.3%(81/109), 15.0%(3/20), 13.3%(6/45) and 0(0/16), respectively. The positive rates of fluorescent quantitative polymerase chain reaction (FQ-PCR) were 63.0%(58/92), 0(0/15), 2.6%(1/38) and 0(0/10), respectively. The positive rates of simultaneous amplification and testing (SAT) were 32.4%(24/74), 0(0/10), 0(0/15) and 0(0/10), respectively. The differences of each TPDM among four groups were all statistically significant (all P<0.05). The positive rate of Xpert MTB/RIF in group one specimens was significantly higher than those of acid-fast staining, MTB culture and SAT ( χ2=71.016, 37.162 and 35.679, respectively, all P<0.01), while the difference was not statistically significant when compared with FQ-PCR ( χ2=2.517, P=0.112). The positive rate of combined TPDM (85.3%(93/109)) was significantly higher than Xpert MTB/RIF(74.3%(81/109)) ( χ2=4.100, P=0.043). The positive rates of acid-fast staining group 1A (anti-tuberculosis treatment course was less than one month) and group 1B (anti-tuberculosis treatment course was longer than one month) were 14.3%(7/49) and 20.0% (12/60), respectively ( χ2=0.612, P=0.434); those of MTB culture were 48.9% (22/45) and 18.2% (10/55), respectively ( χ2=10.721, P=0.001); those of Xpert MTB/RIF were 69.4%(34/49) and 78.3%(47/60), respectively ( χ2=1.131, P=0.287); those of FQ-PCR were 55.0%(22/40) and 69.2%(36/52), respectively ( χ2=1.965, P=0.161); those of SAT were 43.3%(13/30) and 25.0%(11/44), respectively ( χ2=2.736, P=0.098). Conclusions:The results of TPDM correlate closely with the typical histomorphological features of tuberculosis. Xpert MTB/RIF possesses significantly higher sensitivity than any other single TPDM, and is not attenuated by early anti-tuberculosis treatment. Combined TPDM could significantly improve the sensitivity of TB pathogenic detection, which is suggested to be applied when the tissue specimen is sufficient.