Objective To construct Streptococcus mutans UA159 mutants with deletion of LuxS gene related to quorum-sensing pathway and evaluate the aciduricity of the mutants. Methods Using S. mutans UA159 as materials, the PCR fragments of the upstream and downstream regions of LuxS and erythromycin resistance(Eymr) gene of PJT10 were cloned into plasmid PUC19. The resulting constructs were integrated into the chromosome of S. mutans. LuxS gene deletion mutant was then constructed in S. mutans by means of allelic exchange and selected for resistance to erythromycin. The aciduric ability of the mutant under different pH was measured and S. mutans UA159 was used as control. Results The LuxS-deleted status of S. mutans mutants were confirmed by various PCR and DNA sequencing. The results showed that Eymr gene take the place of LuxS gene, while the mutant can not induce bioluminescenece. The LuxS mutant strain displayed a decreased growth ability with the decreasing pH values compared to those of the wild-type strain UA159. Conclusion A LuxS-negative mutants of S. mutans is constructed. The LuxS quorum sensing system is involved in the regulation of aciduricity of S. mutans UA159.

Objective To knock out the entire LuxS gene of Streptococcus mutans UA159 strain via homologous recombination and construct a LuxS-deleted mutant strain of S.mutans.Methods The erythromycin resistance gene(Eymr)was inserted between the two DNA fragments located in the upper and downstream of LuxS gene that had been amplified by PCR.Then the two DNA fragments along with the inserted Eymr were engineered into pUCl9 plasmid to construct the recombination plasmid pUCluxKO.Electrotransformation of S. mutans cells with pUCluxKO-mutant resulted in the isolation of erythromycin resistant S.mutans,transformants,which was then subjected to polymerase chain reaction,Vibrio harveyi BBl70 luminescence bioassay and sequencing analysis.Results Restriction endonuclease analysis showed that pUCluxKOmutant vector had been successfully recombined.The deletion of LuxS of S. mutans mutants was confirmed bv PCR with primers specific for the genes of LuxS and the erythromycin resistance.S.mutans mutant could not induce bioluminescence.indicating the mutant had been successfully recombined.The constructed Chinese S.mutans showed good stability after 20 generations of cultivation.Conclusion The S.mutans gene allelic exchange plasmid is constructed correctively and a LuxS-negative mutant of S.mutans has been constructed.which can be helpful for further study of the role of LuxS in the pathogenesis of S.mutans.

Wnt/β-catenin signaling pathway has a close relationship with cancer and is abnormally activated in many human cancers. Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related death worldwide, but the molecular mechanisms of HCC are still poorly understood. Current studies indicate that Wnt/β-catenin signaling pathway plays a key role in the development and progression of HCC. Validating the role and mechanism of Wnt/β-catenin signaling pathway in HCC will provide a theoretical basis for early diagnosis and treatment of HCC. In this review, we summarize the role of Wnt/β-catenin signaling pathway in HCC and the progress of current researches.
Carcinogenesis ; Carcinoma, Hepatocellular ; Humans ; Liver Neoplasms ; Wnt Proteins ; Wnt Signaling Pathway ; beta Catenin

Objective To use a simple bedside technique to verify the pathophysiological mechanism of pulmonary hypertension (PH) in different races. Method The Valsalva maneuver (VM) was performed in patients referred to a specialty PH clinic. The blood pressure response of patients to VM was in different fashions. The blood pressure (BP) was measured by using cuff and stethoscope. When the cuff was inflated to 15 mmHg above the systolic pressure, sound could be heard by auscultation during VM and when the cuff was deflated the sound disappeared over 3 heart beats which was considered as abnormal BP response, and less than 3 heart beats defined as normal BP response. The right heart catheterization in patients with PH as a part of the standard evaluation. Results This study included 84 patients with a mean age of (63 ± 16) years. Those with abnormal BP response to VM had higher pulmonary artery wedge pressure (PAWP) [(22.5±6.6) vs. (11.9±4.3) mmHg, P ＜0.0001] and lower pulmonary vascular resistance [(5.8 ± 4.0) vs. (8.1 ± 4.6 ) WU, P = 0.01]. Blood pressure response to VM did not correlate with mean pulmonary artery (PA) pressure [(46.2 ± 9.9) vs. (43.4 ±10.4) mmHg, P =0.20] or cardiac index (both 2.4 ± 0.6 L/min/m2). The abnormal BP response to VM had high sensitivity (89.4%), specificity (86.1%) and accuracy (86.9%) for determining PAWP＞ 15 mmHg.Conclusions BP response to Valsalva maneuver provides important information about left heart filling pressures in patients with PH.

Objective To study the impact of different insulin levels on the conversion from impaired glucose tolerance (IGT) to type 2 diabetes mellitus (T2DM),through analysis of different glycometabolism condition among quinquagenarian population.Methods Subjects enrolled were Beijing habitants who received annual physical examination [ including oral glucose tolerance test (OGTI) ] in the Chinese PLA General Hospital from 2005-2007.According to the OGTT results,the subjects were divided into three groups,including normal glucose tolerance-non-hyperinsulinemia group (NGT-NHIns),IGT-hyperinsulinemia group (IGT-Hins) and IGT-non-hyperinsulinemia group (IGT-NHINS).The prognosis between the year 2009 and 2010 of the three groups was observed.Hyperinsulinemia was diagnosed with fasting serum insulin ≥ 15 mU/L and/or 2-hour serum insulin ≥ 80 mU/L after glucose loading.Results The rate of case number of conversion to T2DM in IGT-NHIns group (42/133) was higher than that in IGT-Hins group (24/154) or NGT-NHIns group (12/126).The HOMA insulin resistance index (HOMAIR) of individuals with IGT-NHIns was lower than that of IGT-Hins [ 0.96 (0.40,3.53 ) vs 2.04 (0.59,23.20),P ＜ 0.05 ],while whole body insulin sensitivity index (WBISI) was higher than that of IGT-Hins [ 7.48 (3.20,31.35 ) vs 3.28 ( 0.86,7.67 ),P ＜ 0.05 ].Modified β-cell function index ( MBCI ) and insulin secretion index (ISI) in IGT-NHIns was poorer than that of IGT-Hins respectively [ 2.57 (0.58,10.98) vs5.17(1.04,65.09); 7.66 (0.99,28.40) vs 17.56 (4.18,96.46),allPvalues ＜0.01].Conclusions The risk of IGT-NHIns progressing into T2DM is higher than that of IGT-Hins. For the prevention of T2DM,individuals with IGT-NHIns should be paid more attention than keeping an eye on IGT-Hins patients.Early control of risk factors could protect β cell function and prevent the progression to T2DM.

BACKGROUNDTo evaluate the significance of flow cytometry (FCM) in the analysis of multi-drug resistance of doxorubicin.

METHODSThe level of doxorubicin or Rh-123 in S-180R and BGC-823/DOX, which were two cell lines with different drug resistance, was measured by FCM comparatively and continuously.

RESULTSThe total fluorescence profile peaks of S-180R, a high resistant cell line, were predominantly different from those of S-180, the parent cell line, by the FCM analysis. The subtle fluorescence profile differences between BGC-823/DOX (a low resistant cell line) and the parent cell line were quantitatively measured on the FCM map. The changes of each resistant cell fluorescence from the S 180R cells could be displayed by continuous tests, the more near the fluorescence level of each cell was, the more the fluorescence pike of whole cells centralized.

CONCLUSIONSFCM is a sensitive, accurate and quantitative test in the analysis of doxorubicin drug resistance.

Objective:To analyze the implementation effects of a medical laboratory talent training program based on local colleges and universities' applied talent-oriented cultivation principal as well as students' interests and industry needs.Methods:Based on the design principals of clarifying the professional orientation, meeting the national standard, reconstructing the curriculum system, introducing the spirit of innovation and entrepreneurship, and multi-dimensional collaborative education, as well as the reverse design path of the outcome-based education concept, we have built a medical laboratory applied talent training system focusing on humanity education, solid foundation, broad employment, and good competency and in accordance with the "three complete education" strategy, along with measures including creating an applied teaching atmosphere, developing an applied curriculum teaching model, providing vocational guidance and improving vocational identity, and promoting education via evaluation. The system was applied to the training and practice of students of grades 2021 and 2022 majoring in medical laboratory technology. SPSS20.0 software was used for statistical analysis.Results:With the concept of application-oriented talent training and the "four-in-one" practical teaching model, students' skills were improved, and the training path was broadened. Compared with those trained with the original program (grades 2019-2020), the graduates trained with the new program (grades 2021-2022) showed a significantly decreased employment rate in medical laboratory jobs in medical institutions from 71.25% to 42.86% ( χ2=12.36, P<0.001), a significantly increased employment rate in in-vitro diagnostics industry from 3.75% to 17.14% ( χ2=7.44, P<0.05), and a significantly increased rate of applying for postgraduate education from 17.05% to 32.86% ( χ2=4.74, P<0.05). Conclusions:The medical laboratory talent training program based on the talent training principal of local colleges and universities combined with students' interests and industry needs can help improve the quality of talent training and broaden the employment path of graduates.

Objective To evaluate the accuracy of different noninvasive methods for the diagnosis of nonalcoholic steatohepatitis(NASH) and hepatic fibrosis in patients with non-alcoholic fatty liver disease (NAFLD) combined with type 2 diabetes mellitus(T2DM). Method A prospective comparative study was performed for 91 patients with T2DM and NAFLD, which were diagnosed by glucose tolerance test and liver biopsy. The height and body mass of the patient were measured, and the body mass index(BMI) was calculated. The fasting venous blood of the patient was collected, and then the blood routine, liver function and ferritin were measured. NPS, neutrophil lymphocyte ratio(NLR), BARD score, FIB-4 index, APRI, and NAFLD fibrosis score(NFS) were calculated. All patients underwent transient elastography (Fibrotouch) to evaluate the degree of liver stiffness measurement (LSM) and controlled attenuation parameter. All the liver biopsy specimens were categorized by SAF as the gold standard for evaluating NASH and liver fibrosis NASH. Correlation analysis was applied to compare the correlation between the noninvasive methods and SAF. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) were used to assess the diagnostic value of the noninvasive methods for NASH and liver fibrosis NASH. Results In T2DM combine with NAFLD patients, NPS, LSM, NFS, APRI, FIB4 and BMI scores were positively correlated with SAF (r value was 0.509, 0.508, 0.252, 0.396, 0.313 and 0.213, respectively; P value was <0.001, <0.001, 0.016,<0.001, 0.003 and 0.043, respectively). LSM, NPS, NFS and FIB4 scores were positively correlated with liver fibrosis (r value was 0.535, 0.337, 0.315 and 0.315, respectively; P value was <0.001, 0.001, 0.002, 0.002, respectively). The ROC curve shows that the area under the curve of NPS, LSM, APRI, FIB4 and BMI for diagnosing NASH was 0.838, 0.760, 0.734, 0.623 and 0.682, respectively, and P value was 0.000, 0.000, 0.000, 0.044 and 0.003, respectively. For the diagnosis of fibrotic NASH, that value of LSM, NFS, FIB4 and NPS was 0.795, 0.765, 0.686 and 0.623, respectively, and P value was 0.000, 0.001, 0.020 and 0.123, respectively. Conclusions NPS, LSM and APRI have good clinical diagnostic value for NASH. LSM and NFS have good diagnostic value for fibrotic NASH.

Objective: To investigate the effect of dietary control combined with different exercise modes on plasma vaspin, irisin, and metabolic parameters in patients with non-alcoholic fatty liver disease (NAFLD) through a randomized open parallel-controlled study. Methods: The patients aged 30-65 years who visited Tianjin Third Central Hospital from January 2013 to December 2014 and were diagnosed with NAFLD by liver ultrasound and fat content determination were screening, and 474 patients were enrolled in this randomized controlled trial and divided into aerobic exercise group, resistance exercise group, and control group. All patients received dietary intervention. The three groups were compared in terms of biochemical parameters, fat content, NFS score, energy metabolic parameters, body composition index, and levels of vaspin and irisin at baseline and after 6 months of intervention. SPSS 19.0 was used for statistical analysis. The t-test, the Mann-Whitney U test, the chi-square test, and an analysis of variance were used for comparison between groups. The multiple imputation method was used for missing data, and the results were included in the intention-to-treat analysis. Results: There were no significant differences in age, sex, anthropometrical parameters, and biochemical parameters between the three groups at baseline. Compared with dietary control alone, aerobic exercise and resistance exercise helped to achieve significant reductions in waist circumference, diastolic pressure, percentage of body fat, volatile fatty acid, fasting blood glucose, homeostasis model assessment of insulin resistance, triglyceride, low-density lipoprotein cholesterol, free fatty acid, uric acid, alanine aminotransferase, and liver fat content after 6 months of intervention (P < 0.05). The aerobic exercise group had a significant increase in non-protein respiratory quotient and significant reductions in body mass index and aspartate aminotransferase after intervention, as well as a significant increase in resting energy expenditure and significant reductions in abdominal fat ratio and total cholesterol after 6 months of resistance exercise (P < 0.05). The aerobic exercise group and the resistance exercise group had a significant reduction in vaspin and a significant increase in irisin after intervention (P < 0.05), and the resistance exercise group had significantly greater changes in these two adipokines than the aerobic exercise group (P < 0.05). Conclusion Exercise therapy is an effective method for the treatment of metabolism-associated diseases, and a combination of resistance and aerobic exercises is more reasonable and effective in clinical practice. As a relatively safe exercise mode, resistance exercise can also effectively improve the metabolic state of NAFLD patients.