OBJECTIVEThis study aims to evaluate the effect of ptxA and ptxB genes, which are important genes in the L-ascorbate phosphotransferase system (PTS) of Streptococcus mutans (S. mutans).

METHODSThe ptxA-, ptxB-, and ptxAB-double deficient mutant as well as ptxAB-complemented strain were constructed. Quantitative real-time polymerase chain reaction analysis was performed to evaluate the expression of the target genes of wild-type S. mutans when L-ascorbate was used as the sole carbohydrate source. The OD₆₀₀ values of the wild type, deficient, and complemented strains were continuously monitored, and their growth curves were constructed to compare growth capacity.

RESULTSPolymerase chain reaction and sequencing analyses suggested that deficient and complemented strains were successfully constructed. The expression levelsof ptxA and ptxB significantly increased (P < 0.01) when L-ascorbate was used as the sole carbohydrate source. The growth capacity of the deficient mutants decreased compared with that of the wild-type strain. However, the wild-type phenotype could be restored in the complemented strain.

CONCLUSIONptxA and ptxB genes are associated with L-ascorbate metabolism of S. mutans. The construction of deficient strains and complemented strain lay a foundation for further mechanism study on L-ascorbate metabolism in S. mutans.

Bacterial Proteins ; genetics ; Genes, Bacterial ; Phosphotransferases ; metabolism ; Real-Time Polymerase Chain Reaction ; Streptococcus mutans ; physiology ; Transcription Factors ; genetics

OBJECTIVE: By studying the MRI apperances of postcricoid area invaded by laryngeal carcinoma, to identify the characteristic appearances of the invaded postcricoid area and to provide information on the early detection of the lesions. METHOD: Eighteen cases of MRI images of postcricoid area invaded by laryngeal carcinoma were included in this study. To find out the characteristic manifestation of the lesions, the destructions of surrounding structures and layers, and the invaded extent were observed. RESULT: In 18 cases the invaded lesions of postcricoid area include the mucous layer, submucous fat layer and the mucous layer of anterior wall. In 14 cases the invaded lesions of postcricoid area include the mucous layer, submucous fat layer and the mucous layer of the posterior wall. The soft tissue mass was found in 15 cases, and disappeared hypopharynx cavity in 16 cases. In 14 cases, the full-thickness of both anterior and posterior walls were invaded, accompanied with soft tissue mass and disappeared hypopharynx cavity. CONCLUSION The postcricoid area invaded by laryngeal carcinoma usually shows the destruction of normal structures, signal change in MRI and soft tissue mass. Being familiar with the imaging of the invaded postcricoid area is extremely important to early detect laryngeal carcinomas invading postcricoid area.
Cricoid Cartilage ; pathology ; Humans ; Hypopharyngeal Neoplasms ; diagnosis ; Hypopharynx ; pathology ; Laryngeal Neoplasms ; diagnosis ; Larynx ; pathology ; Magnetic Resonance Imaging

Objective: To learn the technical efficiency and influencing factors of hospital beds in China′s hospitals from 2010 to 2016. Methods: The two-stage Network DEA-Tobit model was used to analyze the technical efficiency and influencing factors of hospital beds at all levels in China. Results: There was a big difference in the utilization status of hospital beds at all levels. The bed burden of tertiary hospitals was heavier, and their average bed occupancy rate was 102%, while the potential of primary and secondary hospital beds was relatively large. The average technical efficiency of the hospitals in the primary, secondary and tertiary hospitals was 0.99, 0.37 and 0.82, respectively. Over-investment of resources for beds in hospitals at all levels was found with insufficient output, and the utilization of bed resources in primary and secondary hospitals was seriously insufficient. The nurse-bed ratio, per capita medical expenses of hospitalized patients, per-bed income and financial subsidy to the technical efficiency of the hospital bed were statistically significant. The correlation coefficient between the guard bed ratio and the technical efficiency of the hospital bed was 3.106 409. Conclusions It is necessary to further implement the hierarchical medical system and clarify the functional positioning of hospitals at all levels. It is recommended to control the scale of investment and improve the utilization efficiency of existing bed resources, and it is also imperative to improve the medical technology level and diagnosis rate of hospitals at all levels, and promote the maximization of bed utilization efficiency.

Objective.So far,it has not been established a satisfactory method for early diagnosis and studying on epidemiology for leprosy,we want to develop a molecular biological method for solving this point.Materials and methods.Based on the M.leprae gene coding groEL,65kD and 16S rRNA,three polymerase chain reactions were developed by using plikaytis',Woods' and Pattyn's procedures.It was optimized that the experimental parameters for each PCR,and a comparative study on practivity among three PCRs was also conducted for practical purpose.Results and conclusion.For detecting infection with M.leprae,all of PCRs established by us were highly sensitive and specific,but for practicl purpose,the woods'PCR optimized by us ought to be chosen firstly.

Objective:To explore the possible related factors of Beh?et's disease complicated with tendinitis, in order to better understand the etiology and development mechanism so to guide clinical diagnosis and treatment.Methods:The clinical data of patients with Beh?et's disease complicated with tendonitis treated at Department of Rheumatology and Immunology of Lanzhou University Second Hospital from October 2018 to September 2019 were retrospectively reviewed and related literature were reviewed.Results:Two patients were diagnosed as Beh?et's disease. Foot pain occurred during the treatment. Ultrasound showed tendonitis, and the corresponding treatment relieved the symptoms.Conclusion:Tendons may be involved and presents as a chronic change in patients with Beh?et's disease. In patients with rheumatic diseases, attention should be paid to the correlation between the disease and tendonitis. Aggressive treatment can prevent adverse consequences.

Objective: To understand the current situation of mental health education in primary and secondary schools in Beijing, so as to provide the data support and policy suggestions for mental health work in Beijing. Methods: From April to May 2024, a multi stage random sampling method was used to select 399 primary and secondary schools in Beijing to conduct a questionnaire survey. Chi square test was used to compare the differences resource allocation of mental health education, current status of mental health education by regions and educational stages. Results: There were significant differences in reporting rates for the allocation of professional and part time psychological teachers in different regions and educational stages (professional: χ 2=17.86, 20.74 , part time: χ 2=13.56, 25.63, P <0.05). There was significant differences the implementation of mental health education courses for students in different educational stages ( χ 2=12.83, P <0.05). There was significant differences the implementation of mental health education training for staff in different regions ( χ 2=17.79, P <0.05). Professional psychology teachers were well equipped in urban schools (84.13%) and 9 year or 12 year schools (85.33%),and part time psychology teachers were well equipped in suburban schools (68.49%) and primary schools (71.35%). Schools in the outer suburbs (96.88%) had the best implementation of mental health education training for staff, and the 9 year or 12 year schools (100.00%) had the best implementation of mental health education courses for students. Totally 93.98% of schools carried out mental health education activities, 90.23% of schools established mental health consultation rooms, and 88.97% of schools integrated mental health education into other courses. Conclusions The development of mental health education in primary and secondary schools in Beijing is good. It is suggested that the quality of mental health education in primary and secondary schools in Beijing should be improved by implementing the requirements of psychological teacher allocation, the coordination among family, school and community, and paying attention to teachers mental health level.

OBJECTIVETo investigate the feasibility and short-term efficacy of laparoscopic resection of primary localized gastric gastrointestinal stromal tumors (GIST) by comparing with open surgery.

METHODSClinicopathological data of 167 gastric GIST patients undergoing operation in Zhongshan Hospital from June 2008 to December 2013 were retrospectively analyzed, among whom 55 received laparoscopic surgery and 112 underwent open surgery for primary local gastric GIST. Efficacy of different size and different location of GIST was compared between laparoscopic and open groups.

RESULTSThere was no conversion to open surgery in laparoscopy group. Compared with open surgery, laparoscopic resection for gastric GIST smaller than 5 cm or located at anterior wall, greater curvature, lesser curvature, was associated with similar operation time(P>0.05), but less blood loss, shorter post-hospital stay or flatus time(all P<0.05). The operative outcomes were similar between laparoscopic and open resection for gastric GIST bigger than or equal to 5 cm or located at posterior wall(all P>0.05), except the longer operation time in laparoscopy group(P<0.05). The incidence of postoperative complication did not differ between two groups. Laparoscopic group had 2 patients with gastroparesis and open group had 2 gastroparesis, 2 pulmonary infection, and 1 poor wound healing(all P>0.05), which all recovered after conservative treatment. During 7 to 84 months(median 35) of follow-up, no recurrence or hepatic metastasis was found in laparoscopy group, and 3 hepatic metastases in open group. There was no significant difference of recurrence-free survival between two groups(P>0.05).

CONCLUSIONLaparoscopic resection for gastric GIST is safe and effective in selected patients, especially for those with tumors smaller than 5 cm, or located at anterior wall, greater curvature, lesser curvature, whose short-term outcomes are better than open resection.

OBJECTIVETo explore the clinicopathological characteristics, efficacy, and prognostic factors for patients with duodenum gastrointestinal stromal tumor(GIST).

METHODSClinicopathological and follow-up data of 80 patients with duodenum GIST in the Zhongshan Hospital from January 2000 to December 2013 were analyzed retrospectively.

RESULTSThere were 38 male and 42 female patients with a median age of 54 years. The major symptoms were upper alimentary tract hemorrhage and abdominal pain. Thirty-nine patients received local tumor excision, 18 patients underwent segmental duodenectomy, 23 patients were subjected to pancreaticoduodenectomy, all these operations were R0 resection. Thirty patients received imatinib treatment after operation, and 11 among them had metastasis relapse. Recurrence-free survival rates of 1-, 3-, and 5-years were 96.2%, 90.6%and 78.6% retrospectively. Overall survival rates of 1-, 3-, and 5-years were 100%, 98.3% and 96.1%. Multivariate Cox analysis showed tumor size >5 cm, mitotic count >5 mitosis/50 HPF and intermediate/high NIH risk classification were associated with an increased risk of recurrence. The significant difference was not detected between the limited resection group and pancreaticoduodenectomy group in OS and RFS.

CONCLUSIONSSurgery is still the main treatment for duodenum GIST. The surgical program is mainly determined by the location and size of tumor. Imatinib therapy should be used if necessary.

Abdominal Pain ; Benzamides ; Duodenal Neoplasms ; Female ; Gastrointestinal Hemorrhage ; Gastrointestinal Stromal Tumors ; Humans ; Imatinib Mesylate ; Male ; Middle Aged ; Multivariate Analysis ; Neoplasm Recurrence, Local ; Pancreaticoduodenectomy ; Piperazines ; Prognosis ; Pyrimidines ; Retrospective Studies ; Survival Rate

OBJECTIVETo investigate the clinicopathological features of small gastrointestinal stromal tumors(GISTs) and to evaluate the efficacy of endoscopic therapy for GISTs.

METHODSClinicopathological and follow-up data of 418 patients with GISTs undergoing endoscopic therapy in the Zhongshan Hospital between January 2009 and July 2014 were analyzed retrospectively. All the cases were evaluated by the NIH risk classification and AIFP classification, and were grouped according to the tumor size and location. Nuclear atypia and mitotic count were used to evaluate the biological behavior of small GIST. Efficacy of endoscopic therapy was analyzed with follow-up data.

RESULTSOut of 418 patients, GISTs located in the esophagus was 14(3.3%), in the stomach 389(93.1%), in the duodenum 5(1.2%), in the rectum 10(2.4%). A total of 412(98.6%) patients were mainly spindle cells, and mitosis was not found in 320(76.5%) patients. In 389 small stomach GIST, 245(58.6%) were in fundic region. Cases were divided into four groups according to the size and the result revealed the bigger the size, the more the mitotic count. Nuclear atypia in the 1.5-1.9 cm group was significantly higher compared to other groups. Cases were divided into four groups according to the location and the result revealed the mitotic count was not associated to the location. While the nuclear atypia of stomach GIST was significantly higher than that of esophageal GIST and the nuclear atypia of rectum GIST was significantly higher than that of other positions. The median follow-up was 32(4-69) months. One case(gastric fundus GIST, >1.5 cm) presented local recurrence 23 months after operation and underwent endoscopic resection again. No recurrence or metastasis was found in other patients.

CONCLUSIONSEndoscopic resection technique is effective for small GISTs patients. The small GISTs with 0.4 cm diameter or less are often benign and should be followed up for long time. The small GISTs with 0.5 cm diameter or more possess the risk of malignancy, then surgical resection should be performed. Rectum small GISTs (except for 0.4 cm diameter or less) have worse biological behavior and should be removed.

Gastrointestinal Neoplasms ; Gastrointestinal Stromal Tumors ; Humans ; Neoplasm Recurrence, Local ; Retrospective Studies

Objective To investigate the diagnostic value of PSV/PSVpop,a new parameter detected by color Doppler ultrasonography,for patients with severe s tenosis (70 ％-99 ％)in superficial femoral artery (SFA).Methods One hundred and eighty-five cases (234 limbs) with SFA stenosis detected by CDU and confirmed by DSA were included in this study.Peak systolic velocity of intra stenotic(PSV),proximal stenotic (PSVpro),and popliteal artery (PSVpop) were measured and recorded respectively.The ratio of PSV/PSVpro,PSV/PSVpop were calculated.Using DSA as the gold standard,the cut off values for the diagnosis of severe stenosis were determined with receiver operating characteristics (ROC) analysis.The efficacy of the above parameters were compared.Results The new parameter PSV/PSVpop≥4 had 96.3％ of sensitivity,91.6％ of specificity,94.4％ of accuracy,95.7％ of positive predictive value,and 91.4％ of negative predictive value and 0.978 of area under the ROC curve(AUC) could define 70％-99％ stenosis of SFA.The AUC of PSV/PSVpop was higher than those of the traditional parameters PSV(0.922) and PSV/ PSVpro(0.920),the difference was statistically significant (P ＜0.01).The AUC of combined parameter PSV/PSVpop + PSV surpassed conventional combined parameter PSV/PSVpro + PSV (0.978 ∶ 0.940,P ＜ 0.05),but had no statistically significant difference with single parameter of PSV/PSVpop (0.978 ∶ 0.978,P ＞ 0.05).Conclusions The diagnostic efficacy of PSV/PSVpop is superior to traditional hemodynamic parameters in the diagnosis of SFA severe stenosis.