R04, a Gram-positive bacterium, which can use biphenyl as the sole carbon source, was isolated from soil contaminated with oil in northern China. The bacterium has high biphenyl degradation efficiency and also can degrade polychlorinated biphenyl congeners, Aroclor1221 and Aroclor 1242. The bacterium was identified as Rhodococcus pyridinovorans by the method of 16S rDNA gene sequencing (accession No. AY072745).

The directed molecular evolution of enzyme in vitro can not only improve the efficiency of evolution, but also evolve enzyme according to the investigator's desire. This review summed up the feasible methods of this novel technique.

Objective To investigate the role of microsatellite instability(MSI) in the carcinogenesis and development of gastric cancer (GC). Methods MSI was examined in 36 gastric cancer specimens obtained endoscopically and during surgery and in 30 intestinal metaplasia specimens using PCR SSCP methods. Results MSI was detected in 15 of 36 GC and 9 of 30 intestinal metaplasia specimens at one or more loci. MSI was positive in all three cases of early GC. The incidence of MSI in well differenciated GC was significantly higher than that in poorly differentiated GC (66.7% vs 26.3%, P

Bone Marrow Cells ; Cell Line ; Cell Proliferation ; Humans ; Mesenchymal Stromal Cells ; cytology ; T-Lymphocytes ; cytology ; T-Lymphocytes, Regulatory ; cytology

Contraindications ; Humans ; Laryngeal Neoplasms ; classification ; pathology ; surgery ; Laryngectomy ; methods ; Neoplasm Staging

BACKGROUND:The treatment of infected nonunion is a difficult problem in orthopedic trauma, which needs to completely eliminate foci of osteomyelitis to control infection, repair soft tissue defect and close the wound, repairs bone defects to promote healing and protect limb function as much as possible. Autogenous micromorselized bone can be easily obtained and recombinant human bone morphogenetic protein-2 has variety of sources. Their mixed grafting mode is safe and reliable in repairing of bone defects, which are suitable for repair of infected nonunion. ＜br> OBJECTIVE:To study the operating method and clinical results of repairing infected nonunion using autogenous micromorselized bone grafting mixed with bone morphogenetic protein-2. ＜br> METHODS:Twenty-three cases underwent infected nonunion repair with autogenous micromorselized bone (l ium, long bone metaphyseal cancellous bone) mixed with bone morphogenetic protein-2, including 7 cases of femoral bone defect caused by osteomyelitis after debridement and external fixation and 16 cases of tibial bone infected nonunion. Eleven of 23 cases continued to use the external fixation because of scar contraction or poor conditions of soft tissue, and the other 12 cases switched to use internal fixation. X-tray was taken to evaluate the bone healing at the 1st, 3rd, 6th and 12th months after operation. The function of the affected extremity was assessed by Johner-Wruhs grade. ＜br> RESULTS AND CONCLUSION:Al of the cases were averagely fol owed up for 13.4 months. The bone defects and bone fracture healed in al cases without infection, and the wounds were al sealed. The excellent and good rate according to Johner-Wruhs grade was 95%. These findings indicate that the bone grafting mode of autogenous micromorselized bone mixed with bone morphogenetic protein-2 is characterized as variety of sources, high safety and reliable osteogenic ability in repair of bone defects.

Objective To investigate the clinical significance of the level of regulatory T(Treg)cells and indoleamine 2,3-dioxygenase(IDO)in HBV-induced hepatocellar cancinoma.Methods 51 cases of HBV-DNA positive primary liver cancer(HCC),44 cases of chronic hepatitis B(CHB),29 cases of cirrhosis and 28 cases of healthy volunteers(control group)were used RT-PCR and flow cytometry to detect the expression of Treg cells and IDO in peripheral blood of each group.Results The expression of IDO mRNA from high to low were HCC group,CHB group,liver cirrhosis group and control group.The control group and the liver cirrho-sis group were lower than the other 2 groups(P<0.01),and the difference between the other groups was sta-tistically significant(P<0.05).Treg counts from high to low were HCC group,cirrhosis group,CHB group and control group.HCC group was significantly higher than that of control group(P<0.05),except for CHB group,Treg cells in each group were statistically significant compared with control group(P<0.05).The cor-relation analysis of expression of IDO mRNA and Treg:r=0.912,P=0.000,indicating that the expression of IDO in peripheral blood was positively correlated with the Treg cells.Conclusion IDO is over expressed in HCC with the high Treg cell level.Treg cells and IDO may associated with hepatocellular carcinoma immune escape mechanisms.

Objective To analyze the antimicrobial susceptibility of Mycoplasma isolates for rational antimicrobial therapy. Methods BioM?rieux IST kit was used for identification and susceptibility testing of Mycoplasma strains.Results Mycoplasma was positive in 49.5% of the specimens tested.Of the Mycoplasma detected,Ureaplasma urealyticum(Uu)alone accounted for 74.7%,Mycoplasma huminis(Mh)alone accounted for 18.1%,and Uu+Mh was identified in 7.2% of the patients.The results of antimicrobial susceptibility testing showed that the Mycoplasma isolates were most susceptible to doxycycline (98.1%).Ciprofloxacin was the least active (17.3%).Conclusions Doxyeycline,josamycin,and clarithromycin can be used in the treatment of urinary tract infections caused by Mycoplasma.

Objective:To investigate the progression pattern of acquired resistance to osimertinib and the treatment method as well as the therapeutic effect of salvage therapy in advanced lung cancer patients with epidermal growth factor receptor (EGFR) sensitive mutation or T790M mutation after the treatment of tyrosine-kinase inhibitor (TKI).Methods:The data of 145 patients with advanced lung cancer treated with osimertinib in Jiangsu Cancer Hospital between April 2017 (the approval time of osimertinib in China) and May 2019 were collected. At the last follow-up (December 2019), a total of 87 (60.0%) patients had acquired resistance to osimertinib, 61 (70.1%) of whom received salvage treatment; for patients with dramatic progression after resistance, chemotherapy was mainly given in the salvage therapy; for patients with gradual or local progression after resistance, the continuing targeted drug therapy and the local therapy were given. Imaging evaluation and Kaplan-Meier method were used to analyze the progression pattern of acquired resistance to osimertinib and the survival status, and to compare the salvage treatment results among subgroups.Results:The median follow-up time of 61 patients receiving salvage therapy was 11 months (4-32 months), among which 58 (95.1%) patients again had resistance to osimertinib, and 24 (39.3%) patients died of lung cancer. The median progression-free survival (PFS) time and overall survival (OS) time for the whole cohort was 2.5 months (95% CI 2.1-3.0 months) and 19.0 months (95% CI 13.7-26.3 months), respectively. The 1-year and 2-year OS rate was 72.1% and 41.7%, respectively. Among 61 patients receiving salvage therapy, 8 (13.1%) , 30 (49.2%) and 23 (37.7%) cases had dramatic progression, gradual progression and local progression, respectively; when given timely and proper salvage treatment, there were no statistically differences in PFS and OS of the patients in the above three subgroups (all P>0.05). There were no statistically differences in PFS and OS between patients receiving local therapy (24 cases) and patients not receiving local therapy (37 cases) after the progression occurred (all P>0.05). Among 58 patients with resistance to osimertinib again after the salvage therapy, 6 patients with gradual or local progression had more than 6-mouth PFS after the salvage therapy. Conclusions:Dramatic, gradual and local progression are the main patterns in patients with acquired resistance to osimertinib. The therapeutic efficacy of salvage therapy still shows some disappointing results.

Objective To evaluate diagnostic value of diffusion tensor imaging(DTI)in ringlike- enhanced lesions.Methods Nine abscesses,12 glioblastomas,10 metastases confirmed clinically or pathologically underwent conventional MRI and DTI.Average diffusion coefficient(ADC)value,fractional anisotropy(FA)value and maps were calculated in the central portion and peripheral edema of the lesions. Results On DTI,the abscesses displayed as hyperintense signal with hypointense or isointense signal of edema;but glioblastomas and metastases all showed as hypointense signal with isointense or hypointense signal of edema.On ADC map,the abscesses showed as hypointense signal,the mean ADC value was (0.66?0.07)x10~(-3)mm~2/s,The mean ADC value were(2.50?0.11)x10~(-3)mm~2/s and(2.37?0.52)x10~(-3)mm~2/s for the glioblastomas and metastases,respectively,all demonstrated as hyperintense signal with slightly hyperintense signal of edema.The difference between abscess and necrotic tumors was statistically significant(F=108.80,P