A thermostable DNA ligase gene was identified, and the biochemical and enzymatic properties of the ligase were characterized from JP2 strain which was enriched from geothermally active sites in Papua New Guinea. The nucleotide and amino acid sequences showed much high identities compared with that of archeabacterium species Sulfolobus solfataricus and Sulfolobus shibatae,especially in the six conserved motif sequences, which are known to be closely related to the key function of ligase. Recombinant JP2 ligase showed high activity in nick-joining reaction. It was the most active when Mn2+ present as divalent metal cofactor rather than Mg2+ and Ca2+ etc.. Assay of thermostability over a range of temperatures showed that at 50～80℃ the enzyme displayed relative high activity. Further thermostability experiment indicated that the activity of JP2 ligase could last for a long time at 80℃ and 85℃,however, at 90℃ and 95℃, it became unstable quickly. An investigation on the acquired thermotolerance of recombinant JP2 ligase was done by applying a chaperonin known as TF55 in thermophile on JP2 ligase reaction. Result showed that TF55 could not help in improving thermostability of ligase at 85℃. The possible reason might be that at 85℃ in vitro, the chaperonin itself was denatured.

BACKGROUND: Drug use is the most significant risk factor for viral hepatitis B and C infection. Female drug users present different drug-using characteristics from the other sex. And what about the influence of these characteristics on hepatitis B and C virus(HBV and HCV) double infection?OBJECTIVE:To explore the relationship of characteristics of drug using in female drug users on the incidence of HBV and HCV double infection.DESIGN: It is a cross section investigation of female drug users in January 2002.SETTING: A laboratory separtment, an epidemiological department in a university and a drug dependency treatment unit.PARTICIPANTS: A total of 320 female drug users who were in Baimalongdrug dependency treatment unit in Zhuzhou city were recruited in this study.METHODS: The drug-using characteristics were investigated through a questionnaire and the surface antigen of HBV(HBsAg) and antibody against HCV(anti-HCV)in serum were checked with ELISA.MAIN OUTCOME MEASURES: Relationship between HBV and HCV infection and injection of drug, injecting career and abstaining history.RESULTS:The incidence of HBV and HCV double infection in the 320 female drug users was 9. 37%. All of those with double infection were injection drug users, which was different from non-injection drug users(x2 = 6. 276,P ＜ 0. 05 ) . Longer career of drug-using meant higher possibility of double infection. The incidence of double infection (10. 3% ) in those of 5 - 10 years of drug-using career was higher than that (4.5%) of 1 - 5 years of drug-using career (x2 = 8. 344, P ＜ 0.05) . And that in those experienced more than 4times of abstaining was also higher than that less than in those experienced 3times (x2 =9. 418, P ＜ 0. 05) . Long career of drug using and repeated abstention abstaining were factors that leaded to HBV and HCV double infection (OR = 1. 923, 1. 597, 95% CI = 0. 964 - 3. 838, 0. 962 -2. 652).CONCLUSION: Injection drug use is the predominant factor that causes double infection of HBV and HCV and long career of drug using and rising in the number of times of abstaining also increase the double infection.

BACKGRUND:The high prevalence of hepatitis B virus(HBV) is related with the sexual characteristics in drug abusers.How about the relationship between prevalence of HBV/hepatitis C virus(HCV) co infection and the sexual characteristics in drug abusers? OBJECTIVE:To investigate the relationship between sexual characteristics and HBV/HCV co infection in drug abusers. DESIGN:A cross sectional survey taking the drug abuser as the subjects. SETTING:A department of clinical laboratory of a municipal hospital,an epidemiological department of the college of public health of a university,a professional drug abuser treatment center. PARTICIPANTS:Totally 452 male and 320 female drug abusers were randomly selected from the Changsha Xinkaipu Drug Abusers Treatment Center and Zhuzhou Baimalong Female Drug Abusers Treatment Center as the subjects from 1st to 31st January 2001. INTERVENTIONS:A self designed questionnaire was used to investigate the sexual characteristics of drug abusers.HBV surface antigen and HCV antibody were detected in the serums of the participants with ELISA. MAIN OUTCOME MEASURES:The relationship between HBV/HCV co infection and the sexual behavior, numbers of sexual partners,and the usage of condom in drug abusers. RESULTS:The total prevalence of HBV/HCV co infection in drug abusers was 21.24% ; the prevalence of HBV/HCV co infection in male drug abusers was 29.6% ),which was significantly higher than that in females(9.4% )(χ 2=46.016,P< 0.01).There was no significant difference in the prevalence of HBV/HCV co infection between male and female drug abuser whether they had or had not sexual behaviors(χ 2=3.775,P >0.05).The prevalence of HBV/HCV co infection was in an ascending tendency with the increase of sexual partner(χ 2=9.846,P< 0.05).The using frequency of condom was significantly higher in females than in males(U=14.80,P< 0.01). CONCLUSION:There is no correlation between sexual experience and prevalence of HBV/HCV co infection;male drug abusers have higher prevalence of co infection than females;the number of sexual partners is correlated with the prevalence of HBV/HCV co infection,the more sexual partners,the higher prevalence is.The protective effect of condom is greater in female drug abusers than in males.

Objective To compare the results of three dose verification solutions of esophageal carcinoma IMRT plans. Methods Seven esophageal carcinoma cases were planned with Pinnacle 8.0 h.The MATRIXX and Delta4 were chosen as the two-dimensional dosimetry and three-dimensional dosimetry.IMRT plans and Delta4 phantom plans were also recalculated by Monte Carlo. Gamma values were evaluated for MATRIXX and Delta4 with 3 mm/3% gamma criteria. For the comparison of Pinnacle, Delta4 and Monte gamma maps, the dose distribution in central plane, dose profiles and dose-volume histograms were used to evaluate the agreement. Results The gamma maps comparison show that with 3 mm/3% gamma criteria an over 98% pass ratio was obtained by MATRIXX measurement. A 94. 4% gamma pass ratio whicl.contains 4 fields gamma pass ratio lower than 90%, was obtained by Delta4 measurement. A 97.6% and 99. 8% gamma pass ratio was obtained between the Delta4 measurement and Monte Carlo simulation with 2 mm/2% and 3 mm/3% gamma criteria. The dose distribution in central plane and dose profiles from Pinnacle calculation were almost in agreement with both the Monte Carlo simulation and Delta4 measurement. The DVH plot have slightly differences between Pinnacle and Delta4 measurement as well as Pinnacle and Monte Carlo simulation, but have excellent agreement between Delta4 measurement and Monte Carlo simulation. Conclusions It was shown that all the three methods can be used very efficiently to verify esophageal carcinoma IMRT delivery, Delta4 and Monte Carlo simulation no data missed. The primary advantage of Delta4 is the fact it can measure true 3D dosimetry while Monte Carlo can simulate in patients CT images but not in phantom.

Adolescent ; Aged ; Aspergillosis ; microbiology ; pathology ; Aspergillus ; isolation & purification ; Brain Diseases ; drug therapy ; microbiology ; pathology ; surgery ; Diabetes Complications ; microbiology ; Diagnosis, Differential ; Female ; Humans ; Male ; Mucorales ; isolation & purification ; Mucormycosis ; drug therapy ; pathology ; surgery ; Nose Diseases ; drug therapy ; microbiology ; pathology ; surgery

Objective To investigate the role of electromyography(EMG) in diagnosis of nervous system diseases in children.(Met)-hods EMG tests were carried out in 354 patients with nervous system diseases,and the data and results of EMG tests were analyzed.Results One hundred and sixty-six patients′ results of EMG were abnormal.Among these abnormalities,36 cases were myogenic,47 cases were neurogenic,abnormalities of 69 cases were located in peripheral nerves,3 cases got positive in repetitive nerve stimulation(RNS),and 11 cases were on the borderline.In 36 myogenic patients,clinical diagnosis were as follow: progressive muscular dystrophy(PMD,18 cases),polymyositis(2 cases),mitochondrial encephalomyopathy(1 case), and the other 15 cases had no definite diagnosis.In 47 neurogenic patients,the diagnosis were spinal muscular atrophy(SMA,29 cases),sequela of poliomyelitis(2 cases),acute transverse myelitis(ATM,4 cases),and the other 12 patients had no definite diagnosis.In 69 cases of peripheral nerve abnormality,diagnosis were injury of brachial nerve(23 cases),hereditary motor sensory neuropathy(HMSN,2 cases),Guillain-Barre syndrome(GBS,9(ca)-ses),chronic inflammatory demyelinating polyradiculoneuropathy(CIDP,1 case),injury of facial nerve(4 cases),injury of common(pe)-roneal nerve(6 cases),metachromatic leukodystrophy(MLD,1 case),and the other 23 patients had no definite diagnosis.Three patients who got RNS positive were all diagnosed myasthenia gravis(MG),and ocular type(1 case),general type(2 cases).Eleven patients whose EMG results were borderline were all diagnosed indefinitely.One hundred and eighty-eight patients had normal results of EMG test.The diagnosis of these patients were included ocular MG(21 cases),cerebral palsy(CP,5 cases),ATM(2 cases),polymyositis((1 case)),and some other nervous system diseases(21 cases),and the other 138 were diagnosed indefinitely.Conclusions 1.EMG plays an important role in definite diagnosis of PMD,SMA,poliomyelitis and nerve injury;2.EMG can provide clue or basis in the differential(dia)gnosis of nervous system diseases which involved lower motor unit;3.EMG test has very low positive results in children with MG;(4.EMG) has little help in diagnosis of diseases involved upper motor unit only.

Animals ; Animals, Newborn ; Hypothyroidism ; genetics ; Myocardium ; metabolism ; RNA, Messenger ; genetics ; Rats ; Rats, Wistar ; Receptors, Thyroid Hormone ; genetics

Objective To explore the clinical feature of acquired pure amegakdryocytic thrombocytopenic purpura(AATP).Methods 18 patients were analyzed retrospectively.And 112 patients with ITP in the same term were to be control group.Each group's megakaryocytic (MK),platelet (PLT) count,mean platelet volume (MPV) and platelet associated immunoglobulin G(PAIgG) were rested.Results The MK total number of AATP group was obvious decreased or even absent,while the ITP group was increased[(0.8?1.5) vs (195.0?47.3),P0.05).About the PAIgG posi- tive rate,AATP group was 55.6 % while ITP group was 83% (P

The bioactivity of a working reference standard was determined by replicate bioassays with calibration against a primary reference standard. In this study the number of bioassay replicates needed for calibration first was calculated theoretically, and if the mean value of the experimental bioassay replicates fell within the predefined bioactivity level the bioactivity of the working reference was defined as 100%. Our results showed that when the total intermediate precision of the bioassay method was at 11.66% and the predefined bioactivity level was set at 95%-105% with a confidence level of 95%, 21 bioassay replicates should be carried out for calibration. The average value of the 22 experimental bioassay replicates was 101.96%, so the bioactivity of the working reference standard was consistent with that of the primary reference standard at 100%. The results suggest that a strategy of first calculating the number of bioassay replicates needed for calibration and then determining whether the resulting experimental mean value is within the predefined bioactivity level will be of value to the biopharmaceutical industry.

Abstract: AIDS combined with Pneumocystis jirovecii pneumonia (PJP) and disseminated infections of Talaromyces marneffei and Cryptococcus neoformans are rare. This paper summarizes and analyzes the diagnosis and treatment of an AIDS patient with multiple fungal infections for reference. A 79-year-old male patient was admitted to the hospital with "stool habit change for more than 20 days". The white blood cell count was 4.57×109/L, the percentage of neutrophils was 81.8%, the absolute count of CD4+ lymphocytes was 6/μL, and the CD4/CD8 ratio was 0.17. HIV antibody positive was confirmed by CDC. The cerebrospinal fluid and alveolar lavage fluid were positive for Cryptococcus neoformans capsular antigen, and Pneumocystis jirovecii was found by the bronchoalveolar lavage fluid stained with hexamine silver. The cerebrospinal fluid culture was positive for Cryptococcus neoformans, and the blood culture was positive for Cryptococcus neoformans and Talaromyces marneffei. CT showed that bronchovascular bundles in both lungs were more thick, patchy and cable-like high-density shadows were seen in both lungs, and the edges were blurred. Nodular and cable-like high-density shadows were seen in the posterior apical segment of the left upper lobe, with clear margins. Infection of both lungs was considered, and secondary pulmonary tuberculosis occurred in the left upper lobe. After admission, the patient was treated with various anti-bacterial and fungal drugs due to recurrent fever, but the effect was not effective. The fever symptoms of the patient could not be significantly improved, and his condition continued to worsen, and he eventually died. The patient with AIDS complicated with bacterial and fungal infection, especially PJP infection in serious condifiton and has a poor prognosis for rapid development, so clinical attention should be paid to.