Overexpression of CYP46A1 has anti-Alzheimer's disease like effects / 解放军医学杂志

Objective To investigate the effect of CYP46A1 on the pathogenesis of Alzheimer's disease.Methods Recombinant lentiviral vectors which including anthropogenic CYP46A1 were injected into bilateral hippocampus of 3-monthold male 5XFAD transgenic mice,while empty vectors were injected into the corresponding position of the control group.After two months,the ability of learning and memory were tested by Morris water maze and T maze experiments,and amyloid plaque and inflammatory infiltration in the brain were detected by immunohistochemical staining and ELISA respectively.Results Compared with the control group,CYP46A1 virus injection significantly increased the CYP46A1 mRNA and protein expression in hippocampus.In addition,CYP46A1 overexpression significantly decreased the latency to find the platform in Morris water maze test and increased the correct rate to choose in T maze test.Aβ immunohistochemical staining and plaques area statistics demonstrated that the amyloid plaque area of hippocampus in CYP46A1 overexpression mice was significantly reduced,and there was a significantly decrease of hippocampal astrocytes expression by means of GFAP staining.Furthermore,hippocampal CYP46A1 overexpression significantly decreased the expression level of Aβ40,Aβ42,IL-1β and TNF-α,while compare with the control group.Conclusion CYP46A1 overexpression in hippocampus can promote the cognitive impairment,as well as ameliorate the brain inflammatory infiltration in 5XFAD transgenic mice,suggesting that CYP46A1 has anti-Alzheimer's disease like effects.

Study on the characteristics of Tsutsugamushi disease in the epidemic areas of south islands in China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the increasing incidence and the characteristics of Tsutsugamushi disease in the areas of Nan Peng Lie islands, Nan Ao island, Wan Shan archipelago, Nao Zhou island and Lei Zhou peninsula, located in the southern part of China and to develop strategies for preventive measures.</p><p><b>METHODS</b>Both epidemiological investigation, isolation and gene identification of Orientia tsutsugamushi, as well as pilot preventive measures were carried out.</p><p><b>RESULTS</b>These islands belonged to the epidemic area of south subtropical zone of Tsutsugamushi disease. The main host was Rattus norvegicu and the overall rates of infection on Orientia tsutsugamushi were 22.78%-33.75%. The main biological vector was Leptotrombidium (Leptotrombidium) deliens and the rates of infection on Orientia tsutsugamushi were 40.00%-75.00%. 25 strains of Orientia tsutsugamushi had been isolated from Rattus norvegicu and Leptotrombidium (Leptotrombidium) deliens. Results showed that the isolated strains of Orientia tsutsugamushi were 15 Karp, 8 Kato, 2 Yonchon. Results from serological studies showed that the positive rate of anti-Orientia tsutsugamushi antibodies was high, in both residents and soldiers stationed in these islands. On these islands, rats and biological vectors were killed. Results showed that these measures had positive impact in reducing the incidence.</p><p><b>CONCLUSION</b>Islands from the southern part of the country belonged to the epidemic area of Tsutsugamushi disease. People visiting this areas should be under protection.</p>

Set-up uncertainties with radiation therapy for nasopharyngeal carcinoma / 中华放射肿瘤学杂志

Objective This study is to investigate the set-up accuracy of thermoplastic mask used for immobilization of nasopharyngeal carcinoma (NPC) patients being treated by Intensity Modulated Radia- tion Therapy (IMRT).Methods Nineteen patients with early stage nasopharyngeal carcinoma (T1- T2N0M0),treated by fractionated intensity-modulated radiation therapy,underwent repeated CTs during their 6-week treatment course.We evaluated their anatomic landmark coordinates in a total of 85 repeated CT data sets and respective x,y and z shifts relative to their position in the 19 treatment-planning reference CTs.Results The translation in x,y,and z-axes with their mean value derived from both positive and negative set-up errors was-0.84 mm(x-axis),+0.65 mm(y-axis) and +0.01 mm(z-axis).Mean target isocenter translation was (0.89?0.69) mm,(0.82?0.79) mm,(0.95?1.24) mm in x,y and z-direc- tions,respectively.The mean total magnitude vector and 95% CI of isocenter motion were 1.87 mm and 4.65 mm.The data measured over the 6-week fractionated course of treatment revealed a slight deterioration of isocenter accuracy.The 95% CI,considered by us to be a valuable parameter for characterizing the sys- tem,of 4.17 mm for measurement within the first 3 weeks increased to 5.12 mm in the last 3 weeks of treat- ment.Conclusions The sequential CT scanning is a pronounced valuable method of evaluating the quality of departmental specific patient positioning procedures.The thermoplastic mask is eyed as well suited tool for immobilization and repositioning of NPC patients receiving intensity-modulated radiation therapy.

Study on DNA fingerprinting of Mycobacterium tuberculosis strains isolated in Southern Chinese army by IS6110-restriction fragment length polymorphism / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the correlation between DNA fingerprinting of Mycobacterium tuberculosis (MTB) stains isolated from the Chinese army in the south and from local residents, and to investigate the molecular epidemiological characteristics of tuberculosis (TB) in the army, for the sake of TB prevention in the army.</p><p><b>METHODS</b>MTB DNA was digested with restriction endonuclease PvuII and electrophoresed in agarose gel, after Southern Blotting, the membrane was hybridized with a 245 bp fragment of IS6110 which labeled [alpha(32)P]-dCTP as probe. Finally, a restriction fragment length polymorphism (RFLP) patterns was shown, and analyzed logestic with epidemiological data from the patients.</p><p><b>RESULTS</b>A total number of 185 TB strains were detected and the IS6110 copy numbers ranged from 1 - 22. No significant difference was found in the IS6110 copy numbers between patients from army and local patients. IS6110 copy numbers of TB strains in army patients were centered in 6 - 20, however, with 7 - 20 copies in local TB patients. The TB strains were dispersed into 8 groups and the majority of TB strains in both army and local patients was centered in groups I, II, III. The distribution of DNA fingerprint for drug resistance TB strains was significantly different from those for sensitive strains. No different distribution of among groups was found regarding BCG history.</p><p><b>CONCLUSIONS</b>The genetics of TB stains were roughly the same between the army patients and local ones, but there was a strong correlation in the gene levels. Data suggested that a close connection should be considered on TB prevention and treatment for TB patients in the army and local residents.</p>

HBV C gene mutation in the transmission from father to infant / 中华儿科杂志

<p><b>OBJECTIVE</b>Hepatitis B virus (HBV) DNA was detected from infants whose mothers were negative for all HBV markers and the fathers were HBV carrier, the homology of HBV sequence of fathers and fetus was high, and HBV mutations concentrated on some points, and the transmission of HBV from father to fetus was also identified in some reports. The present study aimed to study HBV transmission from father to infant.</p><p><b>METHODS</b>The study enrolled 16 pairs of fathers who were HBV carriers and infants whose mothers were negative for HBV markers. The infants had evidences for intrauterine HBV infection. The five HBV serum markers HBsAg, HBeAg, anti-HBe, anti-HBs, and anti-HBc were detected with ELISA. The positive results for HBsAg and/or HBeAg were regarded as markers of HBV infection. Amplification of HBV DNA was done using a nested PCR method. The first amplification was carried out using primer C1 (nt 2394-2370), and primer C3 (nt 1730-1754). The second amplification was carried out using primer C2 (nt 1955-1974) and primer C6 (nt 2348-2330). Both primers were designed to amplify the part of sequence coding for the hepatitis B C antigen. The size of the amplified fragment obtained by the nested PCR was expected to be 394 bp. The PCR products were electrophoresed on 1.5% agarose gels, which were then stained with ethidium bromide and observed with ultraviolet transillumination. When 394 bp specific band was detectable, the sample was designated positive. Then the positive samples were identified by dot blot. The second PCR products were extracted by phenol-chloroform and 70% ethanol precipitation, then resuspended in TE buffer (pH8.0), and used as the template for cloning. The template was connected into pGEM-T vector by ligase. The ligated products were cloned into fresh competent JM109 cells, and incubated for 90 minutes at 37 degrees C on roller drum. Finally several dilutions were plated on plates containing ampicillin, X-Gal and IPTG, and incubated at 37 degrees C overnight. The white colony on plates was used for identification by the nested PCR with the above primers. When the 394 bp band was detectable by electrophoresis of PCR products in 1.5% agarose gels, the colony was designated positive; a positive colony was incubated in LB medium for 8 to 12 hrs, then plasmid was extracted using the Wizard Plus SV Minipreps DNA Purification System Kit (Promega). The purified plasmid was sent to Beijing Saibaisheng Company for sequencing. The homology of HBV C nt 2022-2301 sequence was compared between fathers and infants.</p><p><b>RESULTS</b>The homology of HBV C nt 2022-2301 sequence were 99% - 100% in 16 pairs of fathers and infants. The results were referred to the published sequence of HBV adw/adr clones, and the nucleic acid databases were searched for homology by using BLAST tool on Internet. HBV of the sixteen pairs of father/infant was closely related to the Japan strain (Genebank accession number AF121249), but there were still 17 more mutations at nucleotide positions 2029, 2034, 2044, 2059, 2078, 2095, 2104, 2154, 2161, 2169, 2189, 2201, 2233, 2251, 2284, 2288, 2293. Moreover the mutations at positions 2189, 2288 resulted in the substitution of the encoded amino acid (corresponding to amino acid positions 97 and 130, respectively), the other mutations at the position were nonphenotypic. The mutation of 2189, 2288 nucleotide of HBV C gene caused 97, 130 amino acid substitution for isoleucine to leucine and proline to threonine. The mutation of 2189, 2288 nucleotide of HBV C gene were detected in 6 (37.5%) of 16 pairs of fathers and infants.</p><p><b>CONCLUSION</b>The HBV transmission from father to infants did exist. The main HBV C gene mutation strains also existed in the transmission.</p>