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Objective: To analyze the molecular epidemiological characteristic of HIV-1 B'/C strains prevalent in Beijing., Methods: Plasma samples were collected from 200 newly diagnosed HIV-1 B'/C individuals reported during 2006 to 2010 in Beijing. The gag gene fragments were amplified from RNA template extracted from plasma with reverse transcription (RT) and nested polymerase chain reaction (PCR). And the sequences were analyzed by phylogenetic methods and Entropy analysis., Results: A total of 159 sequences were successfully amplified from the gag genes of which 147 was CRF07_BC and 12 CRF08_BC. There were 3 main sub-clusters in CRF07_BC phylogenetic tree and they were named as sub-cluster IDU-Max (89 sequences), sub-cluster IDU-Min (22 sequences) and sub-cluster MSM (34 sequences) based on transmission.No international reference strain was closely related with these three sub-clusters except for one strain identified in Taiwan. All CRF07_BC recombinant strains were remarkable for their low interpatient diversity in gag genes (3.7%, 3.3% and 2.0% for isolates from IDU-Max, IDU-Min and MSM respectively).When compared with sub-cluster IDU-Max, there were 32 and 41 significantly different sites of nucleotide polymorphism compositions in sub-clusters IDU-Min and MSM., Conclusion: This is the first report of describing the existence of three main epidemic sub-clusters in CRF07_BC strains prevalent in Beijing. And IDU-Max sub-cluster is the dominant strain. The CRF07_BC in Beijing are less diverse than other strains and may be derived from a common ancestor.

Sansevieria trifasciata originates from tropical West Africa. It is widely planted as a potted ornamental in China for improving indoor air quality (1). In February 2011, leaves of S. trifasciata plants in an ornamental market of Anle, Luoyang City, China, were observed with sunken brown lesions up to 20 mm in diameter, and with black pycnidia present in the lesions. One hundred potted plants were examined, with disease incidence at 20%. The symptomatic leaves affected the ornamental value of the plants. A section of leaf tissue from the periphery of two lesions from a plant was cut into 1 cm 2 pieces, soaked in 70% ethanol for 30 s, sterilized with 0.1% HgCl 2 for 2 min, then washed five times in sterilized distilled water. The pieces were incubated at 28°C on potato dextrose agar (PDA). Colonies of two isolates were brown with submerged hyphae, and aerial mycelium was rare. Abundant and scattered pycnidia were reniform, dark brown, and 200 to 350 × 100 to 250 μm. There were two types of setae on the pycnidia: 1) dark brown setae with inward curved tops, and 2) straight, brown setae. Conidia were hyaline, unicellular, cylindrical, and 3.75 to 6.25 × 1.25 to 2.50 μm. Morphological characteristics suggested the two fungal isolates were a Chaetomella sp. To confirm pathogenicity, six mature leaves of a potted S. trifasciata plant were wounded with a sterile pin after wiping each leaf surface with 70% ethanol and washing each leaf with sterilized distilled water three times. A 0.5 cm mycelial disk cut from the margin of a 5-day-old colony on a PDA plate was placed on each pin-wounded leaf, ensuring that the mycelium was in contact with the wound. Non-colonized PDA discs were placed on pin-wounded leaves as the control treatment. Each of two fungal isolates was inoculated on two leaves, and the control treatment was done similarly on two leaves. The inoculated plant was placed in a growth chamber at 28°C with 80% relative humidity. After 7 days, inoculated leaves produced brown lesions with black pycnidia, but no symptoms developed on the control leaves. A Chaetomella sp. was reisolated from the lesions of inoculated leaves, but not from the control leaves. An additional two potted plants were inoculated using the same methods as replications of the experiment, with identical results. To confirm the fungal identification, the internal transcribed spacer (ITS) region of rDNA of the two isolates was amplified using primers ITS1 and ITS4 (2) and sequenced. The sequences were identical (GenBank Accession No. KC515097) and exhibited 99% nucleotide identity to the ITS sequence of an isolate of Chaetomella sp. in GenBank (AJ301961). To our knowledge, this is the first report of a leaf spot of S. trifasciata caused by Chaetomella sp. in China as well as anywhere in the world. References: (1) X. Z. Guo et al. Subtropical Crops Commun. Zhejiang 27:9, 2005. (2) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, CA, 1990.

The development of sequencing technology allows low-cost generation of sequence data. The huge amount of raw sequence data now available has introduced many challenges associated with analysis of these large-scale data banks. For example, it is very important to distinguish materials of plant and fungal origin in fungus-infected plant tissue. The origin of transcripts that were sequenced from Library 895-M6 (poplar tissue infected by Marssonina brunnea) on Illumina/Solexa GA IIx was determined by combining three methods: (1) based on the taxonomic information of homologous sequences; (2) based on the reference genome sequence; (3) based on the transcriptome sequence of the host and its pathogen obtained from Library 895 (poplar) and Library M6 (M. brunnea) as well as Library 895-M6 (mixture of poplar and M. brunnea). We idenified accurately the origin of 80,978 (99.5%) contigs in the mixed poplar and M. brunnea sample (Library 895-M6) by integrating the results from the three methods. The results of this study demonstrate that a combination of these three approaches described here is an effective strategy for determining the origin of sequences in a mixed pool, and provides a basis for further transcriptome analysis of the mixed sample., (Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.)

Objective: To establish a simple and practical method for screening of Env-specific monoclonal antibodies from HIV-1 infected individuals., Methods: Human B cells were purified by negative sorting from PBMCs and memory B cells were further enriched using anti-CD27 microbeads. Gp120 antigen labbled with biotin was incubated with memory B cells to specifically bind IgG on cells membrane. The memory B cells expressing the Env-specific antibody were harvested by magnetic beads separating, counted and diluted to the level of single cell in each PCR well that loading with catch buffer containing RNase inhibitor to get RNAs. The antibody genes were amplified by single cell RT-PCR and nested PCR, cloned into eukaryotic expression vectors and transfected into 293T cells. The binding activity of recombinant antibodies to Env were tested by ELISA., Results: Three monocolonal Env-specific antibodies were isolated from one HIV-1 infected individual., Conclusion: We can obtain Env-specific antibody by biotin labbled antigen, magnetic beads separating technique coupled with single cell RT-PCR and expression cloning.

In the interaction between Pinus thunbergii and Bursaphelenchus xylophilus, nitric oxide (NO) is an important signaling molecule involving in the early response of P. thunbergii to the invasion of B. xylophilus. However, it is unclear that whether the NO production by P. thunbergii is triggered by the invaded B. xylophilus or its secreted metabolites. In the present study, the P. thunbergii was inoculated with living B. xylophilus, its secretion, and the suspension of grinded B. xylophilus, respectively, and the nitric oxide synthase (NOS) activity and NO content in the P. thunbergii were detected at the early stage. In all treatments, the inoculated P. thunbergii appeared disease symptoms, and the NOS activity and NO content in the P. thunbergii inoculated with B. xylophilus secretion and grinded B. xylophilus suspension increased, suggesting that besides living B. xylophilus, its contents or secretion could also trigger the expression of NO response signal in P. thunbergii, inducing the downstream response and causing the disease development of P. thunbergi. With the increasing temperature at 15-25 degrees C, both the NOS activity and the NO content in inoculated P. thunbergii increased, and the disease symptoms appeared earlier. The same patterns of NOS activity, NO content, and disease symptoms were also observed under increasing drought stress. It was suggested that within a definite range, increased. temperature and drought stress could enhance the NO signal expression in inoculated P. thunbergii and accelerate its disease development, and thus, the disease development of inoculated P. thunbergii under high temperature and drought condition could be related to the enhancement of the NO response signal in the host.

Objective: To analyze the molecular-epidemiological characteristics of HIV-1 strains prevailing among female people living with HIV in Beijing., Methods: Gag gene fragments from the 100 newly diagnosed female HIV-1 infections during 2006 to 2010 in Beijing were amplified, sequenced, and phylogenetically analyzed., Results: Eighty-two HIV-1 gag gene fragments were amplified and analyzed. 1 (1.22%), 1 (1.22%), 3 (3.66%), 23 (28.05%), 8 (9.76%), 2 (2.44%), 1 (1.22%), 18 (21.95%), 3 (3.66%), 1 (1.22%), 14 (17.07%), 4 (4.88%) and 3 (3.66%) individuals were infected with HIV-1 subtypes A1, A2, B, B', C, D, G, H, CRF01_AE, CRF02_AG, CRF07_BC, CRF08_BC and B'/C recombinants respectively., Conclusion: The subtypes circulating in female HIV infections in Beijing were more diverse than in male and the proportions of B' and rare subtypes were relatively high. Surveillance programs on HIV-1 genetic diversity should be strengthened.

Pine wilt disease (PWD) caused by the pine wood nematode (PWN), Bursaphelenchus xylophilus, is one of the most devastating diseases of Pinus spp. The PWN was therefore listed as one of the most dangerous forest pests in China meriting quarantine. Virulence of the PWN is closely linked with the spread of PWD. However, main factors responsible for the virulence of PWNs are still unclear. Recently epiphytic bacteria carried by PWNs have drawn much attention. But little is known about the relationship between endophytic bacteria and virulence of B. xylophilus. In this research, virulence of ten strains of B. xylophilus from different geographical areas in six provinces of China and four pine species were tested with 2-year-old seedlings of Pinus thunbergii. Endophytic bacteria were isolated from PWNs with different virulence to investigate the relationship between the bacteria and PWN virulence. Meanwhile, the carbon metabolism of endophytic bacteria from highly and low virulent B. xylophilus was analyzed using Biolog plates (ECO). The results indicated that ten strains of PWNs showed a wide range of virulence. Simultaneously, endophytic bacteria were isolated from 90% of the B. xylophilus strains. The dominant endophytic bacteria in the nematodes were identified as species of Stenotrophomonas, Achromobacter, Ewingella, Leifsonia, Rhizobium, and Pseudomonas using molecular and biochemical methods. Moreover, S. maltophilia, and A. xylosoxidans subsp. xylosoxidans were the predominant strains. Most of the strains (80%) from P. massoniana contained either S. maltophilia, A. xylosoxidans, or both species. There was a difference between the abilities of the endophytic bacteria to utilize carbon sources. Endophytic bacteria from highly virulent B. xylophilus had a relatively high utilization rate of carbohydrate and carboxylic acids, while bacteria from low virulent B. xylophilus made better use of amino acids. In conclusion, endophytic bacteria widely exist in B. xylophilus from different pines and areas; and B. xylophilus strains with different virulence possessed various endophytic bacteria and diverse carbon metabolism which suggested that the endophytic bacteria species and carbon metabolism might be related with the B. xylophilus virulence.

The content of NO and H(2)O(2) as well as the activities of nitric oxide synthase (NOS)-like and nitrate reductase (NR) were monitored in the needles of Pinus thunbergii infected by Bursaphelenchus xylophilus. The results showed that the content of NO increased significantly only 8 h after the invasion of B. xylophilus, while H(2)O(2) increased 12 h after invasion. NO donor SNP could promote and NO scavenger cPTIO could prevent the production of NO and H(2)O(2). The content of NO changed earlier than that of H(2)O(2). In addition, the symptoms appeared 9, 5 and 12 days, respectively, after the inoculation with B. xylophilus, SNP pre-treatment and cPTIO pre-treatment followed by B. xylophilus infection. After B. xylophilus infection, the content of NO in P. thunbergii changed fiercely more earlier than the appearance of external symptoms, which indicated that the content of NO was related with the appearance and the development of the symptoms. The treatment with L-NNA (NOS inhibitor) inhibited the content of NO significantly, whereas, Na(2)WO(4) (NR inhibitor) had no effect. The further analysis of NOS revealed that NO changed in consistent with cNOS activity. To sum up, NO, as the upstream signal molecule of H(2)O(2), was involved in the pine early response to the invasion of B. xylophilus and influenced the accumulation of the content of H(2)O(2). Moreover, NOS-like rather than NR was responsible for the endogenous NO generation, which was modulated by cNOS during the interaction between P. thunbergii and B. xylophilus. Key message NO is involved in early response of P. thunbergii to the invasion of B. xylophilus and NOS is the key enzyme responsible for NO generation in P. thunbergii.

Objective: To develop and evaluate an individualized fluid therapy in the elderly patients with coronary heart disease undergoing gastrointestinal surgery., Methods: In this prospective study, 60 coronary heart disease patients undergoing gastrointestinal surgery were included in the First Affiliated Hospital of Xinjiang Medical University from March 2009 to March 2012. Patients were randomized into the intervention group and the control group with 30 patients in each group. Individualized fluid therapy was used during surgery and postoperative period in the ICU, which was determined based on target controlled fluid therapy according to cardiac index, stroke volume, and stroke volume variation. Traditional fluid therapy was used in the control group in the intraoperative and postoperative period. The two groups were compared in terms of postoperative hemodynamic parameters, total fluid volume, incidence of adverse cardiac events, and recovery of bowel function., Results: Compared with the control group, mean arterial pressure was significantly increased at the commencement of the surgery. The cardiac index was significantly elevated during surgery and at the end of the surgery. Stroke volume was significantly increased after induction of anesthesia, during the surgery, and at the early stay of ICU period(all P<0.05). Serum lactic acid in the intervention group was significantly lower at the end of surgery and during ICU stay than that in the control group (all P<0.05). During surgery and 24-hour stay in ICU, the total fluid volume, crystal usage, and urine were significantly less, while colloidal fluid use was significantly more in the intervention group as compared to the control group(all P<0.05). The perioperative adverse cardiac event rate was 36.7%(11/30) in the intervention group, lower than 56.7%(17/30) in the control group, but the difference was no statistically significance(P>0.05). In the intervention group, defecation time, time to first flatus, resumption of liquid intake, length of ICU stay and hospital stay were significantly less compared with the control group(P<0.05)., Conclusion: In the elderly patients with coronary arterial disease undergoing gastrointestinal surgery, individualized fluid therapy can effectively decrease adverse cardiac events, improve postoperative gastrointestinal function, and reduce length of hospital stay.

To investigate the prevalence of HIV-1 genotypic mutations for drug resistance among patients in Beijing, blood samples from 145 newly confirmed (2006-2007), treatment-naive HIV-1-infected individuals were analyzed. Seven subtypes or CRF were subsequently determined and scored by the Stanford HIV Drug Resistance algorithm: CRF01&#95;AE HIV-1 (27.6%), subtype B' (24.1%), CRF07&#95;BC (21.4%), subtype B (20.7%), CRF08&#95;BC (3.4%), subtype C (2.1%), and CRF06&#95;cpx (0.7%). Eleven of the 145 subjects studied were found to harbor the strains resistant to either protease inhibitors (PIs) (3.4%), or nucleoside reverse transcriptase inhibitors (NRTIs) (2.1%), or nonnucleoside reverse transcriptase inhibitors (NNRTIs) (3.4%). Although the prevalence of drug resistance was relatively low among the treatment-naive HIV-1 patients in Beijing in comparison to those in industrialized countries, we will continue monitoring newly infected subjects for any potential alteration of the prevalence pattern to ensure the success of the ongoing scale-up of antiretroviral treatment.

The purpose of this study was to investigate the genetic diversity of HIV-1 circulating in Beijing and its molecular epidemiological linkages with regard to risk factors of viral transmission. HIV-1 from plasma samples of 280 diagnosed individuals (2006-2007) was characterized. The gene fragments of gag, pol, and env from the infected plasma samples were amplified by reverse transcriptase polymerase chain reaction (RT-PCR), sequenced, and phylogenetically analyzed. From the 280 plasma samples analyzed, a total of 496 sequences were successfully amplified from the gag, pol, and env genes. Nine HIV-1 group M subtypes or CRF including A1, B, B', C, CRF01&#95;AE, CRF02&#95;AG, CRF06&#95;cpx, CRF07&#95;BC, and CRF08&#95;BC, and six new B'/C recombinants were identified. CRF07&#95;BC was found to be the most dominant subtype (32.5%) followed by CRF01&#95;AE (25.0%), B (20.0%), and B' (15.7%). The data from this study indicate the existence of multiple HIV-1 subtypes or CRFs in Beijing and may be proven useful in the development of vaccine candidates in the future.

Objective: To assess whether goal-directed fluid management can prevent gastrointestinal complications in major surgery., Methods: Electronic databases including Cochrane library(Issue 3,2010), Pubmed, EMbase, Highwire, CBM, and CNKI were searched. The date of search was between January 2000 and December 2010. Randomized controlled trials(RCTs) were indentified studying association of goal-directed therapy (GDT) with gastrointestinal complications. Study selection and meta-analysis were conducted according to the Cochrane Handbook for systematic reviews. Data were extracted from these trials by 3 reviewers independently and analyzed by RevMan 5.0 software., Results: Ten trials involving 775 patients were included. GDT significantly improved oxygen supply(WMD=82.95, 95% CI: 17.43-148.46). GDT reduced postoperative hospital stay(WMD=-2.06, 95% CI: -2.95 - -1.17) and decreased postoperative complication rate after major surgery(RR=0.39, 95% CI: 0.29-0.52)., Conclusion: Goal-directed fluid management can stabilize cardiac output, augment oxygen supply, and therefore reduce postoperative complications.

Objective: To examine the prevalence of drug resistance mutations among the treatment-naive HIV (human immunodeficiency virus) infectors living in Beijing so as to provide the basal information for clinical antiviral treatment., Methods: HIV pol genes from plasma samples of 150 treatment-naive HIV-infected patients were amplified, sequenced and phylogenetically analyzed. And the drug-resistance associated mutations in protease and reverse transcriptase regions were analyzed with Stanford University HIV Drug Resistance Database., Results: A total of 111 pol gene sequences were obtained. The overall prevalence of drug resistance was 8.1% (9/111), corresponding to 3.6% (4/111) for protease inhibitors, 1.8% (2/111) for nucleoside reverse transcriptase inhibitors and 3.6% (4/111) for non-nucleoside reverse transcriptase inhibitors. No drug resistance mutation was identified in 17 intravenous drug users., Conclusion: The prevalence of drug resistance is relatively high in the newly confirmed HIV infectors in Beijing. Regular surveillance and monitoring of drug-resistant HIV should be implemented.

Little is known about the molecular and biological properties of HIV-1 intersubtype B'/C in Beijing. To fill the gap, we sequenced and analyzed the gag-pol genes from 39 HIV-1 B'/C recombinant infectors in Beijing, China during 2007. The results show that 36 CRF07&#95;BC and 2 CRF08&#95;BC isolates have a structural profile identical or nearly identical to CRF07&#95;BC or CRF08&#95;BC according to sequences in the gag-pol regions. The CRF07&#95;BC circulating in injecting drug users (IDUs) and heterosexuals forms a diverse phylogenetic tree and most isolates from homosexuals cluster together. However, all the B'/C recombinant strains were remarkable for their low interpatient diversity in gag-pol genes (3.1, 3.0, and 2.2% for isolates from IDUs, heterosexuals, and homosexuals, respectively). We identified I7V, E91G, N242T, and K361R in the gag gene and R290I (HXB2 positions) in the pol gene as signature amino acid substitutions characteristic of HIV-1 CRF07&#95;BC from the Beijing lineage. In addition, one new B'/C recombinant was detected. These results may contribute to an understanding of HIV-1 in Beijing.

Objective: To analyze the genetic characteristics of HIV-1 CRF01&#95;AE strains prevailing in Beijing., Methods: Plasma samples were collected from the newly diagnosed HIV-1 individuals being reported during 2006 to 2008 in Beijing. Gag gene fragments were amplified from RNA template which were extracted from plasma by RT and nested PCR methods. 105 CRF01&#95;AE sequences were analyzed by phylogcnetic methods and characterized through calculating the genetic distance and Entropy analysis., Results: There were four main sub-clusters in the phylogenetic tree. We named them as sub-clusters Homo-Max (67 sequences), Hetero (6 sequences), Mix (8 sequences) and Homo-Min (18 sequences) respectively, based on the mode of transmission. It was found that no international reference strain was closely related to the sub-cluster Homo-Max, Hetero or Homo-Min, including 91 samples. The strains in sub-cluster Mix consisting 8 cases that were closely related to the strains identified in Thailand and Vietnam. Genetic distance analysis on gag genes showed that the diversity of sub-clusters Homo-Max and Homo-Min was obviously less than that of the sub-cluster Hetero or Mix. When compared with sub-cluster Mix, there were 37, 29 and 11 significantly different nucleotides polymorphism compositions sites in sub-clusers Homo-Max Homo-Min and Hetero., Conclusion: This was the first report describing that four main epidemic sub-clusters were existed in CRF01&#95;AE strains prevailing in Beijing. The virus with sub-cluster Homo-Max was the dominant strain in this region with shorter period of circulation and higher proportion seen in the HIV-infected persons. The virus in sub-cluster Mix was highly homologic with the CRF01&#95;AE strains from Thailand and Vietnam.

To investigate the subtype distribution and sequence characteristics of HIV-1 strains prevalent in Beijing during 2007 and to analyze the relationship between distribution of HIV-1 subtypes and transmission routes, we collected the anti-conglutinated whole blood samples from HIV-1 newly infected individuals in Beijing during 2007 and separated plasma specimens from the aamples. RNAs were extracted and the gag genes from the various samples were amplified by RT-PCR and nest-PCR. The PCR products were sequenced directly and phylogenetic analyses of gag genes were performed using the MEGA2 software. Among 200 HIV-1 plasma samples,161 gag HIV-1 gene fragments were amplified and analyzed. Seven HIV-1 subtypes or circulating recombinant forms (CRFs) of HIV-1 including A1 (1 strains), B (35 strains), Thai B (19 strains), C (3 strains), CRF01&#95;AE (49 strains), CRF07&#95;BC (51 strains), CRF08&#95;BC (3 strain) were identified circulating in Beijing. The gene divergences inside the subtypes were different, with 7.7%, 6.5%, 6.7%, 6.7%, 5.5%, 4.3%, 5.8%, in subtype A1, B, Thai B, C, CRF01&#95;AE, CRF07&#95;BC, CRF08&#95;BC, respectively. Subtypes CRF07&#95;BC and CRF01&#95;AE were predominant in Beijing account for 31.7% and 30.4% among samples. Seven HIV-1 subtypes exist in Beijing and the surveillance of HIV-1 gene variation should be paid more attention.

Objective: To explore the bronchoscopic and CT findings of invasive tracheobronchial and pulmonary aspergillosis in patients without immunodeficiency., Methods: Clinical data and bronchoscopic and CT findings of 6 patients with tracheobronchial and pulmonary aspergillosis were reviewed from January 2004 to August 2008., Results: All the patients had no immunodeficiency diseases. The bronchoscopic findings mostly presented in 2 forms: single endobronchial nodule and ulcerative or pseudomembranous tracheobronchitis. The lesions were diffusely distributed or localized. Chest CT showed tracheal or bronchial wall thickening in the early stage, and with disease progression, local consolidation or multiple nodules and cavitation became the most common findings. The nodules and cavities were predominantly peribronchial. A solitary nodule was found in 2 patients. All the cases had been misdiagnosed as other diseases, and repeated courses of antibiotics or corticosteroids had been tried., Conclusions: Ulcerative or pseudomembranous tracheobronchitis and single nodule are the most common bronchoscopic findings of invasive tracheobronchial aspergillosis. Local consolidation, multiple nodules and cavitation with predominantly peribronchial distribution are the most common CT findings.

Background and Purpose: Atypical and malignant meningiomas are uncommon tumors with aggressive behavior and higher mortality, morbidity, and recurrence compared with benign tumors. We investigated the utility of diffusion-weighted (DW) MR imaging to differentiate atypical/malignant from benign meningiomas and to detect histologic dedifferentiation to higher tumor grade., Materials and Methods: We retrospectively compared conventional and DW MR images (b-value 1000 s/mm(2)) acquired on a 1.5T clinical scanner between 25 atypical/malignant and 23 benign meningiomas. The optimal cutoff for the absolute apparent diffusion coefficient (ADC) and normalized ADC (NADC) ratio to differentiate between the groups was determined by using receiver operating characteristic (ROC) analysis., Results: Irregular tumor margins, peritumoral edema, and adjacent bone destruction occurred significantly more often in atypical/malignant than in benign meningiomas. The mean ADC of atypical/malignant meningiomas (0.66 +/- 0.13 x 10(-3) mm(2)/s) was significantly lower compared with benign meningiomas (0.88 +/- 0.08 x 10(-3) mm(2)/s; P < .0001). Mean NADC ratio in the atypical/malignant group (0.91 +/- 0.18) was also significantly lower than the benign group (1.28 +/- 0.11; P < .0001), without overlap between groups. ROC analysis showed that ADC and NADC thresholds of 0.80 x 10(-3) mm(2)/s and 0.99, respectively, had the best accuracy: at the NADC threshold of 0.99, the sensitivity and specificity were 96% and 100%, respectively. Two patients had isointense benign tumors on initial DW MR imaging, and these became hyperintense with the decrease in ADC and NADC below these thresholds when they progressed to atypical and malignant meningiomas on recurrence., Conclusions: ADC and NADC ratios in atypical/malignant meningiomas are significantly lower than in benign tumors. Decrease in ADC and NADC on follow-up imaging may suggest dedifferentiation to higher tumor grade.

Objective: To study whether plasma viral load testing is helpful to exclude ones free from Human immunodeficiency virus (HIV) infections from suspects in HIV antibody detections., Methods: 19 Specimens, which showed disconcordant results of the two HIV EIA testing (S/CO < 6) and indeterminated results of Western blot (WB) test, were selected. Viral load of the specimens were detected. A six-month follow up survey in detecting HIV antibody was conducted in these subjects., Results: None of these 19 cases was observed to be positive HIV viral loads and there was no any progress in WB bands development during the follow-up period. The possibility of HIV infection could be excluded., Conclusion: When the specimens react with very low intensity in both EIA and WB, negative viral load result is conducive to exclude negative subjects from suspects in HIV antibody detections.

Objective: To identify a cost-efficient alternative antibody testing strategy for screening and confirmation of HIV infection by rapid simple tests (RSTs) and enzyme-linked immunosorbent assays (ELISAs)., Methods: Four RSTs (RST1, RST2, RST3, and RST4) and five ELISAs (ELISA1, ELISA2, ELISA3, ELISA4, and ELISA5) were evaluated in two phases by using banked and serum specimens prospectively collected at regional hospitals and voluntary counseling and testing (VCT) centers in Beijing. A total of 200 banked serum specimens were included in the first phase, including 62 HIV-positive, 127 HIV-negative and 11 indeterminate specimens. All specimens were tested by four RSTs and five ELISAs respectively. The second phase involved prospective testing of 389 routine specimens, including 92 HIV-positive, 287 HIV-negative, and 10 indeterminate specimens. All the specimens were tested by two RSTs (RST2 and RST4) and three ELISAs (ELISA1, ELISA3, and ELISA4), which were selected for their respective excellent sensitivity and/or specificity. Western blot (WB) was used as a gold standard for confirming the reactivity of all the specimens., Results: Sensitivity, specificity, and efficacy were calculated for each assay in two phases. In the first phase, four assays (ELISA4, RST2, RST3, and RST4) had a specificity of 100%. For the determination of efficacy, ELISA4, RST2, and RST4 were selected in the second phase. ELISA1 and ELISA3 which have a sensitivity of 95.9% and 93.2% respectively also entered this phase. In the second phase, all the five assays (ELISA1, ELISA3, ELISA4, RST2, and RST4) had a sensitivity and specifity of over 90%. ELISA1 had a sensitivity of 99% and ELISA4 a specificity of 99%., Conclusion: The sensitivity ELISA1 and the specificit of ELISA4 are comparable to ELISA/WB standard strategy. Application of this alternative testing strategy provides a cost-effective method for determining HIV prevalence in Beijing.

Objective: To investigate the subtype distribution and the prevalence of sequence characteristics of HIV-1 strains in Beijing residents during 2006 and to analyze the relationship between distribution of HIV-1 subtypes and transmission routines., Methods: Blood samples from 32 new confirmed HIV-1 infected individuals from Beijing residents in 2006 and separated plasma specimens were collected. RNAs were extracted and the gag and env gene were amplified by RT-PCR and nest-PCR. PCR products were sequenced directly and phylogenetic analyses of gag and env gene were performed using the MEGA2 software., Results: Among 32 HIV-1 plasma samples, 22 gag and 4 env gene fragments were amplified and analyzed. Five HIV-1 subtypes or circulating recombinant forms(CRFs) of HIV-1 including Thai B (2 strains), B (9 strains), C (2 strains), CRF07&#95;BC (5 strains), CRF01 AE (4 strains) were identified being circulated in Beijing. The gene divergences of gag gene inside the subtypes were 6.6%, 4.3%, 6.8%, 4.9% and 3.0% in subtype B, Thai B, C, CRF01&#95;AE and CRF07&#95;BC respectively. Subtypes B were predominant in Beijing, accounted for 40.9% among 22 samples., Conclusion: Five HIV-1 subtypes were identified in Beijing and the surveillance of HIV-1 gene variation should be paid more attention to.

Objective: To evaluate the open surgery as well as the endovascular treatment of abdominal aortic aneurysms (AAA) in octogenarians., Methods: Twenty AAA cases aging from 80 to 90 in the past six years were reviewed. Open surgery on 12 patients and endovascular repair on the other 8 ones were performed., Results: During peri-operation, there were 2 mortality from the surgical group among all 20 cases. The endovascular group underwent significantly better operational procedure and complication situation than the surgical one. Eighteen cases were followed up for 3-69 months (average months) except for 2 patients of surgical group. Both group suffered 2 late mortality. The accumulated survival rate were 6/10 in the surgical group and 6/8 in the endovascular group, respectively., Conclusion: Surgical treatment in applicable for octogenarians with AAA. The endovascular repair was preferable to suitable cases.

Objective: To study the methods of surgical treatment and the prognosis of acute embolism of the upper extremity., Methods: Balloon catheter embolectomy through the brachial artery was performed in 18 patients with acute embolism of the upper extremity., Results: Both the pulse of the radial and ulnar artery could be palpated in 8 patients, either the pulse of the radial or ulner artery could be palpated in 9 patients. The temperature of the upper extremity was increased in the patient whose embolectomy was performed in the 6th day after onset of the illness. Three patients died postoperatively., Conclusions: Embolectomy through the brachial artery is an effective method to treat acute embolism of the upper extremity. Elderly and heart and pulmonary diseases are the high risk factors for postoperative death.

291 patients were subjected to carotid endarterectomy from January 1985 to June 1992 in two Australian medical institutions. Of the 291 patients, perioperative stroke occurred in 22 (6.3%) after 347 operations (moderate 17 and severe 5). The 22 patients were studied with Doppler scan, angiography, reexploration and CT. Reexploration showed that 12 of 14 patients had thrombosis in the internal carotid artery at operation. The etiological factors for perioperative strokes included thrombosis at the operative sites in 14 patients (64%), cerebral embolism after operation in 4, clamping ischemia in 2, intracerebral hemorrhage in 1 and unknown cause in 1. Six patients (27%) recovered completely in 4 weeks, 10 (45%) had mild residual neurological deficits, 5 (23%) had moderate neurological deficits and 1 died 3 days after operation. Only 6 patients had permanent neurological deficits (6/347, 17%).

We treated successfully 9 patients with middle stage arterial embolism through both Fogarty catheter embolectomy and directly pouring thrombolytic agents into artery. In all patients the extremities were salvaged and symptoms disappeared. The patients were operated upon 15, 30, 60 hours and 3, 5, 8, 30, 39, 40 days respectively after onset of the disease. The indications for this treatment are dependent on how many hours last between onset and treatment and whether the extremity is gangrened. The main embolus in the greater artery can be removed by Fogarty catheter, while the thrombosis in smaller artery can be resolved by directly arterial luminal pouring thrombolytic agents, so the result is better if the two methods are combined.

During the 30 years from 1960 to 1989, 100 sequential patients with atherosclerotic infrarenal abdominal aortic aneurysm (AAA) were admitted to Zhongshan Hospital. Twenty-eight were not treated surgically and 72 underwent resection of the AAA with prosthesis replacement. Nineteen non-surgical patient were followed up, and 8 died from ruptures with a five-year survival rate of 41.3 +/- 13%. In 72 surgically treated patients, the operative mortality was 2.8%. The five-year survival rate is 77.5 +/- 6.2%, which is higher in comparison with the non-surgical group (P < 0.01). The data show that the operation for AAA is safe and the postoperative long-term results are satisfactory.

Sixteen patients with Takayasu's arteritis and a long-stenotic segment of the descending thoracic aorta and/or proximal and middle portion of the abdominal aorta, with or without renal artery stenosis, were treated by percutaneous transluminal aorto-angioplasty (PTAA). These patients might be subdivided into three groups: A. with normal renal artery, B. with severe renal artery stenosis or occlusion without treatment or with failure of dilatation, and C. with renal artery stenosis but relieved by percutaneous transluminal renal angioplasty (PTRA). It was found that the hypertension may be caused by the suprarenal aortic stenosis itself. PTAA has an excellent effect to normalize the blood pressure in Group A. The elevated blood pressure may also be decreased in various extent in the patient with severe renal artery stenosis after PTAA, but not to normal. An additional PTRA or other renal vesel reconstruction procedure is necessary in this group. No recurrence of the aorta stenosis was found by non-invasive examinations or aortography during the long-term follow-up. PTAA may be considered as the first choice for the aortic stenosis caused by Takayasu's arteritis.