Background The occurrence and development of aortic aneurysm (AA) are associated with infection.Some researchers have detected the DNA of periodontal pathogens in AA samples in certain populations.However,it has not been done in Chinese population.The objective of this study was to evaluate the prevalence of periodontal pathogens in oral tissue samples and aneurysm samples of AA patients.Methods Eighty-nine subjects with AA and 59 subjects without AA were examined.Periodontal clinical parameters were evaluated.Unstimulated saliva and subgingival plaque somples were collected from all subjects.Twenty-six dissected AA samples were obtained.Evidence of eight periodontal pathogens including Porphyromonas gingivalis (Pg),Actinobacillus actinomycetemcomitans (Aa),Prevotella intermedia (Pi),Tannerella forsythensis (Tf),Treponema denticola (Td),Campylobacter rectus (Cr),Fusobacterium nucleatum (Fn),and Prevotella nigrescens (Pn) was ascertained in all samples by 16S rRNA-based polymerase chain reaction (PCR) assay.Results The periodontal indexes including plaque index (PLI),probing depth (PD),bleeding index (BI),and clinical attachment loss (CAL),of the six Ramfjord index teeth were significantly higher in the AA group than those in the control group (P ＜0.01).Eight periodontal pathogens in subgingival plaque samples were more frequently detected in the AA group than in control group.The difference in prevalence between the groups was significant for six (out of eight) periodontal pathogens assayed (Pg,Pi,Fn,Pn,Tf,and Td,P ＜0.01).Additionally,all eight periodontal pathogens were more frequently detected in saliva samples of the AA group than in those of the control group,again with six (out of eight) (Pg,Pi,Fn,Cr,Tf,and Td) displaying significant differences in prevalence between the two groups (P ＜0.01).Out of 26 aneurysm samples examined,Pg,Pi,Fn,Crand Tfwere detected in 6 (23.1％),2 (7.7％),3 (11.5％),1 (3.8％),2 (7.7％),respectively,and Aa,Pn,and Td were not detected in dissected aneurysm samples.Conclusion Results of this study suggested that periodontal infection is associated with the occurrence of AA.

AIMTo explore the molecular biological mechanism of hemoglobin with high oxygen affinity in Tibetans by determining the sequence of globin cDNA in Tibetans living at high altitude.

METHODSTotal RNA was isolated from human bone marrow samples of three Tibetans who live in Qinghai-Tibet plateau. cDNA fragments coding for alpha and beta genes of human hemoglobin were obtained through RT-PCR and were ligated to plasmid pGEM-T easy vectors, and then the ligation liquid were transformed to Escherichia coli and cloned and sequenced. Nucleotide sequences were compared with GenBank data by BLAST method.

RESULTSsequence of a globin cDNA in Tibetans were the same with the registering globin genes in the GenBank, and Hb Abruzzo (beta143 (H21), His- > Arg) gene mutation, a high oxygen affinity beta globin mutation, was found in one Tibetan' beta goblin coding gene (CAC- > CGC).

CONCLUSIONThis hemoglobin gene mutation may be associated with high altitude adaptation of Tibetans living at high altitude.

Adult ; Altitude ; Asian Continental Ancestry Group ; genetics ; Cloning, Molecular ; DNA, Complementary ; genetics ; Hemoglobins, Abnormal ; genetics ; Humans ; Male ; Middle Aged ; Molecular Sequence Data ; RNA ; Sequence Analysis, DNA ; Tibet ; alpha-Globins ; genetics ; beta-Globins ; genetics

BACKGROUND: It is quite difficult to produce a decellularized lung scaffold, in which cells are removed and the extracellular matrix components (ECM) are preserved effectively. Perfusion of detergent-enzymes is an effective method with wide applications for decellularized lung scaffolds. OBJECTIVE: To investigate the effects of two detergents (sodium deoxycholate, SDC and sodium dodecyl sulfate, SDS) on the preparation of decellularized lung scaffolds. METHODS: Twenty-four male Sprague-Dawley rats were randomized into three groups: control group with no intervention, SDC group and SDS group. Decellularized lung scaffolds were prepared by perfusion of SDC or SDS combined with enzymes. The rat lung tissues in the three groups were taken for histological staining, immunofluorescent staining and DNA quantification. A549 cells were cultured and seeded onto the decellularized lung scaffolds for 7 days followed by hematoxylin-eosin staining. The decellularized lung scaffolds prepared by perfusion of SDC or SDS were subcutaneously implanted into the rat back, and the implants were retrieved and assessed by Masson staining after 2 weeks. RESULTS AND CONCLUSION: In the control group, there were abundant cells in the lung tissues. In the other two groups, the decellularized lung scaffolds were nearly transparent, and the morphology of the SDC scaffold was more close to the native lung. There were no residual cells and nuclei on the two scaffolds, and the DNA content in the SDS and SDC groups was significantly lower than that in the control group (P＜ 0.01). At 7 days of culture, A549 cells cultured on the SDS and SDC scaffolds migrated from the edge to the center of the scaffold. Comparatively speaking, the migration ability of A549 cells on the SDC scaffolds was stronger, and there was obvious cell invasion and growth in the middle part of the lung. After 2 weeks of scaffold transplantation, the SDC implants poorly fused with the surrounding tissues, with a clear boundary, a large number of infiltrating cells distributed evenly, and intravascular blood cells were clearly visible; the number of new blood vessels with larger diameter in the SDC scaffold was significantly higher than that in the SDS scaffold. These findings indicate that the SDC scaffold has better biocompatibility than the SDS scaffold, which can fuse with the surrounding tissues faster and produce more infiltrating cells and new blood vessels.

OBJECTIVETo study the epidemiology of genotyping Yersinia pestis isolated in the fulminant epidemics of human plague in Qinghai province in 2004.

METHODSPrimer pairs targeting the twenty-three different identified regions (DFRs) were designed to detect the presence or deletion of each DFR in 13 strains of Yersinia pestis isolated from the fulminant epidemic of human plague in Qinghai province in 2004.

RESULTSThere were 4 genomovars, i.e. Genomovar 8, 10, 15 and 16 in the 13 strains of Yersinia pestis identified. The genomovar of all the strains of Yersinia pestis isolated from Nangqian county was Genomovar 10. Among the two strains of Yersinia pestis isolated from Wulan county, the genomovar of one strain was Genomovar 8 and the other was Genomovar 10. The genomovars of all the strains of Yersinia pestis isolated from Qilian, Qumalai and Chengduo county belonged to Genomovar 16.

CONCLUSIONIt was demonstrated that the genotyping of Yersinia pestis appeared to be a powerful tool for investigating human plague epidemics.

China ; epidemiology ; Disease Outbreaks ; Genotype ; Humans ; Molecular Epidemiology ; Plague ; epidemiology ; Yersinia pestis ; genetics ; isolation & purification

OBJECTIVETo study whether plasma viral load testing is helpful to exclude ones free from Human immunodeficiency virus (HIV) infections from suspects in HIV antibody detections.

METHODS19 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.

RESULTSNone 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.

CONCLUSIONWhen 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.

AIDS Serodiagnosis ; HIV Antibodies ; blood ; HIV Infections ; blood ; diagnosis ; Humans ; Viral Load

OBJECTIVEAlthough HIV-1 infection is prevalent in many regions in China, it remains largely unknown on the biological characteristics of dominant circulating isolates. This study was designed to isolate the circulating viral strains from different prevalent regions and to characterize their biological properties and neutralization sensitivity.

METHODSPrimary viruses were isolated from fresh PBMCs using the traditional co-culture method and their capacity of inducing syncytium was tested in MT-2 cells. Meanwhile, their coreceptor usage was determined with two cell lines: Magi and GHOST (3) stably expressing CD4 and the chemokine receptor CCR5 or CXCR4. Furthermore, the sensitivity of these viruses to neutralization by HIV-1-infected patients' plasma which were highly active to neutralize SF33 strain, was quantified in GHOST cell-based neutralization assay.

RESULTSSix primary viral strains were isolated from 4 separated regions. Isolates LTG0213, LTG0214 and XVS032691 induced syncytia in MT-2 cells, and used CXCR4 as coreceptor. Isolates XJN0021, XJN0091, or SHXDC0041 did not induce syncytia, and used CCR5 as coreceptor. Overall neutralization sensitivity differed among four representative strains: HIV-1 XVS032691 > LTG0214 >XJN0091 approximately SHXDC0041.

CONCLUSIONThe neutralization sensitivity of HIV isolates is linked with the phenotype of isolates, in which syncytium-inducing (SI) or CXCR4-tropic (X4) viruses are more easily neutralized than non-syncytium-inducing (NSI) or CCR5-tropic (R5) viruses. The genetic subtypes based on the phylogeny of env sequences are not classical neutralization serotypes.

CD4-Positive T-Lymphocytes ; metabolism ; Cell Line ; Cells, Cultured ; Chemokines ; genetics ; immunology ; China ; Coculture Techniques ; methods ; Giant Cells ; ultrastructure ; virology ; HIV Infections ; virology ; HIV Seropositivity ; genetics ; immunology ; HIV-1 ; immunology ; isolation & purification ; physiology ; Humans ; Neutralization Tests ; Receptors, CCR5 ; metabolism ; Receptors, CXCR4 ; metabolism ; Virus Replication

OBJECTIVETo 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).

METHODSFour 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.

RESULTSSensitivity, 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%.

CONCLUSIONThe 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.

Blotting, Western ; methods ; China ; Enzyme-Linked Immunosorbent Assay ; methods ; HIV Infections ; diagnosis ; Humans ; Sensitivity and Specificity

OBJECTIVETo 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.

METHODSBlood 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.

RESULTSAmong 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_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_AE and CRF07_BC respectively. Subtypes B were predominant in Beijing, accounted for 40.9% among 22 samples.

CONCLUSIONFive HIV-1 subtypes were identified in Beijing and the surveillance of HIV-1 gene variation should be paid more attention to.

China ; HIV-1 ; classification ; genetics ; Humans ; Polymerase Chain Reaction ; Reverse Transcriptase Polymerase Chain Reaction ; env Gene Products, Human Immunodeficiency Virus ; genetics ; gag Gene Products, Human Immunodeficiency Virus ; genetics

OBJECTIVETo study the distribution of genomovars and microevolution of Yersinia pestis in the Qinghai-Tibet Plateau.

METHODSPrimer pairs targeting the twenty-two different regions(DFRs) were designed for detecting the presence or deletion of each DFR in 297 strains isolated from the Qinghai-Tibet Plateau.

RESULTS9 genomovars, i. e. Genomovar 1, 5, 6, 7, 8, 10, 11, new type and Ype-ancestor were identified in the Marmota himalayana plague focus of the Qinghai-Tibet Plateau. Among these genomovars, genomovar 5,8 and 10 were dominant types. The total rate of the three genomovars was 80.6% (204/253) and the genomovars in different regions were different. All of 44 strains of Y. pestis in the Microtus fuscus plague focus of the Qinghai-Tibet Plateau belonged to genomovar 14.

CONCLUSIONThe distribution of genomovars of Y. pestis in the Qinghai-Tibet plateau had remarkable characteristics geographically. Based on the distribution of genomovars of Y. pestis, the routes of transmission and microevolution of Y. pestis were proposed.

Biological Evolution ; China ; Geography ; Humans ; Plague ; transmission ; Yersinia pestis ; genetics

BACKGROUND: Previous Caucasian studies have described venous thromboembolism in pregnancy; however, little is known about its incidence during pregnancy and early postpartum period in the Chinese population. We investigated the risk of venous thromboembolism in a “real-world” cohort of pregnant Chinese women with no prior history of venous thromboembolism. METHODS: In this observational study, 15,325 pregnancies were identified in 14,162 Chinese women at Queen Mary Hospital, Hong Kong between January 2004 and September 2016. Demographic data, obstetric information, and laboratory and imaging data were retrieved and reviewed. RESULTS: The mean age at pregnancy was 32.4±5.3 years, and the median age was 33 years (interquartile range, 29–36 yr). Pre-existing or newly diagnosed diabetes mellitus was present in 627 women (4.1%); 359 (0.7%) women had pre-existing or newly detected hypertension. There was a small number of women with pre-existing heart disease and/or rheumatic conditions. Most deliveries (86.0%) were normal vaginal; the remaining were Cesarean section 2,146 (14.0%). The incidence of venous thromboembolism was 0.4 per 1,000 pregnancies, of which 83.3% were deep vein thrombosis and 16.7% were pulmonary embolism. In contrast to previous studies, 66.7% of venous thrombosis occurred in the first trimester. CONCLUSION: Chinese women had a substantially lower risk of venous thromboembolism during pregnancy and the postpartum period compared to that of Caucasians. The occurrence of pregnancy-related venous thromboembolism was largely confined to the early pregnancy period, probably related to the adoption of thromboprophylaxis, a lower rate of Cesarean section, and early mobilization.
Asian Continental Ancestry Group ; Cesarean Section ; Cohort Studies ; Diabetes Mellitus ; Early Ambulation ; Female ; Heart Diseases ; Hong Kong ; Humans ; Hypertension ; Incidence ; Observational Study ; Postpartum Period ; Pregnancy ; Pregnancy Trimester, First ; Pregnant Women ; Pulmonary Embolism ; Venous Thromboembolism ; Venous Thrombosis