[Advances in the construction of risk prediction models for chronic kidney failure].

Chronic kidney disease (CKD) is a major public health problem worldwide. When CKD patients progress to the stage of kidney failure, kidney replacement therapy (KRT) or conservative treatment (palliative or non-dialysis treatment) will be needed. The risk prediction models of chronic kidney failure have been developed in recent years. These models, focusing on demographic indicators, clinical indicators, and laboratory data, are used to predict the likelihood of progression to kidney failure and requiring KRT. This article will retrieve prediction models for chronic kidney failure as an outcome, demonstrate the current research progress, and hope that it may be helpful for the strategies of preventing chronic kidney failure.

[Analysis of on-demand adherence and related factors in men who have sex with men who access HIV pre-exposure prophylaxis services via the internet].

Objective: To understand the compliancy to on-demand HIV pre-exposure prophylaxis (PrEP) and related factors in men who have sex with men (MSM) accessing to PrEP service through an Internet platform. Methods: A cross-sectional study method was used to recruit survey respondents through the Heer Health platform from July 6 to August 30, 2022, and a questionnaire survey on the current status of medication use was conducted in MSM who use PrEP through the platform and take medication on demand. The MSM's information collected in the survey mainly included socio-demographic characteristics, behavioral characteristics, risk perception characteristics, PrEP awareness and the status of dose taking. Univariate and multivariate logistic regression analyses were used to evaluate factors related with compliancy to PrEP. Results: A total of 330 MSM who met the recruitment criteria were included during the survey period, with a valid response rate of 96.7% (319/330) to the questionnaire survey. The age of the 319 MSM was (32.5±7.3) years. Most of them had education level of junior college or college and above (94.7%, 302/319), most of them were unmarried (90.3%, 288/319), most of them had full-time works (95.9%, 306/319), and 40.8% of them had average monthly income ≥10 000 yuan (130/319). The proportion of the MSM with good compliancy to PrEP was 86.5% (276/319). The results of univariate and multivariate logistic analyses showed that the MSM with good awareness of PrEP had relatively better compliancy to PrEP compared with those with poor awareness of PrEP (aOR=2.43, 95%CI:1.11-5.32). Conclusions: The compliancy to on-demand PrEP was good in MSM who accessed to the services through Internet platform, but there is still a need to strengthen PrEP promotion in MSM for the further improvement of PrEP compliancy and reduction of the risk for HIV infection in this population.

B cells and tertiary lymphoid structures are associated with survival in papillary thyroid cancer.

PURPOSE: The function of B cells in papillary thyroid cancer (PTC) is controversial. The role of B-cell-related tertiary lymphoid structures (TLSs) is still unclear. Whether B cells exert their anti-tumor effect through forming TLS in PTC needs further investigation. METHODS: We detected the percentage of B cells in PTC tissues by multi-parameter flow cytometry. Paraffin-embedded tumor tissues of 125 PTC patients were collected and stained with Haematoxylin-Eosin (H&E) for inflammatory infiltration analysis in combination with clinical features. Multiplexed immunohistochemistry (mIHC) was performed to verify the TLSs in above inflammatory infiltration. Correlation of B cells and TLSs with prognosis was analyzed using the TCGA database. RESULTS: We observed that PTC patients with higher expression of B lineage cell genes had improved survival and the percentage of B cells in the PTC tumor tissues was variable. Moreover, PTC tumor tissues with more B cells were surrounded by immune cell aggregates of varying sizes. We furtherly confirmed the immune cell aggregates as TLSs with different maturation stages. By analyzing PTC data from TCGA database, we found the maturation stages of TLSs were associated with genders and clinical stages among PTC patients. Moreover, patients with high TLSs survived longer and had a better prognosis. CONCLUSION: B cells are associated with the existence of TLSs which have different maturation stages in PTC. Both B cells and TLSs are associated with the survival rate of PTC. These observations indicate that the anti-tumor effects of B cells in PTC are associated with TLSs formation.

[Research advances in HIV pre-exposure prophylaxis drug].

In 2012, the World Health Organization (WHO) released tenofovir/emtricitabine (TDF/FTC) as pre-exposure prophylaxis drug to help people at risk of HIV infection in specific populations, and various clinical trials and real-world data have confirmed the effectiveness of TDF/FTC in preventing HIV infection. In 2019, propofol tenofovir combined with emtricitabine (TAF/FTC) was approved in the United States as the second oral drug for pre-exposure prophylaxis(PrEP). However, for people who cannot take the drug or have poor adherence to the drug, second-generation PrEP, or long-acting antiretrovirals, provide more options. This artical reviewed the research progress of the first generation of oral PrEP and the new PrEP developed in recent years to provide reference for the promotion of HIV PrEP in China.

[The screening of potential biological markers of seizure onset zone in focal cortical dysplasia based on bioinformatics analysis].

Three patients diagnosed with focal cortical dysplasia (FCD) in the First Hospital of Peking University from September to November 2020 were recruited in the study. Based on stereotactic electroencephalogram (SEEG) or electrocorticogram (ECoG) analysis to localize the seizure onset zone (SOZ), RNA sequencing (RNA-seq) analysis was performed for the SOZ and para-SOZ tissue obtained from surgery. The differentially expressed genes between SOZ and para-SOZ samples were analyzed by performing Go (Gene ontology) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis."Extracellular matrix"was significantly enriched, which included collagen synthesis genes (e.g., COL1A1)."Ether lipid metabolism"was enriched in the KEGG pathway enrichment analysis. These differences could be the potential biological markers for SOZ localization.

[mTOR signaling pathway-mediated autophagy involved in inhibition of osteoblast differentiation induced by cadmium in human bone marrow mesenchymal stem cells].

Objective: To investigate the role of autophagy mediated by mTOR signaling pathway in the inhibition of osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) induced by cadmium. Methods: HBMSCs were divided into 0, 2.5 or 5.0 µmol/L groups according to the exposure dose of cadmium chloride (CdCl2), and each group was treated for 1 day, 4 days and (or) 7 days. The ALP activity and mRNA and protein expression levels of osteogenesis markers (ALP, RUNX2 and OSTERIX), autophagy-related proteins (LC3 and Beclin-1) and mTOR signaling pathway related proteins (mTOR, p-mTOR and p-p70S6K) expression, alkaline phosphatase staining and alizarin red staining were detected. MHY 1485 was selected as the signaling pathway activator. The control group, CdCl2 group (5.0 µmol/L), MHY 1485 group and CdCl2+MHY 1485 combined treatment group were set. After 7 days of treatment, the expression levels of autophagy related proteins and mTOR signaling pathway related proteins of hBMSCs in each group were detected. Results: There was no significant difference in ALP activity between 0, 2.5 and 5.0 µmol/L groups on day 1 and 4 (P>0.05); On day 7, compared with the 0 µmol/L group, the ALP activity, expression of osteogenic markers (ALP, RUNX2, OSTERIX) and mTOR signaling pathway related proteins (mTOR, p-mTOR, p-p70S6K) expression decreased in the 2.5 and 5.0 µmol/L group (P<0.05). Compared with the 0 µmol/L group, the staining of the 2.5 and 5.0 µmol/L groups became lighter, and the formation of ALP and mineralized nodules was reduced. Compared with the CdCl2 group, the autophagy related protein expression in the CdCl2+MHY 1485 combined treatment group decreased, and the mTOR signaling pathway related protein expression increased. The difference was statistically significant (P<0.05). Conclusion: The inhibition of osteogenic differentiation of hBMSCs by cadmium may be related to autophagy mediated by mTOR signaling pathway.

[Predictive factors of pathological complete response after neoadjuvant chemoradiotherapy for middle-low rectal cancer].

Objective: To explore the predictive factors of pathological complete response (pCR) after neoadjuvant chemoradiotherapy for middle-low rectal cancer. Methods: A case-control study was conducted. The inclusion criteria were as follows: (1) colonoscopy, digital examination or magnetic resonance imaging (MRI) showed a distance from the lower edge of the tumor to the dentate line of no more than 10 cm; (2) complete clinicopathological data were available; (3) preoperative biopsy revealed adenocarcinoma; (4) preoperative pelvic MRI or endorectal ultrasonography was performed; (5) no distant metastasis was found. Exclusion criteria: (1) preoperative radiotherapy and chemotherapy were not administrated according to the standard; (2) simultaneous multiple primary cancer and familial adenomatous polyposis were observed. According to the above criteria, clinicopathological data of 245 patients with middle-low rectal cancer undergoing preoperative neoadjuvant chemoradiotherapy in Changhai Hospital of Navy Medical University from January 2012 to December 2019 were retrospectively collected. Univariate analysis and multivariate logistic analysis were used to identify the clinical factors predicting pCR. pCR is defined as complete disappearance of cancer cells under the microscope in cancer specimens (including lymph nodes) after neoadjuvant chemoradiotherapy. Results: A total of 72 patients with pCR were enrolled in this study. Univariate analysis showed that preoperative T stage, tumor circumference, tumor morphology, carbohydrate antigen (CA) 19-9, interval between the end of neoadjuvant therapy and operation were associated with pCR (all P<0.05). The above 5 variables were included in multivariate logistic analysis and the results revealed that the T stage (OR=5.743, 95% CI: 2.416-13.648, P<0.001), tumor circumference (OR=7.754, 95% CI: 3.822-15.733, P<0.001), tumor morphology (OR=0.264, 95% CI: 0.089-0.786, P=0.017) and the interval between the end of neoadjuvant therapy and operation (OR=0.303, 95% CI: 0.147-0.625, P=0.001) were independent predictive factors of pCR, while CA 19-9 level was not an independent factor (OR=1.873, 95% CI:0.372-9.436, P=0.447). Conclusion: By knowing the clinical features of preoperative T stage, tumor circumference, tumor morphology and the interval between neoadjuvant chemoradiotherapy and operation, patients with higher likelyhood of pCR after neoadjuvant chemoradiotherapy may be identified.

[Hypoxia-inducible factor-1α is involved in arsenite-induced epithelial-mesenchymal transition and malignant transformation of human liver epithelial cells via regulating Snail].

Objective: To investigate the role of hypoxia-inducible factor-1α (HIF-1α) in arsenite-induced epithelial-mesenchymal transition (EMT) and malignant transformation of human liver epithelial cells (L-02 cells). Methods: After the L-02 cells were chronic treated with 2.0 µmol/L NaAsO(2) for 0 (reference), 10, 20, or 30 passages, con siRNA or HIF-1α siRNA was transfected into arsenite-transformed L-02 (T-L-02) cells by lipofectamine(TM)2000 and were set as T-L-02+con siRNA group and T-L-02+HIF-1α siRNA group as well as L-02 group and T-L-02 group, EMT index and levels of HIF-1α were detected by western blots. The reporter assays were performed to determine if HIF-1α directly regulate Snail transcriptional activity, and soft agar colony formation and Transwell assay were used to detect the malignancy, invasion, and migration ability of cells. Results: When L-02 cells were treated for 10 generations with 2 µmol/L NaAsO(2), relative expressions of E-cadherin were gradually increased compared to control cells, while the levels of N-cadherin, Snail, and HIF-1α were gradually increased in the L-02 cells compared to control cells, showing the longer the treatment time was, the more obvious the change was (P<0.05) . Down regulating the level of HIF-1α by siNRA caused E-cadherin levels to rise compared to T-L-02 group, while the levels of N-cadherin and Snail fall back compared to T-L-02 group (P<0.05) . Double luciferase reporter gene assays showed that HIF-1α directly targeted Snail to regulate its expression. Soft agar colony formation and Transwell assays showed that the numbers of formed colonies, invasion cells, and metastasis cells of cells in T-L-02 group were all lower than those in L-02 group (P<0.05) . Conclusion: HIF-1α is involved in arsenite-induced EMT and malignant transformation of human liver epithelial cells via regulating Snail.

[Prognostic significance of early phase donor chimerism after allogeneic peripheral blood stem cell transplantation].

Objective: To evaluate the prognostic significance of early phase full donor chimerism (FDC) after myeloablative allogeneic peripheral blood stem cell transplantation (allo-PBSCT). Methods: The clinical data of 72 hematological patients received myeloablative allo-PBSCT from Feb. 2016 to Jul. 2017 were analyzed retrospectively. The median age was 36.5 years (range 4-59), 44 were males and 28 females. Of the donors, there were 35 HLA matched sibling donors, 27 haploidentical donors and 10 unrelated donors. Polymerase chain reaction amplification of short tandem repeat sequence (PCR-STR) was used to detect donor cell chimerism (DC) rate of recipient bone marrow at one, two and three months after transplantation. Results: The median follow-up was 462 d (range: 47-805 d), 55 cases were still alive, and 45 cases were disease-free survival (DFS) at the end of follow-up. The 2-year overall survival (OS) and DFS were (68.9±7.7)% and (59.5±6.3)%, respectively. A number of 16 cases underwent relapses, with 2-year cumulative incidence of (24.1±5.3)%. The median time of recurrence was 157(32-374) d. Forty cases (55.6%) developed acute graft-versus-host diseases (aGVHD), with median time of 35.5 (13-90) d. Chronic GVHD (cGVHD) occurred in 23 patients (31.9%), with median time of 169 (94-475) d. Univariate analysis found the following factors were not related to OS, DFS or relapse rate (RR), including age, sex, blood type and sex of donor-recipient, occurrence of aGVHD and cGVHD. The OS and DFS in cases reached FDC and no FDC at two months after transplantation were (85.2±6.9)% vs (66.1±7.7)% (P=0.051) and (76.7±7.7)% vs (48.9±8.1)% (P=0.021), respectively. The RR rate in FDC group was lower than that in no FDC group [(16.6±6.8)% vs (30.4±7.8)%, P=0.187, respectively]. Conclusion: The present study confirmed the important value for predicting the prognosis with whether or not the patients reached FDC at the early phase after allo-PBSCT. The OS and DFS in cases with FDC at two months after transplantation were significantly higher than those of no FDC patients.

Expressions and effects of G250, Bax and Bcl-2 in rats with renal clear cell carcinoma.

OBJECTIVE: To investigate the expressions and effects of G250, B-cell lymphoma-2 associated X protein (Bax) and Bcl-2 in rats with renal clear cell carcinoma (RCCC). MATERIALS AND METHODS: A total of 66 male Sprague-Dawley (SD) rats were selected, among which 56 were selected to establish RCCC rat model and the remaining 10 were selected as control group. Three weeks after modeling, 4 rats failed in the modeling. Expressions of G250 in RCCC rat model group and healthy rat model control group were detected by Reverse Transcription-Polymerase Chain Reaction (RT-PCR); expressions of Bcl-2 and Bax in each group were detected by Western blot and their effects were analyzed. RESULTS: The positive expression rates of G250 in 52 RCCC rats in model group and 10 healthy rats in control group were 83.3% and 0%, respectively. The results showed that expression of G250 had a certain correlation with the pathological changes of RCCC (p < 0.01). Expressions of Bax and Bcl-2 were up-regulated in the RCCC group, while expressions were down-regulated in the healthy control group (p < 0.05). CONCLUSIONS: G250, as a new specific marker of renal cell carcinoma, is involved in the pathological changes of renal cell carcinoma. Joint detection of Bax and Bcl-2 can be used as an important index for the diagnosis of RCCC.

Radiation pneumonitis in non-small-cell lung cancer patients treated with helical tomotherapy.

OBJECTIVE: In this study, we investigated the incidence of radiation pneumonitis (RP) in non-small-cell lung cancer (NSCLC) patients undergoing helical tomotherapy (HT) and the clinical and dosimetric factors associated with it. MATERIALS AND METHODS: We analyzed data from the treatment protocols of 62 NSCLC patients. The median total radiation dose was 64 Gy (range 57.6-66 Gy) at 1.8-2.2 Gy/fraction. Thirty-four of these patients underwent HT alone and 28 underwent HT in combination with chemotherapy. Treatment-related pneumonitis was graded according to the Common Terminology Criteria for Adverse Events, version 3.0. RESULTS: We found that RP grades 1, 2, 3 and 5 occurred in 29 (46.8%), 23 (37.1%), 8 (12.9%), and 2 (3.2%) patients, respectively. Using univariate analyses, we found that a grade ≥3 RP was associated with poor performance status (PS), age, planning target volume, mean lung dose, and relative V5through V25, in increments of 5 Gy (P < 0.005). We determined that PS and V5V15were the most significant factors associated with grade ≥3 RP using multivariate analysis. CONCLUSIONS: We found that poor PS and V5-V15 were the risk factors associated with grade ≥3 RP in NSCLC patients treated with HT. Thus, for NSCLC patients treated with HT, the volume of total lung with low-dose region (V5-V15) should be carefully regulated and the use of HT should be restricted in patients with Eastern Cooperative Oncology Group ≥2.

Optimization of candidate proteins for serological screening of Chlamydia trachomatis infection.

The aim of this study was to optimize candidate antigen proteins for serological screening of Chlamydia trachomatis infection. C. trachomatis positive serum and swabs of genital secretions were collected from 50 patients in the Tianjin Medical University General Hospital, as well as from 30 patients negative for C. trachomatis. Samples were assessed by colloidal gold assay in a sexually transmitted disease clinic as follows: serum antibodies for eight kinds of C. trachomatis immunodominant proteins (Pgp3, CPAF, CT143, CT101, CT694, CT875, CT813, and IncA) were detected, and two traditional gold standards, immunofluorescence and C. trachomatis cell culture of genital secretions, were used for comparison in order to determine the antigen protein combinations with the highest sensitivity and specificity. Of the 50 samples that tested positive for C. trachomatis infection by colloidal gold assay, 44 tested positive by micro-immunofluorescence, whereas 6 tested negative. In contrast, 14 samples tested positive by cell culture, whereas 36 tested negative. Serological results of the immunodominant protein combination of Pgp3, CT694, and CT875 shared positive coincidence rates of 97.73 and 92.86% with C. trachomatis micro-immunofluorescence and cell culture, respectively. No antibodies of the three proteins were detected in the 30 C. trachomatis samples that tested negative by colloidal gold assay; these samples also tested negative in C. trachomatis genital secretion culture. Overall, the combination of the three immunodominant proteins Pgp3, CT694, and CT875 had good sensitivity and specificity for serological screening of C. trachomatis infection, and the process was simple and easy to apply.

Secreted protein acidic and rich in cysteine expression in human colorectal cancer predicts postoperative prognosis.

OBJECTIVE: Secreted protein acidic and rich in cysteine (SPARC) is an extracellular matrix glycoprotein involved in cell proliferation, migration and angiogenesis. The aim of this study was to assess its expression in colorectal cancer, see whether and how it correlates with clinicopathological features, and evaluate its potential prognostic significance. PATIENTS AND METHODS: SPARC expression was detected by microarrays containing 847 immunohistochemically stained specimens, and further correlated with the clinicopathological and prognostic data. The prognostic significance of its expression was assessed using Kaplan-Meier survival with log-rank tests. Multivariate regression utilizing Cox's proportional hazard model was used to evaluate prognostic factors. RESULTS: SPARC expression in the normal colorectal mucosa and colorectal cancer tissue was significantly different (p < 0.001). Low SPARC expression was found to be associated with poor prognosis, and it was unfavorably correlated with overall survival and disease-free survival in colorectal cancer patients. In addition, SPARC expression in surrounding mesenchymal and stromal cells, bowel wall invasion, lymph node metastasis, and distant metastasis were independent prognostic factors for overall survival and disease-free survival. CONCLUSIONS: Reduced expression of SPARC in colorectal cancer tissue is associated with poor prognosis and aggressive clinicopathological features. Therefore, SPARC expression could potentially be used as a prognostic predictor for colorectal cancer patients.

Rapid genomic DNA changes in allotetraploid fish hybrids.

Rapid genomic change has been demonstrated in several allopolyploid plant systems; however, few studies focused on animals. We addressed this issue using an allotetraploid lineage (4nAT) of freshwater fish originally derived from the interspecific hybridization of red crucian carp (Carassius auratus red var., ♀, 2n=100) × common carp (Cyprinus carpio L., ♂, 2n=100). We constructed a bacterial artificial chromosome (BAC) library from allotetraploid hybrids in the 20th generation (F20) and sequenced 14 BAC clones representing a total of 592.126 kb, identified 11 functional genes and estimated the guanine-cytosine content (37.10%) and the proportion of repetitive elements (17.46%). The analysis of intron evolution using nine orthologous genes across a number of selected fish species detected a gain of 39 introns and a loss of 30 introns in the 4nAT lineage. A comparative study based on seven functional genes among 4nAT, diploid F1 hybrids (2nF1) (first generation of hybrids) and their original parents revealed that both hybrid types (2nF1 and 4nAT) not only inherited genomic DNA from their parents, but also demonstrated rapid genomic DNA changes (homoeologous recombination, parental DNA fragments loss and formation of novel genes). However, 4nAT presented more genomic variations compared with their parents than 2nF1. Interestingly, novel gene fragments were found for the iqca1 gene in both hybrid types. This study provided a preliminary genomic characterization of allotetraploid F20 hybrids and revealed evolutionary and functional genomic significance of allopolyploid animals.

First Report of Sweet Cherry Virescence Disease in China and Its Association with Infection by a 'Candidatus Phytoplasma ziziphi'-Related Strain.

Sweet cherry (Prunus avium L.) is a deciduous tree originating in the Black Sea/Caspian Sea region where Asia and Europe converge. Being highly valued for its timber and fruit, sweet cherry has been cultivated and naturalized on all continents. Over the past decade, the area of sweet cherry cultivation increased rapidly in China and has reached 140,000 ha. In April 2013, sweet cherry trees (cv. Summit) exhibiting floral virescence symptoms were observed in two orchards located in suburban Taian, Shandong Province, China. The diseased trees developed flowers having white petals with green veins or abnormal floral structures having cupped, green petals. The affected flowers failed to set fruit. A month following the first appearance of the virescence symptoms, the diseased trees became wilted and eventually died. Leaf and stem samples were collected from nine symptomatic and two nearby symptomless trees. Total DNA was extracted from each sample using the Plant Quick DNA Extract Kit (TianGen, Beijing, China). Nested-PCR was carried out using phytoplasma-universal primer pairs P1/P7 and R16F2n/R16R2 (1). All PCR assays with DNA templates from symptomatic samples yielded an amplicon of 1.25 kb, corresponding to the full-length F2nR2 region of phytoplasmal 16S rDNA. No amplicon was generated in PCRs containing DNA templates from symptomless plants. The amplicons were cloned into plasmid vector pMD18-T (TaKaRa, Dalian, China) and sequenced. The obtained sequences were nearly identical, and a representative sequence was deposited into GenBank (Accession No. KF268424). An analysis of the sequence through the iPhyClassifier (4) revealed that the sweet cherry virescence (SCV) disease was associated with infection by a phytoplasma closely related to the reference strain of 'Candidatus Phytoplasma ziziphi.' The 16S rDNA F2nR2 region of the SCV phytoplasma shared 99.8% nucleotide sequence identity with that of 'Candidatus Phytoplasma ziziphi' reference strain (Accession No. AB052876). A computer-simulated restriction fragment length polymorphism (RFLP) analysis of the SCV phytoplasma 16S rDNA F2nR2 sequence with a set 17 restriction enzymes (3) resulted in a collective RFLP profile identical to the reference pattern of the elm yellows phytoplasma group, subgroup B (16SrV-B). Phytoplasmal diseases of sweet cherry were reported previously in Europe and the etiological agents were phytoplasmas of other groups, including the aster yellows group (16SrI), the X-disease group (16SrIII), and the apple proliferation group (16SrX) (2). To our knowledge, this is the first report of a phytoplasmal disease of sweet cherry in China, and the SCV phytoplasma is a new member of the subgroup 16SrV-B. Presence of 16SrV-B phytoplasmas and their etiological association with various plant diseases in China have been reported previously; affected host plants included jujube, hemp fiber, paper mulberry, Chinese cherry, plum, apricot, red barberry, clover, dianthus, elm, and sunshine tree. Our identification of the SCV phytoplasma expands the known plant host range of the 16SrV-B phytoplasma lineage. The impact of the SCV phytoplasma in the regional ecosystem and in sweet cherry production is being assessed. References: (1) I. M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998. (2) S. Paltrinieri et al. Acta Hort. 550:365, 2001. (3) W. Wei et al. Int. J. Syst. Evol. Microbiol. 57:1855, 2007. (4) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.

Transferability of Newly Developed Pear SSR Markers to Other Rosaceae Species.

A set of 120 simple sequence repeats (SSRs) was developed from the newly assembled pear sequence and evaluated for polymorphisms in seven genotypes of pear from different genetic backgrounds. Of these, 67 (55.8 %) primer pairs produced polymorphic amplifications. Together, the 67 SSRs detected 277 alleles with an average of 4.13 per locus. Sequencing of the amplification products from randomly picked loci NAUPy31a and NAUpy53a verified the presence of the SSR loci. When the 67 primer pairs were tested on 96 individual members of eight species in the Rosaceae family, 61.2 % (41/67) of the tested SSRs successfully amplified a PCR product in at least one of the Rosaceae genera. The transferability from pear to different species varied from 58.2 % (apple) to 11.9 % (cherry). The ratio of transferability also reflected the closer relationships within Maloideae over Prunoideae. Two pear SSR markers, NAUpy43c and NAUpy55k, could distinguish the 20 different apple genotypes thoroughly, and UPGMA cluster analysis grouped them into three groups at the similarity level of 0.56. The high level of polymorphism and good transferability of pear SSRs to Rosaceae species indicate their promise for application to future molecular screening, map construction, and comparative genomic studies among pears and other Rosaceae species.

High prevalence of azithromycin resistance to Treponema pallidum in geographically different areas in China.

Treatment with effective antibiotics is one important strategy for syphilis control in China. This study aimed to evaluate the prevalence of azithromycin resistance to T. pallidum in China. A cross-sectional study was conducted among 391 patients with early syphilis recruited from STD clinics in eight cities during October 2008 and October 2011. The swabs were obtained from the moist lesions of the participating patients. A touchdown/nested PCR of the 23S ribosomal RNA (rRNA) gene was performed on DNA samples extracted from these specimens. The presence or absence of the A2058G point mutation, conferring resistance to azithromycin, was determined by restriction enzyme digestion analysis of the PCR amplicon by MboII. Two hundred and eleven patients with primary or secondary syphilis were found to have T. pallidum DNA in their moist lesions by PCR assays. The A2058G mutation was present in 91.9% (194/211, 95% CI, 87.2-95.1%) of these patients, with no significant differences noted between patients from the eastern part (93.8%), southern part (88.6%) and northern part (95.2%) of China (χ(2) = 2.303, p 0.316). Compared with patients who had not taken macrolides in previous years before study entry, the patients who had taken the antibiotics had a significantly higher prevalence of azithromycin resistance (97.0% vs. 62.5%), with an odds ratio of 19.65 (95% CI, 5.77-66.93). It can be concluded that prevalence of azithromycin resistance is substantial in China and consequently that the macrolides should not be used as a treatment option for early or incubating syphilis in China.

Effect analysis of 1-year posttransplant body mass index on chronic allograft nephropathy in renal recipients.

OBJECTIVE: We sought to evaluate the effects of body mass index (BMI) at 1 year after transplantation on chronic allograft nephropathy (CAN). METHODS: We grouped 564 kidney transplanted patients between June 1997 and March 2005 according to BMI at 1 year after transplantation: group I showed a BMI more than 18.5 and less than or equal to 25 (normal weight); group II, BMI greater than 25 and less than or equal to 30 (overweight); and group III, BMI greater than 30 (obese). We retrospectively studied all patients. All donors were living donors, none of whom were prisoners. RESULTS: One-year posttransplant BMI was greater than preoperative values in groups II and III (P < .05 and P < .01 respectively). The CAN incidences among the three groups were 34.9% (128/367), 38.4% (48/125), and 43.1% (31/72), respectively (group I vs III; P < .05). With the increase in 1-year posttransplant BMI the rates of hypertension, diabetes mellitus, and hyperlipidemia increased, but there was no difference in acute rejection episodes among the three groups. Multivariate analysis revealed BMI at the first postoperative year to show a significant influence on CAN. CONCLUSIONS: One-year BMI after kidney transplantation has a strong association with CAN. Thus diet control, exercise, and decreased immunosuppressive agent exposure may control BMI and decrease the incidence of CAN.

Mutations in 23S rRNA and ribosomal protein L4 account for resistance in Chlamydia trachomatis strains selected in vitro by macrolide passage.

Thirteen strains of Chlamydia trachomatis were exposed to subinhibitory concentrations of erythromycin (0.5 microg ml(-1)), azithromycin (0.5 microg ml(-1)) and josamycin (0.04 microg ml(-1)) to select macrolide-resistant mutants with serial passages. The C. trachomatis mutants presented with low-level resistance to erythromycin, azithromycin and josamycin for which a 16-fold increase, a 16-fold increase and an 8-fold increase respectively in the minimal inhibitory concentration (MICs) for the mutant strains compared with the MIC for the susceptible strains were found. The results of chemosensitivity showed that josamycin had the highest susceptibility rate compared with erythromycin and azithromycin in the treatment of C. trachomatis. The ribosomal protein L4 and 23S rRNA genes of the susceptible and resistant strains of C. trachomatis were partially sequenced. A double mutation was found in ribosomal protein L4 of the mutants, leading to Pro109(CCG)-->Leu(CTG), and Pro151(CCG)-->Ala(GCC) (Escherichia coli numbering) in the corresponding protein, but these mutations were also found in parent strains. An investigation into the sequences of 23S rRNAs in the mutants revealed point mutations of A2057G, A2059G and T2611C (E. coli numbering). These results suggest that point mutations located in 23S rRNA were associated with macrolide resistance in C. trachomatis.