Objective To construct and validate a risk prediction model for delayed healing of venous leg ulcer(VLU),so as to provide a reference basis for early identification of people at high risk of delayed healing.Methods Using a convenience sampling method,331 VLU patients attending vascular surgery departments in 2 tertiary A hospitals in Sichuan Province from January 2018 to December 2022 were selected as a modeling group and an internal validation group,and 112 patients admitted to another tertiary A hospital were selected as an external validation group.Risk factors for delayed healing in VLU patients were screened using univariate analysis,LASSO regression,and multivariate logistic regression analysis,and a risk prediction model was constructed using R software,and the predictive effects of the models were examined using the area under the receiver operating characteristic curve,the Hosmer-Lemeshow test,decision curve,and the bootstrap resampling for internal validation and spatial external validation were performed,respectively.Results The predictors that ultimately entered the prediction model were diabetes(OR=4.752),deep vein thrombosis(OR=4.104),lipodermatosclerosis(OR=5.405),ulcer recurrence(OR=3.239),and ankle mobility(OR=5.520).The model had good discrimination(AUC:0.819 for internal validation and 0.858 for external validation),calibration(Hosmer-Lemeshow test:χ2=13.517,P=0.095 for internal validation and χ2=3.375,P=0.909 for external validation)and clinical validity.Conclusion The model constructed in this study has good differentiation and calibration,and it can effectively predict people at high risk of delayed healing of VLU,which facilitates targeted clinical interventions to improve ulcer outcomes and reduce the risk of delayed ulcer healing.

Objective: To learn the epidemiological characteristics of coronavirus disease 2019(COVID-19)clusters in Nanning,Guangxi Province,so as to provide reference for the prevention and control of COVID-19. Methods: The data of COVID-19 clusters from January to February,2020 in Nanning were collected through the Public Emergency Response System of National CDC. Descriptive epidemiological analysis were conducted to analyze the time,space and population distribution, source of infection,transmission chain, ways of detection and the scale of clusters. Results: Eleven clusters were reported,with 36 confirmed cases and 293 exposed persons. The average attack rate was 12.29%. There were ten family clusters. The epidemic scale was small,with an average of 3.27 cases. The onset of cases peaked on January 23,while the reporting time was mainly from February 10 to February 18. The cases were distributed in two cities and one county. The attack rate of Qingxiu District and Xixiangtang District was 16.95%,which was higher than 5.17% of Mashan County(p<0.05). The recurrence rate of family contacts was 25.42%,which was higher than that of other ways of contacts(p<0.05). Of eleven clusters,nine were caused by imported cases or related cases;five developed secondary cases or above,and the median interval between the first and secondary cases was three days. Conclusions The COVID-19 clusters in Nanning occurred mainly in families with small scales and most were caused by imported cases. The majority of the cases were reported during mid February. The attack rate in urban areas was higher than that in rural areas.

Objective To analyze genetic characteristics of HIV isolated from men who have sex with men(MSM) in Beijing and predict the epidemic trend in this population.Methods All of the HIV gene sequences in our laboratory obtained from MSM in Beijing were used,which were aligned with all of the HIV gene sequences from MSM and other populations in China downloaded from Los Alamos HIV Database.Phylogenetic trees were constructed by using software PhyML 3.0,based on which the relationships of prevalent HIV strains between Beijing MSM and other populations in China were further explored.The evolution rate,the time of most recent common ancestor (tMRCA),the epidemic parameters,the reproductive number (R0) were calculated by using software BEAST to predict HIV evolution and epidemic characteristics.Results Multiple HIV subtypes,including subtype B,CRF01_AE and CRF07_BC,were found to be prevalent among MSM in Beijing.In ML tree constructed based on strains from the whole country,three clusters including B-1,CRF01_AE-1,and CRF01_AE-2 were found among the MSM in Beijing (accounting for 40％).At least three independent introduction of B 1 cluster strains into Beijing MSM were found,which were at March 1991 (July 1984-February 1997),January 1994 (January 1989-January 1998),April 1991 (August 1984-January 1996).For CRF01_AE strains,two clusters including CRF01_AE-1 and CRF01_AE-2 were introduced into the population at December 2000 (March 1998-January 2003) and December 2001 (January 2000-July 2003) respectively.The population epidemiology of HIV in Beijing MSM was reconstructed based on sequences.The CRF01_AE-1 cluster spread more quickly than the other two clusters,and the evolution rate was higher.Conclusion Multiple HIV subtypes were found prevalent among MSM in Beijing.Although subtype B strain was introduced into Beijing MSM earlier than CRF01_AE strain,CRF01_AE strain increased more quickly than subtype B strain.More research and control of the CRF01_AE prevalence will be helpful for prevention and control of HIV epidemic in MSM in Beijing.

BACKGROUND:Angiotensin-converting enzyme as a key enzyme of the renin-angiotensin system, through the degradation effects of substance P mechanism, is involved in the occurrence and development of Alzheimer’s disease.
OBJECTIVE:To research the relationship between angiotensin-converting enzyme gene polymorphism and Alzheimer’s disease in Jiamusi region, as wel as the effect of gender and hypertension on the relationship.
METHODS:This case-control study included 96 Alzheimer’s disease patients. Another 102 subjects served as controls coming from the same area and in the same environmental condition. DNA segments were amplified using PCR in 20 g/L agarose gel electrophoresis and observed under ultraviolet lamp. II, ID, DD genotypes and genotype frequencies were calculated for statistical analysis. On this basis, according to clinical data col ected, we investigated association of Alzheimer’s disease with hypertension and gender.
RESULTS AND CONCLUSION:There was significant difference between Alzheimer’s disease patients and controls in angiotensin-converting enzyme genotypes and al ele frequency. There was statistical y significant difference between Alzheimer’s patients with hypertension and controls in angiotensin-converting enzyme genotypes and al ele frequency. There was no statistical difference between Alzheimer’s disease patients with different genders and controls in angiotensin-converting enzyme genotypes and al ele frequency. These findings indicate that there are some relationships between angiotensin-converting enzyme polymorphism and Alzheimer’s disease. II genotype is a risk factor for Alzheimer’s disease, angiotensin-converting enzyme II genotype is a risk factor for Alzheimer’s disease with hypertension.

Neutralizing antibodies are considered to be an important protective parameter used in HIV-l vaccine evaluation.However,the exact role that neutralizing antibodies plays in controlling the disease progression of HIV-1 infected peoples is still undetermined.In this paper,we compared the protective function of the neutralizing antibody response in the plasma from LTNP and TP against clade B and clade C pseudoviruses.No difference in the neutralizing activities between the plasma from LTNP and TP was found,which was consistent with the most recent reports.In addition,no correlations between the titer or breadth and CD4+ or viral load in HIV-1 infected individuals were found.The protective roles played by neutralizing antibodies in controlling disease progression of HIV-1 infected people need to be considered in a new viewpoint.

OBJECTIVETo study the in vitro embryo culture of Epimedium wushanense and provide scientific basis for large scale production of tissue culture.

METHODCullus and buds were induced from embryo of E. wushanense on a MS medium supplemented with different 2,4-D,6-BA, NAA, IBA.

RESULTThe optimal compositions of medium that induced callus and buds from embryo were the MS medium supplemented with 2,4-D 2 mg x L(-1), IBA 2 mg x L(-1) and NAA 0.5 mg x L(-1) and the MS medium supplemented with IBA 2 mg x L(-1) and 6-BA 0.5 mg x L(-1), respectively. The optimum medium for callus differentiation was MS + 6-BA 1 mg x L(-1) + NAA 0.5 mg x L(-1) + IBA 1 mg x L(-1), and MS +6-BA 1.0 mg x L(-1) + NAA 0.5 mg x L(-1) for shoots proliferation.

CONCLUSIONUsing embryo as explants, the method of induction and culture of E. wushanense was established by the callus and buds, and the embryo of E. wushanense can be quickly propagated.

Culture Media ; Epimedium ; embryology ; Regeneration ; Tissue Culture Techniques

Objective To evaluate the antiretroviral therapy(ART),analyze the prevalence of resistance in rural areas,Henan,and explore the presence of minor resistant variants in pre-ART.Methods One hundred and forty-nine AIDS patients initiating ART were recruited and investigated at intervals of 6 months. Method of In-house developed by our laboratory for genotypjc resistance test was to analyze the occurrence of resistance among the failure of ART,and the allele-specific real.time PCR(ASPCR)was used to detect the minor resistant variants at the baseline samples once the resistance occurred.Results Vimlload significantly decreased among the patients who received ART(t=275,P=0.0001),but the absolute counts of CD4+T lymphocytes had no significant change(t=1.765 168,P=0.0852).Rate of resistance among the patients of treatment failure was 4.88%.The result of ASPCR in the survey of baseline showed that the minor resistant variants of M184V were detected in 7 patients and mutation K103N presented in 5 patients.Conclusion The primary drug-resistant straias in the untreated patients were found in Henan,and they might develop the dominant resistance strains and bring about the failure of ART.

ObjectiveTo evaluate the sensitivity and accuracy of an in-house detecting method of HIV-1 genotypic drug resistance system. MethodsTotally 130 serum specimens from Henan and Guangxi province were collected from April 2004 to October 2008 and tested in the Military HIV Testing Center of China. ViroSeqTM v2.0 (Abbott, Switzerland), a US FDA approved HIV genotypic drug resistance detecting system was utilized as the reference method. All the specimens were detected by the novel in-house method and the reference method to validate the difference in amplifying efficiency, drug resistance mutation detection and drug resistance report. ResultsConcerning the 14 850 known drug resistance mutation sites,14 752 (99. 3％ ) mutations can be detected by both of the two methods. Rates of concordance of detection in the regions of protease inhibitors-, reverse transcriptase inhibitors- and both two classes inhibitors-resistance were99.7％ ( Kappa =0. 909 9 , P ＜0. 01 ) , 99. 0％ (Kappa=0.952 1, P＜0. 01) and99.3％ (Kappa=0. 948 8, P ＜ 0. 01 ) respectively. Drug resistance reports from these two systems showed similar results (Kappa = 0. 637 4, P ＜ 0. 01 ). The in-house detecting system identified 34 novel mutations besides the ViroSeqTM drug resistance mutation database ( ViroSeqTM software v2. 7). Two mutations, V179F and K238T,had significant effect on HIV drug resistance. ConclusionsThe in-house genotyping system is an accurate,cost-effective method and has a high concordance with commercial ViroSeqTM genotyping system. Database from the in-house assay was superior to this of the ViroSeqTM assay.

OBJECTIVETo study the Arbuscular mycorrhizal (AM) formation progress and infection characteristics between tissue culture plantlets of Pinellia ternata and Glomus mosseae.

METHODThe tissue culture plantlets of P. ternata were inoculated with G. mosseae, the formation of AM were sampled and observed with microscopy by staining.

RESULT AND CONCLUSIONThe hyphae of G. mosseae began to penetrate the root epidermis after 10 days of inoculation. Lots of intracellular hyphae formed in cortex cells at the 15th day. Arbuscules started to form and there were some hyphae on the root at the 20th day. At the 25th day, many arbuscules formed and most as Arum type. Some arbuscles started to disintegrate at the 30th day, and a few of vesicles occurred. Lots of spores formed after 35 days. At the 40th day, some vesicles began to decline. The hand section showed that the intercellular hyphae gradually formed in intercellular space, and the hyphae branched in cortex cells and occupied most cell lumen finally. It is expounded that P. ternata and G. mosseae could recognize each other quickly and form a symbiont system.

Cell Culture Techniques ; Cells, Cultured ; Glomeromycota ; growth & development ; physiology ; Hyphae ; growth & development ; physiology ; Mycorrhizae ; growth & development ; physiology ; Pinellia ; cytology ; microbiology

Human Immunodeficiency Virus Type 1 exists in vivo as quasispecies, and one of the genome's characteristics is its diversity. During the antiretroviral therapy, drug resistance is the main obstacle to effective viral prevention. Understanding the molecular evolution process is fundamental to analyze the mechanism of drug resistance and develop a strategy to minimize resistance. Objective: The molecular evolution of drug resistance of one patient who had received reverse transcriptase inhibitors for a long time and had treatment which replaced Nevirapine with Indinavir was analyzed, with the aim of observing the drug resistance evolution pathway. Methods: The patient, XLF, was followed-up for six successive times. The viral populations were amplified and sequenced by single-genome amplification. All the sequences were submitted to the Stanford HIV Drug Resistance Database for the analysis of genotypic drug resistance. Results: 149 entire protease and 171 entire reverse transcriptase sequences were obtained from these samples, and all sequences were identified as subtype B. Before the patient received Indinavir, the viral population only had some polymorphisms in the protease sequences. After the patient began Indinavir treatment, the variants carrying polymorphisms declined while variants carrying the secondary mutation G73S gained the advantage. As therapy was prolonged, G73S was combined with M46I/L90M to form a resistance pattern M46I/G73S/L90M, which then became the dominant population. 97.9% of variants had the M46I/G73S/L90M pattern at XLF6. During the emergence of protease inhibitors resistance, reverse transcriptase inhibitors resistance maintained high levels. Conclusion: Indinavir- resistance evolution was observed by single-genome amplification. During the course of changing the regimen to incorporate Indinavir, the G73S mutation occurred and was combined with M46I/L90M.