This article assessed the genetic relationship and genetic diversity in Dioscorea alata. Twenty samples were examined to identify their original plants, and analyzed by ISSR markers. The results showed that 20 samples were classified into three different plants, such as D. alata, D. persimilis, and D. fordii. There was significant difference in genetic similarity coefficient between D. alata and D. persimi as well as D. fordii. There was distinct differences in D. alata, the genetic similarity coefficient was resulted from 0.672 9 to 0.990 7. With UPGMA clustering method, 16 samples of D. alata could be divided into 4 groups. After comparing samples with the phenotypic characteristics of original plants, it showed that the color and the number of tuber were the most important characteristics of judging the genetic relationship of D. alata. It is concluded that the genetic variation of Dioscorea spp is significant, especially the genetic diversity in D. alata were in a high level. This article supplied a molecular biologic support for distinguishing Dioscorea spp, and also provided basis for breeding of D. alata.
DNA, Plant ; genetics ; Dioscorea ; classification ; genetics ; Genetic Variation ; Phylogeny ; Repetitive Sequences, Nucleic Acid

Objective:To explore the clinical characteristics and outcomes of SARS-CoV-2 infection in kidney transplant recipients(KTRs)and examine the risk factors for severe/critical infection.Methods:A retrospective analysis was conducted for 208 adult KTRs diagnosed with SARS-CoV-2 infection between December 15, 2022, and March 15, 2023.They were assigned into two groups of mild/ordinary(n=168)and severe/critical(n=40)according to the severity of SARS-CoV-2 infection.Two groups were compared with regards to general profiles, status of baseline vaccination against COVID-19, transplant history, immunosuppressive regimens, comorbidities and treatment outcomes.For continuous variables, t or Mann-Whitney U test was utilized for comparing the inter-group differences.For categorical variables, chi-square or Fisher's exact test was employed.Bonferroni correction was applied for multiple comparisons when p value was ≤0.05.Logistic regression analysis of univariates and multivariates was conducted for identifying the risk factors for severe/critical infections.Results:The rates of hospitalization, severe illness, ICU admission, mechanical ventilation and mortality among 208 KTRs with COVID-19 were 27.4%(57/208), 19.2%(40/208), 3.4%(7/208), 5.3%(11/208)and 1.9%(4/208)respectively.Among 57 COVID-19 infected individuals, 43.9%(25/57)experienced bone marrow suppression with an incidence of anemia 36.8%(21/57)and thrombocytopenia 22.8%(13/57). The lowest counts of whole blood lymphocyte, CD4 + T lymphocyte and CD8 + T lymphocyte were 390.0(245.0, 615.0), 138.0(78.0, 293.5)and 180.0(94.7, 575.2)cells/μL respectively.The incidence of bacterial, cytomegaloviral, Pneumocystis jirovecii and other fungal infections after COVID-19 infection was 17.8%(37/208), 3.8%(8/208), 2.9%(6/208)and 2.9%(6/208)respectively.The severe/critical group had a higher incidence of other pathogen infections as compared to mild/ordinary group, including bacterial infections[62.5%(25/40)vs 7.1%(12/168), 95% CI: 47.5%~63.3%, P<0.001], cytomegaloviral infections[15.0%(6/40)vs 1.2%(2/168), 95% CI: 8.1%~19.5%, P=0.001], P.jirovecii infections[15%(6/40)vs 0(0/168), 95% CI: 9.4%~20.6%, P<0.001]and other fungal infections of Candida, Cryptococcus, Malassezia and Aspergillus fumigatus[15.0%(6/40)vs 0(0/168), 95% CI: 9.4%~20.6%, P<0.001]. The incidence of acute kidney injury(AKI)after COVID-19 infection was 13.5%(28/208)and severe/critical group had a higher incidence of AKI than mild/ordinary group[52.5%(21/40)vs 4.2%(7/168), 95% CI: 40.3% to 56.3%, P<0.001]. Univariate analysis showed that age( P=0.003), male gender( P=0.002), smoking history( P=0.012), coronary heart disease( P=0.011), diabetes mellitus( P=0.002), chronic renal insufficiency( P=0.001)and pulmonary disease history( P=0.001)were significantly different between severe/critical and mild/ordinary groups.Multivariate regression analysis revealed that comorbid chronic kidney disease( OR=3.34, 95% CI: 1.46-7.64, P=0.004)and a history of lung disease( OR=3.42, 95% CI: 1.49-7.87, P=0.004)were independent risk factors for severe/critical illness.Baseline vaccination rate against COVID-19 was 17.8%(37/208). Completion of baseline vaccination was associated with a lower risk of severe/critical COVID-19 infection( OR=0.28, 95% CI: 0.08-0.98, P=0.047). Conclusions:KTRs with severe/critical COVID-19 infections are more prone to multiple pathogen co-infections and the incidence of kidney function impairment after infection has remained relatively high.Histories of pulmonary and chronic kidney diseases are independent risk factors for severe/critical infections.Completion of baseline vaccination provides protection against severe/critical infections.

Objective To investigate the prevalence of Echinococcus infections in small rodents around human residential areas in Yushu City, Qinghai Province in 2023, so as to provide insights into precision echinococcosis control. Methods One or two quadrats, each measuring 50 m × 50 m, were randomly assigned in Shanglaxiu Township and Longbao Township, Yushu City, Qinghai Province on June 2023, respectively, and 300 plate-type mouse traps, each measuring 12.0 cm × 6.5 cm, were assigned in each quadrat. Small rodents were captured during the period between 10 : 00 and 18 : 00 each day for 4 days. Then, all captured small rodents were identified and dissected, and liver specimens with suspected Echinococcus infections were subjected to pathological examinations. The Echinococcus cytochrome c oxidase 1 (cox1) gene was amplified using PCR assay, and the sequence of the amplified product was aligned to that was recorded in the GenBank to characterize the parasite species. In addition, a phylogenetic tree of Echinococcus was generated based on the cox1 gene sequence using the neighbor-joining method. Results A total of 236 small rodents were captured in Shanglaxiu and Longbao townships, Yushu City, including 65 Qinghai voles and 51 plateau pikas in Shanglaxiu Township, and 62 Qinghai voles and 58 plateau pikas in Longbao Township, and there was no significant difference in the constituent ratio of small rodents between the two townships (χ² = 0.294, P > 0.05). Seven plateau pikas and 12 Qinghai voles were suspected to be infected with Echinococcus by dissection, and pathological examinations showed unclear structure of hepatic lobules and disordered hepatocyte arrangement in livers of small rodents suspected of Echinococcus infections. PCR assay identified E. shiquicus DNA in 7 Qinghai voles, which were all captured from Shanglaxiu Township. Phylogenetic analysis showed that the cox1 gene sequence of Echinococcus in small rodents was highly homologous to the E. shiquicus cox1 gene sequence reported previously. Conclusion Plateau pika and Qinghai vole were predominant small rodents around human residential areas in Yushu City, Qinghai Province in 2023, and E. shiquicus infection was detected in Qinghai voles.