[Evaluation of the diagnostic efficiency of three anti-Echinococcus antibody-based assays for the serodiagnosis of echinococcosis].

OBJECTIVE: To evaluate the efficiency of three Chinese commercial anti-Echinococcus antibody-based assays for the serodiagnosis of echinococcosis. METHODS: A total of 142 sera from cystic echinococcosis patients, 89 sera from alveolar echinococcosis and 39 sera from healthy controls were sampled, and detected by kits A (ELISA), B (ELISA) and C (colloidal gold immunoassay). The routine blood testing results and biochemical parameters were compared between the cystic and alveolar echinococcosis patients, and the associations of the absorbance (A value) of the serum specific antibody detected by A and B kits with the routine blood testing results and biochemical parameters were examined in echinococcosis patients. In addition, the performance of these three assays for the serodiagnosis of echinococcosis was evaluated. RESULTS: There were no significant differences between the cystic and alveolar echinococcosis patients in terms of the median white blood cell count (WBC), neutrophil count (NEU), monocyte count (MONO), basophil count (BASO), alanine aminotransferase concentration (ALT), aspirate aminotransferase concentration (AST), total bilirubin (TBIL), direct bilirubin (DBIL), indirect bilirubin (IBIL) (all P values > 0.05), and higher median lymphocyte count (LYM) and albumin levels (ALB) were detected in cystic echinococcosis patients than in alveolar echinococcosis patients (both P values < 0.05), while the median eosinophil count (EOS) was greater in the alveolar echinococcosis patients than in the cystic echinococcosis patients (P < 0.01). The A value of the serum specific antibody detected by kit A showed a linear positive correlation with WBC (rs = 0.153, P < 0.05) and EOS (rs = 0.174, P < 0.05), and a linear negative correlation with TBIL (rs = -0.134, P < 0.05) and IBIL (rs = -0.146, P < 0.05), while the A value of the serum specific antibody detected by kit B showed a linear positive correlation with WBC (rs = 0.257, P < 0.01), NEU (rs = 0.203, P < 0.01), MONO (rs = 0.159, P < 0.05), EOS (rs = 0.330, P < 0.01), ALT (rs = 0.171, P < 0.01) and AST (rs = 0.160, P < 0.05), and a linear negative correlation with ALB (rs = -0.168, P < 0.05). The overall coincidence rate, sensitivity, specificity, Youden's index and Kappa value of A, B and C kits were 86.30%, 69.63% and 91.48%; 84.42%, 64.94% and 92.21%; 97.44%, 97.44% and 87.18%; 0.82, 0.62 and 0.79; and 0.600, 0.337 and 0.750 for the diagnosis of echinococcosis, respectively. The overall coincidence rate, sensitivity, specificity and Youden's index of A, B and C kits were 84.54%, 64.64% and 71.82%; 80.99%, 55.63% and 68.31%; 97.44%, 97.44% and 87.18%; and 0.78, 0.53 and 0.56 for the diagnosis of cystic echinococcosis, respectively, while the overall coincidence rate, sensitivity, specificity and Youden's index of A, B and C kits were 92.19%, 85.16% and 85.16%; 89.89%, 79.78% and 84.27%; 97.44%, 97.44% and 87.18%; and 0.87, 0.77 and 0.72 for the diagnosis of alveolar echinococcosis, respectively. The C kit showed cross-reactions in the serodiagnosis of cystic echinococcosis and alveolar echinococcosis. There were no significant difference in the area under the receiver operating characteristic curve (ROC) between A and B kits for the diagnosis of echinococcosis (0.970 vs. 0.948, Z = 1.618, P > 0.05), and there was a high agreement between A and B kits in the diagnosis of echinococcosis (Kappa = 0.585, P < 0.01). CONCLUSIONS: The three commercial anti-Echinococcus antibody-based kits exhibit a higher serodiagnostic efficiency for alveolar echinococcosis than for cystic echinococcosis. The A kit shows a high sensitivity and specificity for the diagnosis of echinococcosis, and has a relatively stable diagnostic performance and fewer influencing factors, which is suitable for the pre-surgical preliminary diagnosis and post-surgical follow-up monitoring of serum anti-Echinococcus antibody, while the C kit shows a high sensitivity and specificity for the diagnosis of echinococcosis, and is easy to perform and high in reporting rate, which is feasible for initial screening of echinococcosis.

[Study on the molecular phylogeny of Echinococcus multilocularis in Qinghai Province].

OBJECTIVE: To amplify and sequence Coxl and Nadl genes in Echinococcus multilocularis isolates from Qinghai Province, and to create phylogenetic trees and molecular clocks, so as to provide evidence for estimating the evolutionary relationships and origins of E. multilocularis in Qinghai Province. METHODS: Twenty-two post-surgical specimens of patients with hepatic alveolar echinococcosis were sampled from Qinghai Provincial People's Hospital in 2017. The Coxl and Nadl genes were amplified from E. multilocularis samples and sequenced. Then, the gene sequences were aligned to the Coxl and Nadl genes of Echinococcus species in GenBank database. The intra-species variation was observed, and the phylogenetic tree and molecular clock were created. RESULTS: All E. multilocularis samples shared more than 99% genetic homology with the sequences of Coxl and Nadl genes from the E. multilocularis Asian strain in the GenBank database. A total of 6 genotypes were identified, including 2 isolates that had no 100% homology with the sequences of known genes in the GenBank database. Phylogenetic tree analysis revealed remarkable clustering of the E. multilocularis samples with the E. multilocularis Asian strain, and the E. multilocularis isolates from Qinghai Province were estimated to date back to 94 000 years ago by the molecular clock. CONCLUSIONS: The present study characterizes 6 E. multilocularis genotypes in Qinghai Province, including 2 novel genotypes. Asian strain is the predominant strain of E. multilocularis in Qinghai Province, and the E. multilocularis isolates from Qinghai Province date back to 94 000 years ago.

Effect of rainfall regime and slope on runoff in a gullied loess region on the Loess Plateau in China.

Runoff was measured from seven plots with different slopes nested in Tuanshangou catchment on the Loess Plateau to study effect of slopes on runoff in relation to rainfall regimes. Based on nine years of field observation and K-mean clusters, 84 rainfall events were grouped into three rainfall regimes. Rainfall regime A is the group of events with strong rainfall intensity, high frequency, and short duration. Rainfall regime C consists of events with low intensity, long duration, and infrequent occurrence. Rainfall regime B is the aggregation of events of medium intensity and medium duration, and less frequent occurrence. The following results were found: (1) Different from traditional studies, runoff coefficient neither decreased nor increased, but presented peak value on the slope surfaces; (2) For individual plot, runoff coefficients induced by rainfall regime A were the highest, and those induced by rainfall regime C were the lowest; Downslope, the runoff coefficients induced by three rainfall regimes presented the same changing trend, although the peak value induced by regime A occurred on a shorter slope length compared to those by regime B and C; (3) Scale effect on runoff induced by rainfall regime A was the least, and that induced by rainfall regime C was the largest. These results can be explained by the interactions of crusting, soil moisture content, slope length and gradient, and erosion units, etc., in the context of different rainfall regimes.

Plant regeneration from in vitro-cultured seedling leaf protoplasts of Actinidia eriantha Benth.

Newly expanded in vitro leaves of Actinidia eriantha were used for protoplast isolation. Protoplasts were cultured in liquid MS medium (lacking NH4NO3) supplemented with 2,4-D (2,4-dichlorophenoxyacetic acid) and 0.4 M glucose. The plating efficiency after 3 weeks of culture was 19.4%, and calli were recovered without addition of fresh medium. These calli regenerated shoots on transfer to MS medium containing 2.28 µM zeatin and 0.57 µM IAA (indole-3-acetic acid). Regenerated shoots were rooted by immersion in 20 ppm IBA (indole-3-butyric acid) solution before culturing on half-strength MS medium lacking growth regulators. Somaclonal variation, in terms of chromosome number and nuclei per cell of protoplast-derived plants, was estimated.