[Randomized controlled clinical trials of a quick screening model for symptomatic bacterascites for guided antibiotic therapy].

Objective: To investigate the clinical significance of a quick screening model for symptomatic bacterascites for guided antibiotic therapy. Methods: Data were collected prospectively from 24 cases of cirrhotic ascites who were newly admitted to Nanchang Ninth Hospital between September 2016 and February 2017. No clear indication for antibiotic treatment was used when the number of polymorphonuclear cells in ascites was <250 cells/mm3. A quick screening model for symptomatic bacterascites was determined by positivity and was randomly divided into the experimental (12 cases) and the control group (12 cases). The experimental group was given antibiotic treatment during the whole process, while the control group did not receive antibiotic treatment. The 10th day of treatment was the end point of the study. The treatment responses of the two groups were compared. The treatment response results were divided into three categories: complete response, partial response, and no response. The sum of complete and partial response rates was used to determine the response rate. The Mann-Whitney U test and Fisher's exact test were used to compare the treatment responses between groups. Results: The baseline conditions of gender, age, screening score, and disease severity were consistent between the two groups (P>0.05). On the 10th day of treatment, the number of complete responses between the experimental group and the control group was 1 to 0, the number of partial responses was 7 to 2, and the number of non-responses was 4 to 10, Z=-2.467, P=0.014. The response rate was significantly better in the experimental group than in the control group [66.7% (8/12) vs. 16.7% (2/12), P=0.036]. Conclusion: Guided antibiotic therapy is somehow important for the quick screening model for symptomatic bacterascites, and patients with cirrhotic ascites who test positive in this model can benefit from antibiotic therapy.

Inheritance and molecular mapping of new green bug resistance genes in wheat germ plasms derived from Aegilops tauschii.

Molecular mapping of genes for crop resistance to the green bug, Schizaphis graminum Rondani, will facilitate selection of green bug resistance in breeding through marker-assisted selection and provide information for map-based gene cloning. In the present study, microsatellite marker and deletion line analyses were used to map green bug resistance genes in five newly identified wheat germ plasms derived from Aegilops tauschii. Our results indicate that the Gb genes in these germ plasms are inherited as single dominant traits. Microsatellite markers X wmc 157 and X gdm 150 flank G bx 1 at 2.7 and 3.3 cM, respectively. Xwmc 671 is proximately linked to G ba, G bb, G bc and G bd at 34.3, 5.4, 13.7, 7.9 cM, respectively. X barc 53 is linked distally to G ba and G bb at 20.7 and 20.2 cM, respectively. X gdm 150 is distal to G bc at 17.9 cM, and X wmc 157 is distal to G bd at 1.9 cM. G bx 1, G ba, G bb, G bc, G bd and the previously characterized G bz are located in the distal 18% region of wheat chromosome 7 DL. G bd appears to be a new green bug resistance gene different from G bx 1 or G bz. G bx 1, G bz G ba, G bb, G bc and G bd are either allelic or linked to Gb 3.

Categories of resistance to greenbug (Homoptera: Aphididae) biotype K in wheat lines containing Aegilops tauschii genes.

The wheat lines (cultivars) 'Largo', 'TAM110', 'KS89WGRC4', and 'KSU97-85-3' conferring resistance to greenbug, Schizaphis graminum (Rondani), biotypes E, I, and K were evaluated to determine the categories of resistance in each line to greenbug biotype K. Our results indicated that Largo, TAM110, KS89WGRC4, and KSU97-85-3 expressed both antibiosis and tolerance to biotype K. Largo, KS89WGRC4, and KSU97-85-3, which express antixenosis to biotype I, did not demonstrate antixenosis to biotype K. The results indicate that the same wheat lines may possess different categories of resistance to different greenbug biotypes. A new cage procedure for measuring greenbug intrinsic rate of increase (r(m)) was developed, by using both drinking straw and petri dish cages, to improve the efficiency and accuracy of r(m)-based antibiosis measurements.

Genetic analysis and molecular mapping of a wheat gene conferring tolerance to the greenbug (Schizaphis graminum Rondani).

The greenbug, Schizaphis graminum (Rondani), is one of the major pests of wheat worldwide. The efficient utilization of wheat genes expressing resistance to greenbug infestation is highly dependent on a clear understanding of their relationships. The use of such genes will be further facilitated through the use of molecular markers linked to resistance genes. The present study involved several F(2) wheat populations derived from crosses between susceptible cultivars and resistant germplasm carrying different greenbug resistance genes. These populations were used to characterize the inheritance of a wheat gene ( Gbz) conferring tolerance to greenbug biotype I, to identify molecular markers linked to Gbz, and to investigate the relationship between Gbz and Gb3, a previously identified greenbug resistance gene. Our results indicated that Gbz is inherited as a single dominant gene. Microsatellite marker Xwmc157 is completely linked to Gbz, and Xbarc53 and Xgdm46 flank Gbz at distances of 5.1 and 9.5 cM, respectively. Selection of Gbz using marker Xwmc157 alone gives breeders 100% selection accuracy. Gbz may be placed in the distal region of the long arm of the wheat chromosome 7D. The results of allelism tests indicated that Gbz is either allelic or tightly linked to Gb3.

[Cloning and characterization of a chromosome-encoded catechol 2,3-dioxygenase gene from Pseudomonas aeruginosa ZD 4-3]. / Klonirovanie i kharakteristika gena katekhol-2,3-dioksigenazy, lokalizovannogo v khromosome Pseudomonas aeruginosa ZD 4-3.

Catechol 2,3-dioxygenase (C23O), one of extradiol-type dioxygenases cleaving the aromatic C-C bond at the meta-position of dihydroxylated aromatic substrates, catalyzes the conversion of catechol to 2-hydroxymuconic semialdehyde. Based on curing experiment, PCR identification, and Southern hybridization, the gene responsible for C23O was localized on a 3.5-kb EcoRI/BamHI fragment and cloned from P. aeruginosa ZD 4-3 able to degrade both single and bicyclic compounds via the meta-cleavage pathway. A complete nucleotide sequence analysis of the C23O revealed that it had one ORF, which showed a strong amino acid sequence similarity to the known C23Os of mesophilic gram-negative bacteria. The alignment analysis indicated that distinct difference existed between the C23O in this study and the 2,3-dihydroxybiphenyl dioxygenases cleaving bicyclic aromatic compounds. The heterogenous expression of the pheB gene in Escherichia coli BL21(DE3) demonstrated that this C23O possessed a meta-cleavage activity.