Rectal sensitivity and associated factors in patients with different subtypes of functional defecation disorder.

OBJECTIVE: To investigate rectal sensitivity and associated factors in patients with different subtypes of functional defecation disorder (FDD). METHODS: We segregated individuals diagnosed with FDD into two groups based on their defecation patterns: those with dyssynergic defecation and those with inadequate defecatory propulsion. We gathered general information through questionnaires and assessed rectal sensitivity using anorectal manometry. The rectal sensitivity performances of the two groups were compared; the factors related to rectal sensitivity were analyzed to determine the factors associated with rectal sensitivity, and the effect of biofeedback therapy on rectal sensitivity was clarified. RESULTS: Rectal sensitivity in different subtypes of FDD decreased, and the difference between the two groups was not statistically significant ( P  > 0.05). There were no statistically significant differences in the first constant sensation volume, defecatory desire volume, and maximum tolerable volume between the different subtypes of FDD ( P  > 0.05). Multi-factor binary logistic regression analysis showed that age, constipation symptom score, and diabetes were all independent risk factors for decreased rectal sensitivity ( P  < 0.05). There were no statistically significant differences between the prior- and post-biofeedback therapy in the first constant sensation volume, defecatory desire volume, and maximum tolerable volume ( P  > 0.05). CONCLUSION: Rectal sensitivity in different subtypes of FDD decreased. Age, constipation symptom score, and diabetes were independent risk factors for decreased rectal sensitivity. Short-term biofeedback therapy did not improve rectal hyposensitivity in patients with FDD.

Evaluation of intra- and post-operative outcomes to compare robot-assisted surgery and conventional laparoscopy for gynecologic oncology.

OBJECTIVE: To compare robot-assisted surgery and conventional laparoscopy for gynecologic oncology regarding intra- and post-operative outcomes. METHODS: A retrospective study was performed on consecutive patients with gynecologic oncology from February 2014 to October 2017 at Gansu Provincial Hospital, China. Multivariable linear and logistic regression models were performed to explore the difference between two surgeries in the surgical outcomes after adjusting for potential confounders. RESULTS: 276 women were included in this study: 153 robot-assisted surgeries and 123 conventional laparoscopies. The multivariable linear regression model showed that robot-assisted surgery was longer operative time [coefficient (coef), 33.76; 95% CI, 12.47, 55.05; P = 0.002) ], higher lymph node yield (coef, 10.41; 95% CI, 7.47, 13.35; P < 0.001), shorter time to early post-operative feeding (coef, -1.09; 95% CI, -1.33, -0.84; P < 0.001) and less post-operative drainage volume (coef, -368.77; 95% CI, -542.46, -195.09; P < 0.001) than conventional laparoscopy. However, no difference was observed between the two surgeries regarding the estimated blood loss (P > 0.05). The multivariable logistic regression model showed that post-operative complications were similar between robot-assisted surgery and conventional laparoscopy (P > 0.05). CONCLUSION: Robot-assisted surgery was superior to conventional laparoscopy regarding intra- and post-operative outcomes for gynecologic oncology.

Identification and genetic mapping for rht-DM, a dominant dwarfing gene in mutant semi-dwarf maize using QTL-seq approach.

Semi-dwarfism is an agronomically important trait in breeding for stable high yields and for resistance to damage by wind and rain (lodging resistance). Many QTLs and genes causing dwarf phenotype have been found in maize. However, because of the yield loss associated with these QTLs and genes, they have been difficult to use in breeding for dwarf stature in maize. Therefore, it is important to find the new dwarfing genes or materials without undesirable characters. The objectives of this study were: (1) to figure out the inheritance of semi-dwarfism in mutants; (2) mapping dwarfing gene or QTL. Maize inbred lines '18599' and 'DM173', which is the dwarf mutant derived from the maize inbred line '173' through 60Co-γ ray irradiation. F2 and BC1F1 population were used for genetic analysis. Whole genome resequencing-based technology (QTL-seq) were performed to map dwarfing gene and figured out the SNP markers in predicted region using dwarf bulk and tall bulk from F2 population. Based on the polymorphic SNP markers from QTL-seq, we were fine-mapping the dwarfing gene using F2 population. In F2 population, 398 were dwarf plants and 135 were tall plants. Results of χ2 tests indicated that the ratio of dwarf plants to tall plants was fitted to 3:1 ratio. Furthermore, the χ2 tests of BC1F1 population showed that the ratio was fitted to 1:1 ratio. Based on QTL-seq, the dwarfing gene was located at the region from 111.07 to 124.56 Mb of chromosome 9, and we named it rht-DM. Using traditional QTL mapping with SNP markers, the rht-DM was narrowed down to 400 kb region between SNP-21 and SNP-24. The two SNPs were located at 0.43 and 0.11 cM. Segregation analysis of F2 and BC1F1 indicated that the dwarfing gene was likely a dominant gene. This dwarfing gene was located in the region between 115.02 and 115.42 Mb on chromosome 9.

Identification, Mapping, and Molecular Marker Development for Rgsr8.1: A New Quantitative Trait Locus Conferring Resistance to Gibberella Stalk Rot in Maize (Zea mays L.).

Maize stalk rot is a major fungal disease worldwide, and is difficult to control by chemical methods. Therefore, in maize breeding, quantitative trait loci (QTLs) conferring resistance are important for controlling the disease. Next-generation sequencing technologies are considered a rapid and efficient method to establish the association of agronomic traits with molecular markers or candidate genes. In the present study, we employed QTL-seq, which is a whole-genome resequencing-based approach, to identify candidate genomic regions conferring resistance to maize stalk rot. A novel resistance QTL Rgsr8.1 was finely mapped, conferring broad-spectrum resistance to Gibberella stalk rot (GSR). Segregation analysis in F2 and BC1F1 populations, which were derived from a cross between 18327 (Susceptible) and S72356 (Resistant), indicated that the resistance to GSR was likely to be a quantitatively inherited trait in maize. The result of QTL-seq showed that the resistance to GSR was mapped on chromosome 8 from 161.001 to 170.6 Mb. Based on the simple sequence repeat (SSR) markers, single-nucleotide polymorphism (SNP) markers, and the recombinant test, the location of Rgsr8.1 was narrowed down to 2.04 Mb, flanked by SSR-65 and SNP-25 markers at the physical location from 164.69 to 166.72 Mb based on the maize reference genome. In this region, two candidate resistant genes were found with, one auxin-responsive elements and the other encoding a disease resistance protein. In summary, these results will be useful in maize breeding programs to improve the resistance to GSR in maize.

[Identification of differentially expressed genes in rats and preliminary analysis in regression of vascular calcification].

OBJECTIVE: To investigate the differentially expressed genes in rat in the process of regression of vascular calcification by using the suppression subtractive hybridization (SSH). METHODS: 24 SD male rats which aged 6 weeks and specific pathogen free grade were selected and randomly divided into 3 groups (n = 8): control group, calcification group and regression group respectively. Vascular calcification model (vitamin D3 plus nicotine, VDN) were made from rats in calcification group and regression group, and rats in control group were intragastric administered with normal saline and lavaged with peanut oil. Rats were bred for 8 weeks in calcification group and control group, while rats in regression group were fed for 16 weeks. All rats were killed to measure concentration of calcium in the arterial tissue and examine the pathological lesion changes. Subtractive hybridization among vascular cDNA sequences from calcification group and regression group were established. The cDNA fragments which expressed higher or lower in regression group than those in calcification group were isolated. Differentially expressed genes with cDNA fragment were inserted into PMD18-T plasmid vector and transformed competent DH-5alpha, cDNA libraries of differentially expressed gene between calcification group and regression group were then constructed. Recombinant vectors were analyzed by colony PCR, positive genes were randomly selected for sequencing and analyzed by BLAST. 4 genes were randomly selected for RT-PCR certification combined with semi-quantitative analysis of DNA bands. RESULTS: VDN model of rats were successfully constructed. Concentration of tissue calcium in calcification group (15.34 mg/g +/- 2.51 mg/g) was significantly increased compared to that in control group (5.20 mg/g +/- 0.75 mg/g, P < 0.001), while in comparison with calcification group (15.34 mg/g +/- 2.51 mg/g), calcium in regression group was relatively lower (12.73 mg/g +/- 1.89 mg/g, P < 0.05). 28 up-regulated genes and 22 down-regulated genes were gained through sequencing and BLAST analysis among positive clones. RT-PCR validation indicated that 4 genes such as prdx3 and Ank2 had increasedly expressed in regression group than those in calcification group, the average fold change was 1.7. CONCLUSION: Rat vascular calcification tissue had characteristic of active regression. Genes in relation to pyrophosphoric acid synthesis, glutamate signal peptides, anti-oxidant and ant-apoptosis were up-regulated, at the same time many genes related to ossification and oxidation activity were down-regulated in the process of calcification regression. Increased expression of calcification suppressor genes accompanying decreased expression of calcification promoting genes might be the intrinsic mechanisms which initiated the active regression of calcified tissues.