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Heterosis is a promising approach to increase wheat yield from a limited planting area. In this study, a fine quality restorer line 99AR144-1 and three stable male sterile lines, AL18A, AL36A and AL20A, were assigned as male and female, respectively. Seeds of the wheat line 99AR144-1 and three male sterile lines were mixed according to different proportions and then planted at an experimental farm at the Xinjiang Academy of Agri- Reclamation Sciences from 2013 to 2016. When the mixed sowing ratios of combinations 2 (AL36A × 99AR144- 1) and 3 (AL20A × 99AR144-1) were 6 to 8%, the seed production yields were higher than the control; the yield of hybrid seed production increased by 98.8 and 19.9%, respectively. This increase was attributed to a rise in the outcrossing seed setting rate. Further, this study used the Xbarc-8 SSR (simple sequence repeat) molecular marker to identify the purity of blend hybrid seeds and establish a regression equation for hybrid seed purity testing. The coefficient of the regression equation were 0.9878 and 0.9689 respectively, which shows that the purity of hybrids can be accurately predicted by using this equation. This method can quickly and accurately identify the seed purity in mixed seed production.

Adding irinotecan to neoadjuvant chemoradiotherapy (nCRT) in locally advanced rectal cancer (LARC) increases the pathologic complete response (pCR) rate but brings more toxicities. Robust biomarkers to predict response to irinotecan-based nCRT are extremely necessary for selecting the right patients. Our previous study suggests that patient-derived tumor organoids (PDTOs) sensitivity to chemoradiotherapy matches patient responses. In this study, we investigated whether PDTOs sensitivity to irinotecan can predict complete response (CR) and survival. Eligible patients receiving irinotecan-based nCRT between April 5, 2017 and December 11, 2020 were enrolled in the training cohort (n = 91) for response prediction and survival analysis. Patients receiving nCRT between February 21, 2021 and September 17, 2021 were included in the validation cohort (n = 27). Predictive performances of irinotecan organoid size ratio (OSR) for CR or pCR were evaluated. The irinotecan-sensitive groups had higher response rates compared with the insensitive groups (training cohort: 71.8% vs 24.4%, P

e15598 Background: 5-FU-based regimens are the mainstay treatment for colorectal cancer. However, the limited response rate to 5-FU-based regimens hampered the increase in the treatment efficacy of locally advanced rectal cancer. During the drug screening in the rectal cancer organoid biobank (n = 106), we found out that more than half of the organoids that were resistant to 5-FU monotherapy and sensitive to irinotecan maintained sensitive status to the treatment of 5-FU combined with irinotecan (combination-sensitive), while a quite proportion of them turn to become remarkably resistant to 5-FU plus irinotecan (combination-resistant). Some studies suggested the mechanism of 5-FU-based resistance was associated with the activation of some oncogenic pathways. However, the mechanism of the addition of 5-FU promoting the resistance to irinotecan is still unclear. Methods: To investigate the relationship between the combination-resistant organoids and corresponding patient responses, we collected patient clinical responses and survival outcomes. RNA sequencing and ATAC sequencing were performed to identify differential genes and their enrichment pathways. Moreover, small molecule inhibitors were used to try to reverse the resistance induced by 5-FU. Results: Twenty-one organoids showed sensitivity to irinotecan and resistance to 5-FU. Among them, 8 organoids (38.1%) were combination-resistant and 13 organoids (61.9%) showed sensitivity to combination treatment. Combination-resistant organoids corresponding patients had worse pathologic tumor regression grades (pTRGs) distribution (8/8, 100% had TRGs of 2-3 versus 100% had TRGs of 0-1 in combination-sensitive patients; p < 0.05) and disease-free survival (DFS) rates (HR:11.57, 95% IC:1.025-130.5; p = 0.0047) than patients whose organoids were combination-sensitive. Combination-resistant organoids had higher expression of Ki-67 and CD44 and reduced cleaved-caspase 3 in the combination treatment group and 5-FU group compared with the irinotecan group and control. Furthermore, we identified hedgehog pathway activation after adding 5-FU to irinotecan in combination-resistant organoids through RNA sequencing and ATAC sequencing. GANT-61, an inhibitor of the hedgehog pathway, increased sensitivity to the combination of 5-FU and irinotecan in combination-resistant organoids. Conclusions: We found that organoids which are sensitive to irinotecan turn to become resistant to 5-FU combined with irinotecan. Moreover, corresponding patients had worse responses and a lower DFS rate. The hedgehog pathway is activated in these organoids after the addition of 5-FU to irinotecan, and GANT-61 could reverse the resistance caused by 5-FU. However, more organoid-associated trials with large-scale patients are warranted to reverse the 5-FU-based resistance in the future.

Conditional gene inactivation and restoration are powerful tools for studying gene functions in the nervous system and for modeling neuropsychiatric diseases. The combination of the two is necessary to interrogate specific cell types within defined developmental stages. However, very few methods and animal models have been developed for such purpose. Here we present a versatile method for conditional gene inactivation and in situ restoration through reversibly inverting a critical part of its endogenous genomic sequence by Cre- and Flp-mediated recombinations. Using this method, we generated a mouse model to manipulate Mecp2, an X-linked dosage-sensitive gene whose mutations cause Rett syndrome. Combined with multiple Cre- and Flp-expressing drivers and viral tools, we achieved efficient and reliable Mecp2 inactivation and restoration in the germline and several neuronal cell types, and demonstrated phenotypic reversal and prevention on cellular and behavioral levels in male mice. This study not only provides valuable tools and critical insights for Mecp2 and Rett syndrome, but also offers a generally applicable strategy to decipher other neurologic disorders. SIGNIFICANCE STATEMENT Studying neurodevelopment and modeling neurologic disorders rely on genetic tools, such as conditional gene regulation. We developed a new method to combine conditional gene inactivation and restoration on a single allele without disturbing endogenous expression pattern or dosage. We applied it to manipulate Mecp2, a gene residing on X chromosome whose malfunction leads to neurologic disease, including Rett syndrome. Our results demonstrated the efficiency, specificity, and versatility of this new method, provided valuable tools and critical insights for Mecp2 function and Rett syndrome research, and offered a generally applicable strategy to investigate other genes and genetic disorders.

Objective To explore and find a new method to treat hilar cholangiocarcinoma with deep jaundice assisted by Da Vinci robot. Methods A hilar cholangiocarcinoma patient of type Bismuch-Corlette IIIa was found with deep jaundice (total bilirubin: 635 µmol/L). On the first admission, we performed Da Vinci robotic surgery including drainage of left hepatic duct, dissection of right hepatic vessels (right portal vein and right hepatic artery), and placement of right-hepatic vascular control device. Three weeks later on the second admission when the jaundice disappeared we occluded right-hepatic vascular discontinuously for 6 days and then sustained later. On the third admission after 3 weeks of right-hepatic vascular control, the right hemihepatectomy was performed by Da Vinci robot for the second time. Results The future liver remnant after the right-hepatic vascular control increased from 35% to 47%. The volume of left lobe increased by 368 mL. When the total bilirubin and liver function were all normal, right hemihepatectomy was performed by Da Vinci robot 10 weeks after the first operation. The removal of atrophic right hepatic lobe with tumor in bile duct was found with no pathologic cancer remaining in the margin. The patient was followed up at our outpatient clinic every 3 months and no tumor recurrence occurs by now (1 y). Conclusions Under the Da Vinci robotic surgical system, a programmed treatment can be achieved: first, the hepatic vessels were controlled gradually together with biliary drainage, which results in liver's partial atrophy and compensatory hypertrophy in the other part. Then a radical hepatectomy could be achieved. Such programmed hepatectomy provides a new treatment for patients of hilar cholangiocarcinoma with deep jaundice who have the possibility of radical heptolobectomy.

To study the clinical value of intrahepatic injections of Highly Agglutinative Staphylococcin (HAS) in the interventional treatment of liver carcinomas.Under ultrasonic guidance, intrahepatic injections of HAS were administered in 22 cases of pathologically diagnosed liver carcinomas, 3 days, 7 days, 30 days, 3 months, 6 months, 9 months, and 12 months after microwave coagulation therapy. The dose of each injection was 2000U.Immunohistochemical staining of the sample from the tumor site after HAS administrations demonstrated a significant increase in the number of antitumor immune cells compared with that before the injections (p0.01) and an improvement in local immune status. One-year survival rate and recurrence rate, which were determined by Kaplan- Meier method, were 93.8% and 81.9% respectively.As a new route of administration, intrahepatic injections of HAS are a safe and effective procedure and deserves further clinical research and discussion.

High-molecular-weight glutenin (HMW-GS) and low-molecular-weight glutenin (LMW-GS) subunits play an important role in determining wheat quality. To clarify the contribution of each subunit/allele to processing quality, 25 near-isogenic lines with different HMW-GS and LMW-GS compositions grown at two locations during the 2010 cropping season were used to investigate the effects of allelic variation on milling parameters, mixograph properties, raw white Chinese noodle (RWCN) and northern style Chinese steamed bread (NSCSB) qualities. The results showed that Glu-B1 and Glu-B3 made a large contribution to determining mixograph properties and processing quality, respectively. Subunit pairs 17 + 18 and 5 + 10, and alleles Glu-A3b, Glu-A3d, Glu-B3g and Glu-D3f made significant contributions to mixograph properties and no significant difference was detected on most parameters of RWCN and NSCSB for the allelic variation of HMW-GS and LMW-GS. The allelic interactions among glutenin loci had significant effects on wheat quality. The line with 1, 17 + 18, 2 + 12, Glu-A3c, Glu-B3b, Glu-D3c associated with superior mixograph properties, the line with 1, 7 + 9, 2 + 12, Glu-A3c, Glu-B3d, Glu-D3c had superior viscoelasticity of RWCN, and the line with 1, 7 + 9, 2 + 12, Glu-A3e, Glu-B3b, Glu-D3c had the highest total score of NSCSB. These results provide useful information for genetic improvement of the qualities of traditional Chinese wheat products.

In higher plants, L-galactono-1,4-lactone dehydrogenase (GLDH) plays important roles in ascorbic acid (AsA) biosynthesis and assembly of respiration complex I. Here we report three homoeologous genes (TaGLDH-A1, -B1 and -D1) encoding common wheat GLDH isozymes and a unique allelic variant (TaGLDH-A1b) associated with enhanced drought tolerance. TaGLDH-A1, -B1 and -D1 were located on chromosomes 5A, 5B and 5D, respectively and their transcripts were found in multiple organs. The three homoeologs each conferred increased GLDH activity when ectopically expressed in tobacco. Decreasing TaGLDH expression in wheat significantly reduced GLDH activity and AsA content. TaGLDH-A1b differed from wild type allele TaGLDH-A1a by an in-frame deletion of three nucleotides. TaGLDH-A1b was biochemically less active than TaGLDH-A1a and the total GLDH activity levels were generally lower in the cultivars carrying TaGLDH-A1b relative to those with TaGLDH-A1a. Interestingly, TaGLDH-A1b cultivars showed stronger water deficiency tolerance than TaGLDH-A1a cultivars and TaGLDH-A1b co-segregated with decreased leaf water loss in a F2 population. Finally, TaGLDH-A1b cultivars generally exhibited smaller leaf stomatal aperture than TaGLDH-A1a varieties in control or water deficiency environments. Our work provides new information on GLDH genes and function in higher plants. TaGLDH-A1b is likely useful for further studying and improving wheat tolerance to drought stress.

Grain hardness plays an important role in determining both milling performance and quality of the end-use products produced from common or bread wheat. The objective of this study was to characterize allelic variations at the Pina and Pinb loci in Xinjiang wheat germplasm for further understanding the mechanisms involved in endosperm texture formation, and the status of grain texture in Chinese bread wheat. A total of 291 wheat cultivars, including 56 landraces, and 95 introduced and 140 locally improved cultivars, grown in Xinjiang, were used for SKCS measurement and molecular characterization. Among the harvested grain samples, 185 (63.6%), 40 (13.7%), and 66 (22.7%) were classified as hard, mixed and soft, respectively. Eight different genotypes for the Pina and Pinb loci were identified, including seven previously reported genotypes, viz., Pina-D1a/Pinb-D1a, Pina-D1a/Pinb-D1b, Pina-D1b/Pinb-D1a, Pina-D1a/Pinb-D1p, Pina-D1a/Pinb-D1q, Pina-D1a/Pinb-D1aa, Pina-D1a/Pinb-D1ab, and a novel Pinb allele, Pinb-D1ac. This new allele, detected in Kashibaipi (local landrace) and Red Star (from Russia) has a double mutation at the 257th (G to A substitution) and 382nd (C to T substitution) nucleotide positions of the coding region. Pina-D1b, Pinb-D1b, and Pinb-D1p were the most common alleles in Xinjiang wheat germplasm, with frequencies of 14.3%, 38.1% and 28.6% in hard textured landraces, 25.5%, 56.9% and 11.8% in hard introduced cultivars, and 24.8%, 47.8% and 26.5% in hard locally improved cultivars, respectively. The restriction enzymes ApaI, SapI, BstXI and SfaNI were used to identify Pinb-D1ab or Pinb-D1ac, Pinb-D1b, Pinb-D1e and Pinb-Dg, respectively, by digesting PCR products of the Pinb gene. The unique grain hardness distribution in Xinjiang bread wheat, as well as the CAPs markers for identification of the Pinb alleles provided useful information for breeding wheat cultivars with optimum grain textures.