82 research outputs found
イネの根における塩排除効率のイオン種による差異
We investigated the exclusion rate of some ion species in order to discover the features of salt exclusion in rice roots. TSCF of each cation was negatively correlated with the transpiration rate as in the case of Na+. These results indicated that ion exclusion rates change with the transpiration rate. At the same transpiration rate, TSCF of IR28 was lower than that of KR1, which indicated that exclusion efficiency was essentially higher in IR28. The differences in TSCF of K+, Ca2+ and Mg2+ between both varieties were relatively small compared with those of Na+ and Li+. These results indicated that the difference in exclusion rate between varieties was affected by ion species. TSCF at the same transpiration rate seemed to be larger with the decrease in radius of hydrated ion. From these results, it was suggested that the exclusion system of Na+ in rice under saline conditions also works for K+, Li+, Ca2+ and Mg2+, and is driven by transpiration. It was also noted that exclusion may be affected by the radius of hydrated ion
A novel superior factor widely controlling the rice grain quality
Synthesis of storage starch and protein accumulation is the main action of endosperm organogenesis in term of the economic importance of rice. This event is strongly disturbed by abiotic stresses such as high temperature; thus, the upcoming global warming will cause a crisis with a great impact on food production^1,2^. The enzymes for the protein storage and starch synthesis pathway should work in concert to carry out the organogenesis of rice endosperm^3-5^, but the regulatory mechanism is largely unknown. Here we show that a novel regulatory factor, named OsCEO1, acts as the conductor of endosperm organogenesis during the rice grain filling stage. The physiological properties of _floury-endosperm-2_ (_flo2_) mutants showed many similarities to symptoms of grains developed under high-temperature conditions, suggesting important roles of the responsible gene in sensitivity to high-temperature stress. Our map-based cloning identified the responsible gene for the _flo2_ mutant, _OsCEO1_, which has no homology to any genes of known function. The _OsCEO1_ belongs to a novel conserved gene family and encodes a protein composed of 1,720 amino acid residues containing a TPR (tetratricopeptide repeat) motif, which is considered to mediate a protein-protein interaction. The yeast two-hybrid analysis raised an unknown protein showing homology to a late embryogenesis abundant protein and a putative basic helix-loop-helix protein as candidates for the direct interactor for _OsCEO1_, whereas no enzyme genes for the synthesis of storage substances were detected. The _flo2_ mutant exhibited reduced expression of several genes for putative regulatory proteins as well as many enzymes involved in storage starch and proteins. These results suggest that _OsCEO1_ is a superior conductor of the novel regulatory cascade of endosperm organogenesis and may have important roles in the response to high-temperature stress
Differential Expression of Vascular Endothelial Growth Factor (VEGF) and VEGF Receptors in the Sequence of Hyperplastic Polyp, Serrated Adenoma and Adenocarcinoma of Colorectum
AIM: The aim of this study was to investigate the role for vascular endothelial growth factor (VEGF) and its receptors, VEGFR-1 and -2, in the hyperplastic polyp (HP)- serrated adenoma (SA)-adenocarcinoma (AC) sequence of the colorectum.Methods: Thirty-six HPs, 33 SAs and 7 ACs (which contained HP and/or SA) were immunohistochemically examined for the expression of VEGF, VEGFR-1, and VEGFR-2.Results: VEGF protein was expressed in the cytoplasm of SA and AC tumor cells, and VEGFR-1 and VEGFR-2 were expressed both in the cytoplasm and on the membrane of these tumors, while there was faint or no expression of VEGF, VEGFR-1 and VEGFR-2 in HPs. Immunohistochemical staining revealed that 8.3% (3 of 36) HPs, 87.9% (29 of 33) SAs and 100% (7 of 7) ACs were positive for VEGF; 2.8% (1 of 36) HPs, 97.0% (32 of 33) SAs and 100% (7 of 7) ACs were positive for VEGFR-1; 16.7% (6 of 36) HPs, 100% (33 of 33) SAs and 100% (7 of 7) ACs were positive for VEGFR-2. The expression of VEGF, VEGFR-1 or VEGFR-2 was statistically correlated with the sequence of HP, SA and AC (P < 0.0001, respectively) Conclusion: Our results suggest that the VEGF pathway may play an important role in the HP-SA-AC sequence
Impact of COVID-19 infection on lung function and nutritional status amongst individuals with cystic fibrosis:A global cohort study
Background: Factors associated with severe COVID-19 infection have been identified; however, the impact of infection on longer-term outcomes is unclear. The objective of this study was to examine the impact of COVID-19 infection on the trajectory of lung function and nutritional status in people with cystic fibrosis (pwCF). Methods: This is a retrospective global cohort study of pwCF who had confirmed COVID-19 infection diagnosed between January 1, 2020 and December 31, 2021. Forced expiratory volume in one second percent predicted (ppFEV1) and body mass index (BMI) twelve months prior to and following a diagnosis of COVID-19 were recorded. Change in mean ppFEV1 and BMI were compared using a t-test. A linear mixed-effects model was used to estimate change over time and to compare the rate of change before and after infection. Results: A total of 6,500 cases of COVID-19 in pwCF from 33 countries were included for analysis. The mean difference in ppFEV1 pre- and post-infection was 1.4 %, (95 % CI 1.1, 1.7). In those not on modulators, the difference in rate of change pre- and post-infection was 1.34 %, (95 % CI -0.88, 3.56) per year (p = 0.24) and -0.74 % (-1.89, 0.41) per year (p = 0.21) for those on elexacaftor/tezacaftor/ivacaftor. No clinically significant change was noted in BMI or BMI percentile before and after COVID-19 infection. Conclusions: No clinically meaningful impact on lung function and BMI trajectory in the year following infection with COVID-19 was identified. This work highlights the ability of the global CF community to unify and address critical issues facing pwCF.</p
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