Although a loss of healthy pollen grains induced by metabolic heat responses has been indicated to be a major cause of heat-induced spikelet sterility under global climate change, to date detailed ...information at pollen level has been lacking due to the technical limitations. In this study, we used picolitre pressure-probe-electrospray-ionization mass spectrometry (picoPPESI-MS) to directly determine the metabolites in heat-treated single mature pollen grains in two cultivars, heat-tolerant cultivar, N22 and heat-sensitive cultivar, Koshihikari. Heat-induced spikelet fertility in N22 and Koshihikari was 90.0% and 46.8%, respectively. While no treatment difference in in vitro pollen viability was observed in each cultivar, contrasting varietal differences in phosphatidylinositol (PI)(34:3) have been detected in mature pollen, together with other 106 metabolites. Greater PI content was detected in N22 pollen regardless of the treatment, but not for Koshihikari pollen. In contrast, there was little detection for phosphoinositide in the single mature pollen grains in both cultivars. Our findings indicate that picoPPESI-MS analysis can efficiently identify the metabolites in intact single pollen. Since PI is a precursor of phosphoinositide that induces multiple signaling for pollen germination and tube growth, the active synthesis of PI(34:3) prior to germination may be closely associated with sustaining spikelet fertility even at high temperatures.
Rice (Oryza sativa L.) plants grown in southwestern Japan are subjected to large variations in air temperature and solar radiation during the rainy season which can affect their growth. Therefore, in ...this study, a novel nitrogen (N) application method for topdressing was proposed to increase grain yield under different weather conditions. Field experiments were conducted to determine the grain yield response to the soil and plant analyzer development (SPAD) readings and normalized difference vegetation index (NDVI) during the early reproductive stage in 2018 and 2019. As the rainy season ended in early July in 2018 but continued until late July in 2019, the daily mean solar radiation during the vegetative and early reproductive stages was 26% lower in 2019 than in 2018. Grain yield was 10% lower in 2019 than in 2018, mainly due to the lower number of spikelets. During the early reproductive stage, the SPAD readings and NDVI were higher in 2019 than in 2018, suggesting that the biomass and N concentration in 2019 were lower and higher than those in 2018, respectively. Statistical modeling examination of grain yield response to growth‐related factors revealed that the N application rate during the reproductive stage and SPAD readings were significant predictors in 2018, whereas the N application rate and NDVI were significant predictors in 2019. Our findings suggest that SPAD readings and NDVI are key factors for determining N application rate during the reproductive stage under higher and lower solar radiation conditions during the vegetative and reproductive stages, respectively.
Toll like receptors (TLR) play important roles in the signaling of many pathogen‐related molecules and endogenous proteins associated with immune activation. The –196 to –174del polymorphism affects ...the TLR2 gene and alters its promoter activity. We investigated the influence of the TLR2–196 to –174del polymorphism on the occurrence of non‐cardiac gastric cancer (NCGC) in a Japanese population. The study was carried out with 289 patients with NCGC, 309 non‐cancer patients with abdominal discomfort and 146 healthy controls. The –196 to –174del TLR2 polymorphism was investigated using the allele‐specific polymerase chain reaction method in all of the subjects. The –196 to –174del/del genotype of TLR2 showed a significantly higher frequency in NCGC patients than in healthy controls (adjusted odds ratio OR = 6.06; 95% confidence interval CI = 1.86–19.72). Similarly, the frequency of the –196 to –174del/del genotype was significantly higher among NCGC patients than in non‐cancer patients (adjusted OR = 2.02; 95% CI = 1.22–3.34). The same genotype was associated with an increased risk of both intestinal (OR = 2.00, 95% CI = 1.12–3.60) and diffuse‐type (OR = 2.05; 95% CI = 1.11–3.79) histopathology. There were no significant associations between TLR2 genotypes and tumor stage and anatomical location. Our data suggest that the –196 to –174del/del genotype of TLR2 may increase the risk of gastric cancer in the Japanese population. (Cancer Sci 2007; 98: 1790–1794)
High night temperature (HNT) often reduces yield in field crops. In rice, HNT during the ripening stage diminishes endosperm cell size, resulting in a considerable reduction in final kernel weight; ...however, little is known about the underlying mechanisms at cell level. In this study, we performed picolitre pressure-probe-electrospray-ionization mass spectrometry to directly determine metabolites in growing inner endosperm cells of intact seeds produced under HNT conditions, combining with
C feeding and water status measurements including in situ turgor assay. Microscopic observation in the inner zone suggested that approximately 24.2% of decrease in cell expansion rate occurred under HNT at early ripening stage, leading to a reduction in cell volume. It has been shown that HNT-treated plants were subjected to mild shoot water deficit at night and endosperm cell turgor was sustained by a decline in osmotic potential. Cell metabolomics also suggests that active solute accumulation was caused by a partial inhibition of wall and starch biosynthesis under HNT conditions. Because metabolites were detected in the single cells, it is concluded that a partial arrest of cell expansion observed in the inner endosperms was caused by osmotic adjustment at mild water deficit during HNT conditions.
The deterioration of pulmonary function, such as FEV1-decline, is strongly associated with poor prognosis in patients with chronic obstructive pulmonary disease (COPD). However, few investigations ...shed light on useful biomarkers for predicting the decline of pulmonary function. We evaluated whether thymus and activation-regulated chemokine (TARC), a Th2 inflammation marker, could predict rapid FEV1-decline in COPD patients.
We recruited 161 patients with stable COPD and performed pulmonary function test once every six months. At the time of registration, blood tests, including serum levels of TARC were performed. We assessed the correlation between changes in parameters of pulmonary function tests and serum levels of TARC. The rapid-decline in pulmonary function was determined using 25th percentile of change in FEV1 or FEV1 percent predicted (%FEV1) per year.
In the FEV1-rapid-decline group, the frequency of exacerbations, the degree of emphysema, and serum levels of TARC was higher than in the non-rapid-decline group. When using %FEV1 as a classifier instead of FEV1, age, the frequency of exacerbations, the degree of emphysema and serum levels of TARC in the rapid-decline group was significantly greater than those in the non-rapid-decline group. In univariate logistic regression analysis, TARC was the significant predictive factor for rapid-decline group. In multivariate analysis adjusted for emphysema, serum levels of TARC are independently significant predicting factors for the rapid-decline group.
TARC is an independent predictive biomarker for the rapid-decline in FEV1. Measuring serum TARC levels may help the management of COPD patients by predicting the risk of FEV1 decline.
In previous work, probe electrospray ionization/mass spectrometry (PESI/MS) and sheath-flow probe electrospray ionization/mass spectrometry (sfPESI/MS) were reported for the rapid and minimally ...invasive analysis of food. In this work, a modified version of sfPESI will be reported. The sample surface was pricked with an acupuncture needle inserted in the sfPESI probe that protruded from the terminus of the tip by 5 mm. The invasion depth of the needle into the sample was ∼1 mm. After sampling, the needle was retracted into the solvent-preloaded capillary with a protrusion length of 0.1-0.2 mm from the tip. A mass spectrum of the sample captured on the needle was obtained by applying a high voltage to the needle. This method could be applicable to profiling analyses of plants with the epicuticular wax covering on the surfaces that are difficult to analyze by sf-PESI. The on-site mass spectrometric analysis for a growing apricot in the field was performed to monitor the developing stage of the fruit.
Despite strong electrostatic repulsion, like-charged ions in aqueous solution can effectively attract each other via ion-water interactions. In this paper we investigate such an effective interaction ...of like-charged ions in water by using the 3D-RISM-SCF method (i.e., electronic structure theory combined with three-dimensional integral equation theory for molecular solvents). Free energy profiles are calculated at the CCSD(T) level for a series of molecular ions including guanidinium (Gdm(+)), alkyl-substituted ammonium, and aromatic amine cations. Polarizable continuum model (PCM) and mean-field QM/MM free energy calculations are also performed for comparison. The results show that the stability of like-charged ion pairs in aqueous solution is determined by a very subtle balance between interionic interactions (including dispersion and π-stacking interactions) and ionic solvation/hydrophobic effects and that the Gdm(+) ion has a rather favorable character for like-charge association among all the cations studied. Furthermore, we investigate the like-charge pairing in Arg-Ala-Arg and Lys-Ala-Lys tripeptides in water and show that the Arg-Arg pair has a contact free-energy minimum of about -6 kcal/mol. This result indicates that arginine pairing observed on protein surfaces and interfaces is stabilized considerably by solvation effects.
•High night temperature accelerates embryo development and chalky formation.•PicoPPESI-MS characterizes cell metabolites including glutathione and ascorbate redox states.•Control of glutathione redox ...state was associated with the enhanced embryo growth.
High night temperature (HNT) at the ripening stage severely affects both rice yield and quality. HNT accelerates embryo growth and chalky formation in the developing grains, accompanying with a diminishment of endosperm cell size. Although these responses may be physiologically interacted each other in the grains, what signals are involved in the accelerated embryo development remains undetermined. In this work, we have used picolitre pressure-probe electrospray-ionization mass spectrometry (picoPPESI-MS) to conduct single-cell metabolomics at several regions in HNT-treated grains, embryonic scutellum and outer endosperms in the basal (‘chalky region’ at maturation) and middle (‘translucent region’ at maturation as a reference) positions. Microscopic observations showed that HNT promoted cell expansion rate in the scutellum. When embryonic cell expansion rate reached the maximum, spatial differences in several metabolisms including ascorbate-glutathione (ASC-GSH) pathway and purine were detected, together with considerable sugar and amino acid accumulations in embryonic scutellum cells. There was no treatment difference in GSH content during active cell expansion in HNT-treated embryos, although an increase in GSH/GSSG ratio due to a reduction in oxidized glutathione (GSSG) content has been contrastingly observed. In the endosperms, greater ASC accumulation with a difference in ASC/dehydroascobic acid ratio has been also detected under HNT conditions. Since dormancy is often correlated with GSSG concentration, it is concluded that spatial regulation of GSH redox homeostasis detected at cell-level might be essential for dormancy alleviation and embryo growth accelerated in HNT-treated seeds.
Foehn-induced dry wind during the grain-filling stage induces shoot water deficit in rice (Oryza sativa L.) plants, which form a ring-shaped chalkiness in their endosperm that degrades milling ...quality and rice appearance. Air spaces formed in several inner cells cause significant transparency loss due to irregular light reflection. Although starch synthesis was suggested to be retarded by osmotic adjustment at foehn-induced moderately low water potential, the source of these air spaces remains unknown. We hypothesised that the preservation of vacuoles accompanied by a temporary reduction in starch biosynthesis in the inner cells leads to the chalky ring formation. Panicle water status measurement, light and transmission electron microscopic (TEM) observations, and an absolute qPCR analysis were conducted. Most starch synthesis-related genes exhibited temporarily reduced expression in the inner zone in accordance with the decrease in panicle water status. TEM observations provided evidence that vacuolar compartments remained among the loosely packed starch granules in the inner endosperm cells, where a chalky ring appeared after kernel dehydration. Taken together, we propose that vacuolar compartments sustained among the amyloplasts inadequately accumulated in rice endosperm cells and caused air space formation that leads to ring-shaped chalkiness under dry wind conditions.
Chest auscultation is commonly performed during respiratory physical therapy (RPT). However, the changes in breath sounds in children with atelectasis have not been previously reported. The aim of ...this study was to clarify the characteristics of breath sounds in children with atelectasis using acoustic measurements.
The subjects of this study were 13 children with right middle lobe atelectasis (3-7 years) and 14 healthy children (3-7 years). Lung sounds at the bilateral fifth intercostal spaces on the midclavicular line were recorded. The right-to-left ratio (R/L ratio) and the expiration to inspiration ratio (E/I ratio) of the breath sound sound pressure were calculated separately for three octave bands (100-200 Hz, 200-400 Hz, and 400-800 Hz). These data were then compared between the atelectasis and control groups. In addition, the same measurements were repeated after treatment, including RPT, in the atelectasis group.
Before treatment, the inspiratory R/L ratios for all the frequency bands were significantly lower in the atelectasis group than in the control group, and the E/I ratios for all the frequency bands were significantly higher in the atelectasis group than in the control group. After treatment, the inspiratory R/L ratios of the atelectasis group did not increase significantly, but the E/I ratios decreased for all the frequency bands and became similar to those of the control group.
Breath sound attenuation in the atelectatic area remained unchanged even after radiographical resolution, suggesting a continued decrease in local ventilation. On the other hand, the elevated E/I ratio for the atelectatic area was normalized after treatment. Therefore, the differences between inspiratory and expiration sound intensities may be an important marker of atelectatic improvement in children.