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Optimal stomatal regulation is important for plant adaptation to changing environmental conditions and for maintaining crop yield. The guard cell signal γ-aminobutyric acid (GABA) is produced from glutamate by glutamate decarboxylase (GAD) during a reaction that generates CO2 as a by-product. Here, we investigated a putative connection between GABA signalling and the more clearly defined CO2 signalling pathway in guard cells. The GABA-deficient mutant Arabidopsis lines gad2-1 , gad2-2 , and gad1/2/4/5 were examined for stomatal sensitivity to various CO2 concentrations. Our findings show a phenotypical discrepancy between the allelic mutant lines gad2-1 and gad2-2 —a weakened CO2 response in gad2-1 (GABI_474_E05) in contrast to a wild-type response in gad2-2 (SALK_028819) and gad1/2/4/5. Through transcriptomic and genomic investigation, we traced the response of gad2-1 to a deletion of full-length Mitogen-activated protein kinase 12 (MPK12) in the GABI-KAT line, thereafter renamed as gad2-1 *. Guard cell-specific complementation of MPK12 in gad2-1* restored the wild-type CO2 phenotype, which confirms the proposed importance of MPK12 in CO2 sensitivity. Additionally, we found that stomatal opening under low atmospheric CO2 occurs independently of the GABA-modulated opening channel ALUMINIUM-ACTIVATED MALATE TRANSPORTER 9 (ALMT9). Our results demonstrate that GABA has a role in modulating the rate of stomatal opening and closing, but not in response to CO2 per se. [ABSTRACT FROM AUTHOR]

We examine whether working conditions in charter schools and traditional public schools lead to different levels of job satisfaction among teachers. We distinguish among charter schools managed by for-profit education management organizations (EMOs) and non-profit charter management organizations (CMOs) and stand-alone charter schools. We investigate our research question using data from the School and Staffing Survey. We find that teachers in charter schools are less satisfied with their jobs than teachers in traditional public schools. We also find that teachers in EMO-managed schools appear less satisfied than those in stand-alone charter schools. Our analyses suggest that lower salaries and limited union memberships help drive these lower levels of satisfaction, particularly among stand-alone charter schools and charter schools managed by EMOs.

The transcription factor forkhead box protein O1 (FoxO1) is closely related to the occurrence and development of ovarian cancer (OC), however its role and molecular mechanisms remain unclear. Herein, we found that FoxO1 was highly expressed in clinical samples of OC patients and was significantly correlated with poor prognosis. FoxO1 knockdown inhibited the proliferation of OC cells in vitro and in vivo. ChIP‐seq combined with GEPIA2 and Kaplan–Meier database analysis showed that structural maintenance of chromosome 4 (SMC4) is a downstream target of FoxO1, and FoxO1 promotes SMC4 transcription by binding to its −1400/−1390 bp promoter. The high expression of SMC4 significantly blocked the tumor inhibition effect of FoxO1 knockdown. Furtherly, FoxO1 increased SMC4 mRNA abundance by transcriptionally activating methyltransferase‐like 14 (METTL14) and increasing SMC4 m6A methylation on its coding sequence region. The Cancer Genome Atlas dataset analysis confirmed a significant positive correlation between FoxO1, SMC4, and METTL14 expression in OC. In summary, this study revealed the molecular mechanisms of FoxO1 regulating SMC4 and established a clinical link between the expression of FoxO1/METTL14/SMC4 in the occurrence of OC, thus providing a potential diagnostic target and therapeutic strategy. [ABSTRACT FROM AUTHOR]

Tuberculosis, caused by Mycobacterium tuberculosis (Mtb), remains a global health crisis with substantial morbidity and mortality rates. Type II alveolar epithelial cells (AEC-II) play a critical role in the pulmonary immune response against Mtb infection by secreting effector molecules such as antimicrobial peptides (AMPs). Here, human β-defensin 1 (hBD1), an important AMP produced by AEC-II, has been demonstrated to exert potent anti-tuberculosis activity. HBD1 overexpression effectively inhibited Mtb proliferation in AEC-II, while mice lacking hBD1 exhibited susceptibility to Mtb and increased lung tissue inflammation. Mechanistically, in A549 cells infected with Mtb, STAT1 negatively regulated hBD1 transcription, while CEBPB was the primary transcription factor upregulating hBD1 expression. Furthermore, we revealed that the ERK1/2 signaling pathway activated by Mtb infection led to CEBPB phosphorylation and nuclear translocation, which subsequently promoted hBD1 expression. Our findings suggest that the ERK1/2-CEBPB-hBD1 regulatory axis can be a potential therapeutic target for anti-tuberculosis therapy aimed at enhancing the immune response of AEC-II cells. [ABSTRACT FROM AUTHOR]

We analyse a Neutron Star Interior Composition Explorer observation of the black hole X-ray binary MAXI J1820+070 during a transition from type-C to type-B quasi-periodic oscillations (QPOs). We find that below ∼2 keV, for the type-B QPOs the rms amplitude is lower and the magnitude of the phase lags is larger than for the type-C QPOs. Above that energy, the rms and phase-lag spectra of the type-B and type-C QPOs are consistent with being the same. We perform a joint fit of the time-averaged spectra of the source, and the rms and phase-lag spectra of the QPOs with the time-dependent Comptonization model vkompth to study the geometry of the corona during the transition. We find that the data can be well fitted with a model consisting of a small and a large corona that are physically connected. The sizes of the small and large coronae increase gradually during the type-C QPO phase whereas they decrease abruptly at the transition to type-B QPO. At the same time, the inner radius of the disc moves inward at the QPO transition. Combined with simultaneous radio observations showing that discrete jet ejections happen around the time of the QPO transition, we propose that a corona that expands horizontally during the type-C QPO phase, from ∼104 km (⁠|$\sim 800\, R_{\rm g}$|⁠) to 105 km (⁠|$\sim 8000\, R_{\rm g}$|⁠) overlying the accretion disc, transforms into a vertical jet-like corona extending over ∼104 km (⁠|$\sim 800\, R_{\rm g}$|⁠) during the type-B QPO phase. [ABSTRACT FROM AUTHOR]

MAXI J1348−630 is a low-mass X-ray black hole binary located in the Galaxy and undergone the X-ray outburst in 2019. We analysed the observation data in very soft state during the outburst between MJD 58588 and MJD 58596 based on the Insight - HXMT observations from 2 to 20 keV via the continuum fitting method to measure the spin of the stellar-mass black hole in MAXI J1348−630. The inner disc temperature and the apparent inner disc radius were found to be |$0.47\pm 0.01 \rm \,\rm \,keV$| and 5.33 ± 0.10  Rg from the observation data modeled by the multicolour disc blackbody model. Assuming the distance of the source |$D\sim 3.4 \rm \,kpc$| , the mass of the black hole M ∼ 11 M⊙, and the inclination of the system i ∼ 29.2°, the spin is determined to be a ⋆ = 0.41 ± 0.03 for fixing hardening factor at 1.6 and |$n_{H}=8.6\times 10^{21} \rm cm^{-2}$|. Besides, considering the uncertainty of the parameters D, M, i of this system, with the Monte Carlo analysis, we still confirm the moderate spin of the black hole as |$a_{\star }=0.42^{+0.13}_{-0.50}$|. Some spectral parameters (e.g. column density and hardening factor) which could affect the measurements of the BH spin are also briefly discussed. [ABSTRACT FROM AUTHOR]

Post-stroke depression (PSD), the most frequent psychiatric complication following stroke, could have a negative impact on the recuperation of stroke patients. Hyperhomocysteinemia (HHCY) has been reported to be a modifiable risk factor of stroke. The study tries to explore the effect of HHCY on PSD and the role of N-methyl-d-aspartate receptors (NMDARs)-mediated synaptic alterations. Forty-five adult male Sprague–Dawley rats were randomly allocated into five groups: sham operation group, middle cerebral artery occlusion group (MCAO), HCY-treated MCAO group HCY and MK-801 co-treated MCAO group and MK-801-treated MCAO group. 1.6 mg/kg/d D, L-HCY was administered by tail vein injection for 28 d prior to SHAM or MCAO operationand up to 14 d after surgery. The MK-801 (3 mg/kg) was administered by intraperitoneal injection 15 min prior to MCAO operation. HCY treatment aggravated depressive-like disorders of post-stroke rats by the open field test and sucrose preference test. Further, HCY significantly decreased central monoamines levels in the MCAO rats by HPLC. The transmission electron microscopy results showed that the number of synapses and the area of postsynaptic density decreased in the hippocampus of the HCY-treated MCAO rats. Additionally, HCY augmented ischemia-induced up-regulation of NMDARs, decreased the levels of synaptic structure-related marker PSD-95and the synaptic transmission-associated synaptic proteins (VGLUT1, SNAP-25 and Complexin Ι/ΙΙ). These effects of HCY were partly reversed by the NMDA antagonist MK-801. The current study suggested that NMDARs-mediated synaptic plasticity may be involved in the adverse effect of HCY on PSD. [ABSTRACT FROM AUTHOR]

Summary: Using microscopy to investigate stomatal behaviour is common in plant physiology research. Manual inspection and measurement of stomatal pore features is low throughput, relies upon expert knowledge to record stomatal features accurately, requires significant researcher time and investment, and can represent a significant bottleneck to research pipelines.To alleviate this, we introduce StomaAI (SAI): a reliable, user‐friendly and adaptable tool for stomatal pore and density measurements via the application of deep computer vision, which has been initially calibrated and deployed for the model plant Arabidopsis (dicot) and the crop plant barley (monocot grass).SAI is capable of producing measurements consistent with human experts and successfully reproduced conclusions of published datasets.SAI boosts the number of images that can be evaluated in a fraction of the time, so can obtain a more accurate representation of stomatal traits than is routine through manual measurement. An online demonstration of SAI is hosted at https://sai.aiml.team, and the full local application is publicly available for free on GitHub through https://github.com/xdynames/sai‐app. [ABSTRACT FROM AUTHOR]

Xiaoer Huanglong Granule is the only Chinese Patent Medicine widely used for treating attention deficit hyperactivity disorder. However, not much is known about the bioactive components and pharmacokinetics of Xiaoer Huanglong Granule even after it was successfully introduced into clinical use. This study analyzed the components in the medication and rat plasma after oral administration with the help of the UNIFI platform and Masslynx. A total of 119 and 37 components were detected in the medication and plasma, respectively, using an ultra‐performance liquid chromatography‐tandem mass spectrometer. We established a rapid and sensitive simultaneous determination of one triterpene saponin, three monoterpene glycosides, and three lignans in rat plasma by solid‐phase extraction. The determination was accomplished within 7.50 min via gradient elution. The values of the lower limit of quantitation were validated at 0.08 ng/ml for tenuifolin, 0.8 ng/ml for lactiflorin, 1.828 ng/ml for albiflorin, 2 ng/ml for paeoniflorin, gomisin B, and gomisin D, 10 ng/ml for schisandrin. The results from validations of other methods were all acceptable (relative standard deviation ≤ 14.94%). This is the first report on the identification and pharmacokinetics studies of components in Xiaoer Huanglong Granule. Moreover, the pharmacokinetic behavior of lactiflorin was studied for the first time. [ABSTRACT FROM AUTHOR]

Podocyte apoptosis is the common pathological basis for the progression of various kidney diseases. The overexpression of NOX4, a key enzyme involved in oxidative stress, has been proved to participate in the occurrence of podocyte apoptosis. Autophagy is a kind of adaptive response of cells under stress. However, as a "double-edged sword", the effect of autophagy on apoptosis in different cells and conditions is complex and variable, which has not been fully explained yet. Morroniside, extracted from the traditional medicinal plant Cornus officinalis , has remarkable antioxidant and anti-apoptosis effects, and has been proven to inhibit the overexpression of NOX4 in kidney tissue. Therefore, H2O2 was used in this study to explore the effects of autophagy on podocyte NOX4 overexpression and apoptosis induced by oxidative stress, as well as the protection mechanism of morroniside in podocytes. The results showed that the autophagy activator rapamycin, as well as the autophagy inhibitor chloroquine, could induce podocyte apoptosis cultured in normal condition, and chloroquine could also significantly increase the NOX4 expression. The NOX4 expression and apoptosis rate of podocytes increased after H2O2 treatment, the expression of LC3-II decreased, and the expressions of p62, mTOR, and p-mTOR increased. The intervention of morroniside and rapamycin improved autophagy activity and inhibited NOX4 overexpression and apoptosis induced by H2O2. And chloroquine reversed the inhibitory effect of morroniside on NOX4 overexpression and podocyte apoptosis. Taken together, our results suggest that the expression level of NOX4 in podocytes is regulated by autophagy activity. Morroniside can reduce oxidative stress induced podocyte apoptosis by restoring the damaged autophagy flux and inhibit the overexpression of NOX4. [ABSTRACT FROM AUTHOR]