Effects of different phosphorus and potassium supply on the root architecture, phosphorus and potassium uptake, and utilization efficiency of hydroponic rice.

Phosphorus (P) and potassium (K) affect seedling growth, root configuration, and nutrient uptake in hydroponic rice, but there are few studies on all growth stages of rice. The purpose of this experiment was to determine the response characteristics of root morphology, plant physiology, and P and K uptake and utilization efficiency to different supplies of P and K. Two local conventional rice varieties (Shennong 265 and Liaojing 294) were used as experimental materials across four treatments, including HPHK (sufficient P and K supply), HPLK (sufficient P supply under low K levels), LPHK (sufficient K supply under low P levels) and LPLK (low P and K levels) in a hydroponic setting. The results showed that HPHK and HPLK significantly decreased the acid phosphatase activity of leaves and roots from full heading to filling stages when compared to LPHK and LPLK. Sufficient supply of P or K significantly increased the accumulation of P and K (aboveground, leaves, stem sheath, and whole plant) and root morphological parameters (root length, root surface area, total root volume, and tips) during major growth stages when compared to LP or LK levels. HPHK was significantly higher than other treatments in terms of dry weight and the root activity at the main growth stage, P and K uptake rates in nutrient solutions at various stages, related P and K efficiency at the maturity stage, yield, effective panicle number, and grain number per panicle. In addition, the effect of HPHK on the above indexes were significantly greater than those of single sufficient supply of P or K. In conclusion, HPHK can improve plant configuration, increase plant P and K absorption and root activity, and increase rice yield and related P and K utilization efficiency.

Analysis of Erect-Panicle Japonica Rice in Northern China: Yield, Quality Status, and Quality Improvement Directions.

China is the only country that extensively cultivates the indica and japonica rice varieties, with the largest japonica rice production area being in northeast China. A study of the relationship between the yield and quality of japonica rice and the effect of nitrogen fertilizer application on this relationship is important. In this paper, we aimed to assess the current yield and quality of japonica rice in northeast China. We selected erect-panicle varieties as the test materials. Field experiments were conducted using different nitrogen fertilizer levels for two consecutive years to analyze the rice varieties' yield, quality, interrelationship, and nitrogen fertilizer response. The average yield following high- and low-nitrogen treatments exceeded 10,000.00 kg/hm2, with a maximum of 12,285.63 kg/hm2. The high-yield-high-nitrogen treatment group had more panicles, a higher seed-setting rate, and a higher 1000-grain weight than the other groups. The high-yield-low-nitrogen group had a higher number of panicles and seed-setting rate than the other groups. The low-yield-high-nitrogen group had a lower number of whole grains, grain length-to-width ratio, and taste value than the other groups. The low-yield-low-nitrogen group had fewer primary branches than the other groups; excluding the primary branch-setting rate and 1000-grain weight, the values of the other panicle traits of the group were significantly higher than those of the other groups. The high-nitrogen-high-flavor group had lower panicle and spikelet numbers and higher spikelet fertility rates than the other groups. The low-nitrogen-high-flavor group had higher spikelet fertility rates and 1000-grain weight than the other groups. Compared to the other groups, the low-nitrogen-high-flavor group had a higher head rice yield, and the high-nitrogen-high-flavor group had a lower chalkiness rate. The main goal of the breeding and cultivation of high-yield and high-quality erect-panicle japonica rice in northern China is to achieve "dual high, dual low, and one high and one low" conditions, signifying a high yield with high or low nitrogen levels, low protein and amylose contents, high head rice rates, and low chalkiness. This study provides a new technique for enhancing the taste of northern erect-panicle japonica rice to promote the sustainable, high-yield, and high-quality development of japonica rice in northern China.

Effects of biochar application methods on greenhouse gas emission and nitrogen use efficiency in paddy fields.

Biochar application in rice production reduces nitrogen loss and greenhouse gases. We conducted in situ experiments for 3 years, with N210B0 (210 kg N ha-1) as the control. Two biochar application methods (B1:15 t ha-1 biochar applied once and B2: biochar applied three times at 5 t ha-1 yr-1) combined with two nitrogen levels (N210: 210 kg N ha-1 and N168: 168 kg N ha-1) were used. Soil physicochemical properties, CH4 and N2O emissions, functional gene abundance, rice yield, and nitrogen use efficiency were analyzed. Both methods improved the physicochemical properties of the soil, however, B1 was less effective than B2 in increasing soil pH, bulk density, organic carbon, total nitrogen, and microbial biomass nitrogen in year 3. B1 had a higher CH4 emission mitigation effect than B2 in 3 consecutive years, mainly due to the higher pmoA gene abundance. B1 showed a higher reduction effect of N2O emissions compared to B2 in year 1, but the opposite was observed in years 2 and 3. B2 had a higher abundance of AOB, nirK, and nosZ genes compared to B1 in year 3. Compared with N210B0, rice yields were increased by 9.1 %, 9.6 %, and 3.6 % with N210B1, N210B2, and N168B2, respectively, over 3 years, while N168B1 improved yields in the previous 2 years. Biochar improved nitrogen use efficiency over 3 consecutive years directly due to increased use efficiency of panicle fertilizer; the effect of B1 was greater than that of B2 during years 1 and 2, while the opposite was observed in year 3. Both Biochar applied once and three times appeared to be promising practices to increase yield and mitigate GHGs. From the GHGI perspective, the biochar applied once combined with 168 kg N ha-1 can further improve nitrogen use efficiency, and reduce GHGs without hindering improvements in rice yield.

Identification of novel key markers that are induced during traumatic brain injury in mice.

Background: Traumatic brain injury (TBI) has emerged as an increasing public health problem but has not been well studied, particularly the mechanisms of brain cellular behaviors during TBI. Methods: In this study, we established an ischemia/reperfusion (I/R) brain injury mice model using transient middle cerebral artery occlusion (tMCAO) strategy. After then, RNA-sequencing of frontal lobes was performed to screen key inducers during TBI. To further verify the selected genes, we collected peripheral blood mononuclear cells (PBMCs) from TBI patients within 24 h who attended intensive care unit (ICU) in the Affiliated Hospital of Yangzhou University and analyzed the genes expression using RT-qPCR. Finally, the receiver operator characteristic (ROC) curves and co-expression with cellular senescence markers were applied to evaluate the predictive value of the genes. Results: A total of six genes were screened out from the RNA-sequencing based on their novelty in TBI and implications in apoptosis and cellular senescence signaling. RT-qPCR analysis of PBMCs from patients showed the six genes were all up-regulated during TBI after comparing with healthy volunteers who attended the hospital for physical examination. The area under ROC (AUC) curves were all >0.7, and the co-expression scores of the six genes with senescence markers were all significantly positive. We thus identified TGM1, TGM2, ATF3, RCN3, ORAI1 and ITPR3 as novel key markers that are induced during TBI, and these markers may also serve as potential predictors for the progression of TBI.

The Use of Blended Teaching in Higher Medical Education during the Pandemic Era.

Objective: This study aims to compare the effect of blended teaching and traditional teaching in higher medical education during the pandemic era. Methods: Taking the teaching of neurology as an example, 293 Yangzhou University Clinical Medicine 2016 undergraduate students were selected as the research subjects, and were randomly divided into 2 groups a blended teaching group (n = 148) and a traditional teaching group (n = 145), and received blended teaching and traditional teaching, respectively. The blended teaching was based on a Massive Open Online Course, problem-based learning, and case-based learning and supplemented by Tencent video conferences, QQ messaging groups, and other auxiliary teaching tools. At the end of the course, the teaching effect and satisfaction rate were evaluated through theory assessment, practical skills assessment, and an anonymous questionnaire survey. Results: There were significant differences in theoretical achievements (81.83 ± 6.23 vs 76.79 ± 6.87, P < 0.001) and practical skill achievements (84.74 ± 6.50 vs 78.48 ± 6.53, P < 0.001). In addition, significant differences in all aspects of satisfaction rate were observed between the two groups (all P < 0.001). Conclusion: Blended teaching is beneficial to students' learning and stimulates their enthusiasm, cultivates clinical thinking ability, and improves teaching quality. Thus, it has played a positive role in the reform of higher medical teaching during the pandemic era.

Fe3O4 Nanozymes Improve Neuroblast Differentiation and Blood-Brain Barrier Integrity of the Hippocampal Dentate Gyrus in D-Galactose-Induced Aged Mice.

Aging is a process associated with blood-brain barrier (BBB) damage and the reduction in neurogenesis, and is the greatest known risk factor for neurodegenerative disorders. However, the effects of Fe3O4 nanozymes on neurogenesis have rarely been studied. This study examined the effects of Fe3O4 nanozymes on neuronal differentiation in the dentate gyrus (DG) and BBB integrity of D-galactose-induced aged mice. Long-term treatment with Fe3O4 nanozymes (10 µg/mL diluted in ddH2O daily) markedly increased the doublecortin (DCX) immunoreactivity and decreased BBB injury induced by D-galactose treatment. In addition, the decreases in the levels of antioxidant proteins including superoxide dismutase (SOD) and catalase as well as autophagy-related proteins such as Becin-1, LC3II/I, and Atg7 induced by D-galactose treatment were significantly ameliorated by Fe3O4 nanozymes in the DG of the mouse hippocampus. Furthermore, Fe3O4 nanozyme treatment showed an inhibitory effect against apoptosis in the hippocampus. In conclusion, Fe3O4 nanozymes can relieve neuroblast damage and promote neuroblast differentiation in the hippocampal DG by regulating oxidative stress, apoptosis, and autophagy.

The efficacy and risk factors of mechanical thrombectomy for the treatment of vertebrobasilar artery occlusion: a single center study.

BACKGROUND: The mortality of acute ischemic stroke patients caused by vertebrobasilar artery occlusion (VBAO) is high and mechanical thrombectomy has gradually become a promising treatment for acute ischemic stroke. This study analyzed the efficacy of mechanical thrombectomy and the risk factors associated with poor outcomes in VBAO patients caused by severe local atherosclerotic stenosis. METHODS: This retrospective study enrolled patients with acute ischemic stroke caused by VBAO between March 1, 2016 and August 31, 2019. Patient demographic and clinical data were collected retrospectively. All enrolled patients were retrospectively interviewed for at least 3 months. Patients with a modified Rankin scale (mRS) score between 0 and 3 points were defined as having satisfactory outcomes while those with more than 3 points were defined as having unsatisfactory outcomes. In-hospital mortality, the rates of recanalization, and the rates of intracerebral hemorrhage were also recorded. Multivariable logistic regression was used to determine the risk factors of unsatisfactory outcomes in enrolled patients. RESULTS: A total of 65 patients were enrolled in this study with a median age 69.0 (63.0-78.0) years and 48 patients (73.8%) were male. Approximately 50% of patients had a mRS score of 0 or 1 point within 90 days after treatment with mechanical thrombectomy and 14 patients had a mRS score of 6 points. A total of 11 patients died in hospital. Out of the 65 patients, 7 required recanalization and 9 patients suffered from intracerebral hemorrhage. Multivariate logistic regression analysis showed that older age, lower baseline posterior circulation acute stroke prognosis early CT score (pcASPECTS), higher baseline National Institutes of Health stroke scale (NIHSS) score, and residual stenosis were independent risk factors of both unsatisfactory outcomes and mortality of VBAO patients. CONCLUSIONS: This study confirmed the important role of mechanical thrombectomy in the treatment of acute ischemic stroke caused by VBAO and may provide some guidance for improving the prognosis of patients.

Protective effects of natural compounds against oxidative stress in ischemic diseases and cancers via activating the Nrf2 signaling pathway: A mini review.

Oxidative stress, an imbalance between reactive oxygen species and antioxidants, has been seen in the pathological states of many disorders such as ischemic diseases and cancers. Many natural compounds (NCs) have long been recognized to ameliorate oxidative stress due to their inherent antioxidant activities. The modulation of oxidative stress by NCs via activating the Nrf2 signaling pathway is summarized in the review. Three NCs, ursolic acid, betulinic acid, and curcumin, and the mechanisms of their cytoprotective effects are investigated in myocardial ischemia, cerebral ischemia, skin cancer, and prostate cancer. To promote the therapeutic performance of NCs with poor water solubility, the formulation approach, such as the nano drug delivery system, is elaborated as well in this review.

Pretreatment of Populus tomentiglandulosa protects hippocampal CA1 pyramidal neurons from ischemia-reperfusion injury in gerbils via increasing SODs expressions and maintaining BDNF and IGF-I expressions.

To examine the effects of Populus tomentiglandulosa (PT) extract on the expressions of antioxidant enzymes and neurotrophic factors in the cornu ammonis 1 (CA1) region of the hippocampus at 5 min after inducing transient global cerebral ischemia (TGCI) in gerbils, TGCI was induced by occlusion of common carotid arteries for 5 min. Before ischemic surgery, 200 mg·kg-1 PT extract was orally administrated once daily for 7 d. We performed neuronal nuclear antigen immunohistochemistry and Fluoro-Jade B staining. Furthermore, we determined in situ production of superoxide anion radical, expression levels of SOD1 and SOD2 as antioxidant enzymes and brain-derived neurotrophic factor (BDNF) and insulin-like growth factor I (IGF-I) as neurotrophic factors. Pretreatment with 200 mg·kg-1 PT extract prevented neuronal death (loss). Furthermore, pretreatment with 200 mg·kg-1 PT extract significantly inhibited the production of superoxide anion radical, increased expressions of SODs and maintained expressions of BDNF and IGF-I. Such increased expressions of SODs were maintained in the neurons after IRI. In summary, pretreated PT extract can significantly increase levels of SODs and protect the neurons against TGCI, suggesting that PT can be a useful natural agent to protect against TGCI.

FTY720 attenuates iron deposition and glial responses in improving delayed lesion and long-term outcomes of collagenase-induced intracerebral hemorrhage.

Most intracerebral hemorrhage (ICH) survivors have poor long-term outcomes, such as cognitive deficits and depression. Delayed lesions of ICH include neuron loss and white matter injury and the pathology of the lesions involves iron deposition and glial responses, which contribute to depressive-like behavior and cognitive impairment in animals. This study aimed to investigate the effects of FTY720 (0.3 mg/kg/day for 4 weeks) on iron deposition, glial responses, histological abnormalities and behavioral dysfunction in mice with ICH. The primary adverse long-term outcomes in our study of ICH mice were depressive-like behavior and impaired recognition memory. We found that FTY720 safely ameliorated depressive-like behavior and impaired recognition without affecting recovery of grip function and locomotor activity 28 days post-ICH. Moreover, we measured neuron loss, white matter lesions, lesion volume and iron deposition at day 28, which were attenuated in the FTY720-treated group compared to the ICH-control group, without changing initial hematoma volume on day 1 post-ICH. Long-term elevation of glial responses, including microglia activity and astrogliosis with tumor necrosis factor alpha (TNFα) expression was demonstrated by Western blot and immunofluorescence staining, which we found was attenuated by FTY720 treatment. Hence, FTY720 could become a novel therapeutic agent for improving long-term outcomes after ICH.