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In this work, the kinetics study on the reaction between CO2 and tertiary amine catalyzed by zinc(II)‐1,4,8,11‐tetraazacyclotetradecane complexes (CM) and zinc(II)‐1,4,7,10‐tetraazacyclododecane complexes (CN) was carried out in a stopped‐flow device. The effects of the catalyst concentration, type of tertiary amines, and temperature on the reaction rate (ν) and catalytic activity (φ) were studied. It was found that the catalyst concentration, tertiary amine with higher pKa, and temperature had positive effects on ν. ν in N‐methyl diethanolamine solution with 10.0 mol m−3 CM and CN were 16.62 and 26.05 folds than the uncatalyzed ν at 298 K, respectively. φ increased with increasing catalyst concentration, decreasing temperature and tertiary amine's pKa. In addition, the kinetics behavior of tertiary amine‐CM/CN‐CO2 systems conformed to the Michaelis–Menten model. The activation energies in catalytic systems were 4%–15% lower than that in the non‐catalytic systems. [ABSTRACT FROM AUTHOR]

Objective: To explore the safety of the corona mortis of the minimally invasive plate insertion in treatment of the anterior pelvic ring fracture by studying the relationship between the vessel and the position of plate. Method: The corona mortis was dissected out of eight adult cadavers and were simulated for the insertion of the anterior ring minimally invasive plate, and the presence of the anastomotic branch (the corona mortis) in the suprapubic branch area was observed. After the Corona mortis stripped off, the data was measured, such as the length, vessel diameter, distance from the pubic tubercle, and the maximum vertical distance between the corona mortis and the pubis. The measured data and the previous literatures were analyzed to study the morphology of the corona mortis and the position relation between the corona mortis and the placement of subperiosteal tunnel through the minimally invasive ilioinguinal approach. Results: Out of the 16 unilateral pelvises, the corona mortis were observed on 12 unilateral pelvises with an incidence rate of 75%. Amongst them, there were seven cases of vein anastomosis (incidence of 43.75%), three cases of arterial anastomosis (incidence of 18.75%), and two cases of both arterial anastomosis and vein anastomosis (incidence of 12.5%). The corona mortis length ranged between 24.5 and 37.5 mm (average of 30.7 ± 3.6 mm); the diameter ranged between 1.6 and 3.5 mm (average of 2.5 ± 0.5 mm) and the distance between the vessels and the pubic tubercle was between 53.9 and 65.2 mm (average of 59.0 ± 3.6 mm). Above the pubis, the corona mortis originated from the iliac or the inferior epigastric vessel. It crossed the pubic branch to the dorsal side of the pubis and proceeded downward to anastomize with the obturator vessels near the obturator. Toothless tweezers were used to peel and lift up the corona mortis from the pubic bone. The maximum vertical distance between the corona mortis and the pubis ranged between 8.8 and 18.3 mm (average of 12.6 ± 3.0 mm). Conclusion: The corona mortis have a high rate of incidence, with a large number of differences in the type and shape of blood vessels among patients. Following peeling, the movement between the corona mortis and pubic bone is limited. Nevertheless, the plate and bone exfoliator still passed safely. Therefore, when surgeons use the minimally invasive ilioinguinal approach to establish channels, the process of subperiosteal stripping must be performed to avoid any accidental injury. [ABSTRACT FROM AUTHOR]

Pot seedling transplanting is the main way of vegetable planting, there were some problems of labor intensity and low level of automation in the process of mechanized transplanting of vegetable pot seedling. Aiming at this problem, this paper designed an intelligent transplanting system for vegetable pot seedling, which included the function of the seeding storage mechanism, the seedling feeding mechanism, the ejecting seedling mechanism, the pinch mechanism and the planting mechanism, the system monitors the whole movement process of planting through pressure sensing, stroke detection and limit switch, obtains each planting stage of the seedlings during planting, and uses the CCD camera to identify the key steps of planting and seedlings to determine whether it is missing. Three broccoli seedlings with different moisture content and the age of 42d were used as the experimental object of seedlings planting experiment. Results indicated that: Under the conditions of meeting the agronomic requirements of vegetable pot seedlings, when the speed of picking-up seedlings was 75 seedlings per minute, which resulted in a 95% success rate of picking-up seedlings and 5% leaked seedlings rate, the planting effect of vegetable pot seedlings was the best. The research can provide useful reference for the development of intelligent transplanting technology of vegetable pot seedling. [ABSTRACT FROM AUTHOR]

Astrocytes have important functions in the central nervous system (CNS) and are significant in our understanding of the neuronal network. Astrocytes modulate neuronal firings at both single cell level of tripartite synapses and the neuron-glial network level. Astrocytes release adenosine triphosphate (ATP) and glutamate into the neuron-glial network. These gliotransmitters diffuse over the network to form long distance signals to regulate neuron firings. In this paper, we study a neuron-glial network model that includes a diffusion of astrocytic ATP and glutamate to investigate how long distance diffusion of the gliotransmitters affects the information processing in a neuronal network. We find that gliotransmitters diffusion can compensate for the failure of information processing of interneuron network firings induced by defectively coupled synapses. Moreover, we find that calcium waves in astrocyte network and firings in interneuron network are both sensitive to the glutamate diffusion rate and feedback intensities of astrocytes on interneurons. [ABSTRACT FROM AUTHOR]

Gut dysbiosis and dysregulation of gut–brain communication have been identified in hypertensive patients and animal models. Previous studies have shown that probiotic or prebiotic treatments exert positive effects on the pathophysiology of hypertension. This study aimed to examine the hypothesis that the microbiota-gut-brain axis is involved in the antihypertensive effects of curcumin, a potential prebiotic obtained from Curcuma longa. Male 8- to 10-week-old spontaneously hypertensive rats (SHRs) and Wistar Kyoto (WKY) rats were divided into four groups: WKY rats and SHRs treated with vehicle and SHRs treated with curcumin in dosage of 100 or 300 mg/kg/day for 12 weeks. Our results show that the elevated blood pressure of SHRs was markedly decreased in both curcumin-treated groups. Curcumin treatment also altered the gut microbial composition and improved intestinal pathology and integrity. These factors were associated with reduced neuroinflammation and oxidative stress in the hypothalamus paraventricular nucleus (PVN). Moreover, curcumin treatment increased butyrate levels in the plasma, which may be the result of increased butyrate-producing gut microorganisms. In addition, curcumin treatment also activated G protein-coupled receptor 43 (GPR 43) in the PVN. These results indicate that curcumin reshapes the composition of the gut microbiota and ameliorates the dysregulation of the gut-brain communication to induce antihypertensive effects. [Display omitted] • Curcumin ameliorated hypertension and cardiac hypertrophy. • Curcumin altered composition of intestinal microbiota and reshaped gut microbiome. • Curcumin attenuated neuroinflammation and oxidative stress in the PVN. • Microbiota-gut-brain axis are involved in the antihypertensive effect of curcumin. [ABSTRACT FROM AUTHOR]

The hypothalamic paraventricular nucleus (PVN) plays crucial roles in central cardiovascular regulation. Increasing evidence in humans and rodents shows that vitamin D intake is important for achieving optimal cardiovascular function. The purpose of this study was to investigate whether calcitriol, an active form of vitamin D, improves autonomic and cardiovascular function in hypertensive rats and whether PVN oxidative stress and inflammation are involved in these beneficial effects. Male spontaneously hypertensive rats (SHR) and normotensive control Wistar Kyoto (WKY) rats were treated with either calcitriol (40 ng/day) or vehicle (0.11 μL/h) through chronic PVN infusion for 4 weeks. Blood pressure and heart rate were recorded continuously by radiotelemetry. PVN tissue, heart and plasma were collected for molecular and histological analysis. Compared to WKY rats, SHR exhibited increased systolic blood pressure, sympathetic drive, and cardiac hypertrophy and remodeling. These were associated with higher mRNA and protein expression levels of high mobility box 1 (HMGB1), receptor for advanced glycation end products (RAGE), toll-like receptor 4 (TLR4), nuclear factor-kappa B (NF-κB), proinflammatory cytokines, NADPH oxidase subunit in the PVN. In addition, increased norepinephrine in plasma, elevated reactive oxygen species levels and activation of microglia in the PVN were also observed in SHR. Chronic calcitriol treatment ameliorated these changes but not in WKY rats. Our results demonstrate that chronic infusion of calcitriol in the PVN ameliorates hypertensive responses, sympathoexcitation and retains cardiovascular function in SHR. Reduced inflammation and oxidative stress within the PVN are involved in these calcitriol-induced effects. • PVN infusion of calcitriol ameliorates autonomic dysfunction and hypertension. • Chronic calcitriol treatmen attenuates cardiac hypertrophy and remodeling. • Chronic calcitriol treatment reduces PVN neuroinflammation and oxidative stress. • HMGB1-RAGE/TLR4-NF-κB axis in PVN is associated with the effects of calcitriol. [ABSTRACT FROM AUTHOR]

Purpose: It has previously been reported that repeated exposure to hypoxia increases spleen size and haemoglobin (HGB) level and recent reports on the effect apnoea has on spleen size and haematological parameters are contradictory. Therefore, this study aims to evaluate the effect apnoea training has on spleen size and haematological parameters. Methods: The breath-holding (BH) group was comprised of 12 local student-athletes with no BH exercise experience who performed BH jogging and BH jumping rope dynamic apnoea protocols, five times weekly for 8 weeks. The BH event duration was progressively increased as the apnoea tolerance of the athletes improved (20 to 35 s). The same training task was performed by the control group ( n = 10) without BH. Spleen sizes were measured with an ultrasound system and a complete blood cell analysis was performed on the median cubital venous blood. Results: Spleen volume in the BH group increased from 109 ± 13 ml to 136 ± 13 ml ( p < 0.001), and bulky platelets decreased from 70.50 ± 5.83 to 65.17 ± 5.87 ( p = 0.034), but no changes were recorded for erythrocytes ( p = 0.914), HGB ( p = 0.637), PLTs ( p = 0.346) and WBC ( p = 0.532). No changes were recorded for the control group regarding spleen size or haematological parameters. Conclusion: Eight weeks of dry dynamic apnoea training increased spleen size and decreased the number of circulating bulky platelets in the athletes who were assessed in this study. However, the baseline RBC counts and HGB levels of the athletes were not altered by the training programme., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yang, Wang, Yu, Cui, Yu, Jiang, Gou and Du.)

The study aims to enhance β-amyrin production in Saccharomyces cerevisiae by peroxisome compartmentalization. First, overaccumulated squalene was determined as a key limiting factor for the production of β-amyrin since it could inhibit the activity of β-amyrin synthase GgbAs1. Second, to mitigate the inhibition effect, the enhanced squalene synthesis pathway was compartmentalized into peroxisomes to insulate overaccumulated squalene from GgbAs1, and thus the specific titer of β-amyrin reached 57.8 mg/g dry cell weight (DCW), which was 2.6-fold higher than that of the cytosol engineering strain. Third, by combining peroxisome compartmentalization with the "push-pull-restrain" strategy (ERG1 and GgbAs1 overexpression and ERG7 weakening), the production of β-amyrin was further increased to 81.0 mg/g DCW (347.0 mg/L). Finally, through fed-batch fermentation in a 5 L fermenter, the titer of β-amyrin reached 2.6 g/L, which is the highest reported to date. The study provides a new perspective to engineering yeasts as a platform for triterpene production.