Flexible multilevel nonvolatile biocompatible memristor with high durability.

Current protein or glucose based biomemristors have low resistance-switching performance and require complex structural designs, significantly hindering the development of implantable memristor devices. It is imperative to discover novel candidate materials for biomemristor with high durability and excellent biosafety for implantable health monitoring. Herein, we initially demonstrate the resistance switching characteristics of a nonvolatile memristor in a configuration of Pt/AlOOH/ITO consisting of biocompatible AlOOH nanosheets sandwiched between a Indium Tin Oxides (ITO) electrode and a platinum (Pt) counter-electrode. The hydrothermally synthesized AlOOH nanosheets have excellent biocompatibility as confirmed through the Cell Counting Kit-8 (CCK-8) tests. Four discrete resistance levels are achieved in this assembled device in responsible to different compliance currents (ICC) for the set process, where the emerging multilevel states show high durability over 103 cycles, outperforming the protein-based biomemristors under similar conditions. The excellent performance of the Pt/AlOOH/ITO memristor is attributed to the significant role of hydrogen proton with pipe effect, as confirmed by both experimental results and density functional theory (DFT) analyses. The present results indicate the nonvolatile memristors with great potential as the next generation implantable multilevel resistive memories for long-term human health monitoring.

Haemostatic indexes for predicting intestinal necrosis in children with intussusception.

BACKGROUND: To determine risk factors for intestinal necrosis in intussusception cases among children with failed non-surgical reduction for intussusception. METHODS: Totally, 540 hospitalized individuals with unsuccessful air-enema reduction in our hospital between November 2010 and November 2020 were assessed in this retrospective study. The 540 intussusception cases were divided into the intestinal necrosis and non-intestinal necrosis groups. Haemostatic parameters, demographic and clinical features were assessed. Predictors of intestinal necrosis were examined by univariable and multivariable logistic regression analyses. RESULTS: Of the 540 patients included, 113 showed intestinal necrosis. This intestinal necrosis group had a longer duration of symptom or length of illness, younger ages, higher platelet counts, fibrinogen amounts and d-dimer levels (all P = 0.000) compared with the non-intestinal necrosis group. Multivariable analysis revealed that duration of symptom (odds ratio (OR) 1.12; 95% confidence interval (CI) 1.16-1.23, P = 0.000), fibrinogen (OR 1.26; 95% CI 1.10-1.31, P = 0.010) and d-dimer (OR 2.07; 95% CI 1.91-2.28, P = 0.000) independently predicted intestinal necrosis in individuals undergoing surgical reduction for intussusception. Receiver operating characteristic curve analysis showed that d-dimer amounts had the largest area under the curve for predicting intestinal necrosis. CONCLUSION: On admission, long duration of symptom, high fibrinogen and d-dimer levels are critical risk factors for intestinal necrosis development in children with unsuccessful non-surgical reduction. d-Dimer levels have the best predictive value for intestinal necrosis.

Effects of different dosing modes of calcium nitrate on P locking in sediment and nutrient concentrations in waters.

Sediment is an endogenous pollution source, which often leads water systems to eutrophication due to the release of nutrients, especially phosphorus (P). Calcium nitrate (CN) was dosed to the water systems under different modes to control P release from the sediments in this study. A 63-day static laboratory test was conducted to explore the effects of intermittent dosing and one-time dosing modes of CN on P locking in the sediment and the concentrations of nitrogen (N) and P in waters. Results showed that 89% total phosphorus (TP) in the overlying water and 91% TP in the interstitial water of sediment were reduced in the intermittent dosing reactor, which were 4% and 13% higher than those in the one-time dosing reactor, respectively. Thus, the concentration of TP in the overlying water of the dosing reactors was both below 0.1 mg/L during the whole experiment. Meanwhile, the mean values of oxidation-reduction potential (ORP) in the sediment increased to - 110.7 ± 42.02 mV when CN was added intermittently, which were significantly higher than those of the one-time dosing reactor (- 158.3 ± 44.61 mV) and control reactor (- 320.7 ± 0.05 mV). Compared with one-time dosing mode, the intermittent dosing not only reduced the maximum concentrations of NO2--N from 9.21 to 1.79 mg/L and NO3--N from 92.42 to 27.58 mg/L but also shorten their retention time in the overlying water, which might depress the toxic threats to aquatic animals in water environments. Therefore, the intermittent dosing of CN could not only improve the P locking effect but also minimize the risks to aquatic animals in water environments under the premise of reasonable dosage selected. In a word, this research provided an effective operation mode for locking P with CN in the heavily polluted water bodies, which is also advantageous to avoid toxic threats to aquatic animals in water environment.

Baicalin alleviates hyperglycemia-induced endothelial impairment 1 via Nrf2.

Baicalin is the major component found in Scutellaria baicalensis root, a widely used herb in traditional Chinese medicine, which exhibits strong anti-inflammatory, anti-viral and anti-tumor activities. The present work was devoted to elucidate the molecular and cellular mechanisms underlying the protective effects of Baicalin against diabetes-induced oxidative damage, inflammation and endothelial dysfunction. Diabetic mice, induced by streptozotocin (STZ), were treated with intraperitoneal Baicalin injections. Human umbilical vein endothelial cells (HUVECs) were cultured either in normal glucose (NG, 5.5 mM) or high glucose (HG, 33 mM) medium in the presence or absence of Baicalin for 72 h. We observed an obvious inhibition of hyperglycemia-triggered oxidative damage and inflammation in HUVECs and diabetic aortal vasculature by Baicalin, along with restoration of hyperglycemia-impaired nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway activity. However, the protective effects of Baicalin almost completely abolished in HUVECs transduced with shRNA against Nrf2, but not with nonsense shRNA. Mechanistic studies demonstrated that HG decreased Akt and GSK3B phosphorylation, restrained nuclear export of Fyn and nuclear localization of Nrf2, blunted Nrf2 downstream target genes, and subsequently induced oxidative stress in HUVECs. However, those destructive cascade, were well prevented by Baicalin in HUVECs. Furthermore, LY294002 and ML385 (inhibitor of PI3K and Nrf2) attenuated Baicalin mediated Nrf2 activation and the ability of facilitates angiogenesis in vivo and ex vivo. Taken together, the endothelial protective effect of Baicalin under hyperglycemia condition could be partly attributed to its role in downregulating reactive oxygen species (ROS) and inflammation via the Akt/GSK3B/Fyn-mediated Nrf2 activation.

Oral administration of propionic acid during lactation enhances the colonic barrier function.

BACKGROUND: Propionic acid is a three-carbon short chain fatty acid (SCFA) that has various effects on colonic functions. Although several studies have shown the effects of propionic acid on intestinal mucosal barrier function, studies of the promotion effect during pre-weaning are rare in the literature as far as we know. METHODS: Pre-weaning male Sprague-Dawley rats 7 days after birth were given an oral 0.2 mL/10 g of 200 mM propionic acid solution in the propionic acid group or normal saline solution in the control group by gavage twice a day for ten days. The proximal colonic contents were used for extraction and determination of propionic acid by gas chromatographic analysis; the transepithelial electrical resistance (TER) of colonic tissue was detected by an Ussing chamber; the alterations of ZO-1, Claudin-1, Claudin-8 and Occludin proteins were analyzed by Western blot and immunohistochemistry; and The activity of ERK and p38 MAPK was determined by the phosphorylation status of ERK1/2 and p38 with Western blot. RESULTS: Our results suggested a higher concentration (23.5 ± 1.9 mmol/kg) of propionic acid compared to the physiological concentration (18.1 ± 0.9 mmol/kg) in colonic contents after oral administration increased the value of TER and the expression of ZO-1, Claudin-1, Claudin-8 and Occludin compared to the control group. Furthermore, the expression levels of phosphorylated ERK1/2 and p38 MAPK were increased in propionic acid group. CONCLUSIONS: We concluded that continuous oral administration of propionic acid during lactation may increase its concentration in the proximal colon and promote epithelial barrier function of proximal colon by enhancing the expression of ZO-1, Claudin-8, Claudin-1 and Occludin via increases in the expression of ERK1/2 and p38 MAPK.

Risk factors associated with intestinal necrosis in children with failed non-surgical reduction for intussusception.

BACKGROUND: Intestinal necrosis is the most serious complication of intussusception. The risk factors associated with intestinal necrosis in pediatric patients with intussusception have not been well characterized. OBJECTIVE: This study aimed to investigate the risk factors associated with intestinal necrosis in pediatric patients with failed non-surgical reduction for intussusception. METHODS: Hospitalized patients who failed the air-enema reduction for intussusception in the outpatient department and subsequently underwent surgery were retrospectively reviewed. All cases were categorized into two groups: intestinal necrosis group and non-intestinal necrosis group based on the surgical findings. Demographic and clinical features including the findings from the surgery were recorded and analyzed. Factors associated with intestinal necrosis were analyzed using univariate and multivariate unconditional logistic regression analyses. RESULTS: A total of 728 cases were included. Among them, 171 had intestinal necrosis at the time of surgery. The group with intestinal necrosis had a longer duration of symptom or length of illness (P = 0.000), and younger (P = 0.000) than the non-intestinal necrosis group. Complex/compound type of intussusceptions is more likely to have intestinal necrosis. Multivariate analysis showed that the presence of grossly bloody stool (OR = 2.12; 95% CI 1.19-3.76, P = 0.010) and duration of symptom (OR = 1.07; 95% CI 1.06-1.08, P = 0.000) were independent risk factors for intestinal necrosis in patients hospitalized for surgical reduction for intussusceptions. CONCLUSION: At time of admission, the presence of bloody stools and duration of symptom are the important risk factors for developing intestinal necrosis for those patients who failed non-surgical reduction. The length of illness has the highest sensitivity and specificity to correlate with intestinal necrosis. This finding may suggest that we should take the intussusception cases that have the longer duration of symptom directly to operation room for reduction.