Effect of Crystallization Time on Behaviors of Glass-ceramic Produced from Sludge Incineration Ash

AbstractIncineration has become a significant treatment method for municipal sewage sludge because of the rising difficulty to find suitable sites for traditional landfill. However, a large amount of sludge incineration ash containing high levels of heavy metals is remained. In order to achieve resource utilization, glass–ceramics have been produced using sludge incineration ash. The optimum heat treatment was identified as Tn = 837°C for 1.0 h and Tc = 977°C for 2.0 h, respectively. The major crystalline phase identified from X-ray diffraction (XRD) and scanning electron microscopy (SEM) was wollastonite (CaSiO3) and the products displayed good performances. The results indicated that it was a feasible attempt to produce glass-ceramics from sludge incineration ash as decorative materials

The Genomic Analysis of Erythrocyte microRNA Expression in Sickle Cell Diseases

BACKGROUND: Since mature erythrocytes are terminally differentiated cells without nuclei and organelles, it is commonly thought that they do not contain nucleic acids. In this study, we have re-examined this issue by analyzing the transcriptome of a purified population of human mature erythrocytes from individuals with normal hemoglobin (HbAA) and homozygous sickle cell disease (HbSS). METHODS AND FINDINGS: Using a combination of microarray analysis, real-time RT-PCR and Northern blots, we found that mature erythrocytes, while lacking ribosomal and large-sized RNAs, contain abundant and diverse microRNAs. MicroRNA expression of erythrocytes was different from that of reticulocytes and leukocytes, and contributed the majority of the microRNA expression in whole blood. When we used microRNA microarrays to analyze erythrocytes from HbAA and HbSS individuals, we noted a dramatic difference in their microRNA expression pattern. We found that miR-320 played an important role for the down-regulation of its target gene, CD71 during reticulocyte terminal differentiation. Further investigation revealed that poor expression of miR-320 in HbSS cells was associated with their defective downregulation CD71 during terminal differentiation. CONCLUSIONS: In summary, we have discovered significant microRNA expression in human mature erythrocytes, which is dramatically altered in HbSS erythrocytes and their defect in terminal differentiation. Thus, the global analysis of microRNA expression in circulating erythrocytes can provide mechanistic insights into the disease phenotypes of erythrocyte diseases

Value of an Dynamic Eye-tracking Task in Assessing Unilateral Spatial Neglect after Stroke

Background Unilateral spatial neglect (USN) is a common post-stroke cognitive impairment that severely affects the functional recovery and quality of life of patients. Therefore, objective assessment of USN is essential to facilitate patients' functional recovery. Objective To investigate the feasibility of using adynamic eye-tracking task to assess USN in sub acute stroke patients. Methods Thirty inpatients in the sub acute phase after stroke in Department of Rehabilitation Medicine, Nanchong Central Hospital were recruited from September 2021 to July 2022. USN was assessed using the Behavioral Inattention Test-Conventional (BIT-C), Catherine Bergego Scale (CBS), and a two-minute dynamic eye-tracking task within one week of admission by two professional rehabilitation therapists, and adverse effects during the assessment were recorded. USN was diagnosed by a CBS score >0, a total BIT-C score <129, or gaze points distributed outside the four screen zones (gaze points distributed within the four screen zones were defined as non-USN). Correlation and consistency analyses were used to evaluate the results of the three assessments. Results In accordance with the performance assessment in conducting the dynamic eye-tracking task, 14 patients had left-sided neglect, and the other 16 had no USN. USN patients had a higher percentage of gaze points on the right side of the screen than non-USN patients (Z=-4.776, P<0.001). There was a significant difference in percentages of gaze points on the left and right side of the screen in USN patients (Z=-3.49, P<0.001). By BIT-C assessment, 15 patients were diagnosed with USN, and the remaining 15 patients had no USN. CBS assessment revealed that 16 patients had varying degrees of USN, and the remaining 14 were non-USN patients. The BIT-C and dynamic eye-tracking task were highly consistent in the assessment of USN (Kappa=0.933, P<0.001). Spearman's rank correlation analysis revealed a negative correlation between the percentage of gaze points on the right side of the screen and the total BIT-C score (rs=-0.776, P<0.001). The CBS and dynamic eye-tracking task had good agreement on the assessment of USN (Kappa=0.867, P<0.001) . Conclusion It is feasible to use the dynamic eye-tracking task to assess USN, because it is less time-consuming, with high level of patient participation and motivation, and there is a good consistency between the results assessed by it and BIT-C or CBS. Therefore, it can be used as a supplement to the standard USN assessment

Effects of Intellectual Activities on Different Domains of Cognitive Function in Elderly People

Background Intellectual activities such as reading and playing puzzle games can slow the decline of cognitive function in the elderly, but the effects of specific types of such activities on cognitive function and cognitive domains need to be further studied. Objective To explore the influence of common types of intellectual activities on cognitive function and cognitive domains of the elderly in the community. Methods From May to August 2022, stratified convenience sampling was used to select elderly people from four communities in Nanjing, Changzhou, Nantong and Xuzhou of Jiangsu Province. A face-to-face survey was conducted with a general information questionnaire and the Montreal Cognitive Assessment (MoCA) Beijing edition to collect data regarding sociodemographics, frequency and types of intellectual activities, and cognitive function. Stepwise multiple regression analysis was used to explore the relationship between intellectual activities and different cognitive domains. Results In total, 782 cases attended the survey, and 758 of them (96.93%) who completed it were included for analysis, including123 from Nanjing, 197 from Changzhou, 240 from Nantong, and 198 from Xuzhou. The intellectual activities done by these older people include learning new knowledge (n=170), playing chess and cards (n=228), reading (n=228), singing (n=59), playing puzzle games (n=57), helping grand children with their homework (n=42), painting (n=16), playing a musical instrument (n=47), and practicing calligraphy (n=30). Stepwise multiple linear regression analysis showed that learning new knowledge, reading, helping grand children with their homework, playing puzzle games and playing musical instruments were associated with cognitive function (P<0.05). Learning new knowledge (B=0.250), reading (B=0.590), playing puzzle games (B=0.585), helping grand children with their homework (B=0.711), and playing musical instruments (B=0.643) were the influencing factors of Visuospatial/Executive (P<0.05). Learning new knowledge (B=0.219) was an influencing factor of Abstraction and Delayed recall/Memory (B=0.727) (P<0.05). Reading was a factor affecting Naming (B=0.095), Attention (B=0.207), Language (B=0.290), Abstraction (B=0.241), and Delayed recall/Memory (B=0.377) (P<0.05). Playing puzzle games (B=0.290) and playing musical instruments (B=0.278) were the influencing factors of Language (P<0.05). Among various types of activities, reading was included in a total of seven regression equations, with a standardized regression coefficient of 0.225 for its impact on the total score of MoCA, which was higher than that of the other types. Conclusion Intellectual activities such as reading, learning new knowledge, playing puzzle games, helping grand children with their homework and playing a musical instrument can maintain or improve the cognitive function of the elderly in the community. The effects of different types of intellectual activities on cognitive function are domain-specific, which has a positive significance for the prevention and intervention of cognitive function decline of the elderly

Roles of astrocytic connexin-43, hemichannels, and gap junctions in oxygen-glucose deprivation/reperfusion injury induced neuroinflammation and the possible regulatory mechanisms of salvianolic acid B and carbenoxolone

Abstract Background Glia-mediated neuroinflammation is related to brain injury exacerbation after cerebral ischemia/reperfusion (I/R) injury. Astrocytic hemichannels or gap junctions, which were mainly formed by connexin-43, have been implicated in I/R damage. However, the exact roles of astrocytic hemichannels and gap junction in neuroinflammatory responses induced by I/R injury remain unknown. Methods Primary cultured astrocytes were subjected to OGD/R injury, an in vitro model of I/R injury. Salvianolic acid B (SalB) or carbenoxolone (CBX) were applied for those astrocytes. Besides, Cx43 mimetic peptides Gap19 or Gap26 were also applied during OGD/R injury; Cx43 protein levels were determined by western blot and cytoimmunofluorescene staining, hemichannel activities by Ethidium bromide uptake and ATP concentration detection, and gap junction intercellular communication (GJIC) permeability by parachute assay. Further, astrocyte-conditioned medium (ACM) was collected and incubated with microglia. Meanwhile, ATP or apyrase were applied to explore the role of ATP during OGD/R injury. Microglial activation, M1/M2 phenotypes, and M1/M2-related cytokines were detected. Also, microglia-conditioned medium (MEM) was collected and incubated with astrocytes to further investigate its influence on astrocytic hemichannel activity and GJIC permeability. Lastly, effects of ACM and MCM on neuronal viability were detected by flow cytometry. Results We found that OGD/R induced abnormally opened hemichannels with increased ATP release and EtBr uptake but reduced GJIC permeability. WB tests showed decreased astrocytic plasma membrane’s Cx43, while showing an increase in cytoplasma. Treating OGD/R-injured microglia with ATP or OGD/R-ACM induced further microglial activation and secondary pro-inflammatory cytokine release, with the M1 phenotype predominating. Conversely, astrocytes incubated with OGD/R-MCM exhibited increased hemichannel opening but reduced GJIC coupling. Both SalB and CBX inhibited abnormal astrocytic hemichannel opening and ATP release and switched the activated microglial phenotype from M1 to M2, thus providing effective neuroprotection. Application of Gap19 or Gap26 showed similar results with CBX. We also found that OGD/R injury caused both plasma membrane p-Cx43(Ser265) and p-Src(Tyr416) significantly upregulated; application of SalB may be inhibiting Src kinase and attenuating Cx43 internalization. Meanwhile, CBX treatment induced obviously downregulation of p-Cx43(Ser368) and p-PKC(Ser729) protein levels in plasma membrane. Conclusions We propose a vicious cycle exists between astrocytic hemichannel and microglial activation after OGD/R injury, which would aggravate neuroinflammatory responses and neuronal damage. Astrocytic Cx43, hemichannels, and GJIC play critical roles in OGD/R injury-induced neuroinflammatory responses; treatment differentially targeting astrocytic Cx43, hemichannels, and GJIC may provide novel avenues for therapeutics during cerebral I/R injury

Microstructure and evolution of hafnium carbide whiskers via polymer-derived ceramics: A novel formation mechanism

Polymer-derived ultra-high-temperature ceramic (UHTC) nanocomposites have attracted growing attention due to the increasing demands for advanced thermal structure components in aerospace. Herein, hafnium carbide (HfC) whiskers are successfully fabricated in carbon fiber preforms via the polymer-derived ceramic (PDC) method. A novel carbon nanotube (CNT) template growth mechanism combined with the PDC method is proposed in this work, which is different from the conventional vapor-liquid-solid (VLS) mechanism that is commonly used for polymer-derived nanostructured ceramics. The CNTs are synthesized and proved to be the templates for fabricating the HfC whiskers, which are generated by the released low-molecular-weight gas such as CO, CO2, and CH4 during the pyrolysis of a Hf-containing precursor. The formed products are composed of inner single crystal HfC whiskers that are measured to be several tens of micrometers in length and 100-200 nm in diameter and outer HfC/HfO2 particles. Our work not only proposes a new strategy to prepare the HfC whiskers, but also puts forward a new thinking of the efficient utilization of a UHTC polymer precursor

Astrocytic gap junction inhibition by carbenoxolone enhances the protective effects of ischemic preconditioning following cerebral ischemia

Abstract Background Stroke is the second leading cause of death worldwide and the most common cause of adult-acquired disability in many nations. Thus, attenuating the damage after ischemic injury and improving patient prognosis are of great importance. We have indicated that ischemic preconditioning (IP) can effectively reduce the damage of ischemia reperfusion and that inhibition of gap junctions may further reduce this damage. Although we confirmed that the function of gap junctions is closely associated with glutamate, we did not investigate the mechanism. In the present study, we aimed to clarify whether the blockade of cellular communication at gap junctions leads to significant reductions in the levels of glutamate released by astrocytes following cerebral ischemia. Methods To explore this hypothesis, we utilized the specific blocking agent carbenoxolone (CBX) to inhibit the opening and internalization of connexin 43 channels in an in vitro model of oxygen-glucose deprivation/re-oxygenation (OGD/R), following IP. Results OGD/R resulted in extensive astrocytic glutamate release following upregulation of hemichannel activity, thus increasing reactive oxygen species (ROS) generation and subsequent cell death. However, we observed significant increases in neuronal survival in neuron-astrocyte co-cultures that were subjected to IP prior to OGD/R. Moreover, the addition of CBX enhanced the protective effects of IP during the re-oxygenation period following OGD, by means of blocking the release of glutamate, increasing the level of the excitatory amino acid transporter 1, and downregulating glutamine expression. Conclusions Our results suggest that combined use of IP and CBX represents a novel therapeutic strategy to attenuate damage from cerebral ischemia with minimal adverse side effects