Effect of dexmedetomidine on perioperative haemodynamics and early cognitive function in elderly patients undergoing laparoscopic surgery.

Introduction: Laparoscopic minimally invasive surgery has been widely used in the diagnosis and treatment of gynaecological diseases. Aim: To investigate the effect of dexmedetomidine on perioperative haemodynamics and cognitive function in elderly gynaecological patients who underwent laparoscopic surgery. Material and methods: Clinical baseline characteristics, haemodynamic parameters, renin activity, norepinephrine level, cognitive function, pain level, and sedation were compared between the 2 groups. Results: At T4 (10 min after extubation) and T5 (1 h after extubation), significant differences were found in systolic blood pressure, diastolic blood pressure, and heart rate between the 2 groups (p < 0.05); renin activity and norepinephrine level were much lower in the dexmedetomidine group than in the control group at T3 (10 min before extubation) and T4 (p < 0.05). One day before surgery, there were no significant differences in Mini-mental state examination (MMSE), visual analogue scale (VAS), and Ramsay scores between the 2 groups (p > 0.05), but the MMSE score 1 day after surgery and the Ramsay score at 12 h after surgery in the dexmedetomidine group were much higher than that in the control group (p < 0.05). Notably, at 2, 4, 12, 24, and 48 h after surgery, the VAS score in the dexmedetomidine group was significantly lower than that in the control group (p < 0.05). Conclusions: Dexmedetomidine has a better clinical effect in improving perioperative haemodynamics and early cognitive function in elderly gynaecological patients who received laparoscopic surgery.

Genome-wide identification and analysis of the MAPKK gene family in Chinese mitten crab (Eriocheir sinensis) and its response to bacterial challenge.

Protein kinases of the MAPK cascade family (MAPKKK-MAPKK-MAPK) play an important role in the growth and development of organisms and their response to environmental stress. The MAPKK gene families in the Chinese mitten crab Eriocheir sinensis have never been systematically analyzed. We identified four MAPKK family genes, EsMEK, EsMAPKK4, EsMAPKK6, and EsMAPKK7, in E. sinensis and analyzed their molecular features and expression patterns. All four MAPKK genes are composed of multiple exons and introns, all have a conserved domain, and all have 10 conserved motifs (except EsMEK and EsMAPKK7 which are missing motif 10). The four MAPKK genes are on four different chromosomes and have no gene duplications, and the results of phylogenetic tree analysis indicate that the ESMAPKK gene family is highly conserved evolutionarily. The EsMAPKK genes were widely expressed in all the examined tissues with higher expression in hemocytes, hepatopancreas, and gills. Notably, EsMAPKK6 was also highly expressed in the ovary. Vibrio parahaemolyticus infection significantly increased the mRNA levels of the EsMAPKK genes in hemocytes. Further disruption of the EsMAPKK gene family expression affects the expression levels of multiple antimicrobial peptides in hemocytes. Our experimental results provide a starting point for a more in-depth study of the innate immunity functional roles of members of the MAPKK gene families in E. sinensis.

Immune functions of the Dscam extracellular variable region in Chinese mitten crab.

In arthropods, there is only a single copy of Down Syndrome Cell Adhesion Molecule (Dscam) in the genome, but it can exist as numerous splice variants. There are three hypervariable exons in the extracellular domain and one hypervariable exon in the transmembrane domain. In Chinese mitten crab (Eriocheir sinensis), exons 4, 6 and 14 can produce 25, 34 and 18 alternative splice variants, respectively. In this study, through Illumina sequencing, we identified additional splice variants for exons 6 and 14, hence there may be > 50,000 Dscam protein variants. Sequencing of exons 4, 6 and 14 showed that alternative splicing was altered after bacterial stimulation. Therefore, we expressed and purified the extracellular variable region of Dscam (EsDscam-Ig1-Ig7). Exons 4.3, 6.46 and 14.18, three variable exons of the recombinant protein, were randomly selected. The functions of EsDscam-Ig1-Ig7 in immune defences of E. sinensis were subsequently explored. EsDscam-Ig1-Ig7 was discovered to bind to both Gram-positive Staphylococcus aureus and Gram-negative Vibrio parahaemolyticus, but it did not exhibit antibacterial activity. By promoting hemocyte phagocytosis and bacterial removal, EsDscam-Ig1-Ig7 can also shield the host from bacterial infection. The findings highlight the immunological activities of Dscam alternative splicing and reveal the potential for many more Dscam isoforms than were previously predicted in E. sinensis.

Deubiquitinase cylindromatosis (CYLD) regulates antibacterial immunity and apoptosis in Chinese mitten crab (Eriocheir sinensis).

Ubiquitination and deubiquitination of target proteins is an important mechanism for cells to rapidly respond to changes in the external environment. The deubiquitinase, cylindromatosis (CYLD), is a tumor suppressor protein. CYLD from Drosophila melanogaster participates in the antimicrobial immune response. In vertebrates, CYLD also regulates bacterial-induced apoptosis. However, whether CYLD can regulate the bacterial-induced innate immune response in crustaceans is unknown. In the present study, we reported the identification and cloning of CYLD in Chinese mitten crab, Eriocheir sinensis. Quantitative real-time reverse transcription polymerase chain reaction analysis showed that EsCYLD was widely expressed in all the examined tissues and was upregulated in the hemolymph after Vibrio parahaemolyticus challenge. Knockdown of EsCYLD in hemocytes promoted the cytoplasm-to-nucleus translocation of transcription factor Relish under V. parahaemolyticus stimulation and increased the expression of corresponding antimicrobial peptides. In vivo, silencing of EsCYLD promoted the removal of bacteria from the crabs and enhanced their survival. In addition, interfering with EsCYLD expression inhibited apoptosis of crab hemocytes caused by V. parahaemolyticus stimulation. In summary, our findings revealed that EsCYLD negatively regulates the nuclear translocation of Relish to affect the expression of corresponding antimicrobial peptides and regulates the apoptosis of crab hemocytes, thus indirectly participating in the innate immunity of E. sinensis.

Integrinß1/FAK/ERK signalling pathway is essential for Chinese mitten crab Eriocheir sinensis hemocyte survival.

Integrins are cellular adhesion molecules that mediate cell-cell, cell-extracellular matrix, and cell-pathogen interactions. Integrins can stimulate various signaling pathways by binding to different ligands, thereby exerting immunological functions. While integrins have been found to primarily play a role in bacterial agglutination, phagocytosis, and inhibition of apoptosis in invertebrates, the specific signaling pathway and mechanism of action remain unclear. In vertebrates, ß1 integrin and extracellular matrix interactions can associate with focal adhesion kinase (FAK) to initiate MAPK/ERK signaling and regulate cell survival; however, in invertebrates (e.g., Chinese mitten crab), the mechanisms of integrins are poorly understood. The purpose of this study was to investigate whether integrinß1/FAK activation of the MAPK/ERK pathway regulates hemocyte survival and the associated mechanism. Treatment with an integrinß1 inhibitor RGD (a conserved tripeptide Arg-Gly-Asp), decreased the levels of FAK and ERK expression and phosphorylation, followed by an intensification of apoptosis. Similar results were obtained following siRNA knockdown of integrinß1 expression. We further found that the attenuation of ERK phosphorylation enhanced the level of Caspase-3 expression. Together, these findings suggest that integrinß1 activates the FAK/ERK signaling cascade and is involved in the survival of Chinese mitten crab hemocytes.

The extracellular non-variable region of Dscam promotes bacterial clearance by promoting phagocytosis of hemocytes in Eriocheir sinensis.

As the most typical example of mRNA variable splicing, Down Syndrome Cell Adhesion Molecule (Dscam) can produce a large number of mRNA isomers. It plays an important role not only in the nervous system, but also in the immune system. In Eriocheir sinensis, the extracellular region of Dscam has three variable domains, which can produce 25, 34 and 18 exons and encode the N-terminal region of immunoglobulin (Ig) 2 and Ig3 domains, and the entire Ig7 domain, respectively. In addition to three variable domains, the extracellular non-variable region of Dscam also includes many Ig domains and fibronectin type III (FNIII) domains. However, the role of the extracellular non-variable region function of Dscam in the immune defense of E. sinensis is unclear. In this study, we focused on the role of the extracellular non-variable region of Dscam in crab immune defense. The results indicate that the extracellular non-variable region of Dscam can bind bacteria and has bacteriostatic function. At the same time, the extracellular non-variable region of Dscam can also directly promote bacterial clearance by promoting phagocytosis of hemocytes.

Microstructure and Properties of ZrB2-SiC Reinforced Copper Matrix Composite Coatings Prepared by Laser Cladding.

With the use of electrolytic Cu powder, Zr powder, Si powder and nickel-coated B4C powder as cladding powders, in-situ synthesized ZrB2-SiC reinforced copper matrix composite coatings were prepared by laser cladding on the surface of the copper substrate to improve the surface hardness and wear resistance. Under the condition of a laser energy density at 60 kJ/cm2, the macroscopic surface of the composite coating was continuously flat. The microstructure and phase of the cladding coating were analyzed by means of XRD and SEM. The reinforcements with nano-scale particle and micron-scale needle-like structures were in-situ synthesized in the cladding coating, and the content of the reinforcement phase decreased slightly from the coating surface to the substrate. The phase analysis results showed that the reinforcements included ZrB2 and SiC. When the content of the reinforcement was increased to 30 wt%, microhardness also increased from 48 HV0.2 to 309 HV0.2, which was about 5.6 times that of the copper matrix. The wear resistance of the composite coatings was characterized by current-carrying wear tests. By keeping the sliding speed and load constant, the wear rate decreased with an increase in the reinforcement content, and the wear mechanism changed from adhesive wear to abrasive wear. The wear rate of the composite coating with the current was higher than that without the current due to its electric ablation and high temperature.

Suppressed COP9 signalosome 5 promotes hemocyte proliferation through Cyclin E in the early G1 phase to defend against bacterial infection in crab.

Hemocytes are invertebrate immune cells that are similar to blood cells in vertebrates and play a crucial role in innate immunity. Previous work has found that mature circulating hemocytes lack the ability to proliferate. However, recent single-cell RNA sequencing and functional studies in invertebrate have challenged this view. Here, we report that bacteria induced hemocytes proliferation in the Chinese mitten crab, Eriocheir sinensis. Flow cytometry was used to collect non-proliferating and proliferating hemocytes populations, while the expression of EsCyclin E was highly expressed in proliferating hemocytes, but the expression of EsCsn5 was significantly suppressed in proliferating hemocytes. Subsequent studies have found EsCsn5 distributed in two fractions include holo-complex and monomeric form, whereas knockdown of EsCsn5 has little impact on the amount of the holo-complex. EsCsn5 was widely expressed in different crab tissues, while its expression was significantly reduced upon bacterial infection. Crab hemocytes showed significantly enhanced proliferation when EsCsn5 was genetically knocked down, suggesting a critical role for CSN5 in the negative regulation of crab hemocyte proliferation. Moreover, EsCSN5 but not the EsCSN8 was demonstrated to negatively regulate the early G1 phase of the cell cycle by controlling the degradation of EsCyclin E through ubiquitination steps, rather than affecting its transcription. Furthermore, in the EsCyclin E-suppressed crab there was a significantly reduced survival rate and an up-regulated hemolymph bacterial concentration. Taken together, this study provides evidence demonstrating that invertebrate hemocytes down-regulate the expression of EsCsn5 upon bacterial challenge, thus promoting proliferation in an EsCyclin E-dependent manner in order to protect the crab from infection.

Photoinduced release of odorous volatile organic compounds from aqueous pollutants: The role of reactive oxygen species in increasing risk during cross-media transformation.

Photoinduced volatile organic compounds (VOCs) release from fatty alcohols at the air-water interface, has attracted considerable attention. This paper comprehensively explores the release of odorous VOCs from aqueous micropollutants under photoirradiation, especially in terms of the important role of the reactive oxygen species (ROS) in increased risk by cross-media transformation. The formation and distribution of photoinduced VOCs produced by aqueous benzyl alcohol (BzOH), a common ingredient in personal care products, were monitored in situ by online gas chromatography equipped with mass spectrometry and flame ionization detector (GC-MS/FID). The photoreaction of BzOH followed first-order kinetics with a rate constant of 0.0158/min under air. After 180 min of ultraviolet irradiation, the accumulated output of the gas-phase products benzene and benzaldehyde (BA) reached 3.8 µmol and 2.6 µmol respectively, being approximately 10 times that under nitrogen. According to electron paramagnetic resonance measurements, singlet oxygen mainly promoted the oxidation of BzOH to BA, which was an important intermediate producing benzene via photocleavage. Odorous alicyclic hydrocarbons were also generated through photorearrangement under nitrogen. On the other hand, the Henry's law constants of the main products were much lower than those of BzOH, indicating that the photoproducts would volatilize from the aqueous phase into the gas phase. The odor threshold of gas-phase products decreased to varying degrees after photoirradiation. Especially for BA, one of the main products, its odor threshold decreased 130 times compared with BzOH. This study shows that the risk of cross-media pollution could significantly increase due to the transformation of aqueous pollutants into odorous VOCs under photoirradiation and provides new insight into its risk prevention.

Transcriptome-wide analysis of cellular immune response stimulated by nuclear input of different down syndrome cell adhesion molecule intracellular domains.

In arthropods, Dscam (Down syndrome cell adhesion molecule) produces multiple pathogen specific receptors via immune responsive alternative splicing, generating molecular complexity analogous to vertebrate antibodies. Fewer isoforms are produced by the exons encoding Dscam's intracellular domain (ICD); therefore, the present study aimed to determine the transcriptional response of Eriocheir sinensis to Dscam ICDs. In the group overexpressing all cytoplasmic tail exons (ICD-FL), 1401 differentially expressed genes (DEGs) were identified; overexpressed of ICD constructs lacking exon-35 (ICD-△35) identified 413 DEGs; and overexpression of ICD constructs lacking exon-35 and exon-36 (ICD-△35 + 36) identified 22 DEGs. The DEGs were enriched in immunity and metabolism-related pathways. The expression of selected genes was confirmed using quantitative real-time reverse transcription PCR. The transcriptomes of Drosophila S2 cells overexpressing different ICDs were then determined. We identified key immune, metabolic, and cell proliferation-regulated genes and gene networks, providing insights into the membrane-to-nuclear signaling pathway of Dscam.

A promising catalytic solution of NO reduction by CO using g-C3N4/TiO2: A DFT study.

The direct catalytic reduction of nitric oxide (NO) by carbon monoxide (CO) to form harmless N2 and CO2 is an ideal strategy to simultaneously remove both these hazardous gases. To investigate the feasibility of using graphitic carbon nitride/titanium dioxide (g-C3N4/TiO2) to catalyze the NO reduction by CO, we systematically explore the effect of the interfacial coupling between g-C3N4 and TiO2 on the photo-induced carrier separation, the light absorption, and the surface reaction for the NO reduction by using density functional theory. The g-C3N4/TiO2 is predicted to have a better photocatalytic activity for NO reduction than g-C3N4, due to the enhanced light absorption intensity and the accelerated separation of the photo-excited electron-hole pairs. By comparing the reaction routes on g-C3N4/TiO2 and g-C3N4, the results indicate that the introduction of TiO2 can keep the surface reaction process intact with the NO dissociation (N2O formation) being the rate-determining (crucial) step. Moreover, TiO2 can facilitate the desorption of NO reduction products, avoiding the deactivation of g-C3N4. This work shows that the composition of TiO2 into g-C3N4 provides a promising catalyst in NO reduction by CO.

Down Syndrome Cell Adhesion Molecule Triggers Membrane-to-Nucleus Signaling-Regulated Hemocyte Proliferation against Bacterial Infection in Invertebrates.

Down syndrome cell adhesion molecule (Dscam) generates tens of thousands of isoforms by alternative splicing, thereby providing crucial functions during immune responses. In this study, a novel Dscam signaling pathway was investigated in crab, which remains poorly characterized in invertebrates. Bacterial infection induced the cytoplasmic cleavage of Dscam intracellular domains (ICDs) by γ-secretase, and then the released ICDs carrying specific alternatively spliced exons could directly interact with IPO5 to facilitate nuclear translocation. Nuclear imported ICDs thus promoted hemocyte proliferation and protect the host from bacterial infection. Protein-interaction studies revealed that the ectodomain of Dscam bound to a disintegrin and metalloprotease domain 10 (ADAM10) rather than ADAM17. Inhibition or overexpression of ADAM10 impaired or accelerated Dscam shedding activity post-bacterial stimulation, respectively. Moreover, the shedding signal then mediated Dscam with an intact cytoplasmic domain to promote the cleavage of ICDs by γ-secretase. Furthermore, the transcription of ADAM10 was regulated by Dscam-induced canonical signaling, but not nuclear imported ICDs, to serve as a feedback regulation between two different Dscam pathways. Thus, membrane-to-nuclear signaling of Dscam regulated hemocyte proliferation in response to bacterial infection.

An ancient interleukin-16-like molecule regulates hemocyte proliferation via integrin ß1 in invertebrates.

Interleukins (ILs) are cytokines with crucial functions in innate and adaptive immunity. IL genes are only found in vertebrates, except for IL-16, which has been cloned in some arthropod species. However, the function of this gene in invertebrates is unknown. In the present study, an IL-16-like gene (EsIL-16) was identified from the Chinese mitten crab Eriocheir sinensis. EsIL-16 was predicted to encode a precursor (proEsIL-16) that shares similarities with pro-IL-16 proteins from insects and vertebrates. We show that caspase-3 processes proEsIL-16 into an approximately 144-kDa N-terminal prodomain with nuclear import activity and an approximately 34-kDa mature peptide that might be secreted into the extracellular region. EsIL-16 mRNA could be detected in all analyzed tissues and was significantly upregulated after immune challenge both in vitro and in vivo. T7 phage display library screening suggested potential binding activity between EsIL-16 and integrin, which was confirmed by coimmunoprecipitation assay. Interestingly, EsIL-16 promoted cell proliferation via integrin ß1 in primary cultured crab hemocytes and Drosophila S2 cells. Furthermore, the interaction between EsIL-16 and integrin ß1 was necessary to efficiently protect the host from bacterial infection. To our knowledge, this study revealed integrin ß1 as a receptor for IL-16 and the function of this interaction in hemocyte proliferation in invertebrates for the first time. These results provide new insights into the regulation of innate immune responses in invertebrates and shed the light on the evolution of ILs within the animal kingdom.

Study on Fabrication and Properties of Graphite/Al Composites by Hot Isostatic Pressing-Rolling Process.

Graphite/Al composites have attracted much attrition due to their excellent thermal properties. However, the improvement of thermal conductivity (TC) is limited by the difficulty in controlling the orientation of graphite and the poor wettability between graphite and aluminum. In this study, a novel process for fabricating the Graphite/Al composites is proposed, which involves fabricating graphite film and aluminum foil into laminate material. Then, taking a rolling method, the fractured and well oriented graphite film can help the composite achieve high TC while maintaining a certain strength. The result reveals that both single and total reduction have a significant influence on the diameter and orientation of the graphite, and by adjusting the process parameters, composites with high TC can be acquired at a relatively low reinforcement volume. This near-net-forming process can directly meet the thickness requirements for electronic packaging and avoids the exposure of graphite to the surface during secondary processing, which is promising to promote the application for high TC Graphite/Al composites in thermal management.

Interfacial Structure of Carbide-Coated Graphite/Al Composites and Its Effect on Thermal Conductivity and Strength.

Graphite/Al composites had attracted significant attention for thermal management applications due to their excellent thermal properties. However, the improvement of thermal properties was restricted by the insufficient wettability between graphite and Al. In this study, silicon carbide and titanium carbide coatings have been uniformly coated on the graphite by the reactive sputtering method, and Graphite/Al laminate composites were fabricated by a hot isostatic pressing process to investigate the influence on thermal conductivity and mechanical properties. The results show that carbide coating can effectively improve the interfacial thermal conductance of SiC@Graphite/Al and TiC@Graphite/Al composites by 9.8 times and 3.4 times, respectively. After surface modification, the in-plane thermal conductivity (TC) of the composites with different volume fractions are all exceeding the 90% of the predictions. In comparison, SiC is more conducive to improving the thermal conductivity of composite materials, since the thermal conductivity of the 28.7 vol.% SiC@Graphite/Al reached the highest value of 499 W/m·K, while TiC is favorable for improving the mechanical properties. The finding is beneficial to the understanding of carbide coating engineering in the Graphite/Al composites.

Distinct vitellogenin domains differentially regulate immunological outcomes in invertebrates.

The classical role of Vitellogenin (Vg) is providing energy reserves for developing embryos, but its roles appear to extend beyond this nutritional function, and its importance in host immune defense is garnering increasing research attention. However, Vg-regulated immunological functions are dependent on three different domains within different species and remain poorly understood. In the present study, we confirmed three conserved VG domains-LPD_N, DUF1943, and VWD-in the Chinese mitten crab (Eriocheir sinensis), highlighting functional similarities of Vg in vertebrates and invertebrates. Of these three domains, DUF1943 and VWD showed definitive bacterial binding activity via interaction with the signature components on microbial surfaces, but this activity was not exhibited by the LPD_N domain. Antibacterial assays indicated that only the VWD domain inhibits bacterial proliferation, and this function may be conserved between different species due to the conserved amino acid residues. To further explore the relationship between Vg and polymeric immunoglobulin receptor (pIgR), we expressed EspIgR and the three E. sinensis Vg (EsVg) domains in HEK293T cells, and coimmunoprecipitation assay demonstrated that only the DUF1943 domain interacts with EspIgR. Subsequent experiments demonstrated that EsVg regulates hemocyte phagocytosis by binding with EspIgR through the DUF1943 domain, thus promoting bacterial clearance and protecting the host from bacterial infection. To the best of our knowledge, our work is the first to report distinct domains in Vg inducing different immunological outcomes in invertebrates, providing new evidence that pIgR acts as a phagocytic receptor for Vg.

The exploration of metal-free catalyst g-C3N4 for NO degradation.

We propose a new metal-free scheme of the reaction between the molecules CO and NO on a g-C3N4 monolayer. We first investigate the electronic properties of the related molecules CO, NO, N2, and CO2 adsorbed g-C3N4 systems, and then figure out the possible reaction pathways. It is shown that all the molecules will be physisorbed above the triangular cavity. Also, we find the NO binding on g-C3N4 is stronger than CO. The NO dissociation will be the rate-determining step of the reaction, and the formation of NCO· intermediate will play a critical role for the reaction process. This research presents a new route of applying g-C3N4 as a catalyst in the NO catalytic degradation reaction.