Morphology and optical properties of Au-Ag hybrid nanoparticles regulation and its ultra-sensitive SERS immunoassay detection in carbohydrate antigen 19-9.

The development of an ultra-sensitive detection method for carbohydrate antigen 19-9 (CA19-9) is very important for the early diagnosis of pancreatic cancer. In this work, we developed a new strategy to achieve a variety of Au-Ag hybrid nanoparticles from janus to core-satellite which is controlled by the volume of AgNO3 and the concentration of benzimidazolecarboxylic acid (MBIA). With the volume of AgNO3 increased, Au-Ag hybrid nanoparticles changed from janus to core-satellite and the characteristic absorption peak showed two opposite trends. The size and number of Ag islands were determined by the concentration of MBIA. Au-Ag core-satellites nanoparticles with a large number of small-sized Ag have the highest SERS intensity. Then we used them as SERS nanotags and Au-Polystyrene nanospheres modified by captured anti-CA19-9 antibody as solid substrates to realize the ultra-sensitive detection of CA19-9 with a low limit of detection of 1.25 × 10-6 IU/mL and a wide linear range of 1.00 × 10-5 -1.00 × 104 IU/mL. This work not only demonstrates that MBIA and AgNO3 were the key factors in the growth of Au-Ag hybrid nanoparticles from 2D to 3D structure but also supplies an ultra-sensitive detection method for CA19-9 which has a potential practicability in the clinical early diagnoses of pancreatic cancer.

Dietary taurine effect on intestinal barrier function, colonic microbiota and metabolites in weanling piglets induced by LPS.

Diarrhea in piglets is one of the most important diseases and a significant cause of death in piglets. Preliminary studies have confirmed that taurine reduces the rate and index of diarrhea in piglets induced by LPS. However, there is still a lack of relevant information on the specific target and mechanism of action of taurine. Therefore, we investigated the effects of taurine on the growth and barrier functions of the intestine, microbiota composition, and metabolite composition of piglets induced by LPS. Eighteen male weaned piglets were randomly divided into the CON group (basal diet + standard saline injection), LPS group (basal diet + LPS-intraperitoneal injection), and TAU + LPS group (basal diet + 0.3% taurine + LPS-intraperitoneal injection). The results show that taurine significantly increased the ADG and decreased the F/G (p < 0.05) compared with the group of CON. The group of TAU + LPS significantly improved colonic villous damage (p < 0.05). The expression of ZO-1, Occludin and Claudin-1 genes and proteins were markedly up-regulated (p < 0.05). Based on 16s rRNA sequencing analysis, the relative abundance of Lactobacilluscae and Firmicutes in the colon was significantly higher in the LPS + TAU group compared to the LPS group (p < 0.05). Four metabolites were significantly higher and one metabolite was significantly lower in the TAU + LPS group compared to the LPS group (p < 0.01). The above results show that LPS disrupts intestinal microorganisms and metabolites in weaned piglets and affects intestinal barrier function. Preventive addition of taurine enhances beneficial microbiota, modulates intestinal metabolites, and strengthens the intestinal mechanical barrier. Therefore, taurine can be used as a feed additive to prevent intestinal damage by regulating intestinal microorganisms and metabolites.

Intervention Effect of Taurine on LPS-Induced Intestinal Mechanical Barrier Injury in Piglets.

Taurine has the advantages of being safe, highly efficient, chemically stabile, and biologically active, together with having versatile functions. Presently, it is employed as a veterinary feed additive in animal research. The tight junctions that constitute the intestinal epithelial cells are the most critical structures for ensuring regular and uninterrupted digestion and absorption of food by the intestinal mucosa, while at the same time resisting invasions by toxins. The purpose of this study was to investigate the protective effect and mechanism of taurine action on intestinal mechanical barrier function of piglets that were infected with LPS. The results showed that 0.3% taurine inhibits LPS-driven increase in intestinal permeability and intestinal mucosal injury, the rise in the ratio of villus length to crypt depth within the duodenum, jejunum, and ileum, and the significant enhancement in the expression of tight junction protein-related genes. In summary, dietary taurine significantly reduces intestinal mucosal structural damage and intestinal mucosal permeability while increasing gene expression of tight junction proteins of the intestinal mucosa of piglets induced by LPS, thereby enhancing the effect of intestinal mucosal mechanical barriers.

Taurine Prevents LPS-Induced Liver Injury in Weaned Piglets.

This study employed taurine as a feed additive to explore the prophylactic effect of taurine on LPS-induced hepatic injury in piglets. The pathological shifts within hepatic tissue were observed by HE staining. Serum levels of ALT and AST together with SOD, CAT, GSH-PX activity, and MDA serum and liver levels were detected. TUNEL was used to detect apoptosis, while qPCR was employed to detect HO-1, Nrf-2, Bcl2, BAX, Caspase-3, and NF- κB p65 transcriptomic expression levels. TRL4, Caspase-3, Nrf-2, and NF- κB p-p65/NF- κB p65 were detected by Western blot. The results revealed that taurine reduces LPS-induced pathological damage of hepatic tissue and reduces the levels of ALT and AST in pig serum. The transcriptomic expression levels of HO-1 and Nrf-2 were upregulated, and proteomic expression of Nrf-2 was increased. SOD, CAT, and GSH-PX activity was elevated, while MDA content was reduced in serum and liver. The levels of mRNA of BAX and Caspase-3 were downregulated, but mRNA content of Bcl2 was increased, and the protein levels of TRL4, NF-κB p-p65/NF-κB p65, and Caspase-3 were diminished. Overall, the degree of hepatocyte apoptosis was also significantly reduced. In conclusion, taurine reduces LPS-induced injury of piglet liver, while reducing hepatocyte apoptotic levels. These data provide a scientific basis for the selection of animal feed additives and lay a foundation for the healthy and sustainable development of the porcine industry.

Global leadership initiative in malnutrition (GLIM) criteria using hand-grip strength adequately predicts postoperative complications and long-term survival in patients underwent radical gastrectomy for gastric cancer.

BACKGROUND: The present study aims to investigate whether malnutrition defined by the Global Leadership Initiative in Malnutrition (GLIM) criteria using hand-grip strength (HGS) adequately predict postoperative complications and long-term survival in patients underwent radical gastrectomy for gastric cancer in a similar manner to GLIM-defined malnutrition using skeletal muscle index (SMI). METHODS: Patients who underwent radical gastrectomy for gastric cancer from August 2014 to June 2019 were included in this study. Clinical data were prospectively collected. Malnutrition was diagnosed based on the two-step approach following the GLIM criteria. Skeletal muscle mass was assessed using SMI based on abdominal computed tomography (CT) scans, or assessed using HGS. RESULTS: A total of 1359 patients were included in this study, in which 36.2% of the patients were at risk of malnutrition (Nutritional Risk Screening 2002 scores ≥3). The incidence of malnutrition was 28.2% and 27.5% using SMI and HGS, respectively. There was a high agreement between the two criteria of malnutrition (kappa = 0.863, P < 0.001). Both of the two criteria of malnutrition were independently associated with postoperative complications (SMI-GLIM, P = 0.041; HGS-GLIM, P = 0.023), overall survival (P < 0.001, both), and disease-free survival (P < 0.001, both), with similar odds ratio or hazard ratio after adjusting for the same confounding variables. HGS-GLIM malnutrition (P = 0.046) but not SMI-GLIM malnutrition (P = 0.270) was associated with a higher incidence of severe complications. CONCLUSIONS: GLIM criteria using HGS is a useful tool to diagnose malnutrition and has a similar or even better predictive value for postoperative complications and long-term survival after radical gastrectomy for gastric cancer compared with GLIM criteria using SMI.

Heterodimers of metal nanoparticles: synthesis, properties, and biological applications.

Heterodimers of metal nanoparticles consist of two metals, come in many sizes and adopt various shapes. They offer unique properties due to the presence of two metals and have the extraordinary flexibility needed to serve as a multipurpose platform for diverse applications in areas including photonics, sensing, and catalysis. Heterodimer nanoparticles contain different metals that contribute to extraordinary surface plasmon resonance (SPR), surface-enhanced Raman scattering (SERS), and catalytic properties. These properties make them versatile molecules that can be used in intracellular imaging, as antibacterial agents, as photocatalytic and biological macromolecules and for the detection of chemical substances. Moreover, heterodimer nanoparticles are composed of the two metals within larger molecules that provide more choices for modification and application. In this review, we briefly summarize the lesser-known aspects of heterodimers, including some of their properties, and present concrete examples of recent progress in synthesis and applications. This review provides a perspective on achievements and suggests a framework for future research with a focus on the synthesis and application of heterodimers. We also explore the possible applications of heterodimer nanoparticles based on their unique properties.

[Analysis of Changes and Factors Influencing Air Pollutants in the Beijing-Tianjin-Hebei Region During the COVID-19 Pandemic].

A series of strict control measures were imposed in the Beijing-Tianjin-Hebei region in early 2020 to control the spread of COVID-19. These measures have led to a reduction of anthropogenic air pollutants, providing an opportunity to observe the contribution of human activities to local air pollution. In this study, the control period was divided into four stages:the before, early, middle, and later stages. Based on a variety of data including meteorological, traffic, and industrial manufacturing datasets, statistical methods were combined with spatial analysis to evaluate changes in air pollution and associated human impacts during each stage. In addition, suggestions are made for further regional air pollution control in the Beijing-Tianjin-Hebei area. Key results are as follows:① Overall, the AQI and the concentrations of six air pollutants, especially SO2, PM10, and NO2, were lower during control period than during the equivalent period in 2019 (reductions of 26.5%, 24.3%, and 16.9%, respectively). From the before to later stages, pollutants (except O3) showed a downward trend while O3 increased significantly during the before stage (by 76.2%) and the growth rate slowed during the middle and later stages; ②During the prior stage, Beijing experienced two periods with heavy air pollution days as a result of the local accumulation of pollutants, secondary transformation, and regional transport. The concentration of PM2.5 in February was nearly 60% lower than in February 2014 under similar meteorological conditions in Beijing; ③ Following an increase in traffic volume and industrial activity, changes in air pollutants tended to be stable or slightly increase during the middle and later stages of the control period. The grey relation coefficients between thermal radiation intensity anomalies and the main pollutants in heavy industrial cities were greater than 0.6, which means that the control of industrial emissions remains key to controlling air pollution.

The relationship between the GLIM-defined malnutrition, body composition and functional parameters, and clinical outcomes in elderly patients undergoing radical gastrectomy for gastric cancer.

OBJECTIVE: The present study aims to determine the correlations between Global Leadership Initiative in Malnutrition (GLIM)-defined malnutrition and body composition and functional parameters, and to comprehensively analyze the predictive value of GLIM-defined malnutrition for postoperative outcomes in the context of detailed measurement of body composition and functional parameters in elderly patients who underwent radical gastrectomy for gastric cancer. METHODS: Elderly patients (aged ≥65 years) who underwent radical gastrectomy for gastric cancer from August 2014 to June 2019 were included. Malnutrition was diagnosed using the GLIM criteria. Skeletal muscle index (SMI), skeletal muscle density (SMD), subcutaneous fat area (SFA), and visceral fat area (VFA) were analyzed using abdominal computed tomography (CT) images. Handgrip strength and 6-m gait speed were measured. RESULTS: A total of 597 elderly patients were included in this study, in which 45.7% were at risk of malnutrition identified using Nutritional Risk Screening 2002 (NRS 2002), and 34.5% were diagnosed with malnutrition. Patients with malnutrition had lower SMI, SMD, SFA, VFA, lower handgrip strength and gait speed. Low handgrip strength and age ≥80 years were independent risk factors for postoperative complications, rather than GLIM-defined malnutrition. GLIM-defined malnutrition was independently associated with overall survival and disease-free survival after adjusting to the body composition and functional parameters in the multivariate analyses. CONCLUSIONS: GLIM-defined malnutrition was a better predictive factor than single parameters of body composition or physical function for survival in elderly gastric cancer patients. Handgrip strength can be used as a supportive measure to further improve the definition of malnutrition.

Value of muscle quality, strength and gait speed in supporting the predictive power of GLIM-defined malnutrition for postoperative outcomes in overweight patients with gastric cancer.

BACKGROUND: The present study aims to investigate the prognostic value of Global Leadership Initiative in Malnutrition (GLIM)-defined malnutrition in overweight patients who underwent gastrectomy for gastric cancer, and to explore whether the addition of muscle quality, strength and gait speed could improve the predictive power for postoperative outcomes. METHODS: Overweight patients (body mass index (BMI) ≥23 kg/m2) who underwent radical gastrectomy for gastric cancer were included in this study. Malnutrition was diagnosed using the two-step approach following the GLIM criteria. Skeletal muscle mass and quality was assessed using computed tomography (CT) determined skeletal muscle index (SMI) and skeletal muscle density (SMD), respectively. Hand-grip strength and 6-m gait speed were measured before surgery. RESULTS: A total of 587 overweight patients were included, in which 262 patients were identified as having obesity (BMI ≥25 kg/m2). The prevalence of malnutrition was 11.9% and 10.7% for overweight and obese patients, respectively. GLIM-defined malnutrition alone was not predictive for postoperative complications in overweight patients. The addition of low gait speed or muscle quality to GLIM-defined malnutrition led to a significant predictive value for postoperative complications. Low gait speed plus GLIM-defined malnutrition remained significant in the multivariate analysis. GLIM-defined malnutrition was predictive for overall survival (OS) and disease-free survival (DFS). Addition of low gait speed to GLIM-defined malnutrition increased the hazard ratio (HR) for the prediction of OS and DFS (univariate analysis: 2.880 vs. 2.238 for OS, 2.410 vs. 1.937 for DFS; multivariate analysis: 2.836 vs. 1.841 for OS, 2.433 vs. 1.634 for DFS). Addition of low hand-grip strength to GLIM-defined malnutrition led to a higher HR for the prediction of OS (2.144 vs. 1.841) in the multivariate analysis. CONCLUSION: Muscle quality, strength and gait speed added prognostic value to GLIM-defined malnutrition for the prediction of postoperative complications and/or survival in overweight patients who underwent radical gastrectomy for gastric cancer, especially gait speed, which could be incorporated into nutritional assessment protocols.

Antidepressant effect of taurine in chronic unpredictable mild stress-induced depressive rats.

Depression, a psychiatric and dysthymic disorder, severely affects the learning, work and life quality. The main pathogenesis of depression is associated with central nervous system (CNS) dysfunction. Taurine has been demonstrated to exert protective effects on the brain development and can improve learning ability and memory. Our study investigated the antidepressant-like effects of taurine pre-treatment by examining the changes in depression-like behavior, hormones, neurotransmitters, inflammatory factors and neurotrophic factors in the hippocampus of a chronic unpredictable mild stress (CUMS)-induced depressive rat model. Taurine was found to inhibit the decrease of sucrose consumption and prevent the deficiency of spatial memory and anxiety in rats exposed to CUMS, suggesting a preventive effect of taurine on depression-like behavior. Furthermore, the decreased levels of 5-hydroxytryptamine, dopamine, noradrenaline; the increased levels of glutamate, corticosterone; and the decreased expressions of fibroblast growth factor-2, vascular endothelial growth factor and brain derived neurotrophic factor in depressive rats were hindered by taurine pre-administration. However, tumor necrosis factor-α and interleukin-1ß levels were not significantly changed by taurine. The results demonstrated that the anti-depressive effect of taurine may be involved in the regulation of hypothalamic-pituitary-adrenal (HPA) axis and the promotion of neurogenesis, neuronal survival and growth in the hippocampus.

Protoplast fusion between Geotrichum candidium and Phanerochaete chrysosporium to produce fusants for corn stover fermentation.

Lignin impedes the digestion of corn stover when used as an animal feed. Phanerochaete chrysosporium is an efficient lignindegrader. Geotrichum candidum can be used to produce single-cell protein. In this study, protoplasts of the two fungi were prepared and fused. After screening, one of the fusants, Fusant R1, was selected for corn stover fermentation. It decreased lignin from 109 to 54 g/kg and increased protein from 48 to 67 g/kg in corn stover. Comparison with their parental strains indicated that the fusant obtained the lignin-degrading ability from P. chrysosporium and the protein-accumulating ability from G. candidium.