Rapid label-free impedimetric detection of progesterone enhanced by immunomagnetic bead-based competitive immunoreaction.

Detecting progesterone (P4) concentration in cow serum is essential for monitoring the pregnancy progress after fertilization and is significant for the dairy farming industry and veterinary medicine. This study reports enzyme-free immunomagnetic beads (IMBs)-based competitive immunoassay for detecting P4 by P4-bovine serum albumin (BSA)-modified biosensors. The anti-P4 antibody-conjugated IMBs serve as collectors to capture P4 in undiluted serum samples to prevent the biosensor surface from biosample contamination and as insulated labels to report the electron-transfer resistance signal of electrochemical impedance spectroscopy (EIS) measurement. The IMBs and P4-containing samples were mixed for 15-30 min, capable of obtaining stable P4@IMB complexes. The 0.2-kGauss pulsed magnetic field (PMF) of the 20-s pulse width and 20-s relaxation time applied for 5 min can shorten the immunoreaction time between the P4@IMBs and the P4-BSA-modified biosensor and reduce the IMB's nonspecific adsorption on the biosensor surface. This competitive immunoassay's cut-off value and detection limit were 7.71 ng/mL and 7.33 ng/mL, respectively, which is lower than the serum's P4 plateau concentration (over 8 ng/mL) of dairy cows on days 6-16 of estrus cycles and that in pregnancy. The IMB-based immunoassay combining the PMF attraction and the label-free EIS measurement exhibits promising potential for rapidly detecting P4 in undiluted serum.

The Protective Role of Vitamin E against Oxidative Stress and Immunosuppression Induced by Non-Esterified Fatty Acids in Bovine Peripheral Blood Leukocytes.

High levels of non-esterified fatty acids (NEFAs) during the transition period lead to increased oxidative stress and immunosuppression in cows. Feeding them a vitamin-E-supplemented diet reduces reactive oxygen species (ROS) levels in the blood and diminishes immunosuppression in the transition period. However, whether the restoration of immune cell function occurs through the direct action of vitamin E in cells is still a topic that requires further discussion. Therefore, in this experiment, we aimed to investigate the effect of NEFAs on peripheral blood leukocytes (PBLs) and whether vitamin E mitigates the impact of NEFAs. We employed three groups: (1) blank, (2) NEFA only, and (3) pre-culturing with vitamin E before NEFA treatment (VENEFA). In peripheral blood mononuclear cells (PBMCs), there were no differences in vitamin E content among the three groups. However, in the vitamin E pre-treatment group, the vitamin E levels of polymorphonuclear neutrophils (PMNs) were significantly higher than those in the other two groups. NEFA levels increased malondialdehyde (MDA) levels in PBMCs, but pre-treatment with vitamin E reduced accumulation of MDA levels. Regarding the expression of proinflammatory genes, NEFAs increased the expression of interleukin-1ß in PBMCs and colony-stimulating factor 2 in PMNs. Vitamin E pre-treatment restored the increase in interleukin-1ß levels caused by NEFAs in PBMCs. None of the groups affected the phagocytosis of PMNs. Few studies have confirmed that NEFAs cause oxidative stress in bovine PBLs. In summary, this study found that NEFAs induce oxidative stress in PBLs and alter the expression of inflammation-related genes; meanwhile, vitamin E can reduce some of the effects caused by NEFAs. This result may suggest that vitamin E can assist bovine PBLs in resisting the immune suppression caused by an NEB during the transition period.

Beneficial effect and mechanism of natural resourced polysaccharides on regulating bone metabolism through intestinal flora: A review.

Bone metabolism is an important biological process for maintaining bone health. Polysaccharides of natural origin exert beneficial effects on bone metabolism. Polysaccharide molecules often have difficulty passing through the intestinal cell membrane and are directly absorbed in the gastrointestinal tract. Therefore, polysaccharides may affect intestinal flora and play a role in disease treatment. We performed a comprehensive review of the relevant literature published from 2003 to 2023. We found that several polysaccharides from traditional Chinese medicines, including Astragalus, Achyranthes bidentata and Eucommia ulmoides, and the polysaccharides from several dietary fibers mainly composed of inulin, resistant starch, and dextran could enrich the intestinal microbiota group to regulate bone metabolism. The promotion of polysaccharide decomposition by regulating the Bacteroides phylum is particularly critical. Studies on the structure-activity relationship showed that molecular weight, glycosidic bonds, and monosaccharide composition may affect the ability of polysaccharides. The mechanism by which polysaccharides regulate intestinal flora to enhance bone metabolism may be related to the regulation of short-chain fatty acids, immunity, and hormones, involving some signaling pathways, such as TGF-ß, Wnt/ß-catenin, BMP/Smads, and RANKL. This paper provides a useful reference for the study of polysaccharides and suggests their potential application in the treatment of bone metabolic disorders.

Evaluation indices of the temperature difference of subgrade and the optimization of mitigation measures in cold regions.

With the construction and operation of railways in cold regions, the asymmetric deformation of subgrades due to the difference in the transverse ground temperature has become a prominent issue. A comprehensive evaluation of the transverse ground temperature difference and investigation of the corresponding mitigation measures should be conducted to avoid or minimize the damage resulting from this difference, thereby improving subgrade stability and reducing deformation. In this study, the time history variations in the homogeneity and symmetry indices of the ground temperature at typical instances that reflect the spatial and temporal changes in the temperature difference of the subgrade were proposed as evaluation indices. The feasibility of these evaluation indices was verified through numerical models with different types of anti-frost berms. Subsequently, the numerical models were used to analyze the ground temperature evaluation indices of a subgrade with expanded polystyrene (EPS) insulation board and polyurethane (PU) insulation board at different locations. Additionally, the performances of each mitigation measure in eliminating or reducing the ground temperature difference were assessed and compared. The results show that all the mitigation measures could improve the homogeneity and symmetry of the ground temperature distribution. The maximum mitigation rates for the homogeneity and symmetry are 97.87% and 45.90%, respectively. This study provides a comprehensive evaluation method for the temperature difference of subgrades constructed in cold regions and a theoretical reference for the selection of anti-frost measures in the design, operation, and maintenance of subgrades in cold regions.

Therapeutic effects of scoparone on pilocarpine (Pilo)-induced seizures in mice.

Epilepsy is a common and devastating neurological disorder. Inflammatory processes and apoptosis in brain tissue have been reported in human epilepsy. Scoparone (6,7-dimethoxycoumarin) is an important chemical substance, which has multiple beneficial activities, including antitumor, anti-inflammatory and anti-coagulant properties. In our present study, we attempted to investigate if scoparone could attenuate seizures-induced blood brain barrier breakdown, inflammation and apoptosis. Pilocarpine (Pilo) and methylscopolamine were used to establish acute seizure animal model. Scoparone suppressed the leakage of blood brain barrier, inflammation and apoptosis. In hippocampus and cortex, the expression of inflammation-associated molecules, such as chemokine (CXC motif) ligand 1 (CXCL-1), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), IL-6, hypoxia-inducible factor 1α (HIF-1α), and monocyte chemoattractant protein-1 (MCP-1), were reduced by scoparone through inactivating toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB) pathway. Scoparone reduced apoptotic levels in hippocampus by TUNEL analysis, along with decreased Caspase-3 and PARP cleavage. In addition, phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway in Pilo-induced acute seizures was also inactivated by scoparone. In vitro, we confirmed that scoparone inhibited LPS-caused astrocytes activation as proved by the reduced glial fibrillary acidic protein (GFAP) levels, inflammation and apoptosis, which were at least partly dependent on AKT suppression. The results above indicated that scoparone could relieve pilocarpine (Pilo)-induced seizures against neural cell inflammation and apoptosis.

Characterization of the testicular regeneration potential in premature cockerels.

Previous studies have shown that grafted neonatal chicken testicular tissue can develop and produce functional sperm; however, it was unclear whether regenerative processes or proportional growth caused the re-appearance of spermatogenic tissue. We dissociated testicular tissues, performed subcutaneous auto-transplantation of the re-aggregated cells to castrated cockerels, and monitored the post-surgery development of these transplanted aggregates. We found that these transplanted cell aggregates experienced compensatory growth in the form of a 300-fold increase in size, rather than the 30-fold increase observed in normal testis development. Further, these dissociated testicular cell aggregates restored seminiferous tubule structure and were able to produce testosterone and motile sperm. Therefore, we concluded that the dissociated testicular cells from 11-week-old cockerels retained a strong regenerative potential, as they exhibited compensatory growth, restored destroyed structure, and sustained spermatogenesis.

Risk factors for clopidogrel resistance in patients with ischemic cerebral infarction and the correlation with ABCB1 gene rs1045642 polymorphism.

The aim of the present study was to examine clopidogrel resistance (CR) in patients with ischemic cerebral infarction and its potential association with a single nucleotide polymorphism (SNP; rs1045642) in the ABCB1 gene. Patients with ischemic cerebral infarction received clopidogrel (75 mg/day) for 7 days and were then subjected to a turbidimetric assay to determine platelet aggregation. Patients were then divided into a CR group and a clopidogrel-sensitive (CS) group. Demographic and clinical data between the two groups were compared. Multivariate logistic regression analysis was performed to determine independent risk factors of CR. PCR products were sequenced to assess ABCB1 rs1045642 SNP genotype and allele frequencies in each group. In total, 303 patients were enrolled in the study; this included 51 CR cases (16.83%) and 252 CS cases (83.17%). Several parameters, including hypertension, diabetes, calcium channel blocker (CCB), ß-receptor blocking agent and proton pump inhibitor use, and creatinine, fasting blood glucose, homocysteine (HCY), high-sensitivity C-reactive protein (hs-CRP) and triglyceride levels were significantly higher in the CR group than in the CS group. Diabetes, hs-CRP-increased use of CCBs, and use of ß-blockers were found to be independent risk factors for CR. However, ABCB1 gene rs1045642 polymorphism was not found to be an independent risk factor for CR. In conclusion, CR in ischemic stroke patients is associated with several independent risk factors, including diabetes, hs-CRP-increased use of CCBs, and use of ß-blockers. However, ABCB1 gene rs1045642 polymorphism has no correlation with CR.

Polyurethane/poly(vinyl alcohol) hydrogel coating improves the cytocompatibility of neural electrodes.

Neural electrodes, the core component of neural prostheses, are usually encapsulated in polydimethylsiloxane (PDMS). However, PDMS can generate a tissue response after implantation. Based on the physicochemical properties and excellent biocompatibility of polyurethane (PU) and poly(vinyl alcohol) (PVA) when used as coating materials, we synthesized PU/PVA hydrogel coatings and coated the surface of PDMS using plasma treatment, and the cytocompatibility to rat pheochromocytoma (PC12) cells was assessed. Protein adsorption tests indicated that the amount of protein adsorption onto the PDMS substrate was reduced by 92% after coating with the hydrogel. Moreover, the PC12 cells on the PU/PVA-coated PDMS showed higher cell density and longer and more numerous neurites than those on the uncoated PDMS. These results indicate that the PU/PVA hydrogel is cytocompatible and a promising coating material for neural electrodes to improve their biocompatibility.

Correlations of MUC15 overexpression with clinicopathological features and prognosis of glioma.

The abnormal expression of MUC15, a novel cell membrane-associated mucin, has been reported to predict poor survival in several cancers. The aim of the present study was to examine the expression of MUC15 in glioma and its correlation with clinicopathological features, including the survival of patients with glioma. The mRNA expression level of MUC15 was determined by RT-PCR, quantitative RT-PCR (RT-qPCR) and Western blotting in seven normal brain tissues and seven glioma tissues, respectively. The protein expression level of MUC15 was immunohistochemically detected in paraffin-embedded samples of 317 glioma tissues and 115 noncancerous brain tissues. The association of MUC15 expression levels with the clinicopathologic features and the prognosis was analyzed. The results showed that both mRNA and protein levels of MUC15 were significantly increased in glioma as compared with those in noncancerous brain tissue. Moreover, MUC15 overexpression was positively correlated with the advanced clinical stages of glioam patients (P<0.01). Furthermore, MUC15 expression levels were significantly correlated with the progression of glioma (P<0.001). Survival analysis indicated that glioma patients with higher MUC15 expression had a significantly shorter overall and 5-year survival time than those with low MUC15 expression. Multivariate analysis suggested that MUC15 overexpression was an independent factor for prognosis (hazard risk: 3.216; P=0.009). It was concluded that MUC15 is overexpressed in glioma tissues. Its overexpression correlates with tumor progression and it is a potentially unfavorable prognostic factor for patients with glioma.

MicroRNA-98 induces an Alzheimer's disease-like disturbance by targeting insulin-like growth factor 1.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by extracellular senile plaques and intracellular neurofibrillary tangles. Many microRNAs (miRs) participate in regulating amyloid ß (Aß) formation and the metabolism of tau protein in the process of AD, and some are up-regulated in AD patients or transgenic models of AD. However, the role of miR-98 in AD remains unclear. Here, we showed that the expression of miR-98 was negatively correlated with the insulin-like growth factor 1 (IGF-1) protein level in APP/PS1 mice. MiR-98 target sites in IGF-1 were confirmed by luciferase assay in HEK293 cells. Overexpression of miR-98 in N2a/APP cells down-regulated the IGF-1 protein level and promoted Aß production, whereas inhibition of miR-98 in N2a/APP cells up-regulated the IGF-1 protein level and suppressed Aß production. Furthermore, overexpression of miR-98 in N2a/WT cells increased the phosphorylation of tau, whereas inhibition of miR-98 reduced it. These results suggest that miR-98 increases Aß formation and tau phosphorylation by inhibiting the translation of IGF-1, which might provide a therapeutic strategy for AD.

Polymorphisms of interleukin-1 and interleukin-6 genes on the risk of ischemic stroke in a meta-analysis.

Many epidemiological studies have investigated the associations between polymorphisms of interleukin-1 (IL1) and interleukin-6 (IL6) genes and risk of ischemic stroke (IS), but no conclusions are available because of conflicting results. The aim of this study was to assess the relationships by meta-analysis. The databases of Pubmed, Embase and Wangfang, updated to August 1st, 2011, were retrieved. Odds ratio (OR) and corresponding 95% confidence interval (95% CI) as effect size were calculated by a fixed- or random-effect model. In total, three case-control studies for IL1α-889C/T, eight studies for IL1ß-511C/T, eight studies for IL1-Ra and seven studies for IL6-147G/C were included in this meta-analysis. Combined analysis indicated that IL1ß-511C/T polymorphism was not overall associated with risk of IS [OR (95% CI)=1.22 (0.85-1.87) for TT vs. CC]. However, when subgroup analyses for countries were conducted, the results indicated that T allele was associated with increased risk of IS for Polish and associated with a trend of increased risk of IS for Chinese although it did not reach statistical significance [TT vs. CC: OR (95% CI)=1.97 (1.22-3.17) for Polish and 1.40 (0.99-1.99) for Chinese]. In addition, overall and subgroup analyses indicated that IL1α-889C/T, IL1-Ra and IL6-147G/C polymorphisms were also not associated with risk of IS [OR (95% CI)=1.21 (0.86-1.70) for TT vs. CC of IL1α-889C/T, 1.22 (0.85-1.75) for RN2/RN2 vs. RN1/RN1 for IL1-Ra and 1.09 (0.84-1.40) for G carriers vs. C carriers for IL6-147G/C]. This study inferred that IL1ß-511C/T polymorphism might be moderately associated with increased risk of IS, but no sufficient evidence was available to support any associations between IL1-Ra and IL6-147G/C polymorphisms and IS. We could not draw a conclusion between IL1α-889C/T polymorphism and risk of IS based on the limited data, and further large sample-sized studies were required.

Ultraviolet-blue photoluminescence of ZnSe quantum dots.

Zinc blende, sphericity, monodisperse, high luminescence ZnSe quantum dots (QDs) were synthesized by a one-step mild hydrothermal route with Zn and Se dissolved in aqueous NaOH as the source material. The structure and the morphology of the sample were examined by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results indicated that the products were cubic blende ZnSe ranging from 3.2 to 4.5 nm in size. TEM images showed that the QDs have very good dispersibility and distribution. The characteristic features of the absorption and photoluminescence spectra of ZnSe quantum dots were studied at room temperature. Compared with the bulk ZnSe, the absorption edges and luminescent peaks of ZnSe QDs were blue shifted to higher energies due to the quantum confinement effect. Photoluminescence at ultraviolet excitation showed the strong emission at 390 nm related to the higher excitonic states. ZnSe QDs exhibiting photoluminescence line widths as narrow as 40-60 nm. Meanwhile, we simply explored the theoretical mechanism of luminescence in ZnSe QDs and analogized the relation of various point defect concentrations of ZnSe.

Bibliometric analysis on global Parkinson's disease research trends during 1991-2006.

In 10 years, we will mark the 200th anniversary of the James Parkinson's original description of the disease that now bears his name. This study was to explore an alternative statistical approach to quantitatively and qualitatively assessing current research trends on global Parkinson's disease, using the related literatures from the Institute for Scientific Information (ISI) Web of Science databases during the period of 1991-2006. Articles were concentrated on the analysis by scientific output characters, world collaboration, and the frequency of author keywords used. An exponential regression was applied to model the high correlation between cumulative number of articles and the year. International collaborative articles were more prevalent in recent years than earlier years, and increasing international collaboration would lead to more powerful articles due to the sharing of ideas and workloads, while China, Italy, Spain, and Austria are benefit a lot from the international cooperation. Finally, author keywords were analyzed contrastively, with research trends and recent hotspots provided.

Effect of mild hypothermia on angiogenesis in rats with focal cerebral ischemia.

In the present study, we investigated the effect of mild hypothermia on infarct volume, angiogenesis and brain-derived neurotrophic factor (BDNF) level after stroke. After permanent middle cerebral artery occlusion, mild hypothermia was induced immediately and maintained for 24h. 2,3,5-Triphenyltetrazolium chloride (TTC) staining, laser scanning confocal microscopy (LSCM) and ELISA were performed to assay infarct volume, angiogenesis and BDNF level in the ischemic boundary zone (IBZ), respectively. Compared with normothermic group, mild hypothermia reduced total infarct volume and increased endogenous BDNF level. And the microvessel diameter, the number of vascular branch points and the vessel surface area were significantly increased in the mild hypothermia group. These findings suggest that mild hypothermia enhances angiogenesis in ischemic brain, which might be enhanced in part via BDNF.