B-nZVI optimization of strength and heavy metal stability of lead-contaminated soil solidified by Portland cement.

Traditional cement solidifying or stabilizing heavy metal-contaminated sites often face issues like alkalinity loss, cracking, and poor long-term performance. Therefore, bentonite-supported nano-zero-valent iron (B-nZVI) was introduced to optimize the remediation effect of cement in this paper. The effects of B-nZVI, ordinary Portland cement (OPC), and B-nZVI + OPC on the chemical stability of heavy metals and the physical strength of lead-contaminated soil were compared using semi-dynamic leaching methods, BCR tests, unconfined strength analysis, and micro-assisted analysis. Results demonstrated that the addition of B-nZVI effectively enhanced the remediation efficacy of OPC on lead-contaminated soil. The combination of B-nZVI and OPC exhibited a synergistic repair effect, offering superior physical strength and chemical stability for lead remediation. B-nZVI facilitated the adsorption and enrichment of Pb2+, thereby reducing oxidizable lead and enhancing short-term stabilization. Meanwhile, OPC precipitation and silicate gelling stabilized exchangeable lead into the residual form, necessitating repeated hydration gelling. Additionally, B-nZVI's sealing effect via water absorption delayed the leaching of exchangeable lead, thereby reducing lead migration. Even with only 1% B-nZVI added to the 12% OPC base, the leaching amount of Pb2+ decreased significantly from 67.6 to 6.59 mg/kg after 7 d of curing. The unconfined strength of contaminated soil treated with the composite solidifying agent for 7 d was 12.87% higher than that of OPC alone, and for 28 d, it was 36.48% higher. This optimization scheme presents a promising approach for effective and sustainable remediation of heavy metal-contaminated sites.

Protective Effect of Curcumin Against Oxidative Stress-Induced Injury in Rats with Parkinson's Disease Through the Wnt/ ß-Catenin Signaling Pathway.

BACKGROUND/AIMS: The study aimed to investigate the protective effect of curcumin against oxidative stress-induced injury of Parkinson's disease (PD) through the Wnt/ß-catenin signaling pathway in rats. METHODS: The successfully established PD rat models and normal healthy rats were randomly assigned into the 6-hydroxydopamine (6-OHDA), the curcumin (Cur) and the control groups. Immunohistochemistry was used to detect the positive expression of tyrosine hydroxylase (TH), dopamine transporter (DAT) and glial fibrillary acidic protein (GFAP). Deutocerebrum primary cells were extracted and classified into the control, 6-OHDA, Cur (5, 10, 15 µmol/L), Dickkopf-1 (DKK-1) and Cur + DKK-1 groups. MTT assays, adhesion tests and TUNEL staining were used to assess cell viability, adhesion and apoptosis, respectively. Western blotting and qRT-PCR were used to examine the protein and mRNA expressions of Wnt3a and ß-catenin and the c-myc and cyclinD1 mRNA expressions. RESULTS: TH and DAT expressions in the Cur group were elevated and GFAP was reduced compared with the 6-OHDA group. Curcumin enhanced viability, survival and adhesion and attenuated apoptosis of deutocerebrum primary cells by activating the Wnt/ß-catenin signaling pathway. Higher Wnt3a and ß-catenin mRNA and protein expressions and c-myc and cyclinD1 mRNA expressions, enhanced superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) contents, decreased malondialdehyde (MDA) content and elevated mitochondrial membrane potential (∆ψm) were found in the 10 and 15 µmol/L Cur groups compared with the 6-OHDA group. However, opposite tendencies were found in the Cur + DKK-1 group compared to the 10 µmol/L Cur group. CONCLUSION: This study suggests that curcumin could protect against oxidative stress-induced injury in PD rats via the Wnt/ß-catenin signaling pathway.

Curcumin-Activated Mesenchymal Stem Cells Derived from Human Umbilical Cord and Their Effects on MPTP-Mouse Model of Parkinson's Disease: A New Biological Therapy for Parkinson's Disease.

BACKGROUND: The aim of this study was to investigate the effects of human umbilical cord mesenchymal stem cell activated by curcumin (hUC-MSCs-CUR) on Parkinson's disease (PD). hUC-MSCs can differentiate into many types of adult tissue cells including dopaminergic (DA) neurons. CUR could protect DA neurons from apoptosis induced by 6-hydroxydopamine (6-OHDA). Therefore, we used the hUC-MSCs activated by CUR for the treatment of PD in an animal model. METHODS: The hUC-MSCs-CUR was transplanted into the MPTP-induced PD mouse models via the tail vein. We found that hUC-MSCs-CUR significantly improved the motor ability, increased the tyrosine hydroxylase (TH), dopamine (DA), and Bcl-2 levels, and reduced nitric oxide synthase, Bax, and cleaved caspase 3 expression in PD mice. The supernatant of hUC-MSCs-CUR (CM-CUR) was used to stimulate the SH-SY5Y cellular model of PD; cell proliferation, differentiation, TH, and neuronal-specific marker microtubular-associated protein 2 (MAP2) expressions were examined. RESULTS: Our data showed that CM-CUR significantly promoted cell proliferation and gradually increased TH and MAP2 expression in SH-SY5Y PD cells. The beneficial effects could be associated with significant increase of rough endoplasmic reticulum in the hUC-MSCs-CUR, which secretes many cytokines and growth factors beneficial for PD treatment. CONCLUSIONS: Transplantation of hUC-MSCs-CUR could show promise for improving the motor recovery of PD.

[Study of mechanism on differentiation of marrow stroma cells into neuron-like cells induced by Ciwujia injection in vitro].

OBJECTIVE: To study whether the nuclear factor-kappa B (NF-kappaB) play a role in differentiation of marrow stroma cells (MSCs) into neuron-like cells induced by Ciwujia injection in vitro. METHOD: Rats were randomly divided into control group and Ciwujia induced group. Cell morphology was observed with invert microscope; MSCs phenotype, expression of neural marker protein and nucleus translocation of NF-kappaB subunit RelA (p65) after induction were observed by immunofluorescence; Expression of IkappaBalpha in Ciwujia induced group and control group was detected by Western blot. RESULT: The decreased volume of some MSCs, strengthened three-dimensional structure and shrinkage of cell body with formation of spire or round was observed after induction by Ciwujia for 1 hour. After 5-hour exposure to Ciwujia, changes in the morphology of MSCs were as follows: appearance of more triangular or round shapes cells, retraction of microfilament in MSCs, formation of slender process from pseudopod with reticular structure, exfoliation and necrosis. After 7-day induction, most MSCs became triangular and round shapes, exhibiting a typical neuronal structure. Immunofluorescence method showed that nestin expression displayed intensively positive in Ciwujia group at 1 hour, and still remain positive at 7 day. However, beta-III Tubulin expression was weakly positive at 1 hour and intensive positive at 3 and 5 hour. It was still positive at 7 day. NSE expression was weakly positive at 3 hour and intensive positive at 5 hour and 7 day. GFAP expression was negative. However, in the control group, every expression of marker protein was negative or weakly positive. Expression of p65 was in cytoplasm. Western blot method showed IkappaBalpha protein relative IA was 1.000 before induction. It was 0.4556 +/- 0.1008 after induction in Ciwujia group and decreased significantly than before induction (P < 0.01). It was 0.0296 +/- 0.0099 after induction in control group and decreased significantly than before induction and in Ciwujia group (P < 0.01). CONCLUSION: The data showed that MSCs can induce differentiation into neuron-like cells by Ciwujia, and Ciwujia could inhibit the translocation of NF-kappaB from the cytoplasm to the nucleus, which may be relate to the differentiation of MSCs into neuron-like cells.

SPK1-transfected UCMSC has better therapeutic activity than UCMSC in the treatment of experimental autoimmune encephalomyelitis model of Multiple sclerosis.

Multiple Sclerosis (MS), is a chronic inflammatory autoimmune disorder of the central nervous system that leads to chronic demyelination with axonal damage and neuronal loss. Mesenchymal stem cells (MSCs) represent a promising therapeutic approach for MS. In the current study, we investigated the effects of MSCs derived from the human umbilical cord (UCMSC) transfected by sphingosine kinase 1 (SPK1) gene. All the results showed that transplantation of UCMSCs gene modified by SPK1 (UCMSC-SPK1) dramatically reduce the severity of neurological deficits of the experimental autoimmune encephalomyelitis (EAE) mice, paralleling by reductions in demyelination, axonal loss, and astrogliosis. UCMSC-SPK1 transplantation also could inhibit the development of natural killer (NK) responses in the spleen of EAE mice, and increase the ratio of CD4+ CD25+ FoxP3+ (Treg) T cells. Furthermore, we described that a shift in the cytokine response from Th1/Th17 to Th2 was an underlying mechanism that suppressed CNS autoimmunity. UCMSCs transfected by SPK1 gene potentially offer a novel mode for the treatment of MS, and the specific mechanism of SPK1 in treating MS/EAE.

Expression and significance of angiostatin, vascular endothelial growth factor and matrix metalloproteinase-9 in brain tissue of diabetic rats with ischemia reperfusion.

OBJECTIVE: To discuss the expression and significance of angiostatin, vascular endothelial growth factor and matrix metalloproteinase-9 in the brain tissue of diabetic rats with ischemia reperfusion. METHODS: A total of 60 male Wistar rats were randomly divided into the normal group, sham group, diabetic cerebral infarction group and single cerebral infarction group according to the random number table, with 15 rats in each group. The high sucrose diet and intraperitoneal injection of streptozotocin were performed for the modeling of diabetic rats, while the thread-occlusion method was employed to build the model of cerebral ischemia reperfusion. The immunohistochemical staining was performed to detect the expression of angiostatin, vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) in the brain tissue. RESULTS: The expression of angiostatin after the reperfusion in the brain tissue of rats in the single cerebral infarction group and diabetic cerebral infarction group was increased 6 h after the reperfusion, reached to the peak on 1 d and then decreased gradually. The expression of angiostatin in the diabetic cerebral infarction group 6 h, 1 d, 3 d and 7 d after the reperfusion was significantly higher than that in the single cerebral infarction group (P < 0.05). VEGF began to be increased 1 h after the reperfusion in the single cerebral infarction group and diabetic cerebral infarction group, reached to the peak at 6 h and then decreased gradually. The expression of VEGF in the diabetic cerebral infarction group at each time point after the reperfusion was significantly lower than that in the single cerebral infarction group (P < 0.05). MMP-9 began to be increased 1 h after the reperfusion in the single cerebral infarction group and diabetic cerebral infarction group, reached to the peak on 1 d and then decreased gradually. The expression of MMP-9 in the diabetic cerebral infarction group at each time point after the reperfusion was significantly higher than that in the single cerebral infarction group (P < 0.05). CONCLUSIONS: The high glucose environment in which the diabetic cerebral infarction is occurred is to induce the formation of MMP-9 at first and then activate and increase the expression of angiostatin. Afterwards, the expression of VEGF is inhibited, resulting in the poor angiogenesis after cerebral infarction, which thus makes the injury of brain tissue after cerebral infarction even worse than the non-diabetes mellitus.

[Effect of non-contact coculture on bone marrow stromal cells and neural stem cells].

OBJECTIVE: To observe the effect of non-contact coculture on bone marrow stromal cells (MSCs) and neural stem cells (NSCs) in neural stem cell culture medium. METHODS: MSCs and NSCs were cultured in non-contact coculture in Transwell plate, and cell morphology and immunocytochemical profile were investigated. RESULTS: In the coculture, the NSCs showed adhering growth and extended long processes, and the migrating cells formed a network of cells within 7 days. The cells differentiated into neurons, astrocytes and oligodendrocytes as shown by immunocytochemistry. Most of the MSCs grew in a non-adherent manner, giving rise to large spherical cell masses which expressed neuronal, astrocyte, and oligodendrocyte phenotypes. In the control group, the NSCs grew in suspension, some of MSCs formed small non-adherent spherical cell masses, while some cells showed adherent growth. CONCLUSION: MSCs and NSCs in the non-contact coculture can mutually promote the cell differentiation into neural cells in neural stem cell culture medium, indicating that both MSCs and NSCs can secrete some neurotrophic factors to provide a microenvironment suitable for survival and differentiation for each other.

[Effects of Ciwujia in inducing marrow stromal cell differentiation into neuron-like cells in vitro].

OBJECTIVE: To study the effect of the traditional Chinese herbal drug Ciwujia in inducing the differentiation of marrow stromal cells (MSCs) into neuron-like cells. METHODS: Rat MSCs isolated from the whole bone marrow were amplified by adherent culture in vitro and induced to differentiate into neuron-like cells using serum-free DMEM/F12 containing Ciwujia. The protein and mRNA expressions of nestin, beta-Tubulin III and glial fibrillary acidic protein (GFAP) in the differentiated cells were detected by indirect immunofluorescence method, Western blotting and RT-PCR. RESULTS: The third-passage MSCs showed positive expression rates for CD44 and CD54 beyond 90% with decreased CD14 expression rate to 2.37%. Induction by Ciwujia of the MSCs resulted in cell body shrinkage and protrusion of the cell processes resembling those of neurons. The differentiated cells were positive for nestin and beta-Tubulin III expression and negative for GFAP as shown by immunofluorescence assay, Western blotting and RT-PCR. CONCLUSION: Ciwujia can induce the differentiation of rat MSCs into neuron-like cells in vitro.

Temporal cortex participates in spontaneous perceptual reversal.

The Necker cube is perceived as two distinct three-dimensional forms; participants experience alternation between two mutually exclusive perceptions. Perceptual dominance for one form tends to be maintained when the visual stimulus is intermittently removed. The effect is enhanced with the Necker lattice (an array of Necker cubes). Neural processes underlying perceptual reversal and stabilization are unknown. Functional MRI was used to investigate the brain regions involved. Regional activation differed between endogenous and stimulus-driven perceptual reversals, and between reversal and stabilization. Our results indicated that the right anterior portion of superior temporal sulcus is likely to be involved in perceptual stabilization (perceptual memory), whereas reversal is modulated by destabilizing influences from the right frontal lobe.

[Epidemiological investigation on natural infection to Borna disease virus (BDV) among horses in Yili, Xinjiang].

OBJECTIVE: To investigate the epidemiological pattern of Borna disease virus (BDV) infection in horses and to analyze the phylogenetic tree of derived BDV in Yili, Xinjiang. METHODS: We established a modified nested RT-PCR (nRT-PCR) to detect BDV p24 segment in peripheral blood mononuclear cells (PBMCs) and brain tissues of 120 horses in Yili, Xinjiang. Positive products were analyzed by sequencing and homology analysis. RESULTS: The positive rate of BDV infection was 2.5% in both PMBCs and brain tissues at the same time. The gene sequence revealed in positive PCR samples was more than 93%, identical to that of BDV derived from horses in other countries. We also noticed a high degree of identity (> 98%) to standard strain He/80 in gene sequence of positive PCR samples. CONCLUSION: Our study found the presence of BDV natural infection in horses in Yili. The endemic BDV had a high degree of identity to standard strain He/80.