Study on influence of external factors on the electrical excitability of PC12 quasi-neuronal networks through Voltage Threshold Measurement Method.

The aim of this paper was to investigate the influence of four different external factors (acetylcholine, ethanol, temperature and lidocaine hydrochloride) on PC12 quasi-neuronal networks by multielectrode-array-based Voltage Threshold Measurement Method (VTMM). At first, VTMM was employed to measure the lowest amplitude of the voltage stimulating pulses that could just trigger the action potential from PC12 quasi-neuronal networks under normal conditions, and the amplitude was defined as the normal voltage threshold (VTh). Then the changes of the VTh of PC12 quasi-neuronal networks treated by the four external factors were tested respectively. The results showed the normal VTh of PC12 quasi-neuronal networks was 36 mV. The VTh has negative correlation with the concentration of acetylcholine and has positive correlation with the concentration of ethanol. The curves of the correlation of the VTh with temperature and the concentration of lidocaine hydrochloride were U-shaped and Λ-shaped respectively. Comparing with our earlier studies on hippocampal neuronal networks and hippocampal slices, PC12 quasi-neuronal networks not only had the same typical voltage threshold characteristic, but also had similar changes on electrical excitability when treated by the four external factors mentioned above. Therefore, the rapid-formed PC12 quasi-neuronal networks could replace neuronal networks in proper conditions, and VTMM could be used to analyze the influence of external factors on the electrical excitability of PC12 quasi-neuronal networks.

Inhibition of drug-metabolizing enzymes by Jingyin granules: implications of herb-drug interactions in antiviral therapy.

Jingyin granules, a marketed antiviral herbal medicine, have been recommended for treating H1N1 influenza A virus infection and Coronavirus disease 2019 (COVID-19) in China. To fight viral diseases in a more efficient way, Jingyin granules are frequently co-administered in clinical settings with a variety of therapeutic agents, including antiviral drugs, anti-inflammatory drugs, and other Western medicines. However, it is unclear whether Jingyin granules modulate the pharmacokinetics of Western drugs or trigger clinically significant herb-drug interactions. This study aims to assess the inhibitory potency of the herbal extract of Jingyin granules (HEJG) against human drug-metabolizing enzymes and to clarify whether HEJG can modulate the pharmacokinetic profiles of Western drug(s) in vivo. The results clearly demonstrated that HEJG dose-dependently inhibited human CES1A, CES2A, CYPs1A, 2A6, 2C8, 2C9, 2D6, and 2E1; this herbal medicine also time- and NADPH-dependently inhibited human CYP2C19 and CYP3A. In vivo tests showed that HEJG significantly increased the plasma exposure of lopinavir (a CYP3A-substrate drug) by 2.43-fold and strongly prolonged its half-life by 1.91-fold when HEJG (3 g/kg) was co-administered with lopinavir to rats. Further investigation revealed licochalcone A, licochalcone B, licochalcone C and echinatin in Radix Glycyrrhizae, as well as quercetin and kaempferol in Folium Llicis Purpureae, to be time-dependent CYP3A inhibitors. Collectively, our findings reveal that HEJG modulates the pharmacokinetics of CYP substrate-drug(s) by inactivating CYP3A, providing key information for both clinicians and patients to use herb-drug combinations for antiviral therapy in a scientific and reasonable way.

Conjoint analysis of influence of LC-HCL and Mor-HCL on Vth and neurite length in hippocampal neuronal network.

Lidocaine hydrochloride (LC-HCl) and morphine hydrochloride (Mor-HCl) are two kinds of most prevalently used anesthetics. However, their influences on electrical excitability of hippocampal neuronal networks and hippocampal brain slices were rarely studied. Previously, our group have assessed the influence of acetylcholine, alcohol and temperature change on the excitability of neural networks with the so-called Voltage Threshold Measurement Method (VTMM) based on microelectrode array (MEA). In this paper, we will study the influence of LC-HCl and Mor-HCl on the electrical excitability of neural networks and the morphological features of neurons, and discuss the relations between the changes of electrical excitability of neural networks and the morphological changes of neurons. The results of VTMM showed: The voltage threshold (VTh) of hippocampal neuronal networks and hippocampal brain slices first increased and then decreased as the LC-HCl concentration increased. The VTh of hippocampal neuronal networks and hippocampal brain slices increased as the Mor-HCl concentration increased. The results of HCS experiments showed: The neurite length change of cultured hippocampal neuronal networks increased first and then decreased with increased LC-HCl concentration, but decreased as the Mor-HCl concentration increased. The combined analysis of VTMM and HCS experiments showed that under effects of the two drugs, the VTh and the hippocampal neurite length were strongly negatively correlated.

Geographical Origin Classification of Chinese Wines Based on Carbon and Oxygen Stable Isotopes and Elemental Profiles.

ABSTRACT: Wines from different regions have different qualities due to the impact of geographical location and climate. The sale of inferior wines seriously violates the fair-trade rights of consumers. This article provides an elemental analysis classification method for verifying the geographical origin of wines in the People's Republic of China. Inductively coupled plasma mass spectrometry, liquid chromatography isotope ratio mass spectrometry, and an isotope ratio mass spectrometer were used to analyze 142 wine samples collected from Helan Mountain, Xinjiang, Yunchuanzang, the Yanhuai Valley, and the Hexi Corridor regions. The data included elemental profiles, carbon isotope ratios (δ13C), and oxygen isotope ratios (δ18O). The results of multivariate analysis revealed that the geographical origin of wine is closely related to variations in elemental profiles and isotope ratios. Introducing δ18O and the elements Li, Mn, Ag, In, Th, Ta, and Re into the discriminant model yielded correct classification rates of the linear discriminant model of 90.8% for the training set and 87.3% for the test set.

Distinctive functional deficiencies in axonal conduction associated with two forms of cerebral white matter injury.

AIMS: This study determines whether assessment with compound action potentials (CAPs) can distinguish two different forms of cerebral white matter injury at the functional levels. METHODS: A pure demyelination model was induced in C57/BL6 adult mice by dietary supplementation of cuprizone (0.2%) for 6 weeks. Callosal L-N5-(1-Iminoethyl) ornithine (L-NIO) hydrochloride (27 mg/mL) was injected into the corpus callosum (CC) to induce a focal white matter stroke (WMS), resulting in both demyelination and axonal injury. White matter integrity was assessed by performing CAP recording, electron microscopy, and immunohistological and luxol fast blue (LFB) staining. RESULTS: Immunohistological and electron microscopic analyses confirmed the induction of robust demyelination in CC with cuprizone, and mixed demyelination and axonal damage with L-NIO. Electrophysiologically, cuprizone-induced demyelination significantly reduced the amplitude of negative peak 1 (N1), but increased the amplitude of negative peak 2 (N2), of the CAPs compared to the sham controls. However, cuprizone did not affect the axonal conduction velocity. In contrast, the amplitude and area of both N1 and N2 along with N1 axonal conduction velocity were dramatically decreased in L-NIO-induced WMS. CONCLUSIONS: Concertedly, parameters of the CAPs offer a novel functional assessment strategy for cerebral white matter injury in rodent models.

Quantitative evaluation of extrinsic factors influencing electrical excitability in neuronal networks: Voltage Threshold Measurement Method (VTMM).

The electrical excitability of neural networks is influenced by different environmental factors. Effective and simple methods are required to objectively and quantitatively evaluate the influence of such factors, including variations in temperature and pharmaceutical dosage. The aim of this paper was to introduce 'the voltage threshold measurement method', which is a new method using microelectrode arrays that can quantitatively evaluate the influence of different factors on the electrical excitability of neural networks. We sought to verify the feasibility and efficacy of the method by studying the effects of acetylcholine, ethanol, and temperature on hippocampal neuronal networks and hippocampal brain slices. First, we determined the voltage of the stimulation pulse signal that elicited action potentials in the two types of neural networks under normal conditions. Second, we obtained the voltage thresholds for the two types of neural networks under different concentrations of acetylcholine, ethanol, and different temperatures. Finally, we obtained the relationship between voltage threshold and the three influential factors. Our results indicated that the normal voltage thresholds of the hippocampal neuronal network and hippocampal slice preparation were 56 and 31 mV, respectively. The voltage thresholds of the two types of neural networks were inversely proportional to acetylcholine concentration, and had an exponential dependency on ethanol concentration. The curves of the voltage threshold and the temperature of the medium for the two types of neural networks were U-shaped. The hippocampal neuronal network and hippocampal slice preparations lost their excitability when the temperature of the medium decreased below 34 and 33°C or increased above 42 and 43°C, respectively. These results demonstrate that the voltage threshold measurement method is effective and simple for examining the performance/excitability of neuronal networks.

[Progress on magnetic resonance imaging for evaluating the articular cartilage of the knee joint].

The reasonable selection of magnetic resonance imaging(MRI) scan sequence and parameters is very important for the objective evaluation of the results of clinical study and high quality imaging. The semi quantitative scoring system of total knee joint including Whole Organ Magnetic Resonance Imaging Score, Boston Leeds Osteoarthritis Knee Score, MRI Osteoarthritis Knee Score, Cartilage Repair Osteoarthritis Knee Score and so on. They can fully evaluate the imaging changes of various organs during the development of knee osteoarthritis. With the continuous development of MRI technology, the morphological and physiological changes of articular cartilage can be quantitatively assessed. T2 mapping, Diffusion Weighted Imaging, and delayed Gadolinium-Enhanced MRI of Cartilage can be quantitatively monitoring changes in cartilage matrix components. These quantitative and semi quantitative evaluation techniques are helpful to detect OA in its early stage, guide clinical early intervention, and also provide the possibility for the accurate evaluation of the therapeutic effect.

Changes of mesenchymal stromal cells mobilization and bone turnover in an experimental bone fracture model in ovariectomized mice.

OBJECTIVE: The aim of this study was to characterize the mesenchymal stromal cells (MSCs) and endothelial progenitor cells (EPCs) mobilization, and bone turnover in osteoporotic fracture healing in ovariectomized mice. METHODS: In total, 112 female C57/BL mice were divided into two groups. The first group was sham-operated (SO), and the other group was ovariectomized (OVX). After three weeks, the right femora of the mice were fractured under anesthesia and internally fixed with steel pin. Peripheral blood and bone marrow were was collected for flow cytometry analysis, at 0 hours (h), 12 h, 24 h, 72 h and 168 h after fracture. MSCs and EPCs levels were assessed using cell surface antigens in different combinations (CD44+ CD34-CD45-, and CD34+ KDR+CD45-) by flow cytometry. At 0, 14, 28 and 42 days after fracture, sera were assayed for circulating levels of procollagen type I-N-terminal propeptide (P1NP) and C-terminal telopeptide of type I-collagen (CTX) by ELISA. Femurs were harvested at 2 weeks and 6 weeks after fracture for X-ray radiography, micro-computed tomography (micro-CT) and histology. RESULTS: Our results showed that bone marrow and peripheral blood MSCs numbers of the OVX mice were significantly lower than the SO mice, at 12 h, 24 h and 72 h after fracture. In addition, circulating P1NP and CTX levels of the OVX mice were significantly higher than the SO mice, at 2 and 4 weeks. CONCLUSION: Results of the present study revealed disorders of bone marrow MSCs mobilization and bone turnover may partially account for the delay of osteoporotic fracture healing.

Bufalin exerts inhibitory effects on IL-1ß-mediated proliferation and induces apoptosis in human rheumatoid arthritis fibroblast-like synoviocytes.

Rheumatoid arthritis fibroblast-like synoviocytes (RAFLSs) proliferate abnormally and resist apoptosis. Bufalin inhibits cell proliferation and induces apoptosis in human cancer cells. In this study, we explored the effects of bufalin on interleukin-1beta (IL-1ß)-induced proliferation and apoptosis of RAFLSs. The cell proliferation and apoptosis were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay and annexin V/propidium iodide staining, respectively. Bufalin dose-dependently inhibited IL-1ß-induced RAFLS proliferation. Mechanistically, bufalin decreased the activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB), both of which are involved in IL-1ß-mediated RAFLS proliferation. Moreover, bufalin induced apoptosis and mitochondrial damage of RAFLSs, which was associated with Bcl-2 downregulation, Bax upregulation, mitochondrial cytochrome c release, and enhanced cleavages of caspase-3 and poly-(ADP-ribose) polymerase. Collectively, our results reveal that bufalin suppresses IL-1ß-induced proliferation of RAFLSs through MAPK and NF-κB signaling pathways and induces RAFLS apoptosis via the mitochondria-dependent pathway.

Liver X receptor α inhibits osteosarcoma cell proliferation through up-regulation of FoxO1.

BACKGROUND: Osteosarcoma is the most common primary bone malignancy of adolescents and young adults. METHODS: We analyzed liver X receptor α (LXRα) mRNA expression in 16 pairs of human osteosarcoma tissues and adjacent noncancerous tissues. Moreover, we investigated LXRα's potential role in regulating cell proliferation in Saos-2 and U2OS cells. RESULTS: We found that activation of LXRα, a member of nuclear receptor, was able to inhibit cell proliferation in Saos-2 and U2OS cells. At the molecular level, our results further revealed that expression of tumor suppressor gene, FoxO1, was up-regulated by LXRα activation. LXRα activates FoxO1 transcription through a direct binding on its promoter region. CONCLUSION: LXRα acts as a tumor suppressor for osteosarcoma, which may offer a new way in molecular targeting cancer treatment.

Experimental study on topical treatment of diabetic skin ulcers with yi medicine "yi bu a jie" extract.

OBJECTIVE: To study the role and mechanism of the Yi medicine, Yi Bu A Jie () extract, in topical treatment of diabetic skin ulcers, with a view to finding a breakthrough natural drug for the prevention and treatment of diabetic skin ulcers. METHODS: A model of diabetic skin ulcers in Kunming mice was developed. Yi Bu A Jie was extracted in a Soxhlet extractor. Two different concentrations of the extract (0.005 mg/mL and 0.01 mg/mL) were applied to the wound of diabetic skin ulcers once every 3 days, and local skin appearance and histopathological changes were observed. RESULTS: The shortest healing time was 25.25±2.06 day with a low concentration (P=0.0037 compared with the high concentration group, 33.14±2.21 day; P=0.0082 compared with control group, 28.21±2.14 days). The longest healing time was in the high concentration group (P=0.0025 compared with the control group). In both groups, a large number of inflammatory neutrophil cells were exuded during the experimental period. In the low concentration group, capillary-rich granulation tissue and actively growing fibroblasts appeared in the wound, while there was much necrotic tissue in the high concentration group. CONCLUSION: Yi Bu A Jie extract has an inhibitory effect on diabetic skin ulcers in mice, and the low concentration is more suitable.

Why are S(n)N4 (n = 1-4) species "missing"? Answers in a broader theoretical context of binary S-N compounds.

Computational investigations of the thermochemical stability and kinetic persistence of binary S(x)N(y) compounds, SN(2), S(2)N(2), S(3)N(2), S(4)N(2), SN(4), S(2)N(4), S(3)N(4), and S(4)N(4), explain why some S(x)N(y) stoichiometries exist but not others. There is no direct link between the Hückel 4n + 2 π-electron count rule and the computed heats of formation (per atom) of the lowest-energy neutral S(n)N(4) (n = 1-4) isomers, but kinetic persistence often is paramount. Thus, the five lowest-energy S(2)N(4) minima at the B3LYP/6-311+G(3df) density functional theory level (A1-A5) all not only have high computed heats of formation [Δ(f)H°(0 K) > 131 kcal/mol or >22 kcal/mol/atom] but also have low dissociation barriers (less than 21.5 kcal/mol for the most favorable pathways). For comparison, the persistent (but potentially explosive!) cyclic S(2)N(2)-c has about the same high heat of formation (per atom) as the least unfavorable S(2)N(4) isomer, but its barrier to ring opening (51 kcal/mol) is much higher. Although aromatic, both SN(4) (6π electron) and S(3)N(4) (10π electron) have low dissociation barriers and, like S(2)N(4), are also absent from the S-N binary family.

Three-dimensional alteration of microvasculature in a rat model of traumatic spinal cord injury.

Acute spinal cord injury (SCI) always leads to severe destruction of the microvascular networks. To investigate the three-dimensional (3D) alterations of microvasculature following SCI, we utilized an established rat SCI model. Based on the hypothesis that the spinal cord would undergo reorganization and postinjury modification of the vascular networks after SCI, we reconstructed the normal and injured angioarchitecture using micro-CT images of silicone rubber microsphere-perfused specimens. Several morphometric parameters were used to study the 3D vascular alterations in the SCI rat model, including the casting-based vessel volume fraction, connectivity density, separation, thickness and thickness distribution. Our results indicated that the microvascular spatial conformations were significantly different between the normal and injured spinal cord segments. The morphometric changes showed an increase of the vessel volume fraction and separation and a decrease of vessel connectivity density during the vascular healing process after SCI. Our results may contribute to elucidation of the mechanisms of compensatory vascular reconstitution in traumatized spinal cord. The method used here has the potential to improve our understanding of changes in the spatial architecture of vascular networks after SCI compared to the conventional histomorphology techniques. In summary, we developed a new methodology to analyze neurovascular pathology based on 3D vascular network patterns and features in an experimental rat SCI model. This technique could be used as a complementary tool to investigate the efficacy and side effects of therapeutic drugs or rehabilitation regimens.

[Experimental study on the mechanism of icariin improving human osteoblasts proliferation and the expression of OPG protein].

OBJECTIVE: To establish the human osteoblasts culture system in vitro, observe the effects of icariin on human osteoblasts proliferation and expression of OPG protein, and to explore the mechanism of promoting bone formation about human osteoblast in icariin. METHODS: The femoral cancellous bone pieces were obtained from the operation. The enzyme digestion method was used for culturing. The third passage of human osteoblast was taken for experiments. The cells were divided into four groups, the control group was treated with 15% NCS-DMEM-F12 (1:1), the experimental groups were respectively treated with 10(-6), 10(-8), 10(-10) mol/L icariin. The MTT method was used to observe the proliferation of human osteoblast on 1, 3, 5, 7, 9 d; in 8, 10, 12 d, western blot was used to determine the expression of OPG protein on human osteoblast. RESULTS: 1) Results of MTT: the icariin promoted the proliferation of human osteoblast. There was a concentration-response relation,while with the concentration of icariin increased, the ability was more obvious. There was statistically difference between 10(-6) mol/L icariin group (0.402 +/- 0.033) and the control group (0.268 +/- 0.031) (P<0.05). In the timely research, as the time prolong, the number of human osteoblast were more. At the fifth day, the human osteoblast entered rapid growth period, and access the growth platform stage; the icariin began to promote the proliferation of human osteoblast from the fifth day, which almost maintained to the 7th day and the 9th day, and most obvious in the 9th day. There was statistically difference between 10(-6) mol/L icariin group (0.402 +/- 0.033) and the control group (0.268 +/- 0.031) at the 9th day. (The results of OPG protein expression: in the control group, the expression of OPG protein was detected at the 8th day (1.01 +/- 0.08), and reached the expression peak (1.80 +/- 0.10), there was statistically different (P<0.05). In the different days and different concentration icariin groups, the expressions of OPG protein were all inferior to the control group. While the concentration decreasing, the expression was less. There were statistically difference (P<0.05). At the day 12, there was no significant difference of OPG protein expression between the 10(-6) mol/L icariin group and the 10(-8) mol/L icariin group (P>0.05). CONCLUSION: The effect of icariin promoting the proliferation of human osteoblast maybe is one of the mechanisms of improving the bone formation on human osteoblast.

Ab initio study of the geometry, stability, and aromaticity of the cyclic S2N3(+) cation isomers and their isoelectronic analogues.

A theoretical study of the geometries, energies, dissociation pathways, and aromaticity of the isomeric sulfur-nitrogen S(2)N(3)(+) rings reveals that the experimentally known 1,2-isomer is only stable kinetically. A rather high barrier inhibits its dissociation into the slightly lower energy N(2) and NSS(+) fragments via a stepwise mechanism. A second possible dissociation mode, into NNS and NS(+) via a concerted [3 + 2] mechanism, is endothermic. Instead, the reverse cycloaddition reaction has a low barrier and offers an exothermic route for the formation of cyclic 1,2-S(2)N(3)(+). Despite being thermodynamically more stable, the 1,3-isomer has only fleeting existence: its facile exothermic [3 + 2] cycloreversion into N(2) and SNS(+) fragments precludes observation. Nucleus independent chemical shifts (NICS) analysis reveals considerable six pi electron aromaticity for both cyclic S(2)N(3)(+) isomers, as well as their five membered ring valence isoelectronic analogues, N(5)(-), SN(4), and S(3)N(2)(2+). The decomposition routes and the energetics of these analogues also provide comparisons along the series.

[Influence of Migu capsule and strengthening spleen prescription on the expression of small intestine VDR mRNA in calf muscle on ovariectomized rats].

OBJECTIVE: To observe the effect of Migu capsule and Strengthening Spleen prescriptions on the expression of vitamin D receptor on small intestine and calf muscle of the rat, while observing whether the Chinese medicine complex prescriptions of different effect such as invigorating the kidney and strengthening the spleen had selectivity to expression of the VDR mRNA. METHODS: Copy the model of osteoporosis by ovariectomy operation, the rats were randomly divided into four groups, pseudo-resection group, model group, Migu capsule group and strengthening Spleen prescriptions group. Drug delivery 12 weeks later from operation, stomach lavage last for 12 weeks. Then, to observe the effect of medicine on the rats' bone mineral density, uterus weight, calf muscle/weight, and the VDR mRNA in small intestine and calf muscle through RT-PCR. RESULTS: Migu capsule enhanced bone mineral density (P<0.05), raised calf muscle/weight (P<0.05), up-regulated expression of calf muscle VDR mRNA in the small intestine (P<0.01). Strengthening Spleen prescriptions remained bone mineral density (P>0.05), up-regulated expression of calf muscle VDR mRNA (P<0.01), there was no obvious difference in uterus weight in Migu capsule group and Strengthening Spleen prescription group. CONCLUSION: Migu capsule and Strengthening Spleen prescriptions can cure osteoporosis by improving the expression of calf muscle VDR mRNA in the small intestine.