Study on the isolation of active constituents in Lonicera japonica and the mechanism of their anti-upper respiratory tract infection action in children

Background: Lonicera japonica has been studied extensively by scholars at home and abroad, a number of compounds have been isolated from it, which mainly include organic acids and flavonoids. Pharmacological studies have shown that Lonicera japonica has antibacterial and gall bladder-protective effects.Objective: To study the active constituents in Lonicera japonica and the mechanism of their anti-upper respiratory tract infection action in children.Methods: Compounds were identified by chromatographic methods, and the mechanism of anti-pediatric upper respiratory tract infection action of Lonicera japonica decoction was studied using experimental animals.Results: A total of four compounds were isolated, after injection of egg white, toe edema in rats in the control group was very obvious, different test concentrations of Lonicera japonica decoction all inhibited toe edema in rats to some extents, the edema was the mildest in the Lonicera japonica decoction high-dose group, which had the strongest inhibitory effect on the development of inflammation, the Lonicera japonica decoction showed certain dose-effect relationship with toe edema in rats. In the rat body temperature control experiment, while body temperature of rats in the blank group had already risen, other groups were still able to lower the body temperature of rats under the action of test drugs. The severity of ear edema in mice in the blank control group was obvious, with increased thickness which showed significant difference between left and right ears. Under test doses, three Lonicera japonica decoction groups all inhibited xylene-induced ear edema in mice.Conclusion: Lonicera japonica has an anti-upper respiratory tract infection action in children.Keywords: Lonicera japonica, chlorogenic acid butyl ester, oleanolic acid, mouse ear edem

Study on the isolation of active constituents in Lonicera japonica and the mechanism of their anti-upper respiratory tract infection action in children

Background: Lonicera japonica has been studied extensively by scholars at home and abroad, a number of compounds have been isolated from it, which mainly include organic acids and flavonoids. Pharmacological studies have shown that Lonicera japonica has antibacterial and gall bladder-protective effects. Objective: To study the active constituents in Lonicera japonica and the mechanism of their anti-upper respiratory tract infection action in children. Methods: Compounds were identified by chromatographic methods, and the mechanism of anti-pediatric upper respiratory tract infection action of Lonicera japonica decoction was studied using experimental animals. Results: A total of four compounds were isolated, after injection of egg white, toe edema in rats in the control group was very obvious, different test concentrations of Lonicera japonica decoction all inhibited toe edema in rats to some extents, the edema was the mildest in the Lonicera japonica decoction high-dose group, which had the strongest inhibitory effect on the development of inflammation, the Lonicera japonica decoction showed certain dose-effect relationship with toe edema in rats. In the rat body temperature control experiment, while body temperature of rats in the blank group had already risen, other groups were still able to lower the body temperature of rats under the action of test drugs. The severity of ear edema in mice in the blank control group was obvious, with increased thickness which showed significant difference between left and right ears. Under test doses, three Lonicera japonica decoction groups all inhibited xylene-induced ear edema in mice. Conclusion: Lonicera japonica has an anti-upper respiratory tract infection action in children

Interfacial Properties of Monolayer and Bilayer MoS2 Contacts with Metals: Beyond the Energy Band Calculations

Although many prototype devices based on two-dimensional (2D) MoS2 have been fabricated and wafer scale growth of 2D MoS2 has been realized, the fundamental nature of 2D MoS2-metal contacts has not been well understood yet. We provide a comprehensive ab initio study of the interfacial properties of a series of monolayer (ML) and bilayer (BL) MoS2-metal contacts (metal = Sc, Ti, Ag, Pt, Ni, and Au). A comparison between the calculated and observed Schottky barrier heights (SBHs) suggests that many-electron effects are strongly suppressed in channel 2D MoS2 due to a charge transfer. The extensively adopted energy band calculation scheme fails to reproduce the observed SBHs in 2D MoS2-Sc interface. By contrast, an ab initio quantum transport device simulation better reproduces the observed SBH in the two types of contacts and highlights the importance of a higher level theoretical approach beyond the energy band calculation in the interface study. BL MoS2-metal contacts have a reduced SBH than ML MoS2-metal contacts due to the interlayer coupling and thus have a higher electron injection efficiency.Comment: 36 pages, 13 figures, 3 table

Extended preclinical investigation of lactate for neuroprotection after ischemic stroke

Lactate has been shown to have beneficial effect both in experimental ischemia–reperfusion models and in human acute brain injury patients. To further investigate lactate’s neuroprotective action in experimental in vivo ischemic stroke models prior to its use in clinics, we tested (1) the outcome of lactate administration on permanent ischemia and (2) its compatibility with the only currently approved drug for the treatment of acute ischemic stroke, recombinant tissue plasminogen activator (rtPA), after ischemia–reperfusion. We intravenously injected mice with 1 µmol/g sodium l -lactate 1 h or 3 h after permanent middle cerebral artery occlusion (MCAO) and looked at its effect 24 h later. We show a beneficial effect of lactate when administered 1 h after ischemia onset, reducing the lesion size and improving neurological outcome. The weaker effect observed at 3 h could be due to differences in the metabolic profiles related to damage progression. Next, we administered 0.9 mg/kg of intravenous (iv) rtPA, followed by intracerebroventricular injection of 2 µL of 100 mmol/L sodium l -lactate to treat mice subjected to 35-min transient MCAO and compared the outcome (lesion size and behavior) of the combined treatment with that of single treatments. The administration of lactate after rtPA has positive influence on the functional outcome and attenuates the deleterious effects of rtPA, although not as strongly as lactate administered alone. The present work gives a lead for patient selection in future clinical studies of treatment with inexpensive and commonly available lactate in acute ischemic stroke, namely patients not treated with rtPA but mechanical thrombectomy alone or patients without recanalization therapy

In Vivo 1H MRS at 14.1T for the Accurate Characterization of the Lipid Profile of the Mouse Liver

1H MRS was employed at 14.1T to non-invasively quantify the lipid content of small samples (8-15 µl). In the mouse liver, good spectral stability was achieved by running individual scans within one breathing cycle. Ultra short TE STEAM with water suppression was used to estimate the unsaturation profile of the fatty acyl chains. This method was in good agreement with in vitro measurements in phantoms. High field is advantageous to accurately characterize the lipid profile of small samples such as the volumes selected in the liver of mice, with no need to increase the acquisition time for sensitivity gain

Technical and experimental features of Magnetic Resonance Spectroscopy of brain glycogen metabolism

In the brain, glycogen is a source of glucose not only in emergency situations but also during normal brain activity. Altered brain glycogen metabolism is associated with energetic dysregulation in pathological conditions, such as diabetes or epilepsy. Both in humans and animals, brain glycogen levels have been assessed non-invasively by Carbon-13 Magnetic Resonance Spectroscopy (13C-MRS) in vivo. With this approach, glycogen synthesis and degradation may be followed in real time, thereby providing valuable insights into brain glycogen dynamics. However, compared to the liver and muscle, where glycogen is abundant, the sensitivity for detection of brain glycogen by 13C-MRS is inherently low. In this review we focus on strategies used to optimize the sensitivity for 13C-MRS detection of glycogen. Namely, we explore several technical perspectives, such as magnetic field strength, field homogeneity, coil design, decoupling, and localization methods. Furthermore, we also address basic principles underlying the use of 13C-labeled precursors to enhance the detectable glycogen signal, emphasizing specific experimental aspects relevant for obtaining kinetic information on brain glycogen

Evolution of the Hepatic Lipid Profile of the Adult Mouse - in Vivo and in Vitro 1H MRS Assessments at 14.1T

The hepatic lipid content and composition were assessed in healthy mice throughout adulthood. It was found that aging and obesity contributed to increase the amount of lipids in the liver while decreasing the poly-unsaturation degree. The combination of in vivo 1H MRS assessments with in vitromeasurements on tissues extracts illustrated the important contribution of membrane lipids to the total poly-unsaturation degree of the fatty acyl chains. Changes of the unsaturation profile of cytosolic lipids can be monitored by in vivo 1H MRS, which is of interest for the study of genetic and diet-induced mice models of metabolic diseases

Effect of deep pentobarbital anesthesia on neurotransmitter metabolism in vivo: on the correlation of total glucose consumption with glutamatergic action

The effect of deep barbiturate anesthesia on brain glucose transport, TCA cycle flux, and aspartate, glutamate, and glutamine metabolism was assessed in the rat brain using 13C nuclear magnetic resonance spectroscopy at 9.4 T in conjunction with [1-13C] glucose infusions. Brain glucose concentrations were elevated, consistent with a twofold reduced cerebral metabolic rate for glucose (CMRglc) compared with light alpha-chloralose anesthesia. Using a mathematical model of neurotransmitter metabolism, several metabolic reaction rates were extracted from the rate of label incorporation. Total oxidative glucose metabolism, CMRglc(ox), was 0.33 +/- 0.03 micromol x g(-1) x min(-1). The neuronal TCA cycle rate was similar to that in the glia, 0.35 +/- 0.03 micromol x g(-1) x min(-1) and 0.26 +/- 0.06 micromol x g(-1) x min(-1), respectively, suggesting that neuronal energy metabolism was mainly affected. The rate of pyruvate carboxylation was 0.03 +/- 0.01 micromol x g(-1) x min(-1). The exchange rate between cytosolic glutamate and mitochondrial 2-oxoglutarate, Vx, was equal to the rate of neuronal pyruvate dehydrogenase flux. This indicates that Vx is coupled to CMRglc(ox), implying that the malate-aspartate shuttle is the major mechanism that facilitates label exchange across the inner mitochondrial membrane. The apparent rate of glutamatergic neurotransmission, V(NT), was 0.04 +/- 0.01 micromol x g x min, consistent with strong reductions in electrical activity. However, the rates of cerebral oxidative glucose metabolism and glutamatergic neurotransmission, CMRglc(ox)/V(NT), did not correlate with a 1:1 stoichiometry