Metal ion assistant transformation strategy to synthesize catechol-based metal-organic frameworks from Ti3C2Tx precursors.

Chemical transformation strategy is capable of fabricating nanomaterials with well-defined structures and fascinating performance via controllable crystallization kinetics in the phase transformation. V2CTx MXene has been used as precursors to fabricate vanadium porphyrin metal-organic frameworks (V-PMOFs) via the coordination of deprotonated carboxylic acid ligands. However, the rational and in-depth exploration of synthesis mechanism with the aim of enriching the variety of MXene (i.e., Ti3C2Tx) and organic ligands (i.e., catechol-based) to design new MOFs is rarely reported. Herein, we have first developed a metal ion assistant transformation strategy to synthesize three-dimensional catechol-based TiCu-HHTP (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) MOFs with a non-interpenetrating SrSi2 (srs) framework using two-dimensional Ti3C2Tx as precursors. The unique synergetic transformation mechanism involves the electron transfer from Ti3C2Tx to electrostatically adsorbed Cu2+ ion for redox reaction, the subsequent Ti-C bond rupture for Ti4+ ion release, and the continuous chelation coordination between Ti4+/Cu2+ and HHTP. Ti3C2Tx precursors and auxiliary metal ion could be rationally substituted by V2CTx and Mn+ (e.g., Ni2+, Co2+, Mn2+, and Zn2+), respectively. This strategy lays the foundation for the design and synthesis of innovative and multifarious MOFs derived from MXene or other unconventional metal precursors.

Herbal Compounds Play a Role in Neuroprotection through the Inhibition of Microglial Activation.

Since microglia possess both neuroprotective and neurotoxic potential, they play a crucial role in the central nervous system (CNS). Excessive microglial activation induces inflammation-mediated neuronal damage and degeneration. At present, numerous herbal compounds are able to suppress neurotoxicity via inhibiting microglial activation. Therefore, many researchers focus on pharmacological inhibitors of microglial activation to ameliorate neurodegenerative disorders. Further work should concentrate on the exploration of new herbal compounds, which characteristically inhibit microglial neurotoxicity, rather than modulating neuroprotection alone. In this review, we summarize these herbal compounds, which in the past several years have been shown to exert potential neuroprotective activity by inhibiting microglial activation. The therapeutic targets and pharmacological mechanisms of these compounds have also been discussed.

trans-Cinnamaldehyde Inhibits Microglial Activation and Improves Neuronal Survival against Neuroinflammation in BV2 Microglial Cells with Lipopolysaccharide Stimulation.

BACKGROUND: Microglial activation contributes to neuroinflammation and neuronal damage in neurodegenerative disorders including Alzheimer's and Parkinson's diseases. It has been suggested that neurodegenerative disorders may be improved if neuroinflammation can be controlled. trans-cinnamaldehyde (TCA) isolated from the stem bark of Cinnamomum cassia possesses potent anti-inflammatory capability; we thus tested whether TCA presents neuroprotective effects on improving neuronal survival by inhibiting neuroinflammatory responses in BV2 microglial cells. RESULTS: To determine the molecular mechanism behind TCA-mediated neuroprotective effects, we assessed the effects of TCA on lipopolysaccharide- (LPS-) induced proinflammatory responses in BV2 microglial cells. While LPS potently induced the production and expression upregulation of proinflammatory mediators, including NO, iNOS, COX-2, IL-1ß, and TNF-α, TCA pretreatment significantly inhibited LPS-induced production of NO and expression of iNOS, COX-2, and IL-1ß and recovered the morphological changes in BV2 cells. TCA markedly attenuated microglial activation and neuroinflammation by blocking nuclear factor kappa B (NF-κB) signaling pathway. With the aid of microglia and neuron coculture system, we showed that TCA greatly reduced LPS-elicited neuronal death and exerted neuroprotective effects. CONCLUSIONS: Our results suggest that TCA, a natural product, has the potential of being used as a therapeutic agent against neuroinflammation for ameliorating neurodegenerative disorders.

Effects of Yoga on Heart Rate Variability and Depressive Symptoms in Women: A Randomized Controlled Trial.

OBJECTIVES: The purpose of the study was to investigate the effects of a 12-week yoga program on heart rate variability (HRV) and depressive symptoms in depressed women. METHODS: This was a randomized controlled trial. Twenty-six sedentary women scoring ≥14 on the Beck Depression Inventory-II were randomized to either the yoga or the control group. The yoga group completed a 12-week yoga program, which took place twice a week for 60 min per session and consisted of breathing exercises, yoga pose practice, and supine meditation/relaxation. The control group was instructed not to engage in any yoga practice and to maintain their usual level of physical activity during the course of the study. Participants' HRV, depressive symptoms, and perceived stress were assessed at baseline and post-test. RESULTS: The yoga group had a significant increase in high-frequency HRV and decreases in low-frequency HRV and low frequency/high frequency ratio after the intervention. The yoga group also reported significantly reduced depressive symptoms and perceived stress. No change was found in the control group. CONCLUSIONS: A 12-week yoga program was effective in increasing parasympathetic tone and reducing depressive symptoms and perceived stress in women with elevated depressive symptoms. Regular yoga practice may be recommended for women to cope with their depressive symptoms and stress and to improve their HRV.

Trans-cinnamaldehyde improves memory impairment by blocking microglial activation through the destabilization of iNOS mRNA in mice challenged with lipopolysaccharide.

Microglia activation and neuroinflammation are critically involved in pathogenesis of neurodegenerative disorders. Patients with neurodegenerative disorders often suffer memory impairment and currently there is no effective treatment for inflammation-led memory impairment. Trans-cinnamaldehyde (TCA) isolated from medicinal herb Cinnamomum cassia has been shown to exhibit anti-inflammatory capability. However, the potential of TCA to be used to improve memory impairment under neuroinflammation has not been explored. Primary microglia stimulated by lipopolysaccharide (LPS) were used to evaluate the potential anti-neuroinflammatory effects of TCA by examining the production of nitric oxide (NO), expression of inducible nitric oxide synthase (iNOS), pro-inflammatory cytokines, and activation of MAPKs. A mouse model of LPS-induced memory impairment was established to assess the neuroprotective effects of TCA against memory deficit and synaptic plasticity inhibition by both behavioral tests and electrophysiological recordings. TCA pretreatment decreased LPS-induced morphological changes, NO production and IL-1ß release in primary microglia. Decreased NO production was due to the accelerated degradation of iNOS mRNA in LPS-stimulated microglia through TCA's inhibitory effect on MEK1/2-ERK1/2 signaling pathway. TCA was able to reduce the levels of iNOS and phosphorylated ERK1/2 in hippocampus of mice challenged with LPS. Most importantly, TCA significantly lessened memory deficit and improved synaptic plasticity in LPS-challenged mice. This study demonstrates that TCA suppressed microglial activation by destabilizing iNOS mRNA, which leads to improved memory impairment in mice suffering neuroinflammation.

[Effect of yizhi jiannao granule on the behavior and neuron apoptosis in SAMP/8 mice].

OBJECTIVE: To investigate the effect of yizhi jiannao granule concentration fluid (YCF) on the behavior, the apoptosis rate of hippocampus neuron and the expression of apoptosis gene Bcl-2, Bax in senescence accelerated mice Senile-Prone/8 (SAMP/8), and to discuss some mechanism of traditional chinese medicine YCF in improving the capability of learning and memory. METHODS: Forty 6-month old SAMP/8 mice were randomly divided into the old group, huperzine A (Hup-A) group and YCF group. Ten 4-month old SAMP/8 mice were served as a young control group. Four groups were given different drugs for 8 weeks, their behavior changes were observed, and the hippocampus were taken out to examine the apotosis rate by flow cytomeutry (FCM) and the expression of Bcl-2, Bax mRNA by RT-PCR. RESULTS: In the YCF group, the escape latency was significantly shortened, the time of swim in the platform quadrant significantly increased, the apoptosis rate of hippocampus neural decreased; the level of Bcl-2 mRNA and the rate of Bcl-2/Bax increased, and the level of Bax mRNA decreased. CONCLUSION: Yizhi jiannao granule can decrease the neuron apoptosis rate and the Bax level, increase the Bcl-2 level, and modulate the rate of Bcl-2/Bax in SAMP/8 brain, which is probably part of the mechanisms of inhibiting the apoptosis and improving learning and memory.

UV-vis spectroscopic study directly detecting inorganic phosphorus in urine and our reagent kit.

The determination of inorganic phosphorus in human urine is very important, since it has diagnostic value in some clinical cases. Here we apply a simple, sensitive and direct method to determine inorganic phosphorus in urine. This new ensemble is prepared by adding ytterbium chloride and pyrocatechol violet in a 2:1 molar ratio in an aqueous solution of 10 mM 2-[4-(2-hydroxyethyl)-1-piperazinyl]ethanesulfonic acid buffer at pH 7.0. The addition of the urine sample turned the blue ensemble yellow and altered the UV-vis absorption spectra. The ensemble exhibits excellent selectivity for inorganic phosphorus over other constituents of urine. We validate the accuracy of our method by the standard procedure (molybdenum blue assay for phosphate). The detection results are basically consistent with normal excretion of phosphate. Furthermore, we fabricated a new kind of inorganic phosphorus reagent kit, which enables us to inspect phosphate concentrations of urine with the naked eye. Fit for all kinds of various clinic uses, our reagent kit is a hopeful substitute for the molybdenum reagent kit.

Repellent effect of plant essential oils against Aedes albopictus.

Six essential oils: asteraceae oil, rutaceae oil, mentha piperta oil, carvacryl oil, citronella oil, and eucalyptus oil were tested for evaluation of their repellent effects against Aedes albopictus mosquitoes under laboratory conditions. Only citronella oil and eucalyptus oil were tested with human beings. There was considerable protection for mice. Carvacryl oil (7%) provided 100% protection for mice after 7 h. Eucalyptus oil (15%) gave protection to humans for least 3 h; the protection time was prolonged to 5 h after adding 5% vanillin. The mixture could be developed into a practical product after the field evaluation.

[Study on the spectral properties of caffeic acid and its derivatives].

Caffeic acid, chlorogenic acid and forsythiaside are active components of Chinese herbs and have diverse biological activities. As the similar compounds, they all include 3, 4-dihydroxy-phenyl in their structures. In this paper, the fluorescence and UV spectra of the caffeic acid, chlorogenic acid and forsythiaside were studied in different pH. The spectra properties of fluorescence and UV were further discussed in view of the phenol hydroxyl states, free, dissociative and protonated. It is found that the luminescence intensity, the peak shape and peak wavelength change with pH. Experimental results also indicate that caffeic acid, chlorogenic acid and forsythiaside can emit fluorescence in wide range of pH (2-12), and fluorescent intensity is enhanced as the dissociation of 4-phenol hydroxyl. On the other hand, fluorescent intensity may be quenched as the dissociation of 3-phenol hydroxyl. Furthermore, in strong acidic or in strong basic media, the fluorescence is quenched partly, and the shape of UV spectra changed greatly in strong basic media, meaning that their molecular structures are changed considerable.