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As important secondary plant metabolites, naphthoquinones exhibit a wide range of biological activities. However, their potential as sustainable alternatives to synthetic acaricides has not been studied. This study for the first time investigates the acaricidal activity of naphthoquinones against Psoroptes cuniculi in vitro. Furthermore, the in vivo activity, the skin irritation effects, the cytotoxicity and the inhibitory activities against mite acetylcholinesterase (AChE) and glutathione S-transferase (GST) of the two compounds that displayed the best insecticidal activity in vitro were evaluated. Among fourteen naphthoquinones and their analogs, juglone and plumbagin were observed to possess the strongest acaricidal activities against P. cuniculi with LC50 values of 20.53 ppm and 17.96 ppm, respectively, at 24 h. After three treatments, these two chemicals completely cured naturally infested rabbits in vivo within 15 days, and no skin irritation was found in any of the treated rabbits. Compared to plumbagin, juglone presented no or weak cytotoxicity against HL-7702 cells. Moreover, these two chemicals significantly inhibited AChE and GST activity. These results indicate that juglone has promising toxicity against P. cuniculi, is safe for both humans and animals at certain doses, and could be used as a potential alternative bio-acaricide for controlling the development of psoroptic mange in agricultural applications.

In order to reveal the chemical substance basis of pharmacodynamic effects of Zuotai, energy dispersive spectrometry of X-ray (EDX), X-ray fluorescence spectroscopy (XRF), synchrotron radiation X-ray absorption fine structure (SR-XAFS), X-ray diffraction (XRD), scanning electron microscope (SEM) and atomic force microscope (AFM) were used to analyze the elements, the chemical valence and local structure of mercury, and the chemical phase composition and micro-morphology of Zuotai. EDX and XRF analysis shows that the main elements in Zuotai are Hg and S, with some other minor elements, such as 0, Fe, Al, Cu, K, Ag, Ca, Mg etc. SR-XAFS analysis shows that: the oxidation state of mercury in Zuotai is divalence, its neighbor atoms are S, and its coordination number is four. XRD assay found that β-HgS (cubic, F-43m 216) and S8 (orthorhombic, Fddd 70) are the main phase compositions in Zuotai. Besides, it also has a small amount of C (hexagonal, P63/mmc 194), Fel.05 S0.95 (hexagonal, P63/mmc 194), Cu6S6 (hexagonal, P63/mmc 194), Cu1.8 S (cubic, F-43m 216) and so on. And it was found that the crystallinity of Zuotai is about 59%, and the amorphous morphology substance in it is about 41%. SEM and AFM detection suggests that Zuotai is a kind of ancient micro-nano drug, and its particle size is mainly in the range of 100-600 nm, even less than 100 nm, which commonly further aggregate into several to 30 µm loose amorphous particles. In summary, the present study elucidated physicochemical characterization(elements composition, coordination information of mercury, phase composition and micro-morphology) of Zuotai, and it will play a positive role in promoting the interpretation of this mysterious drug.;

Liquid chromatography coupled with diode array detector and electrospray ionization mass spectrometry was developed for the qualitative and quantitative comparison of the main constituents in Saussurea laniceps (SL) and S. medusa (SM), two species of plants used under the name "Xuelianhua" in traditional Tibetan medicine. A method validation including linearity, limit of detection, precision and recovery was performed. The results showed that a good linearity with R<sup>2</sup> &gt; 0.99 was achieved, and the limit of detection of the quantified constituents was reported to be between 0.8 and 3.3 ng. The relative standard deviation value was below 3.82% for repeatability, and recovery studies for the quantified compounds were found to be within the range 90.92-103.12%. The unique properties of the present method were evaluated by analyzing twelve related herbal samples including five S. laniceps samples and seven S. medusa samples. Twenty-two compounds including phenolic acids, cumarins, lignanoids and flavonoids were identified by online ESI-MS and by comparison with literature data and standard compounds, and seven of them were quantified by LC-DAD simultaneously. The results demonstrated that the common constituents in the two herbs were protocatechuic acid, syringoside, chlorogenic acid, isoquercitroside, 1,5-dicaffeoylquinic acid, apigenin 7-O-Îø-d-glucoside, chrysoeriol 7-O-Îø-d-glucoside, acacetin 7-O-Îø-d-glucoside, apigenin and chrysoeriol. In the present study, it was found that the characteristic constituents were umbelliferone, scopoletin and their glucosides in S. laniceps, as well as arctiin and arctigenin in S. medusa. It was feasible to choose these characteristic compounds for the quality evaluation as well as chemical authentication of the two related herbs. The results also support discrimination between the two species when using them in folk medicine.

Because of the absence of the time course of histological nonalcoholic fatty hepatitis with subsequent fibrotic progression, the effective approaches available for controlling the onset and progression of non-alcoholic steatohepatitis (NASH) remain limited. Therefore, we detected the serum and liver tissue related lipid metabolism disorder, liver pathology and relative molecular makers alteration dynamically in a high fat-sucrose diet during different time points. High fat-sucrose diet significantly increased the serum lipid level on day 10. The excess lipid accumulation in liver was referred to as simple steatosis after the feeding of a high fat-sucrose diet for 20 days. The high fat-sucrose diet induced a hepatic inflammation response on day 30. Similarly, hepatic fibrosis was also initiated on day 30 and gradually formed from the 30th to the 50th day. Oxidative stress may be related with the process from NASH to liver fibrosis. Insulin resistance was involved in the progression from hepatic steatosis to NASH with hepatic fibrosis from the 20th to the 50th day. In conclusion, we established a high fat-sucrose diet induced nonalcoholic fatty hepatitis with liver fibrosis rat model, which presented the time course of histological nonalcoholic steatohepatitis and the initiation and progression change of characteristic molecular makers in the process from steatosis to hepatic fibrosis.

The study aims at providing a new suitable way to promote artificial cultivation, solving the problem of resources increasingly endangered wild medicine, and protecting the wild resources of Tibetan medicine. The content of quercetin,kaempferol and isorhamnetin was determined by HPLC. The correlation between flavonoids components and ecological factors was analyzed using partial least-squares regression (PLSR). Based on Maxent model combining using ArcGIS software, suitable regionalization for H.rhamnoides subsp. sinensis was studied.The results showed that the difference of quercetin,kaempferol and isorhamnetin content in samples from different regions were obvious. The main factors effecting quercetin content accumulation were the altitude andthe average monthly precipitation in January and August. The main factors effecting kaempferol accumulation were the altitude andthe average monthly precipitation in the coldest quarter and December. The main factors effecting isorhamnetin accumulation were the average monthly precipitation in August, January and the coldest quarter.The regional distribution suitability index for H.rhamnoides subsp. sinensis was 0-0.708. The suitable area 590 500 km², accounting for 6.13% of the total area. The preferably suitable area was 552 500 km², accounting for 5.73% of the total area.The methods used in the study is simple and feasible, the result is reliable which provide a new approach for Tibetan medicine resources sustainable exploitation and utilization.

A simple, efficient and accurate liquid chromatographic method was established to determine five flavonoid aglycones, 7-hydroxy flavonone, pinocembrin, 2′,4′-dihydroxy chalcone, 2′-hydroxy-4′-methoxy chalcone and pinostrobin in the whole plant powder of <i>Oxytropis falcata</i> Bunge. These five compounds were separated on an Agilent Zorbax Eclipse XDB-C<sub>8</sub> column (150 × 4.6 mm, 5 μm). Mobile phases were composed of water containing 0.1% <i>v/v</i> formic acid and acetonitrile using gradient elution. The established method was validated for linearity, accuracy, precision, limit of detection and quantitation, repeatability and stability.

Dermatosis often as a chronic disease requires effective long-term treatment; a comprehensive evaluation of mental health of dermatology drug does not receive enough attention. An interaction between dermatology and psychiatry has been increasingly described. Substantial evidence has accumulated that psychological stress can be associated with pigmentation, endocrine and immune systems in skin to create the optimal responses against pathogens and other physicochemical stressors to maintain or restore internal homeostasis. Additionally, given the common ectodermal origin shared by the brain and skin, we are interested in assessing how disruption of skin systems (pigmentary, endocrine and immune systems) may play a key role in brain functions. Thus, we selected three drugs (hydroquinone, isotretinoin, tacrolimus) with percutaneous excessive delivery to respectively intervene in these systems and then evaluate the potential neurotoxic effects. Firstly, C57BL/6 mice were administrated a dermal dose of hydroquinone cream, isotretinoin gel or tacrolimus ointment (2%, 0.05%, 0.1%, respectively, 5 times of the clinical dose). Behavioral testing was performed and levels of proteins were measured in the hippocampus. It was found that mice treated with isotretinoin or tacrolimus, presented a lower activity in open-field test and obvious depressive-like behavior in tail suspension test. Besides, they damaged cytoarchitecture, reduced the level of 5-HT-5-HT1A/1B system and increased the expression of apoptosis-related proteins in the hippocampus. To enable sensitive monitoring the dose-response characteristics of the consecutive neurobehavioral disorders, mice received gradient concentrations of hydroquinone (2%, 4%, 6%). Subsequently, hydroquinone induced behavioral disorders and hippocampal dysfunction in a dose-dependent response. When doses were high as 6% which was 3 times higher than 2% dose, then 100% of mice exhibited depressive-like behavior. Certainly, 6% hydroquinone exposure elicited the most serious impairment of hippocampal structure and survival. The fact that higher doses of hydroquinone are associated with a greater risk of depression is further indication that hydroquinone is responsible for the development of depression. These above data demonstrated that chronic administration of different dermatology drugs contributed into common mental distress. This surprising discovery of chemical stressors stimulating the hippocampal dysfunction, paves the way for exciting areas of study on the cross-talk between the skin and the brain, as well as is suggesting how to develop effective and safe usage of dermatological drugs in daily practice.

Stress, specifically chronic unpredictable stress and chronic restrained stress, induce depigmentation in C57BL/6 mice. Fluoxetine promoted melanin production and the migration of melanocytes via 5-HT1A receptor and 5-HT2A receptor, respectively.<br><br>Display Omitted<br>• Fluoxetine ameliorates CUMS and CRS induced depigmentation in C57BL/6 mouse. • Fluoxetine induces melanogenesis via activating the phosphorylation of p38 MAPK signaling pathways. • 5-HT1A and 2A receptors regulated fluoxetine increased melanocyte melanogenesis and migration.<br>Background: 5-HT1A receptor was participated in fluoxetine induced melanogenesis in melanocytes and in normal C57BL/6 mice, but we know little about whether other 5-HT receptors are involved in regulation of fluoxetine promotes pigmentation.<br>Objective: To investigate the role of 5-HT receptors in regulation of fluoxetine ameliorates chronic unpredictable mild stress (CUMS) and chronic restraint stress (CRS) induce hypopigmentation in C57BL/6 mice.<br>Methods: CUMS and CRS were used to induce depigmentation in mice and evaluate the effect of fluoxetine. Western blot, immunohistochemistry and Q-PCR assay were used to determine the levels of protein and mRNA. Masson Fontana staining was used for melanin staining and FITC-Phalloidin staining was used to detect the expression of F-actin. Zebrafish and B16F10 cells were used for the mechanism research.<br>Results: Fluoxetine (2.6 mg/kg, ig) ameliorated hypopigmentation induced by CUMS and CRS in mice, significantly increased the mRNA and protein levels of 5-HT1 A and 5-HT2 A receptors in mice and B16F10 cells. The effect of fluoxetine on melanogenesis in B16F10 cells and zebrafish were inhibited by WAY100635 (a selective 5-HT1 A receptor antagonist) and ketanserin (a 5-HT2 A receptor antagonist), respectively. Activation of p38 MAPK signaling pathways was contributed to fluoxetine induced melanogenesis and inhibited by WAY100635, but not ketanserin. However, ketanserin selectively weakened the action of fluoxetine promoted migration and up-regulated Rab27a protein expression in B16F10 cells.<br>Conclusions: 5-HT1 A and 2 A receptors contribute to melanogenesis and migration property of fluoxetine. The newly revealed mechanism indicates that fluoxetine and its analogues may be a potential drug for treatment of depigmentation disorders.

This study is aimed to explore the effect of nitrogen, phosphorus and potassium combined application on the active components of Rhodiola crenulata. R. crenulata was used as the research object, "3414" fertilization experiment were conducted with regular fertilization of NPK(N 60 kg·hm⁻², P₂O₅ 100 kg·hm⁻²,KCl 160 kg·hm⁻²) to study the effect of different rates of NPK fertilization on the total amount of 4 phenolic constituents of gallic acid, salidroside, tyrol and ethyl gallate through field test. The results show that the content of salidroside was higher in the treatment of N₁P₂K₁ and N₁P₂K₂, andthe total amount of four phenols was higher in the treatment of N₁P₂K₂ and N₂P₂K₂. The suitable level of nitrogen, phosphorus and potassium promoted the accumulation of the 4 kinds of phenols.The amount of fertilizer recommended by the three factor fertilizer effect equation,(N 0 kg·hm⁻²,P₂O₅ 150 kg·hm⁻²,KCl 31.71 kg·hm⁻²) obtained the highest content of salidroside, and it was 1.54%.(N 35.54 kg·hm⁻²,P₂O₅ 150 kg·hm⁻²,KCl 237.73 kg·hm⁻²)obtained the highest content of 4 kinds of phenolic compounds, and it was 1.93%. This study provides a reference for the standardization of artificial planting of endangered Tibetan medicine.

With the rapid development of Tibetan medicine industry, the study on plateau medicinal plants' endangered status is not enough, measures to protect is weak and the plateau ecological environment' inherent vulnerability, resulted in the shortage of Tibetan medicinal resources and affect the sustainable development . According to the existing endangered information of Tibetan medicine resources, how to formulate feasible protection plan, is an urgent problem of the rational development and utilization of Tibetan medicine resources to be solved. To find out the endangered Tibetan medicines in Qinghai Tibet Plateau, the Grade division method of Chinese Rare and Endangered Plants was applied, the endangered species were sorted out, which divided into class one (threatened) eleven species, class two (rare) twenty-one species, and class three (fading) forty-two species,a total of seventy-four species.In addition to national protection list in "Chinese rare and endangered plants". It's proposed to increase the endangered Tibetan medicinal species. Finally, according to the endangered status of the resources,from the survey of endangered Tibetan medicinal species regularly, the germplasm repository establishment of endangered Tibetan medicine, in situ conservation, artificial cultivation research and renew the idea, reasonable development and utilization, a total of 5 aspects to discussed the protection strategy, to provide a scientific basis for the protection and sustainable utilization of Tibetan medicine resources in Qinghai-Tibet Plateau.

To achieve a high yield of tropane alkaloids (TA) and exploit the alpine plant sustainably, an optimized protocol for induction and establishment of hairy roots culture of <i>Prezwalskia tangutica</i> Maxim was developed through selection of appropriate <i>Agrobacterium</i> strain and the explant type. The hypocotyl is more readily facile to induce the HR than the cotyledon is when infected with the three different agrobacterium strains. MUS440 has an efficiency (of up to 20%), whereas the ATCC10060 (A4) can induce HR on both types of explants with the highest frequency (33.33%), root length (21.17 ± 2.84 cm), and root number (10.83 ± 1.43) per explant than the other strains. The highest HR production resulted from using hypocotyl as explants. Independent transformed HR was able to grow vigorously and to propagate on a no-hormone 1/2MS liquid medium. The presence of pRi <i>rol</i>B gene in transformation of HR was confirmed by PCR amplification. In the liquid medium, the HR growth curve appeared to be “S” shaped, and ADB had increased to 4.633 g/l. Moreover, HPLC analysis showed that HR lines have an extraordinary ability to produce atropine (229.88 mg/100 g), anisodine (4.09 mg/100 g), anisodamine (12.85 mg/100 g), and scopolamine (10.69 mg/100 g), which were all more significant than the control roots. In conclusion, our study optimized the culture condition and established a feasible genetics reactor for <i>P. tangutica</i> green exploration and biological study in the alpine region.

The preparation of biocatalysts based on immobilized trypsin is of great importance for both proteomic research and industrial applications. Here, we have developed a facile method to immobilize trypsin on hydrophobic cellulose-coated silica nanoparticles by surface adsorption. The immobilization conditions for the trypsin enzyme were optimized. The as-prepared biocatalyst was characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, and elemental analysis. In comparison with free enzyme, the immobilized trypsin exhibited greater resistances against thermal inactivation and denaturants. In addition, the immobilized trypsin showed good durability for multiple recycling. The general applicability of the immobilized trypsin for proteomic studies was confirmed by enzymatic digestion of two widely used protein substrates: bovine serum albumin (BSA) and cytochrome c. The surface adsorption protocols for trypsin immobilization may provide a promising strategy for enzyme immobilization in general, with great potential for a range of applications in proteomic studies.

Stress has been demonstrated to play an important role in hair follicle function and the pathogenesis of some hair disorders. The central hypothalamic-pituitary-adrenal (HPA) axis is activated by stress stimuli, synthesizes and releases various components and eventually induces the pathogenesis and recurrence of peripheral diseases. Our aim is to compare the different responses under exposure of stress in hair follicle function among different mouse strains, and to detect the involvement of the central HPA axis after stress in hair follicle growth and melanogenesis. In this study, we exposed different mouse strains (C57BL/6, CBA/J, C3H/HeN, BALB/c and ICR) to a 21-day chronic restraint stress protocol and selected C57BL/6, CBA/J and BALB/c mice for further study because of their significant behavioral alterations. Then, we evaluated and compared the different responses and sensitivity to chronic restraint stress in hair follicle function and central HPA axis among the selected strains. The results showed that expression of POMC, CRF and GR mRNA and protein and serum levels of corticosterone were inhibited in response to stress. These findings suggested that chronic restraint stress may inhibit hair follicle growth and melanogenesis via regulating the key elements of the central HPA axis. In addition, the results revealed different mouse strains exhibit different responses in the central HPA axis and hair follicle after stress exposure. C57BL/6 might be the most sensitive strain among the three strains tested as well as an appropriate strain to study possible pathophysiological mechanisms by which the nervous system influences skin function and screen dermatological drugs suitable for psychotherapy. We believe the current study will provide some useful information for researchers who are interested in the bidirectional communication between the nervous and skin systems and the management of stress-induced cutaneous diseases. [ABSTRACT FROM AUTHOR]

Stress has been demonstrated to play an important role in hair follicle function and the pathogenesis of some hair disorders. The central hypothalamic-pituitary-adrenal (HPA) axis is activated by stress stimuli, synthesizes and releases various components and eventually induces the pathogenesis and recurrence of peripheral diseases. Our aim is to compare the different responses under exposure of stress in hair follicle function among different mouse strains, and to detect the involvement of the central HPA axis after stress in hair follicle growth and melanogenesis. In this study, we exposed different mouse strains (C57BL/6, CBA/J, C3H/HeN, BALB/c and ICR) to a 21-day chronic restraint stress protocol and selected C57BL/6, CBA/J and BALB/c mice for further study because of their significant behavioral alterations. Then, we evaluated and compared the different responses and sensitivity to chronic restraint stress in hair follicle function and central HPA axis among the selected strains. The results showed that expression of POMC, CRF and GR mRNA and protein and serum levels of corticosterone were inhibited in response to stress. These findings suggested that chronic restraint stress may inhibit hair follicle growth and melanogenesis via regulating the key elements of the central HPA axis. In addition, the results revealed different mouse strains exhibit different responses in the central HPA axis and hair follicle after stress exposure. C57BL/6 might be the most sensitive strain among the three strains tested as well as an appropriate strain to study possible pathophysiological mechanisms by which the nervous system influences skin function and screen dermatological drugs suitable for psychotherapy. We believe the current study will provide some useful information for researchers who are interested in the bidirectional communication between the nervous and skin systems and the management of stress-induced cutaneous diseases.

As metabolomics is widely used in the study of disease mechanisms, an increasing number of studies have found that metabolites play an important role in the occurrence of diseases. The aim of this study is to investigate the effects and mechanisms of quercetin in high-fat-sucrose diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) development using nontargeted metabolomics. A rat model of NAFLD was established by feeding with an HFD for 30 and 50 days. The results indicated quercetin exhibited hepatoprotective activity in 30-day HFD-induced NAFLD rats by regulating fatty acid related metabolites (adrenic acid, etc.), inflammation-related metabolites (arachidonic acid, etc.), oxidative stress-related metabolites (2-hydroxybutyric acid) and other differential metabolites (citric acid, etc.). However, quercetin did not improve NAFLD in the 50-day HFD; perhaps quercetin was unable to reverse the inflammation induced by a long-term high-fat diet. These data indicate that dietary quercetin may be beneficial to NAFLD in early stages. Furthermore, combining metabolomics and experimental approaches opens avenues to study the effects and mechanisms of drugs for complex diseases.

As metabolomics is widely used in the study of disease mechanisms, an increasing number of studies have found that metabolites play an important role in the occurrence of diseases. The aim of this study is to investigate the effects and mechanisms of quercetin in high-fat-sucrose diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) development using nontargeted metabolomics. A rat model of NAFLD was established by feeding with an HFD for 30 and 50 days. The results indicated quercetin exhibited hepatoprotective activity in 30-day HFD-induced NAFLD rats by regulating fatty acid related metabolites (adrenic acid, etc.), inflammation-related metabolites (arachidonic acid, etc.), oxidative stress-related metabolites (2-hydroxybutyric acid) and other differential metabolites (citric acid, etc.). However, quercetin did not improve NAFLD in the 50-day HFD; perhaps quercetin was unable to reverse the inflammation induced by a long-term high-fat diet. These data indicate that dietary quercetin may be beneficial to NAFLD in early stages. Furthermore, combining metabolomics and experimental approaches opens avenues to study the effects and mechanisms of drugs for complex diseases.

Substance P (SP) is a candidate mediator along the brain-skin axis and can mimic the effects of stress to regulate melanogenesis. Previously, we and others have found that the regulation of SP for pigmentary function was mediated by neurokinin 1 receptor (NK1R). Emerging evidence has accumulated that psychologic stress can induce dysfunction in the cutaneous serotonin 5-hydroxytryptamine (5-HT)-5-HT1A/1B receptor system, thereby resulting in skin hypopigmentation. Moreover, NK1R and 5-HTR (except 5-HT3) belong to GPCR. The present study aimed at assessing the possible existence of NK1R-5-HTR interactions and related melanogenic functions. Western blot and PCR detection revealed that SP reduced expression of 5-HT1A receptor via the NK1 receptor. Biochemical analyses showed that NK1R and 5-HT1AR could colocalize and interact in a cell and in the skin. When the N terminus of the NK1R protein was removed NK1R surface targeting was prevented, the interaction between NK1R-5-HT1AR decreased, and the depigmentation caused by SP and WAY100635 could be rescued. Importantly, pharmaceutical coadministration of NK1R agonist (SP) and 5-HT1A antagonist (WAY100635) enhanced the NK1-5-HT1A receptor coimmunoprecipitation along with the depigmentary response. SP and WAY100635 cooperation elicited activation of a signaling cascade (the extracellular, regulated protein kinase p-JNK signaling pathway) and inhibition of p70S6K1 phosphorylation and greatly reduced melanin production in vitro and in vivo in mice and zebrafish. Moreover, the SP-induced depigmentation response did not be occur in 5-htr1aa+/- zebrafish embryos. Taken together, the results of our systemic study increases our knowledge of the roles of NK1R and 5-HT1AR in melanogenesis and provides possible, novel therapeutic strategies for treatment of skin hypo/hyperpigmentation.-Wu, H., Zhao, Y., Huang, Q., Cai, M., Pan, Q., Fu, M., An, X., Xia, Z., Liu, M., Jin, Y., He, L., Shang, J. NK1R/5-HT1AR interaction is related to the regulation of melanogenesis.

2′,4′-Dihydroxychalcone (TFC), one of the main components in Herba Oxytropis, belongs to the flavonoid group, which is known to have anti-tumor activity in vitro. In this study, the authors examined the effects of TFC on cell proliferation and apoptosis in human gastric cancer MGC-803 cells. The MTT assay results showed that TFC was able to induce cytotoxicity in MGC-803 cells in a concentration- and time-dependent manner. Acridine orange/ethidium bromide (AO/EB) staining analysis indicated that the cytotoxicity induced by TFC was mediated by apoptosis, and flow cytometry analysis indicated an increase in apoptotic cells after treatment with TFC. Furthermore, typical apoptotic morphology such as condensed chromatin, irregular nuclei, vacuoles, and dispersed granular material in the nuclear compartment were also observed using a transmission electron microscope. These results suggested that TFC can inhibit the growth of MGC-803 cells and induce apoptosis. However, further studies are necessary to investigate the possible mechanism.

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