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Sleep deprivation has been shown to exacerbate pain sensitivity and may contribute to the onset of chronic pain, yet the precise neural mechanisms underlying this association remain elusive. In our study, we explored the contribution of cholinergic neurons within the medial habenula (MHb) to hyperalgesia induced by sleep deprivation in rats. Our findings indicate that the activity of MHb cholinergic neurons diminishes during sleep deprivation and that chemogenetic stimulation of these neurons can mitigate the results. Interestingly, we did not find a direct response of MHb cholinergic neurons to pain stimulation. Further investigation identified the interpeduncular nucleus (IPN) and the paraventricular nucleus of the thalamus (PVT) as key players in the pro-nociceptive effect of sleep deprivation. Stimulating the pathways connecting the MHb to the IPN and PVT alleviated the hyperalgesia. These results underscore the important role of MHb cholinergic neurons in modulating pain sensitivity linked to sleep deprivation, highlighting potential neural targets for mitigating sleep deprivation-induced hyperalgesia.
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In this study, the effect of hydrothermal treatment with different temperatures (120-180⯰C) on the rheological properties of xanthan gum was evaluated. When the temperature of hydrothermal treatment was relatively low (120⯰C), the rheological properties of the hydrothermally treated xanthan gum was similar to the untreated xanthan gum (pseudoplastic and solid-like/gel-like behavior). However, as the temperature of hydrothermal treatment was higher, the rheological properties of the hydrothermally treated xanthan gum changed greatly (e.g., a wider range of Newtonian plateaus in flow curves, existence of a critical frequency between the storage modulus (G') and the loss modulus (G") in the dynamic viscoelasticity measurement, variation of complex viscosity). Although the hydrothermal treatment showed little influence on the functional groups of xanthan gum, it altered the micromorphology of xanthan gum from uneven and rough lump-like to thinner and smoother flake-like. In addition, higher concentration (2â¯%) of hydrothermally treated xanthan gum made its viscosity close to that of the untreated xanthan gum (1â¯%). Besides, hydrothermal treatment also affected the effect of temperature and salt (CaCl2) adding on the rheological properties of xanthan gum. Overall, this study can provide some useful information on the rheological properties of xanthan gum after hydrothermal treatment.
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Polissacarídeos Bacterianos , Reologia , Temperatura , Polissacarídeos Bacterianos/química , Viscosidade , Água/químicaRESUMO
Prevotella intermedia, a Gram-negative bacterium from the Bacteroidota phylum, is associated with periodontitis. Other species within this phylum are known to possess the general O-glycosylation system. The O-glycoproteome has been characterized in several species, including Tannerella forsythia, Porphyromonas gingivalis, and Flavobacterium johnsoniae. In our study, we used electron cryotomography (cryoET) and glycoproteomics to reveal the ultrastructure of P. intermedia and characterize its O-glycoproteome. Our cryoET analysis unveiled the ultrastructural details of the cell envelope and outer membrane vesicles (OMVs) of P. intermedia. We observed an electron-dense surface layer surrounding both cells and OMVs. The OMVs were often large (>200 nm) and presented two types, with lumens being either electron-dense or translucent. LC-MS/MS analyses of P. intermedia fractions led to the identification of 1655 proteins, which included 62 predicted T9SS cargo proteins. Within the glycoproteome, we identified 443 unique O-glycosylation sites within 224 glycoproteins. Interestingly, the O-glycosylation motif exhibited a broader range than reported in other species, with O-glycosylation found at D(S/T)(A/I/L/M/T/V/S/C/G/F/N/E/Q/D/P). We identified a single O-glycan with a delta mass of 1531.48 Da. Its sequence was determined by MS2 and MS3 analyses using both collision-induced dissociation and high-energy collisional dissociation fragmentation modes. After partial deglycosylation with trifluoromethanesulfonic acid, the O-glycan sequence was confirmed to be dHex-dHex-HexNAc (HPO3 -C6 H12 O5 )-dHex-Hex-HexA-Hex(dHex). Bioinformatic analyses predicted the localization of O-glycoproteins, with 73 periplasmic proteins, 53 inner membrane proteins, 52 lipoproteins, 26 outer membrane proteins, and 14 proteins secreted by the T9SS.
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Glicoproteínas , Espectrometria de Massas em Tandem , Glicosilação , Prevotella intermedia/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem/métodos , Proteínas de Membrana/metabolismo , Proteoma/metabolismo , PolissacarídeosRESUMO
Coluria longifolia Maxim (C. longifolia) is a Chinese folk medication commonly used to treat arthritis and joint pain. Literatures have reported that C. longifolia has significant anti-inflammatory, analgesic and antipyretic effects. The aim of this research was to assay the effective fractions of C. longifolia (EFCL) against rheumatoid arthritis (RA) and to elucidate its anti-RA mechanism on a preliminary basis. The rat model of collagen-induced arthritis (CIA) was established. The therapeutic effects of different fractions in vivo were evaluated by body weight changes, a foot swelling score, inflammatory factors and histopathological examination. The mechanism of EFCL was investigated by activity of oxidative stress related enzyme, qPCR and Western blotting tests. In vivo results showed that total extraction (TE) and n-butanol fraction (NF) could significantly alleviate the symptoms of RA, decrease the levels of IL-6 and TNF-α (P < 0.01), and improve histopathological injury. The mechanism study showed that SOD level was significantly increased with MDA level decreased in the NF group. The upregulated proteins and mRNA expression levels of Nrf2, HO1 and NQO1 after TE and NF administration suggested that the anti-arthritic effect may be related to the Nrf2 signaling pathway and downstream HO1 and NQO1. In conclusion, this study confirmed that C. longifolia is capable of treating RA with NF as the main effective fraction. Its anti-RA action may be associated with Nrf2 signaling pathway and downstream HO1 and NQO1.
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Objective To improve the detection ability of laboratories, and to identify possible technical defects in the detection of dichloroacetic acid and trichloroacetic acid in drinking water. Methods A number of laboratories were organized to conduct interlaboratory determination of dichloroacetic acid and trichloroacetic acid in drinking water. Prefabricated standard series and intermediate samples were distributed. Data of determination were collected and statistically analyzed to evaluate the detection results. Results The slopes of dichloroacetic acid and trichloroacetic acid working curves were analyzed by Grubbs test. The analysis results showed that there were 1 outlier in the dichloroacetic acid data and 3 outliers in the trichloroacetic acid data, respectively. The determination results of the spiked samples of dichloroacetic acid and trichloroacetic acid were 1.5 and 4 times the actual value, respectively. Conclusion This investigation reveals that there exist some technical problems in the direct determination of dichloroacetic acid and trichloroacetic acid by gas chromatography, such as inappropriate selection of chromatographic conditions and injection port flow control, and incorrect way of spiking internal standards.
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Parvalbumin interneurons belong to the major types of GABAergic interneurons. Although the distribution and pathological alterations of parvalbumin interneuron somata have been widely studied, the distribution and vulnerability of the neurites and fibers extending from parvalbumin interneurons have not been detailly interrogated. Through the Cre recombinase-reporter system, we visualized parvalbumin-positive fibers and thoroughly investigated their spatial distribution in the mouse brain. We found that parvalbumin fibers are widely distributed in the brain with specific morphological characteristics in different regions, among which the cortex and thalamus exhibited the most intense parvalbumin signals. In regions such as the striatum and optic tract, even long-range thick parvalbumin projections were detected. Furthermore, in mouse models of temporal lobe epilepsy and Parkinson's disease, parvalbumin fibers suffered both massive and subtle morphological alterations. Our study provides an overview of parvalbumin fibers in the brain and emphasizes the potential pathological implications of parvalbumin fiber alterations.
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Camundongos , Animais , Epilepsia do Lobo Temporal/patologia , Parvalbuminas/metabolismo , Doença de Parkinson/patologia , Neurônios/metabolismo , Interneurônios/fisiologia , Modelos Animais de Doenças , Encéfalo/patologiaRESUMO
ObjectiveTo establish a method for the determination of 8 volatile halogenated hydrocarbons in drinking water, including vinyl chloride, trichloroethylene, tetrachloroethylene, tetrachloromethane, chloroform, dichlorobromomethane, dichlorodibromomethane, and tribromomethane by headspace thermal desorption-gas mass spectrometry. MethodsThe water sample was kept in the headspace bottle at 60 ℃ for 40 min, and the volatile matter was transferred to the cold trap,subjected to thermal desorption, then analyzed by gas chromatography-mass spectrometry. ResultsThe linear ranges were 0.2‒20.0 μg·L-1 for vinyl chloride, 0.1‒20.0 μg·L-1 for chloroform, 0.02‒20.00 μg·L-1 for tetrachloromethane, 0.2‒20.0 μg·L-1 for trichloroethylene, 0.3‒20.0 μg·L-1 for dichlorobromomethane, 0.1‒20.0 μg·L-1 for tetrachloroethylene, 0.4‒20.0 μg·L-1 for dichlorodibromomethane, and 1.0‒20.0 μg·L-1 for tribromomethane. All the correlation coefficients were more than 0.997. The respective quantitative limits were 0.162, 0.073, 0.016, 0.184, 0.270, 0.071, 0.356 and 0.813 μg·L-1, and the respective recoveries were 98.0%‒101.0%, 102.0%‒110.0%, 99.2%‒101.0%, 95.5%‒96.2%, 96.0%‒102.0%, 100.0%‒102.0%, 99.0%‒105.0%, and 94.0%‒103.0%. ConclusionThe method is simple, sensitive, rapid, accurate and reliable, so it is applicable for the determination of 8 kinds of volatile halogenated hydrocarbons in drinking water.
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A large number of basic and clinical studies have shown that the Chinese herbs with promoting blood circulation and resolving phlegm effects could prevent and treat myocardial ischemia-reperfusion injury(MIRI) by regulating lipid metabolism. But its mechanism is not yet clear. The studies show that mitochondrial DNA (mtDNA), microRNAs and lipid metabolism participate in the whole process of MIRI and affect the prognosis. mtDNA mutation is the primary factor to cause myocardial ischemia and reperfusion myocardial cell damage. microRNAs aggravate or reduce MIRI injury by down-regulating or up-regulating related genes expression, while miR-33, as a key regulator of cholesterol transport, regulates lipid metabolism through CROT, PGC-1α, AMPK and other genes located in the mitochondria. There are less studies on correlation between miR-33 and mtDNA, microRNAs. Therefore, further studies on the correlation between miR-33 and mtDNA, microRNAs, as well as the discussions on whether the traditional Chinese medicine (TCM) with promoting blood circulation and resolving phlegm effects could target miR-33 to regulate lipid metabolism and inducemt DNA mutations or deletions, would have important significance for the prevention and treatment of MIRI.
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Objective To apply the HS-GC method to measure eleven kinds of chlorobenzenes and hexachlorobutadiene in drinking water . Methods We put 10 mL water sample into a 20 mL vial containing 2.5 g sodium chloride .The vial was stirred at 80℃ for 15 mins prior to headspace sampling . Eleven kinds of chlorobenzenes were separated completely by Rtx-1 701 capillary column(30.00 m ×0.25 mm ×0.25 μm),detected by electron capture detectors . Results The linearity of the method ranged from 1.00-32.00 μg/L, 0.20-6.40 μg/L, 0.05-1.60 μg/L, 0.02-0.64 μg/L, 0.02-0.64 μg/L and 0 .01-0 .32 μg/L for dichlorobenzene isomers , trichlorobenzene isomers , tetrachlorobenzene isomers , pentachlorobenzene , hexachlorobenzene and hexachlorobutadiene .In case of a 10 mL water sample , the lowest detected range of mass concentration was 0.001 62-0.262 00 μg/L.The additional standard recovery rate of finished water samples was in the range of 80%-119%with the relative standard deviation (RSD) in the range of 2.24%-4.99%. Conclusion This method is simple, fast, sensitive and needs no organic solvents .It is suitable for measuring both chlorobenzene compounds and hexachlorobutadiene in drinking water simultaneously .
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Objective To develop the methods for determination of nitromethane,nitroethane,1-nitropropane,2-nitropropane in the air of workplace. Methods Nitromethane,nitroethane,1-nitropropane,2-nitropropane in the air of workplace were collected by active carbon tube,desorbed in ethyl acetate solution and detected by capillary gas chromatography (GC-FID). Results The linear concentration range of nitromethane,nitroethane,1-nitropropane,2-nitropropane was 43.2-345.3,177.6-1 421.0,68.5-547.7,24.1-192.4 ?g/ml respectively and the relative standard deviation was 1%-5%. Sampling efficiency was 100%,desorption efficiency was 91%-93%. The sample could be resaved at 4-10 ℃ for 5-7 days. Conclusion The method is applicable to determination of nitromethane,nitroethane,1-nitropropane,2-nitropropane in the air of workplace.