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1.
Cancer Res ; 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32156778

RESUMO

Immunotherapies targeting programmed cell death protein 1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1) immune checkpoints represent a major breakthrough in cancer treatment. PD-1 is an inhibitory receptor expressed on the surface of activated T-cells that dampens T-cell receptor (TCR)/CD28 signaling by engaging with its ligand PD-L1 expressed on cancer cells. Despite the clinical success of PD-1 blockade using monoclonal antibodies, most patients do not respond to the treatment, and the underlying regulatory mechanisms of PD-1 remain incompletely defined. Here we show that PD-1 is extensively N-glycosylated in T cells and the intensities of its specific glycoforms are altered upon TCR activation. Glycosylation was critical for maintaining PD-1 protein stability and cell surface localization. Glycosylation of PD-1, especially at the N58 site, was essential for mediating its interaction with PD-L1. The monoclonal antibody STM418 specifically targeted glycosylated PD-1, exhibiting higher binding affinity to PD-1 than FDA-approved PD-1 antibodies, potently inhibiting PD-L1/PD-1 binding, and enhancing anti-tumor immunity. Together these findings provide novel insights into the functional significance of PD-1 glycosylation and offer a rationale for targeting glycosylated PD-1 as a potential strategy for immunotherapy.

2.
Int J Nanomedicine ; 15: 215-226, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32021175

RESUMO

3D printing, as a driving force of innovation over many areas, brings numerous manufacturing methods together from the macro to nano scales. New revolutionary materials (such as polymeric materials and natural biomaterials) can be produced into unique 3D printed nanostructures. The morphology and functionality of various 3D printing methods as well in vitro and in vivo results of their use towards regenerating bone are discussed in this review. This review further focuses nano scale 3D bioprinting technology for bone tissue engineering, mainly including recent progress in research on technical materials and methods, typical applications, and crucial achievements; explaining the scientific and technical challenges for bone tissue fabrication; and describing micro-nano scale 3D printing application prospects, development directions, and trends for the future for this field to realize its full potential.

3.
BMC Infect Dis ; 20(1): 167, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-32087689

RESUMO

BACKGROUND: Even though enterococci can cause serious infections in multiple sites, they are a rare cause of pneumonia. We reported a uremic patient with vancomycin-resistant E. faecium (VRE-fm) pneumonia, possibly related to epileptic seizures. CASE PRESENTATION: A 57-year old man with uremia on hemodialysis was admitted to the hospital with complaint of recurrent epileptic seizures, followed by a two-week history of recurrent fever and cough with purulent sputum. Chest CT demonstrated multiple exudation of both lungs. He was diagnosed as community acquired pneumonia. Despite antibiotic combination therapy, abnormal chest shadows aggravated. Sputum and blood cultures were initially negative, but later blood culture grew VRE-fm. We suspected aspiration of gastrointestinal content induced by epilepsy as the most likely mechanism. The patient was successfully treated with a four-week course of linezolid according to the antibiotic susceptibility testing. CONCLUSIONS: Physicians should consider multi-drug resistant organisms such as VRE in uremic patients with pneumonia that fails to resolve with broad-spectrum antibiotics, especially in the cases with aspiration induced by epilepsy, immunocompromised conditions, and repeated or prolonged hospitalizations.

4.
Int J Nanomedicine ; 15: 513-519, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32099353

RESUMO

Background: In recent years, numerous bacteria have become resistant to conventional antibiotics. Fortunately, an increasing body of research indicates that through the addition of specific metabolites (like sugars), the antibacterial activity of certain drugs can be enhanced. A new type of self-assembled nano-peptide amphiphile (SANPA) was designed in this study to treat antibiotic-resistant bacterial infections and to reduce the use of antibiotics. Methods: Here, SANPAs were self-assembled into nanorod structures with a diameter of ca. 10.5 nm at concentrations greater than the critical micelle concentration (CMC) of 44.67 µM. Both Gram-positive and Gram-negative bacteria were treated with SANPAs with fructose supplementation. Results: After a 30-min fructose pre-incubation, SANPAs reduced bacteria growth relative to non-fructose treatments at all concentrations. Cytotoxicity assays indicated that the presence of fructose seemed to slightly ameliorate the cytotoxic effect of the treatment on model human fetal osteoblasts (or bone-forming cells) and human dermal fibroblasts. Conclusion: We demonstrated here that SANPAs-like nanomaterials have a promising potential to treat antibiotic-resistant bacteria, especially when added to fructose, potentially limiting their associated infections.

5.
Chemosphere ; 243: 125342, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31995865

RESUMO

This study investigated an alternative carbon source derived from maize cobs (MCs) to enhance nitrogen removal in saline constructed wetlands (SCWs). The main objectives were to select the proper pretreatment method of MCs for rapid carbon release; and to investigate the effects of maize cob pieces (i.e. MCP) and three addition levels of maize cob lixiviums (i.e. L-MCL, M-MCL and H-MCL) on nitrogen purification performance and microbial characteristics of SCWs. Results showed NaOH pretreatment enhanced carbon release of MCs in seawater (from 7.5 ± 0.4 mgCOD g-1 to 16.4 ± 0.2 mgCOD g-1). The 80-d trial showed SCWs with M-MCL addition performed well on nitrogen removal: NO3-N, 88.8 ± 11.6%; NO2-N, 91.1 ± 3.5%; TAN, 96.5 ± 1.6%; TIN, 89.8 ± 10.4%; with 2 mg L-1 effluent COD. Denitrification parameters confirmed MCL to be a high quality carbon source: denitrification potential (PDN) = 0.16 gN gCOD-1; heterotrophy anoxic yield coefficient (YH) = 0.54 gCOD gCOD-1. The MCP and H-MCL treatments improved substrate dehydrogenase activity, indicating a higher microbial activity in these SCWs. Sequencing analysis revealed that, regardless of addition manners, carbon sources from MCs changed the rhizosphere microbial community. At genus level, Anaerophaga (10.1%), Granulosicoccus (8.2%) and Sulfurimonas (6.6%) dominated in SCWs under MCP treatment. Increased MCL addition levels improved the relative abundance of Vibrio, Malonomonas and Caldithrix, suggesting the enhancement of denitrification. Relative high proportions of Desulfotignum and Desulfovibrio, and Sulfurimonas were observed in MCP and H-MCL SCWs, implying that sulfate reduction occurred in SCWs with excess carbon sources.

6.
Biomed Chromatogr ; 34(4): e4794, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31944362

RESUMO

Just as natural saponins transform into aglycones, secondary glycosides and their derivatives using biotransformation technology, steroidal saponins may also undergo similar transformation after stir-frying. The purpose of this study was to elucidate the variations and the reasons for these variations in the contents of steroidal saponins in Fructus Tribuli (FT) during a stir-frying treatment. Stir-fried FT was processed in different time-temperature conditions. An UHPLC-MS/MS method was established and fully validated for quantitative analysis. In addition, the simulation processing products of tribuluside A, terrestroside B, terrestrosin K, terrestrosin D and 25R-tribulosin were determined by qualitative analysis using UHPLC-Q-TOF-MS. The established UHPLC-MS/MS method provides a rapid, flexible, and reliable method for the quality assessment of FT. The present study revealed that furostanol saponins with a C22-OH group could transform into corresponding furostanol saponins with a C-20-C-22 double bond (FSDB) via dehydroxylation. Additionally, FSDB could be successively converted into its secondary glycosides via a deglycosylation reaction. The transformation of spirostanol saponins into corresponding aglycones via deglycosylation led to a decrease in spirostanol saponins and an increase in aglycones. The results of this research provided scientific evidence of variation and structural transformation among steroidal saponins. These findings might be helpful for elucidating the processing mechanism of FT.

7.
J Neurosci Methods ; 334: 108535, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31972184

RESUMO

BACKGROUND: The genetically encoded calcium (Ca2+) sensor GCaMP6 has been widely used for imaging Ca2+ transients in neuronal somata, dendrites, and synapses. NEW METHOD: Here we describe five new transgenic mouse lines expressing GCaMP6F (fast) or GCaMP6S (slow) in the central and peripheral nervous system under the control of theThy1.2 promoter. RESULTS: These transgenic lines exhibit stable and layer-specific expression of GCaMP6 in multiple brain regions. They have several unique features compared to existing Thy1.2-GCaMP6 mice, including sparse expression of GCaMP6 in layer V pyramidal neurons of the cerebral cortex, motor neurons in the spinal cord, as well as sensory neurons in dorsal root ganglia (DRG). We further demonstrate that these mouse lines allow for robust detection of Ca2+ transients in neuronal somata and apical dendrites in the cerebral cortex of both anesthetized and awake behaving mice, as well as in DRG neurons. COMPARISON WITH EXISTING METHOD(S): These transgenic lines allows Ca2+ imaging of dendrites and somas of pyramidal neurons in specific cortical layers that is difficult to achieve with existing methods. CONCLUSIONS: These GCaMP6 transgenic lines thus provide useful tools for functional analysis of neuronal circuits in both central and peripheral nervous systems.

8.
Stem Cells Dev ; 29(4): 212-221, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31801411

RESUMO

In this study, the roles of exosomes (Exo) from bone marrow mesenchymal stem cells (BMSCs) in attenuating early brain injury (EBI) in rat brain after subarachnoid hemorrhage (SAH) had been investigated. The male Sprague-Dawley rats (300-350 g) were used to establish the SAH model using endovascular perforation method. The animals were randomly divided into three groups: sham (n = 25), SAH+PBS (n = 42), and SAH+Exo groups (n = 33). At 1 h after SAH, Exo or phosphate-buffered saline (PBS) was administered by femoral vein injection. The effects of Exo on the mortality, neurological function, brain water content, and blood-brain barrier (BBB) were explored. Furthermore, the expressions of miRNA129-5p and high-mobility group box 1 protein (HMGB1) after Exo treatment were also detected. In addition, immunohistochemistry and western blot were applied to investigate the mechanism of Exo's effects. The results indicated that Exo could improve the neurological functions, reduce brain water content and maintain BBB integrity after SAH. After Exo treatment, the expression of miRNA129-5p was significantly increased, whereas the RNA level of HMGB1 was decreased. The protein levels of proinflammatory and proapoptosis factors, such as HMGB1, Toll-like receptor-4 (TLR4), tumor necrosis factor-α, and p53, were increased after SAH, which were significantly declined after Exo application. The results indicated that Exo from BMSCs could alleviate EBI after SAH through miRNA129-5p's anti-inflammation and antiapoptosis effects through quenching the activity of HMGB1-TLR4 pathway.

9.
Brain Behav Immun ; 83: 180-191, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31604143

RESUMO

Microglia are resident immune cells of the central nervous system (CNS). The exact role of microglia in CNS disorders is not clear due to lack of tools to discriminate between microglia and infiltrating myeloid cells. Here, we present a novel reporter mouse model targeting a microglia-specific marker, TMEM119, for studying microglia in health and disease. By placing a reporter cassette (GSG-3xFlag-P2A-tdTomato) between the coding sequence of exon 2 and 3'UTR of the Tmem119 gene using CRISPR/Cas9 technology, we generated a Tmem119-tdTomato knock-in mouse strain. Gene expression assay showed no difference of endogenous Tmem119 in the CNS of Tmem119tdTomato/+ relative to wild-type mice. The cells expressing tdTomato were recognized by immunofluorescence staining using commercially available anti-TMEM119 antibodies. Additionally, immunofluorescence and flow cytometry techniques revealed that tdTomato+ cells are detected throughout the CNS, but not in peripheral tissues of Tmem119tdTomato/+ mice. Aging does not influence TMEM119 expression as tdTomato+ cells were detectable in the CNS of older mice (300 and 540 days old). Further immunofluorescence characterization shows that tdTomato+ cells colocalize with Iba1+ cells in the brain, but not with neurons, astrocytes or oligodendrocytes. Moreover, flow cytometry analysis of brain tissues of adult mice demonstrates that the majority of microglia CD45loCD11b+ cells (96.3%) are tdTomato-positive; and a minority of infiltrating CD45hiCD11b+ myeloid cells (5.3%) are also tdTomato-positive, which we further characterized and found that tdTomato expression is in part of choroid plexus macrophages but not in meningeal and perivascular macrophages. Functionally, using an acute injury model, we measured time-lapse activation of tdTomato-labeled microglia by transcranial two-photon microscopy in live Tmem119tdTomato/+ mice. Taken together, the Tmem119-tdTomato reporter mouse model is a valuable tool to specifically study the role of microglia in health and disease.

10.
Acta Neurochir Suppl ; 127: 59-64, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31407064

RESUMO

BACKGROUND: It is reported that the expression of aquaporin4 (AQP4) in the brain is increased and leads to the brain edema after subarachnoid hemorrhage (SAH). In this study, by using AQP4 knockout rat model, the opposite role of AQP4 in early brain injury following SAH through modulation of interstitial fluid (ISF) transportation in the brain glymphatic system had been explored. METHODS: The SAH model was established using endovascular perforation method, the AQP4 knockout rat model was generated using TALENs (transcription activator-like (TAL) effector nucleases) technique. The animals were randomly divided into four groups: sham (n = 16), AQP4-/-sham (n = 16), SAH (n = 24), and AQP4-/-SAH groups (n = 27). The roles of AQP4 in the brain water content and neurological function were detected. In addition, immunohistochemistry and Nissl staining were applied to observe the effects of AQP4 on the blood-brain barrier (BBB) integrity and the loss of neurons in the hippocampus. To explore the potential mechanism of these effects, the distribution of Gd-DTPA (interstitial fluid indicator) injected from cisterna magna was evaluated with MRI. RESULTS: Following SAH, AQP4 knockout could significantly increase the water content in the whole brain and aggravate the neurological deficits. Furthermore, the loss of neuron and BBB disruption in hippocampus were also exacerbated. The MRI results indicated that the ISF transportation in the glymphatic system of AQP4 deficit rat was significantly injured. CONCLUSION: AQP4 facilitates the ISF transportation in the brain to eliminate the toxic factors; AQP4 knockout will aggravate the early brain injury following SAH through impairment of the glymphatic system.


Assuntos
Aquaporina 4 , Edema Encefálico , Lesões Encefálicas , Hemorragia Subaracnóidea , Animais , Aquaporina 4/fisiologia , Encéfalo , Lesões Encefálicas/etiologia , Técnicas de Inativação de Genes , Sistema Glinfático , Ratos , Hemorragia Subaracnóidea/genética , Hemorragia Subaracnóidea/patologia
11.
Oxid Med Cell Longev ; 2019: 2193019, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885777

RESUMO

Ca2+/calmodulin-dependent protein kinase II (CaMKII), regulated by inhibitor 1 of protein phosphatase 1 (I1PP1), is vital for maintaining cardiovascular homeostasis. However, the role and mechanism of I1PP1 against hypoxia-reoxygenation (H/R) injury in cardiomyocytes remain a question. In our study, after I1PP1 overexpression by adenovirus infection in the neonatal cardiomyocytes followed by hypoxia for 4 h and reoxygenation for 12 h, the CaMKIIδ alternative splicing subtype, ATP content, and lactate dehydrogenase (LDH) release were determined. CaMKII activity was evaluated by phosphoprotein phosphorylation at Thr17 (p-PLB Thr17), CaMKII phosphorylation (p-CaMKII), and CaMKII oxidation (ox-CaMKII). Reactive oxygen species (ROS), mitochondrial membrane potential, dynamin-related protein 1 (DRP1), and optic atrophy 1 (OPA1) expressions were assessed. Our study verified that I1PP1 overexpression attenuated the CaMKIIδ alternative splicing disorder; suppressed PLB phosphorylation at Thr17, p-CaMKII, and ox-CaMKII; decreased cell LDH release; increased ATP content; attenuated ROS production; increased mitochondrial membrane potential; and decreased DRP1 expression but increased OPA1 expression in the cardiomyocytes after H/R. Contrarily, CaMKIIδ alternative splicing disorder, LDH release, ATP reduction, and ROS accumulation were aggravated after H/R injury with the I1PP1 knockdown. Collectively, I1PP1 overexpression corrected disorders of CaMKIIδ alternative splicing, inhibited CaMKII phosphorylation, repressed CaMKII oxidation, suppressed ROS production, and attenuated cardiomyocyte H/R injury.

12.
Inorg Chem ; 58(22): 15590-15601, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31697484

RESUMO

Photocatalytic reduction of CO2 by semiconductors is of great significance in generating value-added fuels. Here, we construct a novel S-C-S heterojunction constituted of MoS2/SnS2/r-GO by a simple solvothermal method. The prepared MoS2/SnS2/r-GO showed significant photoexcitation of photosensitive oxygen (ROS) by electron spin resonance spectroscopy, demonstrating that superoxide radicals (•O2-), pores, and hydroxyl radicals (•OH) are the main active species. The constructed S-C-S heterojunction has a multilevel electron transport mechanism and synergistic effect, which provides the possibility of producing more organic fuel. The photocatalytic materials were characterized by XRD, XPS, SEM, TEM, PL, etc. As a result, the atomic layer MoS2/SnS2/r-GO heterojunction exhibited a CO formation rate of 68.53 µmol g-1 h-1 and a CH4 formation rate of 50.55 µmol g-1 h-1, respectively. This work opens up new prospects for the formation of heterojunctions of chalcogenide transition-metal sulfides.

13.
Front Microbiol ; 10: 2137, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31608022

RESUMO

Extracellular enzymes, initiating the degradation of organic macromolecules, are important functional components of marine ecosystems. Measuring in situ seawater extracellular enzyme activity (EEA) can provide fundamental information for understanding the biogeochemical cycling of organic matter in the ocean. Here we investigate the patterns of EEA and the major factors affecting the seawater EEA of Chinese marginal seas. The geographic distribution of EEA along a latitudinal transect was examined and found to be associated with dissolved organic carbon. Compared with offshore waters, inshore waters had higher enzyme activity. All the tested substrates were hydrolyzed at different rates and phosphatase, ß-glucosidase and protease contributed greatly to summed hydrolysis rates. For any particular enzyme activity, the contribution of dissolved to total EEA was strongly heterogenous between stations. Comparisons of hydrolysis rates of the polymers and their corresponding oligomers suggest that molecule size does not necessarily limit the turnover of marine organic matter. In addition, several typical enzyme-producing clades, such as Bacteroidetes, Planctomycetes, Chloroflexi, Roseobacter, Alteromonas, and Pseudoalteromonas, were detected in the in situ environments. These enzyme-producing clades may be responsible for the production of different enzymes. Overall, each enzyme was found to flexibly respond to environmental conditions and were linked to microbial community composition. It is likely that this activity will profoundly affect organic matter cycling in the Chinese marginal seas.

14.
Surg Neurol Int ; 10: 50, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31528388

RESUMO

Background: Our study shows that a membrane sealant/fiber fusogen polyethylene glycol (PEG) applied immediately on a sharp section of the spinal cord can mend the cord and lead to exceptional levels of motor recovery, with some animals almost normal. Materials and Methods: Before deploying such technology in man, long-term data in large mammals that exclude delayed complications (e.g., central pain), confirm the stability of motor recovery, and provide histological evidence of fiber regrowth are necessary. Here, we provide such evidence in dogs followed up over 6 months and in 2 cases up to 1 year along with imaging and histologic data. Results: We show that dogs whose dorsal cord has been fully transected recover locomotion after immediate treatment with a fusogen (PEG). No pain syndrome ensued over the long term. Diffusion tensor imaging magnetic resonance and histological, including immunohistochemical, data confirmed the re-establishment of anatomical continuity along with interfacial axonal sprouting. Conclusions: This study proves that a form of irreversible spinal cord injury (SCI) can effectively be treated and points out a way to treat SCI patients.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31511778

RESUMO

Joint contracture is increasingly regarded as a clinical problem that leads to irreversible dysfunction of the joint. It is a pathophysiological process following joint injury, which is marked by the activation of myofibroblasts. There is currently no effective treatment for the prevention of joint contracture. Curcumin is a polyphenol pigment extracted from turmeric, which possesses anti-inflammatory, antioxidative, and antitumor properties. In the present study, we demonstrated that curcumin exerts a protective effect against joint contracture via the inhibition of myofibroblast proliferation and migration in a time- and concentration-dependent manner. Moreover, we indicated that phosphatase and tension homolog (PTEN) was downregulated in myofibroblasts in vitro and in the contracture capsule tissues of patients in vivo. Additionally, western blot analysis revealed a negative correlation between the expression levels of PTEN and the fibrosis marker protein alpha smooth muscle cell actin. Methylation-specific PCR results suggested that curcumin was able to demethylate PTEN in a similar manner to the demethylation agent 5-azacytidine, increasing PTEN expression and further inhibiting phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling. In conclusion, our data illustrate part of the mechanism of curcumin inhibition in joint contracture. These results support the hypothesis that curcumin may potentially be used as a novel candidate for the treatment of joint contracture.

16.
Proc Natl Acad Sci U S A ; 116(38): 18983-18993, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31481614

RESUMO

Telomerase is an enzymatic ribonucleoprotein complex that acts as a reverse transcriptase in the elongation of telomeres. Telomerase activity is well documented in embryonic stem cells and the vast majority of tumor cells, but its role in somatic cells remains to be understood. Here, we report an unexpected function of telomerase during cellular senescence and tumorigenesis. We crossed Tert heterozygous knockout mice (mTert +/- ) for 26 generations, during which time there was progressive shortening of telomeres, and obtained primary skin fibroblasts from mTert +/+ and mTert -/- progeny of the 26th cross. As a consequence of insufficient telomerase activities in prior generations, both mTert +/+ and mTert -/- fibroblasts showed comparable and extremely short telomere length. However, mTert -/- cells approached cellular senescence faster and exhibited a significantly higher rate of malignant transformation than mTert +/+ cells. Furthermore, an evident up-regulation of telomerase reverse-transcriptase (TERT) expression was detected in mTert +/+ cells at the presenescence stage. Moreover, removal or down-regulation of TERT expression in mTert +/+ and human primary fibroblast cells via CRISPR/Cas9 or shRNA recapitulated mTert -/- phenotypes of accelerated senescence and transformation, and overexpression of TERT in mTert -/- cells rescued these phenotypes. Taking these data together, this study suggests that TERT has a previously underappreciated, protective role in buffering senescence stresses due to short, dysfunctional telomeres, and preventing malignant transformation.

17.
J Dairy Sci ; 102(12): 10838-10844, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31548063

RESUMO

Lactobacillus plantarum J26, a significant probiotic isolated from Chinese traditional fermented dairy products, exerts a positive immunomodulatory effect by regulating the expression of immune-related genes. We investigated expression of the cytokines IL-1α, IL-1ß, IL-6, and tumor necrosis factor-α in the intestinal tract of mice stimulated by L. plantarum J26. In vivo, these cytokines were upregulated, peaked on d 5, and then decreased to the control level, indicating that L. plantarum J26 could induce expression of the genes encoding these proinflammatory cytokines. Teichoic acids produced by L. plantarum are recognized as key immunomodulatory molecules involved in the regulation of the host immune response. To better understand the genetic basis of this immunomodulatory mechanism, we sequenced and analyzed the whole genome of L. plantarum J26. The genome of L. plantarum J26 contains a circular chromosome and 4 circular plasmids. Lactobacillus plantarum J26 was predicted to synthesize ribitol-type backbones of wall teichoic acid. Furthermore, orthologous average nucleotide identity (OrthoANI) values showed that the genome was highly similar (>98.00%) to other L. plantarum strains, especially to L. plantarum ST-III and JDM1. The genomic data of L. plantarum J26 provide a genetic basis to further elucidate its mechanism of immunoregulation and will facilitate its application in the functional dairy food industry.


Assuntos
Genoma Bacteriano , Lactobacillus plantarum/genética , Probióticos , Animais , Produtos Fermentados do Leite/microbiologia , Citocinas/metabolismo , Fatores Imunológicos/farmacologia , Lactobacillus plantarum/imunologia , Lactobacillus plantarum/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Probióticos/farmacologia , Ácidos Teicoicos/metabolismo , Sequenciamento Completo do Genoma
18.
Nat Commun ; 10(1): 3087, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300648

RESUMO

The dorsal root ganglia (DRG) contain the somas of first-order sensory neurons critical for somatosensation. Due to technical difficulties, DRG neuronal activity in awake behaving animals remains unknown. Here, we develop a method for imaging DRG at cellular and subcellular resolution over weeks in awake mice. The method involves the installation of an intervertebral fusion mount to reduce spinal movement, and the implantation of a vertebral glass window without interfering animals' motor and sensory functions. In vivo two-photon calcium imaging shows that DRG neuronal activity is higher in awake than anesthetized animals. Immediately after plantar formalin injection, DRG neuronal activity increases substantially and this activity upsurge correlates with animals' phasic pain behavior. Repeated imaging of DRG over 5 weeks after formalin injection reveals persistent neuronal hyperactivity associated with ongoing pain. The method described here provides an important means for in vivo studies of DRG functions in sensory perception and disorders.


Assuntos
Gânglios Espinais/diagnóstico por imagem , Microscopia Intravital/métodos , Percepção da Dor/fisiologia , Células Receptoras Sensoriais/fisiologia , Animais , Técnicas de Observação do Comportamento/instrumentação , Técnicas de Observação do Comportamento/métodos , Comportamento Animal/fisiologia , Cálcio/química , Feminino , Formaldeído/administração & dosagem , Formaldeído/toxicidade , Gânglios Espinais/citologia , Gânglios Espinais/fisiologia , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Microscopia Intravital/instrumentação , Masculino , Camundongos , Camundongos Transgênicos , Modelos Animais , Imagem Óptica/instrumentação , Imagem Óptica/métodos , Dor/induzido quimicamente , Dor/fisiopatologia , Fótons , Vigília
19.
Front Pharmacol ; 10: 786, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354497

RESUMO

Berberine is a plant alkaloid that can be extracted from many Chinese herbs. It has been reported that berberine could protect mice from ulcerative colitis, but the mechanism remains unclear. The current study's aim was to determine the potential mechanism by which berberine exhibits its anti-inflammatory function. Mice with colitis induced by dextran sulfate sodium (DSS) were administered with berberine at 50 mg/kg by gavage. Berberine significantly increased the proportion of regulatory T cells (Treg cells). The targeted metabolomics analysis was then performed to find that glutamine and glutamate metabolism played an important role in the process of regulating immune response. mTORC1 pathway was reported to closely relate with glutamine metabolism. As a result, the relative expression levels of downstream effector genes of mTORC were further determined, and data obtained showed that berberine could significantly increase the relative expression levels of S6K1 and 4EBP1. In addition, rapamycin was used to inhibit mTORC1 signaling, and it was found that colon length, disease associated index (DAI), and proportion of Treg cells of mice in the rapamycin-DSS group were not different from those of mice in the rapamycin/berberine-DSS group. Together, these results suggest that berberine exhibits significant protective effects against DSS colitis by activating the mTORC1 pathway to increase the proportion of Treg cells.

20.
Talanta ; 204: 182-188, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357280

RESUMO

We described an aptamer based and Mg2+ mediated free zone capillary electrophoresis-laser induced fluorescence (CE-LIF) assay for aflatoxin B1 (AFB1) detection. This CE-LIF assay applied an anti-AFB1 aptamer with a single fluorescein (FAM) label at 5' end and a short complementary DNA (cDNA). In the absence of AFB1, the cDNA hybridized with the aptamer probe and formed a duplex DNA. The use of running buffer containing MgCl2 allowed good isolation of the duplex DNA from the single stranded DNA in CE. We found introducing a biotin label on the cDNA further improved the isolation. When AFB1 existed in sample solution, the aptamer probe bound with AFB1, dissociating from the duplex DNA. Thus, the duplex DNA peak decreased, while the aptamer probe peak increased during CE-LIF analysis. We achieved detection of AFB1 by measuring the aptamer probe peak. The length of cDNA, the ratio of aptamer to cDNA, and the concentration of MgCl2 in sample buffer and separation buffer had great effect on the aptamer based CE-LIF assay. Under optimized conditions, the detection limit of AFB1 was 0.2 nM, and the dynamic range was from 0.2 nM to 500 nM. Limit of quantitation was 0.5 nM. This CE-LIF assay enabled detection of AFB1 spiked in diluted human serum, diluted human urine, and corn flour samples. This assay exhibits potential for wide application as it integrates the rapidity, high sensitivity, low sample consumption of CE-LIF analysis and the strengths of aptamer.


Assuntos
Aflatoxina B1/sangue , Aflatoxina B1/urina , Eletroforese Capilar/métodos , Contaminação de Alimentos/análise , Magnésio/química , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Biotina/química , DNA Complementar/química , DNA Complementar/genética , Farinha/microbiologia , Fluoresceínas/química , Fluorescência , Corantes Fluorescentes/química , Humanos , Limite de Detecção , Hibridização de Ácido Nucleico , Zea mays/microbiologia
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