97 research outputs found

    Glycan Sequence‐Dependent Nod2 Activation Investigated by Using a Chemically Synthesized Bacterial Peptidoglycan Fragment Library

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    Nucleotide oligomerization domain‐containing protein 2 (Nod2), an innate immune receptor, recognizes bacterial cell‐wall peptidoglycan (PGN), the minimum ligand of which is muramyl dipeptide (MDP). Enzymatic digestion of PGN appears to be important for Nod2 recognition. PGN is degraded by muramidase or glucosamidase through a process that produces two types of glycan sequence; glycans containing GlcNAcβ(1→4)MurNAc or MurNAcβ(1→4)GlcNAc. In this report, a range of disaccharide or tetrasaccharide fragments of each sequence were chemically synthesized, and their activities in stimulating human Nod2 (hNod2) were investigated. The results reveal that hNod2 recognitions is dependent on the glycan sequence, as demonstrated by comparing the activities of glycans with the same peptide moieties. (MurNAcβ(1→4)GlcNAc) 2 ‐containing structures exhibited stronger activity than those containing (GlcNAcβ(1→4)MurNAc) 2 . The results suggest that differences in the enzymatic degradation process affect the host's immunomodulation process. To Nod off or on? Di‐ or tetrasaccharide fragments of muramidase and glucosamidase were chemically synthesized, and their abilities to stimulate human Nod2 were investigated. The results reveal that hNod2 recognition is glycan sequence‐dependent, and suggest that the peptidoglycan degradation process affects the host's immunomodulation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96737/1/cbic_201200655_sm_miscellaneous_information.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/96737/2/482_ftp.pd

    General Factors and Dental-Related Risk Factors for Postoperative Pneumonia or Infectious Complications: A Retrospective Study

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    Numerous studies report that perioperative oral care decreases the frequency of postoperative pneumonia or infection. However, no studies have analyzed the specific impact of oral infection sources on the postoperative course, and the criteria for preoperative dental care differ among institutions. This study aimed to analyze the factors and dental conditions present in patients with postoperative pneumonia and infection. Our results suggest that general factors related to postoperative pneumonia, including thoracic surgery, sex (male > female), the presence or absence of perioperative oral management, smoking history, and operation time, were identified, but there were no dental-related risk factors associated with it. However, the only general factor related to postoperative infectious complications was operation time, and the only dental-related risk factor was periodontal pocket (4 mm or higher). These results suggest that oral management immediately before surgery is sufficient to prevent postoperative pneumonia, but that moderate periodontal disease must be eliminated to prevent postoperative infectious complication, which requires periodontal treatment not only immediately before surgery, but also on a daily basis.Isomura E.T., Fujimoto Y., Matsukawa M., et al. General Factors and Dental-Related Risk Factors for Postoperative Pneumonia or Infectious Complications: A Retrospective Study. Journal of Clinical Medicine 12, 3529 (2023); https://doi.org/10.3390/jcm12103529

    Urine and plasma levels of uroguanylin and its molecular forms in renal diseases

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    Urine and plasma levels of uroguanylin and its molecular forms in renal diseases. Uroguanylin activates the intestinal and possibly the renal guanylate cyclase C receptor, and stimulates Cl− secretion. We developed a sensitive radioimmunoassay (RIA) for human uroguanylin and measured its concentration in the urine and plasma. Twenty-four-hour urinary excretion of immunoreactive (ir-) uroguanylin for persons with a high-salt diet (10 g/day) was 137.8 ± 14.4 pmol/day, significantly higher than that for persons with a low-salt diet (7 g/day, 95.1 ± 16.3 pmol/day, P < 0.05). There were significantly positive correlations between the urinary excretion of ir-uroguanylin and Na+, Cl−, K+ or cyclic GMP (cGMP). We demonstrated the presence of messenger RNA of guanylate cyclase C in the medulla of human kidney. The concentration of plasma ir-uroguanylin significantly correlated with that of serum creatinine (r = 0.71, P < 0.001). Biologically active uroguanylin-16 accounted for 99% of the endogenous uroguanylin molecules in normal urine and 60% in plasma, the remainder being the 10kDa precursor. The precursor content increased in the urine and plasma as the severity of renal impairment increased. These findings suggest that bioactive uroguanylin-16 is involved in the regulation of electrolyte homeostasis and that the kidney participates in the metabolism and excretion of uroguanylin

    The Peptide Sequence of Diacyl Lipopeptides Determines Dendritic Cell TLR2-Mediated NK Activation

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    Natural killer (NK) cells are lymphocyte effectors that are activated to control certain microbial infections and tumors. Many NK-activating and regulating receptors are involved in regulating NK cell function. In addition, activation of naïve NK cells is fundamentally triggered by cytokines or myeloid dendritic cells (mDC) in various modes. In this study, we synthesized 16 S-[2,3-bis(palmitoyl)propyl]cysteine (Pam2Cys) lipopeptides with sequences designed from lipoproteins of Staphylococcus aureus, and assessed their functional properties using mouse (C57BL/6) bone marrow-derived DC (BMDC) and NK cells. NK cell activation was evaluated by three criteria: IFN-γ production, up-regulation of NK activation markers and cytokines, and NK target (B16D8 cell) cytotoxicity. The diacylated lipopeptides acted as TLR2 ligands, inducing up-regulation of CD25/CD69/CD86, IL-6, and IL-12p40, which represent maturation of BMDC. Strikingly, the Pam2Cys lipopeptides induced mouse NK cell activation based on these criteria. Cell-cell contact by Pam2Cys peptide-stimulated BMDC and NK cells rather than soluble mediators released by stimulated BMDC induced activation of NK cells. For most lipopeptides, the BMDC TLR2/MyD88 pathway was responsible for driving NK activation, while some slightly induced direct activation of NK cells via the TLR2/MyD88 pathway in NK cells. The potential for NK activation was critically regulated by the peptide primary sequence. Hydrophobic or proline-containing sequences proximal to the N-terminal lipid moiety interfered with the ability of lipopeptides to induce BMDC-mediated NK activation. This mode of NK activation is distinctly different from that induced by polyI:C, which is closely associated with type I IFN-inducing pathways of BMDC. These results imply that the MyD88 pathway of BMDC governs an alternative NK-activating pathway in which the peptide sequence of TLR2-agonistic lipopeptides critically affects the potential for NK activation

    Best Thermoelectric Efficiency of Ever-Explored Materials

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    A thermoelectric device is a heat engine that directly converts heat into electricity. Many materials with a high figure of merit ZT have been discovered in anticipation of a high thermoelectric efficiency. However, there has been a lack of investigations on efficiency-based material evaluation, and little is known about the achievable limit of thermoelectric efficiency. Here, we report the highest thermoelectric efficiency using 13,353 published materials. The thermoelectric device efficiencies of 808,610 configurations are calculated under various heat-source temperatures (T_h) when the cold-side temperature is 300 K, solving one-dimensional thermoelectric integral equations with temperature-dependent thermoelectric properties. For infinite-cascade devices, a thermoelectric efficiency larger than 33% (~1/3) is achievable when T_h exceeds 1400 K. For single-stage devices, the best efficiency of 17.1% (~1/6) is possible when T_h is 860 K. Leg segmentation can overcome this limit, delivering a very high efficiency of 24% (~1/4) when T_h is 1100 K.Comment: 32 pages (main+table+figure captions+figures), 7 additional pages for 6 high resolution figures, Supporting Data file is not public ye

    Nod1 acts as an intracellular receptor to stimulate chemokine production and neutrophil recruitment in vivo

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    Nod1 is a member of family of intracellular proteins that mediate host recognition of bacterial peptidoglycan. To characterize immune responses mediated by Nod1, synthetic ligand compounds possessing enhanced ability to stimulate Nod1 were developed to study the function of Nod1. Stimulation of epithelial cells with Nod1 stimulatory molecules induced chemokines and other proinflammatory molecules that are important for innate immune responses and recruitment of acute inflammatory cells. Administration of Nod1 ligands into mice induced chemokines and recruitment of acute inflammatory cells, an activity that was abolished in Nod1-null mice. Microarray analysis revealed that Nod1 stimulation induces a restricted number of genes in intestinal epithelial cells compared with that induced by tumor necrosis factor (TNF) α. Nod1 stimulation did not induce TNFα, interleukin 12, and interferon γ, suggesting that the primary role of Nod1 is to induce the recruitment of immune cells. These results indicate that Nod1 functions as a pathogen recognition molecule to induce expression of molecules involved in the early stages of the innate immune response

    Erratum: Synthesis of glycerolipids containing simple linear acyl chains or aromatic rings and evaluation of their Mincle signaling activity (Chem. Commun. (2019) 55 (711–714) DOI: 10.1039/C8CC07322H)

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    金沢大学医薬保健研究域薬学系The authors regret that the structures of brartemicin and compounds 6a and b presented in Fig. 2 of the article were incorrect. The correct structures are depicted below. In addition, explanations of the R’ groups have been added below each compound. (Figure Presented). This journal is © The Royal Society of Chemistr

    Analysis of Causal Models of Diet for Patients with Head and Neck Cancer Receiving Particle Beam Therapy : Aiming to Increase Appetite

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    本研究は、粒子線治療を受ける頭頸部がん患者を対象として、食欲を向上するための食事に関する因果モデルを明らかにすることを目的とした。データ収集は147 名に対して食事に関する質問紙調査を40GyE の時点で実施し、構造方程式モデリングを用いて分析した。40 GyE の因果モデルは、時間的関係から【嗜好性によるおいしさ】と【口腔内を労りながらの食欲の向上】の間に直接因子として【口溶けの良い食感によるおいしさ】【あっさりとした味付けと風味豊かな匂いによるおいしさ】、間接因子として【刺激の少ない温度と滑らかな食形態によるおいしさ】【献立全体の工夫によるおいしさ】の媒介変数を位置づけてパスを設定した。さらにこのモデルでは、直接因子として【時間帯で変わる食事のおいしさ】が【口腔内を労りながらの食欲の向上】に影響するという因果関係も認められた。因果モデルの適合度指標は、GFI、AGFI がいずれも0.85 以上、RMSEA においても0.08 未満であり、モデル適合度は良好であった。以上より、因果モデルに示す特徴は、食欲の向上に資することが示唆された。departmental bulletin pape
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