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International Journal of Peptide Research and Therapeutics - Diabetes is a metabolic disorder caused by defects in insulin production and insulin activity. l-Carnosine is a dipeptide containing...  相似文献   
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Liu  Na  Wang  Shutao  Cheng  Qi  Pang  Bo  Lv  Jiangtao 《Plasmonics (Norwell, Mass.)》2021,16(4):1079-1088

The organic non-crystalline medium of 5,6-dichloro-2-[[5,6-dichloro-1-ethyl-3-(4-sulfobutyl)-benzimidazol-2-ylidene]-propenyl]-1-ethyl-3-(4-sulfobutyl)-benzimidazolium hydroxide (TDBC) is emerging as possible alternative plasmonic material for noble metal in visible region. In this paper, a novel long-range surface exciton-polariton (LRSEP) sensor based on TDBC film covered with graphene is reported. To enhance the imaging sensitivity, the thickness of TDBC film and the number of graphene layers are optimized. The result shows that the optimized imaging sensitivity is enhanced to 3243 RIU−1 when ns = 1.34. Compared with the traditional noble metal film-based sensor, the proposed LRSEP sensor demonstrates that the imaging sensitivity has been greatly improved. This is the first study of the TDBC film-based LRSEP sensor, which we hope to support the potential development of chemical sensing and bio-sensing.

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The skin secretions of amphibians are a rich source of bioactive peptides. We isolated chensirin-1 and chensirin-2 from the skin secretion of the Chinese frog Rana chensinensis. Sephadex-G-50 and RP-HPLC were employed to purify these peptides. The amino acid sequences of these peptides were VLPLVGNLLNDLLGE and IIPLPLGYFAKKT, respectively, as determined by Edman degradation. The molecular weights were 1578.7 and 1460.8 Da, respectively, as analyzed by HPLC-ESI-MS. The chensirin cDNA was cloned by 5′ and 3′ amplification of cDNA ends, synthesized and purified. The antibacterial activities of the chensirins were tested using minimum inhibitory concentration, the results indicated that chensirins inhibit the growth of gram-negative and gram-positive bacteria. Among them, chensirin-1 is a novel peptide with a higher antibacterial activity compared to other similar antimicrobial peptides. These low molecular weight peptides with good antimicrobial efficacy are considered potential sources for developing new antimicrobial agents to improve traditional drug resistance.

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Transforming growth factor-β (TGF-β) is known to promote tumor migration and invasion. Bone morphogenetic proteins (BMPs) are members of the TGF-β family expressed in a variety of human carcinoma cell lines. The role of bone morphogenetic protein 9 (BMP9), the most powerful osteogenic factor, in osteosarcoma (OS) progression has not been fully clarified. The expression of BMP9 and its receptors in OS cell lines was analyzed by RT-PCR. We found that BMP9 and its receptors were expressed in OS cell lines. We further investigated the influence of BMP9 on the biological behaviors of OS cells. BMP9 overexpression in the OS cell lines 143B and MG63 inhibited in vitro cell migration and invasion. We further investigated the expression of a panel of cancer-related genes and found that BMP9 overexpression increased the phosphorylation of Smad1/5/8 proteins, increased the expression of ID1, and reduced the expression and activity of matrix metalloproteinase 9 (MMP9) in OS cells. BMP9 silencing induced the opposite effects. We also found that BMP9 may not affect the chemokine (C-X-C motif) ligand 12 (CXCL12)/C-X-C chemokine receptor type 4 (CXCR4) axis to regulate the invasiveness and metastatic capacity of OS cells. Interestingly, CXCR4 was expressed in both 143B and MG63 cells, while CXCL12 was only detected in MG63 cells. Taken together, we hypothesize that BMP9 inhibits the migration and invasiveness of OS cells through a Smad-dependent pathway by downregulating the expression and activity of MMP9.  相似文献   
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The explosive Koi herpesvirus (KHV) epidemic has caused the deaths of a large number of carp and carp variants and has produced serious economic losses. The mirror carp (Cyprinus carpio var. specularis) exhibits strong environmental adaptability and its primary cells can be used to isolate KHV. This study utilized the tissue explant method to systematically investigate primary cell culture conditions for mirror carp snout and caudal fin tissues. We demonstrated that cells from these two tissue types had strong adaptability, and when cultured in Medium 199 (M199) containing 20% serum at 26 to 30°C, the cells from the snout and caudal fin tissues exhibited the fastest egress and proliferation. Inoculation of these two cell types with KHV-infected fish kidney tissues produced typical cytopathic effects; additionally, identification by electron microscopy, and PCR indicated that KHV could be isolated from both cell types.  相似文献   
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We report a facile one‐pot sonochemical approach to preparing highly water‐soluble Ag nanoclusters (NCs) using bovine serum albumin as a stabilizing agent and reducing agent in aqueous solution. Intensive electrogenerated chemiluminescence (ECL) was observed from the as‐prepared Ag (NCs) and successfully applied for the ECL detection of dopamine with high sensitivity and a wide detection range. A possible ECL mechanism is proposed for the preparation of Ag NCs. With this method, the dopamine concentration was determined in the range of 8.3 × 10–9 to 8.3 × 10–7 mol/L without the obvious interference of uric acid, ascorbic acid and some other neurotransmitters, such as serotonin, epinephrine and norepinephrine, and the detection limit was 9.2 × 10–10 mol/L at a signal/noise ratio of 3. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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We aimed to investigate the relationship between the synthesis of hydrogen sulfide (H2S) and the pancreatic acinar cell apoptosis in severe acute pancreatitis (SAP) rats, as well as analyse the potential apoptotic pathway involved in this process. Sixty rats had been equally divided into four groups: sham, SAP, SAP + sodium hydrosulfide (NaHS) and SAP + DL-propargylglycine (PAG). 24 h after SAP induction, all surviving animals of each group were sacrificed to collect blood and tissue samples for the following measurements: the level of serum H2S as well as the levels of tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), H2S synthesizing activity, CSE mRNA and protein expression, maleic dialdehyde (MDA) and myeloperoxidase (MPO) activity, the expression of Bax, Bcl-2, caspase-3, -8 and -9, the release of cytochrome c and the activation of nuclear factor-kappa B (NF-κB), ERK1/2, JNK1/2 and p38 in pancreas. Furthermore, in situ detection of cell apoptosis was examined and the severity of pancreatic damage was analyzed by pathological grading and scoring. Results Significant differences in every index except IL-10 had been found between the SAP, NaHS and PAG groups (P < 0.05). Treatment with PAG obviously induced the pancreatic acinar cell apoptosis as well as improved all the pathological changes and inflammatory parameters. In contrast, administration of NaHS significantly attenuated apoptosis in the pancreas and aggravated the severity of pancreatic damage. Moreover, the expressions of caspase-3, -8, -9 and the release of cytochrome c were all increased in the apoptotic cells, and the activity of NF-κB as well as the phosphorylation of ERK1/2, JNK1/2 and p38 decreased accompanying with the reduction of the serum H2S level. H2S plays a pivotal role in the regulation of pancreatic acinar cell apoptosis in SAP rats. The present results showed that inhibition of H2S synthesis provided protection for SAP rats via inducing acinar cell apoptosis. This process acted through both extrinsic and intrinsic apoptotic pathways, and may be regulated by reducing the activity of NF-κB.  相似文献   
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