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81.
Joanna Jeruzal-
witecka Edyta Borkowska Mateusz aszczych Zuzanna Nowicka Wioletta Pietruszewska 《International journal of molecular sciences》2022,23(13)
Studies have shown differences in TAS2R38 receptor expression in patients with chronic rhinosinusitis (CRS) compared to healthy controls. Known agonists of TAS2R38 stimulate epithelial cells, leading to robust intracellular nitric oxide (NO) production, which damages bacterial membranes, enzymes, and DNA, but also increases ciliary beat frequency. In this study we examined, using qRT-PCR, the expression of TAS2R38 receptor in nasal polyps (NP) of patients with CRS (N = 107) and in inferior turbinate mucosa (ITM) of patients with CRS and controls (N = 39), and confronted it with clinical features and the severity of the disease. The expression was shown in 43 (50.00%) samples of ITM in the study group (N = 107), in 28 (71.79%) in the control group (N = 39) (p = 0.037), and in 43 (46.24%) of NP. There were no differences in levels of the expression in all analyzed tissues. Patients who rated their symptoms at 0–3 showed higher TAS2R38 expression in ITM in comparison to the patients with 8–10 points on the VAS scale (p = 0.020). A noticeable, however not significant, correlation between the TAS2R38 expression in ITM and the Lund–Mackay CT score was shown (p = 0.068; R = −0.28). Patients with coexisting asthma had significantly higher receptor expression in the NP (p = 0.012). Our study is the first to confirm the presence of the TAS2R38 receptor in NP. Expression of the TAS2R38 receptor is reduced in the sinonasal mucosa in patients with more advanced CRS with NP. 相似文献
82.
Magdalene K. Ameka William N. Beavers Ciara M. Shaver Lorraine B. Ware Vern Eric Kerchberger Kelly Q. Schoenfelt Lili Sun Tatsuki Koyama Eric P. Skaar Lev Becker Alyssa H. Hasty 《International journal of molecular sciences》2022,23(13)
Adipocyte iron overload is a maladaptation associated with obesity and insulin resistance. The objective of the current study was to determine whether and how adipose tissue macrophages (ATMs) regulate adipocyte iron concentrations and whether this is impacted by obesity. Using bone marrow-derived macrophages (BMDMs) polarized to M0, M1, M2, or metabolically activated (MMe) phenotypes, we showed that MMe BMDMs and ATMs from obese mice have reduced expression of several iron-related proteins. Furthermore, the bioenergetic response to iron in obese ATMs was hampered. ATMs from iron-injected lean mice increased their glycolytic and respiratory capacities, thus maintaining metabolic flexibility, while ATMs from obese mice did not. Using an isotope-based system, we found that iron exchange between BMDMs and adipocytes was regulated by macrophage phenotype. At the end of the co-culture, MMe macrophages transferred and received more iron from adipocytes than M0, M1, and M2 macrophages. This culminated in a decrease in total iron in MMe macrophages and an increase in total iron in adipocytes compared with M2 macrophages. Taken together, in the MMe condition, the redistribution of iron is biased toward macrophage iron deficiency and simultaneous adipocyte iron overload. These data suggest that obesity changes the communication of iron between adipocytes and macrophages and that rectifying this iron communication channel may be a novel therapeutic target to alleviate insulin resistance. 相似文献
83.
Tatsuhide Hayashi Masaki Asakura Mayu Kawase Masakazu Matsubara Yasuaki Uematsu Akimichi Mieki Tatsushi Kawai 《International journal of molecular sciences》2022,23(13)
This study aimed to induce bone-like tissue from immature muscular tissue (IMT) in vitro using commercially available recombinant human bone morphogenetic protein (rhBMP)-2, rhBMP-4, and rhBMP-7, and then implanting this tissue into a calvarial defect in rats to assess healing. IMTs were extracted from 20-day-old Sprague-Dawley (SD) fetal rats, placed on expanded polytetrafluoroethylene (ePTFE) with 10 ng/μL each of rhBMP-2, BMP-4, and BMP-7, and cultured for two weeks. The specimens were implanted into calvarial defects in 3-week-old SD rats for up to three weeks. Relatively strong radiopacity was observed on micro-CT two weeks after culture, and bone-like tissue, comprising osteoblastic cells and osteoids, was partially observed by H&E staining. Calcium, phosphorus, and oxygen were detected in the extracellular matrix using an electron probe micro analyzer, and X-ray diffraction patterns and Fourier transform infrared spectroscopy spectra of the specimen were found to have typical apatite crystal peaks and spectra, respectively. Furthermore, partial strong radiopacity and ossification were confirmed one week after implantation, and a dominant novel bone was observed after two weeks in the defect site. Thus, rhBMP-2, BMP-4, and BMP-7 differentiated IMT into bone-like tissue in vitro, and this induced bone-like tissue has ossification potential and promotes the healing of calvarial defects. Our results suggest that IMT is an effective tissue source for bone tissue engineering. 相似文献
84.
Mithun Santra Yu-Chi Liu Vishal Jhanji Gary Hin-Fai Yam 《International journal of molecular sciences》2022,23(14)
A transparent cornea is paramount for vision. Corneal opacity is one of the leading causes of blindness. Although conventional corneal transplantation has been successful in recovering patients’ vision, the outcomes are challenged by a global lack of donor tissue availability. Bioengineered corneal tissues are gaining momentum as a new source for corneal wound healing and scar management. Extracellular matrix (ECM)-scaffold-based engineering offers a new perspective on corneal regenerative medicine. Ultrathin stromal laminar tissues obtained from lenticule-based refractive correction procedures, such as SMall Incision Lenticule Extraction (SMILE), are an accessible and novel source of collagen-rich ECM scaffolds with high mechanical strength, biocompatibility, and transparency. After customization (including decellularization), these lenticules can serve as an acellular scaffold niche to repopulate cells, including stromal keratocytes and stem cells, with functional phenotypes. The intrastromal transplantation of these cell/tissue composites can regenerate native-like corneal stromal tissue and restore corneal transparency. This review highlights the current status of ECM-scaffold-based engineering with cells, along with the development of drug and growth factor delivery systems, and elucidates the potential uses of stromal lenticule scaffolds in regenerative therapeutics. 相似文献
85.
按照测量不确定度评定的基本方法和程序对卫生纸抗张强度测量结果的不确定度进行了评定,不确定度来源主要是抗张力F-的重复性测量,其次为电子万能试验机校准和试样宽度;卫生纸抗张强度测量结果的扩展不确定度是1.6N/m,包含因子为2;在卫生纸抗张强度测量过程中,应均匀取样,并提高操作者的熟练程度。 相似文献
86.
The influences of vacuum impregnation (VI) on the tissue of mango cubes during atmospheric immersion in sucrose solution were investigated. Results showed that VI effectively facilitated water loss (WL) and sugar gain (SG) during the 300min immersion process, with increases of 20.59% and 31.26%, respectively. A pectin solubilization/degradation phenomenon was observed in the immersion process. The intercellular space and cross section area in the VI‐treated mango tissue increased immediately after being released to atmospheric pressure. And it was noted that after experiencing shrinkage‐relaxation period twice in the 300 min immersion process, the size of VI‐treated mango cells recovered to the original level of fresh ones. Major variations in WL, protopectin content, water soluble pectin content, firmness and microstructure of mango cubes appeared within the first 60 min. In addition, the firmness of mango cubes was positively correlated with the protopectin content (P < 0.01), but negatively correlated with WL and the water soluble pectin content (P < 0.01), indicating that WL and degradation of protopectin contributed greatly to the loss of firmness. 相似文献
87.
《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(2):272-277
The residue depletion profile of sulfachlorpyrazine was studied in healthy broilers after oral administration of Sulfatyf®, given at a dose of 50?mg sulfachlorpyrazine (SCP) per kg body weight once daily for 3 consecutive days. Twenty-five medicated broilers were slaughtered on the 5th, 10th, 14th and 16th day of post-medication, and muscle, fat with skin, liver and kidney tissues were sampled and analysed using an high-performance liquid chromatography (HPLC) method with satisfactory recovery (74.5%?±?2.9%) and specificity. The estimated values of LOD and LOQ were 18.40 and 55.70?ng?ml?1, respectively. On the 5th and 10th day of post-medication, the concentrations of SCP residue in all samples examined were higher than the corresponding MRLs established by the European Union and the highest SCP concentrations were measured in muscle. A maximum withdrawal time of 14 days was calculated to ensure consumer safety. 相似文献
88.
Intramuscular connective tissue obtained from Longissimus dorsi muscle of a 4-year-old beef carcass was treated with NaCl solutions of 2, 4, and 6% (w/v), and CaCl2 solutions of 50, 100, and 150 mM, and citric and lactic acid solutions of 0.5, 1.0, and 1.5% for three different marinating periods (24, 46, and 72 h). Changes in denaturation characteristics were investigated using differential scanning calorimetry and it was found that the denaturation onset temperature (To) and the denaturation peak temperature (Tp) increased as the NaCl concentration increased but decreased as the CaCl2 concentration increased, irrespective of marinating time. Lactic and citric acid decreased To to about 39°C, from over 60°C breaking the structure of fibrils. 相似文献
89.
ABSTRACT: A depth sensing indentation hardness test with an associated analysis is described as a convenient and simple technique for characterizing mechanical properties of food materials, such as hardness (H), elastic modulus (E), and an elasticity index (IE ), which represents the ratio of elastic to total deformation. Storage modulus (G') and loss tangent (tan§) of the selected model food material, a whey protein concentrate (WPC) gel, have also been determined using an oscillatory dynamic testing. Fractal dimension (D) and strain rate (or frequency) exponent (n) of the WPC gels were determined using both the indentation and dynamic test results. A good correlation between the results from the indentation and the dynamic tests was established. The effects of protein concentration, deformation rate, and chemical treatment on the mechanical properties of the WPC gels were clearly illustrated using the indentation test. 相似文献
90.
Evans Adei Kwadwo Forson-Adaboh 《Food Additives and Contaminants: Part B: Surveillance Communications》2013,6(2):100-105
Accumulation of toxic metals in liver, a rich natural source of essential elements, can present health risks to regular consumers of liver. A total of 35 fresh liver samples of cow, sheep, goat, pig, grass-cutter (Thryonomys swinderianus), gaint rat (Cricetomys gambianus), red deer (Cervus elaphus), chicken and antelope (Antilocapra americana) were obtained from three different markets in Accra and Kumasi, Ghana. Samples were analyzed using atomic absorption spectrometry and an automatic mercury analyzer. Levels of iron in the grass-cutter and pig of 500.5–645.4 mg kg?1 were the highest in the animal livers examined. Mn concentrations were highest in grass-cutter and rat liver, ranging 16.5–30.2 mg kg?1. The safe Cu and Zn permissible limits of 20 and 50 mg kg?1 were exceeded in 70 and 75% of the liver samples, respectively. Generally, for each animal group studied, at least 50% of the sample livers exceeded the Cd permissible limit of 0.5 mg kg?1. The levels of Pb, which ranged 1.3–13.8 mg kg?1, exceeded the proposed European Commission (EC) limit of 0.5 mg kg?1. Care must be taken by regular consumers of the iron-rich animal livers of grass-cutter, pig and rat because they also had the highest levels of Pb (in grass-cutter and pig) and Cd (in grass-cutter, rat and pig). The liver samples analyzed for Hg had values far below the permissible limit of 0.5 mg kg?1. 相似文献