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101.
The present study aimed to investigate the effects of a minimally invasive laser needle system (MILNS) on the acute progression of arthritis. Previous studies showed controversial clinical results regarding the effects of low-level laser therapy on arthritis, with the outcomes depending upon stimulation parameters such as laser wavelength and dosage. Based on the positive effects of MILNS on osteoporotic mice, we hypothesized that MILNS could potentially suppress the progression of arthritis owing to its biostimulation effects. Eight C57BL/6 mice with complete Freund’s adjuvant (CFA)-induced arthritis were used as acute progression arthritis models and divided into the laser and control groups (n?=?4 each). In the laser group, after minimally invasive laser stimulation, laser speckle contrast images (LSCIs) were obtained every 6 h for a total of 108 h. The LSCIs in the control group were obtained without laser stimulation. The effects of MILNS on the acute progression of arthritis were indirectly evaluated by calculating the paw area and the average laser speckle index (LSI) at the arthritis-induced area. Moreover, the macrophage population was estimated in the arthritis-induced area. Compared to the control group, the laser group showed (1) lower relative variations of the paw area, (2) lower average LSI in the arthritis-induced area, and (3) lower macrophage population in the arthritis-induced area. These results indicate that MILNS may suppress the acute progression of CFA-induced arthritis in mice and may thus be used as a potential treatment modality of arthritis in clinics.  相似文献   
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This study investigated wound contraction rates according to anatomical regions and wound morphology according to skin tension line in a micropig porcine model. Of the four animals used, skin tension morphology was determined in one pig. In the remaining three pigs, six pairs of full‐thickness skin excisions were created on the dorsum (six square and six circular). The wounds were grouped, Wounds #1 through #5, according to the skin tension line and anatomical regions: Wounds #1 and #2, cephalic; Wounds #4 and #5, caudal; and Wound #3, center. Wound sizes and contraction rates were calculated for 28 days. A static tension topography of the micropig dorsum was obtained. Excisional wounds deformed along the local tension vector and healed in this fashion. Wound contraction rates were significantly higher for cephalic wounds (p = 0.004). No significant difference in wound contraction rates were observed between square and circular wounds. Final wound morphology was related to the local tension vector and initial wound shape. Cephalic wounds contracted more quickly. Further studies are needed to characterize scar formation after primarily closed surgical wounds in relation to the newly established skin tension topography and to elucidate the mechanism behind the variable wound contraction rates in the cephalocaudal gradient.  相似文献   
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Cellular senescence is known to contribute to tissue aging, a variety of age-related diseases, tissue regeneration, and cancer. Therefore, aging intervention might be useful for prevention of aging as well as age-related disease. In this study, we investigated compounds from Polygonum aviculare to determine if they inhibited cellular senescence in human primary cells, human dermal fibroblasts (HDFs) and human umbilical vein endothelial cells (HUVECs). Ten compounds from P. aviculare were purified and their inhibitory effects on adriamycin-induced cellular senescence were measured by observing senescence-associated β-galactosidase (SA-β-gal) activity and reactive oxygen species. Among them, compound 9 (quercetin-3-O-β-d-glucuronide) showed inhibitory effects against cellular senescence in HDFs and HUVECs treated with adriamycin. Additionally, compound 9 rescued replicative senescence in HDFs and HUVECs. These data imply that compound 9 represses cellular senescence in human primary cells and might be useful for the development of dietary supplements or cosmetics that ameliorate tissue aging or aging-associated diseases.  相似文献   
107.
Two rapid and simple HPLC methods with UV detector to determine three main compounds (magnoflorine, spinosin and 6′′′-feruloyl spinosin) and evaporative light scattering detector (ELSD) to determine jujuboside A were developed for the chemical analyses of Zizyphi Semen. Magnoflorine, spinosin, and 6′′′-feruloyl spinosin were separated with an YMC J’sphere ODS-H80 column (250 mm × 4.6 mm, 4 μm) by the gradient elution followed by the isocratic elution using methanol with 0.1 % formic acid and water with 0.1 % formic acid as the mobile phase. The flow rate was 1.0 mL/min. Jujuboside A was separated by HPLC–ELSD with YoungJinBioChrom Aegispak C18-L column (250 mm × 4.6 mm, 5 μm) column in a gradient elution using methanol with 0.1 % formic acid (A) and water with 0.1 % formic acid as the mobile phase. These two methods were fully validated with respect to linearity, precision, accuracy, stability, and robustness. These HPLC methods were applied successfully to quantify four compounds in a Zizyphi Semen extract. The HPLC analytical methods were validated for pattern recognition analysis by repeated analysis of 91 seed samples corresponding to 48 Zizyphus jujuba var. spinosa (J01–J48) and 43 Zizyphus mauritiana (M01–M43). The results indicate that these methods are suitable for a quality evaluation of Zizyphi Semen.  相似文献   
108.
Electrospun nanofiber drug delivery systems have been studied using various techniques. Herein, we describe the fabrication of a drug-incorporating nanofiber. Drugs, such as proteins, peptide, antibodies, and small molecule drugs, can be loaded within or on the surface of nanofibers according to their properties. Hydrophobic drugs are directly dissolved with a polymer in an organic solvent before electrospinning. However, it is preferred to surface-immobilize bioactive molecules on nanofibers by physical absorption or chemical conjugation. Especially, chemically surface-immobilized proteins on a nanofiber mesh stimulate cell differentiation and proliferation. Using a dual electrospinning nozzle to create nanofiber sheet layers, which are stacked on top of one another, the initial burst release is reduced compared with solid nanofibers because of the layers. Furthermore, hybridization of electrospun nanofibers with nanoparticles, microspheres, and hydrogels is indirect drug loading method into the nanofibers. It is also possible to produce multi-drug delivery systems with timed programmed release.  相似文献   
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of COVID-19, is a readily transmissible and potentially deadly pathogen which is currently re-defining human susceptibility to pandemic viruses in the modern world. The recent emergence of several genetically distinct descendants known as variants of concern (VOCs) is further challenging public health disease management, due to increased rates of virus transmission and potential constraints on vaccine effectiveness. We report the isolation of SARS-CoV-2 VOCs imported into Australia belonging to the B.1.351 lineage, first described in the Republic of South Africa (RSA), and the B.1.1.7 lineage originally reported in the United Kingdom, and directly compare the replication kinetics of these two VOCs in Vero E6 cells. In this analysis, we also investigated a B.1.1.7 VOC (QLD1516/2021) carrying a 7-nucleotide deletion in the open reading frame 7a (ORF7a) gene, likely truncating and rendering the ORF7a protein of this virus defective. We demonstrate that the replication of the B.1.351 VOC (QLD1520/2020) in Vero E6 cells can be detected earlier than the B.1.1.7 VOCs (QLD1516/2021 and QLD1517/2021), before peaking at 48 h post infection (p.i.), with significantly higher levels of virus progeny. Whilst replication of the ORF7a defective isolate QLD1516/2021 was delayed longer than the other viruses, slightly more viral progeny was produced by the mutant compared to the unmutated isolate QLD1517/2021 at 72 h p.i. Collectively, these findings contribute to our understanding of SARS-CoV-2 replication and evolutionary dynamics, which have important implications in the development of future vaccination, antiviral therapies, and epidemiological control strategies for COVID-19.  相似文献   
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