717 research outputs found
Lattice-patterned collagen fibers and their dynamics in axolotl skin regeneration
The morphology of collagen-producing cells and the structure of produced collagen in the dermis have not been well-described. This lack of insights has been a serious obstacle in the evaluation of skin regeneration. We succeeded in visualizing collagen-producing cells and produced collagen using the axolotl skin, which is highly transparent. The visualized dermal collagen had a lattice-like structure. The collagen-producing fibroblasts consistently possessed the lattice-patterned filopodia along with the lattice-patterned collagen network. The dynamics of this lattice-like structure were also verified in the skin regeneration process of axolotls, and it was found that the correct lattice-like structure was not reorganized after simple skin wounding but was reorganized in the presence of nerves. These findings are not only fundamental insights in dermatology but also valuable insights into the mechanism of skin regeneration
Recurrence of angina pectoris after percutaneous coronary intervention is reduced by statins in Japanese patients
SummaryBackgroundStatins have been reported to reduce cardiovascular events in patients with coronary artery disease (CAD). Percutaneous coronary intervention (PCI) is commonly used to relieve ischemic symptoms in patients with CAD. However, there is little information on the effect of statins on cardiovascular events after PCI, even in the era of coronary stent implantation.MethodsA total of 1019 patients with acute or chronic CAD and modest total cholesterol levels (180–240mg/dl) were enrolled and randomly assigned to treatment with or without statins. We evaluated the effect of any available statin on the incidence of cardiovascular events after PCI. The primary endpoint was a composite of cardiovascular death, nonfatal acute myocardial infarction (MI), recurrent angina pectoris requiring emergency rehospitalization (rAP), heart failure, and stroke.ResultsIndications for PCI were stable angina in 54%, ST-elevation MI in 41% and non-ST-elevation MI/unstable angina pectoris in 5%. After 2 years of statin treatment, low-density lipoprotein cholesterol (LDL-C) decreased from 133 to 96mg/dl. Stents were implanted in 84% of all cases. The primary endpoint event rate was 9.5% in the statin group and 14.7% in the non-statin group (p=0.0292). Of all primary endpoint events, only rAP was significantly suppressed by statins (p=0.0027). In rAP patients, coronary angiography revealed that statins suppressed restenosis but not new lesions.ConclusionsFor Japanese CAD patients treated with PCI and stent implantation, statin therapy reduced the incidence of recurrent cardiovascular events, particularly rAP. Discretionary statin treatment to achieve LDL-C levels <100mg/dl effectively reduced restenosis causing rAP
Gas-Phase Epoxidation of Propylene to Propylene Oxide on a Supported Catalyst Modified with Various Dopants
In the present study, the production of propylene oxide (PO) from propylene via gas-phase epoxidation was investigated using various catalysts. Although Ag is known to be a highly active catalyst for the epoxidation of ethylene, it was not active in the present reaction. Both Al and Ti showed high levels of activity, however, which resulted in confusion. The present study was conducted to solve such confusion. Although the employment of MCM-41 modified with Ti and/or Al was reported as an active catalyst for epoxidation, the combination resulted in the formation of PO at a less than 0.1% yield. Since this research revealed that the acidic catalyst seemed favorable for the formation of PO, versions of ZSM-5 that were both undoped and doped with Na, Ti, and Ag were used as catalysts. In these cases, small improvements of 0.67% and 0.57% were achieved in the PO yield on H‒ZSM-5 and Ti‒ZSM-5, respectively. Based on the results of the Ti-dopant and acidic catalysts, Ag metal doped on carbonate species with a smaller surface area was used as a catalyst. As reported, Ag‒Na/CaCO3 showed a greater yield of PO at 1.29%. Furthermore, the use of SrCO3 for CaCO3 resulted in a further improvement in the PO yield to 2.17%. An experiment using CO2 and NH3 pulse together with SEM and TEM examinations for Ag‒Na/CaCO3 revealed that the greatest activity was the result of the greater particle size of metallic Ag rather than the acid‒base properties of the catalysts
PLOD2 is essential to functional activation of integrin β1 for invasion/metastasis in head and neck squamous cell carcinomas.
Identifying the specific functional regulator of integrin family molecules in cancer cells is critical because they are directly involved in tumor invasion and metastasis. Here we report high expression of PLOD2 in oropharyngeal squamous cell carcinomas (SCCs) and its critical role as a stabilizer of integrin β1, enabling integrin β1 to initiate tumor invasion/metastasis. Integrin β1 stabilized by PLOD2-mediated hydroxylation was recruited to the plasma membrane, its functional site, and accelerated tumor cell motility, leading to tumor metastasis in vivo, whereas loss of PLOD2 expression abrogated it. In accordance with molecular analysis, examination of oropharyngeal SCC tissues from patients corroborated PLOD2 expression associated with integrin β1 at the invasive front of tumor nests. PLOD2 is thus implicated as the key regulator of integrin β1 that prominently regulates tumor invasion and metastasis, and it provides important clues engendering novel therapeutics for these intractable cancers
Clinical utility of silk-elastin sponge in patients with chronic and acute skin ulcers: study protocol of a multi-center clinical trial
INTRODUCTION: Not only chronic but also some acute wounds have a risk of infection and become unhealed wounds. Silk-elastin sponge has been developed to treat chronic wounds that are susceptible to infection. Preclinical and clinical studies suggested that silk-elastin sponge is safe for humans and can promote granulation tissue formation by reducing bacterial growth in chronic wounds. The central aim of this trial is to evaluate the clinical utility and safety of silk-elastin sponge for the treatment of chronic and acute skin ulcers. METHODS: This study is a prospective, multicenter, single-arm, uncontrolled clinical trial. In this study, 20 patients with chronic ulcers and five with an acute one will be included; patients with wound infection will be excluded. Silk-elastin sponges are applied and covered with a dressing for 14 days. PLANNED OUTCOMES: The primary endpoint is the frequency of patients with chronic wounds in whom the investigator confirms the formation of a healthy wound bed at 14 days after the initial application of the study device. In addition, safety for acute wounds and handiness of the study device will be assessed. TRIAL REGISTRATION NUMBER: jRCT2052210072
Cultured epithelial autografts for the treatment of large-to-giant congenital melanocytic nevus in 31 patients
Introduction: Giant congenital melanocytic nevus (GCMN) is a large melanocytic nevus, and its full-thickness removal is usually difficult due to the lack of skin available for reconstruction. Curettage is an alternative approach in cases of GCMN to remove the superficial dermis above the cleavage plane with a curette in the neonatal period, and its major complications include repigmentation, retarded epithelization, and hypertrophic scar formation. In Japan, the JACE® cultured epidermal autograft (CEA) was approved and covered by public healthcare insurance for the treatment of congenital melanocytic nevus (CMN) that is difficult to treat with conventional methods in 2016. We have used CEA for wounds after curettage in the neonatal period or following ablation after the neonatal period in combination with laser therapies to reduce the above-mentioned complications. Methods: In this study, we summarized all consecutive CMN patients treated using CEA from December 2016 to April 2019 and evaluated the duration required for epithelialization, incidence of hypertrophic scar, and color change in the target nevus by comparing the L∗ values one year later between the Curettage group, the non-Curettage group with initial treatment or the subsequent group. Results: No significant differences were seen in the epithelization period or incidence of hypertrophic scars among the groups, but the color of the target nevus was improved significantly in the Curettage group (p < 0.01) and non-Curettage group with initial treatment (p < 0.01). Conclusions: In conclusion, CEA seems to accelerate epithelization after curettage or ablation of CMN, and this treatment could improve the color of CMN when applied initially
Microstructure, Mechanical Properties and Fracture Behavior of α Particle Irradiated Type 316 Stainless Steel
The present work is a research of the effect of helium on the microstructure, mechanical properties and fracture behaviors of a type 316 austenitic steel. Helium implantation was performed by 30-MeV α-particle injection on very small size specimens, using a cyclotron. Average helium content in a He-deposited region was up to 2000 appm He. In the case of 2000appm He implantation, intergranular fracture was sometimes observed on the helium deposited region after tensile test at room temperature. At elevated temperature test, however, this material showed the transition of fracture mode from transgranular-ductile fracture at 773K to intergranular fracture at 873. In the case of 500 appm He implantation, the transition of fracture mode was recognized at a temperature range of 873K to 973K
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