37 research outputs found
Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)
In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field
Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study
Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised
The complete chloroplast genome of Grewia biloba var. parviflora (Bunge) Hand.-Mazz. (Malvaceae)
Grewia biloba var. parviflora (Bunge) Hand.-Mazz. (1933), a shrub or small tree, is native to northern and southern China. It is an excellent relief and medicinal plant. The complete chloroplast genome is 158,043 bp in length, with a large single-copy region of 86,957 bp, a small single-copy region of 20,138 bp, two inverted repeat regions of 25,474 bp each, and a GC content of 37.4%. There were 129 genes annotated, including 84 known protein-coding genes, 37 tRNAs, and eight rRNAs. The phylogenetic trees are constructed using plastome data from 38 species and the maximum-likelihood method. The results of the chloroplast genome-wide analysis and the phylogenetic tree show the taxonomic phylogeny of the G. biloba var. parviflora in relation to other species, increasing the accuracy of the phylogenetic classification of the plant
Nanocrystalline Hydroxyapatite-Based Scaffold Adsorbs and Gives Sustained Release of Osteoinductive Growth Factor and Facilitates Bone Regeneration in Mice Ectopic Model
Nanocrystalline hydroxyapatite (NHA) is a biocompatible, biodegradable, and osteoconductive bone graft material; however, it lacks osteoinductivity. The present study is aimed at investigating the feasibility of nanocrystalline hydroxyapatite (NHA) as an osteoinductive growth factor carrier. Bone morphogenic protein 2 (BMP2), an osteoinductive growth factor, was incorporated into NHA (BMP2-NHA) using a simple adsorption method. The growth factor loading and release kinetics were profiled using fluorescein-isothiocyanate-labeled bovine serum albumin (FITC-BSA) as a mimic of the osteoinductive growth factor BMP2. The effect of BMP2-NHA on the osteogenic differentiation of C2C12 cells and ectopic bone formation in mice were tested. Confocal laser-scanning microscopy showed that FITC-BSA was diffused throughout the porous structure of NHA. FITC-BSA was efficiently loaded in NHA and sustained release was observed up to 35 days in vitro. BMP2-NHA enhanced the expression of osteogenic markers Runx2, Osterix, Alp, and Col1α1 and ALP activity in C2C12 cells compared to NHA. Similarly, μ-CT and histological examinations showed that BMP2-NHA robustly induced ectopic bone formation in mice. This study suggests that NHA could be used as an effective carrier of osteoinductive growth factors, which ensures osteoinductivity of NHA via sustained release of the growth factor
In Situ Observation of Domain Wall Pinning in Sm(Co,Fe,Cu,Zr)(z) Magnet by Lorentz Microscopy
The microstructure and magnetic domain-wall motion of a sintered Sm(Co,Fe,Cu,Zr)(z) permanent magnet with different Cu and Fe contents was investigated by Lorentz transmission electron microscopy. The domain-wall motion under different magnetic fields indicates that most domain walls are strongly attracted by the SmCo5 boundary phases, but some of them are repulsed to the Sm2Co17 cell phase. Differences in Cu and Fe distribution at the SmCo5 cell boundary phase and the SmCo5/Sm2Co17 interface are considered to result in domain-wall behavior, and a larger Cu and a smaller Fe content in the sample make the attractive pinning force stronger and, therefore, coercivity is higher
Cardioprotective Effects of Genistin in Rat Myocardial Ischemia-Reperfusion Injury Studies by Regulation of P2X7/NF-κB Pathway
The present study aimed to assess the effects and mechanisms of genistin in the rat model of myocardial ischemia reperfusion injury. The rat hearts were exposed to the left anterior descending coronary artery (LAD) ligation for 30 min followed by 1 h of reperfusion. In the rat of myocardial ischemia/reperfusion (MI/R), it was found that genistin pretreatment reduced myocardial infarct size, improved the heart rate, and decreased creatine kinase (CK) and lactate dehydrogenase (LDH) levels in coronary flow. This pretreatment also increased catalase (CAT), superoxide dismutase (SOD) activities but decreased glutathione (GSH), malondialdehyde (MDA) levels. Furthermore, we determined that genistin can ameliorate the impaired mitochondrial morphology and oxidation system; interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-10 (IL-10), and tumor necrosis factor-α (TNF-α) levels were also recovered. Besides, related-proteins of nuclear factor kappa-B (NF-κB) signal pathway activated by P2X7 were investigated to determine the molecular mechanism of genistin and their expressions were measured by western blot. These results presented here demonstrated that genistin enhanced the protective effect on the rats with myocardial ischemia reperfusion injury. Therefore, the cardioprotective effects of genistin may rely on its antioxidant and anti-inflammatory activities via suppression of P2X7/NF-κB pathways
Fluid–solid coupling numerical simulation for the performance prediction and valve dynamic analysis of a rotary compressor
Chitinase 3-like 1-CD44 interaction promotes metastasis and epithelial-to-mesenchymal transition through β-catenin/Erk/Akt signaling in gastric cancer
Abstract Background Enzymatically inactive chitinase-like protein CHI3L1 drives inflammatory response and promotes tumor progression. However, its role in gastric cancer (GC) tumorigenesis and metastasis has not yet been fully elucidated. We determined the significance of CHI3L1 expression in patients with GC. We also explored an as-yet unknown receptor of CHI3L1 and investigated the involved signaling in GC metastasis. Methods CHI3L1 expression was evaluated by immunoblotting, tissue microarray-based immunohistochemistry analysis (n = 100), and enzyme linked immunosorbent assay (ELISA) (n = 150). The interactions between CD44 and CHI3L1 or Interleukin-13 receptor alpha 2 (IL-13Rα2) were analyzed by co-immunoprecipitation, immunofluorescence co-localization assay, ELISA, and bio-layer interferometry. The roles of CHI3L1/CD44 axis in GC metastasis were investigated in GC cell lines and experimental animal model by gain and loss of function. Results CHI3L1 upregulation occurred during GC development, and positively correlated with GC invasion depth, lymph node status, and tumor staging. Mechanically, CHI3L1 binding to CD44 activated Erk and Akt, along with β-catenin signaling by phosphorylating β-catenin at Ser552 and Ser675. CD44 also interacted with IL-13Rα2 to form a complex. Notably, CD44v3 peptide and protein, but not CD44v6 peptide or CD44s protein, bound to both CHI3L1 and IL-13Rα2. Our in vivo and in vitro data further demonstrated that CHI3L1 promoted GC cell proliferation, migration, and metastasis. Conclusions CHI3L1 binding to CD44v3 activates Erk, Akt, and β-catenin signaling, therefore enhances GC metastasis. CHI3L1 expression is a novel biomarker for the prognosis of GC, and these findings have thus identified CHI3L1/CD44 axis as a vital pathway and potential therapeutic target in GC
Prefabricated 3D-printed tissue-engineered bone for mandibular reconstruction: A preclinical translational study in primate
The advent of three dimensionally (3D) printed customized bone grafts using different biomaterials has enabled repairs of complex bone defects in various in vivo models. However, studies related to their clinical translations are truly limited. Herein, 3D printed poly(lactic-co-glycolic acid)/β-tricalcium phosphate (PLGA/TCP) and TCP scaffolds with or without recombinant bone morphogenetic protein −2 (rhBMP-2) coating were utilized to repair primate’s large-volume mandibular defects and compared efficacy of prefabricated tissue-engineered bone (PTEB) over direct implantation (without prefabrication). 18F-FDG PET/CT was explored for real-time monitoring of bone regeneration and vascularization. After 3-month’s prefabrication, the original 3D-architecture of the PLGA/TCP-BMP scaffold was found to be completely lost, while it was properly maintained in TCP-BMP scaffolds. Besides, there was a remarkable decrease in the PLGA/TCP-BMP scaffold density and increase in TCP-BMP scaffolds density during ectopic (within latissimus dorsi muscle) and orthotopic (within mandibular defect) implantation, indicating regular bone formation with TCP-BMP scaffolds. Notably, PTEB based on TCP-BMP scaffold was successfully fabricated with pronounced effects on bone regeneration and vascularization based on radiographic, 18F-FDG PET/CT, and histological evaluation, suggesting a promising approach toward clinical translation.This work was supported by the National Natural Science Foundation of China [Grant No. 81671029], the National Major Science and Technology Project of China [Grant No. 2016YFC1102900], the Guangzhou Science, Technology and Innovation Commission [Grant Nos. 201803040008 and 201704030024], the International Team for Implantology [Grant No. 881_2012], the Bureau of Education of Guangzhou Municipality [Grant No. 1201610458], China Scholarship Council (No. 201908440308), Spanish Ministry of Science, Innovation and Universities [Grant No. RTI2018-095566–B-I00], and Junta de Extremadura [Grant No. IB16094]; the last two cofinanced with European Regional Development Funds.peerReviewe