4D printing has a great potential for the manufacturing of soft robotics and medical devices. The alliance of digital light processing (DLP) 3D printing and novel shape-memory photopolymers allows ...for the fabrication of smart 4D-printed medical devices in high resolution and with tailorable functionalities. However, most of the reported 4D-printed materials are nondegradable, which limits their clinical applications. On the other hand, 4D printing of biodegradable shape-memory elastomers is highly challenging, especially when transition points close to physiological temperature and shape fixation under ambient conditions are required. Here, we report the 4D printing of biodegradable shape-memory elastomers with tailorable transition points covering physiological temperature, by using poly(D,L-lactide-co-trimethylene carbonate) methacrylates at various monomer feed ratios. After the programming step, the high-resolution DLP printed stents preserved their folded shape at room temperature, and showed efficient shape recovery at 37 °C. The materials were cytocompatible and readily degradable under physiological conditions. Furthermore, drug-loaded devices with tuneable release kinetics were realized by DLP-printing with resins containing polymers and levofloxacin or nintedanib. This study offers a new perspective for the development of next-generation 4D-printed medical devices.
Digital light 4D printing of biodegradable drug-eluting elastomeric devices with tailorable thermal response at the physiological temperature and tunable drug release. Display omitted
•Biodegradable shape-memory elastomers were DLP printed.•The materials displayed elasticity below and above their transition temperatures.•4D printed elastomeric stents showed efficient shape recovery at 37 °C.•4D printed drug-loaded devices showed tuneable release kinetics.
In this study, we identified a pancreatic lipase‐related protein 2 (PLRP2) gene through searching the transcriptome data of the brown planthopper, Nilaparvata lugens, a monophagous rice pest. PLRP2 ...mRNAs were first isolated in the human pancreas and play an important role in hydrolysis of galactolipids from the diet. Although homologous PLRP2 genes have been identified in many insect species, their physiological functions remain unknown. The present study for the first time reports the functional role of PLRP2 in an insect species. Differing from mammal PLRP2s, N. lugens PLRP2 was highly expressed in developing oocytes of the ovaries of female adults and little expressed in laid eggs. Suppression of N. lugens PLRP2 expression using RNA interference significantly inhibited egg hatching in rice seedlings, implying that N. lugens PLRP2 was important for oocyte maturation and development. This novel finding will improve our understanding of the reproductive strategies in insects and provides a potential target for future management of crop pests.
Hypocalcemia following thyroidectomy is a common and potentially life‐threatening complication. It is caused by intraoperative injury to the parathyroid glands or their blood supply. Although several ...studies have shown that patients with a prior history of bariatric surgery may be at an increased risk for hypocalcemia after thyroidectomy, no clear recommendations exist for preventing and managing this condition in this population. This paper highlights the significance of understanding this risk and of obtaining a history of prior bariatric surgery before thyroidectomy. We propose concise recommendations for preventing and managing hypocalcemia following thyroidectomy in patients with a history of bariatric surgery.
A scarlet fever outbreak occurred in Hong Kong in 2011. The majority of cases resulted in the isolation of Streptococcus pyogenes emm12 with multiple antibiotic resistances. Phylogenetic analysis of ...22 emm12 scarlet fever outbreak isolates, 7 temporally and geographically matched emm12 non-scarlet fever isolates, and 18 emm12 strains isolated during 2005-2010 indicated the outbreak was multiclonal. Genome sequencing of 2 nonclonal scarlet fever isolates (HKU16 and HKU30), coupled with diagnostic polymerase chain reaction assays, identified 2 mobile genetic elements distributed across the major lineages: a 64.9-kb integrative and conjugative element encoding tetracycline and macrolide resistance and a 46.4-kb prophage encoding superantigens SSA and SpeC and the DNase Spd1. Phenotypic comparison of HKU16 and HKU30 with the S. pyogenes M1T1 strain 5448 revealed that HKU16 displays increased adherence to HEp-2 human epithelial cells, whereas HKU16, HKU30, and 5448 exhibit equivalent resistance to neutrophils and virulence in a humanized plasminogen murine model. However, in contrast to M1T1, the virulence of HKU16 and HKU30 was not associated with covRS mutation. The multiclonal nature of the emm12 scarlet fever isolates suggests that factors such as mobile genetic elements, environmental factors, and host immune status may have contributed to the 2011 scarlet fever outbreak.
To determine the HIV and hepatitis C virus (HCV) geographical distribution among drug users in China, a systematic literature review of 40 peer-reviewed publications (comprising 15,565 drug users) ...was conducted. Of the total drug users, 10,724 were found to be injection drug users (IDUs) and 4841 were non-injection drug users (non-IDUs). Various studies identified that among IDUs and non-IDUs, the overall HIV prevalence rates were 12.55% and 1.05%, and the HCV prevalence rates were 66.97% and 18.30%, respectively. The HIV prevalence rate ranged from 0% (Anhui and Inner Mongolia) to 52.51% (Yunnan) among IDUs, and from 0% to 19.80% among non-IDUs correspondingly. The HCV prevalence rate ranged from 11.43% (Shannxi) to 90.77% (Hubei) among IDUs, and from 0% (Anhui) to 40.00% (Fujian) among non-IDUs. Based on the high prevalence of HIV and HCV among drug users, scaling-up harm reduction was required from 'heroin trafficking areas' to other areas in China.
Alginate oligosaccharides (AOS), belonging to the class of functional marine oligosaccharides, are low-molecular polymers linked by β-1,4-mannuronic acid (M) and α-1,4-guluronic acid (G), which could ...be classically obtained by enzymatic hydrolysis of alginate. With low viscosity and good water solubility, as well as anti-oxidant, immune regulation, anti-bacterial and anti-inflammatory activities, AOS have been widely used in medical science and functional food, green agriculture and other fields. As new bio-feed additives, AOS have broad potential applications in animal husbandry. In this review, the sources of alginate, chemical structure and preparation methods of AOS, and their biological activities and application in livestock and poultry are summarized. We expect this review could contribute to lay a foundation of application and further research for AOS in livestock and poultry.
Summary
Our study focused on the associations of metabolites with BMD and osteoporosis, finding that several metabolites are associated with BMD, and metabolites combined with bone turnover markers ...tend to be more sensitive in distinguishing osteoporosis in both males and postmenopausal females, which might be meaningful for the early diagnosis of osteoporosis.
Introduction
Our study aimed to evaluate the association of metabolites with bone, trying to find new metabolic markers that are distinguishing for low bone mineral density (BMD).
Methods
Our study recruited 320 participants, including 138 males and 182 postmenopausal females from the Shanghai area. Bone turnover markers (BTMs), including osteocalcin, PINP and β-CTX, and other biochemical traits were tested. BMD values of the lumber spine (L1–4), femoral neck and total hip were determined using dual-energy X-ray absorptiometry and the serum metabolome profiles including 221 metabolites from five groups (acylcarnitines, amino acids, biogenic amines, glycerophospholipids, sphingolipids and hexose) were assessed by mass spectrometry.
Results
No visual separation in the metabolic profiles between different BMD groups was observed in principal component analysis (PCA) or partial least squares discriminant analysis (PLS-DA) models. We compared metabolites in three groups with different BMD levels in males and postmenopausal females separately and further filtering these metabolites via random forest-based feature selection, a commonly applied machine learning algorithm which could select the features with the greatest impact on osteoporosis, then metabolites with the highest importance (≥ 5%) (5 in males and 9 in postmenopausal females) were selected to construct better models for osteoporosis classification. After adding these selected metabolites to the model, the area under the curve (AUC) of receiver operating characteristic (ROC) curves increased significantly (BTMs: AUC 0.729, 95% CI 0.647–0.802,
p
< 0.0001, model 1: AUC = 0.828, 95% CI 0.754–0.888,
p
< 0.0001; model 1 versus model of BTMs:
p
= 0.0158) compared to the AUC of the BTM-only model in males. Similar results were also observed in postmenopausal females (BTMs: AUC = 0.638, 95% CI 0.562–0.708,
p
= 0.0025; model 2: AUC = 0.741, 95% CI 0.669–0.803,
p
< 0.0001; model 1 versus model of BTMs:
p
= 0.0182).
Conclusion
Metabolites combined with traditional BTMs tend to better markers for distinguishing osteoporosis in both males and postmenopausal females than BTMs alone.
The stress triaxiality is, besides the strain intensity, the most important factor that controls initiation of ductile fracture. In this study, a series of tests including upsetting tests, shear ...tests and tensile tests on 2024-T351 aluminum alloy providing clues to fracture ductility for a wide range of stress triaxiality was carried out. Numerical simulations of each test was performed using commercial finite element code ABAQUS. Good correlation of experiments and numerical simulations was achieved. Based on the experimental and numerical results, the relation between the equivalent strain to fracture versus the stress triaxiality was quantified and it was shown that there are three distinct branches of this function with possible slope discontinuities in the transition regime. For negative stress triaxialities, fracture is governed by shear mode. For large triaxialities void growth is the dominant failure mode, while at low stress triaxialities between above two regimes, fracture may develop as a combination of shear and void growth modes.
The mammalian Hippo pathway is composed of mammalian Ste20-like (MST) kinases and large tumour suppressor (LATS) kinases. Upon the activation of the pathway, MST kinases phosphorylate and activate ...LATS kinases, which in turn phosphorylate transcriptional co-activators, yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ), recruit them to the cytosol from the nucleus and turn off cell cycle-promoting and anti-apoptotic gene transcriptions. Thus, the pathway restricts cell overgrowth and prevents tumourigenesis. Although a high cell density and stress signallings are known to activate the pathway, no specific stimulators are so far reported. As the dysfunction of the pathway is frequent in human cancers and correlates with poor prognosis, it is important to find out reagents that stimulate the pathway for not only basic research but also clinical medicine. We here developed a cell-based method of screening reagents that induce the recruitment of YAP to the cytosol. Using this method, we found that dobutamine inhibits the YAP-dependent gene transcription. Contrary to our expectations, the effect of dobutamine is independent of the Hippo pathway but our method opens the possibility to discover Hippo pathway stimulators or Hippo-independent YAP inhibitors.
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