3D printed high-precision porous scaffolds prepared by fused deposition modeling induce macrophage polarization to promote bone regeneration.

Macrophage-mediated bone immune responses significantly influence the repair of bone defects when utilizing tissue-engineered scaffolds. Notably, the scaffolds' physical structure critically impacts macrophage polarization. The optimal pore size for facilitating bone repair remains a topic of debate due to the imprecision of traditional methods in controlling scaffold pore dimensions and spatial architecture. In this investigation, we utilized fused deposition modeling (FDM) technology to fabricate high-precision porous polycaprolactone (PCL) scaffolds, aiming to elucidate the impact of pore size on macrophage polarization. We assessed the scaffolds' mechanical attributes and biocompatibility. Real-time quantitative reverse transcription polymerase chain reaction was used to detect the expression levels of macrophage-related genes, and enzyme linked immunosorbent assay for cytokine secretion levels.In vitroosteogenic capacity was determined through alkaline phosphatase and alizarin red staining. Our findings indicated that macroporous scaffolds enhanced macrophage adhesion and drove their differentiation towards the M2 phenotype. This led to the increased production of anti-inflammatory factors and a reduction in pro-inflammatory agents, highlighting the scaffolds' immunomodulatory capabilities. Moreover, conditioned media from macrophages cultured on these macroporous scaffolds bolstered the osteogenic differentiation of bone marrow mesenchymal stem cells, exhibiting superior osteogenic differentiation potential. Consequently, FDM-fabricated PCL scaffolds, with precision-controlled pore sizes, present promising prospects as superior materials for bone tissue engineering, leveraging the regulation of macrophage polarization.

Preparation and characterization of a biocompatible glucose-sensitive electrospun nanofibers scaffolds containing dexamethasone with enhanced osteogenic propertiesin vitrohigh glucose environment.

Diabetes has made it challenging to repair alveolar bone defects. A successful method for bone repair utilizes a glucose-sensitive osteogenic drug delivery. This study created a new glucose-sensitive nanofiber scaffold with controlled dexamethasone (DEX) release. DEX-loaded polycaprolactone/chitosan nanofibers scaffolds were created using electrospinning. The nanofibers had high porosity (>90%) and proper drug loading efficiency (85.51 ± 1.21%). Then, glucose oxidase (GOD) was immobilized on the obtained scaffolds by a natural biological cross-linking agent, genipin (GnP), after soaking in the mixture solution containing GOD and GnP. The enzyme properties and glucose sensitivity of the nanofibers were investigated. The results showed that GOD was immobilized on the nanofibers and exhibited good enzyme activity and stability. Meanwhile, the nanofibers expanded gradually in response to the increase in glucose concentration, followed by the release of DEX increased. The phenomena indicated that the nanofibers could sense glucose fluctuation and possess favorable glucose sensitivity. In addition, the GnP nanofibers group showed lower cytotoxicity in the biocompatibility test compared with a traditional chemical cross-linking agent. Lastly, the associated osteogenesis evaluation found that the scaffolds effectively promoted MC3T3-E1 cells' osteogenic differentiation in high-glucose environments. As a result, the glucose-sensitive nanofibers scaffolds offer a viable treatment option for people with diabetes with alveolar bone defects.

Multi-stage malaria parasite recognition by deep learning.

MOTIVATION: Malaria, a mosquito-borne infectious disease affecting humans and other animals, is widespread in tropical and subtropical regions. Microscopy is the most common method for diagnosing the malaria parasite from stained blood smear samples. However, this technique is time consuming and must be performed by a well-trained professional, yet it remains prone to errors. Distinguishing the multiple growth stages of parasites remains an especially challenging task. RESULTS: In this article, we develop a novel deep learning approach for the recognition of malaria parasites of various stages in blood smear images using a deep transfer graph convolutional network (DTGCN). To our knowledge, this is the first application of graph convolutional network (GCN) on multi-stage malaria parasite recognition in such images. The proposed DTGCN model is based on unsupervised learning by transferring knowledge learnt from source images that contain the discriminative morphology characteristics of multi-stage malaria parasites. This transferred information guarantees the effectiveness of the target parasite recognition. This approach first learns the identical representations from the source to establish topological correlations between source class groups and the unlabelled target samples. At this stage, the GCN is implemented to extract graph feature representations for multi-stage malaria parasite recognition. The proposed method showed higher accuracy and effectiveness in publicly available microscopic images of multi-stage malaria parasites compared to a wide range of state-of-the-art approaches. Furthermore, this method is also evaluated on a large-scale dataset of unseen malaria parasites and the Babesia dataset. AVAILABILITY: Code and dataset are available at https://github.com/senli2018/DTGCN_2021 under a MIT license.

2 kW narrow spectral width monolithic continuous wave in a near-diffraction-limited fiber laser.

We demonstrate a monolithic continuous wave (CW) fiber laser source at 1070 nm, producing 2 kW laser power with a very narrow spectral width (∼75 GHz) and near-diffraction-limited beam quality (M2<1.4). The laser consists of a CW fiber laser oscillator and two double cladding fiber amplifiers in the master oscillator-power amplifier configuration. The master oscillator is a distributed Bragg reflected fiber laser, producing ∼6 W laser power with ∼25 GHz spectral width. The two double cladding fiber amplifiers were developed to enhance the laser power up to ∼200 and ∼2050 W, respectively. The slope efficiency of the main amplifier reaches 84.8%. Under the full power output, the 3 dB spectral width and 20 dB spectral width of the laser emission spectrum was ∼75 GHz and 1.2 nm, respectively.

Incorporating Six Degree-of-Freedom Intervertebral Joint Stiffness in a Lumbar Spine Musculoskeletal Model-Method and Performance in Flexed Postures.

Intervertebral translations and rotations are likely dependent on intervertebral stiffness properties. The objective of this study was to incorporate realistic intervertebral stiffnesses in a musculoskeletal model of the lumbar spine using a novel force-dependent kinematics approach, and examine the effects on vertebral compressive loading and intervertebral motions. Predicted vertebral loading and intervertebral motions were compared to previously reported in vivo measurements. Intervertebral joint reaction forces and motions were strongly affected by flexion stiffness, as well as force-motion coupling of the intervertebral stiffness. Better understanding of intervertebral stiffness and force-motion coupling could improve musculoskeletal modeling, implant design, and surgical planning.

Benzopyranones from the endophytic fungus Hyalodendriella sp. Ponipodef12 and their bioactivities.

The endophytic fungus Hyalodendriella sp. Ponipodef12 was isolated from the hybrid 'Neva' of Populus deltoides Marsh × P. nigra L. In this study, four benzopyranones were isolated from the ethyl acetate extract of Hyalodendriella sp. Ponipodef12, and identified as palmariol B (1), 4-hydroxymellein (2), alternariol 9-methyl ether (3), and botrallin (4) by means of physicochemical and spectroscopic analysis. All the compounds were evaluated for their antibacterial, antifungal, antinematodal and acetylcholinesterase inhibitory activities. 4-Hydroxymellein (2) exhibited stronger antibacterial activity than the other compounds. Palmariol B (1) showed stronger antimicrobial, antinematodal and acetylcholinesterase inhibitory activities than alternariol 9-methyl ether (3) which indicated that the chlorine substitution at position 2 may contribute to its bioactivity. The results indicate the potential of this endophytic fungus as a source of bioactive benzopyranones.

Transjugular intrahepatic portosystemic shunt for portal vein thrombosis with symptomatic portal hypertension in liver cirrhosis.

BACKGROUND & AIMS: Data on the management of portal vein thrombosis (PVT) in patients with decompensated cirrhosis are extremely limited, particularly in the cases of the transjugular intrahepatic portosystemic shunt (TIPS). We assessed the outcome of TIPS for PVT in patients with cirrhosis and symptomatic portal hypertension and determined the predictors of technical success and survival. METHODS: In the retrospective study, 57 consecutive patients receiving TIPS were enrolled between December 2001 and September 2008. All were diagnosed with chronic PVT, and 30 had portal cavernoma. Indications for TIPS were variceal hemorrhage (n = 56) and refractory ascites (n = 1). RESULTS: TIPS were successfully placed in 75% of patients (43/57). The independent predictors of technical success included portal cavernoma, and the degree of thrombosis within the main portal vein (MPV), the portal vein branches, and the superior mesenteric vein. Only one patient died of severe procedure-related complication. The cumulative 1-year shunt dysfunction and hepatic encephalopathy rates were 21% and 25%, respectively. The cumulative 1- and 5-year variceal re-bleeding rates differed significantly between the TIPS success and failure groups (10% and 28% versus 43% and 100%, respectively; p = 0.0004), while the cumulative 1- and 5-year survival rates were similar between the two groups (86% and 77% versus 78% and 62%, respectively; p = 0.34). The independent predictor of survival in PVT patients with decompensated cirrhosis was the degree of MPV occlusion (hazard ratio 0.189, 95% CI 0.042-0.848). CONCLUSIONS: TIPS should be considered a safe and feasible alternative therapy for chronic PVT in selected patients with decompensated cirrhosis. Both technical success and survival were closely associated with the degree of MPV occlusion.

Antimicrobial activity of sphingolipids isolated from the stems of cucumber (Cucumis sativus L.).

Three antimicrobial sphingolipids were separated by bioassay-guided isolation from the chloroform fraction of the crude methanol extract of cucumber (Cucumis sativus L.) stems and identified as (2S,3S,4R,10E)-2-[(2'R)-2-hydroxytetra-cosanoylamino]-1,3,4-octadecanetriol-10-ene (1), 1-O-ß-D-glucopyranosyl(2S,3S,4R,10E)-2-[(2'R)-2-hydroxy-tetracosanoylamino]-1,3,4-octadecanetriol-10-ene (2) and soya-cerebroside I (3) by their physicochemical properties and spectroscopic analysis. They were evaluated to show antifungal and antibacterial activity on test microorganisms including four fungal and three bacterial species. Among them, compound 1, a relatively low polarity aglycone,  exhibited stronger antimicrobial activity than its corresponding glycoside 2. The results indicated that sphingolipids could be the main antimicrobial compounds in the crude methanol extract of cucumber stems.

[Transjugular intrahepatic portosystemic shunt and combination with percutaneous transhepatic or transsplenic approach for the treatment of portal vein thrombosis with or without cavernomatous transformation].

OBJECTIVE: To evaluate retrospectively the feasibility, efficacy and safety of transjugular intrahepatic portosystemic shunt (TIPS) or percutaneous transhepatic or transsplenic approach to the portal vein with the combination of TIPS for the treatment of patients with portal vein thrombosis with or without cavernous transformation. METHODS: Sixty-five patients with portal vein thrombosis from July 2002 to August 2007 at our hospital were analyzed retrospectively. Indirect portography through superior mesenteric artery was performed to determine the approaches for TIPS procedure. If the intrahepatic portal vein branches were visualized, TIPS was implemented directly from transjugular approach; if the intrahepatic portal vein branches failed to be visualized, an ultrasound-guided percutaneous transhepatic or transsplenic approach was performed to recanalize the thrombosed portal vein initially followed by TIPS placement to reconstruct the portal venous flow. Efficacy and complications were observed and revision and survival rates monitored during the follow-up. RESULTS: TIPS were successfully created in 54 of 65 patients with portal vein thrombosis with a success rate of 83.1%. Among them, TIPS were performed directly in 36 of 40 patients; portal vein recanalization were successfully performed via transhepatic access in 15 of 25 patients, and 3 of remaining 5 who failed the transhepatic approach were successfully done from transsplenic access. Then TIPS placement was accomplished with a success rate of 72.0% (18/25). The success rate in cirrhotic patients was 82.4% (42/51) and it was not significant different from those without cirrhosis 85.7% (12/14) (P = 0.766). While the success rate in the patients with cavernous transformation 71.8% (28/39) showed a significant difference compared to that without cavernous transformation 100% (26/26) (P = 0.002). The success rates in portal vein thrombosis and cavernous transformation with or without cirrhosis were 42.9% (18/42) and 83.3% (10/12) respectively, exhibiting a significant difference (P = 0.021). The mortality rate of 30 days post-operation was 3.7% (2/54). From Day 1 to 63 months follow-up, The incidence rate of hepatic encephalopathy was 27.8% (15/54); revision rate 22.2% (12/54); median survival time 31.4 months. CONCLUSIONS: Conventional TIPS or percutaneous transhepatic or transsplenic approach combined with TIPS for the treatment of portal vein thrombosis with or without cavernous transformation are feasible, safe and effective. It is essential to recanalize the thrombosed portal vein initially followed by TIPS placement to reconstruct the portal venous flow.