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Enzyme immobilization using inorganic materials has been shown to preserve enzyme activity improving and improve their practical applications in biocatalytic process designs. Proper immobilization methods have been used to obtain high recycling and storage stability. In this study, we compared the activity and stability of in situ or crosslink-immobilized enzymes in a CaCO 3 biomineral carrier. More than 30% of the initial enzyme activity was preserved for both the systems after 180 days upon 15 activity measurements at room temperature, confirming the improved stability of these enzyme systems (100 mM phosphate buffer, pH 8.0); however, differences in enzyme loading, activity, and characteristics were observed for each of these methods. Each system exhibited efficacy of 80% and 20%, respectively. Based on the same amount of immobilized enzyme (0.2 mg), the specific activities of hydrolysis of p-nitrophenyl butyrate substrate at room temperature of in situ immobilized carboxyl esterase (CE) and crosslinked CE were 11.37 and 7.63 mM min -1  mg -1 , respectively (100 mM phosphate buffer, pH 8.0). Moreover, based on the kinetic behavior, in situ immobilized CE exhibited improved catalytic efficiency (Vmax Km -1 ) of the enzyme, exhibiting 4-fold higher activity and efficiency values than those of the CE immobilized in CaCO 3 . This is the first study to describe the stabilization of enzymes in CaCO 3 and compare the enzyme kinetics and efficiencies between in situ immobilization and crosslinking in CaCO 3 carriers., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2018. Published by Elsevier B.V.)

It is a challenge to assess metabolic dysregulation in fatty liver of human patients prior to clinical manifestations. Here, we recruited obese, but otherwise healthy, subjects to examine biochemical processes in the liver with simple triglyceride accumulation using stable isotopes and NMR analysis of metabolic products in blood. Intrahepatic triglycerides were measured using 1 H magnetic resonance spectroscopy, and volunteers received 2 H 2 O and [U- 13 C 3 ]glycerol orally, followed by a series of blood draws. NMR analysis of plasma triglycerides and glucose provided detailed information about metabolic pathways in patients with simple hepatic steatosis. Compared with subjects with low hepatic fat, patients with hepatic steatosis were characterized by the following: lower 13 C enrichments in the glycerol backbones of triglycerides (i.e., TG-[ 13 C]glycerol), higher [U- 13 C 3 ]glycerol metabolism through the tricarboxylic acid (TCA) cycle, delayed gluconeogenesis from [U- 13 C 3 ]glycerol, and less flexibility in adjusting supporting fluxes of glucose production upon an oral load of glycerol. In summary, simple hepatic steatosis was associated with enhanced [U- 13 C 3 ]glycerol metabolism through pathways that intersect the TCA cycle and delayed gluconeogenesis from glycerol.

Objective: To evaluate the efficacy of biocomposite screws used in ovariectomy (OVX)-induced osteoporotic rats., Methods: Twenty-four female Wistar rats (250-300 g, 12 weeks old) were divided into 4 groups: sham group (control), OVX-induced osteoporosis group (OVX), OVX and biodegradable poly(lactic-co-glycolic acid) (PLGA) without tricalcium phosphate (β-TCP) screw insertion group (OVX/BSR), and OVX and biocomposite (PLGA with β-TCP) screw insertion group (OVX/CSR). Three groups underwent bilateral OVX, and of these, 2 groups had 2 different types of screw inserted at the proximal tibia. At 25 weeks after OVX, the bilateral tibias were extracted. The extracted tibiae were scanned by ex vivo micro-computed tomography (CT) and stained with hematoxylin and eosin (H&E) and with Masson's trichrome stain for pathological assessment., Results: Compared with the ovariectomized groups, the control group had the highest values for bone mineral density (BMD), bone volume (BV)/total volume (TV), and trabecular number (Tb.N) and the lowest values for trabecular thickness (Tb.Th) and trabecular separation (Tb.Sp). In the pairwise comparison among ovariectomized groups, the OVX/CSR group had significantly higher BMD, BV/TV, and Tb.N values than the other 2 groups (OVX and OVX/BSR) and significantly lower Tb.Sp. Micro-CT scans showed clear evidence of new trabecular formation near the screw insertion site in the OVX/CSR group only. Analyses of H&E- and Masson's trichrome-stained sections showed more and thicker trabecular bone around the implant in the OVX/CSR group compared with the OVX and OVX/BSR groups., Conclusions: Biocomposite screws can improve local bone quality and facilitate osteoconductivity in an osteoporotic rat model., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Infectious aortitis is a rare disease in the antibiotic era. Only a small number of cases of nonaneurysmal infectious aortitis are discussed in literature, and its true incidence and natural history are not well defined. We present here a case of typical nonaneurysmal infectious aortitis with literature review of 19 cases of aortic infection in which the aorta is initially normal in caliber., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: No study has reported an animal-based experimental model of electrical injury to the spinal cord. This paper presents the first systematic establishment of an animal model of electrical injury to the spinal cord with subsequent pathophysiologic analysis., Method: The voltage required for the electrical shock was generated by an electroconvulsive therapy apparatus (57800 ECT unit; UGO BASILE, Italy). We used one side ear as the entry site and the contralateral hind limb as the exit site. Seven electrical shock (frequency, 120 Hz; pulse width, 0.9 ms; duration, 3 s; current, 99 mA) was applied to each rat and used rat showing hind limb weakness. Radiologic and histologic evaluations were performed at one day, one, two and four weeks after injury., Results: Twelve rats showed the hind limb weakness among the total 18 rats. Manganese-enhanced magnetic resonance imaging showed interruption of spinal cord enhancement in the thoracic area. Histological examination showed a greater decrease in the number of neurons in the ventral horn versus the dorsal horn., Conclusion: This study demonstrates a novel design and analysis of an animal-based experimental model of spinal cord injury by electrical etiology. This model is useful for experimental studies of injuries to the spinal cord., (Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.)

In this paper, a single-step room-temperature biosynthetic route for producing gold nanostructures using pear fruit is reported. The alkaline conditions of the pear fruit extract induced gold nanoparticles with plate-like morphologies. Successfully biosynthesized triangular and hexagonal nanoplates were observed, elegantly assembled with hexagonal gold nanoparticles. Nanostructure size, crystal nature, purity and morphologies were characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoemission spectroscopy (XPS) and energy dispersive X-ray analysis (EDAX). The edge lengths of the nanostructures ranged from 200 to 500 nm. Using AFM analysis, the nanohexagons were observed to have a thickness ranging from 12 to 20 nm. The XRD patterns showed a (1 1 1) preferential orientation of the nanostructures. The XPS and EDAX analysis also confirmed the presence of pure-phase Au without any substantial impurities. The preparation of nanostructured gold particles using pear fruit provides an environmentally friendly option, as compared to currently available chemical and/or physical methods.

A triple-tracer method was developed to provide absolute fluxes contributing to endogenous glucose production and hepatic tricarboxylic acid (TCA) cycle fluxes in 24-h-fasted rats by (2)H and (13)C nuclear magnetic resonance (NMR) analysis of a single glucose derivative. A primed, intravenous [3,4-(13)C(2)]glucose infusion was used to measure endogenous glucose production; intraperitoneal (2)H(2)O (to enrich total body water) was used to quantify sources of glucose (TCA cycle, glycerol, and glycogen), and intraperitoneal [U-(13)C(3)] propionate was used to quantify hepatic anaplerosis, pyruvate cycling, and TCA cycle flux. Plasma glucose was converted to monoacetone glucose (MAG), and a single (2)H and (13)C NMR spectrum of MAG provided the following metabolic data (all in units of micromol/kg/min; n = 6): endogenous glucose production (40.4+/-2.9), gluconeogenesis from glycerol (11.5+/-3.5), gluconeogenesis from the TCA cycle (67.3+/-5.6), glycogenolysis (1.0+/-0.8), pyruvate cycling (154.4+/-43.4), PEPCK flux (221.7+/-47.6), and TCA cycle flux (49.1+/-16.8). In a separate group of rats, glucose production was not different in the absence of (2)H(2)O and [U-(13)C]propionate, demonstrating that these tracers do not alter the measurement of glucose turnover.