Sustainable Polycaprolactone Polyol-Based Thermoplastic Poly(ester ester) Elastomers Showing Superior Mechanical Properties and Biodegradability.

Thermoplastic elastomers (TPEs) have attracted increasing attention for a wide variety of industrial and biomedical applications owing to their unique properties compared to those of traditional rubbers. To develop high-performance engineering TPEs and reduce the environmental pollution caused by plastic waste, α,ω-hydroxyl-terminated polycaprolactone (PCL) polyols with molecular weights of 1000-4200 g mol-1 and polydispersity index (Ð) of 1.30-1.88 are synthesized via the ring-opening polymerization of sustainable ε-caprolactone using a heterogeneous double metal cyanide catalyst. The resulting PCL polyols are employed as soft segments to produce thermoplastic poly(ester ester) elastomers and are compared to conventional thermoplastic poly(ether ester) elastomers prepared from polytetramethylene ether glycol (PTMEG). Notably, the PCL-based TPEs exhibit superior mechanical properties and biodegradability compared to PTMEG-based TPEs owing to their crystallinity and microphase separation behaviors. Accordingly, they have 39.7 MPa ultimate strength and 47.6% biodegradability, which are much higher than those of PTMEG-based TPEs (23.4 MPa ultimate strength and 24.3% biodegradability). The introduction of biodegradable PCLs demonstrates significant potential for producing biodegradable TPEs with better properties than polyether-derived elastomers.

Chemopreventive Activity of Ellagitannins from Acer pseudosieboldianum (Pax) Komarov Leaves on Prostate Cancer Cells.

Several studies have shown that compounds from Acer pseudosieboldianum (Pax) Komarov leaves (APL) display potent anti-oxidative, anti-inflammatory, and anti-proliferative activities. Prostate cancer (PCa) is the most common cancer among older men, and DNA methylation is associated with PCa progression. This study aimed to investigate the chemopreventive activities of the compounds which were isolated from APL on prostate cancer cells and elucidate the mechanisms of these compounds in relation to DNA methylation. One novel ellagitannin [komaniin (14)] and thirteen other known compounds, including glucose derivatives [ethyl-ß-D-glucopyranose (3) and (4R)-p-menth-1-ene-7,8-diol 7-O-ß-D-glucopyranoside (4)], one phenylpropanoid [junipetrioloside A (5)], three phenolic acid derivatives [ellagic acid-4-ß-D-xylopyranoside (1), 4-O-galloyl-quinic acid (2), and gallic acid (8)], two flavonoids [quercetin (11) and kaempferol (12)], and five hydrolysable tannins [geraniin (6), punicafolin (7), granatin B (9), 1,2,3,4,6-penta-galloyl-ß-D-glucopyranoside (10), and mallotusinic acid (13)] were isolated from APL. The hydrolyzable tannins (6, 7, 9, 10, 13, and 14) showed potent anti-PCa proliferative and apoptosis-promoting activities. Among the compounds, the ellagitannins in the dehydrohexahydroxydiphenoyl (DHHDP) group (6, 9, 13, and 14), the novel compound 14 showed the most potent inhibitory activity on DNA methyltransferase (DNMT1, 3a and 3b) and glutathione S-transferase P1 methyl removing and re-expression activities. Thus, our results suggested that the ellagitannins (6, 9, 13, and 14) isolated from APL could be a promising treatment option for PCa.

Highly Active Heterogeneous Double Metal Cyanide Catalysts for Ring-Opening Polymerization of Cyclic Monomers.

A series of heterogeneous Zn-Co double metal cyanide (DMC) catalysts were investigated for ring-opening polymerization (ROP) of various cyclic monomers. Notably, inexpensive and commonly used organic solvents such as acetone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, nitromethane, and 1-methylpyrrolidin-2-one were very effective complexing agents for the preparation of DMC catalysts, showing high catalytic activity for the ROP of propylene oxide, ε-caprolactone, and δ-valerolactone. The chemical structures and compositions of the resultant catalysts were determined using various techniques such as FT-IR, X-ray photoelectron spectroscopy, powder X-ray diffraction, and elemental analysis. α,ω-Hydroxyl-functionalized polyether and polyester polyols with high yields and tunable molecular weights were synthesized in the presence of various initiators to control functionality. Kinetic studies of the ROP of δ-valerolactone were also performed to confirm the reaction mechanism.

Porous SnO2 nanostructure with a high specific surface area for improved electrochemical performance.

Tin oxide (SnO2) has been attractive as an alternative to carbon-based anode materials because of its fairly high theoretical capacity during cycling. However, SnO2 has critical drawbacks, such as poor cycle stability caused by a large volumetric variation during the alloying/de-alloying reaction and low capacity at a high current density due to its low electrical conductivity. In this study, we synthesized a porous SnO2 nanostructure (n-SnO2) that has a high specific surface area as an anode active material using the Adams fusion method. From the Brunauer-Emmett-Teller analysis and transmission electron microscopy, the as-prepared SnO2 sample was found to have a mesoporous structure with a fairly high surface area of 122 m2 g-1 consisting of highly-crystalline nanoparticles with an average particle size of 5.5 nm. Compared to a commercial SnO2, n-SnO2 showed significantly improved electrochemical performance because of its increased specific surface area and short Li+ ion pathway. Furthermore, during 50 cycles at a high current density of 800 mA g-1, n-SnO2 exhibited a high initial capacity of 1024 mA h g-1 and enhanced retention of 53.6% compared to c-SnO2 (496 mA h g-1 and 23.5%).

Enhanced electrochemical performance of MoS2/graphene nanosheet nanocomposites.

Molybdenum disulfide (MoS2) is attractive as an anode material for next-generation batteries, because of its layered structure being favorable for the insertion/deinsertion of Li+ ions, and its fairly high theoretical capacity. However, since the MoS2 anode material has exhibited disadvantages, such as low electrical conductivity and poor cycling stability, to improve the electrochemical performance of MoS2 in this study, a nanocomposite structure consisting of MoS2 and GNS (MoS2/GNS) as an anode for LIBs was prepared, by controlling the weight ratios of MoS2/GNS. The X-ray diffraction patterns and electron microscopic analysis showed that the nanocomposite electrode structure consisted of well-formed MoS2 nanoparticles and GNS. Compared to MoS2-only, the MoS2/GNS composites exhibited high retention and improved capacity at high current densities. In particular, among these nanocomposite samples, MoS2/GNS(8 : 2) with an appropriate portion of GNS exhibited the best LIB performance, due to the lowest interfacial resistance and highest Li-ion diffusivity.

Solution-Processed Metal Coating to Nonwoven Fabrics for Wearable Rechargeable Batteries.

Wearable rechargeable batteries require electrode platforms that can withstand various physical motions, such as bending, folding, and twisting. To this end, conductive textiles and paper have been highlighted, as their porous structures can accommodate the stress built during various physical motions. However, fabrics with plain weaves or knit structures have been mostly adopted without exploration of nonwoven counterparts. Also, the integration of conductive materials, such as carbon or metal nanomaterials, to achieve sufficient conductivity as current collectors is not well-aligned with large-scale processing in terms of cost and quality control. Here, the superiority of nonwoven fabrics is reported in electrochemical performance and bending capability compared to currently dominant woven counterparts, due to smooth morphology near the fiber intersections and the homogeneous distribution of fibers. Moreover, solution-processed electroless deposition of aluminum and nickel-copper composite is adopted for cathodes and anodes, respectively, demonstrating the large-scale feasibility of conductive nonwoven platforms for wearable rechargeable batteries.

Rice husk-originating silicon-graphite composites for advanced lithium ion battery anodes.

Rice husk is produced in a massive amount worldwide as a byproduct of rice cultivation. Rice husk contains approximately 20 wt% of mesoporous SiO2. We produce mesoporous silicon (Si) by reducing the rice husk-originating SiO2 using a magnesio-milling process. Taking advantage of meso-porosity and large available quantity, we apply rice husk-originating Si to lithium ion battery anodes in a composite form with commercial graphite. By varying the mass ratio between these two components, trade-off relation between specific capacity and cycle life was observed. A controllable pre-lithiation scheme was adopted to increase the initial Coulombic efficiency and energy density. The series of electrochemical results suggest that rice husk-originating Si-graphite composites are promising candidates for high capacity lithium ion battery anodes, with the prominent advantages in battery performance and scalability.

Multiple daily injection of insulin regimen for a 10-month-old infant with type 1 diabetes mellitus and diabetic ketoacidosis.

The incidence of type 1 diabetes is increasing worldwide, and the greatest increase has been observed in very young children under 4 years of age. A case of infantile diabetic ketoacidosis in a 10-month-old male infant was encountered by these authors. The infant's fasting glucose level was 490 mg/dL, his PH was 7.13, his pCO2 was 15 mmHg, and his bicarbonate level was 5.0 mmol/L. The glycosylated hemoglobin level had increased to 9.4%. Ketonuria and glucosuria were detected in the urinalysis. The fasting C-peptide and insulin levels had decreased. The infant was positive for anti-insulin and antiglutamic acid decarboxylase antibodies. Immediately after the infant's admission, fluid therapy and intravenous insulin infusion therapy were started. On the second day of the infant's hospitalization and after fluid therapy, he recovered from his lethargic condition, and his general condition improved. Feeding was started on the third day, and he was fed a formula 5 to 7 times a day and ate rice, vegetables, and lean meat. Due to the frequent feeding, the frequency of rapid-acting insulin injection was increased from 3 times before feeding to 5 times, adjusted according to the feeding frequency. The total dose of insulin that was injected was 0.8-1.1 IU/kg/day, and the infant was discharged on the 12th day of his hospitalization. The case is presented herein with a brief review of the relevant literature.

Formula fed twin infants with recurrent hypocalcemic seizures with vitamin D deficient rickets and hyperphosphatemia.

Vitamin D deficient rickets is generally known to occur in breast fed infants. And excessive phosphate ingestion is a main cause of late onset hypocalcemia in formula fed infants. Here we introduce 45-day-old formula fed hypocalcemic twins with recurrent seizure attacks. They were diagnosed as having both of vitamin D deficient rickets and hyperphosphatemia. Radiologic findings indicated mild rickets and the twins were treated with calcium and alfacalcidol. After 3-5 months of oral supplementation, medication was discontinued in both twins. They showed normal growth and calcium, phosphorus, and vitamin D levels during the 6-month follow-up period. Twins can be at risk for hypocalcemia because of their high risk of vitamin D deficiency, low birth weight, and premature birth. Therefore twin pregnant women need ingestion of sufficient vitamin D and calcium.

Factors affecting capsular volume changes and association with outcomes after Bankart repair and capsular shift.

BACKGROUND: Capsular laxity is a main contributing factor in recurrent shoulder instability and is suggested to be correlated with increased capsular volume. Arthroscopic capsular shift combined with Bankart repair can reduce the capsular volume and reinforce the redundant capsule; however, as the capsuloligamentous structure has viscoelastic properties, it is possible for the shifted and tensioned capsule of the glenohumeral joint to slowly stretch out again over time, resulting in an increase in capsular volume. PURPOSE: To analyze changes in capsular volume of the glenohumeral joint over time after arthroscopic Bankart repair and capsular shift, the factors associated with these changes, and their relevance to outcomes. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Included in this study were 105 patients (mean age, 25.8 ± 8.2 years) who underwent arthroscopic Bankart repair and capsular shift for anterior shoulder instability and computed tomography arthrography (CTA) at 3 months and 1 year postoperatively and whose various functional outcomes were evaluated preoperatively and at the last follow-up (>12 months). Among these patients, 27 also had preoperative CTA. These 27 patients were used to make comparisons between preoperative and 3-month postoperative CTA measurements, and all 105 patients were used for all other comparisons. Two raters measured the separate anterior and posterior capsular volume and cross-sectional area at the 5-o'clock position using 3-dimensional (3D) Slicer software. These measurements were subsequently adjusted for each glenoid size. The changes in capsular volume and cross-sectional area at the 5-o'clock position over time, the factors related to higher change in anterior capsular volume, and their correlation with outcomes were evaluated. RESULTS: Three months postoperatively, the total and anterior capsular volume and anterior cross-sectional area significantly decreased; however, these values increased again at 1 year postoperatively (all P < .01). The inter- and intraobserver reliabilities of the measurements were excellent (interclass correlation coefficient = 0.717-0.945). Female sex, being an elite athlete, and more dislocations before surgery were related to a higher increase in anterior capsular volume at 1 year (all P < .05). Eight patients had redislocation, and 18 exhibited positive apprehension test postoperatively, and these patients showed significantly higher increases in anterior and total capsular volume at 1 year than did those without redislocation or positive apprehension sign (all P < .01). However, with the exception of Rowe score, a higher increase in anterior capsular volume was not related to functional outcome measures. CONCLUSION: Surgeons should be aware of the re-increase in anterior capsular volume or restretching trait of the anterior capsule over time, even after successful arthroscopic Bankart repair and capsular shift. In this study, women, elite athletes, and those with frequent dislocations were at high risk of capsular restretching. An increase in capsular volume was related to redislocation and positive apprehension sign as well as with Rowe score.

Automatic detection of inferior alveolar nerve canal from cone-beam computed tomography images for dental surgery planning.

The inferior alveolar nerve canal is an important nerve canal in the jaw bone, and any damage to this canal can cause pain or fatal complications. Since such damage can be caused by a wrong surgical procedure or surgery plan, accurate surgery planning is necessary. Cone-beam computed tomography (CBCT) is a three-dimensional medical imaging method that is mainly used in dental treatment; however, identifying the nerve canal is difficult in CBCT images as compared to conventional CT images. This paper proposes a new concept of a panoramic curve for nerve canal detection and a detection algorithm that is usually applied to facial recognition was introduced in this study for the automatic detection of nerve canal in CBCT images.

Optimized marker for template-guided intraoral surgery.

Template-guided intraoral surgery is attracting interest due to its accuracy and convenience. Usually, fiducial markers are used for registration of the different model coordinates for patients or plaster and fabrication coordinates in template-guided dental surgery. The accuracy of markers is important because it is directly related to the accuracy of the template-guide, which ultimately affects the success of surgical results. In this paper, we present the methods of determining optimal marker parameters such as size, shape, and material. We have defined parameters that could potentially influence the accuracy of markers and tested them with various values for each parameter. Experiments were performed to measure repeatability, and we tested accuracy and minimized potential error by comparing the actual and calculated dimensions. As a result, the following optimal marker parameters were identified: 3-mm diameter, positively tapered cylindrical shape, and titanium composition.

Novel methods for 3D postoperative analysis of total knee arthroplasty using 2D-3D image registration.

BACKGROUND: Radiographic evaluation of patients after total knee arthroplasty is an important tool for assessing the correct position of the implants and the axis of limb alignment because this will determine long-term durability of the implants. Recently, 2D-3D medical image registration methods are developed for 3D postoperative analysis of total knee arthroplasty. However, most of these techniques have focused only on knee implants. METHODS: A 2D-3D medical image registration is implemented to compute the 3D positions of not only implants but also lower limb bones. The following 3D postoperative analysis methods for total knee arthroplasty are presented in this paper: (1) automatic calculation of relative angles of implants and bones, (2) assessment of external rotation angles of inserted implants, and (3) measurement and comparison of both flexion-extension gap balances. Finally these methods have been applied in five patients who underwent total knee replacements. FINDINGS: A practical method that can evaluate the patient's knee conditions has been successfully developed. The repeatability and accuracy of 2D-3D registration were around 0.2mm as obtained from the tests using model bones. Based on the 3D information, the novel methods of postoperative analysis were proposed and successfully applied to the patients. INTERPRETATION: The 3D positions for both knee implants and lower limb bones can be calculated in order to perform comprehensive postoperative analyses of total knee arthroplasty. The proposed analyses of the postoperative evaluations facilitated various 3D evaluations of the status of implants, alignment of lower limb and gap balances which were not previously feasible.