-
1.
On the Future Design of Bio-Inspired Polyetheretherketone Dental Implants.
Knaus, J, Schaffarczyk, D, Cölfen, H
Macromolecular bioscience. 2020;(1):e1900239
Abstract
Polyetheretherketone (PEEK) is a promising implant material because of its excellent mechanical characteristics. Although this polymer is a standard material in spinal applications, PEEK is not in use in the manufacturing of dental implants, where titanium is still the most-used material. This may be caused by its relative bio-inertness. By the use of various surface modification techniques, efforts have been made to enhance its osseointegrative characteristics to enable the polymer to be used in dentistry. In this feature paper, the state-of-the-art for dental implants is given and different surface modification techniques of PEEK are discussed. The focus will lie on a covalently attached surface layer mimicking natural bone. The usage of such covalently anchored biomimetic composite materials combines many advantageous properties: A biocompatible organic matrix and a mineral component provide the cells with a surrounding close to natural bone. Bone-related cells may not recognize the implant as a foreign body and therefore, may heal and integrate faster and more firmly. Because neither metal-based nor ceramics are ideal material candidates for a dental implant, the combination of PEEK and a covalently anchored mineralized biopolymer layer may be the start of the desired evolution in dental surgery.
-
2.
A Randomized Trial Comparing the Bowel Cleansing Efficacy of Sodium Picosulfate/Magnesium Citrate and Polyethylene Glycol/Bisacodyl (The Bowklean Study).
Hung, SY, Chen, HC, Chen, WT
Scientific reports. 2020;(1):5604
Abstract
Bowel cleansing is essential for a successful colonoscopy, but the ideal clearing agent and the volume have yet to be determined. A small-volume cleanser is important for patient compliance. This study aimed to compare the bowel cleansing efficacy, safety, tolerability, and acceptability of a 300-mL small-volume sodium picosulfate/magnesium citrate (PSMC) preparation-Bowklean with one 2-L polyethylene glycol (PEG)/bisacodyl-Klean-Prep/Dulcolax preparation under identical dietary recommendations. This multicenter, randomized, parallel-group, pre-specified noninferiority study enrolled 631 outpatients scheduled to undergo colonoscopy (Bowklean = 316 and Klean-Prep/Dulcolax = 315). After bowel preparation, an independent evaluator blinded to the subject's treatment allocation rated the quality of the colon cleansing. Efficacy was evaluated using the Aronchick Scale and Ottawa Bowel Preparation Scale (OPBS). Safety was assessed by monitoring adverse events. Tolerability and acceptability were measured via a patient questionnaire. Bowklean was non-interior to Klean-Prep/Dulcolax in overall colon cleansing but was associated with significantly better preparation quality. Notably, Bowklean was associated with significantly greater tolerability and acceptability of bowel preparations than Klean-Prep/Dulcolax. Safety profiles did not differ significantly between the groups. Our data indicate that Bowklean is a more effective and better-tolerated bowel cleansing preparation before colonoscopy than Klean-Prep/Dulcolax. Bowklean may therefore increase positive attitudes toward colonoscopies and participation rates.
-
3.
Synthesis and assessment of CTAB and NPE modified organo-montmorillonite for the fabrication of organo-montmorillonite/alginate based hydrophobic pharmaceutical controlled-release formulation.
Yan, H, Chen, X, Bao, C, Yi, J, Lei, M, Ke, C, Zhang, W, Lin, Q
Colloids and surfaces. B, Biointerfaces. 2020;:110983
Abstract
The research goal of the present study was to develop a carrier for loading and controlled -release of the hydrophobic drug with the combined use of organo-montmorillonite (OMMT) and alginate. The OMMT was synthesized through the intercalation modification of sodium montmorillonite (Na-MMT) with cationic cetyltrimethylammonium bromide (CTAB), nonionic nonylphenol polyoxyethylene ether (NPE) and the mixture of them via simple and convenient wet ball-milling method. Furthermore, the organo-montmorillonite/alginate (OMMT/Alg) composite hydrogel beads with slow and controlled release properties were constructed by using alginate as a coating material under the exogenous cross-linking of calcium ions. The physical and chemical properties of OMMT were comparatively evaluated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), thermogravimetric analyzer (TGA), BET-specific surface area measurements, and drug adsorption experiments. Experimental results showed that the presence of CTAB was able to facilitate the intercalation of CTAB/NPE into Na-MMT through the cation exchange reaction. And the cationic CTAB and nonionic NPE were adsorbed or intercalated into the MMT lamellar structure through the wet ball-milling process, which could change the hydrophilic nature of Na-MMT and improve its affinity to the hydrophobic drug molecules. In addition, the OMMT/Alg composite hydrogel beads displayed superior sustained-release properties than Na-MMT/Alg, mainly ascribed to the good affinity of OMMT to hydrophobic drug that retarded the drug diffusion. In particular, CTA/NPE-MMT/Alg with the highest loading capacity (LC) and encapsulation efficiency (EE) revealed the optimal controlled performance for the release of hydrophobic ibuprofen. The release followed the Korsmeyer-Peppas model suggested non-Fickian diffusion release mechanism. Based on the high drug loading capacity and excellent controlled drug release properties, the CTA/NPE-MMT/Alg incorporating hydrophobic drugs into hydrophilic matrices could be a highly promising material for use in hydrophobic drug delivery.
-
4.
1L- vs. 4L-Polyethylene glycol for bowel preparation before colonoscopy among inpatients: A propensity score-matching analysis.
Frazzoni, L, Spada, C, Radaelli, F, Mussetto, A, Laterza, L, La Marca, M, Piccirelli, S, Cortellini, F, Rondonotti, E, Paci, V, et al
Digestive and liver disease : official journal of the Italian Society of Gastroenterology and the Italian Association for the Study of the Liver. 2020;(12):1486-1493
Abstract
BACKGROUND Inpatients are at risk for inadequate colon cleansing. Experts recommend 4L-polyethylene-glycol (PEG) solution. A higher colon cleansing adequacy rate for a hyperosmolar 1L-PEG plus ascorbate prep has been recently reported. AIMS We aimed to determine whether 1L-PEG outperforms 4L-PEG among inpatients. METHODS post-hoc analysis of a large Italian multicenter prospective observational study among inpatients (QIPS study). We performed a propensity score matching between 1L-PEG and 4L-PEG group. The primary outcome was the rate of adequate colon cleansing as assessed by unblinded endoscopists through Boston scale. Secondary outcome was the safety profile. RESULTS Among 1,004 patients undergoing colonoscopy, 724 (72%) were prescribed 4L-PEG and 280 (28%) 1L-PEG. The overall adequate colon cleansing rate was 69.2% (n = 695). We matched 274 pairs of patients with similar distribution of confounders. The rate of patients with adequate colon cleansing was higher in 1L-PEG than in 4L-PEG group (84.3% vs. 77.4%, p = 0.039). No different shift in serum concentration of electrolytes (namely Na+, K+, Ca2+), creatinine and hematocrit were observed for both preparations. CONCLUSION We found a higher rate of adequate colon cleansing for colonoscopy with the 1L-PEG bowel prep vs. 4L-PEG, with apparent similar safety profile, among inpatients. A confirmatory randomized trial is needed. (ClinicalTrials.gov no: NCT04310332).
-
5.
Application of polyetheretherketone cages through minimally invasive oblique retroperitoneal approach for the treatment of lumbar polymicrobial spondylodiscitis: A STROBE-compliant retrospective study with 7 cases.
Luo, W, Zhu, Y, Zhao, ZH, Ou, YS
Medicine. 2020;(17):e18594
-
-
Free full text
-
Abstract
Despite the plethora of evidence in support of the use of structural osseous autograft in lumbar spondylodiscitis, attention has recently been turned to the addition of synthetic materials such as polyetheretherketone (PEEK) to restore anterior vertebral column support.From January 2015 to April 2017, 7 patients with lumbar polymicrobial spondylodiscitis were surgically treated with a minimally invasive oblique retroperitoneal approach to the infected focus. The patients underwent a standard lateral minimally invasive oblique retroperitoneal approach using direct lateral interbody fusion system. The PEEK cages were loaded with autologous bone graft. All the patients underwent posterior fixation with percutaneous pedicle screw instrumentation. Lumbar function was measured using Oswestry Disability Index, and pain was measured with visual analog scale. Fusion and subsidence were also recorded.The study included 5 female and 2 male patients. The median age was 58.9 years. The duration of follow-up was 31.8 ± 6.1 months (range: 24-47). All patients recovered from the infection without relapse within 24-month follow-up. Visual analog scale significantly declined from 7.57 ± 0.53 before surgery to 1.57 ± 0.53 at 12-month follow-up. Mean Oswestry Disability Index decreased from 72.14 ± 6.82 before surgery to 22.28 ± 2.13 after surgery. All patients had solid fusion at 2-year follow-up. Fusion occurred at 6 to 15 months (mean 9.8 months).The specific use of PEEK cages in lumbar polymicrobial spondylodiscitis suggests reliable outcome in terms of clinical and imaging outcomes in our limited cases.
-
6.
Effect of the Ligand Binding Strength on the Morphology of Functionalized Gold Nanoparticles.
Chan, CH, Poignant, F, Beuve, M, Dumont, E, Loffreda, D
The journal of physical chemistry letters. 2020;(7):2717-2723
Abstract
Functionalized gold nanoparticles are investigated by density functional theory calculations in the context of cancer radiotherapy. Several typical experimental shapes, including nanostars, nanospheres, and nanorods, are modeled by optimizing Au clusters covered by organic monolayers composed of hydrated short-chain polyethylene glycol (PEG) ligands. The PEGylation stabilizes significantly the stellation of decahedral Au54 by deforming significantly its geometry at the spikes. The higher stability of the PEG molecules adsorbed on this stellated nanocluster with respect to the more spherical icosahedral Au55 and truncated octahedral Au79 leads to a larger energy cost to desorb them and thus a weaker propensity for the starred nanoparticle to exchange ligands with the cell membrane, in agreement with experiments. These results open interesting possibilities for advancing our understanding of the cellular uptake of gold nanoparticles.
-
7.
The Titanium-coated PEEK Cage Maintains Better Bone Fusion With the Endplate Than the PEEK Cage 6 Months After PLIF Surgery: A Multicenter, Prospective, Randomized Study.
Hasegawa, T, Ushirozako, H, Shigeto, E, Ohba, T, Oba, H, Mukaiyama, K, Shimizu, S, Yamato, Y, Ide, K, Shibata, Y, et al
Spine. 2020;(15):E892-E902
Abstract
STUDY DESIGN A multicenter, randomized, open-label, parallel-group trial. OBJECTIVE To investigate interbody bone fusion rates in titanium-coated polyetheretherketone (TiPEEK) and polyetheretherketone (PEEK) cages after posterior lumbar interbody fusion (PLIF) surgery. SUMMARY OF BACKGROUND DATA Previous clinical studies have not revealed any significant difference in bone fusion rates between TiPEEK and PEEK cages. METHODS During one-level PLIF surgery, 149 patients (84 men, 65 women, mean age 67 yr) were randomly allocated to use either a TiPEEK cage (n = 69) or PEEK cage (n = 80). Blinded radiographic evaluations were performed using computed tomography and assessed by modified intention-to-treat analysis in 149 cases and per-protocol analysis in 143 cases who were followed for 12 months. Clinical outcomes were assessed using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire and the Oswestry Disability Index. RESULTS The interbody union rate at 12 months after surgery was 45% owing to a very strict definition of bone fusion. The rates of bone fusion were significantly higher at 4 and 6 months after surgery in the TiPEEK group than in the PEEK group in the unadjusted modified intention-to-treat analysis and were significantly higher at 6 months in the unadjusted per-protocol analysis. Binary logistic regression analysis adjusted for sex, age, body mass index, bone mineral density, and surgical level showed that using a TiPEEK cage (odds ratio, 2.27; 95% confidence interval: 1.09-4.74; P = 0.03) was independently associated with bone fusion at 6 months after surgery. Japanese Orthopaedic Association Back Pain Evaluation Questionnaire and Oswestry Disability Index results improved postoperatively in both groups. CONCLUSION Using the TiPEEK cage for PLIF enabled the maintenance of better bone fusion to the endplate than using the PEEK cage at 6 months after the surgery. Our findings suggest the possibility of an earlier return to rigorous work or sports by the use of TiPEEK cage. LEVEL OF EVIDENCE 1.
-
8.
The advantage of polyethylene glycol electrolyte solution combined with lactulose in patients with long interval preparation-to-colonoscopy.
Yuanchao, H, Xueping, L, Tao, L, Jianping, N, Man, M
The Turkish journal of gastroenterology : the official journal of Turkish Society of Gastroenterology. 2020;(1):23-29
Abstract
BACKGROUND/AIMS: The main aim of the present study was to assess the efficacy of polyethylene glycol electrolyte (PEG) solution combined with lactulose in bowel preparation to find a new method for colonoscopy preparation to improve the quality of colonoscopy in patients with long interval preparation-to-colonoscopy (P-C). MATERIALS AND METHODS A prospective, randomized, endoscopist-blinded and placebo-controlled study was conducted. Three hundred sixty patients who were scheduled for colonoscopy were enrolled in the study. They were randomly divided into the PEG-lactulose group and the PEG-placebo group with 180 patients per arm. Two of the most common methods for estimating the quality of bowel preparation were the use of the Boston Bowel Preparation Scale and the measurement of the Bubble Scale and adenoma detection rate (ADR) as a secondary outcome of observation. RESULTS The PEG-lactulose group had a significant improvement in the quality of bowel preparation compared with the PEG-placebo group including colon cleanliness in interval P-C at 8 and 9 h (p<0.05) and bubble elimination in interval P-C at 5, 6, 7, 8, and 9 h (p<0.05). Compared with the PEG-placebo group, the ADR (23.3% vs. 15.0%, p<0.05) and the size (≤5 mm) of the adenoma (45.2% vs. 18.5%, p<0.05) increased in the PEG-lactulose group, and there were significant differences between the two groups. CONCLUSION PEG solution combined with lactulose can improve the quality of colonoscopy in patients with long interval P-C to allow the patients to select more flexible colonoscopy time. It is worth further popularizing in clinical practice.
-
9.
PEEK versus metal cages in posterior lumbar interbody fusion: a clinical and radiological comparative study.
Cuzzocrea, F, Ivone, A, Jannelli, E, Fioruzzi, A, Ferranti, E, Vanelli, R, Benazzo, F
Musculoskeletal surgery. 2019;(3):237-241
Abstract
BACKGROUND Low back pain and sciatica represent a common disabling condition with a significant impact on the social, working and economic lives of patients. Transforaminal lumbar interbody fusion (TLIF) is a surgical procedure used in degenerative spine conditions. Several types of cages were used in the TLIF procedure. PURPOSE To determine whether there is a difference in terms of symptomatology improvement, return to daily activities and fusion rate between metal cages and polyetheretherketone (PEEK) cages. METHODS We have retrospectively reviewed 40 patients who have undergone TLIF from October 2015 to May 2016. All patients were clinically evaluated with questionnaires and were assessed with CT scan and standing X-ray films of the full-length spine. RESULTS We found no significant functional differences in the two groups. At 1-year follow-up, osteolysis was present in 50% of cases of the PEEK cages and in 10% cases of the metal cages. The degree of fusion at 1 year was evaluated as complete in 40% cases of the metal cages and 15% cases of the PEEK cages. CONCLUSIONS We have found a better fusion rate and prevalence of fusion in the group treated with metal cages, reflecting the well-known osteoinductive properties of titanium and tantalum.
-
10.
Can a 1-day clear liquid diet with a split -dose polyethylene glycol overcome conventional practice patterns during the preparation for screening colonoscopy?
Özer Etik, D, Suna, N, Gündüz, C, Bostan, A, Özdemir, A, Gürel, BY, Yenişekerci, E, Boyacıoğlu, AS
The Turkish journal of gastroenterology : the official journal of Turkish Society of Gastroenterology. 2019;(9):817-825
Abstract
BACKGROUND/AIMS: A successful screening colonoscopy is closely linked to the quality of a bowel preparation. In this study, we aimed to determine the impact of a 1-day clear liquid diet (CLD) compared to a 3-day combined diet (CMD) accompanied by a split-dose regimen of polyethylene glycol and electrolyte lavage solution (PEG-ELS) for screening colonoscopy. MATERIALS AND METHODS This was a prospective, randomized, endoscopist-blinded study. Patients referred for screening colonoscopy were randomized to four groups as a 1-day CLD+PEG-ELS vs. a 1-day CLD+sulfate free (SF)-PEG-ELS and a 3-day CMD+PEG-ELS vs. a 3-day CMD+SF-PEG-ELS. An assessment of the quality of colon cleaning, tolerability to the preparation, and symptoms related to the preparation were recorded. RESULTS A total of 506 patients were enrolled in this study. The quality of bowel preparation was significantly inferior in the CMD+PEG-ELS group than CLD+PEG-ELS (p=0.004) and CMD+SF-PEG-ELS groups (p=0.007). There were no statistical differences among the groups in terms of the polyp detection rate. With respect to an easy rating of diet following and the consumption of laxative, there were no significant differences among the four groups. Gastric fullness and nausea/vomiting were pointed out much more, especially in the SF-PEG-ELS users (p=0.008 and p=0.004, respectively). CONCLUSION A 1-day CLD was not inferior to a 3-day CMD for colonoscopy preparation in terms of bowel cleaning, the polyp detection rate, and patient tolerance.