The effect of aging on the accuracy of marginal adaptation and fracture resistance of CAD/CAM PEEK single crown restoration

Aim: In recent years, great advances have been made in the use of CAD/CAM to prepare fixed restorations. The marginal and internal fit of these restorations is a principal determinant for their clinical success. In addition, the nature of the oral environment affects the mechanical properties of these restorations. Therefore, this study aimed to investigate the effect of aging process under conditions that simulate the oral environment on the marginal adaptation, and, fracture resistance of crowns fabricated from polyether ether ketone (PEEK) using CAD/CAM methods. Methods: Twenty identical crown restorations were fabricated by using CAD/CAM methods to mill polyether ether ketone (PEEK) material. These crowns were produced by using a software design of an epoxy resin replica of the prepared maxillary first premolar tooth. All PEEK crowns were cemented and randomly divided into two equal groups (A, B). Each group was divided into subgroups (A1, A2 and B1, B2). Group A1 and A2 were used to measure marginal adaptation and fracture resistance, respectively, before aging, while group (B1 and B2) were measured after aging. The cemented crowns were mounted in resin molds to facilitate the sectioning process. The measurements of the marginal gap were performed after sectioning at four points using a stereomicroscope. The fracture resistance of the crowns was investigated using a universal testing machine. A statistical analysis was performed using the GraphPad Prism® software version and unpaired Student's t-test. Results: The results revealed that aging affected the marginal gap, and the fracture resistance of the PEEK crowns. While aging, negatively affected the conditions under investigation, however the least significant difference of marginal gap was found in the margin region. Conclusions: PEEK-CAD/CAM is considered as a good alternative prosthodontic material for fixed prostheses. The CAD/CAM technique used to make PEEK crown restorations in our study offers the advantages of high marginal accuracy and fracture resistance for long-term performance in the oral environment

Multicenter real world study on the efficacy and safety of eribulin for the treatment of advanced breast cancer / 中华肿瘤杂志

Objective: To explore the efficacy and safety of real-world eribulin in the treatment of metastatic breast cancer. Methods: From December 2019 to December 2020, patients with advanced breast cancer were selected from Beijing Chaoyang District Sanhuan Cancer Hospital, Shandong Cancer Hospital, Peking University Cancer Hospital, Baotou Cancer Hospital, Shengjing Hospital Affiliated to China Medical University, and Cancer Hospital of Chinese Academy of Medical Sciences. Kaplan-Meier method and Log rank test were used for survival analysis, and Cox regression model was used for multivariate analysis. Results: The median progression-free survival (PFS) of 77 patients was 5 months, the objective response rate (ORR) was 33.8%, and the disease control rate (DCR) was 71.4%. The ORR of patients with triple-negative breast cancer was 23.1%, and the DCR was 57.7%; the ORR of patients with Luminal breast cancer was 40.0%, and the DCR was 77.8%; the ORR of patients with HER-2 overexpression breast cancer was 33.3%, and the DCR was 83.3%. ORR of 50.0% and DCR of 66.7% for patients treated with eribulin as first to second line treatment, ORR of 29.4% and DCR of 76.5% for patients treated with third to fourth line and ORR of 28.6% and DCR of 71.4% for patients treated with five to eleven line. The ORR of patients in the eribulin monotherapy group was 40.0% and the DCR was 66.0%; the ORR of patients in the combination chemotherapy or targeted therapy group was 22.2% and the DCR was 81.5%. Patients with a history of treatment with paclitaxel, docetaxel, or albumin paclitaxel during the adjuvant phase or after recurrent metastasis had an ORR of 32.9% and a DCR of 69.9% when treated with eribulin. The treatment efficacy is an independent prognostic factor affecting patient survival (P<0.001). The main adverse reactions in the whole group of patients were Grade Ⅲ-Ⅳ neutrophil decline [29.9% (23/77)], and other adverse reactions were Grade Ⅲ-Ⅳ fatigue [5.2% (4/77)], Grade Ⅲ-Ⅳ peripheral nerve abnormality [2.6% (2/77)] and Grade Ⅲ-Ⅳ alopecia [2.6% (2/77)]. Conclusions: Eribulin still has good antitumor activity against various molecular subtypes of breast cancer and advanced breast cancer that has failed multiple lines of chemotherapy, and the adverse effects can be controlled, so it has a good clinical application value.

Modification of polyetheretherketone (PEEK) physical features to improve osteointegration / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Polyetheretherketone (PEEK) has been widely applied in orthopedics because of its excellent mechanical properties, radiolucency, and biocompatibility. However, the bioinertness and poor osteointegration of PEEK have greatly limited its further application. Growing evidence proves that physical factors of implants, including their architecture, surface morphology, stiffness, and mechanical stimulation, matter as much as the composition of their surface chemistry. This review focuses on the multiple strategies for the physical modification of PEEK implants through adjusting their architecture, surface morphology, and stiffness. Many research findings show that transforming the architecture and incorporating reinforcing fillers into PEEK can affect both its mechanical strength and cellular responses. Modified PEEK surfaces at the macro scale and micro/nano scale have positive effects on cell-substrate interactions. More investigations are necessary to reach consensus on the optimal design of PEEK implants and to explore the efficiency of various functional implant surfaces. Soft-tissue integration has been ignored, though evidence shows that physical modifications also improve the adhesion of soft tissue. In the future, ideal PEEK implants should have a desirable topological structure with better surface hydrophilicity and optimum surface chemistry.

In vivo study of liposome-modified polyetheretherketone implant on bacteriostasis and osseointegration / 北京大学学报(医学版)

OBJECTIVE@#To develop dexamethasone plus minocycline-loaded liposomes (Dex/Mino liposomes) and apply them to improve bioinert polyetheretherketone (PEEK) surface, which could prevent post-operative bacterial contamination, enhance ossification for physiologic osseointegration, and finally reduce implant failure rates.@*METHODS@#Dex/Mino liposomes were covalently grafted onto the PEEK surface using polydopamine (pDA) coating as a medium. Confocal laser scanning microscopy was used to confirm the binding of fluorescently labeled liposomes onto the PEEK substrate, and a microplate reader was used to semiquantitatively measure the average fluorescence intensity of fluorescently labeled liposome-decorated PEEK surfaces. Moreover, the mouse subcutaneous infection model and the beagle femur implantation model were respectively conducted to verify the bioactivity of Dex/Mino liposome-modified PEEK in vivo, by means of micro computed tomography (micro-CT) and hematoxylin and eosin (HE) staining analysis.@*RESULTS@#The qualitative and quantitative results of fluorescently labeled liposomes showed that, the red fluorescence intensity of the PEEK-pDA-lipo group was stronger than that of the PEEK-NF-lipo group (P < 0.05); the liposomes were successfully and uniformly decorated on the PEEK surfaces due to the pDA coating. After mouse subcutaneous implantation of PEEKs for 24 hours, HE staining results showed that the number of inflammatory cells in the PEEK-Dex/Mino lipo group were lower than that in the inert PEEK group (P < 0.05), indicating a lower degree of infection in the test group. These results suggested that the Mino released from the liposome-functionalized surface provided an effective bacteriostasis in vivo. After beagle femoral implantation of PEEK for 8 weeks, micro-CT results showed that the PEEK-Dex/Mino lipo group newly formed more continuous bone when compared with the inert PEEK group; HE staining results showed that more new bones were formed in the PEEK-Dex/Mino lipo group than in the inert PEEK group, which were firmly bonded to the functionalized PEEK surface and extended along the PEEK interface. These results suggested that the Dex released from the liposome-functionalized surface induced effective bone regeneration in vivo.@*CONCLUSION@#Dex/Mino liposome modification enhanced the bioactivity of inert PEEK, the functionalized PEEK with enhanced antibacterial and osseointegrative capacity has great potential as an orthopedic/dental implant material for clinical application.

Systematic evaluation on efficacy and safety of Gingko Ketone Ester Dropping Pills in treatment of angina pectoris and coronary heart disease / 中国中药杂志

To systemically evaluate the efficacy and safety of Gingko Ketone Ester Dropping Pills in treating angina pectoris and co-ronary heart disease. CNKI, Wanfang, SinoMed, PubMed, Cochrane Library and EMbase databases were retrieved on computer, and the randomized clinical trial(RCT) on Gingko Ketone Ester Dropping Pills in treating angina pectoris and coronary heart disease, which were published from the database establishment to December 31, 2019, were comprehensively collected. Literature screening, data extraction and quality evaluation were conducted independently by two researchers according to inclusion and exclusion criteria. Literature methodology quality evaluation was conducted with use of the Cochrane Handbook 5.3.0(bias risk assessment tool). Meta-analysis was performed with RevMan 5.3.0 software. A total of 10 RCTs were included. The results of the Meta-analysis showed that as compared with conventional Western medicine alone, the application of Gingko Ketone Ester Dropping Pills combined with conventional Western medicine treatment further improved the total effective rate and electrocardiogram effect(RR=1.43,95%CI[1.20,1.71],P<0.000 1). There were statistically significant differences in the number of angina attacks, the duration of angina and the amount of nitroglycerin used. In terms of safety indicators, four studies reported adverse reactions in the experimental group, including facial flu-shing, tachycardia, dizziness, dyspnea, nausea and other symptoms. Based on the existing findings, in the treatment of angina pectoris and coronary heart disease, Gingko Ketone Ester Dropping Pills combined with conventional Western medicine can improve the clinical total effective rate, electrocardiogram effect, number of angina attacks, duration of angina and the amount of nitroglycerin used. However, in the included studies, due to some methodological quality problems which would impact the reliability of literature results more high-quality randomized controlled trials are still needed for further verification.

Effect of two kinds of surface pretreatments on bending strength to the modified polyetheretherketone / 华西口腔医学杂志

OBJECTIVE@#To evaluate the effect of sandblasting or acid etching on the three-point bending strength to the modified polyetheretherketone (PEEK).@*METHODS@#Forty-eight bars (15 mm×2 mm×1 mm) of specimens were fabricated from the modified PEEK (BioHPP). They were randomly divided into the following groups: A, B, C and D groups, which were blasted with alumina particles; E, F, and G groups, which were etched with 98% concentrated sulfuric acid; and control group H. The sand blast pressure of groups A, B and C was 0.2 MPa, and the grain sizes of the sand blasted were 120, 50, and 250 µm, respectively. Group D was blasted with 120 µm particle size at 0.7 MPa pressure. Groups E, F and G were acid etched for 60, 120, and 300 s, respectively. No surface treatment was conducted in group H. After all the specimens were processed, one sample was randomly selected from each group to observe its surface morphology under a scanning electron microscope (SEM), and the other specimens were tested for their three-point bending strength. SPSS 22.0 software was used to analyze the experimental data and to test whether the difference was statistically significant.@*RESULTS@#SEM observation showed that the surface morphology of the specimen changed after the treatment and revealed different degrees of cracks, pits, or voids. The three-point bending test indicated that the strength of the specimens treated with sandblasting or concentrated sulfuric acid decreased compared with that of the control group (P0.05). The strength of group D was lower than that of group A at the same particle size (P0.05).@*CONCLUSIONS@#The bending strength of BioHPP could be significantly decreased by surface sand blasting or concentrated sulfate etching as the sandblasting pressure increased, but the bending strength did not decrease as sand particle size and acid etching time changed.

The Potential Cardioprotective Mechanism of Sodium-Glucose Cotransporter 2 Inhibitors / 임상당뇨병

The potential mechanism by which sodium-glucose cotransporter 2 (SGLT2) inhibitors prevent cardiovascular disease (CVD) is being widely investigated. Improved insulin resistance, along with decreased body fat mass associated with SGLT2 inhibitor treatment is consistent with previously well-established factors contributing to the prevention of CVD. These factors are responsible for reduction of oxidative stress as well as improvement of systemic inflammation. Because heart failure was one of the most dramatically improved cardiovascular events in various clinical trials and because SGLT2 inhibitors promote osmotic diuresis and natriuresis, hemodynamic changes are considered as a critical mechanism responsible for the cardioprotective effect of SGLT2 inhibitors. Restored tubuloglomerular feedback by SGLT2 inhibitors might play a role in renoprotection, which in turn, leads to fewer CVDs. Finally, blood ketone body increments in response to SGLT2 inhibition might act as a “super-fuel” for salvaging the failing diabetic heart.

Evaluation of one-piece polyetheretherketone removable partial denture fabricated by computer-aided design and computer-aided manufacturing / 北京大学学报(医学版)

OBJECTIVE@#To explore a novel method for fabricating removable partial dentures (RPDs) using polyetheretherketone (PEEK) by computer-aided design and computer-aided manufacturing (CAD/CAM) technologies and to evaluate their fits for different assemblies in vitro.@*METHODS@#A standard stone cast of mandibular partial edentulous jaw was scanned using a lab scanner. Based on the digital cast, thirteen complete RPDs were designed combing dental CAD software and reverse engineering software, and then fabricated using PEEK by milling machine. Fits of assemblies were evaluated quantitatively by measuring the spaces between RPDs and casts. The gaps between RPDs and stone casts in different assemblies were duplicated using light-body silicone impression material and then measured using three-dimensional (3D) digital analysis methods in virtue of a dedicated software. Statistically, one-way analysis of variance (ANOVA) was used to compare the difference of gaps among assemblies in different shapes such as occlusal rest, denture base, and major connector. Paired-samples t test was used to compare the gaps difference for the similar shape assemblies in different areas.@*RESULTS@#One-piece PEEK RPDs were successfully designed and fabricated by CAD/CAM, and all the RPDs were well-seated on stone casts. The gaps between occlusal rests and casts [(84.3±23.6) μm] were significantly larger than those of denture bases [(32.5±27.8) μm] and major connectors [(49.9±47.0) μm], which meant that the fits of denture bases and major connectors were better than that of occlusal rests. However, the fits of all assemblies could be accepted clinically. For the similar shape assemblies in different areas, there were no significantly differences for gaps between distal extension denture bases [(25.1±55.3) μm] and non-extensive denture bases [(41.5±17.7) μm]. The gaps of occlusal rests adjacent and nonadjacent to the edentulous space were (86.1±29.8) μm and (80.8±42.1) μm respectively and there were no significantly difference between them either. These results implied that different locations had no apparent effect on the fits of assemblies.@*CONCLUSION@#With the computer-aided design and computer-aided manufacturing technology, PEEK can be used to fabricate one-piece removable partial dentures. And all assemblies of the one-piece PEEK RPDs showed satisfying fits in vitro, indicating a promising clinical application in the future.

Comparative study between Plate-Graff, Plate-Cage and PEEK cage in cervical spine fusion / Estudio comparativo entre Plate-Graff, Plate-Cage y Peek cage en la fusión de la columna cervical

Abstract: Objective: To compare results of Plate-Graff, Plate-Cage and PEEK cage in patients with cervical stenosis. Material and methods: Prospective, with before and after intervention and comparative study. From January 2005 to October 2011 we included 37 patients (male: 48.6%, female: 51.4%) post-surgery by anterior approach; 3 groups via: Group I, arthrodesis with Plate-Graff n = 12 (M 41.7%, F 58.3%) with 22 levels, group II, Plate-Cage n = 11 (M 63.6% 36.4% F) 19 levels, group III, PEEK cage, n = 14 (M 0% F 50%) with 25 levels. Functional assessment pre- and postoperative with neck disability index (NDI) and visual analogue scale for pain (VAS). The radiological assessment with X-rays only. Descriptive statistics were obtained. Wilcoxon method use according to data distribution, non parametric tests of ranges with sign of Kruskal-Wallis for comparison between more than two groups, and significance level with p < 0.05. We used the statistical package SPSS version 15. Results: The majority of patients was found between the sixth and eighth decade of life. At one year of follow up the NDI and pain with VAS shown improvement with statistical difference in three groups (p = 0.001). However, the radiographic measurements per year of follow-up showed a significant improvement of segmental lordosis (p = 0.02) only in patients with Plate-Graff. Conclusions: Using the graft offers best clinical and radiographic results compared with the Plate Cage and box peek to one year of follow-up.

Resumen: Objetivo: Comparar resultados de placa-injerto, caja-placa y caja-PEEK, en pacientes con conducto cervical estrecho. Material y métodos: Estudio prospectivo, en panel antes y después, de intervención y comparativo. De Enero de 2005 a Octubre de 2011, muestra de 37 pacientes (masculino: 48.6%, femenino: 51.4%) postoperados por vía anterior; formando tres grupos: grupo I, artrodesis con placa-injerto n = 12 (M 41.7%, F 58.3%) con 22 niveles; grupo II, caja-placa n = 11 (M 63.6%, F 36.4%) con 19 niveles; grupo III, caja-PEEK, n = 14 (M 50%, F 50%) con 25 niveles. La evaluación funcional pre- y postoperatoria mediante la escala de discapacidad cervical y escala visual análoga de dolor. La evaluación radiológica con radiografías de columna cervical. Se obtuvo estadística descriptiva. De acuerdo con la distribución de los datos se usaron pruebas no paramétricas de rangos con signo de Wilcoxon, y Kruskal-Wallis para comparación entre más de dos grupos. Con nivel de significancia de p<0.05. Se utilizó el paquete estadístico SPSS versión 15. Resultados: La mayoría de los pacientes se encontró entre la sexta y octava década de la vida. Al año de postoperados el índice de discapacidad cervical y mejoría del dolor con EVA mostraron mejoría con diferencia estadística en los tres grupos (p = 0.001). Sin embargo, las mediciones radiográficas al año de seguimiento mostraron una mejoría significativa de la lordosis segmentaria (p = 0.02) sólo en pacientes operados con placa-injerto. Conclusiones: El uso de la placa-injerto ofrece mejores resultados clínicos y radiográficos en comparación con la caja-placa y caja-PEEK, al año de seguimiento.

Marine drugs for cancer: surfacing biotechnological innovations from the oceans

This review will discuss the contributions of marine natural molecules, a source only recently found to have pharmaceutical prospects, to the development of anticancer drugs. Of the seven clinically utilized compounds with a marine origin, four are used for the treatment of cancer. The development of these drugs has afforded valuable knowledge and crucial insights to meet the most common challenges in this endeavor, such as toxicity and supply. In this context, the development of these compounds will be discussed herein to illustrate, with successful examples provided by cytarabine, trabectedin, eribulin and brentuximab vedotin, the steps involved in this process as well as the scientific advances and technological innovation potential associated with developing a new drug from marine resources.

Effects of body-shade resin layer thickness on the color of polyetheretherketone-Crea.lign restorations / 华西口腔医学杂志

OBJECTIVE@#This study aims to assess the effects of the different thicknesses of body-shade resin layers on the color of polyetheretherketone (PEEK)-Crea.lign restorations.@*METHODS@#Five PEEK specimens with the thickness of 0.6 mm were prepared. The color values of PEEK specimens were measured. Afterward, opaque-shade resin layers (0.1 mm) and body-shade resin layers (1.5 mm) were stacked with mold. The five specimens were evenly ground to a thickness of 1.4, 1.2, 1.0, 0.8, 0.6, 0.4, 0.2, and 0.0 mm in sequence. After grinding and ultrasonic cleaning, the color value was measured.@*RESULTS@#With the constant thickness of PEEK and 0.1 mm thickness of opaque-shade resin layer, the L*, a*, and b* values all showed downward trend with the increased thickness of the body-shade resin layer (1.0-1.4 mm). With the constant thickness of PEEK and 0.1 mm thickness of opaque-shade resin layer, the color difference between the adjacent groups was less than 1.5 NBS. This difference between nonadjacent groups was more than 1.5 NBS when the thickness of the body-shade resin layer reached 0.6 mm. Color difference between PEEK-Crea.lign restoration and PEEK was more than 1.5 NBS.@*CONCLUSIONS@#The thickness change in the body-shade resin layers influence the color of the PEEK-Crea.lign restorations. Using A2 shade Crea.lign, opaque-shade resin layer thickness is 0.1 and 0.6 mm thickness of body-shade resin layer can produce color which clinically acceptable.

Asymmetric bioreduction of ketoesters derivatives by Kluyveromyces marxianus: influence of molecular structure on the conversion and enantiomeric excess

ABSTRACT This study presents the bioreduction of six β-ketoesters by whole cells of Kluyveromyces marxianus and molecular investigation of a series of 13 β-ketoesters by hologram quantitative structure-activity relationship (HQSAR) in order to relate with conversion and enantiomeric excess of β-stereogenic-hydroxyesters obtained by the same methodology. Four of these were obtained as (R)-configuration and two (S)-configuration, among them four compounds exhibited >99% enantiomeric excess. The β-ketoesters series LUMO maps showed that the β-carbon of the ketoester scaffold are exposed to undergo nucleophilic attack, suggesting a more favorable β-carbon side to enzymatic reduction based on adopted molecular conformation at the reaction moment. The HQSAR method was performed on the β-ketoesters derivatives separating them into those provided predominantly (R)- or (S)-β-hydroxyesters. The HQSAR models for both (R)- and (S)-configuration showed high predictive capacity. The HQSAR contribution maps suggest the importance of β-ketoesters scaffold as well as the substituents attached therein to asymmetric reduction, showing a possible influence of the ester group carbonyl position on the molecular conformation in the enzyme catalytic site, exposing a β-carbon side to the bioconversion to (S)- and (R)-enantiomers.

The use of virtual surgical planning and navigation in the treatment of orbital trauma / 中华创伤杂志(英文版)

Virtual surgical planning (VSP) has recently been introduced in craniomaxillofacial surgery with the goal of improving efficiency and precision for complex surgical operations. Among many indications, VSP can also be applied for the treatment of congenital and acquired craniofacial defects, including orbital fractures. VSP permits the surgeon to visualize the complex anatomy of craniofacial region, showing the relationship between bone and neurovascular structures. It can be used to design and print using three-dimensional (3D) printing technology and customized surgical models. Additionally, intraoperative navigation may be useful as an aid in performing the surgery. Navigation is useful for both the surgical dissection as well as to confirm the placement of the implant. Navigation has been found to be especially useful for orbit and sinus surgery. The present paper reports a case describing the use of VSP and computerized navigation for the reconstruction of a large orbital floor defect with a custom implant.

Bonding of the Polymer Polyetheretherketone (PEEK) to Human Dentin: Effect of Surface Treatments

Abstract Polyetheretherketone (PEEK) is a material suitable for frameworks of fixed dental prostheses. The effect of different surface treatments on the bond strength of PEEK bonded to human dentin was evaluated. One hundred PEEK cylinders (3 mm×3 mm) were divided into five groups according to surface treatment: silica coating, sandblasting with 45 μm Al2O3 particles, etching with 98% sulfuric acid for 5, 30 and for 60 s. These cylinders were luted with resin cement onto 50 human molars. First, each tooth was embedded in epoxy resin and the buccal dentin surface was exposed. Then, two delimited dentin areas (Æ:3 mm) per tooth were etched with 35% phosphoric acid and bonded with a two-step self-priming adhesive system. After the luting procedure the specimens were stored in water (24 h/37 °C). Shear bond strength (SBS) was tested using a universal testing machine (crosshead speed 0.5 mm/min; load cell 50 kgf) and failure types were assessed. Stress data (MPa) were analyzed using the Kruskal-Wallis test. Comparison of the proportions of different failure types was performed using the Bonferroni method (p<0.05). Kruskal-Wallis demonstrated that differences among groups were not significant (p=0.187). Mean SBS were as follows: silica coating, 2.12±1.12 MPa; sandblasting, 2.37±0.86 MPa; sulfuric acid 5 s, 2.28±1.75 MPa; sulfuric acid 30 s, 1.80±0.85 MPa; sulfuric acid 60 s, 1.67±0.94 MPa. Adhesive and mixed failures were predominant in all groups. Both physical and chemical surface treatments produced adhesion between PEEK, resin cement and dentin.

Resumo O poli-éter-éter-cetona (PEEK) é um material indicado para as estruturas de próteses parciais fixas. O efeito de diferentes tratamentos de superfície na resistência de união entre PEEK e dentina humana foi avaliado. Cem cilindros de PEEK (3 mm×3 mm) foram divididos em cinco grupos de acordo com tratamento de superfície: silicatização, jateamento com partículas de Al2O3 45 µm, condicionamento com ácido sulfúrico 98% por 5, 30 e 60 s. Esses cilindros foram cimentados com cimento resinoso em cinquenta molares humanos. Primeiro, cada dente foi incluído em resina epóxica e a superfície dentinária vestibular foi exposta. Depois, duas áreas (Æ:3 mm) em dentina/por dente foram delimitadas, condicionadas com ácido fosfórico a 35% e receberam aplicação de um sistema adesivo de dois passos. Após o procedimento de cimentação, as amostras foram armazenadas em água (24 h/37 °C). A resistência da união ao cisalhamento (SBS) foi testada em uma máquina universal de ensaios (velocidade 0,5 mm/min; célula de carga 50 kgf), e foram avaliados os tipos de falha. Os dados de tensão (MPa) foram analisados pelo teste de Kruskal-Wallis. A comparação das percentagens de diferentes tipos de falha foi realizada utilizando o método de Bonferroni (p<0,05). O teste de Kruskal-Wallis demonstrou que as diferenças entre os grupos não foram significantes (p=0,187). As médias de SBS foram: silicatização, 2,12±1,12 MPa; jateamento, 2,37±0,86 MPa; ácido sulfúrico por 5 s, de 2,28±1,75 MPa; ácido sulfúrico por 30 s, 1,80±0,85 MPa, ácido sulfúrico por 60 s, 1,67±0,94 MPa. Falhas adesivas e mistas foram predominantes em todos os grupos. Ambos tratamentos de superfície, físicos e químicos, promoveram adesão entre PEEK, cimento resinoso e dentina.

Comparative in vitro evaluation of CAD/CAM vs conventional provisional crowns

ABSTRACT Objective This study compared the marginal gap, internal fit, fracture strength, and mode of fracture of CAD/CAM provisional crowns with that of direct provisional crowns. Material and Methods An upper right first premolar phantom tooth was prepared for full ceramic crown following tooth preparation guidelines. The materials tested were: VITA CAD-Temp®, Polyetheretherketone “PEEK”, Telio CAD-Temp, and Protemp™4 (control group). The crowns were divided into four groups (n=10), Group1: VITA CAD-Temp®, Group 2: PEEK, Group 3: Telio CAD-Temp, and Group 4: Protemp™4. Each crown was investigated for marginal and internal fit, fracture strength, and mode of fracture. Statistical analysis was performed using GraphPad Prism software version 6.0. Results The average marginal gap was: VITA CAD-Temp® 60.61 (±9.99) µm, PEEK 46.75 (±8.26) µm, Telio CAD-Temp 56.10 (±5.65) µm, and Protemp™4 193.07(±35.96) µm (P<0.001). The average internal fit was: VITA CAD-Temp® 124.94 (±22.96) µm, PEEK 113.14 (±23.55) µm, Telio CAD-Temp 110.95 (±11.64) µm, and Protemp™4 143.48(±26.74) µm. The average fracture strength was: VITA CAD-Temp® 361.01 (±21.61) N, PEEK 802.23 (±111.29) N, Telio CAD-Temp 719.24 (±95.17) N, and Protemp™4 416.40 (±69.14) N. One-way ANOVA test showed a statistically significant difference for marginal gap, internal gap, and fracture strength between all groups (p<0.001). However, the mode of fracture showed no differences between the groups (p>0.05). Conclusions CAD/CAM fabricated provisional crowns demonstrated superior fit and better strength than direct provisional crowns.

In-depth Medical Nutrition Therapy for a Woman with Diabetes: From Pregnancy to Delivery

Diabetes in pregnancy is associated with higher rates of miscarriage, pre-eclampsia, preterm labor, and fetal malformation. To prevent these obstetric and perinatal complications, women with diabetes have to control levels of blood sugar, both prior to and during pregnancy. Thus, individualized medical nutrition therapy for each stage of pregnancy is essential. We provided in-depth medical nutrition therapy to a 38-year-old pregnant woman with diabetes at all stages of pregnancy up to delivery. She underwent radiation therapy after surgery for breast cancer and was diagnosed with diabetes. At the time of diagnosis, her glycated hemoglobin level was 8.3% and she was planning her pregnancy. She started taking an oral hypoglycemic agent and received education regarding the management of diabetes and preconception care. She became pregnant while maintaining a glycated hemoglobin level of less than 6%. We provided education program for diabetes management during the pregnancy, together with insulin therapy. She experienced weight loss and ketones were detected; furthermore, she was taking in less than the recommended amount of foods for the regulation of blood sugar levels. By giving emotional support, we continued the counseling and achieved not only glycemic control but also instilled an appreciation of the importance of appropriate weight gain and coping with difficulties. Through careful diabetes management, the woman had a successful outcome for her pregnancy, other than entering preterm labor at 34 weeks. This study implicated that the important things in medical nutrition therapy for pregnant women with diabetes are frequent follow-up care and emotional approach through the pregnancy process.

Effect of phenolic ketones on ethanol fermentation and cellular lipid composition of Pichia stipitis / 生物工程学报

Lignin degradation products are toxic to microorganisms, which is one of the bottlenecks for fuel ethanol production. We studied the effects of phenolic ketones (4-hydroxyacetophenone, 4-hydroxy-3-methoxy-acetophenone and 4-hydroxy-3,5-dimethoxy-acetophenone) derived from lignin degradation on ethanol fermentation of xylose and cellular lipid composition of Pichia stipitis NLP31. Ethanol and the cellular fatty acid of yeast were analyzed by high performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS). Results indicate that phenolic ketones negatively affected ethanol fermentation of yeast and the lower molecular weight phenolic ketone compound was more toxic. When the concentration of 4-hydroxyacetophenone was 1.5 g/L, at fermentation of 24 h, the xylose utilization ratio, ethanol yield and ethanol concentration decreased by 42.47%, 5.30% and 9.76 g/L, respectively, compared to the control. When phenolic ketones were in the medium, the ratio of unsaturated fatty acids to saturated fatty acids (UFA/SFA) of yeast cells was improved. When 1.5 g/L of three aforementioned phenolic ketones was added to the fermentation medium, the UFA/SFA ratio of yeast cells increased to 3.03, 3.06 and 3.61, respectively, compared to 2.58 of the control, which increased cell membrane fluidity and instability. Therefore, phenolic ketones can reduce the yeast growth, increase the UFA/SFA ratio of yeast and lower ethanol productivity. Effectively reduce or remove the content of lignin degradation products is the key to improve lignocellulose biorefinery.

Frequent users of emergency services: associated factors and reasons for seeking care / Usuários frequentes de serviço de emergência: fatores associados e motivos de busca por atendimento / Usuarios frecuentes de servicios de emergencia: factores asociados y motivos de la búsqueda de atención

Aim: to identify the profile of frequent users of emergency services, to verify the associated factors and to analyze the reasons for the frequent use of the services. METHOD: An explanatory sequential type mixed method was adopted. Quantitative data were collected from the electronic medical records, with a sample of 385 users attended four or more times in an emergency service, during the year 2011. Qualitative data were collected through semi-structured interviews with 18 users, intentionally selected from the results of the quantitative stage. Quantitative data were analyzed using descriptive and inferential statistics and qualitative data using thematic analysis. RESULTS: It was found that 42.9% were elderly, 84.9% had chronic diseases, 63.5% were classified as urgent, 42.1% stayed for more than 24 hours in the service and 46.5% were discharged. Scheduled follow-up appointment, risk classification, length of stay and outcome were factors associated with frequent use. The reasons for seeking the services were mainly related to the exacerbation of chronic diseases, to easier access and concentration of technology, to the bond, and to the scheduled appointments. CONCLUSIONS: The results contribute to comprehending the repeated use of emergency services and provide additional data to plan alternatives to reduce frequent use. .

OBJETIVO: identificar o perfil de usuários frequentes de serviço de emergência, verificar fatores associados e analisar os motivos para utilização frequente do serviço. MÉTODO: adotou-se método misto, do tipo sequencial explanatório. Os dados quantitativos foram coletados em registros de prontuários eletrônicos, com amostra de 385 usuários, atendidos quatro vezes ou mais em um serviço de emergência, durante o ano de 2011. Os dados qualitativos foram obtidos por meio de entrevistas semiestruturadas, com 18 usuários, selecionados intencionalmente a partir dos resultados da etapa quantitativa. Os dados quantitativos foram analisados com estatística descritiva e inferencial e os qualitativos com análise temática. RESULTADOS: identificou-se que 42,9% eram idosos, 84,9% tinham doenças crônicas, 63,5% foram classificados como urgentes, 42,1% permaneceram mais de 24 horas no serviço e 46,5% tiveram alta. Os fatores associados à utilização frequente são retorno agendado, classificação de risco, tempo de permanência e desfecho. Os motivos da busca pelo serviço são relacionados, principalmente, à agudização de doenças crônicas, maior facilidade de acesso, concentração de tecnologia, vínculo e retornos agendados. CONCLUSÕES: os resultados contribuem para compreensão do uso repetido de serviços de emergência e oferecem subsídios para planejamento de alternativas para redução da utilização frequente. .

OBJETIVO: identificar el perfil de usuarios frecuentes de servicios de emergencia, verificar los factores asociados y analizar los motivos para utilización frecuente de ese servicio. MÉTODO: se adoptó un método mixto del tipo secuencial explicativo. Los datos cuantitativos fueron recolectados en registros de fichas electrónicas, con muestra de 385 usuarios atendidos cuatro veces o más, en un servicio de emergencia, durante el año de 2011. Los datos cualitativos fueron obtenidos por medio de entrevistas semiestructuradas con 18 usuarios, seleccionados intencionalmente a partir de los resultados de la etapa cuantitativa. Los datos cuantitativos fueron analizados con estadística descriptiva e inferencial y los cualitativos con análisis temático. RESULTADOS: se identificó que 42,9% eran ancianos, 84,9% tenían enfermedades crónicas, 63,5% fueron clasificados como urgentes, 42,1% permanecieron más de 24 horas en el servicio y 46,5% tuvieron alta para el domicilio. El retorno programado, la clasificación de riesgo, el tiempo de permanencia y el resultado, son factores asociados a la utilización frecuente. Los motivos de la búsqueda por el servicio son relacionados, principalmente a: la agudización de enfermedades crónicas, la mayor facilidad de acceso y concentración de tecnología, los vínculos, y a los retornos programados. CONCLUSIONES: los resultados contribuyen para la comprensión del uso repetido de servicios de emergencia y ofrecen informaciones para planificar alternativas para reducción de la utilización frecuente. .

Study of oral microbial adhesion and biofilm formation on the surface of nano-fluorohydroxyapatite/polyetheretherketone composite / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To develop novel polyetheretherketone (PEEK) based nanocomposites which possess the favorable antibacterial property, and to investigate the oral microbial adhesion and biofilm formation on the surfaces of PEEK, nano-fluorohydroxyapatite (n-FHA)-PEEK and nano-hydroxyaptite (n-HA)-PEEK.</p><p><b>METHODS</b>The bacterial adhesion and biofilm formation on the surfaces of n-FHA-PEEK, n-HA-PEEK were investigated via microbial viability assay kit and laser scanning confocal microscope (LSCM), respectively, with pure PEEK as control group.</p><p><b>RESULTS</b>No significantly statistical difference were found in the bacterial adhesion amounts on the surfaces of n-FHA-PEEK, n-HA-PEEK and PEEK at 1 h and 4 h. However, the number of bacteria on the n-FHA-PEEK surface decreased dramatically at 2 h (0.496 ± 0.008) compared with n-HA-PEEK groups (0.543 ± 0.015, P < 0.01). Although the biofilms formation on surfaces observed by LSCM had similar morphology and thickness at 3, 7, 14 d, that on the n-FHA-PEEK surface showed the highest dead-to-live bacteria ratio among the three materials at 14 d.</p><p><b>CONCLUSIONS</b>The combination of n-HA, especially for the n-FHA could inhibit the bacteria adhesion and accelerate the bacterial death, eventually may have an influence on the structure of biofilms and reduce the risk of peri-implantitis. Therefore, n-FHA-PEEK nanocomposites presented a good prospect for clinical applications as dental implant materials.</p>

Synthesis and antitumor activity of fluoroquinolon-3-yl-s-triazole sulfide ketones and their derivatives from ciprofloxacin / 药学学报

To discover an efficient strategy for the conversion of the antibacterial activity of fluoroquinolones into the antitumor activity, the three series of C-3 s-triazole-based derivatives including sulfide ketones (6a-6g), thiosemicarbazones (7a-7g) and fused heterocyclic thiazolotriazoles (8a-8g) were synthesized from ciprofloxacin (1), respectively. The structures were characterized by elemental analysis and spectral data. The antitumor activity was tested against three tumor cell lines (Hep-3B, Capan-1 and HL60) using the MTT assay. The three types of compounds all exhibited stronger anti-proliferative activities than ciprofloxacin in the test. The order of their activities was in compounds 7>8>6, and the order of selectivity against cancer cell lines was Capan-1, Hep-3B and HL60. Meanwhile, the SAR revealed that some compounds with electron-drawing group substituted such as fluoro- and nitro-phenyl compounds (6f, 7f, 8f) and (6g, 7g, 8g) displayed more significant activity than the control compounds, especially the IC50 values of thiosemicarbazone compounds 7f and 7g against Capan-1 was comparable to doxorubicin. Thus, a five-membered triazole as the C-3 bioisostere modified with the functionalized side-chain of sulfide-ketone thiosemicarbazone warrants special attention and further investigation.