Surgical Landmark of Mandible Angle in the Identification of Cervical Spinal Level.

Mandible angle is considered to be a consistently palpable external landmark for the identification of cervical spinal level by a radiographic study. But this anatomical study aimed to determine the positional relationship between mandible angle and cervical spinal level in cadavers. In this study, the cervical spine of 10 adult cadavers with intact head and neck structure, including 6 males and 4 females, was dissected, and the position of mandible angle (MA) relative to the corresponding cervical spinal level was measured when the head was fixed in the flexion, anatomy position, and extension. The difference between the genders and the sides was analyzed. On the basis of the study of the corpse samples, the reference level of cervical spine was approximated to C2/3 intervertebral disc. The result has confirmed MA as a consistent and convenient landmark in the identification of cervical spinal level. Given some external landmarks do not consistently correspond to the exact level of the cervical spine, MA provides the relatively consistent reference point: C2/3 intervertebral disc. The authors hold that MA is a superior external landmark, which can help surgeons to localize the skin incision before anterior cervical spine surgery.

Preparation and pharmacokinetics study on gastro-floating sustained-release tablets of troxipide.

The purpose of this research aimed at preparing gastro-floating sustained-release tablets of troxipide and a further study on in vitro release and in vivo bioavailability. Under the circumstances of direct powder compression, the floating tablets were successfully prepared with HPMC as main matrix material, Carbopol as assistant matrix material, octadecanol as floating agent and sodium bicarbonate as foaming agent to float by gas-forming. The floating time and accumulative release amount as evaluation indexes were utilized to perform pre-experiment screening and single-factor test, respectively, while central composite design response surface method was applied for formulation optimization, followed by in vivo pharmacokinetic study in beagles after oral administration for floating tablets and commercial tablets used as the control. The results indicated that the floating sustained-release tablets held a better capability for floating and drug release and more satisfactory pharmacokinetic parameters, such as a lower Cmax, a prolonged Tmax, but an equivalent bioavailability calculated by AUC0-24 compared to commercial tablets. So a conclusion was finally drawn that the floating sustained-release tablets possessing a good release property could be suitable for demands of design.

The Effect of Using Premedication of Simethicone/Pronase With or Without Postural Change on Visualization of the Mucosa Before Endoscopy: A Prospective, Double Blinded, Randomized Controlled Trial.

INTRODUCTION: To investigate the efficacy and safety of preprocedural simethicone (S) and pronase (P) for optimal mucosal visualization during esophagogastroduodenoscopy with sedation. The effect of postural change combined with premedication on mucosal visibility was also examined. METHODS: The study randomized 496 patients into 8 groups based on the type of premedication provided and whether a postural change occurred. The premedication in the control group was 100 mL of normal saline solution (NS). The remaining 3 intervention groups were administered 100 mL of simethicone alone (S), pronase solution alone (P), and simethicone plus pronase solution (S + P). Each group was classified into subgroups according to whether there was a postural change (PC). The mucosal visibility score (MVS), total mucosal visibility score (TVS), procedure time, water consumption for mucosal cleansing, and proportion of patients with diminutive lesions <5 mm were recorded. RESULTS: The P and S groups had a significantly better TVS than the NS group (11.86 ± 3.36 in group P vs 14.52 ± 2.57 in group NS, P < 0.001; 12.36 ± 2.93 in group S vs 14.52 ± 2.57 in group NS, P = 0.006). The TVS was better in the P group than in the S group (11.86 ± 3.36 vs 12.36 ± 2.93, P = 0.037). The MVS was significantly better in the esophagus and duodenum and worse in the upper and lower gastric body in the S group than in the P group. The P + S group had a significantly better TVS than the P and S groups (9.81 ± 2.90 in group P + S vs 11.86 ± 3.36 in group P and 12.36 ± 2.93 in group S, respectively, P < 0.001),\ and had a reduced amount of flushing water during the procedure (0 [interquartile range [IQR]: 0-33] mL in group P + S vs 40 [IQR: 0-70] mL in group P, P < 0.01; 0 [IQR: 0-33] mL in group P + S vs 50 [IQR: 20-98] mL in group S, P < 0.001). The TVS was significantly better in the P + S + PC group than in the P + S group (8.44 ± 2.10 vs 9.81 ± 2.90, P = 0.003). The MVS was significantly better in the gastric antrum, fundus, and upper and lower gastric body in the P + S + PC group than in the P + S group. There was no significant difference in the detection rate of diminutive lesions among the different groups during an endoscopic examination ( P > 0.05). DISCUSSION: The combination of preprocedural administration with simethicone and pronase achieved superior mucosal visualization compared with saline, simethicone, or pronase alone in patients receiving upper endoscopy. Postural change maneuvers performed before endoscopy further improved the mucosal visibility in most parts of the stomach when used with preprocedural simethicone and pronase.

Mitochondrial Targeted Thermosensitive Nanocarrier for Near-Infrared-Triggered Precise Synergetic Photothermal Nitric Oxide Chemotherapy.

Nitric oxide (NO) intervenes, that is, a potential treatment strategy, and has attracted wide attention in the field of tumor therapy. However, the therapeutic effect of NO is still poor, due to its short half-life and instability. Therapeutic concentration ranges of NO should be delivered to the target tissue sites, cell, and even subcellular organelles and to control NO generation. Mitochondria have been considered a major target in cancer therapy for their essential roles in cancer cell metabolism and apoptosis. In this study, mesoporous silicon-coated gold nanorods encapsulated with a mitochondria targeted and the thermosensitive lipid layer (AuNR@MSN-lipid-DOX) served as the carrier to load NO prodrug (BNN6) to build the near-infrared-triggered synergetic photothermal NO-chemotherapy platform (AuNR@MSN(BNN6)-lipid-DOX). The core of AuNR@MSN exhibited excellent photothermal conversion capability and high loading efficiency in terms of BNN6, reaching a high value of 220 mg/g (w/w), which achieved near-infrared-triggered precise release of NO. The outer biocompatible lipid layer, comprising thermosensitive phospholipid DPPC and mitochondrial-targeted DSPE-PEG2000-DOX, guided the whole nanoparticle to the mitochondria of 4T1 cells observed through confocal microscopy. In the mitochondria, the nanoparticles increased the local temperature over 42 °C under NIR irradiation, and a high NO concentration from BNN6 detected by the NO probe and DSPE-PEG2000-DOX significantly inhibited 4T1 cancer cells in vitro and in vivo under the synergetic photothermal therapy (PTT)-NO therapy-chemotherapy modes. The built NIR-triggered combination therapy nanoplatform can serve as a strategy for multimodal collaboration.

Waste to treasure: Superwetting foam enhanced by bamboo powder for sustainable on-demand oil-water separation.

Low-cost and sustainable superwetting materials are urgently required for oily wastewater treatment. Many poly(vinylidene fluoride) (PVDF)-based materials have been designed for oil-water separation. However, their fabrication processes frequently require toxic organic solvents and high-cost materials (e.g., carbon tubes and graphene). In this study, a highly porous and superhydrophobic bamboo powders (BP)-enhanced PVDF foam (SBPF) was fabricated via an organic solvent-free process. The SBPF exhibits efficient adsorption and recovery for various oils and organic solvents. Moreover, the SBPF shows high adsorption and separation performance under ultraviolet exposure and turbulent environments. It can also be used for water-in-oil emulsions separation, with a high separation efficiency more than 99.3 % under gravity. Interestingly, the amphiphilic PVDF-BP foam (ABPF) shows underwater superoleophobicity and underoil superhydrophobicity after delignification of SBPF. Owing to the conversion of wettability, it presents a high performance in treatment of both surfactant-stabilied water-in-oil and oil-in-water emulsions with the high separation efficiency achieving more than 99.6 % and 99.5 % respectively under gravity. In addition, the ABPF shows a high separation performance even after ten cycles. Hence, this fabricated organic solvent-free foams are promising candidates for sustainable on-demand separation of oils or organic solvents and water in complex environments.

Preparation and characterization of 5-fluorouracil pH-sensitive niosome and its tumor-targeted evaluation: in vitro and in vivo.

The purpose of this study was to investigate preparation, characterization and tumor-targeted effect of pH-sensitive niosomes, composed of a nonionic surfactant mixed with cholesteryl hemisuccinate (CHEMS), a derivative of cholesterol (CHOL), as a pH-sensitive molecule. CHEMS was synthesized with CHOL and succinic acid, the structure of which was analyzed by Mass spectrometry (MS) and ¹H Nuclear magnetic resonance (¹H NMR) spectrum. Niosomes were prepared via film hydration-probe ultrasound method. Both normal niosomes and pH-sensitive niosomes showed spherical morphology under transmission electron microscope (TEM) with a average particle sizes of 172 ± 6.2 nm and 153 ± 4.7 nm, respectively. The thermotropic behavior, structure changes and interaction of 5-fluorouracil (5-Fu) with other materials were characterized by differential scanning calorimetry (DSC), and the disappearance of the melting peak of drug revealed the fact that drug was encapsulated in niosomes. Bulk-equilibrium reverse-dialysis method was chosen to investigate the behavior of drug release from normal niosomes and pH-sensitive niosomes in different pH medium, and the results showed that the noisome containing CHEMS had a pH-sensitive property. Tumor-targeted effect was proved by the fact that pH-sensitive niosomes showed a remarkable high concentration in tumor site of the mice transplanted with tumor cell.

The variation in crown-root morphology of anterior teeth assessed with cone-beam computed tomography.

OBJECTIVE: To determine the discrepancy of crown-root morphology of anterior teeth, using cone-beam computed tomography (CBCT), and to provide a guidance for proper torque expression. METHODS: A total of eligible 200 CBCT were imported into Invivo v. 5.4 software, to obtain the middle labio-lingual sections of anterior teeth. AutoCAD 2007 software was applied to measure the crown-root angulation (Collum angle) and the angle formed by a tangent to the center of the labial surface and the long axis of the crown (labial surface angle). SPSS 18.0 was used for statistical comparisons of the two measurements, at the level of p< 0.05, and the Pearson correlation analysis was applied to investigate the association between the two measurements. RESULTS: The value of Collum angle in maxillary central incisor was close to 0°. Significantly negative Collum angle in lateral incisors and maxillary canine, and positive value in mandibular canine were detected (p < 0.001). The labial surface angle in canine was significantly greater than the intra-arch incisors (p< 0.001), and no significant difference was detected between the central and lateral incisors (p > 0.05). Notably, there was also a significant positive correlation between the two measurements. CONCLUSIONS: The crown-root angulations were greatly different among anterior teeth. Accompanying the obvious crown-root angulations, the canines both in maxillary and mandibular arches presented considerable labial surface curvatures. Hence, equivalent deviation during bracket bonding might cause greater torque expression error and increase the risk of alveolar fenestration and dehiscence.

The variation in crown-root morphology of anterior teeth assessed with cone-beam computed tomography

ABSTRACT Objective: To determine the discrepancy of crown-root morphology of anterior teeth, using cone-beam computed tomography (CBCT), and to provide a guidance for proper torque expression. Methods: A total of eligible 200 CBCT were imported into Invivo v. 5.4 software, to obtain the middle labio-lingual sections of anterior teeth. AutoCAD 2007 software was applied to measure the crown-root angulation (Collum angle) and the angle formed by a tangent to the center of the labial surface and the long axis of the crown (labial surface angle). SPSS 18.0 was used for statistical comparisons of the two measurements, at the level of p< 0.05, and the Pearson correlation analysis was applied to investigate the association between the two measurements. Results: The value of Collum angle in maxillary central incisor was close to 0°. Significantly negative Collum angle in lateral incisors and maxillary canine, and positive value in mandibular canine were detected (p < 0.001). The labial surface angle in canine was significantly greater than the intra-arch incisors (p< 0.001), and no significant difference was detected between the central and lateral incisors (p > 0.05). Notably, there was also a significant positive correlation between the two measurements. Conclusions: The crown-root angulations were greatly different among anterior teeth. Accompanying the obvious crown-root angulations, the canines both in maxillary and mandibular arches presented considerable labial surface curvatures. Hence, equivalent deviation during bracket bonding might cause greater torque expression error and increase the risk of alveolar fenestration and dehiscence.

RESUMO Objetivo: Determinar a discrepância na morfologia coroa-raiz de dentes anteriores, utilizando tomografia computadorizada de feixe cônico (TCFC), e fornecer parâmetros para a expressão apropriada do torque. Método: No total, 200 tomografias elegíveis foram importadas para o software Invivo 5.4 para obtenção das secções médias vestibulolinguais dos dentes anteriores. Osoftware AutoCAD 2007 foi usado para medir a angulação coroa-raiz (ângulo Collum) e o ângulo formado por uma tangente ao centro da superfície vestibular da coroa e o longo eixo da coroa (ângulo da superfície vestibular). O software SPSS 18.0 foi utilizado para as comparações estatísticas das duas medições, com nível de significância de p< 0,05, e a análise de correlação de Pearson foi aplicada para investigar a associação entre as duas medições. Resultados: O valor do ângulo Collum do incisivo central superior foi próximo a 0°. Foram detectados valores significativamente negativos para o ângulo Collum nos incisivos laterais e caninos superiores, mas valores positivos nos caninos inferiores (p< 0,001). O ângulo da superfície vestibular no canino foi significativamente maior do que nos incisivos intra-arcada (p< 0,001), e nenhuma diferença significativa foi detectada entre incisivos centrais e laterais (p> 0,05). Também foi observada uma correlação positiva significativa entre as duas medições. Conclusões: As angulações coroa-raiz foram muito diferentes entre os dentes anteriores. Os caninos superiores e inferiores apresentaram considerável curvatura na superfície vestibular, associada a uma evidente angulação coroa-raiz. Consequentemente, desvios durante a colagem de braquetes podem desencadear maior erro na expressão de torque e aumentar o risco de fenestração alveolar e deiscência, sendo necessária uma avaliação antes da colagem.

[A cone-beam CT study on morphology and position of condylar processes in skeletal Class III adult patients with mandibular deviation].

OBJECTIVE: To evaluate the morphology and position of condylar processes in skeletal Class III adult patients with mandibular deviation. METHODS: Twenty skeletal Class III adult patients with mandibular deviation were selected as the deviated group and twenty adults with normal occlusion were selected as the control group. Cone- beam CT (CBCT) scans of their temporomandibular joints were taken. The original data were reconstructed and rebuilt. A series of measurements of the condylar morphology and location were performed. The collected data were analyzed using paired t- test. RESULTS: In the deviated group, the deviated sides were smaller than the contralateral sides in the perpendicular height, volume, maximum area of axial plane and the height of condylar head. The contralateral condyle was positioned more posteriorly and laterally [(0.35 ± 0.10) and (0.58 ± 0.18) mm] than the deviated condyle (P < 0.05). CONCLUSIONS: Adult skeletal Class III patients with mandibular deviation had some extent of condyle asymmetry in both morphology and location.

[Study of molar furcal perforation repaired with iRoot BP].

OBJECTIVE: To evaluate the effect of furcal perforation treated with iRoot BP. METHODS: Forty newly extracted human maxillary and mandibular molars were collected. Holes in diameter of 2 mm were prepared at the roof of the central pulp cavity of 36 samples with high speed round ball diamond in order to make perforated model, and then equally and randomly divided them into two groups. The other intact four samples were used as the negative controls. In the experimental groups, group A were repaired by iRoot BP, group B were repaired by mineral trioxide aggregate(MTA). Three samples in each group were observed under scanning electron microscope(SEM), and microleakage of others was tested by measuring the concentration of leaked glucose with the enzymatic glucose oxidase-peroxidase (GOD-POD) method. RESULTS: Microleakage of group B was higher than group A and had statistical difference (P<0.05). The dentin and iRoot BP contacted more closely in group A, some gaps existed between the dentin and MTA in group B. CONCLUSION: For repairing furcal perforation, the effect of iRoot BP is better than that of MTA.

Low molecular weight chitosan-coated liposomes for ocular drug delivery: in vitro and in vivo studies.

In this study, low molecular weight chitosan coated liposomes (LCHL) were designed and prepared for ocular drug delivery, the coating mechanism was studied, and in vitro and in vivo characterization was conducted. The effects of molecular weight and concentration of low molecular weight chitosan on the liposomal coating were studied. The numeric relations between coating variables and coating efficiency were established using a mathematical model. Morphology of LCHL was examined by transmission electron microscopy (TEM). Cytotoxicity and cell internalization of FITC-BSA labeled LCHL in a rabbit conjunctival epithelium (RCE) cell line were studied. Cyclosporin A (CsA) was encapsulated as a model drug, and in vitro drug release and in vivo drug absorption were investigated. LCHL demonstrated low toxicity to RCE cells. In vitro drug release measurement showed that LCHL had a delayed release profile compared with non-coated liposomes. In vivo study in rabbits showed that the concentrations of CsA in cornea, conjunctiva, and sclera were remarkably increased by LCHL. In conclusion, LCHL might be a potential ocular drug carrier with characteristics such as prolonged drug retention, enhanced drug permeation, and biocompatibility.

Liposome coated with low molecular weight chitosan and its potential use in ocular drug delivery.

In this study liposome coated with low molecular weight chitosan (LCH) was proposed and investigated its in vitro and in vivo properties, and its potential use in ocular drug delivery was evaluated. LCH with a molecular weight of 8kDa was prepared and coated on liposome loaded with diclofenac sodium. The LCH coating changed the liposome surface charge and slightly increased its particle size, while the drug encapsulation was not affected. After coating, the liposome displayed a prolonged in vitro drug release profile. LCH coated liposome also demonstrated an improved physicochemical stability at 25 degrees C in a 30-day storage period. The ocular bioadhesion property was evaluated by rabbit in vivo precorneal retention, and LCH coated liposome achieved a significantly prolonged retention compared with non-coated liposome or drug solution. The LCH coating also displayed a potential penetration enhancing effect for transcorneal delivery of the drug. In the ocular tolerance study, no irritation or toxicity was caused by continual administration of LCH coated liposome in a total period of 7 days. In conclusion, the LCH coating significantly modified the properties of liposome and brought a series of notable advantages for ocular drug delivery.