Endoscopic transvestibular anatomy of the infratemporal fossa and upper parapharyngeal spaces for clinical surgery: a cadaver study.

AIMS: To investigate the anatomy of the infratemporal fossa (ITF) and to discuss the practicality of endoscopic transvestibular surgery for an ITF tumor. METHODS: Five fresh cadaveric specimens (10 sides) with vascular silicone injection were prepared for endoscopic anatomy. A transvestibular vertical incision was made along the ramus of the mandible, and pivotal nerves, arteries, and muscles were exposed to sculpt the anatomic landmarks of the ITF. RESULTS: The endoscopic transvestibular approach exposed the detailed structure of the ITF. The buccinator muscle and the adjoining superior pharyngeal constrictor muscle shaped the paramedian border of the ITF, while the medial pterygoid muscle (MPM) and the lateral pterygoid muscle formed the lateral border. The ITF was delimited by the skull base in the upper margin, and it was proximal to the parapharyngeal space in the inferior part. The inferior alveolar nerve was the first reference point, and the maxillary artery and the lateral pterygoid muscle were also the landmarks of the ITF. The lingual nerve, the eustachian tube (ET), and the middle meningeal artery were also located in the posterior part of the ITF. CONCLUSION: The endoscopic transvestibular approach provides a feasible and facile corridor to the ITF. With accurate hemostasis, this approach may provide another option for accessing the ITF for removal of tumors.

Web thickness determines the therapeutic effect of endoscopic keel placement on anterior glottic web.

This work is a retrospective analysis to investigate the critical risk factor for the therapeutic effect of endoscopic keel placement on anterior glottic web. Altogether, 36 patients with anterior glottic web undergoing endoscopic lysis and silicone keel placement were enrolled. Their voice qualities were evaluated using the voice handicap index-10 (VHI-10) questionnaire, and improved significantly 3 months after surgery (21.53 ± 3.89 vs 9.81 ± 6.68, P < 0.0001). However, 10 (27.8%) cases had web recurrence during the at least 1-year follow-up. Therefore, patients were classified according to the Cohen classification or web thickness, and the recurrence rates were compared. The distribution of recurrence rates for Cohen type 1 ~ 4 were 28.6, 16.7, 33.3, and 40%, respectively. The difference was not statistically significant (P = 0.461). When classified by web thickness, only 2 of 27 (7.41%) thin type cases relapsed whereas 8 of 9 (88.9%) cases in the thick group reformed webs (P < 0.001). These results suggest that the therapeutic outcome of endoscopic keel placement mostly depends on the web thickness rather than the Cohen grades. Endoscopic lysis and keel placement is only effective for cases with thin glottic webs. Patients with thick webs should be treated by other means.

Short-Term Dynamic Observation of the Color Change and Enhancement Effect of Polyethylenimine-Entrapped Gold Nanoparticles Used for Indirect Lymphography.

AIMS: To dynamically observe the color change and enhancement effect of gadolinium-loaded polyethylenimine-entrapped gold nanoparticles (Gd-Au PENPs) as a dual-mode CT/MRI contrast agent for sentinel lymph node (SLN) identification. METHODS: In 6 rabbits, Gd-Au PENPs were injected into the right side tongue submucosa, after which the color change of cervical draining lymph nodes was observed. Then the draining lymph nodes were examined by CT/MRI scan. Another 6 rabbits were randomly divided into a CT lymphography (CT-LG) and a MRI lymphography (MRI-LG) group and examined by CT/MRI scan 1 and 30 min after injection. Then SLNs were identified under the guidance of CT/MRI-LG. RESULTS: The ipsilateral afferent lymphatic vessels, cervical draining lymph nodes and efferent lymphatic vessels were stained black orderly and constantly after Gd-Au PENPs injection. Thirty minutes after injection, all cervical lymph nodes were excised to be examined by CT/MRI scan, and only the black-stained draining lymph nodes were enhanced. The 6 rabbits with CT/MRI-LG showed clear enhancement of SLNs. With indirect lymphography, the black-stained SLNs were easily visualized at autopsy. In all rabbits, the identification rate of lingual SLNs was 100%. CONCLUSIONS: Rabbit lingual SLNs could be identified with indirect lymphography using Gd-Au PENPs as a dual-mode contrast agent.

The impacts of microplastics on the cycling of carbon and nitrogen in terrestrial soil ecosystems: Progress and prospects.

As contaminants of emerging concern, microplastics (MPs) are ubiquitously present in almost all environmental compartments of the earth, with terrestrial soil ecosystems as the major sink for these contaminants. The accumulation of MPs in the soil can trigger a wide range of effects on soil physical, chemical, and microbial properties, which may in turn cause alterations in the biogeochemical processes of some key elements, such as carbon and nitrogen. Until recently, the effects of MPs on the cycling of carbon and nitrogen in terrestrial soil ecosystems have yet to be fully understood, which necessitates a review to summarize the current research progress and propose suggestions for future studies. The presence of MPs can affect the contents and forms of soil carbon and nitrogen nutrients (e.g., total and dissolved organic carbon, dissolved organic nitrogen, NH4+-N, and NO3--N) and the emissions of CH4, CO2, and N2O by altering soil microbial communities, functional gene expressions, and enzyme activities. Exposure to MPs can also affect plant growth and physiological processes, consequently influencing carbon fixation and nitrogen uptake. Specific effects of MPs on carbon and nitrogen cycling and the associated microbial parameters can vary considerably with MP properties (e.g., dose, polymer type, size, shape, and aging status) and soil types, while the mechanisms of interaction between MPs and soil microbes remain unclear. More comprehensive studies are needed to narrow the current knowledge gaps.

2D Nanozymes Modulate Gut Microbiota and T-Cell Differentiation for Inflammatory Bowel Disease Management.

Intestinal commensal microbiota dysbiosis and immune dysfunction are significant exacerbating factors in inflammatory bowel disease (IBD). To address these problems, Pluronic F-127-coated tungsten diselenide (WSe2 @F127) nanozymes are developed by simple liquid-phase exfoliation. The abundant valence transitions of elemental selenium (Se2- /Se4+ ) and tungsten (W4+ /W6+ ) enable the obtained WSe2 @F127 nanozymes to eliminate reactive oxygen/nitrogen species. In addition, the released tungsten ions are capable of inhibiting the proliferation of Escherichia coli. In a model of dextran sodium sulfate-induced colitis, WSe2 @F127 nanozymes modulate the gut microbiota by increasing the abundance of bacteria S24-7 and significantly reducing the abundance of Enterobacteriaceae. Moreover, WSe2 @F127 nanozymes inhibit T-cell differentiation and improve intestinal immune barrier function in a model of Crohn's disease. The WSe2 @F127 nanozymes effectively alleviate IBD by reducing oxidative stress damage, modulating intestinal microbial populations, and remodeling the immune barrier.

Non-invasive detection of mental fatigue in construction equipment operators through geometric measurements of facial features.

INTRODUCTION: Prolonged operation of construction equipment could lead to mental fatigue, which can increase the chances of human error-related accidents as well as operators' ill-health. The objective detection of operators' mental fatigue is crucial for reducing accident risk and ensuring operator health. Electroencephalography, photoplethysmography, electrodermal activity, and eye-tracking technology have been used to mitigate this issue. These technologies are invasive and wearable sensors that can cause irritation and discomfort. Geometric measurements of facial features can serve as a noninvasive alternative approach. Its application in detecting mental fatigue of construction equipment operators has not been reported in the literature. Although the application of facial features has been widespread in other domains, such as drivers and other occupation scenarios, their ecological validity for construction excavator operators remains a knowledge gap. METHOD: This study proposed employing geometric measurements of facial features to detect mental fatigue in construction equipment operators' facial features. In this study, seventeen operators performed excavation operations. Mental fatigue was labeled subjectively and objectively using NASA-TLX scores and EDA values. Based on geometric measurements, facial features (eyebrow, mouth outer, mouth corners, head motion, eye area, and face area) were extracted. RESULTS: The results showed that there was significant difference in the measured metrics for high fatigue compared to low fatigue. Specifically, the most noteworthy variation was for the eye and face area metrics, with mean differences of 45.88% and 26.9%, respectively. CONCLUSIONS: The findings showed that geometrical measurements of facial features are a useful, noninvasive approach for detecting the mental fatigue of construction equipment operators.

AIPH-Encapsulated Thermo-Sensitive Liposomes for Synergistic Microwave Ablation and Oxygen-Independent Dynamic Therapy.

Microwave ablation (MWA) is a novel treatment modality that can lead to the death of tumor cells by heating the ions and polar molecules in the tissue through high-speed vibration and friction. However, the single hyperthermia is not sufficient to completely inhibit tumor growth. Herein, a thermodynamic cancer-therapeutic modality has been fabricated which could be able to overcome hypoxia's limitations in the tumor microenvironment. Using thermo-sensitive liposomes (TSLs) and oxygen-independent radical generators (2,2'-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride [AIPH]), a nano-drug delivery system denoted as ATSL is developed for efficient sequential cancer treatment. Under the microwave field, the temperature rise of local tissue could not only lead to the damage of tumor cells but also induce the release of AIPH encapsulated in ATSL to produce free radicals, eliciting tumor cell death. In addition, the ATSL developed here would avoid the side effects caused by the uncontrolled diffusion of AIPH to normal tissues. The ATSLs have shown excellent therapeutic effects both in vitro and in vivo, suggesting its highly promising potential for clinic.

Low-density polyethylene microplastics and biochar interactively affect greenhouse gas emissions and microbial community structure and function in paddy soil.

Paddy soils are susceptible to microplastics (MPs) contamination. As a common soil amendment, biochar (BC) has been extensively applied in paddy fields. The co-occurrence of MPs and BC may cause interactive effects on soil biogeochemical processes, which has yet been well studied. In this study, a 41-days of microcosm experiment was conducted using paddy soil added with 0.5-1.5 wt% of low-density polyethylene (LDPE) and 5 wt% of BC individually or jointly. Application of BC, LDPE, or their mixture into soil significantly increased the emission of methane (CH4), but suppressed the emission of carbon dioxide (CO2). LDPE addition lowered soil nitrous oxide (N2O) emissions, while BC exerted an opposite effect. Proteobacteria was the most dominant phylum with a relative abundance range of 35.1-51.0%, followed by Actinobacteria (19.3-30.9%) and Acidobacteria (7.5-23.5%). The abundances of the mcrA gene and pH values were increased in soils added with BC or/and LDPE, which were the possible reasons for the higher CH4 emissions in these treatments. The emission of N2O was positively related to the abundances of norB and narG genes, suggesting denitrification was a major pathway to produce N2O. Results of structural equation modeling demonstrated that addition of BC or/and LDPE MPs could affect greenhouse gas emissions from paddy soil by altering soil chemical properties, microbial community structure, and functional gene abundances.

Formation and stability of electrostatic complexes formed between scallop female gonad protein isolates and sodium alginate: Influence of pH, total concentration, blend ratio, and ionic strength.

The complex coacervation between scallop (Patinopecten yessoensis) female gonad protein isolates (SFGPIs) and sodium alginate (SA) was determined by the turbidimetric method. The impact of pH, total biopolymer concentration, biopolymer blend ratio, and various salt ionic on the mechanisms governing the complex coacervation of SFGPIs-SA complexes were also investigated. For the SFGPIs:SA ratio of 2:1 without adding NaCl, insoluble and soluble complexes were observed at pH 5.8 (pHφ1 ) and pH 8.2 (pHc ) with the optimum biopolymer interactions appearing at pH 2.6 (pHopt ). The maximum turbidity value increased with the increment of the total biopolymer concentration from 0.37 to 1.83 until attaining the critical value (0.75%). As the blend ratios rose from 1:3 to 12:1, the critical pH values (pHc , pHφ1 , and pHopt ) moved to higher pH. Furthermore, the addition of NaCl led to a remarkable decrease in turbidity over the whole pH region in SFGPIs-SA complexes. Moreover, monovalent ions (Na+ and K+ ) had the same effect on the formation of the SFGPIs-SA complex, whereas the divalent cations (Mg2+ and Ca2+ ) lessened the complex formation in comparison with the monovalent ions. This study offers a methodological and theoretical basis for the design of complex SFGPIs-SA systems by understanding the complex coacervation under different conditions. PRACTICAL APPLICATION: In recent years, several protein-polysaccharides complexes have been widely applied in food and biological systems. Scallop (Patinopecten yessoensis) female gonads are deemed as good marine sources for developing protein matrices on account of their high protein content and nutrients. In our study, the effects of different conditions on the mechanisms governing the complex coacervation of SFGPI-SA mixtures were investigated, and the instability of the system could be overcome by understanding the conditions for SFGPIs/SA complex formation, which have a feasible role in developing marine source-protein as a functional food base such as kamaboko gels, can, sausage, fat substitutes, and delivery vehicles for bioactive compounds.

RGD-conjugated copolymer incorporated into composite of poly(lactide-co-glycotide) and poly(L-lactide)-grafted nanohydroxyapatite for bone tissue engineering.

Various surface modification methods of RGD (Arg-Gly-Asp) peptides on biomaterials have been developed to improve cell adhesion. This study aimed to examine a RGD-conjugated copolymer RGD/MPEG-PLA-PBLG (RGD-copolymer) for its ability to promote bone regeneration by mixing it with the composite of poly(lactide-co-glycotide) (PLGA) and hydroxyapatite nanoparticles surface-grafted with poly(L-lactide) (g-HAP). The porous scaffolds were prepared using solvent casting/particulate leaching method and grafted to repair the rabbit radius defects after seeding with autologous bone marrow mesenchymal cells (MSCs) of rabbits. After incorporation of RGD-copolymer, there were no significant influences on scaffold's porosity and pore size. Nitrogen of RGD peptide, and calcium and phosphor of g-HAP could be exposed on the surface of the scaffold simultaneously. Although the cell viability of its leaching liquid was 92% that was lower than g-HAP/PLGA, its cell adhesion and growth of 3T3 and osteoblasts were promoted significantly. The greatest increment in cell adhesion ratios (131.2-157.1% higher than g-HAP/PLGA) was observed when its contents were 0.1-1 wt % but only at 0.5 h after cell seeding. All the defects repaired with the implants were bridged after 24 weeks postsurgery, but the RGD-copolymer contained composite had larger new bone formation and better fusion interface. The composites containing RGD-copolymer enhanced bone ingrowth but presented more woven bones than others. The combined application of RGD-copolymer and bone morphological protein 2 (BMP-2) exhibited the best bone healing quality and was recommended as an optimal strategy for the use of RGD peptides.

PEGylated Indium Nanoparticles: A Metallic Contrast Agent for Multiwavelength Photoacoustic Imaging and Second Near-Infrared Photothermal Therapy.

Indium, a low melting point metal, is well-known for constructing eutectic gallium-indium liquid metal. However, unlike liquid metal nanoparticles, the biomedical applications of metallic indium nanoparticles (In NPs) remain in their infancy. Herein, an ultrasound-assisted liquid-reduction synthesis strategy was developed to prepare PEGylated In NPs, which were then used as a high-performance contrast agent for enhancing multiwavelength photoacoustic imaging and second near-infrared (NIR-II) photothermal therapy of the 4T1 breast tumor. The obtained In NPs depicted remarkable optical absorption from the first near-infrared (NIR-I) to NIR-II region and a high photothermal conversion efficiency of 41.3% at 1064 nm, higher than the majority of conventional NIR-II photothermal agents. Upon injection into the tumor, the photoacoustic intensities of the tumor section post-injection were obviously increased by 2.59-, 2.62-, and 4.27-fold of those of pre-injection by using excitation wavelengths of 750, 808, and 970 nm, respectively, depicting an excellent multiwavelength contrast capability of photoacoustic imaging. In addition, efficient ablation of the 4T1 tumor was achieved through the photothermal performance of PEGylated In NPs under NIR-II laser irradiation. Importantly, as the widely used element in the clinic, In NPs were highly biocompatible in vitro and in vivo. Therefore, this work pioneered the biomedical applications of PEGylated In NPs for cancer diagnosis and treatment.

Risk Factors of Difficult Pharyngeal Accidental Fishbones Ingestion.

OBJECTIVE: Accidental pharyngeal fishbone ingestion is a common complaint in ear, nose, and throat clinics. Approximately two-thirds of the accidentally ingested fishbones can be removed using tongue depressors and indirect laryngoscopy. However, the remaining third is challenging to identify and remove using these methods. These difficult fishbones require identification and removal via more advanced approaches. Video-guided laryngoscope is used to deal with difficult fishbones in our center. This study aimed to explore the risk factors for difficult fishbones. METHODS: A prospective study was performed at a teaching hospital on 2080 patients. Univariate and multivariate analyses were performed to identify the risk factors. RESULTS: The common fishbone locations were the tonsils (39.8%; defined as STEP-I), tongue base (37.1%), vallecula (13.3%; STEP-II), and hypopharynx (9.8%; STEP-III). With increasing STEP level, the ratio of difficult fishbones correspondingly increased (Z = 13.919, P < .001), and the proportions were 21.1%, 41.9%, and 70% in STEP-I, II, and III, respectively. In particular, fishbones in STEP-III (vs STEP-I) had a higher risk of difficult fishbones (odds ratio [OR]: 11.573, 95% CI: 7.987-16.769). Complaints of neck pain (yes vs no), foreign body sensation (yes vs no), and shorter length of fishbones always had a lower risk of difficult fishbones (OR: 0.455, 95% CI: 0.367-0.564; OR: 0.284, 95% CI: 0.191-0.422; OR: 0.727, 95% CI: 0.622-0.85). Missing teeth (yes vs no), swallowing behavior after fishbone ingestion (yes vs no), and male patients (vs female) had a higher risk of difficult fishbones (OR: 1.9, 95% CI: 1.47-2.456; OR: 1.631, 95% CI: 1.293-2.059; OR: 1.278, 95% CI: 1.047-1.56). CONCLUSIONS: Neck pain, foreign body sensation, fishbone length, patient age and sex, tooth status, and swallowing behavior after fishbone ingestion are independent risk factors for difficult fishbones.

Modulation of physicochemical stability and bioaccessibility of ß-carotene using alginate beads and emulsion stabilized by scallop (Patinopecten yessoensis) gonad protein isolates.

The colloidal delivery systems fabricated by emulsion containing natural proteins and lipids have been utilized to protect carotenoids as well as to release the carotenoids in the simulated in vitro gastrointestinal tract (GIT). In this study, ß-carotene (BC) was embedded into emulsions that were stabilized by scallop gonad protein isolates (SGPIs), and the emulsion droplets containing BC were then entrapped into calcium-alginate beads. The results showed that the oil-in-water emulsions coated by SGPIs only showed good stability at pH 7-8, while the emulsion-alginate beads remained relatively intact at pH 3-8. BC encapsulated in emulsions was extremely unstable and prone to degradation when stored at the comparatively higher temperature (37 °C), whereas the stability of BC was greatly enhanced through incorporation into emulsion-alginate beads. The digestion rate and extent of lipid droplets constructed within SGPIs-stabilized emulsion-alginate beads were slower than that in emulsions during GIT. The confocal laser scanning microscopy revealed that the lipid droplets in emulsions were aggregated after exposure to the mouth and gastric phases, while the emulsion-alginate beads maintained their spherical shape after exposure to the oral and gastric phases. Moreover, the free lipid droplets in the emulsions showed a higher bioaccessibility of BC (66%) than that in the emulsion-alginate beads (38%), whereas the BC transformation was on the contrary. The findings in this study indicated that SGPIs-stabilized emulsion in alginate beads can potentially be utilized for the encapsulation and controlled release of lipophilic bioactive compounds.

Folin-Ciocalteu Assay Inspired Polyoxometalate Nanoclusters as a Renal Clearable Agent for Non-Inflammatory Photothermal Cancer Therapy.

Similar to translated thermal ablative techniques in clinic, the occurrence of cellular necrosis during tumor photothermal therapy (PTT) would induce inflammatory responses that are detrimental to therapeutic outcomes. Inspired by the well-known colorimetric Folin-Ciocalteu assay, monodispersed and renal-clearable tungsten (W)-based polyoxometalate nanoclusters (W-POM NCs, average diameter of around 2.0 nm) were successfully obtained here through a facile redox reaction with natural gallic acid in alkaline aqueous solution. Apart from excellent stability in the form of freeze-dried powder, the as-prepared W-POM NCs occupied considerable biocompatibility toward normal cells/tissues both in vitro and in vivo, since no obvious toxicities were observed by treating female Balb/c mice with concentrated W-POM NCs during the 30 day post-treatment period. More importantly, W-POM NCs exhibited not only considerable near-infrared (NIR) light absorption (coloration effect originated from the existence of electron-trapped W5+) for efficient PTT but also impressive anti-inflammatory ability (eliminating inflammation-related reactive oxygen species by the oxidation of W5+ into W6+ state) to achieve better therapeutic outcomes. Thus, our study pioneers the application of POMs for non-inflammatory PTT with expected safety and efficiency.

Fabrication of surface-active antioxidant biopolymers by using a grafted scallop (Patinopecten yessoensis) gonad protein isolate-epigallocatechin gallate (EGCG) conjugate: improving the stability of tuna oil-loaded emulsions.

The oxidation of unsaturated fats generally occurs at the oil-water interface of emulsions, so surface-active antioxidants are needed for inhibiting lipid oxidation. In this study, a scallop gonad protein isolate (SGPI)-epigallocatechin gallate (EGCG) conjugate was fabricated and characterized as an amphiphilic surface-active antioxidant in improving the physicochemical and oxidative stability of tuna oil-loaded emulsions via a free-radical grafting method. The covalent binding of EGCG to SGPIs was verified by using electrophoresis and gel permeation chromatography. Meanwhile, the structural, physical, thermal, as well as the in vitro antioxidant properties of the SGPI-EGCG conjugate were further characterized. The results indicated that the SGPI-EGCG conjugate contained more ß-sheet but less α-helix than SGPIs, leading to the changes of the secondary and tertiary conformation stability after conjugation. The radical scavenging and oxygen radical absorbance capacity of SGPIs were significantly increased by 4.9 times and 7.4 times, respectively, after the EGCG-grafting reaction. Compared with that stabilized by SGPIs, tuna oil emulsions emulsified by the SGPI-EGCG conjugate exhibited a smaller particle size and better storage stability. Furthermore, the SGPI-EGCG conjugate inhibited lipid and fatty acid oxidation during storage more significantly in tuna oil emulsions than SGPIs due to its higher interfacial accumulation and antioxidant activities. These results suggested that the SGPI-EGCG conjugate could be utilized as an efficient surface-active antioxidant and emulsifier for the encapsulation and protection of unsaturated lipids.

Prevention of laryngeal webs through endoscopic keel placement for bilateral vocal cord lesions.

Transoral microresection for treatment of vocal cord lesions involving the anterior commissure may result in anterior glottic webs. In this study, we retrospectively reviewed 54 patients who underwent microsurgery for bilateral lesions involving the anterior commissure and categorized them into two groups. The keel placement and control groups received endoscopic keel placement and mitomycin C, respectively. During the follow-up of at least 1 year, the laryngeal web formation rate significantly decreased in the keel placement group compared with that in the control group (18.6% versus 54.5%, P < 0.05). Furthermore, the voice handicap index-10 scores for patients without web formation decreased in both the keel placement and control groups (P < 0.0001 and P < 0.001, respectively). A pseudomembrane covering the vocal cords was detected in 16.3% (7 of 43) cases after keel removal. A total of 100% (7 of 7) of these cases and 2.8% (1 of 36) of the other cases formed laryngeal webs (P < 0.0001). Endoscopic keel placement could be an effective method for preventing anterior glottic webs after surgery for bilateral vocal cord diseases involving the anterior commissure. The pseudomembrane observed at the time of keel removal may imply a high risk of web formation.

Long-term observation of indirect lymphography using gadolinium-loaded polyethylenimine-entrapped gold nanoparticles as a dual mode CT/MR contrast agent for rabbit lingual sentinel lymph node identification.

CONCLUSIONS: The rabbit lingual sentinel lymph node (SLN) could be long-term visualized by indirect lymphography using gadolinium-loaded polyethylenimine-entrapped gold nanoparticles (Gd-Au PENPs) as CT/MR dual-modal contrast agent. OBJECTIVE: To investigate duration and intensity of rabbit lingual SLN enhancement using Gd-Au PENPs as a CT/MR dual-modal contrast agent. METHODS: Twelve rabbits were randomly divided into indirect CT lymphography (CT-LG) and MR lymphography (MR-LG) groups. In each group, two rabbits received unilateral injection and four received bilateral injection of Gd-Au PENPs in the sub-mucosa of the tongue. Then the enhancement characteristics of SLN were investigated. RESULTS: The enhanced SLNs were observed in 100% in all rabbits by indirect CT-LG and MR-LG simultaneously at 1 min after injection. Then SLN enhancement was improved rapidly and the first peaks were observed at 25 min for CT-LG and 1 h for MR-LG, respectively, then SLN enhancement decreased gradually to a minimum at 2 h for CT-LG and 3 h for MR-LG. Afterwards, the enhancement intensity increased again and second peaks were observed at 24 h for both CT-LG and MR-LG. Hereafter, the intensity dropped slowly and weak enhancement was also observed at the 40th week for CT-LG and 31st day for MR-LG. Black-stained SLNs were visualized in 100% at autopsy in all rabbits.

Directed neurite growth of rat dorsal root ganglion neurons and increased colocalization with Schwann cells on aligned poly(methyl methacrylate) electrospun nanofibers.

Electrospun nanofibers are promising scaffolds for peripheral and central nervous system repair. The aim of this study was to examine the details of neurite growth of rat dorsal root ganglion neurons (DRGn) on randomly oriented and aligned poly(methyl methacrylate) (PMMA) nanofibers and the relationship between neurites and nanofibers on each substrate. Our substrate design involved electrospinning PMMA nanofibers directly onto bare glass coverslips with acceptable biocompatibility. We cocultured DRGn and Schwann cells on PMMA nanofibers and evaluated their response to each substrate. Compared with neurons cultured on PMMA film and randomly oriented nanofibers, DRGn on aligned PMMA nanofibers formed longer, parallel neurites in accordance with the orientation of the substrate nanofibers, although the average neurite number did not differ among the three groups. Regarding the relationship between neurites and nanofibers, the neurites of DRGn were in close contact with the substrate nanofibers, and the neurites seemed to follow aligned nanofibers more than randomly oriented nanofibers. Coculturing DRGn and Schwann cells on PMMA nanofibers revealed that on aligned nanofibers, neurites and Schwann cells had a higher chance of colocalization than on randomly oriented nanofibers or film; this colocalization may be beneficial during the process of myelination that follows. The results of this study enhance our understanding of the ability of aligned electrospun nanofibers to provide contact guidance to neural cells and strengthen the rationale for future in vivo studies.

Suturing silastic sheet from outside into larynx cavity: measurement of angles and clinical practice.

CONCLUSION: Extra-endolaryngeal cavity puncturing with reasonable puncturing angles is an alternative method for implantation of silastic sheets when the Lichtenberger needle holder is unavailable. OBJECTIVES: To determine reasonable extra-endolaryngeal puncturing angles for implantation of laryngeal silastic sheet and to observe the effect on treating and preventing glottic webs. METHODS: Puncture processes were conducted via extra-endolaryngeal access. For the upper puncture, the needle was inserted into the bottom of the epiglottic petiole superior to the anterior commissure through the thyrohyoid membrane. For the lower puncture, the needle was delivered into the inferior to anterior commissure (equivalent to the inferior border of the vocal cords) through the cricothyroid membrane. The upper and lower puncture angles between puncture needles and the tangential line of the thyroid cartilage were measured in 14 cadavers. Silastic sheets were implanted into laryngeal cavities in 20 patients to treat or prevent anterior glottic webs. RESULTS: The mean value of the upper puncture angle was 30° (range 23.5-39°) while the lower puncture angle was also 30° (24-40°). Surgery procedures for implanting silastic sheets succeeded in 20 patients by extra-endolaryngeal puncture access. The average numbers of upper and lower punctures were 2 and 1.6, respectively. At follow-up none of the 20 patients had webs or had only 1 mm adhesion area.