Tracking and imaging nano-plastics in fresh plant using cryogenic laser ablation inductively coupled plasma mass spectrometry.

Tracking and imaging of nano-plastics are extremely challenging, especially in fresh biological samples. Here, we propose a new strategy in which polystyrene (PS) was doped with the europium chelate Eu (DBM)3bpy to quantify, track, and in situ image nano-plastics in fresh cucumber based on inherent metals using cryogenic laser ablation inductively coupled plasma mass spectrometry (cryo-LA-ICP-MS). The cryogenic conditions provide a stable condition for imaging fresh cucumber, suppressing the evaporation of water in fresh plants, and maintaining the original structure of plants with respect to room temperature imaging in LA-ICP-MS. The plants were cultivated in two types of nano-plastics solutions with low (50 mg/L) and high (200 mg/L) concentrations for 9 days. The results showed that nano-plastics mainly enrich the roots and have negative effects, which decrease the trace elements of Zn, Mn, and Cu in cucumber. Smaller PS particles are able to penetrate the plant more easily and inflict serious damage. Novel imaging method provides a novel insight into the tracking and imaging of nano-plastics in fresh plant samples. The results illustrated that nano-plastics deposition on plants has the potential to have direct ecological effects as well as consequences for potential health.

A new assisted fixation technique to prevent zygoma displacement in malar reduction.

BACKGROUND: Reduction malarplasty via an intraoral approach for correction of a prominent malar complex is quite popular in the Orient. However, one point of fixation in the anterior zygoma body area, the most widely used method, sometimes is insufficient and likely to result in malunion and cheek drooping. We designed a new assisted fixation technique to strengthen the effect of fixation. METHODS: Two parallel oblique vertical ostectomies were performed on the zygomatic body with a groove left in the inner osteotomy line. The zygomatic arch root was cut obliquely through a small sideburn incision just in front of articular tubercle, medial to lateral and anterior to posterior. The freed malar complex was medially and superiorly repositioned with the zygomatic body wedged in the groove, followed by fixation with one miniplate or wire. Finally, the periosteum in the zygomatic area was pulled and sutured to the deep temporal fascia. RESULTS: Most patients were satisfied with their results. No inferiorly displaced malunion occurred in the zygomatic body. There were no serious complications such as nonunion or permanent facial nerve injury. Minor complications, including palpable step-off, mild asymmetry, hematoma, and mild cheek drooping, occurred in some cases. CONCLUSION: Our assisted fixation method, combined with subperiosteal lifting, can provide ideal effects and sufficient fixation in malar reduction to prevent many complications such as malunion and cheek drooping. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Insulin-like growth factor-2 antisense oligonucleotides inhibits myopia by expression blocking of retinal insulin-like growth factor-2 in guinea pig.

OBJECTIVE: To clarify the role of IGF-2 on the development of myopia, the dynamic expression of IGF-2 was investigated in the FD eyes' retina, and the effects of intravitreous injection with IGF-2 ASON was studied on the diopter and axial eye length of FD eyes. METHODS: 64 guinea pigs were divided into 2 groups. In group A (n = 24), the right eyes were covered. On days 7, 14 and 21, the diopter, axial eye length and level of IGF-2 of both eyes were measured in every 8 guinea pigs. In group B (n = 40), the right eyes were covered. On day 1, the right eyes were received intravitreal injection with 40 µg IGF-2SON, 10 µg, 20 µg or 40 µg IGF-2 ASON. The diopter, axial eye length and level of IGF-2 were measured on day 14. RESULTS: FD eyes showed myopic shift, axial length enlongation, and up-regulation in retinal IGF-2 from day 7 to day 21. The level of retinal IGF-2 in FD eyes was higher than that in non-FD eyes. Compare with FD eyes without injection, the myopia diopter of FD eyes decreased in received intravitreous injection with IGF-2 ASON, axial length shortened, and down-regulated with retinal IGF-2. With the increase dose of IGF-2 ASON, the change of myopic diopter, axial length, and level of retinal IGF-2 were showed more and more significant. CONCLUSIONS: FD is effective to up-regulate the level of retinal IGF-2 expression in guinea pig. Intravitreous injection with IGF-2 ASON can inhibit the development of myopia.

Wright's Technique with the Addition of Visualized Axial Cortical Windows in Odontoid Fractures.

This study sought to investigate and evaluate a modified axial translaminar screw fixation for treating odontoid fractures. We performed a retrospective study at Wenzhou Medical University Affiliated Second Hospital between March 2016 and June 2018. We retrospectively collected and analyzed the medical records of 23 cases with odontoid fractures. All patients were identified as type II odontoid fractures without neurological deficiency and serious diseases following the classification of Anderson. The average age, gender ratio, and body mass index (BMI) were 54.3 ± 11.1 years, 12 men to 11 women, and 22.6 ± 2.4 kg/m2 , respectively. Patients in this study accepted screw fixation using our modified axial translaminar screw fixation combined with atlas pedicle or lateral mass screw fixation. Within the technique, a small cortical "window" was dug in the middle of the axial contralateral lamina, such that the screws in the lamina were visualized to prevent incorrectly implanting the posterior spinal canal through the visualized "window." A total of 46 bone screws were accurately inserted into the axial lamina without using fluoroscopy. The length of all translaminar screws ranged between 26 and 30 mm, while the diameter was 3.5 mm. During the follow-up survey, the visual analog scale (VAS) and neck disability index (NDI) were measured. We provide a simple modification of Wright's elegant technique with the addition of "visualized windows" at the middle of the axial lamina. In all patients, screws were inserted accurately without bony breach and the screw angle was 56.1 ± 3.0°. Mean operative time was 102 ± 28 min with an average blood loss of 50 ± 25 mL. Postoperative hemoglobin and mean length of hospital stay were 12.0 ± 1.4 g/dL and 10.4 ± 3.4 days, respectively. The average follow-up time of all cases was 14.7 months and no internal fixation displacement, loosening, or breakage was found. All patients with odontoid fractures reported being satisfied with the treatment during the recheck period and good clinical outcomes were observed. At 1, 6, and 12 months, NDI and VAS showed that the symptoms of neck pain and limitations of functional disability improved significantly during follow-up. Our results suggest that the modified translaminar screw fixation technique can efficiently treat Anderson type II odontoid fracture, followed by the benefits of less soft tissue dissection, simple operation, no fluoroscopy, and accurate placement of screws.

Combined long-curved ostectomy in the inferior mandibular border and angle of the mandible with splitting corticectomy for reduction of the lower face.

BACKGROUND: In Asian countries, a square-shaped face is considered unattractive. Many operative techniques have been developed and reported for reduction of the lower face, including mandibular angle ostectomy and splitting corticectomy. Many surgeons have performed the operation in the angle region using one of the aforementioned techniques, which may not lead to effective results. This report mainly discusses the standard procedures of surgery. METHODS: To overcome the drawbacks of conventional procedures and to perform ostectomy accurately, proper preoperative analysis and design were implemented for 159 patients with square-shaped faces. Based on a new type of classification and concepts for mandible reduction, long-curved ostectomy combined with splitting corticectomy was used for reduction of the lower face. A series of standard procedures was developed during the operative process. RESULTS: The majority of patients were satisfied with both their frontal and lateral appearances. The gonial angle and the mandibular plane angle were increased effectively. No major complications such as fracture or facial nerve damage occurred. Lip numbness occurred for 15% of the patients. CONCLUSIONS: The authors' series of standard procedures allows surgeons to perform accurate, safe, and reproducible ostectomy and to obtain reliable and stable effects.

Acceptable Chin-Brow Vertical Angle for Neutral Position Radiography: Preliminary Analyses Based on Parameters of the Whole Sagittal Spine of an Asymptomatic Chinese Population.

OBJECTIVE: We sought to acquire the whole sagittal spine parameters and investigated the acceptable chin-brow vertical angle (CBVA) for neutral position radiography in an asymptomatic Chinese population. METHODS: The parameters measured in 257 asymptomatic volunteers included CBVA, occipital slope, orbital tilt, occipital incidence, C0-C2 Cobb angle, C2-C7 Cobb angle, C1-C7 Cobb angle, C2-C7 sagittal vertical axis and absolute rotation angle, cervical tilt, cranial tilt, T1 slope, and thoracic kyphosis, and others. We used Pearson correlation analyses to find relationships between CBVA and other variables. The subjects were divided into 5 groups according to the CBVA percentile: group A, 0%-20% CBVA; group B, 20%-40% CBVA; group C, 40%-60% CBVA; group D, 60%-80% CBVA; and group E, 80%-100% CBVA. We used analysis of variance to analyze differences among the 5 groups. RESULTS: Orbital tilt, Occipital incidence, C1-C7 Cobb angle, C2-C7 sagittal vertical axis, and cranial tilt all increased with increasing CBVA (P < 0.001). The occipital slope, C2-C7 Cobb angle, C2-C7 absolute rotation angle, cervical tilt, T1 slope, and thoracic kyphosis decreased with decreasing CBVA (P < 0.05). No correlations between other sagittal parameters and the CBVA were found. A slight deviation was found in groups B-D, with a greater deviation in groups A, C, and E. CONCLUSIONS: An acceptable range of -1.5° to 5.8° is recommended for the CBVA for cervical radiography in the neutral position. When spinal surgeons evaluate the cervical plane, the effects of the CBVA deviation on cervical curvature must be considered.

Transplantation of osteoblast-like cells to the distracted callus in the rabbit mandible.

BACKGROUND: The purpose of this study was to investigate whether injections of marrow-derived mesenchymal progenitor cells could be used to facilitate new bone formation during distraction osteogenesis. METHODS: Fifteen New Zealand rabbits underwent bilateral osteotomy. After a 1-week latency period, bone distraction was activated at a rate of 2.0 mm/day for 5 days. The marrow-derived mesenchymal progenitor cells derived from the ilium marrow were cultured to a population of 10 in 0.5 ml and then unilaterally transplanted to the gap of distracted callus immediately after distraction had been terminated. Rabbits were killed at 2, 4, and 6 weeks after completion of bone lengthening. The distracted areas were harvested and evaluated by histologic, histomorphometric, radiographic, and scanning electron microscopic analysis. Bone mineral density in the lengthened callus was evaluated using dual-energy x-ray absorptiometry. RESULTS: Radiographic evaluation indicated a significant increase in bony union of the distraction regenerate in the experimental side compared with the control side. Corresponding to the radiographic findings, the histologic examination showed an earlier and more intensive bone formation in the experimental side after 2, 4, and 6 weeks compared with the control side. Larger chondroid islands were found evident in distracted bone of the control side than in the experimental side. CONCLUSIONS: The results show that transplantation of osteoblast-like cells promotes maturity of the distracted callus, as observed on the second and fourth weeks after lengthening. The method appears promising as a means of shortening the consolidation period of osteodistraction and decreasing complications during bone lengthening.

Distraction osteogenesis in the irradiated rabbit mandible.

PURPOSE: The potential use of distraction osteogenesis in mandibular reconstruction has been limited by its questionable efficacy in previously radiated bone. The purpose of this study was to evaluate the effects of irradiation on mandibular distraction osteogenesis (DO). MATERIALS AND METHODS: Six rabbits received a unilateral irradiation (group R) in the mandible with a total dose of 27.0 Gy in five 5.4 Gy fractions (equivalent to 50 Gy/25 fractions). The contralateral side served as control (group C). Bilateral osteotomy was made 3 months after completion of irradiation. After a 1-week latency period bone distraction was activated at a rate of 0.5 mm twice daily for 8 days, followed by a consolidation phase of 6 weeks. New bone underwent radiographic, densitometric, histological and histomorphometric analysis. RESULTS: Two rabbits were excluded from the study, one due to infection on both sides and death in another animal. After 6 weeks of consolidation, the irradiation group had no significantly lower BMD than control group. No difference was found between the percent area of new bone in both groups. New bone was more mature and organised of group C than in groups R. Larger chondroid islands were found evident in distracted bone of group R than group C. CONCLUSIONS: It seems that DO can be feasible in previously irradiated rabbit mandible.