[Digital study on proximal clavicle anatomical plate based on 3D printing technology].

OBJECTIVE: To explore feasibility of 3D metal printing technology combined with virtual design proximal clavicle anatomical plate. METHODS: A 52-year-old male healthy volunteer was retrospectively selected to design proximal clavicle anatomical plate system by using Mimics15.01,NX12.0 and other software. STL data were input into 3D printer to print 1:1 clavicle model and proximal clavicle anatomical plate. The fit of the plate was tested in vitro and the accuracy of screw position was evaluated by imaging. Printing time of model,nail path design and fabrication time of the anatomical plate at proximal clavicle were recorded. RESULTS: The 3D metal printing proximal clavicle anatomical plate fitted well to clavicle model,orientation of proximal clavicle locking screw was accurate,and X-ray and CT scan showed the screw position was good. Printing time of model,the time of nail path design,and the time of making anatomical plate of proximal clavicle were 120,15 and 300 min respectively. CONCLUSION: The proximal clavicular anatomical plate system based on 3D metal printing technology could achieve good lamination of proximal clavicular fracture plate and precise screw placement,providing a new and accurate surgical method for the treatment of the proximal clavicular fracture.

Preoperative simulated surgery on 3D model assists osteotomy feasibility verification and surgical guidance for patients with cubitus valgus/varus deformity: a retrospective observational study.

BACKGROUND: As the common delayed complication of supracondylar fractures in children, cubitus valgus/varus deformity might lead to pain and loss of motion of the elbow. The current corrective treatment might not be accurate enough and even contribute to postoperative deformity. This study retrospectively analyzed the clinical value of preoperative simulated surgery on 3D model-assisted osteotomy feasibility verification and surgical guidance for cubitus valgus/varus deformity. METHODS: Seventeen patients were selected from October 2016 to November 2019. Deformities were analyzed from imaging data and 3D models and corrected after the simulated operations. The radiographic evaluation comprised osseous union, carrying angle, and anteversion angle of the distal humerus. The clinical evaluation was performed according to the Hospital for Special Surgery (HSS) scoring system. RESULTS: All patients underwent the operation successfully and had no postoperative deformity. The carrying angle was significantly improved postoperatively (P < 0.001). The anteversion angle of the distal humerus did not change significantly (P > 0.05). The HSS score rose after surgery (P < 0.001). The function of the elbow joint was excellent in seven cases and good in ten cases. CONCLUSION: Simulated surgery on 3D model plays an important role in osteotomy plan and surgical guidance, contributing to good surgical efficacy.

Triple Endobutton technique for the treatment of Neer type II lateral clavicle fractures: 2-year findings.

BACKGROUND: Although various kinds of operative procedures have been reported in the literature, there is still no undisputed gold standard technique for the treatment of Neer type II lateral clavicle fractures. This trauma is classified as a bone fracture, but it is primarily a ligamentous problem due to the instability it generates. This study analyzed the clinical and radiological results of treatment for Neer type II lateral clavicle fractures using the triple Endobutton (Smith & Nephew) technique in 20 patients with at least 2 years of follow-up. METHODS: This study enrolled 20 patients with Neer type II distal clavicle fractures who underwent the triple Endobutton technique using 3 Endobuttons (1 with a closed loop and 2 without) and 3 No. 5 Ethibond sutures (Ethicon Inc.) from October 2017 to May 2020. Patients were assessed with clinical and radiological follow-up at 3, 6, 12, and 24 months postoperatively. Clinical assessments consisted of the visual analog scale and the Constant score. Radiological evaluation was achieved by measuring the coracoclavicular distance. RESULTS: The mean follow-up was 35 ± 9 months (range, 24-55 months). The visual analog scale and Constant scores revealed significant improvements from 6 ± 1 (range, 4-8) and 42 ± 4 (range, 35-48) scores preoperatively to 1 ± 1 (range, 0-1) and 94 ± 2 (range, 90-98) scores at the final evaluation, respectively (P < .001). The coracoclavicular distance of the injured side was an average of 9 ± 1 mm (range, 7-12 mm) at the final follow-up radiograph which was not significantly different from that of the contralateral side (P = .75). CONCLUSIONS: In this study, the triple Endobutton technique was a safe, reliable, and novel surgical technique that yielded good to excellent short-term clinical and radiological outcomes for the treatment of Neer type II distal clavicle fractures.

Terahertz hybrid optical-plasmonic modes: tunable resonant frequency, narrow linewidth, and strong local field enhancement.

Hybrid optical-plasmonic modes have the characteristics of low loss and small mode volume, which will result in the strong localization and enhancement of electromagnetic field. Such advantages of hybrid optical-plasmonic mode are important for the enhancement of light-matter interactions. Here, terahertz (THz) hybrid modes of Fabry-Perot resonances (FPRs) and spoof surface plasmon polaritons (SSPPs) in the modified Otto scheme are investigated both in theoretical and experimental aspects. The device structure is composed of a metal grating silicon waveguide (MGSW) and a metal slit grating (MSG). The two components are vertically stacked with a variable air gap between them. The THz hybrid modes are originated from the far-field coupling of the FPRs and the SSPP supported by the air gap and the MSG, respectively. By changing the thickness of the air gap, the resonant frequency of the FPR-SSPP modes can be tuned in a frequency range of about 0.1 THz. An anti-crossing behavior between two reflection dips corresponding to the guided-mode resonance in the MGSW and the FPR-SSPP mode is observed, which leads to the narrowing of the reflection dips in the anti-crossing region. Numerical simulations show that at the resonant frequencies of FPR-SSPP mode, there is a huge volume-averaged electromagnetic energy enhancement of about 1600 times in the grooves of the MSG, which is around 8.7 times larger than that induced by the SSPP directly launched by free-space electromagnetic field. The hybrid FPR-SSPP modes can be used to construct THz sensors and detectors with high sensitivity.

Truly anatomic coracoclavicular ligament reconstruction with 2 EndoButton devices for acute Rockwood type V acromioclavicular joint dislocations: 5-year findings.

BACKGROUND: To date, mid-term clinical and radiologic outcomes of treatment for acute Rockwood type V acromioclavicular (AC) joint dislocations using 2 EndoButton devices (Smith & Nephew, Andover, MA, USA) have not been reported in the literature. METHODS: We reviewed 25 patients (15 men and 10 women) with acute AC joint separations who were treated with truly anatomic coracoclavicular ligament reconstruction using 2 EndoButton devices between May 2013 and October 2015. Clinical assessments consisted of the visual analog scale score and the Constant score. Radiologic evaluation was achieved by measuring the coracoclavicular distance and AC distance. Previously, this same patient cohort was reviewed after 2 years of follow-up using similar methods. RESULTS: All 25 patients were available for mid-term follow-up 5 years after the operation. The mean duration of follow-up was 76 ± 7 months (range, 66-90 months). Of the patients, 23 (92%) continued to be satisfied or very satisfied with the treatment results. The visual analog scale score and Constant score improved significantly when compared with the baseline scores (0 ± 0 and 96 ± 3, respectively, at 5-year follow-up vs. 5 ± 1 and 45 ± 6, respectively, postoperatively) and remained essentially unchanged when compared with the 2-year follow-up data (0 ± 0 and 96 ± 3, respectively, at 5-year follow-up vs. 0 ± 1 and 95 ± 3, respectively, at 2-year follow-up). On the 5-year radiographs, 3 patients (12%) demonstrated loss of reduction and 5 patients (20%) had calcifications noted. There was, however, no significant difference in clinical outcomes or patient satisfaction when comparing patients with radiographically abnormal findings vs. patients with anatomic reduction. CONCLUSION: Truly anatomic coracoclavicular ligament reconstruction using 2 EndoButton devices results in satisfactory functional outcomes at 5 years postoperatively. In contrast to baseline, all cases improved significantly.

DEAD-box helicases modulate dicing body formation in Arabidopsis.

Eukaryotic cells contain numerous membraneless organelles that are made from liquid droplets of proteins and nucleic acids and that provide spatiotemporal control of various cellular processes. However, the molecular mechanisms underlying the formation and rapid stress-induced alterations of these organelles are relatively uncharacterized. Here, we investigated the roles of DEAD-box helicases in the formation and alteration of membraneless nuclear dicing bodies (D-bodies) in Arabidopsis thaliana We uncovered that RNA helicase 6 (RH6), RH8, and RH12 are previously unidentified D-body components. These helicases interact with and promote the phase separation of SERRATE, a key component of D-bodies, and drive the formation of D-bodies through liquid-liquid phase separations (LLPSs). The accumulation of these helicases in the nuclei decreases upon Turnip mosaic virus infections, which couples with the decrease of D-bodies. Our results thus reveal the key roles of RH6, RH8, and RH12 in modulating D-body formation via LLPSs.

[Meta-analysis of direct anterior approach and other approaches for hemiarthroplasty in elderly patients with femoral neck fracture].

OBJECTIVE: To systematically evaluate the clinical efficacy of high-quality direct anterior approach (DAA) and other approaches for the treatment of elderly patients with femoral neck fracture. METHODS: Literatures published in English or Chinese about the direct anterior approach and other approaches for hemiarthroplasty in femoral neck fracture were searched on Cochrane Library, PubMed, EMBASE, Web of science, Wanfang, CNKI databases from their establishment to May 2019. According to the inclusion and exclusion criteria, two researchers independently screened the literatures, and extracted the data. The quality of RCT were evaluated by Cochrane Risk of Bias Assessment Tool, and non-RCT were evaluated by the NOS scale. Meta-analysis was performed using the RevMan 5.3 software. RESULTS: A total of 9 articles were included with 901 cases, in which 429 cases used DAA, and 472 used other approaches. DAA had a significantly lower dislocation rate compared to subgroup of posterior and posterolateral approach [OR=0.19, 95%CI (0.06, 0.61), P=0.005]. No significant differences were found between DAA group and subgroup of direct lateral and anterolateral approach[OR=1.08, 95%CI(0.20, 5.76), P=0.93]. Also there were no relevant differences between the DAA group and control in infection rate[OR=1.07, 95%CI(0.47, 2.43), P=0.88], perioperative fracture rate[OR=0.95, 95%CI(0.36, 2.50), P=0.92], re operation rate[OR=0.76, 95%CI(0.30, 1.89), P=0.55], overall complication rate [OR=0.88, 95%CI (0.63, 1.22), P=0.44], mortality [OR=1.33, 95%CI (0.84, 2.11), P=0.23], operative time[MD=1.43, 95%CI(-5.85, 8.71), P=0.70]. CONCLUSION: The current evidenceindicates that the DAA was associated with a significantly lower dislocation rate compared to posterior capsular approaches for hemiarthroplasty. There was no significant difference in dislocation rate with the lateral and anterolateral approach.

Antiviral ARGONAUTEs Against Turnip Crinkle Virus Revealed by Image-Based Trait Analysis.

RNA-based silencing functions as an important antiviral immunity mechanism in plants. Plant viruses evolved to encode viral suppressors of RNA silencing (VSRs) that interfere with the function of key components in the silencing pathway. As effectors in the RNA silencing pathway, ARGONAUTE (AGO) proteins are targeted by some VSRs, such as that encoded by Turnip crinkle virus (TCV). A VSR-deficient TCV mutant was used to identify AGO proteins with antiviral activities during infection. A quantitative phenotyping protocol using an image-based color trait analysis pipeline on the PlantCV platform, with temporal red, green, and blue imaging and a computational segmentation algorithm, was used to measure plant disease after TCV inoculation. This process captured and analyzed growth and leaf color of Arabidopsis (Arabidopsis thaliana) plants in response to virus infection over time. By combining this quantitative phenotypic data with molecular assays to detect local and systemic virus accumulation, AGO2, AGO3, and AGO7 were shown to play antiviral roles during TCV infection. In leaves, AGO2 and AGO7 functioned as prominent nonadditive, anti-TCV effectors, whereas AGO3 played a minor role. Other AGOs were required to protect inflorescence tissues against TCV. Overall, these results indicate that distinct AGO proteins have specialized, modular roles in antiviral defense across different tissues, and demonstrate the effectiveness of image-based phenotyping to quantify disease progression.

MicroRNA-221 promotes cell proliferation, migration, and differentiation by regulation of ZFPM2 in osteoblasts.

Bone fracture is a common medical condition, which may occur due to traumatic injury or disease-related conditions. Evidence suggests that microRNAs (miRNAs) can regulate osteoblast differentiation and function. In this study, we explored the effects and mechanism of miR-221 on the growth and migration of osteoblasts using MC3T3-E1 cells. The expression levels of miR-221 in the different groups were measured by qRT-PCR. Then, miR-221 mimic and inhibitor were transfected into MC3T3-E1 cells, and cell viability and migration were measured using the CCK-8 assay and the Transwell migration assay. Additionally, the expression levels of differentiation-related factors (Runx2 and Ocn) and ZFPM2 were measured by qRT-PCR. Western blot was used to measure the expression of cell cycle-related proteins, epithelial-mesenchymal transition (EMT)-related proteins, ZFPM2, and Wnt/Notch, and Smad signaling pathway proteins. miR-221 was significantly up-regulated in the patients with lumbar compression fracture (LCM) and trochanteric fracture (TF). miR-221 promoted ALP, Runx2, and OPN expressions in MC3T3-E1 cells. miR-221 overexpression significantly increased cell proliferation, migration, differentiation, and matrix mineralization, whereas suppression of miR-221 reversed these effects. Additionally, the results displayed that ZFPM2 was a direct target gene of miR-221, and overexpression of ZFPM2 reversed the promoting effects of miR-221 overexpression on osteoblasts. Mechanistic study revealed that overexpression of miR-221 inactivated the Wnt/Notch and Smad signaling pathways by regulating ZFPM2 expression. We drew the conclusions that miR-221 overexpression promoted osteoblast proliferation, migration, and differentiation by regulation of ZFPM2 expression and deactivating the Wnt/Notch and Smad signaling pathways.

MicroRNA-221 promotes cell proliferation, migration, and differentiation by regulation of ZFPM2 in osteoblasts

Bone fracture is a common medical condition, which may occur due to traumatic injury or disease-related conditions. Evidence suggests that microRNAs (miRNAs) can regulate osteoblast differentiation and function. In this study, we explored the effects and mechanism of miR-221 on the growth and migration of osteoblasts using MC3T3-E1 cells. The expression levels of miR-221 in the different groups were measured by qRT-PCR. Then, miR-221 mimic and inhibitor were transfected into MC3T3-E1 cells, and cell viability and migration were measured using the CCK-8 assay and the Transwell migration assay. Additionally, the expression levels of differentiation-related factors (Runx2 and Ocn) and ZFPM2 were measured by qRT-PCR. Western blot was used to measure the expression of cell cycle-related proteins, epithelial-mesenchymal transition (EMT)-related proteins, ZFPM2, and Wnt/Notch, and Smad signaling pathway proteins. miR-221 was significantly up-regulated in the patients with lumbar compression fracture (LCM) and trochanteric fracture (TF). miR-221 promoted ALP, Runx2, and OPN expressions in MC3T3-E1 cells. miR-221 overexpression significantly increased cell proliferation, migration, differentiation, and matrix mineralization, whereas suppression of miR-221 reversed these effects. Additionally, the results displayed that ZFPM2 was a direct target gene of miR-221, and overexpression of ZFPM2 reversed the promoting effects of miR-221 overexpression on osteoblasts. Mechanistic study revealed that overexpression of miR-221 inactivated the Wnt/Notch and Smad signaling pathways by regulating ZFPM2 expression. We drew the conclusions that miR-221 overexpression promoted osteoblast proliferation, migration, and differentiation by regulation of ZFPM2 expression and deactivating the Wnt/Notch and Smad signaling pathways.

The Drosophila Postsynaptic DEG/ENaC Channel ppk29 Contributes to Excitatory Neurotransmission.

The protein family of degenerin/epithelial sodium channels (DEG/ENaCs) is composed of diverse animal-specific, non-voltage-gated ion channels that play important roles in regulating cationic gradients across epithelial barriers. Some family members are also enriched in neural tissues in both vertebrates and invertebrates. However, the specific neurophysiological functions of most DEG/ENaC-encoding genes remain poorly understood. The fruit fly Drosophila melanogaster is an excellent model for deciphering the functions of DEG/ENaC genes because its genome encodes an exceptionally large number of DEG/ENaC subunits termed pickpocket (ppk) 1-31 Here we demonstrate that ppk29 contributes specifically to the postsynaptic modulation of excitatory synaptic transmission at the larval neuromuscular junction. Electrophysiological data indicate that the function of ppk29 in muscle is necessary for normal postsynaptic responsivity to neurotransmitter release and for normal coordinated larval movement. The ppk29 mutation does not affect gross synaptic morphology and ultrastructure, which indicates that the observed phenotypes are likely due to defects in glutamate receptor function. Together, our data indicate that DEG/ENaC ion channels play a fundamental role in the postsynaptic regulation of excitatory neurotransmission.SIGNIFICANCE STATEMENT Members of the degenerin/epithelial sodium channel (DEG/ENaC) family are broadly expressed in epithelial and neuronal tissues. To date, the neurophysiological functions of most family members remain unknown. Here, by using the power of Drosophila genetics in combination with electrophysiological and behavioral approaches, we demonstrate that the DEG/ENaC-encoding gene pickpocket 29 contributes to baseline neurotransmission, possibly via the modulation of postsynaptic glutamate receptor functionality.

Natural antisense transcripts regulate the neuronal stress response and excitability.

Neurons regulate ionic fluxes across their plasma membrane to maintain their excitable properties under varying environmental conditions. However, the mechanisms that regulate ion channels abundance remain poorly understood. Here we show that pickpocket 29 (ppk29), a gene that encodes a Drosophila degenerin/epithelial sodium channel (DEG/ENaC), regulates neuronal excitability via a protein-independent mechanism. We demonstrate that the mRNA 3'UTR of ppk29 affects neuronal firing rates and associated heat-induced seizures by acting as a natural antisense transcript (NAT) that regulates the neuronal mRNA levels of seizure (sei), the Drosophila homolog of the human Ether-à-go-go Related Gene (hERG) potassium channel. We find that the regulatory impact of ppk29 mRNA on sei is independent of the sodium channel it encodes. Thus, our studies reveal a novel mRNA dependent mechanism for the regulation of neuronal excitability that is independent of protein-coding capacity. DOI: http://dx.doi.org/10.7554/eLife.01849.001.

A permissive role of mushroom body α/ß core neurons in long-term memory consolidation in Drosophila.

BACKGROUND: Memories are not created equally strong or persistent for different experiences. In Drosophila, induction of long-term memory (LTM) for aversive olfactory conditioning requires ten spaced repetitive training trials, whereas a single trial is sufficient for LTM generation in appetitive olfactory conditioning. Although, with the ease of genetic manipulation, many genes and brain structures have been related to LTM formation, it is still an important task to identify new components and reveal the mechanisms underlying LTM regulation. RESULTS: Here we show that single-trial induction of LTM can also be achieved for aversive olfactory conditioning through inhibition of highwire (hiw)-encoded E3 ubiquitin ligase activity or activation of its targeted proteins in a cluster of neurons, localized within the α/ß core region of the mushroom body. Moreover, the synaptic output of these neurons is critical within a limited posttraining interval for permitting consolidation of both aversive and appetitive LTM. CONCLUSIONS: We propose that these α/ß core neurons serve as a "gate" to keep LTM from being formed, whereas any experience capable of "opening" the gate is given permit to be consolidated into LTM.

ben Functions with scamp during synaptic transmission and long-term memory formation in Drosophila.

Genetic screens for Drosophila mutants defective in pavlovian olfactory memory have provided unique insight into the molecular basis of memory storage. Occasionally, these singular genetic lesions have been assembled into meaningful molecular pathways and neural circuitries. For the most part, however, these genes and their expression patterns in the CNS remain fragmented, demanding new clues from continued mutant screens. From a behavioral screen for long-term memory (LTM) mutants, we have identified ben (CG32594), which encodes a novel protein. Mutations of ben specifically disrupt LTM, leaving earlier memory phases intact. The role of ben appears physiological rather than developmental, because acutely induced expression of a ben(+) transgene in adults rescues the mutant's LTM defect. More interestingly, induced expression of ben(+) specifically in mushroom bodies (MBs), but not in the ellipsoid body of the central complex, is sufficient to rescue the mutant LTM defect. This suggests a role for ben in the MB during olfactory memory formation. We also provide evidence that BEN interacts genetically in both synaptic transmission and LTM formation with SCAMP, a synaptic protein known to be involved in vesicle recycling.