Research progress of microRNA in spinal cord injury.

Spinal cord injury (SCI) is a serious central nervous system disease with high disability and mortality rates and complex pathophysiologic mechanisms. MicroRNA (miRNA), as a kind of non-coding RNA, plays an important role in SCI. miRNA is involved in the regulation of inflammatory response, oxidative stress, axonal regeneration, and apoptosis after SCI, and interacts with long non-coding RNA (lncRNA) and circular RNA (circRNA) to regulate the pathophysiological process of SCI. This paper summarizes the changes in miRNA expression after SCI, and reviews the targeting mechanism of miRNA in SCI and the current research status of miRNA-targeted drugs to provide new targets and new horizons for basic and clinical research on SCI.

A Modified Algorithm-Based Levator Aponeurectomy in Mild to Moderate Congenital Blepharoptosis.

BACKGROUND: Levator aponeurectomy is a common operation for mild to moderate blepharoptosis. The accuracy of ptosis correction relied on intraoperative judgement when patients were under local anesthesia. For patients who must receive the operation under general anesthesia, it would be an issue to determine how much length of levator aponeurosis to shorten. To solve this issue, we collected data from patients who underwent the operation under local anesthesia and concluded an algorithm. METHODS: This single-center, prospective bivariate regression study allocated patients of mild to moderate congenital blepharoptosis who received levator aponeurectomy under local anesthesia. Preoperative MRD1 and levator function, intraoperative amount of levator aponeurotic shortening, and postoperative MRD1 were measured. The follow-up period was right after the operation. RESULTS: Twenty-nine patients were included in this trial. Two subjects exited because of not receiving allocated operation and data of the other 27 subjects (including 34 eyelids) were analyzed. A scatter diagram was drawn where x axis referred to levator function and y axis referred to the ratio of the amount of shortening of levator aponeurosis over the height of MRD1 correction. Linear regression showed y = - 0.2717*x + 5.026, R2 = 0.8553. CONCLUSION: A modified algorithm to predict the amount of shortening of levator aponeurosis based on levator function and height of ptosis correction was concluded with better accuracy and clinical feasibility. 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 .

The Pendulum Movement of Orbital Fat and Retro-Orbicularis Oculi Fat: A New Strategy for Correction of Sunken Eyelid Deformity in Revision Upper Blepharoplasty for Asian Patients.

BACKGROUND: With an increasing number of East Asians undergoing blepharoplasty, the number of patients with secondary upper eyelid deformities is increasing. The sunken eyelid deformity is a common deformity after upper blepharoplasty in Asians due to over-resection, retraction, or atrophy of the nasal and central orbital fat pads. Herein, we present a novel procedure, the pendulum movement of orbital fat and retro-orbicularis oculi fat ("POR" technique), for correction of sunken eyelid deformity in secondary Asian blepharoplasty. METHODS: Patients who underwent secondary upper blepharoplasty with the POR technique by the senior author between January 2020 and October 2021 were identified retrospectively. Those with fewer than 6 months of follow-up were excluded. Patient charts and images were reviewed for demographic data, comorbidities, concomitant eyelid deformities, and postoperative complications. Pre- and postoperative aesthetics, including degree of sunken eyelid deformity, were assessed by two independent raters and by self-reported patient satisfaction. RESULTS: Forty-nine consecutive patients were identified, all of whom were female and had grade I or II sunken eyelid deformity. Median follow-up was 8 months. Concomitant deformities included high tarsal crease (N = 31 patients, 63.3%), ptosis (N = 13, 26.5%), and upper eyelid retraction (N = 5, 10.2%). Almost patients had improvement in their eyelid volume, and 95.9% had improvement in their aesthetic rating. Approximately 93.9% of patients were satisfied with the outcome. CONCLUSIONS: The POR technique is an effective technique for correction of sunken eyelid deformity and can be utilized in conjunction with other techniques during secondary blepharoplasty. LEVEL OF EVIDENCE III: 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 .

Knockdown of ZEB1 Inhibits Hypertrophic Scarring through Suppressing the Wnt/ß-catenin Signaling Pathway in a Mouse Model.

BACKGROUND: Hypertrophic scars (HS) cause functional impairment and cosmetic deformities following surgeries or burns (30% to 94%). There is no target therapy yet because the pathogenesis of HS progression is not well-known. In tissue fibrosis, Zinc finger E-box binding homeobox 1 (ZEB1) abnormal upregulation is an important cause for extracellular matrix (ECM) overexpression, which is the main molecular change in HS. Therefore, we hypothesized that ZEB1-knockdown inhibits HS formation. METHODS: ZEB1 expression in human HS and TGF-ß1-induced fibroblasts were identified by PCR and western blotting. ZEB1 was knockdown by siRNA in HS fibroblasts (HSFs) and mouse HS model (C57/BL6, male, 8-12 weeks). After 8-hour-transfection, HSFs were subjected to PCR, western blotting and CCK-8, apoptosis, migration and contraction assays. Mice HS were analyzed by HE staining, PCR and western blotting after 56 days. RESULTS: ZEB1 was upregulated in HS tissue (2.0-fold; p < 0.001). ZEB1 knockdown inhibited HSFs activity (0.6 to 0.7-fold; p < 0.001), the expression of fibrotic markers (0.4 to 0.6-fold; p < 0.001) and ß-catenin, cyclinD1 and c-Myc expression (0.5-fold; p < 0.001). In mouse HS models, HS skin thickness was thinner (1.60 ± 0.40 mm vs. 4.04 ± 0.36 mm; p < 0.001) after ZEB1 knockdown. CONCLUSIONS: Knockdown of ZEB1 inhibits HS formation both in vitro and in vivo. However, this is an in vitro/mouse model and more validation is needed. CLINICAL RELEVANCE STATEMENT: The discovery of ZEB1 as a mediator of HS formation might be a potential therapeutic target in HS treatment.

Mechanism of elastic energy storage of honey bee abdominal muscles under stress relaxation.

Energy storage of passive muscles plays an important part in frequent activities of honey bee abdomens due to the muscle distribution and open circulatory system. However, the elastic energy and mechanical properties of structure in passive muscles remain unclear. In this article, stress relaxation tests on passive muscles from the terga of the honey bee abdomens were performed under different concentrations of blebbistatin and motion parameters. In stress relaxation, the load drop with the rapid and slow stages depending on stretching velocity and stretching length reflects the features of myosin-titin series structure and cross-bridge-actin cyclic connections in muscles. Then a model with 2 parallel modules based on the 2 feature structures in muscles was thus developed. The model described the stress relaxation and stretching of passive muscles from honey bee abdomen well for a good fitting in stress relaxation and verification in loading process. In addition, the stiffness change of cross-bridge under different concentrations of blebbistatin is obtained from the model. We derived the elastic deformation of cross-bridge and the partial derivatives of energy expressions on motion parameters from this model, which accorded the experimental results. This model reveals the mechanism of passive muscles from honey bee abdomens suggesting that the temporary energy storage of cross-bridge in terga muscles under abdomen bending provides potential energy for springback during the periodic abdomen bending of honey bee or other arthropod insects. The finding also provides an experimental and theoretical basis for the novel microstructure and material design of bionic muscle.

Ferroptosis is a new therapeutic target for spinal cord injury.

Spinal cord injury is a serious traumatic disease. As Ferroptosis has been increasingly studied in recent years, it has been found to be closely related to the pathophysiological processes of spinal cord injury. Iron overload, reactive oxygen species accumulation, lipid peroxidation and glutamate accumulation associated with Ferroptosis are all present in spinal cord injury, and thus Ferroptosis is thought to be involved in the pathological processes secondary to spinal cord injury. This article highlights the relationship between Ferroptosis and spinal cord injury, lists substances that improve spinal cord injury by inhibiting Ferroptosis, and concludes with a discussion of the problems that may be encountered in the clinical translation of Ferroptosis inhibitors as a means of enabling their faster use in clinical treatment.

Research Progress of MicroRNAs in Spinal Cord Injury.

Spinal cord injury is a serious and devastating condition. Recently, research into microRNAs (miRNAs) has become increasingly exhaustive and it has been determined that they are closely related to the pathophysiological processes of spinal cord injury. They participate in the regulation of the inflammatory response of spinal cord injury, the death of neuronal cells, and the repair of neural functions, which are related to the recovery of spinal cord injury. This review focuses on the relationship between miRNA and spinal cord injury, lists miRNA-324-5p, miRNA-221 and miRNA-124, which are helpful for the repair of spinal cord injury, and finally summarizes the current research progress of miRNA-based therapies, so as to provide a foundational reference for clinical and scientific researchers.

Conjoint fascial sheath suspension with levator muscle advancement for severe blepharoptosis.

In patients with severe blepharoptosis, the function of the levator muscle is usually weak. Even if a large amount of levator is resected, under-correction and recurrence often occur postoperatively. Frontalis suspension is the first choice for severe ptosis; however, the external orbital lifting force of the frontalis causes non-physiological eyelid movement. Conjoint fascial sheath (CFS) is a fibrous tissue which can provide dynamic movement of upper eyelids and has been applied for the treatment of mild and moderate blepharoptosis in recent years. This study aims to assess the efficacy and safety of CFS suspension combined with levator muscle advancement for treating severe blepharoptosis. A retrospective study included 44 patients (60 eyelids) with severe ptosis who underwent the modified technique. Preoperatively, levator muscle function and margin reflex distance 1 (MRD1) were measured. Surgical outcomes, symmetry results and complications were evaluated postoperatively. At the 12-18 months follow-up, adequate or normal correction was achieved in 56 eyelids (93.3%), and 37 patients (84.1%) presented good or fair symmetry results. The most common complication was conjunctival prolapse, which was observed in six eyelids (10.0%), followed by lid fold deformity and under-correction. No exposure keratitis was recorded. In conclusion, the modified technique can physically elevate the eyelid with limited tissue injury and is effective for the correction of severe ptosis. Both satisfactory functional and esthetic results were achieved, and severe complications (such as exposure keratitis) were not observed.

Biomechanical properties of honeybee abdominal muscles during stretch activation.

The mechanical properties of the honeybee's abdominal muscles endow its abdomen with movement flexibility to perform various activities. However, the biomechanical properties of abdominal muscles during stretch activation remain unclear. To clarify this issue, we observed the microstructures of the abdominal muscles to obtain structural information. The similarity and symmetry of abdominal muscle distribution contribute to the ability to drive abdominal movement. Combined with the segmented structure characteristics, an experimental device to measure muscle stretch measurement of honeybees was developed to investigate the mechanical properties of the abdominal muscles. During measurement, the muscles were kept in a solution to maintain a physiological environment. The mechanical properties of abdominal muscles included phases: the ascending phase with proportional increase, stable phase with slight fluctuation, and decay phase with parabolic decline. These findings indicate that the nonlinear and rate-sensitive mechanical properties of the abdominal muscles enable them to rapidly adapt to environmental changes. The stretch force and stiffness coefficient reached 0.660 ± 0.139 mN and 14.364 ± 2.961 N/m, respectively. A simplified biomechanical model of the muscle fiber considering the hierarchical microstructure was introduced, in which the mechanical properties were consistent with the experimental data. Further analysis of the effects of the activation probability and the effective range of binding sites on the mechanical properties demonstrated the critical role in force generation, revealing the mechanism of underlying muscle stretch activation in the honeybee abdomen. The findings can provide a new reference for studying the biomechanical properties of the muscles of other arthropod insects.

Angiogenesis modulation-mediated inhibitory effects of tacrolimus on hypertrophic scar formation.

Hypertrophic scar (HS) is a fibroproliferative disorder that causes cosmetic as well as functional problems; however, to our knowledge, there is no satisfactory treatment for HS to date. Previous studies have indicated that angiogenesis plays a crucial role in HS formation; therefore, anti-angiogenetic therapies are considered effective in improving HS. Although tacrolimus (TAC) has been proven effective in preventing HS formation in vivo and in vitro, its underlying mechanism remains controversial and ambiguous. Because of its anti-angiogenic effects in other diseases, we aimed to determine whether TAC reduces HS by suppressing angiogenesis. Using a rabbit ear HS model that we developed, HS was treated once a week with normal saline, dimethyl sulfoxide, or TAC for 3 weeks. Histological evaluation indicated that TAC significantly reduced collagen deposition and microvessel density in scar tissues. Moreover, immunofluorescence staining for CD31 and vascular endothelial growth factor (VEGF)-A revealed that TAC significantly inhibited HS angiogenesis. In vitro analysis showed that TAC inhibited endothelial cell migration and tubulogenesis as well as the viability and proliferation of human umbilical vascular endothelial cells (HUVECs) and HS fibroblasts (HSFBs). Furthermore, TAC significantly downregulated the expression of the human angiogenetic factors VEGF-A, FGF-2, PDGF-ß, and TGF-ß1 in HUVECs and HSFBs. Additionally, TAC-mediated inhibition of angiogenesis decreased the gene expression of crucial fibrotic markers, including α- smooth muscle actin and collagens 1 and 3, in HSFBs. This is the first study to demonstrate the inhibitory effects of TAC on HS formation mediated by a mechanism involving the suppression of scar angiogenesis.

Sub-brow skin excision Combined with retro-orbicularis fat resection: A Technique for upper eyelid bulkiness and laxity correction.

BACKGROUND: Many people are characterized by a swollen appearance and loose skin of upper eyelids, especially Asians. Retro-orbicularis oculus fat (ROOF) lying in the lateral canthus area is a critical factor of the bulkiness formation. Although several approaches have been reported, most of them intend to remove orbicularis muscle and preaponeurotic fat through a double-eyelid incision, leaving ROOF untreated. Consequently, an unnatural eyelid fold is formed and the lateral supraorbital region remains bloated . METHODS: Sixty-seven patients underwent sub-brow skin excision combined with ROOF resection. The key point was to excise the loose skin and thick ROOF through an incision along with the lower 1/3 of the eyebrow. Surgical outcomes were evaluated 6 months postoperatively by the heights of the designed line from the palpebral margin to the pupil center (HPPC), medial cornea (HPMC), and lateral canthus (HPLC). The pinch test, photographs, and complications were also recorded. RESULTS: The preoperative average HPPC, HPMC, and HPLC were 9.68 ± 1.73, 7.68 ± 1.24, and 6.82 ± 1.12 mm, while the postoperative average measurements were 7.25 ± 0.51, 5.99 ± 0.54, and 5.54 ± 0.61 mm, respectively. The result of the pinch test was improved and postoperative scarring was inconspicuous. Two patients had transient numbness in the eyebrow region that subsided within seven days. Two patients had slight asymmetry of eyebrow position but did not need a second operation. CONCLUSIONS: Sub-brow skin excision combined with ROOF resection is an effective technique for improving upper eyelid bulkiness and skin excess with low revision rates.

A Child Infected with COVID-19 in China-A Case Report.

A 16-month-old boy was admitted with cough for 2 days and fever for 1 day. Chest computed tomography (CT) scan of the child revealed large areas of ground-glass opacities in both lungs. Nucleic acid amplification tests (NAATs) were performed repeatedly to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but the results were all negative. On day 13 of hospitalization, no clinical symptoms except diarrhea were present in the patient, and re-examination by chest CT revealed lesion shrinkage, but the NAAT on throat swabs was positive. On day 22 of hospitalization, the NAAT on throat swabs was negative and the fecal samples were positive. Positive fecal samples nucleic acid lasted for 62 days. Suggesting that pediatric patients may be important sources of infection during the recovery phase of clinical symptoms and whether SARS-CoV-2 has fecal-oral transmission needs further study.

A Modified Approach to Transconjunctival Levator Advancement Offering Intraoperative Options.

BACKGROUND: The transconjunctival technique is an effective approach to mild to moderate blepharoptosis repair that does not involve skin incision. However, accurate surgical manipulation of this method is greatly restricted by poor intraoperative evaluation. OBJECTIVES: The aim of this study was to introduce a modified transconjunctival approach with flexible intraoperative adjustments in order to achieve more accurate ptosis correction. METHODS: Taking a transconjunctival approach, the levator aponeurosis and Müller's muscle were folded with a square-like mattress suture for flexible adjustment and accurate correction. RESULTS: In 18 mild ptosis eyelids, 94.5% (17 eyelids) achieved adequate or normal correction. In 9 eyelids with moderate ptosis, 88.9% (8 eyelids) achieved adequate or normal correction. Of 24 ptosis patients, 23 (95.8%) achieved a good or fair symmetry result. CONCLUSIONS: This study presents a modified transconjunctival technique for repair of mild to moderate ptosis, which is characterized by flexible intraoperative adjustments that produce satisfying functional and aesthetic outcomes.