[ ABSTRACT] Rebound depolarization is a special phenomenon of the neurons which generates action potential fol-lowed by a hyperpolarization stimulation.It can be recorded in many kinds of neurons and is the intrinsic membrane charac-teristic of them.Rebound depolarization plays an important role in regulating the firing pattern, rhythmic activity and sy-naptic plasticity of neurons.This review focuses on the basic characteristics, the function and mechanism of the rebound depolarization in physiological and pathological conditions, which provides reference for the clinical treatment of rebound depolarization-related diseases.

Objective:To investigate the effect of periacetabular osteotomy (PAO) assisted by preoperative 3D printing planning on the treatment of early developmental dislocation of the hip (DDH).Methods:A retrospective study was conducted of the 39 patients (44 hips) with CROWE type Ⅰ DDH who had been treated at Department of Orthopaedics, Guizhou Provincial People＇s Hospital from May 2015 to April 2019. In the observation group of 19 patients (22 hips) who were treated by PAO assisted by preoperative 3D printing planning, there were 4 males (4 hips) and 15 females (18 hips) with a mean age of 23(19, 39) years; in the control group of 20 patients (22 hips) who were treated by mere PAO, there were 2 males (2 hips) and 18 females (20 hips) with a mean age of 23(20, 29) years. The 2 groups were compared in terms of operation time, intraoperative bleeding, hospital stay, fluoroscopic frequency, Wiberg lateral center-edge angle (LCE), acetabular index (AC), acetabulum coverage rate, Harris hip scores (HHS) and complications at the final follow-up.Results:There were no significant differences between the 2 groups in their preoperative general data, showing compatibility of the 2 groups ( P>0.05). Both groups were successfully followed up for 6 to 12 months (mean, 9.6 months). The operation time [100 (90, 120) min], intraoperative bleeding [160 (150, 180) mL], hospital stay [6 (5, 7) d], and fluoroscopic frequency [24 (22, 25) times] in the observation group were all significantly better than those in the control group [140 (100, 157) min, 200 (180, 250) mL,9(7, 11) d and 28 (24, 32) times] in the control group ( P<0.05). However, there were no significant differences between the 2 groups in LCE, AC or acetabulum coverage rate immediately after operation, or in HHS or complications at the final follow-up( P>0.05). Conclusions:Although PAO has a definite therapeutic effect on early DDH, PAO assisted by preoperative 3D printing planning can effectively reduce operation time, intraoperative bleeding, hospital stay and intraoperative fluoroscopy. Thus, combination of the two can result in a better therapeutic effect than PAO alone.

Objective:To study the value of ultrasound-guided endoscopic retrograde appendicitis therapy in children with uncomplicated appendicitis.Methods:This study was a single center, retrospective study, including all electronic cases of appendicitis diagnosed clinically in Department of Pediatrics, the Second Affiliated Hospital of Air Force Military Medical University from October 2018 to October 2020 and received ultrasound-guided endoscopic retrograde appendicitis therapy.The clinical features, treatment and prognosis of the children were retrospectively analyzed.Results:A total of 152 electronic cases were included, there were 77 males and 75 females, aged(6.84±3.09) years.All the 152 children were treated with ultrasound-guided endoscopic retrograde appendicitis therapy.Intubation success rate and clinical success rate was 98.03%(149/152 cases)and 97.99%(146/149 cases), respectively.The median time of endoscopic therapy was 42.50 (31.00, 56.00) minutes.Mean postoperative hospital stay was (2.81 ±1.41) days, and the mean total hospital stay was (4.19 ±1.71) days.A total of 139 patients were followed up with a median follow-up time of 5 (1, 26) months.During the follow-up, the recurrence rate was 7.19%(10/139 cases), and the median time of recurrence was 2 (1, 3) months.Conclusions:Ultrasound-guided endoscopic retrograde appendicitis therapy had high effective rate and low recurrence rate in children with uncomplicated appendicitis, preserved the physiological function of appendix and avoided radiation damage.It can be used as a safe and effective treatment for acute and chronic uncomplicated appendicitis in children.

OBJECTIVETo investigate the effect of minocycline on hyperpolarization-activated current (Ih) in the substantia gelatinosa (SG) neurons in rat spinal dorsal horn.

METHODSIn vitro spinal cord transverse slices were prepared from 3-5-week-old male Sprague-Dawley rats. Using whole-cell patch clamp technique, Ih currents were recorded before and after bath application of minocycline (1-300 µmol/L) to the SG neurons.

RESULTSIh currents were observed in nearly 50% of the recorded neurons, and were blocked by Ih blocker CsCl and ZD7288. Minocycline rapidly and reversibly reduced the amplitude of Ih and decreased the current density in a concentration-dependent manner with an IC50 of 34 µmol/L.

CONCLUSIONMinocycline suppresses the excitability of SG neurons through inhibiting the amplitude and current density of Ih and thereby contributes to pain modulation.

Animals ; Male ; Minocycline ; pharmacology ; Neurons ; drug effects ; Patch-Clamp Techniques ; Rats ; Rats, Sprague-Dawley ; Substantia Gelatinosa ; cytology

The patient is a young woman,manifested as orthostatic hypotension and gastrointestinal motility disorders in acute onset.The physical examination and laboratory test suggested disorders of wide range of autonomic neuropathy.The levels of serum antinuclear antibody and SSA antibody were elevated.The biopsy of lip gland suggested Sjogren's syndrome.Nerve biopsy showed loss of a large number of unmyelinated nerve fibers.After the treatment of intravenous gamma globulin and glucocorticoid and symptomatic treatment,the symptoms of orthostatic hypotension were significantly relieved,but the gastrointestinal motility was not significantly improved.

Objective To investigate the efficacy of CT scanning for 3D reconstruction and 3D printing in the internal fixation for in situ femoral condyle fractures.Methods A retrospective study was conducted of the 111 patients with in situ femoral condyle fracture who had been treated by internal fixation at Department of Traumatic Orthopaedics,The First People's Hospital of Hefei from June 2013 to January 2018.They were 59 males and 52 females,aged from 20 to 59 years(average,47 years).In 74 of them (observation group),the internal fixation was assisted by 3D printing using 3D images.There were 38 males and 36 females with an age of 44.5 ±4.7 years;there were 20 cases of type C1,40 cases of type C2 and 14 cases of type C3 according to the AO classification.In the other 37 patients (control group),the operation was assisted only by 3 D scanning.There were 21 males and 16 females with an age of 43.1 ±4.6 year;there were 8 cases of type C1,19 cases of type C2 and 10 cases of type C3 according to the AO classification.The 2 groups were compared in terms of operation time,clinical fracture healing time,intraoperative blood loss,hospital stay,number of fluoroscopy,knee joint score of Hospital for Special Surgery (HSS),fixation modes and postoperative complications.Results There were no significant differences in the preoperative general data between the 2 groups,showing comparability (P ＞ 0.05).All the patients were followed up for 8 to 12 months (average,10.6 months).The observation group had significantly shorter operation time (62.3 ± 4.7 minutes),fracture healing time (21.2 ± 3.4 weeks) and hospital stay (14.9 ± 3.3 days) than the control group (89.5 ± 6.0 minutes,25.1 ± 3.5 weeks,23.5 ± 3.5 days) (P ＜ 0.05).In the observation group,the intraoperative blood loss (84.1 ± 11.1 mL),fluoroscopy number (2.1 ±0.3 times) and HSS score (94.1 ± 4.2 points) were significantly less than those in the control group (129.6 ± 14.7 mL,4.7 ± 0.4 times and 86.5 ± 4.6 points) (P ＜ 0.05).There were no significant differences between the 2 groups in the use of L type iliac plate,dynamic iliac screws,retrograde interlocking intramedullary nail or minimally invasive internal fixation system (P ＞ 0.05).There were no significant differences in abnormal healing,joint adhesion,fixation fracture or incision infection between the 2 groups either (P ＞ 0.05).Conclusions CT scanning for 3D reconstruction can be used for multi-angle observation of the bone fragments in patients with femoral condyle fracture and 3D printing based on 3D reconstruction for manufacture of physical model of individualized fracture to assist the internal fixation.Combination of the two can help choose an appropriate fixation mode to facilitate fracture reduction.

Objective:To summarize the clinical and gene mutation characteristics of a child with Cowden syndrome and review the literature.Methods:The clinical data of a child with Cowden syndrome treated in the First Affiliated Hospital of Xinxiang Medical University in June 2020 were analyzed retrospectively.Taking " Cowden syndrome" , " PTEN gene" , " hamartoma polyps" , "child" , " Cowden syndrome and child" and " PTEN and child" as key words, literature was retrieved from Chinese databases (China National Knowledge Internet database and Wanfang database) and the PubMed database from the establishment of the database to March 2021. Results:A 13-year-old male had intermittent abdominal pain and abdominal distension for 5 months.Electron microscopic gastroenteroscopy showed multiple polyps, and focal lymphocyte aggregation and infiltration were found in tissue biopsy.Whole exon sequencing revealed a hemizygous mutation of c. 475 (exon5) A>T in PTEN gene, which led to the transformation of the 159 th amino acid from arginine to tryptophan.The prediction results of the tertiary structure of the protein indicated that the variation might affect the spatial structure of the protein and damage the protein function.According to the clinical characteristics, Cowden syndrome was diagnosed.The pedigree confirmed that the variation was inherited from the mother, who had a similar phenotype.No qualified Chinese report was retrieved.Among 41 English studies on PTEN gene mutation in children, there were only two reports related to pediatric Cowden syndrome.The hemizygous mutation of PTEN gene was not reported. Conclusions:The missense mutation of c. 475 (exon5) A>T in PTEN gene in this study is a novel cause of Cowden syndrome, and the case is the first case report in China.

To investigate the efficacy and safety of modified endoscopic retrograde appendicitis therapy (ERAT) in children with acute uncomplicated appendicitis complicated with intussusception. Data of 6 patients with acute uncomplicated appendicitis complicated with intussusception who received modified ERAT were collected from October 2018 to February 2020 in Pediatrics Department of Tangdu Hospital. The reduction rate of intussusception, the success rate of ERAT appendiceal intubation and endoscopic treatment, the remission time of clinical symptoms, the time of white blood cells return to normal, the length of hospital stay, complications and recurrence were summarized. All the 6 patients were confirmed to be acute uncomplicated appendicitis combined with ileocecal intussusceptions under colonoscopy. Endoscopic intussusception reduction and ERAT were performed successfully. The mean time of disappearance of abdominal tenderness was 1.3 days after the therapy, and the time of white blood cells return to normal was 1 day after surgery. The endoscopic treatment were all successful and the length of hospital stay was 3-6 days. No complications or recurrence of intussusception and appendicitis occurred during the follow-up period of 6-12 months. Modified ERAT can effectively, safely and minimally invitingly treat acute uncomplicated appendicitis with intussusception in children on the basis of definite diagnosis.

PURPOSE: Previous studies have confirmed that microRNAs play important roles in the pathogenesis of acute aortic dissection (AAD). Here, we aimed to explore the role of miR-145 and its regulatory mechanism in the pathogenesis of AAD. MATERIALS AND METHODS: AAD tissue samples were harvested from patients with aortic dissection and normal donors. Rat aortic vascular smooth muscle cells (VSMCs) were transfected with miR-145 mimic/inhibitor or negative control mimic/inhibitor. Gene and protein expression was measured in human aortic dissection tissue specimens and VSMCs by qRT-PCR and Western blot. Luciferase reporter assay was applied to verify whether connective tissue growth factor (CTGF) was a direct target of miR-145 in VSMCs. Methyl thiazolyl tetrazolium assay was used to detect VSMC viability. RESULTS: miR-145 expression was downregulated in aortic dissection tissues and was associated with the survival of patients with AAD. Overexpression of miR-145 promoted VSMC proliferation and inhibited cell apoptosis. Moreover, CTGF, which was increased in aortic dissection tissues, was decreased by miR-145 mimic and increased by miR-145 inhibitor. Furthermore, CTGF was confirmed as a target of miR-145 and could reverse the promotion effect of miR-145 on the progression of AAD. CONCLUSION: miR-145 suppressed the progression of AAD by targeting CTGF, suggesting that a miR-145/CTGF axis may provide a potential therapeutic target for AAD.
Animals ; Apoptosis ; Blotting, Western ; Connective Tissue Growth Factor ; Humans ; Luciferases ; MicroRNAs ; Muscle, Smooth, Vascular ; Rats ; Tissue Donors

Objective:To summarize the clinical, pathological and muscle magnetic resonance imaging (MRI) features of human immunodeficiency virus (HIV)-associated nemaline myopathy (NM; HIV-NM).Methods:The present patient was a 23-year-old man with HIV infection who developed progressive proximal weakness and atrophy for more than 10 months. He was admitted to the Department of Neurology of Beijing Ditan Hospital in early June 2021. Electromyography showed myogenic findings. The serum creatine kinase was 202.4 U/L. CD 4+ count was 585×10 6/L. Serum monoclonal immunoglobulin (M protein) was negative. The patient underwent MRI examination of bilateral thigh muscles, biopsy of left biceps brachii and gene detection. The clinical, pathological and muscle MRI changes of HIV-NM were summarized based on the literature review. Results:MRI examination of bilateral thigh muscles showed edema changes. Muscle biopsy showed nemaline structures in some muscle fibers, accompanied by fiber atrophy and regeneration. No gene mutation related to clinical phenotype was found by second-generation sequencing. After intravenous immunoglobulin combined with prednisone, the patient′s weakness symptoms were significantly improved. A total of 17 cases of HIV-NM (including the present case) were identified in the literature, who were aged (33.7±9.1) years. Fifteen were males and two were females. All patients developed proximal limb weakness. Creatine kinase was normal or slightly elevated. Serum monoclonal protein was positive in 3 cases (3/7). Immunosuppressive therapy was effective.Conclusions:The main clinical characteristics of HIV-NM are progressive proximal limb weakness and muscle atrophy. The muscle pathology shows a large number of nemaline structures in atrophic muscle fibers. Muscle edema can be seen on muscle MRI. This is the first report of HIV-NM in China, which may be a special subtype of immune myopathy.