Objective To explore the relationship between plantar fascia stiffness and windlass mechanism and their impact on the arch,and provide a biomechanical mechanism explanation for plantar fascia and arch-related diseases.Methods A foot-plate model with 30° flexion angle at the metatarsophalangeal joint was constructed.The musculoskeletal model combined with the three-dimensional finite element analysis method was used,and the dynamic data of the foot during walking at the speed of 5 km/h was obtained using dual fluoroscopic imaging system(DFIS).The finite element model was verified,and the influence of plantar fascia stiffness on the capstan mechanism and arch-related mechanical parameters was explored.Results The finite element simulation analysis results were highly consistent with the foot data obtained by DFIS,confirming the validity of the model.With the increase of plantar fascia stiffness,the windlass effect and the stiffness of the longitudinal arch of the foot both showed an increasing trend,but the flexion angle of the metatarsophalangeal joint decreased,the distal stress of the plantar fascia gradually decreased,and the proximal stress increased;when the plantar fascia stiffness was 25％-150％,the width of the transverse arch of the foot increased with the increase of plantar fascia stiffness,while the height of the transverse arch decreased with the increase of plantar fascia stiffness;when the plantar fascia stiffness was 150％-200％,the width of the transverse arch of the foot decreased,the height increased,and the stiffness also increased.Conclusions An increase in plantar fascia stiffness can enhance the windlass mechanism to some extent,but it also leads to a reduction in metatarsophalangeal joint flexion.The stiffness of the plantar fascia affects the metatarsophalangeal joint flexion,thereby impacting the windlass mechanism and the distal tensile force of the plantar fascia.Together with the ground reaction force at the distal end of the metatarsals,these factors collectively influence the stiffness of the transverse arch of the foot.

Objective To explore the relationship between plantar fascia stiffness and windlass mechanism and their impact on the arch,and provide a biomechanical mechanism explanation for plantar fascia and arch-related diseases.Methods A foot-plate model with 30° flexion angle at the metatarsophalangeal joint was constructed.The musculoskeletal model combined with the three-dimensional finite element analysis method was used,and the dynamic data of the foot during walking at the speed of 5 km/h was obtained using dual fluoroscopic imaging system(DFIS).The finite element model was verified,and the influence of plantar fascia stiffness on the capstan mechanism and arch-related mechanical parameters was explored.Results The finite element simulation analysis results were highly consistent with the foot data obtained by DFIS,confirming the validity of the model.With the increase of plantar fascia stiffness,the windlass effect and the stiffness of the longitudinal arch of the foot both showed an increasing trend,but the flexion angle of the metatarsophalangeal joint decreased,the distal stress of the plantar fascia gradually decreased,and the proximal stress increased;when the plantar fascia stiffness was 25％-150％,the width of the transverse arch of the foot increased with the increase of plantar fascia stiffness,while the height of the transverse arch decreased with the increase of plantar fascia stiffness;when the plantar fascia stiffness was 150％-200％,the width of the transverse arch of the foot decreased,the height increased,and the stiffness also increased.Conclusions An increase in plantar fascia stiffness can enhance the windlass mechanism to some extent,but it also leads to a reduction in metatarsophalangeal joint flexion.The stiffness of the plantar fascia affects the metatarsophalangeal joint flexion,thereby impacting the windlass mechanism and the distal tensile force of the plantar fascia.Together with the ground reaction force at the distal end of the metatarsals,these factors collectively influence the stiffness of the transverse arch of the foot.

Cholesteatoma of the middle ear is a common disease in otolaryngology that is receiving increasing attention. It is estimated that over five million people around the world have suffered from middle ear cholesteatoma. The annual incidence of middle ear cholesteatoma has been reported to be 9.2 per 100,000 in adults and 3 per 100,000 in children. Without timely discovery and intervention, cholesteatomas can become perilously large and damage intratemporal structures, causing various intracranial and extracranial complications. No practical nonsurgical treatments are currently available. Although multiple hypotheses exist, research directions have consistently focused on cell proliferation, apoptosis, and bone destruction. Non-coding RNAs (ncRNAs), especially microRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs), have recently received increasing attention because of their key roles in gene expression, cell cycle regulation, and the development of many diseases. Although ncRNAs are not involved in protein translation, they are abundant in the genome, with only approximately 2% of genes encoding proteins and the remaining approximately 98% encoding ncRNAs. The purpose of this review is to summarize the current state of knowledge regarding the specific role of ncRNAs in middle ear cholesteatoma.

ObjectiveTo systematically review the intervention effect of Chinese medicine on the structure and function of testicular Sertoli cells in animal models of impaired spermatogenesis. MethodThe databases， such as China National Knowledge Infrastructure （CNKI），VIP，Wanfang Data，EMbase，and Pubmed，were searched for experimental studies on the effect of Chinese medicine on the structure and function of testicular Sertoli cells in animal models with impaired spermatogenesis. The included studies were evaluated for risks of bias，and the outcome indicators were analyzed with RevMan and Stata software. ResultThirty studies were included，involving 37 randomized controlled trials （RCTs）. As indicated by the Meta-analysis results， compared with the model group，Chinese medicine increased sperm density（SMD=2.42，95% confidence interval（CI）［1.47，3.37］，P<0.000 01）， promoted sperm motility（SMD=2.35，95%CI ［1.70， 2.99］，P<0.000 01）， up-regulated the protein and mRNA levels of Vimentin （related to Sertoli cell cytoskeleton）， elevated the levels of Occludin and Claudin-11 （related to tight junction of blood-testis barrier）， boosted the levels of β-catenin and N-cadherin （related to adherens junction of blood-testis barrier）， raised the level of connexin 43 （Cx43， related to gap junction of blood-testis barrier）， improved the function of Sertoli cells， increased the serum content of Inhibin B （INHB）， and up-regulated the levels of testicular follicle-stimulating hormone receptor （FSHR）， INHB mRNA， androgen-binding protein （ABP） mRNA， transferrin（TF），stem cell factor（SCF），SCF mRNA，glial cell line-derived neurotrophic factor （GDNF），GDNF mRNA，bone morphogenetic protein 4（BMP4），and BMP4 mRNA （P<0.05）. ConclusionChinese medicine can effectively increase sperm density and motility of animal models of impaired spermatogenesis，and improve the structure and function of testicular Sertoli cells. However，affected by the quality of the included studies，the above conclusion needs to be further verified by relevant high-quality studies.

Objective:To analyze the clinical and imaging characteristics of acute necrotic encephalopathy (ANE) in a child with human herpesvirus-6 (HHV-6) infection.Methods:Retrospective analysis was performed on the clinical data and imaging features of a case of HHV-6 related ANE from Children′s Hospital Affiliated to Zhengzhou University in March 2019.Results:The one year and seven month-old child had acute encephalopathy, recurrent convulsions, consciousness disorders, elevated serum transaminase. The number of cerebrospinal fluid (CSF) cells was normal and the protein increased. High throughput gene testing of CSF showed HHV-6. Cranial magnetic resonance imaging showed multiple symmetry damage in the bilateral thalamus, brainstem, and cerebellum. The symptoms improved after the treatment of glucocorticoids, intravenous immunoglobulin, and plasmapheresis.Conclusions:ANE is a rare severe encephalopathy, the characteristic imaging change of which is symmetry multifocal cerebral damage, especially in the bilateral thalamus. ANE should be considered for patients with frequent convulsions and disturbance of consciousness after virus infection.

Objective:To investigate the clinical phenotypes, therapy and genetic features of aldehyde dehydrogenase 7 family member A1 (ALDH7A1) gene mutations in five cases of pyridoxine dependent epilepsy (PDE) with diagnosis confirmed by next generation sequencing.Methods:Retrospective analysis was carried out on clinical data of five cases of PDE children with early epilepsy onset who were treated in the Department of Neurology of Children′s Hospital Affiliated to Zhengzhou University from February 2018 to November 2019. Next generation sequencing approach was used for genetic sequencing of proband ALDH7A1 gene and the first generation Sanger was used for validation of family members. And the characteristics of gene mutations were analyzed.Results:Among the five children diagnosed with PDE, the male to female ratio was 4 ∶ 1 and ages at clinic visit ranged from two months to 10 months old. In clinical phenotypes, all five cases experienced onset in neonatal period, with repeated seizures, manifested as myoclonus, spasms or focal paroxysm. The administration of antiepileptic drugs performed poorly in seizure control while long term oral intake of large dose pyridoxine showed better efficacy. All the five cases of children came from compound heterozygous mutations of father and mother, i.e. slicing homozygous mutation c.247-2(IVS2)A>T, missense mutation c.584A>G (p.N195S) and nonsense mutation c.1003C>T(p.R335 *), missense mutation c.1553G>C(p.R518T) and c.1547A>G(p.Y516C), missense mutation c.1547A>G(p.Y516C) and frameshift mutation c.1566_1568delTAC, missense mutation c.1061A>G(p.Y354C) and nonsense mutation c.841C>T(p.Q281X, 259), among which c.247-2(IVS2)A>T was novel splicing site mutation not reported before. Conclusions:PDE is induced by ALDH7A gene mutation. Early clinical manifestations are mostly onset of refractory epilepsy in neonatal period. Antiepileptic drugs perform poorly in terms of efficacy while pyridoxine can control seizure effectively. Gene analysis should be conducted on such patients for confirmed diagnosis.

Objective:To investigate the clinical characteristics and gene mutation of seven cases of CDKL5 gene related early-onset epileptic encephalopathy diagnosed by next-generation sequencing.Methods:The clinical data of children with early-onset epileptic encephalopathy from February 2018 to December 2019 in the Department of Neurology, Children′s Hospital Affiliated to Zhengzhou University were retrospectively analyzed. The whole exome sequencing method was used to analyze the entire exome of the proband, and seven cases of CDKL5 gene mutation positive were screened out, and Sanger sequencing verification on family members was performed to identify the source and the characteristics of gene mutations were analyzed.Results:Among the seven children diagnosed with CDKL5 gene related early-onset epileptic encephalopathy, the ratio of male to female was 2∶5, and the age of onset was 15 days to five months of birth. The clinical phenotypes all included different degrees of developmental delay and repeated seizures, which were manifested as general seizures, myoclonic seizures, convulsive seizures or focal seizures; the outcome of use of antiepileptic drugs to control seizures was poor, and some applications of ketogenic diet had better effects. CDKL5 gene mutation sites were all denovo mutations, including NM_003159: c.772_776del (p.K258Efs *10) frameshift mutation, NM_003159.2 (exon: 9-15) heterozygous deletion, CDKL5 hemizygous deletion, NM_003159: c.268 (exon5) G>T (p.E90 *, 941) and NM_003159: c.2578C>T (p.Q860 *, 171) nonsense mutation, NM_003159: c.211A>G (p.Asn71Asp) and NM_001323289: c.545T>C (p.L182P) missense mutation. Among them, c.772_776del (p.K258Efs *10), c.268 (exon5)G>T and c.2578C>T (p.Q860 *, 171) have not been reported. Conclusions:CDKL5 gene related early-onset epileptic encephalopathy is an early onset epilepsy, which is more common in women, and has different forms of seizures. The early electroencephalogram is characterized as severe abnormal brain discharge, and the disease progresses in various forms. There are no specific changes in head magnetic resonance imaging. Different gene mutation sites may lead to different phenotypes and prognostic differences. Many anti-epileptic treatments are ineffective, and ketogenic diets are effective for some patients.

Under the background of technological assistance to prepare for the Beijing Winter Olympics in China, the biomechanical research highlights and the latest achievements related to competitive performance of alpine skiers in recent years were systematically analyzed in this paper, so as to determine biomechanical factors affecting competitive performance of alpine skiers, including aerodynamic drag, frictional forces, ground reaction force (GRF), energy dissipation, turn radius, trajectory of the skis and/or center of mass (COM). In addition, biomechanical differences in turn techniques, multiple turns connections and abilities of individuals were also considered as important factors affecting the alpine skiing performance. In the case of slalom and giant slalom events, the earlier initiation of turns, longer path length and trajectory, earlier and smoother application of GRF, and carbene technique carving to reduce the ski-snow friction and thereby dissipate energy should be used to improve sports performance. During speed skiing, minimizing the exposed frontal area and positioning the arms close to the body can reduce the energy loss caused by aerodynamic drag, thereby improving sports performance. Top-level alpine skiers will always perform well on different courses, terrains and snow conditions during the race. Excellent alpine ski performance from a biomechanical perspective includes the efficient use of potential energy, minimizing ski-snow friction and aerodynamic drag, choosing optimal trajectory and maintaining high-speed skiing. Individual tactics and techniques should be valued in training and competition. For better results, the same performance on multiple sections and on different terrains is more important than excellence in individual sections and specific conditions.

OpenSim musculoskeletal modelling has developed rapidly and been widely utilized due to its open-source. Apart from calculation of the basic kinematic and kinetic data, subject-specific OpenSim model could reveal information of neuromuscular control, muscle forces and geometry, and contact forces. Image-based model-ling of the neuromuscular control in pathological gait and ergonomic evaluation of the prostheses confirmed the reliability and feasibility, but limitations in time-consumption and foot-ankle modelling also existed. The subject-specific modelling of pathological gait could improve the accuracy and diversity of clinical biomechanics and medical engineering research. It could also reveal the pathological features, and provide scientific evidence to design specific and accurate protocols of motor function diagnosis and rehabilitation, health monitoring and evaluation, and ergonomic customization and assessment of devices, as well as future directions and implications in the research field.

Objective:To summarize the clinical features and genetic etiology of tuberous sclerosis (TSC).Methods:A retrospective analysis was carried out to identify the clinical features and auxiliary examination reults of TSC patients in 2 pedigrees admitted to our hospital from January 2018 to April 2018. Whole exome sequencing was performed in peripheral blood samples from these patients and the mutations in their parents were validated by Sanger sequencing.Results:The two probands were a one-year and 7-month old girl and a 2-year and 4-month old boy. They were all normal at birth and had epileptic seizures at preschool age. The elder sister, younger sister and mother of the probands showed abnormal skin and no seizures, and the father had normal phenotype. Physical examination showed normal mental and motor development, facial angiofibroma and depigmentation spots on the skin, knots and shark-like spots on part of the skin, and multiple intracranial calcification shadows on head CT; MR imaging revealed multiple abnormal signals under the parenchymal cortex and bilateral lateral ventricles. The proband (1) and her sister carried heterozygous missense mutation c.5024 c >T(p.pro1675leu) in TSC2 gene; ultrasound of heart, liver and kidney showed presence of hamartoma and cystic scotoma in renal parenchyma. The proband (2) and his younger sister carried heterozygosous splicing variation c. 737+1(IVS8)G>A in TSC1 gene, inherited from his mother; the head CT of younger sister was normal, and there was no hamartoma in the younger sister and the mother's internal organs. Conclusions:TSC is characterized by epileptic seizures and abnormal skin changes in preschool age. It may involve multiple hamartomas of skull, heart, liver, kidney, or other internal organs. The mutation frequency of TSC2 gene is higher than that of TSC1 gene, and the clinical phenotype is severe.