Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle weakness.It is one of the most common genetic causes of mortality among infants aged less than 2 years.Biomar...Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle weakness.It is one of the most common genetic causes of mortality among infants aged less than 2 years.Biomarker research is currently receiving more attention,and new candidate biomarkers are constantly being discovered.This review initially discusses the evaluation methods commonly used in clinical practice while briefly outlining their respective pros and cons.We also describe recent advancements in research and the clinical significance of molecular biomarkers for spinal muscular atrophy,which are classified as either specific or non-specific biomarkers.This review provides new insights into the pathogenesis of spinal muscular atrophy,the mechanism of biomarkers in response to drug-modified therapies,the selection of biomarker candidates,and would promote the development of future research.Furthermore,the successful utilization of biomarkers may facilitate the implementation of gene-targeting treatments for patients with spinal muscular atrophy.展开更多
Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen r...Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy patients.These aggregates alter protein-protein interactions and compromise transcriptional activity.In this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic factor.Overexpressio n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor aggregation.Conversely.knocking down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor aggregation.Our findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy.展开更多
Duchenne muscular dystrophy (DMD) is a hereditary, progressive muscular disorder inherited in an X-linked recessive pattern (Xp21). It typically manifests in childhood and follows a severe, rapid progression. Only mal...Duchenne muscular dystrophy (DMD) is a hereditary, progressive muscular disorder inherited in an X-linked recessive pattern (Xp21). It typically manifests in childhood and follows a severe, rapid progression. Only males are affected, while females are usually carriers. Given the genetic nature of DMD, genetic counseling is an essential service for individuals affected by or at risk of carrying the disease. This service provides not only crucial medical information but also psychosocial support and ongoing management for both patients and their families. Since the discovery of the dystrophin gene in 1987, advancements in molecular genetics have made it possible to precisely identify the genes responsible for many neuromuscular diseases. These developments have revolutionized diagnosis, prognosis, and most importantly, genetic counseling, offering significant benefits for both patients and their families. To highlight the significance of these advancements, this case report focuses on a 10-year-old boy (Y) diagnosed with DMD. It emphasizes the familial nature of the disease, with Y’s two brothers, three cousins, and two maternal uncles also affected, underscoring the inherited pattern of DMD. This reinforces the critical need for early intervention, particularly in regions with high consanguinity, such as North Africa and the Middle East, where genetic counseling and prenatal diagnosis are even more essential. Additionally, the report explores the clinical presentation, diagnostic findings, and promising emerging treatments, including RNA-based therapies, which may play a key role in the future management of DMD. In light of the above, this study underscores the importance of prenatal diagnosis and genetic counseling, particularly in regions like Morocco, where consanguinity rates are notably high. By focusing on preconception care and early genetic intervention, families can be better informed, leading to more effective disease management and support.展开更多
Objectives:As the Duchenne Muscular Dystrophy(DMD)is a progressive neuromuscular disorder frequently associated with cardiac dysfunction,this study aimed to evaluate the influence of beta-blocker therapy on cardiac au...Objectives:As the Duchenne Muscular Dystrophy(DMD)is a progressive neuromuscular disorder frequently associated with cardiac dysfunction,this study aimed to evaluate the influence of beta-blocker therapy on cardiac autonomic modulation in adolescents withDMDby analyzing heart rate variability(HRV)indices in patients with and without betablockers.Methods:A cross-sectional study was conducted with 90 participants divided into three groups:(1)participants with DMD receiving beta-blocker therapy(DMDB,n=30),(2)participants with DMD without beta-blocker therapy(GMDM,n=30),and(3)age-and sex-matched typically developing participants(GDT,n=30).HRV was assessed using validated beat-to-beat heart rate monitoring(RS800CX,Polar)under controlled conditions.Linear and non-linear HRV indices(including Detrended Fluctuation Analysis and Symbolic Dynamics)were analysed using Kubios HRV software.Results:DMD patients exhibited autonomic impairment,characterized by decreased HRV,increased sympathetic dominance,and reduced parasympathetic modulation.Betablocker therapy was associated with significantly higher Mean Beat-to-beat interval(RR)and lower Mean Heart Rate(HR)compared to the non-beta-blocker DMD group,with values approaching those observed in typically developing participants.Non-linear indices suggested thatDMDpatients receiving beta-blockers demonstrated increased HRV complexity and fractal properties compared to those not receiving beta-blockers,although differences remained between the DMD and control groups.Conclusions:Autonomic dysfunction in DMD is characterized by reduced HRV and altered sympathovagal balance.In our results,beta-blocker therapy was associated with improved HRV and enhanced autonomic control.These findings highlight the potential cardioprotective role of betablockers in DMD management and emphasize the need for further research into optimizing autonomic function in DMD.展开更多
BACKGROUND Duchenne muscular dystrophy(DMD)is a neuromuscular disorder caused by mutations in the dystrophin gene.DMD is reported to coexist with other comorbidities,although the occurrence of the triad,autism spectru...BACKGROUND Duchenne muscular dystrophy(DMD)is a neuromuscular disorder caused by mutations in the dystrophin gene.DMD is reported to coexist with other comorbidities,although the occurrence of the triad,autism spectrum disorder(ASD),and epilepsy is very rare.Indeed,only one case of the triad has currently been reported.Here,we present a detailed case report of a ten-year-old boy with DMD,ASD,and epilepsy.We also investigated the dysregulation of miRNAs in this unusual triad(represented as DMD++)compared with a healthy individual and a DMD patient(represented as DMD+)without autism.AIM To understand the differential expression of miRNAs in rare comorbid DMD cases.METHODS The Sequin Form Board test,Gesell's drawing test,multiplex ligation probe amplification,and Vineland Social Maturity Scale were applied to confirm the DMD and ASD.Total RNA was isolated from samples using TRIzol.cDNA was synthesized using the Mir-X^(TM)miRNA First-Strand Synthesis kit.qRT-PCR was performed using SYBR Advantage qPCR Premix.The results were statistically analyzed using one-way analysis of variance with Tukey's ttest.RESULTS miR-146a-5p and miR-132-5p showed significant downregulation in both patient samples.miR-199a-5p and miR-146a-3p showed no change in expression between the diseased and controls.miR-132-3p showed downregulation only in the DMD+sample(0.21±0.04).The decrease in miR-132-3p can result in failed silencing of the phosphatase and tensin homolog-mediated apoptotic pathway,leading to severe skeletal muscle atrophy.Here,the downregulation of miR-132-3p in DMD+is consistent with severe muscle loss and higher disease progression than that in DMD++.DMD++has slower disease progression,and the expression of miRNA involved in inflammatory and apoptotic responses is more similar to that of the control.CONCLUSION Our study shows marked difference in miRNA expression in this rare case of DMD with autism and epilepsy.These miRNAs also serve as regulators of several muscle regeneration,apoptosis,and inflammatory pathways.This study shows the significance of studying miRNAs in such rare cases in a larger cohort to progress in several intervention treatments utilizing miRNAs.展开更多
The online version of the original article can be found at:https://www.sciopen.com/article/10.26599/JOTO.2025.9540018 Erratum to Journal of Otology,2025,20(2):123-126.https://doi.org/10.26599/JOTO.2025.9540018 The sur...The online version of the original article can be found at:https://www.sciopen.com/article/10.26599/JOTO.2025.9540018 Erratum to Journal of Otology,2025,20(2):123-126.https://doi.org/10.26599/JOTO.2025.9540018 The surnames and given names of these authors are reversed:Saro-Buendía Miguel,Andresen-Lorca Belén,Pérez-García Alberto,Llópez Carratala Nacho,Carreres Polo Joan,Armengot Carceller Miguel,Perolada Valmaña Jose María.It should be Miguel Saro-Buendía,Belén Andresen-Lorca,Alberto Pérez-García,Nacho Llópez Carratala,Joan Carreres Polo,Miguel Armengot Carceller,Jose María Perolada Valmaña.展开更多
Osteoradionecrosis of the temporal bone(ORN-TB)is usually controlled with conservative measures.However,a temporal bone resection may be required in unresponsive cases.The reconstruction of the resulting defects may b...Osteoradionecrosis of the temporal bone(ORN-TB)is usually controlled with conservative measures.However,a temporal bone resection may be required in unresponsive cases.The reconstruction of the resulting defects may be challenging because of the radiation damage to regional tissues.As a result,distant free flaps may be an optimal choice.For instance,the gracilis muscular free flap(GMFF)has consistent vascular anatomy and can be used to reconstruct small defects.We report three cases of uncontrolled ORN-TB requiring an extensive temporal bone resection followed by vascularized obliteration with a GMFF.The patients reported complete control of the main otologic symptoms(otorrhea,otalgia,and aural fullness)and optimal functional and aesthetic outcomes.Finally,the patients reported significant improvement in quality of life despite early postoperative complications.To our knowledge,the GMFF had not been used to obliterate temporal bone defects in patients with ORN-TB.展开更多
OBJECTIVE: To identify global research trends in stem cell transplantation for treating Duchenne muscular dystrophy using a bibliometric analysis of Web of Science. DATA RETRIEVAL: We performed a bibliometric analys...OBJECTIVE: To identify global research trends in stem cell transplantation for treating Duchenne muscular dystrophy using a bibliometric analysis of Web of Science. DATA RETRIEVAL: We performed a bibliometric analysis of studies on stem cell transplantation for treating Duchenne muscular dystrophy from 2002 to 2011 retrieved from Web of Science. SELECTION CRITERIA: Inclusion criteria: (a) peer-reviewed published articles on stem cell transplantation for treating Duchenne muscular dystrophy indexed in Web of Science; (b) original research articles, reviews, meeting abstracts, proceedings papers, book chapters, editorial material, and news items; and (c) publication between 2002 and 2011. Exclusion criteria: (a) articles that required manual searching or telephone access; (b) documents that were not published in the public domain; and (c) corrected papers. MAIN OUTCOME MEASURES: (1)Annual publication output; (2) distribution according to subject areas; (3) distribution according to journals; (4) distribution according to country; (5) distribution according to institution; (6) distribution according to institution in China; (7) distribution according to institution that cooperated with Chinese institutions; (8) top-cited articles from 2002 to 2006; (9) top-cited articles from 2007 to 2011. RESULTS: A total of 318 publications on stem cell transplantation for treating Duchenne muscular dystrophy were retrieved from Web of Science from 2002 to 2011, of which almost half derived from American authors and institutes. The number of publications has gradually increased over the past 10 years. Most papers appeared in journals with a focus on gene and molecular research, such as Molecular Therapy, Neuromuscular Disorders, and PLoS One. The 10 most-cited papers from 2002 to 2006 were mostly about different kinds of stem cell transplantation for muscle regeneration, while the 10 most-cited papers from 2007 to 2011 were mostly about new techniques of stem cell transplantation for treating Duchenne muscular dystrophy. CONCLUSION: The publications on stem cell transplantation for treating Duchenne muscular dystrophy were relatively few. It also needs more research to confirm that stem cell therapy is a reliable treatment for Duchenne muscular dystrophy.展开更多
[ Objective] The aim of this experiment was to explore the effects of different rearing modes on muscle histological traits and muscle ten demess and to provide theoretical basis for regulating chicken meat quality. [...[ Objective] The aim of this experiment was to explore the effects of different rearing modes on muscle histological traits and muscle ten demess and to provide theoretical basis for regulating chicken meat quality. [ Method] The effects of outdoor rearing, indoor rearing and cage rea ring modes on the muscular histological traits and meat tenderness of Hetian chicken at the age of 8 weeks, 12 weeks and 16 weeks were re searched. [Result] The results showed that the breast and thigh muscle fibre diameter and muscle shear force of outdoor rearing chicken were sig nificently higher than that of cage rearing chicken ( P 〈 0.05), and muscle fibre density was significantly lower than that of cage rearing chicken ( P 〈 0.05). With aging, the muscle fibre diameter and shear force increased and muscle fibre density decreased ( P 〈 0.05). The muscle fibre di ameter and shear force of male were higher than that of female. The correlation analysis showed that the breast muscle shear force had a signifi cantly positive relation with fibre diameter and negative relation with fibre density ( P 〈 0.05), but thigh muscle shear force had an insignificantly pos itive relation with fibre diameter and fibre density. [ Condusion] Muscular histological traits varied in different rearing modes, and the outdoor rearing promoted the muscular fibre development and increased the muscular shear force.展开更多
[Objective] This study aimed to investigate the characteristics of deposition of inosine monophosphate (IMP) and intramuscular fat (IMF) in muscles of Jinghai yellow chickens and its crossbred.[Method] The charact...[Objective] This study aimed to investigate the characteristics of deposition of inosine monophosphate (IMP) and intramuscular fat (IMF) in muscles of Jinghai yellow chickens and its crossbred.[Method] The characteristics of IMP and IMF deposition of 112-day-old Jinghai yellow chickens (J×J) and its two different 70-day- old crossbreeds (J×B and B×B) were analyzed. The IMP content in breast muscle and leg muscle were determined by HPLC. [Result] The contents of IMP and cor- rected inosine monophosphate (IMPc) in breast muscle were significantly or ex- tremely significantly higher than that in leg muscle of the chickens in the three groups whether in male or female chickens (P〈0.05 or P〈0.01). There were no sig- nificant difference in the contents of IMP and IMPc between hens and roosters (P〉 0.05). The fresh degree of breast muscle and leg muscle was 96,11%-98.16% and 87.22%-93.07%, respectively. And the fresh degree of breast muscle was higher than that of leg muscle. In the three groups, the IMF content in leg muscle was significantly higher than that in breast muscle whether in male or female chickens (P〈0.05). The contents of IMF in breast muscle and leg muscle were 0.36%-0.75% and 1.84%-2.38%, respectively. The iMP content in breast muscle of chickens in Bx J group was extremely significantly higher than that in breast muscle of chickens in JxJ group (P〈0.01), but the contents of IMPc and iMF of breast muscle and leg muscle of the chickens in the three groups had no significant difference (P〉0.05). [Conclusion] To sum up, the freshness and flavor significantly differ between the breast muscle and leg muscle of chickens, but show no significant difference among the three groups.展开更多
Objective' To study the muscular histological traits and their relationship with meat tenderness in local broilers and provide a theoretical basis for promoting meat quality of broiler. [Methed] The diameter and dens...Objective' To study the muscular histological traits and their relationship with meat tenderness in local broilers and provide a theoretical basis for promoting meat quality of broiler. [Methed] The diameter and density of muscle fiber of three local varieties of chicken (Beijing Fatty broil- er, Fujian Hetian broiler and Taining Black broiler) were detected at the age of 8 weeks, 12 weeks and 16 weeks. And the differences in the diame- ter and density of muscle fiber as well as their relationship with meat tenderness were respectively analyzed with SAS software. [ Resultl Fatty broil- er had the smallest muscle fiber diameter while Hetian broiler the largest; Fatty broiler had the highest muscle fiber density while Hetian broiler the lowest Hetian broiler had the highest muscle shear force of leg muscle while Black broiler the lowest ( P 〈0.05) ; Black broiler had the highest mus- cle shear force of breast muscle while Fatty broiler the lowest (P〈0.05). The correlation analysis showed that the shear force of breast muscle and leg muscle had significantly positive relation with fiber diameter and significantly negative relation with fiber density ( P 〈 0.05). [ Conclusion] Muscu- lar histological traits varied in different local broilers, and the muscular shear force had significantly relation with fiber diameter and density.展开更多
Due to their relative abundance,stable biological properties and excellent reproductive activity,umbilical cord mesenchymal stem cells have previously been utilized for the treatment of Duchenne muscular dystrophy,whi...Due to their relative abundance,stable biological properties and excellent reproductive activity,umbilical cord mesenchymal stem cells have previously been utilized for the treatment of Duchenne muscular dystrophy,which is a muscular atrophy disease.Three patients who were clinically and pathologically diagnosed with Duchenne muscular dystrophy were transplanted with umbilical cord mesenchymal stem cells by intravenous infusion,in combination with multi-point intramuscular injection.They were followed up for 12 months after cell transplantation.Results showed that clinical symptoms significantly improved,daily living activity and muscle strength were enhanced,the sero-enzyme,electromyogram,and MRI scans showed improvement,and dystrophin was expressed in the muscle cell membrane.Hematoxylin-eosin staining of a muscle biopsy revealed that muscle fibers were well arranged,fibrous degeneration was alleviated,and fat infiltration was improved.These pieces of evidence suggest that umbilical cord mesenchymal stem cell transplantation can be considered as a new regimen for Duchenne muscular dystrophy.展开更多
Visceral myopathy is one of the causes of chronic intestinal pseudo-obstruction. Most cases pathologically reveal degenerative changes of myocytes or muscularis propia atrophy and fibrosis. Abnormal layering of muscul...Visceral myopathy is one of the causes of chronic intestinal pseudo-obstruction. Most cases pathologically reveal degenerative changes of myocytes or muscularis propia atrophy and fibrosis. Abnormal layering of muscularis propria is extremely rare. We report a case of a 9-mo-old Thai male baby who presented with chronic intestinal pseudo-obstruction. Histologic findings showed abnormal layering of small intestinal muscularis propria with an additional oblique layer and aberrant muscularization in serosa. The patient also had a short small bowel without malrotation, brachydactyly,and absence of the 2nd to 4th middle phalanges of both hands. The patient was treated with cisapride and combined parenteral and enteral nutritional support.He had gradual clinical improvement and gained body weight. Subsequently, the parenteral nutrition was discontinued. The previously reported cases are reviewed and discussed.展开更多
Infantile-onset spinal muscular atrophy is the quintessential example of a disorder characterized by a predominantly neurodegenerative phenotype that nevertheless stems from perturbations in a housekeeping protein.Res...Infantile-onset spinal muscular atrophy is the quintessential example of a disorder characterized by a predominantly neurodegenerative phenotype that nevertheless stems from perturbations in a housekeeping protein.Resulting from low levels of the Survival of Motor Neuron(SMN)protein,spinal muscular atrophy manifests mainly as a lower motor neuron disease.Why this is so and whether other cell types contribute to the classic spinal muscular atrophy phenotype continue to be the subject of intense investigation and are only now gaining appreciation.Yet,what is emerging is sometimes as puzzling as it is instructive,arguing for a careful re-examination of recent study outcomes,raising questions about established dogma in the field and making the case for a greater focus on milder spinal muscular atrophy models as tools to identify key mechanisms driving selective neuromuscular dysfunction in the disease.This review examines the evidence for novel molecular and cellular mechanisms that have recently been implicated in spinal muscular atrophy,highlights breakthroughs,points out caveats and poses questions that ought to serve as the basis of new investigations to better understand and treat this and other more common neurodegenerative disorders.展开更多
Segmental arterial mediolysis (SAM) is an uncommon non-inflammatory iatrogenic arteriopathy caused by alpha-1 adrenergic agonists or Beta-2 agonists able to release norepinephrine from the peripheral nervous system. C...Segmental arterial mediolysis (SAM) is an uncommon non-inflammatory iatrogenic arteriopathy caused by alpha-1 adrenergic agonists or Beta-2 agonists able to release norepinephrine from the peripheral nervous system. Causative agents include adrenergic agonists used to control blood pressure, B-2 tocolytic agonists, and ractopamine used as a repartitioning agent in animal husbandry. The liberated norepinephrine both injures and stimulates a robust reparative response in the muscular arteries in the abdomen, brain base, and coronary arteries. This response may be augmented by endothelin-1 formed in the arterial adventitia. Three types of arterial lesions develop in the injurious stage: 1) apoptotic induced mediolysis, 2) separation of the outer media from the adventitia and 3) the formation of arterial gaps. The latter enlarge, particularly in elderly patients, to form gap-aneurysms complicated by dissections and dissecting an- eurysms that when ruptured cause the calamitous hemorrhages that clinically announce SAM. The other types of injury remain clinically silent but with repair develop sequelae and can metamorphose into fibromuscular dysplasia. The sequelae are mainly asymptomatic but may cause arterial stenosis and ischemic lesions. The definitive diagnosis of SAM re- quires histological conformation but misinterpreta- tion of smooth muscle vacuolar change has caused di- agnostic errors. Muscular artery cystic necrosis a newly named non-inflammatory muscular artery ar- teriopathy may be confused with SAM both clinically and pathologically. This arteriopathy represents the muscular artery equivalent of cystic media necrosis of the elastic arteries since it exhibits similar morphol- ogic features and can occur concomitantly with this entity. Adrenergic agents to counter hemorrhagic shock in SAM are contraindicated since they may intensify injury and create new lesions. The use of norepinehrine antagonists introduces a new, but as yet untested, treatment option for SAM.展开更多
BACKGROUND In Behçet’s disease(BD),very few cases of muscular involvement have been reported previously.The natural history and therapeutic protocol for muscular involvement in BD are obscure due to the low inci...BACKGROUND In Behçet’s disease(BD),very few cases of muscular involvement have been reported previously.The natural history and therapeutic protocol for muscular involvement in BD are obscure due to the low incidence of peripheral neuropathy or myopathy in BD.The purpose of our study was to report a rare case of BD with chronic,focal forms of neuromyopathy and review the relevant literature.CASE SUMMARY We herein report the case of a 54-year-old man who presented with progressive muscular atrophy and weakness of both thighs 2 years after the presentation of the cardinal symptoms of BD.The past medical history,electrophysiological study,neurological examination,blood tests,magnetic resonance imaging study,and histological exam were performed for the differential diagnosis.Relevant literature on muscular involvement in BD was reviewed.Neurological examination revealed that muscular involvement was predominantly localized in the proximal parts of the lower extremities.Heterogeneous enhancement of several thigh muscles was observed on magnetic resonance imaging,which corresponded with the clinical manifestations.Histological study of one of the enhanced muscles showed denervation atrophy of the muscle with superimposed myopathic changes,while electrophysiological studies only suggested denervation.CONCLUSION To our knowledge,this is the first case of neurogenic muscular atrophy with a specific set of clinical,radiological,electrophysiological,and histological findings reported in BD.展开更多
Objective To observe the therapeutic effect of quick-impact Tuina method on treatment of pediatric muscular torticollis.Methods Pushing,kneading,and grasping manipulations combined with traction and flicking method we...Objective To observe the therapeutic effect of quick-impact Tuina method on treatment of pediatric muscular torticollis.Methods Pushing,kneading,and grasping manipulations combined with traction and flicking method were applied at sternocleidomastoid on the affected side for 38 cases of pediatric muscular torticollis.The treatment was given 1 time a day,10 times as a course.The therapeutic effect was evaluated after 3 courses of treatment.Results Thirty-four cases was evaluated as full recovery,3 cases as remarkable effectiveness,1 case as effectiveness,0 case as ineffectiveness,the total effective rate was 100.0%.Conclusion The combined method treating pediatric muscular torticollis regulated tendons and relieved blood stasis,improved muscular spasm,and dispersed mass,so as to enhance and restore the regular neck function with significant therapeutic effect.展开更多
Objective To understand the deletion in the survival motor neuron gene (SMN) of childhood onset spinal muscular atrophy (SMA) in Chinese, and the value of diagnosis of SMA using polymerase chain reaction restric...Objective To understand the deletion in the survival motor neuron gene (SMN) of childhood onset spinal muscular atrophy (SMA) in Chinese, and the value of diagnosis of SMA using polymerase chain reaction restriction fragment length polymorphism (PCR RFLP)method. Methods\ Deletions of SMN gene of exon 7 and 8 in 10 cases of presumed SMA, and 20 normal controls from 6 families and 30 unrelated controls were performed by PCR RFLP analysis. Results\ Deletions of SMN gene detected in 9 of 10 (90%) cases of presumed SMA . No deletions of SMN in the telomere were found in the other members of families and controls.Conclusion\ PCR RFLP is a sensitive, specific and simple method in diagnosis of SMA.\;展开更多
Background:To determine the effectiveness of resistive range of motion exercises in improving muscle strength and functional abilities in Duchenne muscular dystrophy.The study was also aimed to determine if resistive ...Background:To determine the effectiveness of resistive range of motion exercises in improving muscle strength and functional abilities in Duchenne muscular dystrophy.The study was also aimed to determine if resistive range of motion exercises can slow down the progression of the disease.Methods:A seven-year-old male child was diagnosed with Duchenne muscle dystrophy presented to outpatient physiotherapy clinic.The patient was presented with difficulty in stair climbing,sitting up from the floor,fatigue,and muscle weakness specifically weakness in the proximal limb muscles.The progressive resistive range of motion training was implemented for four years to improve muscle strength and functional abilities.The medical research council grading scale,north ambulatory assessment scale,and creatine kinase were used to evaluate muscle strength,functional abilities,and creatine kinase levels.Results:The muscular strength and functional abilities did not improve after four years of exercise training.The creatine kinase levels were decreased over the period of four years.Conclusion:Resistive range of motion exercises are helpful in maintaining the muscular strength and functional abilities in Duchenne muscular dystrophy.展开更多
基金supported by the Collaborative Innovation Center for Clinical and Translational Science by Chinese Ministry of Education&Shanghai,No.CCTS-2022205the“Double World-Class Project”of Shanghai Jiaotong University School of Medicine(both to JZ)。
文摘Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle weakness.It is one of the most common genetic causes of mortality among infants aged less than 2 years.Biomarker research is currently receiving more attention,and new candidate biomarkers are constantly being discovered.This review initially discusses the evaluation methods commonly used in clinical practice while briefly outlining their respective pros and cons.We also describe recent advancements in research and the clinical significance of molecular biomarkers for spinal muscular atrophy,which are classified as either specific or non-specific biomarkers.This review provides new insights into the pathogenesis of spinal muscular atrophy,the mechanism of biomarkers in response to drug-modified therapies,the selection of biomarker candidates,and would promote the development of future research.Furthermore,the successful utilization of biomarkers may facilitate the implementation of gene-targeting treatments for patients with spinal muscular atrophy.
基金supported by the National Key R&D Program of China,No.2021YFA0805200(to SY)the National Natural Science Foundation of China,No.31970954(to SY)two grants from the Department of Science and Technology of Guangdong Province,Nos.2021ZT09Y007,2020B121201006(both to XJL)。
文摘Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy patients.These aggregates alter protein-protein interactions and compromise transcriptional activity.In this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic factor.Overexpressio n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor aggregation.Conversely.knocking down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor aggregation.Our findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy.
文摘Duchenne muscular dystrophy (DMD) is a hereditary, progressive muscular disorder inherited in an X-linked recessive pattern (Xp21). It typically manifests in childhood and follows a severe, rapid progression. Only males are affected, while females are usually carriers. Given the genetic nature of DMD, genetic counseling is an essential service for individuals affected by or at risk of carrying the disease. This service provides not only crucial medical information but also psychosocial support and ongoing management for both patients and their families. Since the discovery of the dystrophin gene in 1987, advancements in molecular genetics have made it possible to precisely identify the genes responsible for many neuromuscular diseases. These developments have revolutionized diagnosis, prognosis, and most importantly, genetic counseling, offering significant benefits for both patients and their families. To highlight the significance of these advancements, this case report focuses on a 10-year-old boy (Y) diagnosed with DMD. It emphasizes the familial nature of the disease, with Y’s two brothers, three cousins, and two maternal uncles also affected, underscoring the inherited pattern of DMD. This reinforces the critical need for early intervention, particularly in regions with high consanguinity, such as North Africa and the Middle East, where genetic counseling and prenatal diagnosis are even more essential. Additionally, the report explores the clinical presentation, diagnostic findings, and promising emerging treatments, including RNA-based therapies, which may play a key role in the future management of DMD. In light of the above, this study underscores the importance of prenatal diagnosis and genetic counseling, particularly in regions like Morocco, where consanguinity rates are notably high. By focusing on preconception care and early genetic intervention, families can be better informed, leading to more effective disease management and support.
文摘Objectives:As the Duchenne Muscular Dystrophy(DMD)is a progressive neuromuscular disorder frequently associated with cardiac dysfunction,this study aimed to evaluate the influence of beta-blocker therapy on cardiac autonomic modulation in adolescents withDMDby analyzing heart rate variability(HRV)indices in patients with and without betablockers.Methods:A cross-sectional study was conducted with 90 participants divided into three groups:(1)participants with DMD receiving beta-blocker therapy(DMDB,n=30),(2)participants with DMD without beta-blocker therapy(GMDM,n=30),and(3)age-and sex-matched typically developing participants(GDT,n=30).HRV was assessed using validated beat-to-beat heart rate monitoring(RS800CX,Polar)under controlled conditions.Linear and non-linear HRV indices(including Detrended Fluctuation Analysis and Symbolic Dynamics)were analysed using Kubios HRV software.Results:DMD patients exhibited autonomic impairment,characterized by decreased HRV,increased sympathetic dominance,and reduced parasympathetic modulation.Betablocker therapy was associated with significantly higher Mean Beat-to-beat interval(RR)and lower Mean Heart Rate(HR)compared to the non-beta-blocker DMD group,with values approaching those observed in typically developing participants.Non-linear indices suggested thatDMDpatients receiving beta-blockers demonstrated increased HRV complexity and fractal properties compared to those not receiving beta-blockers,although differences remained between the DMD and control groups.Conclusions:Autonomic dysfunction in DMD is characterized by reduced HRV and altered sympathovagal balance.In our results,beta-blocker therapy was associated with improved HRV and enhanced autonomic control.These findings highlight the potential cardioprotective role of betablockers in DMD management and emphasize the need for further research into optimizing autonomic function in DMD.
文摘BACKGROUND Duchenne muscular dystrophy(DMD)is a neuromuscular disorder caused by mutations in the dystrophin gene.DMD is reported to coexist with other comorbidities,although the occurrence of the triad,autism spectrum disorder(ASD),and epilepsy is very rare.Indeed,only one case of the triad has currently been reported.Here,we present a detailed case report of a ten-year-old boy with DMD,ASD,and epilepsy.We also investigated the dysregulation of miRNAs in this unusual triad(represented as DMD++)compared with a healthy individual and a DMD patient(represented as DMD+)without autism.AIM To understand the differential expression of miRNAs in rare comorbid DMD cases.METHODS The Sequin Form Board test,Gesell's drawing test,multiplex ligation probe amplification,and Vineland Social Maturity Scale were applied to confirm the DMD and ASD.Total RNA was isolated from samples using TRIzol.cDNA was synthesized using the Mir-X^(TM)miRNA First-Strand Synthesis kit.qRT-PCR was performed using SYBR Advantage qPCR Premix.The results were statistically analyzed using one-way analysis of variance with Tukey's ttest.RESULTS miR-146a-5p and miR-132-5p showed significant downregulation in both patient samples.miR-199a-5p and miR-146a-3p showed no change in expression between the diseased and controls.miR-132-3p showed downregulation only in the DMD+sample(0.21±0.04).The decrease in miR-132-3p can result in failed silencing of the phosphatase and tensin homolog-mediated apoptotic pathway,leading to severe skeletal muscle atrophy.Here,the downregulation of miR-132-3p in DMD+is consistent with severe muscle loss and higher disease progression than that in DMD++.DMD++has slower disease progression,and the expression of miRNA involved in inflammatory and apoptotic responses is more similar to that of the control.CONCLUSION Our study shows marked difference in miRNA expression in this rare case of DMD with autism and epilepsy.These miRNAs also serve as regulators of several muscle regeneration,apoptosis,and inflammatory pathways.This study shows the significance of studying miRNAs in such rare cases in a larger cohort to progress in several intervention treatments utilizing miRNAs.
文摘The online version of the original article can be found at:https://www.sciopen.com/article/10.26599/JOTO.2025.9540018 Erratum to Journal of Otology,2025,20(2):123-126.https://doi.org/10.26599/JOTO.2025.9540018 The surnames and given names of these authors are reversed:Saro-Buendía Miguel,Andresen-Lorca Belén,Pérez-García Alberto,Llópez Carratala Nacho,Carreres Polo Joan,Armengot Carceller Miguel,Perolada Valmaña Jose María.It should be Miguel Saro-Buendía,Belén Andresen-Lorca,Alberto Pérez-García,Nacho Llópez Carratala,Joan Carreres Polo,Miguel Armengot Carceller,Jose María Perolada Valmaña.
文摘Osteoradionecrosis of the temporal bone(ORN-TB)is usually controlled with conservative measures.However,a temporal bone resection may be required in unresponsive cases.The reconstruction of the resulting defects may be challenging because of the radiation damage to regional tissues.As a result,distant free flaps may be an optimal choice.For instance,the gracilis muscular free flap(GMFF)has consistent vascular anatomy and can be used to reconstruct small defects.We report three cases of uncontrolled ORN-TB requiring an extensive temporal bone resection followed by vascularized obliteration with a GMFF.The patients reported complete control of the main otologic symptoms(otorrhea,otalgia,and aural fullness)and optimal functional and aesthetic outcomes.Finally,the patients reported significant improvement in quality of life despite early postoperative complications.To our knowledge,the GMFF had not been used to obliterate temporal bone defects in patients with ORN-TB.
基金supported by the Key TechnologiesR & D Program of Liaoning Province,No.2008225009.
文摘OBJECTIVE: To identify global research trends in stem cell transplantation for treating Duchenne muscular dystrophy using a bibliometric analysis of Web of Science. DATA RETRIEVAL: We performed a bibliometric analysis of studies on stem cell transplantation for treating Duchenne muscular dystrophy from 2002 to 2011 retrieved from Web of Science. SELECTION CRITERIA: Inclusion criteria: (a) peer-reviewed published articles on stem cell transplantation for treating Duchenne muscular dystrophy indexed in Web of Science; (b) original research articles, reviews, meeting abstracts, proceedings papers, book chapters, editorial material, and news items; and (c) publication between 2002 and 2011. Exclusion criteria: (a) articles that required manual searching or telephone access; (b) documents that were not published in the public domain; and (c) corrected papers. MAIN OUTCOME MEASURES: (1)Annual publication output; (2) distribution according to subject areas; (3) distribution according to journals; (4) distribution according to country; (5) distribution according to institution; (6) distribution according to institution in China; (7) distribution according to institution that cooperated with Chinese institutions; (8) top-cited articles from 2002 to 2006; (9) top-cited articles from 2007 to 2011. RESULTS: A total of 318 publications on stem cell transplantation for treating Duchenne muscular dystrophy were retrieved from Web of Science from 2002 to 2011, of which almost half derived from American authors and institutes. The number of publications has gradually increased over the past 10 years. Most papers appeared in journals with a focus on gene and molecular research, such as Molecular Therapy, Neuromuscular Disorders, and PLoS One. The 10 most-cited papers from 2002 to 2006 were mostly about different kinds of stem cell transplantation for muscle regeneration, while the 10 most-cited papers from 2007 to 2011 were mostly about new techniques of stem cell transplantation for treating Duchenne muscular dystrophy. CONCLUSION: The publications on stem cell transplantation for treating Duchenne muscular dystrophy were relatively few. It also needs more research to confirm that stem cell therapy is a reliable treatment for Duchenne muscular dystrophy.
文摘[ Objective] The aim of this experiment was to explore the effects of different rearing modes on muscle histological traits and muscle ten demess and to provide theoretical basis for regulating chicken meat quality. [ Method] The effects of outdoor rearing, indoor rearing and cage rea ring modes on the muscular histological traits and meat tenderness of Hetian chicken at the age of 8 weeks, 12 weeks and 16 weeks were re searched. [Result] The results showed that the breast and thigh muscle fibre diameter and muscle shear force of outdoor rearing chicken were sig nificently higher than that of cage rearing chicken ( P 〈 0.05), and muscle fibre density was significantly lower than that of cage rearing chicken ( P 〈 0.05). With aging, the muscle fibre diameter and shear force increased and muscle fibre density decreased ( P 〈 0.05). The muscle fibre di ameter and shear force of male were higher than that of female. The correlation analysis showed that the breast muscle shear force had a signifi cantly positive relation with fibre diameter and negative relation with fibre density ( P 〈 0.05), but thigh muscle shear force had an insignificantly pos itive relation with fibre diameter and fibre density. [ Condusion] Muscular histological traits varied in different rearing modes, and the outdoor rearing promoted the muscular fibre development and increased the muscular shear force.
基金Supported by the Science and Technology Supporting Project (Agriculture) of Jiangsu Province (BE2011452)the Special Fund Project of the National Broiler Industry Technology System (CARS-42-G23)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)~~
文摘[Objective] This study aimed to investigate the characteristics of deposition of inosine monophosphate (IMP) and intramuscular fat (IMF) in muscles of Jinghai yellow chickens and its crossbred.[Method] The characteristics of IMP and IMF deposition of 112-day-old Jinghai yellow chickens (J×J) and its two different 70-day- old crossbreeds (J×B and B×B) were analyzed. The IMP content in breast muscle and leg muscle were determined by HPLC. [Result] The contents of IMP and cor- rected inosine monophosphate (IMPc) in breast muscle were significantly or ex- tremely significantly higher than that in leg muscle of the chickens in the three groups whether in male or female chickens (P〈0.05 or P〈0.01). There were no sig- nificant difference in the contents of IMP and IMPc between hens and roosters (P〉 0.05). The fresh degree of breast muscle and leg muscle was 96,11%-98.16% and 87.22%-93.07%, respectively. And the fresh degree of breast muscle was higher than that of leg muscle. In the three groups, the IMF content in leg muscle was significantly higher than that in breast muscle whether in male or female chickens (P〈0.05). The contents of IMF in breast muscle and leg muscle were 0.36%-0.75% and 1.84%-2.38%, respectively. The iMP content in breast muscle of chickens in Bx J group was extremely significantly higher than that in breast muscle of chickens in JxJ group (P〈0.01), but the contents of IMPc and iMF of breast muscle and leg muscle of the chickens in the three groups had no significant difference (P〉0.05). [Conclusion] To sum up, the freshness and flavor significantly differ between the breast muscle and leg muscle of chickens, but show no significant difference among the three groups.
文摘Objective' To study the muscular histological traits and their relationship with meat tenderness in local broilers and provide a theoretical basis for promoting meat quality of broiler. [Methed] The diameter and density of muscle fiber of three local varieties of chicken (Beijing Fatty broil- er, Fujian Hetian broiler and Taining Black broiler) were detected at the age of 8 weeks, 12 weeks and 16 weeks. And the differences in the diame- ter and density of muscle fiber as well as their relationship with meat tenderness were respectively analyzed with SAS software. [ Resultl Fatty broil- er had the smallest muscle fiber diameter while Hetian broiler the largest; Fatty broiler had the highest muscle fiber density while Hetian broiler the lowest Hetian broiler had the highest muscle shear force of leg muscle while Black broiler the lowest ( P 〈0.05) ; Black broiler had the highest mus- cle shear force of breast muscle while Fatty broiler the lowest (P〈0.05). The correlation analysis showed that the shear force of breast muscle and leg muscle had significantly positive relation with fiber diameter and significantly negative relation with fiber density ( P 〈 0.05). [ Conclusion] Muscu- lar histological traits varied in different local broilers, and the muscular shear force had significantly relation with fiber diameter and density.
基金a grant by Key Projects of Liaoning Province, No. 2008225009
文摘Due to their relative abundance,stable biological properties and excellent reproductive activity,umbilical cord mesenchymal stem cells have previously been utilized for the treatment of Duchenne muscular dystrophy,which is a muscular atrophy disease.Three patients who were clinically and pathologically diagnosed with Duchenne muscular dystrophy were transplanted with umbilical cord mesenchymal stem cells by intravenous infusion,in combination with multi-point intramuscular injection.They were followed up for 12 months after cell transplantation.Results showed that clinical symptoms significantly improved,daily living activity and muscle strength were enhanced,the sero-enzyme,electromyogram,and MRI scans showed improvement,and dystrophin was expressed in the muscle cell membrane.Hematoxylin-eosin staining of a muscle biopsy revealed that muscle fibers were well arranged,fibrous degeneration was alleviated,and fat infiltration was improved.These pieces of evidence suggest that umbilical cord mesenchymal stem cell transplantation can be considered as a new regimen for Duchenne muscular dystrophy.
基金Supported by Faculty of Medicine,Ramathibodi Hospital,Mahidol University,Thailand
文摘Visceral myopathy is one of the causes of chronic intestinal pseudo-obstruction. Most cases pathologically reveal degenerative changes of myocytes or muscularis propia atrophy and fibrosis. Abnormal layering of muscularis propria is extremely rare. We report a case of a 9-mo-old Thai male baby who presented with chronic intestinal pseudo-obstruction. Histologic findings showed abnormal layering of small intestinal muscularis propria with an additional oblique layer and aberrant muscularization in serosa. The patient also had a short small bowel without malrotation, brachydactyly,and absence of the 2nd to 4th middle phalanges of both hands. The patient was treated with cisapride and combined parenteral and enteral nutritional support.He had gradual clinical improvement and gained body weight. Subsequently, the parenteral nutrition was discontinued. The previously reported cases are reviewed and discussed.
基金Research on SMA in the Monani lab is funded by NIH(R21 NS099921,R01 NS104218)Cure SMA and Roche Inc(to URM).
文摘Infantile-onset spinal muscular atrophy is the quintessential example of a disorder characterized by a predominantly neurodegenerative phenotype that nevertheless stems from perturbations in a housekeeping protein.Resulting from low levels of the Survival of Motor Neuron(SMN)protein,spinal muscular atrophy manifests mainly as a lower motor neuron disease.Why this is so and whether other cell types contribute to the classic spinal muscular atrophy phenotype continue to be the subject of intense investigation and are only now gaining appreciation.Yet,what is emerging is sometimes as puzzling as it is instructive,arguing for a careful re-examination of recent study outcomes,raising questions about established dogma in the field and making the case for a greater focus on milder spinal muscular atrophy models as tools to identify key mechanisms driving selective neuromuscular dysfunction in the disease.This review examines the evidence for novel molecular and cellular mechanisms that have recently been implicated in spinal muscular atrophy,highlights breakthroughs,points out caveats and poses questions that ought to serve as the basis of new investigations to better understand and treat this and other more common neurodegenerative disorders.
文摘Segmental arterial mediolysis (SAM) is an uncommon non-inflammatory iatrogenic arteriopathy caused by alpha-1 adrenergic agonists or Beta-2 agonists able to release norepinephrine from the peripheral nervous system. Causative agents include adrenergic agonists used to control blood pressure, B-2 tocolytic agonists, and ractopamine used as a repartitioning agent in animal husbandry. The liberated norepinephrine both injures and stimulates a robust reparative response in the muscular arteries in the abdomen, brain base, and coronary arteries. This response may be augmented by endothelin-1 formed in the arterial adventitia. Three types of arterial lesions develop in the injurious stage: 1) apoptotic induced mediolysis, 2) separation of the outer media from the adventitia and 3) the formation of arterial gaps. The latter enlarge, particularly in elderly patients, to form gap-aneurysms complicated by dissections and dissecting an- eurysms that when ruptured cause the calamitous hemorrhages that clinically announce SAM. The other types of injury remain clinically silent but with repair develop sequelae and can metamorphose into fibromuscular dysplasia. The sequelae are mainly asymptomatic but may cause arterial stenosis and ischemic lesions. The definitive diagnosis of SAM re- quires histological conformation but misinterpreta- tion of smooth muscle vacuolar change has caused di- agnostic errors. Muscular artery cystic necrosis a newly named non-inflammatory muscular artery ar- teriopathy may be confused with SAM both clinically and pathologically. This arteriopathy represents the muscular artery equivalent of cystic media necrosis of the elastic arteries since it exhibits similar morphol- ogic features and can occur concomitantly with this entity. Adrenergic agents to counter hemorrhagic shock in SAM are contraindicated since they may intensify injury and create new lesions. The use of norepinehrine antagonists introduces a new, but as yet untested, treatment option for SAM.
文摘BACKGROUND In Behçet’s disease(BD),very few cases of muscular involvement have been reported previously.The natural history and therapeutic protocol for muscular involvement in BD are obscure due to the low incidence of peripheral neuropathy or myopathy in BD.The purpose of our study was to report a rare case of BD with chronic,focal forms of neuromyopathy and review the relevant literature.CASE SUMMARY We herein report the case of a 54-year-old man who presented with progressive muscular atrophy and weakness of both thighs 2 years after the presentation of the cardinal symptoms of BD.The past medical history,electrophysiological study,neurological examination,blood tests,magnetic resonance imaging study,and histological exam were performed for the differential diagnosis.Relevant literature on muscular involvement in BD was reviewed.Neurological examination revealed that muscular involvement was predominantly localized in the proximal parts of the lower extremities.Heterogeneous enhancement of several thigh muscles was observed on magnetic resonance imaging,which corresponded with the clinical manifestations.Histological study of one of the enhanced muscles showed denervation atrophy of the muscle with superimposed myopathic changes,while electrophysiological studies only suggested denervation.CONCLUSION To our knowledge,this is the first case of neurogenic muscular atrophy with a specific set of clinical,radiological,electrophysiological,and histological findings reported in BD.
文摘Objective To observe the therapeutic effect of quick-impact Tuina method on treatment of pediatric muscular torticollis.Methods Pushing,kneading,and grasping manipulations combined with traction and flicking method were applied at sternocleidomastoid on the affected side for 38 cases of pediatric muscular torticollis.The treatment was given 1 time a day,10 times as a course.The therapeutic effect was evaluated after 3 courses of treatment.Results Thirty-four cases was evaluated as full recovery,3 cases as remarkable effectiveness,1 case as effectiveness,0 case as ineffectiveness,the total effective rate was 100.0%.Conclusion The combined method treating pediatric muscular torticollis regulated tendons and relieved blood stasis,improved muscular spasm,and dispersed mass,so as to enhance and restore the regular neck function with significant therapeutic effect.
文摘Objective To understand the deletion in the survival motor neuron gene (SMN) of childhood onset spinal muscular atrophy (SMA) in Chinese, and the value of diagnosis of SMA using polymerase chain reaction restriction fragment length polymorphism (PCR RFLP)method. Methods\ Deletions of SMN gene of exon 7 and 8 in 10 cases of presumed SMA, and 20 normal controls from 6 families and 30 unrelated controls were performed by PCR RFLP analysis. Results\ Deletions of SMN gene detected in 9 of 10 (90%) cases of presumed SMA . No deletions of SMN in the telomere were found in the other members of families and controls.Conclusion\ PCR RFLP is a sensitive, specific and simple method in diagnosis of SMA.\;
文摘Background:To determine the effectiveness of resistive range of motion exercises in improving muscle strength and functional abilities in Duchenne muscular dystrophy.The study was also aimed to determine if resistive range of motion exercises can slow down the progression of the disease.Methods:A seven-year-old male child was diagnosed with Duchenne muscle dystrophy presented to outpatient physiotherapy clinic.The patient was presented with difficulty in stair climbing,sitting up from the floor,fatigue,and muscle weakness specifically weakness in the proximal limb muscles.The progressive resistive range of motion training was implemented for four years to improve muscle strength and functional abilities.The medical research council grading scale,north ambulatory assessment scale,and creatine kinase were used to evaluate muscle strength,functional abilities,and creatine kinase levels.Results:The muscular strength and functional abilities did not improve after four years of exercise training.The creatine kinase levels were decreased over the period of four years.Conclusion:Resistive range of motion exercises are helpful in maintaining the muscular strength and functional abilities in Duchenne muscular dystrophy.