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INTRODUCTION: Osteoarthritis (OA) is the most common joint disorder among musculoskeletal conditions. Non-surgical treatment is the standard therapy for knee OA (KOA). Ultrasound therapy is recommended for alleviating pain and dysfunction from OA, but high-quality scientific evidence for its effectiveness in OA treatment is still lacking.Therefore, we want to analyse whether combining conventional physical therapy with low-intensity pulsed ultrasound (LIPUS) can enhance the efficacy of conventional therapy, thus improving symptoms in patients with KOA. METHODS AND ANALYSIS: This randomised controlled trial aims to recruit 200 patients diagnosed with KOA, aged 38 years or above, who meet the clinical diagnostic criteria for KOA. Patients will be randomly assigned in a 1:1 ratio to either a LIPUS treatment group or a sham ultrasound treatment control group. The 2-week treatment will consist of five sessions per week and evaluations will take place at baseline, on the day of the last intervention and 1 month post intervention. The main outcome measures will be the Western Ontario and McMaster Universities' scores. Secondary outcome indicators will be the Numerical Pain Rating Scale, the Lequesne scale, the time up and go test and the range of motion of the knee. An intention-to-treat analysis will be performed for dropouts and missing data. ETHICS AND DISSEMINATION: The study was approved by the ethics committee of Shengjing Hospital of China Medical University (2023PS592K). Findings will be disseminated to participants and made available to peer-reviewed journals. TRIAL REGISTRATION NUMBER: The trial was registered on the Chinese Clinical Trial Registry platform (chictr.org.cn) on 22 March 2023, with the registration ID ChiCTR2300069643.
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Gonarthrose , Ultrasonothérapie , Humains , Gonarthrose/thérapie , Ultrasonothérapie/méthodes , Méthode en double aveugle , Mesure de la douleur , Essais contrôlés randomisés comme sujet , Adulte d'âge moyen , Amplitude articulaire , Résultat thérapeutique , Mâle , Femelle , Adulte , Ondes ultrasonores , Techniques de physiothérapieRÉSUMÉ
Antibacterial hydrogel wound dressings hold great potential in eliminating bacteria and accelerating the healing process. However, it remains a challenge to fabricate hydrogel wound dressings that simultaneously exhibit excellent mechanical and photothermal antibacterial properties. Here we report the development of polydopamine-functionalized graphene oxide (rGO@PDA)/calcium alginate (CA)/Polypyrrole (PPy) cotton fabric-reinforced hydrogels (abbreviated as rGO@PDA/CA/PPy FHs) for tackling bacterial infections. The mechanical properties of hydrogels were greatly enhanced by cotton fabric reinforcement and an interpenetrating structure, while excellent broad-spectrum photothermal antibacterial properties based on the photothermal effect were obtained by incorporating PPy and rGO@PDA. Results indicated that rGO@PDA/CA/PPy FHs exhibited superior tensile strength in both the warp (289 ± 62.1 N) and weft directions (142 ± 23.0 N), similarly to cotton fabric. By incorporating PPy and rGO@PDA, the swelling ratio was significantly decreased from 673.5% to 236.6%, while photothermal conversion performance was significantly enhanced with a temperature elevated to 45.0 °C. Due to the synergistic photothermal properties of rGO@PDA and PPy, rGO@PDA/CA/PPy FHs exhibited excellent bacteria-eliminating efficiency for S. aureus (0.57%) and E. coli (3.58%) after exposure to NIR for 20 min. We believe that the design of fabric-reinforced hydrogels could serve as a guideline for developing hydrogel wound dressings with improved mechanical properties and broad-spectrum photothermal antibacterial properties for infected-wound treatment.
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Purpose: The purpose of this study was to observe, using Footscan analysis, the effect of electromyographic feedback functional electrical stimulation (FES) on the changes in the plantar pressure of drop foot patients. Methods: This case-control study enrolled 34 stroke patients with foot drop. There were 17 cases received FES for 20 min per day, 5 days per week for 4 weeks (the FES group) and the other 17 cases only received basic rehabilitations (the control group). Before and after 4 weeks, the walking speed, spatiotemporal parameters and plantar pressure were measured. Results: After 4 weeks treatments, Both the FES and control groups had increased walking speed and single stance phase percentage, decreased step length symmetry index (SI), double stance phase percentage and start time of the heel after 4 weeks (p < 0.05). The increase in walking speed and decrease in step length SI in the FES group were more significant than the control group after 4 weeks (p < 0.05). The FES group had an increased initial contact phase, decreased SI of the maximal force (Max F) and impulse in the medial heel after 4 weeks (p < 0.05). Conclusion: The advantages of FES were: the improvement of gait speed, step length SI, and the enhancement of propulsion force were more significant. The initial contact phase was closer to the normal range, which implies that the control of ankle dorsiflexion was improved. The plantar dynamic parameters between the two sides of the foot were more balanced than the control group. FES is more effective than basic rehabilitations for stroke patients with foot drop based on current spatiotemporal parameters and plantar pressure results.
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In response to the problem that the traditional lower limb rehabilitation scale assessment method is time-consuming and difficult to use in exoskeleton rehabilitation training, this paper proposes a quantitative assessment method for lower limb walking ability based on lower limb exoskeleton robot training with multimodal synergistic information fusion. The method significantly improves the efficiency and reliability of the rehabilitation assessment process by introducing quantitative synergistic indicators fusing electrophysiological and kinematic level information. First, electromyographic and kinematic data of the lower extremity were collected from subjects trained to walk wearing an exoskeleton. Then, based on muscle synergy theory, a synergistic quantification algorithm was used to construct synergistic index features of electromyography and kinematics. Finally, the electrophysiological and kinematic level information was fused to build a modal feature fusion model and output the lower limb motor function score. The experimental results showed that the correlation coefficients of the constructed synergistic features of electromyography and kinematics with the clinical scale were 0.799 and 0.825, respectively. The results of the fused synergistic features in the K-nearest neighbor (KNN) model yielded higher correlation coefficients ( r = 0.921, P < 0.01). This method can modify the rehabilitation training mode of the exoskeleton robot according to the assessment results, which provides a basis for the synchronized assessment-training mode of "human in the loop" and provides a potential method for remote rehabilitation training and assessment of the lower extremity.
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Dispositif d'exosquelette , Réadaptation après un accident vasculaire cérébral , Humains , Reproductibilité des résultats , Marche à pied/physiologie , Membre inférieur , Algorithmes , Réadaptation après un accident vasculaire cérébral/méthodesRÉSUMÉ
INTRODUCTION: Fibromyalgia (FM) is an unexplained chronic condition characterised by generalised pain, sleep disturbances, autonomic disturbances, anxiety, fatigue and cognitive impairment. FM is a prevalent chronic disease worldwide that imposes a significant burden on individuals and society. Emerging evidence suggests that environmental interventions, such as exposure to hyperbaric oxygen therapy (HBOT), can relieve pain and improve the quality of life in patients with FM. This study will systematically and comprehensively assess the effectiveness and safety of HBOT in patients with FM and provide evidence to support its implementation. We hope that the final review will be helpful in supporting the decision-making processes related to treatment programmes. METHODS AND ANALYSIS: This protocol is reported in accordance with the Preferred Reporting Items for Systematic review and Meta-Analysis Protocols guidelines. Ten key databases, Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE (Excerpt Medica Database), PsycINFO, CINAHL (Cumulative Index to Nursing and Allied Health Literature), PEDro, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, WANFANG and VIP (Chinese Scientific Journal Database), will be searched from inception through December 2022 to identify relevant randomised controlled trials examining the effectiveness of HBOT in patients with FM published in English or Chinese. Two reviewers will independently complete the study screening, selection, and data extraction and assess the risk of bias in the included studies using the 0-10 PEDro Scale. Narrative or quantitative syntheses will be performed and a systematic review and meta-analysis will be performed using Review Manager V.5.3 statistical software. ETHICS AND DISSEMINATION: Ethical approval was not required for this protocol. The results of the final review will be disseminated in a peer--reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42022363672.
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Fibromyalgie , Oxygénation hyperbare , Humains , Fibromyalgie/thérapie , Qualité de vie , Douleur , Fatigue , Revues systématiques comme sujet , Méta-analyse comme sujetRÉSUMÉ
Inflammatory bowel disease (IBD) is a chronic disease with multiple complications during its development, and it is difficult to cure. The aim of this study was to evaluate the alleviating effect of different concentrations of the bioactive peptide IQW (Ile-Gln-Trp) on dextran sodium sulfate (DSS)-induced colitis in mice. For this study, we randomly divided 56 ICR mice into seven groups: the (I) control (CON), (II) dextran sodium sulfate treatment (2.5% DSS), (III) IQW-DSS (20 µg/ml) treatment, (IV) IQW-DSS (40 µg/ml) treatment, (V) IQW-DSS (60 µg/ml) treatment, (VI) IQW-DSS (80 µg/ml) treatment, and (VII) IQW-DSS (100 µg/ml) groups. The results showed that IQW at 60 µg/ml alleviated body weight loss, improved the liver index (p < 0.05), and improved histomorphological and pathological changes in the colon compared to the DSS-treated group. IQW at 60 µg/ml and IQW at 80 µg/ml modified intestinal microbial disorders. In addition, IQW at 60 µg/ml significantly increased butyric acid levels and decreased valeric acid levels, while IQW at 80 µg/ml significantly increased isobutyric acid and isovaleric acid levels. Hence, IQW at a concentration of 60 µg/ml alleviates DSS-induced colitis by enhancing the body's anti-inflammatory ability and regulating intestinal flora and metabolic changes. In the above context, IQW at 60 µg/ml could be a potential candidate for IBD prevention and treatment.
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With the development of photothermal nanomaterials, photothermal therapy based on near-infrared light excitation shows great potential for the bacterial infected wound treatment. At the same time, in order to improve the photothermal antibacterial effect of wound infection and reduce the damage of high temperature and heat to healthy tissue, the targeted bacteria strategy has been gradually applied in wound photothermal therapy. In this paper, several commonly used photothermal nanomaterials as well as their targeted bacterial strategies were introduced, and then their applications in photothermal antibacterial therapy, especially in bacterial infected wounds were described. Besides, the challenges of targeted photothermal antibacterial therapy in the wound healing application were analyzed, and the development of photothermal materials with targeted antibacterial property has prospected in order to provide a new idea for wound photothermal therapy.
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Nanostructures , Infection de plaie , Antibactériens/pharmacologie , Humains , Nanostructures/usage thérapeutique , Staphylococcus aureus , Cicatrisation de plaie , Infection de plaie/thérapieRÉSUMÉ
Melanoma, which originates from neural crest derived melanocytes, causes severe pain and even death to numerous patients. Previous studies reported that Notchless Homolog 1 (NLE1) plays an important role in cell proliferation, transcription and signal transduction. However, the clinical significance and biological behavior of NLE1 in melanoma remain a mystery. Thus, the role of NLE1 in melanoma was investigated in vitro and in vivo. The expression of NLE1 in melanoma was elevated and the expression level was positively correlated with lymphatic metastasis and tumor stage. In addition, NLE1 knockdown by shRNA specifically inhibited proliferation, enhanced the apoptotic sensitivity and hindered migration of melanoma cells in vitro. Mice xenograft model further showed that NLE1 knockdown could inhibit the tumor formation of melanoma in vivo. Additionally, the induction of apoptosis of melanoma cells by NLE1 knockdown required the participation of a series of apoptosis-related proteins. Besides, NLE1 can activate the PI3K/AKT signaling pathway. In summary, NLE1 was involved in the development and progression of melanoma, which may be a novel potential target for molecular therapy of melanoma.
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Prolifération cellulaire/génétique , Régulation de l'expression des gènes tumoraux/génétique , Mélanome/génétique , Mélanome/anatomopathologie , Protéines des microfilaments/génétique , Animaux , Apoptose/génétique , Lignée cellulaire tumorale , Techniques de knock-down de gènes , Humains , Mélanome/métabolisme , Souris , Phosphatidylinositol 3-kinases/génétique , Phosphatidylinositol 3-kinases/métabolisme , Protéines proto-oncogènes c-akt/métabolisme , Tests d'activité antitumorale sur modèle de xénogreffe/méthodesRÉSUMÉ
Parkinson's disease (PD) is the second most common neurodegenerative disorder mainly occurring in the elderly. MicroRNA-155-5p (miR-155-5p) plays a vital role in neurodegenerative disease and has been reported to be regulated by rosmarinic acid (RA). In our previous study, it was found that RA could improve motor function and alleviate inflammatory responses in a mice model of PD. This study aimed to investigate the role of miR-155-5p in RA-treated PD mice. The PD mice model was established by injecting mice with N-methyl-4-phenyl-l,2,3,6-tetrahydropyridine (MPTP) and treated with RA or/and miR-155-5p agomir. The effects of miR-155-5p agomir on motor function, microglial activation, inflammation, apoptosis, and oxidative stress were analyzed by performing a behavioral test, ionized calcium-binding adapter molecule 1 staining, quantitative real-time PCR, Western blot, enzyme-linked immunosorbent assay, tyrosine hydroxylase (TH)-terminal dUTP nick end labeling double staining, TH-cleaved-caspase 3 double staining, and assessment of antioxidative parameters in RA-treated PD mice. The interaction between miR-155-5p and suppressor of cytokine signaling 1/nuclear factor erythroid 2-related factor 2 was validated using dual-luciferase reporter assay. MiR-155-5p up-regulation inhibited the alleviation of motor deficits caused by RA in PD mice, as evidenced by increasing descending time, decreasing limb movement score, increasing the time crossing the beam, and decreasing the times of front limb use. MiR-155-5p up-regulation could elevate microglial activation, inflammation, apoptosis, and oxidative stress in RA-treated PD mice. In conclusion, RA was able to alleviate PD by regulating miR-155-5p, suggesting that miR-155-5p could be used as a therapeutic target for PD treatment.
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microARN , Maladies neurodégénératives , Maladie de Parkinson , Animaux , Apoptose , Cinnamates , Depsides , Inflammation/traitement médicamenteux , Souris , Souris de lignée C57BL , microARN/génétique , microARN/métabolisme , Stress oxydatif ,RÉSUMÉ
The main goal of spinal cord rehabilitation is to restore walking ability and improve walking quality after spinal cord injury (SCI). The spatiotemporal parameters of walking and the parameters of plantar pressure can be obtained using a plantar pressure analysis system. Previous studies have reported step asymmetry in patients with bilateral SCI. However, the asymmetry of other parameters in patients with SCI has not been reported. This was a prospective, cross-sectional study, which included 23 patients with SCI, aged 48.1 ± 14.5 years, and 28 healthy subjects, aged 47.1 ± 9.8 years. All subjects underwent bare foot walking on a plantar pressure measurement device to measure walking speed and spatiotemporal parameters. Compared with healthy subjects, SCI patients had slower walking speed, longer stride time and stance time, larger stance phase percentage, and shorter stride length. The peak pressures under the metatarsal heads and toe were lower in SCI patients than in healthy subjects. In the heel, regional impulse and the contact area percentage in SCI patients were higher than those in healthy subjects. The symmetry indexes of stance time, step length, maximum force, impulse and contact area were increased in SCI patients, indicating a decline in symmetry. The results confirm that the gait quality, including spatiotemporal variables and plantar pressure parameters, and symmetry index were lower in SCI patients compared with healthy subjects. Plantar pressure parameters and symmetry index could be sensitive quantitative parameters to improve gait quality of SCI patients. The protocols were approved by the Clinical Research Ethics Committee of Shengjing Hospital of China Medical University (approval No. 2015PS54J) on August 13, 2015. This trial was registered in the ISRCTN Registry (ISRCTN42544587) on August 22, 2018. Protocol version: 1.0.
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OBJECTIVES: This study aims to explore whether extracorporeal shockwave treatment (ESWT) based on the theory of fascial manipulation (FM) at select treatment points is superior to traditional local ESWT for pain relief in adhesive capsulitis of the shoulder. METHODS: Data from patients with adhesive capsulitis of the shoulder who received weekly ESWT according to fascial manipulation theory (ESWT-FM) or local extracorporeal shockwave treatment (L-ESWT) during a 5-week treatment period were evaluated. Pain-on-movement numeric rating scale (p-NRS) and range of motion (ROM) testing were performed before the treatment period, after the first treatment, and after the fifth treatment. RESULTS: There were significant reductions in pain scores in the ESWT-FM group (p < 0.05) after the first treatment, and after the fifth treatment, both groups had marked, significant improvement (p < 0.05), with a significantly greater reduction in pain (p-NRS) in the ESWT-FM group compared to the L-ESWT group (p < 0.05). There was no significant difference in terms of ROM in the L-ESWT group, while there was slight improvement of forward flexion in the ESWT-FM group after the fifth treatment. CONCLUSIONS: ESWT-FM provided faster pain relief and slightly more notable improvement of function compared with L-ESWT for the patients with adhesive capsulitis of shoulder.
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Bursite , Traitement par ondes de choc extracorporelles , Gestion de la douleur , Mesure de la douleur , Bursite/anatomopathologie , Bursite/physiopathologie , Bursite/thérapie , Femelle , Humains , Mâle , Adulte d'âge moyen , Douleur/anatomopathologie , Douleur/physiopathologie , Études rétrospectivesRÉSUMÉ
There is considerable interest in how the fate of adipose-derived stem cells is determined. Physical stimuli play a crucial role in skeletogenesis and in cartilage repair and regeneration. In the present study, we investigated the comparative and interactive effects of dynamic compression and SRY-related high-mobility group box gene-9 (SOX-9) on chondrogenesis of rabbit adipose-derived stem cells in three-dimensional gradual porous PLGA (polylactic-co-glycolic acid) composite scaffolds. Articular cartilage is stratified into zones delineated by characteristic changes in cellular, matrix, and nutritive components. As a consequence, biochemical and biomechanical properties vary greatly between the different zones, giving the tissue its unique structure and, thus, the ability to cope with extreme loading. The effects on development of the cartilage were examined using a combination of computational modeling to predict alterations in biophysical stimuli, detailed morphometric analysis of 3D digital representations. In addition, early chondrogenic differentiation was assessed via real-time PCR of mRNA expression levels for bone- and cartilage-specific gene markers. Our findings define the important role of dynamic compression combined with SOX-9 overexpression during in vitro generation of tissue-engineering cartilage and suggest that a 3D gradual porous PLGA composite scaffold may benefit articular cartilage tissue engineering in cartilage regeneration for better force distribution.
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Cartilage articulaire/cytologie , Chondrogenèse , Sous-unité alpha du facteur-1 induit par l'hypoxie/génétique , Acide lactique/composition chimique , Cellules souches mésenchymateuses/cytologie , Acide polyglycolique/composition chimique , Facteur de transcription SOX-9/génétique , Structures d'échafaudage tissulaires/composition chimique , Tissu adipeux/cytologie , Animaux , Phénomènes biomécaniques , Cartilage articulaire/physiologie , Cellules cultivées , Cellules souches mésenchymateuses/métabolisme , Copolymère d'acide poly(lactique-co-glycolique) , Lapins , Ingénierie tissulaire/méthodes , Régulation positiveRÉSUMÉ
Neovascularization is required for bone formation and successful fracture healing. In the process of neovascularization, endothelial progenitor cells (EPCs) play an important role and finish vascular repair through reendothelialization to promote successful fracture healing. In this study, we found that dynamic compression can promote the proliferation and capillary-like tube formation of EPCs in the demineralized bone matrix (DBM) scaffold seed. EPCs isolated from the bone marrow of rats have been cultured in DBM scaffolds before dynamic compression and then seeded in the DBM scaffolds under dynamic conditions. The cells/scaffold constructs were subjected to cyclic compression with 5% strain and at 1 Hz for 4 h/day for 7 consecutive days. By using MTT and real-time PCR, we found that dynamic compression can significantly induce the proliferation of EPCs in three-dimensional culture with an even distribution of cells onto DBM scaffolds. Both in vitro and in vivo, the tube formation assays in the scaffolds showed that the loaded EPCs formed significant tube-like structures. These findings suggest that dynamic compression promoted the vasculogenic activities of EPCs seeded in the scaffolds, which would benefit large bone defect tissue engineering.
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Trame osseuse/métabolisme , Prolifération cellulaire , Cellules endothéliales/métabolisme , Mécanotransduction cellulaire , Néovascularisation physiologique , Cellules souches/métabolisme , Ingénierie tissulaire , Structures d'échafaudage tissulaires , Animaux , Bioréacteurs , Technique de déminéralisation de l'os , Cellules cultivées , Cellules endothéliales/transplantation , Cellules endothéliales/ultrastructure , Régulation de l'expression des gènes , Microscopie électronique à balayage , Néovascularisation physiologique/génétique , Pression , ARN messager/métabolisme , Rats , Rat Wistar , Réaction de polymérisation en chaine en temps réel , Transplantation de cellules souches , Cellules souches/ultrastructure , Suidae , Facteurs temps , Ingénierie tissulaire/instrumentation , Ingénierie tissulaire/méthodes , Récepteur-2 au facteur croissance endothéliale vasculaire/génétique , Récepteur-2 au facteur croissance endothéliale vasculaire/métabolisme , Facteur de von Willebrand/génétique , Facteur de von Willebrand/métabolismeRÉSUMÉ
We reported a 23-year-old man who was involved in a high-speed motorcycle accident. He sustained a closed fracture at the right distal femur. The primary fracture happened on February 2008. He underwent open reduction and internal fixation with cloverleaf plate. And one hundred days after the surgery, the proximal screws were pulled-out, but the bone union was not achieved. Treatment consisted of exchanging the cloverleaf plate with a locking compression plate and using an auto-iliac bone graft to fill the nonunion gap. In July 2009, the patient had a sharp pain in the right lower limb. The X-ray revealed that the plate implanted last year was broken, causing a nonunion at the fracture site. Immediately the plate and screws were removed and an intramedullary nail was inserted reversely from the distal femur as well as a 7 cm long bone from the right fibula was extracted and longitudinally split into two pieces to construct cortical bone plates. Then we placed them laterally and medially to fracture site, drilled two holes respectively, and fastened them with suture. We carried on auto-iliac bone grafting with the nonunion bone grafts. The follow-up at 15 months after operation showed that the treatment was successful, X-ray confirmed that there was no rotation and no angular or short deformity. We briefly reviewed the literature regarding such an unusual presentation and discussed in details the possible etiology and the advantages of autologous double-strut fibular grafts to cope with such an intractable situation.
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Plaques orthopédiques , Fibula , Fémur , Ostéosynthèse interne , Fractures osseuses , HumainsRÉSUMÉ
Insulin-like growth factor 2 (IGF2) is a potent mitogenic and survival factor involved in the regulation of growth, development and reproduction in animals. Only one IGF2 gene exists in mammals. Recently, two igf2 genes have been identified in zebrafish, which presumably resulted from gene duplication. However, sequence information of duplicated igf2s and their functional regulation in other teleost fish is still unknown. Here, we report the identification of two igf2 cDNAs in grass carp, Ctenopharyngodon idellus. Like their human ortholog, grass carp igf2a and igf2b mRNAs encoded two structurally distinct mature IGF peptides. Both of them were detected by RT-PCR throughout embryogenesis. Ubiquitous expression of igf2b mRNAs was observed in embryos, whereas igf2a mRNAs were expressed mainly in the notochord and brain with in situ hybridization. In adult fish, igf2b mRNAs were transcribed in multiple tissues, whereas igf2a mRNAs were detected mainly in the liver. Hepatic levels of igf2a and igf2b transcripts were both up-regulated by growth hormone injection. Furthermore, the levels of hepatic igf2a and igf2b mRNAs decreased significantly during starvation and were rebounded rapidly after re-feeding. Our results suggest that duplicated igf2 genes have evolved divergent yet played an overlapping biological role in regulating grass carp growth and development.
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Carpes (poisson)/génétique , Protéines de poisson/génétique , Facteur de croissance IGF-II/génétique , Séquence d'acides aminés , Animaux , Carpes (poisson)/métabolisme , Évolution moléculaire , Gènes dupliqués , Données de séquences moléculaires , Phylogenèse , Alignement de séquencesRÉSUMÉ
Recent studies on comparative genomics have suggested that a round of fish-specific whole genome duplication (3R) in ray-finned fishes might have occurred around 226-316 Mya. Additional genome duplication, specifically in cyprinids, may have occurred more recently after the divergence of the teleosts. The timing of this event, however, is unknown. To address this question, we sequenced four Hox genes from taxa representing the polyploid Cyprinidae fish, common carp (Cyprinus carpio, 2n=100), crucian carp (Carassius auratus auratus, 2n=100), and silver crucian carp (C. auratus gibelio, 2n=156), and then compared them with known sequences from the diploid Cyprinidae fish, blunt snout bream (Megalobrama amblycephala, 2n=48). Our results showed the presence of two distinct Hox duplicates in the genomes of common and crucian carp. Three distinct Hox sequences, one of them orthologous to a Hox gene in common carp and the other two orthologous to a Hox gene in crucian carp, were isolated in silver crucian carp, indicating a possible hybrid origin of silver crucian carp from crucian and common carp. The gene duplication resulting in the origin of the common ancestor of common and crucian carp likely occurred around 10.9-13.2 Mya. The speciations of common vs. crucian carp and silver crucian vs. crucian carp likely occurred around 8.1-11.4 and 2.3-3.0 Mya, respectively. Finally, nonfunctionalization resulting from point mutations in the coding region is a probable fate for some Hox duplicates. Taken together, these results suggested an evolutionary model for polyploidization in speciation and diversification of polyploid fish.
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Carpes (poisson)/génétique , Protéines de poisson/génétique , Duplication de gène , Protéines à homéodomaine/génétique , Séquence d'acides aminés , Animaux , Évolution moléculaire , Amplification de gène , Données de séquences moléculaires , Phylogenèse , Analyse de séquence d'ADN , Spécificité d'espèceRÉSUMÉ
Hox genes encode transcription factors that play a key role in specifying the body plan in metazoans and are therefore essential in explaining patterns of evolutionary diversity. While each Hox cluster contains the same genes among the different mammalian species, this does not happen in ray-finned fish, in which both the number and organization of Hox genes and even Hox clusters are variables. Here we reveal the organization of Hox genes loci in blunt snout bream. Forty-nine Hox genes including a pseudogene A9b in total have been found in seven clusters as follows: 8 Hox genes in the Aa cluster; 5 in Ab; 10 in Ba; 4 in Bb; 11 in Ca; 4 in Cb; and 7 in Da. In terms of gene content, clusters organization and sequence similarities of putative amino acids, blunt snout bream is more closely related to zebrafish than to fugu and medaka. In contrast to the situation in fugu and medaka, both blunt snout bream and zebrafish have duplicated HoxC cluster but only a single copy of the HoxD cluster. The result implies that the loss of the second HoxD cluster might be a shared feature of the Ostariophysi, to which zebrafish and blunt snout bream both belong. Phylogenetic analysis bases on the paralogous genes from twin clusters supports the duplication-first model, i.e., four original clusters may have duplicated in an event before the divergence of the blunt snout bream-plus-zebrafish lineage and the fugu-plus-medaka lineage. Additionally, the relationship between the decrease of GC level and the loss of conservation and function of one of the paralogous genes from twin clusters is discussed.