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1.
Polymers (Basel) ; 16(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38794537

RESUMO

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.

2.
Front Neurosci ; 18: 1377702, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38629052

RESUMO

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.

3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(5): 953-964, 2023 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-37879925

RESUMO

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.


Assuntos
Exoesqueleto Energizado , Reabilitação do Acidente Vascular Cerebral , Humanos , Reprodutibilidade dos Testes , Caminhada/fisiologia , Extremidade Inferior , Algoritmos , Reabilitação do Acidente Vascular Cerebral/métodos
4.
BMJ Open ; 13(6): e071092, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37316317

RESUMO

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.


Assuntos
Fibromialgia , Oxigenoterapia Hiperbárica , Humanos , Fibromialgia/terapia , Qualidade de Vida , Dor , Fadiga , Revisões Sistemáticas como Assunto , Metanálise como Assunto
5.
Front Nutr ; 9: 927363, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36118755

RESUMO

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.

6.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(1): 207-216, 2022 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-35231983

RESUMO

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.


Assuntos
Nanoestruturas , Infecção dos Ferimentos , Antibacterianos/farmacologia , Humanos , Nanoestruturas/uso terapêutico , Staphylococcus aureus , Cicatrização , Infecção dos Ferimentos/terapia
8.
Exp Cell Res ; 404(2): 112636, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34019907

RESUMO

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.


Assuntos
Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Melanoma/genética , Melanoma/patologia , Proteínas dos Microfilamentos/genética , Animais , Apoptose/genética , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Melanoma/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
9.
ACS Chem Neurosci ; 11(20): 3259-3266, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-32946211

RESUMO

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.


Assuntos
MicroRNAs , Doenças Neurodegenerativas , Doença de Parkinson , Animais , Apoptose , Cinamatos , Depsídeos , Inflamação/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Estresse Oxidativo , Ácido Rosmarínico
10.
Neural Regen Res ; 14(2): 354-360, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30531020

RESUMO

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.

11.
Biomed Res Int ; 2018: 3450940, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29581969

RESUMO

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.


Assuntos
Bursite , Tratamento por Ondas de Choque Extracorpóreas , Manejo da Dor , Medição da Dor , Bursite/patologia , Bursite/fisiopatologia , Bursite/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/patologia , Dor/fisiopatologia , Estudos Retrospectivos
12.
J Biomed Mater Res A ; 103(12): 3886-95, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26123537

RESUMO

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.


Assuntos
Cartilagem Articular/citologia , Condrogênese , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Ácido Láctico/química , Células-Tronco Mesenquimais/citologia , Ácido Poliglicólico/química , Fatores de Transcrição SOX9/genética , Alicerces Teciduais/química , Tecido Adiposo/citologia , Animais , Fenômenos Biomecânicos , Cartilagem Articular/fisiologia , Células Cultivadas , Células-Tronco Mesenquimais/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Engenharia Tecidual/métodos , Regulação para Cima
13.
J Appl Physiol (1985) ; 113(4): 619-26, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22723630

RESUMO

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.


Assuntos
Matriz Óssea/metabolismo , Proliferação de Células , Células Endoteliais/metabolismo , Mecanotransdução Celular , Neovascularização Fisiológica , Células-Tronco/metabolismo , Engenharia Tecidual , Alicerces Teciduais , Animais , Reatores Biológicos , Técnica de Desmineralização Óssea , Células Cultivadas , Células Endoteliais/transplante , Células Endoteliais/ultraestrutura , Regulação da Expressão Gênica , Microscopia Eletrônica de Varredura , Neovascularização Fisiológica/genética , Pressão , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Transplante de Células-Tronco , Células-Tronco/ultraestrutura , Suínos , Fatores de Tempo , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo
14.
Chin J Traumatol ; 14(4): 241-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21801670

RESUMO

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.


Assuntos
Placas Ósseas , Fíbula , Fêmur , Fixação Interna de Fraturas , Fraturas Ósseas , Humanos
15.
Gene ; 470(1-2): 46-52, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20951190

RESUMO

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.


Assuntos
Carpas/genética , Proteínas de Peixes/genética , Fator de Crescimento Insulin-Like II/genética , Sequência de Aminoácidos , Animais , Carpas/metabolismo , Evolução Molecular , Genes Duplicados , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência
16.
J Exp Zool B Mol Dev Evol ; 314(6): 445-56, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20700889

RESUMO

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.


Assuntos
Carpas/genética , Proteínas de Peixes/genética , Duplicação Gênica , Proteínas de Homeodomínio/genética , Sequência de Aminoácidos , Animais , Evolução Molecular , Amplificação de Genes , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie
17.
Gene ; 400(1-2): 60-70, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17618068

RESUMO

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.


Assuntos
Cyprinidae/genética , Animais , Sequência de Bases , Evolução Molecular , Duplicação Gênica , Genes Homeobox , Dados de Sequência Molecular , Família Multigênica , Oryzias , Filogenia , Homologia de Sequência do Ácido Nucleico , Takifugu , Peixe-Zebra
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