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1.
Int Orthop ; 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39122798

RESUMEN

PURPOSE: The step-cut osteotomy has been recognized as a valuable approach for addressing cubitus varus deformity, albeit one that necessitates technical proficiency. This study aims to evaluate the efficacy of the modified step-cut osteotomy technique in conjunction with patient-specific instruments by clinical and radiological assessment. METHODS: We conducted a retrospective review of patients who underwent modified step-cut osteotomy with the use of patient-specific instruments in conjunction with Kirschner wires fixation for the correction of cubitus varus deformity between April 2016 and April 2022. Follow-up was performed for a minimum of two years, during which pre-operative and post-operative clinical and radiological parameters were compared. RESULTS: Fifteen patients were enrolled in this study. The mean pre-operative humeral-elbow-wrist (HEW) of the affected side was -21.7° (ranging from -14° to -34°), while the normal side was 9.4° (ranging from 5° to 15°). The post-operation HEW of affected side was 9° (ranging from 4° to 16°). There was no significant difference between the normal side and affected side after operation (p = 0.74). Pre-operative range of motion in the affected side was 130°, while the post-operative range of motion was 132°. Fourteen patients (93.3%) were pleased with the overall appearance of their elbow. None lazy-S deformity was observed in these cases. There were no major complications. CONCLUSION: The modified step-cut osteotomy technique, utilizing patient-specific instrument in conjunction with Kirschner wires fixation was found to be a safe, reliable, and technically easy procedure for correcting cubitus varus deformity.

2.
Biochemistry ; 62(18): 2710-2716, 2023 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-37647499

RESUMEN

Interactions between two proteins are often mediated by a disordered region in one protein binding to a groove in a folded interaction domain in the other one. While the main determinants of a certain interaction are typically found within a well-defined binding interface involving the groove, recent studies show that nonspecific contacts by flanking regions may increase the affinity. One example is the coupled binding and folding underlying the interaction between the two transcriptional coactivators NCOA3 (ACTR) and CBP, where the flanking regions of an intrinsically disordered region in human NCOA3 increases the affinity for CBP. However, it is not clear whether this flanking region-mediated effect is a peculiarity of this single protein interaction or if it is of functional relevance in a broader context. To further assess the role of flanking regions in the interaction between NCOA3 and CBP, we analyzed the interaction across orthologs and paralogs (NCOA1, 2, and 3) in human, zebra fish, and ghost shark. We found that flanking regions increased the affinity 2- to 9-fold in the six interactions tested. Conservation of the amino acid sequence is a strong indicator of function. Analogously, the observed conservation of increased affinity provided by flanking regions, accompanied by moderate sequence conservation, suggests that flanking regions may be under selection to promote the affinity between NCOA transcriptional coregulators and CBP.


Asunto(s)
Pez Cebra , Animales , Humanos , Secuencia de Aminoácidos , Membrana Celular
3.
BMC Musculoskelet Disord ; 24(1): 77, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36710347

RESUMEN

PURPOSE: To evaluate the outcomes of distal femoral, proximal tibial, and distal tibial physeal bar resection combined with or without the Hemi-Epiphysiodesis procedure and provide a better understanding of the application of physeal bar resection combined with Hemi-Epiphysiodesis procedure in the treatment of physeal bar growth arrest. METHODS: We retrospectively reviewed the patients who suffered physeal bar and underwent physeal bar resection with or without the Hemi-Epiphysiodesis technique during 2010-2020. All were followed up for at least 2 years or to maturity. A modified mapping method was used to determine the area of a physeal bar by CT data. The aLDFA, aMPTA, aLDTA, MAD, and LLD were measured to assess the deformity of the lower limb. RESULTS: In total, 19 patients were included in this study. The average age was 8.9 years (range 4.4 to 13.3 years old). During the follow-up, 4 (21.1%) patients had an angular change < 5°; 12 (63.2%) patients had angular deformity improvement > 5° averaging 10.0° (range 5.3° to 23.2°), and 3 (15.8%) patients had improvement of the angular deformity averaging 16.8° (range 7.4° to 27.1°). Eleven patients (57.9%) had significant MAD improvement. After surgery, we found that 7 (36.8%) patients had an LLD change of < 5 mm and were considered unchanged. Only 2 (15%) patients had an LLD improvement > 5 mm averaging 1.0 cm (range 0.7 to 1.3 cm), and 7 (36.8%) patients had increasing of LLD > 5 mm averaging 1.3 cm (range 0.5 to 2.5 cm). There were no postoperative fractures, infections, or intraoperative complications such as neurovascular injury. CONCLUSION: Physeal bar resection combined with Hemi-epiphysiodesis is helpful for partial epiphysis growth arrest. Without statistically verifying, we still believe that patients with limited growth ability could benefit more from physeal bar resection combined with Hemi-epiphysiodesis.


Asunto(s)
Enfermedades del Desarrollo Óseo , Diferencia de Longitud de las Piernas , Humanos , Preescolar , Niño , Adolescente , Estudios Retrospectivos , Diferencia de Longitud de las Piernas/cirugía , Placa de Crecimiento/diagnóstico por imagen , Placa de Crecimiento/cirugía , Tibia/diagnóstico por imagen , Tibia/cirugía , Fémur/diagnóstico por imagen , Fémur/cirugía
4.
J Bone Miner Metab ; 40(4): 581-593, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35648221

RESUMEN

INTRODUCTION: Osteosarcoma (OS) is the most aggressive malignancy among the bone tumors in the world. Circular RNAs (circRNAs) have been reported to be participated in multiple cancers, including OS. Meanwhile, circPVT1 has been proved to be upregulated in OS. However, the mechanism by which circPVT1 mediates the tumorigenesis of OS remains to be further explored. MATERIALS AND METHODS: Protein and gene expressions in OS cells were measured by western blot and RT-qPCR, respectively. Cell growth was assessed by flow cytometry and colony formation, respectively. In addition, cell migration was assessed by wound healing, and invasion was evaluated by Transwell assay. Meanwhile, the correlation among circPVT1, miR-26b-5p and CCNB1 was explored by RNA pull-down and dual luciferase assay. Finally, in vivo model was established to explore the role of circPVT1 in OS in vivo. RESULTS: CircPVT1 and CCNB1 were significantly upregulated in OS cells, while miR-26b-5p was downregulated. Knockdown of circPVT1 notably inhibited proliferation and induced apoptosis of OS cells. CircPVT1 shRNA significantly suppressed the OS cell invasion and migration. Meanwhile, circPVT1 sponged miR-26b-5p and CCNB1 was found to be the direct target of miR-26b-5p. Furthermore, silencing of circPVT1 inhibited the growth and metastasis of OS in vivo. CONCLUSION: Silencing of circPVT1 notably suppressed the tumorigenesis and metastasis of OS via miR-26b-5p/CCNB1 axis. Therefore, circPVT1 might be used as a target for OS treatment.


Asunto(s)
Neoplasias Óseas , MicroARNs , Osteosarcoma , Neoplasias Óseas/metabolismo , Carcinogénesis/genética , Línea Celular Tumoral , Proliferación Celular/genética , Ciclina B1/genética , Ciclina B1/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Osteosarcoma/genética , Osteosarcoma/patología
5.
Mediators Inflamm ; 2022: 2024974, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36157891

RESUMEN

Hypertrophic cardiomyopathy is a hereditary disease characterized by asymmetric ventricular hypertrophy as the key anatomical feature. Currently, there exists no effective method for the early diagnosis of hypertrophic cardiomyopathy. In this analysis, we incorporated multiple GEO datasets containing RNA profiles of hypertrophic cardiomyopathic patient tissues, identified 642 differentially expressed genes, and performed GO and KEGG analyses. Furthermore, we narrowed down 46 characteristic genes from these differentially expressed genes using random decision forests and conducted transcription factor regulation analysis on them. Using 40 genes that showed overlap between the training set and the verification set, the artificial neural network was trained, and the final MPS scoring model was constructed, and a receiver-operating characteristic (ROC) curve was drawn. We used the MPS model to predict the verification dataset and drew the ROC curve, which demonstrated the good prediction performance of the model. In conclusion, this study combines a random decision forest and artificial neural network to build a diagnostic model for hypertrophic cardiomyopathy to predict the disease, aiming at early detection and treatment, prolonging the survival time, and improving the quality of life of patients.


Asunto(s)
Cardiomiopatía Hipertrófica , Calidad de Vida , Cardiomiopatía Hipertrófica/diagnóstico , Cardiomiopatía Hipertrófica/genética , Humanos , Redes Neurales de la Computación , ARN , Factores de Transcripción
6.
J Biol Chem ; 295(51): 17698-17712, 2020 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-33454008

RESUMEN

Intrinsically disordered protein domains often have multiple binding partners. It is plausible that the strength of pairing with specific partners evolves from an initial low affinity to a higher affinity. However, little is known about the molecular changes in the binding mechanism that would facilitate such a transition. We previously showed that the interaction between two intrinsically disordered domains, NCBD and CID, likely emerged in an ancestral deuterostome organism as a low-affinity interaction that subsequently evolved into a higher-affinity interaction before the radiation of modern vertebrate groups. Here we map native contacts in the transition states of the low-affinity ancestral and high-affinity human NCBD/CID interactions. We show that the coupled binding and folding mechanism is overall similar but with a higher degree of native hydrophobic contact formation in the transition state of the ancestral complex and more heterogeneous transient interactions, including electrostatic pairings, and an increased disorder for the human complex. Adaptation to new binding partners may be facilitated by this ability to exploit multiple alternative transient interactions while retaining the overall binding and folding pathway.


Asunto(s)
Proteínas Intrínsecamente Desordenadas/metabolismo , Secuencia de Aminoácidos , Animales , Proteína de Unión a CREB/química , Proteína de Unión a CREB/genética , Proteína de Unión a CREB/metabolismo , Evolución Molecular , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Proteínas Intrínsecamente Desordenadas/química , Proteínas Intrínsecamente Desordenadas/clasificación , Proteínas Intrínsecamente Desordenadas/genética , Cinética , Simulación de Dinámica Molecular , Mutagénesis Sitio-Dirigida , Coactivador 3 de Receptor Nuclear/química , Coactivador 3 de Receptor Nuclear/genética , Coactivador 3 de Receptor Nuclear/metabolismo , Filogenia , Unión Proteica , Conformación Proteica en Hélice alfa , Dominios Proteicos , Pliegue de Proteína , Estructura Terciaria de Proteína , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Alineación de Secuencia , Electricidad Estática
7.
Int J Clin Pract ; 75(2): e13673, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32791569

RESUMEN

OBJECTIVE: We aimed to evaluate oblique-axis in-plane (OA-IP) techniques for real-time ultrasound-guided internal jugular vein (IJV) cannulation. METHODS: We retrospectively analysed 1065 patients who underwent ultrasound (US)-guided IJV cannulation. We recorded demographic characteristics of patients, success rate, access time, cannulation time, number of attempts and the incidence of acute complications. RESULTS: The overall success rate of the procedure was 100% (n = 1605). In total, 1594 cases (99.3%) were successful at the first attempt, and 11 (0.7%) were successful at the second attempt; no patient required three or more attempts. The mean access time was 18.7 ± 19.3 seconds. The mean cannulation time was 349.0 ± 103.8 seconds. There were 54 (3.4%) acute complications out of the total 1605 cannulations: 23 cases of puncture site bleeding (1.4%), 20 cases allergic to dressing (1.3%), 10 cases of local cervical hematomas (0.6%), and one catheter misplacement (0.1%). There were no major complications 12 hours following the procedure. CONCLUSIONS: The results of our study suggest that OA-IP techniques can improve ultrasound-guided IJV cannulation with a high success rate and safety in clinical practice. Clinicians should consider adopting these methods.


Asunto(s)
Cateterismo Venoso Central , Venas Yugulares , Cateterismo Venoso Central/efectos adversos , Hospitales , Humanos , Venas Yugulares/diagnóstico por imagen , Estudios Prospectivos , Estudios Retrospectivos , Ultrasonografía Intervencional , Universidades
8.
J Cell Mol Med ; 24(19): 11524-11534, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32862562

RESUMEN

Bone fracture is one of the most common injuries. Despite the high regenerative capacity of bones, failure of healing still occurs to near 10% of the patients. Herein, we aim to investigate the modulatory role of neurofibromatosis type I gene (NF1) to osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and new bone formation after fracture in a rat model. We studied the NF1 gene expression in normal and non-union bone fracture models. Then, we evaluated how NF1 overexpression modulated osteogenic differentiation of BMSCs, autophagy activity, mTORC1 signalling and osteoclastic bone resorption by qRT-PCR, Western blot and immunostaining assays. Finally, we injected lentivirus-NF1 (Lv-NF1) to rat non-union bone fracture model and analysed the bone formation process. The NF1 gene expression was significantly down-regulated in non-union bone fracture group, indicating NF1 is critical in bone healing process. In the NF1 overexpressing BMSCs, autophagy activity and osteogenic differentiation were significantly enhanced. Meanwhile, the NF1 overexpression inhibited mTORC1 signalling and osteoclastic bone resorption. In rat non-union bone fracture model, the NF1 overexpression significantly promoted bone formation during fracture healing. In summary, we proved the NF1 gene is critical in non-union bone healing, and NF1 overexpression promoted new bone formation after fracture by enhancing autophagy and inhibiting mTORC1 signalling. Our results may provide a novel therapeutic clue of promoting bone fracture healing.


Asunto(s)
Autofagia/genética , Fracturas Óseas/genética , Fracturas Óseas/patología , Genes de Neurofibromatosis 1 , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Osteogénesis/genética , Transducción de Señal , Animales , Resorción Ósea/genética , Resorción Ósea/patología , Diferenciación Celular/genética , Modelos Animales de Enfermedad , Curación de Fractura/genética , Fracturas no Consolidadas/genética , Fracturas no Consolidadas/patología , Regulación de la Expresión Génica , Células Madre Mesenquimatosas/metabolismo , Osteoclastos/metabolismo , Osteoclastos/patología , Ratas Sprague-Dawley
10.
Mol Cell Biochem ; 429(1-2): 33-43, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28176245

RESUMEN

Understanding the molecular mechanism of gastric cancer cell apoptosis is pivotal for the development of precise therapies targeting this disease. In the present study, we examined the effects of annexin A7 inhibition on the apoptosis of gastric cancer cells and the growth of tumour xenografts in vivo. Expression of annexin A7 in BGC823 cells was suppressed by small interference RNA, and cells apoptosis was assessed by flow cytometry. The mechanism by which annexin A7 mediates apoptosis in BGC823 cells was explored by determining the expression of key apoptosis regulators. In addition, by suppressing annexin A7 in BGC823 cells with small hairpin RNA, we studied the effects of annexin A7 inhibition on in vivo tumour growth. Our results showed that inhibiting annexin A7 expression induced more than fivefold increase in BGC823 cell apoptosis in vitro. This was in concord with a significant decrease of Bcl-2 expression and increases of Bax, Caspase-3, and Caspase-9. The activities of caspase-3 and caspase-9 were increased by 2.95 ± 0.18 and 3.70 ± 0.33 times, respectively, upon the annexin A7 downregulation in BGC823 cells. Importantly, suppressing annexin A7 showed the same apoptotic mechanism in vivo and significantly inhibited the growth of BGC823 xenografts in mice. These data suggest that annexin A7 likely protects gastric cells from apoptosis and targeting it may represent a valuable strategy in future therapeutic development.


Asunto(s)
Anexina A7/genética , Proteínas Reguladoras de la Apoptosis/efectos de los fármacos , ARN Interferente Pequeño/farmacología , Neoplasias Gástricas/genética , Animales , Anexina A7/efectos de los fármacos , Apoptosis , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Trasplante de Neoplasias
11.
Magn Reson Chem ; 55(5): 395-404, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-26662467

RESUMEN

Small isotropic bicelles are versatile membrane mimetics, which, in contrast to micelles, provide a lipid bilayer and are at the same time suitable for solution-state NMR studies. The lipid composition of the bilayer is flexible allowing for incorporation of various head groups and acyl chain types. In bicelles, lipids are solubilized by detergents, which are localized in the rim of the disk-shaped lipid bilayer. Bicelles have been characterized by a broad array of biophysical methods, pulsed-field gradient NMR (PFG NMR) being one of them. PFG NMR can readily be used to measure diffusion coefficients of macromolecules. It is thus employed to characterize bicelle size and morphology. Even more importantly, PFG NMR can be used to study the degree of protein association to membranes. Here, we present the advances that have been made in producing small, fast-tumbling isotropic bicelles from a variety of lipids and detergents, together with insights on the morphology of such mixtures gained from PFG NMR. Furthermore, we review approaches to study protein-membrane interaction by PFG NMR. Copyright © 2015 John Wiley & Sons, Ltd.


Asunto(s)
Membrana Dobles de Lípidos/química , Espectroscopía de Resonancia Magnética/métodos , Difusión , Lípidos de la Membrana/química , Proteínas de la Membrana/química , Micelas , Unión Proteica , Propiedades de Superficie
12.
Heart Surg Forum ; 20(2): E055-E057, 2017 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-28481744

RESUMEN

Congenital right atrial aneurysm is a rare abnormality and may easily be confused with various anomalies, such as pericardial effusion, pericardial cysts, tumors, and Ebstein's anomaly. Patients with right atrial aneurysm may be asymptomatic; but some patients may develop life-threatening complications, such as arrhythmias, congestive heart failure, or pulmonary embolism. Therefore, it is essential for correct diagnosis and appropriate patient management. We report a case of giant right atrial aneurysm in a 7-year-old boy who presented with progressive protrusion of chest. Echocardiography established the definitive diagnosis and surgical resection was successful.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/métodos , Ecocardiografía/métodos , Aneurisma Cardíaco/congénito , Atrios Cardíacos/diagnóstico por imagen , Niño , Aneurisma Cardíaco/diagnóstico , Aneurisma Cardíaco/cirugía , Atrios Cardíacos/cirugía , Humanos , Masculino
13.
Biotechnol Lett ; 38(8): 1331-9, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27206341

RESUMEN

OBJECTIVE: To investigate the xylose operon and properties of xylose isomerase and xylulokinase in Bacillus coagulans that can effectively ferment xylose to lactic acid. RESULTS: The xylose operon is widely present in B. coagulans. It is composed of four putative ORFs. Novel xylA and xylB from B. coagulans NL01 were cloned and expressed in Escherichia coli. Sequence of xylose isomerase was more conserved than that of xylulokinase. Both the enzymes exhibited maximum activities at pH 7-8 but with a high temperature maximum of 80-85 °C, divalent metal ion was prerequisite for their activation. Xylose isomerase and xylulokinase were most effectively activated by Ni(2+) and Co(2+), respectively. CONCLUSIONS: Genomic analysis of xylose operon has contributed to understanding xylose metabolism in B. coagulans and the novel xylose isomerase and xylulokinase might provide new alternatives for metabolic engineering of other strains to improve their fermentation performance on xylose.


Asunto(s)
Isomerasas Aldosa-Cetosa/metabolismo , Bacillus coagulans/enzimología , Operón/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Xilosa/genética , Isomerasas Aldosa-Cetosa/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética
14.
Langmuir ; 30(19): 5488-96, 2014 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-24785902

RESUMEN

Small, fast-tumbling bicelles are frequently used in solution NMR studies of protein-lipid interactions. For this purpose it is critical to have information about the organization of the lipids within the bicelle structure. We have studied the morphology of small, fast-tumbling bicelles containing DMPC and DHPC as a function of temperature, lipid concentration, and the relative ratio (q value) of lipid (DMPC) to detergent (DHPC) amounts. Dynamic light scattering and cryo-transmission electron microscopy techniques were used to measure the size of the bicelles and to monitor the shape and dispersity of the particles in the samples. The stability and size of DMPC-containing bicelle mixtures were found to be highly dependent on temperature and the total lipid concentration for mixtures with q = 1 and q = 1.5. Stable DMPC/DHPC bicelles are only formed at low q values (0.5). Bicelle mixtures with q > 0.5 appear to be multidisperse containing more than one component, one with r(H) around 2.5 nm and one with r(H) of 6-8 nm. This is interpreted as a coexistence of small (possibly mixed micelles) bicelles and much larger bicelles. Incubating the sample at 37 °C increases the phase separation. Moreover, low total amphiphile concentrations and low q values lead to the formation of a temperature-independent morphology, interpreted as the formation of small particles in which the DHPC and DMPC are more mixed. On the basis of these results, we propose the existence of a critical bicelle concentration, a parameter that determines the existence of bilayered bicelles, which varies with q value. This polymorphism was not observed at any concentrations for q = 0.5 bicelles, for which a small but detectable temperature dependence was observed at high concentrations. The results demonstrate that q = 0.5 mixtures predominantly form "classical" bicelles, but that caution is needed when using fast-tumbling mixtures with q values higher than 0.5.


Asunto(s)
Micelas , Dimiristoilfosfatidilcolina/química , Espectroscopía de Resonancia Magnética , Éteres Fosfolípidos/química
15.
Regen Ther ; 26: 42-49, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38818480

RESUMEN

Background: Congenital pseudarthrosis of the tibia (CPT) is a dominant health challenge in pediatric orthopedics. The essential process in the development of CPT is the limited capacity of mesenchymal stem cells (MSCs) derived from CPT to undergo osteogenic differentiation. Our research aimed to elucidate the role and mechanism of methyltransferase-like 3 (METTL3) in the osteogenic differentiation process of CPT MSCs. Methods: The osteogenic differentiation medium was used to culture MSCs, and the detection of osteogenic differentiation was performed using Alizarin Red S and alkaline phosphatase (ALP) assays. Gene or protein expression was assessed by quantitative real-time polymerase chain reaction (qRT-PCR), Western blot, or immunofluorescence (IF) staining. The m6A modification of Homeobox D8 (HOXD8) was verified by methylated RNA immunoprecipitation (MeRIP) assay. Interactions between METTL3 and HOXD8 or HOXD8 and integrin alpha 5 (ITGA5) promoter were validated by the luciferase reporter gene, RIP, and chromatin immunoprecipitation (ChIP) assays. Results: METTL3 overexpression enhanced CPT MSCs' osteogenic differentiation. METTL3 stabilized the HOXD8 in an m6A-dependent manner. Moreover, the overexpressed ITGA5 up-regulated the CPT MSCs' osteogenic differentiation. Further, HOXD8 could transcriptionally activate ITGA5. METTL3 increased the transcription of ITGA5 via HOXD8 to enhance the osteogenic differentiation of CPT MSCs. Conclusion: METTL3 promoted osteogenic differentiation via modulating the HOXD8/ITGA5 axis in CPT MSCs.

16.
J Mol Biol ; 436(6): 168490, 2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38355092

RESUMEN

The emergence of new proteins is a central question in biology. Most tertiary protein folds known to date appear to have an ancient origin, but it is clear from bioinformatic analyses that new proteins continuously emerge in all organismal groups. However, there is a paucity of experimental data on new proteins regarding their structure and biophysical properties. We performed a detailed phylogenetic analysis and identified 48 putative open reading frames in the honeybee-associated bacterium Apilactobacillus kunkeei for which no or few homologs could be identified in closely-related species, suggesting that they could be relatively new on an evolutionary time scale and represent recently evolved proteins. Using circular dichroism-, fluorescence- and nuclear magnetic resonance (NMR) spectroscopy we investigated six of these proteins and show that they are not intrinsically disordered, but populate alpha-helical dominated folded states with relatively low thermodynamic stability (0-3 kcal/mol). The NMR and biophysical data demonstrate that small new proteins readily adopt simple folded conformations suggesting that more complex tertiary structures can be continuously re-invented during evolution by fusion of such simple secondary structure elements. These findings have implications for the general view on protein evolution, where de novo emergence of folded proteins may be a common event.


Asunto(s)
Proteínas Bacterianas , Lactobacillaceae , Pliegue de Proteína , Animales , Dicroismo Circular , Espectroscopía de Resonancia Magnética , Filogenia , Conformación Proteica en Hélice alfa , Termodinámica , Proteínas Bacterianas/química
17.
Biochemistry ; 52(33): 5533-44, 2013 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-23869703

RESUMEN

Certain membrane proteins involved in lipid synthesis can induce formation of new intracellular membranes in Escherichia coli, i.e., intracellular vesicles. Among those, the foreign monotopic glycosyltransferase MGS from Acholeplasma laidlawii triggers such massive lipid synthesis when overexpressed. To examine the mechanism behind the increased lipid synthesis, we investigated the lipid binding properties of MGS in vivo together with the correlation between lipid synthesis and MGS overexpression levels. A good correlation between produced lipid quantities and overexpressed MGS protein was observed when standard LB medium was supplemented with four different lipid precursors that have significant roles in the lipid biosynthesis pathway. Interestingly, this correlation was highest concerning anionic lipid production and at the same time dependent on the selective binding of anionic lipid molecules by MGS. A selective interaction with anionic lipids was also observed in vitro by (31)P NMR binding studies using bicelles prepared with E. coli lipids. The results clearly demonstrate that the discriminative withdrawal of anionic lipids, especially phosphatidylglycerol, from the membrane through MGS binding triggers an in vivo signal for cells to create a "feed-forward" stimulation of lipid synthesis in E. coli. By this mechanism, cells can produce more membrane surface in order to accommodate excessively produced MGS molecules, which results in an interdependent cycle of lipid and MGS protein synthesis.


Asunto(s)
Acholeplasma laidlawii/enzimología , Proteínas Bacterianas/metabolismo , Escherichia coli/metabolismo , Glucosiltransferasas/metabolismo , Lípidos de la Membrana/metabolismo , Fosfolípidos/biosíntesis , Acetatos/metabolismo , Acholeplasma laidlawii/genética , Aniones/química , Aniones/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Unión Competitiva , Electroforesis en Gel de Poliacrilamida , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Glucosiltransferasas/química , Glucosiltransferasas/genética , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Espectroscopía de Resonancia Magnética , Lípidos de la Membrana/química , Modelos Moleculares , Análisis Multivariante , Mutación , Fosfolípidos/química , Unión Proteica , Estructura Terciaria de Proteína , Espectroscopía Infrarroja por Transformada de Fourier , Transformación Genética
18.
Front Pediatr ; 11: 1157192, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37915984

RESUMEN

Background: Physeal bar resection has been used for partial growth arrest treatment for a decade while removing the bony bar minimally invasively and accurately is challenging. This research aims to illustrate a modified arthroscopically assisted surgery, by which all the procedure was under all-inside visualization, without the constant exchange between burring under fluoroscopy, followed by irrigation, suction, and arthroscopy of the canal. Methods: We retrospectively reviewed the patients who sustained physeal bar resection under direct all-inside visualization of the arthroscope during 2016-2021. Patients who underwent physeal bar resection with the aid of an arthroscope for identifying the physeal cartilage but not resecting and visualizing the physeal bar simultaneously were excluded from this study. Results: In total, nine patients with ten related joints were included in this study. All the patients were followed up for at least two years. The average following time was 28.5 ± 6.7 months. Eight patients with nine related joints had an improvement of angular deformity, averaging 8.3 ± 6.9 degrees, and one had a worsening of the angular deformity. All the patients had a leg length discrepancy improvement, while four patients still had LLD >1 cm. The surgery time was 3.1 ± 0.7 h. There were no postoperative fractures, infections, or intraoperative complications such as neurovascular injury. Conclusions: Using clamps to form a closed osteocavity could make physeal bar resection under all-inside arthroscopic visualization feasible, which is minimally invasive, accurate, and safe.

19.
Elife ; 122023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36920032

RESUMEN

Increasing numbers of small proteins with diverse physiological roles are being identified and characterized in both prokaryotic and eukaryotic systems, but the origins and evolution of these proteins remain unclear. Recent genomic sequence analyses in several organisms suggest that new functions encoded by small open reading frames (sORFs) may emerge de novo from noncoding sequences. However, experimental data demonstrating if and how randomly generated sORFs can confer beneficial effects to cells are limited. Here, we show that by upregulating hisB expression, de novo small proteins (≤50 amino acids in length) selected from random sequence libraries can rescue Escherichia coli cells that lack the conditionally essential SerB enzyme. The recovered small proteins are hydrophobic and confer their rescue effect by binding to the 5' end regulatory region of the his operon mRNA, suggesting that protein binding promotes structural rearrangements of the RNA that allow increased hisB expression. This study adds RNA regulatory elements as another interacting partner for de novo proteins isolated from random sequence libraries and provides further experimental evidence that small proteins with selective benefits can originate from the expression of nonfunctional sequences.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas/metabolismo , ARN/metabolismo , Operón , Sistemas de Lectura Abierta/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo
20.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 37(9): 901-5, 2012 Sep.
Artículo en Zh | MEDLINE | ID: mdl-23000763

RESUMEN

OBJECTIVE: To compare the blood flow in sequential and individual saphenous vein grafts (SVGs) and to analyze the influence of the location of the target vessel in off-pump coronary artery bypass grafting (OPCAB). METHODS: A total of 464 SVGs in 412 patients receiving OPCAB were nested into individual SVG (n=206), double (n=241) or triple sequential SVG (n=15), and analyzed. RESULTS: The blood flow in double and triple SVGs was significantly higher than in individual SVGs [(43.4±22.5), (43.7±19.2) and (28.9±18.7) mL/min, respectively, P<0.001, P=0.047]. There were no differences between flow in double and triple SVGs (P=0.96). Pulsatility index (PI) of the three groups were similar (2.6±1.2, 2.5±1.6, 2.8±0.9, respectively, P=0.49, P=0.49). In individual SVGs to right coronary artery, the blood flow was higher than in the posterior descending branch (PDA) (P=0.047) and posterior branch of left ventricle (PBLV), the flow-time in systole period was longer than diagonals (P=0.003), obtuse marginal (OM) (P=0.013) and PDA (P=0.002), PI was significantly lower than PDA (P=0.033) and PBLV (P=0.032). The blood flow in individual SVGs to diagonals was significantly lower than in other target vessels except for PBLV (P<0.05). Flow in double SVGs to PDA-PBLV was significantly lower than in PDA-OM. CONCLUSION: The mean blood flow in double and triple sequential SVGs is about 1.5 times higher than in individual SVGs. Individual, double, and triple SVGs have similar pI. Flow in individual SVGs to diagonals was significantly lower than in other target vessels except for PBLV.


Asunto(s)
Puente de Arteria Coronaria Off-Pump/métodos , Supervivencia de Injerto , Vena Safena/trasplante , Adulto , Anciano , Angina Inestable/cirugía , Velocidad del Flujo Sanguíneo , Circulación Coronaria , Enfermedad Coronaria/cirugía , Femenino , Humanos , Masculino , Arterias Mamarias/trasplante , Persona de Mediana Edad , Vena Safena/fisiopatología
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