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1.
World J Gastrointest Surg ; 16(6): 1618-1628, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38983338

RESUMEN

BACKGROUND: Patients with resectable gastric adenocarcinoma accompanied by vascular cancer thrombus (RGAVCT) have a poor prognosis, with a 5-year survival rate ranging from 18.42%-53.57%. These patients need a reasonable postoperative treatment plan to improve their prognosis. AIM: To determine the most effective postoperative chemotherapy regimen for patients with RGAVCT. METHODS: We retrospectively collected the clinicopathological data of 530 patients who underwent radical resection for gastric cancer between January 2017 and January 2022 and who were pathologically diagnosed with gastric adenocarcinoma with a choroidal cancer embolus. Furthermore, we identified the high-risk variables that can influence the prognosis of patients with RGAVCT by assessing the clinical and pathological features of the patients who met the inclusion criteria. We also assessed the significance of survival outcomes using Mantel-Cox univariate and multivariate analyses. The subgroups of patients with stages I, II, and III disease who received single-, dual-, or triple-drug regimens following surgery were analyzed using SPSS 25.0 and the ggplot2 package in R 4.3.0. RESULTS: In all, 530 eligible individuals with RGAVCT were enrolled in this study. The median overall survival (OS) of patients with RGAVCT was 24 months, and the survival rates were 80.2%, 62.5%, and 42.3% at 12, 24, and 59 months, respectively. Preoperative complications, tumor size, T stage, and postoperative chemotherapy were identified as independent factors that influenced OS in patients with RGAVCT according to the Cox multivariate analysis model. A Kaplan-Meier analysis revealed that chemotherapy had no effect on OS of patients with stage I or II RGAVCT; however, chemotherapy did have an effect on OS of stage III patients. Stage III patients who were treated with chemotherapy consisting of dual- or triple-agent regimens had better survival than those treated with single-agent regimens, and no significant difference was observed in the survival of patients treated with chemotherapy consisting of dual- or triple-agent regimens. CONCLUSION: For patients with stage III RGAVCT, a dual-agent regimen of postoperative chemotherapy should be recommended rather than a triple-agent treatment, as the latter is associated with increased frequency of adverse events.

2.
Adv Sci (Weinh) ; 11(23): e2401301, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38544484

RESUMEN

The left atrial appendage (LAA) occluder is an important medical device for closing the LAA and preventing stroke. The device-related thrombus (DRT) prevents the implantation of the occluder in exerting the desired therapeutic effect, which is primarily caused by the delayed endothelialization of the occluder. Functional coatings are an effective strategy for accelerating the endothelialization of occluders. However, the occluder surface area is particularly large and structurally complex, and the device is subjected to a large shear friction in the sheath during implantation, which poses a significant challenge to the coating. Herein, a hydrogel coating by the in situ UV-triggered polymerization of double-network polyelectrolytes is reported. The findings reveal that the double network and electrostatic interactions between the networks resulted in excellent mechanical properties of the hydrogel coating. The sulfonate and Arg-Gly-Asp (RGD) groups in the coating promoted hemocompatibility and endothelial growth of the occluder, respectively. The coating significantly accelerated the endothelialization of the LAA occluder in a canine model is further demonstrated. This study has potential clinical benefits in reducing both the incidence of DRT and the postoperative anticoagulant course for LAA closure.


Asunto(s)
Hidrogeles , Polielectrolitos , Animales , Hidrogeles/química , Polielectrolitos/química , Perros , Apéndice Atrial/cirugía , Rayos Ultravioleta , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología
3.
Int Wound J ; 21(2): e14594, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38379217

RESUMEN

To evaluate the efficacy of cognitive behavioural therapy (CBT) as a psychological intervention for elderly patients with extensive burns, focusing on its impact on emotional well-being, self-efficacy and quality of life. A prospective, randomized study involving 200 elderly burn patients was conducted from November 2021 to January 2023. The patients were randomly assigned to receive either standard care (control group) or burn care based on cognitive behavioural therapy (CBT-B) (study group), with 100 patients in each group. Outcome measures included the Visual Analog Scale (VAS) for pain assessment, 36-item Short Form Survey (SF-36) for quality of life, General Self-Efficacy Scale (GSES) and Rosenberg Self-Esteem Scale (RSES). The study revealed that CBT-based intervention significantly reduced anxiety and depression scores compared with standard care (p < 0.05). Additionally, patients in the CBT group exhibited improved self-efficacy, self-esteem and quality of life (p < 0.05). CBT proves to be a valuable intervention for elderly burn patients, effectively addressing emotional distress and enhancing their psychological well-being. By modifying negative cognitive patterns, providing coping mechanisms and fostering problem-solving skills, CBT-based care contributes to a more positive recovery experience and improved quality of life.


Asunto(s)
Terapia Cognitivo-Conductual , Calidad de Vida , Humanos , Anciano , Estudios Prospectivos , Intervención Psicosocial , Ansiedad/terapia
5.
Soft Matter ; 19(17): 3162-3166, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37057642

RESUMEN

A fullerene-polysaccharide supramolecular hydrogel was constructed by carrying out a co-assembly of fullerene@hydroxypropyl-ß-cyclodextrin, chitosan and bentonite, and displayed good antioxidant and antiglycation properties, and hence showed promising cosmetics applications. Benefitting from the cyclodextrin hydrophobic cavity, hydroxypropyl-ß-cyclodextrin formed a stoichiometric 2 : 1 complex with fullerene, effectively enhancing the water solubility and biological activity of fullerene, and the encapsulation ratio of the prepared fullerene was calculated to be 79%. Results of oxygen radical absorbance capacity and pyrogallol autoxidation experiments showed high antioxidant activity displayed by the fullerene@HP-ß-CD inclusion complex. The supramolecular inclusion was further co-assembled, using multiple hydrogen bonds and electrostatic interactions, with chitosan and bentonite to form a supramolecular hydrogel; this hydrogel was successfully used in antiglycation, with a glycation end products inhibition rate of 43.99% at a 10% sample concentration. Therefore, the fullerene-polysaccharide ternary co-assembly supramolecular hydrogel showed good antioxidant and antiglycation abilities, and the construction of the polysaccharide supramolecular hydrogel provided a new perspective for raw materials to consider in cosmetics applications.

6.
Sci Rep ; 11(1): 17558, 2021 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-34475445

RESUMEN

Individuals with mild cognitive impairment (MCI) are clinically heterogeneous, with different risks of progression to Alzheimer's disease. Regular follow-up and examination may be time-consuming and costly, especially for MRI and PET. Therefore, it is necessary to identify a more precise MRI population. In this study, a two-stage screening frame was proposed for evaluating the predictive utility of additional MRI measurements among high-risk MCI subjects. In the first stage, the K-means cluster was performed for trajectory-template based on two clinical assessments. In the second stage, high-risk individuals were filtered out and imputed into prognosis models with varying strategies. As a result, the ADAS-13 was more sensitive for filtering out high-risk individuals among patients with MCI. The optimal model included a change rate of clinical assessments and three neuroimaging measurements and was significantly associated with a net reclassification improvement (NRI) of 0.246 (95% CI 0.021, 0.848) and integrated discrimination improvement (IDI) of 0.090 (95% CI - 0.062, 0.170). The ADAS-13 longitudinal models had the best discrimination performance (Optimism-corrected concordance index = 0.830), as validated by the bootstrap method. Considering the limited medical and financial resources, our findings recommend follow-up MRI examination 1 year after identification for high-risk individuals, while regular clinical assessments for low-risk individuals.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Disfunción Cognitiva/diagnóstico , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Pruebas Neuropsicológicas/normas , Tomografía de Emisión de Positrones/métodos , Anciano , Enfermedad de Alzheimer/psicología , Disfunción Cognitiva/psicología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Pronóstico , Curva ROC , Factores de Riesgo , Tasa de Supervivencia
7.
Clin Exp Med ; 21(3): 429-437, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33779886

RESUMEN

Imbalanced Th17/Treg ratio is implicated in the pathogenesis of aplastic anemia. Studies have indicated that bone marrow-derived mesenchymal stem cells-derived exosomes (BMSC-Exo) could correct imbalanced Th17/Treg in aplastic anemia, but the mechanism remains not fully understand. This study was designed to investigate whether BMSC-Exo regulates the Th17/Treg balance in aplastic anemia by transferring miR-23a-3p. Here, miR-23a-3p inhibitor was utilized to knockdown the expression of miR-23a-3p in BMSC-Exo. A co-culture system of CD4+ T cells from aplastic anemia patients and BMSC-Exo was used to explore the effects of BMSC-Exo on the Th17/Treg balance and the underlying mechanism in aplastic anemia. The patients with aplastic anemia exhibited Th17/Treg imbalance favoring the Th17 cells. BMSC-Exo could balance the percentage of Th17 and Treg cells in aplastic anemia, but the effects of BMSC-Exo can be eliminated when miR-23a-3p expression was silenced in BMSCs. IL-6 was a direct target of miR-23a-3p. IL-6 overexpression could abrogate BMSC-Exo-induced balance in Th17/Treg ratio. Overall, BMSC-Exo could balance Th17/Treg ratio in aplastic anemia via suppressing IL-6 expression by transferring miR-23a-3p at least in part. These data indicated miR-23a-3p may be a potential target for the treatment of aplastic anemia. Our study may provide a new idea for the therapy of the disease.


Asunto(s)
Anemia Aplásica/genética , Linfocitos T CD4-Positivos/citología , Interleucina-6/genética , Células Madre Mesenquimatosas/citología , MicroARNs/genética , Regiones no Traducidas 3' , Anemia Aplásica/inmunología , Linfocitos T CD4-Positivos/inmunología , Estudios de Casos y Controles , Células Cultivadas , Técnicas de Cocultivo , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Interleucina-6/metabolismo , Células Madre Mesenquimatosas/metabolismo , Linfocitos T Reguladores , Células Th17
8.
Sci Rep ; 10(1): 20186, 2020 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-33214634

RESUMEN

Obstructive sleep apnea syndrome (OSAS) can lead to alterations in right ventricular (RV) performance and pulmonary vascular haemodynamics. Additionally, altitude-related hypoxia is associated with pulmonary vasoconstriction, and the effect of high-altitude on the pulmonary circulation in OSAS patients can be further altered. We sought to assess alterations in RV morphology and function in OSAS patients living at high altitude by way of 2-dimensional speckle tracking echocardiography (2D-STE), real-time 3- dimensional echocardiography (RT-3DE) and cardiac biomarkers. We also evaluate the impact of continuous positive airway pressure (CPAP) treatment on RV performance. Seventy-one patients with newly diagnosed OSAS and thirty-one controls were included in this study. All individuals were assessed for cardiac biomarkers as well as underwent 2D-STE and RT-3DE. Forty-five OSAS patients underwent CPAP therapy for at least 24 weeks and were studied before and after CPAP treatment. RT-3DE was used to measure RV volume, and calculate RV 3D ejection fraction (3D RVEF). Peak systolic strain was determined. Cardiac biomarkers, including C-reactive protein (CRP), N-terminal pro-B-type natriuretic peptide, and cardiac troponin T were also measured. Right atrium volume index, RV volume, RV volume index, systolic pulmonary artery pressure (sPAP), pulmonary vascular resistance (PVR) and level of serum CRP were significantly higher in OSAS group, while OSAS patients showed lower 3D RVEF and RV longitudinal strains. Compared to the patients with sPAP < 40 mmHg, RV longitudinal strains in patients with sPAP ≥ 40 mmHg were lower. Both RV global longitudinal strain and sPAP were associated with apnea-hypopnea index. Patients treated with 6 months of CPAP therapy had significant improvement in RV geometry and performance. RV structural abnormalities and RV function impairments were observed in OSAS patients living at moderate high altitude compared to control highlanders. The reversibility of these changes after application of CPAP were further confirmed.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua , Ventrículos Cardíacos/fisiopatología , Apnea Obstructiva del Sueño/terapia , Función Ventricular Derecha/fisiología , Adulto , Altitud , Ecocardiografía Tridimensional , Femenino , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana Edad , Polisomnografía , Apnea Obstructiva del Sueño/fisiopatología
9.
Int J Mol Med ; 46(1): 415-426, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32626908

RESUMEN

The present study aimed to establish a cellular model to test the hypothesis that oncogene-induced senescence (OIS) is triggered by aging-related activation of microglia. Primary microglia were incubated with phorbol 12-myristate 13-acetate (PMA), and ß-galactosidase (ß-Gal) staining was applied to subsequent assessment of cellular senescence. Moreover, flow cytometry was employed for examinations of cell cycle arrest and senescence-associated proteins, p53 and p21 were measured by western blotting. Furthermore, examination of tumor necrosis factor α (TNF-α) and interleukin-1ß (IL-1ß) were carried out with microglia supernatants undergoing age-related degenerative diseases in the nervous system, using ELISA. PC12 cells were co-cultured with microglia activated by aging-related alteration(s) to evaluate whether apoptosis was increased in PC12 cells. Cellular senescence-associated ß-Gal staining showed that microglial ß-Gal expression gradually increased with prolonged PMA stimulation. Microglia in the group receiving 72 h of PMA stimulation displayed the highest percentage of cells arrested in G0/G1, the highest amount of senescence-associated expression of p53 and p21, and the most prominent secretion of TNF-α and IL-1ß. In comparison with controls, an increase of apoptotic PC12 cells was detected, which were co-cultured with aging microglia. Taken together, microglia tend to undergo senescence after PMA treatment, suggesting that microglial senescence is associated with inactivation of certain oncogenes.


Asunto(s)
Microglía/patología , Acetato de Tetradecanoilforbol/farmacología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Puntos de Control del Ciclo Celular/efectos de los fármacos , Senescencia Celular/efectos de los fármacos , Senescencia Celular/genética , Ensayo de Inmunoadsorción Enzimática , Interleucina-1beta/metabolismo , Microglía/metabolismo , Células PC12 , Ratas , Factor de Necrosis Tumoral alfa/metabolismo
10.
Huan Jing Ke Xue ; 41(7): 3194-3203, 2020 Jul 08.
Artículo en Chino | MEDLINE | ID: mdl-32608892

RESUMEN

Based on the survey data of eight kinds of heavy metals in the Xiangshan Bay watershed during the flood season, the pollution status of heavy metals in water was analyzed. The potential ecological risks of heavy metals were evaluated based on the single factor pollution index (Pi), the Nemero comprehensive pollution index (Pn), and the heavy metal pollution index (HPI). Based on the correlation between land-use types and heavy metal concentrations, the sources of heavy metals were analyzed. The results show that the average concentration of heavy metals is in the order Fe > Mn > Zn > Cu > As > Cr > Pb > Cd. All heavy metal concentrations, except those of Mn and Fe, conform to the class I surface water environment quality standard. The risk level of heavy metals is low, and there is no pollution, but some contamination. Agricultural non-point source pollution is the main factor in the contamination of heavy metals. Overall, the heavy metals in the region have not reached the risk threshold. To reasonably avoid the risk of heavy metal pollution in the urban development process, it is important to strengthen the supervision of pollution sources based on agricultural non-point sources.

11.
Neuromodulation ; 23(4): 444-450, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31830772

RESUMEN

OBJECTIVES: Deep brain stimulation (DBS) for Parkinson's disease (PD) has been applied to clinic for approximately 30 years. The goal of this review is to explore the similarities and differences between "awake" and "asleep" DBS techniques. METHODS: A comprehensive literature review was carried out to identify relevant studies and review articles describing applications of "awake" or "asleep" DBS for Parkinson's disease. The surgical procedures, clinical outcomes, costs and complications of each technique were compared in detail through literature review. RESULTS: The surgical procedures of awake and asleep DBS surgeries rely upon different methods for verification of intended target acquisition. The existing research results demonstrated that the stereotactic targeting accuracy of lead placement obtained by either method is reliable. There were no significant differences in clinical outcomes, costs, or complications between the two techniques. CONCLUSION: The surgical and clinical outcomes of asleep DBS for PD are comparable to those of awake DBS.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Enfermedad de Parkinson/terapia , Resultado del Tratamiento , Anestesia General , Anestesia Local , Humanos , Inconsciencia , Vigilia
12.
Cell Prolif ; 52(1): e12526, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30407674

RESUMEN

OBJECTIVES: LncRNA nuclear-enriched abundant transcript 1 (NEAT1) participates in the development and progression of multiple malignancies. However, the molecular mechanism by which NEAT1 contributes to colorectal cancer (CRC) remains unclear. METHODS: The association between lncRNA NEAT1 expression and clinicopathological characteristics and prognosis in patients with CRC was analysed by TCGA RNA-sequencing data. MTT, colony formation, flow cytometry, transwell assays and a xenograft tumour model were used to assess the functions of NEAT1. Bioinformatics and spearman correlation analysis were used to identify the NEAT1-specific binding with miRNAs, and luciferase gene report and RIP assays were performed to confirm the interaction between miR-193a-3p (miR-193a) and NEAT1 in CRC cells. RESULTS: Upregulation of NEAT1 expression was significantly correlated with TNM stage, poor survival and tumour recurrence in patients with CRC, and acted as an independent prognostic factor for tumour recurrence. Knockdown of NEAT1 suppressed cell proliferation, colony formation abilities and invasive potential and induced cell apoptosis, but overexpression of NEAT1 reversed these effects. Furthermore, NEAT1 was confirmed to act as a sponge of miR-193a, and knockdown of NEAT1 attenuated miR-193a inhibitor-induced tumour promoting effects and L17RD expression in CRC cells. miR-193a harboured negative correlation with NEAT1 and IL17RD expression in CRC specimens. In vivo experiment further validated the inhibitory effects of NEAT1 knockdown on xenograft tumour growth. CONCLUSION: Our findings demonstrate that lncRNA NEAT1 acts as an oncogenic role in CRC cells by sponging miR-193a and may represent a potential marker for CRC patients.


Asunto(s)
Carcinogénesis/genética , Neoplasias Colorrectales/genética , MicroARNs/genética , ARN Largo no Codificante/genética , Anciano , Animales , Apoptosis/genética , Células CACO-2 , Cadherinas/biosíntesis , Línea Celular Tumoral , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica/genética , Regulación hacia Arriba , Vimentina/biosíntesis , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Gene ; 627: 169-175, 2017 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-28629826

RESUMEN

Neuropathic pain is chronic pain caused by lesions or diseases of the somatosensory system, currently available analgesics provide only temporal relief. The precise role of FK506 binding protein 51 (FKBP51) in neuropathic pain induced by chronic constriction injury (CCI) is not clear. The purpose of the present study was to investigate the effects and possible mechanisms of FKBP51 in neuropathic pain in the rat model of CCI. Our results showed that FKBP51 was obviously upregulated in a time-dependent manner in the dorsal root ganglion (DRG) of CCI rats. Additionally, silencing of FKBP51 remarkably attenuated mechanical allodynia and thermal hyperalgesia as reflected by paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) in CCI rats. Moreover, knockdown of FKBP51 reduced the production of pro-inflammatory cytokines (TNF-α, IL-1ß and IL-6), nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) expression in the DRG of CCI rats. Furthermore, we revealed that inhibition of FKBP51 greatly suppressed the activation of the NF-kappaB (NF-κB) signaling in the DRG of CCI rats. Interestingly, similar to the FKBP51 siRNA (si-FKBP51), ammonium pyrrolidinedithiocarbamate (PDTC, an inhibitor of NF-κB) also alleviated neuropathic pain and neuro-inflammation, indicating that knockdown of FKBP51 alleviated neuropathic pain development of CCI rats by inhibiting the activation of NF-κB signaling pathway. Taken together, our findings indicate that FKBP51 may serve as a novel therapeutic target for neuropathic pain.


Asunto(s)
Citocinas/metabolismo , Ganglios Espinales/metabolismo , Silenciador del Gen , FN-kappa B/metabolismo , Neuralgia/genética , Umbral del Dolor , Proteínas de Unión a Tacrolimus/genética , Animales , Citocinas/genética , Ganglios Espinales/citología , Masculino , Neuralgia/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Proteínas de Unión a Tacrolimus/metabolismo , Tacto
14.
World J Surg Oncol ; 14: 96, 2016 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-27036540

RESUMEN

BACKGROUND: Laparoscopic-assisted total gastrectomy (LATG) is the most commonly used methods of laparoscopic gastrectomy for upper and middle gastric cancer. However, totally laparoscopic total gastrectomy (TLTG) is unpopular because reconstruction is difficult, especially for the intracorporeal esophagojejunostomy. We adopted TLTG with various types of intracorporeal esophagojejunostomy. In this study, we compared LATG and TLTG to evaluate their outcomes. METHODS: From March 2006 to September 2015, 253 patients with upper and middle gastric cancer underwent laparoscopic total gastrectomy (LTG), 145 patients underwent LATG, and 108 patients underwent TLTG. The clinicopathological characteristics and postoperative outcomes were retrospectively compared between the two groups. Furthermore, a systematic review and meta-analysis were conducted. RESULTS: The operation time and estimated blood loss were similar between the groups. There were no significant differences in first flatus, diet initiation, and postoperative hospital stay. The surgical complication rates were 17.2% (25/145) and 13.9% (15/108) in the LATG and TLTG groups, respectively. The meta-analysis also revealed no significant differences in the operation time, estimated blood loss, time to first flatus, length of hospital stay, overall, and anastomosis-related complications among the groups. CONCLUSIONS: TLTG is a feasible choice for gastric cancer patients, with comparable results to the LATG approach.


Asunto(s)
Gastrectomía/métodos , Laparoscopía/métodos , Neoplasias Gástricas/cirugía , Femenino , Estudios de Seguimiento , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Neoplasias Gástricas/patología , Tasa de Supervivencia
15.
Nucleic Acids Res ; 44(8): 3936-45, 2016 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-26939889

RESUMEN

Despite over 3300 protein-DNA complex structures have been reported in the past decades, there remain some unknown recognition patterns between protein and target DNA. The silkgland-specific transcription factor FMBP-1 from the silkworm Bombyx mori contains a unique DNA-binding domain of four tandem STPRs, namely the score and three amino acid peptide repeats. Here we report three structures of this STPR domain (termed BmSTPR) in complex with DNA of various lengths. In the presence of target DNA, BmSTPR adopts a zig-zag structure of three or four tandem α-helices that run along the major groove of DNA. Structural analyses combined with binding assays indicate BmSTPR prefers the AT-rich sequences, with each α-helix covering a DNA sequence of 4 bp. The successive AT-rich DNAs adopt a wider major groove, which is in complementary in shape and size to the tandem α-helices of BmSTPR. Substitutions of DNA sequences and affinity comparison further prove that BmSTPR recognizes the major groove mainly via shape readout. Multiple-sequence alignment suggests this unique DNA-binding pattern should be highly conserved for the STPR domain containing proteins which are widespread in animals. Together, our findings provide structural insights into the specific interactions between a novel DNA-binding protein and a unique deformed B-DNA.


Asunto(s)
Proteínas de Unión al ADN/química , ADN/química , Proteínas de Insectos/química , Factores de Transcripción/química , Animales , Sitios de Unión , Bombyx , ADN/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Insectos/metabolismo , Modelos Moleculares , Conformación de Ácido Nucleico , Unión Proteica , Conformación Proteica en Hélice alfa , Dominios Proteicos , Secuencias Repetitivas de Ácidos Nucleicos , Factores de Transcripción/metabolismo
17.
Sci Rep ; 5: 16470, 2015 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-26576507

RESUMEN

The one-dimensional pattern of heterocyst in the model cyanobacterium Anabaena sp. PCC 7120 is coordinated by the transcription factor HetR and PatS peptide. Here we report the complex structures of HetR binding to DNA, and its hood domain (HetRHood) binding to a PatS-derived hexapeptide (PatS6) at 2.80 and 2.10 Å, respectively. The intertwined HetR dimer possesses a couple of novel HTH motifs, each of which consists of two canonical α-helices in the DNA-binding domain and an auxiliary α-helix from the flap domain of the neighboring subunit. Two PatS6 peptides bind to the lateral clefts of HetRHood, and trigger significant conformational changes of the flap domain, resulting in dissociation of the auxiliary α-helix and eventually release of HetR from the DNA major grove. These findings provide the structural insights into a prokaryotic example of Turing model.


Asunto(s)
Proteínas Bacterianas/química , Anabaena/genética , Anabaena/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Sitios de Unión , Modelos Moleculares , Conformación de Ácido Nucleico , Motivos de Nucleótidos , Regiones Promotoras Genéticas , Unión Proteica , Conformación Proteica , Relación Estructura-Actividad
18.
PLoS One ; 10(10): e0140953, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26479246

RESUMEN

Peptidoglycan recognition proteins (PGRPs), which have been identified in most animals, are pattern recognition molecules that involve antimicrobial defense. Resulting from extraordinary expansion of innate immune genes, the amphioxus encodes many PGRPs of diverse functions. For instance, three isoforms of PGRP encoded by Branchiostoma belcheri tsingtauense, termed BbtPGRP1~3, are fused with a chitin binding domain (CBD) at the N-terminus. Here we report the 2.7 Å crystal structure of BbtPGRP3, revealing an overall structure of an N-terminal hevein-like CBD followed by a catalytic PGRP domain. Activity assays combined with site-directed mutagenesis indicated that the individual PGRP domain exhibits amidase activity towards both DAP-type and Lys-type peptidoglycans (PGNs), the former of which is favored. The N-terminal CBD not only has the chitin-binding activity, but also enables BbtPGRP3 to gain a five-fold increase of amidase activity towards the Lys-type PGNs, leading to a significantly broadened substrate spectrum. Together, we propose that modular evolution via domain shuffling combined with gene horizontal transfer makes BbtPGRP1~3 novel PGRPs of augmented catalytic activity and broad recognition spectrum.


Asunto(s)
Proteínas Portadoras/química , Proteínas Portadoras/metabolismo , Quitina/metabolismo , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Secuencia de Aminoácidos , Animales , Proteínas Portadoras/genética , Evolución Molecular , Anfioxos , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Terciaria de Proteína , Proteínas Recombinantes de Fusión/genética
19.
Mol Med Rep ; 12(5): 7271-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26459397

RESUMEN

Phorbol myristate acetate (PMA), as a potent tumor promoter, may induce microglial senescence. The present study investigated the effect of PMA infection on microglial senescence. From 58 male Sprague­Dawley rats, 10 were randomly selected and divided into a PMA injection group, containing five rats (0.5 µg/µl PMA) and a control group, containing five rats (commensurable 0.9% saline). Immunofluorescent staining of Iba­1 and enzyme­linked immunosorbent assay analyses of the expression levels of tumor necrosis factor (TNF)­α and interleukin (IL)­1 ß were performed in these two groups. The remaining 48 rats were randomly divided into the following three groups, each containing 16 rats: Repeated injection control group (commensurable normal saline, once a week for 4 weeks), single PMA injection group (0.5 µg/µl PMA, once in the first week) and repeated injection PMA group (0.5 µg/µl PMA, once a week for 4 weeks). The expression levels of p21, detected using double immunofluorescence staining with Iba­1, and ß­galactosidase, via double immunohistochemical staining of Iba­1, were examined in these three groups. The results indicated that a single injection of PMA did not change the microglial morphology and had no significant effects on the expression levels of TNF­α and IL­1ß, compared with the control group (P>0.05). Following four repeated injections of PMA, the microglia in the substantia nigra presented with features of senescence, characterized by increased expression levels of ß-galactosidase (P<0.001) and p21 (P<0.001), compared with the repeated injection control group. In conclusion, repeated intra-nigrostriatal treatment with PMA induced microglial senescence with increased expression levels of ß-galactosidase and p21 in the substantia nigra of the rats.


Asunto(s)
Carcinógenos/toxicidad , Senescencia Celular/efectos de los fármacos , Microglía/fisiología , Sustancia Negra/efectos de los fármacos , Acetato de Tetradecanoilforbol/toxicidad , Animales , Carcinógenos/administración & dosificación , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Evaluación Preclínica de Medicamentos , Inyecciones Intraventriculares , Masculino , Enfermedad de Parkinson/patología , Ratas Sprague-Dawley , Sustancia Negra/patología , Acetato de Tetradecanoilforbol/administración & dosificación
20.
Yi Chuan ; 37(7): 720-30, 2015 07.
Artículo en Chino | MEDLINE | ID: mdl-26351172

RESUMEN

The auxin response gene family adjusts the auxin balance and the growth hormone signaling pathways in plants. Using bioinformatics methods, the auxin-response genes from the grape genome database are identified and their chromosomal location, gene collinearity and phylogenetic analysis are performed. Probable genes include 25 AUX_IAA, 19 ARF, 9 GH3 and 42 LBD genes, which are unevenly distributed on all 19 chromosomes and some of them formed distinct tandem duplicate gene clusters. The available grape microarray databases show that all of the auxin-response genes are expressed in fruit and leaf buds, and significant overexpressed during fruit color-changing, bud break and bud dormancy periods. This paper provides a resource for functional studies of auxin-response genes in grape leaf and fruit development.


Asunto(s)
Genoma de Planta , Ácidos Indolacéticos/farmacología , Reguladores del Crecimiento de las Plantas/farmacología , Vitis/genética , Secuencia de Aminoácidos , Mapeo Cromosómico , Biología Computacional , Datos de Secuencia Molecular , Familia de Multigenes , Análisis de Secuencia por Matrices de Oligonucleótidos , Filogenia
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