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1.
Genes Dev ; 32(17-18): 1155-1160, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30150254

RESUMEN

Tomato Dicer-like2 (slDCL2) is a key component of resistance pathways against potato virus X (PVX) and tobacco mosaic virus (TMV). It is also required for production of endogenous small RNAs, including miR6026 and other noncanonical microRNAs (miRNAs). The slDCL2 mRNAs are targets of these slDCL2-dependent RNAs in a feedback loop that was disrupted by target mimic RNAs of miR6026. In lines expressing these RNAs, there was correspondingly enhanced resistance against PVX and TMV. These findings illustrate a novel miRNA pathway in plants and a crop protection strategy in which miRNA target mimicry elevates expression of defense-related mRNAs.


Asunto(s)
MicroARNs/metabolismo , Virus ARN/fisiología , Ribonucleasa III/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/virología , Sistemas CRISPR-Cas , Susceptibilidad a Enfermedades , Solanum lycopersicum/enzimología , Mutación , Enfermedades de las Plantas/virología , ARN Pequeño no Traducido/metabolismo , Ribonucleasa III/genética
2.
Proc Natl Acad Sci U S A ; 119(13): e2112240119, 2022 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-35324329

RESUMEN

SignificanceParamutation involves the transfer of a repressive epigenetic mark between silent and active alleles. It is best known from exceptional non-Mendelian inheritance of conspicuous phenotypes in maize but also in other plants and animals. Recent genomic studies, however, indicate that paramutation may be less exceptional. It may be a consequence of wide-cross hybridization and may contribute to quantitative trait variation or unstable phenotypes in crops. Using the sulfurea (sulf) locus in tomato, we demonstrate that a self-reinforcing feedback loop involving DNA- and histone-methyl transferases CHROMOMETHYLTRANSFERASE3 (CMT3) and KRYPTONITE (KYP) is required for paramutation of sulf and that there is a change in chromatin organization. These findings advance the understanding of non-Mendelian inheritance in plants.


Asunto(s)
Solanum lycopersicum , Alelos , Animales , Epigénesis Genética , Solanum lycopersicum/genética , Mutación , Plantas/genética , Zea mays/genética
3.
Am J Physiol Lung Cell Mol Physiol ; 326(6): L770-L785, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38563994

RESUMEN

Novel therapies are needed for bronchopulmonary dysplasia (BPD) because no effective treatment exists. Mesenchymal stromal cell extracellular vesicles (MSC-sEVs) have therapeutic efficacy in a mouse pup neonatal hyperoxia BPD model. We tested the hypothesis that MSC-sEVs will improve lung functional and structural development in mechanically ventilated preterm lambs. Preterm lambs (∼129 days; equivalent to human lung development at ∼28 wk gestation) were exposed to antenatal steroids, surfactant, caffeine, and supported by mechanical ventilation for 6-7 days. Lambs were randomized to blinded treatment with either MSC-sEVs (human bone marrow MSC-derived; 2 × 1011 particles iv; n = 8; 4 F/4 M) or vehicle control (saline iv; 4 F/4 M) at 6 and 78 h post delivery. Physiological targets were pulse oximetry O2 saturation 90-94% ([Formula: see text] 60-90 mmHg), [Formula: see text] 45-60 mmHg (pH 7.25-7.35), and tidal volume 5-7 mL/kg. MSC-sEVs-treated preterm lambs tolerated enteral feedings compared with vehicle control preterm lambs. Differences in weight patterns were statistically significant. Respiratory severity score, oxygenation index, A-a gradient, distal airspace wall thickness, and smooth muscle thickness around terminal bronchioles and pulmonary arterioles were significantly lower for the MSC-sEVs group. S/F ratio, radial alveolar count, secondary septal volume density, alveolar capillary surface density, and protein abundance of VEGF-R2 were significantly higher for the MSC-sEVs group. MSC-sEVs improved respiratory system physiology and alveolar formation in mechanically ventilated preterm lambs. MSC-sEVs may be an effective and safe therapy for appropriate functional and structural development of the lung in preterm infants who require mechanical ventilation and are at risk of developing BPD.NEW & NOTEWORTHY This study focused on potential treatment of preterm infants at risk of developing bronchopulmonary dysplasia (BPD), for which no effective treatment exists. We tested treatment of mechanically ventilated preterm lambs with human mesenchymal stromal cell extracellular vesicles (MSC-sEVs). The results show improved respiratory gas exchange and parenchymal growth of capillaries and epithelium that are necessary for alveolar formation. Our study provides new mechanistic insight into potential efficacy of MSC-sEVs for preterm infants at risk of developing BPD.


Asunto(s)
Animales Recién Nacidos , Displasia Broncopulmonar , Vesículas Extracelulares , Pulmón , Células Madre Mesenquimatosas , Respiración Artificial , Animales , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/trasplante , Células Madre Mesenquimatosas/metabolismo , Pulmón/metabolismo , Pulmón/patología , Respiración Artificial/efectos adversos , Respiración Artificial/métodos , Ovinos , Displasia Broncopulmonar/patología , Displasia Broncopulmonar/terapia , Displasia Broncopulmonar/metabolismo , Humanos , Femenino
4.
Rheumatology (Oxford) ; 63(3): 689-697, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37279721

RESUMEN

OBJECTIVES: The relationship between smoking and RA has been confirmed. Most nations have ratified the Framework Convention on Tobacco Control. However, there are considerable regional differences in how effectively tobacco control measures were implemented. This study was carried out to estimate the spatiotemporal trends of smoking-related RA burdens. METHODS: Data were available from the Global Burden of Disease Study 2019 and were analysed by age, sex, year and region. Joinpoint regression analysis was applied to the analysis of temporal trends in the RA burden resulting from smoking over 30 years. RESULTS: From 1990 to 2019, the number of global RA cases increased each year. The age-standardized prevalence, death and disability-adjusted life-year (DALY) rates also increased. However, there was a wave in the changing trend of the age-standardized death rate, with the lowest point in 2012 and the highest point in 1990. Smoking, in particular, was responsible for 11.9% of total RA deaths and 12.8% of total DALYs in 1990 but only 8.5% of total RA deaths and 9.6% of total DALYs in 2019. A greater burden from smoking exposure was borne by men, older adults and people living in high-middle and high sociodemographic index (SDI) countries and regions. Moreover, the UK demonstrated the highest reduction in age-standardized death and DALY rates over the three decades. CONCLUSION: There were reductions in the age-standardized burdens of RA caused by smoking worldwide. Nevertheless, this continues to be an issue in some areas, and efforts to reduce smoking should be made to lessen this growing burden.


Asunto(s)
Artritis Reumatoide , Procedimientos de Cirugía Plástica , Masculino , Humanos , Anciano , Fumar/epidemiología , Artritis Reumatoide/epidemiología , Percepción Social
5.
Plant Physiol ; 191(1): 335-351, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36200851

RESUMEN

RNA-directed DNA methylation (RdDM) is an epigenetic process that directs silencing to specific genomic regions and loci. The biological functions of RdDM are not well studied in horticultural plants. Here, we isolated the ethyl methane-sulfonate-induced mutant reduced organ size (ros) producing small leaves, flowers, and fruits in woodland strawberry (Fragaria vesca) due to reduced cell numbers compared with that in the wild-type (WT). The candidate mutation causes a premature stop codon in FvH4_6g28780, which shares high similarity to Arabidopsis (Arabidopsis thaliana) Factor of DNA Methylation1 (FDM1) encoding an RdDM pathway component and was named FveFDM1. Consistently, the fvefdm1CR mutants generated by CRISPR/Cas9 also produced smaller organs. Overexpressing FveFDM1 in an Arabidopsis fdm1-1 fdm2-1 double mutant restored DNA methylation at the RdDM target loci. FveFDM1 acts in a protein complex with its homolog Involved in De Novo 2 (FveIDN2). Furthermore, whole-genome bisulfite sequencing revealed that DNA methylation, especially in the CHH context, was remarkably reduced throughout the genome in fvefdm1. Common and specific differentially expressed genes were identified in different tissues of fvefdm1 compared to in WT tissues. DNA methylation and expression levels of several gibberellic acid (GA) biosynthesis and cell cycle genes were validated. Moreover, the contents of GA and auxin were substantially reduced in the young leaves of fvefdm1 compared to in the WT. However, exogenous application of GA and auxin could not recover the organ size of fvefdm1. In addition, expression levels of FveFDM1, FveIDN2, Nuclear RNA Polymerase D1 (FveNRPD1), Domains Rearranged Methylase 2 (FveDRM2), and cell cycle genes were greatly induced by GA treatment. Overall, our work demonstrated the critical roles of FveFDM1 in plant growth and development via RdDM-mediated DNA methylation in horticultural crops.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Fragaria , Metilación de ADN/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Fragaria/genética , Fragaria/metabolismo , Proteínas de Arabidopsis/metabolismo , Tamaño de los Órganos/genética , Regulación de la Expresión Génica de las Plantas , ARN Interferente Pequeño/genética , ADN de Plantas/metabolismo
6.
Int Orthop ; 48(3): 683-692, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37740768

RESUMEN

PURPOSE: Total knee arthroplasty is the main method for the treatment of advanced haemophilic knee arthritis. Due to the particularity of hemophilia, the blood management plan is the focus of the perioperative period for haemophilia patients. This study aimed to investigate the clinical effect and safety of intra-articular injection of tranexamic acid in patients with haemophilia. METHODS: This is a retrospective study. According to whether tranexamic acid is used or not, patients are divided into tranexamic acid group (n=30) and non-tranexamic acid group (n=29). Total blood loss, intraoperative blood loss, complete blood count, total amount of coagulation factor VIII (FVIII) usage, coagulation biomarkers, inflammatory biomarkers, knee range of motion, knee joint function, pain status, complication rate, and patient satisfaction were assessed and compared at a mean follow-up of 16 months. RESULTS: Injecting tranexamic acid into the knee joint cavity can effectively reduce the hidden blood loss and total blood loss (P<0.001), and reduce the patient's early postoperative inflammation biomarkers, pain status, and limb swelling. Therefore, the patient can obtain a better range of motion following total knee arthroplasty. In the long run, in terms of joint function and surgical satisfaction, there are no statistically significant differences. In addition, there are no statistically significant differences between the two groups of patients in terms of the total amount of FVIII usage, length of stay, and hospitalization expenses. CONCLUSION: In patients with haemophilia, intra-articular injection of tranexamic acid during total knee arthroplasty can effectively reduce postoperative blood loss, early postoperative inflammation levels, pain and limb swelling, and enable patients to receive higher-quality rehabilitation exercises to get better joint function. Previous studies on TKA in haemophilic patients have already demonstrated the efficacy of intra-articular injections of TXA in reducing postoperative blood loss. Our study confirms this efficacy.


Asunto(s)
Antifibrinolíticos , Artritis , Artroplastia de Reemplazo de Rodilla , Hemofilia A , Ácido Tranexámico , Humanos , Ácido Tranexámico/uso terapéutico , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Rodilla/métodos , Estudios Retrospectivos , Hemofilia A/complicaciones , Hemofilia A/tratamiento farmacológico , Antifibrinolíticos/uso terapéutico , Pérdida de Sangre Quirúrgica/prevención & control , Hemorragia Posoperatoria/etiología , Inyecciones Intraarticulares , Inflamación/complicaciones , Biomarcadores , Dolor
7.
J Environ Manage ; 354: 120353, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38377756

RESUMEN

Waste beverages are utilized as resources in various valuable, albeit energy-consuming, waste-to-energy processes. There is a growing need for alternative cost-effective methods to harness their potential. This study explored the feasibility of employing waste beverages as feedstock for the counterpart component of a TiO2-based composite photocatalyst. Several commonly available carbonated soft drinks from the Japanese market have been investigated to achieve this goal. The investigation revealed that a mild hydrothermal treatment condition could transform all examined beverages into carbonaceous materials suitable for fabricating a core-shell structure with TiO2, resulting in a remarkably efficient visible light active photocatalyst. Notably, a pH-adjusted photocatalyst derived from Coca Cola® exhibited superior visible light photodegradability toward dye molecules and enhanced bactericidal efficacy compared to the counterpart derived from pure sucrose. The heightened visible light photocatalytic activity can be attributed to the distinctive carboxy-rich surface functional groups, based on the findings of experimental analyses and density functional theory calculations. The bidentate-type bonding of these groups with TiO2 induces a modified interfacial bond structure that facilitates the efficient transfer of photoexcited carriers. This study presents a novel avenue for the effective utilization and recycling of waste beverages, and adds value under environmentally benign conditions.


Asunto(s)
Carbono , Nanoestructuras , Luz , Nanoestructuras/química , Antibacterianos , Bebidas
8.
BMC Cancer ; 23(1): 808, 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37644421

RESUMEN

BACKGROUND: Glioblastoma (GBM) is the most malignant glioma, with poor survival rates and prognosis. Several studies have reported the abnormal expression of circular RNAs (circRNAs) and their functions in the malignant biological behavior of GBM. However, such research is still in the preliminary stages, and further study is needed to confirm the therapeutic potential of circRNAs in GBM. METHODS: RNA-seq was performed using four tumor tissues from patients with GBM and their adjacent non-tumor brain tissues to screen differentially expressed circRNAs. Fluorescence in situ hybridization assay was used to examine the location of circ_0021350 in glioma cells. In addition, a series of biological function assays were employed to verify the oncogenic role of circ_0021350 in GBM. Quantitative reverse transcription PCR was used to examine circular, micro- (miRNA), and messenger RNA (mRNA) levels. Furthermore, dual-luciferase reporter, RNA pull-down, and RNA binding protein immunoprecipitation assays were applied to verify the interaction between circ_0021350 and its downstream effectors. RESULTS: Circ_0021350 was significantly elevated in GBM tissues and glioma cells. Overexpression of circ_0021350 promoted glioma cell proliferation and metastatic ability; silencing of circ_0021350 had the opposite effect. Mechanistic analysis revealed that circ_0021350 sponged miR-1207-3p to regulate PIK3R3, whose overexpression reversed the reduction in the malignant biological behavior of glioma cells caused by silencing circ_0021350. CONCLUSION: Our findings suggest that circ_0021350 is an oncogenic circRNA in GBM, and the circ_0021350/miR-1207-3p/PIK3R3 axis may serve as a potential therapeutic target in GBM treatment.


Asunto(s)
Glioblastoma , Glioma , MicroARNs , Humanos , Glioblastoma/genética , Hibridación Fluorescente in Situ , ARN Circular/genética , Oncogenes , MicroARNs/genética , Fosfatidilinositol 3-Quinasas
9.
Pediatr Res ; 93(6): 1528-1538, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36030318

RESUMEN

BACKGROUND: Low levels of insulin-like growth factor-1 (IGF-1) protein in preterm human infants are associated with bronchopulmonary dysplasia (BPD). We used our preterm lamb model of BPD to determine (1) dosage of recombinant human (rh) IGF-1 bound to binding protein-3 (IGFBP-3) to reach infant physiologic plasma levels; and (2) whether repletion of plasma IGF-1 improves pulmonary and cardiovascular outcomes. METHODS: Group 1: normal, unventilated lambs from 128 days gestation through postnatal age 5 months defined normal plasma levels of IGF-1. Group 2: continuous infusion of rhIGF-1/rhIGFBP-3 (0.5, 1.5, or 4.5 mg/kg/day; n = 2) for 3 days in mechanically ventilated (MV) preterm lambs determined that 1.5 mg/kg/day dosage attained physiologic plasma IGF-1 concentration of ~125 ng/mL, which was infused in four more MV preterm lambs. RESULTS: Group 1: plasma IGF-1 protein increased from ~75 ng/mL at 128 days gestation to ~220 ng/L at 5 months. Group 2: pilot study of the optimal dosage (1.5 mg/kg/day rhIGF-1/rhIGFBP-3) in six MV preterm lambs significantly improved some pulmonary and cardiovascular outcomes (p < 0.1) compared to six MV preterm controls. RhIGF-1/rhIGFBP-3 was not toxic to the liver, kidneys, or lungs. CONCLUSIONS: Three days of continuous iv infusion of rhIGF-1/rhIGFBP-3 at 1.5 mg/kg/day improved some pulmonary and cardiovascular outcomes without toxicity. IMPACT: Preterm birth is associated with rapid decreases in serum or plasma IGF-1 protein level. This decline adversely impacts the growth and development of the lung and cardiovascular system. For this pilot study, continuous infusion of optimal dosage of rhIGF-1/rhIGFBP-3 (1.5 mg/kg/day) to maintain physiologic plasma IGF-1 level of ~125 ng/mL during mechanical ventilation for 3 days statistically improved some structural and biochemical outcomes related to the alveolar formation that would favor improved gas exchange compared to vehicle-control. We conclude that 3 days of continuous iv infusion of rhIGF-1/rhIGFBP-3 improved some physiological, morphological, and biochemical outcomes, without toxicity, in mechanically ventilated preterm lambs.


Asunto(s)
Displasia Broncopulmonar , Nacimiento Prematuro , Lactante , Femenino , Humanos , Animales , Recién Nacido , Ovinos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Displasia Broncopulmonar/tratamiento farmacológico , Proyectos Piloto , Recien Nacido Prematuro , Proteínas Recombinantes/metabolismo , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Oveja Doméstica
10.
BMC Musculoskelet Disord ; 24(1): 946, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057748

RESUMEN

BACKGROUND: Haemophilic arthropathy (HA) is a common comorbidity of haemophilia. Some people with haemophilia (PWH) were human immunodeficiency virus (HIV)-positive. Arthroplasty is an effective treatment for end-stage HA. This study was carried out to report the effectiveness and satisfaction following total hip arthroplasty (THA) or total knee arthroplasty (TKA) in PWH with HIV. PATIENTS AND METHODS: All patients with haemophilia and HIV undergoing THA or TKA in our centre from January 2015 to June 2020 were reviewed. All patients were followed for at least twenty-four months. The improvements in postoperative indicators were evaluated at the latest follow-up, including the Visual Analogue Scale (VAS) score, range of motion (ROM), and validated joint scores such as Knee Society Score (KSS; clinical and functional) and Harris Hip Score (HHS). The complications and satisfaction were analysed likewise. Those were utilized to weigh the risks and benefits of the procedure in the population. RESULTS: Fourteen patients (7 hips and 14 knees) were included in the study. The follow-up of the THA cohort was 53.3 months (range, 27-82) and the TKA cohort was 50.1 months (range, 25-85), respectively. The average VAS score was ameliorated from 7.3 to 3.0 and 6.6 to 2.8 in the two groups (P < .001, respectively). Similarly, two cohorts (THA and TKA) showed statistically significant changes in the extension and flexion ROM between the preoperative and the latest follow-up (P < .05, P < .001, respectively). Besides, statistically significant differences between the preoperative and final follow-up values of HHS (from 41.6 to 82.3), clinical KSS (from 34.8 to 72.8), and functional KSS (from 42.9 to 73.2) were observed (P < .001, respectively). Notably, there were 4 complications noted among 21 arthroplasties performed, giving a 19.0% complication rate. Based on the satisfaction score, the majority of patients were optimistic about the arthroplasty. CONCLUSION: Given these findings, THA or TKA of the PWH with HIV is a worthwhile procedure and can be performed by an experienced and collaborative multidisciplinary team in a tertiary centre with a good haemophilia care system.


Asunto(s)
Artritis , Artroplastia de Reemplazo de Rodilla , Infecciones por VIH , Hemofilia A , Hepatitis C , Humanos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Rodilla/métodos , Hemofilia A/complicaciones , Hemofilia A/epidemiología , Hemofilia A/cirugía , Articulación de la Rodilla/cirugía , Estudios de Seguimiento , Resultado del Tratamiento , Hepatitis C/complicaciones , Hepatitis C/cirugía , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Infecciones por VIH/cirugía , Estudios Retrospectivos
11.
Chaos ; 32(6): 061101, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35778124

RESUMEN

Science and technology capability refers to the comprehensive capability of all factors that affect the development of science and technology, mainly referring to human and material factors related to science and technology, among which human resources are the foundation and driving force. Therefore, researchers become a unique research perspective for the evaluation of national science and technology capabilities. Taking the integrated circuit field as the analysis case, this article proposed a researchers' transfer network model based on the online open source literature database. From the published literature information, the model obtains the researchers' transfer network that has a core-periphery structure. The core nodes are the European Union, the United States, China, etc., and these nodes are the most closely connected. A country/region role evolution model is also proposed, which reveals the characteristics of the role evolution of the European Union, the United States, China, and other countries from the perspective of researchers' transfer, especially their transfer between countries.


Asunto(s)
Tecnología , China , Unión Europea , Humanos , Estados Unidos
12.
J Orthop Traumatol ; 23(1): 31, 2022 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-35819639

RESUMEN

BACKGROUND: Haemophilic arthropathy (HA), a common complication of haemophilia, is secondary to recurrent joint bleeding and increases the prevalence of end-stage osteoarthritis (OA). Total knee arthroplasty (TKA) is a reliable treatment for haemophilia patients. This study was performed to evaluate the mid-term outcomes of TKA for end-stage HA. We hypothesized that the rate of complications of TKA is higher for patients with haemophilia than for patients without haemophilia. METHODS: Patients with HA undergoing TKA from January 2015 to December 2016 in our centre were retrospectively reviewed. All patients were managed by a multidisciplinary team. The improvements in flexion contracture, range of motion (ROM), Knee Society Score (KSS; clinical and functional), Visual Analogue Scale (VAS) score, and satisfaction at final follow-up were analysed to evaluate the effectiveness of TKA in HA. The complications were analysed to evaluate the safety of TKA in HA. RESULTS: Twenty-eight patients (32 knees) were included in the study. The follow-up was 69.1 ± 5.1 months. Significant differences between the preoperative and final follow-up values of flexion contracture (which changed from 21.1 ± 6.5° to 14.3 ± 4.1°, P < 0.001), ROM (from 53.9 ± 15.0° to 70.3 ± 16.3°, P < 0.001), clinical KSS (from 33.5 ± 14.4° to 62.7 ± 9.5°, P < 0.001), functional KSS (from 46.1 ± 15.5° to 62.9 ± 9.7°, P < 0.001), and VAS score (from 6.8 ± 1.4 to 4.9 ± 1.3, P < 0.01) were observed. Importantly, the incidence of complications was 15.6% and the satisfaction was 100% in our mid-term study. CONCLUSION: Under elaborative and comprehensive management, TKA is effective and safe in patients with advanced HA on the basis of mid-term follow-up outcomes.


Asunto(s)
Artritis , Artroplastia de Reemplazo de Rodilla , Contractura , Hemofilia A , Artritis/etiología , Artroplastia de Reemplazo de Rodilla/efectos adversos , Contractura/etiología , Estudios de Seguimiento , Hemofilia A/complicaciones , Hemofilia A/cirugía , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
13.
Am J Physiol Lung Cell Mol Physiol ; 321(1): L248-L262, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34009031

RESUMEN

Invasive mechanical ventilation (IMV) and exposure to oxygen-rich gas during early postnatal life are contributing factors for long-term pulmonary morbidities faced by survivors of preterm birth and bronchopulmonary dysplasia. The duration of IMV that leads to long-term pulmonary morbidities is unknown. We compared two durations of IMV (3 h vs. 6 days) during the first 6-7 days of postnatal life in preterm lambs to test the hypothesis that minimizing the duration of IMV will improve long-term respiratory system mechanics and structural outcomes later in life. Moderately preterm (∼85% gestation) lambs were supported by IMV for either 3 h or 6 days before weaning from all respiratory support to become former preterm lambs. Respiratory system mechanics and airway reactivity were assessed monthly from 1 to 6 mo of chronological postnatal age by the forced oscillation technique. Quantitative morphological measurements were made for smooth muscle accumulation around terminal bronchioles and indices of alveolar formation. Minimizing IMV to 3 h led to significantly better (P < 0.05) baseline respiratory system mechanics and less reactivity to methacholine in the first 3 mo of chronological age (2 mo corrected age), significantly less (P < 0.05) accumulation of smooth muscle around peripheral resistance airways (terminal bronchioles), and significantly better (P < 0.05) alveolarization at the end of 5 mo corrected age compared with continuous IMV for 6 days. We conclude that limiting the duration of IMV following preterm birth of fetal lambs leads to better respiratory system mechanics and structural outcomes later in life.


Asunto(s)
Pulmón/fisiopatología , Respiración Artificial/métodos , Respiración , Insuficiencia Respiratoria/terapia , Animales , Animales Recién Nacidos , Femenino , Masculino , Embarazo , Ovinos
14.
Pain Pract ; 21(5): 588-593, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33314724

RESUMEN

BACKGROUND: In a minority of cases, foramen ovales (FOs) are difficult to access due to single confounding anatomical variations. However, there is no method reported where the FO has been successfully targeted via a single puncture in the presence of two or more anatomical variations. OBJECTIVES: To observe the effect of a new stereotactic bidirectional approach guiding technique utilized in a patient who harbored a particularly difficult-to-access FO due to multiple anatomical variations. METHODS: During operation of a unique facial entry point's trigeminal neuralgia patient, make one plane which identified by a three-dimensional (3D) coordinates of the FO target and arc angle value on stereotactic frame, make this plane intersected with another plane which determined by the 3D CT-reconstruction's facial entry point data on a ruler, so as to elucidate the appropriate trajectory. The authors coined the approach "Air-to-air meeting" method. RESULTS: We completed the radiofrequency thermocoagulation (RFT) with a single puncture to successfully target the FO according to the preoperative plan confirmed by C-arm radiography. Postoperative pain scores using a visual analog scale decreased from 10 to 3 by the first day after the procedure. There were no permanent complications or morbidity from the surgery. CONCLUSIONS: To the authors' knowledge, this is the first report describing a unique facial entry point determined by this technique for the treatment of a patient with trigeminal neuralgia.


Asunto(s)
Neuralgia del Trigémino , Electrocoagulación , Humanos , Dimensión del Dolor , Ondas de Radio , Neuralgia del Trigémino/cirugía
15.
Biomed Eng Online ; 19(1): 7, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32013979

RESUMEN

BACKGROUND: Cochlear implants (CIs) have become important for the treatment of severe-to-profound sensorineural hearing loss (SNHL). Meanwhile, electrically evoked compound action potentials (ECAPs) and electrically evoked auditory brainstem responses (EABRs), which can be examined and evaluated with minimal patient cooperation, have become more reliable for tone measurement and speech recognition postoperatively. However, few studies have compared the electrophysiological characteristics of the auditory nerve using ECAPs and EABRs under different functional states of the auditory nerve (FSANs). We used guinea pig models in which six electrodes were implanted unilaterally with continuous electrical stimulation (ES) for 4 h. The amplitude growth functions (AGFs) of the alternating polarity ECAP (AP-ECAP) and forward-masking subtraction ECAP (FM-ECAP), as well as the EABR waves under "normal" and "abnormal" FSANs, were obtained. RESULTS: Both the AP-ECAP and FM-ECAP thresholds were significantly higher than those measured by EABR under both "normal" FSAN and "abnormal" FSANs (p < 0.05). There was a significant difference in the slope values between electrodes 1 and 2 and electrodes 3 and 4 in terms of the AP-ECAP under the "abnormal" FSAN (p < 0.05). The threshold gaps between the AP-ECAP and FM-ECAP were significantly larger under the "abnormal" FSAN than under the "normal" FSAN (p < 0.05). CONCLUSIONS: Both of the ECAP thresholds were higher than the EABR thresholds. The AP-ECAP was more sensitive than the FM-ECAP under the "abnormal" FSAN.


Asunto(s)
Nervio Coclear/fisiopatología , Animales , Tronco Encefálico/fisiopatología , Implantes Cocleares , Estimulación Eléctrica , Electrodos , Potenciales Evocados Auditivos , Cobayas , Límite de Detección
16.
J Chem Phys ; 152(4): 044702, 2020 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-32007048

RESUMEN

Surface chemistry and photochemistry of small molecules on the rutile TiO2(001) and TiO2(011)-(2 × 1) surfaces were studied by low energy electron diffraction, thermal desorption spectroscopy, and x-ray photoelectron spectroscopy. It was found that the TiO2(001) surface mainly exhibits the defects of Ti interstitials in the near-surface region, while the TiO2(011)-(2 × 1) surface mainly exhibits the defects of double-oxygen vacancies. The defect structures of TiO2 surfaces strongly affect their adsorption and thermal/photodesorption behaviors. On the TiO2(001) surface, CH3OH and H2O dissociatively adsorb at the surface Ti sites near Ti interstitials; O2 molecularly adsorbs at the surface Ti sites adjacent to Ti interstitials, forming photoactive O2 species that undergoes a hole-mediated photodesorption process; CO adsorbs at the nearest surface Ti sites close to the Ti interstitials, but CO2 does not, and the resulting CO species is photoactive; and both CO and CO2 species adsorbed at the normal Ti4+ sites are photoinactive. On the TiO2(011)-(2 × 1) surface, O2 adsorbs only at the double-oxygen vacancy sites, and the resulting O2 species dissociates to form two oxygen atoms to refill in the oxygen vacancies upon heating; CO2 adsorbs at the double-oxygen vacancy sites, but CO does not, and the resulting CO2 species is photoactive; and both CO and CO2 species adsorbed at the surface Ti4+ sites are photoinactive. These results broaden the fundamental understandings of the chemistry and photochemistry of TiO2 surfaces, and the established structure-reactivity relation of small molecules on TiO2 surfaces is useful in probing complex structures of TiO2 powder catalysts.

17.
Chem Rec ; 19(7): 1393-1406, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30548140

RESUMEN

The enhancement of photocatalytic activity of TiO2 can be made either by promoting absorption efficiency of photon energy or by reducing recombination losses of photogenerated charge carriers, for which fabrication of nanocomposite structure with carbon materials is an optional selection. Among various nanocarbons, graphene (G), graphene oxide (GO), and reduced graphene oxide (rGO) are more favorable as the counterpart materials because they can provide availability of both obverse and reverse surface, thus doubling effective sites for adsorption, loading of nanoparticles, and interfacial interaction with the loaded nanoparticles. Composition of G/GO with titania, therefore, is a hopeful strategy for achieving synergy or cooperative effect in photocatalysis. In this personal account, we focus on the background and methodology of several soft chemical approaches that we have utilized up to date to fabricate nanocomposites of G/GO and titania, aiming to shed light on the importance of designing of nanocomposite structure for enhancing photocatalysis. In addition, we emphasize the role of interfacial interaction between carbon and titania by exemplifying a hybridized photocatalyst based on inexpensive biomass-derived carbon sphere (CS), and demonstrate that it is a crucial influential factor underlying an enhanced visible light photocatalysis. CS can be a better selection as a counterpart component than G/GO, whose core-shell composing structure with titania (TiO2 @CS) can efficiently induce charge transfer so as to achieve a much higher photocatalytic performance under visible light illumination as compared to the composite of rGO and titania.

18.
Am J Physiol Lung Cell Mol Physiol ; 315(5): L816-L833, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30211655

RESUMEN

Preterm birth and mechanical ventilation (MV) frequently lead to bronchopulmonary dysplasia, the histopathological hallmark of which is alveolar simplification. How developmental immaturity and ongoing injury, repair, and remodeling impact completion of alveolar formation later in life is not known, in part because of lack of suitable animal models. We report a new model, using former-preterm lambs, to test the hypothesis that they will have persistent alveolar simplification later in life. Moderately preterm lambs (~85% gestation) were supported by MV for ~6 days before being transitioned from all respiratory support to become former-preterm lambs. Results are compared with term control lambs that were not ventilated, and between males (M) and females (F). Alveolar simplification was quantified morphometrically and stereologically at 2 mo (4 M, 4 F) or 5 mo (4 M, 6 F) corrected postnatal age (cPNA) compared with unventilated, age-matched term control lambs (4 M, 4 F per control group). These postnatal ages in sheep are equivalent to human postnatal ages of 1-2 yr and ~6 yr, respectively. Multivariable linear regression results showed that former-preterm lambs at 2 or 5 mo cPNA had significantly thicker distal airspace walls ( P < 0.001 and P < 0.009, respectively), lower volume density of secondary septa ( P < 0.007 and P < 0.001, respectively), and lower radial alveolar count ( P < 0.003 and P < 0.020, respectively) compared with term control lambs. Sex-specific differences were not detected. We conclude that moderate preterm birth and MV for ~6 days impedes completion of alveolarization in former-preterm lambs. This new model provides the opportunity to identify underlying pathogenic mechanisms that may reveal treatment approaches.


Asunto(s)
Displasia Broncopulmonar/patología , Pulmón/patología , Animales , Animales Recién Nacidos , Femenino , Edad Gestacional , Masculino , Modelos Animales , Respiración Artificial/métodos , Ovinos
19.
Amino Acids ; 50(2): 241-253, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29098406

RESUMEN

Following the exploration of biochemicals in amphibian defensive skin secretion, great attention has been focused on the novel bioactive peptides with unique molecular structures and complicated features and functions. In this study, the skin secretion of Oriental fire-bellied toad, Bombina orientalis, was acquired to search peptides with therapeutic potential. Using "shotgun" cloning technique, a full-length peptide precursor co-encoding two novel bombinin peptides was cloned from the skin secretion-derived cDNA library of B. orientalis. The deduced peptides were identified as one bombinin-like peptide (BLP) (GIGSAILSAGKSIIKGLAKGLAEHF-NH2) and one bombinin H-type peptide (BH) (IIGPVLGLVGKALGGLL-NH2). The primary structures of both peptides were confirmed through reverse-phase HPLC fractionation and mass spectrometry. Secondary structural prediction revealed Bombinin-BO1 and Bombinin H-BO1 adopted α-helical structural features. In addition, the two peptides exhibited broad-spectrum antimicrobial effect against Gram-positive and Gram-negative bacteria and yeast. Meanwhile, the anticancer activity assay indicated both peptides exerted significant anticancer effects against human hepatoma cell lines tested (Hep G2/SK-HEP-1/Huh7). The peptides reported here for the first time may represent novel lead compounds for the design/development of new therapeutics for human infection and neoplastic disease.


Asunto(s)
Proteínas Anfibias/farmacología , Antiinfecciosos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Anuros/metabolismo , Piel/metabolismo , Secuencia de Aminoácidos , Proteínas Anfibias/síntesis química , Proteínas Anfibias/química , Animales , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Péptidos Catiónicos Antimicrobianos/síntesis química , Péptidos Catiónicos Antimicrobianos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Clonación Molecular , ADN Complementario/genética , Hemólisis/efectos de los fármacos , Humanos , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Estructura Secundaria de Proteína , Piel/química
20.
Phys Chem Chem Phys ; 20(11): 7508-7513, 2018 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-29488520

RESUMEN

In this study, we used DFT calculations to investigate the bi-functional nature of Cu-based alloy nanoclusters (NCs) supported on CeO2(111) for CO oxidation. More specifically, we studied the reaction pathways on Cu3Pt7 and Cu3Rh7via the O2 associative (OCOO) and dissociative mechanisms. We find that CO oxidation on Cu3Pt7 proceeds via the O2 dissociation pathway, while Cu3Rh7 prefers the OCOO mechanism. Combined with our previous results on Cu3Au7, we find that bi-functional CO oxidation on Cu-based alloys follows a Brønsted-Evans-Polanyi relationship, which provides a useful metric for the design of bi-functional alloyed catalysts.

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