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1.
Invest Ophthalmol Vis Sci ; 64(15): 4, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38047739

RESUMEN

Purpose: The aim of this study was to investigate whether there is any association between the levels of the angiogenic growth factors and the vascular oxygen saturation in eyes with diabetic retinopathy. Methods: The study was designed as a prospective trial. The cohort consisted of 29 diabetic patients with scheduled vitreous procedures (intravitreal injection or pars plana vitrectomy). The control group included 30 patients scheduled for macular surgery (macular hole or epiretinal membrane). Nine patients (four from the diabetic maculopathy [DM] group and five from the control group) were excluded from the study because of unsuccessful vitreous samples. Retinal oximetry was performed several hours before the vitreous procedure was performed, and vitreous samples were obtained during the procedure. The concentrations of VEGF, Serpin F1/pigment epithelium-derived factor (PEDF), and placental growth factor (PlGF) were measured by ELISA. Results: A negative correlation between level of VEGF and arteriovenous (AV) saturation difference was determined in the DM group (Pearson correlation coefficient r = -0.607; two-tailed test, P = 0.002). Also a negative correlation between level of PlGF and AV saturation difference was determined in the DM group (Pearson correlation coefficient r = -0.521; two-tailed test, P = 0.011) A positive correlation between PlGF level and the vein saturation was not statistically significant (Pearson correlation coefficient r = 0.325; two-tailed test, P = 0.130). We did not find any correlation between vitreous level of PEDF and vascular saturation within the DM group. Conclusions: Our findings in diabetic patients suggests a correlation between the intravitreal level of proangiogenic factors and the AV difference measured by retinal oximetry.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Humanos , Femenino , Saturación de Oxígeno , Estudios Prospectivos , Factor A de Crecimiento Endotelial Vascular , Factor de Crecimiento Placentario , Vasos Retinianos , Retina
2.
Microbiol Spectr ; 11(4): e0164823, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37358458

RESUMEN

Noncanonical secondary structures in nucleic acids have been studied intensively in recent years. Important biological roles of cruciform structures formed by inverted repeats (IRs) have been demonstrated in diverse organisms, including humans. Using Palindrome analyser, we analyzed IRs in all accessible bacterial genome sequences to determine their frequencies, lengths, and localizations. IR sequences were identified in all species, but their frequencies differed significantly across various evolutionary groups. We detected 242,373,717 IRs in all 1,565 bacterial genomes. The highest mean IR frequency was detected in the Tenericutes (61.89 IRs/kbp) and the lowest mean frequency was found in the Alphaproteobacteria (27.08 IRs/kbp). IRs were abundant near genes and around regulatory, tRNA, transfer-messenger RNA (tmRNA), and rRNA regions, pointing to the importance of IRs in such basic cellular processes as genome maintenance, DNA replication, and transcription. Moreover, we found that organisms with high IR frequencies were more likely to be endosymbiotic, antibiotic producing, or pathogenic. On the other hand, those with low IR frequencies were far more likely to be thermophilic. This first comprehensive analysis of IRs in all available bacterial genomes demonstrates their genomic ubiquity, nonrandom distribution, and enrichment in genomic regulatory regions. IMPORTANCE Our manuscript reports for the first time a complete analysis of inverted repeats in all fully sequenced bacterial genomes. Thanks to the availability of unique computational resources, we were able to statistically evaluate the presence and localization of these important regulatory sequences in bacterial genomes. This work revealed a strong abundance of these sequences in regulatory regions and provides researchers with a valuable tool for their manipulation.


Asunto(s)
Replicación del ADN , Genómica , Humanos , Secuencia de Bases , Bacterias/genética , Filogenia
3.
Biochimie ; 208: 93-99, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36549455

RESUMEN

The p53 protein is a key tumor suppressor and the most commonly mutated and down-regulated protein in human tumors. It functions mainly through interaction with DNA, and p53 acts as a transcription factor that recognizes the so-called p53 target sites on the promoters of various genes. P53 has been shown to exist as many isoforms, including three C-terminal isoforms that are produced by alternative splicing. Because the C-terminal domain is responsible for sequence-nonspecific binding and regulation of p53 binding, we have analyzed DNA recognition by these C-terminal isoforms. Using atomic force microscopy, we show for the first time that all C-terminal isoforms recognize superhelical DNA. It is particularly noteworthy that a sequence-specific p53 consensus binding site is bound by p53α and ß isoforms with similar affinities, whilst p53α shows higher binding to a quadruplex sequence than both p53ß and p53γ, and p53γ loses preferential binding to both the consensus binding sequence and the quadruplex-forming sequence. These results show the important role of the variable p53 C-terminal amino acid sequences for DNA recognition.


Asunto(s)
Empalme Alternativo , Proteína p53 Supresora de Tumor , Humanos , Proteína p53 Supresora de Tumor/metabolismo , Secuencia de Bases , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ADN/genética , ADN/metabolismo
4.
Front Neurol ; 13: 954712, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36388199

RESUMEN

Introduction: While the role of physiotherapy as part of a comprehensive inpatient rehabilitation is indisputable, clear evidence concerning the effectiveness of different rehabilitation managements [interdisciplinary implementing the International Classification of Functioning, disability and health (ICF) vs. multidisciplinary model] and physiotherapy categories (neuroproprioceptive "facilitation, inhibition" vs. motor/skill acquisitions using technologies) are still lacking. In this study, four kinds of comprehensive inpatient rehabilitation with different management and content of physical therapy will be compared. Moreover, focus will be placed on the identification of novel biological molecules reflective of effective rehabilitation. Long non-coding RNAs (lncRNAs) are transcripts (>200 bps) of limited coding potential, which have recently been recognized as key factors in neuronal signaling pathways in ischemic stroke and as such, may provide a valuable readout of patient recovery and neuroprotection during therapeutic progression. Methods and analysis: Adults after the first ischemic stroke in an early sub-acute phase with motor disability will be randomly assigned to one of four groups and undergo a 3 weeks comprehensive inpatient rehabilitation of different types: interdisciplinary team work using ICF model as a guide; multidisciplinary teamwork implementing neuroproprioceptive "facilitation and inhibition" physiotherapy; multidisciplinary teamwork implementing technology-based physiotherapy; and standard multidisciplinary teamwork. Primary (the Goal Attainment Scale, the Patient-Reported Outcomes Measurement Information System, and the World Health Organization Disability Assessment Schedule) and secondary (motor, cognitive, psychological, speech and swallowing functions, functional independence) outcomes will be measured. A blood sample will be obtained upon consent (20 mls; representing pre-rehabilitation molecular) before and after the inpatient program. Primary outcomes will be followed up again 3 and 12 months after the end of the program. The overarching aim of this study is to determine the effectiveness of various rehabilitation managements and physiotherapeutic categories implemented by patients post ischemic stroke via analysis of primary, secondary and long non-coding RNA readouts. This clinical trial will offer an innovative approach not previously tested and will provide new complex analysis along with public assessable molecular biological evidence of various rehabilitation methodology for the alleviation of the effects of ischemic stroke. Clinical trial registration: NCT05323916, https://clinicaltrials.gov/ct2/show/NCT05323916.

5.
Int J Mol Sci ; 22(23)2021 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-34884661

RESUMEN

R-loops are common non-B nucleic acid structures formed by a three-stranded nucleic acid composed of an RNA-DNA hybrid and a displaced single-stranded DNA (ssDNA) loop. Because the aberrant R-loop formation leads to increased mutagenesis, hyper-recombination, rearrangements, and transcription-replication collisions, it is regarded as important in human diseases. Therefore, its prevalence and distribution in genomes are studied intensively. However, in silico tools for R-loop prediction are limited, and therefore, we have developed the R-loop tracker tool, which was implemented as a part of the DNA Analyser web server. This new tool is focused upon (1) prediction of R-loops in genomic DNA without length and sequence limitations; (2) integration of R-loop tracker results with other tools for nucleic acids analyses, including Genome Browser; (3) internal cross-evaluation of in silico results with experimental data, where available; (4) easy export and correlation analyses with other genome features and markers; and (5) enhanced visualization outputs. Our new R-loop tracker tool is freely accessible on the web pages of DNA Analyser tools, and its implementation on the web-based server allows effective analyses not only for DNA segments but also for full chromosomes and genomes.


Asunto(s)
Algoritmos , ADN/química , ADN/genética , Inestabilidad Genómica , Genómica/métodos , Internet/estadística & datos numéricos , Estructuras R-Loop , Humanos , Programas Informáticos
6.
Ann Nutr Metab ; 77(6): 344-349, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34564074

RESUMEN

AIMS/HYPOTHESIS: Beta-cell failure plays a fundamental role in type 2 diabetes mellitus (T2DM) development. It has been shown that the beta-cells are among the most sensitive to hypoxia. We aimed to analyze whether decrease in pancreatic perfusion relates to 1/decline in beta-cell function and 2/visceral fat accumulation in patients with T2DM. METHODS: Fifteen women with T2DM on metformin therapy alone and fifteen women of comparable age and BMI without prediabetes/diabetes were cross-sectionally examined: clinical and anthropometric examination, fast sampled intravenous glucose tolerance test (FSIVGTT), dynamic contrast-enhanced magnetic resonance imaging to assess pancreatic perfusion (area under the curve of postcontrast saturation, AUCTSIC), and visceral adiposity (VAT, calculated from transverse sections at the level L2-L5 vertebrae). RESULTS: Pancreatic blood perfusion (AUCTSIC) did not differ between groups (p = 0.273), but it negatively correlated with BMI (r = -0.434, p = 0.017), WHR (r = -0.411, p = 0.024), and VAT (r = -0.436, p = 0.016) in both groups. Moreover, AUCTSIC in the head of the pancreas negatively correlated with the level of fasting glycemia (r = -0.401, p = 0.028) and HOMA-IR (r = -0.376, p = 0.041). DISCUSSION/CONCLUSION: We showed that decreased pancreatic perfusion did not relate to beta-cell dysfunction in early stages of T2DM development, but it was related to VAT, insulin resistance, and higher fasting glycemia. Furthermore, lower pancreatic perfusion was related to VAT, insulin resistance, and higher fasting glycemia.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Glucemia , Índice de Masa Corporal , Femenino , Humanos , Insulina , Grasa Intraabdominal/diagnóstico por imagen , Grasa Intraabdominal/patología , Obesidad/complicaciones , Páncreas/patología , Perfusión
7.
Sensors (Basel) ; 19(16)2019 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-31398931

RESUMEN

Cardiovascular diseases are one of most frequent cause of morbidity and mortality in the world. There is an emerging need for integrated, non-invasive, and easy-to-use clinical tools to assess accurately cardiovascular system primarily in the preventative medicine. We present a novel design for a non-invasive pulse wave velocity (PWV) assessment method integrated in a single brachial blood pressure monitor allowing for up to 100 times more sensitive recording of the pressure pulsations based on a brachial occlusion-cuff (suprasystolic) principle. The monitor prototype with built-in proprietary method was validated with a gold standard reference technique SphygmoCor VX device. The blood pressure and PWV were assessed on twenty-five healthy individuals (9 women, age (37 ± 13) years) in a supine position at rest by a brachial cuff blood pressure monitor prototype, and immediately re-tested using a gold standard method. PWV using our BP monitor was (6.67 ± 0.96) m/s compared to PWV determined by SphygmoCor VX (6.15 ± 1.01) m/s. The correlation between methods using a Pearson's correlation coefficient was r = 0.88 (p < 0.001). The study demonstrates the feasibility of using a single brachial cuff build-in technique for the assessment of the arterial stiffness from a single ambulatory blood pressure assessment.

8.
Nat Commun ; 9(1): 4467, 2018 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-30367036

RESUMEN

Energetic ions represent an important tool for the creation of controlled structural defects in solid nanomaterials. However, the current preparative irradiation techniques in accelerators show significant limitations in scaling-up, because only very thin layers of nanoparticles can be efficiently and homogeneously irradiated. Here, we show an easily scalable method for rapid irradiation of nanomaterials by light ions formed homogeneously in situ by a nuclear reaction. The target nanoparticles are embedded in B2O3 and placed in a neutron flux. Neutrons captured by 10B generate an isotropic flux of energetic α particles and 7Li+ ions that uniformly irradiates the surrounding nanoparticles. We produced 70 g of fluorescent nanodiamonds in an approximately 30-minute irradiation session, as well as fluorescent silicon carbide nanoparticles. Our method thus increased current preparative yields by a factor of 102-103. We envision that our technique will increase the production of ion-irradiated nanoparticles, facilitating their use in various applications.

9.
Biomaterials ; 176: 106-121, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29879652

RESUMEN

The blocking of specific protein-protein interactions using nanoparticles is an emerging alternative to small molecule-based therapeutic interventions. However, the nanoparticles designed as "artificial proteins" generally require modification of their surface with (bio)organic molecules and/or polymers to ensure their selectivity and specificity of action. Here, we show that nanosized diamond crystals (nanodiamonds, NDs) without any synthetically installed (bio)organic interface enable the specific and efficient targeting of the family of extracellular signalling molecules known as fibroblast growth factors (FGFs). We found that low nanomolar solutions of detonation NDs with positive ζ-potential strongly associate with multiple FGF ligands present at sub-nanomolar concentrations and effectively neutralize the effects of FGF signalling in cells without interfering with other growth factor systems and serum proteins unrelated to FGFs. We identified an evolutionarily conserved FGF recognition motif, ∼17 amino acids long, that contributes to the selectivity of the ND-FGF interaction. In addition, we inserted this motif into a de novo constructed chimeric protein, which significantly improved its interaction with NDs. We demonstrated that the interaction of NDs, as purely inorganic nanoparticles, with proteins can mitigate pathological FGF signalling and promote the restoration of cartilage growth in a mouse limb explant model. Based on our observations, we foresee that NDs may potentially be applied as nanotherapeutics to neutralize disease-related activities of FGFs in vivo.


Asunto(s)
Factores de Crecimiento de Fibroblastos/metabolismo , Nanodiamantes/química , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo , Secuencias de Aminoácidos , Animales , Cartílago/fisiología , Línea Celular , Proliferación Celular , Supervivencia Celular , Embrión de Mamíferos , Humanos , Ligandos , Ratones , Unión Proteica , Transducción de Señal , Tibia/fisiología , Técnicas de Cultivo de Tejidos
10.
Biomed Tech (Berl) ; 61(6): 611-621, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26943590

RESUMEN

Systemic arterial blood pressure (BP) is one of the most important parameters of the cardiovascular system. An oscillometric NIBP monitor was specifically designed to measure oscillometric pulsations and mean arterial pressure (MAP) during inflation and deflation of the cuff. Nineteen healthy young (age 23.1±1.7 years; mean±SD) and 35 elderly (83.9±7.9 years; mean±SD) subjects were studied. Differential analysis of MAP during inflation and deflation show mean |ΔMAP|=2.9±2.6 mm Hg in the young group (mean±SD) and |ΔMAP|=6.3±5.2 mm Hg for seniors (mean±SD). There was a significant difference (p<0.05) in means of |ΔMAP| measured during cuff inflation and cuff deflation between both groups. In about 50% of elderly subjects |ΔMAP| was higher than 5 mm Hg. Potential clinical relevance of the method needs to be further evaluated.


Asunto(s)
Presión Arterial , Determinación de la Presión Sanguínea/métodos , Presión Sanguínea/fisiología , Adulto , Anciano , Brazo , Humanos
11.
Adv Healthc Mater ; 4(3): 460-8, 2015 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-25336437

RESUMEN

Targeted biocompatible nanostructures with controlled plasmonic and morphological parameters are promising materials for cancer treatment based on selective thermal ablation of cells. Here, core-shell plasmonic nanodiamonds consisting of a silica-encapsulated diamond nanocrystal coated in a gold shell are designed and synthesized. The architecture of particles is analyzed and confirmed in detail using electron tomography. The particles are biocompatibilized using a PEG polymer terminated with bioorthogonally reactive alkyne groups. Azide-modified transferrin is attached to these particles, and their high colloidal stability and successful targeting to cancer cells overexpressing the transferrin receptor are demonstrated. The particles are nontoxic to the cells and they are readily internalized upon binding to the transferrin receptor. The high plasmonic cross section of the particles in the near-infrared region is utilized to quantitatively ablate the cancer cells with a short, one-minute irradiation by a pulse 750-nm laser.


Asunto(s)
Técnicas de Ablación/métodos , Nanodiamantes/química , Materiales Biocompatibles/farmacocinética , Carbocianinas/química , Oro/química , Células HeLa/efectos de los fármacos , Humanos , Hipertermia Inducida/métodos , Terapia por Láser/métodos , Terapia Molecular Dirigida/métodos , Nanopartículas/química , Nanocáscaras/química , Polietilenglicoles/química , Receptores de Transferrina/metabolismo , Transferrina/química , Transferrina/farmacología
12.
Nanoscale ; 5(8): 3208-11, 2013 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-23314709

RESUMEN

A novel approach for preparation of ultra-bright fluorescent nanodiamonds (fNDs) was developed and the thermal and kinetic optimum of NV center formation was identified. Combined with a new oxidation method, this approach enabled preparation of particles that were roughly one order of magnitude brighter than particles prepared with commonly used procedures.


Asunto(s)
Fluorescencia , Colorantes Fluorescentes/síntesis química , Nanodiamantes/química , Colorantes Fluorescentes/efectos de la radiación , Nanodiamantes/efectos de la radiación , Tamaño de la Partícula , Protones , Coloración y Etiquetado/instrumentación , Coloración y Etiquetado/métodos
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