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1.
Nanomaterials (Basel) ; 13(20)2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37887903

RESUMEN

In this work, we employed a novel microwave-assisted synthesis method to produce nitrogen and boron co-doped carbon dots (B-N co-doped CDs). To achieve optimal synthesis, we conducted a comprehensive parameter modulation approach, combining various synthesis temperatures, times, and precursor concentrations, while keeping the power constant at 150 W and pH 5. Using maximum fluorescence emission as our response variable, the best conditions were identified as 120 °C, 3 min, and a precursor concentration of 1 mg/mL. Characterization using field emission scanning electron microscopy revealed these CDs to have a spherical morphology with an average size of 10.9 ± 3.38 nm. Further high-resolution transmission electron microscopy showed an interplanar distance of 0.23 nm, which is in line with prior findings of CDs that present a 0.21 nm distance corresponding to the (100) plane of graphite. Optical properties were ascertained through UV-vis absorption, identifying distinct π-π* and n-π* transitions. Fluorescence spectroscopy highlighted an emission peak at 375 nm when excited at 295 nm, achieving a quantum yield of 56.7%. Fourier-transform infrared spectroscopy and Raman spectroscopy analyses confirmed the boronic acid and amine groups' presence, underscoring the graphitic nature of the core and the co-doping of boron and nitrogen. These empirical observations were compared with theoretical investigations through simulated Raman spectra, proposing a potential structure for the CDs. X-ray photoelectron spectroscopy further endorsed the co-doping of nitrogen and boron, along with the detection of the specified functional groups. All these characteristics could lend this nanomaterial to different types of applications such as fluorescent probes for a broad range of analytes and for fluorescent cell imaging.

2.
Sensors (Basel) ; 23(10)2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37430547

RESUMEN

The use of enzyme-based biosensors for the detection and quantification of analytes of interest such as contaminants of emerging concern, including over-the-counter medication, provides an attractive alternative compared to more established techniques. However, their direct application to real environmental matrices is still under investigation due to the various drawbacks in their implementation. Here, we report the development of bioelectrodes using laccase enzymes immobilized onto carbon paper electrodes modified with nanostructured molybdenum disulfide (MoS2). The laccase enzymes were two isoforms (LacI and LacII) produced and purified from the fungus Pycnoporus sanguineus CS43 that is native to Mexico. A commercial purified enzyme from the fungus Trametes versicolor (TvL) was also evaluated to compare their performance. The developed bioelectrodes were used in the biosensing of acetaminophen, a drug widely used to relieve fever and pain, and of which there is recent concern about its effect on the environment after its final disposal. The use of MoS2 as a transducer modifier was evaluated, and it was found that the best detection was achieved using a concentration of 1 mg/mL. Moreover, it was found that the laccase with the best biosensing efficiency was LacII, which achieved an LOD of 0.2 µM and a sensitivity of 0.108 µA/µM cm2 in the buffer matrix. Moreover, the performance of the bioelectrodes in a composite groundwater sample from Northeast Mexico was analyzed, achieving an LOD of 0.5 µM and a sensitivity of 0.015 µA/µM cm2. The LOD values found are among the lowest reported for biosensors based on the use of oxidoreductase enzymes, while the sensitivity is the highest currently reported.


Asunto(s)
Acetaminofén , Agua Subterránea , Lacasa , Molibdeno , Trametes , Electrodos , Carbono
3.
Nanomaterials (Basel) ; 12(22)2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36432260

RESUMEN

Groundwater is one of the primary sources of water for both drinking and industrial use in northeastern Mexican territory, around 46% of the total, due to the lack of precipitation during the year and solar radiation index. The presence of arsenic in brackish soil and groundwater is a severe health issue, specifically in semi-arid and arid regions in the north of Mexico. Additionally, it represents the only source of drinking water in communities far from big cities, mainly due to the absence of hydric infrastructure. This work presents a new approach to treating polluted water with arsenic. The system based on activating jute fiber with nanoparticles of zero-valent iron immobilized over graphene oxide will allow nZVI particles to preserve their unique qualities for water sanitization. A dynamic flow test was designed to determine the effectivity of activated jute fibers as a water sanitation system. The results showed a reduction in the total arsenic content from 350 ppb to 34 ppb with a filtrate flow of 20 mL/min. The above represents 90% adsorption by the activated fiber. The analyzed sample corresponds to contaminated groundwater taken from Coahuila, Mexico. This sanitation system could be applied to low-income populations lacking robust infrastructure, such arsenic treatment plants.

4.
Membranes (Basel) ; 12(11)2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36422146

RESUMEN

The surface modification of materials obtained from natural polymers, such as silk fibroin with metal nanoparticles that exhibit intrinsic electrical characteristics, allows the obtaining of biocomposite materials capable of favoring the propagation and conduction of electrical impulses, acting as communicating structures in electrically isolated areas. On that basis, this investigation determined the electrochemical and electroconductive behavior through electrochemical impedance spectroscopy of a silk fibroin electrospun membrane from silk fibrous waste functionalized with gold or silver nanoparticles synthetized by green chemical reduction methodologies. Based on the results obtained, we found that silk fibroin from silk fibrous waste (SFw) favored the formation of gold (AuNPs-SFw) and silver (AgNPs-SFw) nanoparticles, acting as a reducing agent and surfactant, forming a micellar structure around the individual nanoparticle. Moreover, different electrospinning conditions influenced the morphological properties of the fibers, in the presence or absence of beads and the amount of sample collected. Furthermore, treated SFw electrospun membranes, functionalized with AuNPs-SFw or AgNPS-SFw, allowed the conduction of electrical stimuli, acting as stimulators and modulators of electric current.

5.
J Clin Med ; 11(15)2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35956206

RESUMEN

Introduction: Heart failure is an extremely prevalent disease in the elderly population of the world. Most patients present signs and symptoms of decompensation of the disease due to worsening congestion. This congestion has been clinically assessed through clinical signs and symptoms and complementary imaging tests, such as chest radiography. Recently, pulmonary and inferior vena cava ultrasound has been shown to be useful in assessing congestion but its prognostic significance in elderly patients has been less well evaluated. Objectives: This study aims to compare the clinical and radiological characteristics and predictive values for mortality in patients admitted for heart failure through the determination of B lines by lung ultrasound and the degree of collapsibility of the inferior vena cava (IVC). Secondarily, the study aims to assess the prediction of 30-day mortality based on the diameter of the IVC by means of the ROC curve. Methods: This is an observational cohort study based on data collected in the PROFUND-IC study, a nationwide multicentric registry of patients admitted with decompensated heart failure. Data were collected from these patients between October 2020 and April 2022. Results: A total of 482 patients were entered into the PROFUND-IC registry between October 2020 and April 2022. Bedside clinical ultrasound was performed during admission in 301 patients (64.3%). The number of patients with more than 6 B-lines on lung ultrasound amounted to 194 (66%). Statistically significant differences in 30-day mortality (22.1% vs. 9.2%; p = 0.01) were found in these patients. The sum of patients with IVC collapsibility of less than 50% amounted to 195 (67%). Regarding prognostic value, collapsibility data were significant for the number of admissions in the last year (12.5% vs. 5.5%; p = 0.04), in-hospital mortality (10.1% vs. 3.3%, p = 0.04) and 30-day mortality (22.6% vs. 8.1%; p < 0.01), but not for readmissions. Regarding the prognostic value of IVC diameter for 30-day mortality, the area under the ROC curve (AUC) was 0.73, with a p < 0.01. The curve cut-off point with the highest sensitivity (70%) and specificity (70.3%) was for an IVC value of 22.5 mm. In the logistic regression analysis, we observed that the variable most associated with patient survival at 30 days was the presence of a collapsible inferior vena cava, with more than 50% OR 0.359 (CI 0.139−0.926; p = 0.034). Conclusions: The subgroups of patients analyzed with more than six B lines per field and IVC collapsibility less than or equal to 50%, as measured by clinical ultrasound, had higher 30-day mortality rates than patients who did not fall into these subgroups. IVC diameter may be a good independent predictor of 30-day mortality in patients with decompensated heart failure. Comparing both ultrasound variables, it seems that in our population, the assessment of the inferior vena cava may be more associated with short-term prognosis than the pulmonary congestion variables assessed by B lines.

6.
Korean J Intern Med ; 37(1): 37-47, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34482681

RESUMEN

The incidence and prevalence of heart failure (HF) is increasing worldwide, leading to high morbidity and mortality. The global management of HF involves lifestyle changes in addition to pharmacological treatments. Changes include exercise and dietary recommendations, mainly salt and fluid restriction, but without any clear evidence. We conducted a systematic review to analyse the degree of evidence for these dietary recommendations in HF. Only randomized controlled trials (RCT), and observational studies in humans were selected. Studies were considered eligible if they included participants with HF and sodium and/or fluid restriction. Publications in languages other than English or Spanish were excluded. We included 15 studies related to sodium or fluid restriction. Nine RCT and six observational studies showed some improvements in symptoms and quality of life and a degree of reduction in new hospitalizations, but the results are based on limited population groups, applying different methodologies, and with different restriction goals. We found a lack of clear evidence of the benefits of sodium/fluid restriction in chronic HF. The evidence is limited to few studies with conflicting results. Randomized clinical trials are needed to fill this gap in our knowledge.


Asunto(s)
Insuficiencia Cardíaca , Enfermedad Crónica , Conducta Alimentaria , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/terapia , Hospitalización , Humanos , Sodio
7.
Polymers (Basel) ; 13(24)2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34960871

RESUMEN

Tissue engineering has focused on the development of biomaterials that emulate the native extracellular matrix. Therefore, the purpose of this research was oriented to the development of nanofibrillar bilayer membranes composed of polycaprolactone with low and medium molecular weight chitosan, evaluating their physicochemical and biological properties. Two-bilayer membranes were developed by an electrospinning technique considering the effect of chitosan molecular weight and parameter changes in the technique. Subsequently, the membranes were evaluated by scanning electron microscopy, Fourier transform spectroscopy, stress tests, permeability, contact angle, hemolysis evaluation, and an MTT test. From the results, it was found that changes in the electrospinning parameters and the molecular weight of chitosan influence the formation, fiber orientation, and nanoarchitecture of the membranes. Likewise, it was evidenced that a higher molecular weight of chitosan in the bilayer membranes increases the stiffness and favors polar anchor points. This increased Young's modulus, wettability, and permeability, which, in turn, influenced the reduction in the percentage of cell viability and hemolysis. It is concluded that the development of biomimetic bilayer nanofibrillar membranes modulate the physicochemical properties and improve the hemolytic behavior so they can be used as a hemocompatible biomaterial.

8.
Medicina (Kaunas) ; 57(11)2021 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-34833368

RESUMEN

Background and Objectives: The prevalence and incidence of heart failure (HF) have been increasing in recent years as the population ages. These patients show a distinct profile of comorbidity, which makes their care more complex. In recent years, the PROFUND index, a specific tool for estimating the mortality rate at one year in pluripathology patients, has been developed. The aim of this study was to evaluate the prognostic value of the PROFUND index and of in-hospital and 30-day mortality after discharge of patients admitted for acute heart failure (AHF). Materials and Methods: A prospective multicenter longitudinal study was performed that included patients admitted with AHF and ≥2 comorbid conditions. Clinical, analytical, and prognostic variables were collected. The PROFUND index was collected in all patients and rates of in-hospital and 30-day mortality after discharge were analyzed. A bivariate analysis was performed with quantitative variables between patients who died and those who survived at the 30-day follow-up. A logistic regression analysis was performed with the variables that obtained statistical significance in the bivariate analysis between deceased and surviving subjects. Results: A total of 128 patients were included. Mean age was 80.5 +/- 9.98 years, and women represented 51.6%. The mean PROFUND index was 5.26 +/- 4.5. The mortality rate was 8.6% in-hospital and 20.3% at 30 days. Preserved left ventricular ejection fraction was found in 60.9%. In the sample studied, there were patients with a PROFUND score < 7 predominated (89 patients (70%) versus 39 patients (31%) with a PROFUND score ≥ 7). Thirteen patients (15%) with a PROFUND score < 7 died versus the 13 (33%) with a PROFUND score ≥ 7, p = 0.03. Twelve patients (15%) with a PROFUND score < 7 required readmission versus 12 patients (35%) with a PROFUND score ≥ 7, p = 0.02. The ROC curve of the PROFUND index for in-hospital mortality and 30-day follow-up in patients with AHF showed AUC 0.63, CI: 95% (0.508-0.764), p <0.033. Conclusions: The PROFUND index is a clinical tool that may be useful for predicting short-term mortality in elderly patients with AHF. Further studies with larger simple sizes are required to validate these results.


Asunto(s)
Insuficiencia Cardíaca , Función Ventricular Izquierda , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Estudios Longitudinales , Pronóstico , Estudios Prospectivos , Volumen Sistólico
9.
Med Clin (Barc) ; 156(12): 622-624, 2021 06 25.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33810871

RESUMEN

OBJECTIVES: To analyze the prevalence of May-Thurner syndrome (MTS) among patients with deep vein thrombosis (DVT) of left lower limb (LLL), and outcomes after long-term follow-up. METHOD: Retrospective observational study that included patients older than 18 diagnosed with acute DVT and MTS. RESULTS: Among 760 patients diagnosed with DVT in the LLL, 8 patients were diagnosed with MTS (1.05%), with a mean age of 39 years. All patients received long-term anticoagulation, with a mean of 31.9 (±25.2) months. Invasive treatment with pharmaco-mechanical thrombectomy was performed in 5 patients (62.5%). During follow-up (mean of 32.4 months), 25% of patients suffered DVT recurrence. Only 1 case presented major bleeding, and no deaths were registered. CONCLUSIONS: May-Thurner syndrome constitutes a permanent and underdiagnosed risk factor for the development of DVT of LLL. Our findings suggest that long-term anticoagulation therapy might be considered in selected cases.


Asunto(s)
Síndrome de May-Thurner , Trombosis de la Vena , Adulto , Humanos , Extremidad Inferior , Síndrome de May-Thurner/complicaciones , Síndrome de May-Thurner/diagnóstico , Síndrome de May-Thurner/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , Trombosis de la Vena/epidemiología , Trombosis de la Vena/etiología
10.
Polymers (Basel) ; 12(12)2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33265903

RESUMEN

The influence of the lateral size and the content of graphene oxide (GO) flakes in specific oxygenate functional groups on the anti-biofouling properties and performance of thin-film composite membrane (TFC) was studied. Three different multidimensional GO samples were prepared with small (500-1200 nm), medium (1200-2300 nm), and large (2300-3600 nm) size distribution, and with different degrees of oxidation (GO3 > GO2 > GO1), varying the concentration of the hydrogen peroxide amount during GO synthesis. GO1 sheets' length have a heterogeneous size distribution containing all size groups, whilst GO2 is contained in a medium-size group, and GO3 is totally contained within a small-size group. Moreover, GO oxygenate groups were controlled. GO2 and GO3 have hydroxyl and epoxy groups at the basal plane of their sheets. Meanwhile, GO1 presented only hydroxyl groups. GO sheets were incorporated into the polyamide (PA) layer of the TFC membrane during the interfacial polymerization reaction. The incorporation of GO1 produced a modified membrane with excellent bactericidal properties and anti-adhesion capacity, as well as superior desalination performance with high water flow (133% as compared with the unmodified membrane). For GO2 and GO3, despite the significant anti-biofouling effect, a detrimental impact on desalination performance was observed. The high content of large sheets in GO2 and small sheet stacking in GO3 produced an unfavorable impact on the water flow. Therefore, the synergistic effect due to the presence of large- and small-sized GO sheets and high content of OH-functional groups (GO1) made it possible to balance the performance of the membrane.

11.
Thromb Res ; 196: 305-307, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32977127

RESUMEN

INTRODUCTION: Inferior vena cava agenesis (IVCA) is a rare and underdiagnosed congenital anomaly that predisposes to deep vein thrombosis (DVT). Optimal duration of anticoagulant treatment in these patients is not well established. METHOD: Observational retrospective study that included all consecutive patients older than 18 diagnosed with IVCA and DVT. Data including demographics, initial clinical presentation, modality of diagnosis, treatment and outcomes were obtained. RESULTS: In patients with IVCA and DVT (n = 9), mean age was 42 and 66% were males. Five (55,5%) patients had bilateral DVT and the most frequent location was ilio-femoral. Only one patient had concomitant pulmonary embolism (PE). During follow-up (mean of 77.8 months), anticoagulation was withdrawn in 2 patients and both developed recurrence of DVT (22.2%, CI 95% 2.8-60.0). One minor bleeding (11.1%, CI 95% 0.3-48.3), five post-thrombotic syndrome (55.6%, CI 95% 21.2-86.3) and no deaths were registered. CONCLUSION: In patients with DVT and IVCA, post-thrombotic syndrome was developed in approximately half of the patients. No major bleeding events were recorded during long-term anticoagulant therapy and recurrences occurred only in patients who had anticoagulation withdrawn. These data suggest that extended anticoagulant therapy might be considered in these patients.


Asunto(s)
Embolia Pulmonar , Trombosis de la Vena , Adulto , Anciano , Anticoagulantes/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Vena Cava Inferior , Trombosis de la Vena/tratamiento farmacológico
12.
ACS Omega ; 5(32): 20335-20342, 2020 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-32832786

RESUMEN

In this work, copper selenide (Cu3Se2 umangite phase) was synthesized by two routes, using a chemical reaction and the hydrothermal method to obtain CuSe-A and CuSe-H, respectively. The synthesis of Cu3Se2 consisted of a three-step process: in the first step, copper(I) oxide hexapods (Cu2O) were obtained as the copper reservoir; in the second step, selenium ions were obtained from the reduction of selenium powder; and in the third step involves mixing two precursors following the two synthesis routes mentioned before. Analysis of X-ray diffraction and X-ray photoelectron spectroscopy showed the formation of the Cu3Se2 phase by both synthesis routes. On the other hand, using the scanning electron microscopy (SEM) technique, it is observed that the Cu3Se2 sample (CuSe-A) is obtained by exchanging in solution with agitation and that the copper selenium phase grows only on the surface of the hexapods. Meanwhile, the hydrothermal route promotes a total conversion of copper(I) oxide hexapods to the copper selenide phase (CuSe-H). The resulting materials were tested as photocatalytic materials to remove methylene blue dye in water under sunlight irradiation. Cu3Se2 (CuSe-H) obtained by the hydrothermal route exhibited a higher efficiency of photodegradation of dye, reaching a removal percentage of 92% after 4 h under sunlight.

14.
Biomed Opt Express ; 11(1): 388-405, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32010523

RESUMEN

Intrinsic radiosensitivity is a biological parameter known to influence the response to radiation therapy in cancer treatment. In this study, Raman spectroscopy and surface enhanced Raman spectroscopy (SERS) were successfully used in conjunction with principal component analysis (PCA) to discriminate between radioresistant (LY-R) and radiosensitive (LY-S) murine lymphoma sublines (L5178Y). PCA results for normal Raman analysis showed a differentiation between the radioresistant and radiosensitive cell lines based on their specific spectral fingerprint. In the case of SERS with gold nanoparticles (AuNPs), greater spectral enhancements were observed in the radioresistant subline in comparison to its radiosensitive counterpart, suggesting that each subline displays different interaction with AuNPs. Our results indicate that spectroscopic and chemometric techniques could be used as complementary tools for the prediction of intrinsic radiosensitivity of lymphoma samples.

16.
Kidney Blood Press Res ; 44(6): 1432-1440, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31683270

RESUMEN

BACKGROUND: There is limited evidence on the etiology and outcomes of renal infarction. A provoking factor is identified only in one- to two-thirds of patients. METHODS: This is a retrospective observational study. The clinical characteristics and outcomes of patients with acute renal infarction were studied; the sample was divided into two groups according to the presence of at least one provoking factor at the time of diagnosis (atrial fibrillation, flutter, major thrombophilia, or renal artery malformations). RESULTS: The study comprised 59 patients with a mean age of 63 (±16.7) years and a follow-up period of 3.1 (±2.8) years. An identifiable provoking factor was found for 59.3% of the renal infarctions at the time of diagnosis, and atrial fibrillation was the most frequent one (in 49.2% of all patients). Renal impairment was found in 49.2% of the patients at diagnosis and in 50.8% of the patients 6 months after the event (p = 0.525). When compared with the idiopathic group, the patients with provoked infarction were older (69.8 vs. 57.9 years, p = 0.014) and had a higher rate of recurrence of arterial thrombosis during follow-up (18.8 vs. 0%, p = 0.028), but there were no differences in the rest of the baseline characteristics or in mortality rates. Six patients (10.2%) in the idiopathic group were diagnosed with atrial fibrillation during follow-up. CONCLUSIONS: Atrial fibrillation, both at diagnosis and at follow-up, is the most common identifiable cause of renal infarction; however, a significant number of patients are idiopathic, and these are younger, but they have a similar burden of cardiovascular disease and a lower risk of arterial recurrence.


Asunto(s)
Enfermedades Cardiovasculares/complicaciones , Infarto/etiología , Riñón/irrigación sanguínea , Centros de Atención Terciaria , Factores de Edad , Anciano , Fibrilación Atrial/complicaciones , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Trombosis/complicaciones
18.
Intractable Rare Dis Res ; 8(1): 60-66, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30881861

RESUMEN

Behçet's Disease (BD) is a rare, chronic and recurrent inflammatory multisystemic condition of unknown origin that can affect any tissue. The vascular system is involved in 5-40% of cases of BD, including venous and arterial beds and it has a relapsing course. Budd-Chiari syndrome (BCS) is a rare complication of BD with a frequency of < 5% among patients with vascular involvement and is more frequent in men (89.5%). Two clinical presentation groups of BCS related to BD have been described: the "symptomatic" form and the "silent" form. We present a case of BD in a young woman presented as symptomatic severe BCS with rapid progression of coagulopathy reaching a spontaneous INR of 1.74 and increased ascites by ultrasound control. BD was confirmed through clinical history. The patient was treated with a high-dose pulse of corticosteroids and cyclophosphamide with a strikingly favorable response in the first forty-eight hours. Although several studies have demonstrated a survival improvement with the use of transjugular intrahepatic portosystemic shunt in patients with severe BCS, it was discarded due to the lack of evidence of this procedure in patients with BD and the fact that it could trigger a vascular pathergy phenomenon. Vascular BD should be suspected in recurrent venous and/or arterial thrombosis since it is associated with high morbidity and mortality. Immunosuppressive treatment is critical for the management of vascular involvement in BD. However, the role of anticoagulation is debatable. We suggest an algorithm for the management of BCS associated with BD.

19.
Microsc Res Tech ; 82(5): 507-516, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30597696

RESUMEN

Spruce wood (picea abis) has been widely used as structural element, from buildings to musical instruments, due to its outstanding mechanical performances. The main stem transverse section exhibits growth rings formed by periodic fringes patterns, which are constituted by lamellae-tracheid arrangements. In order to improve the understanding of each wood microstructure role, the morphology and crystallinity of earlywood and latewood fibers were examined mainly using scanning electron microscopy, atomic force microscopy, and X-ray difracction. Moreover, measurements of effective elastic modulus and hardness were obtained by nanoindentation tests using a Berkovich indenter in order to confirmed increase in compactness of the wood microstructures. The results indicate that variations in mechanical properties values can be associated with well defined microstructural performances for each characteristic fiber type, where those that belong to latewood fiber showed the most improved behaviors. A finite element simulation of a lamellar-tracheids arrangement was carried out in order to clarify its stiffness and elastic deformation capabilities, as relevant factors contributing to the successful adaptation of picea abis colonies to harsh conditions habitats as well as for its construction applications of string instruments.


Asunto(s)
Microscopía de Fuerza Atómica , Picea/ultraestructura , Madera/ultraestructura , Fenómenos Biomecánicos , Análisis de Elementos Finitos , Microscopía Electrónica de Rastreo , Difracción de Rayos X
20.
Clin Case Rep ; 5(12): 1919-1922, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29225825

RESUMEN

Leptomeningeal involvement of CLL is usually underdiagnosed as neurological symptoms are unspecific. It is important to carefully evaluate neurological status in these patients and consider this entity between the differential diagnosis of a neurological deterioration as adequate treatment improves the prognosis. Imaging techniques, analyses of cerebrospinal fluid, and brain biopsy are useful to establish a definitive diagnosis.

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