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1.
Phys Chem Chem Phys ; 26(12): 9149-9154, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-37869980

RESUMEN

2D materials present an interesting platform for device designs. However, oxidation can drastically change the system's properties, which need to be accounted for. Through ab initio calculations, we investigated freestanding and SiC-supported As, Sb, and Bi mono-elemental layers. The oxidation process occurs through an O2 spin-state transition, accounted for within the Landau-Zener transition. Additionally, we have investigated the oxidation barriers and the role of spin-orbit coupling. Our calculations pointed out that the presence of SiC substrate reduces the oxidation time scale compared to a freestanding monolayer. We have extracted the energy barrier transition, compatible with our spin-transition analysis. Besides, spin-orbit coupling is relevant to the oxidation mechanisms and alters time scales. The energy barriers decrease as the pnictogen changes from As to Sb to Bi for the freestanding systems, while for SiC-supported, they increase across the pnictogen family. Our computed energy barriers confirm the enhanced robustness against oxidation for the SiC-supported systems.

2.
Phys Chem Chem Phys ; 25(2): 1161-1168, 2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36519443

RESUMEN

The development of electronic devices based on the functionalization of (nano)cellulose platforms relies upon an atomistic understanding of the structural and electronic properties of a combined system, cellulose/functional element. In this work, we present a theoretical study of the nanocellulose/graphene interfaces (nCL/G) based on first-principles calculations. We find that the binding energies of both hydrophobic/G (nCLphob/G) and hydrophilic/G (nCLphil/G) interfaces are primarily dictated by the van der Waals interactions, and are comparable with those of their 2D interface counterparts. We verify that the energetic preference of nCLphob/G has been reinforced by the inclusion of an aqueous medium via an implicit solvation model. Further structural characterization was carried out using a set of simulations of the carbon K-edge X-ray absorption spectra to identify and distinguish the key absorption features of the nCLphob/G and nCLphil/G interfaces. The electronic structure calculations reveal that the linear energy bands of graphene lie in the band gap of the nCL sheet, while depletion/accumulation charge density regions are observed. We show that external agents, i.e., electric field and mechanical strain, allow for tunability of the Dirac cone and charge density at the interface. The control/maintenance of the Dirac cone states in nCL/G is an important feature for the development of electronic devices based on cellulosic platforms.


Asunto(s)
Grafito , Carbono , Celulosa , Electricidad , Electrónica
3.
Childs Nerv Syst ; 38(1): 25-32, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34562131

RESUMEN

BACKGROUND AND AIM: Shunt dysfunction is a common event, especially in children who have this intervention performed early in life. The consequences of chronic shunt overdrainage can be multiple since the cerebral hydrodynamics is altered. A thrombotic event with consequent symptoms of intracranial hypertension is discussed in this article. MATERIAL AND METHODS: We performed a detailed review of cerebral hydrodynamics and intracranial pressure compensation mechanisms and how this can alter cerebral venous circulation. Next, we report the case of a 4-year-old child with such a clinical presentation that was conducted by our team. RESULTS: A child with a history of hydrocephalus treated with a ventriculo-peritoneal (VP) shunt in his early childhood presented with symptoms of intracranial hypertension, initial computed tomography (CT) demonstrating reduced-sized ventricles. Complementary investigation showed bilateral papilledema, cranial suture closure, changes compatible with Chiari type I, and venous sinus thrombosis (transverse and sigmoid, bilaterally). The case was managed conservatively with full anticoagulation with enoxaparin. Four months after the onset of symptoms, there was an improvement in the clinical and imaging status. CONCLUSION: A condition of severe headache in a patient with an apparently functioning shunt and small ventricles on initial CT should open up a range of diagnostic possibilities, with pseudotumor cerebri syndrome and cerebral venous sinus thrombosis being suggested. The therapeutic approach in these cases must be individualized.


Asunto(s)
Hipertensión Intracraneal , Papiledema , Seudotumor Cerebral , Trombosis de los Senos Intracraneales , Preescolar , Senos Craneales/diagnóstico por imagen , Senos Craneales/patología , Humanos , Hipertensión Intracraneal/complicaciones , Papiledema/etiología , Seudotumor Cerebral/cirugía , Trombosis de los Senos Intracraneales/complicaciones , Trombosis de los Senos Intracraneales/etiología
4.
Phys Chem Chem Phys ; 23(19): 11501-11506, 2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-33960330

RESUMEN

Recently cycloarene has been experimentally obtained in a self-assembled structure, forming graphene-like monoatomic layered systems. Here, we established bandgap engineering/prediction in cycloarene assemblies within a combination of density functional theory and tight-binding Hamiltonians. Our results show that the inter-molecule bond density rules the bandgap. The increase in such bond density increases the valence/conduction bandwidth decreasing the energy gap linearly. We derived an effective model that allows the interpretation of the arising energy gap for general particle-hole symmetric molecular arrangements based on inter-molecular bond strength.

5.
Eur J Neurol ; 27(10): 2072-2078, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32441838

RESUMEN

BACKGROUND AND PURPOSE: Neurological manifestations have been identified in the context of autoimmune hepatitis (AIH). Previous case reports highlighted the association between AIH and sensory neuronopathy (SN). Despite that, little is known about the frequency of AIH-related SN and its clinical/neurophysiological profile. Moreover, it is not clear whether SN is an AIH-specific manifestation or related to chronic liver damage. METHODS: Seventy consecutive AIH patients were enrolled and their characteristics were compared with 52 consecutive patients with chronic active hepatitis B. All subjects underwent clinical and neurophysiological evaluation. Further comparisons were performed between AIH SN and AIH non-SN patients. RESULTS: Mean ages and male:female proportions in the AIH and chronic active hepatitis B groups were 42.2 ± 16.3/51.7 ± 13.6 years and 14:56/29:23, respectively. The frequencies of carpal tunnel syndrome, radiculopathy and polyneuropathy were similar between groups. In contrast, SN was identified only in AIH patients (5/70 vs. 0/52, P = 0.04); the overall prevalence of AIH-related SN was 7% with an average profile of a woman in her 40s with asymmetric onset of sensory deficits that chronically evolved to disabling proprioceptive ataxia associated with marked dysautonomia. Neurological disability and hepatocellular damage did not follow in parallel. Anti-fibroblast growth factor receptor type 3 antibodies were found in 3/5 (60%) of the patients with AIH-related SN. Clinical or demographic predictors of SN in the context of AIH could not be identified. CONCLUSION: Sensory neuronopathy, but not other peripheral nervous system diseases, is a specific AIH neurological manifestation. It is often disabling and, in contrast to hepatocellular injury, does not respond to immunosuppression.


Asunto(s)
Hepatitis Autoinmune , Hepatopatías , Enfermedades del Sistema Nervioso Periférico , Adulto , Anciano , Femenino , Hepatitis Autoinmune/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso Periférico/epidemiología , Enfermedades del Sistema Nervioso Periférico/etiología
6.
Phys Chem Chem Phys ; 22(37): 21504-21511, 2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-32955064

RESUMEN

It has recently been demonstrated that N-heterocyclic carbenes (NHCs) form self-assembled monolayers (SAMs) on metal surfaces. Consequently, it is important to both characterize and understand their binding modes to fully exploit NHCs in functional surface systems. To assist with this effort, we have performed first-principles total energy calculations for NHCs on Au(111) and simulations of X-ray absorption near edge structure (XANES). The NHCs we have considered are N,N-dimethyl-, N,N-diethyl-, N,N-diisopropylbenzimidazolylidene (BNHCX, with X = Me, Et, and iPr, respectively) and the bis-BNHCX-Au complexes derived from these molecules. We present a comprehensive analysis of the energetic stability of both the BNHCX and the complexes on Au(111) and, for the former, examine the role of the wing group in determining the attachment geometry. Further structural characterization is performed by calculating the nitrogen K-edge X-ray absorption spectra. Our simulated XANES results give insight into (i) the relationship between the BNHCX/Au geometry and the N(1s) → π*/σ*, pre-edge/near-edge, absorption intensities, and (ii) the contributions of the molecular deformation and molecule-surface electronic interaction to the XANES spectrum. These simulated spectra work not only as a map to the BNHCX conformation, but also, combined with electronic structure calculations, provide a clear understanding of recent experimental XANES findings on BNHCX/Au.

7.
Nano Lett ; 19(9): 6564-6568, 2019 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-31424949

RESUMEN

Recently, orbital-textures have been found in Rashba and topological insulator (TI) surface states as a result of the spin-orbit coupling (SOC). Here, we predict a px/py orbital texture, in linear dispersive Dirac bands, arising at the K/K' points of χ-h0 borophene chiral monolayer. Combining "first-principles" calculations with effective Hamiltonians, we show that the orbital pseudospin has its direction locked with the momentum in a similar way as TIs' spin-textures. Additionally, considering a layer pseudospin degree of freedom, this lattice allows stackings of layers with equivalent or opposite chiralities. In turn, we show a control of the orbital textures and layer localization through the designed stacking and external electric field. For instance, for the opposite chirality stacking, the electric field allows for an on/off switch of the orbital-textured Dirac cone.

8.
Med Oral Patol Oral Cir Bucal ; 25(4): e541-e548, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32520920

RESUMEN

BACKGROUND: Oral rehabilitation of atrophic maxillae features high complexity, for which there are several therapeutic modalities reported on scientific literature. Zygomatic implant placement is a viable option that features low morbidity and allows immediate prosthetic loading. The purpose of the present study was to determine the methodological quality of systematic reviews that assessed the effectiveness of zygomatic implants placed in atrophic maxillae. MATERIAL AND METHODS: Searches were conducted on Medline via Pubmed, LILACS, Dare Cochrane, Scopus, and Sigle via Open Grey up to June 2019. RESULTS: Seven systematic reviews were eligible for Overview and comprised a total of 2313 patients, 4812 zygomatic implants, and a 96,72% success rate. Common surgical complications, in decreasing order, were: maxillary sinusitis, peri-implant mucositis, prosthetic fracture, and infections. Methodological quality was assessed using the AMSTAR 2 tool, which revealed that six systematic reviews showed critically low methodological quality and one review was assessed as of low methodological quality. CONCLUSIONS: Zygomatic implants seem to be an adequate option for atrophic maxilla rehabilitation, however, new studies with a higher methodological rigor are needed to provide more reliable results to professionals and patients undergoing this modality of oral rehabilitation.


Asunto(s)
Implantes Dentales , Arcada Edéntula/cirugía , Sinusitis Maxilar , Implantación Dental Endoósea , Prótesis Dental de Soporte Implantado , Estudios de Seguimiento , Humanos , Maxilar/cirugía , Revisiones Sistemáticas como Asunto
9.
Eur J Neurol ; 26(3): 483-489, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30326180

RESUMEN

BACKGROUND AND PURPOSE: Friedreich's ataxia (FRDA) is the most common autosomal-recessive ataxia worldwide. It is characterized by early onset, sensory abnormalities and slowly progressive ataxia. All magnetic resonance imaging (MRI)-based studies have focused on the evaluation of adult patients. Therefore, we designed a cross-sectional multimodal MRI-based study to investigate the anatomical substrates involved in the early stages of FRDA. METHODS: We enrolled 37 patients (12 children) and 38 controls. All subjects underwent MRI in a 3T device to assess gray and white matter. We used measures from FreeSurfer and CERES to evaluate the cerebral and cerebellar cortices. The T1 multiatlas assessed deep gray matter. The diffusion tensor imaging multiatlas was used to investigate microstructural abnormalities in brain white matter and SpineSeg was used to assess the cervical spinal cord. All analyses were corrected for multiple comparisons. RESULTS: Comparison with age-matched controls showed that pediatric patients have spinal cord, inferior cerebellar peduncle and red nucleus damage. In contrast, adult patients showed more widespread white matter damage than pediatric patients. With regard to gray matter, we found cortical thinning at the left central sulcus and volumetric reduction in the thalami and hippocampi only in adult patients. Finally, values of fractional anisotropy in adult patients and radial diffusivity in pediatric patients from the inferior cerebellar peduncle correlated with disease duration and ataxia severity, respectively. CONCLUSIONS: Structural damage in FRDA begins in the spinal cord and inferior cerebellar peduncle as well as the red nucleus, and progresses to cerebral areas in adulthood. These results shed some light on the early stages of FRDA and highlight potential neuroimaging markers for therapeutic trials.


Asunto(s)
Ataxia de Friedreich , Sustancia Gris , Sustancia Blanca , Adolescente , Adulto , Anciano , Niño , Estudios Transversales , Femenino , Ataxia de Friedreich/diagnóstico por imagen , Ataxia de Friedreich/patología , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Adulto Joven
10.
Phys Chem Chem Phys ; 21(40): 22344-22350, 2019 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-31576867

RESUMEN

Materials with properties designed on-demand arise in a synergy between theoretical and experimental approaches. Here, we explore a set of Archimedean lattices, providing a guide to their electronic properties and topological phases. Within these lattices, a rich electronic structure emerges forming type-I and II Dirac fermions, topological flat bands and high-degeneracy points with linear and flat dispersions. Employing a tight-binding model with spin-orbit coupling, we characterize quantum spin Hall (QSH) phases in all Archimedean lattices. Our discussions are validated within density functional theory calculations, where we show the characteristic bands of the studied lattices arising in 2D carbon allotropes.

11.
J Chem Phys ; 150(23): 234701, 2019 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-31228898

RESUMEN

We investigate the layer localization control of two-dimensional states in multilayer metal-organic frameworks (MOFs). For finite stackings of (NiC4S4)3 MOFs, the weak van der Waals coupling between adjacent layers leads to a Fermi level dependent distribution of the electronic states in the monolayers. Such distribution is reflected in the topological edge states of multilayer nanoribbons. Moreover, by applying an external electric field parallel to the stacking direction, the spatial localization of the electronic states can be controlled for a chosen Fermi energy. This localization behavior is studied comparing density functional theory calculations with a kagome lattice tight-binding model. Furthermore, for infinite stacked nanoribbons, a new V-gutter Dirac state is found in the side surfaces, which allows anisotropic current control by tuning the Fermi energy. Our results can be immediately extended to other kagome MOFs with eclipsed stackings, introducing a new degree of freedom (layer localization) to materials design.

12.
Med Oral Patol Oral Cir Bucal ; 24(4): e483-e490, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31232387

RESUMEN

BACKGROUND: Since implant placement on diabetic patients still is a controversial topic and systematic reviews are at the top of scientific evidence hierarchy, a thorough assessment of the methodological quality of these reviews must be performed to inform clinicians if their conclusions and recommendations can be followed on clinical practice. An overview of systematic reviews was performed with the purpose to assess the methodological quality of systematic reviews regarding dental implant placement on diabetic patients. In addition, we presented a synthesis of clinical outcomes about the focused theme. MATERIAL AND METHODS: An online search was performed on MEDLINE via PubMed, EMBASE, DARE-Cochrane, Scopus, Web of Science, LILACS, and SIGLE via Open Grey. Searches were conducted from database inception to May 2018. Systematic review articles with or without meta-analysis about the placement of dental implants on diabetic patients were included. Exclusion criteria were: articles whose primary outcome was not the survival/success rate of dental implants on diabetic patients; studies that do not relate the survival/success rate of dental implants with diabetes; duplicated papers. Methodological quality assessment was performed with AMSTAR. A descriptive synthesis of clinical outcomes was performed. RESULTS: We identified 1.661 initial hits and eight articles were selected for overview (kappa=0.83; strong agreement). Six studies presented moderate methodological quality and two showed high methodological quality. Implant survival rate ranged from 31.8% to 100% and data from four meta-analysis showed that diabetes does not affect implant survival rate. On the other hand, data from two meta-analysis for marginal bone loss showed that diabetes statistically affects this outcome. CONCLUSIONS: Two of the eight included studies presented high methodological quality and their meta-analysis showed that implant placement on diabetic patients does not affect implant survival rate and statistically affects marginal bone loss. However, clinicians must be aware that marginal bone loss values were not clinically relevant and may not be safe to follow the conclusions and recommendations of these studies.


Asunto(s)
Implantes Dentales , Diabetes Mellitus , Fracaso de la Restauración Dental , Humanos
13.
Med Oral Patol Oral Cir Bucal ; 24(4): e518-e528, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31232386

RESUMEN

BACKGROUND: Alveolar infection is known as a risk factor for implant failure. Current meta-analysis on the theme could not prove statistically that immediate dental implants placed into infected sites have a higher risk of failure than immediate dental implants placed into non-infected sites. The purpose of this meta-analysis was to determine the effectiveness of immediate dental implants placed into infected versus non-infected sites. MATERIAL AND METHODS: Seven databases were sought by two reviewers. Randomized or non-randomized clinical trials that compared the placement of dental implants into infected versus non-infected sites were eligible for the study. Exclusion criteria were: papers in which the survival rate was not the primary outcome; papers without a control group; studies with less than one year of follow-up; studies whose patients did not receive antibiotic therapy; studies with medically compromised patients; duplicated papers. Risk of bias assessment was performed with the Cochrane Collaboration tool. RESULTS: Of the 3.253 initial hits, 8 studies were included in both qualitative and quantitative synthesis (kappa=0.90; very good agreement). Forest plot for implant failure showed that immediate implants placed into infected sites presented a statistically significant risk of failure that is almost 3 times higher than when placed into non-infected sites (risk ratio= 2.99; 95% confidence interval: 1.04, 8.56; p= 0.04; 935 implants; i2= 0%). Peri-implant outcomes showed no statistical difference. CONCLUSIONS: Immediate dental implants placed into infected sites presented a statistically significant higher risk of failure than immediate dental implants placed into non-infected sites. Peri-implant outcomes were not statistically affected in this intervention.


Asunto(s)
Implantes Dentales , Carga Inmediata del Implante Dental , Implantación Dental Endoósea , Fracaso de la Restauración Dental , Humanos , Resultado del Tratamiento
14.
Phys Chem Chem Phys ; 20(35): 22652-22659, 2018 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-30132483

RESUMEN

The realization of the Quantum anomalous Hall effect (QAHE) in two dimensional (2D) metal organic frameworks (MOFs), (MC4S4)3 with M = Mn, Fe, Co, Ru and Rh, has been investigated based on a combination of first-principles calculations and tight binding models. Our analysis of the magnetic anisotropy energy (MAE) reveals that the out-of-plane (in-plane) magnetization is favored for M = Mn, Fe, and Ru (Co, and Rh). Therefore, we predict that the structural symmetry of (MC4S4)3 yields the QAHE only for M = Mn, Fe and Ru. Such a quantum anomalous Hall phase has been confirmed through the calculation of the Chern number, and examining the formation of topologically protected (metallic) edge states. Furthermore, we show that viable electron (n-type) doping of the MOFs can be used to place the Fermi level within the non-trivial energy gap; where we find that in (RuC4S4)3, in addition to the up-shift of the Fermi level, the MAE energy increases by 40%. Finally, we show that in MOF/graphene (vdW) interfaces, the Fermi level tuning can be done with an external electric field, which controls the charge transfer at the MOF/graphene interface, giving rise to switchable topologically protected edge currents in the MOFs.

15.
J Chem Phys ; 147(17): 174704, 2017 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-29117701

RESUMEN

Layered clay materials have been used to incorporate transition metal (TM) contaminants. Based on first-principles calculations, we have examined the energetic stability and the electronic properties due to the incorporation of Cd and Hg in layered clay materials, kaolinite (KAO) and pyrophyllite (PYR). The TM can be (i) adsorbed on the clay surface as well as (ii) intercalated between the clay layers. For the intercalated case, the contaminant incorporation rate can be optimized by controlling the interlayer spacing of the clay, namely, pillared clays. Our total energy results reveal that the incorporation of the TMs can be maximized through a suitable tuning of vertical distance between the clay layers. Based on the calculated TM/clay binding energies and the Langmuir absorption model, we estimate the concentrations of the TMs. Further kinetic properties have been examined by calculating the activation energies, where we found energy barriers of ∼20 and ∼130 meV for adsorbed and intercalated cases, respectively. The adsorption and intercalation of ionized TM adatoms were also considered within the deprotonated KAO surface. This also leads to an optimal interlayer distance which maximizes the TM incorporation rate. By mapping the total charge transfers at the TM/clay interface, we identify a net electronic charge transfer from the TM adatoms to the topmost clay surface layer. The effect of such a charge transfer on the electronic structure of the clay (host) has been examined through a set of X-ray absorption near edge structure (XANES) simulations, characterizing the changes of the XANES spectra upon the presence of the contaminants. Finally, for the pillared clays, we quantify the Cd and Hg K-edge energy shifts of the TMs as a function of the interlayer distance between the clay layers and the Al K-edge spectra for the pristine and pillared clays.

16.
ScientificWorldJournal ; 2015: 396962, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25874244

RESUMEN

The aim of this study is to evaluate the temperature change on specimens of primary enamel irradiated with different pulse duration of Nd:YAG laser. Fifteen sound primary molars were sectioned mesiodistally, resulting in 30 specimens (3.5 × 3.5 × 2.0 mm). Two small holes were made on the dentin surface in which K-type thermocouples were installed to evaluate thermal changes. Specimens were randomly assigned in 3 groups (n = 10): A = EL (extra long pulse, 10.000 µs), B = LP (long pulse, 700 µs), and C = SP (short pulse, 350 µs). Nd:YAG laser (λ = 1.064 µm) was applied at contact mode (10 Hz, 0.8 W, 80 mJ) and energy density of 0.637 mJ/mm(2). Analysis of variance (ANOVA) was performed for the statistical analysis (P = 0.46). Nd:YAG laser pulse duration provided no difference on the temperature changes on primary enamel, in which the following means were observed: A = EL (23.15°C ± 7.75), B = LP (27.33°C ± 11.32), and C = SP (26.91°C ± 12.85). It can be concluded that the duration of the laser pulse Nd:YAG increased the temperature of the primary enamel but was not influenced by different pulse durations used in the irradiation.


Asunto(s)
Esmalte Dental/fisiología , Láseres de Estado Sólido , Temperatura , Humanos , Láseres de Estado Sólido/normas , Factores de Tiempo
17.
J Neonatal Perinatal Med ; 17(4): 575-582, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38905060

RESUMEN

BACKGROUND: Fetal inflammatory response syndrome (FIRS), the fetal equivalent of chorioamnionitis, is associated with poorer neonatal outcomes. FIRS is diagnosed through placental histology, namely by the identification of funisitis (inflammation of the umbilical cord) and chorionic vasculitis (inflammation of fetal vessels within the chorionic plate). The aim of this study was to identify and evaluate associations between FIRS and neonatal outcomes in preterm neonates. METHODS: We performed a retrospective cohort study at a level III neonatal intensive care unit (NICU), from January 1st 2008 to December 31st 2022, involving all inborn neonates with a gestational age below 30 weeks. We compared preterm neonates based on whether their placental histology described funisitis with chorionic vasculitis (FCV) or not. RESULTS: The study included 113 preterms, 27 (23.9%) of those had FCV and 86 (76.1%) did not. After adjusting to gestational age, prolonged rupture of membranes and preeclampsia, FCV was independently associated with the development of early-onset sepsis (OR = 7.3, p = 0.021) and cystic periventricular leukomalacia (OR = 4.6, p = 0.004). CONCLUSION: The authors identified an association between FIRS and the development of early-onset sepsis and cystic periventricular leukomalacia, highlighting the importance of early detection and management of this condition in order to improve long-term neonatal outcomes.


Asunto(s)
Corioamnionitis , Recien Nacido Prematuro , Leucomalacia Periventricular , Humanos , Femenino , Recién Nacido , Estudios Retrospectivos , Embarazo , Corioamnionitis/diagnóstico , Masculino , Edad Gestacional , Placenta/patología , Sepsis Neonatal/diagnóstico , Sepsis/diagnóstico , Unidades de Cuidado Intensivo Neonatal , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico , Adulto
18.
Int J Oral Maxillofac Surg ; 52(1): 118-131, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35840447

RESUMEN

The aim of this systematic review was to determine the prevalence of the canalis sinuosus (CS) and accessory canals of the canalis sinuosus (ACCS) as identified on cone beam computed tomography (CBCT). Online searches were conducted in the MEDLINE (via PubMed), Scopus, LILACS, Cochrane CENTRAL, Web of Science, and SIGLE (via OpenGrey) databases. Primary studies that determined the prevalence of canalis sinuosus and/or its anatomical variations using CBCT were included. The risk of bias assessment was performed using the AQUA tool. The quality effects model using double arcsine transformation was used for the meta-analysis of prevalence. Heterogeneity, publication bias, and sensitivity analyses were performed. Of 3237 initial results, 17 papers were included for systematic review. The meta-analysis comprising 1994 patients showed a pooled prevalence of CS of 0.80 (95% confidence interval (CI) 0.51-0.99; P = 0.001; I2 = 99%). Publication bias analysis revealed minor asymmetry (LFK index 1.84). The meta-analysis of 4605 patients showed a pooled prevalence of ACCS of 0.54 (95% CI 0.38-0.69; P = 0.001; I2 = 99%). The sensitivity analysis showed a pooled prevalence of ACCS of 0.53 (95% CI 0.32-0.74; P = 0.001; I2 = 99%) for studies with ≥ 1000 patients and 0.55 (95% CI 0.33-0.76; P = 0.001; I2 = 98%) for studies with< 1000 patients. Canalis sinuosus showed a pooled prevalence of 0.80 and ACCS showed a pooled prevalence of 0.54; hence both should be considered as anatomical structures, which means that they are present in most people. Surgeons must be aware of the CS and ACCS on CBCT analysis during pre-surgical planning. PROSPERO REGISTRATION NUMBER: CRD42020154195.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Maxilar , Humanos , Prevalencia , Tomografía Computarizada de Haz Cónico/métodos , Bibliometría
19.
Lasers Surg Med ; 43(5): 410-20, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21674546

RESUMEN

BACKGROUND AND OBJECTIVE: It is unknown if pro- and anti-inflammatory mediators in acute lung inflammation induced by intestinal ischemia and reperfusion (i-I/R) can be modulated by low-level laser therapy (LLLT). STUDY DESIGN/MATERIAL AND METHODS: A controlled ex vivo study was developed in which rats were irradiated (660 nm, 30 mW, 0.08 cm² of spot size) on the skin over the right upper bronchus 1 hour post-mesenteric artery occlusion and euthanized 4 hours later. For pretreatment with anti-tumor necrosis factor (TNF) or IL-10 antibodies, the rats received either one of the agents 15 minutes before the beginning of reperfusion. METHODS: Lung edema was measured by the Evans blue extravasation and pulmonary neutrophils influx was determined by myeloperoxidase (MPO) activity. Both TNF and IL-10 expression and protein in lung were evaluated by RT-PCR and ELISA, respectively. RESULTS: LLLT reduced the edema (80.1 ± 41.8 µg g⁻¹ dry weight), neutrophils influx (0.83 ± 0.02 × 106 cells ml⁻¹), MPO activity (2.91 ± 0.60), and TNF (153.0 ± 21.0 pg mg⁻¹ tissue) in lung when compared with respective control groups. Surprisingly, the LLLT increased the IL-10 (0.65 ± 0.13) in lung from animals subjected to i-I/R. Moreover, LLLT (0.32 ± 0.07 pg ml⁻¹) reduced the TNF-α level in RPAECs when compared with i-I/R group. The presence of anti-TNF or IL-10 antibodies did not alter the LLLT effect on IL-10 (465.1 ± 21.0 pg mg⁻¹ tissue) or TNF (223.5 ± 21.0 pg mg⁻¹ tissue) in lung from animals submitted to i-I/R. CONCLUSION: The results indicate that the LLLT attenuates the i-I/R-induced acute lung inflammation which favor the IL-10 production and reduce TNF generation.


Asunto(s)
Interleucina-10/biosíntesis , Intestinos/irrigación sanguínea , Isquemia/complicaciones , Terapia por Luz de Baja Intensidad , Neumonía/radioterapia , Reperfusión , Factor de Necrosis Tumoral alfa/biosíntesis , Enfermedad Aguda , Animales , Edema , Láseres de Semiconductores/uso terapéutico , Pulmón/metabolismo , Pulmón/patología , Pulmón/efectos de la radiación , Masculino , Neutrófilos/efectos de la radiación , Peroxidasa/biosíntesis , Neumonía/etiología , Neumonía/metabolismo , Neumonía/patología , Distribución Aleatoria , Ratas , Ratas Wistar
20.
Nanoscale ; 13(10): 5270-5274, 2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33662069

RESUMEN

A material's geometric structure is a fundamental part of its properties. The honeycomb geometry of graphene is responsible for its Dirac cone, while kagome and Lieb lattices host flat bands and pseudospin-1 Dirac dispersion. These features seem to be particular to a few 2D systems rather than a common occurrence. Given this correlation between structure and properties, exploring new geometries can lead to unexplored states and phenomena. Kepler is the pioneer of the mathematical tiling theory, describing ways of filling the Euclidean plane with geometric forms in his book Harmonices Mundi. In this article, we characterize 1255 lattices composed of k-uniform tiling of the Euclidean plane and unveil their intrinsic properties; this class of arranged tiles presents high-degeneracy points, exotic quasiparticles and flat bands as common features. Here, we present a guide for the experimental interpretation and prediction of new 2D systems.

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