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The dental implant surface plays a crucial role in osseointegration. The topography and physicochemical properties will affect the cellular functions. In this research, four distinct titanium surfaces have been studied: machined acting (MACH), acid etched (AE), grit blasting (GBLAST), and a combination of grit blasting and subsequent acid etching (GBLAST + AE). Human amniotic mesenchymal (hAMSCs) and epithelial stem cells (hAECs) isolated from the amniotic membrane have attractive stem-cell properties. They were cultured on titanium surfaces to analyze their impact on biological behavior. The surface roughness, microhardness, wettability, and surface energy were analyzed using interferometric microscopy, Vickers indentation, and drop-sessile techniques. The GBLAST and GBLAST + AE surfaces showed higher roughness, reduced hydrophilicity, and lower surface energy with significant differences. Increased microhardness values for GBLAST and GBLAST + AE implants were attributed to surface compression. Cell viability was higher for hAMSCs, particularly on GBLAST and GBLAST + AE surfaces. Alkaline phosphatase activity enhanced in hAMSCs cultured on GBLAST and GBLAST + AE surfaces, while hAECs showed no mineralization signals. Osteogenic gene expression was upregulated in hAMSCs on GBLAST surfaces. Moreover, α2 and ß1 integrin expression enhanced in hAMSCs, suggesting a surface-integrin interaction. Consequently, hAMSCs would tend toward osteoblastic differentiation on grit-blasted surfaces conducive to osseointegration, a phenomenon not observed in hAECs.
Assuntos
Âmnio , Implantes Dentários , Propriedades de Superfície , Titânio , Humanos , Titânio/química , Âmnio/citologia , Âmnio/metabolismo , Osteogênese , Diferenciação Celular , Células Cultivadas , Osseointegração , Células-Tronco/citologia , Células-Tronco/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Sobrevivência Celular , Fosfatase Alcalina/metabolismoRESUMO
Background: Vestibular symptoms on sitting-up are frequent on patients seen by vestibular specialists. Recently, a benign paroxysmal positional vertigo (BPPV) variant which elicits vestibular symptoms with oculomotor evidence of posterior semicircular canal (P-SCC) cupula stimulation on sitting-up was described and named sitting-up vertigo BPPV. A periampullar restricted P-SCC canalolithiasis was proposed as a causal mechanism. Objective: To describe new mechanisms of action for the sitting-up vertigo BPPV variant. Methods: Eighteen patients with sitting-up vertigo BPPV were examined with a pre-established set of positional maneuvers and follow-up until they resolved their symptoms and clinical findings. Results: All patients showed up-beating torsional nystagmus (UBTN) and vestibular symptoms on coming up from either Dix-Hallpike (DHM) or straight head-hanging maneuver. Sixteen out of 18 patients presented a sustained UBTN with an ipsitorsional component to the tested side on half-Hallpike maneuver (HH). A slower persistent contratorsional down-beating nystagmus was found in eleven out 18 patients tested on nose down position (ND). Conclusions: Persistent direction changing positional nystagmus on HH and ND positions indicative of P-SCC heavy cupula was found in 11 patients. A sustained UBTN on HH with the absence of findings on ND, which is suggestive of the presence of P-SCC short arm canalolithiasis, was found on 5 patients. All patients were treated with canalith repositioning maneuvers without success, but they resolved their findings by means of Brandt-Daroff exercises. We propose P-SCC heavy cupula and P-SCC short arm canalolithiasis as two new putative mechanisms for the sitting-up vertigo BPPV variant.
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COVID-19 has affected millions of children and, while it was previously considered as a respiratory disease, neurologic involvement has also been documented. The objective of this study was to identify the neurological manifestations (NMs) and the outcomes of children with COVID-19 who attended the National Medical Center "20 de Noviembre". METHODS: A retrospective cohort study of children hospitalized for COVID-19 from April 2020 to March 2021 was conducted. Clinical-demographic data were registered. Neurologic manifestations were defined as any clinical neurological expression of the central and/or peripheral nervous system that occurred during admission or hospitalization. RESULTS: In total, 46 children with a confirmed COVID-19 result, 26 (56.5%) boys and 20 (43.5%) girls with a median age of 8.9 ± 4.6 years, constituted the study population. Half of the children showed some NMs, and this group of patients concomitantly showed acute lymphoblastic leukemia (ALL, 56%), obesity (17.3%), or acute myeloblastic leukemia (AML, 4.3%). The most frequently described NMs were headache (13, 56%), encephalopathy (10, 43.47%), and epilepsy (4, 17.39%). The mortality rate in children with NMs was 21.7% and they had a higher mortality rate when compared to those without NM p ≤ 0.025. CONCLUSIONS: NMs occurred predominantly in male children aged 6 to 12 years; ALL was the most frequent comorbidity. Headache prevailed and hypoxemia, hypocalcemia, elevated ferritin, and C-reactive protein were associated with NM. Finally, NMs were a risk factor for mortality.
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Worldwide, COVID-19 coronavirus disease is spreading rapidly in a second and third wave of infections. In this context of increasing infections, it is critical to know the probability of a specific number of cases being reported. We collated data on new daily confirmed cases of COVID-19 breakouts in: Argentina, Brazil, China, Colombia, France, Germany, India, Indonesia, Iran, Italy, Mexico, Poland, Russia, Spain, U.K., and the United States, from the 20th of January, 2020 to 28th of August 2021. A selected sample of almost ten thousand data is used to validate the proposed models. Generalized Extreme-Value Distribution Type 1-Gumbel and Exponential (1, 2 parameters) models were introduced to analyze the probability of new daily confirmed cases. The data presented in this document for each country provide the daily probability of rate incidence. In addition, the frequencies of historical events expressed as a return period in days of the complete data set is provided.
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We focus on the derivation of a general position-dependent effective diffusion coefficient to describe two-dimensional (2D) diffusion in a narrow and smoothly asymmetric channel of varying width under a transverse gravitational external field, a generalization of the symmetric channel case using the projection method introduced earlier by Kalinay and Percus [P. Kalinay and J. K. Percus, J. Chem. Phys. 122, 204701 (2005)10.1063/1.1899150]. To this end, we project the 2D Smoluchowski equation into an effective one-dimensional generalized Fick-Jacobs equation in the presence of constant force in the transverse direction. The expression for the diffusion coefficient given in Eq. (34) is our main result. This expression is a more general effective diffusion coefficient for narrow 2D channels in the presence of constant transverse force, which contains the well-known previous results for a symmetric channel obtained by Kalinay, as well as the limiting cases when the transverse gravitational external field goes to zero and infinity. Finally, we show that diffusivity can be described by the interpolation formula proposed by Kalinay, D_{0}/[1+(1/4)w^{'2}(x)]^{-η}, where spatial confinement, asymmetry, and the presence of a constant transverse force can be encoded in η, which is a function of channel width (w), channel centerline, and transverse force. The interpolation formula also reduces to well-known previous results, namely, those obtained by Reguera and Rubi [D. Reguera and J. M. Rubi, Phys. Rev. E 64, 061106 (2001)10.1103/PhysRevE.64.061106] and by Kalinay [P. Kalinay, Phys. Rev. E 84, 011118 (2011)10.1103/PhysRevE.84.011118].
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RESUMEN Introducción: aunque el microcarcinoma papilar de tiroides ha sufrido un aumento en la incidencia en las últimas décadas, todavía es una controversia la extensión de la resección de la glándula y el tratamiento oncológico. Objetivo: determinar la incidencia del microcarcinoma papilar de tiroides en enfermos operados de cáncer de tiroides en el Hospital "León Cuervo Rubio" de Pinar del Río, en el período entre enero de 2018 a marzo de 2020. Métodos: se realizó un estudio descriptivo y transversal de 22 enfermos operados de microcarcinoma de tiroides, a los cuales se les practicó una tiroidectomía total. Se tomaron los datos de las historias clínicas, informes operatorios y las biopsias. Se utilizaron los métodos de observación y analítico. Las variables analizadas fueron: tamaño del tumor, resultados de la BAAF, diagnóstico definitivo, variedad histológica, enfermedades de tiroides asociadas y extensión de la enfermedad Resultados: los 22 enfermos operados de microcarcinoma de tiroides representan el 42,30 % del total de caso operados por cáncer. Predomina el sexo femenino y edad promedio 49,9 años. El 31,81 % de los enfermos con biopsia corresponden al grupo Bethesda I, II Y III; sin embargo, eran portadores de microcarcinomas. Un 18 % de los enfermos eran portadores de dos variedades histológicas de carcinoma. Conclusiones: el microcarcinoma papilar de tiroides aumenta su incidencia sobre todo en enfermos mayores de 45 años, con extensión más allá de la glándula lo cual agrava el pronóstico del enfermo, y requiere de la atención médica multidisciplinaria para determinar factores de riesgo pronóstico. De esta forma mejorar la conducta a seguir y la calidad de vida del paciente.
ABSTRACT Introduction: although papillary thyroid microcarcinoma has suffered an increase in incidence in the last decades, the extension of gland resection and oncological treatment is still a controversy. Objective: to determine the incidence of papillary thyroid microcarcinoma in patients who have undergone surgery for thyroid cancer at Leon Cuervo Rubio Hospital in Pinar del Río, 2018-2020. Methods: a descriptive and cross-sectional study of 22 patients operated for thyroid microcarcinoma was carried out, who underwent a total thyroidectomy, collecting data from the clinical histories, surgery reports and biopsies. Observation and analysis approaches were used. Variables to be analyzed: size of the tumor, BAAF results, definitive diagnosis, histological variety, associated thyroid diseases and extension of the disease Results: the 22 patients operated on thyroid microcarcinoma represented 42.30% of the total number of cases operated for cancer reasons. Female sex predominated and average age is 49.9 years; 31.81% of the patients with biopsy correspond to the Bethesda I, II and III group, however they were carriers of microcarcinoma; 18% of the patients were carriers of two histological varieties of carcinoma. Conclusions: papillary thyroid microcarcinoma continues the increase of its incidence, especially in patients over 45 years old, with extension beyond the gland, which aggravates the prognosis of the patient suffering from it and requires multidisciplinary medical care to determine prognostic risk factors and to improve the behavior to be followed and the quality of life of the patient.
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RESUMEN El Síndrome de Wiskott-Aldrich es una inmunodeficiencia hereditaria poco frecuente, acompañada de trombocitopenia. Así mismo, el absceso de tiroides se presenta raras veces, dados los niveles de iodo, irrigación linfática y lo encapsulado del órgano. El objetivo del presente trabajo es presentar el caso de un paciente con absceso de la glándula tiroides, que además era portador de Síndrome de Wiskott-Aldrich. De sexo masculino y 21 años de edad, fue atendido en el Hospital León Cuervo Rubio, de Pinar del Río. Una semana antes había sufrido un ántrax en la espalda, seguido del aumento de volumen del cuello y signos de compresión, aunque sin indicios de sepsis. Durante la intervención quirúrgica se encontró absceso de la glándula tiroides. El tratamiento oportuno del absceso de tiroides evita consecuencias fatales en enfermos inmunodeprimidos, como el paciente presentado.
ABSTRACT Wiskott-Aldrich Syndrome is a rare inherited immunodeficiency, accompanied by thrombocytopenia. In addition, thyroid abscess occurs rarely, given the levels of iodine, lymphatic irrigation and the encapsulation of the organ. The objective of this work is to present the case of a patient with an abscess of the thyroid gland, who was also a carrier of Wiskott-Aldrich syndrome. A 21 years old male was treated at the León Cuervo Rubio Hospital, in Pinar del Río. A week earlier, he had suffered a anthrax on his back, followed by swelling in his neck and signs of compression, but with no signs of sepsis. During the surgical intervention, an abscess of the thyroid gland was found. Timely treatment of thyroid abscess avoids fatal consequences in immunodeficient patients, such as the patient presented.
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In mating interactions, it is common in nature for both sexes to choose simultaneously. However, this mutual mate choice and its consequences for progeny has received relatively little study; an approach where both male and female condition is manipulated is thus desirable. We compared both sexes' preferences in Tenebrio molitor beetles when individual condition varied (healthy vs infected with a fungus), and observed the direct benefits of those preferences. We predicted that: (a) females and males in good condition would prefer high quality mates; (b) preferences would be weaker when the choosing individual is in poor condition (and thus less selective given, for example, time and energetic constrains); and, (c) high quality mates would lay a larger number of total eggs and/or viable eggs than low quality mates. We found that both males and females in good condition were not more likely to choose mates that were also in good condition. However, poor-condition animals were more likely to prefer similar quality animals, while high-condition animals did not necessarily prefer mates of similar condition. Choosing sick males or females had a negative impact on egg number and viability. Our results suggest a non-adaptive mate choice in this species. Possibly, a deteriorated condition may drive individuals to invest more in attracting mates, because their chances of surviving the infection are very low. However, we do not discount the possibility that the fungus is manipulating individuals to increase its transmission during mating.
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Preferência de Acasalamento Animal/fisiologia , Comportamento Sexual Animal/fisiologia , Tenebrio/fisiologia , Comunicação Animal , Animais , Corte , Feminino , Interações Hospedeiro-Patógeno , Masculino , Metarhizium/fisiologia , Reprodução/fisiologia , Tenebrio/microbiologiaRESUMO
El crecimiento de la población humana y las actividades antropogénicas ha aumentado la tasa de contaminación del agua subterránea en el mundo, por lo que, la finalidad de este estudio es determinar la potabilidad del agua de cuatro pozos subterráneos de un área rural del estado Mérida, mediante la caracterización fisicoquímica y microbiológica, para comprobar la factibilidad de su uso como agua de consumo. Los resultados indican que los parámetros fisicoquímicos cumplen la normativa venezolana. Las aguas presentan una gran variedad de minerales destacándose Ca, Na y Mg como cationes mayoritarios y una dureza básicamente debía a iones bicarbonato. Los valores de la distribución isotópica, sugieren la existencia de dos acuíferos sin conexiones hidráulicas entre los pozos. El análisis bacteriológico y parasitológico detecta: bacterias heterótrofas, coliformes totales y Pseudomonas, así como, Ascaris spp., Blastocystis sp., Giardia sp., y Eimeria sp., probablemente procedentes del filtrado subterráneo de los pozos sépticos y percolado desde la superficie a través del suelo de textura franco arcilloso arenoso, microorganismos que se han adaptado a las características fisicoquímicas de las aguas. Los resultados demuestran que el agua de tres pozos, no puede ser utilizada para el consumo, sin previo tratamiento convencional como coagulación, filtración y cloración
Growth in human population and anthropogenic activities has increased the rate of groundwater pollution in the world, therefore, the purpose of this study is to determine the potability of water from four underground wells in a rural area of Mérida State, through the physicochemical and microbiological characterization, to check the feasibility of its use as drinking water. The results indicate that the physicochemical parameters comply with venezuelan regulations. The waters have a wide variety of minerals, highlighting Ca, Na and Mg as majority cations and a hardness basically due to bicarbonate ions. The values of the isotopic distribution suggest the existence of two aquifers without hydraulic connections between wells. Bacteriological and parasitological analysis detects: heterotrophic bacteria, total coliforms and Pseudomonas, as well as Ascaris spp., Blastocystis sp., Giardia sp., and Eimeria sp., probably derived from the underground filtration of septic tanks and percolated from the surface through the sandy clay loam soil, microorganisms that have adapted to the physicochemical characteristics of waters. The results show that the water from three wells cannot be used for consumption without some conventional treatment as filtration and coagulation, and disinfection process
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OBJECTIVE: To describe a variant of posterior canal benign paroxysmal positional vertigo (BPPV). STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: Fifteen patients with symptoms of BPPV and oculomotor evidence of activation of posterior semicircular canal (P-SCC) cupula that arises when sitting up from Dix-Hallpike maneuver (DH). INTERVENTION: All patients were examined with videonystagmography and underwent brain magnetic resonance imaging (MRI). RESULTS: All patients showed up-beating nystagmus with ipsilateral torsional component when coming up from right or left side DH. Most patients described vertiginous symptoms when sitting up from bed and many described severe non-positional disequilibrium. Eight patients had been treated with Epley canalith repositioning maneuver (CRM) at our clinic for posterior canal BPPV. Four of them were re-tested within an hour for CRM effectiveness and the rest, a week later. Three patients had been diagnosed with BPPV and were being treated with CRM in other institutions. Four patients showed these findings but they had not previously undergone CRM. All patients were treated with CRM without success, but they resolved their positional vertigo by means of Brandt Daroff exercises. No patient showed evidence of central vestibular disorder. CONCLUSION: We propose a P-SCC canalolithiasis limited to the periampullar portion by means of an anatomical restriction of distal movement of the otoconial debris. This syndrome seems to be more frequent early after CRM of classical P-SCC canalolithiasis. Close attention to ocular movement on sitting up after DH on patients is warranted.