Effect of intestinal pressure on fistula closure during vacuum assisted treatment: A computational approach

AbstractBackgroundEnterocutaneous fistulae, pathological communications between the intestinal lumen and the abdominal skin, can arise as serious complication of gastrointestinal surgery. A current non-surgical treatment for this pathology involves topical application of sub-atmospheric pressure, also known as vacuum assisted closure (VAC). While this technique appears to be promising, surgeons report a number of cases in which its application fails to achieve fistula closure. Here, we evaluate the fistula’s physical properties during the vacuum assisted closure process in a computational approach exploring the relevance of intraluminal intestinal pressure.MethodsA mathematical model formulated by differential equations based on tissue elasticity properties and principles of fluid mechanics was created and forcing functions were integrated to mimic intestinal pressure dynamics. A software to solve equations and to fit the model to experimentally obtained data was developed. This enabled simulations of vacuum assisted fistula closure under different intestinal pressure.ResultsThe simulation output indicates conditions, in which fistula closure can or cannot be expected suggesting favoured or impeded healing, respectively. When modifications of intestinal pressure, as observed in fistula accompanying pathologies, are integrated, the outcome of fistula closure changes considerably. Rise of intestinal pressure is associated with delay of fistula closure and temporary fistula radius augmentation, while reduction of intestinal pressure during sub-atmospheric pressure treatment contributes to a faster and direct fistula closure.ConclusionFrom the model predictions, we conclude that administration of intestinal pressure decreasing compounds (e.g. butylscopolamine, glucagon) may improve VAC treatment, while intestinal pressure increasing drugs should be avoided

Forage Accumulation and Quality of Three Contrasting Ecotypes of Tall Fescue (\u3ci\u3eSchedonorus arundinaceus\u3c/i\u3e) Managed under Frequent Defoliation

In the past, tall fescue ecotypes were compared under intermediate management defoliation frequency, but now has station, Argentina (-33 ° 56 \u27S, -60 ° 33\u27 W) in autumn 2016, on a typical Argiudoll soil. The treatments were cultivars representing three ecotypes of tall fescue: (i) - Mediterranean (cv. Flecha), (ii) - Intermediate (cv. Royal Q 100) and (iii) - Continental (cv. Lujan INTA). Each plot consisted of 7 rows 6.0 m long, 0.2 m apart (8.4m2 plot size) arranged in a randomized complete block design with 4 replicates. The first cut was done at the end of September when pastures reached \u3e 90 % of soil cover. The following six cuts were done when thermal time was 550°±50°C degree days (base temperature=4°C). The forage accumulation was determined by cutting with a mowing machine the central 5 m2 of each plot, at a height of 0.05 m. A sample (0.250 g) was taken to analyze in vitro dry matter digestibility (IVDIG), crude protein (CP), neutral detergent fiber (NDF) and NDF digestibility (NDFDIG). Mixed model was applied to consider ecotype and time effects. Ecotype*time interaction was significant for all variables (p\u3c 0.0001) except for forage accumulation. The values ranged between 491 and 2,625 kg DM ha-1 for forage accumulation, while IVDIG ranged between 57.2 and 68.7%, CP between 11.5 and 19.1%, NDF between 45.5 and 62.8% and NDFDIG between 26 and 65.3%. The Mediterranean ecotype produced less forage but in many cuts with higher CP. In many cuts, IVDIG was higher in the Continental ecotype associated with less leaf diseases

Effect of intestinal pressure on fistula closure during vacuum assisted treatment: A computational approach

Background: Enterocutaneous fistulae, pathological communications between the intestinal lumen and the abdominal skin, can arise as serious complication of gastrointestinal surgery. A current non-surgical treatment for this pathology involves topical application of sub-atmospheric pressure, also known as vacuum assisted closure (VAC). While this technique appears to be promising, surgeons report a number of cases in which its application fails to achieve fistula closure. Here, we evaluate the fistula's physical properties during the vacuum assisted closure process in a computational approach exploring the relevance of intraluminal intestinal pressure. Methods: A mathematical model formulated by differential equations based on tissue elasticity properties and principles of fluid mechanics was created and forcing functions were integrated to mimic intestinal pressure dynamics. A software to solve equations and to fit the model to experimentally obtained data was developed. This enabled simulations of vacuum assisted fistula closure under different intestinal pressure. Results: The simulation output indicates conditions, in which fistula closure can or cannot be expected suggesting favoured or impeded healing, respectively. When modifications of intestinal pressure, as observed in fistula accompanying pathologies, are integrated, the outcome of fistula closure changes considerably. Rise of intestinal pressure is associated with delay of fistula closure and temporary fistula radius augmentation, while reduction of intestinal pressure during sub-atmospheric pressure treatment contributes to a faster and direct fistula closure. Conclusion: From the model predictions, we conclude that administration of intestinal pressure decreasing compounds (e.g. butylscopolamine, glucagon) may improve VAC treatment, while intestinal pressure increasing drugs should be avoided.Facultad de Ciencias ExactasInstituto de Física de Líquidos y Sistemas Biológico

Comparison of multiple techniques for endobronchial ultrasound-transbronchial needle aspiration specimen preparation in a single institution experience.

The optimal method for specimen preparation of endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) is still controversial. This study aims to compare several techniques available for EBUS-TBNA specimen acquisition and processing, in order to identify the best performing technique. We retrospectively reviewed the data of 199 consecutive patients [male, 73%; median age, 64 years (IQR: 52-74 years)] undergoing EBUS-TBNA at our institution from 2012 through 2014 for diagnosis of hilar-mediastinal lymph node enlargement suspect of neoplastic (n=139) or granulomatous (n=60) disease. All procedures were performed by two experienced bronchoscopists, under conscious sedation and local anaesthesia, using 21/22-Gauge (G) needle, without rapid on-site evaluation (ROSE). Five specimen-processing techniques were used: cytology slides in 42 cases (21%); cell-block in 25 (13%); core-tissue in 60 (30%); combination of cytology slides and core-tissue in 51 (26%); combination of cytology slides and cell-block in 21 (10%). To assess the diagnostic accuracy of each tissue-processing technique we compared the EBUS-TBNA results to those obtained with surgical lymphadenectomy, or 1-year follow-up in non-operated patients. Diagnostic yield, accuracy and area under the curve (AUC) were as follows. Cytology slides: 81%, 80%, 0.90; cell-block: 48%, 33%, 0.67; core-tissue: 87%, 99%, 0.96; cytology slides + core-tissue: 80%, 100%, 1.00; cytology slides + cell-block: 86%, 100%, 1.00. Cytology slides and core-tissue method showed non-significantly different diagnostic yield (P=0.435) and AUC (P=0.152). In our single-institution experience, cytology slides and core-tissue preparations demonstrated high and similar diagnostic performance. Cytology slides combination with core-tissue or cell-block showed the highest performance, however these combination methods were more resource-consuming

Effect of intestinal pressure on fistula closure during vacuum assisted treatment: A computational approach

Background: Enterocutaneous fistulae, pathological communications between the intestinal lumen and the abdominal skin, can arise as serious complication of gastrointestinal surgery. A current non-surgical treatment for this pathology involves topical application of sub-atmospheric pressure, also known as vacuum assisted closure (VAC). While this technique appears to be promising, surgeons report a number of cases in which its application fails to achieve fistula closure. Here, we evaluate the fistula's physical properties during the vacuum assisted closure process in a computational approach exploring the relevance of intraluminal intestinal pressure. Methods: A mathematical model formulated by differential equations based on tissue elasticity properties and principles of fluid mechanics was created and forcing functions were integrated to mimic intestinal pressure dynamics. A software to solve equations and to fit the model to experimentally obtained data was developed. This enabled simulations of vacuum assisted fistula closure under different intestinal pressure. Results: The simulation output indicates conditions, in which fistula closure can or cannot be expected suggesting favoured or impeded healing, respectively. When modifications of intestinal pressure, as observed in fistula accompanying pathologies, are integrated, the outcome of fistula closure changes considerably. Rise of intestinal pressure is associated with delay of fistula closure and temporary fistula radius augmentation, while reduction of intestinal pressure during sub-atmospheric pressure treatment contributes to a faster and direct fistula closure. Conclusion: From the model predictions, we conclude that administration of intestinal pressure decreasing compounds (e.g. butylscopolamine, glucagon) may improve VAC treatment, while intestinal pressure increasing drugs should be avoided.Facultad de Ciencias ExactasInstituto de Física de Líquidos y Sistemas Biológico

Adult facial anthropometric measurements according to facial type and gender

Objetivo: descrever medidas antropométricas faciais de adultos, segundo tipo facial e sexo. Método: participaram 105 adultos leucodermas, 34 (32,4%) homens e 71 (67,6%) mulheres, com idades entre 20 e 40 anos, de uma clínica particular de ortodontia de Belo Horizonte, Minas Gerais. Foram comparados os achados da análise cefalométrica para determinação do tipo de face com sete medidas antropométricas faciais diretas: altura facial anterior- násio ao mentoniano; distância bizigomáticazigomático esquerdo ao direito; altura do terço facial inferior- subnasal ao mentoniano; altura da face média- násio ao estômio; altura do queixo- supramentoniano ao mentoniano; altura da face inferiorestômio ao mentoniano; e altura facial posterior- condílio ao gônio. Resultados: para o sexo masculino, os tipos faciais classificados por meio da cefalometria apresentaram diferenças estatisticamente significantes para os valores médios das medidas antropométricas: altura facial anterior, altura do terço facial inferior, altura da face média e altura da face inferior. Para o sexo feminino, diferenças estatisticamente significantes foram encontradas nas medidas: altura facial anterior, altura do terço facial inferior, altura da face média, altura da face inferior e altura facial posterior. Conclusão: houve dimorfismo sexual para todas as medidas antropométricas obtidas, as quais tiveram valores médios maiores para o sexo masculino quando comparados ao feminino. Os tipos faciais classificados por meio da cefalometria apresentaram diferenças estatisticamente significantes para quatro medidas antropométricas do sexo masculino e cinco do feminino.132245252COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESSem informaçãoPurpose: to describe anthropometric measurements in adults according to facial type and gender. Method: 105 Caucasian adults took part, 34 male (32.4%) and 71 female (67.6%) with ages between 20 and 40-year old, in a private orthodontic clinic in Belo Horizonte, Minas Gerais, Brazil. The findings from the cephalometric analysis were compared for determining facial type with seven direct anthropometric measurements: anterior face height- nasion to menton; distance bizygomatiquezygion left to right; lower face height- subnasale to menton; middle face height- nasion to stomion; chin height- supramenton to menton; inferior face height- stomion to menton; and posterior face heightcondylion to gonion. Results: for male, the facial types classified by means of cephalometry had significant statistical differences for the average values of the anthropometric measurements: anterior face height, lower face height, middle face height and inferior face height. For female, significant statistical differences were found in the following measurements: anterior face height, lower face height, middle face height, inferior face height and posterior face height. Conclusion: there was sexual dimorphism for all collected anthropometric measurements. The male showed higher average values when compared with the female. The facial types classified by means of cephalometry showed significant statistical differences in four anthropometric measurements, for male and five for female

Adult facial anthropometric measurements according to facial type and gender

PURPOSE: to describe anthropometric measurements in adults according to facial type and gender. METHODS: 105 Caucasian adults took part, 34 male (32.4%) and 71 female (67.6%) with ages between 20 and 40-year old, in a private orthodontic clinic in Belo Horizonte, Minas Gerais, Brazil. The findings from the cephalometric analysis were compared for determining facial type with seven direct anthropometric measurements: anterior face height- nasion to menton; distance bizygomatique- zygion left to right; lower face height- subnasale to menton; middle face height- nasion to stomion; chin height- supramenton to menton; inferior face height- stomion to menton; and posterior face height- condylion to gonion. RESULTS: for male, the facial types classified by means of cephalometry had significant statistical differences for the average values of the anthropometric measurements: anterior face height, lower face height, middle face height and inferior face height. For female, significant statistical differences were found in the following measurements: anterior face height, lower face height, middle face height, inferior face height and posterior face height. CONCLUSION: there was sexual dimorphism for all collected anthropometric measurements. The male showed higher average values when compared with the female. The facial types classified by means of cephalometry showed significant statistical differences in four anthropometric measurements, for male and five for female.OBJETIVO: descrever medidas antropométricas faciais de adultos, segundo tipo facial e sexo. MÉTODOS: participaram 105 adultos leucodermas, 34 (32,4%) homens e 71 (67,6%) mulheres, com idades entre 20 e 40 anos, de uma clínica particular de ortodontia de Belo Horizonte, Minas Gerais. Foram comparados os achados da análise cefalométrica para determinação do tipo de face com sete medidas antropométricas faciais diretas: altura facial anterior- násio ao mentoniano; distância bizigomática- zigomático esquerdo ao direito; altura do terço facial inferior- subnasal ao mentoniano; altura da face média- násio ao estômio; altura do queixo- supramentoniano ao mentoniano; altura da face inferior- estômio ao mentoniano; e altura facial posterior- condílio ao gônio. RESULTADOS: para o sexo masculino, os tipos faciais classificados por meio da cefalometria apresentaram diferenças estatisticamente significantes para os valores médios das medidas antropométricas: altura facial anterior, altura do terço facial inferior, altura da face média e altura da face inferior. Para o sexo feminino, diferenças estatisticamente significantes foram encontradas nas medidas: altura facial anterior, altura do terço facial inferior, altura da face média, altura da face inferior e altura facial posterior. CONCLUSÃO: houve dimorfismo sexual para todas as medidas antropométricas obtidas, as quais tiveram valores médios maiores para o sexo masculino quando comparados ao feminino. Os tipos faciais classificados por meio da cefalometria apresentaram diferenças estatisticamente significantes para quatro medidas antropométricas do sexo masculino e cinco do feminino.13224525

A Two-Stage Model for Lipid Modulation of the Activity of Integral Membrane Proteins

Lipid-protein interactions play an essential role in the regulation of biological function of integral membrane proteins; however, the underlying molecular mechanisms are not fully understood. Here we explore the modulation by phospholipids of the enzymatic activity of the plasma membrane calcium pump reconstituted in detergent-phospholipid mixed micelles of variable composition. The presence of increasing quantities of phospholipids in the micelles produced a cooperative increase in the ATPase activity of the enzyme. This activation effect was reversible and depended on the phospholipid/detergent ratio and not on the total lipid concentration. Enzyme activation was accompanied by a small structural change at the transmembrane domain reported by 1-aniline-8-naphtalenesulfonate fluorescence. In addition, the composition of the amphipilic environment sensed by the protein was evaluated by measuring the relative affinity of the assayed phospholipid for the transmembrane surface of the protein. The obtained results allow us to postulate a two-stage mechanistic model explaining the modulation of protein activity based on the exchange among non-structural amphiphiles at the hydrophobic transmembrane surface, and a lipid-induced conformational change. The model allowed to obtain a cooperativity coefficient reporting on the efficiency of the transduction step between lipid adsorption and catalytic site activation. This model can be easily applied to other phospholipid/detergent mixtures as well to other membrane proteins. The systematic quantitative evaluation of these systems could contribute to gain insight into the structure-activity relationships between proteins and lipids in biological membranes