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La evaluación de la marcha en cinta caminadora puede resultar relevante para la toma de decisiones clínicas. No obstante, factores demográficos como la edad y el IMC pueden alterar la interpretación de los resultados. Nuestro objetivo fue obtener variables espacio- temporales, energéticas y costo de transporte durante la velocidad autoseleccionada en cinta caminadora para una muestra representativa de adultos uruguayos (n=28) y evaluar si diferentes rangos de edades e IMC pueden ser factores a tener en cuenta en pruebas clínicas donde se consideren dichas variables. Participaron 17 hombres y 11 mujeres (39,3 ± 14,8 años, 75,9 ± 12,5 kg, 1,74 ± 0,09 m, IMC 25,2 ± 4,06). Se realizó una reconstrucción 3D del movimiento en forma sincronizada con el consumo energético. Se obtuvieron valores de referencia y luego de agrupar los participantes según su IMC y rango de edad se compararon los datos mediante test de t (p≤0.05). Los resultados revelaron discrepancias significativas en las medidas espacio-temporales y energéticas de los adultos uruguayos al caminar en cinta con respecto a la literatura. La marcha difiere entre adultos jóvenes y de mediana edad en su velocidad autoseleccionada (p=0,03), longitud de zancada (p=0,01), trabajo mecánico externo (<0,001) y recuperación de energía mecánica (0,009), destacando la importancia de considerar la edad en evaluaciones clínicas. El IMC no influyó significativamente en estas variables. Estos hallazgos subrayan la necesidad de ajustar las interpretaciones de las pruebas clínicas de la marcha sobre cinta caminadora en adultos uruguayos de mediana edad (45 a 65 años).
Treadmill gait assessment can be relevant for clinical decision-making. However, demographic factors such as age and BMI may alter result interpretation. Our aim was to obtain spatiotemporal, energetic, and cost of transport variables during self-selected treadmill walking speed for a representative sample of Uruguayan adults (n=28) and to assess if different age ranges and BMI could be factors to consider in clinical tests involving these variables. Seventeen men and eleven women participated (39.3 ± 14.8 years, 75.9 ± 12.5 kg, 1.74 ± 0.09 m, BMI 25.2 ± 4.06). A synchronized 3D motion reconstruction was performed with energy consumption. Reference values were obtained and data were compared using t-tests (p≤0.05), after grouping participants by BMI and age range. Results revealed significant discrepancies in spatiotemporal and energetic measures of Uruguayan adults walking on the treadmill, compared to the literature. Gait differed between young and middle-aged adults in their self-selected speed (p=0.03), stride length (p=0.01), external mechanical work (p<0.001), and mechanical energy recovery (0.009), emphasizing the importance of considering age in clinical evaluations. BMI did not significantly influence these variables. These findings underscore the need to adjust interpretations of treadmill gait clinical tests in middle-aged Uruguayan adults (45 to 65 years).
A avaliação da marcha na esteira pode ser relevante para a tomada de decisões clínicas. No entanto, fatores demográficos como idade e IMC podem alterar a interpretação dos resultados. Nosso objetivo foi obter variáveis espaço-temporais, energéticas e custo de transporte durante a velocidade de caminhada autoselecionada na esteira para uma amostra representativa de adultos uruguaios (n = 28) e avaliar se diferentes faixas etárias e IMC podem ser fatores a serem considerados em testes clínicos que envolvam essas variáveis. Dezessete homens e onze mulheres participaram (39,3 ± 14,8 anos, 75,9 ± 12,5 kg, 1,74 ± 0,09 m, IMC 25,2 ± 4,06). Foi realizada uma reconstrução tridimensional do movimento sincronizada com o consumo de energia. Foram obtidos valores de referência e os dados foram comparados usando testes t (p≤0,05), após agrupar os participantes por IMC e faixa etária. Os resultados revelaram discrepâncias significativas nas medidas espaço-temporais e energéticas dos adultos uruguaios ao caminhar na esteira, em comparação com a literatura. A marcha diferiu entre adultos jovens e de meia-idade em sua velocidade autoselecionada (p=0,03), comprimento da passada (p=0,01), trabalho mecânico externo (<0,001) e recuperação de energia mecânica (0,009), destacando a importância de considerar a idade em avaliações clínicas. O IMC não influenciou significativamente essas variáveis. Esses achados destacam a necessidade de ajustar as interpretações dos testes clínicos de marcha na esteira em adultos uruguaios de meia- idade (45 a 65 anos).
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Body Composition/physiology , Walking/physiology , Exercise Test/statistics & numerical data , Body Mass Index , Age DistributionABSTRACT
Aims: This study aims to comprehensively examine the surface morphology of fiber posts after undergoing various disinfection methods, utilizing scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Materials and Methods: Twenty-one fiber posts were randomly allocated into seven experimental groups, each consisting of three samples. The disinfection methods employed were as follows: GC - no disinfection treatment; GAL - immersion in 70% alcohol, following the manufacturer's recommended protocol; GHP - soaking in 2.5% sodium hypochlorite for a duration of 10 minutes; GCL - soaking in 2% chlorhexidine gluconate for a period of five minutes; GAC - 30-second etching with 35% phosphoric acid; GPH - soaking in 10% hydrogen peroxide for a duration of 20 minutes; and GSL - autoclave sterilization. Following the disinfection procedures, SEM was employed to scrutinize the surface topography of the posts, while EDX was utilized to identify the chemical elements present on the sample surfaces. Subsequently, a descriptive analysis was conducted on the SEM images and EDX data. Results: SEM analysis revealed that all groups exhibited regions with epoxy resin-coated fibers alongside sections with exposed glass fibers. Analysis of the EDX data indicated that there were no significant differences in the predominant chemical elements across the groups. Carbon (C) and oxygen (O) registered the highest peaks, followed by silicon (Si), zirconium (Zr), sodium (Na), aluminum (Al), and calcium (Ca). Conclusions: The disinfection methods under investigation did not induce substantial alterations in the surface morphology of the fiber posts.
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Introduction: In areas with limited access to healthcare systems, Resting Energy Expenditure (REE) estimation is performed using predictive equations to calculate an individual's caloric requirement. One problem is that these equations were validated in populations with different characteristics from those in Latin America, such as race, height, or body mass, leading to potential errors in the prediction of this parameter. Objective: To determine the REE using predictive formulas compared with bioimpedance in Peruvians. Materials and methods: A comparative analytical cross-sectional study with secondary database analysis of the CRONICAS cohort. Results: we worked with a total of 666 subjects. The Mjeor equation was the one with the highest rating of 0.95, a lower mean absolute percentage error (MAPE) of 4.69%, and equivalence was found with the REE values. In the multiple regression, it was observed that the Mjeor equation was the one that least overestimated the REE, increasing 0.77 Kcal/day (95% CI: 0.769-0.814; p<0.001) for each point that increased the REE determined by bioimpedance. The strength of association between Mjeor and bioimpedance was 0.9037. Furthermore, in the regression of the data (weight, height, age) in the Mjeor equation it was observed that the coefficients obtained were the same as those used in the original equation. Conclusions: The Mjeor equation seems to be the most adequate to estimate the REE in the Peruvian population. Future prospective studies should confirm the usefulness of this formula with potential utility in primary health care(AU)
Introducción: En zonas con acceso limitado a sistemas de salud, la estimación del Gasto Energético en Reposo (GER) se realiza utilizando ecuaciones predictivas para calcular el requerimiento calórico de un individuo. Uno de los problemas es que estas ecuaciones fueron validadas en poblaciones con características diferentes a las latinoamericanas, como raza, talla o masa corporal, lo que conlleva a potenciales errores en la predicción de este parámetro. Objetivo: Determinar el GER mediante fórmulas predictivas comparadas con la bioimpedancia en peruanos. Materiales y métodos: Estudio transversal analítico comparativo con análisis secundario de base de datos de la cohorte CRONICAS. Resultados: Se trabajó con un total de 666 sujetos. La ecuación de Mjeor fue la que obtuvo la puntuación más alta de 0,95, un error medio porcentual absoluto (MAPE) inferior de 4,69%, y se encontró equivalencia con los valores del GER. En la regresión múltiple, se observó que la ecuación de Mjeor fue la que menos sobreestimó el GER, aumentando 0,77 Kcal/día (IC 95%: 0,769-0,814; p<0,001) por cada punto que aumentaba el GER determinado por bioimpedancia. La fuerza de asociación entre Mjeor y bioimpedancia fue de 0,9037. Además, en la regresión de los datos (peso, talla, edad) de la ecuación de Mjeor se observó que los coeficientes obtenidos eran los mismos que los utilizados en la ecuación original. Conclusiones: La ecuación de Mjeor parece ser la más adecuada para estimar el GER en la población peruana. Futuros estudios prospectivos deberán confirmar la utilidad de esta fórmula para su potencial utilidad en la atención primaria de salud(AU)
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Humans , Male , Female , Adolescent , Adult , Middle Aged , Cross-Sectional Studies , Electric Impedance , Energy Metabolism , Forecasting , Body Mass Index , Racial Groups , Diet , ObesityABSTRACT
La sepsis es un problema global de salud y la progresión hacia el shock séptico se asocia con un incremento marcado de la morbimortalidad. En este escenario, el aumento del lactato plasmático demostró ser un indicador de gravedad y un predictor de mortalidad, y suele interpretarse casi exclusivamente como marcador de baja perfusión tisular. Sin embargo, últimamente se produjo un cambio de paradigma en la exégesis del metabolismo y propiedades biológicas del lactato. En efecto, la adaptación metabólica al estrés, aun con adecuado aporte de oxígeno, puede justificar la elevación del lactato circulante. Asimismo, otras consecuencias fisiopatológicas de la sepsis, como la disfunción mitocondrial, se asocian con el desarrollo de hiperlactatemia sin que necesariamente se acompañen de baja perfusión tisular. Interpretar el origen y la función del lactato puede resultar de suma utilidad clínica en la sepsis, especialmente cuando sus niveles circulantes fundamentan las medidas de reanimación.
Sepsis is a global health problem; progression to septic shock is associated with a marked increase in morbidity and mortality. In this setting, increased plasma lactate levels demonstrated to be an indicator of severity and a predictor of mortality, and are usually interpreted almost exclusively as a marker of low tissue perfusion. However, a recent paradigm shift has occurred in the exegesis of lactate metabolism and its biological properties. Indeed, metabolic adaptation to stress, even with an adequate oxygen supply, may account for high circulating lactate levels. Likewise, other pathophysiological consequences of sepsis, such as mitochondrial dysfunction, are associated with the development of hyperlactatemia, which is not necessarily accompanied by low tissue perfusion. Interpreting the origin and function of lactate may be of great clinical utility in sepsis, especially when circulating lactate levels are the basis for resuscitative measures.
Subject(s)
Humans , Shock, Septic , Sepsis/diagnosis , Hyperlactatemia/complications , Hyperlactatemia/etiology , Lactic Acid/metabolismABSTRACT
SUMMARY: Diabetes is a form of endocrine disease. Dual-energy X-ray Absorptiometry (DXA) provides a detailed view of the body composition to find out what makes people with diabetes different from those with other diseases. We scanned 371 patients with DXA to analyze their body composition parameters. Three hundreds and seventy one patients (178 women/193 men), who with different diseases, with a mean±SD Body Mass Index (BMI) of 25.32±8.3 kg/m2 were included. The body composition of 371 patients was assessed. Bone Mineral Density (BMD), Fat Weight, Lean Weight, waist-to-hip ratio, Lean Mass Index (LMI), Fat Mass Index (FMI), the relationship between Fat percentage and BMI were analyzed. The 371 patients included 156 diabetics and 215 non-diabetics. Non-diabetic patients also included 5 obesity patients, 9 patients with fatty liver, 39 patients with hypertension, 22 patients with hyperlipidemia, 18 patients with cardiovascular disease, 11 patients with chest and lung disease, 4 patients with chronic disease, 14 patients with brain disease and 93 patients with other diseases. Among 156 diabetic patients, 129 had VAT > 100 cm2 and 27 had VAT ≤100 cm2. The lean weight (LW) of male diabetic patients was significantly higher than that of female diabetic patients. The fat weight (FW) of female patients with diabetes was significantly higher than that of male patients. The waist-hip ratio (WHR) was 1.37 ± 0.25 in male diabetic patients and 1.18 ± 0.21 in female diabetic patients. Among the 215 non-diabetic patients, the obese and fatty liver patients, which the weight (WT) (obesity: 83.87 ± 8.34 kg fat liver: 85.64±28.60 kg), FW (obesity: 28.56 ± 4.18 kg fat liver: 28.61 ± 10.79 kg), LW (obesity: 52.62 ± 9.64 kg fat liver: 54.29±17.58 kg), BMI (obesity: 28.76 ± 1.88 kg/m2 fat liver: 29.10 ± 5.95 kg/m2), was much higher than other patients. Diabetes patients had less fat mass than non- diabetic patients; the difference was around 2 kg. BMI is also a modest number. BMD doesn't differ all that much. Non-diabetic patients with fatty liver obesity and cardiovascular disease had higher fat mass and BMI than patients with other illnesses. Body composition can provide precise information on the makeup of different body areas, but further in-depth exams are required to ascertain the body's endocrine profile.
La diabetes es una enfermedad endocrina. La absorciometría de rayos X de energía dual (DXA) proporciona una vista detallada de la composición corporal para descubrir qué diferencia a las personas con diabetes de aquellas con otras enfermedades. Escaneamos a 371 pacientes con DXA para analizar sus parámetros de composición corporal. Se incluyeron 371 pacientes (178 mujeres/193 hombres), con diferentes enfermedades, con un Índice de Masa Corporal (IMC) medio ± DE de 25,32 ± 8,3 kg/m2. Se evaluó la composición corporal de 371 pacientes. Se analizaron la densidad mineral ósea (DMO), el peso graso, el peso magro, la relación cintura-cadera, el índice de masa magra (LMI), el índice de masa grasa (FMI), y la relación entre el porcentaje de grasa y el IMC. De los 371 pacientes 156 eran diabéticos y 215 no diabéticos. Los pacientes no diabéticos también incluyeron 5 con obesidad, 9 con hígado graso, 39 con hipertensión, 22 con hiperlipidemia, 18 con enfermedad cardiovascular, 11 con enfermedad torácica y pulmonar, 4 con enfermedad crónica, 14 con enfermedad cerebral y 93 pacientes con otras enfermedades. Entre los 156 pacientes diabéticos, 129 tenían un IVA > 100 cm2 y 27 tenían un IVA ≤100 cm2. El peso magro (PV) de los hombres diabéticos fue significativamente mayor que el de las mujeres diabéticas. El peso graso (FW) de las mujeres diabéticas fue significativamente mayor que el de los hombres diabéticos. El índice cintura-cadera (ICC) fue de 1,37 ± 0,25 en hombres diabéticos y de 1,18 ± 0,21 en mujeres diabéticas. Entre los 215 pacientes no diabéticos, los pacientes obesos y con hígado graso, cuyo peso (WT) (obesidad: 83,87 ± 8,34 kg hígado graso: 85,64 ± 28,60 kg), FW (obesidad: 28,56 ± 4,18 kg hígado graso: 28,61 ± 10,79 kg), PV (obesidad: 52,62 ± 9,64 kg, hígado graso: 54,29 ± 17,58 kg), IMC (obesidad: 28,76 ± 1,88 kg/m2, hígado graso: 29,10 ± 5,95 kg/m2), fue mucho mayor que otros pacientes. Los pacientes diabéticos tenían menos masa grasa que los pacientes no diabéticos; la diferencia fue de alrededor de 2 kg. La DMO no difiere mucho. Los pacientes no diabéticos con obesidad debido al hígado graso y enfermedades cardiovasculares tenían mayor masa grasa e IMC que los pacientes con otras enfermedades. La composición corporal puede proporcionar información precisa sobre la composición de diferentes áreas del cuerpo, pero se requieren exámenes más profundos para determinar el perfil endocrino del cuerpo.
Subject(s)
Humans , Male , Female , Body Composition , Absorptiometry, Photon , Diabetes Mellitus , Bone Density , Adipose TissueABSTRACT
Energy drinks are nonalcoholic beverages whose main ingredients are sugar, taurine, and caffeine. The consumption of energy drinks is increasing worldwide, but only a few conflicting studies have investigated the vascular effects of energy drinks in young adults. The aim of this study was to evaluate microvascular reactivity before and after energy drinks consumption in young healthy male volunteers. This was a cross-sectional prospective study. Microvascular reactivity signals were evaluated in the skin of the forearm using laser speckle contrast imaging with acetylcholine (ACh) iontophoresis before and 90 and 180 min after the randomized consumption of one ED or the same volume of water (control), followed by a postocclusive reactive hyperemia (PORH) test. Thirty-two volunteers were evaluated (age: 25.4±4.3 years). Energy drink consumption prevented the rest-induced reduction in cutaneous vascular conductance over time that was observed in the control group. In the control group, there were significant reductions in microvascular vasodilation at 90 and 180 min compared to baseline (P=0.004), but this was not the case in the energy drink group (P=0.76). Our results demonstrated that the reduction in microvascular conductance associated with prolonged immobility can be prevented by the consumption of one energy drink, highlighting the vasodilator effects of this beverage in young individuals at rest. The between-study variability in terms of the brand of energy drinks and the ingested volume, as well as the method of vascular evaluation and the inclusion criteria, may explain the discrepancies among previous studies on the vascular effects of energy drinks.
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Osteogenesis imperfecta（OI）is a hereditary connective tissue disease，and roughly 85% of the patients are caused by heterozygous mutations in COL1A1 and COL1A2，the coding genes of type Ⅰcollagen. Primary symptomatic manifestations of OI are low bone mass，frequent fractures and skeletal deformity，and other symptoms include blue sclera，dentinogenesis imperfecta，hyperlaxity of joint and ligaments，short stature and hearing impairment. Some patients may have muscle weakness，obesity and other symptoms，and the systemic low-grade inflammation and changes in bone microenvironment caused by obesity may have more negative effects on OI bones. The occurrence of obesity in OI patients may be related to energy metabolism abnormalities caused by multiple factors such as reduced activity，abnormal muscle fat metabolism，and diverse genotypes. Currently，there is a lack of large sample data on the incidence of obesity，and exploring the mechanism of skeletal-muscle interaction and energy metabolism regulation is of great significance for OI related obesity prevention and treatment.
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Objective To explore the diagnostic value of energy spectrum CT quantitative parameters combined with serum thy-roid stimulating hormone receptor-messenger ribonucleic acid(TSHR-mRNA)for papillary thyroid microcarcinoma(PTMC).Methods A total of 105 patients with thyroid micronodules confirmed by surgery and pathology were collected,61 of whom were PTMC(PTMC group),and 44 patients with micronodular goiter(MNG)(MNG group).Energy spectrum CT quantitative parameters and serum TSHR-mRNA expression were compared between the two groups.The diagnostic value of energy spectrum CT quantitative parame-ters alone and combined with serum TSHR-mRNA for PTMC was analyzed by receiver operating characteristic(ROC)curve.Results The iodine concentration and slope of energy spectrum CT quantitative parameters between PTMC group and MNG group were signifi-cantly different in plain scan,arterial and venous phases(P＜0.05).The mean serum TSHR-mRNA expression in the PTMC group was higher than that in MNG group(P＜0.05).The area under the curve(AUC)for diagnosing PTMC using quantitative parame-ters of energy spectrum CT combined with serum TSHR-mRNA was 0.913,and the accuracy,sensitivity,and negative predictive value of diagnosing PTMC were significantly higher than those of quantitative parameters of energy spectrum CT or serum TSHR-mRNA(P＜0.05).Conclusion Both energy spectrum CT quantitative parameters and serum TSHR-mRNA can be used to diagnose PTMC alone,and the combination of both is more accurately.
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Objective To investigate the feasibility of energy spectrum CT material separation technology for quantitative evaluation of nonalcoholic fatty liver patients,to compare the accuracy of this method with the conventional liver/spleen CT ratio for grading liver fat content.Methods Sixty patients diagnosed with nonalcoholic fatty liver and 20 healthy volunteers were chosen to undergo liver MR multi-echo(ME)Dixon and energy spectrum CT scans.The proton density fat fraction(PDFF),fat concentration(FC),and liver/spleen CT ratio were then measured for each participant.According to PDFF,nonalcoholic fatty liver patients were divided into mild fatty liver group,moderate fatty liver group,and severe fatty liver group.Results With the increase in PDFF,FC increased and the liver/spleen CT ratio decreased.The difference between FC groups in normal,mild,moderate and severe fatty liver groups was statistically significant(P<0.05),while the difference between the liver/spleen CT ratio of normal group and mild fatty liver group was not statistically significant(P>0.05).The receiver operating characteristic(ROC)curve analysis showed that when the critical value of FC was 351.19 mg/mL,the sensitivity,specificity and area under the curve for normal group and fatty liver group were 0.95,0.1 and 0.99,respectively.Conclusion The energy spectrum CT material separation technology has a good correlation between the fat content measured by the MR ME Dixon,which is superior to the fat content measured by the liver/spleen CT ratio.For patients with nonalcoholic fatty liver,FC in energy spectrum CT has high accuracy in differentiating normal and mild fatty liver.
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Objective To investigate the application value of quantitative analysis of the energy spectrum CT in the diagnosis and differential diagnosis of pulmonary mucinous adenocarcinoma and non-mucinous adenocarcinoma.Methods A retrospective analysis was conducted on the energy spectrum CT parameters of 12 cases of pulmonary mucinous adenocarcinoma and 24 cases of non-mucinous adenocarcinoma confirmed by surgery and pathology.Results There were significant differences between pulmonary mucinous adenocarcinoma and non-mucinous adenocarcinoma in 40-60 keV in plain scan,50-100 keV in arterial phase,40-140 keV CT value in venous phase and delayed phase,effective atomic number in plain scan,iodine concentration in venous phase and delayed phase(P<0.05).Conclusion The analysis of parameters of energy spectrum CT can be used for qualitative diagnosis and differential diagnosis of pulmonary mucinous adenocarcinoma and non-mucinous adenocarcinoma.
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Objective To evaluate the accuracy of bioelectrical impedance analysis(BIA)in measurement of appendicular skeletal muscle mass(ASM)of adults.Methods A total of 836 adults aged 18-42 years were recruited in Guangzhou using a convenient sampling method from April 2021 to September 2022.ASM was measured using BIA and Dual-energy X-ray absorptiometry(DXA).Using DXA as the standard method,the consistency between the BIA and DXA measurements was evaluated by intra-class correlation coefficients(ICCs)and Bland-Altman analysis in logarithmically transformed data,in order to evaluate the accuracy of BIA in ASM measurement.Receiver operating characteristic curve was plotted to evaluate the diagnostic value of BIA for screening low muscle mass.Results A total of 774 individuals were included for analysis finally.ICCs for ASM measured by BIA and DXA were 0.774 and 0.667 in males and females,respectively.Mean ratios(limits of Agreement)of ASM were 0.94(0.80-1.10)and 0.91(0.78-1.05)in males and females,respectively.Area under curve of BIA for screening low muscle mass were 0.91 and 0.94 in males and females,respectively.The optimal cut-off values of Z-score by BIA for males and females were-0.57 and-0.66,respectively.Sensitivity and specificity for males were 82.5%and 86.0%,while being 86.8%and 93.8%,for females.Conclusion BIA shows a moderate consistency with DXA for measuring ASM in adults.Furthermore,BIA yields a good diagnostic value in identifying low muscle mass in adults aged 18-42 years.
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BACKGROUND:At present,the traditional powder sintering method is easy to introduce impurities in the process of preparing porous titanium,and the manufacturing of porous titanium still faces two major problems:impurity pollution and difficult control of the material forming process. OBJECTIVE:To prepare pure porous titanium with certain porosity,and analyze the microstructure evolution and properties of the porous titanium. METHODS:Porous titanium was prepared at a low energy density by selective laser melting technology.The parameter range of porous titanium with large porosity was obtained by measuring the porosity of the formed specimen,and the evolution of the microstructure and mechanical properties of the specimen in the range were analyzed. RESULTS AND CONCLUSION:(1)With the increase in energy density,the porosity of the porous titanium specimen decreased gradually.When the energy density was between 10.61 and 27.78 J/mm3,porous titanium with a porosity of 11.23%-33.67%could be formed.When the energy density was between 27.78-37.88 J/mm3,the forming parts were relatively dense.(2)The phase composition of porous titanium formed was mainly α titanium.With the increase in energy density,the porosity gradually decreased,and the pore morphology changed from irregularly connected pores to closed nearly spherical pores.The powder particles changed from a slightly sintered neck to a continuous fuse.The CT scan results revealed that there were a large number of connected pores in the forming specimen with a large specific surface area and the pore radius was roughly distributed between 2-6 μm at the energy density of 10.61 J/mm3.Simultaneously,porous titanium with compressive strength of 188-1 000 MPa could be obtained at the energy density of 10.61-27.78 J/mm3,which could meet the requirements of biomedical applications.(3)These results have confirmed that the selective laser melting technology can overcome the problems of impurity pollution and long manufacturing cycle caused by the traditional preparation process,and provide an effective solution for the preparation of porous titanium with excellent mechanical properties.
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BACKGROUND:Patients with severe lumbar degenerative disease may have their bone mineral density incorrectly raised by dual-energy X-ray absorptiometry.While lumbar cancellous bone Hounsfield unit value can assist dual-energy X-ray absorptiometry in reducing osteoporosis misdiagnosis. OBJECTIVE:To identify osteoporosis in woman patients with lumbar degenerative diseases using lumbar CT scans. METHODS:Bone mineral density test results and lumbar CT data of 192 women patients who were treated at the Department of Spine Surgery,Sixth Affiliated Hospital of Xinjiang Medical University were retrospectively reviewed.All patients were divided into a degeneration group(n=107)and a control group(n=85)according to the criteria of severity of vertebral degeneration as assessed on CT of the lumbar spine.The CT value of axial cancellous bone of L1 vertebral body was measured in the two groups.The T score and bone mineral density of the hip and L2-L4 were recorded.According to previously published studies,osteoporosis was diagnosed at L1 vertebral CT values≤110.The prevalence of osteoporosis diagnosed by dual-energy X-ray absorptiometry and CT values was compared between the two groups. RESULTS AND CONCLUSION:(1)CT values were significantly and positively correlated with T scores and mean bone mineral density of the L2-L4 vertebrae in both groups(P<0.001),while the correlation was higher in the control group.(2)Lumbar T scores and bone mineral density values were significantly higher in the degeneration group than those in the control group(P<0.05)and CT values were significantly lower in the degeneration group than that in the control group(P = 0.001).Hip T scores and bone mineral density were not significantly different in the two groups.(3)The prevalence of osteoporosis diagnosed by CT thresholds was higher in all patients than that diagnosed by T values(51.0%and 42.7%).(4)The prevalence of osteoporosis diagnosed by CT values was as high as 23.6%in the 110 patients diagnosed with non-osteoporosis by dual energy X-ray absorptiometry in both groups,and was higher in the degeneration group than that in the control group(31.7%and 14.0%,respectively).(5)The prevalence of missed osteoporosis was as high as 38.6%(27/70)of non-osteoporosis patients diagnosed by dual-energy X-ray absorptiometry of the lumbar spine in the degeneration group compared to 19.6%(11/56)in the control group.(6)It is concluded that osteoporosis is common in female patients with lumbar degenerative diseases aged≥50 years.Measurement of lumbar cancellous bone CT values may be a useful complementary method for diagnosing osteoporosis in patients with lumbar degenerative diseases,especially in patients with severe degenerative lumbar degenerative diseases where more missed osteoporosis patients can be identified.
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BACKGROUND:In recent years,studies have shown that obesity is closely related to chronic inflammation.Due to excessive energy intake,inflammatory macrophage infiltration and inflammatory response occur in visceral adipose tissue,which is crucial for the regulation of adipose tissue fibrosis. OBJECTIVE:To summarize the molecular mechanism of inflammation-related signals involved in the regulation of adipose tissue fibrosis and to provide reference for the treatment of adipose tissue fibrosis and related metabolic diseases through anti-inflammatory pathways. METHODS:Relevant documents were retrieved from CNKI and PubMed,and the Chinese and English search words were"inflammation,inflammatory factors,inflammatory signals,lip fibrosis,adipose fibrosis,adipose tissue fibrosis"respectively.The search period was from January 2003 to December 2022.Finally,52 documents meeting the criteria were included for review. RESULTS AND CONCLUSION:During obesity,visceral adipose tissue expands through adipocyte proliferation and hypertrophy to store excess energy,and defects caused by remodeling or functional changes mainly include impaired angiogenesis,adipocyte apoptosis promoted by white adipose tissue hypoxia,macrophage infiltration,and adipocyte fibrosis.Adipose tissue fibrosis has adverse effects on the natural growth of adipose cells.The factors that trigger chronic inflammation of adipose tissue include a variety of signal stimuli,such as adipocyte death caused by hypoxia,mechanical signal transduction caused by extracellular matrix remodeling and lipogenic factor imbalance.Inflammatory factors such as interleukin-1β,tumor necrosis factor-α,C-type lectins and adiponectin secreted by adipocytes and other inflammatory signaling pathways such as nuclear factor-κB,transforming growth factor-β/Smad and MAPK jointly regulate the process of adipose tissue fibrosis.
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BACKGROUND:There is still controversy whether human bone marrow mesenchymal stem cells can maintain their biological characteristics,energy metabolism patterns,and multidirectional differentiation potential after long-term expression in vitro.Further comprehensive and systematic research is needed. OBJECTIVE:To evaluate the effects of long-term expansion in vitro on the biological characteristics of mesenchymal stem cells. METHODS:Human bone marrow mesenchymal stem cells cultured to passage 5,10,and 15 in vitro.MTT assay was used to detect cell proliferation ability.Flow cytometry was used to detect cell cycle.The multi-differentiation potential of mesenchymal stem cells was detected by inducing to adipogenic,osteogenic and chondrogenic differentiation.Cell migration and invasion abilities were detected by scratch test and Transwell assay.The mitochondrial oxidative phosphorylation and glycolysis function were analyzed using energy metabolism analyzer.The cell senescence was detected by senescence-associated β-galactosidase staining.The expression levels of p21,p16,and p53 proteins were detected by western blot assay. RESULTS AND CONCLUSION:Bone marrow mesenchymal stem cells at passages 5,10,and 15 grew adherently;the volume of passage 15 mesenchymal stem cells increased and its proliferation ability decreased;the percentage of S-phase cells decreased(P<0.05).With the increase of culture passages,the migration and invasion abilities decreased gradually(P<0.05).There was no significant difference in the differentiation potential,demonstrated by adipogenic,osteogenic and chondrogenesis induction.The ability of oxidative phosphorylation of mitochondria and glycolysis decreased gradually(P<0.05).The number of senescence-associated β-galactosidase-positive cells increased with the increase of passages(P<0.05),and the expression of senescence protein p21,p16,and p53 increased gradually(P<0.05).The results indicated that the biological characterization of mesenchymal stem cells changed after long-term in vitro expansion.Mesenchymal stem cells cultured over 10 passages may have a reduced activity due to increasing senescence.Therefore,bone marrow mesenchymal stem cells cultured less than 10 passages are suitable for clinical research/therapy.
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BACKGROUND:The development of tissues and organs in the body is a precise and autonomously regulated process,and the function of biomechanical factors at this macroscale is a basic scientific question worth exploring. OBJECTIVE:To investigate the roles of cell mechanics in morphogenesis of the lobular organoid of 3D Madin-Darby canine kidney(MDCK). METHODS:The formation of MDCK lobular organoid was visualized by fluorescence resonance energy transfer technology,and the influence of different cellular mechanical signals and extracellular matrix environment on lobular organoid formation and corresponding changes in extracellular regulated protein kinases(ERK)activity were examined. RESULTS AND CONCLUSION:(1)Inhibition of ERK signaling pathway can inhibit the growth of MDCK lobular organoid.(2)Inhibition of cell contractile force signals such as ROCK pathway and Myosin Ⅱ activity,reduced ERK activity and lobular organoid size.(3)Selective inhibition of calcium channels in plasma membrane and endoplasmic reticulum led to reduced ERK activity and lobular organoid growth.(4)By inhibiting the mechanically-sensitive receptor Piezo ion channel or integrin signal on the cell membrane,the lobular organoid became smaller or MDCK cells could not generate tissue morphology.(5)Extracellular matrix compositions affected the morphogenesis of lobular organoid.The addition of type I collagen in Matrigel changed the lobular organoid to elongated shape.(6)The results of this study preliminarily show that mechanical signals in the cells and extracellular matrix environment play an important role in culturing MDCK lobular organoid,and provides certain molecular mechanisms.
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BACKGROUND:Critical energy release rate is a global fracture parameter that could be measured during the failing process,and its value may change under different failure modes even in the same structure. OBJECTIVE:To propose an approach to predict the critical energy release rate in the femoral cortical bone structure under different failure modes. METHODS:Three-point bending and axial compression experiments and the corresponding fracture simulations were performed on the rat femoral cortical bone structures.Different critical energy release rates were repeatedly assigned to the models to perform fracture simulation,and the predicted load-displacement curves in each simulation were compared with the experimental data to back-calculate the critical energy release rate.The successful fit was that the differences in the fracture parameters between the predicted and experimental results were less than 5%. RESULTS AND CONCLUSION:(1)The results showed that the cortical bone structure occurred tensile open failure under three-point bending load,and the predicted critical energy release rate was 0.16 N/mm.(2)The same cortical bone structure occurred shear open failure under axial compression load,and the predicted critical energy release rate was 0.12 N/mm,which indicates that the critical energy release rate of the same cortical bone structure under different failure modes was different.(3)A comprehensive analysis from the perspectives of material mechanical properties and damage mechanism was conducted to reveal the reasons for the differences in the critical energy release rate in the cortical bone structure under different failure modes,which provided a theoretical basis for the measurement of the energy release rate and the accurate fracture simulation.
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Objective To study the effect of dual-mediated brain targeting liposomes(RVGPR9-SSL)as delivery vehicles on the blood brain barrier(BBB)permeability of doxorubicin(DOX),providing a new strategy for brain drug delivery.Methods The dual-mediated brain targeting liposomes(RVGPR9-SSL)were prepared by thin film dispersion/leading compound method.And the chemo-therapeutic drug DOX was encapsulated in RVGPR9-SSL(DOX@RVGPR9-SSL).Brain microvascular endothelial cells(BMVEC)were cultured and used to construct in vitro BBB models.The BBB model was then evaluated by a 4h leakage test,transmembrane resist-ance value(TEER)measurement,and tight junctions between cells observed by scanning transmission electron microscope(SEM).After the successful construction of the BBB model,the integrity of RVGPR9-SSL after crossing the BBB was investigated by confocal laser scanning microscopy using fluorescence a resonance energy transfer(FRET)pair.The effect of RVGPR9-SSL administration on BBB in-tegrity was evaluated by comparative analysis of BBB morphology and TEER values before and after liposome administration.The BBB per-meability of DOX@RVGPR9-SSL was investigated by fluorescence spectrophotometry.Results The encapsulation efficiency of DOX@RVGPR9-SSL was 97.25％.The TEER values of the constructed BBB model were all greater than 200Ω·cm2,and it was observed by SEM that the BMVEC cells were closely arranged and there were obvious tight junctions,indicating that the in vitro BBB model was suc-cessfully established and could be used for the investigation of BBB permeability.The 4h BBB cumulative permeability of DOX@RVGPR9-SSL was greater than 10％,which was significantly higher than that of free DOX.And both BBB and liposomes maintained good integrity after administration.Conclusion RVGPR9-SSL can significantly improve the BBB permeability of DOX,indicating that it is a very promising brain drug delivery vehicle.
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AIM:To investigate the effect of spermidine(SPD)on pressure overload-induced cardiac hyper-trophy and heart failure model in mice and its underlying mechanisms.METHODS:(1)Eight-week-old male C57BL/6J mice were randomly divided into 4 groups:sham group,sham+SPD group,transverse aortic constriction(TAC)group,and TAC+SPD group.After TAC,the mice in sham+SPD group and TAC+SPD group were fed with 3 mmol/L SPD via drinking water,and the mice in other groups were fed with normal water.Western blot was used to detect the protein ex-pression levels of silent information regulator 6(SIRT6),peroxisome proliferator-activated receptor γ coactivator-1(PGC-1)and mitofusin 2(MFN2).Adult mouse cardiomyocytes were isolated to detect cell length and width.Wheat germ agglu-tinin staining was used to detect the cardiac cell size.Masson staining was used to detect the extent of fibrosis.Echocar-diography was used to detect cardiac function and myocardial hypertrophy.Transmission electron microscopy was used to analyze mitochondrial morphology.Oxygraph-2k high-resolution respirometer was used to detect cardiac mitochondrial oxy-gen consumption.(2)In vitro,primary rat ventricular cardiomyocytes were cultured and treated with angiotensin II(Ang II;1 μmol/L)to construct a hypertrophy model of cardiomyocytes.These cardiomyocytes were divided into control(Con)group,Con+SPD(1 mmol/L)group,Ang II group,Ang II+SPD group and Ang II+SPD+SIRT6 siRNA(siSIRT6)group.Confocal microscopy was used to detect cardiomyocytes area and mitochondrial.RESULTS:(1)Compared with sham group,cardiac function of the mice in TAC group was significantly decreased(P＜0.05),the degree of myocardial hyper-trophy was significantly increased(P＜0.05),and the expression levels of SIRT6,PGC-1 and MFN2 in the myocardial tis-sue were significantly decreased(P＜0.05).Compared with TAC group,the expression levels of SIRT6,PGC-1 and MFN2 in mouse myocardial tissues of TAC+SPD group were significantly increased(P＜0.05),pathological myocardial hy-pertrophy was reduced(P＜0.05),the numbers of mitochondria and mitochondrial cristae were increased(P＜0.05),mito-chondrial function was restored(P＜0.05),myocardial fibrosis was alleviated(P＜0.05),and cardiac function was im-proved(P＜0.05).(2)In vitro,compared with Con group,the expression levels of SIRT6,PGC-1 and MFN2 in cardio-myocytes of Ang II group were decreased(P＜0.05),and the degree of cardiomyocyte hypertrophy was significantly in-creased(P＜0.05).Treatment with SPD increased the expression levels of SIRT6,PGC-1 and MFN2 in cardiomyocytes of Ang II group(P＜0.05),reversed myocardial hypertrophy and improved mitochondrial dynamics(P＜0.05).Compared with Ang II group,the expression levels of SIRT6,PGC-1 and MFN2 in Ang II+SPD+siSIRT6 group showed no significant changes,and the degree of cardiomyocyte hypertrophy and mitochondrial dynamics also had no statistically significant changes.CONCLUSION:Spermidine promotes the expression of SIRT6,PGC-1 and MFN2,thus improving mitochon-drial function,reducing myocardial hypertrophy and alleviating heart failure in mice with pressure overload.
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Objective To explore the mechanism of Nuanxinkang Powder(aka.NXK,composed of Ginseng Radix et Rhizoma Rubra and Ilex Pubescens Radix)on improving ventricular remodeling in post-infarction mice based on the"metabolic-inflammatory"network regulating macrophage polarization.Methods ①Thirty C57BL/6J male mice were randomly divided into three groups:sham-operation group,model group,and NXK group(1.65 g·kg-1),with 10 mice in each group;the mouse model of myocardial infarction was replicated using left anterior descending coronary artery ligation;and the drug was administered by gavage once a day for 4 consecutive weeks.Masson staining was used to detect collagen deposition in myocardial tissue;ultrasound was used to detect cardiac function in mice:left ventricular ejection fraction(LVEF),left ventricular anterior wall thickness at end-systole(LVAWS)and left ventricular anterior wall thickness at end-diastole(LVAWD);flow cytometry was used to detect distribution of cardiac macrophages in mice;qPCR was used to detect mRNA expressions of lactate dehydrogenase A(LDHA),carnitine palmitoyltransferase 1(CPT-1),glucose transport protein 4(GLUT4),isocitrate dehydrogenase(IDH),and succinate dehydrogenase(SDHa)in heart tissue.②NXK was given 1.15 g·kg-1 NXK suspension to rats by gavage twice a day for 5 consecutive days to prepare NXK-containing serum.Lipopolysaccharide(LPS)-induced RAW 264.7 cells were used to construct a pro-inflammatory macrophage model.The cells were grouped into the following groups:blank serum control group(medium containing 5%blank serum+5%fetal bovine serum),NXK drug-containing serum group(medium containing 5%NXK drug-containing serum+5%fetal bovine serum),lipopolysaccharide group(medium containing 5%blank serum+5%fetal bovine serum+200 μg·mL-1 lipopolysaccharide),NXK drug-containing serum+ lipopolysaccharide group(medium containing 5%NXK drug-containing serum+5%fetal bovine serum+200 μ g·mL-1 lipopolysaccharide),all the groups were intervened for 16 hours.Glycolysis stress test was used to detect the level of glycolysis in RAW 264.7 cells;qPCR was used to detect the mRNA expression of mitochondrial pyruvate carrier(MPC1)in RAW 264.7 cells;and MitoSox Red fluorescent staining was used to detect the level of oxidative stress damage in mitochondria of RAW 264.7 cells.Results ①Compared with the sham-operation group,the blue-stained area of cardiac collagen fibres in mice of the model group was significantly increased,accompanied by thinning of the ventricular wall and enlargement of the left ventricular cavity;cardiac function indexes,such as LVEF,LVAWS,LVAWD,etc.,were all significantly reduced(P＜0.01,P＜0.001);the mRNA expressions of LDHA and CPT-1 were significantly up-regulated in the cardiac tissues of mice(P＜0.05),and the mRNA expressions of GLUT4,IDH and SDHa were significantly down-regulated(P＜0.05,P＜0.01),and CD86 staining positive cell was significantly increased(P＜0.001).Compared with the model group,mice in the NXK group showed a significant decrease in cardiac collagen fiber deposition and an increase in the thickness of the ventricular wall;cardiac function indexes such as LVEF,LVAWS and LVAWD were significantly increased(P＜0.05,P＜0.01,P＜0.001);and the mRNA expressions of LDHA and CPT-1 in the cardiac tissues of the mice were significantly down-regulated(P＜0.01,P＜0.001),mRNA expressions of GLUT4,SDHa and IDH were significantly up-regulated(P＜0.01),and the number of CD86 positive cells was significantly reduced(P＜0.001).②Compared with the blank serum control group,the cytosolic glycolysis level and ROS level of macrophages in the NXK serum-containing group did not change significantly(P＞0.05),whereas the glycolysis level and ROS level of macrophages in the lipopolysaccharide group were significantly increased(P＜0.01),and the mRNA expression of MPC1 was significantly down-regulated(P＜0.001).Compared with the lipopolysaccharide group,the macrophage glycolysis level and ROS level were significantly reduced in the NXK serum-containing + lipopolysaccharide group(P＜0.05,P＜0.01),and mRNA expression of MPC1 was significantly up-regulated(P＜0.001).Conclusion NXK can reduce myocardial fibrosis and ventricular remodeling after myocardial infarction and improve cardiac function in mice,and its mechanism may be related to the down-regulation of mRNA expression of LDHA in cardiac tissues,the up-regulation of mRNA expression of GLUT4,the improvement of cardiac glucose uptake after myocardial infarction,the inhibition of pro-inflammatory macrophage glycolysis,the increase in the expressions of SDHa and IDH to alleviate the accumulation of succinate and citrate,and the reduction of reactive oxygen species(ROS)generation,thereby reducing pro-inflammatory macrophage hyperpolarisation.