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1.
Sensors (Basel) ; 22(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36433266

RESUMO

The implementation of robotic systems for minimally invasive surgery and medical procedures is an active topic of research in recent years. One of the most common procedures is the palpation of soft tissues to identify their mechanical characteristics. In particular, it is very useful to identify the tissue's stiffness or equivalently its elasticity coefficient. However, this identification relies on the existence of a force sensor or a tactile sensor mounted at the tip of the robot, as well as on measuring the robot velocity. For some applications it would be desirable to identify the biomechanical characteristics of soft tissues without the need for a force/tactile nor velocity sensors. An estimation of such quantities can be obtained by a model-based state observer for which the inputs are only the robot joint positions and its commanded joint torques. The estimated velocities and forces can then be employed for closed-loop force control, force reflection, and mechanical parameters estimation. In this work, a closed-loop force control is proposed based on the estimated contact forces to avoid any tissue damage. Then, the information from the estimated forces and velocities is used in a least squares estimator of the mechanical parameters. Moreover, the estimated biomechanical parameters are employed in a Bayesian classifier to provide further help for the physician to make a diagnosis. We have found that a combination of the parameters of both linear and nonlinear viscoelastic models provide better classification results: 0% misclassifications against 50% when using a linear model, and 3.12% when using only a nonlinear model, for the case in which the samples have very similar mechanical properties.


Assuntos
Robótica , Teorema de Bayes , Palpação , Tato , Procedimentos Cirúrgicos Minimamente Invasivos/métodos
2.
Sensors (Basel) ; 22(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35214234

RESUMO

Spinal mobility assessment is essential for the diagnostic of patients with ankylosing spondylitis. BASMI is a routine clinical evaluation of the spine; its measurements are made with goniometers and tape measures, implying systematic errors, subjectivity, and low sensitivity. Therefore, it is crucial to develop better mobility assessment methods. The design, implementation, and evaluation of a novel system for assessing the entire spine's motion are presented. It consists of 16 magnetic and inertial measurement units (MIMUs) communicated wirelessly with a computer. The system evaluates the patient's movements by implementing a sensor fusion of the triaxial gyroscope, accelerometer, and magnetometer signals using a Kalman filter. Fifteen healthy participants were assessed with the system through six movements involving the entire spine to calculate continuous kinematics and maximum range of motion (RoM). The intrarater reliability was computed over the observed RoM, showing excellent reliability levels (intraclass correlation >0.9) in five of the six movements. The results demonstrate the feasibility of the system for further clinical studies with patients. The system has the potential to improve the BASMI method. To the best of our knowledge, our system involves the highest number of sensors, thus providing more objective information than current similar systems.


Assuntos
Espondilite Anquilosante , Dispositivos Eletrônicos Vestíveis , Humanos , Fenômenos Magnéticos , Amplitude de Movimento Articular , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Coluna Vertebral , Espondilite Anquilosante/diagnóstico
3.
J Cancer Educ ; 37(5): 1433-1437, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33954934

RESUMO

The importance of self-breast examination to identify early signs of breast cancer has been widely discussed in scientific literature. We conducted a cross-sectional survey of women aged 18 years and over (n = 547) living in urban and rural areas in the State of Jalisco, Mexico. Survey questions included measures on knowledge, attitudes, behaviors, and practices related to self-breast examination. We compared these measures between women living in urban and rural areas and women aged 18-39 years and 40+ years. Using t-test, we tested the significance of these differentials. Our results indicate that there is no significant difference in knowledge, attitudes, behavior, and practices regarding self-breast examination between women living in urban and in rural areas of Jalisco. However, we found some difference in these measures between women in 18-39 years and 40+ years. While the State of Jalisco has taken significant steps toward promoting significance of cancer prevention, further attention to women in the older cohort is recommended.


Assuntos
Neoplasias da Mama , Conhecimentos, Atitudes e Prática em Saúde , Adolescente , Adulto , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/prevenção & controle , Autoexame de Mama , Estudos Transversais , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Mamografia , México
4.
Curr Microbiol ; 79(1): 17, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34905080

RESUMO

Azotobacter vinelandii is a motile bacterium that possesses an unusual pattern of peritrichous flagellation for members of the Pseudomonadaceae family. Unlike what has been reported for Pseudomonas spp. FleQ is not the master regulator of motility in A. vinelandii, this role is performed by FlhDC. Other factors involved in the regulation of motility are AlgU (σE) and CydR which act as negative regulators. In some members of the Enterobacteriaceae and Pseudomonadaceae families, the GacS/A-Rsm pathway is another important factor regulating motility. In the present study, the involvement of the GacS/A-Rsm pathway in regulating the motility of A. vinelandii was explored; we found that contrary to what has been reported for most of the strains studied of Pseudomonas species, GacS/A, through the Rsm system, positively controlled swimming motility. We show that the target of this regulation is the synthesis of flagella, which most likely occurs in an FlhDC-independent manner.


Assuntos
Azotobacter vinelandii , Azotobacter vinelandii/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Flagelos/metabolismo , Regulação Bacteriana da Expressão Gênica , Humanos
5.
Arch Microbiol ; 202(3): 579-589, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31741014

RESUMO

Azotobacter vineladii is a Gram-negative bacterium that produces alginate and poly-hydroxybutyrate (PHB), two polymers of biotechnological interest. This bacterium has the ability to form desiccation-resistant cysts. In the cyst the membrane phospholipids are replaced with a family of phenolic lipids called alkylresorcinols (ARs). The alginate, PHB, and ARs are controlled by the GacS/A two-component system and the small regulatory RNA (sRNA) RsmZ1, belonging to the Rsm (Csr) regulatory system. The Rsm (Csr) systems usually possess two or more sRNAs, in this regard A. vinelandii is the bacterium with the highest number of rsm-sRNAs. Originally, the presence of two sRNAs of the RsmY family (RsmY1 and RsmY2) was reported, but in a subsequent work it was suggested that they conformed to a single sRNA. In this work we provide genetic evidence confirming that rsmY1 and rsmY2 constitute a single gene. Also, it was established that rsmY mutation decreased alginate and ARs production, but did not affect the PHB synthesis. Transcriptional studies showed that rsmY has its higher expression during the stationary growth phase, and in the absence of RsmZ1, rsmY increases its transcription. Interestingly, rsmY expression was influenced by the carbon source, but its expression did not correlate with alginate production.


Assuntos
Alginatos/metabolismo , Azotobacter vinelandii/metabolismo , RNA Bacteriano/metabolismo , Resorcinóis/metabolismo , Azotobacter vinelandii/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Hidroxibutiratos/metabolismo , Mutação , RNA Bacteriano/genética
6.
J Fluoresc ; 30(2): 249-257, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31981011

RESUMO

Build-up of extracellular matrix in liver fibrosis results in changes on endogenous molecules expression that may be studied through the fluorescence characterization of ex vivo liver samples. To the best of our knowledge, no investigations have provided in-depth evidence and discussion on the changes of the endogenous fluorescence in ex vivo tissue due to the effects of the preservation media. In this work, we contrast and analyze the endogenous fluorescence from tryptophan, vitamin A, hydroxyproline and elastin cross-links potential biomarkers of the liver fibrosis, in in vivo measurements and liver samples preserved on formaldehyde, and two standard preservation media. As it is known, chemical changes in tissue, caused by formaldehyde fixation, alter the endogenous fluorescence spectra. We propose the use of phosphate-buffered saline (PBS), and Iscove's Modified Dulbecco's Medium (IMDM) to elude the fluorescence changes. PBS and IMDM showed to maintain the endogenous fluorescence characteristics similar to in vivo conditions. The results of this work point the way for a more reliable assessment of endogenous fluorescence in ex vivo hepatic studies.


Assuntos
Fluorescência , Hidroxiprolina/análise , Cirrose Hepática/diagnóstico , Triptofano/análise , Vitamina A/análise , Biomarcadores/análise , Meios de Cultura/química , Formaldeído , Humanos , Cirrose Hepática/induzido quimicamente , Fosfatos/química , Cloreto de Sódio/química , Espectrometria de Fluorescência
7.
Gac Med Mex ; 156(6): 532-538, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33877107

RESUMO

INTRODUCTION: In 2017, INEGI reported 84,142 deaths from malignant tumors in Mexico, while the World Health Organization indicated that the breast cancer mortality rate in 2018 was 11.2 per 100,000 women. OBJECTIVE: To show the trend of breast cancer mortality in women by municipality and health region of Jalisco in the 2010-2017 period. METHOD: Analytical study in which standardized mortality rates and relative risks of 3873 women were estimated by municipality of residence. Dispersion and central tendency spatial statistics were used. RESULTS: The mortality rate increased from 10.7 to 13.0 per 100,000 women in the 2010-2017 period. The highest values were found in the municipalities of Chapala (21.2) and Guadalajara (19.5); the mortality rate increased in four out of every 10 municipalities, and relative risk was up to 50-fold higher in some of the western and central Jalisco municipalities. CONCLUSIONS: An annual increase of 1.0 % was observed, although it was territorially differentiated. The results represent an opportunity to improve timely detection and diagnostic processes, as well as to guarantee the coverage of services. INTRODUCCIÓN: En 2017, el INEGI reportó 84 142 defunciones por tumores malignos en México y la Organización Mundial de la Salud indicó que la tasa de mortalidad por cáncer de mama en 2018 fue de 11.2 por 100 mil mujeres. OBJETIVO: Mostrar la tendencia de la mortalidad por cáncer de mama en mujeres según municipio y región sanitaria de Jalisco en el periodo 2010-2017. MÉTODO: Estudio analítico en el que se estimaron tasas estandarizadas de mortalidad y riesgos relativos por municipio de residencia de 3873 mujeres. Se utilizó estadística espacial de dispersión y tendencia central. RESULTADOS: La tasa de mortalidad aumentó de 10.7 a 13.0 por 100 mil mujeres en el periodo 2010-2017. Los valores más altos se encontraron en los municipios de Chapala (21.2) y Guadalajara (19.5), la tasa de mortalidad aumentó en cuatro de cada 10 municipios y el riesgo relativo fue hasta 50 veces mayor en algunos del occidente y centro de Jalisco. CONCLUSIONES: Se observó un incremento de 1.0 % anual, aunque territorialmente diferenciado. Los resultados representan una oportunidad para mejorar los procesos de detección y diagnóstico oportunos, así como para garantizar la cobertura de los servicios.


Assuntos
Neoplasias da Mama/mortalidade , Feminino , Humanos , México/epidemiologia , Mortalidade/tendências , Risco , Análise Espacial
8.
Rev Panam Salud Publica ; 43: e32, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31093256

RESUMO

OBJECTIVE: Estimate the probabilistic potential of introduction of the causative agent of influenza type A in Mexico, using geo-intelligence applied to health. METHODS: Ecological study of 1,973 influenza outbreaks with a high degree of pathogenicity, worldwide during the period 2014-2016. Geospatial modeling was developed with geo-intelligence tools such as spatial representation, a relational model, spatial characterization of the inoculum source with the maximum entropy model and the receiver operating characteristic (ROC) curve, using multicriteria spatial analysis. This was validated with the Moran index and geographically weighted regression. RESULTS: Isochrones (at an initial distance of 548 km) were estimated for health risks and their exponential growth; at the fourth isochrone, the east and west coasts of the United States of America and a part of Central America were identified as possible areas that favor the introduction of the pathogen. Also, a COR curve = 0.923 was obtained; two risk periods for introduction were identified (September-March and April-August, with north-south and south-north trajectories, respectively) with high positive autocorrelation for geospatial modeling; and in one scenario, more than half of Mexico was found to be at high risk of introduction, with an estimated 78 million people exposed. A positive association was identified between significant risk areas (p < 0.001). CONCLUSION: More than 50% of Mexican territory was found to be at risk of introduction of the causative agent of influenza type A, with approximately 70% of the population exposed.


OBJETIVO: Estimar o cenário probabilístico em potencial de introdução do vírus da influenza A no México com o uso de inteligência geográfica em saúde. MÉTODOS: Estudo ecológico de 1.973 surtos mundiais de influenza de alta patogenicidade ocorridos no período 2014­2016. Foi desenvolvido um modelo geoespacial com ferramentas de inteligência geográfica, como representação espacial, modelo de conexidade, caracterização espacial da fonte de inóculo com o modelo de máxima entropia e curva ROC (receiver operating characteristic) com avaliação espacial por múltiplos critérios e validação com o índice de Moran e regressão geograficamente ponderada. RESULTADOS: Foram estimadas isócronas do risco de saúde com uma distância de 548 km e o crescimento exponencial destes linhas; até a quarta isócrona, foram identificadas as costas leste e oeste dos Estados Unidos (EUA) e parte da América Central como possível superfície que favorece a introdução do vírus. Foi também estimada uma curva ROC de 0,923, sendo identificados dois períodos de risco de introdução do vírus (setembro­março e abril­agosto) com trajetórias de norte-sul e sul-norte, respectivamente, com elevada autocorrelação positiva para o modelo geoespacial. Foi estimado um cenário em que mais da metade do México apresenta alto risco de introdução do vírus da influenza, com 78 milhões de pessoas expostas. E foi observada uma associação positiva entre as áreas de risco significativo (P < 0,001). CONCLUSÃO: Observa-se que mais de 50% do território mexicano está sob risco de introdução do vírus da influenza A, com cerca de 70% da população exposta.

9.
Am J Drug Alcohol Abuse ; 44(3): 403-412, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28481655

RESUMO

BACKGROUND: High alcohol intake on weekends (binge drinking) is more frequent in young adults, who could undergo early liver damage. Alcohol-induced liver damage is characterized by polymorphonuclear cell (PMN) infiltration, which can be represented in the peripheral blood by altered trafficking and activation profiles. OBJECTIVE: To evaluate the PMN trafficking and activation immunophenotypic profiles in people with a binge drinking pattern. METHODS: People with binge drinking (n = 18, 8 females) or at low risk (n = 16, 13 females) based on their AUDIT and HEPCA scores were studied. Hematic biometry and liver enzyme tests were conducted. Peripheral blood leukocytes were stained for CCR5, CCR4, and CXCR4 (trafficking) and CD69 and CD127 (activation). PMNs and monocytes were analyzed by FACS. The data were analyzed using the T-test and Mann-Whitney's U-test for contrasts and principal component and Fuzzy C means analyses for clustering, with p < 0.05 considered significant. RESULTS: Compared to the low-risk group, the binge group showed higher CCR5 expression on PMNs, decreases in the CD69 percentage and positive PMNs per microliter, and decreased CXCR4 expression on monocytes. Six immunophenotypical clusters were identified, all of which were distributed following the CCR5 and CXCR4 main vectors. CONCLUSION: Young adult binge drinkers have differential PMN trafficking and activation immunophenotypes, which could be related to the initial onset of alcoholic liver disease and a systemic inflammatory state in response to their alcohol consumption pattern. These findings could lead to the future development of an early diagnostic tool.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas/sangue , Leucócitos Mononucleares/imunologia , Monócitos/imunologia , Adulto , Consumo Excessivo de Bebidas Alcoólicas/imunologia , Feminino , Humanos , Imunofenotipagem , Masculino , Adulto Jovem
10.
Microbiology (Reading) ; 163(7): 1105-1115, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28699871

RESUMO

Azotobacter vinelandii, belonging to the Pseudomonadaceae family, is a free-living bacterium that has been considered to be a good source for the production of bacterial polymers such as alginate. In A. vinelandii the synthesis of this polymer is regulated by the Gac/Rsm post-transcriptional regulatory system, in which the RsmA protein binds to the mRNA of the biosynthetic algD gene, inhibiting translation. In several Pseudomonas spp. the two-component system CbrA/CbrB has been described to control a variety of metabolic and behavioural traits needed for adaptation to changing environmental conditions. In this work, we show that the A. vinelandii CbrA/CbrB two-component system negatively affects alginate synthesis, a function that has not been described in Pseudomonas aeruginosa or any other Pseudomonas species. CbrA/CbrB was found to control the expression of some alginate biosynthetic genes, mainly algD translation. In agreement with this result, the CbrA/CbrB system was necessary for optimal rsmA expression levels. CbrA/CbrB was also required for maximum accumulation of the sigma factor RpoS. This last effect could explain the positive effect of CbrA/CbrB on rsmA expression, as we also showed that one of the promoters driving rsmA transcription was RpoS-dependent. However, although inactivation of rpoS increased alginate production by almost 100 %, a cbrA mutation increased the synthesis of this polymer by up to 500 %, implying the existence of additional CbrA/CbrB regulatory pathways for the control of alginate production. The control exerted by CbrA/CbrB on the expression of the RsmA protein indicates the central role of this system in regulating carbon metabolism in A. vinelandii.


Assuntos
Azotobacter vinelandii/metabolismo , Proteínas de Bactérias/metabolismo , Flavoproteínas/metabolismo , Regulação Bacteriana da Expressão Gênica , Fatores de Transcrição/metabolismo , Alginatos , Azotobacter vinelandii/genética , Proteínas de Bactérias/genética , Flavoproteínas/genética , Ácido Glucurônico/biossíntese , Ácidos Hexurônicos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Fatores de Transcrição/genética , Transcrição Gênica
11.
Curr Microbiol ; 72(6): 671-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26858204

RESUMO

Azotobacter vinelandii is a soil bacterium that forms desiccation-resistant cysts, and the exopolysaccharide alginate is essential for this process. A. vinelandii also produces alginate under vegetative growth conditions, and this production has biotechnological significance. Poly-ß-hydroxybutyrate (PHB) is another polymer synthetized by A. vinelandii that is of biotechnological interest. The GacS/A two-component signal transduction system plays an important role in regulating alginate production, PHB synthesis, and encystment. GacS/A in turn controls other important regulators such as RpoS and the ncRNAs that belong to the Rsm family. In A. vinelandii, RpoS is necessary for resisting oxidative stress as a result of its control over the expression of the catalase Kat1. In this work, we characterized a new ncRNA in A. vinelandii that is homologous to the P16/RsgA reported in Pseudomonas. We found that the expression of rgsA is regulated by GacA and RpoS and that it was essential for oxidative stress resistance. However, the activity of the catalase Kat1 is unaffected in rgsA mutants. Unlike those reported in Pseudomonas, RgsA in A. vinelandii regulates biofilm formation but not polymer synthesis or the encystment process.


Assuntos
Azotobacter vinelandii/fisiologia , Biofilmes , Estresse Oxidativo , RNA Bacteriano/metabolismo , RNA Longo não Codificante/metabolismo , Azotobacter vinelandii/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Regulação Bacteriana da Expressão Gênica , Dados de Sequência Molecular , Regiões Promotoras Genéticas , RNA Bacteriano/genética , RNA Longo não Codificante/genética , Fator sigma/genética , Fator sigma/metabolismo
12.
Arch Ital Biol ; 153(1): 46-55, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26441365

RESUMO

We  investigated whether healthy subjects with high (highs) and low (lows) hypnotizability scores differ in the ability to report the position of their right hand in the horizontal plane at the end of passive and active arm movements directed to lateral, intermediate and medial targets of the right hemispace under correct or incorrect visual feedback. Results showed that incorrect visual feedback increased the error in both groups. In lows, the error was similar after active and passive movements; in highs, it was lower for active than passive movements toward the medial position, but lower for passive than for active movements for the lateral one. The highs' error was significantly lower than the lows' one only for the active movements directed toward the medial hand position. Hypnotizability-related differences may be due to different role of efferent copies in highs and lows.


Assuntos
Mãos/fisiologia , Hipnose , Propriocepção/fisiologia , Vias Eferentes/fisiologia , Retroalimentação Sensorial , Feminino , Humanos , Movimento/fisiologia , Equilíbrio Postural , Desempenho Psicomotor/fisiologia , Adulto Jovem
13.
Microbiology (Reading) ; 160(Pt 3): 479-487, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24385478

RESUMO

In Azotobacter vinelandii, a cyst-forming bacterium, the alternative sigma factor RpoS is essential to the formation of cysts resistant to desiccation and to synthesis of the cyst-specific lipids, alkylresorcinols. In this study, we carried out a proteome analysis of vegetative cells and cysts of A. vinelandii strain AEIV and its rpoS mutant derivative AErpoS. This analysis allowed us to identify a small heat-shock protein, Hsp20, as one of the most abundant proteins of cysts regulated by RpoS. Inactivation of hsp20 did not affect the synthesis of alkylresorcinols or the formation of cysts with WT morphology; however, the cysts formed by the hsp20 mutant strain were unable to resist desiccation. We also demonstrated that expression of hsp20 from an RpoS-independent promoter in the AErpoS mutant strain is not enough to restore the phenotype of resistance to desiccation. These results indicate that Hsp20 is essential for the resistance to desiccation of A. vinelandii cysts, probably by preventing the aggregation of proteins caused by the lack of water. To our knowledge, this is the first report of a small heat-shock protein that is essential for desiccation resistance in bacteria.


Assuntos
Azotobacter vinelandii/genética , Azotobacter vinelandii/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Choque Térmico HSP20/genética , Proteínas de Choque Térmico HSP20/metabolismo , Fator sigma/genética , Fator sigma/metabolismo , Sequência de Bases , Dessecação , Inativação Gênica , Proteínas de Choque Térmico HSP20/química , Metabolismo dos Lipídeos , Dados de Sequência Molecular , Mutação , Regiões Promotoras Genéticas , Proteoma , Proteômica , Processamento Pós-Transcricional do RNA , Transcrição Gênica
14.
Rev Panam Salud Publica ; 36(5): 342-7, 2014 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-25604105

RESUMO

This paper discusses the gestation process, implementation methodology, and results obtained from the initiative to use e-learning to train human resources for health, six years after the launch of the Virtual Campus of Public Health of the University of Guadalajara (Mexico); the discussion is framed by Pan American Health Organization (PAHO) standards and practices. This is a special report on the work done by the institutional committee of the Virtual Campus in western Mexico to create an Internet portal that follows the guidelines of the strategic model established by Nodo México and PAHO for the Region of the Americas. This Virtual Campus began its activities in 2007, on the basis of the use of free software and institutional collaboration. Since the initial year of implementation of the node, over 500 health professionals have been trained using virtual courses, the node's educational platform, and a repository of virtual learning resources that are interoperable with other repositories in Mexico and the Region of the Americas. The University of Guadalajara Virtual Campus committee has followed the proposed model as much as possible, thereby achieving most of the goals set in the initial work plan, despite a number of administrative challenges and the difficulty of motivating committee members.


Assuntos
Educação a Distância/organização & administração , Saúde Pública/educação , Desenvolvimento de Pessoal/métodos , Pessoal de Saúde , Humanos , Internet , México , Organização Pan-Americana da Saúde
15.
Nutrients ; 16(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38337669

RESUMO

Body composition assessment using instruments such as dual X-ray densitometry (DXA) can be complex and their use is often limited to research. This cross-sectional study aimed to develop and validate a densitometric method for fat mass (FM) estimation using 3D cameras. Using two such cameras, stereographic images, and a mesh reconstruction algorithm, 3D models were obtained. The FM estimations were compared using DXA as a reference. In total, 28 adults, with a mean BMI of 24.5 (±3.7) kg/m2 and mean FM (by DXA) of 19.6 (±5.8) kg, were enrolled. The intraclass correlation coefficient (ICC) for body volume (BV) was 0.98-0.99 (95% CI, 0.97-0.99) for intra-observer and 0.98 (95% CI, 0.96-0.99) for inter-observer reliability. The coefficient of variation for kinetic BV was 0.20 and the mean difference (bias) for BV (liter) between Bod Pod and Kinect was 0.16 (95% CI, -1.2 to 1.6), while the limits of agreement (LoA) were 7.1 to -7.5 L. The mean bias for FM (kg) between DXA and Kinect was -0.29 (95% CI, -2.7 to 2.1), and the LoA was 12.1 to -12.7 kg. The adjusted R2 obtained using an FM regression model was 0.86. The measurements of this 3D camera-based system aligned with the reference measurements, showing the system's feasibility as a simpler, more economical screening tool than current systems.


Assuntos
Composição Corporal , Imageamento Tridimensional , Estudos Transversais , Reprodutibilidade dos Testes , Absorciometria de Fóton/métodos , Impedância Elétrica , Índice de Massa Corporal
16.
Artigo em Inglês | MEDLINE | ID: mdl-36731355

RESUMO

The gut microbiome produces a range of short chain fatty acids (SCFA) crucially linked with diet and nutrition, metabolism, gastrointestinal health and homeostasis. SCFA are primarily measured using gas or liquid chromatography-mass spectrometry (LC/MS) after undergoing chemical derivatization. Here we assess the merits of a derivatization protocol using aniline and two aniline analogues (3-phenoxyaniline and 4-(benzyloxy)aniline) for the targeted LC-MS/MS quantification of nine SCFA (acetic, propionic, butyric, valeric, caproic acid, isobutyric, isovaleric, 2-methylbutyric, and 2-ethylbutyric acid). Evaluation of product ion spectra and optimization of MS detection conditions, provided superior detection sensitivity for 3-phenoxyaniline and 4-(benzyloxy)aniline compared to aniline. We developed a facile SCFA derivatization method using 3-phenoxyaniline under mild reaction conditions which allows for the simultaneous quantification of these SCFA in human stool samples in under eleven minutes using multiple reaction monitoring LC-MS/MS. The method was successfully validated and demonstrates intra- and inter-day accuracy (88.5-103% and 86.0-109%) and precision (CV of 0.55-7.00% and 0.33-9.55%) with recoveries (80.1-87.2% for LLOQ, 88.5-93.0% for ULOQ) and carry-over of (2.68-17.9%). Selectivity, stability and matrix effects were also assessed and satisfied validation criteria. Method applicability was demonstrated by analysing SCFA profiles in DNA-stabilized human stool samples from newly diagnosed colorectal cancer patients prior to surgery. The development of this improved method and its compatibility to measure SCFAs from DNA-stabilized stool will facilitate studies investigating the gut microbiome in health and disease.


Assuntos
Ácidos Graxos Voláteis , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Ácidos Graxos Voláteis/análise , Fezes/química , Ácido Acético , Compostos de Anilina/análise , Ácidos Graxos/análise
17.
Int J Med Robot ; 19(6): e2572, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37671968

RESUMO

BACKGROUND: Lumbar puncture is an essential medical procedure whose objective is to obtain cerebrospinal fluid. Lumbar puncture is considered a complex procedure, mainly for novice residents who suffer from stress and low confidence, which may result in harm to the patient. METHODS: The LPVirSim, has been developed in four stages: i) requirements analysis through user-centred design; ii) prototyping of the virtual environment and the haptic component; iii) preliminary tests with Ph.D. students and physicians using two haptic devices (Omega.7 and Sigma.7); iv) a user study where physicians evaluated the usability and user experience. RESULTS: The LPVirSim integrates non-technical skills and the possibility of representing different patients for training. Usability increased from 61.76 to 68.75 in the preliminary tests to 71.43 in the user study. CONCLUSIONS: All the results showed good usability and demonstrated that the simulator arouses interest and realistically represents a Lumbar puncture, through the force and visual feedback.


Assuntos
Punção Espinal , Estudantes de Medicina , Humanos , Simulação por Computador , Interface Usuário-Computador , Competência Clínica
18.
Gels ; 9(12)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38131930

RESUMO

Synthetic phantoms that recreate the characteristics of biological tissues are valuable tools for systematically studying and comprehending physiologies, pathologies, and biological processes related to tissues. The reproduction of mechanical and optical properties allows for the development and evaluation of novel systems and applications in areas such as imaging, optics, ultrasound, or dosimetry, among others. This paper proposes a methodology for manufacturing agarose-based phantoms that mimics the optical properties of healthy brain tissue within the wavelength infrared range of 800 to 820 nm. The fabrication of such phantoms enables the possibility of testing and experimentation in controlled and safe environments toward the design of new near-infrared multispectral imaging systems in neurosurgery. The results of an experimental optical characterization study indicate the validity and reliability of the proposed method for fabricating brain tissue phantoms in a cost-effective and straightforward fashion.

19.
Asian Pac J Cancer Prev ; 24(8): 2621-2628, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37642047

RESUMO

OBJECTIVE: The aim of this study was to show how a geospatial model can be used to identify areas with a higher probability for late-stage breast cancer (BC) diagnoses. METHODS: Our study considered an ecological design. Clinical records at a tertiary care hospital were reviewed in order to obtain the place of residence and stage of the disease, which was classified as early (0-IIA) and late (IIB-IV) and whose diagnoses were made during the 2013-2017 period. Then, they were geolocated to identify the distribution and spatial trend. Subsequently, the pattern of location, i.e. scattered, random and concentrated, was statistically assessed and a geospatial model was elaborated to determine the probability of late diagnoses in the state of Jalisco, Mexico. RESULT: There were 1 954 (N) geolocated BC diagnoses: 58.3% were late. During the five-year period, a southwest-northeast trend was identified, nearly 9.5% of the surface of Jalisco, where 6 out of 10 (n= 751) late- stage diagnoses were concentrated. A concentrated and statistically significant pattern was identified in the southern, central and northern Pacific area of Jalisco, where the geospatial model delimited the places with the highest probability of late clinical stages (p <0.05). CONCLUSION: The geographical differences associated with the late diagnoses of BC suggest it is necessary to adapt and focus the strategies for early detection as an alternative to create a major impact on the population. Reproducible analysis tools were used in other contexts where geolocation data are available to complement public policies and strategies aimed to control BC.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , México/epidemiologia , Probabilidade , Política Pública
20.
Int J Med Robot ; 19(5): e2529, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37272193

RESUMO

BACKGROUND: Ventricular puncture is a common procedure in neurosurgery and the first that resident must learn. Ongoing education is critical to improving patient outcomes. However, training at the expense of potential risk to patients warrants new and safer training methods for residents. METHODS: An augmented reality (AR) simulator for the practice of ventricular punctures was designed. It consists of a navigation system with a virtual 3D projection of the anatomy over a 3D-printed patient model. Forty-eight participants from neurosurgery staff performed two free-hand ventricular punctures before and after a training session. RESULTS: Participants achieved enhanced accuracy in reaching the target at the Monro foramen after practicing with the system. Additional metrics revealed significantly better trajectories after the training. CONCLUSION: The study confirms the feasibility of AR as a training tool. This motivates future work towards standardising new educative methodologies in neurosurgery.


Assuntos
Realidade Aumentada , Neurocirurgia , Treinamento por Simulação , Humanos , Ventriculostomia/educação , Simulação por Computador , Procedimentos Neurocirúrgicos , Treinamento por Simulação/métodos
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