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Renal complications are long-term effect of diabetes mellitus where glucose is excreted in urine. Therefore, reliable glucose detection in urine is critical. While commercial urine strips offer a simple way to detect urine sugar, poor sensitivity and low reliability limit their use. A hybrid glucose oxidase (GOx)/horseradish peroxidase (HRP) assay remains the gold standard for pathological detection of glucose. A key restriction is poor stability of HRP and its suicidal inactivation by hydrogen peroxide, a key intermediate of the GOx-driven reaction. An alternative is to replace HRP with a robust inorganic enzyme-mimic or NanoZyme. While colloidal NanoZymes show promise in glucose sensing, they detect low concentrations of glucose, while urine has high (mM) glucose concentration. In this study, a free-standing copper NanoZyme is used for the colorimetric detection of glucose in human urine. The sensor could operate in a biologically relevant dynamic linear range of 0.5-15 mM, while showing minimal sample matrix effect such that glucose could be detected in urine without significant sample processing or dilution. This ability could be attributed to the Cu NanoZyme that for the first time showed an ability to promote the oxidation of a TMB substrate to its double oxidation diimine product rather than the charge-transfer complex product commonly observed. Additionally, the sensor could operate at a single pH without the need to use different pH conditions as used during the gold standard assay. These outcomes outline the high robustness of the NanoZyme sensing system for direct detection of glucose in human urine. Graphical abstract.
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Cobre/química , Glucosa/análisis , Glucosuria/orina , Nanopartículas del Metal/química , Materiales Biomiméticos/química , Catálisis , Coloides/química , Colorimetría/métodos , Humanos , Límite de Detección , Nanopartículas del Metal/ultraestructura , Oxidación-ReducciónRESUMEN
Insect-borne parasite Trypanosoma brucei plagues humans and other animals, eliciting the disease Human African trypanosomiasis, also known as African sleeping sickness. This disease poses the biggest threat to the people in Sub-Saharan Africa. Given the high toxicity and difficulties with administration of currently available drugs, a novel treatment is needed. Building on known Human African trypanosomiasis structure-activity relationship (SAR), we now describe a number of functionally simple diphenyl ether analogs which give low micromolar activity (IC50 = 0.16-0.96 µM) against T. b. rhodesiense. The best compound shows favorable selectivity against the L6 cell line (SI = 750) and even greater selectivity (SI = 1200) against four human cell lines. The data herein provides direction for the ongoing optimization of antitrypanosomal diphenyl ethers.
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Bencilaminas/química , Bencilaminas/farmacología , Tripanocidas/química , Tripanocidas/farmacología , Trypanosoma brucei rhodesiense/efectos de los fármacos , Tripanosomiasis Africana/tratamiento farmacológico , Línea Celular , Humanos , Éteres Fenílicos/química , Éteres Fenílicos/farmacología , Relación Estructura-Actividad , Tripanosomiasis Africana/parasitologíaRESUMEN
Approximately 20% of breast cancer cases are attributed to increased family risk, yet variation in BRCA1/2 can only explain 20%-25% of cases. Historically, only single gene or single variant testing were common in at-risk family members, and further sequencing studies were rarely offered after negative results. In this study, we applied an efficient and inexpensive targeted sequencing approach to provide molecular diagnoses in 245 human samples representing 134 BRCA mutation-negative (BRCAX) hereditary breast and ovarian cancer (HBOC) families recruited from 1973 to 2019 by Dr. Henry Lynch. Sequencing identified 391 variants, which were functionally annotated and ranked based on their predicted clinical impact. Known pathogenic CHEK2 breast cancer variants were identified in five BRCAX families in this study. While BRCAX was an inclusion criterion for this study, we still identified a pathogenic BRCA2 variant (p.Met192ValfsTer13) in one family. A portion of BRCAX families could be explained by other hereditary cancer syndromes that increase HBOC risk: Li-Fraumeni syndrome (gene: TP53) and Lynch syndrome (gene: MSH6). Interestingly, many families carried additional variants of undetermined significance (VOUSs) that may further modify phenotypes of syndromic family members. Ten families carried more than one potential VOUS, suggesting the presence of complex multi-variant families. Overall, nine BRCAX HBOC families in our study may be explained by known likely pathogenic/pathogenic variants, and six families carried potential VOUSs, which require further functional testing. To address this, we developed a functional assay where we successfully re-classified one family's PMS2 VOUS as benign.
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Proteína BRCA1 , Proteína BRCA2 , Neoplasias de la Mama , Predisposición Genética a la Enfermedad , Neoplasias Ováricas , Linaje , Humanos , Femenino , Proteína BRCA2/genética , Predisposición Genética a la Enfermedad/genética , Proteína BRCA1/genética , Neoplasias de la Mama/genética , Neoplasias Ováricas/genética , Síndrome de Cáncer de Mama y Ovario Hereditario/genética , Síndrome de Cáncer de Mama y Ovario Hereditario/diagnóstico , Adulto , Persona de Mediana Edad , Pruebas Genéticas/métodos , Fenotipo , Mutación , Quinasa de Punto de Control 2/genéticaRESUMEN
The microtubule (MT)-stabilizing drug Taxol (paclitaxel) is a commonly used tool to investigate MT dynamics and MT-dependent processes. Here, we present a protocol for using Taxol-sensitized budding yeast to investigate the effect of microtubule stabilization on anaphase onset. We describe steps for establishing a log phase culture, synchronizing cells in G1, arresting in metaphase, and releasing cells into Taxol. We then detail procedures for imaging and scoring anaphase onset. This protocol facilitates maintenance and reproducibility in testing drug-sensitized and Taxol-sensitized yeast strains. For complete details on the use and execution of this protocol, please refer to Proudfoot et al.1.
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Paclitaxel , Saccharomycetales , Paclitaxel/farmacología , Anafase , Reproducibilidad de los Resultados , Microtúbulos , Saccharomyces cerevisiaeRESUMEN
The ability to detect glucose concentrations in human urine offers a non-invasive approach to monitor changes in blood glucose, kidney health and vascular complications associated with diabetes. We show the potential of employing catalytically active nanoparticles directly grown on textiles to produce a dose-dependent colorimetric sensor for glucose. We use a galvanic replacement (GR) reaction for the synthesis of bimetallic nanoparticles. Here, Cu nanoparticles act as a sacrificial template that undergoes a spontaneous electroless GR reaction when exposed to metal ions of gold, silver, platinum, and palladium to form bimetallic Cu-M nanoparticles (M = Au, Ag, Pt, or Pd). The evaluation of their intrinsic peroxidase-mimicking catalytic activity ("nanozyme") in comparison to that of the Cu nanozyme revealed that the bimetallic systems show a higher catalytic rate with the Cu-Pt nanozyme showing the highest catalytic efficiency. This property of the Cu-Pt nanozyme was then utilized to detect glucose in human urine using the glucose oxidase enzyme as a molecular recognition element. A key outcome of our study is the ability to detect urine glucose without requiring sample dilution which is an advantage over the gold standard GOx-POx method and significantly more reliable performance over commercial urine glucose dipsticks. The difference in the intensity of the colorimetric response between different glucose concentrations further allowed this sensor system to be combined with digital imaging tools for multivariate analysis.
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Técnicas Biosensibles , Glucosuria , Nanopartículas del Metal , Técnicas Biosensibles/métodos , Glucemia/análisis , Automonitorización de la Glucosa Sanguínea , Colorimetría/métodos , Análisis Discriminante , Glucosa/análisis , HumanosRESUMEN
The development of hydrogels resulting from the self-assembly of low molecular weight (LMW) hydrogelators is a rapidly expanding area of study. Fluorenylmethoxycarbonyl (Fmoc) protected aromatic amino acids derived from phenylalanine (Phe) have been shown to be highly effective LMW hydrogelators. It has been found that side chain functionalization of Fmoc-Phe exerts a significant effect on the self-assembly and hydrogelation behavior of these molecules; fluorinated derivatives, including pentafluorophenylalanine (F(5)-Phe) and 3-F-phenylalanine (3-F-Phe), spontaneously self-assemble into fibrils that form a hydrogel network upon dissolution into water. In this study, Fmoc-F(5)-Phe-OH and Fmoc-3-F-Phe-OH were used to characterize the role of the C-terminal carboxylic acid on the self-assembly and hydrogelation of these derivatives. The C-terminal carboxylic acid moieties of Fmoc-F(5)-Phe-OH and Fmoc-3-F-Phe-OH were converted to C-terminal amide and methyl ester groups in order to perturb the hydrophobicity and hydrogen bond capacity of the C-terminus. Self-assembly and hydrogelation of these derivatives was investigated in comparison to the parent carboxylic acid compounds at neutral and acidic pH. It was found that hydrogelation of the C-terminal acids was highly sensitive to solvent pH, which influences the charge state of the terminal group. Rigid hydrogels form at pH 3.5, but at pH 7 hydrogel rigidity is dramatically weakened. C-terminal esters self-assembled into fibrils only slowly and failed to form hydrogels due to the higher hydrophobicity of these derivatives. C-terminal amide derivatives assembled much more rapidly than the parent carboxylic acids at both acidic and neutral pH, but the resultant hydrogels were unstable to shear stress as a function of the lower water solubility of the amide functionality. Co-assembly of acid and amide functionalized monomers was also explored in order to characterize the properties of hybrid hydrogels; these gels were rigid in unbuffered water but significantly weaker in phosphate buffered saline. These results highlight the complex nature of monomer/solvent interactions and their ultimate influence on self-assembly and hydrogelation, and provide insight that will facilitate the development of optimal amino acid LMW hydrogelators for gelation of complex buffered media.
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Aminoácidos/química , Fluorenos/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Fenilalanina/química , Dicroismo Circular , Halogenación , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Transmisión , ReologíaRESUMEN
Controlling the kinetics of CuTCNQ (TCNQ = 7,7,8,8-tetracyanoquinodimethane) crystallization has been a major challenge, as CuTCNQ crystallizing on Cu foil during synthesis in conventional solvents such as acetonitrile simultaneously dissolves into the reaction medium. In this work, we address this challenge by using water as a universal co-solvent to control the kinetics of crystallization and growth of phase I CuTCNQ. Water increases the dielectric constant of the reaction medium, shifting the equilibrium toward CuTCNQ crystallization while concomitantly decreasing the dissolution of CuTCNQ. This allows more CuTCNQ to be controllably crystallized on the surface of the Cu foil. Different sizes of CuTCNQ crystals formed on Cu foil under different water/DMSO admixtures influence the solvophilicity of these materials. This has important implications in their catalytic performance, as water-induced changes in the surface properties of these materials can make them highly hydrophilic, which allows the CuTCNQ to act as an efficient catalyst as it brings the aqueous reactants in close vicinity of the catalyst. Evidently, the CuTCNQ synthesized in 30% (v/v) water/DMSO showed superior catalytic activity for ferricyanide reduction with 95% completion achieved within a few minutes in contrast to CuTCNQ synthesized in DMSO that took over 92 min.
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There is an error that needs to be corrected in the Funding and Acknowledgments statements of [...].
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The spindle assembly checkpoint (SAC) delays anaphase onset until sister chromosomes are bound to microtubules from opposite spindle poles. Only then can dynamic microtubules produce tension across sister kinetochores. The interdependence of kinetochore attachment and tension has proved challenging to understanding SAC mechanisms. Whether the SAC responds simply to kinetochore attachment or to tension status remains obscure. Unlike higher eukaryotes, budding yeast kinetochores bind only one microtubule, simplifying the relation between attachment and tension. We developed a Taxol-sensitive yeast model to reduce tension in fully assembled spindles. Our results show that low tension on bipolar-attached kinetochores delays anaphase onset, independent of detachment. The delay is transient relative to that imposed by unattached kinetochores. Furthermore, it is mediated by Bub1 and Bub3, but not Mad1, Mad2, and Mad3 (BubR1). Our results demonstrate that reduced tension delays anaphase onset via a signal that is temporally and mechanistically distinct from that produced by unattached kinetochores.
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Anafase/genética , Proteínas de Ciclo Celular/genética , Cinetocoros/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa/genética , Proteínas Serina-Treonina Quinasas/genética , HumanosRESUMEN
Enzyme-mimicking catalytic nanoparticles, more commonly known as NanoZymes, have been at the forefront for the development of new sensing platforms for the detection of a range of molecules. Although solution-based NanoZymes have shown promise in glucose detection, the ability to immobilize NanoZymes on highly absorbent surfaces, particularly on free-standing substrates that can be feasibly exposed and removed from the reaction medium, can offer significant benefits for a range of biosensing and catalysis applications. This work, for the first time, shows the ability of Ag nanoparticles embedded within the 3D matrix of a cotton fabric to act as a free-standing peroxidase-mimic NanoZyme for the rapid detection of glucose in complex biological fluids such as urine. The use of cotton fabric as a template not only allows high number of catalytically active sites to participate in the enzyme-mimic catalytic reaction, the absorbent property of the cotton fibres also helps in rapid absorption of biological molecules such as glucose during the sensing event. This, in turn, brings the target molecule of interest in close proximity of the NanoZyme catalyst enabling accurate detection of glucose in urine. Additionally, the ability to extract the free-standing cotton fabric-supported NanoZyme following the reaction overcomes the issue of potential interference from colloidal nanoparticles during the assay. Based on these unique characteristics, nanostructured silver fabrics offer remarkable promise for the detection of glucose and other biomolecules in complex biological and environmental fluids.
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Materiales Biomiméticos/química , Técnicas Biosensibles/métodos , Diabetes Mellitus/orina , Glucosa/análisis , Glucosuria/orina , Nanoestructuras/química , Plata/química , Catálisis , Colorimetría/métodos , Fibra de Algodón , Humanos , Nanoestructuras/ultraestructura , Peroxidasas/químicaRESUMEN
To function in diverse cellular processes, the dynamic properties of microtubules must be tightly regulated. Cellular microtubules are influenced by a multitude of regulatory proteins, but how their activities are spatiotemporally coordinated within the cell, or on specific microtubules, remains mostly obscure. The conserved kinesin-8 motor proteins are important microtubule regulators, and family members from diverse species combine directed motility with the ability to modify microtubule dynamics. Yet how kinesin-8 activities are appropriately deployed in the cellular context is largely unknown. Here we reveal the importance of the nonmotor tail in differentially controlling the physiological functions of the budding yeast kinesin-8, Kip3. We demonstrate that the tailless Kip3 motor domain adequately governs microtubule dynamics at the bud tip to allow spindle positioning in early mitosis. Notably, discrete regions of the tail mediate specific functions of Kip3 on astral and spindle microtubules. The region proximal to the motor domain operates to spatially regulate astral microtubule stability, while the distal tail serves a previously unrecognized role to control the timing of mitotic spindle disassembly. These findings provide insights into how nonmotor tail domains differentially control kinesin functions in cells and the mechanisms that spatiotemporally control the stability of cellular microtubules.
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Cinesinas/química , Cinesinas/metabolismo , Microtúbulos/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Huso Acromático/metabolismo , Alelos , Anafase , Mutación con Ganancia de Función , Relación Estructura-Actividad , Factores de TiempoRESUMEN
Objective: the study aimed to expose the practice of an activity of extension performed in order to train agents of the Federal Penitentiary of Mossoró/RN. Methods: For implementation of Basic Life Support (BLS) in urgency/emergency situations. The activity took place from November 2012 to September 2013, coordinated by a professor, with the participation of 09 students of the Faculty of Nursing at the University of Rio Grande do Norte. Results: This work allowed the correctional officers to improve previous notions about the theme, as well as acquire new knowledge in view of the possibility to apply them in their daily professional life and also personal. Conclusion: In this sense, the project objectives were included in the progress was evidence during the stages of teaching and learning.
Objetivo: expor a prática de uma atividade de extensão realizada no intuito de capacitar os agentes penitenciários da Penitenciária Federal de Mossoró/RN. Métodos: Para aplicação do Suporte Básico de Vida (SBV) em situações de urgência/emergência. A atividade aconteceu no período de novembro de 2012 a setembro de 2013, coordenado por um docente, com a participação de 09 discentes da Faculdade de Enfermagem da Universidade do Estado do Rio Grande do Norte. Resultados: A realização deste trabalho permitiu aos agentes penitenciários aperfeiçoar noções prévias acerca da temática, bem como adquirir novos conhecimentos, tendo em vista a possibilidade de aplicá-los no seu cotidiano no âmbito profissional, como também pessoal. Conclusão: Nesse sentido, os objetivos do projeto foram contemplados na medida em que foram evidenciados os avanços durante as etapas do ensino-aprendizagem.
Objetivo: el estudio tuvo como objetivo exponer la práctica de una extensión de la actividad que se realiza con el fin de capacitar a los oficiales correccionales de la Penitenciaría Federal de Mossoró/ RN. Métodos: Para la implementación de Soporte Vital Básico (SVB) en situaciones de urgencia/emergencia. La actividad se llevó a cabo a partir de noviembre 2012 a septiembre 2013, coordinado por un profesor, con la participación de 09 estudiantes de la Facultad de Enfermería de la Universidad de Río Grande do Norte. Resultados: Este trabajo permitió a los oficiales correccionales mejorar nociones previas sobre el tema, así como adquirir nuevos conocimientos, teniendo encuenta la posibilidad de aplicar los en su vida diaria en el profesional, sino también personal. Conclusión: En este sentido, se incluyeron los objetivos del proyecto en que el progreso era evidente durante las etapas de la enseñanza y el aprendizaje.
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Masculino , Femenino , Humanos , Reanimación Cardiopulmonar/educación , Capacitación de Recursos Humanos en Salud , Prisiones , Capacitación Profesional , Desarrollo de Personal , Cursos de Capacitación , BrasilRESUMEN
Objetivo: analisar a compreensão da equipe multiprofissional sobre a prática de educação em saúde no cotidiano do seu trabalho e sua importância na prevenção e controle da hipertensão arterial. Método: estudo descritivo com abordagem qualitativa realizado com 11 profissionais da equipe três da Estratégia de Saúde da Família (ESF), da zona rural do município de Antônio Martins, RN/Brasil, a partir de uma entrevista semiestruturada. O projeto foi aprovado pelo Comitê de Ética e Pesquisa (CEP), CAEE 0066.0.428.000-09. Resultados: constatou-se que as práticas de educação em saúde desenvolvidas pela equipe são muito insipientes e que as metodologias empregadas são realizadas de forma prescritiva e hierarquizadas. Conclusão: é necessário que haja reestruturação dos serviços de saúde e capacitação de toda a equipe da ESF, assim como maior disponibilidade de recursos físicos e materiais de apoio adequado.(AU)
Objective: to analyze the understanding of the multidisciplinary team of health education practices in everyday work and its importance in the prevention and control of hypertension. Method: a descriptive qualitative study carried out with eleven professional team three of the Family Health Strategy (ESF), in the rural area Antonio Martins, RN/Brazil, from a semi-structured interview. The project was approved by the Research Ethics Committee (CEP), CAEE 0066.0.428.000-09. Results: it was found that the health education practices developed by the team are very ignorant and the methodologies used are made of prescriptive and hierarchical way. Conclusion: there are needs to restructure health services and training for the entire staff of the ESF, as well as greater availability of physical resources and appropriate material support.(AU)
Objetivo: analizar la comprensión del equipo multiprofesional sobre la práctica de educación en salud en el cotidiano de su trabajo y su importancia en la prevención y control de la hipertensión arterial. Método: estudio descriptivo con enfoque cualitativo realizado con once profesionales del equipo tres de la Estrategia de Salud de la Familia (ESF), de la zona rural de la ciudad de Antônio Martins, RN/Brasil, a partir de una entrevista semi-estructurada. El proyecto fue aprobado por el Comité de Ética e Investigación (CEP), CAEE 0066.0.428.000-09. Resultados: se constató que las prácticas de educación en salud desarrolladas por el equipo son muy insipientes y las metodologías empleadas son realizadas de forma prescriptiva y jerárquica. Conclusión: es necesario que haya reestructuración de los servicios de salud y capacitación de todo el equipo de la ESF, así como, mayor disponibilidad de recursos físicos y materiales de apoyo adecuado.(AU)
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Humanos , Masculino , Femenino , Grupo de Atención al Paciente , Pacientes , Estrategias de Salud Nacionales , Educación en Salud , Hipertensión , Hipertensión/prevención & control , Epidemiología Descriptiva , Investigación CualitativaRESUMEN
The study attempted to distinguish avoidant vs. secure infants at 1 year from 4-month infant behavior only, during a face-to-face play interaction with the mother. Thirty-five 4-month-old infants were coded second by second for infant gaze, head orientation, facial expression and self-touch/mouthing behavior. Mother behavior was not coded. At 1 year, 27 of these infants were classified as secure (B), and 8 as avoidant (A) attachment in the Ainsworth Strange Situation. Compared with the B infant, the future A infant spent less time paying 'focused' visual attention (a look of a minimum 2 seconds duration) to the mother's face. Only if the A infant engaged in self-touch/mouthing behavior did its focused visual attention match that of the B. Markovian t to t+1 transition matrices then showed that both for future A and for future B infants, focused visual attention on the mother constrained the movements of the head to within 60 degrees from center vis-à-vis, defining head/gaze co-ordination within an attentional-interpersonal space. However, infant maintenance of head/gaze co-ordination was associated with self-touch/mouthing behavior for the A infant but not the B. Positive affect was associated with a disruption of head/gaze co-ordination for the A but not the B. Whereas the B had more variable facial behavior, potentially providing more facial signaling for the mother, the A had more variable tactile/mouthing behavior, changing patterns of self-soothing more often. Thus, infants classified as A vs. B at 12 months showed different behavioral patterns in face-to-face play with their mothers as early as 4 months.