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1.
Nucleic Acids Res ; 51(21): 11453-11465, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37823611

RESUMO

SINE-VNTR-Alu (SVA) retrotransposons are evolutionarily young and still-active transposable elements (TEs) in the human genome. Several pathogenic SVA insertions have been identified that directly mutate host genes to cause neurodegenerative and other types of diseases. However, due to their sequence heterogeneity and complex structures as well as limitations in sequencing techniques and analysis, SVA insertions have been less well studied compared to other mobile element insertions. Here, we identified polymorphic SVA insertions from 3646 whole-genome sequencing (WGS) samples of >150 diverse populations and constructed a polymorphic SVA insertion reference catalog. Using 20 long-read samples, we also assembled reference and polymorphic SVA sequences and characterized the internal hexamer/variable-number-tandem-repeat (VNTR) expansions as well as differing SVA activity for SVA subfamilies and human populations. In addition, we developed a module to annotate both reference and polymorphic SVA copies. By characterizing the landscape of both reference and polymorphic SVA retrotransposons, our study enables more accurate genotyping of these elements and facilitate the discovery of pathogenic SVA insertions.


Assuntos
Genoma Humano , Retroelementos , Humanos , Elementos Alu , Genoma Humano/genética , Repetições Minissatélites/genética , Retroelementos/genética , Elementos Nucleotídeos Curtos e Dispersos
2.
Int J Mol Sci ; 25(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38612729

RESUMO

The delineation of biomarkers and neuropsychiatric symptoms across normal cognition, mild cognitive impairment (MCI), and dementia stages holds significant promise for early diagnosis and intervention strategies. This research investigates the association of neuropsychiatric symptoms, evaluated via the Neuropsychiatric Inventory (NPI), with cerebrospinal fluid (CSF) biomarkers (Amyloid-ß42, P-tau, T-tau) across a spectrum of cognitive states to enhance diagnostic accuracy and treatment approaches. Drawing from the National Alzheimer's Coordinating Center's Uniform Data Set Version 3, comprising 977 individuals with normal cognition, 270 with MCI, and 649 with dementia. To assess neuropsychiatric symptoms, we employed the NPI to understand the behavioral and psychological symptoms associated with each cognitive category. For the analysis of CSF biomarkers, we measured levels of Amyloid-ß42, P-tau, and T-tau using the enzyme-linked immunosorbent assay (ELISA) and Luminex multiplex xMAP assay protocols. These biomarkers are critical in understanding the pathophysiological underpinnings of Alzheimer's disease and its progression, with specific patterns indicative of disease stage and severity. This study cohort consists of 1896 participants, which is composed of 977 individuals with normal cognition, 270 with MCI, and 649 with dementia. Dementia is characterized by significantly higher NPI scores, which are largely reflective of mood-related symptoms (p < 0.001). In terms of biomarkers, normal cognition shows median Amyloid-ß at 656.0 pg/mL, MCI at 300.6 pg/mL, and dementia at 298.8 pg/mL (p < 0.001). Median P-tau levels are 36.00 pg/mL in normal cognition, 49.12 pg/mL in MCI, and 58.29 pg/mL in dementia (p < 0.001). Median T-tau levels are 241.0 pg/mL in normal cognition, 140.6 pg/mL in MCI, and 298.3 pg/mL in dementia (p < 0.001). Furthermore, the T-tau/Aß-42 ratio increases progressively from 0.058 in the normal cognition group to 0.144 in the MCI group, and to 0.209 in the dementia group (p < 0.001). Similarly, the P-tau/Aß-42 ratio also escalates from 0.305 in individuals with normal cognition to 0.560 in MCI, and to 0.941 in dementia (p < 0.001). The notable disparities in NPI and CSF biomarkers among normal, MCI and Alzheimer's patients underscore their diagnostic potential. Their combined assessment could greatly improve early detection and precise diagnosis of MCI and dementia, facilitating more effective and timely treatment strategies.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/diagnóstico , Afeto , Proteínas Amiloidogênicas , Biomarcadores , Cognição
3.
Methods ; 203: 542-557, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34197925

RESUMO

Fundamental to the functional behavior of cardiac muscle is that the cardiomyocytes are integrated as a functional syncytium. Disrupted electrical activity in the cardiac tissue can lead to serious complications including cardiac arrhythmias. Therefore, it is important to study electrophysiological properties of the cardiac tissue. With advancements in stem cell research, protocols for the production of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have been established, providing great potential in modelling cardiac arrhythmias and drug testing. The hiPSC-CM model can be used in conjunction with electrophysiology-based platforms to examine the electrical activity of the cardiac tissue. Techniques for determining the myocardial electrical activity include multielectrode arrays (MEAs), optical mapping (OM), and patch clamping. These techniques provide critical approaches to investigate cardiac electrical abnormalities that underlie arrhythmias.


Assuntos
Células-Tronco Pluripotentes Induzidas , Potenciais de Ação/fisiologia , Arritmias Cardíacas/genética , Células Cultivadas , Fenômenos Eletrofisiológicos , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Miócitos Cardíacos/fisiologia
4.
Angew Chem Int Ed Engl ; 62(6): e202215200, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36470851

RESUMO

Developing chemical tools to detect and influence biological processes is a cornerstone of chemical biology. Here we combine two tools which rely on orthogonality- perfluorocarbons and multiplexed shortwave infrared (SWIR) fluorescence imaging- to visualize nanoemulsions in real time in living mice. Drawing inspiration from fluorous and SWIR fluorophore development, we prepared two SWIR-emissive, fluorous-soluble chromenylium polymethine dyes. These are the most red-shifted fluorous fluorophores- "fluorofluorophores"-to date. After characterizing the dyes, their utility was demonstrated by tracking perfluorocarbon nanoemulsion biodistribution in vivo. Using an excitation-multiplexed approach to image two variables simultaneously, we gained insight into the importance of size and surfactant identity on biodistribution.


Assuntos
Fluorocarbonos , Imagem Óptica , Animais , Camundongos , Distribuição Tecidual , Imagem Óptica/métodos , Corantes Fluorescentes/química , Raios Infravermelhos
5.
Langmuir ; 38(5): 1845-1852, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35080398

RESUMO

Highly wetting and nonwetting substrates have been widely used in fogwater collection systems for enhanced water harvesting. In this work, fog harvesting substrates comprising PVC strips of different wetting properties and widths ranging from 1-5 mm were vertically aligned and spaced apart at regular intervals to give the same solid area fraction of 0.8. Evaluation of the water collection efficiencies of the tested configurations revealed that 1 mm wide superhydrophilic strips was the most efficient, achieving double the amount of water harvested compared with 2.8 mm wide strips. This finding was attributed to the low Stokes numbers of the aerosol particle distribution of the fog which tended to result in them being brought by the flow streamlines toward the air gaps between the strips. Stagnant flow regions at the edges of each strip, revealed through potential flow calculations, then caused higher liquid imbibition and impaction there for water harvesting. It was also found that the Cassie nonwetting substrates that originally exhibited contact angles of 161° transformed to Wenzel wetting with zero contact angle within 60 min of fog interception. Optical profilometry revealed no obvious difference in surface roughness between the central region and edges of the strips, indicating that surface morphology was unlikely to be a contributing factor for enhanced water collection at the edges. The findings here indicated that highly wetting vertical strip architectures with narrow widths (1 mm) were favorable over wider strips for water harvesting provided that clogging and re-entrainment were not significant factors.

6.
J Fluoresc ; 32(2): 443-448, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35064858

RESUMO

Low-cost analytical solutions built around microcomputers like the Raspberry Pi help to facilitate laboratory investigations in resource limited venues. Here, three camera modules (V1.3 with and without filter, as well as NoIR) that work with this microcomputer were assessed for their suitability in imaging fluorescent DNA following agarose gel electrophoresis. Evaluation of their utility was based on signal-to-noise (SNR) and noise variance metrics that were developed. Experiments conducted with samples were subjected to Polymerase Chain Reaction (PCR), and the amplified products were separated using gel electrophoresis and stained with Midori green. Image analysis revealed the NoIR camera performed the best with SNR and noise variance values of 21.7 and 0.222 respectively. In experiments conducted using UV LED lighting to simulate ethidium bromide (EtBr) excitation, the NoIR and V1.3 with filter removed cameras showed comparable SNR values.


Assuntos
DNA/análise , Eletroforese em Gel de Ágar/métodos , Corantes Fluorescentes , Microcomputadores , Reação em Cadeia da Polimerase , Coloração e Rotulagem
7.
Cryobiology ; 104: 98-101, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34838822

RESUMO

Cryopreservation is a widely used long-term preservation method to ensure the quality and vitality of microbes in laboratories and biological resource facilities. However, freeze-thaw damage and osmotic pressure changes during cryopreservation adversely impacts microbial survival. Significant expenditure of resources and expertise are required to select the right cryoprotectant and optimize its concentration for maximum survival of diverse microorganisms. This work describes a cryopreservation method that obviates the need for cryoprotectants by exploiting the unique thermal characteristics of semi-spherical drops. Here, a plurality of these drops, each 10 µl in volume, created on a highly non-wetting flat-sheet substrate with holes and frozen at -70 °C. Deriving an f (x) metric as a measure of relative viability, storage in drops in the absence of cryoprotectants was found to improve the survivability of Staphylococcus epidermidis by 1.91 times compared with the same sample stored in larger 50-µl volumes in standard 1.5-ml tubes. This also compares well with a value of 2.33 obtained with standard preservation with cryoprotectant. The drop method allows high throughput aliquoting of the bacterial culture into multiple discrete drops using multichannel pipettes or automated liquid handlers and the edges of the holes provides a pinning action that holds the drop stably against gravitational roll-offs. It also allows samples to be removed in discrete small volumes, thus, reducing the number of freeze thaw cycles and associated cell damage. The flat-sheet architecture of the substrate reduces the amount of plastic waste generated and augments green laboratory practices.


Assuntos
Criopreservação , Preservação do Sêmen , Bactérias , Criopreservação/métodos , Crioprotetores/farmacologia , Congelamento , Pressão Osmótica
8.
Proc Natl Acad Sci U S A ; 116(14): 6969-6974, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30886088

RESUMO

Sudden unexpected death of an infant (SUDI) is a devastating occurrence for families. To investigate the genetic pathogenesis of SUDI, we sequenced >70 genes from 191 autopsy-negative SUDI victims. Ten infants sharing a previously unknown variant in troponin I (TnI) were identified. The mutation (TNNI1 R37C+/-) is in the fetal/neonatal paralog of TnI, a gene thought to be expressed in the heart up to the first 24 months of life. Using phylogenetic analysis and molecular dynamics simulations, it was determined that arginine at residue 37 in TNNI1 may play a critical functional role, suggesting that the variant may be pathogenic. We investigated the biophysical properties of the TNNI1 R37C mutation in human reconstituted thin filaments (RTFs) using fluorometry. RTFs reconstituted with the mutant R37C TnI exhibited reduced Ca2+-binding sensitivity due to an increased Ca2+ off-rate constant. Furthermore, we generated TNNI1 R37C+/- mutants in human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) using CRISPR-Cas9. In monolayers of hiPSC-CMs, we simultaneously monitored voltage and Ca2+ transients through optical mapping and compared them to their isogenic controls. We observed normal intrinsic beating patterns under control conditions in TNNI1 R37C+/- at stimulation frequencies of 55 beats/min (bpm), but these cells showed no restitution with increased stimulation frequency to 65 bpm and exhibited alternans at >75 bpm. The WT hiPSC-CMs did not exhibit any sign of arrhythmogenicity even at stimulation frequencies of 120 bpm. The approach used in this study provides critical physiological and mechanistic bases to investigate sarcomeric mutations in the pathogenesis of SUDI.


Assuntos
Células-Tronco Pluripotentes Induzidas/metabolismo , Simulação de Dinâmica Molecular , Mutação de Sentido Incorreto , Miócitos Cardíacos/metabolismo , Morte Súbita do Lactente/genética , Troponina I , Cálcio/química , Cálcio/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Recém-Nascido , Contração Miocárdica/genética , Miócitos Cardíacos/patologia , Sarcômeros/genética , Sarcômeros/metabolismo , Sarcômeros/patologia , Morte Súbita do Lactente/patologia , Troponina I/química , Troponina I/genética , Troponina I/metabolismo
9.
Prof Psychol Res Pr ; 53(5): 494-503, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36212803

RESUMO

Background: Family caregivers of dementia patients experience high levels of interpersonal stress that often results in elevated anxiety, and depression, and negative impacts on interpersonal relationships. Changes in behaviors and the structure of relationships with the care recipient (CR) and others in the social milieu challenge the caregivers' ability to mentalize, or understand the links between mental states and behaviors. This study investigates the experiences and perceived benefits of family dementia caregivers who underwent Mentalizing Imagery Therapy (MIT), a treatment aiming to improve balanced self-other mentalizing and reduce psychological symptoms. Methods: Purposeful sampling was used to select 11 family dementia caregivers who underwent a 4-week pilot trial of MIT. Semi-structured interviews were completed post-intervention to identify subjective benefits, putative psychological mediators and perceived active components. Results: Caregivers reported improvements in well-being, mood, anxiety, and sleep, and a majority stated MIT helped with forming and maintaining healthier relationships. Some participants noted benefits extending to how they reacted to their social environment and perceived themselves more objectively from others' perspectives. Specific elements of MIT, including self-compassion, self-care, and the ability to reflect on emotionally arousing challenges, might have mediated these improvements. Conclusion: Family dementia caregivers perceived salutary benefits of MIT on multiple domains of well-being. The self reports suggest MIT holds promise for improving well-being, reducing non-mentalizing patterns of thought, and facilitating improvements in balanced mentalization within the caregivers' relationships.

10.
J Infect Dis ; 223(7): 1232-1240, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32779717

RESUMO

BACKGROUND: Globally, decreased susceptibility to ceftriaxone in Neisseria gonorrhoeae is rising. We aimed to compile a global collection of N. gonorrhoeae strains and assess the genetic characteristics associated with decreased susceptibility to ceftriaxone. METHODS: We performed a literature review of all published reports of N. gonorrhoeae strains with decreased susceptibility to ceftriaxone (>0.064 mg/L minimum inhibitory concentration) through October 2019. Genetic mutations in N. gonorrhoeae genes (penA, penB, mtrR, and ponA), including determination of penA mosaicism, were compiled and evaluated for predicting decreased susceptibility to ceftriaxone. RESULTS: There were 3821 N. gonorrhoeae strains identified from 23 countries and 684 (18%) had decreased susceptibility to ceftriaxone. High sensitivities or specificities (>95%) were found for specific genetic mutations in penA, penB, mtrR, and ponA, both with and without determination of penA mosaicism. Four algorithms to predict ceftriaxone susceptibility were proposed based on penA mosaicism determination and penA or non-penA genetic mutations, with sensitivity and specificity combinations up to 95% and 62%, respectively. CONCLUSION: Molecular algorithms based on genetic mutations were proposed to predict decreased susceptibility to ceftriaxone in N. gonorrhoeae. Those algorithms can serve as a foundation for the development of future assays predicting ceftriaxone decreased susceptibility within N. gonorrhoeae globally.


Assuntos
Antibacterianos , Ceftriaxona , Neisseria gonorrhoeae , Algoritmos , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Ceftriaxona/farmacologia , Testes de Sensibilidade Microbiana , Mutação , Neisseria gonorrhoeae/efeitos dos fármacos , Neisseria gonorrhoeae/genética
11.
J Antimicrob Chemother ; 76(11): 2847-2849, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34324655

RESUMO

BACKGROUND: Antimicrobial resistance (AMR) in Neisseria gonorrhoeae is an urgent global health threat. Zoliflodacin is a novel antibiotic undergoing clinical trials for the treatment of gonorrhoea. While there are limited data regarding zoliflodacin resistance in N. gonorrhoeae, three amino acid mutations have been associated with increased MICs of zoliflodacin. OBJECTIVES: To determine the prevalence of three amino acid mutations associated with zoliflodacin resistance within a large, public database of nearly 13 000 N. gonorrhoeae genomes. METHODS: PathogenWatch is an online genomic epidemiology platform with a public database of N. gonorrhoeae genomes. That database was used to extract gyrB sequence data and a Basic Local Alignment Search Tool (BLAST) search was performed to identify any of the three amino acid mutations in GyrB that are associated with increased zoliflodacin MICs: D429N, K450N or K450T. As a control for the search methodology, all GyrA sequences were also extracted and S91F mutations were identified and compared with the PathogenWatch database. RESULTS: In total, 12 493 N. gonorrhoeae genomes from the PathogenWatch database were included. Among those genomes, none was identified that harboured any of the three mutations associated with increased zoliflodacin MICs. One genome was identified to have a mutation at position 429 in GyrB (D429V). CONCLUSIONS: The findings suggest that the prevalence of the three mutations associated with zoliflodacin resistance in N. gonorrhoeae is very low. However, further research into the mechanisms of zoliflodacin resistance in N. gonorrhoeae is needed. Genomic epidemiology platforms like PathogenWatch can be used to enhance the global surveillance of AMR.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Barbitúricos , Farmacorresistência Bacteriana , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Humanos , Isoxazóis , Testes de Sensibilidade Microbiana , Morfolinas , Mutação , Neisseria gonorrhoeae/genética , Oxazolidinonas , Compostos de Espiro
12.
Anal Biochem ; 616: 114098, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33388295

RESUMO

A system devised to conduct Polymerase Chain Reaction (PCR) in-flight on drones that uses the spatial displacement of capillary tubes on thermal blocks kept at 94 °C, 58 °C and 72 °C corresponding to cycling temperatures for denaturation, annealing and extension is demonstrated here. The use of acetal as the thermal block material reduced heat loss and the input power (within 18.5 W) needed to maintain the required temperatures. Tests showed that concentrations of samples down to 1.16 × 106 DNA copies/µL could be significantly and consistently detected above the background emission of the fluorescence signal intensity.


Assuntos
Viagem Aérea , Aeronaves/instrumentação , Reação em Cadeia da Polimerase/métodos , Manejo de Espécimes/métodos , DNA/análise , Humanos , Temperatura , Fatores de Tempo
13.
FASEB J ; 34(7): 9051-9073, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32413188

RESUMO

Laminopathies are rare diseases associated with mutations in LMNA, which encodes nuclear lamin A/C. LMNA variants lead to diverse tissue-specific phenotypes including cardiomyopathy, lipodystrophy, myopathy, neuropathy, progeria, bone/skin disorders, and overlap syndromes. The mechanisms underlying these heterogeneous phenotypes remain poorly understood, although post-translational modifications, including phosphorylation, are postulated as regulators of lamin function. We catalogued all known lamin A/C human mutations and their associated phenotypes, and systematically examined the putative role of phosphorylation in laminopathies. In silico prediction of specific LMNA mutant-driven changes to lamin A phosphorylation and protein structure was performed using machine learning methods. Some of the predictions we generated were validated via assessment of ectopically expressed wild-type and mutant LMNA. Our findings indicate phenotype- and mutant-specific alterations in lamin phosphorylation, and that some changes in phosphorylation may occur independently of predicted changes in lamin protein structure. Therefore, therapeutic targeting of phosphorylation in the context of laminopathies will likely require mutant- and kinase-specific approaches.


Assuntos
Estudos de Associação Genética , Genótipo , Lamina Tipo A/genética , Laminopatias/patologia , Mutação , Fenótipo , Feminino , Humanos , Lamina Tipo A/metabolismo , Laminopatias/classificação , Laminopatias/genética , Laminopatias/metabolismo , Masculino , Fosforilação
14.
Soft Matter ; 17(9): 2512-2517, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33506846

RESUMO

There is hitherto a lack of a simple way to disrupt the coating of particles from liquid marbles in order to introduce additional reagents. Here, a 40 µL liquid marble, created on a superhydrophobic substrate with a 2 mm hole, forms an overhead and overhanging liquid component from which a single gas bubble of up to 28 µL volume could be introduced via the latter. This caused a localized clearing of the particle shell at the apical region of the overhead component because the particles could not be energetically sustained at the thin film region of the bubble. The subsequent dispensation of 5 µL of an external liquid directly onto the shell-free apex of the liquid marble allowed the coalescence of the two liquid bodies, bubble rupture, and restoration of complete particle shell encapsulation. The addition of the liquid via the overhanging component was alternatively found incapable of increasing the size of the overhead drop component. The localized bubble-actuated transient shell clearance at the apex of the liquid marble to allow the addition of reagents shown here portends new vistas for liquid marbles to be used in biomedical applications.

15.
Am J Physiol Heart Circ Physiol ; 319(2): H251-H261, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32559136

RESUMO

Human ether-à-go-go related gene (hERG) K+ channels are important in cardiac repolarization, and their dysfunction causes prolongation of the ventricular action potential, long QT syndrome, and arrhythmia. As such, approaches to augment hERG channel function, such as activator compounds, have been of significant interest due to their marked therapeutic potential. Activator compounds that hinder channel inactivation abbreviate action potential duration (APD) but carry risk of overcorrection leading to short QT syndrome. Enhanced risk by overcorrection of the APD may be tempered by activator-induced increased refractoriness; however, investigation of the cumulative effect of hERG activator compounds on the balance of these effects in whole organ systems is lacking. Here, we have investigated the antiarrhythmic capability of a hERG activator, RPR260243, which primarily augments channel function by slowing deactivation kinetics in ex vivo zebrafish whole hearts. We show that RPR260243 abbreviates the ventricular APD, reduces triangulation, and steepens the slope of the electrical restitution curve. In addition, RPR260243 increases the post-repolarization refractory period. We provide evidence that this latter effect arises from RPR260243-induced enhancement of hERG channel-protective currents flowing early in the refractory period. Finally, the cumulative effect of RPR260243 on arrhythmogenicity in whole organ zebrafish hearts is demonstrated by the restoration of normal rhythm in hearts presenting dofetilide-induced arrhythmia. These findings in a whole organ model demonstrate the antiarrhythmic benefit of hERG activator compounds that modify both APD and refractoriness. Furthermore, our results demonstrate that targeted slowing of hERG channel deactivation and enhancement of protective currents may provide an effective antiarrhythmic approach.NEW & NOTEWORTHY hERG channel dysfunction causes long QT syndrome and arrhythmia. Activator compounds have been of significant interest due to their therapeutic potential. We used the whole organ zebrafish heart model to demonstrate the antiarrhythmic benefit of the hERG activator, RPR260243. The activator abbreviated APD and increased refractoriness, the combined effect of which rescued induced ventricular arrhythmia. Our findings show that the targeted slowing of hERG channel deactivation and enhancement of protective currents caused by the RPR260243 activator may provide an effective antiarrhythmic approach.


Assuntos
Antiarrítmicos/farmacologia , Arritmias Cardíacas/prevenção & controle , Canal de Potássio ERG1/agonistas , Canais de Potássio Éter-A-Go-Go/agonistas , Frequência Cardíaca/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Piperidinas/farmacologia , Quinolinas/farmacologia , Proteínas de Peixe-Zebra/agonistas , Potenciais de Ação , Animais , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/fisiopatologia , Modelos Animais de Doenças , Canal de Potássio ERG1/genética , Canal de Potássio ERG1/metabolismo , Canais de Potássio Éter-A-Go-Go/metabolismo , Cinética , Miócitos Cardíacos/metabolismo , Oócitos , Período Refratário Eletrofisiológico , Transdução de Sinais , Xenopus laevis , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
16.
Anal Biochem ; 608: 113906, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32795454

RESUMO

Dry ice (solid CO2) remains highly useful when temperature-sensitive biological samples need to be cryogenically transported. CO2 released during the sublimation of dry ice can diffuse through gas permeable receptacle material or any defective seals resulting in potential sample acidification and compromised integrity. In addition, the quality of cryopreservation can be undermined once the dry ice is exhausted. The dry ice carrier design described here has been demonstrated to prevent sublimated CO2 from reaching the samples while maintaining storage temperature below -60 °C for 19 h. It is also equipped with microcontroller-based temperature monitoring for traceability and CO2 gas monitoring for safety.


Assuntos
Criopreservação/instrumentação , Criopreservação/métodos , Desenho de Equipamento , Dióxido de Carbono/análise , Temperatura Baixa , Gelo-Seco , Humanos , Concentração de Íons de Hidrogênio , Sublimação Química , Fatores de Tempo , Meios de Transporte
17.
PLoS Genet ; 13(8): e1006938, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28787442

RESUMO

Advances in genomics in recent years have provided key insights into defining cancer subtypes "within-a-tissue"-that is, respecting traditional anatomically driven divisions of medicine. However, there remains a dearth of data regarding molecular profiles that are shared across tissues, an understanding of which could lead to the development of highly versatile, broadly applicable therapies. Using data acquired from The Cancer Genome Atlas (TCGA), we performed a transcriptomics-centered analysis on 1494 patient samples, comparing the two major histological subtypes of solid tumors (adenocarcinomas and squamous cell carcinomas) across organs, with a focus on tissues in which both subtypes arise: esophagus, lung, and uterine cervix. Via principal component and hierarchical clustering analysis, we discovered that histology-driven differences accounted for a greater degree of inherent molecular variation in the tumors than did tissue of origin. We then analyzed differential gene expression, DNA methylation, and non-coding RNA expression between adenocarcinomas and squamous cell carcinomas and found 1733 genes, 346 CpG sites, and 42 microRNAs in common between organ sites, indicating specific adenocarcinoma-associated and squamous cell carcinoma-associated molecular patterns that were conserved across tissues. We then identified specific pathways that may be critical to the development of adenocarcinomas and squamous cell carcinomas, including Liver X receptor activation, which was upregulated in adenocarcinomas but downregulated in squamous cell carcinomas, possibly indicating important differences in cancer cell metabolism between these two histological subtypes of cancer. In addition, we highlighted genes that may be common drivers of adenocarcinomas specifically, such as IGF2BP1, which suggests a possible link between embryonic development and tumor subtype. Altogether, we demonstrate the need to consider biological similarities that transcend anatomical boundaries to inform the development of novel therapeutic strategies. All data sets from our analysis are available as a resource for further investigation.


Assuntos
Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Regulação Neoplásica da Expressão Gênica , Transcriptoma , Adenocarcinoma/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Colo do Útero/patologia , Metilação de DNA , Regulação para Baixo , Epigenômica , Esôfago/patologia , Feminino , Marcadores Genéticos , Variação Genética , Humanos , Receptores X do Fígado/genética , Receptores X do Fígado/metabolismo , Pulmão/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Análise de Componente Principal , Prognóstico , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Reprodutibilidade dos Testes , Regulação para Cima
18.
Mil Psychol ; 32(6): 389-407, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-38536388

RESUMO

The importance of leadership to organizational performance puts a premium on identifying future leaders. Early prediction of high-potential talent enables organizations to marshal scarce developmental resources and opportunities to those who are best positioned to show distinction in elevated roles. Much of the existing literature indicates that general mental ability remains the strongest predictor of future professional performance. Using data from 13 classes of West Point graduates who stayed in the Army to be considered for at least early promotion to the rank of major (N = 5,505), regression analyses indicate that cadet military grade point average surpasses both cognitive ability and academic performance by a considerable margin in the ability to predict future professional outcomes such as selection for early promotion or battalion command. Moreover, these differences in predicting managerial career outcomes endure over 16 years. Both practical and theoretical implications are discussed.

19.
Breast Cancer Res Treat ; 178(2): 307-316, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31420779

RESUMO

PURPOSE: The detection rate of breast ductal carcinoma in situ (DCIS) has increased significantly, raising the concern that DCIS is overdiagnosed and overtreated. Therefore, there is an unmet clinical need to better predict the risk of progression among DCIS patients. Our hypothesis is that by combining molecular signatures with clinicopathologic features, we can elucidate the biology of breast cancer progression, and risk-stratify patients with DCIS. METHODS: Targeted exon sequencing with a custom panel of 223 genes/regions was performed for 125 DCIS cases. Among them, 60 were from cases having concurrent or subsequent invasive breast cancer (IBC) (DCIS + IBC group), and 65 from cases with no IBC development over a median follow-up of 13 years (DCIS-only group). Copy number alterations in chromosome 1q32, 8q24, and 11q13 were analyzed using fluorescence in situ hybridization (FISH). Multivariable logistic regression models were fit to the outcome of DCIS progression to IBC as functions of demographic and clinical features. RESULTS: We observed recurrent variants of known IBC-related mutations, and the most commonly mutated genes in DCIS were PIK3CA (34.4%) and TP53 (18.4%). There was an inverse association between PIK3CA kinase domain mutations and progression (Odds Ratio [OR] 10.2, p < 0.05). Copy number variations in 1q32 and 8q24 were associated with progression (OR 9.3 and 46, respectively; both p < 0.05). CONCLUSIONS: PIK3CA kinase domain mutations and the absence of copy number gains in DCIS are protective against progression to IBC. These results may guide efforts to distinguish low-risk from high-risk DCIS.


Assuntos
Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Estudo de Associação Genômica Ampla , Genômica , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal de Mama/terapia , Variações do Número de Cópias de DNA , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Humanos , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Carga Tumoral
20.
Annu Rev Biomed Eng ; 20: 329-352, 2018 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-29539267

RESUMO

Metastasis contributes to poor prognosis in many types of cancer and is the leading cause of cancer-related deaths. Tumor cells metastasize to distant sites via the circulatory and lymphatic systems. In this review, we discuss the potential of circulating tumor cells for diagnosis and describe the experimental therapeutics that aim to target these disseminating cancer cells. We discuss the advantages and limitations of such strategies and how they may lead to the development of the next generation of antimetastasis treatments.


Assuntos
Neoplasias/sangue , Neoplasias/diagnóstico , Células Neoplásicas Circulantes/patologia , Animais , Separação Celular , Eletroforese , Células Epiteliais/citologia , Filtração , Humanos , Dispositivos Lab-On-A-Chip , Linfonodos/patologia , Metástase Linfática , Sistema Linfático/fisiologia , Metástase Neoplásica , Prognóstico , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
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