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1.
J Dual Diagn ; : 1-9, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38555875

RESUMO

Objective: The present study examines the network structure and, using Bayesian network analysis, estimates the directional pathways among symptoms of posttraumatic stress disorder (PTSD), major depressive disorder (MDD), and levels of alcohol and cannabis use. Method: A sample of 1471 adults in the United States, who reported at least one potentially traumatic event, completed the PTSD Checklist (PCL-5), Patient Health Questionnaire (PHQ-9), and the Alcohol/Cannabis Use Disorders Identification Test (AUDIT/CUDIT). A regularized partial correlation network provided estimates of symptoms clusters and connections. Directional pathways within the network were then estimated using a directed acyclic graph (DAG). Results: Symptoms clustered in theoretically consistent ways. Risky behavior demonstrated the highest strength centrality and bridge strength. Neither alcohol nor cannabis use appeared central in the network, and DAG results suggested that MDD and PTSD symptoms are more likely to lead to substance use than the other way around. Conclusions: Results suggest that cannabis use is largely connected to alcohol use. Consistent with prior research, risky behavior appeared to be the primary bridge between substance use and PTSD. The direction of associations between substance use and psychological symptoms requires further attention.

2.
J Diabetes Investig ; 15(3): 263-274, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38193815

RESUMO

Overconsumption of energy-rich foods that disrupt caloric balance is a fundamental cause of overweight, obesity and diabetes. Dysglycemia and the resulting cardiovascular disease cause substantial morbidity and mortality worldwide, as well as high societal cost. The prevalence of obesity in childhood and adolescence is increasing, leading to younger diabetes diagnosis, and higher severity of microvascular and macrovascular complications. An important goal is to identify early life conditions that increase future metabolic risk, toward the goal of preventing diabetes and cardiovascular disease. An ample body of evidence implicates prenatal and postnatal childhood growth trajectories in the programming of adult metabolic disease. Human epidemiological data show that accelerated childhood growth increases risk of type 2 diabetes in adulthood. Type 2 diabetes results from the combination of insulin resistance and pancreatic ß-cell failure, but specific mechanisms by which accelerated postnatal growth impact one or both of these processes remain uncertain. This review explores the metabolic impact of overnutrition during postnatal life in humans and in rodent models, with specific attention to the connection between accelerated childhood growth and future adiposity, insulin resistance, ß-cell mass and ß-cell dysfunction. With improved knowledge in this area, we might one day be able to modulate nutrition and growth in the critical postnatal window to maximize lifelong metabolic health.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Hipernutrição , Obesidade Infantil , Adolescente , Adulto , Feminino , Gravidez , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Hipernutrição/complicações
3.
mBio ; 14(1): e0258922, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36645302

RESUMO

Many bacteria of the genus Shewanella are facultative anaerobes able to reduce a broad range of soluble and insoluble substrates, including Fe(III) mineral oxides. Under anoxic conditions, the bacterium Shewanella oneidensis MR-1 uses a porin-cytochrome complex (Mtr) to mediate extracellular electron transfer (EET) across the outer membrane to extracellular substrates. However, it is unclear how EET prevents generating harmful reactive oxygen species (ROS) when exposed to oxic environments. The Mtr complex is expressed under anoxic and oxygen-limited conditions and contains an extracellular MtrC subunit. This has a conserved CX8C motif that inhibits aerobic growth when removed. This inhibition is caused by an increase in ROS that kills the majority of S. oneidensis cells in culture. To better understand this effect, soluble MtrC isoforms with modified CX8C were isolated. These isoforms produced increased concentrations of H2O2 in the presence of flavin mononucleotide (FMN) and greatly increased the affinity between MtrC and FMN. X-ray crystallography revealed that the molecular structure of MtrC isoforms was largely unchanged, while small-angle X-ray scattering suggested that a change in flexibility was responsible for controlling FMN binding. Together, these results reveal that FMN reduction in S. oneidensis MR-1 is controlled by the redox-active disulfide on the cytochrome surface. In the presence of oxygen, the disulfide forms, lowering the affinity for FMN and decreasing the rate of peroxide formation. This cysteine pair consequently allows the cell to respond to changes in oxygen level and survive in a rapidly transitioning environment. IMPORTANCE Bacteria that live at the oxic/anoxic interface have to rapidly adapt to changes in oxygen levels within their environment. The facultative anaerobe Shewanella oneidensis MR-1 can use EET to respire in the absence of oxygen, but on exposure to oxygen, EET could directly reduce extracellular oxygen and generate harmful reactive oxygen species that damage the bacterium. By modifying an extracellular cytochrome called MtrC, we show how preventing a redox-active disulfide from forming causes the production of cytotoxic concentrations of peroxide. The disulfide affects the affinity of MtrC for the redox-active flavin mononucleotide, which is part of the EET pathway. Our results demonstrate how a cysteine pair exposed on the surface controls the path of electron transfer, allowing facultative anaerobic bacteria to rapidly adapt to changes in oxygen concentration at the oxic/anoxic interface.


Assuntos
Cisteína , Shewanella , Espécies Reativas de Oxigênio/metabolismo , Cisteína/metabolismo , Compostos Férricos/metabolismo , Mononucleotídeo de Flavina/metabolismo , Peróxido de Hidrogênio/metabolismo , Oxirredução , Citocromos/metabolismo , Transporte de Elétrons , Shewanella/genética , Shewanella/metabolismo , Flavinas/metabolismo , Oxigênio/metabolismo , Dissulfetos/metabolismo
4.
Development ; 149(19)2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36189829

RESUMO

MicroRNAs (miRs) have an important role in tuning dynamic gene expression. However, the mechanism by which they are quantitatively controlled is unknown. We show that the amount of mature miR-9, a key regulator of neuronal development, increases during zebrafish neurogenesis in a sharp stepwise manner. We characterize the spatiotemporal profile of seven distinct microRNA primary transcripts (pri-mir)-9s that produce the same mature miR-9 and show that they are sequentially expressed during hindbrain neurogenesis. Expression of late-onset pri-mir-9-1 is added on to, rather than replacing, the expression of early onset pri-mir-9-4 and -9-5 in single cells. CRISPR/Cas9 mutation of the late-onset pri-mir-9-1 prevents the developmental increase of mature miR-9, reduces late neuronal differentiation and fails to downregulate Her6 at late stages. Mathematical modelling shows that an adaptive network containing Her6 is insensitive to linear increases in miR-9 but responds to stepwise increases of miR-9. We suggest that a sharp stepwise increase of mature miR-9 is created by sequential and additive temporal activation of distinct loci. This may be a strategy to overcome adaptation and facilitate a transition of Her6 to a new dynamic regime or steady state.


Assuntos
MicroRNAs , Peixe-Zebra , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Neurogênese/genética , Peixe-Zebra/metabolismo
5.
PLoS Comput Biol ; 18(9): e1010406, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36067224

RESUMO

The first year of the COVID-19 pandemic put considerable strain on healthcare systems worldwide. In order to predict the effect of the local epidemic on hospital capacity in England, we used a variety of data streams to inform the construction and parameterisation of a hospital progression model, EpiBeds, which was coupled to a model of the generalised epidemic. In this model, individuals progress through different pathways (e.g. may recover, die, or progress to intensive care and recover or die) and data from a partially complete patient-pathway line-list was used to provide initial estimates of the mean duration that individuals spend in the different hospital compartments. We then fitted EpiBeds using complete data on hospital occupancy and hospital deaths, enabling estimation of the proportion of individuals that follow the different clinical pathways, the reproduction number of the generalised epidemic, and to make short-term predictions of hospital bed demand. The construction of EpiBeds makes it straightforward to adapt to different patient pathways and settings beyond England. As part of the UK response to the pandemic, EpiBeds provided weekly forecasts to the NHS for hospital bed occupancy and admissions in England, Wales, Scotland, and Northern Ireland at national and regional scales.


Assuntos
COVID-19 , COVID-19/epidemiologia , Inglaterra/epidemiologia , Hospitalização , Hospitais , Humanos , Pandemias
6.
Front Oncol ; 12: 892043, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35774118

RESUMO

Patients who develop testicular germ cell tumours (TGCT) are at higher risk to be subfertile than the general population. The conditions are believed to originate during foetal life, however, the mechanisms behind a common aetiology of TGCT and male subfertility remains unknown. Testis-expressed 101 (TEX101) is a glycoprotein that is related to male fertility, and downregulation of the TEX101 gene was shown in pre-diagnostic TGCT patients. In this review, we summarize the current knowledge of TEX101 and its interactome related to fertility and TGCT development. We searched literature and compilation of data from curated databases. There are studies from both human and animals showing that disruption of TEX101 result in abnormal semen parameters and sperm function. Members of the TEX101 interactome, like SPATA19, Ly6k, PICK1, and ODF genes are important for normal sperm function. We found only two studies of TEX101 related to TGCT, however, several genes in its interactome may be associated with TGCT development, such as PLAUR, PRSS21, CD109, and ALP1. Some of the interactome members are related to both fertility and cancer. Of special interest is the presence of the glycosylphosphatidylinositol anchored proteins TEX101 and PRSS21 in basophils that may be coupled to the immune response preventing further development of TGCT precursor cells. The findings of this review indicate that members of the TEX101 interactome could be a part of the link between TGCT and male subfertility.

7.
J Med Syst ; 46(6): 34, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35511408

RESUMO

Digital health tools (DHT) are increasingly poised to change healthcare delivery given the Coronavirus Disease 2019 (COVID-19) pandemic and the drive to telehealth. Establishing the potential utility of a given DHT could aid in identifying how it could be best used and further opportunities for healthcare improvement. We propose a metric, a Utility Factor Score, which quantifies the benefits of a DHT by explicitly defining adherence and linking it directly to satisfaction and health goals met. To provide data for how the comparative utility score can or should work, we illustrate in detail the application of our metrics across four DHTs with two simulated users. The Utility Factor Score can potentially facilitate integration of DHTs into various healthcare settings and should be evaluated within a clinical study.


Assuntos
COVID-19 , Telemedicina , Atenção à Saúde , Humanos , Pandemias
8.
Biol Reprod ; 106(3): 515-525, 2022 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-34725674

RESUMO

Cell signaling mediated by the KIT receptor is critical for many aspects of oogenesis including the proliferation and migration of primordial germ cells, as well as the survival, growth, and maturation of ovarian follicles. We previously showed that KIT regulates cyst breakdown and primordial follicle formation, and in this study, have investigated the mechanisms downstream of the receptor by modulating the activity of two downstream signaling cascades: the phosphoinositide 3-kinase (PI3K) and the mitogen-activated protein kinase pathways. E17.5 ovaries were cultured for 5 days with a daily dose of media supplemented with either the PI3K inhibitor LY294002, the MEK inhibitor U0126, or a DMSO vehicle control. Our histological observations aligned with the established role of PI3K in oocyte growth and primordial follicle activation but also revealed that LY294002 treatment delayed the processes of cyst breakdown and primordial follicle formation. U0126 treatment also led to a reduction in oocyte growth and follicle development but did not appear to affect cyst breakdown. The delay in cyst breakdown was mitigated when ovaries were dually dosed with LY294002 and KITL, suggesting that while KIT may signal through PI3K to promote cyst breakdown, other signaling networks downstream of the receptor could compensate. These observations unearth a role for PI3K signaling in the establishment of the ovarian reserve and suggest that PI3K might be the primary mediator of KIT-induced cyst breakdown and primordial follicle formation in the mouse ovary.


Assuntos
Cistos , Fosfatidilinositol 3-Quinases , Animais , Cistos/metabolismo , Feminino , Camundongos , Oócitos/metabolismo , Folículo Ovariano/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/fisiologia
9.
J R Soc Interface ; 18(182): 20210393, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34583566

RESUMO

Gene expression dynamics, such as stochastic oscillations and aperiodic fluctuations, have been associated with cell fate changes in multiple contexts, including development and cancer. Single cell live imaging of protein expression with endogenous reporters is widely used to observe such gene expression dynamics. However, the experimental investigation of regulatory mechanisms underlying the observed dynamics is challenging, since these mechanisms include complex interactions of multiple processes, including transcription, translation and protein degradation. Here, we present a Bayesian method to infer kinetic parameters of oscillatory gene expression regulation using an auto-negative feedback motif with delay. Specifically, we use a delay-adapted nonlinear Kalman filter within a Metropolis-adjusted Langevin algorithm to identify posterior probability distributions. Our method can be applied to time-series data on gene expression from single cells and is able to infer multiple parameters simultaneously. We apply it to published data on murine neural progenitor cells and show that it outperforms alternative methods. We further analyse how parameter uncertainty depends on the duration and time resolution of an imaging experiment, to make experimental design recommendations. This work demonstrates the utility of parameter inference on time course data from single cells and enables new studies on cell fate changes and population heterogeneity.


Assuntos
Algoritmos , Regulação da Expressão Gênica , Animais , Teorema de Bayes , Cinética , Camundongos , Probabilidade
11.
Hum Immunol ; 82(4): 232-239, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33692011

RESUMO

BACKGROUNDS: Genetic polymorphism of the toll-like receptor 2, 4 (TLR2, TLR4) and natural resistance-associated macrophage protein 1 (NRAMP1) genes may affect host immune response to Mycobacterium tuberculosis (Mtb) and lead to the variation of susceptibility to tuberculosis (TB) in humans. However, the association of single nucleotide polymorphisms (SNP) in these genes and the susceptibility to TB in Mongolian population has not been investigated. METHODS: We conducted a genetic association study including 197 Mongolian TB patients and 217 Mongolian healthy controls in Inner Mongolia, China. DNA of blood samples was extracted and genotyped for 5 SNPs in TLR4, 4 SNPs in TLR2 and 5 SNPs in NRAMP1 by next-generation sequencing. A logistic regression was performed and odds ratios (OR) with 95% confidence intervals (CI) were calculated to estimate the risk at TB by each SNP. RESULTS: The most significant locus associated with the susceptibility to TB was TLR4 rs11536889. The frequency for allele C of TLR4 rs11536889 was 16.0% in TB patients and 23.5% in healthy controls, respectively. Rs11536889 C/C genotype of TLR4 was significantly associated with the low susceptibility against TB compared to G/G genotype in the dominant model (OR 0.62, 95% CI 0.41-0.94). CONCLUSIONS: The TLR4 rs11536889 polymorphisms might be an indicative of the low susceptibility to TB in Mongolian population, which provides valuable information for the generation of effective strategy or measurement against TB in Mongolian population.


Assuntos
Proteínas de Transporte de Cátions/genética , Genótipo , Mycobacterium tuberculosis/fisiologia , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Tuberculose Pulmonar/genética , Adulto , Estudos de Casos e Controles , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Imunidade Inata/genética , Masculino , Pessoa de Meia-Idade , Mongólia/epidemiologia , Polimorfismo de Nucleotídeo Único , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/imunologia
12.
Front Oncol ; 10: 574977, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33251139

RESUMO

Although testicular germ cell tumor (TGCT) overall is highly curable, patients may experience late effects after treatment. An increased understanding of the mechanisms behind the development of TGCT may pave the way for better outcome for patients. To elucidate molecular changes prior to TGCT diagnosis we sequenced small RNAs in serum from 69 patients who were later diagnosed with TGCT and 111 matched controls. The deep RNA profiles, with on average 18 million sequences per sample, comprised of nine classes of RNA, including microRNA. We found that circulating RNA signals differed significantly between cases and controls regardless of time to diagnosis. Different levels of TSIX related to X-chromosome inactivation and TEX101 involved in spermatozoa production are among the interesting findings. The RNA signals differed between seminoma and non-seminoma TGCT subtypes, with seminoma cases showing lower levels of RNAs and non-seminoma cases showing higher levels of RNAs, compared with controls. The differentially expressed RNAs were typically associated with cancer related pathways. Our results indicate that circulating RNA profiles change during TGCT development according to histology and may be useful for early detection of this tumor type.

13.
Invest Ophthalmol Vis Sci ; 61(1): 4, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31999819

RESUMO

Purpose: Neurotrophic keratopathy is a degenerative disease that may be improved by nerve growth factor (NGF). Our aim was to investigate the use of pergolide, a dopamine (D1 and D2) receptor agonist known to increase the synthesis and release of NGF for regeneration of damaged corneal nerve fibers. Methods: Pergolide function was evaluated by measuring axon length and NGF levels by enzyme-linked immunosorbent assay in cultured chicken dorsal root ganglion (DRG) cells with serial doses of pergolide (10, 25, 50, 150, and 300 µg/ml) and with different concentrations of a D1 antagonist. Pergolide function was further evaluated by cornea nerve fiber density and wound healing in a cornea scratch mouse model. Results: Pergolide increased DRG axon length significantly at a dose between 50 and 300 µg/ml. Different concentrations of D1 antagonist (12, 24, 48, and 96 µg/ml) inhibited DRG axon length growth with pergolide (300 µg/ml). Pergolide (50 µg/ml) upregulated NGF expression in DRG cells at both 24 hours and 48 hours. Pergolide improved cornea nerve fiber density at both 1 week and 2 weeks. Pergolide also improved cornea wound healing. Conclusions: We demonstrated that pergolide can act to promote an increase in NGF which promotes corneal nerve regeneration and would therefore improve corneal sensation and visual acuity in eyes with peripheral neurotrophic keratopathy.


Assuntos
Lesões da Córnea/tratamento farmacológico , Agonistas de Dopamina/uso terapêutico , Fibras Nervosas/efeitos dos fármacos , Pergolida/uso terapêutico , Animais , Axônios/efeitos dos fármacos , Galinhas , Agonistas de Dopamina/farmacologia , Gânglios Espinais/efeitos dos fármacos , Camundongos , Regeneração Nervosa , Pergolida/farmacologia , Cicatrização/fisiologia
14.
Genome Biol Evol ; 11(12): 3353-3371, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31702783

RESUMO

The genus Rhododendron (Ericaceae), which includes horticulturally important plants such as azaleas, is a highly diverse and widely distributed genus of >1,000 species. Here, we report the chromosome-scale de novo assembly and genome annotation of Rhododendron williamsianum as a basis for continued study of this large genus. We created multiple short fragment genomic libraries, which were assembled using ALLPATHS-LG. This was followed by contiguity preserving transposase sequencing (CPT-seq) and fragScaff scaffolding of a large fragment library, which improved the assembly by decreasing the number of scaffolds and increasing scaffold length. Chromosome-scale scaffolding was performed by proximity-guided assembly (LACHESIS) using chromatin conformation capture (Hi-C) data. Chromosome-scale scaffolding was further refined and linkage groups defined by restriction-site associated DNA (RAD) sequencing of the parents and progeny of a genetic cross. The resulting linkage map confirmed the LACHESIS clustering and ordering of scaffolds onto chromosomes and rectified large-scale inversions. Assessments of the R. williamsianum genome assembly and gene annotation estimate them to be 89% and 79% complete, respectively. Predicted coding sequences from genome annotation were used in syntenic analyses and for generating age distributions of synonymous substitutions/site between paralgous gene pairs, which identified whole-genome duplications (WGDs) in R. williamsianum. We then analyzed other publicly available Ericaceae genomes for shared WGDs. Based on our spatial and temporal analyses of paralogous gene pairs, we find evidence for two shared, ancient WGDs in Rhododendron and Vaccinium (cranberry/blueberry) members that predate the Ericaceae family and, in one case, the Ericales order.


Assuntos
Cromossomos de Plantas/genética , Ericaceae/genética , Genoma de Planta/genética , Rhododendron/genética , Sintenia , Sequência de Bases , Cromatina/genética , Mapeamento Cromossômico , Ligação Genética , Biblioteca Genômica , Anotação de Sequência Molecular , Transposases/genética
15.
Muscle Nerve ; 60(5): 613-620, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31397908

RESUMO

INTRODUCTION: The objective of this study is to assess the efficacy of local tacrolimus (FK506) delivery to improve outcomes in the setting of nerve transection injury. METHODS: FK506 embedded poly(lactide-co-caprolactone) films capable of extended, localized release of FK506 were developed. FK506 rate of release testing and bioactivity assay was performed. Mouse sciatic nerve transection and direct repair model was used to evaluate the effect extended, local delivery of FK506 had on nerve regeneration outcomes. RESULTS: Linear release of FK506 was observed for 30 days and released FK506 matched control levels of neurite extension in the dorsal root ganglion assay. Groups treated with local FK506 had greater gastrocnemius muscle weight, foot electromyogram, and number of axons distal of the repair site than non-FK506 groups. DISCUSSION: Results of this study indicate that extended, localized delivery of FK506 to nerve injuries can improve nerve regeneration outcomes in a mouse sciatic nerve transection and repair.


Assuntos
Imunossupressores/farmacologia , Denervação Muscular , Músculo Esquelético/efeitos dos fármacos , Regeneração Nervosa/efeitos dos fármacos , Nervo Isquiático/lesões , Tacrolimo/farmacologia , Animais , Axônios/efeitos dos fármacos , Axônios/patologia , Preparações de Ação Retardada , Eletromiografia , Gânglios Espinais/efeitos dos fármacos , Imunossupressores/administração & dosagem , Camundongos , Músculo Esquelético/patologia , Neuritos/efeitos dos fármacos , Neuritos/patologia , Procedimentos Neurocirúrgicos , Tamanho do Órgão , Traumatismos dos Nervos Periféricos , Poliésteres , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/patologia , Nervo Isquiático/cirurgia , Tacrolimo/administração & dosagem
16.
Adv Skin Wound Care ; 32(7S Suppl 1): S14-S20, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31219897

RESUMO

It has been demonstrated that wound dressings provide a protective effect against pressure injuries. However, no method exists to measure either the life or performance of dressings used in prevention; testing dressings in a clinical setting or a research environment has typically been based on measuring its moisture absorption capacity. This article examines the changes that occur in the structural and mechanical properties of a prophylactic dressing based on conditions of use when wound exudate is not present.A clinically relevant method was developed to simulate the loading, friction-inducing shear, and moisture transpiration present in a typical hospitalization where a dressing is applied for prevention. Single-use dressings were tested using this method to evaluate their ability to protect patients from pressure injuries throughout the typical 5 to 7 days of use. Following this aging process, researchers measured the physical, structural, and mechanical changes in prophylactic dressings over time.This innovative method provides guidance for clinicians on dressing use and replacement intervals. For bioengineers, the method generates important empirical data for computer modeling of dressing performance, which can then reveal the consequences of changes in dressing structure and function on sustained tissue loads. It is the authors' hope to generate discussion about the creation of industry-wide standards for testing dressings to improve patient care.


Assuntos
Bandagens , Teste de Materiais , Úlcera por Pressão/prevenção & controle , Sacro , Desenho de Equipamento , Humanos
17.
Adv Skin Wound Care ; 32(7S Suppl 1): S21-S27, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31219898

RESUMO

Results from large-scale randomized clinical trials support the application of prophylactic dressings to provide protection from body-weight force-induced deformations known to damage skin and underlying tissues, which often result in pressure injuries (pressure ulcers). This laboratory study using a new method for aging dressings in simulated use followed by tensile testing was conducted to further understand the protective effect of sacral prophylactic dressings (SPDs) in alleviating tissue deformations in the sacral region through the course of typical application. Specifically, four SPDs were exposed to a simulation of the clinical environment incorporating saline solution absorption, mechanical loading, and repetitive sliding-induced shear. After aging, the protective endurance of the SPDs was measured through tensile testing to determine their effectiveness against tissue-damaging forces over time.This study uses the concepts of axial stiffness, protective endurance, and elastic limit to describe more accurately the protective aspects of SPDs under dry and moist conditions and how they interact with the skin and underlying tissues over the life of the dressing. The authors propose two primary features in SPD effectiveness in preventing pressure injuries: high conformability (ie, low flexural stiffness) and protective endurance (the dressing's capacity to maintain biomechanical performance when moist).


Assuntos
Bandagens , Teste de Materiais , Úlcera por Pressão/prevenção & controle , Sacro , Resistência à Tração , Desenho de Equipamento , Humanos , Fatores de Tempo , Suporte de Carga
18.
Chronobiol Int ; 35(6): 849-852, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29737881

RESUMO

This study assessed sleep quality, sleepiness and use of workplace break opportunities in 1285 health-care workers via an online questionnaire. Two hospitals were surveyed - one with and one without a fatigue mitigation policy. Across all respondents, 68.9% reported generally taking breaks of at least 30 min and 21.7% had access to a quiet place to rest, with no significant differences between hospitals. The presence of a fatigue mitigation policy was not associated with reduced sleepiness. However, accounting for hospital and shift characteristics, employees with access to a quiet place to rest while on break had significantly lower self-reported sleepiness scores.


Assuntos
Ritmo Circadiano/fisiologia , Sonolência , Vigília/fisiologia , Local de Trabalho/psicologia , Adulto , Estudos Transversais , Feminino , Hospitais/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Sono/fisiologia , Transtornos do Sono do Ritmo Circadiano/fisiopatologia , Estados Unidos , Tolerância ao Trabalho Programado
19.
Yeast ; 35(1): 71-84, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28892574

RESUMO

Interspecific hybridization is a common mechanism enabling genetic diversification and adaptation; however, the detection of hybrid species has been quite difficult. The identification of microbial hybrids is made even more complicated, as most environmental microbes are resistant to culturing and must be studied in their native mixed communities. We have previously adapted the chromosome conformation capture method Hi-C to the assembly of genomes from mixed populations. Here, we show the method's application in assembling genomes directly from an uncultured, mixed population from a spontaneously inoculated beer sample. Our assembly method has enabled us to de-convolute four bacterial and four yeast genomes from this sample, including a putative yeast hybrid. Downstream isolation and analysis of this hybrid confirmed its genome to consist of Pichia membranifaciens and that of another related, but undescribed, yeast. Our work shows that Hi-C-based metagenomic methods can overcome the limitation of traditional sequencing methods in studying complex mixtures of genomes. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Cerveja/microbiologia , Hibridização Genética , Metagenômica/métodos , Leveduras/genética , Genoma Fúngico , Filogenia
20.
J Tissue Viability ; 26(3): 172-179, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28532968

RESUMO

Off-loading or the Orthotic approach to wheelchair seating has been used successfully to provide seating that optimizes tissue protection at the ischial tuberosities (ITs), sacrum and greater trochanters. Recent publications indicate the significance of preventing tissue compression to reduce ulcer formation. Comparative Magnetic Resonance Imaging (MRI) of individuals seated on two cushion types provides direct evidence of tissue unloading resulting in the reduction in tissue compression. Measurement of tissue compression in MRI images provides the cumulative impact of compression and shear resulting in ultimate tissue thickness documented here. In this study's application of MRI to off-loading cushions (OLC), an alternate form of tissue protection was observed. Instead of incorporating immersion and envelopment, loads were transferred from high-risk areas, such as bony prominences, to lower risk soft tissues. This method shows both shearing and compression of load bearing tissues in seated individuals with the OLC in place. Tissue thickness measurements determined by MRI analysis indicate that the OLC provides greater reduction in tissue deformation than the air cell cushion (ACC). Deformation of tissues loaded by the OLC is not significantly different from the deformations seen with the ACC. This research represents the first reported use of MRI to document the comparative off-loading capabilities of two cushions and the resultant tissue compression and ulceration risk. While MRI analysis may not be incorporated in daily cushion prescription, this paper proposes a methodology in which MRI analysis of tissue deformation on comparative cushions allows the determination of best-case cushion selection for reduction of ischial pressure ulcer (PU) risk.


Assuntos
Imageamento por Ressonância Magnética/métodos , Úlcera por Pressão/prevenção & controle , Cadeiras de Rodas/efeitos adversos , Adulto , Desenho de Equipamento/métodos , Desenho de Equipamento/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão/efeitos adversos , Úlcera por Pressão/fisiopatologia , Pele/fisiopatologia , Transdutores de Pressão , Suporte de Carga/fisiologia
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