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1.
Plant Cell Environ ; 46(10): 3012-3022, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35822392

RESUMO

Plants have evolved to deal with different stresses during plant growth, relying on complex interactions or crosstalk between multiple signalling pathways in plant cells. In this sophisticated regulatory network, Ca2+ transients in the cytosol ([Ca2+ ]cyt ) act as major physiological signals to initiate appropriate responses. The CALCINEURIN B-LIKE PROTEIN (CBL)-CBL-INTERACTING PROTEIN KINASE (CIPK) network relays physiological signals characterised by [Ca2+ ]cyt transients during plant development and in response to environmental changes. Many studies are aimed at elucidating the role of the CBL-CIPK network in plant growth and stress responses. This review discusses the involvement of the CBL-CIPK pathways in two levels of crosstalk between plant development and stress adaptation: direct crosstalk through interaction with regulatory proteins, and indirect crosstalk through adaptation of correlated physiological processes that affect both plant development and stress responses. This review thus provides novel insights into the physiological roles of the CBL-CIPK network in plant growth and stress adaptation.


Assuntos
Arabidopsis , Proteínas Quinases , Proteínas Quinases/metabolismo , Proteínas de Plantas/metabolismo , Arabidopsis/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Desenvolvimento Vegetal
3.
Nature ; 542(7641): 307-312, 2017 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-28178233

RESUMO

Chenopodium quinoa (quinoa) is a highly nutritious grain identified as an important crop to improve world food security. Unfortunately, few resources are available to facilitate its genetic improvement. Here we report the assembly of a high-quality, chromosome-scale reference genome sequence for quinoa, which was produced using single-molecule real-time sequencing in combination with optical, chromosome-contact and genetic maps. We also report the sequencing of two diploids from the ancestral gene pools of quinoa, which enables the identification of sub-genomes in quinoa, and reduced-coverage genome sequences for 22 other samples of the allotetraploid goosefoot complex. The genome sequence facilitated the identification of the transcription factor likely to control the production of anti-nutritional triterpenoid saponins found in quinoa seeds, including a mutation that appears to cause alternative splicing and a premature stop codon in sweet quinoa strains. These genomic resources are an important first step towards the genetic improvement of quinoa.


Assuntos
Chenopodium quinoa/genética , Genoma de Planta/genética , Processamento Alternativo/genética , Diploide , Evolução Molecular , Pool Gênico , Anotação de Sequência Molecular , Mutação , Poliploidia , Saponinas/biossíntese , Análise de Sequência de DNA , Fatores de Transcrição/metabolismo
4.
Br J Sports Med ; 57(12): 789-797, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37316184

RESUMO

OBJECTIVE: Determine the role of fluid-based biomarkers, advanced neuroimaging, genetic testing and emerging technologies in defining and assessing neurobiological recovery after sport-related concussion (SRC). DESIGN: Systematic review. DATA SOURCES: Searches of seven databases from 1 January 2001 through 24 March 2022 using keywords and index terms relevant to concussion, sports and neurobiological recovery. Separate reviews were conducted for studies involving neuroimaging, fluid biomarkers, genetic testing and emerging technologies. A standardised method and data extraction tool was used to document the study design, population, methodology and results. Reviewers also rated the risk of bias and quality of each study. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Studies were included if they: (1) were published in English; (2) represented original research; (3) involved human research; (4) pertained only to SRC; (5) included data involving neuroimaging (including electrophysiological testing), fluid biomarkers or genetic testing or other advanced technologies used to assess neurobiological recovery after SRC; (6) had a minimum of one data collection point within 6 months post-SRC; and (7) contained a minimum sample size of 10 participants. RESULTS: A total of 205 studies met inclusion criteria, including 81 neuroimaging, 50 fluid biomarkers, 5 genetic testing, 73 advanced technologies studies (4 studies overlapped two separate domains). Numerous studies have demonstrated the ability of neuroimaging and fluid-based biomarkers to detect the acute effects of concussion and to track neurobiological recovery after injury. Recent studies have also reported on the diagnostic and prognostic performance of emerging technologies in the assessment of SRC. In sum, the available evidence reinforces the theory that physiological recovery may persist beyond clinical recovery after SRC. The potential role of genetic testing remains unclear based on limited research. CONCLUSIONS: Advanced neuroimaging, fluid-based biomarkers, genetic testing and emerging technologies are valuable research tools for the study of SRC, but there is not sufficient evidence to recommend their use in clinical practice. PROSPERO REGISTRATION NUMBER: CRD42020164558.


Assuntos
Concussão Encefálica , Humanos , Concussão Encefálica/diagnóstico , Biomarcadores , Coleta de Dados , Bases de Dados Factuais , Testes Genéticos
5.
Clin J Sport Med ; 33(2): 123-129, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36730735

RESUMO

OBJECTIVE: To provide preseason reference scores for Canadian youth tackle football players on the Sport Concussion Assessment Tool 5 (SCAT5) and to examine whether age, concussion history, and self-reported medical diagnoses are associated with SCAT5 subcomponent performance. DESIGN: Cross-sectional study. SETTING: Calgary, Alberta. PARTICIPANTS: Five hundred one male youth football players (ages 13-18 years) participating in the 2021 season. ASSESSMENT OF RISK FACTORS: SCAT5 subcomponents were assessed by age group (13-14, 15-16, 17-18), concussion history (0, 1, 2+, and yes/no), and self-reported diagnoses (headache disorder, attention-deficit/hyperactive disorder, learning disability/dyslexia, and depression, anxiety, or other psychiatric disorder). MAIN OUTCOME MEASURES: Virtual video administration (vs traditional in-person testing) of the SCAT5 was completed, and subcomponent scores included total number of symptoms (/22), symptom-severity score (/132), Standardized Assessment of Concussion [orientation (/5), immediate memory (/30), concentration (/5), delayed recall (/10)], and modified Balance Error Scoring System (/30). Kruskal-Wallis, one-way analysis of variance , Mann-Whitney U , or independent t tests were used to assess possible associations depending on number of groups and data normality. RESULTS: Virtual SCAT5 assessment scores across all outcomes did not differ by age group or concussion history. The median number of symptoms and median symptom-severity score at baseline was 2, and 173 players (34.5%) reported no symptoms. Median total number of errors on the modified Balance Error Scoring System was 3. Participants with certain self-reported diagnoses (attention-deficit/hyperactive disorder, dyslexia) demonstrated poorer performance on some SCAT5 subcomponents (symptom reporting, Standardized Assessment of Concussion). CONCLUSIONS: Baseline SCAT5 performance did not differ by age group or concussion history in male youth football players. Diagnoses of the self-reported disorders examined may be important considerations for interpretation of the SCAT5 assessment.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Futebol Americano , Humanos , Masculino , Adolescente , Futebol Americano/psicologia , Estudos Transversais , Testes Neuropsicológicos , Concussão Encefálica/complicações , Alberta , Traumatismos em Atletas/diagnóstico
6.
Am J Physiol Regul Integr Comp Physiol ; 321(6): R925-R937, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34730005

RESUMO

Previous research has highlighted that squat-stand maneuvers (SSMs) augment coherence values within the cerebral pressure-flow relationship to ∼0.99. However, it is not fully elucidated if mean arterial pressure (MAP) leads to this physiological entrainment independently, or if heart rate (HR) and/or the partial pressure of carbon dioxide (Pco2) also have contributing influences. A 2:1 control-to-case model was used in the present investigation [participant number (n) = 40; n = 16 age-matched (AM); n = 16 donor control (DM); n = 8 heart transplant recipients (HTRs)]. The latter group was used to mechanistically isolate the extent to which HR influences the cerebral pressure-flow relationship. Participants completed 5 min of squat-stand maneuvers at 0.05 Hz (10 s) and 0.10 Hz (5 s). Linear transfer function analysis (TFA) examined the relationship between different physiological inputs (i.e., MAP, HR, and Pco2) and output [cerebral blood velocity (CBV)] during SSM; and cardiac baroreceptor sensitivity (BRS). Compared with DM, cardiac BRS was reduced in AM (P < 0.001), which was further reduced in HTR (P < 0.045). In addition, during the SSM, HR was elevated in HTR compared with both control groups (P < 0.001), but all groups had near-maximal coherence metrics ≥0.98 at 0.05 Hz and ≥0.99 at 0.10 Hz (P ≥ 0.399). In contrast, the mean HR-CBV/Pco2-CBV relationships ranged from 0.38 (HTR) to 0.81 (DM). Despite near abolishment of BRS and blunted HR following heart transplantation, long-term HTR exhibited near-maximal coherence within the MAP-CBV relationship, comparable with AM and DM. Therefore, these results show that the augmented coherence with SSM is driven by blood pressure, whereas elevations in TFA coherence as a result of HR contribution are likely correlational in nature.


Assuntos
Pressão Arterial , Circulação Cerebrovascular , Exercício Físico , Frequência Cardíaca , Transplante de Coração , Contração Muscular , Sobreviventes , Transplantados , Adulto , Idoso , Barorreflexo , Estudos de Casos e Controles , Homeostase , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
7.
Neurobiol Learn Mem ; 183: 107464, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34015438

RESUMO

OBJECTIVES: The goal of the present study was to identify the role of the medial temporal lobe (MTL) in the detection and later processing of novelty. METHODS: Twenty-one epilepsy patients with unilateral MTL resection (10 left-sided; 11 right-sided) and 26 matched healthy controls performed an adapted visual novelty oddball task. In this task two streams of stimuli were presented on the left and right of fixation while the patients' electroencephalogram was measured. The participants had to respond to infrequent target stimuli, while ignoring frequent standard, and infrequent novel stimuli that were presented to the left or right, appearing either contra- or ipsilateral to the patients' resections. RESULTS: Novelty detection, as indexed by the N2 ERP component elicited by novels, was reduced by the MTL resections, as evidenced by a smaller N2 for patients than healthy controls. Later processing of novels, as indexed by the novelty P3 ERP component, was reduced for novels presented contra- versus ipsilateral to the resected side. Moreover, at a frontal electrode site, the N2-P3 complex showed reduced novelty processing in patients with MTL resections compared to healthy controls. The ERP differences were specific for the novel stimuli, as target processing, as indexed by the P3b, was unaffected in the patients: No P3b differences were found between targets presented ipsi- or contralaterally to the resected side, nor between patients and healthy controls. CONCLUSIONS: The current results suggest that MTL structures play a role in novelty processing. In contrast, target processing was unaffected by MTL resections.


Assuntos
Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia do Lobo Temporal/cirurgia , Potenciais Evocados P300/fisiologia , Comportamento Exploratório/fisiologia , Hipocampo/cirurgia , Lobo Temporal/fisiologia , Adulto , Estudos de Casos e Controles , Epilepsia Resistente a Medicamentos/fisiopatologia , Eletroencefalografia , Potenciais Evocados , Feminino , Hipocampo/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Psicológico , Lobo Temporal/cirurgia , Adulto Jovem
8.
Proc Natl Acad Sci U S A ; 115(12): E2811-E2818, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29507241

RESUMO

The pH (low) insertion peptides (pHLIPs) target acidity at the surfaces of cancer cells and show utility in a wide range of applications, including tumor imaging and intracellular delivery of therapeutic agents. Here we report pHLIP constructs that significantly improve the targeted delivery of agents into tumor cells. The investigated constructs include pHLIP bundles (conjugates consisting of two or four pHLIP peptides linked by polyethylene glycol) and Var3 pHLIPs containing either the nonstandard amino acid, γ-carboxyglutamic acid, or a glycine-leucine-leucine motif. The performance of the constructs in vitro and in vivo was compared with previous pHLIP variants. A wide range of experiments was performed on nine constructs including (i) biophysical measurements using steady-state and kinetic fluorescence, circular dichroism, and oriented circular dichroism to study the pH-dependent insertion of pHLIP variants across the membrane lipid bilayer; (ii) cell viability assays to gauge the pH-dependent potency of peptide-toxin constructs by assessing the intracellular delivery of the polar, cell-impermeable cargo molecule amanitin at physiological and low pH (pH 7.4 and 6.0, respectively); and (iii) tumor targeting and biodistribution measurements using fluorophore-peptide conjugates in a breast cancer mouse model. The main principles of the design of pHLIP variants for a range of medical applications are discussed.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Proteínas de Membrana/química , Peptídeos/administração & dosagem , Amanitinas/química , Animais , Antineoplásicos/química , Dicroísmo Circular , Feminino , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Bicamadas Lipídicas/química , Lipossomos/química , Proteínas de Membrana/genética , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/tratamento farmacológico , Peptídeos/química , Peptídeos/farmacocinética , Polietilenoglicóis/química , Distribuição Tecidual
9.
Planta ; 251(2): 45, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31915930

RESUMO

MAIN CONCLUSION: Adaptation of the xylem under dehydration to smaller sized vessels and the increase in xylem density per stem area facilitate water transport during water-limiting conditions, and this has implications for assimilate transport during drought. The potato stem is the communication and transport channel between the assimilate-exporting source leaves and the terminal sink tissues of the plant. During environmental stress conditions like water scarcity, which adversely affect the performance (canopy growth and tuber yield) of the potato plant, the response of stem tissues is essential, however, still understudied. In this study, we investigated the response of the stem tissues of cultivated potato grown in the greenhouse to dehydration using a multidisciplinary approach including physiological, biochemical, morphological, microscopic, and magnetic resonance imaging techniques. We observed the most significant effects of water limitation in the lower stem regions of plants. The light microscopy analysis of the potato stem sections revealed that plants exposed to this particular dehydration stress have higher total xylem density per unit area than control plants. This increase in the total xylem density was accompanied by an increase in the number of narrow-diameter xylem vessels and a decrease in the number of large-diameter xylem vessels. Our MRI approach revealed a diurnal rhythm of xylem flux between day and night, with a reduction in xylem flux that is linked to dehydration sensitivity. We also observed that sink strength was the main driver of assimilate transport through the stem in our data set. These findings may present potential breeding targets for drought tolerance in potato.


Assuntos
Solanum tuberosum/metabolismo , Solanum tuberosum/fisiologia , Xilema/metabolismo , Xilema/fisiologia , Adaptação Fisiológica/fisiologia , Transporte Biológico/fisiologia , Secas , Imageamento por Ressonância Magnética , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Transpiração Vegetal/fisiologia
10.
J Exp Bot ; 70(9): 2575-2586, 2019 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-30882149

RESUMO

We explored the use of the eco-physiological crop model GECROS to identify markers for improved rice yield under well-watered (control) and water deficit conditions. Eight model parameters were measured from the control in one season for 267 indica genotypes. The model accounted for 58% of yield variation among genotypes under control and 40% under water deficit conditions. Using 213 randomly selected genotypes as the training set, 90 single nucleotide polymorphism (SNP) loci were identified using a genome-wide association study (GWAS), explaining 42-77% of crop model parameter variation. SNP-based parameter values estimated from the additive loci effects were fed into the model. For the training set, the SNP-based model accounted for 37% (control) and 29% (water deficit) of yield variation, less than the 78% explained by a statistical genomic prediction (GP) model for the control treatment. Both models failed in predicting yields of the 54 testing genotypes. However, compared with the GP model, the SNP-based crop model was advantageous when simulating yields under either control or water stress conditions in an independent season. Crop model sensitivity analysis ranked the SNP loci for their relative importance in accounting for yield variation, and the rank differed greatly between control and water deficit environments. Crop models have the potential to use single-environment information for predicting phenotypes under different environments.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Oryza/genética , Estudos de Associação Genética
11.
BMC Plant Biol ; 16(1): 187, 2016 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-27576474

RESUMO

BACKGROUND: Within onion, Allium cepa L., the availability of disease resistance is limited. The identification of sources of resistance in related species, such as Allium roylei and Allium fistulosum, was a first step towards the improvement of onion cultivars by breeding. SNP markers linked to resistance and polymorphic between these related species and onion cultivars are a valuable tool to efficiently introgress disease resistance genes. In this paper we describe the identification and validation of SNP markers valuable for onion breeding. RESULTS: Transcriptome sequencing resulted in 192 million RNA seq reads from the interspecific F1 hybrid between A. roylei and A. fistulosum (RF) and nine onion cultivars. After assembly, reliable SNPs were discovered in about 36 % of the contigs. For genotyping of the interspecific three-way cross population, derived from a cross between an onion cultivar and the RF (CCxRF), 1100 SNPs that are polymorphic in RF and monomorphic in the onion cultivars (RF SNPs) were selected for the development of KASP assays. A molecular linkage map based on 667 RF-SNP markers was constructed for CCxRF. In addition, KASP assays were developed for 1600 onion-SNPs (SNPs polymorphic among onion cultivars). A second linkage map was constructed for an F2 of onion x A. roylei (F2(CxR)) that consisted of 182 onion-SNPs and 119 RF-SNPs, and 76 previously mapped markers. Markers co-segregating in both the F2(CxR) and the CCxRF population were used to assign the linkage groups of RF to onion chromosomes. To validate usefulness of these SNP markers, QTL mapping was applied in the CCxRF population that segregates for resistance to Botrytis squamosa and resulted in a QTL for resistance on chromosome 6 of A. roylei. CONCLUSIONS: Our research has more than doubled the publicly available marker sequences of expressed onion genes and two onion-related species. It resulted in a detailed genetic map for the interspecific CCxRF population. This is the first paper that reports the detection of a QTL for resistance to B. squamosa in A. roylei.


Assuntos
Cebolas/genética , Polimorfismo de Nucleotídeo Único , Allium/genética , Allium/fisiologia , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Genótipo , Hibridização Genética , Cebolas/fisiologia
12.
Bioconjug Chem ; 27(9): 2014-23, 2016 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-27396694

RESUMO

pH (low) insertion peptides (pHLIP peptides) target acidic extracellular environments in vivo due to pH-dependent cellular membrane insertion. Two variants (Var3 and Var7) and wild-type (WT) pHLIP peptides have shown promise for in vivo imaging of breast cancer. Two positron emitting radionuclides ((64)Cu and (18)F) were used to label the NOTA- and NO2A-derivatized Var3, Var7, and WT peptides for in vivo biodistribution studies in 4T1 orthotopic tumor-bearing BALB/c mice. All of the constructs were radiolabeled with (64)Cu or [(18)F]-AlF in good yield. The in vivo biodistribution of the 12 constructs in 4T1 orthotopic allografted female BALB/c mice indicated that NO2A-cysVar3, radiolabeled with either (18)F (4T1 uptake; 8.9 ± 1.7%ID/g at 4 h p.i.) or (64)Cu (4T1 uptake; 8.2 ± 0.9%ID/g at 4 h p.i. and 19.2 ± 1.8% ID/g at 24 h p.i.), shows the most promise for clinical translation. Additional studies to investigate other tumor models (melanoma, prostate, and brain tumor models) indicated the universality of tumor targeting of these tracers. From this study, future clinical translation will focus on (18)F- or (64)Cu-labeled NO2A-cysVar3.


Assuntos
Radioisótopos de Cobre , Espaço Extracelular/química , Radioisótopos de Flúor , Proteínas de Membrana , Tomografia por Emissão de Pósitrons/métodos , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Proteínas de Membrana/química , Proteínas de Membrana/farmacocinética , Camundongos , Camundongos Endogâmicos BALB C , Traçadores Radioativos , Relação Estrutura-Atividade , Distribuição Tecidual
13.
Plant Cell Environ ; 39(9): 1895-908, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27353051

RESUMO

In plants, tolerance to drought stress is a result of numerous minor effect loci in which transcriptional regulation contributes significantly to the observed phenotypes. Under severe drought conditions, a major expression quantitative trait loci hotspot was identified on chromosome five in potato. A putative Nuclear factor y subunit C4 was identified as key candidate in the regulatory cascade in response to drought. Further investigation of the eQTL hotspots suggests a role for a putative Homeobox leucine zipper protein 12 in relation to drought in potato. Genes strongly co-expressed with Homeobox leucine zipper protein 12 were plant growth regulators responsive to water deficit stress in Arabidopsis thaliana, implying a possible conserved mechanism. Integrative analysis of genetic, genomic, phenotypic and transcriptomic data provided insights in the downstream functional components of the drought response. The abscisic acid- and environmental stress-inducible protein TAS14 was highly induced by severe drought in potato and acts as a reliable biomarker for the level of stress perceived by the plant. The systems genetics approach supported a role for multiple genes responsive to severe drought stress of Solanum tuberosum. The combination of gene regulatory networks, expression quantitative trait loci mapping and phenotypic analysis proved useful for candidate gene selection.


Assuntos
Adaptação Biológica , Secas , Regulação da Expressão Gênica de Plantas , Genes Reguladores , Solanum tuberosum/genética , Diploide , Redes Reguladoras de Genes , Genômica , Proteínas de Plantas/genética , Locos de Características Quantitativas , Biologia de Sistemas
14.
J Exp Bot ; 67(17): 5119-32, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27436279

RESUMO

Stress conditions in agricultural ecosystems can occur at variable intensities. Different resistance mechanisms against abiotic stress and pathogens are deployed by plants. Thus, it is important to examine plant responses to stress combinations under different scenarios. Here, we evaluated the effect of different levels of salt stress ranging from mild to severe (50, 100, and 150mM NaCl) on powdery mildew resistance and overall performance of tomato introgression lines with contrasting levels of partial resistance, as well as near-isogenic lines (NILs) carrying the resistance gene Ol-1 (associated with a slow hypersensitivity response; HR), ol-2 (an mlo mutant associated with papilla formation), and Ol-4 (an R gene associated with a fast HR). Powdery mildew resistance was affected by salt stress in a genotype- and stress intensity-dependent manner. In susceptible and partial resistant lines, increased susceptibility was observed under mild salt stress (50mM) which was accompanied by accelerated cell death-like senescence. In contrast, severe salt stress (150mM) reduced disease symptoms. Na(+) and Cl(-) accumulation in the leaves was linearly related to the decreased pathogen symptoms under severe stress. In contrast, complete resistance mediated by ol-2 and Ol-4 was unaffected under all treatment combinations, and was associated with a decreased growth penalty. Increased susceptibility and senescence under combined stress in NIL-Ol-1 was associated with the induction of ethylene and jasmonic acid pathway genes and the cell wall invertase gene LIN6. These results highlight the significance of stress severity and resistance type on the plant's performance under the combination of abiotic and biotic stress.


Assuntos
Resistência à Doença/fisiologia , Tolerância ao Sal/fisiologia , Solanum lycopersicum/fisiologia , Ascomicetos , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Solanum lycopersicum/genética , Solanum lycopersicum/microbiologia , Doenças das Plantas/microbiologia , Tolerância ao Sal/genética , Estresse Fisiológico/fisiologia
15.
Eur J Clin Microbiol Infect Dis ; 34(9): 1901-3, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26194692

RESUMO

Ampicillin-resistant Enterococcus faecium (AREfm) has gained increased footholds in many hospital intensive care units (ICUs) and belongs to specific hospital-adapted E. faecium sub-populations. Three AREfm strains survived in an in vitro survival setting for approximately 5.5 years. These findings have important consequences for the epidemiology of AREfm in hospital settings and stress the importance of maintaining a good level of hospital hygiene.


Assuntos
Ampicilina/farmacologia , Antibacterianos/farmacologia , Enterococcus faecium/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/microbiologia , Vancomicina/farmacologia , Resistência a Ampicilina , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla , Enterococcus faecium/crescimento & desenvolvimento , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/transmissão , Hospitais , Humanos , Testes de Sensibilidade Microbiana
16.
Graefes Arch Clin Exp Ophthalmol ; 253(11): 1979-83, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26267751

RESUMO

PURPOSE: To investigate the effect of aging on ocular parameters, including intraocular pressure (IOP), measured with different tonometry methods in healthy young (HY) and healthy elderly (HE) subjects and to study the effect of corneal parameters on tonometry methods. METHODS: In this prospective, cross-sectional study, fifty eyes of 50 HY subjects (28 females, 22-31 years of age) and 43 eyes of 43 HE subjects (22 females, 64-79) were included. IOP was measured with four tonometry methods in a standardized order: ocular response analyser (ORA), dynamic contour tonometry (DCT), applanation resonance tonometry (ART) and Goldmann applanation tonometry (GAT). Other measurements included axial length (AL), central corneal thickness (CCT), corneal curvature (CC), anterior chamber volume (ACV), corneal hysteresis (CH) and corneal resistance factor (CRF). RESULTS: The mean IOP (HY/HE; mmHg ± standard deviation (SD)) was 12.2 ± 2.2/14.1 ± 3.5 with GAT. IOP was significantly higher (difference ± standard error) in HE compared to HY measured with an ORA (+3.1 mmHg ± 0.6), GAT (+1.9 ± 0.6) and DCT (+1.6 ± 0.6). No significant difference was found in IOP measured with ART. CH and ACV were significantly lower in HE compared to HY. There was no difference between the groups in CCT, CC, AL or CRF. No tonometry method was dependant on CCT or CC. CONCLUSIONS: IOP measured with an ORA and via DCT and GAT was higher in HE compared to HY Swedish subjects, while IOP measured with ART did not differ between the groups. In these homogeneous groups, tonometry methods were independent of CCT and CC.


Assuntos
Envelhecimento/fisiologia , Câmara Anterior/anatomia & histologia , Comprimento Axial do Olho/anatomia & histologia , Córnea/anatomia & histologia , Pressão Intraocular/fisiologia , Adulto , Idoso , Paquimetria Corneana , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tonometria Ocular , Adulto Jovem
17.
J Neurotrauma ; 41(13-14): 1509-1523, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38468559

RESUMO

Sport-related concussion (SRC) can impair the cerebrovasculature both acutely and chronically. Transcranial Doppler (TCD) ultrasound assessment has the potential to illuminate the mechanisms of impairment and provide an objective evaluation of SRC. The current systematic review investigated studies employing TCD ultrasound assessment of intracranial arteries across three broad categories of cerebrovascular regulation: neurovascular coupling (NVC), cerebrovascular reactivity (CVR), and dynamic cerebral autoregulation (dCA). The current review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) database (CRD42021275627). The search strategy was applied to PubMed, as this database indexes all biomedical journals. Original articles on TCD for athletes with medically diagnosed SRC were included. Title/abstract and full-text screening were completed by three authors. Two authors completed data extraction and risk of bias using the Methodological Index for Non-Randomized Studies and Scottish Intercollegiate Guideline Network checklists. Of the 141 articles identified, 14 met the eligibility criteria. One article used an NVC challenge, eight assessed CVR, and six investigated dCA. Methodologies varied widely among studies, and results were heterogeneous. There was evidence of cerebrovascular impairment in all three domains roughly 2 days post-SRC, but the magnitude and recovery of these impairments were not clear. There was evidence that clinical symptom resolution occurred before cerebrovascular function, indicating that physiological deficits may persist despite clinical recovery and return to play. Collectively, this emphasizes an opportunity for the use of TCD to illuminate the cerebrovascular deficits caused by SRC. It also highlights that there is need for consistent methodological rigor when employing TCD in a SRC population.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Ultrassonografia Doppler Transcraniana , Humanos , Ultrassonografia Doppler Transcraniana/métodos , Concussão Encefálica/diagnóstico por imagem , Concussão Encefálica/fisiopatologia , Traumatismos em Atletas/diagnóstico por imagem , Traumatismos em Atletas/fisiopatologia , Circulação Cerebrovascular/fisiologia , Acoplamento Neurovascular/fisiologia
18.
Pediatr Neurol ; 150: 97-106, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38006666

RESUMO

BACKGROUND: Sport-related concussion (SRC) has been shown to induce cerebral neurophysiological deficits, quantifiable with electroencephalography (EEG). As the adolescent brain is undergoing rapid neurodevelopment, it is fundamental to understand both the short- and long-term ramifications SRC may have on neuronal functioning. The current systematic review sought to amalgamate the literature regarding both acute/subacute (≤28 days) and chronic (>28 days) effects of SRC in adolescents via EEG and the diagnostic accuracy of this tool. METHODS: The review was registered within the Prospero database (CRD42021275256). Search strategies were created and input into the PubMed database, where three authors completed all screening. Risk of bias assessments were completed using the Scottish Intercollegiate Guideline Network and Methodological Index for Non-Randomized Studies. RESULTS: A total of 128 articles were identified; however, only seven satisfied all inclusion criteria. The studies ranged from 2012 to 2021 and included sample sizes of 21 to 81 participants, albeit only ∼14% of the included athletes were females. The studies displayed low-to-high levels of bias due to the small sample sizes and preliminary nature of most investigations. Although heterogeneous methods, tasks, and analytical techniques were used, 86% of the studies found differences compared with control athletes, in both the symptomatic and asymptomatic phases of SRC. One study used raw EEG data as a diagnostic indicator demonstrating promise; however, more research and standardization are a necessity. CONCLUSIONS: Collectively, the findings highlight the utility of EEG in assessing adolescent SRC; however, future studies should consider important covariates including biological sex, maturation status, and development.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Esportes Juvenis , Feminino , Adolescente , Humanos , Masculino , Traumatismos em Atletas/complicações , Traumatismos em Atletas/diagnóstico , Concussão Encefálica/diagnóstico , Concussão Encefálica/etiologia , Encéfalo , Atletas
19.
JAMA Netw Open ; 7(9): e2431959, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39235809

RESUMO

Importance: Blood-based biomarkers may clarify underlying neuropathology and potentially assist in clinical management of adolescents with sport-related concussion (SRC). Objective: To investigate the association between SRC and plasma biomarkers in adolescents. Design, Setting, and Participants: Prospective cohort study in Canadian sport and clinic settings (Surveillance in High Schools and Community Sport to Reduce Concussions and Their Consequences study; September 2019 to November 2022). Participants were a convenience sample of 849 adolescent (ages 10-18 years) sport participants with blood samples. Data were analyzed from February to September 2023. Exposures: Blood collection and clinical testing preseason (uninjured) and post-SRC follow-ups (ie, ≤72 hours, 1 week, and biweekly until medical clearance to return to play [RTP]). Main Outcomes and Measures: Plasma glial fibrillary acidic protein (GFAP), ubiquitin c-terminal hydrolase-L1 (UCH-L1), neurofilament light (NfL), and total tau (t-tau) were assayed. Group-level comparisons of biomarker levels were conducted between uninjured and post-SRC intervals (postinjury day [PID] 0-3, 4-10, 11-28, and >28) considering age and sex as modifiers. Secondary analyses explored associations between biomarker concentrations and clinical outcomes (Sport Concussion Assessment Tool, Fifth Edition [SCAT5] symptom scores and time to RTP). Results: This study included 1023 plasma specimens from 695 uninjured participants (467 male participants [67.2%]; median [IQR] age, 15.90 [15.13-16.84] years) and 154 participants with concussion (78 male participants [51.0%]; median [IQR] age, 16.12 [15.31-17.11] years). Acute (PID 0-3) differences relative to uninjured levels were found for GFAP (female participants: 17.8% increase; ß = 0.164; 95% CI, 0.064 to 0.263; P = .001; male participants: 17.1% increase; ß = 0.157; 95% CI, 0.086 to 0.229; P < .001), UCH-L1 (female participants: 43.4% increase; ß = 0.361; 95% CI, 0.125 to 0.596; P = .003), NfL (male participants: 19.0% increase; ß = 0.174; 95% CI, 0.087 to 0.261; P < .001), and t-tau (female participants: -22.9%; ß = -0.260; 95% CI, -0.391 to -0.130; P < .001; male participants: -18.4%; ß = -0.203; 95% CI, -0.300 to -0.106; P < .001). Differences were observed for all biomarkers at PID 4 to 10, 11 to 28, and greater than 28 compared with uninjured groups. GFAP, NfL, and t-tau were associated with SCAT5 symptom scores across several PID intervals. Higher GFAP after 28 days post-SRC was associated with earlier clearance to RTP (hazard ratio, 4.78; 95% CI, 1.59 to 14.31; P = .01). Male participants exhibited lower GFAP (-9.7%), but higher UCH-L1 (21.3%) compared with female participants. Age was associated with lower GFAP (-5.4% per year) and t-tau (-5.3% per year). Conclusions and Relevance: In this cohort study of 849 adolescents, plasma biomarkers differed between uninjured participants and those with concussions, supporting their continued use to understand concussion neuropathology. Age and sex are critical considerations as these biomarkers progress toward clinical validation.


Assuntos
Traumatismos em Atletas , Biomarcadores , Concussão Encefálica , Proteínas tau , Humanos , Adolescente , Masculino , Feminino , Biomarcadores/sangue , Concussão Encefálica/sangue , Concussão Encefálica/complicações , Estudos Prospectivos , Traumatismos em Atletas/sangue , Traumatismos em Atletas/complicações , Criança , Proteínas tau/sangue , Proteínas de Neurofilamentos/sangue , Ubiquitina Tiolesterase/sangue , Proteína Glial Fibrilar Ácida/sangue , Canadá , Lesões Encefálicas Traumáticas/sangue
20.
Biology (Basel) ; 13(9)2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39336123

RESUMO

Traditional approaches employing natural plant products to treat a wide array of ailments have been documented and described for thousands of years. However, there remains limited scientific study of the therapeutic potential or effectiveness of ethnobotanical applications. Increases in the incidence of cancer and emerging infectious diseases demonstrate a growing need for advances in the development of therapeutic options. In this study, we evaluate the therapeutic potential of aqueous extracts prepared from four plants, purple aster (Symphyotrichum novae-angliae (L.) Nemsom), common sage (Salvia lyrata (L.)), northern spicebush (Lindera benzoin (L.) Blume), and lamb's ear (Stachys byzantina (K.) Koch)) traditionally used in Native American medicine in Indiana, USA. Using a combination of cytotoxicity assays, immunofluorescence microscopy, and antiviral assays, we found that sage and spicebush extracts exhibit cytotoxic and antiproliferative effects on HeLa cell proliferation and that sage, spicebush, and aster extracts were capable of significantly inhibiting human respiratory syncytial virus (hRSV), a major respiratory pathogen of infants and the elderly. Chemical analysis of the four extracts identified four major compounds which were subsequently evaluated to identify the responsible constituents in the extracts. While none of the identified compounds were shown to induce significant impacts on HeLa cell proliferation, two of the compounds, (1S)-(-)-Borneol and 5-(hydroxymethyl)-furfural, identified in sage and spicebush, respectively, were shown to have antiviral activities. Our data suggest that several of the extracts tested exhibited either anti-proliferative or antiviral activity supporting future further analysis.

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