Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 131
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Infect Dis ; 227(10): 1121-1126, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-36478252

RESUMO

The lack of a long-term in vitro culture method has severely restricted the study of Plasmodium vivax, in part because it limits genetic manipulation and reverse genetics. We used the recently optimized Plasmodium cynomolgi Berok in vitro culture model to investigate the putative P. vivax drug resistance marker MDR1 Y976F. Introduction of this mutation using clustered regularly interspaced short palindromic repeats-CRISPR-associated protein 9 (CRISPR-Cas9) increased sensitivity to mefloquine, but had no significant effect on sensitivity to chloroquine, amodiaquine, piperaquine, and artesunate. To our knowledge, this is the first reported use of CRISPR-Cas9 in P. cynomolgi, and the first reported integrative genetic manipulation of this species.


Assuntos
Antimaláricos , Plasmodium cynomolgi , Mefloquina/farmacologia , Antimaláricos/farmacologia , Cloroquina/farmacologia , Plasmodium vivax/genética , Resistência a Medicamentos/genética , Resistência a Múltiplos Medicamentos/genética , Plasmodium falciparum
2.
Antimicrob Agents Chemother ; 67(7): e0173022, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37338381

RESUMO

Ivermectin is an endectocide used widely to treat a variety of internal and external parasites. Field trials of ivermectin mass drug administration for malaria transmission control have demonstrated a reduction of Anopheles mosquito survival and human malaria incidence. Ivermectin will mostly be deployed together with artemisinin-based combination therapies (ACT), the first-line treatment of falciparum malaria. It has not been well established if ivermectin has activity against asexual stage Plasmodium falciparum or if it interacts with the parasiticidal activity of other antimalarial drugs. This study evaluated antimalarial activity of ivermectin and its metabolites in artemisinin-sensitive and artemisinin-resistant P. falciparum isolates and assessed in vitro drug-drug interaction with artemisinins and its partner drugs. The concentration of ivermectin causing half of the maximum inhibitory activity (IC50) on parasite survival was 0.81 µM with no significant difference between artemisinin-sensitive and artemisinin-resistant isolates (P = 0.574). The ivermectin metabolites were 2-fold to 4-fold less active than the ivermectin parent compound (P < 0.001). Potential pharmacodynamic drug-drug interactions of ivermectin with artemisinins, ACT-partner drugs, and atovaquone were studied in vitro using mixture assays providing isobolograms and derived fractional inhibitory concentrations. There were no synergistic or antagonistic pharmacodynamic interactions when combining ivermectin and antimalarial drugs. In conclusion, ivermectin does not have clinically relevant activity against the asexual blood stages of P. falciparum. It also does not affect the in vitro antimalarial activity of artemisinins or ACT-partner drugs against asexual blood stages of P. falciparum.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Malária , Animais , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Plasmodium falciparum , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Malária/tratamento farmacológico , Combinação de Medicamentos , Resistência a Medicamentos
3.
Arch Orthop Trauma Surg ; 143(1): 353-358, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34985565

RESUMO

INTRODUCTION: Elderly patients with concomitant upper limb and hip fractures present a management dilemma because upper limb fractures potentially affect rehabilitation outcomes for the hip fracture. This study aims to evaluate whether the site of upper limb fractures and the decision to surgically treat such fractures affect the functional outcome of surgically treated hip fracture patients. METHODOLOGY: We retrospectively reviewed 1828 hip fracture patients treated at a single trauma centre over 3 years, of whom 42 with surgically treated hip fractures had concomitant upper limb fractures. Outcome measures, such as length of hospital stay, complications, mortality and readmission rates, were assessed, whilst the functional outcomes were evaluated using the Modified Barthel Index (MBI) on admission, post-operatively and at 6 and 12 months of follow-up. RESULTS: Amongst the 42 patients with surgically treated hip fractures, 31.0% had proximal humerus fractures, 50.0% had wrist fractures, 16.7% had elbow fractures and 2.4% had forearm fractures. 50.0% of these upper limb fractures were treated surgically. There was no difference in complications, inpatient morbidity, readmission rates or the length of hospital stay for patients whose upper limb fractures were surgically treated as compared to those non-surgically treated. There was no difference in absolute MBI scores at 6 and 12 months based on the management of upper limb fractures. However, patients with surgically treated wrist fractures had statistically significant higher MBI scores at 6 months as compared to those treated non-surgically. CONCLUSION: Surgical treatment of concomitant upper limb fractures does not appear to change the outcomes of the hip fractures. Hip fracture patients with surgically treated wrist fractures had better functional outcomes at 6 months compared to those treated non-surgically; however, there was no difference at 12 months. Hip fracture patients with concomitant wrist fractures had better functional outcomes compared to hip fracture patients with proximal humerus fractures.


Assuntos
Traumatismos do Braço , Fraturas do Quadril , Fraturas do Úmero , Fraturas do Ombro , Traumatismos do Punho , Humanos , Idoso , Estudos Retrospectivos , Fraturas do Quadril/complicações , Fraturas do Quadril/cirurgia , Fraturas do Quadril/epidemiologia , Resultado do Tratamento , Traumatismos do Punho/complicações , Extremidade Superior , Fraturas do Úmero/complicações
4.
Pract Neurol ; 23(3): 229-238, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36882323

RESUMO

Shoulder pain is common after neurological injury and can be disabling, lead to poor functional outcomes and increase care costs. Its cause is multifactoral and several pathologies contribute to the presentation. Astute diagnostic skills and a multidisciplinary approach are required to recognise what is clinically relevant and to implement appropriate stepwise management. In the absence of large clinical trial data, we aim to provide a comprehensive, practical and pragmatic overview of shoulder pain in patients with neurological conditions. We use available evidence to produce a management guideline, taking into account specialty opinions from neurology, rehabilitation medicine, orthopaedics and physiotherapy.


Assuntos
Dor de Ombro , Acidente Vascular Cerebral , Humanos , Hemiplegia/etiologia , Hemiplegia/reabilitação , Manejo da Dor , Dor de Ombro/diagnóstico , Dor de Ombro/etiologia , Dor de Ombro/terapia , Acidente Vascular Cerebral/complicações
5.
BMC Genomics ; 23(1): 780, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36451097

RESUMO

BACKGROUND: Important regulation occurs at the level of transcription in Plasmodium falciparum and growing evidence suggests that these apicomplexan parasites have complex regulatory networks. Recent studies implicate long noncoding RNAs (lncRNAs) as transcriptional regulators in P. falciparum. However, due to limited research and the lack of necessary experimental tools, our understanding of their role in the malaria-causing parasite remains largely unelucidated. In this work, we address one of these limitations, the lack of an updated and improved lncRNA annotation in P. falciparum. RESULTS: We generated long-read RNA sequencing data and integrated information extracted and curated from multiple sources to manually annotate lncRNAs. We identified 1119 novel lncRNAs and validated and refined 1250 existing annotations. Utilising the collated datasets, we generated evidence-based ranking scores for each annotation and characterised the distinct genomic contexts and features of P. falciparum lncRNAs. Certain features indicated subsets with potential biological significance such as 25 lncRNAs containing multiple introns, 335 lncRNAs lacking mutations in piggyBac mutagenic studies and lncRNAs associated with specific biologic processes including two new types of lncRNAs found proximal to var genes. CONCLUSIONS: The insights and the annotation presented in this study will serve as valuable tools for researchers seeking to understand the role of lncRNAs in parasite biology through both bioinformatics and experimental approaches.


Assuntos
Malária Falciparum , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Genômica , Malária Falciparum/genética , Plasmodium falciparum/genética , Biologia Computacional
6.
PLoS Pathog ; 16(4): e1008482, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32310999

RESUMO

The emergence of artemisinin (ART) resistance in Plasmodium falciparum intra-erythrocytic parasites has led to increasing treatment failure rates with first-line ART-based combination therapies in Southeast Asia. Decreased parasite susceptibility is caused by K13 mutations, which are associated clinically with delayed parasite clearance in patients and in vitro with an enhanced ability of ring-stage parasites to survive brief exposure to the active ART metabolite dihydroartemisinin. Herein, we describe a panel of K13-specific monoclonal antibodies and gene-edited parasite lines co-expressing epitope-tagged versions of K13 in trans. By applying an analytical quantitative imaging pipeline, we localize K13 to the parasite endoplasmic reticulum, Rab-positive vesicles, and sites adjacent to cytostomes. These latter structures form at the parasite plasma membrane and traffic hemoglobin to the digestive vacuole wherein artemisinin-activating heme moieties are released. We also provide evidence of K13 partially localizing near the parasite mitochondria upon treatment with dihydroartemisinin. Immunoprecipitation data generated with K13-specific monoclonal antibodies identify multiple putative K13-associated proteins, including endoplasmic reticulum-resident molecules, mitochondrial proteins, and Rab GTPases, in both K13 mutant and wild-type isogenic lines. We also find that mutant K13-mediated resistance is reversed upon co-expression of wild-type or mutant K13. These data help define the biological properties of K13 and its role in mediating P. falciparum resistance to ART treatment.


Assuntos
Resistência a Medicamentos/genética , Plasmodium falciparum/genética , Antimaláricos/farmacologia , Artemisininas/farmacologia , Resistência a Medicamentos/fisiologia , Humanos , Malária Falciparum/parasitologia , Mutação , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo
7.
Nutr Neurosci ; 25(8): 1697-1703, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33666531

RESUMO

BACKGROUND: Persons with autism spectrum disorder (ASD) can have restrictive diets due to stereotyped behaviors. These restrictive diets can manifest with nutritional deficiencies, such as Vitamin A deficiency. The most frequent manifestation of hypovitaminosis A is vision loss secondary to xerophthalmia. Here the authors report six cases of males with a clinical triad of hypovitaminosis A, cranial hyperostosis, and optic neuropathy. METHODS: A retrospective case series of six males (ages 5-17 years old) with ASD who presented with several weeks of vision loss and nyctalopia were reviewed. RESULTS: All six subjects were found to have a barely detectable Vitamin A level (<10 mcg/dL). Three of the six cases had elevated protein (45.9-74.0 mg/dL) in their CSF. MRI imaging demonstrated mild T2 enhancement of bilateral optic nerve sheaths and CT showed diffuse skull hypertrophy. Upon further history collection, all subjects had a very limited food repertoire with major nutritional deficiencies. Subjects were prescribed high doses of vitamin A and most were noted to have improved vision at follow-up, and all had resolution of imaging abnormalities on repeat scans. No common genetic variant was identified in patients with expanded genetic sequencing. CONCLUSIONS: We present a clinical triad of hypovitaminosis A, cranial hyperostosis, and optic neuropathy in six males with ASD. Skull abnormalities and xeropthalmia likely contributed to the development of vision loss.


Assuntos
Transtorno do Espectro Autista , Hiperostose , Doenças do Nervo Óptico , Deficiência de Vitamina A , Adolescente , Transtorno do Espectro Autista/complicações , Criança , Pré-Escolar , Humanos , Masculino , Nervo Óptico/diagnóstico por imagem , Doenças do Nervo Óptico/etiologia , Estudos Retrospectivos , Vitamina A/uso terapêutico , Deficiência de Vitamina A/complicações
8.
J Sports Sci ; 40(23): 2608-2638, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36862831

RESUMO

This review evaluated the effect of CWI on the temporal recovery profile of physical performance, accounting for environmental conditions and prior exercise modality. Sixty-eight studies met the inclusion criteria. Standardised mean differences were calculated for parameters assessed at <1, 1-6, 24, 48, 72 and ≥96 h post-immersion. CWI improved short-term recovery of endurance performance (p = 0.01, 1 h), but impaired sprint (p = 0.03, 1 h) and jump performance (p = 0.04, 6h). CWI improved longer-term recovery of jump performance (p < 0.01-0.02, 24 h and 96 h) and strength (p < 0.01, 24 h), which coincided with decreased creatine kinase (p < 0.01-0.04, 24-72 h), improved muscle soreness (p < 0.01-0.02, 1-72 h) and perceived recovery (p < 0.01, 72 h). CWI improved the recovery of endurance performance following exercise in warm (p < 0.01) and but not in temperate conditions (p = 0.06). CWI improved strength recovery following endurance exercise performed at cool-to-temperate conditions (p = 0.04) and enhanced recovery of sprint performance following resistance exercise (p = 0.04). CWI seems to benefit the acute recovery of endurance performance, and longer-term recovery of muscle strength and power, coinciding with changes in muscle damage markers. This, however, depends on the nature of the preceding exercise.


Assuntos
Imersão , Músculo Esquelético , Humanos , Músculo Esquelético/fisiologia , Exercício Físico/fisiologia , Mialgia , Água , Desempenho Físico Funcional , Temperatura Baixa
9.
Biol Sport ; 39(3): 529-535, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35959342

RESUMO

This study profiled the changes in running performances and collisions within a Rugby sevens tournament. Sixteen male players were equipped with global positioning system units while competing at the 2015 and 2016 Asia Rugby Sevens series held in Colombo and Hong Kong, respectively. Both tournaments consisted of 4 matches each, and were played over 2 days (i.e., 2 matches/day). Total distance (TD) covered increased in match 3 compared with matches 1 (19 ± 19%; p < 0.001) and 2 (16 ± 11%; p = 0.001), whilst a decrease in TD in match 4 compared with match 3 (8 ± 9%; p = 0.019) was observed. Distances covered within 6.1-12 km·h-1 and 12.1-14 km·h-1 speed bands were generally higher in matches 3 and/or 4 when compared with match 1 and/or 2 (p < 0.05). Frequency of entries into 14.1-18 km·h-1 speed zone was decreased in match 4 compared with match 3 (45 ± 41%; p = 0.009), whilst incidences of heavy, very heavy and severe collisions were generally higher in matches 3 or 4 compared with matches 1 or 2 (p < 0.05). In conclusion, while some decrements in the final match were evident, running performance were generally maintained throughout despite the competitive and congested nature of Rugby Sevens tournaments.

10.
PLoS Pathog ; 15(10): e1008086, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31658303

RESUMO

Plasmodium parasites are the causative agents of malaria, a disease with wide public health repercussions. Increasing drug resistance and the absence of a vaccine make finding new chemotherapeutic strategies imperative. Components of the ubiquitin and ubiquitin-like pathways have garnered increased attention as novel targets given their necessity to parasite survival. Understanding how these pathways are regulated in Plasmodium and identifying differences to the host is paramount to selectively interfering with parasites. Here, we focus on Nedd8 modification in Plasmodium falciparum, given its central role to cell division and DNA repair, processes critical to Plasmodium parasites given their unusual cell cycle and requirement for refined repair mechanisms. By applying a functional chemical approach, we show that deNeddylation is controlled by a different set of enzymes in the parasite versus the human host. We elucidate the molecular determinants of the unusual dual ubiquitin/Nedd8 recognition by the essential PfUCH37 enzyme and, through parasite transgenics and drug assays, determine that only its ubiquitin activity is critical to parasite survival. Our experiments reveal interesting evolutionary differences in how neddylation is controlled in higher versus lower eukaryotes, and highlight the Nedd8 pathway as worthy of further exploration for therapeutic targeting in antimalarial drug design.


Assuntos
Proteína NEDD8/metabolismo , Plasmodium falciparum/metabolismo , Ubiquitina Tiolesterase/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Sequência de Aminoácidos , Antimaláricos/farmacologia , Linhagem Celular , Células HEK293 , Humanos , Hidrólise , Malária Falciparum/tratamento farmacológico , Malária Falciparum/patologia , Ubiquitinação/fisiologia
11.
J Evol Biol ; 34(10): 1554-1567, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34464014

RESUMO

Predation risk is often invoked to explain variation in stress responses. Yet, the answers to several key questions remain elusive, including the following: (1) how predation risk influences the evolution of stress phenotypes, (2) the relative importance of environmental versus genetic factors in stress reactivity and (3) sexual dimorphism in stress physiology. To address these questions, we explored variation in stress reactivity (ventilation frequency) in a post-Pleistocene radiation of live-bearing fish, where Bahamas mosquitofish (Gambusia hubbsi) inhabit isolated blue holes that differ in predation risk. Individuals of populations coexisting with predators exhibited similar, relatively low stress reactivity as compared to low-predation populations. We suggest that this dampened stress reactivity has evolved to reduce energy expenditure in environments with frequent and intense stressors, such as piscivorous fish. Importantly, the magnitude of stress responses exhibited by fish from high-predation sites in the wild changed very little after two generations of laboratory rearing in the absence of predators. By comparison, low-predation populations exhibited greater among-population variation and larger changes subsequent to laboratory rearing. These low-predation populations appear to have evolved more dampened stress responses in blue holes with lower food availability. Moreover, females showed a lower ventilation frequency, and this sexual dimorphism was stronger in high-predation populations. This may reflect a greater premium placed on energy efficiency in live-bearing females, especially under high-predation risk where females show higher fecundities. Altogether, by demonstrating parallel adaptive divergence in stress reactivity, we highlight how energetic trade-offs may mould the evolution of the vertebrate stress response under varying predation risk and resource availability.


Assuntos
Ciprinodontiformes , Comportamento Predatório , Animais , Feminino , Humanos , Fenótipo , Caracteres Sexuais
12.
Biotechnol Bioeng ; 118(8): 3150-3163, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34037982

RESUMO

Bioprinting three-dimensional (3D) tissue equivalents have progressed tremendously over the last decade. 3D bioprinting is currently being employed to develop larger and more physiologic tissues, and it is of particular interest to generate vasculature in biofabricated tissues to aid better perfusion and transport of nutrition. Having an advantage over manual culture systems by bringing together biological scaffold materials and cells in precise 3D spatial orientation, bioprinting could assist in placing endothelial cells in specific spatial locations within a 3D matrix to promote vessel formation at these predefined areas. Hence, in the present study, we investigated the use of bioprinting to generate tissue-level capillary-like networks in biofabricated tissue constructs. First, we developed a bioink using collagen type-1 supplemented with xanthan gum (XG) as a thickening agent. Using a commercial extrusion-based multi-head bioprinter and collagen-XG bioink, the component cells were spatially assembled, wherein the endothelial cells were bioprinted in a lattice pattern and sandwiched between bioprinted fibroblasts layers. 3D bioprinted constructs thus generated were stable, and maintained structural shape and form. Post-print culture of the bioprinted tissues resulted in endothelial sprouting and formation of interconnected capillary-like networks within the lattice pattern and between the fibroblast layers. Bioprinter-assisted spatial placement of endothelial cells resulted in fabrication of patterned prevascularized constructs that enable potential regenerative applications in the future.


Assuntos
Bioimpressão , Colágeno/química , Células Endoteliais/metabolismo , Neovascularização Fisiológica , Impressão Tridimensional , Alicerces Teciduais/química , Linhagem Celular Transformada , Humanos
13.
Biol Lett ; 17(8): 20210261, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34343437

RESUMO

Solar ultraviolet radiation (UVR) is an important environmental threat for organisms in aquatic systems, but its temporally variable nature makes the understanding of its effects ambiguous. The aim of our study was to assess potential fitness costs associated with fluctuating UVR in the aquatic zooplankter Daphnia magna. We investigated individual survival, reproduction and behaviour when exposed to different UVR treatments. Individuals exposed to fluctuating UVR, resembling natural variations in cloud cover, had the lowest fitness (measured as the number of offspring produced during their lifespan). By contrast, individuals exposed to the same, but constant UVR dose had similar fitness to control individuals (not exposed to UVR), but they showed a significant reduction in daily movement. The re-occurring threat response to the fluctuating UVR treatment thus had strong fitness costs for D. magna, and we found no evidence for plastic behavioural responses when continually being exposed to UVR, despite the regular, predictable exposure schedule. In a broader context, our results imply that depending on how variable a stressor is in nature, populations may respond with alternative strategies, a framework that could promote rapid population differentiation and local adaptation.


Assuntos
Daphnia , Raios Ultravioleta , Animais , Humanos , Reprodução
14.
Nature ; 522(7556): 315-20, 2015 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-26085270

RESUMO

There is an urgent need for new drugs to treat malaria, with broad therapeutic potential and novel modes of action, to widen the scope of treatment and to overcome emerging drug resistance. Here we describe the discovery of DDD107498, a compound with a potent and novel spectrum of antimalarial activity against multiple life-cycle stages of the Plasmodium parasite, with good pharmacokinetic properties and an acceptable safety profile. DDD107498 demonstrates potential to address a variety of clinical needs, including single-dose treatment, transmission blocking and chemoprotection. DDD107498 was developed from a screening programme against blood-stage malaria parasites; its molecular target has been identified as translation elongation factor 2 (eEF2), which is responsible for the GTP-dependent translocation of the ribosome along messenger RNA, and is essential for protein synthesis. This discovery of eEF2 as a viable antimalarial drug target opens up new possibilities for drug discovery.


Assuntos
Antimaláricos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Malária/parasitologia , Plasmodium/efeitos dos fármacos , Plasmodium/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Quinolinas/farmacologia , Animais , Antimaláricos/administração & dosagem , Antimaláricos/efeitos adversos , Antimaláricos/farmacocinética , Descoberta de Drogas , Feminino , Estágios do Ciclo de Vida/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/parasitologia , Malária/tratamento farmacológico , Masculino , Modelos Moleculares , Fator 2 de Elongação de Peptídeos/antagonistas & inibidores , Fator 2 de Elongação de Peptídeos/metabolismo , Plasmodium/genética , Plasmodium/crescimento & desenvolvimento , Plasmodium berghei/efeitos dos fármacos , Plasmodium berghei/fisiologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/metabolismo , Plasmodium vivax/efeitos dos fármacos , Plasmodium vivax/metabolismo , Quinolinas/administração & dosagem , Quinolinas/química , Quinolinas/farmacocinética
15.
J Strength Cond Res ; 35(2): 512-518, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29952873

RESUMO

ABSTRACT: Ihsan, M, Yeo, V, Tan, F, Joseph, R, Lee, M, and Aziz, AR. Running demands and activity profile of the new four-quarter match format in men's field hockey. J Strength Cond Res 35(2): 512-518, 2021-This study determined the running demands of men's field hockey with regards to the revised four-quarter match format. Twenty-eight male field hockey players were equipped with global positioning system units while competing in 14 competitive international games over a 1-year period. All matches allowed for unlimited substitutions, and consisted of four 15-minute quarters (i.e., Q1-Q4). A progressive decline in total distance (TD) was observed in Q2 (2,072 ± 141 m) to Q4 (2,055 ± 212 m) compared with Q1 (2,171 ± 195 m, p < 0.05). However, the decline in TD was due to decreases in low-intensity activity (<15 km·h-1, p < 0.05), as high-intensity running (HIR; >15 km·h-1) distances were similar throughout Q1-Q4 (p = 0.263). Positional data demonstrated a similar profile, where significant decreases in TD, but not in HIR, was observed across all playing positions at some point over the 4 quarters (p < 0.05). DEF accumulated the lowest amount of TD (7,631 ± 753 m), HIR (2,257 ± 498 m), and high-intensity decelerations (60 ± 9, >-2m·s-2) compared with MID and FWD (p < 0.05). By contrast, FWD performed the highest amount of HIR (3,090 ± 565 m) and high-intensity accelerations (110 ± 9, >2 m·s-2) compared with MID and DEF (p < 0.05). In conclusion, our results showed that although there was a progressive decline in TD over the 4 quarters of match play, high-intensity running performance (i.e., HIR and high-intensity acceleration) was maintained throughout the match regardless of playing position.


Assuntos
Desempenho Atlético , Hóquei , Aceleração , Sistemas de Informação Geográfica , Humanos , Luz , Masculino
16.
J Sport Exerc Psychol ; 42(4): 307-313, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32702661

RESUMO

In adults, longer quiet-eye (QE) durations have been associated with more successful sport performances and less deterioration in skill during anxiety-inducing situations. This study aimed to establish if QE patterns in youth are similar to those reported in adults. Ten youth shooters, age 13.13 ± 0.83 years, completed an air-pistol task under a control and an anxiety condition. Mixed-design 2 (performance outcome) × 2 (condition) ANOVA tests were conducted with two performance measures-objective and coach rated. No significant main or interaction effects were found. Unlike in adults, performance and anxiety did not differentiate QE duration in youth athletes, although QE duration was longer during good shots than poor shots across both performance measures, and the shortest durations were recorded during poor shots in the anxiety condition. This preliminary exploration encourages more research with youth athletes to determine the efficacy of QE patterns across different learners.

17.
Hum Mutat ; 40(12): 2270-2285, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31206972

RESUMO

Pathogenic variants in the X-linked gene ZC4H2, which encodes a zinc-finger protein, cause an infrequently described syndromic form of arthrogryposis multiplex congenita (AMC) with central and peripheral nervous system involvement. We present genetic and detailed phenotypic information on 23 newly identified families and simplex cases that include 19 affected females from 18 families and 14 affected males from nine families. Of note, the 15 females with deleterious de novo ZC4H2 variants presented with phenotypes ranging from mild to severe, and their clinical features overlapped with those seen in affected males. By contrast, of the nine carrier females with inherited ZC4H2 missense variants that were deleterious in affected male relatives, four were symptomatic. We also compared clinical phenotypes with previously published cases of both sexes and provide an overview on 48 males and 57 females from 42 families. The spectrum of ZC4H2 defects comprises novel and recurrent mostly inherited missense variants in affected males, and de novo splicing, frameshift, nonsense, and partial ZC4H2 deletions in affected females. Pathogenicity of two newly identified missense variants was further supported by studies in zebrafish. We propose ZC4H2 as a good candidate for early genetic testing of males and females with a clinical suspicion of fetal hypo-/akinesia and/or (neurogenic) AMC.


Assuntos
Artrogripose/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mutação , Proteínas Nucleares/genética , Animais , Códon sem Sentido , Modelos Animais de Doenças , Feminino , Mutação da Fase de Leitura , Genes Ligados ao Cromossomo X , Predisposição Genética para Doença , Humanos , Masculino , Mutação de Sentido Incorreto , Linhagem , Fenótipo , Deleção de Sequência , Caracteres Sexuais , Peixe-Zebra
18.
Nature ; 504(7479): 248-253, 2013 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-24284631

RESUMO

Achieving the goal of malaria elimination will depend on targeting Plasmodium pathways essential across all life stages. Here we identify a lipid kinase, phosphatidylinositol-4-OH kinase (PI(4)K), as the target of imidazopyrazines, a new antimalarial compound class that inhibits the intracellular development of multiple Plasmodium species at each stage of infection in the vertebrate host. Imidazopyrazines demonstrate potent preventive, therapeutic, and transmission-blocking activity in rodent malaria models, are active against blood-stage field isolates of the major human pathogens P. falciparum and P. vivax, and inhibit liver-stage hypnozoites in the simian parasite P. cynomolgi. We show that imidazopyrazines exert their effect through inhibitory interaction with the ATP-binding pocket of PI(4)K, altering the intracellular distribution of phosphatidylinositol-4-phosphate. Collectively, our data define PI(4)K as a key Plasmodium vulnerability, opening up new avenues of target-based discovery to identify drugs with an ideal activity profile for the prevention, treatment and elimination of malaria.


Assuntos
1-Fosfatidilinositol 4-Quinase/antagonistas & inibidores , Malária/tratamento farmacológico , Malária/parasitologia , Plasmodium/efeitos dos fármacos , Plasmodium/enzimologia , 1-Fosfatidilinositol 4-Quinase/química , 1-Fosfatidilinositol 4-Quinase/genética , 1-Fosfatidilinositol 4-Quinase/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Sítios de Ligação , Citocinese/efeitos dos fármacos , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/genética , Ácidos Graxos/metabolismo , Feminino , Hepatócitos/parasitologia , Humanos , Imidazóis/metabolismo , Imidazóis/farmacologia , Estágios do Ciclo de Vida/efeitos dos fármacos , Macaca mulatta , Masculino , Modelos Biológicos , Modelos Moleculares , Fosfatos de Fosfatidilinositol/metabolismo , Plasmodium/classificação , Plasmodium/crescimento & desenvolvimento , Pirazóis/metabolismo , Pirazóis/farmacologia , Quinoxalinas/metabolismo , Quinoxalinas/farmacologia , Reprodutibilidade dos Testes , Esquizontes/citologia , Esquizontes/efeitos dos fármacos , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
19.
Intern Med J ; 49(6): 761-769, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30324703

RESUMO

BACKGROUND: Cardiac dysfunction is common in exacerbations of chronic obstructive pulmonary disease (COPD), even in patients without clinically suspected cardiac disorders. AIM: To investigate associations between electrocardiogram (ECG) and chest radiograph abnormalities and biochemical evidence of cardiac dysfunction (N-terminal pro-B-type natriuretic peptide and troponin T) in patients hospitalised with exacerbations of COPD at Waikato Hospital. METHODS: Independent examiners, blinded to NT-proBNP and troponin T levels, assessed ECG for tachycardia, atrial fibrillation, ventricular hypertrophy and ischaemic changes in 389 patients and chest radiographs for signs of heart failure in 350 patients. Associations between electrocardiographic and radiographic abnormalities with at least moderate interrater agreement and cardiac biomarkers were analysed. RESULTS: High NT-proBNP values (>220 pmol/L) were associated with atrial fibrillation (22 vs 6%), right ventricular hypertrophy (24 vs 15%), left ventricular hypertrophy (15 vs 4%), ischaemia (59 vs 33%) and cardiomegaly (42 vs 20%). High troponin T values (>0.03ug/L or high-sensitivity >50 ng/L) were associated with tachycardia (65 vs 41%), right ventricular hypertrophy (26 vs 15%) and ischaemia (60 vs 36%). None of the electrocardiographic or radiographic abnormalities was sensitive or specific for cardiac biomarker abnormalities. Ischaemia on ECG was the best indicator for raised NT-proBNP (sensitivity 59%, specificity 67%). Tachycardia and ischaemia were the best indicators of raised troponin T (sensitivity 65 and 60%, specificity 59 and 64% respectively). CONCLUSIONS: ECG and chest radiograph abnormalities have poor sensitivity and specificity for diagnosing acute cardiac dysfunction in exacerbations of COPD. Cardiac biomarkers provide additional diagnostic information about acute cardiac dysfunction in exacerbations of COPD.


Assuntos
Biomarcadores/sangue , Cardiopatias/diagnóstico , Cardiopatias/epidemiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Eletrocardiografia , Feminino , Cardiopatias/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Nova Zelândia/epidemiologia , Fragmentos de Peptídeos/sangue , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/sangue , Curva ROC , Radiografia , Sensibilidade e Especificidade , Troponina T/sangue
20.
Int J Sports Med ; 40(5): 336-343, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30887481

RESUMO

This study determined the training load (TL) and its relationship with high-intensity running performance across the season in professional soccer players. The TL, YoYo Intermittent Recovery Test Level 2 (YYIR 2) and repeated sprint ability (RSA) were monitored in 29 players (age 26.2±3.8 years, height 173.6±5.6 cm, body mass 68.5±8.6 kg). In the mid in-season (MS), Lucia TRIMP (TRIMPL) was inversely correlated with YYIR 2 (r=-0.6, p<0.05), with total distance (TD), work-rate (WR), low-intensity distance (LID) and player load (PL) showing correlation with YYIR 2 (r=0.81, 0.77, 0.88, 0.67; p<0.05) in the late in-season (LS). In pre-season (PS), TD, WR and moderate-intensity distance (MID) were correlated with YYIR 2 (r=0.65, 0.80, 0.83, p<0.05), whereas in early in-season (ES), TD, WR, LID were correlated with YYIR 2 performance (r=0.58, 0.67, 0.55, p<0.05). There was no significant relationship (p>0.05) between TL and RSA. The findings showed the volume, intensity and types of TL accrued influences the relationship with physical performance that suggest the significance of phase-specific monitoring of TL for maximizing performance in soccer players.


Assuntos
Desempenho Atlético , Corrida/fisiologia , Futebol/fisiologia , Carga de Trabalho , Adulto , Teste de Esforço , Humanos , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA