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1.
Nature ; 572(7770): 461-466, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31340216

RESUMO

Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space-use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively), and were also associated with significant increases in fishing effort. We conclude that pelagic sharks have limited spatial refuge from current levels of fishing effort in marine areas beyond national jurisdictions (the high seas). Our results demonstrate an urgent need for conservation and management measures at high-seas hotspots of shark space use, and highlight the potential of simultaneous satellite surveillance of megafauna and fishers as a tool for near-real-time, dynamic management.


Assuntos
Migração Animal , Pesqueiros/estatística & dados numéricos , Mapeamento Geográfico , Oceanos e Mares , Tubarões/fisiologia , Análise Espaço-Temporal , Animais , Densidade Demográfica , Medição de Risco , Tubarões/classificação , Navios , Fatores de Tempo
2.
Br J Sports Med ; 58(9): 470-476, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38331566

RESUMO

OBJECTIVE: To characterise the prevalence, incidence rate (IR) and burden of injuries in elite short-course triathletes over a 4-year training and competition period. METHODS: Fifty elite Australian triathletes were prospectively monitored for injury during four consecutive seasons (2018-2021). Injuries requiring medical attention were prospectively recorded and further subcategorised according to time loss. The IR and burden (injury IR×mean injury severity) were calculated per 365 athlete days, with sex differences in IR compared using IR ratios (IRR) from negative binomial regression models. RESULTS: Two hundred and sixty-six injuries were reported in 46 (92.0%) athletes, of which 67.3% resulted in time loss. The injury IR was 1.87 injuries per 365 athlete days (95% CI 1.70 to 2.80), and comparable between sexes (IRR 0.82, 95% CI 0.64 to 1.04, p=0.109). Most injuries (70.7%) were training related. The most frequently injured body sites were the ankle (15.8%), foot (12.4%) and lower leg (12.0%). Bone stress injuries (BSIs) were the most burdensome injury type with 31.38 days of time loss per 365 days (95% CI 24.42 to 38.34). Twenty athletes (40.0%) reported at least one bone stress injury (BSI) (range 0-3). The rate of BSIs in female athletes was three times greater compared with male athletes (IRR 2.99, 95% CI 1.26 to 7.07, p=0.013). CONCLUSION: Two-thirds of injuries reported in elite short-course triathletes resulted in time loss, with the majority occurring during training activities. Foot, ankle and other lower leg injuries had the highest incidence, with BSIs carrying the highest injury burden. The considerably higher rate of BSI observed in female athletes warrants consideration for future prevention strategies in female triathletes.


Assuntos
Traumatismos em Atletas , Natação , Humanos , Estudos Prospectivos , Feminino , Masculino , Traumatismos em Atletas/epidemiologia , Incidência , Prevalência , Adulto , Natação/lesões , Natação/estatística & dados numéricos , Austrália/epidemiologia , Corrida/lesões , Ciclismo/lesões , Adulto Jovem , Atletas/estatística & dados numéricos , Fraturas de Estresse/epidemiologia , Fatores Sexuais , Condicionamento Físico Humano/efeitos adversos
3.
Am Nat ; 201(4): 586-602, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36958006

RESUMO

AbstractUnifying models have shown that the amount of space used by animals (e.g., activity space, home range) scales allometrically with body mass for terrestrial taxa; however, such relationships are far less clear for marine species. We compiled movement data from 1,596 individuals across 79 taxa collected using a continental passive acoustic telemetry network of acoustic receivers to assess allometric scaling of activity space. We found that ectothermic marine taxa do exhibit allometric scaling for activity space, with an overall scaling exponent of 0.64. However, body mass alone explained only 35% of the variation, with the remaining variation best explained by trophic position for teleosts and latitude for sharks, rays, and marine reptiles. Taxon-specific allometric relationships highlighted weaker scaling exponents among teleost fish species (0.07) than sharks (0.96), rays (0.55), and marine reptiles (0.57). The allometric scaling relationship and scaling exponents for the marine taxonomic groups examined were lower than those reported from studies that had collated both marine and terrestrial species data derived using various tracking methods. We propose that these disparities arise because previous work integrated summarized data across many studies that used differing methods for collecting and quantifying activity space, introducing considerable uncertainty into slope estimates. Our findings highlight the benefit of using large-scale, coordinated animal biotelemetry networks to address cross-taxa evolutionary and ecological questions.


Assuntos
Organismos Aquáticos , Peixes , Animais , Comportamento de Retorno ao Território Vital
4.
Neurobiol Learn Mem ; 205: 107832, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37757953

RESUMO

Fear and extinction learning are thought to generate distinct and competing memory representations in the hippocampus. How these memory representations modulate the expression of appropriate behavioral responses remains unclear. To investigate this question, we used cholera toxin B subunit to retrolabel ventral hippocampal (vHPC) neurons projecting to the infralimbic cortex (IL) and basolateral amygdala (BLA) and then quantified c-Fos immediate early gene activity within these populations following expression of either contextual fear recall or contextual fear extinction recall. Fear recall was associated with increased c-Fos expression in vHPC projections to the BLA, whereas extinction recall was associated with increased activity in vHPC projections to IL. A control experiment was performed to confirm that the apparent shift in projection neuron activity was associated with extinction learning rather than mere context exposure. Overall, results indicate that hippocampal contextual fear and extinction memory representations differentially activate vHPC projections to IL and BLA. These findings suggest that hippocampal memory representations orchestrate appropriate behavioral responses through selective activation of projection pathways.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Complexo Nuclear Basolateral da Amígdala/fisiologia , Medo/fisiologia , Extinção Psicológica/fisiologia , Córtex Pré-Frontal/fisiologia , Hipocampo/fisiologia
5.
J Sports Sci ; 41(24): 2161-2168, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38390955

RESUMO

This study aimed to establish injury incidence rates (IIRs) and burden within an Australian male professional football club (n = 73) and to investigate longitudinal trends across five consecutive seasons (2016/17-2020/21). There was an overall IIR of 9.18 injuries per 1000 hours (h) (95% CI [7.89, 10.47]). The IIR was approximately seven times greater (rate ratio (RR): 6.85; 95% CI [5.13, 9.19]; p < 0.01) in matches (31.29 injuries per 1000 h; 95% CI [25.25, 37.33]) compared to training (4.49 injuries per 1000 h; 95% CI [3.51, 5.47]). The overall injury burden was 254.1 days lost per 1000 h (95% CI [220.9, 292.3]). Compared with the reference 2016/17 season, there were significant increases in minimal (RR: 6.94; 95% CI [1.27, 128.73]) and mild injuries (RR: 3.76; 95% CI [1.21, 16.39]) in season 2017/18 and decreases in moderate (RR: 0.40; 95% CI [0.19, 0.80]) and contact injuries (RR: 0.35; 95% CI [0.12, 0.90]) in season 2019/2020. Time-loss injury is common and represents a major burden in Australian male professional football, with injuries more frequently sustained during matches. Injury prevention practices should specifically be directed towards muscle/tendon and ligament injuries of the lower limb, particularly anterior cruciate ligament, ankle sprain and hamstring strain injuries.


Assuntos
Traumatismos em Atletas , Traumatismos da Perna , Rugby , Lesões dos Tecidos Moles , Humanos , Masculino , Traumatismos em Atletas/epidemiologia , Austrália/epidemiologia , Incidência
6.
Chemphyschem ; 23(4): e202100718, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-34902204

RESUMO

We herein report two salicyaldehyde-quinoxaline (HQS and HQSN) conjugates and a benzaldehyde-quinoxaline (QBN) conjugate to fabricate selective chemosensors for F- and Hg2+ in the micromolar range. This work demonstrates how sensing outcomes are affected by modulating proton acidity by introducing an electron donating group, -NEt2 , in the probe backbone. Interestingly, the un-substituted probe HQS can selectively detect F- , whereas HQSN and QBN are selective for Hg2+ . In order to gain insights into the mechanism of sensing, geometry optimizations have been carried out on QS(-1) , QS(-1) ⋅⋅⋅HF, QSN(-1) and QSN(-1) ⋅⋅⋅HF and the experimental data are validated in terms of free energy and pKa values. Detailed DFT and TD-DFT analyses provide ample support towards the mechanism of sensing of the analytes.


Assuntos
Colorimetria , Mercúrio , Benzaldeídos , Prótons , Quinoxalinas
7.
Biometals ; 35(3): 499-517, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35355153

RESUMO

A family of dioxidovanadium(V) complexes (1-4) of the type [Na(H2O)x]+[VVO2(HL1-4)]- (x = 4, 4.5 and 7) where HL2- represents the dianionic form of 2-hydroxybenzoylhydrazone of 2-hydroxyacetophenone (H2L1, complex 1), 2-hydroxy-5-methylacetophenone (H2L2, complex 2), 2-hydroxy-5-methoxyacetophenone (H2L3, complex 3) and 2-hydroxy-5-chloroacetophenone (H2L4, complex 4), have been synthesized and characterized by analytical and spectral methods. These complexes exhibited the potential abilities to suppress the erythrocytes carbonic anhydrase enzymatic activity in type 1 and type 2 diabetic patients (in vitro), promising antidiabetic activity against T2 diabetic mice (in vivo). They also exhibited significant cytotoxic activity against cervical cancer (SiHa) cells (in vitro) as the IC50 value of complexes 1, 2 and 4 is substantially lower than the value found for cisplatin while that of 3 is comparable and follow the order: 4 < 1 < 2 < 3 and can kill the cells by apoptosis via the generation of reactive oxygen species (ROS). The complexes are soluble both in water and octanol media and also non-toxic at working concentrations. The antidiabetic activity of these four complexes follows the order: 4 > 2 > 1 > 3 while both the carbonic anhydrase and cytotoxic activity follow the order: 4 > 1 > 2 > 3 suggesting that complex 4, containing electron withdrawing Cl atom is the most reactive while 3 with electron donating OCH3 group is the least reactive species. The molecular docking study on hCA-I and hCA-II demonstrates that complexes interact via hydrogen bonding as well as different types of π-stacking.


Assuntos
Antineoplásicos , Anidrases Carbônicas , Diabetes Mellitus Experimental , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Humanos , Hidrazonas/química , Hidrazonas/farmacologia , Hipoglicemiantes/farmacologia , Camundongos , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
10.
Molecules ; 27(9)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35566259

RESUMO

This work facilitates detection of bivalent copper ion by a simple Schiff base probe QNH based on a quinoxaline-naphthaldehyde framework. The detailed study in absorption spectroscopy and theoretical aspects and crystal study of the probe and probe-copper complex has been discussed. The detection limit of the probe in the presence of Cu2+ is 0.45 µM in HEPES-buffer/acetonitrile (3/7, v/v) medium for absorption study. The reversibility of the probe-copper complex has been investigated by EDTA. The selective visual detection of copper has been established also in gel form.


Assuntos
Colorimetria , Cobre , Colorimetria/métodos , Cobre/química , Corantes Fluorescentes/química , Quinoxalinas , Bases de Schiff/química
11.
J Neurosci ; 40(40): 7651-7667, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32873722

RESUMO

Stroke causes remodeling of vasculature surrounding the infarct, but whether and how vascular remodeling contributes to recovery are unclear. We established an approach to monitor and compare changes in vascular structure and blood flow with high spatiotemporal precision after photothrombotic infarcts in motor cortex using longitudinal 2-photon and multiexposure speckle imaging in mice of both sexes. A spatially graded pattern of vascular structural remodeling in peri-infarct cortex unfolded over the first 2 weeks after stroke, characterized by vessel loss and formation, and selective stabilization of a subset of new vessels. This vascular structural plasticity was coincident with transient activation of transcriptional programs relevant for vascular remodeling, reestablishment of peri-infarct blood flow, and large improvements in motor performance. Local vascular plasticity was strongly predictive of restoration of blood flow, which was in turn predictive of behavioral recovery. These findings reveal the spatiotemporal evolution of vascular remodeling after stroke and demonstrate that a window of heightened vascular plasticity is coupled to the reestablishment of blood flow and behavioral recovery. Our findings support that neovascularization contributes to behavioral recovery after stroke by restoring blood flow to peri-infarct regions. These findings may inform strategies for enhancing recovery from stroke and other types of brain injury.SIGNIFICANCE STATEMENT An improved understanding of neural repair could inform strategies for enhancing recovery from stroke and other types of brain injury. Stroke causes remodeling of vasculature surrounding the lesion, but whether and how the process of vascular remodeling contributes to recovery of behavioral function have been unclear. Here we used longitudinal in vivo imaging to track vascular structure and blood flow in residual peri-infarct cortex after ischemic stroke in mice. We found that stroke created a restricted period of heightened vascular plasticity that was associated with restoration of blood flow, which was in turn predictive of recovery of motor function. Therefore, our findings support that vascular remodeling facilitates behavioral recovery after stroke by restoring blood flow to peri-infarct cortex.


Assuntos
Movimento , Acidente Vascular Cerebral/fisiopatologia , Remodelação Vascular , Animais , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Circulação Cerebrovascular , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Acidente Vascular Cerebral/patologia , Transcriptoma
12.
Inorg Chem ; 60(9): 6446-6462, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33881858

RESUMO

Four new mononuclear/coordination polymeric (CP) zinc(II) complexes (1-4) of ferrocenyl/pyridyl-functionalized dithiocarbamate ligands, N-ferrocenylmethyl-N-butyl dithiocarbamate (L1), N-ferrocenylmethyl-N-ethylmorpholine dithiocarbamate (L2), N-ferrocenylmethyl-N-2-(diethylamino)ethylamine dithiocarbamate (L3), and N-4-methoxybenzyl-N-3-methylpyridyl dithiocarbamate (L4), have been synthesized and characterized by elemental analyses, IR, UV-vis, and 1H and 13C{1H} NMR spectroscopic techniques. The solid-state structures of complexes 1, 3, and 4 have been determined by single-crystal X-ray crystallography as well as powder X-ray diffraction. Single-crystal X-ray crystallography revealed a monomeric structure for complex 1 but 1D polymeric structures for complexes 3 and 4. In all complexes, dithiocarbamate ligands are bonded to the Zn(II) metal ion in a S^S chelating mode, and in the CPs, N atoms on the 2-(diethylamino)ethylamine and 3-pyridyl functionalities in the ligands on the neighboring molecules are also bonded to metal centers, leading to the formation of either a discrete tetrahedral molecule in 1 or 1D CP structures in 3 and 4. The Zn(II) metal centers in the polymeric structures exhibited either square-pyramidal or octahedral geometries. The supramolecular structures in these complexes are sustained via C-H···π (ZnCS2, chelate; 3 and 4), C-H···π, and H···H interactions. The catalytic performances of complexes have also been assessed in the Knoevenagel condensation and one-pot multicomponent reactions. Catalysis results showed that the CP 3 acts as a heterogeneous bifunctional catalyst with excellent transformation efficiency at low catalyst loading.

13.
Scand J Med Sci Sports ; 31(3): 691-701, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33124056

RESUMO

Sport science and medicine practitioners are interested in the relationships between training load, injury, and illness. The extent to which training preparedness is associated with workload-related injury and illness risk is debated. Therefore, this study applied multi-level mixed effect logistic regression to investigate time-dependent (±7- and ±28-day) relationships between training preparedness (fatigue, mood, motivation, soreness, stress, sleep duration, and quality), training load, injury, and illness in 536 elite and pre-elite female netball athletes. Absolute risk (AR ± 95% CI) of sustaining an injury (0.98 ± 0.06%, n = 1122 injuries, N = 254 athletes) or illness (1.09 ± 0.10%, n = 2881, N = 432 athletes) was calculated. All training preparedness variables combined resulted in an absolute risk of 0.88%-5.88% and 0.87%-20% for injury and illness, respectively. Injury and illness had significant (P < .05) bidirectional (ie, both increased and decreased) associations with physical (soreness) and physiological (sleep duration and quality), while illness also had negative (mood, motivation) and positive (stress) associations with psychological training preparedness variables. Low sleep duration in the 48-h period prior was associated (P = .005) with increased injury risk (OR = 0.91 ± 0.03; AR = 4.00%), while "very poor" sleep quality (OR = 0.59 ± 0.02; AR = 7.83%) or extremes of too little (<5 hours, OR = 1.01 ± 0.03; AR = 3.13%-14.29%) and too much (>10 hours, OR = 1.01 ± 0.03; AR = 2.61%-10.98%) sleep had bidirectional associations (P < .001) with an increased illness risk. Changes in training preparedness variables demonstrated bidirectional associations with injury and illness. These outcomes suggest that sport science and medicine practitioners should monitor sleep, physical, and psychological recovery status, to aid early detection and intervention regarding injury and illness symptomology.


Assuntos
Traumatismos em Atletas/fisiopatologia , Traumatismos em Atletas/psicologia , Condicionamento Físico Humano/fisiologia , Condicionamento Físico Humano/psicologia , Adolescente , Afeto , Traumatismos em Atletas/complicações , Fadiga/etiologia , Feminino , Humanos , Motivação , Mialgia/fisiopatologia , Análise de Componente Principal , Estudos Retrospectivos , Fatores de Risco , Sono/fisiologia , Estresse Psicológico/etiologia , Fatores de Tempo , Adulto Jovem
14.
Br J Sports Med ; 55(1): 38-45, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33199358

RESUMO

OBJECTIVES: Athlete health, training continuity and performance can be impeded as a result of Relative Energy Deficiency in Sport (RED-S). Here we report the point prevalence of symptoms described by the RED-S model in a mixed-sport cohort of Australian female athletes. METHODS: Elite and pre-elite female athletes (n=112) from eight sports completed validated questionnaires and underwent clinical assessment to assess the point prevalence of RED-S symptoms. Questionnaires included the Depression, Anxiety and Stress Questionnaire (DASS-21), Generalized Anxiety Disorder (GAD-7), Center for Epidemiological Studies Depression Scale (CES-D), SCOFF questionnaire for disordered eating, Low Energy Availability in Females Questionnaire (LEAF-Q), and a custom questionnaire on injury and illness. Clinical assessment comprised resting metabolic rate (RMR) assessment, dual-energy X-ray absorptiometry-derived body composition and bone mineral density, venous and capillary blood samples, and the Mini International Neuropsychiatric Interview (MINI 7.0.2). Descriptive prevalence statistics are presented. RESULTS: Almost all (80%) participants (age 19 (range 15-32) years; mass 69.5±10.3 kg; body fat 23.1%±5.0%) demonstrated at least one symptom consistent with RED-S, with 37% exhibiting between two and three symptoms. One participant demonstrated five symptoms. Impaired function of the immunological (28%, n=27), haematological (31%, n=33) and gastrointestinal (47%, n=51) systems were most prevalent. A moderate to high (11%-55%) prevalence of risk of low energy availability was identified via RMR and LEAF-Q, and identified mental illnesses were prevalent in one-third of the assessed cohort. CONCLUSION: Symptoms described by the RED-S model were prevalent in this cohort, supporting the need for improved awareness, monitoring and management of these symptoms in this population.


Assuntos
Comportamento Competitivo/fisiologia , Deficiência Energética Relativa no Esporte/epidemiologia , Absorciometria de Fóton , Adolescente , Adulto , Austrália/epidemiologia , Metabolismo Basal , Biomarcadores/sangue , Aptidão Cardiorrespiratória , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Entrevista Psicológica , Leptina/sangue , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Prevalência , Deficiência Energética Relativa no Esporte/diagnóstico , Deficiência Energética Relativa no Esporte/psicologia , Fatores de Risco , Adulto Jovem
15.
Int J Sport Nutr Exerc Metab ; 31(5): 427-437, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284349

RESUMO

The Low Energy Availability in Females Questionnaire (LEAF-Q) was validated to identify risk of the female athlete triad (triad) in female endurance athletes. This study explored the ability of the LEAF-Q to detect conditions related to low energy availability (LEA) in a mixed sport cohort of female athletes. Data included the LEAF-Q, SCOFF Questionnaire for disordered eating, dual-energy X-ray absorptiometry-derived body composition and bone mineral density, Mini International Neuropsychiatric Interview, blood pressure, and blood metabolic and reproductive hormones. Participants were grouped according to LEAF-Q score (≥8 or <8), and a comparison of means was undertaken. Sensitivity, specificity, and predictive values of the overall score and subscale scores were calculated in relation to the triad and biomarkers relevant to LEA. Fisher's exact test explored differences in prevalence of these conditions between groups. Seventy-five athletes (18-32 years) participated. Mean LEAF-Q score was 8.0 ± 4.2 (55% scored ≥8). Injury and menstrual function subscale scores identified low bone mineral density (100% sensitivity, 95% confidence interval [15.8%, 100%]) and menstrual dysfunction (80.0% sensitivity, 95% confidence interval [28.4%, 99.5%]), respectively. The gastrointestinal subscale did not detect surrogate markers of LEA. LEAF-Q score cannot be used to classify athletes as "high risk" of conditions related to LEA, nor can it be used as a surrogate diagnostic tool for LEA given the low specificity identified. Our study supports its use as a screening tool to rule out risk of LEA-related conditions or to create selective low-risk groups that do not need management as there were generally high negative predictive values (range 76.5-100%) for conditions related to LEA.


Assuntos
Metabolismo Energético , Síndrome da Tríade da Mulher Atleta/diagnóstico , Resistência Física , Adolescente , Adulto , Biomarcadores , Feminino , Humanos , Esportes , Inquéritos e Questionários , Adulto Jovem
16.
Chemistry ; 26(7): 1612-1623, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31793668

RESUMO

Two mononuclear uranyl complexes, [UO2 L1 ] (1) and [UO2 L2 ]⋅0.5 CH3 CN⋅0.25 CH3 OH (2), have been synthesized from two multidentate N3 O4 donor ligands, N,N'-bis(5-methoxysalicylidene)diethylenetriamine (H2 L1 ) and N,N'-bis(3-methoxysalicylidene)diethylenetriamine (H2 L2 ), respectively, and have been structurally characterized. Both complexes 1 and 2 showed a reversible UVI /UV couple at -1.571 and -1.519 V, respectively, in cyclic voltammetry. The reduction potential of the UVI /UV couple shifted towards more positive potential on addition of Li+ , Na+ , K+ , and Ag+ metal ions to acetonitrile solutions of complex 2, and the resulting potential was correlated with the Lewis acidity of the metal ions and was also justified by theoretical DFT calculations. No such shift in reduction potential was observed for complex 1. All four bimetallic products, [UO2 L2 Li0.5 ](ClO4 )0.5 (3), [UO2 L2 Na(ClO4 )]2 (4), [UO2 L2 Ag(NO3 )(H2 O)] (5), and [(UO2 L2 )2 K(H2 O)2 ]PF6 (6), formed on addition of the Li+ , Na+ , Ag+ , and K+ metal ions, respectively, to acetonitrile solutions of complex 2, were isolated in the solid state and structurally characterized by single-crystal X-ray diffraction. In all the species, the inner N3 O2 donor set of the ligand encompasses the equatorial plane of the uranyl ion and the outer open compartment with O2 O'2 donor sites hosts the second metal ion.

17.
Exerc Immunol Rev ; 26: 56-78, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32139349

RESUMO

PURPOSE: Habitual intense exercise may increase the incidence of upper respiratory symptoms (URS) in elite athletes. This study investigated whether immune gene expression could identify gene markers that discriminate athletes with a higher prevalence of URS. METHODS: This cross-sectional analysis of elite Australian athletes from various sports investigated whether athletes retrospectively reporting URS for two days or more in a month (n=38), had an altered immune gene expression profile compared with asymptomatic athletes (n=33). Peripheral blood samples were collected during Olympic selection events with corresponding URS data collected for the one-month period before sampling. Digital immune gene expression analysis was undertaken using the NanoString PanCancer Immune Profiling panel. RESULTS: Fifty immune genes were differentially expressed between the groups (p<0.05) and approximately 78% of these genes were more highly expressed in athletes reporting URS. Many of these genes were interferon-stimulated genes or genes involved in the Jak/Stat signalling pathway. Only interferon alpha inducible protein 27 (IFI27), an interferon stimulated gene involved in viral response, remained significantly higher in athletes reporting URS (log2 fold-difference=2.49, odds ratio 1.02 per unit increase; p<0.01) post-adjustment and discriminated athletes reporting URS from asymptomatic athletes with 78% accuracy. CONCLUSIONS: Expression of IFI27 could differentiate athletes reporting URS from asymptomatic athletes, a gene that is upregulated in the immune response to viral infection. Upregulation of viral signalling pathways provides novel information on the potential aetiology of URS in elite Olympic athletes.


Assuntos
Atletas , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/genética , Transcriptoma , Austrália , Estudos Transversais , Humanos , Proteínas de Membrana/genética , Estudos Retrospectivos
18.
Inorg Chem ; 59(16): 11417-11431, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32799477

RESUMO

Five novel zinc(II) and cadmium(II) ß-oxodithioester complexes, [Zn(L1)2] (1), [Zn(L2)2]n (2), [Zn(L3)2]n (3) [Cd(L1)2]n (4), [Cd(L2)2]n (5), with ß-oxodithioester ligands, where L1 = 3-(methylthio)-1-(thiophen-2-yl)-3-thioxoprop-1-en-1-olate, L2 = 3-(methylthio)-1-(pyridin-3-yl)-3-thioxoprop-1-en-1-olate, and L3 = 3-(methylthio)-1-(pyridin-4-yl)-3-thioxoprop-1-en-1-olate, were synthesized and characterized by elemental analysis, IR, UV-vis, and NMR spectroscopy (1H and 13C{1H}). The solid-state structures of all complexes were ascertained by single-crystal X-ray crystallography. The ß-oxodithioester ligands are bonded to Zn(II)/Cd(II) metal ions in an O∧S and N chelating/chelating-bridging fashion leading to the formation of 1D (in 2-4) and 2D (in 5) coordination polymeric structures, but complex 1 was obtained as a discrete tetrahedral molecule. Complex 4 crystallizes in the C2 chiral space group and has been studied using circular dichroism (CD) spectroscopy. The multidimensional assemblies in these complexes are stabilized by many important noncovalent C-H···π (ZnOSC3, chelate), π···π, C-H···π, and H···H interactions. The catalytic activities of 1-5 in reactions involving C-C and C-O bond formation have been studied, and the results indicated that complex 3 can be efficiently utilized as a heterogeneous bifunctional catalyst for the Knoevenagel condensation and multicomponent reactions to develop biologically important organic molecules. The luminescent properties of complexes were also studied. Interestingly, zinc complexes 1-3 showed strong lumniscent emission in the solid state, whereas cadmium complexes 4 and 5 exhibited bright luminescent emission in the solution phase. The semiconducting behavior of the complexes was studied by solid-state diffuse reflectance spectra (DRS), which showed optical band gaps in the range of 2.49-2.62 eV.

19.
Inorg Chem ; 59(2): 1125-1136, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31898893

RESUMO

Polyoxotungstate supported titanocene {Cp2Ti}2+ clusters H6{K8(Cp2Ti)2P4W24O88(PO4)2}·14H2O (1), H6[Na2P4W14O58(Cp2Ti)2]·12H2O (2), and H2[K6{Cp2Ti}{PW9O33(WO2)}2{NC5H3(COOK)2}(NC5H3(CH3)COOK)·22H2O] (3) have been synthesized, and their single crystal X-ray structures have revealed unprecedented and intriguing structural features. The synthesized compounds have been characterized by various spectroscopic techniques including UV-vis, cyclic voltammogram, NMR, ESI-MS, and inductive coupled plasma spectroscopy (ICP) in solution and also by IR, TGA, and diffuse reflectance in the solid state. Clusters 1 and 2 are rare examples of lacunary POM supported titanocene clusters obtained by incorporating various phosphorus heteroatoms to form elusive phosphotungstate assemblies, whereas 3 is an unprecedented organometallic as well as heteroleptic pyridyl functionalized POM. Clusters 1-3 show transient photocurrent ON/OFF behavior upon UV-light irradiation and also exhibit characteristic TiIV/III intravalence electron transfer. This behavior is also established by their cyclic voltammograms in mixed phosphate buffers (Na2HPO4/NaH2PO4) which show the evidence of POM supported {Cp2Ti}2+/+ species in their redox solution. Furthermore, ESR line broadening is also observed in these clusters at room temperature, a fact which also confirms the formation of partially reduced/oxidized {Cp2Ti}2+/+ species leading to TiIV/III intravalence electron transfers within all three clusters. The {Cp2Ti}2+ decorated polyoxometalate cluster 3 shows improved transient photocurrent behavior which may be due to the presence of pyridyl carboxyl ions which provide better surface contact for the cluster molecule through the carboxylate moiety to the ITO electrode.

20.
Scand J Med Sci Sports ; 30(3): 540-548, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31680306

RESUMO

Patellar tendinopathy (PT) is a leading cause of morbidity in jump-landing athletes. Landing mechanics are identified as a factor associated with PT and/or patellar tendon abnormality. This study aimed to identify key jump-landing variables associated with PT. Thirty-six junior elite basketball players (men n = 18, women n = 18) were recruited from a Basketball Australia development camp. Three-dimensional (3D) kinematic and ground reaction force (GRF) data during a stop-jump task were collected as well as ultrasound scans of the patellar tendons and recall history of training load data. Mixed-model factorial analyses of variance were used to determine any significant between-group differences. Of the 23 participants included for statistical analyses, 11 had normal bilateral patellar tendons (controls) and eight reported PT (currently symptomatic); however, the four participants categorized as asymptomatic with patellar tendon abnormality on diagnostic imaging were excluded from statistical analyses due to their small sample size. Athletes with PT displayed a similar knee flexion angle at initial foot-ground contact (IC) and hip extension strategy during a stop-jump horizontal landing. Despite a similar kinematic technique, athletes with PT utilized a strategy of a longer stance duration phase from IC to peak force. This strategy did not lead to those athletes with PT decreasing their peak vertical GRF nor patellar tendon force during landing but enabled these athletes to land with a lower rate of loading (control 59.2 ± 39.3 vs. PT 29.4 ± 33.7 BW.s-1). Athletes with PT still reported significantly reduced training volume (control 4.9 ± 1.8 vs PT 1.8 ± 1.1 sessions/wk; total training time/wk control 2.4 ± 1.0 vs PT 1.4 ± 1.1 h/wk).


Assuntos
Traumatismos em Atletas/fisiopatologia , Basquetebol/lesões , Ligamento Patelar/fisiopatologia , Tendinopatia/fisiopatologia , Adolescente , Atletas , Austrália , Fenômenos Biomecânicos , Transtornos Traumáticos Cumulativos/fisiopatologia , Teste de Esforço , Feminino , Humanos , Articulação do Joelho , Masculino
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