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1.
Proc Natl Acad Sci U S A ; 116(52): 26690-26696, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31843914

RESUMO

Climate shifts are key drivers of ecosystem change. Despite the critical importance of Antarctica and the Southern Ocean for global climate, the extent of climate-driven ecological change in this region remains controversial. In particular, the biological effects of changing sea ice conditions are poorly understood. We hypothesize that rapid postglacial reductions in sea ice drove biological shifts across multiple widespread Southern Ocean species. We test for demographic shifts driven by climate events over recent millennia by analyzing population genomic datasets spanning 3 penguin genera (Eudyptes, Pygoscelis, and Aptenodytes). Demographic analyses for multiple species (macaroni/royal, eastern rockhopper, Adélie, gentoo, king, and emperor) currently inhabiting southern coastlines affected by heavy sea ice conditions during the Last Glacial Maximum (LGM) yielded genetic signatures of near-simultaneous population expansions associated with postglacial warming. Populations of the ice-adapted emperor penguin are inferred to have expanded slightly earlier than those of species requiring ice-free terrain. These concerted high-latitude expansion events contrast with relatively stable or declining demographic histories inferred for 4 penguin species (northern rockhopper, western rockhopper, Fiordland crested, and Snares crested) that apparently persisted throughout the LGM in ice-free habitats. Limited genetic structure detected in all ice-affected species across the vast Southern Ocean may reflect both rapid postglacial colonization of subantarctic and Antarctic shores, in addition to recent genetic exchange among populations. Together, these analyses highlight dramatic, ecosystem-wide responses to past Southern Ocean climate change and suggest potential for further shifts as warming continues.

2.
Spinal Cord ; 59(6): 675-683, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33024297

RESUMO

STUDY DESIGN: Quantitative cross-sectional study. OBJECTIVES: Evaluate the test-retest reliability and the construct validity of inertial measurement units (IMU) to characterize spatiotemporal gait parameters in individuals with SCI. SETTING: Two SCI rehabilitation centers in Canada. METHODS: Eighteen individuals with SCI participated in two evaluation sessions spaced 2 weeks apart. Fifteen able-bodied individuals were also recruited. Participants walked 20 m overground under five conditions that challenged balance to varying degrees. Five IMU were attached to the lower-extremities and the sacrum to collect the mean and the coefficient of variation of five gait parameters (gait cycle time, double-support percentage, cadence, stride length, stride velocity). Intra-class correlation coefficients (ICC) were used to evaluate the test-retest reliability. Linear mixed-effects models were used to compare the five walking conditions to evaluate known-group validity while Spearman's correlation coefficients were used to characterize the level of association between gait parameters and the Mini BESTest (MBT). RESULTS: Cadence was reliable across all walking conditions. Reliability was higher for the mean (ICC = 0.55-0.98) of the parameters compared to their coefficient of variation (ICC = 0.16-0.97). Cadence collected with IMU had construct validity as their values differed across walking conditions and groups of participants. The coefficient of variation was generally better than the mean to show differences across the five walking conditions. The MBT was moderately to strongly associated with mean cadence (ρ ≥ 0.498) and its coefficient of variation (ρ ≤ -0.49) during most walking conditions. CONCLUSIONS: IMU provide reliable and valid measurements of gait parameters in ambulatory individuals with SCI.


Assuntos
Traumatismos da Medula Espinal , Dispositivos Eletrônicos Vestíveis , Estudos Transversais , Marcha , Humanos , Reprodutibilidade dos Testes , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/diagnóstico , Caminhada
3.
J Neuroeng Rehabil ; 18(1): 57, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33794948

RESUMO

BACKGROUND: Individuals with an incomplete spinal cord injury (iSCI) are highly susceptible to falls during periods of walking or standing. We recently reported the findings of a novel intervention combining functional electrical stimulation with visual feedback balance training (FES + VFBT) on standing balance abilities among five individuals with motor iSCI. However, the previous publication did not report the perceived impact of the intervention on the participants' lives. In this report, the experiences of these five individuals with incomplete spinal cord injury (iSCI) who had recently completed the four-week balance training program are described. METHODS: Five individuals with a motor iSCI took part in this study. Each individual was at least 12 months post-injury, capable of unassisted standing for 60 s and had a Berg Balance Scale Score < 46. Participants completed twelve sessions of a novel balance intervention combining closed-loop functional electrical stimulation with visual feedback balance training (FES + VFBT). Participants received visual feedback regarding their centre of pressure position as they completed balance-training exercises while FES was applied to the ankle plantarflexors and dorsiflexors bilaterally. Semi-structured interviews were conducted after completion of the balance training intervention and eight-weeks post-training to understand participant's experiences. Categories and themes were derived from the transcripts using conventional content analysis. RESULTS: Three themes were identified from the collected transcripts: (1) Perceived benefits across International Classification of Functioning, Disability and Health levels; (2) Change in perceived fall risk and confidence; (3) Motivation to keep going. CONCLUSIONS: Participation in the FES + VFBT program resulted in perceived benefits that led to meaningful improvements in activities of daily living. Following completion of the training, individuals felt they still had the capacity to improve. Individuals felt they had increased their balance confidence, while a few participants also reported a decrease in their risk of falling. The inclusion of qualitative inquiry allows for the evaluation of the meaningfulness of an intervention and its perceived impact on the lives of the participants. TRIAL REGISTRATION: NCT04262414 (retrospectively registered February 10, 2020).


Assuntos
Atitude , Terapia por Estimulação Elétrica/métodos , Estimulação Elétrica , Terapia por Exercício/métodos , Retroalimentação Sensorial , Equilíbrio Postural , Traumatismos da Medula Espinal/reabilitação , Acidentes por Quedas/prevenção & controle , Atividades Cotidianas , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Reabilitação Neurológica , Satisfação do Paciente , Pesquisa Qualitativa , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia , Posição Ortostática , Caminhada
4.
Mol Phylogenet Evol ; 131: 72-79, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30367976

RESUMO

Human impacts have substantially reduced avian biodiversity in many parts of the world, particularly on isolated islands of the Pacific Ocean. The New Zealand archipelago, including its five subantarctic island groups, holds breeding grounds for a third of the world's penguin species, including several representatives of the diverse crested penguin genus Eudyptes. While this species-rich genus has been little studied genetically, recent population estimates indicate that several Eudyptes taxa are experiencing demographic declines. Although crested penguins are currently limited to southern regions of the New Zealand archipelago, prehistoric fossil and archaeological deposits suggest a wider distribution during prehistoric times, with breeding ranges perhaps extending to the North Island. Here, we analyse ancient, historic and modern DNA sequences to explore two hypotheses regarding the recent history of Eudyptes in New Zealand, testing for (1) human-driven extinction of Eudyptes lineages; and (2) reduced genetic diversity in surviving lineages. From 83 prehistoric bone samples, each tentatively identified as 'Eudyptes spp.', we genetically identified six prehistoric penguin taxa from mainland New Zealand, including one previously undescribed genetic lineage. Moreover, our Bayesian coalescent analyses indicated that, while the range of Fiordland crested penguin (E. pachyrhynchus) may have contracted markedly over the last millennium, genetic DNA diversity within this lineage has remained relatively constant. This result contrasts with human-driven biodiversity reductions previously detected in several New Zealand coastal vertebrate taxa.


Assuntos
DNA Antigo/análise , Variação Genética , Filogenia , Spheniscidae/genética , Animais , Teorema de Bayes , Biodiversidade , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fósseis , Haplótipos/genética , Humanos , Nova Zelândia , Oceano Pacífico , Dinâmica Populacional , Spheniscidae/classificação , Fatores de Tempo
5.
PLoS One ; 17(10): e0275106, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36223344

RESUMO

Erect-crested penguins are the least studied of all penguins. They breed on two isolated subantarctic island groups, the Antipodes and Bounty Islands. Sporadic nest counts indicate a dramatic decline in numbers of erect-crested penguins over the last 50 years. Here we present data from a study undertaken in 1998 on the breeding biology, behavior and hormones of erect-crested penguins. It represents, even today, by far the most detailed data available on this species. The penguins exhibited extreme reversed egg-size dimorphism, whereby the first-laid A-egg was much smaller than the second-laid B-egg. A-eggs were lost before (42.3%) or on (37.8%) the day the B-egg was laid, and none survived more than 7 days after that. The penguins were in a low state of reproductive readiness, as evidenced by low levels of copulation, fighting, and testosterone in males during the courtship/laying period when, curiously, plasma levels of testosterone were at least as high in females. The laying interval (5.4 days) is the longest recorded for any penguin species, and incubation was highly variable until clutch completion. Most nests (91.2%) contained no nesting material and eggs were laid directly onto the ground. A-eggs were lost mainly by rolling out of the nest. However, even when prevented from doing so by an experimental manipulation, A-eggs survived no longer than those in control nests. Testosterone levels in males increased after clutch completion, when they remained in attendance at the nest for up to 13 days, despite females assuming most of the incubation duties. The bills of males were significantly larger than those of females and probably help with guarding the nest. We discuss explanations for obligate brood reduction in crested penguins and the options for conservation in light of our census results, which indicate that this enigmatic penguin species could be in trouble.


Assuntos
Spheniscidae , Animais , Biologia , Ovos , Feminino , Masculino , Comportamento de Nidação , Reprodução , Testosterona
6.
Mol Cell Biochem ; 348(1-2): 109-15, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21080035

RESUMO

Prothrombin interacts with phosphatidylserine containing platelet membranes via its N-terminal, γ-carboxyglutamate (gla) residue-rich domain. Once bound it is cleaved to form the active protease, thrombin (factor IIa). Human prothrombin was cleaved with cathepsin G in the absence of calcium and magnesium ions. Under these conditions, the gla domain was removed. Phospholipid protected the protein from this proteolytic event, and this suggests that a conformational change may be induced by interaction with phospholipids. Binding of prothrombin to a surface containing 20% phosphatidylserine/80% phosphatidylcholine was detected by surface plasmon resonance, whereas no interaction with gla-domainless prothrombin was observed. Binding of intact prothrombin in the presence of calcium ions showed complex association kinetics, suggesting multiple modes of initial interaction with the surface. The kinetics of the dissociation phase could be fitted to a two-phase, exponential decay. This implies that there are at least two forms of the protein on the surface one of which dissociates tenfold more slowly than the other. Taken together, these data suggest that, on binding to a membrane surface, prothrombin undergoes a conformational change to a form which binds more tightly to the membrane.


Assuntos
Bicamadas Lipídicas , Fosfatidilcolinas/metabolismo , Fosfatidilserinas/metabolismo , Protrombina/metabolismo , Trombina/metabolismo , Ácido 1-Carboxiglutâmico/metabolismo , Cálcio/metabolismo , Catepsina G/metabolismo , Humanos , Cinética , Modelos Biológicos , Conformação Molecular , Fosfatidilcolinas/química , Fosfatidilserinas/química , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Processamento de Proteína Pós-Traducional , Protrombina/química , Ressonância de Plasmônio de Superfície
7.
Biomolecules ; 11(12)2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34944534

RESUMO

There is a need for new antimicrobial systems due to increased global resistance to current antimicrobials. Pomegranate rind extract (PRE) and Zn (II) ions both possess a level of antimicrobial activity and work has previously shown that PRE/Zn (II) in combination possesses synergistic activity against Herpes simplex virus and Micrococcus luteus. Here, we determined whether such synergistic activity extended to other, more pathogenic, bacteria. Reference strains of methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa were cultured and subjected to challenge by PRE, Zn (II), or PRE + Zn (II), in time-kill assays. Data were obtained independently by two researchers using different PRE preparations. Statistically significant synergistic activity for PRE + Zn (II) was shown for all four bacterial strains tested compared to untreated controls, although the extent of efficacy and timescales varied. Zn (II) exerted activity and at 1 h, it was not possible to distinguish with PRE + Zn (II) combination treatment in all cases. PRE alone showed low activity against all four bacteria. Reproducible synergistic bactericidal activity involving PRE and Zn (II) has been confirmed. Potential mechanisms are discussed. The development of a therapeutic system that possesses demonstrable antimicrobial activity is supported which lends itself particularly to topical delivery applications, for example MRSA infections.


Assuntos
Escherichia coli/crescimento & desenvolvimento , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Extratos Vegetais/farmacologia , Punica granatum/química , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus epidermidis/crescimento & desenvolvimento , Zinco/farmacologia , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Extratos Vegetais/química , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos
8.
Front Neurol ; 11: 680, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32793101

RESUMO

Individuals with an incomplete spinal cord injury (iSCI) are highly susceptible to falls during walking or standing. Our objective was to evaluate a therapeutic tool for standing balance that combined functional electrical stimulation, applied bilaterally to the plantarflexors and dorsiflexors, with visual feedback balance training (FES+VFBT). Five adults with iSCI completed 12 FES+VFBT sessions over 4 weeks. During the training sessions, participants completed each of the four balance exercises twice. Visual feedback of the center-of-pressure (COP) location was provided as participants completed the balance exercises and received FES to assist with performance of the exercises. A closed-loop FES system was used in which the COP was continually monitored and the level of electrical current administered was automatically adjusted. Balance abilities were assessed pre- and post- training using clinical balance scales (i.e., Berg Balance Scale, Mini-Balance Evaluation Systems Test, and Activities-specific Balance Confidence Scale) and biomechanical assessments (i.e., postural sway measures and limits of stability test during standing). User acceptability was explored through semi-structured interviews. Improvements were seen for four of the five participants on at least one of the clinical scales following completion of the training intervention. All participants showed greater maximal COP excursion area during the limits of stability test after the training intervention, whereas only one participant demonstrated a reduction in postural sway. Specific components of FES+VFBT, including the ability to safely practice challenging balance exercises, were deemed important by the participants. These results suggest that FES+VFBT has potential as an intervention for standing balance after iSCI.

9.
Gigascience ; 8(9)2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31531675

RESUMO

BACKGROUND: Penguins (Sphenisciformes) are a remarkable order of flightless wing-propelled diving seabirds distributed widely across the southern hemisphere. They share a volant common ancestor with Procellariiformes close to the Cretaceous-Paleogene boundary (66 million years ago) and subsequently lost the ability to fly but enhanced their diving capabilities. With ∼20 species among 6 genera, penguins range from the tropical Galápagos Islands to the oceanic temperate forests of New Zealand, the rocky coastlines of the sub-Antarctic islands, and the sea ice around Antarctica. To inhabit such diverse and extreme environments, penguins evolved many physiological and morphological adaptations. However, they are also highly sensitive to climate change. Therefore, penguins provide an exciting target system for understanding the evolutionary processes of speciation, adaptation, and demography. Genomic data are an emerging resource for addressing questions about such processes. RESULTS: Here we present a novel dataset of 19 high-coverage genomes that, together with 2 previously published genomes, encompass all extant penguin species. We also present a well-supported phylogeny to clarify the relationships among penguins. In contrast to recent studies, our results demonstrate that the genus Aptenodytes is basal and sister to all other extant penguin genera, providing intriguing new insights into the adaptation of penguins to Antarctica. As such, our dataset provides a novel resource for understanding the evolutionary history of penguins as a clade, as well as the fine-scale relationships of individual penguin lineages. Against this background, we introduce a major consortium of international scientists dedicated to studying these genomes. Moreover, we highlight emerging issues regarding ensuring legal and respectful indigenous consultation, particularly for genomic data originating from New Zealand Taonga species. CONCLUSIONS: We believe that our dataset and project will be important for understanding evolution, increasing cultural heritage and guiding the conservation of this iconic southern hemisphere species assemblage.


Assuntos
Genoma , Spheniscidae/genética , Animais , Evolução Molecular , Filogenia
10.
FEBS J ; 275(8): 1742-50, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18331357

RESUMO

Eppin has two potential protease inhibitory domains: a whey acid protein or four disulfide core domain and a Kunitz domain. The protein is also reported to have antibacterial activity against Gram-negative bacteria. Eppin and its whey acid protein and Kunitz domains were expressed in Escherichia coli and their ability to inhibit proteases and kill bacteria compared. The Kunitz domain inhibits elastase (EC 3.4.21.37) to a similar extent as intact eppin, whereas the whey acid protein domain has no such activity. None of these fragments inhibits trypsin (EC 3.4.21.4) or chymotrypsin (EC 3.4.21.1) at the concentrations tested. In a colony forming unit assay, both domains have some antibacterial activity against E. coli, but this was not to the same degree as intact eppin or the two domains together. When bacterial respiratory electron transport was measured using a 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide assay, eppin and its domains caused an increase in the rate of respiration. This suggests that the mechanism of cell killing may be partly through the permeablization of the bacterial inner membrane, resulting in uncoupling of respiratory electron transport and consequent collapse of the proton motive force. Thus, we conclude that although both of eppin's domains are involved in the protein's antibacterial activity, only the Kunitz domain is required for selective protease inhibition.


Assuntos
Proteínas Secretadas Inibidoras de Proteinases/química , Proteínas Secretadas Inibidoras de Proteinases/metabolismo , Motivos de Aminoácidos , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Dicroísmo Circular , Transporte de Elétrons , Escherichia coli/efeitos dos fármacos , Humanos , Proteínas Secretadas Inibidoras de Proteinases/genética , Proteínas Secretadas Inibidoras de Proteinases/farmacologia
11.
Accid Anal Prev ; 40(1): 200-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18215549

RESUMO

Using cross-sectional time series data for the 50 states and Washington, DC, covering the period 1975-2004, we estimate fixed effects regression models that examine the effects of universal and partial helmet laws on three different motorcyclist fatality rates, while controlling for other state policies and characteristics. Depending on the particular measure that is employed, states with universal helmet laws have motorcyclist fatality rates that are on average 22-33% lower in comparison to the experience with no helmet law. Additionally, partial coverage helmet laws are associated with reductions in motorcyclist fatality rates of 7-10%, on average.


Assuntos
Acidentes de Trânsito/mortalidade , Condução de Veículo/legislação & jurisprudência , Dispositivos de Proteção da Cabeça/estatística & dados numéricos , Motocicletas/legislação & jurisprudência , Estudos Transversais , Dispositivos de Proteção da Cabeça/tendências , Humanos , Mortalidade/tendências , Estados Unidos/epidemiologia
12.
PLoS One ; 13(8): e0198688, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30157174

RESUMO

Migratory species often roam vast distances bringing them into contact with diverse conditions and threats that could play significant roles in their population dynamics. This is especially true if long-range travels occur within crucial stages of a species' annual life-cycle. Crested penguins, for example, usually disperse over several hundreds of kilometres after completing the energetically demanding breeding season and in preparation for the costly annual moult. A basic understanding of crested penguins' pre-moult dispersal is therefore paramount in order to be able to assess factors affecting individual survival. The Fiordland penguin, or Tawaki, the only crested penguin species breeding on the New Zealand mainland, is currently one of the least studied and rarest penguin species in the world. We successfully satellite tracked the pre-moult dispersal of 17 adult Tawaki from a single colony located in the species' northern breeding distribution. Over the course of 8-10 weeks the penguins travelled up to 2,500 km away from their breeding colony, covering total swimming distances of up to 6,800 km. During outbound travels all penguins headed south-west within a well-defined corridor before branching out towards two general trip destinations. Birds leaving in late November travelled towards the Subtropical Front some 800 km south of Tasmania, whereas penguins that left in December headed further towards the subantarctic front. Using K-select analysis we examined the influence of oceanographic factors on the penguins' dispersal. Water depth, surface current velocity and sea level anomalies had the greatest influence on penguin movements at the subantarctic Front, while sea surface temperature and chlorophyll a concentration were key for birds travelling to the subtropical front. We discuss our findings in the light of anthropogenic activities (or lack thereof) in the regions visited by the penguins as well as the potential consequences of Tawaki pre-moult dispersal for the species' breeding distribution on the New Zealand mainland.


Assuntos
Migração Animal/fisiologia , Muda/fisiologia , Spheniscidae/fisiologia , Animais , Mapeamento Geográfico , Nova Zelândia , Dinâmica Populacional , Reprodução/fisiologia , Comunicações Via Satélite , Estações do Ano , Telemetria
13.
Am J Public Health ; 97(11): 2063-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17901447

RESUMO

OBJECTIVES: We assessed the implications for motorcyclist safety of recent repeals of universal helmet laws in 6 US states. METHODS: We examined cross-sectional time-series data from the 50 states and the District of Columbia for the period 1975 through 2004. RESULTS: On average, when compared to state experience with no helmet mandate, universal helmet laws were associated with an 11.1% reduction in motorcyclist fatality rates, whereas rates in states with partial coverage statutes were not statistically different from those with no helmet law. Furthermore, in the states in which recent repeals of universal coverage have been instituted, the motorcyclist fatality rate increased by an average of 12.2% over what would have been expected had universal coverage been maintained. Since 1997, an additional 615 motorcyclist fatalities have occurred in these states as a result of these changes in motorcycle helmet laws. CONCLUSIONS: Motorcyclist safety has been compromised in the states that have repealed universal coverage and is likely to be compromised in other states that abandon these statutes.


Assuntos
Acidentes de Trânsito/mortalidade , Dispositivos de Proteção da Cabeça , Motocicletas , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Análise de Regressão , Segurança , Estados Unidos/epidemiologia
14.
J Safety Res ; 38(3): 329-36, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17617242

RESUMO

PROBLEM: The trend in state mandatory motorcycle helmet laws is away from universal coverage to partial coverage statutes that require only young riders to wear a helmet. Among partial coverage states substantial variation exists in this age requirement. How effective are motorcycle helmet laws at reducing young motorcyclist fatalities? METHOD: The dependent variable is the number of motorcyclist fatalities 15-20 years of age. Fixed effects negative binomial regression models are estimated using panel data for all 50 states and Washington DC, for the period 1975-2004. RESULTS: Universal helmet laws are associated with fatality rates that are 31% lower among motorcyclists 15-20 years of age. In contrast, partial coverage laws targeting young motorcyclists are statistically unrelated to a reduction in the fatality rates of this age group. DISCUSSION: The long-term consequence of the move away from universal helmet laws will be an increased level of risk faced by young motorcyclists. In many states, mandatory motorcycle helmet laws are not protecting even young riders.


Assuntos
Acidentes de Trânsito/mortalidade , Dispositivos de Proteção da Cabeça/estatística & dados numéricos , Motocicletas/legislação & jurisprudência , Adolescente , Adulto , Humanos , Estados Unidos/epidemiologia
15.
Eur J Pharm Biopharm ; 112: 30-37, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27867111

RESUMO

Coadministered pomegranate rind extract (PRE) and zinc (II) produces a potent virucidal activity against Herpes simplex virus (HSV); however, HSV infections are also associated with localised inflammation and pain. Here, the objective was to determine the anti-inflammatory activity and relative depth penetration of PRE, total pomegranate tannins (TPT) and zinc (II) in skin, ex vivo. PRE, TPT and ZnSO4 were dosed onto freshly excised ex vivo porcine skin mounted in Franz diffusion cells and analysed for COX-2, as a marker for modulation of the arachidonic acid inflammation pathway, by Western blotting and immunohistochemistry. Tape stripping was carried out to construct relative depth profiles. Topical application of PRE to ex vivo skin downregulated expression of COX-2, which was significant after just 6h, and maintained for up to 24h. This was achieved with intact stratum corneum, proving that punicalagin penetrated skin, further supported by the depth profiling data. When PRE and ZnSO4 were applied together, statistically equal downregulation of COX-2 was observed when compared to the application of PRE alone; no effect followed the application of ZnSO4 alone. TPT downregulated COX-2 less than PRE, indicating that tannins alone may not be entirely responsible for the anti-inflammatory activity of PRE. Punicalagin was found throughout the skin, in particular the lower regions, indicating appendageal delivery as a significant route to the viable epidermis. Topical application of TPT and PRE had significant anti-inflammatory effects in ex vivo skin, confirming that PRE penetrates the skin and modulates COX-2 regulation in the viable epidermis. Pomegranates have potential as a novel approach in ameliorating the inflammation and pain associated with a range of skin conditions, including cold sores and herpetic stromal keratitis.


Assuntos
Anti-Inflamatórios/administração & dosagem , Lythraceae/química , Extratos Vegetais/administração & dosagem , Pele/efeitos dos fármacos , Animais , Western Blotting , Ciclo-Oxigenase 2/metabolismo , Taninos Hidrolisáveis/administração & dosagem , Taninos Hidrolisáveis/farmacocinética , Técnicas In Vitro , Pele/enzimologia , Pele/metabolismo , Suínos , Zinco/administração & dosagem , Zinco/farmacocinética
17.
PLoS One ; 12(6): e0179291, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28665969

RESUMO

BACKGROUND: There is a clinical need for new therapeutic products against Herpes simplex virus (HSV). The pomegranate, fruit of the tree Punica granatum L, has since ancient times been linked to activity against infection. This work probed the activity of pomegranate rind extract (PRE) and co-administered zinc (II) ions. MATERIALS AND METHODS: PRE was used in conjunction with zinc (II) salts to challenge HSV-1 and aciclovir-resistant HSV in terms of virucidal plaque assay reduction and antiviral activities in epithelial Vero host cells. Cytotoxicity was determined by the MTS assay using a commercial kit. RESULTS: Zinc sulphate, zinc citrate, zinc stearate and zinc gluconate demonstrated similar potentiated virucidal activity with PRE against HSV-1 by up to 4-fold. A generally parabolic relationship was observed when HSV-1 was challenged with PRE and varying concentrations of ZnSO4, with a maximum potentiation factor of 5.5. Punicalagin had 8-fold greater virucidal activity than an equivalent mass of PRE. However, antiviral data showed that punicalagin had significantly lower antiviral activity compared to the activity of PRE (EC50 = 0.56 µg mL-1) a value comparable to aciclovir (EC50 = 0.18 µg mL-1); however, PRE also demonstrated potency against aciclovir-resistant HSV (EC50 = 0.02 µg mL-1), whereas aciclovir showed no activity. Antiviral action of PRE was not influenced by ZnSO4. No cytotoxicity was detected with any test solution. CONCLUSIONS: The potentiated virucidal activity of PRE by coadministered zinc (II) has potential as a multi-action novel topical therapeutic agent against HSV infections, such as coldsores.


Assuntos
Aciclovir/farmacologia , Antivirais/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Lythraceae/química , Extratos Vegetais/farmacologia , Compostos de Zinco/farmacologia , Animais , Antivirais/administração & dosagem , Chlorocebus aethiops , Citotoxicidade Imunológica/efeitos dos fármacos , Farmacorresistência Viral , Sinergismo Farmacológico , Ácido Elágico/farmacologia , Herpesvirus Humano 1/crescimento & desenvolvimento , Herpesvirus Humano 2/crescimento & desenvolvimento , Extratos Vegetais/administração & dosagem , Células Vero , Ensaio de Placa Viral , Compostos de Zinco/administração & dosagem
18.
Eur J Pharm Sci ; 96: 99-106, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27516148

RESUMO

Coadministration of pomegranate rind extract (PRE) and zinc (II) ions has recently been reported as a potential new topical treatment for Herpes simplex virus (HSV) infections. In the current work we examined the in vitro topical delivery of punicalagin (major phytochemical of PRE) and zinc from hydrogels across epithelial membranes that can become infected with HSV. Porcine epidermal, buccal and vaginal mucous membranes were excised and mounted in Franz diffusion cells and dosed with a simple hydrogel containing PRE and zinc sulphate (ZnSO4). The permeation of punicalagin and zinc were determined by HPLC and ICPMS respectively; punicalagin was also determined in the basal layers by reverse tape stripping. Receptor phases from the epidermal membrane experiment were also used to challenge HSV-1 in Vero host cells, and ex vivo porcine skin was used to probe COX-2 modulation. Punicalagin and zinc permeated each of the three test membranes, with significantly greater amounts of both delivered across the epidermal membrane. The amounts of punicalagin permeating the buccal and vaginal membranes were similar, although the amount of zinc permeating the vaginal membrane was comparatively very large - it is known that zinc interacts with vaginal mucosa. The punicalagin recovered by reverse tape stripping of the epidermal, buccal and vaginal membranes gave 0.47±0.016, 0.45±0.052 and 0.51±0.048nMcm-2 respectively, and were statistically the same (p<0.05). A 2.5 log reduction was achieved against HSV-1 using diffusion cell receptor phase, and COX-2 expression was reduced by 64% in ex vivo skin after 6h. Overall, a hydrogel containing 1.25mgmL-1 PRE and 0.25M ZnSO4 was able to topically deliver both the major bioactive compound within PRE and Zn (II) across all membranes and into the site specific region of Herpes simplex vesicular clusters, while maintaining potentiated virucidal and anti-inflammatory properties. This novel therapeutic system therefore has potential for the topical treatment of HSV infections.


Assuntos
Anti-Inflamatórios/administração & dosagem , Antivirais/administração & dosagem , Hidrogéis/administração & dosagem , Taninos Hidrolisáveis/administração & dosagem , Sulfato de Zinco/administração & dosagem , Animais , Anti-Inflamatórios/farmacologia , Antivirais/farmacologia , Chlorocebus aethiops , Ciclo-Oxigenase 2/metabolismo , Feminino , Herpes Simples , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 1/crescimento & desenvolvimento , Hidrogéis/farmacologia , Taninos Hidrolisáveis/farmacologia , Derivados da Hipromelose , Técnicas In Vitro , Mucosa/efeitos dos fármacos , Mucosa/metabolismo , Mucosa/virologia , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/virologia , Suínos , Células Vero , Sulfato de Zinco/farmacologia
19.
PeerJ ; 5: e3272, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28533952

RESUMO

Climate change is a global issue with effects that are difficult to manage at a regional scale. Yet more often than not climate factors are just some of multiple stressors affecting species on a population level. Non-climatic factors-especially those of anthropogenic origins-may play equally important roles with regard to impacts on species and are often more feasible to address. Here we assess the influence of climate change on population trends of the endangered Yellow-eyed penguin (Megadyptes antipodes) over the last 30 years, using a Bayesian model. Sea surface temperature (SST) proved to be the dominating factor influencing survival of both adult birds and fledglings. Increasing SST since the mid-1990s was accompanied by a reduction in survival rates and population decline. The population model showed that 33% of the variation in population numbers could be explained by SST alone, significantly increasing pressure on the penguin population. Consequently, the population becomes less resilient to non-climate related impacts, such as fisheries interactions, habitat degradation and human disturbance. However, the extent of the contribution of these factors to declining population trends is extremely difficult to assess principally due to the absence of quantifiable data, creating a discussion bias towards climate variables, and effectively distracting from non-climate factors that can be managed on a regional scale to ensure the viability of the population.

20.
Am J Public Health ; 96(11): 1949-54, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17018824

RESUMO

State seat belt laws have increased use rates and have reduced traffic fatalities, but tremendous variation exists in the laws. New Hampshire does not have a law, and 30 states have only secondary enforcement laws. Whereas primary enforcement allows an officer to issue a citation for any infraction, secondary enforcement permits a citation only if a motorist is stopped for another infraction first. We performed a cross-sectional time-series analysis of the impact of upgrading to primary enforcement on belt use rates for 47 states and the District of Columbia from 1991 to 2003. Our results suggest that states with secondary enforcement laws could increase belt use by 10 percentage points and improve public safety considerably by upgrading to primary enforcement.


Assuntos
Condução de Veículo/legislação & jurisprudência , Aplicação da Lei/métodos , Política Pública , Segurança/legislação & jurisprudência , Cintos de Segurança/legislação & jurisprudência , Cintos de Segurança/estatística & dados numéricos , Governo Estadual , Adolescente , Adulto , Idoso , Condução de Veículo/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polícia , Probabilidade , Estudos de Amostragem , Estados Unidos
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