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1.
Proc Biol Sci ; 290(2003): 20231170, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37464761

RESUMO

Population-level shifts in reproductive phenology in response to environmental change are common, but whether individual-level responses are modified by demographic and genetic factors remains less well understood. We used mixed models to quantify how reproductive timing varied across 1772 female southern elephant seals (Mirounga leonina) breeding at Marion Island in the Southern Ocean (1989-2019), and to identify the factors that correlate with phenological shifts within and between individuals. We found strong support for covariation in the timing of breeding arrival dates and the timing of the preceding moult. Breeding arrival dates were more repeatable at the individual level, as compared with the population level, even after accounting for individual traits (wean date as a pup, age and breeding experience) associated with phenological variability. Mother-daughter similarities in breeding phenology were also evident, indicating that additive genetic effects may contribute to between-individual variation in breeding phenology. Over 30 years, elephant seal phenology did not change towards earlier or later dates, and we found no correlation between annual fluctuations in phenology and indices of environmental variation. Our results show how maternal genetic (or non-genetic) effects, individual traits and linkages between cyclical life-history events can drive within- and between-individual variation in reproductive phenology.


Assuntos
Reprodução , Focas Verdadeiras , Animais , Feminino , Mudança Climática , Muda , Mães , Fenótipo , Reprodução/fisiologia
2.
Toxicol Ind Health ; 39(8): 421-440, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37271738

RESUMO

Cardiovascular diseases (CVD) are a common global cause of death and are therefore a major health concern. Inhaled or ingested environmental heavy metals contribute to the development of CVD. The aim of this study was to address the limited information available on the effect of relevant dosages of metals in mixtures. Three metals with reported effects on the cardiovascular system (CVS) were identified, and these metals were copper (Cu), manganese (Mn) and mercury (Hg). In Sprague-Dawley rats, the adverse effects of copper (Cu), manganese (Mn) and mercury (Hg), alone and as part of mixtures, on the blood parameters, the aorta and heart were investigated. Forty-eight male Sprague-Dawley rats were randomly divided into eight groups (n = 6): control, Cu, Mn, Hg, Cu + Mn, Cu + Hg, Mn + Hg and Cu, Mn + Hg. The seven experimental groups received the metal mixtures at 100 times the World Health Organisation (WHO) safety limit for drinking water (2 mg/L for Cu, 0.4 mg/L for Mn and 0.06 mg/L for Hg) via oral gavage for 28 days. After 28 days, compared with the control, red blood cell levels were increased for Cu + Hg. All other measured blood parameters were unchanged. Morphological changes in the tunica media were connective tissue deposition and an abundance of collagen type I in the metal exposed aortic tissues. In the cardiac tissue of metal-exposed rats, changes in the cardiomyocyte and myofibrillar arrangement, with an increase in collagen type I and III was observed. Ultrastructurally, the aortic collagen and elastin band arrangement and the cardiac mitochondrial and myofibrillar arrangement and structures were altered in the experimental groups. These changes indicated that exposure to these metals in rats caused minor changes in the blood parameters, however, the changes in tissue and cellular structure indicated an increased risk for the development of CVD.


Assuntos
Mercúrio , Metais Pesados , Masculino , Ratos , Animais , Manganês/toxicidade , Cobre/toxicidade , Mercúrio/toxicidade , Ratos Sprague-Dawley , Colágeno Tipo I , Aorta
3.
Mol Divers ; 21(4): 809-820, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28924942

RESUMO

Pelargonium sidoides DC (Geraniaceae) is a medicinal plant indigenous to Southern Africa that has been widely evaluated for its use in the treatment of upper respiratory tract infections. In recent studies, the anti-proliferative potential of P. sidoides was shown, and several phenolic compounds were identified as the bioactive compounds. Little, however, is known regarding their anti-proliferative protein targets. In this study, the anti-proliferative mechanisms of P. sidoides through in silico target identification and network pharmacology methodologies were evaluated. The protein targets of the 12 phenolic compounds were identified using the target identification server PharmMapper and the server for predicting Drug Repositioning and Adverse Reactions via the Chemical-Protein Interactome (DRAR-CPI). Protein-protein and protein-pathway interaction networks were subsequently constructed with Cytoscape 3.4.0 to evaluate potential mechanisms of action. A total of 142 potential human target proteins were identified with the in silico target identification servers, and 90 of these were found to be related to cancer. The protein interaction network was constructed from 86 proteins involved in 209 interactions with each other, and two protein clusters were observed. A pathway enrichment analysis identified over 80 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways enriched with the protein targets and included several pathways specifically related to cancer as well as various signaling pathways that have been found to be dysregulated in cancer. These results indicate that the anti-proliferative activity of P. sidoides may be multifactorial and arises from the collective regulation of several interconnected cell signaling pathways.


Assuntos
Antineoplásicos/farmacologia , Simulação por Computador , Pelargonium/química , Extratos Vegetais/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Terapia de Alvo Molecular , Extratos Vegetais/química , Mapeamento de Interação de Proteínas , Transdução de Sinais/efeitos dos fármacos
4.
J Evol Biol ; 29(9): 1667-79, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27012933

RESUMO

Understanding observed patterns of connectivity requires an understanding of the evolutionary processes that determine genetic structure among populations, with the most common models being associated with isolation by distance, allopatry or vicariance. Pinnipeds are annual breeders with the capacity for extensive range overlap during seasonal migrations, establishing the potential for the evolution of isolation by distance. Here, we assess the pattern of differentiation among six breeding colonies of the southern elephant seal, Mirounga leonina, based on mtDNA and 15 neutral microsatellite DNA markers, and consider measures of their demography and connectivity. We show that all breeding colonies are genetically divergent and that connectivity in this highly mobile pinniped is not strongly associated with geographic distance, but more likely linked to Holocene climate change and demographic processes. Estimates of divergence times between populations were all after the last glacial maximum, and there was evidence for directional migration in a clockwise pattern (with the prevailing current) around the Antarctic. We discuss the mechanisms by which climate change may have contributed to the contemporary genetic structure of southern elephant seal populations and the broader implications.


Assuntos
Mudança Climática , Genética Populacional , Focas Verdadeiras/genética , Animais , Regiões Antárticas , DNA Mitocondrial , Repetições de Microssatélites
5.
Plant Dis ; 100(12): 2383-2393, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30686164

RESUMO

Persimmon trees with dieback symptoms and cankers were observed in three production areas in Western Cape Province in South Africa. Isolations were made from diseased branches, cankers, and pruning wounds as well as fungal fruiting bodies on dead branches and old pruning wounds. Several trunk disease pathogens were identified based on morphological characteristics and by molecular methods, including Diaporthe eres, D. infecunda, Eutypella citricola, E. microtheca, Phaeoacremonium parasiticum, P. scolyti, P. australiense, P. minimum, Fomitiporia capensis, Fomitiporia sp., Fomitiporella sp., and Inocutis sp., which were isolated from persimmon for the first time in the world. Other first reports from persimmon in South Africa include D. foeniculina, D. ambigua, D. mutila, Diaporthe sp., Neofusicoccum australe, N. parvum, Diplodia seriata, and Eutypa lata. Pathogenicity tests conducted with all species, except the basidiomycetes, confirmed their status as possible persimmon pathogens. This is the first study to determine and identify fungi associated with diseased persimmon in South Africa. The knowledge gained in this study forms the basis for further research to determine the impact of these fungi on persimmon productivity.

6.
Mult Scler ; 21(7): 935-44, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25392318

RESUMO

BACKGROUND: Non-Gaussian diffusion imaging by using diffusional kurtosis imaging (DKI) allows assessment of isotropic tissue as of gray matter (GM), an important limitation of diffusion tensor imaging (DTI). OBJECTIVE: In this study, we describe DKI and DTI metrics of GM in multiple sclerosis (MS) patients and their association with cognitive deficits. METHODS: Thirty-four patients with relapsing-remitting MS and 17 controls underwent MRI on a 3T scanner including a sequence for DKI with 30 diffusion directions and 3b values for each direction. Mean kurtosis (MK), mean diffusivity and fractional anisotropy (FA) of cortical and subcortical GM were measured using histogram analysis. Spearman rank correlations were used to characterize associations among imaging measures and clinical/neuropsychological scores. RESULTS: In cortical GM, a significant decrease of MK (0.68 vs. 0.73; p < 0.001) and increase of FA (0.16 vs. 0.13; p < 0.001) was found in patients compared to controls. Decreased cortical MK was correlated with poor performance on the Delis-Kaplan Executive Function System test (r = 0.66, p = 0.01). CONCLUSION: Mean kurtosis is sensitive to abnormality in GM of MS patients and can provide information that is complementary to that of conventional DTI-derived metrics. The association between MK and cognitive deficits suggests that DKI might serve as a clinically relevant biomarker for cortical injury.


Assuntos
Encéfalo/patologia , Transtornos Cognitivos/etiologia , Imagem de Difusão por Ressonância Magnética/métodos , Substância Cinzenta/patologia , Esclerose Múltipla Recidivante-Remitente/patologia , Adulto , Transtornos Cognitivos/patologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/psicologia , Testes Neuropsicológicos , Adulto Jovem
7.
J Ethnopharmacol ; 309: 116377, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-36907477

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Tea (Camellia sinensis) has been consumed for centuries as traditional medicine for various diseases, including diabetes. The mechanism of action of many traditional medicines, including tea, often requires elucidation. Purple tea is a natural mutant of Camellia sinensis, grown in China and Kenya, and is rich in anthocyanins and ellagitannins. AIM OF THE STUDY: Here we aimed to determine whether commercial green and purple teas are a source of ellagitannins and whether green and purple teas, purple tea ellagitannins and their metabolites urolithins have antidiabetic activity. MATERIALS AND METHODS: Targeted UPLC-MS/MS was employed to quantify the ellagitannins corilagin, strictinin and tellimagrandin I, in commercial teas. The inhibitory effect of commercial green and purple teas and purple tea ellagitannins was evaluated on α-glucosidase and α-amylase. The bioavailable urolithins were then investigated for additional antidiabetic effects, by evaluating their effect on cellular glucose uptake and lipid accumulation. RESULTS: Corilagin, strictinin and tellimagrandin I (ellagitannins) were identified as potent inhibitors of α-amylase and α-glucosidase, with Ki values significantly lower (p < 0.05) than acarbose. Commercial green-purple teas were identified as ellagitannin sources, with especially high concentrations of corilagin. These commercial purple teas, containing ellagitannins, were identified as potent α-glucosidase inhibitors with IC50 values significantly lower (p < 0.05) than green teas and acarbose. Urolithin A and urolithin B were as effective (p> 0.05) as metformin in increasing glucose uptake in adipocytes, muscle cells and hepatocytes. In addition, similar (p > 0.05) to metformin, both urolithin A and urolithin B reduced lipid accumulation in adipocytes and hepatocytes. CONCLUSIONS: This study identified green-purple teas as an affordable widely available natural source with antidiabetic properties. Furthermore, additional antidiabetic effects of purple tea ellagitannins (corilagin, strictinin and tellimagrandin I) and urolithins were identified.


Assuntos
Taninos Hidrolisáveis , Hipoglicemiantes , Chá , Taninos Hidrolisáveis/análise , Taninos Hidrolisáveis/farmacologia , Hipoglicemiantes/farmacologia , Chá/química
8.
Physiol Meas ; 44(5)2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37072002

RESUMO

Objective. Appropriate adaptation of the maternal autonomic nervous system to progressing gestation is essential to a healthy pregnancy. This is partly evidenced by the association between pregnancy complications and autonomic dysfunction. Therefore, assessing maternal heart rate variability (HRV)-a proxy measure for autonomic activity-may offer insights into maternal health, potentially enabling the early detection of complications. However, identifying abnormal maternal HRV requires a thorough understanding of normal maternal HRV. While HRV in women of childbearing age has been extensively investigated, less is known concerning HRV during pregnancy. Subsequently, we investigate the differences in HRV between healthy pregnant women and their non-pregnant counterparts.Approach. We use a comprehensive suite of HRV features (assessing sympathetic and parasympathetic activity, heart rate (HR) complexity, HR fragmentation, and autonomic responsiveness) to quantify HRV in large groups of healthy pregnant (n= 258) and non-pregnant women (n= 252). We compare the statistical significance and effect size of the potential differences between the groups.Main results. We find significantly increased sympathetic and decreased parasympathetic activity during healthy pregnancy, along with significantly attenuated autonomic responsiveness, which we hypothesize serves as a protective mechanism against sympathetic overactivity. HRV differences between these groups typically had a large effect size (Cohen'sd> 0.8), with the largest effect accompanying the significantly reduced HR complexity and altered sympathovagal balance observed in pregnancy (Cohen'sd> 1.2).Significance. Healthy pregnant women are autonomically distinct from their non-pregnant counterparts. Subsequently, assumptions based on HRV research in non-pregnant women cannot be readily translated to pregnant women.


Assuntos
Sistema Nervoso Autônomo , Gravidez , Feminino , Humanos , Frequência Cardíaca/fisiologia
9.
Sci Rep ; 13(1): 21100, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-38036597

RESUMO

Due to the association between dysfunctional maternal autonomic regulation and pregnancy complications, tracking non-invasive features of autonomic regulation derived from wrist-worn photoplethysmography (PPG) measurements may allow for the early detection of deteriorations in maternal health. However, even though a plethora of these features-specifically, features describing heart rate variability (HRV) and the morphology of the PPG waveform (morphological features)-exist in the literature, it is unclear which of these may be valuable for tracking maternal health. As an initial step towards clarity, we compute comprehensive sets of HRV and morphological features from nighttime PPG measurements. From these, using logistic regression and stepwise forward feature elimination, we identify the features that best differentiate healthy pregnant women from non-pregnant women, since these likely capture physiological adaptations necessary for sustaining healthy pregnancy. Overall, morphological features were more valuable for discriminating between pregnant and non-pregnant women than HRV features (area under the receiver operating characteristics curve of 0.825 and 0.74, respectively), with the systolic pulse wave deterioration being the most valuable single feature, followed by mean heart rate (HR). Additionally, we stratified the analysis by sleep stages and found that using features calculated only from periods of deep sleep enhanced the differences between the two groups. In conclusion, we postulate that in addition to HRV features, morphological features may also be useful in tracking maternal health and suggest specific features to be included in future research concerning maternal health.


Assuntos
Fotopletismografia , Punho , Humanos , Feminino , Gravidez , Frequência Cardíaca/fisiologia , Articulação do Punho , Nível de Saúde , Eletrocardiografia
10.
Sci Rep ; 12(1): 19305, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369252

RESUMO

Pregnancy complications are associated with insufficient adaptation of the maternal autonomic nervous system to the physiological demands of pregnancy. Consequently, assessing maternal heart rate variability (mHRV)-which reflects autonomic regulation-is a promising tool for detecting early deterioration in maternal health. However, before mHRV can be used to screen for complications, an understanding of the factors influencing mHRV during healthy pregnancy is needed. In this retrospective observational study, we develop regression models to unravel the effects of maternal demographics (age, body mass index (BMI), gestational age (GA), and parity), cardiorespiratory factors (heart rate and breathing rate), and inter-subject variation on mHRV. We develop these models using two datasets which are comprised of, respectively, single measurements in 290 healthy pregnant women and repeated measurements (median = 8) in 29 women with healthy pregnancies. Our most consequential finding is that between one-third and two-thirds of the variation in mHRV can be attributed to inter-subject variability. Additionally, median heart rate dominantly affects mHRV (p < 0.001), while BMI and parity have no effect. Moreover, we found that median breathing rate, age, and GA all impact mHRV (p < 0.05). These results suggest that personalized, long-term monitoring would be necessary for using mHRV for obstetric screening.


Assuntos
Frequência Cardíaca , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Idade Gestacional , Paridade , Demografia
11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 4982-4986, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36085954

RESUMO

Autonomic regulation is essential in enabling a healthy pregnancy. In fact, several pregnancy complications are associated with autonomic dysfunction. Better understanding of the maternal autonomic state during healthy pregnancy may aid in the early detection of such complications. One aspect of autonomic regulation is autonomic responsiveness, which can by assessed by phase rectified signal averaging (PRSA). While other areas of research have found blunted physiological responses in pregnancy, this paper presents the first investigation of maternal autonomic responsiveness as assessed by PRSA. We find significantly reduced rates of responses, as well as an attenuated capacity for heart rate acceleration when comparing pregnant women to non-pregnant controls. We hypothesize that this attenuated autonomic control may serve to protect the mother against her imbalanced autonomic state, as increased sympathetic and decreased parasympathetic modulation accompany healthy pregnancies. Clinical Relevance- Maternal autonomic responsiveness is attenuated in pregnancy in comparison to non-pregnant women. Understanding maternal autonomic state not only improves our knowledge of gestational physiology but also forms the basis for the early detection of pregnancy complications associated with maternal autonomic dysfunction.


Assuntos
Doenças do Sistema Nervoso Autônomo , Complicações na Gravidez , Sistema Nervoso Autônomo/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Gravidez
12.
AJNR Am J Neuroradiol ; 41(7): 1232-1237, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32586965

RESUMO

BACKGROUND AND PURPOSE: The Woven EndoBridge (WEB) device is an established technique for the treatment of intracranial aneurysms. Occasionally, persistent opacification inside the WEB lumen can be observed at follow-up (previously described as Bicêtre Occlusion Scale Score 1). We evaluated potential risk factors of this phenomenon, hypothesizing that initial deviation of the WEB device from the aneurysm axis, size of the aneurysmal neck surface, or inappropriate WEB sizing correlates with Bicêtre Occlusion Scale Score 1 findings. MATERIALS AND METHODS: We systematically reviewed all patients treated with the WEB device between February 2014 and December 2018 in our neurointerventional center. Patients with midterm follow-up DSA available were considered for aneurysm evaluation applying the Bicêtre Occlusion Scale Score. WEB angle deviation from the aneurysm axis, neck widths, and WEB sizes were collected. RESULTS: We included 65 patients with 67 intracranial aneurysms. Eleven of 67 (16.4%) intracranial aneurysms showed the Bicêtre Occlusion Scale Score 1 phenomenon at follow-up. Anterior-posterior projections of WEB axis deviation (angles measured in degrees) were significantly different between the Bicêtre Occlusion Scale Score 1 cohort (median ± interquartile range, 17 ± 17) and all other Bicêtre Occlusion Scale Scores (median ± interquartile range, 7 ± 11; P = .023), whereas in lateral projections, no significant difference was observed (median ± interquartile range, 10 ± 10 versus 8 ± 9; P = .169). Neck or aneurysm recurrence, but not the Bicêtre Occlusion Scale Score 1 phenomenon, occurred significantly more often in patients with inappropriate WEB sizing compared with appropriate WEB sizing (median ± interquartile range, 1 ± 1.3 versus 0 ± 0; P < .001/P = .664). CONCLUSIONS: The Bicêtre Occlusion Scale Score 1 phenomenon is associated with an initial deviation of the WEB device from the aneurysm axis but does not correlate with aneurysmal neck surface measurements or WEB sizing.


Assuntos
Prótese Vascular , Aneurisma Intracraniano/terapia , Adulto , Idoso , Progressão da Doença , Embolização Terapêutica/instrumentação , Embolização Terapêutica/métodos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
13.
Food Res Int ; 137: 109720, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33233289

RESUMO

Solanum nigrum complex (Black nightshade) is a wild leafy vegetable with phenolic antioxidant compounds related to the reduction of oxidative stress. Changes in phenolics and bioactivity due to cooking and gastrointestinal digestion of black nightshade were compared to spinach. Predominant compounds of black nightshade were myricetin, quercetin-3-O-robinoside, 3,4-dicaffeoylquinic acid, 3-caffeoylquinic acid, and rutin, which were improved after boiling but reduced after in vitro digestion. Phenolics were reduced after digestion of black nightshade and spinach; however, bioactivity was still retained, especially in preventing oxidative stress in Caco-2 cells. Hence, indicating their potential to reduce oxidative stress related diseases of the digestive tract.


Assuntos
Solanum nigrum , Antioxidantes , Células CACO-2 , Digestão , Humanos , Fenóis
14.
Food Chem ; 311: 126023, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31864189

RESUMO

The effects of boiling and in vitro human simulated digestion on phenolic compounds and bioactivity of the African leafy green vegetable, Bidens pilosa, known as Blackjack in South Africa, was investigated and compared to the leafy green vegetable Spinacia oleracea (Spinach). Metabolites such as 3-caffeoylquinic acid, catechin, 4-caffeoylquinic acid, quercetin-3-O-robinobioside, rutin and quercetin-3-O-glucoside were dominant in the boiled methanolic compared with the raw methanolic extracts of the Blackjack. The total phenolic and flavonoid content generally decreased after in vitro complete digestion for both raw and boiled extracts, indicating that pH and environment associated with digestion alters the bioactivity of the extracted phenolics. Both leafy green vegetables had beneficial effects, but all Blackjack extracts were more effective in preventing the AAPH-mediated oxidation of Caco-2 cells, low-density lipoprotein and deoxyribonucleic acid than those of the spinach. This study identified the health benefits of eating Blackjack and therefore, the cultivation and consumption of this leafy green vegetable should be promoted.


Assuntos
Antioxidantes/metabolismo , Bidens/química , Flavonoides/análise , Fenóis/análise , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Células CACO-2 , Culinária , DNA/efeitos adversos , Digestão , Flavonoides/metabolismo , Flavonoides/farmacologia , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Benefícios do Seguro , Lipoproteínas LDL/efeitos adversos , Metanol , Oxirredução/efeitos dos fármacos , Fenóis/metabolismo , Fenóis/farmacologia , Folhas de Planta/química , Spinacia oleracea/química , Verduras/química
15.
Hum Exp Toxicol ; 38(4): 419-433, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30537864

RESUMO

Water contamination with metals due to anthropogenic activity is increasing and subsequent exposure increases the risk of associated toxicity. Exposure is not limited to a single metal but usually involves mixtures of different metals at different concentrations. Little is known about the contribution of this type of exposure, in humans, to the development of non-communicable diseases such as cardiovascular disease, and an increased risk to thrombosis. The World Health Organization has established limits for metal levels in drinking water and this includes levels for copper (Cu), manganese (Mn) and mercury (Hg). In this study, at 100X these limits, the ability of the metals' oxidative effects as catalysts of the Fenton reaction and/or ability to bind glutathione (GSH) were determined. The haemostatic effects of these metals, alone and in combination, at the World Health Organization limit were then evaluated. The ultrastructural and viscoelastic alterations of exposed ex vivo whole blood were also evaluated using scanning electron microscopy and thromboelastography® (TEG), respectively. Cu, alone and in combination with Mn and/or Hg, induced hydroxyl radical formation and reduced GSH levels. Ex vivo exposure caused deformation of erythrocytes and accelerated platelet activation especially for Cu, alone and in combination, with Mn. Reduction in the lysis potential of the clot was also observed for all combinations, especially Cu in combination with Hg as well as Mn alone. Although the TEG findings were not statistically significant, the trends indicate that the exposure to these metals, alone and in combination, adversely affects thrombus formation in ex vivo blood, thereby potentially increasing the risk in exposed individuals for thrombosis.


Assuntos
Cobre/toxicidade , Hemostáticos/toxicidade , Manganês/toxicidade , Mercúrio/toxicidade , Poluentes Químicos da Água/toxicidade , Plaquetas/efeitos dos fármacos , Plaquetas/fisiologia , Interações Medicamentosas , Eritrócitos/efeitos dos fármacos , Eritrócitos/fisiologia , Glutationa/metabolismo , Humanos , Radical Hidroxila/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Tromboelastografia
16.
Neuroradiology ; 50(7): 549-57, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18458896

RESUMO

INTRODUCTION: Optic neuritis (ON) and any other early manifestation of multiple sclerosis (MS) are referred to as clinically isolated syndrome (CIS) as long as MS is suspected. In this prospective study we aimed to determine whether diffusion tensor imaging (DTI) could quantify structural changes in patients with early MS. METHODS: A total of 24 patients and 15 control subjects were prospectively followed by clinical examinations and MRI. the main inclusion criterion was presentation with ON. Patients underwent serial MRI scans: MRI1 (baseline, n=24), MRI2 (mean 6.6 months, n=24), MRI3 (mean 13.0 months, n=14), MRI4 (mean 39.4 months, n=5). Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) maps were derived from DTI. Four regions of interest (ROIs) were defined in normal-appearing white matter (NAWM). RESULTS: In the temporal course FA decreased in the genu of the callosal body (GCC) from MRI1 to MRI4 (P=0.005) and in the splenium of the callosal body (SCC) (P=0.006). Patients already had lower FA values in the SCC (P<0.01) on MRI1 compared with the controls. Patients had lower FA values in the GCC (P<0.01) starting from MRI2. Patients with definite MS on follow-up (n=9) showed a correlation between FA in the SCC and time (r=-0.40, P=0.004), whereas patients without progression did not. CONCLUSIONS: Our findings suggest that the corpus callosum is an early site for development of anisotropy changes in MS patients with ON. There seems to be a primary FA decrease in all patients with ON that only deteriorates in the group developing definite MS.


Assuntos
Corpo Caloso/patologia , Imagem de Difusão por Ressonância Magnética , Imagem Ecoplanar , Esclerose Múltipla/patologia , Neurite Óptica/patologia , Adulto , Anisotropia , Estudos de Coortes , Diagnóstico Precoce , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Neurite Óptica/etiologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Adulto Jovem
17.
J S Afr Vet Assoc ; 79(1): 25-30, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18678188

RESUMO

Captive and wild African elephants frequently suffer tusk fractures. Several institutions shorten the tusks of captive elephants to reduce fractures and injury as a result of behaviour within enclosures. Fracturing or coronal amputations that expose pulp lead to pain for the elephant. Estimating coronal pulp lengths may thus help to minimise the risk of pulp exposure during amputations. We aimed to determine the length of the pulp beyond the lip margin from an external tusk characteristic. Tusks collected from elephants in Namibia and the Kruger National Park had similar morphological relationships. This statistical property allowed us to correct for missing data in our data sets. Pulp volume and pulp length correlated with tusk circumference at the lip. Even so, the circumference at the lip could not predict the length of the pulp in the crown external to the lip. Our findings suggest that tusks, irrespective of sex or age, amputated further than 300 mm from the lip should not expose pulp.


Assuntos
Polpa Dentária/anatomia & histologia , Polpa Dentária/inervação , Elefantes , Fraturas dos Dentes/veterinária , Dente/anatomia & histologia , Fatores Etários , Animais , Animais Selvagens , Animais de Zoológico , Elefantes/anatomia & histologia , Feminino , Masculino , Fatores Sexuais , Dente/inervação , Fraturas dos Dentes/epidemiologia , Fraturas dos Dentes/prevenção & controle
18.
J Comp Pathol ; 158: 77-89, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29422320

RESUMO

Descriptions of several oral, maxillofacial and dental conditions/diseases exist for a variety of captive large felids, but little is reported on the pathology of free roaming large felids. Apart from focal palatine erosions (FPEs) as initially described by Fitch and Fagan (1982) and some reference to absent incisor teeth, few data exist on diseases affecting the oral, maxillofacial and dental structures of cheetahs (Acinonyx jubatus), regardless of their captivity status. This study reports 18 different conditions affecting the teeth, bone and oral cavity soft tissue of cheetahs, based on initial assessment of 256 animals over 11 years (2002-2012) in South Africa and Namibia. This report excludes oral tumours or FPEs, but includes several acquired and developmental conditions never described before.


Assuntos
Doenças Estomatognáticas/veterinária , Acinonyx , Animais , Animais de Zoológico
19.
R Soc Open Sci ; 5(10): 181227, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30473858

RESUMO

Evaluating how populations are connected by migration is important for understanding species resilience because gene flow can facilitate recovery from demographic declines. We therefore investigated the extent to which migration may have contributed to the global recovery of the Antarctic fur seal (Arctocephalus gazella), a circumpolar distributed marine mammal that was brought to the brink of extinction by the sealing industry in the eighteenth and nineteenth centuries. It is widely believed that animals emigrating from South Georgia, where a relict population escaped sealing, contributed to the re-establishment of formerly occupied breeding colonies across the geographical range of the species. To investigate this, we interrogated a genetic polymorphism (S291F) in the melanocortin 1 receptor gene, which is responsible for a cream-coloured phenotype that is relatively abundant at South Georgia and which appears to have recently spread to localities as far afield as Marion Island in the sub-Antarctic Indian Ocean. By sequencing a short region of this gene in 1492 pups from eight breeding colonies, we showed that S291F frequency rapidly declines with increasing geographical distance from South Georgia, consistent with locally restricted gene flow from South Georgia mainly to the South Shetland Islands and Bouvetøya. The S291F allele was not detected farther afield, suggesting that although emigrants from South Georgia may have been locally important, they are unlikely to have played a major role in the recovery of geographically more distant populations.

20.
Space Sci Rev ; 2142018.
Artigo em Inglês | MEDLINE | ID: mdl-33758433

RESUMO

The Ionospheric Connection Explorer, or ICON, is a new NASA Explorer mission that will explore the boundary between Earth and space to understand the physical connection between our world and our space environment. This connection is made in the ionosphere, which has long been known to exhibit variability associated with the sun and solar wind. However, it has been recognized in the 21st century that equally significant changes in ionospheric conditions are apparently associated with energy and momentum propagating upward from our own atmosphere. ICON's goal is to weigh the competing impacts of these two drivers as they influence our space environment. Here we describe the specific science objectives that address this goal, as well as the means by which they will be achieved. The instruments selected, the overall performance requirements of the science payload and the operational requirements are also described. ICON's development began in 2013 and the mission is on track for launch in 2017. ICON is developed and managed by the Space Sciences Laboratory at the University of California, Berkeley, with key contributions from several partner institutions.

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