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1.
Am J Physiol Regul Integr Comp Physiol ; 324(2): R171-R182, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36503254

RESUMO

A high-fat (HF) diet causes fatty liver, hyperlipidemia, and hypercholesterolemia, and cottonseed oil (CSO) has been shown to improve liver and plasma lipids in human and mouse models. The purpose of this study was to determine the effect of CSO vs. olive oil (OO)-enriched diets on lipid levels in a HF-diet model of fatty liver disease. We placed mice on a HF diet to induce obesity and fatty liver, after which mice were placed on CSO or OO diets, with chow and HF (5.1 kcal/g) groups as control. When CSO- and OO-fed mice were given isocaloric diets with the HF group, there were no differences in body weight, plasma, or hepatic lipids. However, when the CSO and OO diets were reduced in calories (4.0 kcal/g), CSO and OO groups reduced body weight. The CSO group had lower plasma total cholesterol (-56 ± 6%, P < 0.01), free cholesterol (-53 ± 7%, P < 0.01), triglycerides (-61 ± 14%, P < 0.01), and LDL (-42 ± 16%, P = 0.01) vs. HF group whereas the OO diet lowered LDL (-18 ± 12%, P = 0.05) vs. HF. Furthermore, the CSO diet decreased hepatic total cholesterol (-40 ± 12%, P < 0.01), free cholesterol (-23 ± 11%, P = 0.04), and triglycerides (-47 ± 12%, P = 0.02). There were no significant changes in lipogenesis and fatty acid oxidation among the groups. However, the CSO group increased lipid oxidative gene expression in liver and dihydrosterculic acid increased PPARα target genes with in vitro models. Taken together, consuming a reduced calorie diet enriched in CSO reduces liver and plasma lipid profiles in an obese model of fatty liver.


Assuntos
Óleo de Sementes de Algodão , Hepatopatia Gordurosa não Alcoólica , Animais , Masculino , Camundongos , Peso Corporal , Colesterol , Óleo de Sementes de Algodão/metabolismo , Óleo de Sementes de Algodão/farmacologia , Dieta Hiperlipídica , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Azeite de Oliva/farmacologia , Azeite de Oliva/metabolismo , Triglicerídeos
2.
VideoGIE ; 7(10): 348-349, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36238803

RESUMO

Video 1Description of the technique of EUS-guided liver biopsy using a modified wet heparin suction technique.

3.
Ecology ; 103(8): e3718, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35405019

RESUMO

Monitoring technologies now provide real-time animal location information, which opens up the possibility of developing forecasting systems to fuse these data with movement models to predict future trajectories. State-space modeling approaches are well established for retrospective location estimation and behavioral inference through state and parameter estimation. Here we use a state-space model within a comprehensive data assimilative framework for probabilistic animal movement forecasting. Real-time location information is combined with stochastic movement model predictions to provide forecasts of future animal locations and trajectories, as well as estimates of key behavioral parameters. Implementation uses ensemble-based sequential Monte Carlo methods (a particle filter). We first apply the framework to an idealized case using a nondimensional animal movement model based on a continuous-time random walk process. A set of numerical forecasting experiments demonstrates the workflow and key features, such as the online estimation of behavioral parameters using state augmentation, the use of potential functions for habitat preference, and the role of observation error and sampling frequency on forecast skill. For a realistic demonstration, we adapt the framework to short-term forecasting of the endangered southern resident killer whale (SRKW) in the Salish Sea using visual sighting information wherein the potential function reflects historical habitat utilization of SRKW. We successfully estimate whale locations up to 2.5 h in advance with a moderate prediction error (<5 km), providing reasonable lead-in time to mitigate vessel-whale interactions. It is argued that this forecasting framework can be used to synthesize diverse data types and improve animal movement models and behavioral understanding and has the potential to lead to important advances in movement ecology.


Assuntos
Ecologia , Ecossistema , Animais , Previsões , Estudos Retrospectivos
4.
Plant Biotechnol J ; 19(6): 1268-1282, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33492748

RESUMO

Upland cotton (Gossypium hirsutum L.) is an economically important multi-purpose crop cultivated globally for fibre, seed oil and protein. Cottonseed oil also is naturally rich in vitamin E components (collectively known as tocochromanols), with α- and γ-tocopherols comprising nearly all of the vitamin E components. By contrast, cottonseeds have little or no tocotrienols, tocochromanols with a wide range of health benefits. Here, we generated transgenic cotton lines expressing the barley (Hordeum vulgare) homogentisate geranylgeranyl transferase coding sequence under the control of the Brassica napus seed-specific promoter, napin. Transgenic cottonseeds had ~twofold to threefold increases in the accumulation of total vitamin E (tocopherols + tocotrienols), with more than 60% γ-tocotrienol. Matrix assisted laser desorption ionization-mass spectrometry imaging showed that γ-tocotrienol was localized throughout the transgenic embryos. In contrast, the native tocopherols were distributed unequally in both transgenic and non-transgenic embryos. α- Tocopherol was restricted mostly to cotyledon tissues and γ-tocopherol was more enriched in the embryonic axis tissues. Production of tocotrienols in cotton embryos had no negative impact on plant performance or yield of other important seed constituents including fibre, oil and protein. Advanced generations of two transgenic events were field grown, and extracts of transgenic seeds showed increased antioxidant activity relative to extracts from non-transgenic seeds. Furthermore, refined cottonseed oil from the two transgenic events showed 30% improvement in oxidative stability relative to the non-transgenic cottonseed oil. Taken together, these materials may provide new opportunities for cottonseed co-products with enhanced vitamin E profile for improved shelf life and nutrition.


Assuntos
Gossypium , Tocotrienóis , Suplementos Nutricionais , Gossypium/genética , Estresse Oxidativo , Sementes , Tocoferóis
5.
Nutr Res ; 45: 52-62, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29037332

RESUMO

Polyunsaturated fatty acid (PUFA)-rich diets are thought to provide beneficial effects toward metabolic health in part through their bioactive properties. We hypothesized that increasing PUFA intake in mice would increase peroxisome proliferator activated receptor delta (PPARδ) expression and activity, and we sought to examine the effect of different PUFA-enriched oils on muscle PPARδ expression. One of the oils we tested was cottonseed oil (CSO) which is primarily linoleic acid (53%) and palmitic acid (24%). Mice fed a CSO-enriched diet (50% energy from fat) displayed no change in muscle PPARδ expression; however, in the liver, it was consistently elevated along with its transcriptional coactivator Pgc-1. Male mice were fed chow or CSO-, saturated fat (SFA)-, or linoleic acid (18:2)-enriched diets that were matched for macronutrient content for 4 weeks. There were no differences in food intake, body weight, fasting glucose, glucose tolerance, or energy expenditure between chow- and CSO-fed mice, whereas SFA-fed mice had increased fat mass and 18:2-fed mice were less glucose tolerant. Metabolomic analyses revealed that the livers of CSO-fed mice closely matched those of chow-fed but significantly differed from SFA- and 18:2-enriched groups. Fatty acid composition of the diets and livers revealed an impairment in desaturase activity and the presence of dihydrosterculic acid (DHSA) in the CSO-fed mice. The effect of DHSA on PPARδ and stearoyl-CoA desaturase-1 expression mimicked that of the CSO-fed mice. Taken together, these data suggest that DHSA from CSO may be an effective means to increase PPARδ expression with concomitant suppression of liver stearoyl-CoA desaturase-1 activity.


Assuntos
Óleo de Sementes de Algodão/química , Dieta Hiperlipídica , Ácidos Graxos/farmacologia , Fígado/metabolismo , PPAR delta/análise , Estearoil-CoA Dessaturase/antagonistas & inibidores , Animais , Metabolismo Energético , Ácidos Graxos/análise , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/química , Masculino , Metabolômica , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/química
6.
J Food Prot ; 80(8): 1228-1238, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28686496

RESUMO

Polychlorinated biphenyls (PCBs; sum of 36 congeners) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs; sum of 17 2,3,7,8-substituted congeners) were measured in 93 composite samples prepared from individual lake trout (Salvelinus namaycush) and whitefish (Coregonus clupeaformis) samples collected from Lake Erie, Lake Huron, and Lake Superior. All samples had detectable concentrations of PCBs and PCDD/Fs; maximum PCB concentrations in both trout (750 ng g-1 whole weight [ww]) and whitefish (210 ng g-1 ww) were found in composites from fish collected from Lake Huron. The maximum toxic equivalent concentration was found in a lake trout composite sample from Lake Huron (53 pg g-1 ww). PCB and PCDD/F congener profiles were comparable to patterns observed in fishes collected from other regions of Canada, although concentrations were above those found in other regions. A positive correlation was found between PCB concentrations determined using the historical Aroclor equivalency method and those determined using the sum of the congeners measured (r2 = 0.871; Spearman correlation r = 0.917) or using the six indicator PCB congeners (28, 52, 101, 138, 153, and 180; r2 = 0.850; Spearman correlation r = 0.935). PCBs were the dominant contributor to the overall toxic equivalent concentrations in the fish composite samples tested. These findings provide insight into PCB and PCDD/F concentrations in two commercially important fish species over a discrete time period.


Assuntos
Dioxinas/isolamento & purificação , Contaminação de Alimentos/análise , Bifenilos Policlorados/isolamento & purificação , Salmonidae/metabolismo , Truta/metabolismo , Animais , Canadá , Pesqueiros , Furanos , Lagos
7.
Nat Commun ; 8: 15325, 2017 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-28524851

RESUMO

Rebuilding depleted fish stocks is an international policy goal and a 2020 Aichi target under the Convention on Biological Diversity. However, stock productivity may shift with future climate change, with unknown consequences for sustainable harvesting, biomass targets and recovery timelines. Here we develop a stochastic modelling framework to characterize variability in the intrinsic productivity parameter (r) and carrying capacity (K) for 276 global fish stocks worldwide. We use models of dynamic stock productivity fitted via Bayesian inference to forecast rebuilding timelines for depleted stocks. In scenarios without fishing, recovery probabilities are reduced by 19%, on average, relative to models assuming static productivity. Fishing at 90% of the maximum sustainable rate depresses recovery probabilities by 42%, on average, relative to static models. This work reveals how a changing environmental context can delay the rebuilding of depleted fish stocks, and provides a framework to account for the potential impacts of environmental change on the productivity of wildlife populations more broadly.


Assuntos
Biomassa , Pesqueiros , Peixes/fisiologia , Animais , Teorema de Bayes , Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais , Meio Ambiente , Dinâmica Populacional , Probabilidade , Processos Estocásticos , Fatores de Tempo
8.
Planta ; 245(3): 611-622, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27988886

RESUMO

MAIN CONCLUSION: Some naturally occurring cotton accessions contain commercially attractive seed oil fatty acid profiles. The likely causal factor for a high-oleate trait in pima cotton ( Gossypium barbadense ) accession GB-713 is described here. Vegetable oils are broadly used in the manufacture of many human and animal nutritional products, and in various industrial applications. Along with other well-known edible plant oils from soybean, corn, and canola, cottonseed oil is a valuable commodity. Cottonseed oil is a co-product derived from the processing of cottonseed fiber. In the past, it was used extensively in a variety of food applications. However, cottonseed oil has lost market share in recent years due to less than optimal ratios of the constituent fatty acids found in either traditional or partially hydrogenated oil. Increased awareness of the negative health consequences of dietary trans-fats, along with the public wariness associated with genetically modified organisms has created high demand for naturally occurring oil with high monounsaturate/polyunsaturate ratios. Here, we report the discovery of multiple exotic accessions of pima cotton that contain elevated seed oil oleate content. The genome of one such accession was sequenced, and a mutant candidate fatty acid desaturase-2 (FAD2-1D) gene was identified. The mutant protein produced significantly less linoleic acid in infiltrated Arabidopsis leaf assays, compared to a repaired version of the same enzyme. Identification of this gene provides a valuable resource. Development of markers associated with this mutant locus will be very useful in efforts to breed the high-oleate trait into agronomic fiber accessions of upland cotton.


Assuntos
Alelos , Óleo de Sementes de Algodão/química , Ácidos Graxos Dessaturases/genética , Gossypium/enzimologia , Mutação/genética , Ácido Oleico/metabolismo , Sequência de Aminoácidos , Cromatografia Gasosa , Ácidos Graxos Dessaturases/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Gossypium/genética , Ácido Linoleico/análise , Filogenia , Estabilidade de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA
10.
Phytochemistry ; 122: 165-171, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26725485

RESUMO

The report that the cotton leaf perforator, Bucculatrix thurberiella, is one of the few insect herbivores to attack Gossypium thurberi prompted an investigation of the terpenoids present in the leaves of this wild species of cotton. Members of Gossypium produce subepidermal pigment glands in their leaves that contain the dimeric sesquiterpenoid gossypol as well as other biosynthetically related terpenoids. In addition to gossypol, a previously unknown dimeric sesquiterpenoid, gossypolhemiquinone (GHQ), was identified in trace amounts in G. thurberi, a member of the D genome. Other members of the D genome of Gossypium were subsequently found to contain this compound, but GHQ was not detected in commercial cotton cultivars. When fed to Helicoverpa zea in an artificial diet, GHQ delayed days-to-pupation, reduced pupal weights, and survival to adulthood to a lesser or equal extent than gossypol in comparison to the control diet. However, GHQ had a synergistic effect on survival and days-to-pupation when combined with gossypol at the highest dosage tested (0.18%; 15.5:84.5 GHQ:gossypol). Because gossypol exhibits anti-cancer activity, GHQ was also evaluated for its anti-cancer activity against the National Cancer Institute's 60-Human Tumor Cell Line Screen. Significant inhibitory activity against most of these cell lines was not observed, but the results may offer some promise against leukemia cancer cell lines.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Gossypium/química , Gossipol/análogos & derivados , Gossipol/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Gossypium/genética , Gossipol/química , Gossipol/farmacologia , Larva/efeitos dos fármacos , Estrutura Molecular , Mariposas/efeitos dos fármacos , Folhas de Planta/metabolismo
11.
Proc Natl Acad Sci U S A ; 113(1): 134-9, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26668368

RESUMO

Marine fish and invertebrates are shifting their regional and global distributions in response to climate change, but it is unclear whether their productivity is being affected as well. Here we tested for time-varying trends in biological productivity parameters across 262 fish stocks of 127 species in 39 large marine ecosystems and high-seas areas (hereafter LMEs). This global meta-analysis revealed widespread changes in the relationship between spawning stock size and the production of juvenile offspring (recruitment), suggesting fundamental biological change in fish stock productivity at early life stages. Across regions, we estimate that average recruitment capacity has declined at a rate approximately equal to 3% of the historical maximum per decade. However, we observed large variability among stocks and regions; for example, highly negative trends in the North Atlantic contrast with more neutral patterns in the North Pacific. The extent of biological change in each LME was significantly related to observed changes in phytoplankton chlorophyll concentration and the intensity of historical overfishing in that ecosystem. We conclude that both environmental changes and chronic overfishing have already affected the productive capacity of many stocks at the recruitment stage of the life cycle. These results provide a baseline for ecosystem-based fisheries management and may help adjust expectations for future food production from the oceans.


Assuntos
Mudança Climática , Pesqueiros/métodos , Peixes/crescimento & desenvolvimento , Animais , Biomassa , Clorofila/metabolismo , Estágios do Ciclo de Vida , Oceanos e Mares , Fitoplâncton/crescimento & desenvolvimento , Fitoplâncton/metabolismo , Dinâmica Populacional
12.
J Vasc Interv Radiol ; 26(10): 1501-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26239895

RESUMO

PURPOSE: To report preliminary clinical experience with a new symmetric-tip dialysis catheter compared with a conventional split-tip catheter. MATERIALS AND METHODS: Over a 5-month period, patients requiring a tunneled catheter for hemodialysis or undergoing exchange of a dysfunctional dialysis catheter at a tertiary academic medical center were retrospectively analyzed. Patients underwent placement of a VectorFlow or Ash Split Cath catheter at the discretion of the inserting interventional radiologist. Patient demographics, catheter patency, mean blood flow rate, and arterial and venous pressures were compared according to catheter type. Catheter failure was analyzed based on clinical and anatomic variables by using a multivariate Cox proportional-hazards model. RESULTS: A total of 33 VectorFlow and 46 Ash Split Cath catheters were placed. Patients in the VectorFlow group had significantly higher body mass index (P = .013) and Charlson Comorbidity Index (P = .049), as well as more non-internal jugular vein placements. At 120 days, 89% of VectorFlow catheters remained functional, compared with 45% of Ash Split Cath catheters (P = .046). The VectorFlow catheter was associated with 16% lower arterial pressures during dialysis (P = .009); mean blood flow rate was equivalent. On multivariate analysis, the risk of catheter failure was 13.3 times higher in the Ash Split Cath group compared with the VectorFlow group (P = .004). Left-sided catheters were also predictive of catheter failure (relative risk = 5.5; P = .02). CONCLUSIONS: The VectorFlow catheter was associated with a significant increase in intervention-free catheter patency compared with the Ash Split Cath catheter, with equivalent flow at lower arterial pressures during dialysis.


Assuntos
Cateterismo Venoso Central/instrumentação , Cateteres de Demora , Cateteres Venosos Centrais , Veias Jugulares/fisiopatologia , Diálise Renal/instrumentação , Velocidade do Fluxo Sanguíneo , Cateterismo Venoso Central/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Diálise Renal/métodos , Resultado do Tratamento
13.
Ecol Lett ; 17(12): 1518-25, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25224645

RESUMO

Fisheries exploitation has caused widespread declines in marine predators. Theory predicts that predator depletion will destabilise lower trophic levels, making natural communities more vulnerable to environmental perturbations. However, empirical evidence has been limited. Using a community matrix model, we empirically assessed trends in the stability of a multispecies coastal fish community over the course of predator depletion. Three indices of community stability (resistance, resilience and reactivity) revealed significantly decreasing stability concurrent with declining predator abundance. The trophically downgraded community exhibited weaker top-down control, leading to predator-release processes in lower trophic levels and increased susceptibility to perturbation. At the community level, our results suggest that high predator abundance acts as a stabilising force to the naturally stochastic and highly autocorrelated dynamics in low trophic species. These findings have important implications for the conservation and management of predators in marine ecosystems and provide empirical support for the theory of predatory control.


Assuntos
Peixes , Cadeia Alimentar , Animais , Itália , Mar Mediterrâneo , Modelos Estatísticos , Comportamento Predatório
14.
Ecol Appl ; 24(4): 862-76, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24988782

RESUMO

This study undertakes ecological analysis focused on predictive modelling and design for spatial sampling. The approaches are applied to a set of coastal marine benthic macrofaunal observations, and associated environmental data, measured at 48 sites in St Anns Bay, Nova Scotia, Canada. A multivariate generalized least-squares regression was used to establish a predictive relationship between benthic fauna and the environment. Five ecological indices derived from faunal composition (abundance, richness, species number, diversity, AMBI) were treated as a multivariate response, and 10 environmental variables as candidate predictors. The multivariate regression also incorporated the effects of spatial autocorrelation. Predictive relationships were highly significant, and variable selection identified three key environmental predictors (median sediment grain size, porosity, and sulfide). Using these baseline data, we developed a procedure to identify a reduced sampling design for long-term monitoring of benthic faunal health. The procedure is based on a sequential (backward elimination) algorithm to identify the set of sites that contributed most to the overall information. This study provides a general and comprehensive statistical framework for treating environmental monitoring and sampling design. It can be extended beyond the statistical framework used, and applied to a range of ecological applications.


Assuntos
Monitoramento Ambiental/métodos , Modelos Biológicos , Oceanos e Mares , Animais , Demografia , Nova Escócia
15.
Hand Surg ; 19(1): 85-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24641746

RESUMO

Proximal interphalangeal joint (PIPJ) fractures are a treatment challenge for hand surgeons. Poor treatment options may lead to stiffness, non-union and markedly reduced range of movement (ROM). We describe our experience using the Hoffman-2 micro static external fixation device (Stryker) in a case series of ten patients with closed comminuted intra-articular PIPJ fractures. The use of this device in the management of these fractures has not previously been described. The mean total active motion (TAM) of the injured joint had recovered to 80% of normal at the six-month follow up.


Assuntos
Traumatismos dos Dedos/cirurgia , Articulações dos Dedos , Fixação de Fratura/métodos , Fraturas Cominutivas/cirurgia , Fraturas Intra-Articulares/cirurgia , Adulto , Feminino , Articulações dos Dedos/diagnóstico por imagem , Articulações dos Dedos/cirurgia , Fraturas Cominutivas/diagnóstico por imagem , Humanos , Fraturas Intra-Articulares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia , Amplitude de Movimento Articular , Adulto Jovem
16.
Cardiovasc Intervent Radiol ; 37(6): 1540-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24352863

RESUMO

PURPOSE: Transjugular liver biopsy (TJLB) is commonly performed for staging of liver fibrosis and cirrhosis among patients with coagulopathy and/or ascites. We hypothesized that device orientation during needle firing influences hepatic tissue apposition with the specimen notch and specimen quality. METHODS: Needle biopsies were performed in ex vivo bovine livers with specimen notch of the biopsy device oriented at cranial, caudal, or lateral directions with respect to the guiding metal cannula. Biopsy specimen length was measured and evaluated for fragmentation using light microscopy. In addition, a consecutive cohort of patients (n = 50) who underwent TJLB with random (n = 22) or caudal (n = 28) needle orientation was retrospectively reviewed. The number of needle passes was documented, and pathology specimen adequacy was graded using an ordinal scale. RESULTS: A total of 400 biopsies were performed (100 in each orientation) in ex vivo bovine livers. Longer specimens were obtained with caudal orientation of the needle specimen notch (p < 0.0001, ANOVA and Kruskal-Wallis tests). There was no difference in the degree of fragmentation. In the retrospective clinical study, specimen adequacy was significantly higher among patients in the caudal orientation group (p = 0.0002, Mann-Whitney U test). CONCLUSION: Caudal orientation of the needle specimen notch of the biopsy device during TJLB produces superior core biopsy specimens. This simple technical modification may assist in obtaining higher-quality biopsy specimens during TJLB.


Assuntos
Biópsia por Agulha/métodos , Cirrose Hepática/patologia , Animais , Ascite/patologia , Transtornos da Coagulação Sanguínea/patologia , Bovinos , Humanos , Técnicas In Vitro , Radiografia Intervencionista , Estudos Retrospectivos , Ultrassonografia de Intervenção
17.
Acta Crystallogr C ; 69(Pt 4): 439-43, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23579723

RESUMO

Di(phenylpropylamino)gossypol [systematic name: 2,2'-bis{1,6-dihydroxy-5-isopropyl-8-[(3-phenylpropylamino)methylidene]naphthalen-7-one}, C48H52N2O6, was formed by reaction of the dimeric natural product gossypol with 3-phenylpropylamine. The structure of this compound has its two naphthalene ring systems oriented approximately perpendicular to each other, and the two pendant phenylpropyl groups have different conformations. One of these side groups is considerably disordered at room temperature but less so at 120 K. The enantiomeric molecules form centrosymmetric dimers that are supported by intermolecular hydrogen bonds and by hydrophobic interactions between a pair of naphthalene rings. Two additional hydrogen bonds tie the dimer pairs into layers. Unlike gossypol and many gossypol Schiff base derivatives, the title compound crystallizes without the inclusion of solvent, which appears to occur because of the size and flexibility of its phenylpropyl pendent groups.


Assuntos
Produtos Biológicos/química , Gossipol/química , Naftalenos/química , Propilaminas/química , Bases de Schiff/química , Solventes/química , Cristalografia por Raios X , Gossipol/análogos & derivados , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo
18.
J Agric Food Chem ; 60(10): 2740-5, 2012 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-22324794

RESUMO

Racemic gossypol and its related derivatives gossypolone and apogossypolone demonstrated significant growth inhibition against a diverse collection of filamentous fungi that included Aspergillus flavus, Aspergillus parasiticus, Aspergillus alliaceus, Aspergillus fumigatus, Fusarium graminearum, Fusarium moniliforme, Penicillium chrysogenum, Penicillium corylophilum, and Stachybotrys atra. The compounds were tested in a Czapek agar medium at a concentration of 100 µg/mL. Racemic gossypol and apogossypolone inhibited growth by up to 95%, whereas gossypolone effected 100% growth inhibition in all fungal isolates tested except A. flavus. Growth inhibition was variable during the observed time period for all tested fungi capable of growth in these treatment conditions. Gossypolone demonstrated significant aflatoxin biosynthesis inhibition in A. flavus AF13 (B(1), 76% inhibition). Apogossypolone was the most potent aflatoxin inhibitor, showing greater than 90% inhibition against A. flavus and greater than 65% inhibition against A. parasiticus (B(1), 67%; G(1), 68%). Gossypol was an ineffectual inhibitor of aflatoxin biosynthesis in both A. flavus and A. parasiticus. Both gossypol and apogossypolone demonstrated significant inhibition of ochratoxin A production (47%; 91%, respectively) in cultures of A. alliaceus.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Gossipol/farmacologia , Penicillium/efeitos dos fármacos , Extratos Vegetais/farmacologia , Aflatoxinas/biossíntese , Antifúngicos/metabolismo , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Gossypium/química , Gossipol/análogos & derivados , Penicillium/crescimento & desenvolvimento , Penicillium/metabolismo
19.
Carbohydr Res ; 346(16): 2551-7, 2011 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-22015400

RESUMO

D-Glucaric acid was characterized in solution by comparing NMR spectra from the isotopically unlabeled molecule with those from D-glucaric acid labeled with deuterium or carbon-13 atoms. The NMR studies provided unequivocal assignments for all carbon atoms and non-hydroxyl protons of the molecule. The crystal structure of D-glucaric acid was obtained by X-ray diffraction techniques and the structure was a close match to the low energy conformation generated from a Monte-Carlo-based searching protocol employing the MM3 molecular mechanics program. The molecule adopts a bent structure in both the crystalline and computationally generated lowest-energy structure, a conformation that is devoid of destabilizing eclipsed 1,3-hydroxyl interactions.


Assuntos
Ácido Glucárico/química , Modelos Moleculares , Configuração de Carboidratos , Isótopos de Carbono/química , Cristalografia por Raios X , Deutério/química , Espectroscopia de Ressonância Magnética , Método de Monte Carlo
20.
Ecology ; 92(3): 568-75, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21608465

RESUMO

Data on fine-scale animal movement are being collected worldwide, with the number of species being tagged and the resolution of data rapidly increasing. In this study, a general methodology is proposed to understand the patterns in these high-resolution movement time series that relate to marine animal behavior. The approach is illustrated with dive data from a northern fur seal (Callorhinus ursinus) tagged on the Pribilof Islands, Alaska, USA. We apply a state-space model composed of a movement model and corresponding high-resolution vertical movement data. The central goal is to estimate parameters of this movement model, particularly their variation on appropriate time scales, thereby providing a direct link to behavior. A particle filter with state augmentation is used to jointly estimate the movement parameters and the state. A multiple iterated filter using overlapping data segments is implemented to match the parameter time scale with the behavioral inference. The time variation in the auto-covariance function facilitates identification of a movement model, allows separation of observation and process noise, and provides for validation of results. The analysis yields fitted parameters that show distinct time-evolving changes in fur seal behavior over time, matching well what is observed in the original data set.


Assuntos
Mergulho/fisiologia , Otárias/fisiologia , Modelos Biológicos , Animais , Telemetria
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