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1.
Am J Bot ; 110(6): e16156, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36934437

RESUMO

PREMISE: Animal pollinators play an important role in pollen dispersal. Here, we assessed differences in pollen and seed dispersal and the role of pollinator functional groups with different foraging behaviors in generating patterns of genetic diversity over similar geographic ranges for two closely related taxa. We focused on two members of Oenothera section Calylophus (Onagraceae) that co-occur on gypsum outcrops throughout the northern Chihuahuan Desert but differ in floral phenotype and primary pollinator: Oenothera gayleana (bee) and O. hartwegii subsp. filifolia (hawkmoth). METHODS: We measured breeding system and floral traits and studied gene flow and population differentiation at the local (<13 km; four populations) and landscape (60-440 km; five populations) scales using 10-11 nuclear (pollen dispersal) and three plastid (seed dispersal) microsatellite markers. RESULTS: Both taxa were self-incompatible and floral traits were consistent with expectations for different pollinators. Seed and pollen dispersal patterns were distinctly different for both species. We found no evidence of genetic structure at the local scale but did at the landscape scale; O. gayleana showed greater differentiation and significant isolation by distance than in O. hartwegii subsp. filifolia. The plastid data were consistent with gravity dispersal of seeds and suggest that pollen dispersal is the principal driver of genetic structure in both species. CONCLUSIONS: We demonstrated that pollinator functional groups can impact genetic differentiation in different and predictable ways. Hawkmoths, with larger foraging distances, can maintain gene flow across greater spatial scales than bees.


Assuntos
Mariposas , Oenothera , Onagraceae , Abelhas/genética , Animais , Polinização , Melhoramento Vegetal , Pólen/genética , Flores
2.
Front Plant Sci ; 8: 1383, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28890721

RESUMO

Actinidia eriantha Benth. is a diploid perennial woody vine native to China and is recognized as a valuable species for commercial kiwifruit improvement with high levels of ascorbic acid as well as having been used in traditional Chinese medicine. Due to the lack of genomic resources for the species, microsatellite markers for population genetics studies are scarce. In this study, RNASeq was conducted on fruit tissue of A. eriantha, yielding 5,678,129 reads with a total output of 3.41 Gb. De novo assembly yielded 69,783 non-redundant unigenes (41.3 Mb), of which 21,730 were annotated using protein databases. A total of 8,658 EST-SSR loci were identified in 7,495 unigene sequences, for which primer pairs were successfully designed for 3,842 loci (44.4%). Among these, 183 primer pairs were assayed for PCR amplification, yielding 69 with detectable polymorphism in A. eriantha. Additionally, 61 of the 69 polymorphic loci could be successfully amplified in at least one other Actinidia species. Of these, 14 polymorphic loci (mean NA = 6.07 ± 2.30) were randomly selected for assessing levels of genetic diversity and population structure within A. eriantha. Finally, a neighbor-joining tree and Bayesian clustering analysis showed distinct clustering into two groups (K = 2), agreeing with the geographical distributions of these populations. Overall, our results will facilitate further studies of genetic diversity within A. eriantha and will aid in discriminating outlier loci involved in local adaptation.

3.
Public Health Res Pract ; 26(1): e2611603, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26863166

RESUMO

On 1 July 2015, the Australian Government established 31 new Primary Health Networks (PHNs), following a review by its former Chief Medical Officer, John Horvath, of 61 Medicare Locals created under the previous Labor administration. The Horvath review recommended, among other things, that new, larger primary health organisations be established to reduce fragmentation of care by integrating and coordinating health services, supporting the role of general practice, and leveraging and administering health program funding. The two main objectives of the new PHNs, as stated on the Department of Health's website, are "increasing the efficiency and effectiveness of medical services for patients, particularly those at risk of poor health outcomes, and improving coordination of care to ensure patients receive the right care in the right place at the right time". Below are three viewpoints, commissioned for this primary health care themed issue of Public Health Research & Practice, from the Australian Government Department of Health, the Public Health Association of Australia and a Sydney-based PHN. We asked the authors to focus particularly on how the newly established networks might help to integrate public health within the primary health care landscape. Our authors have pointed out the huge overlap between public health and primary care and looked at evidence showing the great benefits for health systems of collaboration between the two. Challenges ahead include a possible government focus on delivery of 'frontline' medical services, which may come at the expense of population health, and the complexity of dealing with all primary health care stakeholders, including health professionals, Local Health Districts, nongovernment organisations, research institutions and local communities.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Atenção Primária à Saúde , Administração em Saúde Pública , Austrália , Humanos , Inovação Organizacional
4.
Mol Phylogenet Evol ; 80: 169-85, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25109653

RESUMO

Crown clade Apocynaceae comprise seven primary lineages of lianas, shrubs, and herbs with a diversity of pollen aggregation morphologies including monads, tetrads, and pollinia, making them an ideal group for investigating the evolution and function of pollen packaging. Traditional molecular systematic approaches utilizing small amounts of sequence data have failed to resolve relationships along the spine of the crown clade, a likely ancient rapid radiation. The previous best estimate of the phylogeny was a five-way polytomy, leaving ambiguous the homology of aggregated pollen in two major lineages, the Periplocoideae, which possess pollen tetrads, and the milkweeds (Secamonoideae plus Asclepiadoideae), which possess pollinia. To assess whether greatly increased character sampling would resolve these relationships, a plastome sequence data matrix was assembled for 13 taxa of Apocynaceae, including nine newly generated complete plastomes, one partial new plastome, and three previously reported plastomes, collectively representing all primary crown clade lineages and outgroups. The effects of phylogenetic noise, long-branch attraction, and model selection (linked versus unlinked branch lengths among data partitions) were evaluated in a hypothesis-testing framework based on Shimodaira-Hasegawa tests. Discrimination among alternative crown clade resolutions was affected by all three factors. Exclusion of the noisiest alignment positions and topologies influenced by long-branch attraction resulted in a trichotomy along the spine of the crown clade consisting of Rhabdadenia+the Asian clade, Baisseeae+milkweeds, and Periplocoideae+the New World clade. Parsimony reconstruction on all optimal topologies after noise exclusion unambiguously supports parallel evolution of aggregated pollen in Periplocoideae (tetrads) and milkweeds (pollinia). Our phylogenomic approach has greatly advanced the resolution of one of the most perplexing radiations in Apocynaceae, providing the basis for study of convergent floral morphologies and their adaptive value.


Assuntos
Apocynaceae/classificação , Evolução Biológica , Genoma de Cloroplastos , Filogenia , Apocynaceae/genética , Teorema de Bayes , DNA de Plantas/genética , Funções Verossimilhança , Modelos Genéticos , Pólen/genética , Análise de Sequência de DNA
5.
Biochemistry ; 53(18): 2926-40, 2014 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-24785783

RESUMO

Strains lacking and overexpressing the vacuolar iron (Fe) importer CCC1 were characterized using Mössbauer and EPR spectroscopies. Vacuolar Fe import is impeded in Δccc1 cells and enhanced in CCC1-up cells, causing vacuolar Fe in these strains to decline and accumulate, respectively, relative to WT cells. Cytosolic Fe levels should behave oppositely. The Fe content of Δccc1 cells grown under low-Fe conditions was similar to that in WT cells. Most Fe was mitochondrial with some nonheme high spin (NHHS) Fe(II) present. Δccc1 cells grown with increasing Fe concentration in the medium contained less total Fe, less vacuolar HS Fe(III), and more NHHS Fe(II) than in comparable WT cells. As the Fe concentration in the growth medium increased, the concentration of HS Fe(III) in Δccc1 cells increased to just 60% of WT levels, while NHHS Fe(II) increased to twice WT levels, suggesting that the NHHS Fe(II) was cytosolic. Δccc1 cells suffered more oxidative damage than WT cells, suggesting that the accumulated NHHS Fe(II) promoted Fenton chemistry. The Fe concentration in CCC1-up cells was higher than in WT cells; the extra Fe was present as NHHS Fe(II) and Fe(III) and as Fe(III) oxyhydroxide nanoparticles. These cells contained less mitochondrial Fe and exhibited less ROS damage than Δccc1 cells. CCC1-up cells were adenine-deficient on minimal medium; supplementing with adenine caused a decline of NHHS Fe(II) suggesting that some of the NHHS Fe(II) that accumulated in these cells was associated with adenine deficiency rather than the overexpression of CCC1. A mathematical model was developed that simulated changes in Fe distributions. Simulations suggested that only a modest proportion of the observed NHHS Fe(II) in both strains was the cytosolic form of Fe that is sensed by the Fe import regulatory system. The remainder is probably generated by the reduction of the vacuolar NHHS Fe(III) species.


Assuntos
Proteínas de Transporte de Cátions/química , Ferro/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Adenina/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Simulação por Computador , Citosol/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Compostos Férricos/metabolismo , Compostos Ferrosos/metabolismo , Manganês/metabolismo , Mitocôndrias/metabolismo , Modelos Biológicos , Ferroproteínas não Heme/metabolismo , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Espectroscopia de Mossbauer , Vacúolos/metabolismo
6.
Environ Pollut ; 152(1): 205-16, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17611007

RESUMO

A small population of endangered northern bottlenose whales (Hyperoodon ampullatus) inhabits "The Gully" a Marine Protected Area on the Scotian Shelf, eastern Canada. Amid concerns regarding nearby oil and gas development, we took 36 skin and blubber biopsy samples in 1996-1997 (prior to major development) and 2002-2003 (five years after development began), and three samples from a population in the Davis Strait, Labrador in 2003. These were analysed for cytochrome P4501A1 (CYP1A1) protein expression (n=36), and for persistent contaminants (n=23). CYP1A1 showed generally low expression in whales from The Gully, but higher levels during 2003, potentially coincident with recorded oil spills, and higher levels in Davis Strait whales. A range of PCB congeners and organochlorine compounds were detected, with concentrations similar to other North Atlantic odontocetes. Concentrations were higher in whales from The Gully than from the Davis Strait, with significant increases in 4,4'-DDE and trans-nonachlor in 2002-2003 relative to 1996-1997.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Indústrias , Petróleo , Poluentes Químicos da Água/análise , Baleias/metabolismo , Tecido Adiposo/química , Tecido Adiposo/metabolismo , Animais , Biópsia , Canadá , Citocromo P-450 CYP1A1/análise , Monitoramento Ambiental/métodos , Geografia , Hidrocarbonetos Clorados/análise , Bifenilos Policlorados/análise
7.
Mol Vis ; 13: 1783-92, 2007 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-17960131

RESUMO

PURPOSE: To evaluate the efficacy of intravitreal injection of GDNF-loaded biodegradable microspheres in promoting the survival of retinal ganglion cells (RGCs) and their axons in a rat model of chronically elevated intraocular pressure (IOP). METHODS: Chronic elevation of IOP was induced in Brown Norway rats through injection of hypertonic saline (1.9 M) into the episcleral veins. After injection, IOP was measured twice a week in rats using topical anesthesia. Poly DL-lactide-co-glycolide (PLGA) microspheres were fabricated using a modified version of the spontaneous emulsification technique. Two and ten percent of volume solutions of microspheres loaded with glial cell line-derived neurotrophic factor (GDNF) were injected into the vitreous cavity of rats with elevated IOP, with injections of blank microspheres and PBS serving as controls. Histological analysis was used to quantify surviving RGCs and axons and provide comparison among different groups. In addition, the thickness of the retinal inner plexiform layer (IPL) and the level of glial fibrillary acidic protein (GFAP) expression within the retina and optic nerve were quantitatively compared. RESULTS: IOP was significantly increased in eyes with episcleral vein injection over untreated eyes (p<0.001) but did not show a significant difference among groups that received intravitreal injections of GDNF microspheres, blank microspheres, or PBS (p=0.1852). The duration of IOP elevation in this experiment was eight weeks. Expression of GDNF and its receptors localizes to the adult rat RGCs. Ten percent of the GDNF microsphere treatment significantly increased RGC survival and axon survival (p<0.001), reduced the loss of retinal IPL thickness (p<0.001), and decreased glial cell activation in the retina and optic nerve (p<0.001) compared with blank microspheres and PBS. In addition, GDNF microsphere treatment moderately reduced cupping of the optic nerve head. CONCLUSIONS: Delivery of GDNF via biodegradable microspheres significantly increased the survival of RGCs and their axons, preserved IPL thickness, and decreased retina and optic nerve glial cell activation in an experimental glaucoma model. This study suggests that GDNF delivered by PLGA microspheres may be useful as a neuroprotective tool in the treatment of glaucomatous optic neuropathy.


Assuntos
Glaucoma/fisiopatologia , Fator Neurotrófico Derivado de Linhagem de Célula Glial/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Nervo Óptico/fisiopatologia , Retina/fisiopatologia , Implantes Absorvíveis , Animais , Axônios/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glaucoma/patologia , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/farmacologia , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Injeções , Pressão Intraocular/efeitos dos fármacos , Microesferas , Fármacos Neuroprotetores/farmacologia , Nervo Óptico/efeitos dos fármacos , Nervo Óptico/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Ratos , Ratos Endogâmicos BN , Retina/efeitos dos fármacos , Retina/metabolismo , Retina/patologia , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/patologia , Solução Salina Hipertônica/administração & dosagem , Solução Salina Hipertônica/farmacologia , Corpo Vítreo
8.
J Sch Health ; 77(5): 232-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17430435

RESUMO

BACKGROUND: There is debate about a 10% versus 15% of body weight cutoff point for safe weight of school backpacks. Estimation of the cutoff may be affected by use of survey methods and failure to assess pain experienced while wearing a backpack. Previous research also suggests that younger students and females are more at risk for developing backpack pain. METHODS: Five hundred and thirty-one 5th- to 12th-grade Northern California students and their backpacks were weighed. Students were individually interviewed about how often they experienced pain while carrying a backpack, the site of their pain, and if the pain had interfered with school activities or led to medical care. RESULTS: Data support the use of a 10% of body weight cutoff for safe use of backpacks for all grade levels. Younger students and females are more at risk due to relatively lower body weight while females also carry heavier backpacks than males. Greater relative backpack weight is associated with upper- and mid-back pain reports but not neck or lower back pain; it is also associated with lost school time, lost school sports time, and greater chiropractic utilization. CONCLUSIONS: The 10% cutoff is recommended along with a variety of practical methods to help schools achieve that goal for middle and high school students.


Assuntos
Dor nas Costas/prevenção & controle , Efeitos Psicossociais da Doença , Educação em Saúde , Remoção/efeitos adversos , Estudantes , Adolescente , Distribuição por Idade , Dor nas Costas/epidemiologia , Dor nas Costas/etiologia , Peso Corporal , California/epidemiologia , Criança , Quiroprática/estatística & dados numéricos , Análise Discriminante , Feminino , Humanos , Masculino , Risco , Distribuição por Sexo , Suporte de Carga
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