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1.
Healthc Manage Forum ; 26(3): 145-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24409582

RESUMO

An in-depth analysis of organizational risk management in healthcare, and in particular the concepts of Enterprise Risk Management (ERM), has identified a 5-part model that can be used by Canadian healthcare leaders as an evidence-supported approach to successful organizational risk management. The Model for Organizational Risk Management, termed "the Model," has been developed as a basis for linking the components of an ERM Framework into a Canadian health organization to overcome the barriers that commonly disrupt strategic risk management. The Model addresses how an ERM Framework can fit within an existing health organization by building off and enhancing existing processes and resources to ensure familiarity, acceptance, and sustainability of the risk management program. By approaching the Model in a stepwise fashion (based on individual organizational context), healthcare leaders are provided with a road map from which to advance their own organizational risk management program.


Assuntos
Administradores de Instituições de Saúde , Gestão de Riscos , Canadá , Humanos , Modelos Organizacionais , Gestão de Riscos/métodos , Inquéritos e Questionários
2.
Amyotroph Lateral Scler ; 10 Suppl 2: 101-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19929741

RESUMO

Cyanobacteria produce many neurotoxins including beta-methylamino-L-alanine (BMAA) that has been liked to amyotrophic lateral sclerosis (ALS) and neurodegenerative disease. A number of ALS cases have been diagnosed among residents of Enfield, NH, a town encompassing a lake with a history of cyanobacteria algal blooms. To investigate an association between toxic cyanobacterial blooms in New Hampshire and development of ALS, we reviewed records from our institution and other community databases to obtain demographic information on patients diagnosed with ALS within New England. We identified nine ALS patients who lived near Lake Mascoma in Enfield, NH, an incidence of sporadic ALS that is 10 to 25 times the expected incidence of 2/100,000/year. We suggest that the high incidence of ALS in this potential cluster could be directly related to chronic exposure to cyanobacterial neurotoxins such as BMAA. Possible routes of toxin exposure include inhalation of aerosolized toxins, consuming fish, or ingestion of lake water. Further investigation, including analysis of brain tissue for cyanobacterial toxins, will be helpful to test for an association between BMAA and ALS.


Assuntos
Diamino Aminoácidos/toxicidade , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/etiologia , Cianobactérias/fisiologia , Diamino Aminoácidos/análise , Esclerose Lateral Amiotrófica/diagnóstico , Cromatografia Líquida de Alta Pressão/métodos , Análise por Conglomerados , Cianobactérias/química , Toxinas de Cianobactérias , Ecossistema , Eucariotos/microbiologia , Humanos , Incidência , New Hampshire/epidemiologia , Ficocianina/análise , Estudos Retrospectivos , Espectrometria de Massas em Tandem/métodos , Microbiologia da Água
3.
Elife ; 62017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28168949

RESUMO

Voltage- and calcium-dependent BK channels regulate calcium-dependent cellular events such as neurotransmitter release by limiting calcium influx. Their plasma membrane abundance is an important factor in determining BK current and thus regulation of calcium-dependent events. In C. elegans, we show that ERG-28, an endoplasmic reticulum (ER) membrane protein, promotes the trafficking of SLO-1 BK channels from the ER to the plasma membrane by shielding them from premature degradation. In the absence of ERG-28, SLO-1 channels undergo aspartic protease DDI-1-dependent degradation, resulting in markedly reduced expression at presynaptic terminals. Loss of erg-28 suppressed phenotypic defects of slo-1 gain-of-function mutants in locomotion, neurotransmitter release, and calcium-mediated asymmetric differentiation of the AWC olfactory neuron pair, and conferred significant ethanol-resistant locomotory behavior, resembling slo-1 loss-of-function mutants, albeit to a lesser extent. Our study thus indicates that the control of BK channel trafficking is a critical regulatory mechanism for synaptic transmission and neural function.


Assuntos
Álcoois/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Proteínas de Transporte/metabolismo , Retículo Endoplasmático/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Proteínas de Membrana/metabolismo , Sinapses/fisiologia , Animais , Transporte Proteico
4.
Toxicon ; 48(5): 580-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16928388

RESUMO

Zooplankton accumulate microcystins (MC), a potent cyanobacteria toxin, and therefore may act as vectors of the toxin up the aquatic food web; however this transfer has not yet been quantified. In addition there is a lack of information regarding fish's ability to metabolize MC when administered a low dose over a longer period of time. We monitored MC concentrations in three levels of an aquatic food web: phytoplankton, zooplankton, and sunfish (Lepomis gibbosus). Bosmina appeared to be both a major accumulator of MC in zooplankton and the major vector of MC to sunfish. In an accumulation experiment, sunfish were brought into the laboratory and fed MC-rich zooplankton pellets (50 ng MC kg(-1)d(-1)) for 9 days. Zooplankton directly transferred MC to sunfish, resulting in liver and muscle tissue accumulation. However, after 6 days of accumulation fish significantly decreased concentrations in their liver and muscle tissue, indicating the induction of a detoxification and excretion pathway. Sunfish retained MC in their liver and muscle tissue, showing no significant changes in toxin concentration over 2 weeks of fasted depuration.


Assuntos
Toxinas Bacterianas/farmacocinética , Cianobactérias/metabolismo , Cadeia Alimentar , Peptídeos Cíclicos/farmacocinética , Perciformes/metabolismo , Plâncton/metabolismo , Animais , Toxinas Bacterianas/análise , Ecossistema , Inativação Metabólica , Fígado/metabolismo , Microcistinas , Músculo Esquelético/metabolismo , Peptídeos Cíclicos/análise , Fitoplâncton/química , Fitoplâncton/metabolismo , Plâncton/química , Zooplâncton/química , Zooplâncton/metabolismo
5.
Toxins (Basel) ; 7(2): 322-36, 2015 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-25643180

RESUMO

A cluster of amyotrophic lateral sclerosis (ALS) has been previously described to border Lake Mascoma in Enfield, NH, with an incidence of ALS approximating 25 times expected. We hypothesize a possible association with cyanobacterial blooms that can produce ß-N-methylamino-L-alanine (BMAA), a neurotoxic amino acid implicated as a possible cause of ALS/PDC in Guam. Muscle, liver, and brain tissue samples from a Lake Mascoma carp, as well as filtered aerosol samples, were analyzed for microcystins (MC), free and protein-bound BMAA, and the BMAA isomers 2,4-diaminobutyric acid (DAB) and N-(2-aminoethyl)glycine (AEG). In carp brain, BMAA and DAB concentrations were 0.043 µg/g ± 0.02 SD and 0.01 µg/g ± 0.002 SD respectively. In carp liver and muscle, the BMAA concentrations were 1.28 µg/g and 1.27 µg/g respectively, and DAB was not detected. BMAA was detected in the air filters, as were the isomers DAB and AEG. These results demonstrate that a putative cause for ALS, BMAA, exists in an environment that has a documented cluster of ALS. Although cause and effect have not been demonstrated, our observations and measurements strengthen the association.


Assuntos
Diamino Aminoácidos/análise , Esclerose Lateral Amiotrófica , Cianobactérias/crescimento & desenvolvimento , Lagos/química , Microcistinas/análise , Poluentes Químicos da Água/análise , Diamino Aminoácidos/farmacocinética , Diamino Aminoácidos/toxicidade , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/etiologia , Animais , Encéfalo/metabolismo , Carpas/crescimento & desenvolvimento , Cromatografia Líquida , Cianobactérias/metabolismo , Toxinas de Cianobactérias , Monitoramento Ambiental , Eutrofização , Cadeia Alimentar , Humanos , Lagos/microbiologia , Limite de Detecção , Fígado/química , Microcistinas/toxicidade , Músculo Esquelético/química , New Hampshire , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/farmacocinética , Poluentes Químicos da Água/toxicidade
6.
Oecologia ; 45(1): 94-103, 1980 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28310943

RESUMO

Isolated female D. leptopus oscillate between gravid and nongravid reproductive conditions. When gravid, the oviducts are visible as a pair of dark bands lateral to the digestive tract. Periodically the females revert to a nongravid condition by releasing all the unfertilized oocytes into the environment. The oviducts then remain transparent until they refill with ripe gametes.The characteristics of this gametogenic cycle were defined at 18° C using females cultured under controlled conditions. The average period of the cycle was 4.4 days, with a gravid phase (dark oviducts) of 3.4 days and a nongravid phase (clear oviducts) of 0.9 days. Observations made in situ confirmed the oscillatory nature of the changes in reproductive status.The duration of the nongravid phase was shown to represent the minimal time interval between successive clutches of fertilized eggs. Estimates of maximal rates of clutch production based on this measure were more than three times higher than those based on the duration of embryonic development.Since unfertilized oocytes disintegrate upon extrusion, a considerable amount of reproductive material may be wasted regularly. A turnover rate of 5.6% body weight (dry) day-1 was calculated for isolated females at 18° C. A model used to estimate the frequency of mating interactions indicated that the probability of oocyte extrusion in lakes may be high and the impact on nutrient pools could be substantial. Up to 0.12 µg phosphorus mg-1 h-1 may be released in the form of unfertilized oocytes.

7.
Environ Toxicol ; 22(3): 337-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17497639

RESUMO

Gloeotrichia echinulata is a bloom-forming cyanobacterium that is common in eutrophic lakes, and less prevalent but increasing in oligotrophic lakes. We used an enzyme-linked immunosorbent assay analysis to test for the presence of the hepatotoxin microcystin-LR (MC-LR) in G. echinulata collected from an oligotrophic lake in central New Hampshire, USA. We found that G. echinulata contained MC-LR at mean concentrations of 97.07 +/- 7.78 (1 s.e.) ng MC-LR g(-1) dry wt colonies. This suggests that recent outbreaks of G. echinulata in oligotrophic lakes used as water sources throughout New England (USA) may pose a health concern. The toxicity of G. echinulata reported here suggests the need for future monitoring of microcystins in oligotrophic lakes.


Assuntos
Cianobactérias/química , Cianobactérias/metabolismo , Microcistinas/química , Microcistinas/isolamento & purificação , Microbiologia da Água , Ensaio de Imunoadsorção Enzimática , Toxinas Marinhas
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