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1.
Ecol Appl ; 32(7): e2673, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35584048

RESUMO

Marine heatwaves threaten the persistence of kelp forests globally. However, the observed responses of kelp forests to these events have been highly variable on local scales. Here, we synthesize distribution data from an environmentally diverse region to examine spatial patterns of canopy kelp persistence through an unprecedented marine heatwave. We show that, although often overlooked, temperature variation occurring at fine spatial scales (i.e., a few kilometers or less) can be a critical driver of kelp forest persistence during these events. Specifically, though kelp forests nearly all persisted toward the cool outer coast, inshore areas were >3°C warmer at the surface and experienced extensive kelp loss. Although temperatures remained cool at depths below the thermocline, kelp persistence in these thermal refugia was strongly constrained by biotic interactions, specifically urchin populations that increased during the heatwave and drove transitions to urchin barrens in deeper rocky habitat. Urchins were, however, largely absent from mixed sand and cobble benthos, leading to an unexpected association between bottom substrate and kelp forest persistence at inshore sites with warm surface waters. Our findings demonstrate both that warm microclimates increase the risk of habitat loss during marine heatwaves and that biotic interactions modified by these events will modulate the capacity of cool microclimates to serve as thermal refugia.


Assuntos
Kelp , Mudança Climática , Ecossistema , Florestas , Kelp/fisiologia , Microclima , Areia
2.
Clin Obstet Gynecol ; 65(2): 334-346, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35125391

RESUMO

Within this review, the literature and outcomes from animal models of maternal marijuana use and cigarette smoking are summarized. The existing data demonstrate that prenatal marijuana and nicotine exposure both have multifaceted adverse effects on maternal, gestational, placental, and fetal outcomes. These include placental function and development, fetal growth and birth weight, and offspring neurodevelopment.


Assuntos
Cannabis , Efeitos Tardios da Exposição Pré-Natal , Animais , Cannabis/efeitos adversos , Feminino , Humanos , Modelos Animais , Placenta , Gravidez , Nicotiana
3.
F S Sci ; 2(3): 287-294, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34901892

RESUMO

OBJECTIVE: To determine the dose-dependent effect of contemporary marijuana exposure on female menstrual cyclicity and reproductive endocrine physiology in a nonhuman primate model. DESIGN: Research animal study. SETTING: Research institute environment. ANIMALS: Adult female rhesus macaques (6-12 years of age; n = 8). INTERVENTIONS: Daily delta-9-tetrahydrocannabinol (THC) edible at medically and recreationally relevant contemporary doses. MAIN OUTCOME MEASURES: Menstrual cycle length (MCL), anti-Müllerian hormone, prolactin, basal follicle-stimulating hormone (FSH), estradiol (E2) and progesterone, luteinizing hormone (LH), and thyroid-stimulating hormone. RESULTS: The average before THC weight was 6.9 kg (standard deviation, 0.8), and at the highest THC dosing, the average weight was 7.2 kg (standard deviation, 0.8). With increasing THC dosing, MCL and FSH concentrations increased, while basal E2 concentration was stable. The average MCL concentration increased 4.0 days for each mg/7 kg/day of THC (95% CI, 1.4-6.6 days). Follicle-stimulating hormone concentration increased significantly with increasing THC dose, 0.34 ng/mL for each mg/7 kg/day of THC (95% CI, 0.14-0.57 ng/mL). No significant trends were observed between THC dosing and average basal progesterone, anti-Müllerian hormone, prolactin, LH, or thyroid-stimulating hormone concentrations. CONCLUSIONS: In rhesus macaques, a dose response toward increased MCL and basal FSH concentrations but plateau of basal E2 and LH concentrations was observed with increasing THC dosing, suggesting ovulatory dysfunction. Further studies are needed to determine the effects of a longer duration of exposure and whether the significant increase in MCL and FSH concentrations results in reduced fecundity.


Assuntos
Dronabinol , Progesterona , Animais , Hormônio Antimülleriano , Dronabinol/farmacologia , Feminino , Hormônio Foliculoestimulante , Hormônio Luteinizante , Macaca mulatta , Ciclo Menstrual , Periodicidade , Prolactina , Saúde Reprodutiva , Tireotropina
4.
Curr Opin Endocrinol Diabetes Obes ; 28(6): 566-573, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34545843

RESUMO

PURPOSE OF REVIEW: The aim of this review is to evaluate biological, life history, environmental, and lifestyle factors and exposures that cause variability in menstrual cycle length (MCL). RECENT FINDINGS: Recent literature has detailed a number of factors that influence MCL, with particular emphasis placed on novel environmental exposures, such as air pollution and endocrine disrupting chemicals. SUMMARY: MCL varies widely in response to intrinsic and extrinsic inputs and is a useful predictor of reproductive health and fecundability. VIDEO ABSTRACT: http://links.lww.com/COE/A28.


Assuntos
Disruptores Endócrinos , Ciclo Menstrual , Disruptores Endócrinos/toxicidade , Exposição Ambiental , Feminino , Fertilidade , Humanos
5.
PLoS One ; 14(9): e0216767, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31536494

RESUMO

The bioaccumulation of Potentially Toxic Elements (PTEs) by benthic invertebrates in estuarine sediments is poorly understood. We sampled and analysed PTEs in sediments and benthic invertebrates from five sites in the Skeena Estuary (British Columbia, Canada), including sites adjacent to an abandoned cannery and a decommissioned papermill. Our aim was to elucidate baseline levels of PTE concentrations at sites that may be recovering from disturbance associated with prior industrial development and identify organisms that could be used to biomonitor the impact of future industrial developments. There was no indication that sediments of the salmon cannery were polluted, but acidic sediments adjacent to the papermill contained elevated concentrations of Cd, Cr, Hg and Pb. Benthic invertebrate community assemblages confirm that sediments have mostly recovered from prior industrial development associated with discharge of papermill sludge. Overall, we did not observe any relationship between PTE concentrations in the sediment and PTE concentrations in invertebrate tissues. However, we did observe a negative relationship between sediment pH and the Biota-Sediment Accumulation Factor (BSAF) of most PTEs for Oregon pill bugs (Gnorimosphaeroma oregonensis). G. oregonensis, observed at all sites, feeds on the fibers associated with the papermill discharge. Thus, G. oregonensis is a useful biomonitors for quantifying the impact of the decommissioned papermill, and are candidate biomonitors for assessing the impact of similar industrial development projects on intertidal ecosystems.


Assuntos
Bioacumulação , Sedimentos Geológicos/química , Invertebrados/química , Toxinas Biológicas/química , Animais , Colúmbia Britânica , Ecossistema , Toxinas Biológicas/análise
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