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1.
Lancet ; 400(10369): 2161-2163, 2022 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-36528366
3.
Rev. peru. biol. (Impr.) ; 28(1): e19759, Jan-Mar 2021. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1289890

RESUMO

Resumen Presentamos el registro de un individuo de oso hormiguero norteño (Tamandua mexicana) con color de pelaje anormalmente blanco. Este individuo fue fotografiado con una cámara trampa en el bosque seco ecuatorial en el departamento de Lambayeque, a 560 m de altitud, en del noroeste del Perú. No pudimos diferenciar si la causa de esta aberración cromática correspondió a un caso de albinismo o de leucismo, sin embargo, destacamos este primer registro excepcional para la especie en Perú. Adicionalmente, hacemos una revisión de su presencia en el extremo sur de su distribución global.


Abstract We present the record of an individual of northern tamandua (Tamandua mexicana) with abnormal white coloration that was photographed with a camera trap in the equatorial dry forest in the department of Lambayeque, at elevation of 560 m, northwest Peru. We could not determine if this chromatic aberration was a case of leucism or albinism, but we highlight this uncommon record as the first for Peru. We also revised the information about its presence in the southern portion of its global range.

4.
Geohealth ; 4(9): e2020GH000277, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33005839

RESUMO

The H1N1 "Spanish influenza" pandemic of 1918-1919 caused the highest known number of deaths recorded for a single pandemic in human history. Several theories have been offered to explain the virulence and spread of the disease, but the environmental context remains underexamined. In this study, we present a new environmental record from a European, Alpine ice core, showing a significant climate anomaly that affected the continent from 1914 to 1919. Incessant torrential rain and declining temperatures increased casualties in the battlefields of World War I (WWI), setting the stage for the spread of the pandemic at the end of the conflict. Multiple independent records of temperature, precipitation, and mortality corroborate these findings.

5.
J Neurosci Res ; 98(3): 471-480, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31544973

RESUMO

BioLuminescent (BL) light production can modulate neural activity and behavior through co-expressed OptoGenetic (OG) elements, an approach termed "BL-OG." Yet, the relationship between BL-OG effects and bioluminescent photon emission has not been characterized in vivo. Further, the degree to which BL-OG effects strictly depend on optogenetic mechanisms driven by bioluminescent photons is unknown. Crucial to every neuromodulation method is whether the activator shows a dynamic concentration range driving robust, selective, and nontoxic effects. We systematically tested the effects of four key components of the BL-OG mechanism (luciferin, oxidized luciferin, luciferin vehicle, and bioluminescence), and compared these against effects induced by the Luminopsin-3 (LMO3) BL-OG molecule, a fusion of slow burn Gaussia luciferase (sbGLuc) and Volvox ChannelRhodopsin-1 (VChR1). We performed combined bioluminescence imaging and electrophysiological recordings while injecting specific doses of Coelenterazine (substrate for sbGluc), Coelenteramide (CTM, the oxidized product of CTZ), or CTZ vehicle. CTZ robustly drove activity in mice expressing LMO3, with photon production proportional to firing rate. In contrast, low and moderate doses of CTZ, CTM, or vehicle did not modulate activity in mice that did not express LMO3. We also failed to find bioluminescence effects on neural activity in mice expressing an optogenetically nonsensitive LMO3 variant. We observed weak responses to the highest dose of CTZ in control mice, but these effects were significantly smaller than those observed in the LMO3 group. These results show that in neocortex in vivo, there is a large CTZ range wherein BL-OG effects are specific to its active chemogenetic mechanism.


Assuntos
Medições Luminescentes , Neocórtex/fisiologia , Neurônios/fisiologia , Optogenética/métodos , Animais , Channelrhodopsins/fisiologia , Feminino , Imidazóis/administração & dosagem , Substâncias Luminescentes/administração & dosagem , Proteínas Luminescentes , Masculino , Camundongos Endogâmicos C57BL , Neocórtex/efeitos dos fármacos , Opsinas/fisiologia , Pirazinas/administração & dosagem , Reprodutibilidade dos Testes
6.
Geohealth ; 2(5): 162-170, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-32159523

RESUMO

Understanding the context from which evidence emerges is of paramount importance in reaching robust conclusions in scientific inquiries. This is as true of the present as it is of the past. In a trans-disciplinary study such as More et al. (2017, https://doi.org/10.1002/2017GH000064) and many others appearing in this and similar journals, a proper analysis of context demands the use of historical evidence. This includes demographic, epidemiological, and socio-economic data-common in many studies of the impact of anthropogenic pollution on human health-and, as in this specific case, also geoarchaeological evidence. These records anchor climate and pollution data in the geographic and human circumstances of history, without which we lose a fundamental understanding of the data itself. This article addresses Hinkley (2018, https://doi.org/10.1002/2017GH000105) by highlighting the importance of context, focusing on the historical and archaeological evidence, and then discussing atmospheric deposition and circulation in the specific region of our study. Since many of the assertions in Bindler (2018, https://doi.org/10.1002/2018GH000135) are congruent with our findings and directly contradict Hinkley (2018), this reply refers to Bindler (2018), whenever appropriate, and indicates where our evidence diverges.

7.
Geohealth ; 1(4): 211-219, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32158988

RESUMO

Contrary to widespread assumptions, next-generation high (annual to multiannual) and ultra-high (subannual) resolution analyses of an Alpine glacier reveal that true historical minimum natural levels of lead in the atmosphere occurred only once in the last ~2000 years. During the Black Death pandemic, demographic and economic collapse interrupted metal production and atmospheric lead dropped to undetectable levels. This finding challenges current government and industry understanding of preindustrial lead pollution and its potential implications for human health of children and adults worldwide. Available technology and geographic location have limited previous ice core investigations. We provide new high- (discrete, inductively coupled plasma mass spectrometry, ICP-MS) and ultra-high resolution (laser ablation inductively coupled plasma mass spectrometry, LA-ICP-MS) records of atmospheric lead deposition extracted from the high Alpine glacier Colle Gnifetti, in the Swiss-Italian Alps. We show that contrary to the conventional wisdom, low levels at or approaching natural background occurred only in a single 4 year period in ~2000 years documented in the new ice core, during the Black Death (~1349-1353 C.E.), the most devastating pandemic in Eurasian history. Ultra-high chronological resolution allows for the first time detailed and decisive comparison of the new glaciochemical data with historical records. Historical evidence shows that mining activity ceased upwind of the core site from ~1349 to 1353, while concurrently on the glacier lead (Pb) concentrations-dated by layer counting confirmed by radiocarbon dating-dropped to levels below detection, an order of magnitude beneath figures deemed low in earlier studies. Previous assumptions about preindustrial "natural" background lead levels in the atmosphere-and potential impacts on humans-have been misleading, with significant implications for current environmental, industrial, and public health policy, as well as for the history of human lead exposure. Trans-disciplinary application of this new technology opens the door to new approaches to the study of the anthropogenic impact on past and present human health.

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