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1.
Animals (Basel) ; 13(19)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37835700

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been reported in multiple animal species besides humans. The goal of this study was to report clinical signs, infection progression, virus detection and antibody response in a group of wild felids housed in adjacent but neighboring areas at the Pittsburgh Zoo. Initially, five African lions (Panthera leo krugeri) housed together exhibited respiratory clinical signs with viral shedding in their feces in March of 2021 coinciding with infection of an animal keeper. During the second infection wave in December 2021, four Amur tigers (Panthera tigris altaica) and a Canadian lynx (Lynx canadensis) showed clinical signs and tested positive for viral RNA in feces. In infected animals, viral shedding in feces was variable lasting up to 5 weeks and clinical signs were observed for up to 4 weeks. Despite mounting an antibody response to initial exposure, lions exhibited respiratory clinical signs during the second infection wave, but none shed the virus in their feces. The lions were positive for alpha variant (B.1.1.7 lineage) during the first wave and the tiger and lynx were positive for delta variant (AY.25.1. lineage) during the second wave. The viruses recovered from felids were closely related to variants circulating in human populations at the time of the infection. Cheetahs (Acinonyx jubatus) in the park did not show either the clinical signs or the antibody response.

2.
BMC Geriatr ; 21(1): 143, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33637054

RESUMO

BACKGROUND: Confinement during the COVID-19 pandemic has placed great stress on older adults, which may be affecting their quality of life. Thus, this study aims to describe the changes in mental and physical health, isolation and loneliness, residence and socioeconomic resources in a national cohort of Chilean older adults before and during the COVID-19 outbreak. It also analyzes the changes in depressive symptoms by changes in the other quality of life indicators before and during the COVID-19 outbreak. Possible methodological biases of telephone surveys in older adults living in non-developed countries are also discussed. METHODS: Between June and September 2020, a random subsample of 720 people who had participated in the face-to-face V National Survey on Quality of Life in Older Adults in Chile conducted at the end of 2019 was followed up by telephone. Descriptive bivariate analyses were performed using t-test and non-parametric tests for independent variables, comparing the baseline sample with the current 2020 follow-up sample during the peak of the pandemic outbreak in Latin America. Furthermore, descriptive bivariate analysis through t-test and non-parametric test for paired samples compared the follow-up subsample at baseline with the not-included sample, examining possible biases of the telephone interview compared with the face-to-face interview. RESULTS: In the panel, there was no variation in self-rated health. The health symptoms that worsened were memory, stomach, and mood problems. Depressive symptoms and anxiety increased; similarly, smartphone users, social contacts, intergenerational co-residence and resilience increased. The telephone follow-up sample had a higher educational level and greater smartphone use than those not included in the subsample. CONCLUSIONS: Although some physical and mental health indicators have worsened during the pandemic, older adults mobilized resources that could allow them to maintain their quality of life, such as improved resilience. Thus, these findings can guide future research and the development of efficient strategies to improve these resources among older adults to ensure wellbeing.


Assuntos
COVID-19 , Qualidade de Vida , Idoso , Chile/epidemiologia , Humanos , Estudos Longitudinais , Pandemias , SARS-CoV-2
3.
Front Endocrinol (Lausanne) ; 11: 563165, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117280

RESUMO

GPER-1 is a novel membrane sited G protein-coupled estrogen receptor. Clinical studies have shown that patients suffering an estrogen receptor α (ERα)/GPER-1 positive, breast cancer have a lower survival rate than those who have developed ERα-positive/GPER-1 negative tumors. Moreover, absence of GPER-1 improves the prognosis of patients treated with tamoxifen, the most used selective estrogen receptor modulator to treat ERα-positive breast cancer. MCF-7 breast cancer cells were continuously treated with 1,000 nM tamoxifen for 7 days to investigate its effect on GPER-1 protein expression, cell proliferation and intracellular [Ca2+]i mobilization, a key signaling pathway. Breast cancer cells continuously treated with tamoxifen, exhibited a robust [Ca2+]i mobilization after stimulation with 1,000 nM tamoxifen, a response that was blunted by preincubation of cells with G15, a commercial GPER-1 antagonist. Continuously treated cells also displayed a high [Ca2+]i mobilization in response to a commercial GPER-1 agonist (G1) and to estrogen, in a magnitude that doubled the response observed in untreated cells and was almost completely abolished by G15. Proliferation of cells continuously treated with tamoxifen and stimulated with 2,000 nM tamoxifen, was also higher than that observed in untreated cells in a degree that was approximately 90% attributable to GPER-1. Finally, prolonged tamoxifen treatment did not increase ERα expression, but did overexpress the kinin B1 receptor, another GPCR, which we have previously shown is highly expressed in breast tumors and increases proliferation of breast cancer cells. Although we cannot fully extrapolate the results obtained in vitro to the patients, our results shed some light on the occurrence of drug resistance in breast cancer patients who are ERα/GPER-1 positive, have been treated with tamoxifen and display low survival rate. Overexpression of kinin B1 receptor may explain the increased proliferative response observed in breast tumors under continuous treatment with tamoxifen.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Receptores de Estrogênio/biossíntese , Receptores Acoplados a Proteínas G/biossíntese , Tamoxifeno/administração & dosagem , Neoplasias da Mama/patologia , Proliferação de Células/fisiologia , Feminino , Humanos , Células MCF-7 , Receptores Acoplados a Proteínas G/agonistas , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
4.
Environ Sci Pollut Res Int ; 27(27): 33890-33902, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32537689

RESUMO

The search for renewable fuels or components which may improve or replace fossil fuels is an important step towards a sustainable future. In particular, the pine oleoresin produced by conifer trees, which is composed by turpentine oil and non-volatile rosin, may be transformed into alternative fuels. In this work, combustion of six molecules which can be obtained from oleoresin either by distillation (i.e., α- and ß-pinene) or by further oxyfunctionalization (nopol, terpineol, myrtenol, and borneol) was studied to assess the potential of pine oleoresin as raw material for biofuels. Emission indices of the main pollutants (carbon monoxide-CO, unburned hydrocarbons-UHC, and nitrogen oxides-NOx) were obtained in non-premixed co-flow laminar flames of the oleoresin-derived molecules blended with n-heptane. The main characteristics of the flames (i.e., temperature and height) were also determined. Significant increase in flame temperature and reduction in CO and UHC emissions with respect to n-heptane were observed with nopol, terpineol, and myrtenol, along an increase in NOx emissions, suggesting an improvement in combustion performance. In addition, differences in emission indices, evidenced for these molecules (even between α- and ß-pinene), suggest the importance of the molecular structure in the combustion reaction.


Assuntos
Biocombustíveis/análise , Extratos Vegetais , Monóxido de Carbono/análise , Estrutura Molecular , Emissões de Veículos
5.
Transl Res ; 210: 57-79, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30904442

RESUMO

Radial glial cells (RGCs) are the neural stem/progenitor cells (NSPCs) that give rise to most of neurons and glial cells that constitute the adult central nervous system. A hallmark of RGCs is their polarization along the apical-basal axis. They extend a long basal process that contacts the pial surface and a short apical process to the ventricular surface. Adherens junctions (AJs) are organized as belt-like structures at the most-apical lateral plasma membrane of the apical processes. These junctional complexes anchor RGCs to each other and allow the recruitment of cytoplasmic proteins that act as apical-basal determinants. It has been proposed that disruption of AJs underlies the onset of different neurodevelopmental disorders. In fact, studies performed in different animal models indicate that loss of function of AJs-related proteins in NSPCs can disrupt cell polarity, imbalance proliferation and/or differentiation rates and increase cell death, which, in turn, lead to disruption of the cytoarchitecture of the ventricular zone, protrusion of non-polarized cells into the ventricles, cortical thinning, and ventriculomegaly/hydrocephalus, among other neuropathological findings. Recent Zika virus (ZIKV) outbreaks and the high comorbidity of ZIKV infection with congenital neurodevelopmental defects have led to the World Health Organization to declare a public emergency of international concern. Thus, noteworthy advances have been made in clinical and experimental ZIKV research. This review summarizes the current knowledge regarding the function of AJs in normal and pathological corticogenesis and focuses on the neuropathological and cellular mechanisms involved in congenital ZIKV syndrome, highlighting the potential role of cell-to-cell junctions between NSPCs in the etiopathogenesis of such syndrome.


Assuntos
Junções Aderentes/metabolismo , Polaridade Celular , Células-Tronco Neurais/patologia , Transtornos do Neurodesenvolvimento/patologia , Transtornos do Neurodesenvolvimento/virologia , Infecção por Zika virus/congênito , Animais , Humanos , Transtornos do Neurodesenvolvimento/epidemiologia , Síndrome
6.
Clin Sci (Lond) ; 132(24): 2583-2598, 2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30545896

RESUMO

Estrogens generated within endocrine organs and the reproductive system act as ligands for at least three types of estrogen receptors. Estrogen receptors α (ERα) and ß (ERß) belong to the so-called classical family of estrogen receptors, whereas the G protein-coupled receptor GPR30, also known as GPER-1, has been described as a novel estrogen receptor sited in the cell membrane of target cells. Furthermore, these receptors are under stimulation of a family of exogenous estrogens, known as phytoestrogens, which are a diverse group of non-steroidal plant compounds derived from plant food consumed by humans and animals. Because phytoestrogens are omnipresent in our daily diet, they are becoming increasingly important in both human health and disease. Recent evidence indicates that in addition to classical estrogen receptors, phytoestrogens also activate GPER-1 a relevant observation since GPER-1 is involved in several physiopathological disorders and especially in estrogen-dependent diseases such as breast cancer.The first estrogen receptors discovered were the classical ERα and ERß, but from an evolutionary point of view G protein-coupled receptors trace their origins in history to over a billion years ago suggesting that estrogen receptors like GPER-1 may have been the targets of choice for ancient phytoestrogens and/or estrogens.This review provides a comprehensive and systematic literature search on phytoestrogens and its relationship with classical estrogen receptors and GPER-1 including its role in breast cancer, an issue still under discussion.


Assuntos
Anticarcinógenos/administração & dosagem , Neoplasias da Mama/metabolismo , Antagonistas de Estrogênios/administração & dosagem , Glândulas Mamárias Humanas/efeitos dos fármacos , Fitoestrógenos/administração & dosagem , Receptores Acoplados a Proteínas G/agonistas , Animais , Anticarcinógenos/efeitos adversos , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/prevenção & controle , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/metabolismo , Exposição Dietética/efeitos adversos , Antagonistas de Estrogênios/efeitos adversos , Feminino , Humanos , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Fitoestrógenos/efeitos adversos , Fatores de Proteção , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Medição de Risco , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos
7.
J Acoust Soc Am ; 144(2): 1040, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30180718

RESUMO

The bias errors of transmission tube measurements are evaluated using an empty test tube condition, implying full sound transmission, normal-incidence sound transmission loss (nSTL) = 0, and two narrow tube elements presenting a theoretically known sound transmission loss (which includes modeling of thermo-viscous losses), varying in frequency around moderate non-zero nSTL levels, and approaching insulation levels more typically found in applications. Results show that the different reference conditions are virtually equivalent in presenting negligible amounts of bias error within the corresponding measurement uncertainties, typically within ±1 dB, in the full 6000 Hz measurement frequency range in this particular case. Slight differences are evident only in the upper third of this range, from 4000 to 6000 Hz, in which bias errors for the narrow tube elements are found very slightly beyond the measurement uncertainties, suggesting the existence of additional sound loss mechanisms. Measurements of a typical insulating test sample are also presented for illustration of the possible non-significance of bias errors in practical cases.

8.
J Acoust Soc Am ; 142(4): 1717, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29092571

RESUMO

A progressive spherical or spheroidal wavefront approximation has previously been found to be a necessary step for a more accurate application of Webster's wave equation to rapidly flaring horns. This leads to a necessary transformation of the horn area function, from the usual flat cross-sectional area in terms of the axial coordinate, into a curved cap-like wavefront area as a function of either the axial coordinate, the arc-length coordinate along the horn profile, the leading curved wavefront coordinate, or still other possible longitudinal coordinates. In this article, horn functions, and related frequency potential functions are calculated from the measured horn profiles of a trombone and a trumpet for several of the above parameterizations. From them, cutoff frequencies and effective lengths are determined. A comparison is drawn between theoretical results using different parameterizations, results calculated via transfer-matrix models, and experimental measurements of the acoustical input impedance and reflection function of both instruments. Results indicate that one-dimensional models accurately predict the effective lengths, and consequently the fundamental resonance frequency of the instruments within ±25 cents, but fail noticeably in predicting cutoff frequencies, leading to what is probably an inaccurate representation of perceived timbre.

9.
J Acoust Soc Am ; 141(2): 1093, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28253663

RESUMO

Current techniques for measuring normal incidence sound transmission loss with a modified impedance tube, or transmission tube, require setting up two different absorbing termination loads at the end of the downstream tube [ASTM E2611-09, Standard Test Method for Measurement of Normal Incidence Sound Transmission of Acoustical Materials Based on the Transfer Matrix Method (American Society for Testing and Materials, West Conshohocken, 2009)]. The process of physically handling the two required passive absorbing loads is a possible source of measurement errors, which are mainly due to changes in sample test position, or in test setup re-assembly, between measurements. In this paper, a modified transmission tube apparatus is proposed for non-intrusively changing the downstream acoustic load by means of a combined passive-active termination. It provides a controlled variable sound absorption which simplifies the setup of standard two-load techniques, without the need of physically handling the apparatus during the tests. This virtually eliminates the risk of errors associated with the physical manipulation of the two passive terminations. Transmission loss measurements in some representative test conditions are reported, showing improvements over current implementations, in reducing by approximately 50% the measurement variations associated with the setup of the two required absorbing terminations. Measurement results agree within 0.4 dB (maximum difference in high resolution broadband), and 0.04 dB (mean difference in 1/3-octave bands), with those obtained using standard passive two-load methods.

10.
Forensic Sci Int ; 239: e1-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24731703

RESUMO

Beetles of the genus Nitidula Fabricius are forensically important, and their adults and larvae have been found associated with human corpses and animal carcasses in many places of the world. The external morphology of the larvae of Nitidula carnaria (Schaller 1783) was examined by scanning electron microscopy (SEM) to provide a description enabling identification of this forensically important species. The ultrastructure of the head was examined, antennae, mandibles, epipharynx, maxillary and labial palpi, spiracles, thorax, legs, and abdominal segments (especially segments 9 and 10); the tegument was also emphasised in this examination. Several types of sensilla were observed on the maxillary and labial palpi, including sensilla basiconica, sensilla styloconica, and perhaps a different type of sensilla digitiformia. In abdominal segment 10, a sensilla campaniformia was observed. Two types of plates were noticed in the abdominal tegument. The characteristics described here can be used to identify this species. No other study of the ultrastructure of Nitidulidae larvae is available for comparison. This is the first report of N. carnaria in carcasses in Chile.


Assuntos
Besouros/ultraestrutura , Animais , Entomologia , Comportamento Alimentar , Patologia Legal , Larva/ultraestrutura , Microscopia Eletrônica de Varredura , Mudanças Depois da Morte , Sensilas/ultraestrutura , Suínos
11.
J Acoust Soc Am ; 127(2): 1096-103, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20136230

RESUMO

The propagation of finite-amplitude waves inside a slide trombone is studied through direct pressure measurements corresponding to dynamic extremes. A two-microphone method is used to separate left-moving and right-moving waves inside the trombone, permitting the detection of nonlinear effects associated with progressive waves. It is found that a redistribution of energy across the spectrum toward the higher-frequencies occurs for large distances and high initial pressure levels. These results are consistent with the theory of weakly nonlinear acoustics and also with those reported in this same context by other authors, but which have been obtained mostly through examination of standing-waves.

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