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1.
Emerg Radiol ; 30(2): 197-202, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36913060

RESUMEN

PURPOSE: Ordering trends for computed tomographic pulmonary angiogram (CTPA) studies by local emergency departments were assessed, along with the impact of the COVID-19 pandemic on these ordering trends and CTPA positivity rates. METHODS: A retrospective quantitative analysis was performed on all CTPA studies ordered between February 2018 - January 2022 by three local tertiary care emergency rooms to investigate for pulmonary embolism. Data collected from the first two years of the COVID-19 pandemic was compared to the two years prior to the pandemic to assess for significant changes in ordering trends and positivity rates. RESULTS: The overall number of CTPA studies ordered increased from 534 studies in 2018-2019 to 657 in 2021-2022 and the rate of positive diagnosis of acute pulmonary embolism varied between 15.8% to 19.5% over the four years studied. There was no statistically significant difference in the number of CTPA studies ordered when comparing the first two years of the COVID-19 pandemic to the two years immediately prior; however, the positivity rate was significantly higher during the first two years of the pandemic. CONCLUSION: Over the studied period from 2018-2022, the overall number of CTPA studies ordered by local emergency departments has increased, in line with literature reports from other locations. There was also a correlation between the onset of the COVID-19 pandemic and CTPA positivity rates, possibly secondary to the prothrombotic nature of this infection or the increase in sedentary lifestyles during lockdown periods.


Asunto(s)
COVID-19 , Embolia Pulmonar , Humanos , Estudios Retrospectivos , Pandemias , Control de Enfermedades Transmisibles , Angiografía por Tomografía Computarizada/métodos , Servicio de Urgencia en Hospital
2.
Artículo en Inglés | MEDLINE | ID: mdl-25546055

RESUMEN

Sex differentiation in organisms is correlated to sex steroid production and receptor signaling pathways involving androgens and estrogens. Timing of expression is critical, and characterization of sensitive windows is needed to determine how environmental stressors may perturb sex differentiation. The objectives of this study were to determine whether genes related to steroid biosynthesis, steroid receptor signaling, and those related to sex differentiation were expressed in pre-differentiated fathead minnow (FHM) embryos, an ecotoxicological model. Transcripts were measured over two weeks (1 day post fertilization (dpf) to 14 days), prior to sex differentiation. The first three time points investigated (1, 3, and 5 dpf) corresponded to the neurula stage, dorsal swim bladder pigmentation, and pre-hatch. The fourth time point (6 dpf) was collected immediately post-hatch and the fifth time point investigated was after 8 days of larval growth (14 dpf). The majority of transcripts investigated, for example estrogen, androgen, and thyroid receptors as well as steroid biosynthesis transcripts, were expressed within the first 72 hours of development; exceptions were star (steroidogenic acute regulatory protein) and cyp19a, which did not have detectable expression until 5 dpf (pre-hatch). Transcripts that increased in relative mRNA abundance over the first two weeks of development included ar, dax1, hsd11b2, hsd17b, cyp19a and thra. This study demonstrates that there is early expression of transcripts related to steroid biosynthesis, steroid receptor signaling, and sex differentiation in pre-hatch FHM embryos. Additional studies are required to determine their relative roles in male and female differentiation during these early developmental periods.


Asunto(s)
Cyprinidae/metabolismo , ARN Mensajero/metabolismo , Receptores de Esteroides/metabolismo , Transducción de Señal , Esteroides/metabolismo , Animales , Cyprinidae/embriología , Diferenciación Sexual , Esteroides/biosíntesis
3.
Artículo en Inglés | MEDLINE | ID: mdl-23672824

RESUMEN

γ-Amino-butyric acid (GABA) is the major inhibitory neurotransmitter in the vertebrate central nervous system. GABA receptors and synthesizing enzymes have also been localized to peripheral tissues including the liver, oviduct, uterus and ovary of mammals but the distribution and role of GABA in peripheral tissues of fish has not been fully investigated. The objectives of this study were to (1) determine if mRNA encoding GABA synthesizing enzymes (glutamic acid decarboxylase 65 and 67; gad65 and gad67), GABA transporters, and GABAA receptor subunits are localized to liver and gonad of fathead minnow (Pimephales promelas) (FHM) (2) investigate the effects of GABA on ovarian 17ß-estradiol (E2) production, and (3) measure transcript responses in the ovary after in vitro incubation to GABA. Real-time PCR assays were developed for gad65, gad67, vesicular GABA transporter (vgat) and GABA transporter 1 (gat1), and select GABAA receptor subunits (gabra1, gabra5, gabrb1, gabrb2, gabrg1, gabrg2). All transcripts were localized to the brain as expected; however transcripts were also detected in the liver, ovary, and testis of FHMs. In the female liver, gad65 mRNA was significantly higher in expression compared to the male liver. Transcripts for gad67 were the highest in the brain>gonad>liver and in the gonads, gad67 was significantly higher in expression than gad65 mRNA. In the liver and gonad, the relative abundance of the subunits followed a general trend of gabrb1>gabrb2=gabrg1=gabrg2>gabra1=gabra5. To explore the effects of GABA in the ovary, tissue explants from reproductive female FHMs were treated with GABA (10(-10), 10(-8) and 10(-6)M) for 12h. GABA had no significant effect on 17ß-estradiol production or on mRNA abundance for genes involved in ovarian steroidogenesis (e.g., 11ßhsd, cyp17, cyp19a). There was a significant decrease in estrogen receptor 2a (esr2a) mRNA with 10(-10)M GABA. This study begins to investigate the GABA system in non-neural tissues of teleost fish and addresses the broader topic regarding the peripheral roles of neurotransmitters.


Asunto(s)
Cyprinidae/metabolismo , Gónadas/metabolismo , Hígado/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Subunidades de Proteína/metabolismo , Receptores de GABA/metabolismo , Animales , Estradiol/metabolismo , Femenino , Glutamato Descarboxilasa/metabolismo , Gónadas/enzimología , Hígado/enzimología , Masculino , Mamíferos/metabolismo , Proteínas de Transporte de Membrana/genética , Ovario/citología , Ovario/enzimología , Subunidades de Proteína/genética , Receptores de GABA/genética , Testículo/metabolismo
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