16 research outputs found
Estimation of intracranial pressure by ultrasound of the optic nerve sheath in an animal model of intracranial hypertension
Antecedentes: La ecografía del diámetro de la vaina del nervio óptico (ONSD) se ha utilizado como alternativa no invasiva y rentable a la monitorización invasiva de la presión intracraneal (PIC). Sin embargo, aún se desconoce el comportamiento temporal del ONSD en la hipertensión intracraneal (HIC) y su alivio mediante infusión salina o cirugía. El objetivo de este estudio fue correlacionar la presión intracraneal (PIC) y la ultrasonografía de la vaina del nervio óptico (ONS) en un modelo animal experimental de HIC y determinar el intervalo necesario para que la ONSD vuelva a los niveles basales. Métodos: Se realizó un estudio experimental en 30 cerdos. La ONSD se evaluó mediante ecografía a diferentes PIC generadas por inflado intracraneal con balón, infusión salina y desinflado con balón, y se midió utilizando un catéter intraventricular. Resultados: Todas las variables obtenidas por ultrasonografía ONS como ONSD izquierdo, derecho y promedio (AON) fueron estadísticamente significativas para estimar el valor de la PIC. La ONSD cambió inmediatamente después del inflado del balón y volvió a los valores basales tras un retraso medio de 30 min después del desinflado del balón (p = 0,016). No se observó significación estadística en los valores de PIC y ONSD con la infusión de solución salina hipertónica. En este modelo porcino, la PIC y la ONSD mostraron una correlación lineal y la PIC pudo estimarse mediante la fórmula: -80,5 + 238,2 × AON. Conclusiones: En el presente estudio, la ecografía para medir la ONSD mostró una correlación lineal con la PIC, aunque se observó un breve retraso en volver a los niveles basales en el caso de alivio súbito de la HIC.Background: Ultrasound of the optic nerve sheath diameter (ONSD) has been used as a non-invasive and cost-effective bedside alternative to invasive intracranial pressure (ICP) monitoring. However, ONSD time-lapse behavior in intracranial hypertension (ICH) and its relief by means of either saline infusion or surgery are still unknown. The objective of this study was to correlate intracranial pressure (ICP) and ultrasonography of the optic nerve sheath (ONS) in an experimental animal model of ICH and determine the interval needed for ONSD to return to baseline levels. Methods: An experimental study was conducted on 30 pigs. ONSD was evaluated by ultrasound at different ICPs generated by intracranial balloon inflation, saline infusion, and balloon deflation, and measured using an intraventricular catheter. Results: All variables obtained by ONS ultrasonography such as left, right, and average ONSD (AON) were statistically significant to estimate the ICP value. ONSD changed immediately after balloon inflation and returned to baseline after an average delay of 30 min after balloon deflation (p = 0.016). No statistical significance was observed in the ICP and ONSD values with hypertonic saline infusion. In this swine model, ICP and ONSD showed linear correlation and ICP could be estimated using the formula: −80.5 + 238.2 × AON. Conclusion: In the present study, ultrasound to measure ONSD showed a linear correlation with ICP, although a short delay in returning to baseline levels was observed in the case of sudden ICH relief
COVID-19 outcomes in people living with HIV: Peering through the waves
Objective: To evaluate clinical characteristics and outcomes of COVID-19 patients infected with HIV, and to compare with a paired sample without HIV infection.
Methods: This is a substudy of a Brazilian multicentric cohort that comprised two periods (2020 and 2021). Data was obtained through the retrospective review of medical records. Primary outcomes were admission to the intensive care unit, invasive mechanical ventilation, and death. Patients with HIV and controls were matched for age, sex, number of comorbidities, and hospital of origin using the technique of propensity score matching (up to 4:1). They were compared using the Chi-Square or Fisher's Exact tests for categorical variables and the Wilcoxon for numerical variables.
Results: Throughout the study, 17,101 COVID-19 patients were hospitalized, and 130 (0.76%) of those were infected with HIV. The median age was 54 (IQR: 43.0;64.0) years in 2020 and 53 (IQR: 46.0;63.5) years in 2021, with a predominance of females in both periods. People Living with HIV (PLHIV) and their controls showed similar prevalence for admission to the ICU and invasive mechanical ventilation requirement in the two periods, with no significant differences. In 2020, in-hospital mortality was higher in the PLHIV compared to the controls (27.9% vs. 17.7%; p = 0.049), but there was no difference in mortality between groups in 2021 (25.0% vs. 25.1%; p > 0.999).
Conclusions: Our results reiterate that PLHIV were at higher risk of COVID-19 mortality in the early stages of the pandemic, however, this finding did not sustain in 2021, when the mortality rate is similar to the control group
Gender Differences in COVID-19 Among Liver Transplant Recipients: Results from a Multicenter Brazilian Cohort
Introduction: Existing literature presents varying perspectives on the impact of COVID-19 on liver transplant recipients.However, no research has specifically investigated the role of gender differences in the manifestation of COVID-19 among liver transplant recipients. This study aims to examine the effects of COVID-19 on liver transplant recipients, with a focus on gender differences in disease presentation and progression. Methods: Conducted as a multicenter historical cohort study, this research collected patient records through an online questionnaire. Assessing COVID-related mortality was the main objective. Additionally, demographic, clinical, and laboratory data pertaining to disease presentation and progression werecollected. Results: The study included a total of 283 patients, of whom 76 were female and 206 were male. The median follow-up period for males was 99 days (IQR 38-283), while for females, it was 126 days (IQR 44-291). A higher prevalence of cardiovascular disease was observed in males (p=0.002). Females frequently experienced a loss of smell (p=0.021), whereas males commonly exhibited fever (p=0.031). Levels of ALT and gamma-glutamyl transferase were significantly elevated in males (p=0.008 and 0.004, respectively). Although there was a trend towards increased mortality in males, it did not reach statistical significance. Conclusion: This study is the first attempt to investigate gender differences in COVID-19 among liver transplant recipients. Our findings highlight the need for a comprehensive and personalised approach to treating this patient population and underscore the importance of further elucidating the disease presentation in these individuals
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4
While the increasing availability of global databases on ecological communities has advanced our knowledge
of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In
the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of
Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus
crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced
environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian
Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by
2050. This means that unless we take immediate action, we will not be able to establish their current status,
much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
Obstructive sleep apnea screening in different age groups: performance of the Berlin, STOP-Bang questionnaires and Epworth Sleepiness Scale
Objective: To evaluate the performance of the Berlin Questionnaire, the STOP-Bang Questionnaire, and the Epworth Sleepiness Scale in screening for the disease in adults of different age groups by comparing them with polysomnography. Methods: Cross-sectional study with prospective patient allocation, in which individuals underwent a medical interview, completion of the three screening instruments, and polysomnography. Individuals were categorized into three age groups: 18–39, 40–59, and ≥60 years. The results of the screening instruments were compared to the diagnostic criteria of the International Classification of Sleep Disorders—third edition. Performance was assessed using 2 × 2 contingency tables, estimating sensitivity, specificity, predictive value, likelihood ratio, and accuracy. Receiver Operating Characteristic curves were also constructed and the area under the curve was estimated for each instrument by age group. Results: We obtained a sample with 321 individuals suitable for analysis. The mean age was 50 years, with a predominance of females (56%). The prevalence of the disease in the overall sample was 79%, more prevalent in males in any age group and more frequent in the middle age group. The analyzes revealed that STOP-Bang performed better, both for the overall sample and for all age groups, followed by Berlin Questionnaire and Epworth Sleepiness Scale. Conclusion: In an outpatient setting with individuals with characteristics similar to those in this study, it seems sensible to choose the STOP-Bang as a screening tool for the disease, regardless of age group. Level of evidence according the guide for authors: level 2
Hormonal Receptors in Skeletal Muscles of Dystrophic Mdx Mice
Introduction. Several evidences show that muscles have an endocrine function. Glucocorticoid, estrogen, progesterone, and testosterone receptors have already been found in normal skeletal muscles, but not in dystrophic muscles. Methods. the gene expression of hormone receptors was compared between dystrophic and healthy muscles in mdx and C57BL6 mice strains. Results. the mdx mice showed a significant increase in the steroid receptors mRNA when compared to the C57BL6 mice: levels of androgen(s) receptors in the heart, estrogen receptors alpha in the EDL, and estrogen receptors beta in the quadriceps were increased. in addition, significant lowered levels of some other hormone receptors were found: corticosteroid receptors in the EDL and estrogen receptors alpha in the quadriceps. Conclusion. Dystrophic muscles bear significant differences in the expression of hormone receptors when compared to the C57BL6 mice strain. the importance of such differences is yet to be better understood
Nuclear magnetic resonance to characterize the pore system of coquinas from morro do chaves formation, sergipe-alagoas basin, Brazil
Nuclear magnetic resonance (NMR) is a recognized petrophysical tool in the oil and gas industry to characterize reservoir rocks and fluids. In this study, the pore system of coquinas from a single bed of a quarry in the Morro do Chaves Formation was evaluated. These sedimentary rocks have been considered as a potential analogous to some Brazilian pre-salt reservoir rocks. The objective of this work was to characterize the porous system of coquinas in terms of total porosity and pore size distribution using low-field NMR. Conversion of T2 relaxation times to pore size radii was performed and literature cut-offs were applied for porosity partitioning. Coquinas were classified and ranked according to their percentage of macro, meso and micro porosity. This work verified quantitatively the pore system heterogeneities for the coquina samples and the variation in the layer from which they were extracted. The study provides some clues on lateral porosity and pore size variation in any reservoir for which this unit is an analogue.Ressonância magnética nuclear (RMN) é uma técnica petrofísica reconhecida na indústria de óleo e gás pela sua capacidade de caracterizar rochas reservatório e seus fluidos saturantes. Neste estudo, foi avaliado o sistema poroso de coquinas pertencentes à uma camada de uma pedreira na Formação Morro do Chaves. Essas rochas sedimentares foram consideradas possíveis análogos de algumas rochas carbonáticas do pré-sal brasileiro. O objetivo do trabalho foi caracterizar o sistema poroso dessas coquinas em termos de porosidade total e distribuição de tamanho de poros utilizando RMN de baixo campo. Realizou-se a conversão dos tempos de relaxação T2 para raios de poro e empregou-se cut-offs da literatura para o particionamento da porosidade. As coquinas foram classificadas e ranqueadas de acordo com a sua porcentagem de macro, meso e micro poros. Verificou-se quantitativamente a heterogeneidade do sistema poroso das coquinas estudadas e a variação da camada sedimentar em que os plugues foram retirados. O estudo fornece informações sobre a variação lateral de porosidade e tamanho de poros para reservatórios que tenham a unidade estudada como análogo
Trichobius longipes (Diptera, Streblidae) as a parasite of Phyllostomus hastatus(Chiroptera, Phyllostomidae)
Among the factors that influence the diversity of ectoparasites on bat hosts are the kind of roost and the host's social behavior. Other factors such as sex, reproductive condition and host size may influence the distribution and abundance of ectoparasites. The aim of the present study was to analyze the variation in Streblidae ectoparasites on the bat Phyllostomus hastatus, according to sex and roost type. We caught bats in four houses on Marambaia Island, municipality of Mangaratiba, and in one house at the Federal Rural University of Rio de Janeiro, municipality of Seropédica. We caught 65 females and 50 males of P. hastatus and 664 streblids of four species: Aspidoptera phyllostomatis, Strebla consocia, Trichobius“dugesii” complex and Trichobius longipes. The species T. longipes accounted for more than 99% of all the ectoparasites caught. Female bats were more parasitized than males, in terms of both prevalence and average intensity. The total number of parasites did not vary between resident and non-resident bats. The relationship between the number of individuals of T. longipes and sex and roost type was significant for resident bats. The total number of parasites on males did not differ between bachelor roosts and mixed-sex roosts. The differences found between roosts reflected the differences between the sexes