O Valor dos Indices Plaquetários na Púrpura Trombocitopénica Imune e Leucémia Linfo e Mieloblástica Aguda. Bases Clínico-Laboratoriais no Contributo para o Diagnóstico Diferencial Entre Estas Duas Patologias

Os autores apresentam um trabalho onde se pretende avaliar a utilidade dos índices plaquetários — volume plaquetário médio (VPM) e o coeficiente de variação do diâmetro plaquetário (CVDP ou PDW = Platelet Distribution Width) — e do número de plaquetas (PLAQ) no diagnóstico diferencial da trombocitopénia na púrpura trombocitopénica aguda (PTI) e na leucémia linfoblástica ou mieloblástica aguda (LLAULMA). Do mesmo modo, estudam comparativamente os dados clínicos e laboratoriais nestes dois grupos de doentes. Caracterizam 59 casos de doentes em idade pediátrica com PTI e 19 casos com LLA/LMA, seguidos na Unidade de Hematologia Infantil do Hospital de Dona Estefânia. Concluem não existir diferenças significativas entre as variáveis VPM e PDW entre os dois grupos de doentes. Com base nas três variáveis (VPM, PDW, PLAQ) foi construída uma regra de discriminação que fornece uma boa separação entre os grupos. Da caracterização clínico-laboratorial ressaltaram diferenças significativas entre as duas entidades nosológicas, o que permitiria prescindir a realização do mielograma para exclusão do diagnóstico de LLA/LMA numa criança com trombocitopénia significativa isolada

Osteoporose em poedeiras comerciais em diferentes fases de postura

O presente estudo descreve a ocorrência de osteoporose por reabsorção em poedeiras comerciais em diferentes fases de postura no Estado de Minas Gerais, Brasil. As aves acometidas tinham 23, 31 e 46 semanas de idade, estavam em decúbito e posicionadas com os membros estendidos lateralmente ou anteriormente. Imediatamente após a eutanásia foi realizada necropsia, e amostras de vários órgãos foram coletadas para exame histopatológico. Ao exame macroscópico observaram-se alterações similares em todas as aves, porém mais intensas nas aves de 23 semanas, as quais apresentaram todos os ossos facilmente quebráveis e alguns com fraturas associadas à hemorragia na musculatura adjacente. Além disso, a espessura da cortical apresentava-se moderadamente a intensamente diminuída e a cavidade medular ampliada. Ao exame histopatológico observou-se diminuição da espessura cortical dos ossos longos, e do número de trabéculas ósseas, além do adelgaçamento das remanescentes devido à extensa reabsorção óssea. A ocorrência de osteoporose em poedeiras comerciais possui uma complexidade de fatores. O alojamento em gaiolas com movimentação limitada e fatores nutricionais podem ter contribuído para a osteopenia apresentada pelas aves deste estudo. Causas nutricionais (minerais que atuam na maior formação de osso medular e cortical no período pré-postura) e não nutricionais (restrição a locomoção e genética) que determinam o desenvolvimento da osteoporose em aves poedeiras devem ser compreendidos para efetuar a prevenção e o controle dessa condição

Cosmic ray short burst observed with the Global Muon Detector Network (GMDN) on June 22, 2015

We analyze the short cosmic ray intensity increase ("cosmic ray burst": CRB) on June 22, 2015 utilizing a global network of muon detectors and derive the global anisotropy of cosmic ray intensity and the density (i.e. the omnidirectional intensity) with 10-minute time resolution. We find that the CRB was caused by a local density maximum and an enhanced anisotropy of cosmic rays both of which appeared in association with Earth's crossing of the heliospheric current sheet (HCS). This enhanced anisotropy was normal to the HCS and consistent with a diamagnetic drift arising from the spatial gradient of cosmic ray density, which indicates that cosmic rays were drifting along the HCS from the north of Earth. We also find a significant anisotropy along the HCS, lasting a few hours after the HCS crossing, indicating that cosmic rays penetrated into the inner heliosphere along the HCS. Based on the latest geomagnetic field model, we quantitatively evaluate the reduction of the geomagnetic cut-off rigidity and the variation of the asymptotic viewing direction of cosmic rays due to a major geomagnetic storm which occurred during the CRB and conclude that the CRB is not caused by the geomagnetic storm, but by a rapid change in the cosmic ray anisotropy and density outside the magnetosphere.Comment: accepted for the publication in the Astrophysical Journa

Determination of the total acid number (TAN) of used mineral oils in aviation engines by FTIR using regression models

[EN] Total acid number (TAN) has been considered an important indicator of the oil quality of used oils. TAN is determined by potentiometric titration, which is time-consuming and requires solvent. A more convenient approach to determine TAN is based on infrared (IR) spectral data and multivariate regression models. Predictive models for the determination of TAN using the IR data measured from ashless dispersant oils developed for aviation piston engines (SAE 50) have been developed. Different techniques, including Projection Pursuit Regression (PPR), Partial Least Square, Support Vector Machines, Linear Models and Random Forest (RF), have been used. The used methodology involved a five folder cross validation to derive the best model. Then a full error measure over the whole dataset was taken. A backward variable selection was used and 25 highly relevant variables were extracted. RF provided an acceptable modelling technology with grouped dataset predictions that allowed transformations to be performed that fitted the measured values. A hybrid method considering group of bands as features was used for modelling. An innovative mechanism for wider features selection based on genetic algorithm has been implemented. This method showed better performance than the results obtained using the other methodologies. RMSE and MAE values obtained in the validation were 0.759 and 0.359 for PPR model respectively.The authors would like to thank Roland Tones of the Universidad Metropolitana for his collaboration in oil sample processing. BLDR acknowledges financial support from the Venoco Company. The authors also thank the Universidad Politecnica de Madrid for granting access to the CESVIMA (http://www.cesvima.upm.es/) HPC infrastructure. We would also like to thank the author Beatriz Leal de Rivas (in memoriam), for her efforts to conform this team of researchers from different areas of expertise, and we want to dedicate this work to her loving memory.Leal De-Rivas, BC.; Vivancos, J.; Ordieres Meré, J.; Capuz-Rizo, SF. (2017). Determination of the total acid number (TAN) of used mineral oils in aviation engines by FTIR using regression models. Chemometrics and Intelligent Laboratory Systems. 160:32-39. doi:10.1016/j.chemolab.2016.10.015S323916

Help-Seeking Behavior during Elevated Temperature in Chinese Population

The negative impact of extreme temperatures on health is well-established. Individual help-seeking behavior, however, may mitigate the extent of morbidity and mortality during elevated temperatures. This study examines individual help-seeking behavior during periods of elevated temperatures among a Chinese population. Help-seeking patterns and factors that influence behavior will be identified so that vulnerable subgroups may be targeted for health protection during heat crises. A retrospective time-series Poisson generalized additive model analysis, using meteorological data of Hong Kong Observatory and routine emergency help call data from The Hong Kong Senior Citizen Home Safety Association during warm seasons (June–September) 1998–2007, was conducted. A “U”-shaped association was found between daily emergency calls and daily temperature. About 49% of calls were for explicit health-related reasons including dizziness, shortness of breath, and general pain. The associate with maximum temperature was statistically significant (p = 0.034) with the threshold temperature at which the frequency of health-related calls started to increase being around 30–32°C. Mean daily relative humidity (RH) also had a significant U-shaped association with daily emergency health-related calls with call frequency beginning to increase with RH greater than 70–74% (10–25% of the RH distribution). Call frequency among females appeared to be more sensitive to high temperatures, with a threshold between 28.5°C and 30.5°C while calls among males were more sensitive to cold temperatures (threshold 31.5–33.5°C). Results indicate differences in community help-seeking behavior at elevated temperatures. Potential programs or community outreach services might be developed to protect vulnerable subgroups from the adverse impact of elevated temperatures

Prognostic value of neutrophil-to-lymphocyte ratio in COVID-19 patients: A systematic review and meta-analysis

Background: Neutrophil-to-lymphocyte ratio (NLR) is an accessible and widely used biomarker. NLR may be used as an early marker of poor prognosis in patients with COVID-19. Objective: To evaluate the prognostic value of the NLR in patients diagnosed with COVID-19. Methods: We conducted a systematic review and meta-analysis. Observational studies that reported the association between baseline NLR values (ie, at hospital admission) and severity or all-cause mortality in COVID-19 patients were included. The quality of the studies was assessed using the Newcastle-Ottawa Scale (NOS). Random effects models and inverse variance method were used for meta-analyses. The effects were expressed as odds ratios (ORs) and their 95% confidence intervals (CIs). Small study effects were assessed with the Egger's test. Results: We analysed 61 studies (n = 15 522 patients), 58 cohorts, and 3 case-control studies. An increase of one unit of NLR was associated with higher odds of severity (OR 6.22; 95%CI 4.93 to 7.84; P <.001) and higher odds of all-cause mortality (OR 12.6; 95%CI 6.88 to 23.06; P <.001). In our sensitivity analysis, we found that 41 studies with low risk of bias and moderate heterogeneity (I2 = 53% and 58%) maintained strong association between NLR values and both outcomes (severity: OR 5.36; 95% CI 4.45 to 6.45; P <.001; mortality: OR 10.42 95% CI 7.73 to 14.06; P =.005). Conclusions: Higher values of NLR were associated with severity and all-cause mortality in hospitalised COVID-19 patients.Revisión por pare

Vitamin B12 levels in thyroid disorders: A systematic review and meta-analysis

Background and aims: Numerous studies have found an association between vitamin deficiency and thyroid disorders (TD). The presence of anti-parietal cell antibodies is indicative of reduced ability to absorb vitamin B12. Thus, this study reviewed the existing studies with the objective of assessing differences in the serum levels of vitamin B12 among patients with and without TD, the frequency of vitamin B12 deficiency in patients with TD, and the presence of anti-parietal cell antibodies in patients with TD. Methods: A meta-analysis of random-effects model was conducted to calculate pooled frequencies, mean differences (MD), and their respective 95% confidence intervals (CI). We identified 64 studies that met our inclusion criteria (n = 28597). Results: We found that patients with hypothyroidism had lower vitamin B12 levels than healthy participants (MD: −60.67 pg/mL; 95% CI: −107.31 to −14.03 pg/mL; p = 0.01). No significant differences in vitamin B12 levels were observed between healthy participants and patients with hyperthyroidism (p = 0.78), autoimmune thyroid disease (AITD) (p = 0.22), or subclinical hypothyroidism (SH) (p = 0.79). The frequencies of vitamin B12 deficiency among patients with hypothyroidism, hyperthyroidism, SH, and AITD were 27%, 6%, 27%, and 18%, respectively. Conclusions: Patients with hypothyroidism had lower levels of vitamin B12 than healthy participants. No significant differences were observed between vitamin B12 levels and hyperthyroidism, AITD, or SH. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=324422, identifier (CRD42022324422)