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Aedes aegypti and Aedes albopictus are the main vectors of arboviruses such as Dengue, Chikungunya and Zika, causing a major impact on global economic and public health. The main way to prevent these diseases is vector control, which is carried out through physical and biological methods, in addition to environmental management. Although chemical insecticides are the most effective strategy, they present some problems such as vector resistance and ecotoxicity. Recent research highlights the potential of the imidazolium salt "1-methyl-3-octadecylimidazolium chloride" (C18MImCl) as an innovative and environmentally friendly solution against Ae. aegypti. Despite its promising larvicidal activity, the mode of action of C18MImCl in mosquito cells and tissues remains unknown. This study aimed to investigate its impacts on Ae. aegypti larvae and three cell lines of Ae. aegypti and Ae. albopictus, comparing the cellular effects with those on human cells. Cell viability assays and histopathological analyses of treated larvae were conducted. Results revealed the imidazolium salt's high selectivity (> 254) for mosquito cells over human cells. After salt ingestion, the mechanism of larval death involves toxic effects on midgut cells. This research marks the first description of an imidazolium salt's action on mosquito cells and midgut tissues, showcasing its potential for the development of a selective and sustainable strategy for vector control.
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Aedes , Imidazoles , Insecticidas , Larva , Aedes/efectos de los fármacos , Animales , Larva/efectos de los fármacos , Imidazoles/toxicidad , Imidazoles/farmacología , Insecticidas/toxicidad , Insecticidas/farmacología , Humanos , Mosquitos Vectores/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Control de Mosquitos/métodosRESUMEN
BACKGROUND: The use of balanced crystalloids over normal saline for perioperative fluid management during kidney transplantation and its benefits on acid-base and electrolyte balance along with its influence on postoperative clinical outcomes remains a topic of controversy. Therefore, we conducted this review to assess the impact of balanced solutions compared to normal saline on outcomes for kidney transplant patients. METHODS: We searched MEDLINE, EMBASE, and Cochrane databases for randomized controlled trials (RCTs) comparing balanced lower-chloride solutions to normal saline in renal transplant patients. Our main outcome of interest was delayed graft function (DGF). Additionally, we examined acid-base and electrolyte measurements, along with postoperative renal function. We computed relative risk (RR) using the Mantel-Haenszel test for binary outcomes, and mean difference (MD) for continuous data, and applied DerSimonian and Laird random-effects models to address heterogeneity. Furthermore, we performed a trial sequential analysis (TSA) for all outcomes. RESULTS: Twelve RCTs comprising a total of 1668 patients were included; 832 (49.9%) were assigned to receive balanced solutions. Balanced crystalloids reduced the occurrence of DGF compared to normal saline, with RR of 0.82 (95% confidence interval [CI], 0.71-0.94), P = .005; I² = 0%. The occurrence was 25% (194 of 787) in the balanced crystalloids group and 34% (240 of 701) in the normal saline group. Moreover, our TSA supported the primary outcome result and suggests that the sample size was sufficient for our conclusion. End-of-surgery chloride (MD, -8.80 mEq·L -1 ; 95% CI, -13.98 to -3.63 mEq.L -1 ; P < .001), bicarbonate (MD, 2.12 mEq·L -1 ; 95% CI, 1.02-3.21 mEq·L -1 ; P < .001), pH (MD, 0.06; 95% CI, 0.04-0.07; P < .001), and base excess (BE) (MD, 2.41 mEq·L -1 ; 95% CI, 0.88-3.95 mEq·L -1 ; P = .002) significantly favored the balanced crystalloids groups and the end of surgery potassium (MD, -0.17 mEq·L -1 ; 95% CI, -0.36 to 0.02 mEq·L -1 ; P = .07) did not differ between groups. However, creatinine did not differ in the first (MD, -0.06 mg·dL -1 ; 95% CI, -0.38 to 0.26 mg·dL -1 ; P = .71) and seventh (MD, -0.06 mg·dL -1 ; 95% CI, -0.18 to 0.06 mg·dL -1 ; P = .30) postoperative days nor urine output in the first (MD, -1.12 L; 95% CI, -3.67 to 1.43 L; P = .39) and seventh (MD, -0.01 L; 95% CI, -0.45 to 0.42 L; P = .95) postoperative days. CONCLUSIONS: Balanced lower-chloride solutions significantly reduce the occurrence of DGF and provide an improved acid-base and electrolyte control in patients undergoing kidney transplantation.
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Soluciones Cristaloides , Fluidoterapia , Trasplante de Riñón , Solución Salina , Humanos , Soluciones Cristaloides/administración & dosificación , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/métodos , Solución Salina/administración & dosificación , Fluidoterapia/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Equilibrio Ácido-Base/efectos de los fármacos , Resultado del Tratamiento , Funcionamiento Retardado del Injerto/prevención & control , Funcionamiento Retardado del Injerto/etiología , Soluciones Isotónicas/administración & dosificaciónRESUMEN
There is an increasing need for developing a strategy to analyze the penetration of pesticides in cultures during postharvest control with minimal or no sample preparation. This study explores the combined use of laser ablation electrospray ionization mass spectrometry imaging (LAESI imaging) and tissue spray ionization mass spectrometry (TSI-MS) to investigate the penetration of thiabendazole (TBZ) in fruits, simulating a postharvest procedure. Slices of guava and apple were prepared, and an infrared laser beam was used, resulting in the ablation of TBZ directly ionized by electrospray and analyzed by mass spectrometry. The experiments were conducted for 5 days of fruit storage after TBZ administration to simulate a postharvest treatment. During postharvest treatment, TBZ is applied directly to the fruit peel after harvesting. Consequently, TBZ residues may remain on the peel if the consumer does not wash the fruit properly before its consumption. To evaluate the effectiveness of household washing procedures, TSI-MS was employed as a rapid and straightforward technique to monitor the remaining amount of TBZ in guava and apple peels following fruit washing. This study highlights the advantages of LAESI imaging for evaluating TBZ penetration in fruits. Moreover, the powerful capabilities of TSI-MS are demonstrated in monitoring and estimating TBZ residues after pesticide application, enabling the comprehensive unveiling of pesticide contaminants in fruits.
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Plaguicidas , Plaguicidas/análisis , Frutas/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Tiabendazol/análisisRESUMEN
The pandemic caused by coronavirus has resonated throughout different levels of health care in Brazil and, in this context, the present research aimed to evaluate this impact on tertiary dental care provided by the Unified Health System (SUS). Therefore, an ecological study was conducted with data obtained from the Hospital Information System processed by the Portal of the Department of Informatics of SUS. The sample consisted of patients of all sexes and age groups, whose Hospital Admission Authorizations (AIHs) were approved for dental tertiary care procedures from January 2015 to December 2020. Descriptive analyses and the ANOVA test with a significance level set at p < 0.05 were used. When the annual mean numbers of AIHs approved were evaluated, findings showed that on an average, the Southeast region authorized a higher number of procedures (p-value < 0.001), however, in the pandemic year (2020), a reduction of approximately 24.5% of these hospitalizations occurred throughout Brazil, with the Midwest being the region most affected (32.12%). A percentage increase occurred in the Surgical Treatment of Oral sinus/Oral nasal Fistula (16.1%), in addition to a significant decrease in performing procedures for Resection of Mouth Lesion (33.4%). In the pandemic year, there was a reduction of 14% in expenditures related to hospital services and 23.26% related to professional services. It was concluded that the data presented demonstrated a significant reduction in AIHs for tertiary dental care in the pandemic year.
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COVID-19 , Humanos , Pandemias , Atención Terciaria de Salud , Brasil , Atención OdontológicaRESUMEN
Abstract The pandemic caused by coronavirus has resonated throughout different levels of health care in Brazil and, in this context, the present research aimed to evaluate this impact on tertiary dental care provided by the Unified Health System (SUS). Therefore, an ecological study was conducted with data obtained from the Hospital Information System processed by the Portal of the Department of Informatics of SUS. The sample consisted of patients of all sexes and age groups, whose Hospital Admission Authorizations (AIHs) were approved for dental tertiary care procedures from January 2015 to December 2020. Descriptive analyses and the ANOVA test with a significance level set at p < 0.05 were used. When the annual mean numbers of AIHs approved were evaluated, findings showed that on an average, the Southeast region authorized a higher number of procedures (p-value < 0.001), however, in the pandemic year (2020), a reduction of approximately 24.5% of these hospitalizations occurred throughout Brazil, with the Midwest being the region most affected (32.12%). A percentage increase occurred in the Surgical Treatment of Oral sinus/Oral nasal Fistula (16.1%), in addition to a significant decrease in performing procedures for Resection of Mouth Lesion (33.4%). In the pandemic year, there was a reduction of 14% in expenditures related to hospital services and 23.26% related to professional services. It was concluded that the data presented demonstrated a significant reduction in AIHs for tertiary dental care in the pandemic year.
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Here, we present a new application of desorption electrospray ionization (DESI) and laser ablation electrospray ionization (LAESI) mass spectrometry imaging to assess the spatial location of organic compounds, both polar and nonpolar, directly from rock surfaces. Three carbonaceous rocks collected from an aquatic environment and a berea sandstone subjected to a small-scale oil recovery experiment were analyzed by DESI and LAESI. No rock pretreatment was required before DESI and LAESI analyses. DESI detected and spatially mapped several fatty acids and a disaccharide on the surfaces of carbonaceous rocks, and various nitrogenated and oxygenated compounds on the surfaces of berea sandstone. In contrast, LAESI using a 3.4 µm infrared laser beam was able to detect and map hydrocarbons on the surfaces of all rock samples. Both techniques can be combined to analyze polar and nonpolar compounds. DESI can be used first to detect polar compounds, as it does not destroy the rock surface, and LAESI can then be used to analyze nonpolar analytes, as it destroys a layer of the sample surface. Both techniques have the potential to be used in several scientific areas involving rocks and minerals, such as in the analysis of industry-derived contaminants in aquatic sediments or in small-scale rock-fluid interaction experiments.
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Terapia por Láser , Espectrometría de Masa por Ionización de Electrospray , Disacáridos , Ácidos Grasos , Hidrocarburos , Minerales , Espectrometría de Masa por Ionización de Electrospray/métodosRESUMEN
3D printing is a technology that has revolutionized traditional rapid prototyping methods due to its ability to build microscale structures with customized geometries in a simple, fast, and low-cost way. In this sense, this article describes the development of a microfluidic mixing device to monitor chemical reactions by mass spectrometry (MS). Microfluidic mixers were designed containing 3D serpentine and Y-shaped microchannels, both with a pointed end for facilitating the spray formation. The devices were fabricated entirely by 3D printing with fusion deposition modeling (FDM) technology. As proof-of-concept, micromixers were evaluated through monitoring the Katritzky reaction by injecting simultaneously 2,4,6-triphenylpropyllium (TPP) and amino acid (glycine or alanine) solutions, each through a different reactor inlet. Reaction product was monitored online by MS at different flow rates. Mass spectra showed that the relative abundances of the products obtained with the device containing the 3D serpentine channel were three times greater than those obtained with the Y-channel device due to the turbulence generated by the barriers created inside microchannels. In addition, when compared to the conventional electrospray ionization mass spectrometry (ESI-MS) technique, the 3D serpentine mixer offered better performance measured in relation to the relative abundance values for the reaction products. These results as well as the instrumental simplicity indicate that 3D printed microfluidic mixer is a promising tool for monitoring organic reactions via MS.
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Dispositivos Laboratorio en un Chip , Microfluídica , Impresión Tridimensional , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
This work describes the use of laser ablation electrospray ionization mass spectrometry imaging (LAESI imaging) to investigate the diffusion of the mycotoxin patulin from rotten to healthy areas of fruits. Slices of mold-infected and uninfected (control) apples and strawberries were prepared, and this was the only sample preparation step used. An infrared laser beam (2.94 µm) was used to irradiate the slices, resulting in the ablation of sample compounds directly ionized by electrospray and analyzed by mass spectrometry. Multivariate curve resolution - alternating least squares was applied in unfolded LAESI images to obtain relative quantity information. Patulin was not detected in the control samples but was seen in all mold-infected fruits. LAESI images showed the diffusion of patulin from the rotten area to unaffected parts of the fruits. This study points out the advantage of LAESI imaging over traditional analytical methods used to study the diffusion of mycotoxins in fruits.
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Terapia por Láser , Malus , Patulina , Frutas , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
Since the start of the COVID-19 pandemic many studies investigated the correlation between climate variables such as air quality, humidity and temperature and the lethality of COVID-19 around the world. In this work we investigate the use of climate variables, as additional features to train a data-driven multivariate forecast model to predict the short-term expected number of COVID-19 deaths in Brazilian states and major cities. The main idea is that by adding these climate features as inputs to the training of data-driven models, the predictive performance improves when compared to equivalent single input models. We use a Stacked LSTM as the network architecture for both the multivariate and univariate model. We compare both approaches by training forecast models for the COVID-19 deaths time series of the city of São Paulo. In addition, we present a previous analysis based on grouping K-means on AQI curves. The results produced will allow achieving the application of transfer learning, once a locality is eventually added to the task, regressing out using a model based on the cluster of similarities in the AQI curve. The experiments show that the best multivariate model is more skilled than the best standard data-driven univariate model that we could find, using as evaluation metrics the average fitting error, average forecast error, and the profile of the accumulated deaths for the forecast. These results show that by adding more useful features as input to a multivariate approach could further improve the quality of the prediction models.
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Contaminación del Aire , COVID-19 , Contaminación del Aire/análisis , Brasil , Humanos , Humedad , Pandemias , SARS-CoV-2 , TemperaturaRESUMEN
This work describes the surface coating of wooden toothpicks with amino groups (NH2) for electrospray ionization mass spectrometry (MS) analysis of naphthenic acids (NAs) in produced water samples and crude oil fractions. NH2 was introduced into the cellulosic material through a silanization reaction using aminopropyltriethoxysilane. An NH2-modified toothpick was inserted into the analyte extraction sample and was subsequently used as an electrospray emitter for MS analysis. The extraction conditions were optimized by analyzing NAs (benzoic acid, 1-naphthoic acid, decanoic acid, 3,5-dimethyladamantane-1-carboxylic acid, and 3,5-dimethyladamantane-1-acetic acid) in pure water, and the best condition was using 5 min of extraction time with the samples under agitation. Modified and unmodified wooden toothpicks were compared, and the intensities of all NAs were higher when using the modified substrates than when using the unmodified ones. Limit of detection (LOD), limit of quantification (LOQ), linearity, precision, and recovery were determined by analyzing decanoic acid in seawater samples. The LOD and LOQ were 2 and 5 µg mL-1, respectively, and a linear correlation (R2 = 0.9927) was obtained with concentrations ranging from 5 to 250 µg mL-1. Precision values ranged from 6 to 13% and recoveries from 89 to 106%. The technique was also employed to analyze three produced water samples, in which decanoic acid was semi-quantified, and the concentrations ranged from 10 to 13 µg mL-1. High abundances of acidic compounds of class O2 with DBEs (double bond equivalents) ranging from 1 to 3 and carbon numbers going from 8 to 12 were detected in the produced water samples. The results suggest that the modification of wooden toothpicks with NH2 might offer a significant advancement in the knowledge of cheap substrates that can improve the sensitivity of analysis of NAs in water samples.
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Petróleo , Espectrometría de Masa por Ionización de Electrospray , Ácidos Carboxílicos/análisis , Ácidos Carboxílicos/química , Espectrometría de Masa por Ionización de Electrospray/métodos , AguaRESUMEN
This work describes the development of a system that combines a derivatization protocol based on the Katritzky reaction with paper spray ionization mass spectrometry (PSI-MS) for the analysis of amino acid neurotransmitters in mouse brain tissues. The system is relatively simple, consisting of spraying the derivatization solution onto a mouse brain section mounted on a glass slide, applying a small volume of solvent to moisten the sample, pressing a triangular paper onto the sample surface to transfer the sample constituents to the paper surface, and using the paper as a substrate for PSI-MS analysis. The Katritzky reaction facilitated the ionization of the amino acids by reacting a pyrylium salt with the amino group of the analytes, forming very stable pyridinium cations, which greatly increased the sensitivity of the PSI-MS analysis. Most of the intensities of the amino acids modified by the Katritzky reaction were more than 10 times greater than the nonderivatized ones. The system was applied for the analysis of brain sections obtained from mice with Parkinson's disease, and the amino acids gamma-aminobutyric acid (GABA) and glycine (Gly), two compounds very well-known in studies of Parkinson's disease, were readily detected. The results suggest that the Katritzky reaction combined with PSI-MS might offer a significant advance in the knowledge on protocols that improve the sensitivity of detection of crucial biological compounds.
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Aminoácidos/análisis , Química Encefálica/fisiología , Neurotransmisores/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Aminoácidos/química , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Neurotransmisores/química , PapelRESUMEN
abstract - This paper is an update of the systematic review on Active Play published in 2018 by Mendes et al. This systematic review included studies published between 2018 and 2019. The search for potential articles was performed on the following electronic databases: Pubmed/Medline, Web of Science, Bireme, Scielo and Scopus. Initially, 471 papers met the eligibility criteria. However, after deeply analyzed, only two studies remained and were included in the present review. From these articles only one presented individual information on play activity among adolescents age (12-17 years) from Curitiba-PR and it reveals that 77,2% of them were physically active in their free time. The other study included was about the preferences for leisure activities among adolescents from Florianopolis-SC participants in two cross sectional studies in 2001 and 2011. It showed a significant reduction in the preferences for practicing physical activities, while the opposite occurs with sedentary activities like watching TV, playing video games, and using computers. These results along with the inconsistencies in benchmarks of the domain active play among countries involved in the Global Matrix 3.0 made clear the necessity of a standard definition and a proper tool to measure it.
resumo - Este artigo é uma atualização da revisão sistemática sobre Active Play publicada em 2018 por Mendes et al. Esta revisão sistemática incluiu estudos publicados entre 2018 até 2019. A busca de potenciais artigos foi realizada nas seguintes bases de dados eletrônicas: Pubmed / Medline, Web of Science, Bireme, Scielo e Scopus. Inicialmente, 471 artigos atenderam aos critérios de elegibilidade. Porém, após análise aprofundada, apenas dois estudos permaneceram e foram incluídos na presente revisão. Destes artigos, apenas um apresentou informações individuais sobre a atividade física entre adolescentes de 12 a 17 anos de idade de Curitiba-PR e revelou que 77,2% deles eram fisicamente ativos no tempo livre. O outro estudo foi sobre as preferências por atividades de lazer entre adolescentes de Florianópolis-SC avaliados nos anos de 2001 e 2011. Este apresentou redução significativa na preferência pela prática de atividades físicas, enquanto o contrário foi observado para atividades sedentárias, como assistir TV, jogar videogame e usar o computador. Esses resultados, juntamente com as inconsistências nos pontos de corte do domínio active play entre os países envolvidos na Matriz Global 3.0, deixaram claro a necessidade de uma definição padrão e de uma ferramenta adequada para medi-la.
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Polypyrrole (PPy) is a polymer widely used as an extraction phase due to its ability to perform intermolecular interactions with the analyte, such as acid-base, π-π, dipole-dipole, hydrophobic, and hydrogen bonding. In this manuscript, we report the coating of a stainless steel needle with a PPy film for analyte extraction and subsequent analysis by electrospray ionization mass spectrometry (ESI-MS) under ambient and open-air conditions. The method, named PPy-ESI-MS, was optimized for analysis of 3,4-methylenedioxyamphetamine (MDA) and 3,4-methylenedioxymethamphetamine (MDMA) in synthetic urine. Seven cycles of electrodeposition of the PPy film onto the needle surface, sample at pH 8, and 40 min of extraction of analytes were determined as the best analysis conditions. The analytical performance of PPy-ESI-MS was evaluated for MDA and MDMA compounds. Analytical curves were obtained with R2 > 0.98. Limits of detection (LODs) and limits of quantification (LOQs) were determined as 20 µg L-1 and 70 µg L-1 for MDA and as 25 µg L-1 and 80 µg L-1 for MDMA, respectively. Values of precision were below 17%, and values of accuracy below 5%. The apparent recoveries ranged between 84.5% and 111.3%. In addition, the PPy-ESI-MS method was applied for the analysis of sarcosine in synthetic urine in order to evaluate the performance of the method for another class of compounds. The calibration curve was obtained with R2 > 0.98, along with LOD and LOQ of 30 µg L-1 and 100 µg L-1, respectively. The precision and accuracy values were below 5% and 8%, respectively, and the apparent recoveries close to 100%. This work demonstrates the usefulness of combining an extraction phase with ESI-MS analysis under ambient conditions to determine different classes of small molecules in a complex sample.
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A new approach using paper spray ionization mass spectrometry (PSI-MS) for the analysis of steroid hormones in wastewater samples has been demonstrated. Triangular papers containing paraffin barriers as microfluidic channels were used to direct the sample solution to the paper tip, preventing the sample from spreading over the corners of the paper. The method was used to analyze the hormones levonorgestrel and algestone acetophenide in industrial wastewaters. Analytical curves presented a correlation coefficient (R2) above 0.99. Limits of quantification were below 2.3 ppm and limits of detection below 0.7 ppm. Values of precision (coefficient of variation) and accuracy (relative error) were less than 15% for all analyses. Recovery results ranged from 82% to 102%. Levonorgestrel was also analyzed by high-performance liquid chromatography coupled to mass spectrometry in order to compare the analytical performance with PSI-MS. No statistically significant differences were found between both methods. This study demonstrates the usefulness of PSI-MS for rapid analysis of hormones in industrial wastewater samples and also indicates its potential to be employed as a simple and reliable analytical method in environmental sciences.
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Hormonas/análisis , Espectrometría de Masa por Ionización de Electrospray/instrumentación , Esteroides/análisis , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis , Cromatografía Líquida de Alta Presión/instrumentación , Diseño de Equipo , Levonorgestrel/análisis , Límite de Detección , PapelRESUMEN
The contribution of this paper is twofold. First, a new data driven approach for predicting the Covid-19 pandemic dynamics is introduced. The second contribution consists in reporting and discussing the results that were obtained with this approach for the Brazilian states, with predictions starting as of 4 May 2020. As a preliminary study, we first used an Long Short Term Memory for Data Training-SAE (LSTM-SAE) network model. Although this first approach led to somewhat disappointing results, it served as a good baseline for testing other ANN types. Subsequently, in order to identify relevant countries and regions to be used for training ANN models, we conduct a clustering of the world's regions where the pandemic is at an advanced stage. This clustering is based on manually engineered features representing a country's response to the early spread of the pandemic, and the different clusters obtained are used to select the relevant countries for training the models. The final models retained are Modified Auto-Encoder networks, that are trained on these clusters and learn to predict future data for Brazilian states. These predictions are used to estimate important statistics about the disease, such as peaks and number of confirmed cases. Finally, curve fitting is carried out to find the distribution that best fits the outputs of the MAE, and to refine the estimates of the peaks of the pandemic. Predicted numbers reach a total of more than one million infected Brazilians, distributed among the different states, with São Paulo leading with about 150 thousand confirmed cases predicted. The results indicate that the pandemic is still growing in Brazil, with most states peaks of infection estimated in the second half of May 2020. The estimated end of the pandemics (97% of cases reaching an outcome) spread between June and the end of August 2020, depending on the states.
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Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Brasil/epidemiología , COVID-19 , Infecciones por Coronavirus/virología , Predicción , Humanos , Pandemias , Neumonía Viral/virología , SARS-CoV-2RESUMEN
Squamous intraepithelial lesion is an abnormal growth of epithelial cells on the surface of the cervix that may lead to cervical cancer. Analytical protocols for the determination of squamous intraepithelial lesions are in high demand, since cervical cancer is the fourth most diagnosed cancer among women in the world. Here, paper spray ionization mass spectrometry (PSI-MS) is used to distinguish between healthy (negative for intraepithelial lesion or malignancy) and diseased (high-grade squamous intraepithelial lesion) blood plasmas. A total of 86 blood samples of different women (49 healthy samples, 37 diseased samples) were collected, and the plasmas were prepared. Then, 10 µL of each plasma sample was deposited onto triangular papers for PSI-MS analysis. No additional step of sample preparation was necessary. The interval-successive projection algorithm linear discriminant analysis (iSPA-LDA) was applied to the PSI mass spectra, showing six ions (mostly phospholipids) that were predictive of healthy and diseased plasmas. Values of 77% accuracy, 86% sensitivity, 80% positive predictive value (PPV), and 75% negative predictive value (NPV) were achieved. This study provides evidence that PSI-MS may potentially be used as a fast and simple analytical technique for the early diagnosis of cervical cancer.
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A method named imprint paper spray ionization mass spectrometry (imprint-PSI-MS) has been developed and employed for the determination of pungency of peppers. A pepper fruit was cut into a triangular shape, deposited onto a triangular paper, and compressed by a homemade press tool aiming to imprint and transfer the pepper constituents onto the paper surface. Subsequently, the triangular paper was submitted to conventional PSI-MS analysis. Twelve peppers were analyzed, ranging from highly pungent to lowly pungent taste. Pepper pungency values from the Scoville scale (in Scoville heat units, SHU) were compared with the ion intensities of the capsaicin and dihydrocapsaicin compounds obtained from the imprint-PSI-MS analysis, and a correlation coefficient of 0.97 was achieved. In addition, the ion intensities of a sugar compound were monitored in all peppers, and the results were compared with the Scoville scale. Low sugar ion intensities were detected in pungent peppers, while high ion intensities were achieved in low-pungent peppers, suggesting that the pepper pungency may be determined by inversely relating pungency to sugar contents. This work demonstrates the utility of the imprint-PSI-MS method to perform rapid qualitative analyses of peppers and estimate the pungency by monitoring the pepper metabolites. Graphical abstract.