RESUMO
Maize (Zea mays L.) is of socioeconomic importance as an essential food for human and animal nutrition. However, cereals are susceptible to attack by mycotoxin-producing fungi, which can damage health. The methods most commonly used to detect and quantify mycotoxins are expensive and time-consuming. Therefore, alternative non-destructive methods are required urgently. The present study aimed to use near-infrared spectroscopy with hyperspectral imaging (NIR-HSI) and multivariate image analysis to develop a rapid and accurate method for quantifying fumonisins in whole grains of six naturally contaminated maize cultivars. Fifty-eight samples, each containing 40 grains, were subjected to NIR-HSI. These were subsequently divided into calibration (38 samples) and prediction sets (20 samples) based on the multispectral data obtained. The averaged spectra were subjected to various pre-processing techniques (standard normal variate (SNV), first derivative, or second derivative). The most effective pre-treatment performed on the spectra was SNV. Partial least squares (PLS) models were developed to quantify the fumonisin content. The final model presented a correlation coefficient (R2) of 0.98 and root mean square error of calibration (RMSEC) of 508 µg.kg-1 for the calibration set, an R2 of 0.95 and root mean square error of prediction (RMSEP) of 508 µg.kg-1 for the test validation set and a ratio of performance to deviation of 4.7. It was concluded that NIR-HSI with partial least square regression is a rapid, effective, and non-destructive method to determine the fumonisin content in whole maize grains.
Assuntos
Fumonisinas , Imageamento Hiperespectral , Espectroscopia de Luz Próxima ao Infravermelho , Zea mays , Zea mays/química , Fumonisinas/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Imageamento Hiperespectral/métodos , Reprodutibilidade dos Testes , Quimiometria/métodosRESUMO
Understanding COVID-19 exposure differences among Healthcare Workers (HCWs) across various healthcare units is crucial for their protection and effective management of future outbreaks. However, comparative data on COVID-19 among HCWs in different healthcare units are scarce in Brazil. This study evaluated the relationship between SARS-CoV-2 infection and workplaces in HCWs from three distinct healthcare settings in Brazil. It also examined COVID-19 symptom dynamics reported by them. The cohort comprised 464 HCWs vaccinated with two doses of CoronaVac and a BNT162b2 booster from different institutions: Primary Health Care Units (PHCUs), Emergency Care Units (ECUs), and Hospitals. Participants answered a questionnaire and underwent blood collection at various time points after vaccinations. RT-PCR data and post-vaccination antibody responses were utilized as indicators of SARS-CoV-2 infection. We found that most infected HCWs worked in ECUs, where positive RT-PCR percentages were higher compared to PHCUs and Hospitals. ECUs also showed the highest seropositivity and antibody levels, especially after the first CoronaVac dose. The second dose of CoronaVac diminished the differences in the antibody levels among HCWs from ECUS, PHCUs, and Hospitals, indicating the benefit of the second dose to equalize the antibody levels between previously exposed and unexposed persons. Moreover, COVID-19 symptoms appeared to evolve over time.
Assuntos
COVID-19 , Saúde Pública , Humanos , Brasil/epidemiologia , Vacina BNT162 , SARS-CoV-2 , Pessoal de Saúde , Anticorpos AntiviraisRESUMO
OBJECTIVES: The objective of this study was to compare waveforms obtained with a new device for the non-invasive monitoring of intracranial pressure (ICP) in dogs with and without neurological disease. MATERIALS AND METHODS: This prospective study was conducted on both neurologically normal dogs and dogs with neurological diseases. First, non-invasive ICP waveforms were recorded in normal dogs using the Braincare® BcMM 2000 monitor while the dogs were under general anaesthesia induced for procedures unrelated to this study. The dogs were positioned in lateral recumbency, and the sensor was placed over the skin of the parietal region. Secondly, non-invasive ICP waveforms were monitored in dogs with brain and spinal disease until waveforms with characteristic peaks were acquired. All the recorded signals were amplified, filtered and digitalized, by the device, and then transferred to a computer for analysis. RESULTS: Normal pulse waveforms indicating normal brain complacency were observed in eight neurologically normal dogs. In six dogs with brain disease, abnormal pulse waveforms were observed suggesting increased ICP and decreased brain complacency. Four dogs with spinal disease undergoing myelography, had normal waveforms before contrast medium injection and abnormal pulse waveforms during contrast medium injection, indicating a potential increase in ICP. CLINICAL SIGNIFICANCE: Based on these preliminary observations, this method was capable of detecting abnormal pulse waveforms that suggested increased ICP.
Assuntos
Doenças do Cão , Hipertensão Intracraniana , Doenças da Coluna Vertebral , Animais , Cães , Hipertensão Intracraniana/veterinária , Pressão Intracraniana , Monitorização Fisiológica/veterinária , Estudos Prospectivos , Doenças da Coluna Vertebral/veterináriaRESUMO
Two experiments were carried out to test better stocking proportion according to animal size for tilapia (Oreochromis niloticus) and tadpole (Lithobates catesbeianus). The experiments were laid out in a completely randomized design with five treatments (in Experiment I) and four treatments (in Experiment II). In Experiment I, the treatments consisted of a tilapia monoculture; a 75% tilapia + 25% tadpole polyculture; a 50% tilapia + 50% tadpole; a 25% tilapia + 75% tadpole; and a tadpole monoculture. In Experiment II, the treatments were represented by a tilapia monoculture; a 12.5% tilapia + 87.5% tadpole polyculture; a 25% tilapia + 75% tadpole; and a tadpole monoculture. In the first trial, mortality rate differed significantly, with the polyculture treatments having almost 100% mortality of tadpoles. In the second experiment, after adjustments in the initial size of the species, there were significant differences between treatments, with the 12.5% tilapia + 87.5% tadpole polyculture and the tadpole monoculture providing the best results. Regardless of the chosen density, for a polyculture of Nile tilapia and bullfrog tadpoles, ideal conditions would be stocking tilapia fry weighing 50% of the weight initial tadpoles and the proportion of one tilapia for seven tadpoles.
Assuntos
Ciclídeos , Tilápia , Animais , Larva , Rana catesbeianaRESUMO
Given the scarcity of studies with elderly and the existence of studies investigating the effect of vitamin D supplementation in PEH (post exercise hypotension), this study evaluated the effect of a single megadose of vitamin D on resting blood pressure (RBP) and post-exercise hypotension (PEH) in the elderly. 11 hypertensive elderly women (70.3 ± 1.7 years) received a single megadose of 200.000 IU of cholecalciferol or a placebo, orally, through capsules. On day 7, the subjects performed 30 minutes of aerobic exercise with blood pressure measurement before exercise and every 10 minutes after exercise during 60 minutes, besides cardiac autonomic modulation. RBP did not significantly change. Exercise promoted significant systolic PEH only in one moment post exercise in treated group and in the placebo group promoted significant systolic PEH at four moments. Significant diastolic PEH did not occur in any of the groups. Sympathovagal activity increased at post exercise balance in supplemented subjects at 20 min, 40 min, 50 min and 60 min when compared to rest; this increase was not observed in the placebo. A megadose of vitamin D did not reduce RBP, promoted partial inhibition of systolic PEH and increased sympathovagal balance.
Assuntos
Sistema Nervoso Autônomo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Hipotensão Pós-Exercício/tratamento farmacológico , Deficiência de Vitamina D/tratamento farmacológico , Vitamina D/administração & dosagem , Idoso , Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea/fisiologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Projetos Piloto , Hipotensão Pós-Exercício/fisiopatologia , Deficiência de Vitamina D/fisiopatologiaRESUMO
Campylobacter jejuni é o principal causador de gastroenterite bacteriana aguda, e a carne de frango tem se mostrado uma importante fonte de transmissão. Este microrganismo é de difícil isolamento e os métodos convencionais muitas vezes não são eficientes, podendo levar a resultados errôneos. O objetivo deste trabalho foi desenvolver e testar a técnica de separação imunomagnética (IMS) na detecção de C. jejuni em produtos de frango. Micropartículas magnéticas ligadas a anticorpos policlonais anti-C. jejuni foram utilizadas para concentrar C. jejuni antes da semeadura em ágar. O protocolo foi comparado com o método convencional. C. jejuni foi recuperado do alimento experimentalmente contaminado por ambos os métodos, entretanto, quando foi usada a IMS, a presença de microrganismos contaminantes nos meios de cultura foi menor. C. jejuni foi isolado de 7% das amostras de alimento naturalmente contaminadas, usando IMS, e de 3% pelo método convencional. C. coli foi isolado de uma amostra pelo método convencional, mas não foi detectado pelo protocolo com IMS. A técnica de IMS pode ser usada para isolamento de C. jejuni de alimentos, oferecendo a vantagem de detectar em amostras o microrganismo cujo isolamento não é obtido por meio do método convencional.(AU)
Campylobacter jejuni is the main cause of acute bacterial gastroenteritis and chicken meat has shown to be an important source of infection. This microorganism is difficult to isolate and the conventional methods are often inefficient and may lead to erroneous results. This study aimed at developing and testing the technique of immunomagnetic separation (IMS) in the detection of C. jejuni in chicken products. Microparticles magnetically connected anti-C. jejuni polyclonal antibodies were used to concentrate C. jejuni before agar seeding. The protocol was compared with the conventional method. C. jejuni was recovered from experimentally contaminated food for both methods, however, when the IMS was used, the presence of contaminating microorganisms in the means of culture was smaller. C. jejuni was isolated from 7% of samples of food naturally contaminated, using IMS, and 3% by conventional method. C. coli was isolated from a sample by conventional method, but it was not detected by protocol with IMS. The IMS technique can be used for isolation of C. jejuni in food, offering the advantage of detecting the microorganism in samples from which the isolation is not obtained with the use of the conventional method.(AU)
Assuntos
Produtos Avícolas/microbiologia , Produtos Avícolas/toxicidade , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/isolamento & purificação , GalinhasRESUMO
Campylobacter jejuni é o principal causador de gastroenterite bacteriana aguda, e a carne de frango tem se mostrado uma importante fonte de transmissão. Este microrganismo é de difícil isolamento e os métodos convencionais muitas vezes não são eficientes, podendo levar a resultados errôneos. O objetivo deste trabalho foi desenvolver e testar a técnica de separação imunomagnética (IMS) na detecção de C. jejuni em produtos de frango. Micropartículas magnéticas ligadas a anticorpos policlonais anti-C. jejuni foram utilizadas para concentrar C. jejuni antes da semeadura em ágar. O protocolo foi comparado com o método convencional. C. jejuni foi recuperado do alimento experimentalmente contaminado por ambos os métodos, entretanto, quando foi usada a IMS, a presença de microrganismos contaminantes nos meios de cultura foi menor. C. jejuni foi isolado de 7% das amostras de alimento naturalmente contaminadas, usando IMS, e de 3% pelo método convencional. C. coli foi isolado de uma amostra pelo método convencional, mas não foi detectado pelo protocolo com IMS. A técnica de IMS pode ser usada para isolamento de C. jejuni de alimentos, oferecendo a vantagem de detectar em amostras o microrganismo cujo isolamento não é obtido por meio do método convencional.(AU)
Campylobacter jejuni is the main cause of acute bacterial gastroenteritis and chicken meat has shown to be an important source of infection. This microorganism is difficult to isolate and the conventional methods are often inefficient and may lead to erroneous results. This study aimed at developing and testing the technique of immunomagnetic separation (IMS) in the detection of C. jejuni in chicken products. Microparticles magnetically connected anti-C. jejuni polyclonal antibodies were used to concentrate C. jejuni before agar seeding. The protocol was compared with the conventional method. C. jejuni was recovered from experimentally contaminated food for both methods, however, when the IMS was used, the presence of contaminating microorganisms in the means of culture was smaller. C. jejuni was isolated from 7% of samples of food naturally contaminated, using IMS, and 3% by conventional method. C. coli was isolated from a sample by conventional method, but it was not detected by protocol with IMS. The IMS technique can be used for isolation of C. jejuni in food, offering the advantage of detecting the microorganism in samples from which the isolation is not obtained with the use of the conventional method.(AU)
Assuntos
Produtos Avícolas/microbiologia , Produtos Avícolas/toxicidade , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/isolamento & purificação , GalinhasRESUMO
The search for antiprion compounds has been encouraged by the fact that transmissible spongiform encephalopathies (TSEs) share molecular mechanisms with more prevalent neurodegenerative pathologies, such as Parkinson's and Alzheimer's diseases. Cellular prion protein (PrPC) conversion into protease-resistant forms (protease-resistant PrP [PrPRes] or the scrapie form of PrP [PrPSc]) is a critical step in the development of TSEs and is thus one of the main targets in the screening for antiprion compounds. In this work, three trimethoxychalcones (compounds J1, J8, and J20) and one oxadiazole (compound Y17), previously identified in vitro to be potential antiprion compounds, were evaluated through different approaches in order to gain inferences about their mechanisms of action. None of them changed PrPC mRNA levels in N2a cells, as shown by reverse transcription-quantitative real-time PCR. Among them, J8 and Y17 were effective in real-time quaking-induced conversion reactions using rodent recombinant PrP (rPrP) from residues 23 to 231 (rPrP23-231) as the substrate and PrPSc seeds from hamster and human brain. However, when rPrP from residues 90 to 231 (rPrP90-231), which lacks the N-terminal domain, was used as the substrate, only J8 remained effective, indicating that this region is important for Y17 activity, while J8 seems to interact with the PrPC globular domain. J8 also reduced the fibrillation of mouse rPrP23-231 seeded with in vitro-produced fibrils. Furthermore, most of the compounds decreased the amount of PrPC on the N2a cell surface by trapping this protein in the endoplasmic reticulum. On the basis of these results, we hypothesize that J8, a nontoxic compound previously shown to be a promising antiprion agent, may act by different mechanisms, since its efficacy is attributable not only to PrP conversion inhibition but also to a reduction of the PrPC content on the cell surface.
Assuntos
Chalconas/farmacologia , Drogas em Investigação/farmacologia , Neurônios/efeitos dos fármacos , Oxidiazóis/farmacologia , Proteínas Priônicas/antagonistas & inibidores , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Chalconas/síntese química , Clonagem Molecular , Drogas em Investigação/síntese química , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Cinética , Camundongos , Simulação de Acoplamento Molecular , Neurônios/metabolismo , Neurônios/patologia , Oxidiazóis/síntese química , Proteínas Priônicas/química , Proteínas Priônicas/genética , Proteínas Priônicas/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , TermodinâmicaRESUMO
O objetivo deste estudo foi utilizar a sonda uretral flexível como método alternativo para aferição da pressão intracraniana em coelhos com trauma cranioencefálico induzido pelo cateter de Fogarty 4 Fr (balão epidural) e comparar os dados obtidos com o método convencional de cateter de ventriculostomia. Foram utilizados 12 coelhos, machos, adultos, distribuídos aleatoriamente em dois grupos, denominados de G1: mensuração da PIC com cateter de ventriculostomia (n=6) e G2: mensuração com sonda uretral (n=6). Foram realizadas duas craniotomias na região parietal direita e esquerda para a implantação do cateter de ventriculostomia ou sonda uretral flexível e o balão epidural, respectivamente. A PAM, a PPC, a FC, a FR e a TR foram mensurados antes e após a craniotomia. A PIC foi avaliada após a craniotomia e a cada 10 minutos depois do preenchimento do balonete com 0,3mL de NaCl 0,9%, durante 40 minutos, e com 0,6mL, pelo mesmo período de tempo, totalizando 80 minutos. A PIC aumentou em ambos os grupos, sendo menores os valores registrados com a sonda uretral flexível. Foi possível reproduzir o aumento da PIC com o modelo experimental de TCE utilizando o cateter de Fogarty 4 Fr na região epidural e, embora haja a necessidade de outros estudos, a sonda uretral flexível demonstra ser um método alternativo de mensuração da PIC em coelhos com trauma cranioencefálico.(AU)
The aim of this study was to evaluate the use of flexible urethral catheter as an alternative method for measuring intracranial pressure in rabbits with head trauma induced by 4 F Fogarty catheter (epidural balloon) and compare the data obtained with the conventional method of ventriculostomy catheter. In this study, New Zealand rabbits were randomly distributed into two groups, G1: measuring the ICP with ventriculostomy catheter (n=6) and G2: measuring the ICP with urethral catheter (n=6). Two craniotomies were performed in the right and left parietal region for the implantation of a ventriculostomy catheter and/or flexible urethral catheter and epidural 4 Fr Fogarty arterial embolectomy catheter, respectively. MAP, CPP, HR, RF and RT values were measured before and after of the craniotomy. The ICP value was measured after craniotomy, every five minutes during 40 minutes after the balloon was inflated with 0.3 ml with NaCl and further 40 minutes after the balloon was inflated with 0.6 ml. The ICP value increased in both groups; however, the ICP values were lower in the flexible urethral catheter. The flexible urethral catheter can be used as an alternative method to measure ICP values in rabbits with head injury.(AU)
Assuntos
Animais , Coelhos , Pressão Intracraniana , Equipamentos de Medição de Riscos , Cateterismo Urinário , Cateterismo Urinário/veterinária , Traumatismos Craniocerebrais/diagnóstico , Ventriculostomia/veterináriaRESUMO
O objetivo deste estudo foi utilizar a sonda uretral flexível como método alternativo para aferição da pressão intracraniana em coelhos com trauma cranioencefálico induzido pelo cateter de Fogarty 4 Fr (balão epidural) e comparar os dados obtidos com o método convencional de cateter de ventriculostomia. Foram utilizados 12 coelhos, machos, adultos, distribuídos aleatoriamente em dois grupos, denominados de G1: mensuração da PIC com cateter de ventriculostomia (n=6) e G2: mensuração com sonda uretral (n=6). Foram realizadas duas craniotomias na região parietal direita e esquerda para a implantação do cateter de ventriculostomia ou sonda uretral flexível e o balão epidural, respectivamente. A PAM, a PPC, a FC, a FR e a TR foram mensurados antes e após a craniotomia. A PIC foi avaliada após a craniotomia e a cada 10 minutos depois do preenchimento do balonete com 0,3mL de NaCl 0,9%, durante 40 minutos, e com 0,6mL, pelo mesmo período de tempo, totalizando 80 minutos. A PIC aumentou em ambos os grupos, sendo menores os valores registrados com a sonda uretral flexível. Foi possível reproduzir o aumento da PIC com o modelo experimental de TCE utilizando o cateter de Fogarty 4 Fr na região epidural e, embora haja a necessidade de outros estudos, a sonda uretral flexível demonstra ser um método alternativo de mensuração da PIC em coelhos com trauma cranioencefálico.(AU)
The aim of this study was to evaluate the use of flexible urethral catheter as an alternative method for measuring intracranial pressure in rabbits with head trauma induced by 4 F Fogarty catheter (epidural balloon) and compare the data obtained with the conventional method of ventriculostomy catheter. In this study, New Zealand rabbits were randomly distributed into two groups, G1: measuring the ICP with ventriculostomy catheter (n=6) and G2: measuring the ICP with urethral catheter (n=6). Two craniotomies were performed in the right and left parietal region for the implantation of a ventriculostomy catheter and/or flexible urethral catheter and epidural 4 Fr Fogarty arterial embolectomy catheter, respectively. MAP, CPP, HR, RF and RT values were measured before and after of the craniotomy. The ICP value was measured after craniotomy, every five minutes during 40 minutes after the balloon was inflated with 0.3 ml with NaCl and further 40 minutes after the balloon was inflated with 0.6 ml. The ICP value increased in both groups; however, the ICP values were lower in the flexible urethral catheter. The flexible urethral catheter can be used as an alternative method to measure ICP values in rabbits with head injury.(AU)