Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 258
Filtrar
3.
Anal Methods ; 16(18): 2938-2947, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38668806

RESUMO

The nature and proportions of hydrocarbons in the cuticle of insects are characteristic of the species and age. Chemical analysis of cuticular hydrocarbons allows species discrimination, which is of great interest in the forensic field, where insects play a crucial role in estimating the minimum post-mortem interval. The objective of this work was the differentiation of Diptera order insects through their saturated cuticular hydrocarbon compositions (SCHCs). For this, specimens fixed in 70 : 30 ethanol : water, as recommended by the European Association for Forensic Entomology, were submitted to solid-liquid extraction followed by dispersive liquid-liquid microextraction, providing preconcentration factors up to 76 for the SCHCs. The final organic extract was analysed by gas chromatography coupled with flame ionization detection (GC-FID), and GC coupled with mass spectrometry was applied to confirm the identity of the SCHCs. The analysed samples contained linear alkanes with the number of carbon atoms in the C9-C15 and C18-C36 ranges with concentrations between 0.1 and 125 ng g-1. Chrysomya albiceps (in its larval stage) showed the highest number of analytes detected, with 21 compounds, while Lucilia sericata and Calliphora vicina the lowest, with only 3 alkanes. Non-supervised principal component analysis and supervised orthogonal partial least squares discriminant analysis were performed and an optimal model to differentiate specimens according to their species was obtained. In addition, statistically significant differences were observed in the concentrations of certain SCHCs within the same species depending on the stage of development or the growth pattern of the insect.


Assuntos
Dípteros , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos , Animais , Hidrocarbonetos/análise , Dípteros/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Líquida/métodos , Entomologia Forense/métodos , Análise de Componente Principal , Análise Discriminante
6.
Domest Anim Endocrinol ; 84-85: 106806, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37392553

RESUMO

Recent research has suggested that different cattle breed types may respond differently to anabolic implant protocols of varying intensity. Therefore, the purpose of this research was to compare anabolic implant protocols in feedlot steers of 2 different breed types. Sixty steers were stratified by weight and breed in a 2 × 3 factorial design examining 2 different breeds: Angus (AN; n=38) or Santa Gertrudis influenced (SG; n=22), and 3 implant strategies: no implant (CON; n=20), a moderate intensity implant protocol (d0 implant: Revalor-G, d56 implant: Revalor-IS, d112 implant: Revalor-S; MI; n=20), or a high intensity implant protocol (d0 implant: Revalor-IS, d56 implant: Revalor-S, d112 implant: Revalor-200; HI; n=20). Steers were randomly placed into pens equipped with GrowSafe bunks to collect dry matter intake and feeding behavior. All animals were fed the same diet. Weight, chute score, exit velocity, serum, rectal temperature, hip height and 12th rib fat thickness were collected approximately every 28 d over a 196 d period. Serum urea nitrogen (SUN) was evaluated as well. Total average daily gain was increased (P < 0.0001) in both the HI and MI steers compared to the CON steers by 29.4% and 26%, respectively. A treatment × breed interaction was observed (P < 0.0001) for hip height, with AN-CON steers being shorter (P < 0.0007) than AN-HI, SG-CON, SG-MI, and SG-HI steers. A breed × treatment interaction was observed (P < 0.004) for chute score and rectal temperature, with SG-HI and SG-MI steers having increased chute scores (P < 0.001) when compared to AN-HI, AN-MI, AN-CON, and SG-CON throughout the course of the trial. Additionally, SG-HI and SG-MI steers had an increased rectal temperature (P < 0.004) compared to AN-HI, AN-MI, AN-CON, and SG-CON steers. A breed effect was observed (P = 0.002) for SUN with AN steers having increased (P = 0.002) SUN concentration compared to SG sired steers, in addition to a treatment effect (P < 0.0001), with CON steers having a higher (P < 0.0001) SUN concentration than MI and HI steers, regardless of breed. The MI implant protocol increased net return per head, on average, by $97.28, regardless of breed, while the HI implant protocol increased net return by only $80.84. Taken together, despite the cattle breed types responding differently to the different anabolic implant protocols at times, a moderate intensity anabolic implant protocol was optimal in this experiment for steers raised in a temperate climate.


Assuntos
Dieta , Temperamento , Animais , Bovinos/genética , Ração Animal/análise , Nitrogênio da Ureia Sanguínea , Composição Corporal , Dieta/veterinária , Comportamento Alimentar
7.
Postgrad Med J ; 99(1173): 669-678, 2023 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-37389581

RESUMO

Paraneoplastic neurological syndromes (PNSs) comprise a subset of immune-mediated nervous system diseases triggered by an underlying malignancy. Each syndrome usually shows a distinct clinical presentation and outcome according to the associated neural antibodies. PNSs generally have a subacute onset with rapid progression and severe neurological disability. However, some patients may have hyperacute onset or even show chronic progression mimicking neurodegenerative diseases. Updated diagnostic criteria for PNS have been recently established in order to increase diagnostic specificity and to encourage standardisation of research initiatives related to PNS. Treatment for PNS includes oncological therapy and immunomodulation to halt neurological deterioration although current treatment options are seldom effective in reversing disability. Nevertheless, growing knowledge and better understanding of PNS pathogenesis promise better recognition, earlier diagnosis and novel treatment strategies. Considering that PNSs provide a model of effective anticancer immunity, the impact of these studies will extend far beyond the field of neurology.


Assuntos
Encefalite , Neurologia , Humanos , Encefalite/diagnóstico , Encefalite/terapia
9.
PLoS One ; 18(4): e0284218, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37053294

RESUMO

To accurately assess pain and support broadly-based analgesic protocols to mitigate swine pain, it is imperative to develop and validate a species-specific pain scale. The objective of this study was to investigate the clinical validity and reliability of an acute pain scale (UPAPS) adapted for newborn piglets undergoing castration. Thirty-nine male piglets (five days of age, 1.62 ± 0.23 kg BW) served as their own control, were enrolled in the study and underwent castration in conjunction with an injectable analgesic administered one-hour post-castration (flunixin meglumine 2.2 mg/kg IM). An additional 10, non-painful female piglets were included to account for the effect of natural behavioral variation by day on pain scale results. Behavior of each piglet was video recorded continuously at four recording periods (24 h pre-castration, 15 min post-castration, 3 and 24 h post-castration). Pre- and post-operative pain was assessed by using a 4-point scale (score 0-3) including the following six behavioral items: posture, interaction and interest in surroundings, activity, attention to the affected area, nursing, and miscellaneous behavior. Behavior was assessed by two trained blinded observers and statistical analysis was performed using R software. Inter-observer agreement was very good (ICC = 0.81). The scale was unidimensional based on the principal component analysis, all items except for nursing were representative (rs ≥ 0.74) and had excellent internal consistency (Cronbach's alpha ≥ 0.85). The sum of scores were higher in castrated piglets post-procedure compared to pre-procedure, and higher than in non-painful female piglets confirming responsiveness and construct validity, respectively. Scale sensitivity was good when piglets were awake (92.9%) and specificity was moderate (78.6%). The scale had excellent discriminatory ability (area under the curve > 0.92) and the optimal cut-off sum for analgesia was 4 out of 15. The UPAPS scale is a valid and reliable clinical tool to assess acute pain in castrated pre-weaned piglets.


Assuntos
Dor Aguda , Analgesia , Animais , Masculino , Feminino , Suínos , Dor Aguda/diagnóstico , Reprodutibilidade dos Testes , Orquiectomia/veterinária , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/tratamento farmacológico
10.
Postgrad Med J ; 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37036000

RESUMO

Paraneoplastic neurological syndromes (PNSs) comprise a subset of immune-mediated nervous system diseases triggered by an underlying malignancy. Each syndrome usually shows a distinct clinical presentation and outcome according to the associated neural antibodies. PNSs generally have a subacute onset with rapid progression and severe neurological disability. However, some patients may have hyperacute onset or even show chronic progression mimicking neurodegenerative diseases. Updated diagnostic criteria for PNS have been recently established in order to increase diagnostic specificity and to encourage standardisation of research initiatives related to PNS. Treatment for PNS includes oncological therapy and immunomodulation to halt neurological deterioration although current treatment options are seldom effective in reversing disability. Nevertheless, growing knowledge and better understanding of PNS pathogenesis promise better recognition, earlier diagnosis and novel treatment strategies. Considering that PNSs provide a model of effective anticancer immunity, the impact of these studies will extend far beyond the field of neurology.

13.
Sci Total Environ ; 859(Pt 2): 160462, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36435246

RESUMO

The use of reclaimed water for crop irrigation has been proposed as a suitable alternative for farmers in the coastal areas of Mediterranean countries, which suffer from greater water scarcity. In this work we study the impact on the water-soil-plant continuum of using reclaimed water for commercial crops irrigated over a long period, as well as the human risks associated with consuming the vegetables produced. Forty-four CECs were identified in the reclaimed water used for crop irrigation. Of these, twenty-four CECs were identified in the irrigated soil samples analysed. Tramadol, ofloxacin, tonalide, gemfibrozil, atenolol, caffeine, and cetirizine were the pharmaceuticals detected at the highest levels in the water samples (between 11 and 44 µg/L). The CECs with the highest average soil concentrations were tramadol (14.6 µg/kg), followed by cetirizine (13.2 µg/kg) and clarithromycin (12.7 µg/kg). In the irrigated vegetable samples analysed over the study period, carbamazepine, lidocaine, and caffeine were only detected at levels from 0.1 to 1.7 µg/kg. The CEC accumulation rate detected in the edible parts of the vegetables permanently irrigated with reclaimed water was very low (~1 %), whereas it was 33 % in the soils. The results revealed that consuming fruits harvested from plants irrigated for a long period with reclaimed water does not represent a risk to human health, opening the door to a circular economy of water. Nevertheless, for crop irrigation, future studies need to be conducted over longer periods and in other matrices to provide more scientific data on the safety of using reclaimed water.


Assuntos
Irrigação Agrícola , Poluentes do Solo , Humanos , Água/análise , Águas Residuárias , Produtos Agrícolas , Solo , Verduras , Poluentes do Solo/análise
14.
Artigo em Inglês | MEDLINE | ID: mdl-36403725

RESUMO

OBJECTIVES: Main objective: To compare the effectiveness for checking surgical margins between SPECT-portable and mammography of the piece (RxM). SECONDARY OBJECTIVE: To standardize a pre-operative protocol using SPECT-portable and to evaluate the time required in the use of this technique. MATERIAL AND METHODS: Prospective longitudinal study with 36 patients (39 lesions) diagnosed with breast cancer (CM) with criteria for SNOLL/ROLL. A pre-surgical study of the tumor lesion was performed, after the eco-guided administration of 99mTc-nanocolloids of albumin/99mTc-macroaggregates of albumin, in the tumor lesion. Hybrid images (optical + SPECT) and 3D navigation images with gamma probe are obtained using freehandSPECT. In the operating room, 4-5 images are obtained with freehandSPECT, (I) on skin for tumor location, (II) after exposure of surgical bed for resection guide, (III) of the surgical bed after exeresis, (IV and V) the anterior-posterior and lateral surface of the surgical specimen. The three criteria to decide to extend the margins are: (a) residual activity (cps) at the edges of the surgical bed resection; (b) visual analysis of the uptake in the specimen; (c) a minimum distance of 10 mm from the edges of the specimen to the center of greatest uptake, plus the radius of the lesion. We study the concordance of: the depth measurement between ultrasound and freehandSPECT; the surgical margins between freehandSPECT vs. mammography of the specimen (RxM), considering anatomical pathology (AP) as the gold standard technique as reference; surgical time used with freehandSPECT and RxM. RESULTS: Intraoperative localization was performed in all cases. False negative (FN: no detection margin affected) with freehandSPECT: 9 margins; with RxM: 8. True positive (TP: detection margin affected) with freehandSPECT: 5 margins, with RxM: 6. True negative (TN: consider free margin when healthy) with freehandSPECT: 213 margins; with RxM: 196. Negative predictive value (NPV: probability of negative margin on unaffected part) with freehandSPECT: 95.9%, with RxM: 96.07%. Specificity with freehandSPECT: 96.8%, with RxM: 97%. The concordance of surgical bed margins between freehandSPECT and RxM: 94.5%. Between freehandSPECT and AP: 93.1%. Between RxM and PA: 93.5%, being all statistically significant (p-value <0.000), so we can affirm that both techniques are related or dependent on the reference technique, the PA. Degree of correlation between SPECT-portable and low PA (Kappa index: 0.34, 95% CI [0.22-0.47], and between RxM and moderate PA (Kappa index: 0.42, 95% CI [0.29-0.56], p-value <0.001. Comparison of the successes and failures of both techniques (SPECT-portable and RxM) and PA: Distribution χ2: 0.023 with degree of freedom 1, with value <0.05, so we can affirm that both techniques are similar, since there are no significant statistical differences. Median total OR time: 60.25 min (30-145). Mean freehandSPECT OR time: 5 scans = 10 min. CONCLUSIONS: There are no statistically significant differences in the probability to rule out affective margins that require a second surgery between both techniques (SPECT-portable and RxM) so, the technique performed with SPECT-Portable is a useful and effective procedure, which requires specific training with an optimized and multidisciplinary protocol. The time spent with SPECT-portable is feasible for daily practice.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Margens de Excisão , Estudos Prospectivos , Estudos Longitudinais , Tomografia Computadorizada de Emissão de Fóton Único , Albuminas
15.
Bioresour Technol ; 368: 128322, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36396037

RESUMO

Biodegradability of biomass constituents is the reason for the gap between theoretical biogas/methane yield and the maximum yield obtainable in bioconversion. The prediction of biogas/methane yields by applying thermal analysis is a relatively new development in this field. The aim of this study was to develop a bioconversion model based on thermogravimetry. Eleven substrates with a specific biogas yield within the range 104 to 572 mLN per gram of volatile solids were subjected to thermogravimetry and a multi linear regression model was developed to predict biogas and methane yields. The optimum parameters describe biogas and methane yields with a root mean square error of 58.8 and 34.3 mLN per gram of volatile solids respectively. The coefficient of determination for these two datasets was 0.81 and 0.84. A prediction technique based on thermogravimetric analysis appears to be a good alternative to other prediction models.


Assuntos
Biocombustíveis , Metano , Termogravimetria , Biomassa , Modelos Lineares
17.
Nature ; 612(7939): 228-231, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36477127

RESUMO

Gamma-ray bursts (GRBs) are flashes of high-energy radiation arising from energetic cosmic explosions. Bursts of long (greater than two seconds) duration are produced by the core-collapse of massive stars1, and those of short (less than two seconds) duration by the merger of compact objects, such as two neutron stars2. A third class of events with hybrid high-energy properties was identified3, but never conclusively linked to a stellar progenitor. The lack of bright supernovae rules out typical core-collapse explosions4-6, but their distance scales prevent sensitive searches for direct signatures of a progenitor system. Only tentative evidence for a kilonova has been presented7,8. Here we report observations of the exceptionally bright GRB 211211A, which classify it as a hybrid event and constrain its distance scale to only 346 megaparsecs. Our measurements indicate that its lower-energy (from ultraviolet to near-infrared) counterpart is powered by a luminous (approximately 1042 erg per second) kilonova possibly formed in the ejecta of a compact object merger.


Assuntos
Astros Celestes
18.
Nature ; 600(7890): 621-624, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34937892

RESUMO

Magnetars are strongly magnetized, isolated neutron stars1-3 with magnetic fields up to around 1015 gauss, luminosities of approximately 1031-1036 ergs per second and rotation periods of about 0.3-12.0 s. Very energetic giant flares from galactic magnetars (peak luminosities of 1044-1047 ergs per second, lasting approximately 0.1 s) have been detected in hard X-rays and soft γ-rays4, and only one has been detected from outside our galaxy5. During such giant flares, quasi-periodic oscillations (QPOs) with low (less than 150 hertz) and high (greater than 500 hertz) frequencies have been observed6-9, but their statistical significance has been questioned10. High-frequency QPOs have been seen only during the tail phase of the flare9. Here we report the observation of two broad QPOs at approximately 2,132 hertz and 4,250 hertz in the main peak of a giant γ-ray flare11 in the direction of the NGC 253 galaxy12-17, disappearing after 3.5 milliseconds. The flare was detected on 15 April 2020 by the Atmosphere-Space Interactions Monitor instrument18,19 aboard the International Space Station, which was the only instrument that recorded the main burst phase (0.8-3.2 milliseconds) in the full energy range (50 × 103 to 40 × 106 electronvolts) without suffering from saturation effects such as deadtime and pile-up. Along with sudden spectral variations, these extremely high-frequency oscillations in the burst peak are a crucial component that will aid our understanding of magnetar giant flares.


Assuntos
Astros Celestes , Atmosfera
19.
Sci Rep ; 11(1): 21055, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702838

RESUMO

Aspergillus fumigatus is a fungal pathogen whose effects can be debilitating and potentially fatal in immunocompromised patients. Current drug treatment options for this infectious disease are limited to just a few choices (e.g. voriconazole and amphotericin B) and these themselves have limitations due to potentially adverse side effects. Furthermore, the likelihood of the development of resistance to these current drugs is ever present. Thus, new treatment options are needed for this infection. A new potential antifungal drug target is acetohydroxyacid synthase (AHAS; EC 2.2.1.6), the first enzyme in the branched chain amino acid biosynthesis pathway, and a target for many commercial herbicides. In this study, we have expressed, purified and characterised the catalytic subunit of AHAS from A. fumigatus and determined the inhibition constants for several known herbicides. The most potent of these, penoxsulam and metosulam, have Ki values of 1.8 ± 0.9 nM and 1.4 ± 0.2 nM, respectively. Molecular modelling shows that these compounds are likely to bind into the herbicide binding pocket in a mode similar to Candida albicans AHAS. We have also shown that these two compounds inhibit A. fumigatus growth at a concentration of 25 µg/mL. Thus, AHAS inhibitors are promising leads for the development of new anti-aspergillosis therapeutics.


Assuntos
Acetolactato Sintase , Antifúngicos/química , Aspergillus fumigatus/enzimologia , Proteínas Fúngicas , Herbicidas/química , Pirimidinas/química , Sulfonamidas/química , Triazóis/química , Uridina/análogos & derivados , Acetolactato Sintase/antagonistas & inibidores , Acetolactato Sintase/química , Candida albicans/enzimologia , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/química , Uridina/química
20.
Sci Total Environ ; 782: 146759, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33838369

RESUMO

In this study, we aimed to develop and validate a quick, easy, and robust extraction method for the simultaneous determination of 30 organic contaminants of emerging concern (CECs) including some transformation products in soil samples. Three different extraction methods based on an ultrasonic cylindrical probe (UAE), a pressurized liquid extraction (PLE), and a QuEChERS method were compared. Ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry (LC-MS/MS) was used for identification and quantification of the target analytes. A modified QuEChERS method showed the best results in terms of extractability and accuracy. The extraction procedure developed provided adequate extraction performances (70% of the target analytes were recovered within a 70-99% range), with good repeatability and reproducibility (variations below 20%) and great sensitivity (LOQ < 0.1 ng/g in most cases). No matrix effects were observed for 70% of the compounds. Finally, the analytical methodology was applied in a pilot study where agricultural soil was irrigated with reclaimed water spiked with the contaminants under study. Of the 25 CECs added in irrigation water, a total of 13 pesticides and 5 pharmaceutical products were detected at concentration ranges from 0.1 to 1.2 ng/g (d.w) and from 0.1 to 2.0 ng/g (d.w), respectively.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA