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1.
Comput Biol Med ; 171: 108216, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38442555

ABSTRACT

Despite being one of the most prevalent forms of cancer, prostate cancer (PCa) shows a significantly high survival rate, provided there is timely detection and treatment. Computational methods can help make this detection process considerably faster and more robust. However, some modern machine-learning approaches require accurate segmentation of the prostate gland and the index lesion. Since performing manual segmentations is a very time-consuming task, and highly prone to inter-observer variability, there is a need to develop robust semi-automatic segmentation models. In this work, we leverage the large and highly diverse ProstateNet dataset, which includes 638 whole gland and 461 lesion segmentation masks, from 3 different scanner manufacturers provided by 14 institutions, in addition to other 3 independent public datasets, to train accurate and robust segmentation models for the whole prostate gland, zones and lesions. We show that models trained on large amounts of diverse data are better at generalizing to data from other institutions and obtained with other manufacturers, outperforming models trained on single-institution single-manufacturer datasets in all segmentation tasks. Furthermore, we show that lesion segmentation models trained on ProstateNet can be reliably used as lesion detection models.


Subject(s)
Prostate , Prostatic Neoplasms , Male , Humans , Prostate/diagnostic imaging , Imaging, Three-Dimensional/methods , Retrospective Studies , Algorithms , Prostatic Neoplasms/diagnostic imaging , Magnetic Resonance Imaging/methods
3.
Food Microbiol ; 119: 104425, 2024 May.
Article in English | MEDLINE | ID: mdl-38225036

ABSTRACT

This study aimed to evaluate and identify the microbial community attached to the surfaces of fermenter tanks used in table olive Negrinha de Freixo cultivar processing through molecular analysis and verify if the cleaning/disinfection was done correctly. Four fermentation tanks previously used in table olive processing were sampled at three different inside areas: upper, middle, and lower. Before sampling, four cleaning/disinfection methods were applied to the tanks, including (i) pressurised water; (ii) a disinfectant product used to clean bowls (Vasiloxe); (iii) 10% sodium hydroxide solution (caustic soda liquid); and (iv) a disinfectant product used by the wine industry (Hosbit). For each sample collected, mesophilic aerobic bacteria, yeast and moulds (YMC), lactic acid bacteria (LAB), as well as total coliforms (TC) and Pseudomonas aeruginosa were evaluated. The results showed significant differences between the different cleaning/disinfection methods applied. The fermenter sanitised with only pressurised water showed a greater abundance of microorganisms than the others. Mesophilic aerobic bacteria were the predominant population, with counts ranging between 2.63 and 5.56 log10 CFU/100 cm2, followed by the moulds (3.11-5.03 log10 CFU/100 cm2) and yeasts (2.42-5.12 log10 CFU/100 cm2). High diversity of microbial communities was observed between the different fermenter tanks. The most abundant species belonged to Aureobasidium, Bacillaceae, Cladosporium, and Rhodotorula genera. LAB, TC, and P. aeruginosa were not detected. This study hopes to improve hygienic conditions and increase the quality assurance and safety of the final product.


Subject(s)
Disinfectants , Lactobacillales , Olea , Fermentation , Olea/microbiology , Disinfection , Gram-Negative Bacteria , Yeasts/genetics , Disinfectants/pharmacology , Water , Food Microbiology
4.
Chem Biodivers ; 21(2): e202301629, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38109266

ABSTRACT

Three Portuguese olive oils with PDO ('Azeite do Alentejo Interior', 'Azeites da Beira Interior' and 'Azeite de Trás-os-Montes') were studied considering their physicochemical quality, antioxidant capacity, oxidative stability, total phenols content, gustatory sensory sensations and Fourier transform infrared (FTIR) spectra. All oils fulfilled the legal thresholds of EVOOs and the PDO's specifications. Olive oils from 'Azeite da Beira Interior' and 'Azeite de Trás-os-Montes' showed greater total phenols contents and antioxidant capacities, while 'Azeites da Beira Interior' presented higher oxidative stabilities. Linear discriminant models were developed using FTIR spectra (transmittance and the 1st and 2nd derivatives), allowing the correct identification of the oils' PDO (100 % sensitivity and specificity, repeated K-fold-CV). This study also revealed that multiple linear regression models, based on FTIR transmittance data, could predict the sweet, bitter, and pungent intensities of the PDO oils (R2 ≥0.979±0.016; RMSE≤0.26±0.05, repeated K-fold-CV). This demonstrates the potential of using FTIR as a non-destructive technique for authenticating oils with PDO.


Subject(s)
Antioxidants , Phenols , Olive Oil/chemistry , Spectroscopy, Fourier Transform Infrared , Fourier Analysis , Portugal , Phenols/analysis , Plant Oils/chemistry
5.
Acta Med Port ; 36(12): 811-818, 2023 Dec 04.
Article in English | MEDLINE | ID: mdl-38048689

ABSTRACT

INTRODUCTION: Mental health warrants exist in most countries and are issued when patients have severe mental illness, refuse treatment, and present a serious risk to themselves or others. We describe the epidemiology of mental health warrant requests received, and warrants issued by a Public Health Unit in a Portuguese region, as well as subsequent hospital admissions before and during the COVID-19 pandemic. METHODS: We used routine administrative data of mental health warrant request entries from a Public Health Unit serving a population of 219 739 individuals and compared the average of monthly requests, issued warrants, and hospital admissions during two separate periods (January 2013 to January 2021 and February 2021 to October 2022) as well as the proportion of warrants issued, hospital admissions among requests, and other patient characteristics. We identified factors associated with hospital admissions among the requests using logistic regression. RESULTS: Monthly average warrant requests, issued warrants and hospital admissions increased after February 2021 (x̄ 2.87 vs 7.09 p < 0.001; x̄ 2.67 vs 6.42 p < 0.001; x̄ 1.55 vs 3.58 p < 0.001). We found no differences by period in the proportion of requests with issued warrants (92.8% vs 90.6% p = 0.42) nor the proportion of requests with subsequent hospital admissions (54.0% vs 49.0% p = 0.33). In the second period, there were differences in the proportion of patients with a previously diagnosed mental health disorder (95.3% vs 90.4% p = 0.049). There were significant differences in the distribution of the origin of requests. Being unemployed (OR:2.5 CI:1.2 - 5.2), not having completed high school (OR:2.01 CI:1.12 - 3.77) and having university education (OR:3.67 CI:1.27 - 10.57) degree were associated with hospital admission. CONCLUSION: Severe mental illness with criteria for mental health warrants may require more resources and different approaches due to a possible increase during and after the COVID-19 pandemic. Community based mental healthcare, incentivized follow-up by primary care and ambulatory treatment may be considered. Further research should evaluate both the national and international trends and associated factors.


Subject(s)
COVID-19 , Humans , COVID-19/epidemiology , Portugal/epidemiology , Mental Health , Pandemics , Hospitals
6.
J Imaging ; 9(10)2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37888300

ABSTRACT

Surface defect detection with machine learning has become an important tool in industries and a large field of study for researchers or workers in recent years. It is necessary to have a simplified source of information that helps us to better focus on one type of surface. In this systematic review, we present a classification for surface defect detection based on convolutional neural networks (CNNs) focused on surface types. Findings: Out of 253 records identified, 59 primary studies were eligible. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we analyzed the structures of each study and the concepts related to defects and their types on surfaces. The presented review is mainly focused on finding a classification for the types of surfaces most used in industry (metal, building, ceramic, wood, and special). We delve into the specifics of each surface category, offering illustrative examples of their applications within both industrial and laboratory settings. Furthermore, we propose a new taxonomy of machine learning based on the obtained results and collected information. We summarized the studies and extracted the main characteristics such as type of surface, problem types, timeline, type of network, techniques, and datasets. Among the most relevant results of our analysis, we found that the metallic surface is the most used, as it is the one found in 62.71% of the studies, and the most prevalent problem type is classification, accounting for 49.15% of the total. Furthermore, we observe that transfer learning was employed in 83.05% of the studies, while data augmentation was utilized in 59.32%. Our findings also provide insights into the cameras most frequently employed, along with the strategies adopted to address illumination challenges present in certain articles and the approach to creating datasets for real-world applications. The main results presented in this review allow for a quick and efficient search of information for researchers and professionals interested in improving the results of their defect detection projects. Finally, we analyzed the trends that could open new fields of study for future research in the area of surface defect detection.

7.
J Imaging ; 9(10)2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37888301

ABSTRACT

This paper presents a systematic review of articles on computer-vision-based flying obstacle detection with a focus on midair collision avoidance. Publications from the beginning until 2022 were searched in Scopus, IEEE, ACM, MDPI, and Web of Science databases. From the initial 647 publications obtained, 85 were finally selected and examined. The results show an increasing interest in this topic, especially in relation to object detection and tracking. Our study hypothesizes that the widespread access to commercial drones, the improvements in single-board computers, and their compatibility with computer vision libraries have contributed to the increase in the number of publications. The review also shows that the proposed algorithms are mainly tested using simulation software and flight simulators, and only 26 papers report testing with physical flying vehicles. This systematic review highlights other gaps to be addressed in future work. Several identified challenges are related to increasing the success rate of threat detection and testing solutions in complex scenarios.

8.
Children (Basel) ; 10(9)2023 Aug 27.
Article in English | MEDLINE | ID: mdl-37761421

ABSTRACT

BACKGROUND: After two years of psychological, physical, social, economic, environmental, and societal challenges, this paper examines the psychological health and well-being of Portuguese students based on their socioemotional skills (SSES), positive youth development (PYD), depression, anxiety, and stress (DASS), as well as the relationship between these variables and their influence on perceived quality of life and life satisfaction. METHODS: This study examined 3235 students from lower to upper secondary, half of whom were female (M = 14.46 ± 1.883 years old). Using SPSS software, descriptive statistics were determined for all variables; mean differences between age and gender were found using ANOVA and the post hoc Scheffe test. Linear regressions with the Enter method were used to study how to predict perceived quality of life and satisfaction with life. RESULTS: Males had scores indicating more SSES|optimism, emotional control, resilience, confidence, sociability, creativity, energy, a sense of belonging to school, and PYD. Girls had better skills for cooperating and relating to teachers but more test anxiety and DASS. Younger adolescents had better psychological health, greater skills, and a better perception of quality of life and life satisfaction when compared to older adolescents. Age, gender, SSES, PYD, and the DASS variables can explain 69% of the variance in life satisfaction, while these variables can explain 60.5% of the variance in perceived quality of life. CONCLUSIONS: These results point to the relevance of SSES for psychological health and well-being, suggesting that interventions should focus on promoting these variables, paying special attention to female gender and age-related challenges.

9.
Heliyon ; 9(8): e19122, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37636464

ABSTRACT

Since 2001, in Portugal, constant reforms in hospital management have accompanied the transformations in the management models applied to public administration, intending to ensure a higher quality of services and, simultaneously, a more significant economic efficiency. This study aims to analyse, for the period between 2012 and 2021, the economic and financial results (value-for-money) of the PPP model, compared with the public management hospitals (PMH). It used a mixed research approach based on multiple case studies and archival research. As the main results, it was found that: i) the PPP model, applied to the health sector, appears to be advantageous, not only regarding the economic and financial results but also concerning the quality of service provision; and ii) despite the value-for-money generated by the PPP model, the lower operating costs and the superior performance in comparison with PMH, the government has permanently opted to revert from a PPP model to a PMH model. This study concluded that the hospital management model is instead seen as an instrumentalised political instrument than a management tool that could generate savings for the taxpayers. Several practical implications are presented.

10.
Healthcare (Basel) ; 11(12)2023 Jun 12.
Article in English | MEDLINE | ID: mdl-37372841

ABSTRACT

In this paper, a conceptual framework for investigating the PPP model as it relates to hospitals is proposed. When the PPP model is applied to healthcare (hospitals), it is possible to discover the path to success by developing a critical assessment and deriving a clear model. It is concluded that most PPP model implementations in hospitals around the world have produced favorable outcomes, both in terms of the performance of healthcare units and in terms of cost-effectiveness. Additionally, a path-to-success model that applies to hospitals is offered, taking into account six PPP model dimensions: (i) Environment; (ii) Potentiate Benefits; (iii) Constant Measure; (iv) Evaluation; (v) Management; and (vi) Enhance Strengths. The PPP model only applies case by case and under specific requirements that should be met cumulatively to provide additional value to healthcare's quality of service. The right conditions are created, the right benefits are amplified, public concerns are frequently assessed, private contributions are carefully considered, and all pressing challenges are managed by enhancing both public and private strengths. Leading decision- and action-making processes in corporate, governmental, and social sectors is the goal of managing PPP models.

11.
Sci Rep ; 13(1): 6206, 2023 04 17.
Article in English | MEDLINE | ID: mdl-37069257

ABSTRACT

There is a growing piece of evidence that artificial intelligence may be helpful in the entire prostate cancer disease continuum. However, building machine learning algorithms robust to inter- and intra-radiologist segmentation variability is still a challenge. With this goal in mind, several model training approaches were compared: removing unstable features according to the intraclass correlation coefficient (ICC); training independently with features extracted from each radiologist's mask; training with the feature average between both radiologists; extracting radiomic features from the intersection or union of masks; and creating a heterogeneous dataset by randomly selecting one of the radiologists' masks for each patient. The classifier trained with this last resampled dataset presented with the lowest generalization error, suggesting that training with heterogeneous data leads to the development of the most robust classifiers. On the contrary, removing features with low ICC resulted in the highest generalization error. The selected radiomics dataset, with the randomly chosen radiologists, was concatenated with deep features extracted from neural networks trained to segment the whole prostate. This new hybrid dataset was then used to train a classifier. The results revealed that, even though the hybrid classifier was less overfitted than the one trained with deep features, it still was unable to outperform the radiomics model.


Subject(s)
Artificial Intelligence , Prostatic Neoplasms , Male , Humans , Machine Learning , Prostatic Neoplasms/diagnostic imaging , Algorithms
12.
Article in English | MEDLINE | ID: mdl-37107882

ABSTRACT

During and in the aftermath of the COVID-19 pandemic, several works reflected on young people's physical and psychological health. The Dual Factor Model, which we refer to as the quadripartite model, is useful for understanding children's and adolescents' psychological health and differentiating them regarding their attitude toward the effects of the COVID-19 pandemic. In this investigation, students from the fifth to twelfth year of schooling enrolled in the DGEEC study "Psychological Health and Wellbeing in Portuguese schools" were considered. Four groups were created based on life satisfaction (low or high) and psychological distress (with or without symptoms). The study included 4444 students (M = 13.39 years ± 2.41), of whom 47.8% were male. Of the participants, 27.2% were in the second cycle of primary education, and 72.8% were in lower and upper secondary education. Differences in gender and education level (as a proxy for age) were observed. Additionally, when considering students' perceptions of changes in their lives following the COVID-19 pandemic (stayed the same, became worse, became better), these three groups were compared concerning personal and contextual variables, revealing significant differences at both the individual and contextual levels. Finally, the study discusses the influence of education and health professionals and the need for friendly public policies.


Subject(s)
COVID-19 , Child , Humans , Male , Adolescent , Female , COVID-19/epidemiology , Pandemics , Attitude , Mental Health , Personal Satisfaction
13.
Int J Health Plann Manage ; 38(4): 904-917, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36898975

ABSTRACT

OBJECTIVES: The emergency department (ED) is a very important healthcare entrance point, known for its challenging organisation and management due to demand unpredictability. An accurate forecast system of ED visits is crucial to the implementation of better management strategies that optimise resources utilization, reduce costs and improve public confidence. The aim of this review is to investigate the different factors that affect the ED visits forecasting outcomes, in particular the predictive variables and type of models applied. METHODS: A systematic search was conducted in PubMed, Web of Science and Scopus. The review methodology followed the PRISMA statement guidelines. RESULTS: Seven studies were selected, all exploring predictive models to forecast ED daily visits for general care. MAPE and RMAE were used to measure models' accuracy. All models displayed good accuracy, with errors below 10%. CONCLUSIONS: Model selection and accuracy was found to be particularly sensitive to the ED dimension. While ARIMA-based and other linear models have good performance for short-time forecast, some machine learning methods proved to be more stable when forecasting multiple horizons. The inclusion of exogenous variables was found to be advantageous only in bigger EDs.


Subject(s)
Emergency Service, Hospital , Models, Statistical , Linear Models , Forecasting , Hospitals
14.
Cancers (Basel) ; 15(5)2023 Feb 25.
Article in English | MEDLINE | ID: mdl-36900261

ABSTRACT

Prostate cancer is one of the most common forms of cancer globally, affecting roughly one in every eight men according to the American Cancer Society. Although the survival rate for prostate cancer is significantly high given the very high incidence rate, there is an urgent need to improve and develop new clinical aid systems to help detect and treat prostate cancer in a timely manner. In this retrospective study, our contributions are twofold: First, we perform a comparative unified study of different commonly used segmentation models for prostate gland and zone (peripheral and transition) segmentation. Second, we present and evaluate an additional research question regarding the effectiveness of using an object detector as a pre-processing step to aid in the segmentation process. We perform a thorough evaluation of the deep learning models on two public datasets, where one is used for cross-validation and the other as an external test set. Overall, the results reveal that the choice of model is relatively inconsequential, as the majority produce non-significantly different scores, apart from nnU-Net which consistently outperforms others, and that the models trained on data cropped by the object detector often generalize better, despite performing worse during cross-validation.

15.
Meat Sci ; 198: 109098, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36681060

ABSTRACT

Two groups of 8 individually housed young crossbred-bulls, in the finishing period, were used to test the effect of a Total Mixed Ration diet with high forage content (54% DM), low starch content (14% DM), supplemented with sunflower seeds (10% DM) (HFS) on growth performance, carcass and meat quality, fatty acid profile and carbon footprint, with reference to a conventional concentrate-based (90% DM) (Control) diet. The experiment lasted 64 days before slaughter. During the experiment, feed intake was monitored daily and live weight every 14 days. Individual CH4 emissions were assessed at 16-days intervals, using a GreenFeed for Large Animal unit. Feed intake and feed conversion ratio were higher for HFS diet, but average daily weight gain and feeding costs were similar for the two diets. Dressing percentage was reduced with HFS diet. The HFS increased redness, yellowness and Chroma of subcutaneous fat, but did not compromise commercial value of the carcasses. Meat colour, shear force, or sensory parameters were not affected by diet. The HFS diet allowed a healthier FA profile, due to the higher proportions of 18:3n-3, t11-18:1 and c9,t11-18:2 and the lower proportion of t10-18:1. The HFS diet did not reduce the carbon footprint in the finishing period of young bulls, due to increased digestive CH4 emissions. The results of this experiment showed that the HFS diet can be an alternative to the conventional diets used in finishing young-bulls. Although it may result in a slight reduction in animal performance, it has a strong impact on reducing dependence on inputs from outside the farm.


Subject(s)
Greenhouse Gases , Animals , Cattle , Male , Animal Feed/analysis , Diet/veterinary , Meat , Dietary Supplements
16.
Food Chem ; 398: 133945, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-35986990

ABSTRACT

Olive oils from seven Portuguese regions were selected to study the effect of the geographical origin on the oils' composition. Quality parameters, fatty acids, tocopherols, hydroxytyrosol and tyrosol derivatives, and oxidative stability were evaluated. All olive oils could be classified as extra virgin, and the geographical origin significantly affected the oils chemical composition. Principal component analysis further confirmed the significant impact of the geographical origin on the composition and, indirectly, on stability of the oils, showing that the evaluated parameters could be used as markers for geographical origin identification. Alternatively, Fourier transform infrared spectroscopy was applied, allowing to establish a linear discriminant model that correctly identified the geographical origin of the olive oils with a mean sensitivity of 99 ± 3 % (internal validation), confirming the impact of the oil origin on its characteristics. This finding allowed foreseeing the future application of the spectroscopy approach as a green, fast and non-invasive authentication tool.


Subject(s)
Galega , Fatty Acids/analysis , Olive Oil/chemistry , Plant Oils/chemistry , Spectroscopy, Fourier Transform Infrared , Tocopherols/chemistry
17.
Sensors (Basel) ; 24(1)2023 Dec 31.
Article in English | MEDLINE | ID: mdl-38203095

ABSTRACT

Defect detection is a key element of quality control in today's industries, and the process requires the incorporation of automated methods, including image sensors, to detect any potential defects that may occur during the manufacturing process. While there are various methods that can be used for inspecting surfaces, such as those of metal and building materials, there are only a limited number of techniques that are specifically designed to analyze specialized surfaces, such as ceramics, which can potentially reveal distinctive anomalies or characteristics that require a more precise and focused approach. This article describes a study and proposes an extended solution for defect detection on ceramic pieces within an industrial environment, utilizing a computer vision system with deep learning models. The solution includes an image acquisition process and a labeling platform to create training datasets, as well as an image preprocessing technique, to feed a machine learning algorithm based on convolutional neural networks (CNNs) capable of running in real time within a manufacturing environment. The developed solution was implemented and evaluated at a leading Portuguese company that specializes in the manufacturing of tableware and fine stoneware. The collaboration between the research team and the company resulted in the development of an automated and effective system for detecting defects in ceramic pieces, achieving an accuracy of 98.00% and an F1-Score of 97.29%.

18.
Sensors (Basel) ; 22(24)2022 Dec 09.
Article in English | MEDLINE | ID: mdl-36560020

ABSTRACT

The geographical traceability of extra virgin olive oils (EVOO) is of paramount importance for oil chain actors and consumers. Oils produced in two adjacent Portuguese regions, Côa (36 oils) and Douro (31 oils), were evaluated and fulfilled the European legal thresholds for EVOO categorization. Compared to the Douro region, oils from Côa had higher total phenol contents (505 versus 279 mg GAE/kg) and greater oxidative stabilities (17.5 versus 10.6 h). The majority of Côa oils were fruity-green, bitter, and pungent oils. Conversely, Douro oils exhibited a more intense fruity-ripe and sweet sensation. Accordingly, different volatiles were detected, belonging to eight chemical families, from which aldehydes were the most abundant. Additionally, all oils were evaluated using a lab-made electronic nose, with metal oxide semiconductor sensors. The electrical fingerprints, together with principal component analysis, enabled the unsupervised recognition of the oils' geographical origin, and their successful supervised linear discrimination (sensitivity of 98.5% and specificity of 98.4%; internal validation). The E-nose also quantified the contents of the two main volatile chemical classes (alcohols and aldehydes) and of the total volatiles content, for the studied olive oils split by geographical origin, using multivariate linear regression models (0.981 ≤ R2 ≤ 0.998 and 0.40 ≤ RMSE ≤ 2.79 mg/kg oil; internal validation). The E-nose-MOS was shown to be a fast, green, non-invasive and cost-effective tool for authenticating the geographical origin of the studied olive oils and to estimate the contents of the most abundant chemical classes of volatiles.


Subject(s)
Electronic Nose , Taste , Humans , Olive Oil/chemistry , Portugal , Aldehydes
19.
J Food Sci ; 87(12): 5363-5374, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36353800

ABSTRACT

Long-term transport and storage of peeled almonds under unsuitable conditions may cause the product's rejection. To get knowledge in this topic, peeled almonds were stored at 25°C and 60, 70, and 80% relative humidity (RH). The maintenance of high RH (80%) caused some visual defects after 4 months. Even though the 60, 70, and 80% RH did not clearly affect the production of primary and secondary products formed in the lipid oxidation during the 6 months of storage, sometimes an increase in the values of the specific extinction at the wavelength of 268 nm (K268 ) was observed at 80% RH, suggesting the occurrence to some extent of secondary oxidation. Concerning microbial counts, the almonds stored at 60 and 70% RH presented a satisfactory microbial quality until 6 months; however, at 80% RH, the mold counts were higher than the reference values after 2 months. Several mycotoxins were detected at low levels, including aflatoxins B1 and G1, although some showed higher amounts at 80% RH. In general, it is recommended that almond producers and industrials should consider the use of low RH (< 80%) for maritime transport and long-term storage of almond kernels. PRACTICAL APPLICATION: High levels of relative humidity during storage/transport of almond kernels favor fungal growth, mycotoxin production, and secondary oxidation (rancidity). It is recommended to keep the almond kernels under low RH (< 80%) in maritime transport and long storage, especially in tropical countries.


Subject(s)
Mycotoxins , Prunus dulcis , Humidity , Oxidation-Reduction , Fungi
20.
Eur J Med Chem ; 244: 114794, 2022 Dec 15.
Article in English | MEDLINE | ID: mdl-36252395

ABSTRACT

Age-related neurodegenerative diseases have in common the occurrence of cognitive impairment, a highly incapacitating process that involves the cholinergic neurotransmission system. The vesicular acetylcholine transporter (VAChT) positron emission tomography (PET) tracer [18F]fluoroethoxybenzovesamicol ((-)-[18F]FEOBV) has recently demonstrated its high value to detect alterations of the cholinergic system in Alzheimer's disease, Parkinson's disease and dementia with Lewy body. We present here the development of the new vesamicol derivative tracer (-)-(R,R)-5-[18F]fluorobenzovesamicol ((-)[18F]FBVM) that we compared to (-)[18F]FEOBV in the same experimental conditions. We show that: i) in vitro affinity for the VAChT was 50-fold higher for (-)FBVM (Ki = 0.9 ± 0.3 nM) than for (-)FEOBV (Ki = 61 ± 2.8 nM); ii) in vivo in rats, a higher signal-to-noise specific brain uptake and a lower binding to plasma proteins and peripheral defluorination were obtained for (-)[18F]FBVM compared to (-)[18F]FEOBV. Our findings demonstrate that (-)[18F]FBVM is a highly promising PET imaging tracer which could be sufficiently sensitive to detect in humans the cholinergic denervation that occurs in brain areas having a low density of VAChT such as the cortex and hippocampus.


Subject(s)
Positron-Emission Tomography , Tomography, X-Ray Computed , Humans , Animals , Rats , Vesicular Acetylcholine Transport Proteins/metabolism , Positron-Emission Tomography/methods , Brain/diagnostic imaging , Brain/metabolism , Cholinergic Agents
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