109 research outputs found
Tissue Microarray Analysis Applied to Bone Diagenesis
Taphonomic processes affecting bone post mortem are important in forensic, archaeological and palaeontological investigations. In this study, the application of tissue microarray (TMA) analysis to a sample of femoral bone specimens from 20 exhumed individuals of known period of burial and age at death is described. TMA allows multiplexing of subsamples, permitting standardized comparative analysis of adjacent sections in 3-D and of representative cross-sections of a large number of specimens. Standard hematoxylin and eosin, periodic acid-Schiff and silver methenamine, and picrosirius red staining, and CD31 and CD34 immunohistochemistry were applied to TMA sections. Osteocyte and osteocyte lacuna counts, percent bone matrix loss, and fungal spheroid element counts could be measured and collagen fibre bundles observed in all specimens. Decalcification with 7 % nitric acid proceeded more rapidly than with 0.5 M EDTA and may offer better preservation of histological and cellular structure. No endothelial cells could be detected using CD31 and CD34 immunohistochemistry. Correlation between osteocytes per lacuna and age at death may reflect reported age-related responses to microdamage. Methodological limitations and caveats, and results of the TMA analysis of post mortem diagenesis in bone are discussed, and implications for DNA survival and recovery considered
Asymmetric c-fos expression in the ventral orbital cortex is associated with impaired reversal learning in a right-sided neuropathy
BACKGROUND:
Recently we showed that unilateral peripheral neuropathic lesions impacted differentially on rat's emotional/cognitive behavior depending on its left/right location; importantly, this observation recapitulates clinical reports. The prefrontal cortex (PFC), a brain region morphofunctionally affected in chronic pain conditions, is involved in the modulation of both emotion and executive function and displays functional lateralization. To test whether the PFC is involved in the lateralization bias associated with left/right pain, c-fos expression in medial and orbital areas was analyzed in rats with an unilateral spared nerve injury neuropathy installed in the left or in the right side after performing an attentional set-shifting, a strongly PFC-dependent task.
RESULTS:
SNI-R animals required more trials to successfully terminate the reversal steps of the attentional set-shifting task. A generalized increase of c-fos density in medial and orbital PFC (mPFC/OFC), irrespectively of the hemisphere, was observed in both SNI-L and SNI-R. However, individual laterality indexes revealed that contrary to controls and SNI-L, SNI-R animals presented a leftward shift in c-fos density in the ventral OFC (VO). None of these effects were observed in the neighboring primary motor area.
CONCLUSIONS:
Our results demonstrate that chronic neuropathic pain is associated with a bilateral mPFC and OFC hyperactivation. We hypothesize that the impaired performance of SNI-R animals is associated with a left/right activity inversion in the VO, whose functional integrity is critical for reversal learning.This work was granted by the Portuguese Science Foundation (FCT) project PTDC/SAU-NEU/108557/2008 and grant SFRH/BPD/80118/2011
ANÁLISE DA GESTÃO DAS UNIDADES DE CONSERVAÇÃO DO SISTEMA ESTADUAL DE ÁREAS PROTEGIDAS DE MINAS GERAIS
Conservation Units (UC) are especially protected areas for the protection of natural resources. Minas Gerais state shelter various UC created by the various levels of government. This study aimed to identify and discuss aspects of management currently undertaken by the State System of Protected Areas of Minas Gerais (SEAP), as well as its advances, trends and obstacles, especially related to: cycle management and monitoring of results, levels of strategic management and operational; agreement results, the State Program for Results; Deployment System Management of Protected Areas - SIGAP, planning tools, relationship to the community and popular participation, human resources policy, management shared, policy cost and financing activities and bottlenecks of the process of managing the State System of Protected Areas - SEAP. The methodology used was a semi-structured interviews and questionnaires applied to all managers of UC. The results showed that the use of planning tools and management of SEAP were effective in the opinion of managers. However, they were still appointed, as limitations of the efficiency of the management of UC, the lack of infrastructure and human resources. Co-management of UC with partner institutions shows to be appropriate and promising.As Unidades de Conservação (UC) são espaços territoriais especialmente protegidos para a proteção dos recursos naturais. Minas Gerais abriga UC criadas pelos vários níveis de governo. O trabalho objetivou identificar e discutir os aspectos da gestão atualmente realizados pelo Sistema Estadual de Áreas Protegidas de Minas Gerais (SEAP), assim como seus avanços, tendências e entraves, especialmente sobre: ciclo de gestão e monitoramento de resultados; níveis de gestão estratégica e operacional; acordo de Resultados; Programa do Estado para Resultados; implantação do Sistema de Gestão de Áreas Protegidas (SIGAP); ferramentas de planejamento; relação com a comunidade e participação popular; política de recursos humanos; gestão compartilhada; política de custeio e financiamento de atividades e gargalos do processo de gestão do SEAP. A metodologia utilizada foi a de entrevistas semi-estruturadas e questionários aplicados a todos os gerentes de UC. Os resultados mostraram que o uso de ferramentas de planejamento e gestão do SEAP, na opinião dos gerentes, foi eficiente. No entanto, ainda foram apontados, como limitações da eficiência da gestão das UC, a falta de infra-estrutura e de recursos humanos. A co-gestão das UC com instituições parceiras mostra-se adequada e promissora
Evidence for lack of direct causality between pain and affective disturbances in a rat peripheral neuropathy model
[Epub ahead of print]Chronic pain is frequently accompanied by the manifestation of emotional disturbances and cognitive deficits. While a causality relation between pain and emotional/cognitive disturbances is generally assumed, several observations suggest a temporal dissociation and independent mechanisms. We therefore studied Sprague-Dawley rats that presented a natural resistance to pain manifestation in a neuropathy model (spared nerve injury [SNI]) and compared their performance in a battery of behavioral paradigms-anxiety, depression and fear memory-with animals that presented a pain phenotype. Afterward, we performed an extensive volumetric analysis across prefrontal, orbitofrontal and insular cortical areas. The majority of SNI animals manifested mechanical allodynia (low threshold [LT]), but 13% were similar to Sham controls (high threshold [HT]). Readouts of spontaneous hypersensivity (paw flinches) were also significantly reduced in HT and correlated with allodynia. To increase the specificity of our findings, we segregated the SNI animals in those with left (SNI-L) and right (SNI-R) lesions and the lack of association between pain and behavior still remains. Left-lesioned animals, independent of the LT or HT phenotype, presented increased anxiety-like behaviors and decreased well-being. In contrast, we found that the insular cortex (agranular division) was significantly smaller in HT than in LT. To conclude, pain and emotional disturbances observed following nerve injury are to some extent segregated phenomena. Also, HT and LT SNI presented differences in insular volumes, an area vastly implicated in pain perception, suggesting a supraspinal involvement in the manifestation of these phenotypes.This work has been funded by the European Regional Development Fund (FEDER),
through the Competitiveness Factors Operational Programme (COMPETE) and the
Northern Portugal Regional Operational Programme (NORTE 2020) under the
Portugal 2020 Partnership Agreement (project NORTE-01-0145-FEDER-000023). It
was also funded by National and International funds, through the Foundation for
Science and Technology (FCT), under the scope of the projects POCI-01-0145-
FEDER-007038 and PTDC/NEU-SCC/5301/2014 and by the IASP Early Career
Research Grant 2015.
Researchers were supported by FCT grant numbers PD/BD/114117/2015 (MRG via
Inter-University Doctoral Programme in Ageing and Chronic Disease, PhDOC),
SFRH/BD/109111/2015 (AMC via PhD Program in Health Sciences),
SFRH/BD/52291/2013 (ME via PhDOC), SFRH/BD/89936/2012 (SB via PhD
Program in Health Sciences (Applied)), PDE/BDE/113604/2015 (RM via PhD
Program in Health Sciences (Applied)), PDE/BDE/113601/2015 (PSM via PhD
Program in Health Sciences (Applied)) and SFRH/BPD/80118/2011 (HA). ARS
integrated the Master Programme in Health Sciences of the School of Medicine,
University of Minho.info:eu-repo/semantics/acceptedVersio
Acupuncture at “Zusanli” (St.36) and “Sanyinjiao” (SP.6) Points on the Gastrointestinal Tract: A Study of the Bioavailability of 99mTc-Sodium Pertechnetate in Rats
The objective of this study is to investigate the differences of acupuncture effect between the Zusanli (St.36) and Sanyinjiao (SP.6) points on the gastrointestinal-tract (GIT) segment performed by the bioavailability of
99mTc-sodium-pertechnetate (Na99mTcO4) in rats. Male Wistar rats (n = 21) were allocated into three groups of seven each. Group 1 was treated by acupuncture bilaterally at St.36; Group 2 at SP.6; and Group 3 was untreated (control). After 10 min of needle insertion in anesthetized rats, 0.3 mL of Na99mTcO4 (7.4 MBq) was injected via ocular-plexus. After 20 min, the exitus of animals was induced by cervical-dislocation and GIT organs isolated. However, immediately before the exitus procedure, blood was collected by cardiac-puncture for blood radio-labeling (BRL). The radioactivity uptake of the blood constituents was calculated together with the GIT organs by a well gamma counter. The percentage of injected dose per gram of tissue (%ID/g) of Na99mTcO4 was calculated for each GIT organs, while BRL was calculated in %ID. According to the one-way ANOVA, the stomach, jejunum, ileum from the treated groups (Group 1 and Group 2) had significant differences compared to the controls (Group 3). However, between the treated groups (Group 1 and Group 2), there were significant differences (P < .05) in the stomach, jejunum, ileum, cecum, transverse and rectum. In BRL analysis, Group 2 showed significant increase and decrease of the insoluble and soluble fractions of the blood cells, respectively (P < .0001). The authors suggest that St.36 may have a tendency of up-regulation effect on GIT, whereas SP.6, down-regulation effect. However, further rigorous experimental studies to examine the effectiveness of acupuncture in either acupuncture points need to be carried out
Absence of Tau triggers age-dependent sciatic nerve morphofunctional deficits and motor impairment
Dementia is the cardinal feature of Alzheimer's disease (AD), yet the clinical symptoms of this disorder also include a marked loss of motor function. Tau abnormal hyperphosphorylation and malfunction are well-established key events in AD neuropathology but the impact of the loss of normal Tau function in neuronal degeneration and subsequent behavioral deficits is still debated. While Tau reduction has been increasingly suggested as therapeutic strategy against neurodegeneration, particularly in AD, there is controversial evidence about whether loss of Tau progressively impacts on motor function arguing about damage of CNS motor components. Using a variety of motor-related tests, we herein provide evidence of an age-dependent motor impairment in Tau-/- animals that is accompanied by ultrastructural and functional impairments of the efferent fibers that convey motor-related information. Specifically, we show that the sciatic nerve of old (17-22-months) Tau-/- mice displays increased degenerating myelinated fibers and diminished conduction properties, as compared to age-matched wild-type (Tau+/+) littermates and younger (4-6months) Tau-/- and Tau+/+ mice. In addition, the sciatic nerves of Tau-/- mice exhibit a progressive hypomyelination (assessed by g-ratio) specifically affecting large-diameter, motor-related axons in old animals. These findings suggest that loss of Tau protein may progressively impact on peripheral motor system.The work was supported by grants 'PTDC/SAU-NMC/113934/2009,' 'PTDC/SAU-NSC/118194/2010,' 'SFRH/BPD/97281/2013,' PTDC/SAU-NSC/118194/2010,' 'SFRH/BPD/80118/2011,' 'SFRH/BD/89714/2012' funded by FCT-Portuguese Foundation for Science and Technology and project DoIT-Desenvolvimento e Operacionalizacao da Investigacao de Translacao (No do projeto 13853), funded by Fundo Europeu de Desenvolvimento Regional (FEDER) throughout the Programa Operacional Fatores de Competitividade (POFC). In addition, this work was also co-financed by European Union FP7 project SwitchBox (NS) and the Portuguese North Regional Operational Program (ON.2 - O Novo Norte) under the National Strategic Reference Framework (QREN), through the European Regional Development Fund (FEDER).info:eu-repo/semantics/publishedVersio
Bias and unfairness in machine learning models: a systematic literature review
One of the difficulties of artificial intelligence is to ensure that model
decisions are fair and free of bias. In research, datasets, metrics,
techniques, and tools are applied to detect and mitigate algorithmic unfairness
and bias. This study aims to examine existing knowledge on bias and unfairness
in Machine Learning models, identifying mitigation methods, fairness metrics,
and supporting tools. A Systematic Literature Review found 40 eligible articles
published between 2017 and 2022 in the Scopus, IEEE Xplore, Web of Science, and
Google Scholar knowledge bases. The results show numerous bias and unfairness
detection and mitigation approaches for ML technologies, with clearly defined
metrics in the literature, and varied metrics can be highlighted. We recommend
further research to define the techniques and metrics that should be employed
in each case to standardize and ensure the impartiality of the machine learning
model, thus, allowing the most appropriate metric to detect bias and unfairness
in a given context
Agronomic and environmental aspects of organo-mineral fertilizers produced with a by-product of the intermediate process of tanning
IntroductionThe by-product of the intermediate process of tanning (BPIPT) can be used in the manufacturing of environmentally-friendly organo-mineral fertilizers (OMF). However, the presence of potentially toxic elements (e.g., chromium, Cr), can hinder the use of BPIPT in agriculture. This study aimed: i) to evaluate soil chemical and biological properties following the application of fertilizers produced with a BPIPT, in contrast to other OMF produced with traditional organic matrices; and ii) to assess the impacts of such products on wheat growth and nutrition.MethodsSamples (0-0.2 m) of two Oxisols [Red-Yellow Latosol (LVAd) and Red Latosol (LVd)] were used in this study, consisting of two experiments (with five treatments and five replicates) using different OMF, in a sequence: 1) incubation of fertilizers in soil samples for 30 days, and 2) wheat cultivation (30 days) after the fertilizer incubation. The treatments consisted of an arrangement of mineral fertilizers based on nitrogen, phosphorus, and potassium (NPK fertilizers), associated with OMF based on BPIPT (OM-IPT and OM-IPT+S) or commercial manure (OM-CM and OM-CM+S), with or without sulfur (S), and a control treatment. Elemental availability in soils and microbial attributes were determined after the incubation of the OMF in the soils. After wheat cultivation, plant biomass, nutritional composition, β-glucosidase activity, and fluorescein diacetate hydrolysis (FDA) were measured.Results and discussionThe application of BPIPT-derived OMF in the present study increased available Cr fraction contents in both soils. However, OM-IPT caused low soil acidification, enhanced wheat growth and nutrition, and stimulated microbial activity in soils (FDA and β-glucosidase), thus evidencing the agronomic and environmental benefits of this OMF and their potential to contribute to a cleaner, more sustainable agriculture
Checklist of the dipterofauna (Insecta) from Roraima, Brazil, with special reference to the Brazilian Ecological Station of Maracá
Roraima is a Brazilian state located in the northern portion of the Amazon basin, with few studies regarding its biodiversity. The Ecological Station of Maracá (Brazil, state of Roraima) harbors the third largest Brazilian pluvial island and is composed of a transitional landscape of savanna and Amazon rainforest components. Despite its ecological importance and strategic localization, few studies covered the dipterofauna of this locality. An updated checklist addressing 41 families of true flies (Diptera) occurring in Roraima is presented based on the literature and the specimens collected during a field expedition that occurred in 2015. This checklist brings several improvements such as new records of 165 taxa to the state of Roraima, 29 taxa to Brazil, and 259 morphotypes, mostly likely representing undescribed species
Perfil e percepção dos chefes de unidades de conservação do sistema estadual de áreas protegidas em Minas Gerais
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