Quality of seed potato tubers treated with paraquat and the development of a simplified methodology for paraquat residue detection

O objetivo desse trabalho foi avaliar a qualidade de tubérculos de batatas-semente (Solanum tuberosum) tratados com paraquat e desenvolver uma metodologia simplificada de detecção de resíduos de herbicida. Dois ensaios foram realizados no Laboratório da Ciência das Plantas Daninhas do Centro Nacional de Pesquisa de hortaliças, Brasília, DF. No experimento, tubérculos das cultivares Achat e Baronesa foram submersos em soluções de 0 e 200 ppm de paraquat ou injetados com 0,5 ml de soluções de 0 e 200 ppm do herbicida. O delineamento experimental foi inteiramente casualizado com 8 repetições e 12 tubérculos por parcela. Os tubérculos foram colocados em câmara fria, após a aplicação com paraquat, para quebra da dormência. Após a brotação dos tubérculos avaliou-se a qualidade interna dos mesmos, amostrando, posteriormente, 2 tubérculos de cada parcela para o plantio em vasos, sob condições de telado, para verificar possíveis danos no crescimento das plantas oriundas dos tubérculos tratados. Os tratamentos de imersão não provocaram, aparentemente, nenhum dano interno nos tubérculos, ou nem mesmo afetaram a nova geração, entretanto, os tubérculos injetados com paraquat foram severamente deteriorados e carbonizados, originando plantas bastante debilitadas. Esses resultados indicam que quando o paraquat for aplicado sob condições que favoreçam sua penetração ou translocação para o interior do tubérculo, atingindo os vasos e a polpa, pode danificá-lo severamente, prejudicar sua aparência, qualidade de produção e reduzir o desenvolvimento da nova geração de plantas oriundas dos tubérculos contaminados . No segundo experimento, desenvolveu-se uma metodologia simplificada para detectar resíduos de paraquat nos tubérculos através de colorimetria, visto que o paraquat é reduzido a um radical de cor azul na presença de ditionito de sódio (Na2S2O4) a 1% em meio básico, a qual se intensifica à medida que a concentração do produto aumenta. A metodologia simplificada desenvolvida permitiu detectar resíduos de paraquat ao nível de 0,06 ppm, indicando uma excelente aproximação, pois, o limite de tolerância do paraquat em tubérculos de batata é de 0,2 ppm, normalmente, determinado pelo método analítico completo, que apresenta limites de detecção em torno de 0,01 ppm e recuperação acima de 70%. Uma avaliação qualitativa da concentração residual de produto nas amostras foi possível através de leitura e comparações visuais entre os diferentes graus de cores desenvolvidas nas soluções visuais entre os diferentes graus de cores desenvolvidas nas soluções padrão e a cor desenvolvida na amostra, não necessitando, portanto, das leituras colorimétricas, podendo ser feita inclusive no campo. Observou-se que a maioria do paraquat permaneceu na região de casca até o período de 4 semanas após a aplicação do paraquat.Seed potatoes tubers (Solanum tuberosum) of two cultivars (Achat and Baronesa) were treated with paraquat solutions to evalute the internal tuber quality and to detect its residue by a simplified methodology. Two experiments were carried out at the National Research Center on Vegetables, Brasília, DF. In experiment one some tubers were immersed in 0 and 200 ppm of paraquat solutions and others were injected with 0,5 ml of 0 and 200 ppm solutions of the herbicide. Twelve tubers were used as plot in a complete randomized design with 8 replications. The internal tuber quality was evaluated after breaking dormancy and sprouting of ten tubers. Also, two tubers were sampled and put in 5 liter pots and grown under greenhouse conditions to observe if the herbicide would affect the growth of the new plant generation. The immersion treatments did not cause any internal damage to the tubers nor did they affect the new plant generation; however, tubers injected with paraquat were severely damaged (carbonization). Also, the next plant generation was affected and the surviving plants were small and not vigorus. These results indicate that paraquat can severely damage those tubers that absorbed and/or translocated the herbicide. In experiment two a simplified methodology to detect paraquat residue in the tubers was set up by colorimetric means. Paraquat was reduced with sodium dithionite (Na2S2O4) in basic solution to a blue radical ion whitch intensified its color with any increase in paraquat concentration. The development of this simplified methodology alowed the detection of paraquat residue above 0,06 ppm, indicating na excellent sensitivity and recovery in comparison with the residue analytical procedure of this herbicide, with a limit of detectability of about 0,01 ppm in crop samples of 200g. In addition to the quantitative determination of paraquat, this methodology allwos to determine qualitatively paraquat concentration by colour comparisons. Most of the paraquat residue was determined from potato skins up to 4 weeks after paraquat application

Barriers to cardiac rehabilitation delivery in a low-resource setting from the perspective of healthcare administrators, rehabilitation providers, and cardiac patients

Background: Despite clinical practice guideline recommendations that cardiovascular disease patients participate, cardiac rehabilitation (CR) programs are highly unavailable and underutilized. This is particularly true in low-resource settings, where the epidemic is at its’ worst. The reasons are complex, and include health system, program and patient-level barriers. This is the first study to assess barriers at all these levels concurrently, and to do so in a lowresource setting. Methods: In this cross-sectional study, data from three cohorts (healthcare administrators, CR coordinators and patients) were triangulated. Healthcare administrators from all institutions offering cardiac services, and providers from all CR programs in public and private institutions of Minas Gerais state, Brazil were invited to complete a questionnaire. Patients from a random subsample of 12 outpatient cardiac clinics and 11 CR programs in these institutions completed the CR Barriers Scale. Results: Thirty-two (35.2%) healthcare administrators, 16 (28.6%) CR providers and 805 cardiac patients (305 [37.9%] attending CR) consented to participate. Administrators recognized the importance of CR, but also the lack of resources to deliver it; CR providers noted referral is lacking. Patients who were not enrolled in CR reported significantly greater barriers related to comorbidities/functional status, perceived need, personal/family issues and access than enrollees, and enrollees reported travel/work conflicts as greater barriers than non-enrollees (all p < 0.01). Conclusions: The inter-relationship among barriers at each level is evident; without resources to offer more programs, there are no programs to which physicians can refer (and hence inform and encourage patients to attend), and patients will continue to have barriers related to distance, cost and transport. Advocacy for services is needed. Keywords: Health care services, Cardiac rehabilitation, Cardiac care facilities, Attitude of health personnelYork University Librarie

Electrochemical miRNA-34a-based biosensor for the diagnosis of Alzheimer’s disease

Alzheimer's disease (AD) is the most common dementia type and a leading cause of death and disability in the elderly. Diagnosis is expensive and invasive, urging the development of new, affordable, and less invasive diagnostic tools. The identification of changes in the expression of non-coding RNAs prompts the development of diagnostic tools to detect disease-specific blood biomarkers. Building on this idea, this work reports a novel electrochemical microRNA (miRNA) biosensor for the diagnosis of AD, based on carbon screen-printed electrodes (C-SPEs) modified with two gold nanostructures and a complementary anti-miR-34a oligonucleotide probe. This biosensor showed good target affinity, reflected on a 100 pM to 1 M linearity range and a limit of detection (LOD) of 39 pM in buffer and 94 aM in serum. Moreover, the biosensors response was not affected by serum compounds, indicating selectivity for miR-34a. The biosensor also detected miR-34a in the cell culture medium of a common AD model, stimulated with a neurotoxin to increase miR-34a secretion. Overall, the proposed biosensor makes a solid case for the introduction of a novel, inexpensive, and minimally invasive tool for the early diagnosis of AD, based on the detection of a circulating miRNA overexpressed in this pathology.This work was supported by 0624_2IQBIONEURO_6_E, 2IQBioneuro, Promotion of an R&I network in biological chemistry for the diagnosis and treatment of neurological diseases EP-INTERREG V Spain Portugal (POCTEP), and by Portuguese funds through FCT in the framework of the project PTDC/BTM-MAT/4156/2021. S.D.S acknowledges FCT (Fundação para a Ciência e a Tecnologia, I.P.) for her contract under the Norma Transitória – DL57/2016/CP/CP1360/CT0013.info:eu-repo/semantics/publishedVersio

The Membrane QmoABC Complex Interacts Directly with the Dissimilatory Adenosine 5′-Phosphosulfate Reductase in Sulfate Reducing Bacteria

The adenosine 5′-phosphosulfate reductase (AprAB) is the enzyme responsible for the reduction of adenosine 5′-phosphosulfate (APS) to sulfite in the biological process of dissimilatory sulfate reduction, which is carried out by a ubiquitous group of sulfate reducing prokaryotes. The electron donor for AprAB has not been clearly identified, but was proposed to be the QmoABC membrane complex, since an aprBA–qmoABC gene cluster is found in many sulfate reducing and sulfur-oxidizing bacteria. The QmoABC complex is essential for sulfate reduction, but electron transfer between QmoABC and AprAB has not been reported. In this work we provide the first direct evidence that QmoABC and AprAB interact in Desulfovibrio spp., using co-immunoprecipitation, cross-linking Far-Western blot, tag-affinity purification, and surface plasmon resonance studies. This showed that the QmoABC–AprAB complex has a strong steady-state affinity (KD = 90 ± 3 nM), but has a transient character due to a fast dissociation rate. Far-Western blot identified QmoA as the Qmo subunit most involved in the interaction. Nevertheless, electron transfer from menaquinol analogs to APS through anaerobically purified QmoABC and AprAB could not be detected. We propose that this reaction requires the involvement of a third partner to allow electron flow driven by a reverse electron bifurcation process, i.e., electron confurcation. This process is deemed essential to allow coupling of APS reduction to chemiosmotic energy conservation

Hydroxyapatite/alginate/gellan gum inks with osteoconduction and osteogenic potential for bioprinting bone tissue analogues

There is a growing demand for engineered bone tissues custom-designed to match the patient-specific defect size and in vitro models for studying bone diseases and/or drug screening. Herein, we propose a bioprinted bone tissue construct using SaOs-2 cells within alginate/gellan gum/hydroxyapatite inks. Different ink formulations were developed with varying hydroxyapatite content and then evaluated for viscoelasticity, printability, biomineralization properties, post-printing viability, proliferation, metabolic activity, and osteogenic phenotype of SaOs-2-encapsulated cells. Results indicate that ink formulations exhibit non-Newtonian shear-thinning behaviour, maintaining shape integrity and structural stability post-printing. Ink mineralization rates increase with the hydroxyapatite content, rendering them suitable for bone defect strategies. Post-printed cells in the developed constructs remain live, spreading, and metabolically active but do not proliferate. Osteogenic gene and protein expression, both early and late, show upregulation at day 7 relative to day 1, followed by downregulation at day 14. Lower hydroxyapatite content inks demonstrate up to fourfold upregulation in genes and proteins at most time points. Additionally, these constructs release calcium and phosphate at levels conducive to mineralization. Overall, the tissue-engineered miniaturized constructs not only meet the criteria for early-stage bone defect/fracture regeneration but also serve as a promising platform for drug screening and evaluating potential therapeutic treatments.info:eu-repo/semantics/publishedVersio

Synthesis and cytotoxicity assessment of citrate-coated calcium and manganese ferrite nanoparticles for magnetic hyperthermia

Calcium-doped manganese ferrite nanoparticles (NPs) are gaining special interest in the biomedical field due to their lower cytotoxicity compared with other ferrites, and the fact that they have improved magnetic properties. Magnetic hyperthermia (MH) is an alternative cancer treatment, in which magnetic nanoparticles promote local heating that can lead to the apoptosis of cancer cells. In this work, manganese/calcium ferrite NPs coated with citrate (CaxMn1−xFe2O4 (x=0, 0.2, 1), were synthesized by the sol-gel method, followed by calcination, and then characterized regarding their crystalline structure (by X-ray diffraction, XRD), size and shape (by Transmission Electron Microscopy, TEM), hydrodynamic size and zeta potential (by Dynamic Light Scattering, DLS), and heating efficiency (measuring the Specific Absorption Rate, SAR, and Intrinsic Loss Power, ILP) under an alternating magnetic field. The obtained NPs showed a particle size within the range of 10 nm to 20 nm (by TEM) with a spherical or cubic shape. Ca0.2Mn0.8Fe2O4 NPs exhibited the highest SAR value of 36.3 W/g at the lowest field frequency tested, and achieved a temperature variation of ~7 °C in 120 s, meaning that these NPs are suitable magnetic hyperthermia agents. In vitro cellular internalization and cytotoxicity experiments, performed using the human cell line HEK 293T, confirmed cytocompatibility over 0–250 µg/mL range and successful internalization after 24 h. Based on these studies, our data suggest that these manganese-calcium ferrite NPs have potential for MH application and further use in in vivo systems.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of CEB (UIDB/04469/2020), CBMA (UIDB/04050/2020) and CF-UM-UP (UIDB/04650/2020) units. R.G.D. Andrade and S.R.S. Veloso acknowledge FCT for the PhD grants 2020.05781.BD and SFRH/BD/144017/2019, respectively.info:eu-repo/semantics/publishedVersio

Intergroup Emotions, Perceived Threats and Hostility against Foreigners: Comparing Brazil, Portugal, and Spain

This study analyzed whether hostility towards foreigners perceived as competitors in the labor market would be related to the perception of threat (symbolic and economic) and negative intergroup emotions. 270 people between 18 and 63 years participated. In Brazil (N = 89), mostly men (59%) and average age 32.5 years; In Portugal (N = 87), mostly men (56.3%) and average age 39.9 years; in Spain (N = 94), mostly women (53.2%) and average age of 32.8 years. The results (t-test, analysis of variance and multiple regressions) indicated that in Spain negative emotions are associated with less hostility towards immigrants; In Brazil, positive emotions are associated with hostile attitudes. In Portugal, the relationship between positive emotions and hostility is positive, but not signifi cant. The symbolic threat was the best predictor of hostility only in the Brazilian sample. Positive emotions predispose to a greater kindness towards foreigners in the three countries. The main conclusion of the study is that the economic crisis does not seem to be associated with the perception of competitiveness of foreigners in the local labor market and hostility towards this social group.O estudo analisou se a hostilidade para com estrangeiros percebidos como concorrentes no mercado de trabalho estaria relacionada com a percepção de ameaça (simbólica e econômica) e as emoções intergrupais negativas. Participaram 270 pessoas entre 18 e 63 anos, assim distribuídas: Brasil (N = 89), idade média de 32.5 anos, maioria de homens (59%); Portugal (N = 87), idade média de 39.9 anos, maioria de homens (56.3%); e Espanha (N=94), idade média de 32.8 anos, maioria de mulheres (53.2%). Os resultados do Teste-t, análise da variância e regressões múltiplas indicaram que enquanto na Espanha emoções negativas se associam a menos hostilidade para com imigrantes, no Brasil é a expressão de emoções positivas que se encontra associada a tais atitudes hostis. Em Portugal a relação entre emoções positivas e hostilidade é positiva, mas não signifi cativa. A ameaça simbólica foi o melhor preditor de hostilidade somente na amostra brasileira. Emoções positivas predizem maior amabilidade para com estrangeiros nas amostras dos três países. A principal conclusão do estudo é que a crise econômica não parece estar associada com a percepção de competitividade do estrangeiro no mercado de trabalho local e a hostilidade para com este grupo social.info:eu-repo/semantics/publishedVersio

Doenças primárias da pele e manifestações cutâneas de doenças sistêmicas em suínos

Skin diseases in pigs can negatively impact the production. They cause losses related to the death of the affected pigs, to the cost with the treatment, growth retardation and condemnations in the slaughterhouses. This study was developed to determine the frequency and describe the histopathological findings of skin diseases in pigs in different age groups through a retrospective study from 2006 to 2018. A total of 154 conclusive cases were analyzed, including skin restricted diseases (allergic dermatitis, exudative epidermitis, vesicular dermatitis, pityriasis rosea, swinepox, follicular cyst, papilloma and scrotal hemangioma) or skin lesions secondary to systemic diseases (erysipelas, porcine dermatitis and nephropathy syndrome [PDNS], bacterial septicemia and multiple hemorrhages without definite cause). The skin lesions were classified as bacterial (46.1%), viral (26.6%), allergic (12.3%), neoplastic (1.3%) and others (13.6%). Swine erysipelas was the most frequent diagnosis (47/154), followed by PDNS (23/154), allergic dermatitis (19/154) and exudative epidermitis (15/154). Vesicular dermatitis (9/154), pityriasis rosea (9/154), septicemia with cutaneous manifestations (9/154), swinepox (9/154) and multiple hemorrhages without definite cause (7/154) were also observed. Follicular cyst (3/154), hyperkeratosis without definite cause (2/154), papilloma (1/154), and scrotal hemangioma (1/154) were less frequently described. Of the conclusive diagnosis, age was reported in 138 cases, with the highest frequency of skin lesions observed at the inspection process during slaughter (56/138).As doenças de pele em suínos podem impactar negativamente a produção. Estas causam perdas relacionadas à morte dos acometidos, a custo com tratamentos, atraso no crescimento e condenações nos frigoríficos. Este trabalho foi desenvolvido para determinar a frequência e descrever os achados histopatológicos das doenças de pele em suínos nas diferentes faixas etárias, através de um estudo retrospectivo no período de 2006 a 2018. Foram analisados 154 casos conclusivos, incluindo as doenças restritas a pele (dermatites alérgicas, epidermite exsudativa, dermatite vesicular, pitiríase rósea, varíola suína, cisto folicular, papiloma e hemangioma escrotal) e as secundárias a doenças sistêmicas (erisipela, síndrome dermatite nefropatia suína [SDNS], septicemia bacteriana e hemorragias múltiplas de causa não determinada). Estas foram classificadas em bacterianas (46,1%), virais (26,6%), alérgicas (12,3%), neoplásicas (1,3%) e outras (13,6%). A erisipela suína foi a enfermidade mais diagnosticada (47/154), seguida por SDNS (23/154), dermatite alérgica (19/154) e epidermite exsudativa (15/154). Observamos ainda dermatite vesicular (9/154), pitiríase rósea (9/154), septicemia bacteriana com manifestações cutâneas (9/154), varíola suína (9/154) e hemorragias múltiplas de causa não determinada (7/154). Em menor número, cisto folicular (3/154), hiperqueratose sem causa definida (2/154), papiloma (1/154) e hemangioma escrotal (1/154). Dos casos conclusivos, a idade foi informada em 138 casos, sendo a maior frequência das lesões de pele observadas na linha de inspeção, durante o abate (56/138)

Circular economyeast: saccharomyces cerevisiae as a sustainable source of glucans and its safety for skincare application

Glucans, a polysaccharide naturally present in the yeast cell wall that can be obtained from side streams generated during the fermentation process, have gained increasing attention for their potential as a skin ingredient. Therefore, this study focused on the extraction method to isolate and purify water-insoluble glucans from two different Saccharomyces cerevisiae strains: an engineered strain obtained from spent yeast in an industrial fermentation process and a wild strain produced through lab-scale fermentation. Two water-insoluble extracts with a high glucose content (> 90 %) were achieved and further subjected to a chemical modification using carboxymethylation to improve their water solubility. All the glucans' extracts, water-insoluble and carboxymethylated, were structurally and chemically characterized, showing almost no differences between both yeast-type strains. To ensure their safety for skin application, a broad safety assessment was undertaken, and no cytotoxic effect, immunomodulatory capacity (IL-6 and IL-8 regulation), genotoxicity, skin sensitization, and impact on the skin microbiota were observed. These findings highlight the potential of glucans derived from spent yeast as a sustainable and safe ingredient for cosmetic and skincare formulations, contributing to the sustainability and circular economy.info:eu-repo/semantics/publishedVersio