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1.
Aging Ment Health ; 28(2): 377-383, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37789640

RESUMO

OBJECTIVES: Perceived control is a relevant variable for understanding middle and older adults' mental health. The Perceived Control Scale has two dimensions, Perceived Constraints on Personal Control and Perceived Mastery, and is a widely used instrument for assessing perceived control in adults. The aim of this study was to analyze the psychometric properties of the Spanish version of the Perceived Control Scale with data from two different studies. METHOD: In Study 1, 348 older adults between 60 and 92 years old were assessed through face-to-face assessments. In Study 2, 334 adults between 40 and 90 years completed an online survey. Perceived control, self-perceptions of aging, and anxiety and depressive symptomatology were assessed. An exploratory (Study 1) and confirmatory (Study 2) factor analysis of the Perceived Control Scale were performed, and reliability and its relationship with the other assessed variables were evaluated. RESULTS: Results from parallel, exploratory, and confirmatory factor analyses suggested that the Spanish version of the Perceived Control Scale has a bidimensional structure: Perceived Constraints on Personal Control and Perceived Mastery. Good internal consistency was found for the scale in both samples. The results revealed negative and significant associations with negative self-perceptions of aging, and anxiety and depressive symptomatology. CONCLUSION: The Spanish version of the Perceived Control Scale shows good psychometric properties which endorse its use with middle-aged and older adults assessed either face-to-face or through online surveys.


Assuntos
Transtornos de Ansiedade , Ansiedade , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Reprodutibilidade dos Testes , Ansiedade/diagnóstico , Inquéritos e Questionários , Envelhecimento , Psicometria/métodos , Análise Fatorial
2.
Vet Res ; 54(1): 111, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993922

RESUMO

Mastitis is an inflammatory disease in dairy cows, causing economic losses and reducing animal welfare. In order to contribute for the discovery of early and noninvasive indicators, our objective was to determine the effects of a lipopolysaccharide (LPS) challenge on the microRNA profile (miRNome) of milk fat, using microarray analyses in cows. Cows were fed a lactation diet at ad libitum intake (n = 6). At 27 ± 3 days in milk, cows were injected with 50 µg of LPS Escherichia coli in one healthy rear mammary quarter. Milk samples were collected just before LPS challenge (LPS-) and 6.5 h after LPS challenge (LPS +) from the same cows. Microarray analysis was performed using customized 8 × 60 K ruminant miRNA microarrays to compare LPS- to LPS + miRNome. In silico functional analyses were performed using OmicsNet and Mienturnet software. MiRNome comparison between LPS- and LPS + identified 37 differentially abundant miRNAs (q-value ≤ 0.05). The predicted target genes of the 37 differentially abundant miRNAs are mostly involved in cell life including apoptosis, cell cycle, proliferation and differentiation and in gene expression processes. MiRNome analyses suggest that miRNAs profile is related to the inflammation response of the mammary gland. In conclusion, we demonstrated that milk fat might be an easy and rapid source of miRNAs that are potential indicators of early mastitis in cows.


Assuntos
Doenças dos Bovinos , Mastite , MicroRNAs , Feminino , Bovinos , Animais , Leite , Lipopolissacarídeos/farmacologia , Lactação , Dieta/veterinária , Escherichia coli/genética , Mastite/veterinária , MicroRNAs/genética , MicroRNAs/metabolismo , Doenças dos Bovinos/metabolismo
3.
Environ Res ; 231(Pt 1): 116076, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37156357

RESUMO

Microalgae have remarkable potential for wastewater bioremediation since they can efficiently uptake nitrogen and phosphorus in a sustainable and environmentally friendly treatment system. However, wastewater composition greatly depends on its source and has a significant seasonal variability. This study aimed to evaluate the impact of different N:P molar ratios on the growth of Chlorella vulgaris and nutrient removal from synthetic wastewater. Furthermore, artificial neural network (ANN) threshold models, optimised by genetic algorithms (GAs), were used to model biomass productivity (BP) and nitrogen/phosphorus removal rates (RRN/RRP). The impact of various inputs culture variables on these parameters was evaluated. Microalgal growth was not nutrient limited since the average biomass productivities and specific growth rates were similar between the experiments. Nutrient removal efficiencies/rates reached 92.0 ± 0.6%/6.15 ± 0.01 mgN L-1 d-1 for nitrogen and 98.2 ± 0.2%/0.92 ± 0.03 mgP L-1 d-1 for phosphorus. Low nitrogen concentration limited phosphorus uptake for low N:P ratios (e.g., 2 and 3, yielding 36 ± 2 mgDW mgP-1 and 39 ± 3 mgDW mgP-1, respectively), while low phosphorus concentration limited nitrogen uptake with high ratios (e.g., 66 and 67, yielding 9.0 ± 0.4 mgDW mgN-1 and 8.8 ± 0.3 mgDW mgN-1, respectively). ANN models showed a high fitting performance, with coefficients of determination of 0.951, 0.800, and 0.793 for BP, RRN, and RRP, respectively. In summary, this study demonstrated that microalgae could successfully grow and adapt to N:P molar ratios between 2 and 67, but the nutrient uptake was impacted by these variations, especially for the lowest and highest N:P molar ratios. Furthermore, GA-ANN models demonstrated to be relevant tools for microalgal growth modelling and control. Their high fitting performance in characterising this biological system can contribute to reducing the experimental effort for culture monitoring (human resources and consumables), thus decreasing the costs of microalgae production.


Assuntos
Chlorella vulgaris , Microalgas , Humanos , Águas Residuárias , Fósforo , Nitrogênio/análise , Biomassa
4.
Aging Ment Health ; 27(7): 1307-1312, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36052973

RESUMO

OBJECTIVES: Behavioral and psychological symptoms of dementia (BPSD) are considered to cause ambivalent feelings in caregivers that may contribute to understanding their depressive symptoms. Transnational research is needed in order to increase our knowledge about the cross-cultural equivalence of theoretical models to understand caregivers' mental health. The aim of this study was to cross-culturally analyze the association between BPSD, ambivalent feelings and depressive symptoms in two samples of family caregivers of people with dementia from Spain and the UK. METHODS: Participants in this study were 432 caregivers who completed measures of BPSD, ambivalent feelings and depressive symptoms. The association between the assessed variables was tested through path-analysis, with differences between countries tested through multigroup analysis. RESULTS: The results suggest that the influence of BPSD on caregivers' depressive symptoms is indirect, through ambivalent feelings. The observed associations were equivalent between countries and explained a significant percentage of the variance of depressive symptoms. CONCLUSION: The findings of this study provide, for the first time, evidence of equivalent cross-cultural paths analyzing the role of ambivalent feelings for understanding caregivers' depressive symptoms. The practical implications of these results are discussed.

5.
J Environ Manage ; 337: 117678, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36948147

RESUMO

Water is the most valuable resource on the planet. However, massive anthropogenic activities generate threatening levels of biological, organic, and inorganic pollutants that are not efficiently removed in conventional wastewater treatment systems. High levels of conventional pollutants (carbon, nitrogen, and phosphorus), emerging chemical contaminants such as antibiotics, and pathogens (namely antibiotic-resistant ones and related genes) jeopardize ecosystems and human health. Conventional wastewater treatment systems entail several environmental issues: (i) high energy consumption; (ii) high CO2 emissions; and (iii) the use of chemicals or the generation of harmful by-products. Hence, the use of microalgal systems (entailing one or several microalgae species, and in consortium with bacteria) as environmental agents towards wastewater treatment has been seen as an environmentally friendly solution to remove conventional pollutants, antibiotics, coliforms and antibiotic resistance genes. In recent years, several authors have evaluated the use of microalgal systems for the treatment of different types of wastewater, such as agricultural, municipal, and industrial. Generally, microalgal systems can provide high removal efficiencies of: (i) conventional pollutants, up to 99%, 99%, and 90% of total nitrogen, total phosphorus, and/or organic carbon, respectively, through uptake mechanisms, and (ii) antibiotics frequently found in wastewaters, such as sulfamethoxazole, ciprofloxacin, trimethoprim and azithromycin at 86%, 65%, 42% and 93%, respectively, through the most desirable microalgal mechanism, biodegradation. Although pathogens removal by microalgal species is complex and very strain-specific, it is also possible to attain total coliform and Escherichia coli removal of 99.4% and 98.6%, respectively. However, microalgal systems' effectiveness strongly relies on biotic and abiotic conditions, thus the selection of operational conditions is critical. While the combination of selected species (microalgae and bacteria), ratios and inoculum concentration allow the efficient removal of conventional pollutants and generation of high amounts of biomass (that can be further converted into valuable products such as biofuels and biofertilisers), abiotic factors such as pH, hydraulic retention time, light intensity and CO2/O2 supply also have a crucial role in conventional pollutants and antibiotics removal, and wastewater disinfection. However, some rationale must be considered according to the purpose. While alkaline pH induces the hydrolysis of some antibiotics and the removal of faecal coliforms, it also decreases phosphates solubility and induces the formation of ammonium from ammonia. Also, while CO2 supply increases the removal of E. coli and Pseudomonas aeruginosa, as well as the microalgal growth (and thus the conventional pollutants uptake), it decreases Enterococcus faecalis removal. Therefore, this review aims to provide a critical review of recent studies towards the application of microalgal systems for the efficient removal of conventional pollutants, antibiotics, and pathogens; discussing the feasibility, highlighting the advantages and challenges of the implementation of such process, and presenting current case-studies of different applications of microalgal systems.


Assuntos
Poluentes Ambientais , Microalgas , Purificação da Água , Humanos , Águas Residuárias , Microalgas/metabolismo , Biomassa , Ecossistema , Dióxido de Carbono/metabolismo , Escherichia coli , Bactérias/metabolismo , Poluentes Ambientais/metabolismo , Fósforo/metabolismo , Nitrogênio/metabolismo , Antibacterianos/metabolismo , Carbono/metabolismo
6.
J Women Aging ; 35(4): 354-368, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35343403

RESUMO

The study assessed gender differences in the associations between familism dimensions, dysfunctional thoughts, and resource and outcome variables in 190 Spanish dementia family caregivers. A theoretical model was tested through path analysis, obtaining an excellent fit of the model to the data. Higher scores in the familial obligations dimension were associated with lower self-efficacy for self-care and obtaining respite and leisure frequency, and higher anxious and depressive feelings, in female caregivers only. Significant between-gender differences were obtained, suggesting that female caregivers holding strong familistic values are more vulnerable to the negative consequences of caregiving compared to male caregivers.


Assuntos
Cuidadores , Demência , Humanos , Masculino , Feminino , Fatores Sexuais , Adaptação Psicológica , Ansiedade , Estresse Psicológico
7.
Methods ; 186: 68-78, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32603824

RESUMO

The objective was to compare eight methods for estimation of dairy goat body composition, by calibrating against chemical composition (water, lipid, protein, mineral and energy) measured post-mortem. The methods tested on 20 Alpine goats were body condition score (BCS), 3-dimension imaging (3D) automatic assessment of BCS or whole body scan, ultrasound, computer tomography (CT), adipose cell diameter, deuterium oxide dilution space (D2OS) and bioelectrical impedance spectroscopy (BIS). Regressions were tested between predictive variates derived from the methods and empty body (EB) composition. The best equations for estimation of EB lipid mass included BW combined with i) perirenal adipose tissue mass and cell diameter (R2 = 0.95, residual standard deviation, rSD = 0.57 kg), ii) volume of fatty tissues measured by CT (R2 = 0.92, rSD = 0.76 kg), iii) D2OS (R2 = 0.91, rSD = 0.85 kg), and iv) resistance at infinite frequency from BIS (R2 = 0.87, rSD = 1.09 kg). The D2OS combined with BW provided the best equation for EB protein mass (R2 = 0.97, rSD = 0.17 kg), whereas BW alone provided a fair estimate (R2 = 0.92, rSD = 0.25 kg). Sternal BCS combined with BW provided good estimation of EB lipid and protein mass (R2 = 0.80 and 0.95, rSD = 1.27 and 0.22 kg, respectively). Compared to manual BCS, BCS by 3D slightly decreased the precision of the predictive equation for EB lipid (R2 = 0.74, rSD = 1.46 kg), and did not improve the estimation of EB protein compared with BW alone. Ultrasound measurements and whole body 3D imaging methods were not satisfactory estimators of body composition (R2 ≤ 0.40). Further developments in body composition techniques may contribute for high-throughput phenotyping of robustness.


Assuntos
Composição Corporal/fisiologia , Pesos e Medidas Corporais/métodos , Pesos e Medidas Corporais/veterinária , Cabras/fisiologia , Lactação/fisiologia , Tecido Adiposo/diagnóstico por imagem , Animais , Indústria de Laticínios/métodos , Feminino , Imageamento Tridimensional , Leite/metabolismo , Tomografia Computadorizada por Raios X , Ultrassonografia
8.
Artigo em Inglês | MEDLINE | ID: mdl-36209384

RESUMO

OBJECTIVE: To analyze the association between diverse medical conditions and depressive symptoms in different profiles of dementia caregivers based on sex and kinship (wives, husbands, daughters, and sons). METHODS: Individual interviews were conducted with 338 dementia family caregivers. Depressive symptoms were measured with the Spanish version of the Center for Epidemiologic Studies-Depression Scale. Medical conditions encompassed the following physical diseases: high cholesterol, osteoarthritis, hypertension, diabetes, cancer, and cardiovascular, brain, kidney, liver, and stomach diseases.Logistic regression analyses were carried out to identify determinants associated to thepresenceof depressive symptoms. RESULTS: High cholesterol was the most frequent disease among caregivers.Significant differences among groups were found in depressive symptoms: between wives (50.60%) and husbands (28.40%),(p = 0.033), and between daughters (57.00%) and husbands (p = 0.001). Half of the sonsreported thepresenceof depressive symptoms. In daughters, depressive symptomatology was significantly more likely whether they presented a worse reaction to disruptive behaviors, a poor assessment of global deterioration of care recipient, and less perceived health status. Furthermore, daughters were 1.94 times more likely to experience depressive symptoms if they presented medical conditions (p = 0.017). CONCLUSIONS: Daughter caregivers that have depressive and physical diseases may be an especially vulnerable subgroup of caregivers that may not be the ideal population to provide care. Access to high-quality, evidence-based therapies focused on improving caregivers' physical health could have a positiveeffecton thepresenceof depressive symptoms, particularly in the case of daughter caregivers.


Assuntos
Cuidadores , Demência , Colesterol , Depressão/diagnóstico , Humanos , Cônjuges
9.
Molecules ; 27(2)2022 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-35056728

RESUMO

This work aims to explore the gas permeation performance of two newly-designed ionic liquids, [C2mim][CF3BF3] and [C2mim][CF3SO2C(CN)2], in supported ionic liquid membranes (SILM) configuration, as another effort to provide an overall insight on the gas permeation performance of functionalized-ionic liquids with the [C2mim]+ cation. [C2mim][CF3BF3] and [C2mim][CF3SO2C(CN)2] single gas separation performance towards CO2, N2, and CH4 at T = 293 K and T = 308 K were measured using the time-lag method. Assessing the CO2 permeation results, [C2mim][CF3BF3] showed an undermined value of 710 Barrer at 293.15 K and 1 bar of feed pressure when compared to [C2mim][BF4], whereas for the [C2mim][CF3SO2C(CN)2] IL an unexpected CO2 permeability of 1095 Barrer was attained at the same experimental conditions, overcoming the results for the remaining ILs used for comparison. The prepared membranes exhibited diverse permselectivities, varying from 16.9 to 22.2 for CO2/CH4 and 37.0 to 44.4 for CO2/N2 gas pairs. The thermophysical properties of the [C2mim][CF3BF3] and [C2mim][CF3SO2C(CN)2] ILs were also determined in the range of T = 293.15 K up to T = 353.15 K at atmospheric pressure and compared with those for other ILs with the same cation and anion's with similar chemical moieties.

10.
J Vet Med Educ ; 49(1): 39-44, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34003735

RESUMO

Fine needle aspiration (FNA) is widely used by veterinary practitioners, being taught mostly by observation. Simulators are known to enhance students' learning of practice skills, but to our knowledge, FNA simulators have never been assessed in veterinary medicine. Fifty-one undergraduate students with no prior experience in cytology were randomly assigned to two groups that practiced on either a box simulator (with artificial nodules) or a fruit (banana). An in-class flip was followed, in which students first observed a FNA video tutorial and then used their assigned simulator for 15 minutes maximum. Students then attempted a FNA on an animal model and were evaluated through an objective structured clinical examination (OSCE). Learning outcomes of each model was compared through questionnaires, OSCE pass rates, and quality of produced smears. After observing the video, no student reported being able to conduct a FNA on a live animal, whereas most assured that they would be able to do so after using a simulator. Students practiced more on the box model (14.8 ± 0.8 min) than on the fruit (8.5 ± 2.2 min). At evaluation, students who had practiced on the box had more puncturing accuracy than those who had practiced on the fruit. Still, no differences in OSCE pass rates existed. Simulation models thus were effective for learning FNA, but the box simulator seemed to be more successful than the fruit in terms of deliberate practice. This appears to have a positive effect on students' puncturing accuracy, which has clinical relevance.


Assuntos
Biópsia por Agulha Fina , Educação em Veterinária , Treinamento por Simulação , Animais , Humanos , Biópsia por Agulha Fina/veterinária , Competência Clínica , Educação em Veterinária/métodos , Aprendizagem , Estudantes
11.
Clin Gerontol ; 45(1): 71-85, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34096470

RESUMO

OBJECTIVES: To analyze caregivers' perceived impact of the pandemic in their mental health and the well-being of the care-recipients. METHODS: Caregivers (N = 88) were asked if they had COVID-19 and about their perceptions of change of care-recipients' health conditions as well as whether their own mental health, conflicts with care-recipients and other relatives, thoughts of giving up caregiving, and feelings of coping well with the situation. RESULTS: A large percentage of caregivers perceived a worsening of care-recipients' symptoms and of their own negative emotions, an increase in the number of conflicts and thoughts of needing to give up caregiving. Having had COVID-19 and reporting higher levels of distress as well as giving up caregiving were related to perceived worsening in care-recipients well-being. Perceived increases were mainly reported by younger caregivers, those who perceived to have not coped well, and those reporting an increase in conflicts. Some caregivers perceived an increase in positive emotions. CONCLUSIONS: The pandemic has a negative impact on caregivers' perceptions about the course of their own emotions and care-recipients' well-being. CLINICAL IMPLICATIONS: Interventions are needed to train caregivers in strategies to cope with the sources of stress caused by the pandemic and to promote social support.


Assuntos
COVID-19 , Demência , Adaptação Psicológica , Cuidadores , Humanos , SARS-CoV-2
12.
J Struct Biol ; 213(2): 107715, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33705979

RESUMO

The 106-residue protein Q4DY78 (UniProt accession number) from Trypanosoma cruzi is highly conserved in the related kinetoplastid pathogens Trypanosoma brucei and Leishmania major. Given the essentiality of its orthologue in T. brucei, the high sequence conservation with other trypanosomatid proteins, and the low sequence similarity with mammalian proteins, Q4DY78 is an attractive protein for structural characterization. Here, we solved the structure of Q4DY78 by solution NMR and evaluated its backbone dynamics. Q4DY78 is composed of five α -helices and a small, two-stranded antiparallel ß-sheet. The backbone RMSD is 0.22 ± 0.05 Å for the representative ensemble of the 20 lowest-energy structures. Q4DY78 is overall rigid, except for N-terminal residues (V8 to I10), residues at loop 4 (K57 to G65) and residues at the C-terminus (F89 to F112). Q4DY78 has a short motif FPCAP that could potentially mediate interactions with the host cytoskeleton via interaction with EVH1 (Drosophila Enabled (Ena)/Vasodilator-stimulated phosphoprotein (VASP) homology 1) domains. Albeit Q4DY78 lacks calcium-binding motifs, its fold resembles that of eukaryotic calcium-binding proteins such as calcitracin, calmodulin, and polcacin Bet V4. We characterized this novel protein with a calcium binding fold without the capacity to bind calcium.


Assuntos
Proteínas de Protozoários/química , Trypanosoma cruzi/química , Sequência de Aminoácidos , Sítios de Ligação , Cálcio/metabolismo , Moléculas de Adesão Celular/química , Dicroísmo Circular , Sequência Conservada , Motivos EF Hand , Proteínas dos Microfilamentos/química , Modelos Moleculares , Isótopos de Nitrogênio , Ressonância Magnética Nuclear Biomolecular , Fosfoproteínas/química , Conformação Proteica em alfa-Hélice , Estrutura Secundária de Proteína , Proteínas de Protozoários/metabolismo
13.
Behav Sleep Med ; 19(5): 640-651, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33084405

RESUMO

OBJECTIVES: Behavioral problems in people with dementia are a source of depression and anxiety for caregivers, who experience high levels of sleep problems. The present study aims to explore the role of sleep problems on the relationship between behavioral problems associated with dementias - considering its different dimensions - and family caregivers' depressive and anxious symptoms. METHOD: 264 family caregivers participated in the study. Through face-to-face interviews, sociodemographic and health variables, caregivers' depressive and anxious symptoms were measured, as well as their sleep problems. Data related to people with dementia symptoms and their level of independence in daily life activities were also collected. Data analysis consisted of simple mediational models using the PROCESS method for SPSS. RESULTS: the test for the indirect effect of disruptive behaviors on depression through sleep problems was statistically significant, as it was for disruptive behaviors on anxiety through sleep problems. The effect of sleep problems in the association between depressive and memory problems in the person with dementia, and caregivers' depression and anxiety were not statistically significant. CONCLUSIONS: Sleep problems are significantly and positively associated with care-recipients' disruptive behaviors, but not with depressive and memory problems. The indirect effect of disruptive behaviors on caregivers' mood through sleep problems suggests that disruptive behaviors seem to play an important role for understanding caregivers' sleep problems.


Assuntos
Ansiedade/complicações , Cuidadores/psicologia , Demência/psicologia , Depressão/complicações , Transtornos do Sono-Vigília/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
J Struct Biol ; 211(2): 107536, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32473201

RESUMO

Complete genome sequencing of the kinetoplastid protozoans Trypanosoma cruzi, Trypanosoma brucei and Leishmania major (Tritryp), published in 2005, opened up new perspectives for drug development targeting Chagas disease, African sleeping sickness and Leishmaniasis, neglected diseases affecting millions of most economically disadvantaged people. Still, half of the Tritryp genes code for proteins of unknown function. Moreover, almost 50% of conserved eukaryotic protein domains are missing in the Tritryp genomes. This suggests that functional and structural characterization of proteins of unknown function could reveal novel protein folds used by the trypanosomes for common cellular processes. Furthermore, proteins without homologous counterparts in humans may provide potential targets for therapeutic intervention. Here we describe the crystal structure of the T. cruzi protein Q4D6Q6, a conserved and kinetoplastid-specific protein essential for cell viability. Q4D6Q6 is a representative of a family of 20 orthologs, all annotated as proteins of unknown function. Q4D6Q6 monomers adopt a ßßαßßαßß topology and form a propeller-like tetramer. Oligomerization was verified in solution using NMR, SAXS, analytical ultra-centrifugation and gel filtration chromatography. A rigorous search for similar structures using the DALI server revealed similarities with propeller-like structures of several different functions. Although a Q4D6Q6 function could not be inferred from such structural comparisons, the presence of an oxidized cysteine at position 69, part of a cluster with phosphorylated serines and hydrophobic residues, identifies a highly reactive site and suggests a role of this cysteine as a nucleophile in a post-translational modification reaction.


Assuntos
Proteínas de Protozoários/ultraestrutura , Trypanosoma cruzi/ultraestrutura , Animais , Humanos , Leishmania major/ultraestrutura , Modelos Moleculares , Proteínas de Protozoários/genética , Espalhamento a Baixo Ângulo , Trypanosoma brucei brucei/ultraestrutura , Trypanosoma cruzi/genética , Difração de Raios X
15.
J Struct Biol ; 206(3): 280-294, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30930219

RESUMO

Subtilisin-like proteases play crucial roles in host-pathogen interactions. Thus, protease inhibitors constitute important tools in the regulation of this interaction. CmPI-II is a Kazal proteinase inhibitor isolated from Cenchritis muricatus that inhibits subtilisin A, trypsin and elastases. Based on sequence analysis it defines a new group of non-classical Kazal inhibitors. Lacking solved 3D structures from this group prevents the straightforward structural comparison with other Kazal inhibitors. The 3D structure of CmPI-II, solved in this work using NMR techniques, shows the typical fold of Kazal inhibitors, but has significant differences in its N-terminal moiety, the disposition of the CysI-CysV disulfide bond and the reactive site loop (RSL) conformation. The high flexibility of its N-terminal region, the RSL, and the α-helix observed in NMR experiments and molecular dynamics simulations, suggest a coupled motion of these regions that could explain CmPI-II broad specificity. The 3D structure of the CmPI-II/subtilisin A complex, obtained by modeling, allows understanding of the energetic basis of the subtilisin A inhibition. The residues at the P2 and P2' positions of the inhibitor RSL were predicted to be major contributors to the binding free energy of the complex, rather than those at the P1 position. Site directed mutagenesis experiments confirmed the Trp14 (P2') contribution to CmPI-II/subtilisin A complex formation. Overall, this work provides the structural determinants for the subtilisin A inhibition by CmPI-II and allows the designing of more specific and potent molecules. In addition, the 3D structure obtained supports the existence of a new group in non-classical Kazal inhibitors.


Assuntos
Motivos Kazal/genética , Conformação Molecular , Complexos Multiproteicos/ultraestrutura , Inibidores da Tripsina/química , Sequência de Aminoácidos/genética , Animais , Sítios de Ligação/genética , Inibidores Enzimáticos/química , Gastrópodes/química , Interações Hospedeiro-Patógeno/genética , Motivos Kazal/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Simulação de Dinâmica Molecular , Complexos Multiproteicos/química , Complexos Multiproteicos/genética , Elastase Pancreática/antagonistas & inibidores , Elastase Pancreática/ultraestrutura , Ligação Proteica/genética , Inibidores de Serina Proteinase/química , Subtilisinas/antagonistas & inibidores , Subtilisinas/ultraestrutura , Tripsina/química , Tripsina/ultraestrutura
16.
Int J Mol Sci ; 20(5)2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30845783

RESUMO

: The objective is to study the effects of nutrient restrictions, which induce a metabolic imbalance on the inflammatory response of the mammary gland in early lactation cows. The aim is to decipher the molecular mechanisms involved, by comparing a control, with a restriction group, a transcriptome and proteome, after an intra-mammary lipopolysaccharide challenge. Multi-parous cows were either allowed ad libitum intake of a lactation diet (n = 8), or a ration containing low nutrient density (n = 8; 48% barley straw and dry matter basis) for four days starting at 24 ± 3 days in milk. Three days after the initiation of their treatments, one healthy rear mammary quarter of 12 lactating cows was challenged with 50 µg of lipopolysaccharide (LPS). Transcriptomic and proteomic analyses were performed on mammary biopsies obtained 24 h after the LPS challenge, using bovine 44K microarrays, and nano-LC-MS/MS, respectively. Restriction-induced deficits in energy, led to a marked negative energy balance (41 versus 97 ± 15% of Net Energy for Lactation (NEL) requirements) and metabolic imbalance. A microarray analyses identified 25 differentially expressed genes in response to restriction, suggesting that restriction had modified mammary metabolism, specifically ß-oxidation process. Proteomic analyses identified 53 differentially expressed proteins, which suggests that the modification of protein synthesis from mRNA splicing to folding. Under-nutrition influenced mammary gland expression of the genes involved in metabolism, thereby increasing ß-oxidation and altering protein synthesis, which may affect the response to inflammation.


Assuntos
Restrição Calórica/efeitos adversos , Perfilação da Expressão Gênica/métodos , Lipopolissacarídeos/efeitos adversos , Glândulas Mamárias Animais/metabolismo , Proteômica/métodos , Animais , Bovinos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Lactação , Glândulas Mamárias Animais/efeitos dos fármacos , Nutrigenômica , Necessidades Nutricionais , Análise de Sequência com Séries de Oligonucleotídeos/veterinária
17.
Environ Model Softw ; 106: 13-21, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30078988

RESUMO

Background pollution represents the lowest levels of ambient air pollution to which the population is chronically exposed, but few studies have focused on thoroughly characterizing this regime. This study uses clustering statistical techniques as a modelling approach to characterize this pollution regime while deriving reliable information to be used as estimates of exposure in epidemiological studies. The background levels of four key pollutants in five urban areas of Andalusia (Spain) were characterized over an 11-year period (2005-2015) using four widely-known clustering methods. For each pollutant data set, the first (lowest) cluster representative of the background regime was studied using finite mixture models, agglomerative hierarchical clustering, hidden Markov models (hmm) and k-means. Clustering method hmm outperforms the rest of the techniques used, providing important estimates of exposures related to background pollution as its mean, acuteness and time incidence values in the ambient air for all the air pollutants and sites studied.

18.
J Vet Med Educ ; 49(1): 138-143, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35120303

RESUMO

A punção de agulha fina (PAF) é amplamente utilizada por veterinários, sendo ensinada maioritariamente por observação. Atualmente, considera-se que a utilização de simuladores melhora a aprendizagem de procedimentos práticos. No entanto, simuladores de PAF ainda não foram avaliados em Medicina Veterinária. Cinquenta e um estudantes de Veterinária sem experiência prévia em Citologia foram distribuídos aleatoriamente em dois grupos que usaram um simulador (caixa com nódulos artificiais) e uma peça de fruta (banana). Foi utilizado um desenho de aula invertida com estações: primeiramente, os estudantes observaram um vídeo tutorial sobre a PAF, utilizando em seguida o simulador ou a peça de fruta durante um máximo de 15 minutos. Depois, os estudantes efetuaram o procedimento num modelo animal realista, realizando-se uma avaliação clínica objetiva estruturada (ACOE). A aprendizagem através dos modelos foi comparada por meio de questionários, taxa de aprovação em ACOE e qualidade dos esfregaços obtidos. Após observar o vídeo tutorial, nenhum estudante manifestou ser capaz de fazer a PAF num animal vivo. Por oposição, a maioria revelou ser capaz após a simulação. Os estudantes praticaram mais tempo na caixa (14,8 ± 0,8 min) do que na peça de fruta (8,5 ± 2,2 min). Na avaliação, os primeiros tinham maior precisão na PAF. Ainda assim, não existiram diferenças na taxa de aprovação em ACOE. Portanto, os dois modelos são eficazes para a aprendizagem da PAF, mas a caixa tem vantagens quanto à repetição autónoma da prática. Essa repetição parece ter efeitos positivos na precisão da PAF, o que tem relevância do ponto de vista clínico.

19.
Protein Expr Purif ; 126: 127-136, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27353494

RESUMO

Cenchritis muricatus protease inhibitor II (CmPI-II) is a tight-binding serine protease inhibitor of the Kazal family with an atypical broad specificity, being active against several proteases such as bovine pancreatic trypsin, human neutrophil elastase and subtilisin A. CmPI-II 3D structures are necessary for understanding the molecular basis of its activity. In the present work, we describe an efficient and straightforward recombinant expression strategy, as well as a cost-effective procedure for isotope labeling for NMR structure determination purposes. The vector pCM101 containing the CmPI-II gene, under the control of Pichia pastoris AOX1 promoter was constructed. Methylotrophic Pichia pastoris strain KM71H was then transformed with the plasmid and the recombinant protein (rCmPI-II) was expressed in benchtop fermenter in unlabeled or (15)N-labeled forms using ammonium chloride ((15)N, 99%) as the sole nitrogen source. Protein purification was accomplished by sequential cation exchange chromatography in STREAMLINE DirectHST, anion exchange chromatography on Hitrap Q-Sepharose FF and gel filtration on Superdex 75 10/30, yielding high quantities of pure rCmPI-II and (15)N rCmPI-II. Recombinant proteins displayed similar functional features as compared to the natural inhibitor and NMR spectra indicated folded and homogeneously labeled samples, suitable for further studies of structure and protease-inhibitor interactions.


Assuntos
Gastrópodes/genética , Pichia/metabolismo , Inibidores de Serina Proteinase , Animais , Bovinos , Gastrópodes/metabolismo , Humanos , Ressonância Magnética Nuclear Biomolecular , Pichia/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Inibidores de Serina Proteinase/biossíntese , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/genética , Inibidores de Serina Proteinase/isolamento & purificação
20.
Int J Mol Sci ; 17(11)2016 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-27869676

RESUMO

Landfill leachates result from the degradation of solid residues in sanitary landfills, thus presenting a high variability in terms of composition. Normally, these effluents are characterized by high ammoniacal-nitrogen (N-NH4⁺) concentrations, high chemical oxygen demands and low phosphorus concentrations. The development of effective treatment strategies becomes difficult, posing a serious problem to the environment. Phycoremediation appears to be a suitable alternative for the treatment of landfill leachates. In this study, the potential of Chlorella vulgaris for biomass production and nutrients (mainly nitrogen and phosphorus) removal from different compositions of a landfill leachate was evaluated. Since microalgae also require phosphorus for their growth, different loads of this nutrient were evaluated, giving the following N:P ratios: 12:1, 23:1 and 35:1. The results have shown that C. vulgaris was able to grow in the different leachate compositions assessed. However, microalgal growth was higher in the cultures presenting the lowest N-NH4⁺ concentration. In terms of nutrients uptake, an effective removal of N-NH4⁺ and phosphorus was observed in all the experiments, especially in those supplied with phosphorus. Nevertheless, N-NO3- removal was considered almost negligible. These promising results constitute important findings in the development of a bioremediation technology for the treatment of landfill leachates.


Assuntos
Amônia/isolamento & purificação , Chlorella vulgaris/metabolismo , Microalgas/metabolismo , Nitratos/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Biodegradação Ambiental , Chlorella vulgaris/crescimento & desenvolvimento , Microalgas/crescimento & desenvolvimento , Instalações de Eliminação de Resíduos
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