Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 269
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
J Intellect Disabil Res ; 68(1): 84-93, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37698385

RESUMO

BACKGROUND: Motor control issues are common for people with intellectual disabilities (PWID), resulting in difficulties with basic activities of daily living, including eating. Mastication, which is crucial for digestion and overall health, is poorly understood in this population. PWID shows frailty similar to older people, highlighting the importance of comparing masticatory motor control with older adults. This study compared the neuromuscular control of the masticatory muscles in middle-aged, PWID and older adults. METHODS: A cross-sectional analytical design was used. During the mastication task of a carrot piece (2 cm in diameter and weighing 0.5 g), surface electromyography was used to record muscle activity patterns from the right and left masseter and temporalis muscles. Principal component analysis (PCA) was used to assess neuromuscular control. A z-score normalisation of the first component's variance from PCA to identify those individuals with altered neuromuscular control. A mixed ANOVA was performed to assess the interaction between principal components, groups and body composition. RESULTS: Thirty PWIDs (aged 35-55 years), middle-aged adults and 32 older adults were recruited. PWID and older adults showed decreased neuromuscular control of the masticatory muscles compared to middle-aged control adults (P < 0.05). PWID had the highest proportion of individuals with altered neuromuscular control of the masticatory muscle (53%) compared to older adults (19%) and middle-aged adults (0%) (P < 0.05). CONCLUSIONS: Our results indicate that PWID and older adults have reduced neuromuscular control compared to middle-aged adults. Notably, a significant proportion of the PWID showed altered masticatory muscle control compared to older adults. Further research is needed to explore the potential benefits of masticatory muscle training for PWID.


Assuntos
Deficiência Intelectual , Abuso de Substâncias por Via Intravenosa , Pessoa de Meia-Idade , Humanos , Idoso , Atividades Cotidianas , Estudos Transversais , Músculos da Mastigação/fisiologia
2.
J Intellect Disabil Res ; 67(7): 630-639, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37042218

RESUMO

BACKGROUND: Alterations in oral health have a negative impact on the quality of life of persons with intellectual disabilities (PwIDs). Chewing is a process that influences and determines optimal oral health. However, little is known about how intellectual disability (ID) affects masticatory performance. This study aimed to analyse the differences in masticatory performance between young adults with IDs, young adults without IDs and older adults without IDs. METHODS: A cross-sectional analytical design was used. The masticatory performance was evaluated with a chewing gum validated instrument. In addition, the labial and tongue strength was assessed with the Iowa Oral Performance Instrument. We compared the masticatory performance between groups using one-way analysis of covariance. Body mass index, muscle mass, missing teeth, lip strength and tongue strength were included as separate covariates. A multivariate regression analysis was performed to identify which independent variables could explain masticatory performance in each group. RESULTS: Thirty-two PwIDs, 31 young adults without IDs and 32 older adults without IDs were recruited. PwIDs showed poorer masticatory performance compared with older adults (mean difference: -3.06, 95% confidence interval: -3.87 to -2.26) and healthy controls (mean difference: -2.38, 95% confidence interval: -3.19 to -1.57). The analysis of covariance showed significant difference between groups in the masticatory performance (F = 47.35, P < 0.001, ηp 2  = 0.507). Missing teeth (P < 0.001), right lip strength (P = 0.025) and tongue strength (P = 0.007) as covariables showed a significant interaction with the model. In the PwID group, lip strength and lack of teeth explained 58% of the variance in masticatory performance (R2  = 0.580, standard error = 1.12, P < 0.001). CONCLUSIONS: Persons with intellectual disabilities have a poorer masticatory performance than adults without IDs. Our findings indicate that the primary determinants of optimal masticatory function in PwIDs are the strength of the lip seal and the number of missing teeth.


Assuntos
Deficiência Intelectual , Humanos , Adulto Jovem , Idoso , Estudos Transversais , Lábio , Qualidade de Vida , Língua/fisiologia
3.
Occup Med (Lond) ; 73(3): 128-132, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-36719103

RESUMO

BACKGROUND: Antibody (Ab) tests for SARS-CoV-2 virus allows for the estimation of incidence, level of exposure and duration of immunity acquired by a previous infection. In health workers, the hospital setting might convey a greater risk of infection. AIMS: To describe the frequency of immunoglobulin G (IgG) Abs (IgG-Abs) to the SARS-CoV-2 virus among workers at a third-level university hospital in Colombia. METHODS: In this cross-sectional study, we included medical and non-medical personnel with at least one real-time polymerase chain reaction (RT-PCR)/antigen test between March 2020 and March 2021. In April 2021, an IgG-Ab test against SARS-CoV-2 was conducted for all participants and replicated 2 weeks later in a random sample (10%). The frequency of IgG-Abs is presented based on status (positive/negative) and time elapsed since RT-PCR/antigen test (<3 months, 3-6 months, >6 months). RESULTS: We included 1021 workers (80% women, median age 34 years (interquartile range 28-42), 73% medical personnel, 23% with previous positive RT-PCR/antigen). The overall seroprevalence was 35% (95% CI 31.6-37.4, 35% in medical and 33% in non-medical personnel). For those with a previous positive RT-PCR/antigen test, the seroprevalence was 90% (<3 months), 82% (3-6 months) and 48% (>6 months). In participants with a previous negative RT-PCR/antigen test, the seroprevalence was 17% (<3 months), 21% (3-6 months) and 29% (>6 months). CONCLUSIONS: High IgG-Ab positivity was found in hospital personnel, regardless of work activities. The prevalence of detectable Abs differed by previous RT-PCR/antigen status and time elapsed since the diagnostic test.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Feminino , Adulto , Masculino , COVID-19/epidemiologia , Colômbia/epidemiologia , Estudos Soroepidemiológicos , Estudos Transversais , Imunoglobulina G , Pessoal de Saúde , Recursos Humanos em Hospital , Hospitais
4.
Occup Med (Lond) ; 73(8): 464-469, 2023 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-37665779

RESUMO

BACKGROUND: Despite extensive investigation of ergonomic risk factors for spinal pain in healthcare workers, limited knowledge of psychological risk factors exists. AIMS: To assess the prospective association of mental health and vitality with development of spinal pain in healthcare workers. METHODS: A prospective cohort study was carried out involving 1950 healthcare workers from 19 hospitals in Denmark. Assessments were done at baseline and at 1-year follow-up. Mental health and vitality were measured using the Short Form-36 Health Survey, while spinal pain intensity was measured using a 0-10 scale in the low-back, upper-back and neck, respectively. Cumulative logistic regressions adjusted for several confounding factors were applied, reporting risk estimates as odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Using good mental health as reference, moderate (but not poor) mental health at baseline was associated with increased pain intensity in the low-back (OR: 1.41 [95% CI: 1.21-1.77]), upper-back (OR: 1.63 [95% CI: 1.31-2.02]) and neck (OR: 1.31 [95% CI: 1.07-1.61]) at 1-year follow-up. Likewise, using high vitality as reference, both moderate and low vitality at baseline were associated with increased pain intensity in the low-back (OR: 1.54 [95% CI: 1.22-1.94] and OR: 2.34 [95% CI: 1.75-3.12], respectively), upper-back (OR: 1.72 [95% CI: 1.34-2.23] and OR: 2.46 [95% CI: 1.86-3.25], respectively) and neck (OR: 1.66 [95% CI: 1.34-2.06] and OR: 2.06 [95% CI: 1.61-2.63], respectively) at 1-year follow-up. CONCLUSIONS: Compared to healthcare workers with good mental health and high vitality, those with moderate mental health and low/moderate vitality, respectively, were more likely to increase spinal pain intensity at 1-year follow-up. These components should also be considered in the prevention of spinal pain in healthcare workers.


Assuntos
Dor Lombar , Saúde Mental , Humanos , Estudos Prospectivos , Cervicalgia/epidemiologia , Cervicalgia/etiologia , Pessoal de Saúde
5.
Lett Appl Microbiol ; 62(2): 177-84, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26612600

RESUMO

UNLABELLED: Antibiotic-resistant Salmonella strains were isolated from saladette and red round type tomatoes, and an analysis done of the antibacterial activity of roselle calyx extracts against any of the identified strains. One hundred saladette tomato samples and 100 red round tomato samples were collected from public markets. Each sample consisted of four whole tomatoes. Salmonella was isolated from the samples by conventional culture procedure. Susceptibility to 16 antibiotics was tested for the isolated Salmonella strains by standard test. The antibacterial effect of four roselle calyx extracts (water, methanol, acetone and ethyl acetate), sodium hypochlorite and acetic acid against antibiotic-resistant Salmonella isolates was evaluated on contaminated tomatoes. Twenty-four Salmonella strains were isolated from 12% of each tomato type. Identified Salmonella serotypes were Typhimurium and Typhi. All isolated strains exhibited resistance to at least three antibiotics and some to as many as 12. Over contaminated tomatoes, the roselle calyx extracts produced a greater reduction (2-2·6 log) in antibiotic-resistant Salmonella strain concentration than sodium hypochlorite and acetic acid. SIGNIFICANCE AND IMPACT OF THE STUDY: The presence of multidrug-resistant Salmonella in vegetables is a significant public health concern. Multidrug-resistant Salmonella strains were isolated from raw tomatoes purchased in public markets in Mexico and challenged with roselle Hibiscus sabdariffa calyx extracts, sodium hypochlorite and acetic acid. On tomatoes, the extracts caused a greater reduction in the concentration of antibiotic-resistant Salmonella strains than sodium hypochlorite and acetic acid. Roselle calyx extracts are a potentially useful addition to disinfection procedures of raw tomatoes in the field, processing plants, restaurants and homes.


Assuntos
Ácido Acético/farmacologia , Desinfetantes/farmacologia , Hibiscus/metabolismo , Extratos Vegetais/farmacologia , Salmonella typhi/efeitos dos fármacos , Salmonella typhimurium/efeitos dos fármacos , Hipoclorito de Sódio/farmacologia , Solanum lycopersicum/microbiologia , Antibacterianos/farmacologia , Desinfecção/métodos , Farmacorresistência Bacteriana Múltipla , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , México , Testes de Sensibilidade Microbiana , Salmonella typhi/isolamento & purificação , Salmonella typhimurium/isolamento & purificação
6.
J Environ Manage ; 184(Pt 3): 609-616, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27784580

RESUMO

A great investment has been done in the last decades in the development of numerical and qualitative assessment methods to classify the ecological quality of water bodies. Yet, in spite of all attempts to avoid subjectivity, expert judgment is still used at numerous steps of the ecological classification and is considered by some authors as indispensible for management purposes. Thus, the aim of this study is to test the hypothesis that expert judgment, when done by the adequate experts (limnologists/river ecologist) with experience in the study area (i.e., natural conditions and expected communities), could be as good as quantitative indices and measures (i.e., result in the same classification), but quicker and with lower cost. For that we compared the classifications (on 13 aspects of rivers ecosystems) attributed by two experts to 20 sites (10 each) located in their study areas, with the classifications of ecological quality based on biological indices (for invertebrates and diatoms), hydromorphology and water chemistry, calculated by an independent team. Our results show that assessments made by experts and those calculated through indices (biological quality and hydromorphology) are globally very similar (RELATE test; Rho = 0.442; p < 0.001, 999 permutations). Most differences were of one class and experts tended to attribute a better condition than indices to the best quality sites but a worse condition to the worse quality sites. A Principal Components Analysis revealed that sites to which experts attributed a moderate quality had higher nitrate concentration and pH but were well oxygenated. The sites classified as poor and bad where those with stronger modifications in their habitats (given by the higher values of HMS). The difference between experts and indices is small but still represents 15% of sites, and includes both situations: the experts or the indices lead to the need of measures (i.e., classifications below class Good). Experts' evaluations on hydromorphological conditions of the channel and margins are also significantly correlated with the quality assessments made by the field team that has no experience in the study area (Rh0 = 0.518; p = 0.001; 999 permutation), indicating geographic independence in the expert judgment. We concluded that expert judgment could be used in the determination of streams and rivers ecological quality, saving money and time and helping to redirect monitoring funds to actual implementation of restoration measures. Yet, classification' scoring methods may still be useful for a better targeting of restoration measures.


Assuntos
Ecologia/métodos , Rios , Animais , Diatomáceas , Ecossistema , Monitoramento Ambiental , Humanos , Invertebrados , Julgamento
7.
Artif Organs ; 39(10): 868-75, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26471138

RESUMO

Neuromuscular electrical stimulation (NMES) is an established method for functional restoration of muscle function, rehabilitation, and diagnostics. In this work, NMES was applied with surface electrodes placed on the anterior thigh to identify the main differences between current-controlled (CC) and voltage-controlled (VC) modes. Measurements of the evoked knee extension force and the myoelectric signal of quadriceps and hamstrings were taken during stimulation with different amplitudes, pulse widths, and stimulation techniques. The stimulation pulses were rectangular and symmetric biphasic for both stimulation modes. The electrode-tissue impedance influences the differences between CC and VC stimulation. The main difference is that for CC stimulation, variation of pulse width and amplitude influences the amount of nerve depolarization, whereas VC stimulation is only dependent on amplitude variations for pulse widths longer than 150 µs. An important remark is that these findings are strongly dependent on the characteristics of the electrode-skin interface. In our case, we used large stimulation electrodes placed on the anterior thigh, which cause higher capacitive effects. The controllability, voltage compliance, and charge characteristics of each stimulation technique should be considered during the stimulators design. For applications that require the activation of a large amount of nerve fibers, VC is a more suitable option. In contrast, if the application requires a high controllability, then CC should be chosen prior to VC.


Assuntos
Músculo Esquelético/fisiologia , Estimulação Elétrica Nervosa Transcutânea/métodos , Adulto , Eletrodos , Feminino , Humanos , Masculino , Adulto Jovem
8.
Genet Mol Res ; 14(3): 10165-71, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26345953

RESUMO

Bite mark evidence has been repeatedly found in criminal cases. Physical comparison of a bite mark to the teeth of available suspects may not always be possible. Experimental studies have shown that the analysis of DNA present in the saliva recovered from bite marks might help in the identification of individuals. However, the application of this approach to an actual criminal case has been reported only once before in forensic literature. Therefore, there is very limited scientific and technical information available on this subject. The current study focuses on a woman found dead in her home; the autopsy ruled the death to be a result of manual strangulation. A bite mark was found on each breast. The single swab technique was used to collect evidence from these bite marks, and an organic extraction method was employed for DNA isolation. Short tandem repeat (STR) sequence typing was performed using a commercially available kit, and the result was compared to the STR profile of a suspect. A full single-source STR profile was obtained from both bite marks, which matched the STR profile of the suspect. To the best of our knowledge, this is the second report on the analysis of DNA isolated from bite marks on the victim used to identify the crime perpetrator. Our results indicated that, contrary to most theoretical indications, a single swab technique for evidence collection and an organic method for DNA isolation could be very useful in solving this class of criminal cases.


Assuntos
Mordeduras e Picadas/diagnóstico , DNA/isolamento & purificação , Biologia Molecular/métodos , Saliva/metabolismo , Feminino , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade
9.
Neurobiol Dis ; 64: 36-47, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24370700

RESUMO

The most appropriate time for the initiation of dopaminergic symptomatic therapy in Parkinson's disease remains debatable. It has been suggested that early correction of basal ganglia pathophysiological abnormalities may have long-term beneficial effects. To test this hypothesis, we investigated the early and delayed actions of L-dopa and pramipexole, using a delayed-start protocol of treatment. The effects of early and delayed administration of these drugs on motor response, development of dyskinesias, neurogenesis and molecular markers in basal ganglia were studied in rats with a unilateral and partial 6-hydroxydopamine-induced nigrostriatal lesion. Ten days after lesioning, rats received treatment with: a) L-dopa methyl ester (25mg/kg with 6.25mg/kg of benserazide, i.p., twice a day); b) pramipexole (0.5mg/kg, sc, twice a day) or c) saline for 4weeks. Four weeks after treatment initiation, rats from the saline group were distributed in three groups that then received the following treatments: d) L-dopa, e) pramipexole or f) saline, for 4weeks more. Three animals in each treatment arm received 5-bromo-2-deoxyuridine injections (200mg/kg) 3days before starting treatment. When compared with delayed-start L-dopa, early-start L-dopa treatment induced a lower rotational response (p<0.01), an improvement in limb akinesia (p<0.05), a lower level of dyskinesia (p<0.01) and a normalization of lesion-induced molecular changes in basal ganglia. When compared with delayed-start pramipexole, early-start pramipexole induced a higher rotational response (p<0.01), but did not improve limb akinesia, induce dyskinesia nor normalize lesion-induced molecular changes. Neither significant modifications of striatal dopamine D1-D3 receptor heteromerization nor subventricular zone neurogenesis was found after any L-dopa or pramipexole treatments. Our data support a possible restoration of basal ganglia physiological mechanisms by early-start L-dopa therapy.


Assuntos
Antiparkinsonianos/farmacologia , Gânglios da Base/efeitos dos fármacos , Benzotiazóis/farmacologia , Levodopa/análogos & derivados , Transtornos Parkinsonianos/tratamento farmacológico , Animais , Gânglios da Base/fisiopatologia , Benserazida/farmacologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/fisiopatologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Levodopa/farmacologia , Masculino , Atividade Motora/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Neurogênese/fisiologia , Oxidopamina , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/fisiopatologia , Pramipexol , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D3/metabolismo , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , Substância Negra/fisiopatologia , Fatores de Tempo
10.
Plant Foods Hum Nutr ; 69(4): 365-71, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25447553

RESUMO

The aim of this work was to study the effect of the addition of passion fruit pulp (PFP: 0-7%), the variation of barrel temperature in the third zone extruder (BT: 80-140 °C) and feed moisture (FM:16-30%) in a blend of corn starch and passion fruit pulp on different physicochemical characteristics of directly expanded snacks by extrusion technology. Single-screw laboratory extruder and a central, composite, rotatable experimental design were used. Expansion index of extrudates ranged between 1.0 and 1.8. Decreasing of feed moisture (18%), passion fruit pulp concentration (1.42%) and the increasing of barrel temperature (127 °C) resulted in higher expansion index. The increasing of feed moisture and passion fruit pulp concentration resulted in higher penetration force values of extrudates. The passion fruit pulp concentration showed a highly significant effect (p ≤ 0.01) on the L *, a * and b * parameters. Passion fruit pulp has a reasonable source of ß-carotene, proteins and dietary fibers that can be added to expanded snacks.


Assuntos
Dieta , Manipulação de Alimentos/métodos , Frutas , Passiflora , Lanches , Amido , Zea mays , Antioxidantes , Cor , Fibras na Dieta/análise , Proteínas Alimentares/análise , Frutas/química , Humanos , Valor Nutritivo , Passiflora/química , Temperatura , Água , beta Caroteno/análise
11.
Mol Psychiatry ; 17(6): 612-23, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21808255

RESUMO

Depression is a major health problem worldwide. Most prescribed anti-depressants, the selective serotonin reuptake inhibitors (SSRI) show limited efficacy and delayed onset of action, partly due to the activation of somatodendritic 5-HT(1A)-autoreceptors by the excess extracellular serotonin (5-HT) produced by SSRI in the raphe nuclei. Likewise, 5-HT(1A) receptor (5-HT(1A)R) gene polymorphisms leading to high 5-HT(1A)-autoreceptor expression increase depression susceptibility and decrease treatment response. In this study, we report on a new treatment strategy based on the administration of small-interfering RNA (siRNA) to acutely suppress 5-HT(1A)-autoreceptor-mediated negative feedback mechanisms. We developed a conjugated siRNA (C-1A-siRNA) by covalently binding siRNA targeting 5-HT(1A) receptor mRNA with the SSRI sertraline in order to concentrate it in serotonin axons, rich in serotonin transporter (SERT) sites. The intracerebroventricular (i.c.v.) infusion of C-1A-siRNA to mice resulted in its selective accumulation in serotonin neurons. This evoked marked anti-depressant-like effects in the forced swim and tail suspension tests, but did not affect anxiety-like behaviors in the elevated plus-maze. In parallel, C-1A-siRNA administration markedly decreased 5-HT(1A)-autoreceptor expression and suppressed 8-OH-DPAT-induced hypothermia (a pre-synaptic 5-HT(1A)R effect in mice) without affecting post-synaptic 5-HT(1A)R expression in hippocampus and prefrontal cortex. Moreover, i.c.v. C-1A-siRNA infusion augmented the increase in extracellular serotonin evoked by fluoxetine in prefrontal cortex to the level seen in 5-HT(1A)R knockout mice. Interestingly, intranasal C-1A-siRNA administration produced the same effects, thus opening the way to the therapeutic use of C-1A-siRNA. Hence, C-1A-siRNA represents a new approach to treat mood disorders as monotherapy or in combination with SSRI.


Assuntos
Antidepressivos/uso terapêutico , Autorreceptores/antagonistas & inibidores , Depressão/tratamento farmacológico , Combinação de Medicamentos , RNA Interferente Pequeno/uso terapêutico , Receptor 5-HT1A de Serotonina/genética , 8-Hidroxi-2-(di-n-propilamino)tetralina/antagonistas & inibidores , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Administração Intranasal , Animais , Autorreceptores/biossíntese , Modelos Animais de Doenças , Desenho de Fármacos , Fluoxetina/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipotermia/induzido quimicamente , Hipotermia/tratamento farmacológico , Infusões Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Receptor 5-HT1A de Serotonina/biossíntese , Receptor 5-HT1A de Serotonina/química , Neurônios Serotoninérgicos/efeitos dos fármacos , Neurônios Serotoninérgicos/metabolismo , Sertralina/administração & dosagem , Sertralina/química
12.
Gen Comp Endocrinol ; 188: 133-6, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23410915

RESUMO

The melanocortin system integrates different agonists, competitive or inverse agonists, and receptors. Recent investigations have also discovered a specific system of melanocortin receptor accessory proteins (MRAPs) that are involved in the regulation of the functional expression of these receptors. MRAP1 mutations are responsible for type 2 familial glucocorticoid deficiency (FGD2), a rare autosomal disorder characterized by high plasma adrenocorticotropin hormone (ACTH) levels but severe cortisol deficiency. ACTH binds melanocortin 2 receptor (MC2R), a G protein-coupled receptor, in the adrenal gland to promote corticosteroid synthesis. In the absence of MRAP1, MC2R cannot translocate from the endoplasmic reticulum to the plasma membrane and ACTH-induced signaling is extinguished. A second MRAP protein, called MRAP2, also modulates MC2R activity. MRAPs also interact with the other melanocortin receptors, adjusting their pharmacological properties. In this paper, we briefly review the MRAP system and its interaction with melanocortin receptors.


Assuntos
Proteínas de Membrana/metabolismo , Receptores de Melanocortina/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Animais , Humanos , Ligação Proteica , Receptor Tipo 1 de Melanocortina/metabolismo , Receptor Tipo 2 de Melanocortina/metabolismo
13.
Ecotoxicol Environ Saf ; 90: 157-66, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23352272

RESUMO

The Northwestern Portuguese region is densely populated and highly industrialized, suffering from high anthropogenic pressure. To assess the biological effect of the several pollutants that are constantly released to the water, a biomarker-based biomonitoring is a promising approach that may provide early-warning signals of pollutants exposure. Fish gill is the first target of pollutants action, thus histopathological and biochemical changes may constitute potential biomarkers. To evaluate this hypothesis, three native fish species (barbel-Luciobarbus bocagei, chub-Squalius carolitertii and nase-Pseudochondrostoma sp.) were sampled in Northwestern Portuguese rivers, the gill histopathological changes were qualitative and quantitatively analyzed and the lipid peroxidation and glutathione-S-transferase activity were determined. A multivariate statistical analysis was performed to establish correlations between these biological responses, environmental variables and ecological status. The quantitative evaluation of the main histopathological changes and oxidative stress responses emphasize the differences, among species, in the responses to the presence of contaminants in water. Discriminant canonical analysis showed that filament epithelium proliferation, necrosis and GST activity were the main contributors to discriminate the ecological status classification. In addition, the results showed that a wide range of environmental factors are influencing fish physiology. In conclusion, the gill biological responses, although not reflecting specific contaminants, can be used as biomarkers of ecosystems perturbation.


Assuntos
Monitoramento Ambiental , Peixes/fisiologia , Brânquias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Rios , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/análise , Ativação Enzimática/efeitos dos fármacos , Brânquias/química , Brânquias/patologia , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Portugal , Poluentes Químicos da Água/análise
14.
Nano Lett ; 12(9): 4869-74, 2012 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-22871166

RESUMO

The ability to control the formation of interfaces between different materials has become one of the foundations of modern materials science. With the advent of two-dimensional (2D) crystals, low-dimensional equivalents of conventional interfaces can be envisioned: line boundaries separating different materials integrated in a single 2D sheet. Graphene and hexagonal boron nitride offer an attractive system from which to build such 2D heterostructures. They are isostructural, nearly lattice-matched, and isoelectronic, yet their different band structures promise interesting functional properties arising from their integration. Here, we use a combination of in situ microscopy techniques to study the growth and interface formation of monolayer graphene-boron nitride heterostructures on ruthenium. In a sequential chemical vapor deposition process, boron nitride grows preferentially at the edges of existing monolayer graphene domains, which can be exploited for synthesizing continuous 2D membranes of graphene embedded in boron nitride. High-temperature growth leads to intermixing near the interface, similar to interfacial alloying in conventional heterostructures. Using real-time microscopy, we identify processes that eliminate this intermixing and thus pave the way to graphene-boron nitride heterostructures with atomically sharp interfaces.


Assuntos
Compostos de Boro/química , Cristalização/métodos , Grafite/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Substâncias Macromoleculares/química , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
15.
J Craniomaxillofac Surg ; 51(7-8): 467-474, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37550116

RESUMO

The aim of this study was to assess the diagnostic accuracy of single photon emission tomography (SPECT) in unilateral condylar hyperplasia (UCH). To this end, 3D morphometric changes of the mandibles in one year were assessed (T0 vs. T1) and compared over SPECT results in T1, in a sample of 40 patients. A contingency table was constructed based on these results for SPECT diagnostic accuracy evaluation, classifying patients as SPECT true-positive, true-negatives, false positives and false-negatives. Additionally, the morphometric analysis was used to describe the presentation of mandibular changes using principal component analysis (PCA) and non-parametric statistics. We obtained diagnostic accuracy results of sensitivity 81%, specificity 63%, positive predictor value (PPV) 59%, negative predictor value (NPV) 83% and accuracy 70%, showing that SPECT yields poor results regarding accuracy diagnostic performance. The morphometric analysis showed that individuals without progress of asymmetry and those with more progress differ particularly in a group of landmarks representing the mental region and the right mandibular body. Based on these landmarks, difference among the four SPECT-accuracy groups was statistically significant (p < 0.001), where the landmark showing the largest change within a year had a mean increase of 1.13 + 0.66 mm. Within the limitations of the study, it seems that SPECT alone is not suitable for making surgical decisions regarding condylectomy in active UCH. Follow up with morphological assessment methods are recommended for confirming an active UCH in combination with SPECT.


Assuntos
Côndilo Mandibular , Doenças Estomatognáticas , Humanos , Estudos Retrospectivos , Hiperplasia/diagnóstico por imagem , Hiperplasia/patologia , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/cirurgia , Côndilo Mandibular/patologia , Tomografia Computadorizada de Emissão de Fóton Único , Mandíbula/diagnóstico por imagem , Assimetria Facial/cirurgia
16.
Phys Rev Lett ; 108(9): 097002, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22463660

RESUMO

Employing the momentum sensitivity of time- and angle-resolved photoemission spectroscopy we demonstrate the analysis of ultrafast single- and many-particle dynamics in antiferromagnetic EuFe(2)As(2). Their separation is based on a temperature-dependent difference of photoexcited hole and electron relaxation times probing the single-particle band and the spin density wave gap, respectively. Reformation of the magnetic order occurs at 800 fs, which is 4 times slower compared to electron-phonon equilibration due to a smaller spin-dependent relaxation phase space.

17.
Phys Rev Lett ; 107(9): 097002, 2011 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-21929262

RESUMO

The nonequilibrium state of the high-T(c) superconductor Bi(2)Sr(2)CaCu(2)O(8+δ) and its ultrafast dynamics have been investigated by femtosecond time- and angle-resolved photoemission spectroscopy well below the critical temperature. We probe optically excited quasiparticles at different electron momenta along the Fermi surface and detect metastable quasiparticles near the antinode, since their decay toward the nodal region through e-e scattering is blocked by phase space restrictions. The observed lack of momentum dependence in the decay rates is in agreement with relaxation dynamics dominated by Cooper pair recombination in a boson bottleneck limit.

18.
Med Intensiva ; 35(7): 417-23, 2011 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-21620524

RESUMO

OBJECTIVE: To analyze mortality and resource consumption in patients with long stays in pediatric intensive care units (PICUs). DESIGN: A retrospective, descriptive case series study. SCOPE: Medical-surgical PICU in a third level hospital. PATIENTS: Data were collected from patients with a stay of 28 days or more in PICU between 2006 and 2010. Of the 2118 patients assisted in this period, 83 (3.9%) required prolonged stay. STUDY VARIABLES: Morbidity-mortality and resource consumption among patients with prolonged stay in the PICU. RESULTS: Mortality was higher in patients with a long stay (22.9%) than in the rest of patients (2%) (p<0.001). In 52.6% of these patients, death occurred after withdrawal of treatment or after not starting resuscitation measures. Patients with prolonged stay showed a high incidence of nosocomial infection (96.3%) and an important consumption of healthcare resources (97.6% required conventional mechanical ventilation, 90.2% required transfusion of blood products, 86.7% required intravenous vasoactive drugs and 22.9% required extracorporeal membrane oxygenation [ECMO]). CONCLUSIONS: Critical children with prolonged stay in the PICU show important morbidity and mortality, and an important consumption of healthcare resources. The adoption of specific measures permitting early identification of patients at risk of prolonged stay is needed in order to adapt therapeutic measures and available resources, and to improve treatment efficiency.


Assuntos
Estado Terminal/mortalidade , Recursos em Saúde/estatística & dados numéricos , Mortalidade Hospitalar , Unidades de Terapia Intensiva/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Pediatria , Adolescente , Transfusão de Sangue/economia , Transfusão de Sangue/estatística & dados numéricos , Causas de Morte , Criança , Pré-Escolar , Anormalidades Congênitas/economia , Anormalidades Congênitas/mortalidade , Infecção Hospitalar/economia , Infecção Hospitalar/mortalidade , Uso de Medicamentos/economia , Feminino , Hospitais Gerais/economia , Hospitais Gerais/estatística & dados numéricos , Hospitais Universitários/economia , Hospitais Universitários/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva/economia , Tempo de Internação/economia , Masculino , Pediatria/economia , Complicações Pós-Operatórias/economia , Complicações Pós-Operatórias/mortalidade , Respiração Artificial/economia , Respiração Artificial/estatística & dados numéricos , Estudos Retrospectivos , Espanha/epidemiologia , Suspensão de Tratamento/estatística & dados numéricos
19.
Sci Total Environ ; 771: 144768, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33524681

RESUMO

The longitudinal dimension of river connectivity has been significantly disrupted by barriers to compensate for water demand in the long periods of water scarcity in the Iberian Peninsula. The scale of this modification is widespread in the Portuguese part of Douro River network where, side to side with agriculture water demand, there is a constant increase in hydropower production. Thus, native species in Iberian freshwater systems, performing reproductive migrations along the rivers, are strongly affected by the amplification of fragmentation caused by the tremendous density of transversal obstacles in this river basin. We aimed to prioritize dam removal in the Portuguese part of Douro River, mainly considering obsolete barriers (small dams, weirs) based on a spatial multicriteria decision analysis (GIS-MCDA) based on a prioritization procedure. A diversity of parameters were used to prioritize (rank) the dam's suitability for removal, considering the losses of connectivity and fish biodiversity, habitat degradation, negative effects on water quality and ecological conditions, and socio-economic factors. Different weights were assigned to the different attributes in each criterion according to their importance. The analysis also included a significant constraint: the potential spreading of exotic invasive fish species if connection was reestablished through dam removal. This procedure started with the georeferencing of 1201 transversal obstacles that were further characterized for their relative permeability to fish migration. In conclusion the model used allowed to identify 158 priority barriers, as well as the 5 most fragmented tributaries, which means the most impacted by river regulation. In 8 cases the barriers were big dams (> 15 m), whereas in the remaining 150 were weirs. From a final rank of 20 most impacting structures, the MCDA results also identified two cases where potential removal could trigger the additional impact to native fish species related to the sprawl of alien populations.


Assuntos
Peixes , Rios , Animais , Biodiversidade , Ecossistema , Europa (Continente)
20.
Sci Total Environ ; 764: 142869, 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33129522

RESUMO

The Vilariça River (located in the northeast of Portugal) is inserted in an agricultural basin and it was chosen to replace the spawning grounds for fish, that was lost due to the construction of dams in the Sabor River. Thus, it is essential to study the effect of agricultural practices on water quality and in the health status of fish. The barbel (Luciobarbus bocagei) and Douro nase (Pseudochondrostoma duriense) were the selected species and the work was developed in two seasons (Summer 2016 and Winter 2017). For that, the histopathological changes of fish gill were used as biomarkers, through a semi-quantitative approach that considers the injuries severity. And the water quality assessment criteria followed the methodologies proposed for classifying the status of surface water bodies from Portugal. The current study showed severe histopathological changes in both species and both seasons, and the water was classified as polluted and extremely polluted in Summer and Winter respectively. The pollution in Summer was due to high temperatures, low dissolved oxygen and major concentration of As and Mn, and in Winter is due to the high concentration of Total Suspended Solids, nitrites and Cd. The increase of values of physico-chemical parameters on the water was caused by the less streamflow and excessive agricultural fertilization in Summer which arrive the river by irrigation, and by the erosion of soil particles with heavy metals associated in Winter. Also, the canonical analysis showed that physico-chemical parameters concentrations in Summer justify the major prevalence of aneurism in barbel and exudate in nase and Winter the major prevalence of hypertrophy in barbel. In conclusion, the study showed that the gill injuries of barbel and Douro nase was correlated with the water quality and it is influenced by seasonal agricultural practices and the flow regime.


Assuntos
Cyprinidae , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Brânquias/química , Portugal , Rios , Estações do Ano , Poluentes Químicos da Água/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA