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1.
J Neurosci ; 43(18): 3245-3258, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-36948583

RESUMO

Mirror-image pain arises from pathologic alterations in the nociceptive processing network that controls functional lateralization of the primary afferent input. Although a number of clinical syndromes related to dysfunction of the lumbar afferent system are associated with the mirror-image pain, its morphophysiological substrate and mechanism of induction remain poorly understood. Therefore, we used ex vivo spinal cord preparation of young rats of both sexes to study organization and processing of the contralateral afferent input to the neurons in the major spinal nociceptive projection area Lamina I. We show that decussating primary afferent branches reach contralateral Lamina I, where 27% of neurons, including projection neurons, receive monosynaptic and/or polysynaptic excitatory drive from the contralateral Aδ-fibers and C-fibers. All these neurons also received ipsilateral input, implying their involvement in the bilateral information processing. Our data further show that the contralateral Aδ-fiber and C-fiber input is under diverse forms of inhibitory control. Attenuation of the afferent-driven presynaptic inhibition and/or disinhibition of the dorsal horn network increased the contralateral excitatory drive to Lamina I neurons and its ability to evoke action potentials. Furthermore, the contralateral Aßδ-fibers presynaptically control ipsilateral C-fiber input to Lamina I neurons. Thus, these results show that some lumbar Lamina I neurons are wired to the contralateral afferent system whose input, under normal conditions, is subject to inhibitory control. A pathologic disinhibition of the decussating pathways can open a gate controlling contralateral information flow to the nociceptive projection neurons and, thus, contribute to induction of hypersensitivity and mirror-image pain.SIGNIFICANCE STATEMENT We show that contralateral Aδ-afferents and C-afferents supply lumbar Lamina I neurons. The contralateral input is under diverse forms of inhibitory control and itself controls the ipsilateral input. Disinhibition of decussating pathways increases nociceptive drive to Lamina I neurons and may cause induction of contralateral hypersensitivity and mirror-image pain.


Assuntos
Corno Dorsal da Medula Espinal , Medula Espinal , Feminino , Masculino , Ratos , Animais , Dor , Fibras Nervosas Amielínicas/fisiologia , Interneurônios , Nociceptores/fisiologia , Neurônios Aferentes/fisiologia , Vias Aferentes/fisiologia
2.
J Neurosci ; 42(17): 3587-3598, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35318285

RESUMO

Cervical and trigeminal afferents innervate neighboring cranial territories, and their convergence on upper cervical dorsal horn neurons provides a potential substrate for pain referral in primary headache syndromes. Lamina I neurons are central to this mechanism, as they relay convergent nociceptive input to supraspinal pain centers. Unfortunately, little is known about the interactions between trigeminal and cervical afferents supplying Lamina I neurons. Here, we used rats of both sexes to show that cervical and trigeminal afferents interact via presynaptic inhibition, where monosynaptic inputs to Lamina I neurons undergo unidirectional as well as reciprocal presynaptic control. This means that afferent-driven presynaptic inhibition shapes the way trigeminal and cervical Aδ-fiber and C-fiber input reaches Lamina I projection neurons (PNs) and local-circuit neurons (LCNs). We propose that this inhibition provides a feedforward control of excitatory drive to Lamina I neurons that regulates their convergent and cervical-specific or trigeminal-specific processing modes. As a consequence, disruption of the trigeminal and cervical afferent-driven presynaptic inhibition may contribute to development of primary headache syndromes.SIGNIFICANCE STATEMENT Cervical and trigeminal afferents innervate neighboring cranial territories, and their convergence on upper cervical dorsal horn neurons provides a potential substrate for pain referral in primary headache syndromes. Lamina I neurons are central to this mechanism as they relay convergent nociceptive input to supraspinal pain centers. Here, we show that cervical and trigeminal afferents interact via presynaptic inhibition, where inputs to Lamina I neurons undergo unidirectional as well as reciprocal control. The afferent-driven presynaptic inhibition shapes the trigeminocervical Aδ-fiber and C-fiber input to Lamina I neurons. This inhibition provides control of excitatory drive to Lamina I neurons that regulates their convergent and cervical-specific or trigeminal-specific processing modes. Disruption of this control may contribute to development of primary headache syndromes.


Assuntos
Transtornos da Cefaleia , Nociceptividade , Animais , Feminino , Masculino , Fibras Nervosas Amielínicas/fisiologia , Neurônios Aferentes/fisiologia , Nociceptividade/fisiologia , Dor , Ratos , Corno Dorsal da Medula Espinal/fisiologia
3.
Brain ; 145(5): 1632-1640, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35661858

RESUMO

The axon initial segment is a specialized compartment of the proximal axon of CNS neurons where action potentials are initiated. However, it remains unknown whether this domain is assembled in sensory dorsal root ganglion neurons, in which spikes are initiated in the peripheral terminals. Here we investigate whether sensory neurons have an axon initial segment and if it contributes to spontaneous activity in neuropathic pain. Our results demonstrate that myelinated dorsal root ganglion neurons assemble an axon initial segment in the proximal region of their stem axon, enriched in the voltage-gated sodium channels Nav1.1 and Nav1.7. Using correlative immunofluorescence and calcium imaging, we demonstrate that the Nav1.7 channels at the axon initial segment are associated with spontaneous activity. Computer simulations further indicate that the axon initial segment plays a key role in the initiation of spontaneous discharges by lowering their voltage threshold. Finally, using a Cre-based mouse model for time-controlled axon initial segment disassembly, we demonstrate that this compartment is a major source of spontaneous discharges causing mechanical allodynia in neuropathic pain. Thus, an axon initial segment domain is present in sensory neurons and facilitates their spontaneous activity. This study provides a new insight in the cellular mechanisms that cause pathological pain and identifies a new potential target for chronic pain management.


Assuntos
Segmento Inicial do Axônio , Neuralgia , Animais , Gânglios Espinais/patologia , Humanos , Hiperalgesia/patologia , Camundongos , Neuralgia/patologia , Células Receptoras Sensoriais
4.
Exp Parasitol ; 246: 108464, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36682720

RESUMO

This study aimed to evaluate histological, digestive and postabsorptive physiological parameters in Santa Ines lambs infected with Trichostrongylus colubriformis and fed different levels of phosphorus. Therefore, eighteen Santa Ines, castrated male, six-month old, healthy lambs (initial body weight 22.4 ± 2.7 kg) were distributed in one of four treatments arranged in a 2 × 2 split-plot arrangement: Sufficient dietary P level and uninfected (SPui; n = 4), Sufficient dietary P level and infected (SPi; n = 5), Deficient dietary P level and uninfected (DPui; n = 4), Deficient dietary P level and infected (DPi; n = 5). Infected lambs received, orally, a single pulse dose of 40.000 T. colubriformis infective larval stage (L3). Animals were fed Tifton 85 hay (Cynodon ssp.; 60%), and cassava meal and maize gluten meal (40%). Measurement of nutrient apparent digestibility and nitrogen metabolism were performed in individual metabolic stalls. To achieve the trial results, it was measured methane emissions in respiratory chambers, urine purine derivatives, ruminal short-chain fatty acids (SCFA), histological cuts of duodenal mucosal tissues and passage rates fluxes, analyzed by external (Yb, Cr, and Co) and internal (iNDF) markers. Statistical procedures were performed in R studio. The fixed main effects of treatment and the interactions were tested by ANOVA, and means compared by Duncan's test at 5% significance. Apparent digestibility was not affected by treatments, however, nitrogen retained decreased (P < 0.01) and urinary nitrogen losses increased (P < 0.01) in infected animals. Small intestine digesta content, empty segment weight, and length were higher in infected animals (P < 0.05). Passage rate was not majorly affected by infection or dietary P levels. Methane emissions, SCFA concentrations, and purine derivative excretion were also not affected by treatments. Regarding the histology, the vilosity weight (P < 0.05), and crypt depth (P < 0.01) decreased in infected animals. In conclusion, T. colubriformis infection can damage intestinal mucosa and affect nitrogen metabolism, but did not affect the digesta transit, and nutrient digestibility. The P dietary levels did not promote any modification in GIT physiological parameters tested in this study.


Assuntos
Doenças dos Ovinos , Tricostrongilose , Animais , Masculino , Ração Animal , Duodeno/metabolismo , Fezes , Metano , Nitrogênio/metabolismo , Ovinos , Doenças dos Ovinos/metabolismo , Doenças dos Ovinos/parasitologia , Tricostrongilose/veterinária , Tricostrongilose/metabolismo , Trichostrongylus/fisiologia , Absorção Intestinal , Fosfatos/administração & dosagem , Fosfatos/metabolismo
5.
Anal Bioanal Chem ; 414(8): 2571-2583, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35088131

RESUMO

This research proposes a low-cost and simple operation microfluidic chip to enhance the magnetic labeling efficiency of two ischemic stroke biomarkers: cellular fibronectin (c-Fn) and matrix metallopeptidase 9 (MMP9). This fully portable and pump-free microfluidic chip is operated based on capillary attractions without any external power source and battery. It uses an integrated cellulose sponge to absorb the samples. At the same time, a magnetic field is aligned to hold the target labeled by the magnetic nanoparticles (MNPs) in the pre-concentrated chamber. By using this approach, the specific targets are labeled from the beginning of the sampling process without preliminary sample purification. The proposed study enhanced the labeling efficiency from 1 h to 15 min. The dynamic interactions occur in the serpentine channel, while the crescent formation of MNPs in the pre-concentrated chamber, acting as a magnetic filter, improves the biomarker-MNP interaction. The labeling optimization by the proposed device influences the dynamic range by optimizing the MNP ratio to fit the linear range across the clinical cutoff value. The limits of detection (LODs) of 2.8 ng/mL and 54.6 ng/mL of c-Fn measurement were achieved for undiluted and four times dilutions of MNP, respectively. While for MMP9, the LODs were 11.5 ng/mL for undiluted functionalized MNP and 132 ng/mL for four times dilutions of functionalized MNP. The results highlight the potential use of this device for clinical sample preparation and specific magnetic target labeling. When combined with a detection system, it could also be used as an integrated component of a point-of-care platform.


Assuntos
AVC Isquêmico , Dispositivos Lab-On-A-Chip , Biomarcadores , Humanos , Fenômenos Magnéticos , Microfluídica
6.
Ann Gen Psychiatry ; 20(1): 35, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34229687

RESUMO

BACKGROUND: Suicide is one of the main causes of excess of premature death in psychotic patients. Published studies found that suicide risk begins in ultra-high risk of psychosis and continues in early years of the disease. Previous studies identifying predictive and risk factors associated with suicidality in first-episode psychosis (FEP) are highly inconsistent. Also, there are relatively few longitudinal studies on suicidal behaviour in FEP. The aim of this study was to examine prevalence, evolution and predictors of suicidal behaviour at baseline and the 12-month follow-up in patients presenting with FEP. METHODS: One hundred and eighteen patients presenting with FEP were recruited from two early psychosis units in Portugal. A comprehensive assessment examining socio-demographic and clinical characteristics was administered at baseline and the 12-month follow-up. Odds ratio were calculated using logistic regression analyses. McNemar test was used to evaluate the evolution of suicidal behaviour and depression prevalence from baseline to 12 months of follow-up. RESULTS: Follow-up data were available for 60 participants from the 118 recruited. Approximately 25.4% of the patients had suicidal behaviour at the baseline evaluation, with a significant reduction during the follow-up period to 13.3% (p = 0.035). A multivariate binary logistic regression showed that a history of suicidal behaviour and depression at baseline independently predicted suicidal behaviour at baseline, and a history of suicidal behaviour and low levels of total cholesterol predicted suicidal behaviour at the 12-month follow-up. A significant proportion of patients also had depression at the baseline evaluation (43.3%), with the last month of suicidal behaviour at baseline independently predicting depression at this time. CONCLUSIONS: The findings of our study indicate that suicidal behaviour was prevalent on the year after FEP. Patients with a history of suicidal behaviour, depression at baseline and low levels of cholesterol should undergo close evaluation, monitoring and possible intervention in order to reduce suicide risk in the early phases of psychosis.

7.
Rheumatology (Oxford) ; 59(12): 3717-3726, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32393983

RESUMO

OBJECTIVES: To compare the ultrasound characteristics with clinical features, final diagnosis and outcome; and to evaluate the halo size following glucocorticoid treatment in patients with newly diagnosed GCA. METHODS: Patients with suspected GCA, recruited from an international cohort, had an ultrasound of temporal (TA) and axillary (AX) arteries performed within 7 days of commencing glucocorticoids. We compared differences in clinical features at disease presentation, after 2 weeks and after 6 months, according to the presence or absence of halo sign. We undertook a cross-sectional analysis of the differences in halo thickness using Pearson's correlation coefficient (r) and Analysis of Variance (ANOVA). RESULTS: A total of 345 patients with 6 months follow-up data were included; 226 (65.5%) had a diagnosis of GCA. Jaw claudication and visual symptoms were more frequent in patients with halo sign (P =0.018 and P =0.003, respectively). Physical examination abnormalities were significantly associated with the presence of ipsilateral halo (P <0.05). Stenosis or occlusion on ultrasound failed to contribute to the diagnosis of GCA. During 7 days of glucocorticoid treatment, there was a consistent reduction in halo size in the TA (maximum halo size per patient: r=-0.30, P =0.001; and all halos r=-0.23, P <0.001), but not in the AX (P >0.05). However, the presence of halo at baseline failed to predict future ischaemic events occurring during follow-up. CONCLUSION: In newly diagnosed GCA, TA halo is associated with the presence of ischaemic features and its size decreases following glucocorticoid treatment, supporting its early use as a marker of disease activity, in addition to its diagnostic role.


Assuntos
Arterite de Células Gigantes/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Arterite de Células Gigantes/tratamento farmacológico , Arterite de Células Gigantes/epidemiologia , Glucocorticoides/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Prednisolona/uso terapêutico , Ultrassonografia
8.
Nanomedicine ; 30: 102287, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32798732

RESUMO

The abundance of cellular fibronectin (c-Fn) for ischemic stroke patients and the narrow time-window (<4.5 h) for the decision to administer the thrombolytic treatment with recombinant tissue plasminogen activator (rtPA) are challenging for the development of a point-of-care (PoC) diagnostic platform. We report a case of stratification of ischemic stroke patients based on a magnetoresistive biosensor platform that quantifies the c-Fn levels in a small volume of serum, within the clinically relevant time-window. Our PoC platform uses different ratios of biofunctionalized magnetic nanoparticles (MNPs) as immunoassay labels to adjust the sensitivity within the clinically relevant ranges for c-Fn (1-4 µg/mL). After optimizing the detection range, resolution, and sensitivity, our device was able to stratify ischemic stroke patients who developed hemorrhagic transformation, the main side-effect of rtPA, from those (both non-treated and treated with rtPA) who did not.


Assuntos
Isquemia Encefálica/sangue , Fibronectinas/sangue , Sistemas Automatizados de Assistência Junto ao Leito , Acidente Vascular Cerebral/sangue , Idoso , Estudos de Coortes , Feminino , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade
9.
Aging Ment Health ; 23(8): 1049-1056, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-29791197

RESUMO

Objectives: Self-perceived health declines with age, varies by gender and is a predictor of mortality, morbidity, physical and psychological functioning. However, gender differences in health and illness perception are complex and not yet fully understood. This study aimed to explore gender-related differences in psychosocial determinants of self-perceived health among older adults living in nursing homes. Method: Nationwide face-to-face survey of the Portuguese population aged 65 and over. A representative sample of nursing homes residents was obtained through a multistage cluster random sampling of nursing homes, stratified by main Portuguese administrative regions (NUTS II). Results: Overall, 1186 nursing homes residents voluntarily enrolled in this study (participation rate, 93%) and a total of 515 participants (70.1% women) were considered to have adequate cognitive functioning to answer all questionnaires. A significant association between self-rated health and gender was found: 90.6% of all women (95% CI: 85.7-93.9) and 82.3% of all men (95% CI: 72.9-88.9) rated their health as less than good (p = 0.023). Gender-stratified analyses showed differences in psychosocial determinants of self-perceived health. While symptoms of depression and loneliness feelings were the major psychosocial determinants of poor self-perceived health among women, age and subjective financial well-being were the only determinants among men. Conclusion: Factors associated with perceived health, as representative of healthy ageing, were identified by gender, leading to future avenues for fruitful investigation. The acknowledgement of interpersonal and socioeconomic factors that determine the experience of ageing at a national level is crucial to improve the health of elders.


Assuntos
Envelhecimento/psicologia , Autoavaliação Diagnóstica , Instituição de Longa Permanência para Idosos , Casas de Saúde , Idoso , Idoso de 80 Anos ou mais , Depressão/psicologia , Feminino , Humanos , Solidão/psicologia , Masculino , Satisfação Pessoal , Portugal , Fatores Sexuais , Classe Social
10.
Analyst ; 142(6): 979-986, 2017 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-28247879

RESUMO

Microvesicles (MVs) are a promising source of diagnostic biomarkers which have gained a wide interest in the biomedical and biosensing field. They can be interpreted as a "fingerprint" of various diseases. Nonetheless, MVs implementation into clinical settings has been hampered by the lack of technologies to accurately characterize, detect and quantify them. Here, we report the specific sensing and quantification of MVs from endothelial cells using a portable magnetoresistive (MR) biochip platform, in less than one hour and within physiologically relevant concentrations (1 × 108 MVs per ml). MVs were isolated from both endothelial and epithelial cells undergoing apoptosis, and characterized by atomic force microscopy (AFM) and nanoparticle tracking analysis (NTA), which revealed similar MV sizes. Importantly, our results showed that the two distinct MV populations could be discriminated with the MR biochip platform, with over a 5-fold capture efficiency of endothelial MVs in comparison to the control (epithelial MVs). Also, unspecific binding of MVs to BSA was less than 1% of the specific signal. The detection strategy was based on a sandwich immunoassay, where MVs were labelled with magnetic nanoparticles (MNPs) functionalized with Annexin V and then captured by anti-CD31 antibodies previously immobilized on the surface of the sensor. Results suggest that this approach allows the detection of specific MVs from complex samples such as serum, and highlight the potential of this technology to become a suitable tool for MVs detection as a complementary method of diagnosis.


Assuntos
Micropartículas Derivadas de Células , Células Endoteliais da Veia Umbilical Humana/citologia , Imunoensaio , Nanopartículas , Anexina A5 , Apoptose , Células Endoteliais , Humanos , Microscopia de Força Atômica
11.
Anal Chem ; 87(7): 3699-705, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25723904

RESUMO

Instrumental neutron activation analysis with both relative and k0 standardization was used in four experienced laboratories to determine element mass fractions in single-wall carbon nanotube certified reference material (CRM) SWCNT-1. Results obtained were evaluated using the National Institute of Standards and Technology (NIST) "Type B On Bias" approach and yielded consensus values in agreement with National Research Council Canada (NRCC) certified values for Fe, Co, Ni, and Mo and provided mass fraction values for 13 additional elements, namely, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Br, La, W, and Au. In addition, prompt γ neutron activation analysis was employed to determine mass fractions of H, B, Co, Ni, and Mo. Results of this work provide a basis for the establishment of reference values of element mass fractions in CRM SWCNT-1, thus expanding its usability for more accurate characterization and benchmarking of similar nanotechnology materials.

12.
Electrophoresis ; 36(23): 2902-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26333169

RESUMO

Esophageal cancers (ECs) show poor prognosis and decreased overall survival due to late diagnosis and ineffective therapeutics, urging the introduction of novel biomarkers to aid disease management. The levels of sialyl-Lewis(a) antigen (sLe(a) ) are frequently increased in digestive tumours, which has been explored in serological non-invasive prognostication (CA19-9 test); however, with low sensitivity and specificity. Autoantibodies against cancer antigens are considered the next generation biomarkers, as they are present in circulation long before tumour-associated proteins. Based on these observations we have mined the serum of EC patients (n = 7) for antibodies against sLe(a) -glycosylated protein species. All EC were positive for sLe(a) , irrespectively of their histological nature but only two patients showed elevated CA19-9. Moreover, IgG titers, with emphasis on IgG1, were elevated in EC patients in comparison to the control group. SLe(a) -glycoproteins were then extracted from tumours of patients with negative CA19-9, isolated by immunoprecipitation and blotted with patients IgG. Autoantibodies against sLe(a) -glycosylated proteins were detected in all cases. Different SLe(a) -glycoproteins were observed for tumours of distinct histological natures, which now require identification and validation in larger patient sets. This preliminary data suggests that antoantibodies against sLe(a) glycosylated proteins hold potential for non-invasive diagnosis in CA19-9 negative cases and sets the rational for future immunoproteomic studies envisaging highly specific EC biomarkers.


Assuntos
Neoplasias Esofágicas/imunologia , Gangliosídeos/metabolismo , Glicoproteínas/imunologia , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/imunologia , Biomarcadores Tumorais/imunologia , Biomarcadores Tumorais/metabolismo , Antígeno CA-19-9/metabolismo , Glicoproteínas/metabolismo , Glicosilação , Humanos , Imunidade Humoral , Imunoglobulina G/sangue , Imunoglobulina G/metabolismo , Masculino , Pessoa de Meia-Idade
13.
Animals (Basel) ; 13(6)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36978548

RESUMO

The poultry sector is one of the most important food industries in the world. Poultry production generates high-value protein products (meat and eggs) that are produced efficiently without the need for large areas. In poultry production, especially in the tropics, environmental factors, such as temperature and humidity, play a major role. Heat stress (HS) causes behavioral, physical, and physiological changes in poultry, with severe financial impacts. Therefore, it is important to find strategies to minimize it. The naked neck (Na) is an autosomal, incompletely dominant gene. Compared with normal feathered birds, these animals are known for their ability to adapt, perform, and reproduce under hot and humid climate conditions. Due to the absence of feathers on the neck, these animals increase heat dissipation, alleviating adverse heat effects, especially on productive performance. Genetic improvement of heat tolerance may provide a low-cost solution, of particular interest for developing countries in the tropics. The focus of this review is to evaluate the impact of HS in poultry with a special emphasis on the advantages of using the Na gene.

14.
Vet Parasitol ; 315: 109887, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36731211

RESUMO

Phosphorus (P) is one of the main minerals present in the animal body and exerts crucial functions in the organism. P is present at all cell membranes and integrates the structure of bones, being necessary its supplementation in ruminants due to the deficiency of this mineral in the pastures. One of the principal factors that compromise its metabolization are gastrointestinal nematodes (GIN). Thus, the objective of this study was evaluate the performance and metabolism of P through its distribution in the animal body, density of bones and muscles, dynamic fluxes, biological availability and half live of P, concentration of P in tissues and bones of lambs simultaneously infected with the most prevalent GIN to sheep, in tropical or subtropical areas, (Haemonchus contortus and Trichostrongylus colubriformis) using the isotopic dilution technique with 32P radioisotope. Twenty Santa Ines sheep with seven months of age and averaging initial weight of 30.8 ± 6.41 kg were used and allocated to one of two treatments. Ten animals were orally infected (a single dose of 30,000 L3 larvae of T. colubriformis + 10,000 L3 larvae of H. contortus), and ten animals were not infected (control group). During the experimental, samples of blood, feces, urine, and diet refusals were collected and weighting were performed. A computed tomography was performed twice, before infection and at the end of the experiment, to evaluate changes in body composition. On 64-d after experimental infection, animals received an intravenous injection of 32P solution, and 7-d after they received radioisotope injection. The experimental animals were slaughtered, and tissue and bones were collected for P concentrations. The results showed that the parasitic infection compromised the absorption of P, impairing the metabolism, decreasing the mineral bioavailability increasing P bones reabsorption, and reducing bones density, also negatively compromising the infected animal performance.


Assuntos
Coinfecção , Hemoncose , Haemonchus , Nematoides , Doenças dos Ovinos , Tricostrongilose , Ovinos , Animais , Trichostrongylus/fisiologia , Tricostrongilose/veterinária , Tricostrongilose/parasitologia , Fósforo , Coinfecção/veterinária , Hemoncose/veterinária , Fezes/parasitologia , Tomografia , Doenças dos Ovinos/diagnóstico por imagem , Doenças dos Ovinos/parasitologia , Contagem de Ovos de Parasitas/veterinária
15.
Acta Med Port ; 36(12): 792-801, 2023 Dec 04.
Artigo em Português | MEDLINE | ID: mdl-37421145

RESUMO

INTRODUCTION: Like in other countries, the age pyramid in Portugal has been changing considerably, with a substantial increase in the size of the older population and a significant reduction in the number of young people. With aging, co-occurrence of several conditions becomes frequent, often leading to the use of multiple medications (polypharmacy). Polypharmacy in the older population is particularly relevant considering the physiological changes of the ageing process, which increase the risk of drug interactions, poor adherence to treatment, and adverse drug reactions, especially in the oldest-old population (85 years or older). As the size of the older population is likely to increase significantly, it is important to characterize the pattern of medicines' use by the elderly while also identifying cases of polypharmacy in order to obtain evidence that can be used to develop specific measures to tackle the high prevalence of use and its associated risks. To this end, the aim of this study was to characterize medication use by older individuals in Portugal. METHODS: Cross-sectional study with data from the National Health System's Control and Monitoring Center on reimbursed medicines that were prescribed and dispensed to individuals aged 65 years or older in 2019 in all community pharmacies of the Portuguese mainland. We performed a demographic and geographic analysis of the data by international nonproprietary name and therapeutic group. The number of reimbursed packages and the number of reimbursed packages per capita were the metrics used (data from Instituto Nacional de Estatística). RESULTS: A higher consumption of medicines was observed in women, increasing with age, except in the oldest olds, in which the sex difference tended to shrink. Use per capita showed an opposite trend, with the oldest-old men surpassing the oldest-old women (mean reimbursed packages: 55.5 in men versus 55.1 in women). In women, consumption was led by cardiovascular medicines (31%), followed by central nervous system medications (30%) and antidiabetics (13%); in men, 37% of TOP 10 consumption was due to cardiovascular medications, antidiabetics (16%) and drugs for benign prostatic hypertrophy (14%). CONCLUSION: In the elderly, there were sex differences in the pattern of medicines' use, and there were also significant age-related differences in 2019. To the best of our knowledge, our study is the first nationwide analysis of reimbursed medicines' consumption data in the elderly, which is essential to characterize the use of medicines in this age group in Portugal.


Introdução: À semelhança de outros países, a pirâmide etária em Portugal tem sofrido alterações profundas, com um expressivo aumento na dimensão da população idosa. A multimorbilidade que surge com o envelhecimento leva, frequentemente, à utilização concomitante de vários medicamentos. A polimedicação é particularmente importante no idoso devido às alterações fisiológicas associadas ao processo de envelhecimento, que aumentam o risco de interações medicamentosas, de fraca adesão à terapêutica e de reações adversas à medicação, em particular nos indivíduos muito idosos (85 ou mais anos). Dado que a dimensão da população idosa poderá aumentar significativamente, importa caracterizar o padrão de consumo de medicamentos pelos idosos, identificando também os casos de polifarmácia, de forma a gerar-se evidência que permita o desenvolvimento de medidas específicas de combate à elevada prevalência de utilização e riscos associados. Assim, o objetivo desta análise preliminar foi determinar a prevalência e caracterizar do padrão de utilização de medicamentos pelos idosos em Portugal, desagregando por faixa etária, sexo e localização geográfica. Métodos: Estudo transversal com dados relativos aos medicamentos comparticipados e dispensados nas farmácias comunitárias de Portugal Continental em 2019, aos utentes com mais de 65 anos. Efetuou-se análise descritiva demográfica e geográfica, por denominação comum internacional e grupo terapêutico. A utilização foi estudada através do número de embalagens comparticipadas dispensadas e número de embalagens comparticipadas dispensadas per capita (dados do Instituto Nacional de Estatística). Resultados: Observou-se uma dispensa superior nas mulheres, a qual foi aumentando com a idade, à exceção dos idosos 85+, nos quais a diferença tendeu a diminuir. No que diz respeito ao número de embalagens comparticipadas dispensadas per capita, a tendência foi inversa, com os homens muito idosos a ultrapassarem as mulheres 85+ (média de embalagens: 55,5 nos homens versus 55,1 nas mulheres). Nas mulheres, os medicamentos mais consumidos foram os do foro cardiovascular (31%), seguidos dos prescritos para o sistema nervoso central (30%) e antidiabéticos (13%). Nos homens, o ranking foi liderado também pelos medicamentos para o aparelho cardiovascular (37%); contudo, em segundo lugar surgem os antidiabéticos (16%), seguidos dos medicamentos para a hiperplasia benigna da próstata (14%). Conclusão: Existiram diferenças de sexo e idade relevantes no padrão de dispensa de medicamentos comparticipados nos idosos portugueses em 2019. Esta é a primeira análise publicada de âmbito nacional à dispensa de medicamentos em idosos, sendo essencial para caracterizar o perfil de utilização de medicamentos pelos seniores em Portugal.


Assuntos
Pacientes Ambulatoriais , Polimedicação , Idoso de 80 Anos ou mais , Humanos , Idoso , Masculino , Feminino , Adolescente , Estudos Transversais , Portugal/epidemiologia , Prevalência , Hipoglicemiantes
16.
J Trace Elem Med Biol ; 78: 127164, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37031660

RESUMO

BACKGROUND: Brazil has consolidated a relevant position in the world market, being the largest exporter and second producer of beef. Genetics, feeding system, geographic origin and climate influence the multielement profile of beef. The feasibility of combining classification algorithms with major and trace elements was evaluated as a tool for authentication of beef cuts. METHODS: Animals of Angus, Nelore and Wagyu crossbreeds, raised in a vertically integrated system, were sampled at the slaughterhouse for chuck steak, rump cap and sirloin steak. Supervised learning algorithms i.e. Classification and Regression Tree (CART), Multilayer Perceptron (MLP), Naïve Bayes (NB), Random Forest (RF) and Sequential Minimal Optimization (SMO) were used to build classification models based on the multielement profile of beef determined by neutron activation analysis. RESULTS: Br, Co, Cs, Fe, K, Na, Rb, Se and Zn were determined in the beef samples. The classification accuracy values obtained for the beef cuts were 96% (MLP), 95% (SMO), 91% (RF), 86% (NB) and 70% (CART). CONCLUSION: The Multilayer Perceptron algorithm provided the best classification performance towards authentication of beef cuts on basis of major and trace element mass fractions.


Assuntos
Algoritmos , Aprendizado de Máquina , Animais , Bovinos , Teorema de Bayes , Algoritmo Florestas Aleatórias , Brasil
17.
Micromachines (Basel) ; 13(10)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36296077

RESUMO

We present a microfluidic chip for protein labeling in the human serum-based matrix. Serum is a complex sample matrix that contains a variety of proteins, and a matrix is used in many clinical tests. In this study, the device performance was tested using commercial serum samples from healthy donors spiked with the following target proteins: cellular fibronectin (c-Fn) and matrix metallopeptidase 9 (MMP9). The microfluidic molds were fabricated using micro milling on acrylic and using stereolithography (SLA) three-dimensional (3D) printing for an alternative method and comparison. A simple quality control was performed for both fabrication mold methods to inspect the channel height of the chip that plays a critical role in the labeling process. The fabricated microfluidic chip shows a good reproducibility and repeatability of the performance for the optimized channel height of 150 µm. The spiked proteins of c-Fn and MMP9 in the human serum-based matrix, were successfully labeled by the functionalized magnetic nanoparticles (MNPs). The biomarker labeling occurring in the serum was compared using a simple matrix sample: phosphate buffer. The measured signals obtained by using a magnetoresistive (MR) biochip platform showed that the labeling using the proposed microfluidic chip is in good agreement for both matrixes, i.e., the analytical performance (sensitivity) obtained with the serum, near the relevant cutoff values, is within the uncertainty of the measurements obtained with a simple and more controlled matrix: phosphate buffer. This finding is promising for stroke patient stratification where these biomarkers are found at high concentrations in the serum.

18.
Biosens Bioelectron ; 210: 114302, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35487137

RESUMO

The recent worldwide spread of viral infections has highlighted the need for accurate, fast, and inexpensive disease diagnosis and monitorization methods. Current diagnostics tend to focus either on molecular or serological testing. In this work we propose a dual detection assay approach for viral diseases, where both serological and molecular assays are combined in a single analysis performed on a magnetoresistive system. This type of assay guarantees an accurate assessment of the infection phase, saving time and costs associated with multiple independent tests. Zika and dengue viruses were used as model diseases for the validation of the system. Human IgG anti-zika and anti-dengue antibodies were successfully detected in infected patients' serum, using a novel approach combining competitive and sandwich strategies in a magnetoresistive portable platform. Specificity and sensitivity values of 100% were obtained. Calibration curves with dynamic ranges between 10 ng/mL and 1 µg/mL were established achieving LODs of 1.26 and 1.38 nM for IgG anti-ZIKV and anti-DENV antibodies, respectively. Viral RNA detection down to a few hundreds of pM was also successfully carried out after the design of specific oligo probes and primers for RT-PCR amplification. Dual assays were performed for both viruses, where viral RNA and anti-virus antibodies in serum samples were simultaneously detected. The results obtained for the detection of the molecular and serological targets in the dual assay format show no significant difference between the ones obtained individually, proving the feasibility and accuracy of the dual detection assay. This assay format represents a new paradigm in viral infections diagnostics.


Assuntos
Técnicas Biossensoriais , Vírus da Dengue , Dengue , Infecção por Zika virus , Zika virus , Anticorpos Antivirais , Vírus da Dengue/genética , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imunoglobulina G , RNA Viral , Sensibilidade e Especificidade , Zika virus/genética , Infecção por Zika virus/diagnóstico
19.
J Comp Neurol ; 530(18): 3270-3287, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36094014

RESUMO

Our knowledge about the detailed wiring of neuronal circuits in the spinal dorsal horn (DH), where initial sensory processing takes place, is still very sparse. While a substantial amount of data is available on the somatodendritic morphology of DH neurons, the laminar and segmental distribution patterns and consequential function of individual axons are much less characterized. In the present study, we fully reconstructed the axonal and dendritic processes of 10 projection neurons (PNs) and 15 interneurons (INs) in lamina I of the rat, to reveal quantitative differences in their distribution. We also performed whole-cell patch-clamp recordings to test the predicted function of certain axon collaterals. In line with our earlier qualitative description, we found that lamina I INs in the lateral aspect of the superficial DH send axon collaterals toward the medial part and occupy mostly laminae I-III, providing anatomical basis for a lateromedial flow of information within the DH. Local axon collaterals of PNs were more extensively distributed including dorsal commissural axon collaterals that might refer to those reported earlier linking the lateral aspect of the left and right DHs. PN collaterals dominated the dorsolateral funiculus and laminae IV-VI, suggesting propriospinal and ventral connections. Indeed, patch-clamp recordings confirmed the existence of a dorsoventral excitatory drive upon activation of neurokinin-1 receptors that, although being expressed in various lamina I neurons, are specifically enriched in PNs. In summary, lamina I PNs and INs have almost identical dendritic input fields, while their segmental axon collateral distribution patterns are distinct. INs, whose somata reside in lamina I, establish local connections, may show asymmetry, and contribute to bridging the medial and lateral halves of the DH. PNs, on the other hand, preferably relay their integrated dendritic input to deeper laminae of the spinal gray matter where it might be linked to other ascending pathways or the premotor network, resulting in a putative direct contribution to the nociceptive withdrawal reflex.


Assuntos
Receptores da Neurocinina-1 , Medula Espinal , Ratos , Animais , Axônios/fisiologia , Interneurônios , Células do Corno Posterior , Neurônios/fisiologia , Análise Espacial , Percepção
20.
Pain ; 163(2): 362-375, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33990106

RESUMO

ABSTRACT: Afferents from the C2 spinal nerve (SN) and trigeminal nerve (TN) innervate neighboring cranial territories, and their convergence on the upper cervical dorsal horn neurons represents neural substrate of pain referral in primary headache disorders. Unfortunately, little is known about trigeminocervical input to the major spinal nociceptive projection area lamina I. Here, we used ex vivo brainstem-cervical cord preparation for the visually guided whole-cell recording from the upper cervical lamina I neurons. We show that 50% of them receive convergent monosynaptic input from both nerves, whereas 35% and 11% of neurons receive specific supply from the C2 SN and TN, respectively. Altogether, 10 distinct patterns of synaptic input from the C2 SN and TN to lamina I neurons could be identified. Although stimulation of both nerves evoked excitatory/inhibitory responses, more numerous pure inhibitory inputs arose from the TN. We show that cervical and trigeminal nociceptors converge on to lamina I projection and inhibitory neurons. Thus, trigeminocervical input in lamina I is processed in both nerve-specific and convergent circuitries. Afferent convergence on to inhibitory interneurons serves as a feedforward mechanism balancing excitatory drive to projection neurons. Disruption of this balance may cause pain in primary headache syndromes.


Assuntos
Neurônios Aferentes , Nociceptividade , Vias Aferentes/fisiologia , Neurônios , Neurônios Aferentes/fisiologia , Nociceptores/fisiologia , Corno Dorsal da Medula Espinal/fisiologia
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