Browsing by Author "Sousa, A."
Now showing 1 - 10 of 15
Results Per Page
Sort Options
- Assessing risk factors for migraine: differences in gender transmissionPublication . Lemos, C.; Alonso, I.; Barros, J.; Sequeiros, J.; Pereira-Monteiro, J.; Mendonça, D.; Sousa, A.Abstract AIM: Our aim was to assess which specific factors are contributing to an increased risk of migraine in a group of 131 Portuguese families. METHODS: We studied 319 first-degree relatives, using a multilevel approach to account for the dependency among members from the same family. We included in the model relative's gender, the proband's gender and age-at-onset, to evaluate if any of these variables were associated with relative's affection status. We also included in the model proband's migraine subtype. We further assessed female and male transmissions within the proband nuclear family. RESULTS: Relatives' gender was found to be a risk factor for migraine (Odds Ratio = 2.86; 95% CI = 1.75-4.67), with females at a higher risk. When splitting probands according to their migraine subtype, we found that none of the variables studied contributed to relatives of MA-probands affection-status. Our results also show a significant difference between proband's transmission and the gender of the parents and offspring. CONCLUSIONS: With this study, we showed that gender is truly a risk factor for migraine and that a gender-biased transmission is also observed. This reinforce the importance of identifying genes associated with migraine that are modulated by genes located in the sex chromosomes and the study of mitochondrial DNA or X-chromosome and hormonal-related effects associated with migraine susceptibility
- Avaliação auditiva de comunidades escolares portuguesas: Audiologia Escolar versus Rastreio AuditivoPublication . Lopes, P.; Tomé, D.; Sousa, A.; Magalhães, A.Objectivo: Estudo da incidência da perda auditiva e de problemas otológicos em comunidades escolares do Norte do país de um total de 2550 participantes, entre os 3 e os 17 anos de idade. Desenho do Estudo: Levantamento estatístico nas próprias instituições de ensino sendo realizado um protocolo de avaliação auditiva de rastreio. Material e Métodos: A todos os participantes foi realizado o mesmo protocolo de avaliação que consistiu numa anamnese audiológica, otoscopia e exame audiométrico de rastreio, sendo considerado como critério de inclusão a autorização prévia por parte do encarregado de educação. Resultados: Foram identificados diversos problemas otológicos e a audiometria tonal de rastreio contabilizou limiares auditivos indicativos de hipoacusia, uni e bilateralmente, em cerca de 5,7% dos casos. Conclusões: O rastreio auditivo deve ser realizado o mais precocemente possível e fazer parte integral dos cuidados de saúde primários, de modo a orientar a criança para uma educação e acompanhamento apropriados.
- BDNF and CGRP interaction: implications in migraine susceptibilityPublication . Lemos, C.; Mendonça, D.; Pereira-Monteiro, J.; Barros, J.; Sequeiros, J.; Alonso, I.; Sousa, A.Abstract OBJECTIVES: Migraine pathophysiology involves several pathways. Our aims were to explore a possible role of the brain-derived neurotrophic factor gene (BDNF) in migraine susceptibility; to study, for the first time, the calcitonin gene-related peptide gene (CGRP); and a possible interaction between the two. METHODS: Using a case-control approach, four tagging single nucleotide polymorphisms (SNPs) (rs7124442, rs6265, rs11030107, and rs2049046) of BDNF and one tagging SNP-rs1553005-of CGRP were analyzed in 188 cases and 287 controls. A multivariable logistic regression was performed, adjusting for gender. Allelic and haplotypic frequencies were estimated. Interaction was assessed by a stepwise multivariable-logistic regression and confirmed by a multifactor dimensionality reduction analysis. RESULTS: No significant main effects were found; however, a significant interaction was found between BDNF and CGRP, showing an increased risk for the AT-genotype of rs2049046 and the GC-genotype of rs1553005 (odds ratio=1.88, 95% confidence interval: 1.20-2.93) for migraineurs. CONCLUSION: Our data support the hypothesis of an interaction between BDNF and CGRP in migraine susceptibility that should be further explored.
- Economic Impact of Prosthetic Joint Infection - an Evaluation Within the Portuguese National Health SystemPublication . Sousa, A.; Carvalho, A.; Pereira, C.; Reis, E.; Santos, A.; Abreu, M.; Soares, D.; Fragoso, R.; Ferreira, S.; Reis, M.; Sousa, R.Introduction: Prosthetic infection is a devastating complication of arthroplasty and carries significant economic burden. The objective of this study was to analyze the economic impact of prosthetic hip and knee infection in Portuguese National Health System. Material and Methods: Case-control study carried out from January 2014 to December 2015. The mean costs of primary arthroplasties and prosthetic revision surgeries for non-infectious reasons were compared with the costs of prosthetic infections treated with debridement and preservation of the prosthesis or with two-stage exchange arthroplasty.The reimbursement for these cases was also evaluated and compared with its real costs. Results: A total of 715 primary arthroplasties, 35 aseptic revisions, 16 surgical debridements and 15 revisions for infectious reasons were evaluated. The cost of primary arthroplasties was 3,230€ in the hips and 3,618€ in the knees. The cost of aseptic revision was 6,089€ in the hips and 7,985€ in the knees. In the cases treated with debridement and implant retention the cost was 5,528€ in the hips and 4,009€ in the knees. In cases of infections treated with a two-stage revision the cost was 11,415€ and 13,793€ for hips and knees, respectively. Conclusion: As far as we know this is the first study that analyzes the economic impact of prosthetic infection in the Portuguese context. Although direct compensation for treating infected cases is much lower than calculated costs, infected cases push the overall hospital case-mix-index upwards thus increasing financial compensation for the entire cohort of treated patients. This knowledge will allow for more informed decisions about health policies in the future.
- Evidence of syntaxin 1A involvement in migraine susceptibility: a Portuguese study.Publication . Lemos, C.; Pereira-Monteiro, J.; Mendonça, D.; Ramos, E.; Barros, J.; Sequeiros, J.; Alonso, I.; Sousa, A.Abstract OBJECTIVE: To confirm syntaxin 1A as a risk factor for migraine, given that syntaxin 1A interacts with several factors in migraine pathophysiology. DESIGN: Case-control approach. SETTING: An outpatient clinic. PARTICIPANTS: In a sample of 188 migraineurs (111 without aura and 77 with aura) and 287 migraine-free controls, 3 tagging SNPs of STX1A (rs3793243, rs941298, and rs6951030) were analyzed. A backward stepwise multiple logistic regression was performed. Allelic and haplotypic frequencies were compared between cases and controls. RESULTS: We found that rs941298 and rs6951030 were risk factors for migraines. In particular, the TT genotype of rs941298 is associated with an increased risk of both migraine in general and migraine without aura; the GG and GT genotypes for rs6951030 are also associated with migraine, while the GT genotype of rs6951030 was found to be significant in the migraine without aura group. The single-nucleotide polymorphism rs3793243 did not show any significant association. In the haplotype-based analysis, we found an underrepresentation of the T-C-T haplotype (rs3793243-rs941298-rs6951030) in the global sample and in migraine without aura group. We found an enrichment of the G allele of rs6951030 for female migraineurs only. CONCLUSIONS: We confirmed the involvement of syntaxin 1A in migraine susceptibility regarding rs941298. In addition, we found rs6951030 to also be associated in Portuguese migraine patients. Sex differences should be further explored to disentangle a possible sex susceptibility in syntaxin 1A
- Familial amyloid polyneuropathy in Portugal: New genes modulating age-at-onsetPublication . Santos, D.; Coelho, T.; Alves-Ferreira, M.; Sequeiros, J.; Mendonça, D.; Alonso, I.; Lemos, C.; Sousa, A.OBJECTIVES: Familial amyloid polyneuropathy (FAP ATTRV30M) shows a wide variation in age-at-onset (AO) between clusters, families, and among generations. We will now explore some candidate genes involved in altered disease pathways in order to assess their role as genetic modifiers of AO, using a family-centered approach. METHODS: We analyzed 62 tagging SNPs from nine genes-NGAL,MMP-9,BGN,MEK1,MEK2,ERK1,ERK2,HSP27, and YWHAZ - in a sample of 318 V30M Portuguese patients (106 families), currently under follow-up. A generalized estimating equation analysis was used to take into account nonindependency of AO between relatives. Also, an in silico analysis was performed in order to assess the functional impact of significant variants associated with AO. RESULTS: We found for the first time variants from six genes (NGAL,BGN (in the female group), MEK1,MEK2,HSP27, and YWHAZ) that were significantly associated with early- and/or late-onset. Then, we confirmed a strong synergistic interaction between NGAL and MMP-9 genes. Additionally, by an in silico analysis, we found some variants for MEK1 gene that may alter binding of the transcription factors and that influence the regulation of gene expression regarding microRNA binding sites and splicing regulatory factors. INTERPRETATION: These findings showed that different genetic factors can modulate differently the onset of disease's symptoms and revealed new mechanisms with clinical implications in the genetic counseling and follow-up of mutation carriers and could contribute for development of potential therapeutical targets.
- Familial ATTR amyloidosis: microalbuminuria as a predictor of symptomatic disease and clinical nephropathyPublication . Lobato, L.; Beirao, I.; Silva, M.; Bravo, F.; Silvestre, F.; Guimaraes, S.; Sousa, A.; Noel, LH.; Sequeiros, J.Familial ATTR amyloidosis: microalbuminuria as a predictor of symptomatic disease and clinical nephropathy. Lobato L, Beirão I, Silva M, Bravo F, Silvestre F, Guimarães S, Sousa A, Noël LH, Sequeiros J. SourceDepartment of Nephrology and Centro de Estudos de Paramiloidose, Hospital Geral de Santo António and Institute for Molecular and Cell Biology, Porto, Portugal. llobato@netcabo.pt Abstract BACKGROUND: Portuguese type familial amyloid polyneuropathy (FAP) is a neuropathic amyloidosis caused by a mutant transthyretin (TTR). Varying degrees of renal involvement have been reported. Our aim was to assess the value of microalbuminuria (MA) for predicting clinical neurological disease and overt nephropathy in TTR-related amyloidosis. METHODS: All subjects had the TTR Val30Met mutation, and were recruited between 1993 and 1999. We have prospectively evaluated 22 asymptomatic gene carriers (7 male, 15 female; mean age 41.6+/-9.6 years) and 32 patients with neuropathy (14 male, 18 female; 36.8+/-8.8 years, on average, 33.0+/-9.3 years at the onset of neuropathy). We measured urinary albumin excretion every year, if asymptomatic, or every 6 months if already affected. Kidney biopsies were performed in patients with normal urinary albumin excretion, MA, and overt nephropathy, respectively. RESULTS: In asymptomatic carriers, persistent MA was detected in eight (36%) subjects. The presence of MA in asymptomatic gene carriers, compared with those having normal urinary albumin excretion, conferred a 4.8-fold risk of developing neuropathy, usually within the subsequent 3 years. Once neurological signs appeared, nephropathy, manifested as MA, progressed to overt nephropathy in one-half of subjects. In patients with neuropathy, 24 (75%) had MA during follow-up: evolution towards clinical renal disease occurred in 14 (58%) and renal failure occurred in five (21%), always after a course of MA. Proteinuria or renal failure without prior persistent MA were never observed in the present patient cohort. Histopathological evaluation did not reveal glomerular lesions other than amyloid deposits to explain abnormal urinary albumin excretion. The amount of mesangial and vascular-pole amyloid deposits was correlated with the degree of albuminuria. CONCLUSIONS: Microalbuminuria represents the first stage of clinical TTR amyloid nephropathy and is premonitory of neuropathy. Its presence identifies a subgroup of patients who are more prone to develop overt nephropathy. Screening of MA may be important to assess disease onset and to recommend liver transplantation in individuals at risk.
- Familial clustering of migraine: further evidence from a Portuguese studyPublication . Lemos, C.; Castro, M.; Barros, J.; Sequeiros, J.; Pereira-Monteiro, J.; Mendonça, D.; Sousa, A.Abstract OBJECTIVE: Our aim was to evaluate familial aggregation of migraine in a large group of Portuguese families, and to assess if familial aggregation differs between MA and MO. METHODS: Familial aggregation was evaluated by estimating relative risk (RR) of migraine in 143 first-degree relatives of 50 probands with MA, in 196 first-degree relatives of 94 probands with MO and also in proband's spouses. Probands were enrolled in the study from a clinical sample and a population sample was used as reference. RESULTS: A significantly increased risk of migraine was found in both first-degree relatives of MO probands (RR = 3.7; 95% CI: 3.2-4.3) and of MA probands (RR = 3.6; 95% CI: 3.1-4.3), comparatively to the general population. Risk for spouses was not increased. First-degree relatives of MA probands and MO probands had a significantly increased risk of both MA and MO compared to the general population. In the group of MA probands, RR of MA in first-degree relatives reached a significant 4-fold increase when compared with RR of MO (RR(MA|MA) = 12.2, 95%CI: 7.7-19.5; RR(MO|MA) = 3.1, 95%CI: 2.5-3.8), while, in the group of MO probands, RR of MA was not significantly increased when compared with RR of MO (RR(MA|MO) = 5.3, 95%CI: 3.1-9.2; RR(MO|MO) = 4.0, 95%CI: 3.5-4.7). CONCLUSIONS: The present study focus on familial aggregation of migraine in a Portuguese population. Our results demonstrate a substantial familial risk of migraine with evidence of both common and specific etiologic mechanisms for either migraine subtypes.
- [Infection due to Mycoplasma pneumoniae: three cases with neurological complications].Publication . Cunha, J.; Madalena, C.; Guimarães, P.; Sousa, A.; Temudo, T.Summary. Introduction. Mycoplasma pneumoniae infection has been associated with severe central nervous system diseases. The pathogenesis of these disorders is unknown and the treatment uncertain. Case reports. The authors present three cases of central nervous system diseases: acute transverse myelitis, cerebellitis and encephalomyelitis associated with M. pneumoniae infection. Conclusions. M. pneumoniae infection should be considered in all cases of severe acute central nervous system symptomatology. El Mycoplasma pneumoniae es un agente implicado frecuentemente en infecciones respiratorias de niños y adultos [1,2]. Se pueden producir complicaciones extrarrespiratorias básicamente mucocutáneas (eritema multiforme, eritema nudoso, síndrome de StevenJohnson), cardíacas (miocarditis, pericarditis), articulares (artritis), hematológicas (anemia hemolítica, trombocitopenia, coagulación vascular diseminada), pancreatitis, salpingitis y complicaciones neurológicas [13]. La implicación del sistema nervioso central (SNC) se estima en aproximadamente un 0,1% del total de infecciones producidas por M. pneumoniae, y puede afectar al 7% de los pacientes hospitalizados a causa de una infección producida por este agente [2,3]. Las complicaciones neurológicas incluyen: encefalitis, meningoencefalitis, encefalomielitis, polirradiculoneuropatía (como el síndrome de GuillainBarré), cerebelitis, psicosis, mielitis transversa y coma [14]. Presentamos tres casos clínicos con complicaciones neurológicas en el contexto de una infección por M. pneumoniae (mielitis transversa, cerebelitis, encefalomielitis), cuyo diagnóstico se estableció a partir de los análisis clínicos y los exámenes auxiliares de diagnóstico efectuados, principalmente las serologías seriadas. A infecção por Mycoplasma pneumoniae tem sido associada a múltiplas complicações neurológicas. A patogénese destas permanece incerta e o seu tratamento controverso. Casos clínicos. Os autores apresentam três casos de complicação neurológica em contexto de infecção pelo M. pneumoniae: mielite transversa, cerebelite e encefalomielite. Conclusão. A infecção por M. pneumoniae deve ser considerada em todos os casos de sintomatologia severa aguda do sistema nervoso central
- Pneumocephalus Following Unidentified Dural Puncture: A Case Report with an Unusual Neurological PresentationPublication . Figueira, H.; Guimaraes, J.; Sousa, A.; Regalado, A.Pneumocephalus is a rare consequence of epidural anesthesia, which may occur following inadvertent or unidentified dural puncture when the loss of resistance to air technique is applied to identify the epidural space. Headache is the most common symptom presented in this condition, usually with sudden onset. This case report describes an unusual presentation of diffuse pneumocephalus after an unidentified dural puncture. The patient (male, 67 years old) was submitted to epidural catheter placement for the treatment of acute exacerbation of ischemic chronic pain using loss of resistance to air technique. No cerebrospinal fluid or blood flashback was observed after needle withdrawal. Shortly after the intervention, the patient presented symptoms of lethargy, apathy, and hypophonia, which are not commonly associated with pneumocephalus. No motor or sensory deficits were detected. Cranial computed tomography showed air in the frontal horn of the left ventricle, subarachnoid space at interhemispheric fissure and basal cisterns, confirming the diagnosis of diffuse pneumocephalus. The patient remained under vigilance with oxygen therapy and the epidural catheter left in place. After 24 hours, cranial computed tomography showed air in the temporal and frontal horns of the left ventricle, with no air in the subarachnoid space. The patient presented no neurological signs or symptoms at this time. Although headache is the most common symptom presented in reported cases of pneumocephalus, this case shows the need for the clinician to be aware of other signs and symptoms that may be indicative of this condition, in order to properly diagnose and treat these patients.