The epidemiology of multiple sclerosis in the entre Douro e Vouga region of northern Portugal: a multisource population-based study.

BACKGROUND: The prevalence of Multiple Sclerosis (MS) has been increasing worldwide and the north-south gradient of prevalence may be disappearing in the Northern hemisphere. The few previous prevalence studies performed in Portugal have reported a lower prevalence than the average for Western Europe. The aim of this study is to estimate the prevalence of MS in the Entre Douro e Vouga region, in Northern Portugal. METHODS: Multiple overlapping sources were used to ascertain all cases from the reference population: records from hospitals in the region and neighbouring regions; diagnostic databases of primary care physicians; and applications for disability benefits. The prevalence date was set at 1 January 2014. The reference population was 274,859 inhabitants. Patients' neurologists were contacted to retrieve clinical information and confirm the diagnosis based. RESULTS: A total of 177 patients were identified after eliminating duplicates from different sources. The female to male ratio was 1.9 and the mean age at disease onset was 33.5 (standard deviation: 10.3). Clinically isolated syndrome accounted for 9.0% of patients, relapsing remitting for 58.8%, secondary progressive for 20.3% and primary progressive for 11.8%. The prevalence was estimated in 64.4 patients per 100,000 (95% confidence interval: 54.9;73.9). CONCLUSIONS: In this study we report a higher point prevalence of MS than had been previously described in Portugal, but still far from the higher values recently reported in other Southern European countries.

Utilization of phage display to identify antigenic regions in the PCV2 capsid protein for the evaluation of serological responses in mice and pigs.

Porcine circovirus 2 (PCV2) is associated with a series of swine diseases. There is a great interest in improving our understanding of the immunology of PCV2, especially the properties of the viral capsid protein Cap-PCV2 and how they relate to the immunogenicity of the virus and the subsequent development of vaccines. Phage display screening has been widely used to study binding affinities for target proteins. The aim of this study was to use phage display screening to identify antigenic peptides in the PCV2 capsid protein. After the selection of peptides, five of them presented similarity to sequences found in cap-PCV2, and four peptides were synthesized and used for immunization in mice: 51-CTFGYTIKRTVT-62 (PS14), 127-CDNFVTKATALTY-138 (PS34), 164-CKPVLDSTIDY-173 (PC12), and 79-CFLPPGGGSNT-88 (PF1). Inoculation with the PC12 peptide led to the highest production of antibodies. Furthermore, we used the PC12 peptide as an antigen to examine the humoral response of swine serum by ELISA. The sensitivity and specificity of this assay was 88.9% and 92.85%, respectively. Altogether, characterization of immunogenic epitopes in the capsid protein of PCV2 may contribute to the improvement of vaccines and diagnostics.

Ischemic vagus nuclei lesions and hyperglycemia: a study in 26 patients with lateral medullary infarction and matched controls.

BACKGROUND: Hyperglycemia is common after stroke in diabetic and nondiabetic patients. Furthermore, it has been associated with infarct expansion, worse functional outcomes and higher mortality. In a previous study, infarction of the insular region was related to higher poststroke glucose levels than infarcts in other cortical areas. Experimental studies in animal models suggested that the lower brainstem nuclei of the vagus nerve modulate insulin secretion. These nuclei are usually affected in lateral medullary infarction (LMI). We evaluated whether patients with lateral medullary stroke have worse poststroke glycemic control than other stroke patients. METHODS: A hospital-based stroke registry was used to identify 26 patients from the years 2000 to 2010 who fulfilled the following inclusion criteria: (1) a first-ever stroke; (2) neurological deficits compatible with LMI; (3) MRI confirmation of an ischemic lesion of the lateral medulla involving the vagus nerve nuclei, and (4) no simultaneous infarcts. Patients were excluded if they were admitted to the hospital more than 24 h after stroke onset or died in the first 24 h after hospital admission. A control group of other stroke patients was randomly selected from the same stroke registry and over the same time period, matching for the age and gender of the LMI group. The average glycemia was compared between the two groups using a linear regression model adjusted for confounders. Glycated hemoglobin at admission was used to estimate prestroke glycemic control. Prestroke glycemic averages were then compared with poststroke glycemia for the two groups using the Wilcoxon signed test for related samples. RESULTS: The average glycemia of the LMI patients in the first 24 h after stroke was 9.4 mmol/l (SD 3.2), and from 24 to 72 h it was 7.6 mmol/l (SD 2.8). In the comparison group, these values were 7.7 (SD 2.8) and 7.1 mmol/l (SD 2.7), respectively. As expected, diabetic patients had a significantly higher glycemia than nondiabetic patients (p < 0.0001). The adjusted linear regression model showed the average glycemia differences to be significant for the first 24 h (p = 0.001; R(2) = 55.6%) but not for the 24- 72 h period. The frequency of previous diabetes mellitus was similar in both groups. As compared to prestroke glycemic estimates, glycemia in lateral medullary stroke patients increased significantly more than in controls during the first 24 h after stroke (p = 0.01), but again there were no significant differences for the 24-72 h period. CONCLUSIONS: This study suggests that ischemic lesions of the vagus nerve nuclei are associated with worse early poststroke glycemic control than stroke in other locations. Confirmation of this hypothesis and the long-term implications of glucose control impairment warrant further prospective studies.

Superficial siderosis and anticoagulation therapy: different presentations, different outcomes.

Superficial siderosis is a potentially manageable neurodegenerative disorder, caused by chronic subarachnoid haemorrhage and iron deposition along the central nervous system surfaces. Association with oral anticoagulant therapy is well known, but its definite role as a causative agent is yet to be clarified. Two Caucasian women, both under long-term oral anticoagulation: a 74 year old woman with slowly progressive hearing loss and mild cerebellar ataxia; a 72 year old woman suffering from behavioural changes, rapidly progressive cognitive decline and latter developing paraparesis. Magnetic resonance imaging showed striking hypointensities along the surfaces of cerebellum, brainstem, frontotemporal cortices, spinal cord, and lumbar arachnoid therefore suggesting superficial siderosis. No specific bleeding source was found in any of the patients. Anticoagulation could not be stopped in the first patient due to a mechanic valve and slowly progressive worsening occurred. In contrast, for the second patient anticoagulation withdrawal was feasible and marked motor and cognitive improvement ensued. Superficial siderosis is associated with unvarying progression, mostly when no direct source of bleeding is identified. Nonetheless, we verified striking motor and cognitive improvement after anticoagulants withdrawal in one of the patients. This may reinforce the need to consider such modifiable factor in future patient management.

Polimorfismo do 16S mtDNA por LIS-SSCP em Melipona scutellaris Latreille, 1811 (Hymenoptera, Apidae, Meliponini) / Polymorphism of the 16S mtDNA for LIS-SSCP in Melipona scutellaris Latreille, 1811 (Hymenoptera, Apidae, Meliponini)

A técnica de Low Ionic Strength Single-Strand Conformation Polymorphism (LIS-SSCP) foi desenvolvida, como forma de detectar mutação em fita simples de DNA. Esta técnica consiste basicamente na separação de fragmentos de DNA de fita simples por desnaturação, por meio de uma solução de baixa força iônica (LIS) a base de sacarose. Utilizou-se a técnica de LIS-SSCP para estudar populações de Melipona scutellaris Latreille, 1811 quanto à presença de variações do 16S mtDNA. Estas populações foram introduzidas no Meliponário Uberlândia, Uberlândia-MG, em diferentes período de tempo, colônias K (introduzidas em 1987) e colônias AB e N (introduzidas em 1999 e 2000 respectivamente). Os resultados não mostraram variações no 16S mtDNA entre as colônias K e colônias AB e N, embora houvesse nítidas diferenças morfológicas e comportamentais entre elas.

The Single Strand Conformation Polymorphim (SSCP) is a technique that was developed to detect mutations in single strande DNAs. This technique consistes in separating the single strand DNA fragments by their desnaturation using a low ionic stregth (LIS) solution which is composed of sucrose. We use the LIS-SSCP technique with the purpose to study populations of Melipona scutellaris Latreille, 1811, about the presence of 16SmtDNA variations. The populations were introduced in the Uberlândia Meliponary (Uberlândia-MG, Brazil) in different periods of time, colonies K (introduced in 1987) and colonies AB and N (introduced in 1999 and 2000 respectively). The results had not shown variations between the colonies K, AB and N, although in had clear morphologic and behavioral difference between these colonies.