Macrovascular contribution in activation patterns of working memory.

Brain activation maps of blood oxygenation level dependent (BOLD) signals during functional magnetic resonance imaging (fMRI) are sensitive to unwanted contributions from large vessels. Most BOLD-fMRI studies are based on a stimulus-correlated modulation of the MRI signal amplitude that is sensitive to desired microvascular effects and unwanted macrovascular effects. Aiming to suppress macrovascular effects in activation patterns, this BOLD-fMRI study evaluates brain activation during a verbal working memory task (2-back) in healthy volunteers (n=18) using the amplitude and phase components of the MRI signal. The use of the first time point as a phase reference allowed us to eliminate phase wrapping artifacts and increase the statistical power of 'phase' activation, and this information was used to filter out voxels with significant macrovascular (i.e., draining and pial veins) contribution in 'amplitude' activation patterns. Across subjects, the task produced large modulations of the relative phase in the occipital, dorsolateral prefrontal, and parietal cortices, suggesting a common distribution of draining veins in these regions across subjects, and in the rostral frontal cortex, probably associated to stimulus-correlated motion of the head. The phase filtering method partially suppressed BOLD responses in the superior and lateral prefrontal, parietal, and occipital cortices; therefore the commonly reported brain activation in these cortices during working memory tasks may include significant macrovascular contributions. This study suggests that the phase information embedded in the MRI signal can be used to suppress unwanted macrovascular contributions in fMRI studies.     

Immunopathology of bullous pemphigoid. Basement membrane deposition of IgE, alternate pathway components and fibrin

Sixteen patients with bullous pemphigoid were examined using direct and indirect immunofluorescent techniques with antisera specific for C1q, C4, C3, C5, C3 proactivator, properdin, fibrinogen, IgA, IgM, IgG and IgE. The results of these studies are consistent with the activation of complement via the classical (antibody–C1q) sequence as well as via the alternate pathway. Fibrinogen and/or fibrin derivatives were demonstrated on the basement membrane of ten of fifteen patients tested and IgE basement membrane staining was found in four individuals.     

Familial arrhythmogenic dysplasia of the right ventricle. Observation of 3 cases

A family with "arrhythmogenic right ventricular dysplasia (ARVD)" is described. ARVD is pathologically characterised by a partial or total degeneration of the right ventricular myocardium, replaced by fatty and fibrous tissue. This causes dangerous ventricular arrhythmias or congestive heart failure in infancy. About the three described patients, a sixteen-year-old subject died suddenly, and his anatomical and histopathological reports have been presented. Familiarity, rarely treated in literature, and the presence, in the died subject, of a damage of the left ventricle too, are the peculiar characteristic of these "ARVD" cases. The importance about instrumental non-invasive studies has been underlined in order to know early "ARVD", which can be deceptive clinically. The authors suppose there is surely, at the beginning of "dysplasia", a genetic alteration of the right cardiac musculature, but acquired noxae could insert afterwards, on this genetic basis.     

Socioeconomic situation and living conditions: comparison of two population-based cohorts from southern Brazil

Socioeconomic and family characteristics of two cohorts of babies born in 1982 and 1993 in Pelotas (Southern Brazil) were compared. There were 6,011 births in 1982 and 5,304 in 1993. In relation to family income, there were fewer poor babies in 1993; 60.8 % of the families earned less than 3 times the monthly minimum wage in 1993, as compared to 69.5% in 1982. Sanitary conditions also improved over the decade, and the proportion of families with running water and flush toilets increased by 10%. On the other hand, there were no changes in the proportion of single-parent families or availability of home appliances like radios, stoves, and refrigerators. The mean number of persons per household increased from 3.0 in 1982 to 3.2 in 1993. In general, comparison of the two birth cohorts in this city suggests an improvement in quality of living over the time period for families with newborns. This finding should be taken into account when studying the evolution of health indicators over the course of the decade.     

Influence of different hemodialysis membranes on red blood cell susceptibility to oxidative stress

Oxidative stress is crucial in red blood cell (RBC) damage induced by activated neutrophils in in vitro experiments. The aim of the study was to evaluate whether the bioincompatibility phenomena occurring during hemodialysis (HD) (where neutrophil activation with increased free radical production is well documented) may have detrimental effects on RBC. We evaluated RBC susceptibility to oxidative stress before and after HD in 15 patients using Cuprophan, cellulose triacetate, and polysulfone membrane. RBC were incubated with t-butyl hydroperoxide as an oxidizing agent both in the presence and in the absence of the catalase inhibitor sodium azide. The level of malonaldehyde (MDA), a product of lipid peroxidation, was measured at 0, 5, 10, 15, and 30 min of incubation. When Cuprophan membrane was used, the MDA production was significantly higher after HD, indicating an increased susceptibility to oxidative stress in comparison to pre-HD. The addition of sodium azide enhanced this phenomenon. Both cellulose triacetate and polysulfone membranes did not significantly influence RBC susceptibility to oxidative stress. Neither the level of RBC reduced glutathione nor the RBC glutathione redox ratio changed significantly during HD with any of the membranes used. The RBC susceptibility to oxidative stress was influenced in different ways according to the dialysis membrane used, being increased only when using the more bioincompatible membrane Cuprophan, where neutrophil activation with increased free radical production is well documented. The alterations found in this study might contribute to the reduced RBC longevity of HD patients where a bioincompatible membrane is used.     

Patient satisfaction with mini‐implant stabilised full dentures. A 1‐year prospective study

The purpose of this study was to evaluate patient‐centred outcomes with regard to function and comfort after placement of mini‐implants for stabilisation of complete dentures. The trial was designed as a prospective cohort of 12‐months duration and involved 21 subjects in the age of 50–90 years having a full denture in the maxilla or the mandible with poor stability during function. Flapless installation of 2–4 narrow‐body Dentatus Atlas^® implants was performed and retention for the existing denture was obtained by the use of a silicone‐based soft lining material (Tuf‐Link^®). Patients' judgement of perceived satisfaction with function and comfort of the dentures was recorded at baseline, 1‐ and 12‐months post‐treatment using 10‐centimetre visual analogue scales (VAS) and a questionnaire. Clinical examination of the conditions of the peri‐implant soft tissues was performed at 12 months. Nineteen of the 21 patients were available for the 12‐month follow‐up examination. The two drop‐out subjects lost all implants within 1 month and rejected retreatment. Further six subjects lost 1–2 implants, but were sucessfully retreated by insertion of new implants. Overall satisfaction, chewing and speaking comfort were all markedly improved from pre‐treatment median VAS scores of around 4–5 to median scores of 9·0–10 (10 = optimal) at the final examination. The prevalence of positive answers to questions regarding stability/function of the denture increased significantly to almost 100% for all questions. Treatment involving maxillary dentures and the use of short implants (7–10 mm) was associated with an increased risk of implant failure. The results indicate that placement of mini‐implants as retentive elements for full dentures with poor functional stability has a marked positive impact on the patients' perception of oral function and comfort as well as security in social life.     

Performance of transcatheter pacing system use in relation to patients’ age

Journal of Interventional Cardiac Electrophysiology - Advanced non-fluoroscopic mapping systems for radiofrequency ablation (RFA) have shown to be an effective treatment of atrial fibrillation....     

Comparison of pregnenolone sulfate,pregnanolone and estradiol levels between patients with menstrually-related migraine and controls: an exploratory study

BackgroundNeurosteroids affect the balance between neuroexcitation and neuroinhibition but have been little studied in migraine. We compared the serum levels of pregnenolone sulfate, pregnanolone and estradiol in women with menstrually-related migraine and controls and analysed if a correlation existed between the levels of the three hormones and history of migraine and age.MethodsThirty women (mean age ± SD: 33.5 ± 7.1) with menstrually-related migraine (MM group) and 30 aged- matched controls (mean age ± SD: 30.9 ± 7.9) participated in the exploratory study. Pregnenolone sulfate and pregnanolone serum levels were analysed by liquid chromatography-tandem mass spectrometry, while estradiol levels by enzyme-linked immunosorbent assay.ResultsSerum levels of pregnenolone sulfate and pregnanolone were significantly lower in the MM group than in controls (pregnenolone sulfate: P = 0.0328; pregnanolone: P = 0.0271, Student’s t-test), while estradiol levels were similar. In MM group, pregnenolone sulfate serum levels were negatively correlated with history of migraine (R² = 0.1369; P = 0.0482) and age (R² = 0.2826, P = 0.0025) while pregnenolone sulfate levels were not age-related in the control group (R² = 0.04436, P = 0.4337, linear regression analysis).ConclusionLow levels of both pregnanolone, a positive allosteric modulator of the GABAA receptor, and pregnenolone sulfate, a positive allosteric modulator of the NMDA receptor, involved in memory and learning, could contribute either to headache pain or the cognitive dysfunctions reported in migraine patients. Overall, our results agree with the hypothesis that migraine is a disorder associated with a loss of neurohormonal integrity, thus supporting the therapeutic potential of restoring low neurosteroid levels in migraine treatment.Supplementary InformationThe online version contains supplementary material available at 10.1186/s10194-021-01231-9.