Diagnosis of multiple sclerosis using optical coherence tomography supported by explainable artificial intelligence.

BACKGROUND/OBJECTIVES: Study of retinal structure based on optical coherence tomography (OCT) data can facilitate early diagnosis of relapsing-remitting multiple sclerosis (RRMS). Although artificial intelligence can provide highly reliable diagnoses, the results obtained must be explainable. SUBJECTS/METHODS: The study included 79 recently diagnosed RRMS patients and 69 age matched healthy control subjects. Thickness (Avg) and inter-eye difference (Diff) features are obtained in 4 retinal layers using the posterior pole protocol. Each layer is divided into six analysis zones. The Support Vector Machine plus Recursive Feature Elimination with Leave-One-Out Cross Validation (SVM-RFE-LOOCV) approach is used to find the subset of features that reduces dimensionality and optimises the performance of the classifier. RESULTS: SVM-RFE-LOOCV was used to identify OCT features with greatest capacity for early diagnosis, determining the area of the papillomacular bundle to be the most influential. A correlation was observed between loss of layer thickness and increase in functional disability. There was also greater functional deterioration in patients with greater asymmetry between left and right eyes. The classifier based on the top-ranked features obtained sensitivity = 0.86 and specificity = 0.90. CONCLUSIONS: There was consistency between the features identified as relevant by the SVM-RFE-LOOCV approach and the retinotopic distribution of the retinal nerve fibres and the optic nerve head. This simple method contributes to implementation of an assisted diagnosis system and its accuracy exceeds that achieved with magnetic resonance imaging of the central nervous system, the current gold standard. This paper provides novel insights into RRMS affectation of the neuroretina.

Using advanced analysis of multifocal visual-evoked potentials to evaluate the risk of clinical progression in patients with radiologically isolated syndrome.

This study aimed to assess the role of multifocal visual-evoked potentials (mfVEPs) as a guiding factor for clinical conversion of radiologically isolated syndrome (RIS). We longitudinally followed a cohort of 15 patients diagnosed with RIS. All subjects underwent thorough ophthalmological, neurological and imaging examinations. The mfVEP signals were analysed to obtain features in the time domain (SNRmin: amplitude, Latmax: monocular latency) and in the continuous wavelet transform (CWT) domain (bmax: instant in which the CWT function maximum appears, Nmax: number of CWT function maximums). The best features were used as inputs to a RUSBoost boosting-based sampling algorithm to improve the mfVEP diagnostic performance. Five of the 15 patients developed an objective clinical symptom consistent with an inflammatory demyelinating central nervous system syndrome during follow-up (mean time: 13.40 months). The (SNRmin) variable decreased significantly in the group that converted (2.74 ± 0.92 vs. 4.07 ± 0.95, p = 0.01). Similarly, the (bmax) feature increased significantly in RIS patients who converted (169.44 ± 24.81 vs. 139.03 ± 11.95 (ms), p = 0.02). The area under the curve analysis produced SNRmin and bmax values of 0.92 and 0.88, respectively. These results provide a set of new mfVEP features that can be potentially useful for predicting prognosis in RIS patients.

Associação entre eficiência alimentar e ganho em acabamento de carcaça de bovinos da raça Nelore / Association between feed efficiency and carcass finishinging gain of Nellore cattle

Objetivou-se estimar a associação fenotípica entre a eficiência alimentar e o ganho em acabamento de carcaça de touros jovens da raça Nelore. Utilizaram-se informações de 98 touros jovens da raça Nelore, participantes de duas provas de eficiência alimentar que empregaram o sistema de cochos eletrônicos Growsafe®, as quais foram realizadas nos anos de 2015 e 2016, na fazenda Capim Branco, da Universidade Federal de Uberlândia. As provas de eficiência alimentar tiveram duração de 91 dias, sendo 21 dias de adaptação e 70 dias de avaliação. Os animais apresentavam idade média ao início e ao término do confinamento de 19,98 e 22,16 meses e peso inicial e final médio de 428,17 e 542,27kg, respectivamente. Verificou-se que os animais mais eficientes depositaram menos gordura, e os animais menos eficientes depositaram mais gordura durante o período de avaliação em confinamento. Observou-se que há uma associação fenotípica de baixa magnitude (0,29) entre o consumo alimentar residual (CAR) e o ganho em acabamento de carcaça (GACAB). Assim, pode-se inferir que, ao serem selecionados menores valores de CAR, haverá alguma interferência negativa em GACAB. Concluiu-se que animais mais eficientes (CAR negativo) podem apresentar menor deposição de gordura subcutânea, influenciando na qualidade de carcaça de bovinos da raça Nelore.(AU)

This study aimed to estimate the phenotypic association between feed efficiency and gain in carcass finishing of young Nelore bulls. Information from 98 young Nelore bulls participating in two feed efficiency tests using the Growsafe® electronic trough system, carried out in the years 2015 and 2016, at the Capim Branco farm of the Universidade Federal de Uberlândia was used .The feed efficiency tests lasted for 91 days, with 21 days of adaptation and 70 days of evaluation. The animals had a mean age at the beginning and end of the confinement of 19.98 and 22.16 months, and mean weight initial and end of 428.17 and 542.27kg, respectively. It was verified that most efficient animals deposited less fat, and the efficient animals deposited more fat during the evaluation period at the confinement. It was observed that there is a low magnitude phenotypic association (0.29) between the residual feed intake (RFI) and the gain in carcass finishing (GACAB). Thus, it can be inferred that by selecting lower values of residual feed intake there will be some negative interference in GACAB. It was concluded that the most efficient animals (negative RFI) may present lower deposition of subcutaneous fat, influencing the carcass quality of Nelore cattle.(AU)

mfERG_LAB: Software for processing multifocal electroretinography signals.

The multifocal electroretinography technique consists of performing sectorized light excitation of the retina and capturing the resulting evoked potential. This provides functional localized information about the state of the retinal neurons. Analysis of multifocal electroretinography signals can be used for diagnosing different types of optic neuropathies (glaucomatous, demyelinating and ischemic ethiology). In order to obtain a reliable diagnosis, it is necessary to apply advanced processing algorithms (morphological, frequency and time-frequency analysis, etc.) to the multifocal electroretinography signal. This paper presents a software application developed in MATLAB(®) (MathWorks Inc., MA) designed to perform advanced multifocal electroretinography signal analysis and classification. This intuitive application, mfERG_LAB, is used to plot the signals, apply various algorithms to them and present the data in an appropriate format. The application's computational power and modular structure make it suitable for use in clinical settings as a powerful and innovative diagnostic tool, as well as in research and teaching settings as a means of assessing new algorithms.

Impact of urban air pollutants and noise levels over daily hospital admissions in children in Madrid: a time series analysis.

OBJECTIVE: The aim of this paper was to analyse the effects of the urban air pollutants and noise levels on daily emergency hospital admissions of children less than 10 years of age in Madrid. MATERIAL AND METHODS: Poisson Regression Models were used to quantify the associations. Meteorological variables, influenza epidemics, pollen concentrations and trends and periodicities were used as controlling variables. RESULTS: The main results obtained were the detected relationship (p<0.05) between emergency hospital admissions due to organic diseases and noise levels (AR=2.4%) and for PM(10) concentrations (AR=2.1%). For respiratory diseases statistically significant associations were detected for noise levels (AR=4.7%) and cold temperatures (AR=3.8%). The main association detected for causes of admissions due to bronchitis was for O(3) (AR=36.8%) and for pneumonia was for noise levels (AR=7.7%). CONCLUSION: The results obtained suggest that noise level particularly is a risk factor for daily emergency hospital admissions for organic and respiratory diseases in children less than 10 years old in Madrid.

The impact of the summer 2003 heat wave in Iberia: how should we measure it?

We present a new approach to improve the reliability of quantifying the impact of a heat wave on mortality rates. We show, for the recent European summer 2003 heat wave, that the use of absolute maximum temperature values, or number of days above a given threshold, can be misleading. Here, we have assessed the impact of the heat wave on Iberian mortality by applying a four step procedure: (1) calculating, for each observatory, the local maximum temperature (T (max)) distributions, (2) calculating the corresponding 95th percentile values (T (threshold)), (3) locally defining extremely hot days (EHD) as those days on which the local threshold of the 95th percentile of the series is exceeded, and (4) calculating the total degrees-days (DD) of exceedance, by calculating the difference T (max)-T (threshold) and summing these values for all days above T (threshold). We show that the relationship between summer mortality rates and the DD index is non-linear and can be described by a logarithmic function, with a correlation coefficient of 0.78, which explains 60.6% of the mortality variance (F value of 24.64, significant at P<0.0001). Using maximum temperatures, no significant relationship is found with mortality, whereas the EHD frequency shows a significant association with mortality, albeit weaker than that obtained with DD.

Predicting average feed intake of lactating Holstein cows fed totally mixed rations.

A dry matter intake (DMI) prediction equation was estimated by using a data file that contained 124 treatment means collected from published studies. Animal factors considered for inclusion in the prediction model were body weight (BW) and its natural logarithm, BW(0.75), milk yield (MY) and its natural logarithm, milk fat and protein yields, month of lactation and its square, as well as its natural logarithm. The dietary factors considered were the percentages of neutral detergent fiber, acid detergent fiber, crude protein and hemicellulose in the ration dry matter together with the square of all these predictors. The multiple regression model selected by using the maximum R2 method include both animal and dietary factors as independent variables. The accuracy of this DMI prediction equation was evaluated and compared with that of five other equations previously published by using three independent datasets also containing treatment means collected from literature. Even though the latest NRC equation was slightly more accurate than the equation proposed in this study with the three evaluation datasets, the latter can be used for some applications for which the NRC equation is not appropriate.

Hypodermosis of red deer in Spain.

From February 1998 to January 1999, 106 red deer in the Autonomic Organism National Park "Quintos de Mora" (Toledo, central Spain) were evaluated to determine the prevalence and dynamics of infection with Hypoderma sp. by detection of subcutaneous larvae. Between six and 13 deer shot in selective hunting were examined monthly. Hypoderma sp. larvae were detected throughout the period except in June, July and August of 1998. Excluding the period during which no subcutaneous larvae were detected, the number of animals sampled was 80 (52 males and 28 females), belonging to three age classes: 12 calves (<1-yr-old), 19 yearlings (1-yr-old), and 49 adults (2- to 10-yr-old). All the third instar (L3) collected were identified as H. actaeon. Total prevalence during the period of larval detection was 61%. Prevalence in yearling and adult deer shot during the official hunting season was 89%. Monthly prevalence increased from September to January and decreased from February to May. In September and October, a small percentage of larvae were classified as first instar (L1). The rest of larvae collected between September and December were second instar (L2). Third instar (L3) predominated in January and February and was the only stage collected from March to May. Intensity ranged from 1 to 145 larvae. Intensities were >100 larvae in 6% of animals. Possible relationships of intensity or prevalence of infection with sex or age of the animals were evaluated. Significant differences in prevalence were observed among different host age classes. Prevalence was higher in yearlings (84%) than in adults (63%) and lowest in calves (17%).

Elaeophorosis in red deer from Spain.

Elaeophorosis, caused by Elaeophora elaphi, was observed in red deer (Cervus elaphus) from Toledo Province (Spain) for the first time. Adult specimens of Elaeophora elaphi were found in the hepatic vessels of nine of 151 red deer between October 1994 and September 1995; intensity of infection was two to 18 nematodes per host. Adult nematodes were only found during the period from fall through early spring. No differences were present between sex or age groups. Parasites were not found in a limited sample from fallow deer (Dama dama). Blood samples were negative for the presence of microfilariae.

Pharyngeal bot flies in Cervus elaphus in central Spain: prevalence and population dynamics.

The prevalence and intensity of infestations by bot flies Pharyngomyia picta and Cephenemyia auribarbis in red deer (Cervus elaphus) from Quintos de Mora (Toledo, Spain) were determined over a 1-yr period. Bots were present all year. No clear correlations were found between age or sex of the host and parasitization levels (prevalence and intensity). Considerable variation was found in prevalence and intensity, with larger values from December to March. Cephenemyia auribarbis was restricted from November to March, with maximum numbers of L-3 in February. Pharyngomyia picta showed a more complex profile with 2 peaks (March and August), indicating 2 generations per year.

[The adverse effects of antihypertensive therapy: the perception of patients]. / Efeitos adversos da terapêutica anti-hipertensiva: a percepção dos doentes.

OBJECTIVES: To determine the prevalence of side effects of antihypertensive therapy as patients perceive them, their distribution and association with several sociodemographic and clinical characteristics. DESIGN: Cross-sectional survey, made by telephone on a randomized sample of national scale, selected from the telephone directories. PARTICIPANTS: Of a randomized sample of 4480 people contacted, 3374 were interviewed, and 1425 hypertensive patients were identified. Of this group, 1000 (70%) completed the interview, and 425 (30%) refused to participate. METHODS: Patients were interviewed by telephone by a company of market studies. Epi Info was used for statistical analysis. Associations between the occurrence of side effects and the sociodemographic and clinical variables were analysed by logistic regression. MAIN RESULTS: 44.3% of the patients surveyed (45.6% male and 43.6% female), experienced side effects. These were more common among the youngest (50.4%) and the oldest (45.5%). There was a tendency towards an inverse relationship with social class and a significant association (p = 0.009) with the region of residence, the South showing the lowest rate of side effects (26.3%). The analysis of the associations between side effects and the clinical variables showed that only the regularity of medication was close to statistical significance (p = 0.06). The other clinical variables (time since knowledge of hypertension, substitution of medication, number of drugs and current medication) did not show any association with the perception of side effects. CONCLUSIONS: This study showed a high prevalence of side effects referred by patients under antihypertensive therapy (44.3%). Among several sociodemographic and clinical characteristics, the only significant statistical association found was with region of residence (the South with the lowest rate). The patients' perception of side effects of antihypertensive therapy is admitted as a potential conditioner of compliance and a cause for deficient blood pressure control to be prevented.

[Risk factors for cerebrovascular stroke in a cohort of hypertensive patients]. / Factores de risco de acidente vascular cerebral numa coorte de hipertensos.

OBJECTIVES: To identify stroke risk factors in hypertensive patients and the probability of stroke in relation to those risk factors and follow-up. STUDY DESIGN: A cohort study (patients with high blood pressure). MATERIAL AND METHODS: 707 hypertensive patients were studied (Hypertension Register) in what concerns stroke incidence until 1992 (n = 126), considering one case per individual. The following variables were analysed: age, sex, body mass index (Quetelet), systolic and diastolic blood pressure, heart rate, types of hypertension (JNC-IV), left ventricular hypertrophy, changes in ST segment and T wave (Minnesota Code), fundi, angina pectoris, heart failure, central nervous (neurological) disturbances, antihypertensive treatment, smoking, serum potassium, serum sodium, blood urea, creatinine, uric acid, blood sugar, diabetes and cholesterol, in the initial record. Individually, in relation to the control of hypertension, the subjects were classified according to the casual recording of normal blood pressure, the absence of drug treatment, diastolic pressure > 114 mmHg and, at the end of 1992, according to survival, causes of death and follow-up. Stroke risk factors have been identified by multivariate analysis (Cox regression model). The survival probability (without stroke) was defined by Kaplan-Meier method. RESULTS: It was possible to maintain the epidemiological surveillance, from 1975 to 1992, of 598 cases. From those, 109 hypertensive patients were victims of at least one episode of non transient cerebral ischaemia, during their follow-up of 10.5 years. From the characteristics studied, only five were identified at risk factors. The adjusted relative risks and confidence intervals (95% CI) were the following: age: 1.08 (1.06-1.10); diastolic pressure > 114 mmHg: 1.96 (1.32-2.91); neurological disturbances 4.64 (2.99-7.2); diabetes: 2.57 (1.62-4.05) and left ventricular hypertrophy: 1.34 (1.13-1.58). CONCLUSIONS: As far as stroke is concerned: a) Age, diabetes, a casual measurement of diastolic blood pressure > 114 mmHg and left ventricular hypertrophy (electrocardiogram) were the risk factors identified; b) Prevention should include blood pressure and diabetes control, although this disease has shown more risk than a casual measurement of severe hypertension; c) Its occurrence, in this model, has only partly been explained, therefore it has become necessary to deepen the study of the risk profile.

[Angina pectoris. The extent of the problem]. / Angina de peito. A dimensão do problema.

Angina pectoris is analysed according to the principal data of its social repercussion: frequency, gravity, chronicity, diagnostic and treatment complexity, treatment costs and genetic factor extension. Some data of the national literature defining the dimension of the problem are given and a comparative study with other diseases and other countries is made. In conclusion, the need to develop epidemiological studies of adequate dimension is supported, mostly to better define frequency of the disease (prevalence and incidence) since the hospital and the mortality data are not enough. However, from the available data, it is expected that the prevalence of ischemic heart disease, of which the angina is a frequent clinical manifestation, will increase as well as the economic costs. In fact, the costs will be the consequence of scientific and technological development and of the increasing search for health by the population can services.

Isradipine in the treatment of mild-to-moderate hypertension in geriatric patients.

A number of studies have shown the benefit of hypertensive treatment even though the most common forms of the disease are mild-to-moderate in severity. Considering the overall aging of the world's population, it is of particular interest to study hypertension and its treatment in geriatric patients. A short-term study of isradipine was conducted to assess its effectiveness and tolerability in patients with mild-to-moderate hypertension. The study was carried out by general practitioners and involved 3343 patients, aged > or = 18 years, with diastolic blood pressures (DBPs) ranging from 95 to 114 mm Hg. A 4-week wash-out and placebo run-in phase was followed by a 12-week active treatment period with isradipine at 1.25 or 2.5 mg/day, depending on the blood pressure response. Posttreatment results in a subgroup of 1092 patients (444 men and 648 women), aged > or = 60 years, showed decreases in systolic blood pressure (SBP) from 173.1 to 149.2 mm Hg (mean decrease, 20.9 mm Hg) and, in DBP, from 102.0 to 85.0 mm Hg (mean decrease, 16.9 mm Hg). The majority (84.6%) of these patients showed DBP reductions of > 10 mm Hg, and 82.3% achieved normalization (DBP < 90 mm Hg) at the end of treatment. The mean dosage was 1.74 +/- 0.69 mg twice daily, and 37% of patients doubled their initial 1.25 mg twice daily dosages. There were no significant changes in either heart rate or major metabolic parameters. Adverse events were reported by 3.1% of the patients, and 90% of both patients and physicians expressed satisfaction with the therapy. There were no differences between men and women with regard to adverse events or efficacy, nor were the results in patients > or = 60 years different from those in younger patients. Thus, isradipine was effective and well tolerated in these geriatric patients.

[The evolution of mortality from ischemic heart disease and cerebrovascular diseases in Portugal in the decade of the 80s]. / Evolução da mortalidade por doença isquémica cardíaca e doenças cerebro-vasculares em Portugal, na década de 80.

By late 70's, Portugal had one of the lowest IHD mortality rates amongst developed countries, with a declining trend. As for CVD, Portugal's figures were one of the highest, and showing a trend to increase. In what concerns to our country, by early 80's there were some data showing important regional variations concerning IHD and CVD mortality. So, the aims of this study were to analyse the evolution of IHD and CVD mortality rates in Portugal during the 80's and its possible relations with known risk factors evolution and distribution. The study also observed regional variations and regional mortality excesses, and international comparisons were established. During the studied decade, CVD and IHD were the leading causes of death in Portugal, with a ratio of 2.7/l respectively. There was a 24% decrease in CVD death rates, and 11% for IHD, equal for male and female. We found important differences amongst age groups: CVD predominates in extreme ages (the youngest and the oldest), whereas IHD predominates only in men 25-54 years old. We also found striking differences between provinces: in the northern coast CVD predominates, whereas in the South and Azores islands IHD leads. At the end of the decade, CVD mortality rates in Portugal where the highest in Europe; on the contrary, IHD mortality was the second lowest, just after France. This pattern is similar to the southern countries of Europe and Japan. Trends in the main cardiovascular risk factors in Portugal during the 80s are an incomplete explanation for this evolution pattern, although the authors value the suggested decrease in arterial hypertension prevalence as the main factor responsible for the observed reduction in IHD and CVD mortality in the country.