Evolution of social mood in Spain throughout the COVID-19 vaccination process: a machine learning approach to tweets analysis

OBJECTIVES

This paper presents a new approach based on the combination of machine learning techniques, in particular, sentiment analysis using lexicons, and multivariate statistical methods to assess the evolution of social mood through the COVID-19 vaccination process in Spain.

METHODS

Analysing 41,669 Spanish tweets posted between 27 February 2020 and 31 December 2021, different sentiments were assessed using a list of Spanish words and their associations with eight basic emotions (anger, fear, anticipation, trust, surprise, sadness, joy and disgust) and three valences (neutral, negative and positive). How the different subjective emotions were distributed across the tweets was determined using several descriptive statistics; a trajectory plot representing the emotional valence vs narrative time was also included.

RESULTS

The results achieved are highly illustrative of the social mood of citizens, registering the different emerging opinion clusters, gauging public states of mind via the collective valence, and detecting the prevalence of different emotions in the successive phases of the vaccination process.

CONCLUSIONS

The present combination in formal models of objective and subjective information would therefore provide a more accurate vision of social reality, in this case regarding the COVID-19 vaccination process in Spain, which will enable a more effective resolution of problems.

[Diagnosis of mesial temporal sclerosis with magnetic resonance imaging]

INTRODUCTION

Mesial temporal sclerosis (MTS) is a progressive drug-resistant epileptic syndrome which requires rapid, effective diagnosis and treatment. Histologically there is atrophy and gliosis of the hippocampus.

OBJECTIVE

To establish magnetic resonance (MR) imaging guidelines for correct diagnosis.

PATIENTS AND METHODS

We made a prospective study of 78 patients with drug-resistant temporal lobe epilepsy (44 women and 34 men; age 6-66 years, mean 31 years). Using a magnet of 1.5 Teslas paracoronal sections were made of the hippocampus with T1 volumetric with inversion-recovery, FLAIR (fluid-attenuated inversion-recovery) and T2 relaxometry. A control group of 30 healthy volunteers was established. The reduction in volume and hippocampal T2 hyperintensity were considered to be MTS diagnosed on MR.

RESULTS

No hippocampal differences were observed among the healthy volunteers. The confidence intervals (mean +/- 1.96 SD) were: right volume: 4.169-5.911 mm3; left volume: 4.097-5.940 mm3; time of T2 relaxation: 98-113 ms. MTS was observed in 42 patients (54%): 24 left, 14 right and four asymmetrical bilateral. The results of the diagnostic validity (sensitivity/specificity) were: T1 volumetric 91/92%, FLAIR 93.5/98% and T2 relaxometry 91/92%. There was atrophy of other extrahippocampal structures in five cases of MTS; 10 patients with MTS (23.5%) had another extrahippocampal lesion associated (dual pathology), particularly migration disorders; 21 patients (27%) had lesions without MTS (tumors, alterations of migration, nonspecific gliosis) and in 15 cases (19%) there were no abnormal findings. A total of 27 patients were operated on: 22 with MTS (21 had diagnostic MR, one case had no abnormal findings), four cases had tumors and one had cortical dysplasia.

CONCLUSION

The combination of quantitative techniques (T1 volumetric with inversion-recovery and T2 relaxometry) and FLAIR optimize MTS diagnosis using MR.

[Callosotomy in the treatment of drug-resistant epilepsy]

At the present time corpus callosotomy is a valuable option in the management of some patients with drug-resistant epilepsy who are not candidates for resective procedures. The records of six patients who underwent callosotomy at 'Hospital Virgen de las Nieves' (Granada, Spain) in the past four years were retrospectively analyzed. The patients all had intractable primary or secondarily generalized seizures, were severely handicapped by its frequency and nature (especially with drop attacks and multiple injuries) and were not suitable for other surgical procedure. The results of surgery (five anterior callosotomies and one subtotal section) are described after an average follow-up period of 2.5 years. Overall, four patients achieved significant improvement (at least 50% reduction in seizure frequency, severity, or both, affecting quality of life), with a marked reduction (> 75%) in two of them. There was no clinical deterioration, significant surgical complication nor relevant additional long-term neuro-psychological deficit in any case. Previous studies have been reviewed mainly to find those prognostic factors associated with a better seizure outcome or with the occurrence of complications. The best results are obtained in those patients with drop attacks (including atonic seizures) as the most frequent and disabling seizure type. According to the type of epilepsy, patients with localization-related epilepsy (especially when symptomatic of a focal brain damage) and those with the Lennox-Gastaut syndrome are the most likely to benefit from the procedure. It is suggested that, in the first place, a two-thirds anterior callosotomy should be performed particularly with atonic seizure are the most frequent seizure type. We may proceed with completion of callosal division as a second stage in those patients in whom a significant improvement has not been observed. In severely retarded patients with multiple seizure types, one-stage complete section may be performed. The procedure is relatively safe, with a low incidence of morbidity and clinically significant long-term neuro-psychological deficits. Further larger clinical studies are necessary to elucidate many aspects which are still unresolved. More uniformity would be desirable in the evaluation of patients, surgical technique, follow-up and presentation of results.

Plasmatic beta-endorphin levels and thalamic surgery for pain

Plasma beta-endorphin levels were found to be significantly lower in patients suffering from chronic pain of malignant etiology than in a control group. After a bilateral stereotactic cryothalamotomy in Centrum Medianum and Parafascicularis nuclei, a good clinical result and a significant increase in plasma beta-endorphin levels were obtained.

Correlation between plasmatic and CSF beta-endorphin levels

Fifty-four concomitant pairs of plasma and ventricular CSF samples were obtained in eighteen patients taking advantage of some neuroradiological or therapeutical procedures. A significant linear correlation between plasma and CSF beta-Endorphin levels has been found. The results obtained and those of other papers on the subject are discussed.

Role of the intracarotid amobarbital-pentylenetetrazol EEG test in the diagnosis and surgical treatment of patients with complex seizure problems

The results of surgical treatment of intractable epilepsy seizures in a group of patients investigated with the intracarotid amobarbital-pentylenetetrazol EEG test were analyzed. This diagnostic test, originally designed to distinguish a mechanism of primary from that of secondary bilateral synchrony in the EEG was also used in a small group of patients with independent bilateral temporal epileptiform spiking. The test has been carried out in 99 patients of which 34 were operated on. Not all the operated patients fulfilled the test criteria for secondary bilateral synchrony.