Somatostatin-Positive Interneurons Contribute to Seizures in SCN8A Epileptic Encephalopathy.

SCN8A epileptic encephalopathy is a devastating epilepsy syndrome caused by mutant SCN8A, which encodes the voltage-gated sodium channel NaV1.6. To date, it is unclear if and how inhibitory interneurons, which express NaV1.6, influence disease pathology. Using both sexes of a transgenic mouse model of SCN8A epileptic encephalopathy, we found that selective expression of the R1872W SCN8A mutation in somatostatin (SST) interneurons was sufficient to convey susceptibility to audiogenic seizures. Patch-clamp electrophysiology experiments revealed that SST interneurons from mutant mice were hyperexcitable but hypersensitive to action potential failure via depolarization block under normal and seizure-like conditions. Remarkably, GqDREADD-mediated activation of WT SST interneurons resulted in prolonged electrographic seizures and was accompanied by SST hyperexcitability and depolarization block. Aberrantly large persistent sodium currents, a hallmark of SCN8A mutations, were observed and were found to contribute directly to aberrant SST physiology in computational modeling and pharmacological experiments. These novel findings demonstrate a critical and previously unidentified contribution of SST interneurons to seizure generation not only in SCN8A epileptic encephalopathy, but epilepsy in general.SIGNIFICANCE STATEMENTSCN8A epileptic encephalopathy is a devastating neurological disorder that results from de novo mutations in the sodium channel isoform Nav1.6. Inhibitory neurons express NaV1.6, yet their contribution to seizure generation in SCN8A epileptic encephalopathy has not been determined. We show that mice expressing a human-derived SCN8A variant (R1872W) selectively in somatostatin (SST) interneurons have audiogenic seizures. Physiological recordings from SST interneurons show that SCN8A mutations lead to an elevated persistent sodium current which drives initial hyperexcitability, followed by premature action potential failure because of depolarization block. Furthermore, chemogenetic activation of WT SST interneurons leads to audiogenic seizure activity. These findings provide new insight into the importance of SST inhibitory interneurons in seizure initiation, not only in SCN8A epileptic encephalopathy, but for epilepsy broadly.

Influenza vaccination during the coronavirus pandemic: intention to vaccinate among the at-risk population in the Central Catalonia Health Region (VAGCOVID).

BACKGROUND: Influenza is a major public health issue, with the primary preventive measure being an annual influenza vaccination. Nevertheless, vaccination coverage among the at-risk population is low. Our understanding of the behaviour of the influenza virus during the SARS-CoV-2 coronavirus pandemic is limited, meaning influenza vaccination is still recommended for individuals at risk for severe complications due to influenza infection. The aim of the study is to determine the intention to vaccinate against seasonal influenza among the at-risk population in the 2020-21 campaign during the SARS-CoV-2 pandemic and to analyse the factors which influence such intention. METHODS: Cross-sectional telephone survey of adults (aged over 18) with risk factors in central Catalonia where the need for the Seasonal Influenza Vaccine (SIV) was recommended. RESULTS: A total of 434 participants responded to the survey, 43.3% of whom intended to be vaccinated against influenza for the 2020-2021 influenza season, 40.8% had no intention to be vaccinated and 15.9% were uncertain or did not express their opinion. The intention to get vaccinated against influenza is associated with having dependents, the individual's perception of the risk of being infected with influenza and the perceived risk of transmission to dependents. It is also associated with age, whether the individual had received influenza vaccine the previous season or any other season before. The best predictors of the intention to vaccinate are the individual's perception of the risk of catching influenza and whether the individual had been vaccinated in the previous season. CONCLUSIONS: Intention to vaccinate can be a good predictor of individual behaviour in relation to vaccination. During the current SARS-CoV-2 pandemic many individuals are hesitant to influenza vaccination. In order to improve influenza vaccination coverage in people included in risk groups, it is necessary to promote educational actions, especially among those who express doubts.

The problematic use of Information and Communication Technologies (ICT) in adolescents by the cross sectional JOITIC study.

BACKGROUND: The emerging field of Information and Communications Technology (ICT) has brought about new interaction styles. Its excessive use may lead to addictive behaviours. The objective is to determine the prevalence of the problematic use of ICT such as Internet, mobile phones and video games, among adolescents enrolled in mandatory Secondary Education (ESO in Spanish) and to examine associated factors. METHODS: Cross sectional, multi-centric descriptive study. POPULATION: 5538 students enrolled in years one to four of ESO at 28 schools in the Vallès Occidental region (Barcelona, Spain). DATA COLLECTION: self-administered socio-demographic and ICT access questionnaire, and validated questionnaires on experiences related to the use of the Internet, mobile phones and video games (CERI, CERM, CERV). RESULTS: Questionnaires were collected from 5,538 adolescents between the ages of 12 and 20 (77.3 % of the total response), 48.6 % were females. Problematic use of the Internet was observed in 13.6 % of the surveyed individuals; problematic use of mobile phones in 2.4 % and problematic use in video games in 6.2 %. Problematic Internet use was associated with female students, tobacco consumption, a background of binge drinking, the use of cannabis or other drugs, poor academic performance, poor family relationships and an intensive use of the computer. Factors associated with the problematic use of mobile phones were the consumption of other drugs and an intensive use of these devices. Frequent problems with video game use have been associated with male students, the consumption of other drugs, poor academic performance, poor family relationships and an intensive use of these games. CONCLUSIONS: This study offers information on the prevalence of addictive behaviours of the Internet, mobile phones and video game use. The problematic use of these ICT devices has been related to the consumption of drugs, poor academic performance and poor family relationships. This intensive use may constitute a risk marker for ICT addiction.

[Access and use of new information and telecommunication technologies among teenagers at high school, health implications. JOITIC Study]. / Acceso y uso de nuevas tecnologías entre los jóvenes de educación secundaria, implicaciones en salud. Estudio JOITIC.

OBJECTIVE: To determine ICT accessibility and use among the adolescents attending High School and to analyse related factors. DESIGN: Cross-sectional multicentric study. SETTING: High Schools participating in the Community Health «Salut i Escola¼ Programme. PARTICIPANTS: 5,538 students from first to fourth degree at 28 centres in the area of Barcelona. MAIN MEASUREMENTS: Self administered questionnaire including sociodemographic information, ICT use and accessibility. RESULTS: Missing answers were below 1% in all items except in school performance (3,13%); 48,6% were female, mean age 14years (range 11-20); 15,5% foreigners; 23% reported low school performance; 75,2% took extracurricular activities; 88,9% refers a good relationship with their parents. ICT access is homogeneously massive: 98% had a computer at home, 44,8% used it for two or more hours daily. 98,6% could access Internet, 47,2% without parental control. 90% owned a mobile phone (83% in first grade, 95% in fourth); 45,6% owned one before 12years old. Girls use it for social relationships and boys for playing. 68,4% played videogames, 36,5% for three or more hours a week and 66,8% without parental control. Their use decreases with age. The ICT parental control is associated with better school performance. CONCLUSIONS: Our high scholars gain access to the ICT at younger ages and they use them in almost every aspect of their lives. There have been detected some gender differences in their use, as well as in the age of the users and between the type of school.

[The Questionnaire of Experiences Associated with Video games (CERV): an instrument to detect the problematic use of video games in Spanish adolescents]. / El Cuestionario de Experiencias Relacionadas con los Videojuegos (CERV): un instrumento para detectar el uso problemático de videojuegos en adolescentes españoles.

The aim of this study is to validate the Video Game-Related Experiences Questionnaire (CERV in Spanish). The questionnaire consists of 17 items, developed from the CERI (Internet-Related Experiences Questionnaire - Beranuy and cols.), and assesses the problematic use of non-massive video games. It was validated for adolescents in Compulsory Secondary Education. To validate the questionnaire, a confirmatory factor analysis (CFA) and an internal consistency analysis were carried out. The factor structure shows two factors: (a) Psychological dependence and use for evasion; and (b) Negative consequences of using video games. Two cut-off points were established for people with no problems in their use of video games (NP), with potential problems in their use of video games (PP), and with serious problems in their use of video games (SP). Results show that there is higher prevalence among males and that problematic use decreases with age. The CERV seems to be a good instrument for the screening of adolescents with difficulties deriving from video game use. Further research should relate problematic video game use with difficulties in other life domains, such as the academic field.

Parvalbumin Interneuron Impairment Leads to Synaptic Transmission Deficits and Seizures in SCN8A Epileptic Encephalopathy.

SCN8A epileptic encephalopathy (EE) is a severe epilepsy syndrome resulting from de novo mutations in the voltage-gated sodium channel Na v 1.6, encoded by the gene SCN8A . Na v 1.6 is expressed in both excitatory and inhibitory neurons, yet previous studies have primarily focused on the impact SCN8A mutations have on excitatory neuron function, with limited studies on the importance of inhibitory interneurons to seizure onset and progression. Inhibitory interneurons are critical in balancing network excitability and are known to contribute to the pathophysiology of other epilepsies. Parvalbumin (PV) interneurons are the most prominent inhibitory neuron subtype in the brain, making up about 40% of inhibitory interneurons. Notably, PV interneurons express high levels of Na v 1.6. To assess the role of PV interneurons within SCN8A EE, we used two mouse models harboring patient-derived SCN8A gain-of-function mutations, Scn8a D/+ , where the SCN8A mutation N1768D is expressed globally, and Scn8a W/+ -PV, where the SCN8A mutation R1872W is selectively expressed in PV interneurons. Expression of the R1872W SCN8A mutation selectively in PV interneurons led to the development of spontaneous seizures in Scn8a W/+ -PV mice and seizure-induced death, decreasing survival compared to wild-type. Electrophysiology studies showed that PV interneurons in Scn8a D/+ and Scn8a W/+ -PV mice were susceptible to depolarization block, a state of action potential failure. Scn8a D/+ and Scn8a W/+ -PV interneurons also exhibited increased persistent sodium current, a hallmark of SCN8A gain-of-function mutations that contributes to depolarization block. Evaluation of synaptic connections between PV interneurons and pyramidal cells showed an increase in synaptic transmission failure at high frequencies (80-120Hz) as well as an increase in synaptic latency in Scn8a D/+ and Scn8a W/+ -PV interneurons. These data indicate a distinct impairment of synaptic transmission in SCN8A EE, potentially decreasing overall cortical network inhibition. Together, our novel findings indicate that failure of PV interneuron spiking via depolarization block along with frequency-dependent inhibitory synaptic impairment likely elicits an overall reduction in the inhibitory drive in SCN8A EE, leading to unchecked excitation and ultimately resulting in seizures and seizure-induced death.

Acceptance or rejection of vaccination against influenza and SARS-CoV2 viruses among primary care professionals in Central Catalonia. A cross-sectional study.

Background: With the outbreak of the SARS-CoV-2 pandemic, the uncertainty about the real impact of coinfection with other viruses, and the increased risk of mortality in the case of coinfection with the influenza virus, health authorities recommended an increase in influenza vaccination coverage among at-risk groups to minimize the possible impact on individuals and the healthcare system. Recommendations for influenza vaccination during the 2020-2021 campaign in Catalonia were focused on increasing vaccination coverage, especially for social and healthcare workers, elderly people and at-risk individuals of any age. The objectives for the 2020-2021 season in Catalonia were to reach 75 % for the elderly and for social and healthcare workers, and 60 % for pregnant women and at-risk groups. In the case of healthcare professionals and those over 65 years of age, the target was not met. Vaccination coverage reached 65.58 % and 66.44 %, respectively (in the 2019-2020 campaign it was 39.08 %).Analysing and following up on the background and context in which health professionals accept influenza vaccination will help develop strategies for long-term influenza vaccination campaigns. The present study looks at healthcare professionals in a specific territory where the reasons for acceptance or refusal of the influenza vaccine during the 2021-2022 vaccination campaign, as well as the reasons for acceptance or refusal of the COVID-19 vaccine, were analysed by means of an online survey. Methods: Calculations suggested that a random sample of 290 individuals would be sufficient to estimate, with 95% confidence and a precision of +/- 5 percentage units, a population percentage that was expected to be around 30%. The required replacement rate was 10%.The R statistical software (version 3.6.3) was used for the statistical analysis. Confidence intervals were 95 % and contrasts with a p-value of < 0.05 were considered significant. Findings: Of the 1921 professionals to whom the survey was sent, 586 (30.5%) responded to all the questions. 95.2% of respondents were vaccinated against COVID-19 and 66.2% against influenza.It was observed that the relationship between sociodemographic characteristics and the decision to get vaccinated was different for influenza and COVID-19. The reasons for accepting the COVID-19 vaccine with the highest percentage were firstly protecting family (82.2%), self-protection (74.9%) and also protecting patients (57.8%). Otherwise, other reasons not described in the survey (50%) and mistrust (42.3%) were the reasons for rejecting the COVID-19 vaccine.Regarding influenza, the most relevant reasons for which professionals got vaccinated were self-protection (70.7%), protecting family (69.7%) and protecting patients (58.4%). Reasons for refusing the influenza vaccine were reasons not mentioned in the survey (29.1%) and the low probability of suffering complications (27.4%). Interpretation: Analysing the context, territory, sector, and the reasons for both accepting and refusing a vaccine will help develop effective strategies. Although vaccination coverage against COVID-19 was very high throughout Spain, a marked increase in influenza vaccination in the context of COVID-19 was observed among healthcare professionals in the Central Catalonia region compared to the previous pre-pandemic campaign.

Effect of the historic Spanish heatwave over glycemic control in adult patients with type 1 diabetes.

AIM: To evaluate the effect of the historic Spanish heatwave (9th-26th July 2022) over glycemic control in adults with type 1 diabetes (T1D). METHODS: Cross-sectional retrospective analysis of adult patients with T1D in Castilla-La Mancha (south-central Spanish region) using intermittently scanned continuous glucose monitoring (isCGM) during and after the heatwave. Primary outcome was change in time in range (TIR) 3.0-10 mmol/L (70-180 mg/dL) of interstitial glucose in the two weeks following the heatwave. RESULTS: A total of 2701 T1D patients were analyzed. We detected a TIR reduction of 4.0 % (95 % CI -3.4, -4.6; P < 0.001) in the two weeks following the heatwave. Patients in the highest daily scan frequency quartile (>13 scans/day) during the heatwave showed the greatest deterioration in TIR after it concluded (-5.4 % [95 % CI -6.5, -4.3; P < 0.001]). The percentage of patients meeting all the recommendations of the International Consensus of Time in Range was greater during the heatwave than after it ended (10.6 % vs. 8.4 %, P < 0.001). CONCLUSIONS: Adults with T1D had better glycemic control during the historic Spanish heatwave compared to the following period.

Forebrain epileptiform activity is not required for seizure-induced apnea in a mouse model of Scn8a epilepsy.

Sudden unexpected death in epilepsy (SUDEP) accounts for the deaths of 8-17% of patients with epilepsy. Although the mechanisms of SUDEP are essentially unknown, one proposed mechanism is respiratory arrest initiated by a convulsive seizure. In mice, we have previously observed that extended apnea occurs during the tonic phase of seizures. Although often survived, tonic seizures became fatal when breathing did not immediately recover postictally. We also found that respiratory muscles were tonically contracted during the apnea, suggesting that muscle contraction could be the cause of apnea. In the present study, we tested the hypothesis that pyramidal neurons of the motor cortex drive motor units during the tonic phase, which produces apnea. Mice harboring the patient-derived N1768D point mutation of an Scn8a allele were crossed with transgenic mice such that inhibitory Designer Receptors Exclusively Activated by Designer Drugs (DREADD) receptors were selectively expressed in excitatory forebrain neurons. We then triggered audiogenic and hippocampal (HC) stimulated seizures under control conditions and when excitatory forebrain neurons were inhibited with the synthetic ligand Clozapine-N-Oxide (CNO). We found that inhibition with CNO was sufficient to increase seizure threshold of HC stimulated, but not audiogenic, seizures. In addition, regardless of seizure type, CNO nearly eliminated epileptiform activity that occurred proximal to the tonic phase; however, the seizure behaviors, notably the tonic phase and concomitant apnea, were unchanged. We interpret these results to indicate that while cortical neurons are likely critical for epileptogenesis and seizure initiation, the behavioral manifestations of tonic seizures are generated by neural circuitry in the mid- and/or hindbrain.

Astrocyte reactivity in a mouse model of SCN8A epileptic encephalopathy.

OBJECTIVE: SCN8A epileptic encephalopathy is caused predominantly by de novo gain-of-function mutations in the voltage-gated sodium channel Nav 1.6. The disorder is characterized by early onset of seizures and developmental delay. Most patients with SCN8A epileptic encephalopathy are refractory to current anti-seizure medications. Previous studies determining the mechanisms of this disease have focused on neuronal dysfunction as Nav 1.6 is expressed by neurons and plays a critical role in controlling neuronal excitability. However, glial dysfunction has been implicated in epilepsy and alterations in glial physiology could contribute to the pathology of SCN8A encephalopathy. In the current study, we examined alterations in astrocyte and microglia physiology in the development of seizures in a mouse model of SCN8A epileptic encephalopathy. METHODS: Using immunohistochemistry, we assessed microglia and astrocyte reactivity before and after the onset of spontaneous seizures. Expression of glutamine synthetase and Nav 1.6, and Kir 4.1 channel currents were assessed in astrocytes in wild-type (WT) mice and mice carrying the N1768D SCN8A mutation (D/+). RESULTS: Astrocytes in spontaneously seizing D/+ mice become reactive and increase expression of glial fibrillary acidic protein (GFAP), a marker of astrocyte reactivity. These same astrocytes exhibited reduced barium-sensitive Kir 4.1 currents compared to age-matched WT mice and decreased expression of glutamine synthetase. These alterations were only observed in spontaneously seizing mice and not before the onset of seizures. In contrast, microglial morphology remained unchanged before and after the onset of seizures. SIGNIFICANCE: Astrocytes, but not microglia, become reactive only after the onset of spontaneous seizures in a mouse model of SCN8A encephalopathy. Reactive astrocytes have reduced Kir 4.1-mediated currents, which would impair their ability to buffer potassium. Reduced expression of glutamine synthetase would modulate the availability of neurotransmitters to excitatory and inhibitory neurons. These deficits in potassium and glutamate handling by astrocytes could exacerbate seizures in SCN8A epileptic encephalopathy. Targeting astrocytes may provide a new therapeutic approach to seizure suppression.

Influenza vaccination in coronavirus times: Primary Care professionals' intention to get vaccinated in Central Catalonia (VAGCOVID). A cross sectional study.

Influenza vaccination is the main measure of prevention against epidemic flu. Although recommended, vaccination coverage remains low. The lack of knowledge about the evolution of influenza in the context of the SARS-CoV-2 coronavirus pandemic led to the recommendation of influenza vaccination to people at risk and professionals to avoid a greater burden than the one already posed by SARS-CoV-2. The aim of the study is to determine health professionals' intention to vaccinate against seasonal flu in the 2020-2021 campaign, in the context of the SARS-CoV-2 pandemic, and to analyse the factors that influence it. Cross-sectional study through a structured survey aimed at Primary Care professionals in Central Catalonia. A total of 610 participants responded to the survey, 65.7% of whom intended to get vaccinated against influenza in this campaign, and 11.1% did not know or did not answer. The intention to get vaccinated is associated with the professional category and the number of years of professional practice. The profile of the professionals who intend to get vaccinated against flu includes professionals with a history of vaccination, who participate in on-call duties and perceive that their dependents were at risk of becoming ill. During the SARS-CoV-2 pandemic, although almost two-thirds of the respondents showed a clear intention to get vaccinated against influenza, 11% were doubtful. To improve influenza vaccination uptake among health professionals, strategies need to be devised to target those professionals who are hesitant or reluctant to vaccinate.

Effectiveness of a brief intervention for acceptance of influenza vaccine in reluctant primary care patients.

OBJECTIVE: To determine the effectiveness of a brief intervention in increasing influenza vaccination coverage compared with the usual advice in people who refuse it, and to record the main reasons for refusing to be vaccinated. METHOD: A cluster randomized clinical trial was conducted in which the study population was individuals with high risk factors who initially had refused to be vaccinated against influenza. Professionals (doctors and nurses) who voluntarily accepted to participate were assigned randomly to the intervention group (brief intervention) and the control group (usual advice). RESULTS: 57 professionals recruited 524 people who had previously declined the influenza vaccination (271 in the control group and 253 in the intervention group). Brief intervention showed its effectiveness with an odds ratio of 2.48 (1.61-3.82; p<0.001), in individuals aged 60 or over, both healthy or with risk factors. The most frequent reasons for rejection of vaccination were the belief that there was no risk of getting sick (53.0%) and the fear of the side effects (33.3%). CONCLUSIONS: Brief intervention is an effective tool in improving vaccination coverage in people who have initially rejected it.

Identification of Resistance to Exogenous Thyroxine in Humans.

Background: Thyroxine (T4) to triiodothyronine (T3) deiodination in the hypothalamus/pituitary is mediated by deiodinase type-2 (D2) activity. Dio2(-/-) mice show central resistance to exogenous T4. Patients with resistance to exogenous thyroxine (RETH) have not been described. The aim of this study was to identify hypothyroid patients with thyrotropin (TSH) unresponsiveness to levothyroxine (LT4) and to characterize the clinical, hormonal, and genetic features of human RETH. Methods: We investigated hypothyroid patients with elevated TSH under LT4 treatment at doses leading to clinical and/or biochemical hyperthyroidism. TSH and free T4 (fT4) were determined by chemiluminescence, and total T4, T3, and reverse T3 (rT3) by radioimmunoassay. TSH/fT4 ratio at inclusion and T3/T4, rT3/T4, and T3/rT3 ratios at follow-up were compared with those from patients with resistance to thyroid hormone (RTH) due to thyroid hormone receptor-ß (THRB) mutations. DIO2, including the Ala92-D2 polymorphism, selenocysteine binding protein 2 (SECISBP2), and THRB were fully sequenced. Results: Eighteen hypothyroid patients (nine of each sex, 3-59 years) treated with LT4 showed elevated TSH (15.5 ± 4.7 mU/L; reference range [RR]: 0.4-4.5), fT4 (20.8 ± 2.4 pM; RR: 9-20.6), and TSH/fT4 ratio (0.74 ± 0.25; RR: 0.03-0.13). Despite increasing LT4 doses from 1.7 ± 1.0 to 2.4 ± 1.7 µg/kg/day, TSH remained elevated (6.9 ± 2.7 mU/L). Due to hyperthyroid symptoms, LT4 doses were reduced, and TSH increased again to 7.9 ± 3.2 mU/L. In the euthyroid/hyperthyrotropinemic state, T3/T4 and T3/rT3 ratios were decreased (9.2 ± 2.4, RR: 11.3-15.3 and 2.5 ± 1.4, RR: 7.5-8.5, respectively) whereas rT3/T4 was increased (0.6 ± 0.2; RR: 0.43-0.49), suggesting reduced T4 to T3 and increased T4 to rT3 conversion. These ratios were serum T4-independent and were not observed in RTH patients. Genetic testing was normal. The Ala92-D2 polymorphism was present in 7 of 18 patients, but the allele dose did not correlate with RETH. Conclusions: Human RETH is characterized by iatrogenic thyrotoxicosis and elevated TSH/fT4 ratio. In the euthyroid/hyperthyrotropinemic state, it is confirmed by decreased T3/T4 and T3/rT3 ratios, and elevated rT3/T4 ratio. This phenotype may guide clinicians to consider combined T4+T3 therapy in a targeted fashion. The absence of germline DIO2 mutations suggests that aberrant post-translational D2 modifications in pituitary/hypothalamus or defects in other genes regulating the T4 to T3 conversion pathway could be involved in RETH.