Influence of Random Plasmonic Metasurfaces on Fluorescence Enhancement

One of the strategies employed to increase the sensitivity of the fluorescence-based biosensors is to deposit chromophores on plasmonic metasurfaces which are periodic arrays of resonating nano-antennas that allow the control of the electromagnetic field leading to fluorescence enhancement. While artificially engineered metasurfaces realized by micro/nano-fabrication techniques lead to a precise tailoring of the excitation field and resonant cavity properties, the technological overhead, small areas, and high manufacturing cost renders them unsuitable for mass production. A method to circumvent these challenges is to use random distribution of metallic nanoparticles sustaining plasmonic resonances, which present the properties required to significantly enhance the fluorescence. We investigate metasurfaces composed of random aggregates of metal nanoparticles deposited on a silicon and glass substrates. The finite difference time domain simulations of the interaction of the incident electromagnetic wave with the structures reveals a significant enhancement of the excitation field, which is due to the resonant plasmonic modes sustained by the nanoparticles aggregates. We experimentally investigated the role of these structures in the fluorescent behaviour of Rhodamine 6G dispersed in polymethylmethacrylate finding an enhancement that is 423-fold. This suggests that nanoparticle aggregates have the potential to constitute a suitable platform for low-cost, mass-produced fluorescent biosensors.     

Immunogenicity Following Administration of BNT162b2 and Ad26.COV2.S COVID-19 Vaccines in the Pregnant Population during the Third Trimester

Globally, COVID-19 vaccines are currently being used to prevent transmission and to reduce morbidity and death associated with SARS-CoV-2 infection. Current research reveals that vaccines such as BNT162b2 and Ad26.COV2.S are highly immunogenic and have high short-term effectiveness for most of the known viral variants. Clinical trials showed satisfying results in the general population, but the reluctance in testing and vaccinating pregnant women left this category with little evidence regarding the safety, efficacy, and immunogenicity following COVID-19 vaccination. With the worldwide incidence of COVID-19 remaining high and the possibility of new transmissible SARS-CoV-2 mutations, data on vaccination effectiveness and antibody dynamics in pregnant patients are critical for determining the need for special care or further booster doses. An observational study was developed to evaluate pregnant women receiving the complete COVID-19 vaccination scheme using the BNT162b2 and Ad26.COV2.S, and determine pregnancy-related outcomes in the mothers and their newborns, as well as determining adverse events after vaccination and immunogenicity of vaccines during four months. There were no abnormal findings in pregnancy and newborn characteristics comparing vaccinated versus unvaccinated pregnant women. COVID-19 seropositive pregnant women had significantly higher spike antibody titers than seronegative patients with similar characteristics, although they were more likely to develop fever and lymphadenopathy following vaccination. The same group of pregnant women showed no statistically significant differences in antibody titers during a 4-month period when compared with case-matched non-pregnant women. The BNT162b2 and Ad26.COV2.S vaccines are safe to administer during the third trimester of pregnancy, while their safety, efficacy, and immunogenicity remain similar to those of the general population.     

Video-assisted thoracoscopic thymectomy--preliminary results

Video-assisted thoracoscopic surgery (VATS) provides a new approach to thymectomy. From April 1999 to December 1999, we performed a total of 10 video-assisted thoracoscopic thymectomies for myasthenia gravis (MG). There were one male and nine female patients with ages ranging from 8 to 59 years. Thymoma was present in one of the ten patients. We considered that complete thymectomy was accomplished in all cases by examination of the thymic bed and of the resected specimen. There was no mortality or intraoperative complications. The median postoperative hospital stay was 4 days. Clinical improvement was observed in all patients after this short follow-up. Compared with a similar historical group of patients with MG who underwent transsternal thymectomy, the VATS group was associated with significantly less analgesic requirement and shortened hospital stay. We conclude that VAT thymectomy is technically feasible and is associated with a favorable postoperative course compared with the transsternal approach. We believe that complete thymectomy can be achieved by this approach. Further investigation with long-term follow-up is needed to further clarify the role of VAT thymectomy in thoracic surgery.     

Malignancy of familial adenomatous polyposis. Diagnosis and treatment

Familial adenomatous polyposis with features of malignancy find in a 23 years old patient, whose diagnosis has been established on endoscopical basis. Total proctocolectomy is performed with terminal ileostomy. Histopathologically, the diagnosis is revealed, with establishing of multiple areas of malignancy in rectum and sigmoid colon. In the postoperative period, the patient is treated by pelvic radiotherapy and polychemotherapy. After one year, the clinical outcome is good, with weight gain 13 Kg and finishing high school. After two years, peritoneal carcinomatosis and one lung metastasis.     

A single-bout of Endurance Exercise Modulates EEG Microstates Temporal Features

Electrical neuroimaging is a promising method to explore the spontaneous brain function after physical exercise. The present study aims to investigate the effect of acute physical exercise on the temporal dynamic of the resting brain activity captured by the four conventional map topographies (microstates) described in the literature, and to associate these brain changes with the post-exercise neuromuscular function. Twenty endurance-trained subjects performed a 30-min biking task at 60% of their maximal aerobic power followed by a 10 km all-out time trial. Before and after each exercise, knee-extensor neuromuscular function and resting EEG were collected. Both exercises resulted in a similar increase in microstate class C stability and duration, as well as an increase in transition probability of moving toward microstate class C. After the first exercise, the increase in class C global explained variance was correlated with the indice of muscle alterations (100 Hz paired stimuli). After the second exercise, the increase in class C mean duration was correlated with the 100 Hz paired stimuli, but also with the reduction in maximal voluntary force. Interestingly, microstate class C has been associated with the salience resting-state network, which participates in integrating multisensory modalities. We speculate that temporal reorganization of the brain state after exercise could be partially modulated by the muscle afferents that project into the salience resting-state network, and indirectly participates in modulating the motor behavior.     

Similitudes and differences in the reactivity of the liver cell chromatin to thioacetamide and hydrocortisone. Electron microscopic and cytochemical quantitative data concerning the chromatin condensation-dispersion cycle

The administration of thioacetamide (TAA) and/or hydrocortisone to rats brought about dispersion of the heterochromatin in the liver cell, and concomitant stimulation of RNA synthesis in the chromatin. In contrast to other experimental situations in which dispersion of the chromatin persisted for at least 6 hours, after TAA injection dispersion was followed by rapid excess condensation. A hypothesis is suggested concerning the process of induction of malignant proliferation by TAA.