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Alzheimer’s disease (AD) is the most common type of dementia in the elderly. Several hypotheses emerged from AD pathophysiological mechanisms. However, no neuronal protective or regenerative drug is available nowadays. Researchers still work in drug development and are finding new molecular targets to treat AD. Therefore, this study aimed to summarize main advances in AD pharmacological therapy. Clinical trials registered in the National Library of Medicine database were selected and analyzed accordingly to molecular targets, therapeutic effects, and safety profile. The most common outcome was the lack of efficacy. Only seven trials concluded that tested drugs were safe and induced any kind of therapeutic improvement. Three works showed therapeutic effects followed by toxicity. In addition to aducanumab recent FDA approval, antibodies against amyloid-β (Aβ) showed no noteworthy results. 5-HT6 antagonists, tau inhibitors and nicotinic agonists’ data were discouraging. However, anti-Aβ vaccine, BACE inhibitor and anti-neuroinflammation drugs showed promising results.

Caffeine consumption by academics, especially those in medical school, is done indiscriminately due to the need to reduce fatigue during their activities and, consequently, increasing their performance. Although it seems to be a harmless practice, it can be related to some health problems. Among these other damages are: arrhythmias, urinary incontinence, loss of appetite, nausea, increased blood pressure, insomnia and sudden death. In this context, this work evaluated cardiovascular damage associated to long-term use of caffeine based on clinical evaluation of students aged 18 years or older in a private medical college in Espírito Santo. Analysis was performed through a brief questionnaire followed by assessment of heart rate and blood pressure. The work was performed with 26 men and 69 women and an average of 70% of the population claimed to consume caffeine. It was also seen that among the students who had the greatest changes in relation to blood pressure were those who were in the 1st and 3rd years of the course. In short, no significant changes were observed in relation to caffeine consumption throughout graduation or cardiovascular impacts associated with its use. However, the evaluated individuals are mostly young and the study follow-up time was short.Keywords:Caffeine; Heart rate; Blood pressure; Chronic intoxication

Copper(II) complexes [Cu(H 2 O) 2 (L1)(phen)](ClO 4 ) ( 1 ) and [Cu(H 2 O)(L2)(phen)](ClO 4 ) ( 2 ) (HL1 = naringenin; HL2 = hesperetin) were obtained, in which an anionic flavonoid ligand is attached to the metal center along with 1,10-phenanthroline (phen) as co-ligand. Complexes ( 1 ) and ( 2 ) were assayed for their cytotoxic activity against A549 lung carcinoma and against normal lung fibroblasts (LL-24) and human umbilical vein endothelial cells (HUVEC). We found IC 50  = 16.42 µM ( 1 ) and IC 50  = 5.82 µM ( 2 ) against A549 tumor cells. Complexes ( 1 ) and ( 2 ) exhibited slight specificity, being more cytotoxic against malignant than against non-malignant cells. 1 and 2 induced apoptosis on A549 cells in a mitochondria-independent pathway, and showed antioxidant activity. The antioxidant effect of the complexes could possibly improve their apoptotic action, most likely by a PI3K-independent reduction of autophagy. Complexes ( 1 ) and ( 2 ) interact in vitro with calf thymus DNA by an intercalative binding mode. EPR data indicated that 1 and 2 interact with human serum albumin (HSA) forming mixed ligand species. Graphical abstract

Capsaicin, the primary pungent component of the chili pepper, has antitumor activity. Herein, we describe the activity of RPF151, an alkyl sulfonamide analogue of capsaicin, against MDA-MB-231 breast cancer cells. RPF151 was synthetized, and molecular modeling was used to compare capsaicin and RPF151. Cytotoxicity of RPF151 on MDA-MB-231 was also evaluated by the 3-[4,5-dimethylthiazol-2-yl]-2,5diphenyltetrazolium bromide (MTT) assay. Cell cycle analysis, by flow cytometry, and Western blot analysis of cycle-related proteins were used to evaluate the antiproliferative mechanisms. Apoptosis was evaluated by phosphatidyl-serine externalization, cleavage of Ac-YVAD-AMC, and Bcl-2 expression. The production of reactive oxygen species was evaluated by flow cytometry. RPF151 in vivo antitumor effects were investigated in murine MDA-MB-231 model. This study shows that RPF151 downregulated p21 and cyclins A, D1, and D3, leading to S-phase arrest and apoptosis. Although RPF151 has induced the activation of TRPV-1 and TRAIL-R1/DR4 and TRAIL-2/DR5 on the surface of MDA-MB-231 cells, its in vivo antitumor activity was TRPV-1-independent, thus suggesting that RPF151 should not have the same pungency-based limitation of capsaicin. In silico analysis corroborated the biological findings, showing that RPF151 has physicochemical improvements over capsaicin. Overall, the activity of RPF151 against MDA-MB-231 and its lower pungency suggest that it may have a relevant role in cancer therapy.

Background Lipid nanoparticles (LNP) are a safe and effective messenger RNA (mRNA) delivery system for vaccine applications, as shown by the COVID-19 mRNA vaccines. One of the main challenges faced during the development of these vaccines is the production of new and versatile LNP formulations capable of efficient encapsulation and delivery to cells in vivo. This study aimed to develop a new mRNA vaccine formulation that could potentially be used against existing diseases as well as those caused by pathogens that emerge every year. Results Using firefly luciferase (Luc) as a reporter mRNA, we evaluated the physical–chemical properties, stability, and biodistribution of an LNP-mRNA formulation produced using a novel lipid composition and a microfluidic organic-aqueous precipitation method. Using mRNAs encoding a dengue virus or a Leishmania infantum antigen, we evaluated the immunogenicity of LNP-mRNA formulations and compared them with the immunization with the corresponding recombinant protein or plasmid-encoded antigens. For all tested LNP-mRNAs, mRNA encapsulation efficiency was higher than 85%, their diameter was around 100 nm, and their polydispersity index was less than 0.3. Following an intramuscular injection of 10 µg of the LNP-Luc formulation in mice, we detected luciferase activity in the injection site, as well as in the liver and spleen, as early as 6 h post-administration. LNPs containing mRNA encoding virus and parasite antigens were highly immunogenic, as shown by levels of antigen-specific IgG antibody as well as IFN-γ production by splenocytes of immunized animals that were similar to the levels that resulted from immunization with the corresponding recombinant protein or plasmid DNA. Conclusions Altogether, these results indicate that these novel LNP-mRNA formulations are highly immunogenic and may be used as novel vaccine candidates for different infectious diseases. Graphical Abstract

Previous studies have indicated that antibody responses can be robustly induced after the vaccination in individuals previously infected by SARS-CoV-2. To evaluate anti-SARS-CoV-2 humoral responses in vaccinated individuals with or without a previous history of COVID-19, we compared levels of anti-SARS-CoV-2 antibodies in the sera from 21 vaccinees, including COVID-19-recovered or -naïve individuals in different times, before and after immunization with an inactivated COVID-19 vaccine. Anti-SARS-CoV-2-specific antibodies elicited after COVID-19 and/or immunization with an inactivated vaccine were measured by ELISA and Plaque Reduction Neutralizing assays. Antibody kinetics were consistently different between the two vaccine doses for naïve individuals, contrasting with the SARS-CoV-2-recovered subjects in which we observed no additional increase in antibody levels following the second dose. Sera from SARS-CoV2-naïve individuals had no detectable neutralizing activity against lineage B.1 SARS-CoV-2 or Gamma variant five months after the second vaccine dose. Contrarily, SARS-CoV-2-recovered subjects retained considerable neutralizing activity against both viruses. We conclude that a single inactivated SARS-CoV-2 vaccine dose may be sufficient to induce protective antibody responses in individuals with previous history of SARS-CoV-2 infection.

Accurate testing to detect SARS-CoV-2 RNA is key to counteract the virus spread. Nonetheless, the number of diagnostic laboratories able to perform qPCR tests is limited, particularly in developing countries. We describe the use of a virus-inactivating, denaturing solution (DS) to decrease virus infectivity in clinical specimens without affecting RNA integrity. Swab samples were collected from infected patients and from laboratory personnel using a commercially available viral transport solution and the in-house DS. Samples were tested by RT-qPCR, and exposure to infective viruses was also accessed by ELISA. The DS used did not interfere with viral genome detection and was able to maintain RNA integrity for up to 16 days at room temperature. Furthermore, virus loaded onto DS were inactivated, as attested by attempts to grow SARS-CoV-2 in cell monolayers after DS desalt filtration to remove toxic residues. The DS described here provides a strategy to maintain diagnostic accuracy and protects diagnostic laboratory personnel from accidental infection, as it has helped to protect our lab crew.

S. aureus are among the main bacteria causing problems related to multidrug resistance in nosocomial infections. Therefore, it is necessary to carry out a reliable and rapid diagnosis for the identification of the bacteria and characterization of its susceptibility profile, especially vancomycin, which is an alternative treatment against multidrug-resistant (MDR) S. aureus. Thus, the goal of this study was to characterize isolates of S. aureus regarding the resistance and virulence and to check the susceptibility to vancomycin, through different methods, for comparative purposes. Seventeen antimicrobials were tested to assess the susceptibility profile. It was evaluated the presence of identification (nuc), resistance (mecA and blaZ), biofilm (icaA and icaD) and siderophore (sfaD and sbnD) genes. The susceptibility to vancomycin was evaluated by Minimum Inhibitory Concentration (MIC) by broth microdilution (BMD), E-test, commercial panel (Kit), and Phoenix equipment. Most S. aureus (93,33%) was classified as MDR. These isolates were 100% positive for nuc, mecA, icaA, icaD, and sfaD genes; 96.67% for sbnD and 33.33% for blaZ. In relation to BMD, all methods correctly classified the susceptibility of the isolates; however, regarding the exact MIC value for vancomycin, Phoenix showed agreement of 63.33%, E-test (33.33%) and Kit (26.66%). In conclusion, most of S. aureus was considered MDR. Also, they presented resistance, biofilm production, and siderophores genes, showing the pathogenic potential of these bacteria. Besides, the Phoenix test was considered the most effective, as it presents advantages, such as identification of the microorganism and a greater number of antimicrobials tested at a time.

The histamine receptors (HRs) are traditional G protein-coupled receptors of extensive therapeutic interest. Recently, H3R and H4R subtypes have been targeted in drug discovery projects for inflammation, asthma, pain, cancer, Parkinson’s, and Alzheimer’s diseases, which includes searches for dual acting H3R/H4R ligands. In the present work, nine 1-[(2,3-dihydro-1-benzofuran-2-yl)methyl]piperazine (LINS01 series) molecules were synthesized and evaluated as H3R and H4R ligands. Our data show that the N -allyl-substituted compound LINS01004 bears the highest affinity for H3R (p K i 6.40), while the chlorinated compound LINS01007 has moderate affinity for H4R (p K i 6.06). In addition, BRET assays to assess the functional activity of Gi1 coupling indicate that all compounds have no intrinsic activity and act as antagonists of these receptors. Drug-likeness assessment indicated these molecules are promising leads for further improvements. In vivo evaluation of compounds LINS01005 and LINS01007 in a mouse model of asthma showed a better anti-inflammatory activity of LINS01007 (3 g/kg) than the previously tested compound LINS01005. This is the first report with functional data of these compounds in HRs, and our results also show the potential of their applications as anti-inflammatory.

Vaccines are essential for the prevention and control of several diseases, and monitoring the immune response generated by vaccines is crucial. The immune response generated by vaccination against SARS-CoV-2 in children and adolescents is not well defined in terms of the intensity and medium to long-term duration of protective immunity, which may indicate the need for booster doses and could support decisions in public health. The study aims to evaluate the immunogenicity and safety of an inactivated SARS-CoV-2 vaccine (CoronaVac) in a two-dose primary protocol in children and adolescents aged 3 to 17 years old in Brazil. Participants were invited to the research at two public healthcare centers located in Serrana (São Paulo) and Belo Horizonte (Minas Gerais), Brazil. They underwent medical interviews to gather their medical history, including COVID-19 history and medical records. Physical exams were conducted, which included measurements of weight, blood pressure, temperature, and pulse rate. Blood samples were obtained from the participants before vaccination, 1 month after the first dose, and at 1, 3, and 6 months after the second dose. These samples were followed up using a virtual platform to monitor post-vaccination reactions and symptoms of COVID-19. The SARS-CoV-2 genome from swab samples of COVID-19 positive individuals was sequenced using NGS. Total antibodies were measured by ELISA, and neutralizing antibodies to the B.1 lineage and Omicron variant (BA.1) were quantified by PRNT and VNT assays. The cellular immune response was evaluated by flow cytometry through the quantification of systemic soluble immune mediators. The follow-up of 640 participants showed that CoronaVac was able to significantly induce the production of total IgG antibodies to SARS-CoV-2 and the production of neutralizing antibodies to the B.1 lineage and Omicron variant. Additionally, a robust cellular immune response was observed, characterized by a wide release of pro-inflammatory and regulatory mediators in the early post-immunization moments. Adverse events recorded so far have been mild and transient, except for seven serious adverse events reported on VigiMed. The results indicate a robust and sustained immune response induced by CoronaVac in children and adolescents for up to six months, providing evidence to support the safety and immunogenicity of this effective immunizer.