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Infections caused by Staphylococcus aureus are a leading cause of mortality worldwide. S. aureus infections caused by methicillin-resistant Staphylococcus aureus (MRSA) are particularly difficult to treat due to their resistance to next-generation β-lactams (NGBs) such as methicillin, nafcillin, and oxacillin. Resistance to NGBs, which is alternatively known as broad-spectrum β-lactam resistance, is classically mediated by PBP2a, a penicillin-binding protein encoded by mecA (or mecC ) in MRSA. Thus, presence of mec genes among S. aureus spp. serves as the predictor of resistance to NGBs and facilitates determination of the proper therapeutic strategy for a staphylococcal infection. Although far less appreciated, mecA -deficient S. aureus strains can also exhibit NGB resistance. These strains, which are collectively termed as methicillin-resistant lacking mec (MRLM), are currently being identified in increasing numbers among natural resistant isolates of S. aureus . The mechanism/s through which MRLMs produce resistance to NGBs remains unknown. In this study, we demonstrate that mutations that alter PBP4 and GdpP functions, which are often present among MRLMs, can synergistically mediate resistance to NGBs. Furthermore, our results unravel that this novel mechanism potentially enables MRLMs to produce resistance toward NGBs at levels comparable to those of MRSAs. Our study provides a fresh new perspective about alternative mechanisms of NGB resistance, challenging our current overall understanding of high-level, broad-spectrum β-lactam resistance in S. aureus . It thus suggests reconsideration of the current approach toward diagnosis and treatment of β-lactam-resistant S. aureus infections., Importance: In Staphylococcus aureus , high-level, broad-spectrum resistance to β-lactams such as methicillin, also referred to as methicillin resistance, is largely attributed to mecA . This study demonstrates that S. aureus strains that lack mecA but contain mutations that functionally alter PBP4 and GdpP can also mediate high-level, broad-spectrum resistance to β-lactams. Resistance brought about by the synergistic action of functionally altered PBP4 and GdpP was phenotypically comparable to that displayed by mecA , as seen by increased bacterial survival in the presence of β-lactams. An analysis of mutations detected in naturally isolated strains of S. aureus revealed that a significant proportion of them had similar pbp4 and G GDEF d omain p rotein containing p hosphodiesterase ( gdpP ) mutations, making this study clinically significant. This study not only identifies important players of non-classical mechanisms of β-lactam resistance but also indicates reconsideration of current clinical diagnosis and treatment protocols of S. aureus infections., Competing Interests: The authors declare no conflict of interest.

For decades, cells of the Gram-positive bacterial pathogen Staphylococcus aureus were thought to lack a dedicated elongation machinery. However, S. aureus cells were recently shown to elongate before division, in a process that requires a shape elongation division and sporulation (SEDS)/penicillin-binding protein (PBP) pair for peptidoglycan synthesis, consisting of the glycosyltransferase RodA and the transpeptidase PBP3. In ovococci and rod-shaped bacteria, the elongation machinery, or elongasome, is composed of various proteins besides a dedicated SEDS/PBP pair. To identify proteins required for S. aureus elongation, we screened the Nebraska Transposon Mutant Library, which contains transposon mutants in virtually all non-essential staphylococcal genes, for mutants with modified cell shape. We confirmed the roles of RodA/PBP3 in S. aureus elongation and identified GpsB, SsaA, and RodZ as additional proteins involved in this process. The gpsB mutant showed the strongest phenotype, mediated by the partial delocalization from the division septum of PBP2 and PBP4, two penicillin-binding proteins that synthesize and cross-link peptidoglycan. Increased levels of these PBPs at the cell periphery versus the septum result in higher levels of peptidoglycan insertion/crosslinking throughout the entire cell, possibly overriding the RodA/PBP3-mediated peptidoglycan synthesis at the outer edge of the septum and/or increasing stiffness of the peripheral wall, impairing elongation. Consequently, in the absence of GpsB, S. aureus cells become more spherical. We propose that GpsB has a role in the spatio-temporal regulation of PBP2 and PBP4 at the septum versus cell periphery, contributing to the maintenance of the correct cell morphology in S. aureus ., Importance: Staphylococcus aureus is a Gram-positive clinical pathogen, which is currently the second cause of death by antibiotic-resistant infections worldwide. For decades, S. aureus cells were thought to be spherical and lack the ability to undergo elongation. However, super-resolution microscopy techniques allowed us to observe the minor morphological changes that occur during the cell cycle of this pathogen, including cell elongation. S. aureus elongation is not required for normal growth in laboratory conditions. However, it seems to be essential in the context of some infections, such as osteomyelitis, during which S. aureus cells apparently elongate to invade small channels in the bones. In this work, we uncovered new determinants required for S. aureus cell elongation. In particular, we show that GpsB has an important role in the spatio-temporal regulation of PBP2 and PBP4, two proteins involved in peptidoglycan synthesis, contributing to the maintenance of the correct cell morphology in S. aureus ., Competing Interests: The authors declare no conflict of interest.

Unregulated cell cycle progression may have lethal consequences and therefore, bacteria have various mechanisms in place for the precise spatiotemporal control of cell cycle events. We have uncovered a new link between chromosome replication/segregation and splitting of the division septum. We show that the DNA translocase domain-containing divisome protein FtsK regulates cellular levels of a peptidoglycan hydrolase Sle1, which is involved in cell separation in the bacterial pathogen Staphylococcus aureus. FtsK interacts with a chaperone (trigger factor, TF) and establishes a FtsK-dependent TF concentration gradient that is higher in the septal region. Trigger factor binds Sle1 and promotes its preferential export at the septal region, while also preventing Sle1 degradation by the ClpXP proteolytic machinery. Upon conditions that lead to paused septum synthesis, such as DNA damage or impaired DNA replication/segregation, TF gradient is dissipated and Sle1 levels are reduced, thus halting premature septum splitting., (© 2023 The Authors. Published under the terms of the CC BY NC ND 4.0 license.)

Parents are required to make various decisions after a child's hearing loss diagnosis. With that in mind, one of the researchers of this study, the father of a child with deaf, did not find any available instrument in the Brazilian literature to support was found to the decision-making process for parents. Considering the importance of assisting parents, caretakers, and professionals who work with Deaf and Hard of Hearing children to monitor and assess the child's development, this work aims to translate and adapt a monitoring protocol for professionals and parents. For this, we translated and cross-culturally adapted 452 items of the Early Support instrument. The items corresponded to the domains of communication, attention, listening, and vocalization. We selected 25% of the items to be assessed by specialists, which were divided into the categories: (1) cultural adequacy; (2) concept presented; and (3) target audience adequacy. A reverse translation was conducted in this stage of the research. After compiling the data and correcting the probable translation errors, it was possible to analyze the items that were not included in the specialists' assessment and propose an assessment with new items. Afterward, the translated items were compared with the reviewed version of the instrument (Success From the Start), which comprises 347 items of the two development domains., (© The Author(s) 2022. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Cryopyrin-associated periodic syndromes (CAPS) are a group of autoinflammatory diseases associated with NLRP3 gain of function mutations. CAPS associated mutations are found predominantly in exon 3. The objective of this study is to describe a new variant on NRLP3 gene and its phenotype. Case report description of a new NRLP3 pathogenic variant and literature case-based search through INFEVERS database. A 21-year old male who presented multiple tonic-clonic seizures on his 3rd day of life. At age 2, he had recurrent central facial palsy, high fever (40 °C), painful and persistent oral ulcers, abdominal pain, nausea and vomiting, and delayed neuropsychomotor development, with polyarthritis in wrists and knees. Over the years, several symptoms were observed: livedo reticularis, Raynaud's phenomenon, positive pathergy test, heat allodynia, extremely painful genital ulcers, and sporadic conjunctivitis. Laboratory studies revealed persistently elevated inflammatory markers and serum amyloid protein A (30 μg/l). The genetic panel for autoinflammatory diseases revealed heterozygous mutation in the NLRP3, (c.2068G > C, p.E690Q) with 0% of frequency in the general population. The patient denies rash and did not have frontal bossing or patellar overgrowth. We found a positive familial history on mother and brother, who carried the same mutation. The patient was started on canakinumab which controlled his symptoms. Currently, 241 missense variants in the NLRP3 have been described. We presented a new mutation in exon 3 of the NRLP3 gene in a patient that fulfills clinical criteria for CAPS who had complete clinical response to Canakinumab, supporting the idea that this mutation is pathogenic.

Background: Concerns about the safety and efficacy of vaccines in patients with autoimmune diseases (AID) have led to contradictions and low vaccination coverage in this population, who are at a higher risk of infections, including by human papillomavirus (HPV). Although HPV vaccines have been recommended for immunocompromised patients, there is still a lack of data to support its use for AID patients, such as juvenile dermatomyositis (JDM) patients. The aim of this study was to assess the safety and immunogenicity of the quadrivalent HPV (qHPV) vaccine in a cohort of JDM patients., Methods: JDM patients aged from 9 to 20 years and healthy controls (HC) were enrolled to receive a 3-dose schedule of qHPV vaccine from March/2014 to March/2016. Study visits were performed before the first dose, 1 month after the second and third doses, and 6 months after the third dose. Participants completed a diary of possible adverse events for 14 days following each dose of vaccination (AEFV). Disease activity and current therapy were analyzed at each visit for JDM patients. In addition, serum samples from all participants were collected to test antibody concentrations against HPV16 and 18 at each visit. Participant recruitment was conducted in ten Brazilian centres. From 47 eligible JDM patients and 41 HC, 42 and 35, respectively, completed the 3-dose schedule of the vaccine, given that five JDM patients and two HC had received doses prior to their inclusion in the study., Results: The AEFVs presented by the participants were mild and in general did not differ between JDM and HC groups. No severe AEFVs were related to the vaccination. Disease activity was stable, or even improved during the follow-up. One month after the third dose of the vaccine the JDM group presented seropositivity of 100% for HPV16 and 97% for HPV18, similarly to the HC group, who presented 100% for both serotypes (p = 1.000). Six months after the third dose the seropositivity for the patient group was 94% for both HPV types., Conclusions: The HPV vaccination in this cohort of JDM patients was safe and immunogenic. Since the seropositivity against HPV16 and 18 was very high after the 3-dose schedule, this regimen should be recommended for JDM patients., Trial Registration: Brazilian Clinical Trials Registry, number: RBR-9ypbtf . Registered 20 March 2018 - Retrospectively registered.

Objective: This study aimed to assess the safety and immunogenicity of the quadrivalent human papillomavirus (qHPV) vaccination in childhood-onset systemic lupus erythematosus (cSLE) patients., Methods: Volunteer cSLE patients aged 9-20 years and healthy controls (HC) were enrolled to receive a two- or three-dose qHPV vaccination schedule from March 2014 to March 2016. Study visits were performed before the first dose, one month after the second and third doses and one year after the first dose. In each study visit, disease activity and adverse events following vaccination were analyzed, and a serum sample was collected for testing antibody concentrations. Participant recruitment was conducted in 15 Brazilian paediatric rheumatology units. Of the 256 cSLE patients included, 210 completed the two- or three-dose schedules; 15 had previously received one dose, and 18 had received two doses of the vaccine. The analysis was based on intention-to-treat so that participants who did not complete the entire study protocol were also included., Results: No severe adverse events were related to the vaccination. Disease activity was generally low and remained stable or even improved. The HC presented 100% seropositivity to HPV16 and HPV18, whereas the two- and three-dose cSLE groups presented 93% and 83% versus 97% and 91%, respectively. One year after the first dose, seropositivity of the three-dose cSLE group was 91% to HPV16 and 84% to HPV18., Conclusions: HPV vaccination in cSLE patients is safe and immunogenic. Since the seropositivity to HPV16 and HPV18 was higher for the three-dose schedule group, this regimen should be recommended for cSLE patients.

Objective: This study evaluates melanoma characteristics in the elderly., Methods: A retrospective descriptive analytical study was carried out by reviewing the medical records of patients aged 60 years or older, diagnosed with primary cutaneous melanoma, and treated at Hospital Erasto Gaertner, Curitiba, Paraná, from 2013 to 2017., Results: We studied 139 patients aged 60-98 years (average, 70.3 years) and found melanoma to be more common in women (52.5%) than in men. Lesions mainly affected the limbs (32.3%) and head (24.4%), showed signs of ulceration (33.8%), and could be classified into the nodular histological (29%), extensive superficial (27%), and acral (12%) types. The average Breslow index was 1.2 mm. Metastasis occurred in 33% of the patients and mainly affected lymph nodes (36%) and the central nervous system (CNS, 20%). The first procedure conducted in 79% of the cases was surgical resection. Sentinel node mapping was carried out in 41.7% of the cases, and surgical treatment alone was indicated in 70% of the patients. The disease recurred in 34.5% of the patients, and 17.9% succumbed to the disease. These results indicate that the elderly have poorer prognosis when cancer treatment is delayed., Conclusion: Melanoma of the limbs and head, intermediate Breslow index, metastatic lymph node and CNS metastases, and relapse result in fatal outcomes. Direct strategies, such as prevention and early detection, as well as uniform and adequate treatment, are needed to improve disease management in the elderly.

Lapachol is a plant-derived naphthoquinone that kills several types of cancer cells. Derivatives of this molecule may therefore prove to be useful chemotherapeutic agents. In this study, we explored whether glycosylation increases the cytotoxic potency of lapachol towards HL-60 human leukemia cells. Two beta-glycosides were synthesized and characterized: LA4A (lapachol-β-glucoside) and LA4C (lapachol-N-acetylglucosamine-β-glucoside). The sugar moieties of both novel molecules were per-acetylated to facilitate cellular uptake. The IC 50 values (in μM) for LA4A (5.7) and LA4C (5.3) were lower than those for lapachol (25). LA4A and LA4C triggered typical signs of apoptosis, such as the exposure of phosphatidylserine on the outside of cells, chromatin condensation, DNA fragmentation and a decrease of the mitochondrial transmembrane potential (ΔΨm) prior to cell lysis. Moreover, DNA fragmentation triggered by the lapachol-glycosides was reduced by pre-treatment with the caspase inhibitor, z-VAD-fmk. While LA4A and LA4C activated caspases-3, -8 and -9, lapachol failed to activate these apoptotic proteases, even when used at high concentrations. Finally, the toxicity of lapachol and its derivatives was also tested on non-tumor cells. We used human peripheral neurons (PeriTox test) to evaluate the side effect potential of these compounds. LA4C was clearly less toxic than LA4A. We conclude that LA4C had the most favorable profile as drug candidate (high tumor cell toxicity, reduced neurotoxicity). In general, this study shows that the cytotoxicity of lapachol towards HL-60 can be enhanced by glycosylation, and that the therapeutic ratio may be modified by the type of sugar added., Competing Interests: Declaration of Competing Interest The authors declare that they do not have any conflicts of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In low-income countries, the history of academic failure is a liability for children acquiring literacy skills. It is thus important to develop strategies that motivate and focus these students on specific strategies to learn to read. Digital games can be useful in motivating students and assisting teachers in the teaching-learning process, but there are few interactive tools that effectively integrate tasks of direct instruction and good gameplay. This technical report describes an interactive digital game to engage students in the initial phase of reading skills acquisition, whose design incorporates evidence-based procedures. The game, called "The Adventures of Amaru," aims to promote word coding-decoding skills and vocabulary growth through teaching trials. We discuss the adaptation of reading teaching curricula, their limitations and future implications of the use of this game by children from a low-income background.

Triazoles are interesting templates for novel chemotherapeutic drugs. We synthesized here 17 1,3,4-substituted-1,2,3-triazoles that differed in their 1'-substituent (variable alkyl chain lengths C3-C12), the 3'-substituent (no substituent, -methyl or -propyl) or the salt form obtained. Several of the compounds were cytotoxic (μM range) for tumor cells (HL-60, Jurkat, MCF-7, HCT-116), and when the effect was compared to non-transformed cells (Vero), selectivity ratios of up to 23-fold were obtained. To estimate the liability of these potential drug candidates for triggering neurotoxicity, we used the LUHMES cell-based NeuriTox assay. This test quantifies damage to the neurites of human neurons. The four most potent tumoricidal compounds were found to be neurotoxic in a concentration range similar to the one showing tumor cell toxicity. As the neurites of the LUHMES neurons were affected at >4-fold lower concentrations than the overall cell viability, the novel triazoles were classified as specific neurotoxicants. The structure-activity relationship (SAR) for neurotoxicity was sharply defined and correlated with the one for anti-neoplastic activity. Based on this SAR, two non-neurotoxic compounds were predicted, and testing in the NeuriTox assay confirmed this prediction. In summary, the panel of novel triazoles generated and characterized here, allowed to define structural features associated with cytotoxicity and neurotoxicity. Moreover, the study shows that potential neurotoxic side effects may be predicted early in drug development if highly sensitive test methods for neurite integrity are applied., (Copyright © 2018 Elsevier B.V. All rights reserved.)

N-(2-butanoyloxyethyl)-4-(chloromethyl)-3-nitrobenzamide (NBCN) is a nitroaromatic bioreducible compound with cytotoxic effects in cancer cell lines. The aim of this work was to investigate the molecular mechanisms involved in cell death promoted by NBCN in HL60 cells. We observed that NBCN treatment increased intracellular ROS and reduced mitochondria membrane potential (ΔΨm). NBCN treatment also induced morphological changes, phosphatidylserine exposure, cell cycle arrest in G2/M-phase, DNA condensation and fragmentation, but it did not show cytotoxic effects on normal human peripheral blood mononuclear cells (PBMCs). NBCN-induced caspase 3- and 9-dependent DNA fragmentation, which was blocked by pretreatment with the broad-spectrum caspase inhibitor, z-VAD-fmk. Flow cytometry analysis demonstrated that NBCN also increased of the number of autophagic vesicles in HL60 cells, which was not observed when cells were pre-treated with bafilomycin A1. Taken together, these results indicate that NBCN triggered the mitochondrial apoptotic pathway and led to the onset of autophagic cell death, which contributed to its cytotoxic effects., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This study aimed to further investigate the cytotoxicity against tumor cell lines and several bacterial strains of Annona squamosa and its mode of action. Methanol extracts of A. squamosa leaves (ASL) and seeds (ASS) were used. ASL showed significant antibacterial activity against S. aureus, K. pneumoniae and E. faecalis with MIC values of 78, 78 and 39 µg/mL respectively. Moreover, ASL exhibited significant biofilm disruption, rapid time dependent kinetics of bacterial killing, increased membrane permeability and significantly reduced the cell numbers and viability. Regarding the cytotoxicity against tumor cell lines, ASS was more active against Jurkat and MCF-7 cells, with CI50 1.1 and 2.1 µg/mL, respectively. ASL showed promising activity against Jurkat and HL60, with CI50 4.2 and 6.4 µg/mL, respectively. Both extracts showed lower activity against VERO cells and reduced the clonogenic survival at higher concentrations (IC90) to MCF-7 and HCT-116 lineages. The alkaloids anonaine, asimilobine, corypalmine, liriodenine nornuciferine and reticuline were identified in extracts by UPLC-ESI-MS/MS analysis. This study reinforced that A. squamosa presents a remarkable phytomedicinal potential and revealed that its antimicrobial mechanism of action is related to bacterial membrane destabilization.

Complexes [Bi(2AcPh)Cl2]·0.5H2O (1), [Bi(2AcpClPh)Cl2] (2), [Bi(2AcpNO2Ph)Cl2] (3), [Bi(2AcpOHPh)Cl2]·2H2O (4), [Bi(H2BzPh)Cl3]·2H2O (5), [Bi(H2BzpClPh)Cl3] (6), [Bi(2BzpNO2Ph)Cl2]·2H2O (7) and [Bi(H2BzpOHPh)Cl3]·2H2O (8) were obtained with 2-acetylpyridine phenylhydrazone (H2AcPh), its -para-chloro-phenyl- (H2AcpClPh), -para-nitro-phenyl (H2AcpNO2Ph) and -para-hydroxy-phenyl (H2AcpOHPh) derivatives, as well as with the 2-benzoylpyridine phenylhydrazone analogues (H2BzPh, H2BzpClPh, H2BzpNO2Ph, H2BzpOHPh). Upon coordination to bismuth(III) antibacterial activity against Gram-positive and Gram-negative bacterial strains significantly improved except for complex (4). The cytotoxic effects of the compounds under study were evaluated on HL-60, Jurkat and THP-1 leukemia, and on MCF-7 and HCT-116 solid tumor cells, as well as on non-malignant Vero cells. In general, 2-acetylpyridine-derived hydrazones proved to be more potent and more selective as cytotoxic agents than the corresponding 2-benzoylpyridine-derived counterparts. Exposure of HCT-116 cells to H2AcpClPh, H2AcpNO2Ph and complex (3) led to 99% decrease of the clonogenic survival. The IC50 values of these compounds were three-fold smaller when cells were cultured in soft-agar (3D) than when cells were cultured in monolayer (2D), suggesting that they constitute interesting scaffolds, which should be considered in further studies aiming to develop new drug candidates for the treatment of colon cancer., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

This study verified the prevalence of dental fluorosis in 12-year-old children and its association with different fluoride levels in the public water supply, and evaluated the level of perception of dental fluorosis by the studied children. To assess fluorosis prevalence, clinical examinations were performed and a structured instrument was used to evaluate the self-perception of fluorosis. The water supply source in the children's area of residence since birth was used as the study criterion. In total, 496 children were included in the study. Fluorosis was diagnosed in 292 (58.9%) children; from these, 220 (44.4%) children were diagnosed with very mild fluorosis, 59 (11.9%) with mild fluorosis, 12 (2.4%) with moderate fluorosis, and 1 (0.2%) child with severe fluorosis. A significant association (p = 0.0004) was observed between the presence of fluorosis and areas with excessive fluoride in the water supply. Among the 292 children that showed fluorosis, 40% perceived the presence of spots in their teeth. The prevalence of fluorosis was slightly high, and the mildest levels were the most frequently observed. Although most of the children showed fluorosis to various degrees, the majority did not perceive these spots, suggesting that this alteration did not affect their quality of life.