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Copyright of Revista Eletrônica de Materiais e Processos is the property of Revista Eletronica de Materiaia e Processos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Eletrônica de Materiais e Processos is the property of Revista Eletronica de Materiaia e Processos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Eletrônica de Materiais e Processos is the property of Revista Eletronica de Materiaia e Processos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Eletrônica de Materiais e Processos is the property of Revista Eletronica de Materiaia e Processos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Eletrônica de Materiais e Processos is the property of Revista Eletronica de Materiaia e Processos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses research concerning how polycarbonate (PC) is affected by photodegradation on environmental stress cracking resistance of the polymer. Injection molded samples were exposed to ultraviolet (UV) light for differing amounts of time before solvent contact. The bars were subsequently stressed with two separate loads within a tensile testing machine under the presence of ethanol in an attempt to monitor stress relaxation. Additional tests were performed through UV-visible spectroscopy, size exclusion chromatography, light microscopy, and scanning electron microscopy. Results of these tests found that ethanol causes substantial modification in PC, including large-scale surface crazing and reduction in mechanical properties.

Abstract Background Harpalycin 2 (HP-2) is an isoflavone isolated from the leaves of Harpalyce brasiliana Benth., a snakeroot found in northeast region of Brazil and used in folk medicine to treat snakebite. Its leaves are said to be anti-inflammatory. Secretory phospholipases A2 are important toxins found in snake venom and are structurally related to those found in inflammatory conditions in mammals, as in arthritis and atherosclerosis, and for this reason can be valuable tools for searching new anti-phospholipase A2 drugs. Methods HP-2 and piratoxin-III (PrTX-III) were purified through chromatographic techniques. The effect of HP-2 in the enzymatic activity of PrTX-III was carried out using 4-nitro-3-octanoyloxy-benzoic acid as the substrate. PrTX-III induced platelet aggregation was inhibited by HP-2 when compared to aristolochic acid and p-bromophenacyl bromide (p-BPB). In an attempt to elucidate how HP-2 interacts with PrTX-III, mass spectrometry, circular dichroism and intrinsic fluorescence analysis were performed. Docking scores of the ligands (HP-2, aristolochic acid and p-BPB) using PrTX-III as target were also calculated. Results HP-2 inhibited the enzymatic activity of PrTX-III (IC50 11.34 ± 0.28 μg/mL) although it did not form a stable chemical complex in the active site, since mass spectrometry measurements showed no difference between native (13,837.34 Da) and HP-2 treated PrTX-III (13,856.12 Da). A structural analysis of PrTX-III after treatment with HP-2 showed a decrease in dimerization and a slight protein unfolding. In the platelet aggregation assay, HP-2 previously incubated with PrTX-III inhibited the aggregation when compared with untreated protein. PrTX-III chemical treated with aristolochic acid and p-BPB, two standard PLA2 inhibitors, showed low inhibitory effects when compared with the HP-2 treatment. Docking scores corroborated these results, showing higher affinity of HP-2 for the PrTX-III target (PDB code: 1GMZ) than aristolochic acid and p-BPB. HP-2 previous incubated with the platelets inhibits the aggregation induced by untreated PrTX-III as well as arachidonic acid. Conclusion HP-2 changes the structure of PrTX-III, inhibiting the enzymatic activity of this enzyme. In addition, PrTX-III platelet aggregant activity was inhibited by treatment with HP-2, p-BPB and aristolochic acid, and these results were corroborated by docking scores.

This study aimed to analyze the perceptions of obstetricians and gynecology-obstetrics residents at a federal school maternity hospital regarding legal abortion in cases of sexual violence pregnancy, understand their motivations, strengths, and feelings, and identify their experience with this topic. The first stage consisted of answering a self-administered questionnaire. The selection criteria were: obstetricians linked to the obstetric center, director of the medical division, and residents of the institution's obstetrics-gynecology program. In total, 36 questionnaires were answered and returned. The second stage corresponded to an interview using a saturation sampling criterion. Six physicians were interviewed. The interviews were evaluated using a thematic content analysis. The questionnaires showed that all participants had already provided care to women in situations of sexual violence and that most of them had already participated in a legal abortion procedure in these cases. The interviews highlighted the dilemmas faced by professionals in providing care to these women and the lack of professional training to handle these cases. The speeches of women were sometimes seen as an object of suspicion regarding the veracity of sexual violence, and sometimes as an object that caused professionals to feel emotionally affected while listening to them, allowing professionals to approach the victims and offer more humanized care. The results pointed to the importance of addressing this topic in the areas of health and providing training beyond the technical-scientific focus in order to support the development of new care strategies.

Schistosomiasis is an endemic disease in Brazil. It is important to broaden the treatment options to control and containment of the disease. Thiazolidine derivatives appear as important alternatives to treatment. In vitro studies have demonstrated excellent schistosomiasis activity for LPSF/GQ-238. The molecule, however, has poorly water-soluble. This study focused on increasing the aqueous solubility of LPSF/GQ-238 by obtaining solid dispersions. Were prepared by the solvent techniques, using Soluplus®, Polyethylene glycol (PEG), and Polyvinylpyrrolidone (PVP-K30) as carriers. Solubility tests, Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Exploratory Differential Calorimetry (DSC), and Raman Spectroscopy characterized these new intermediate products. The solubility tests showed that the higher the proportion of polymer used in the preparation of the dispersion, the greater the solubility presented. The observation of the morphology by SEM analysis, elucidated, that the new chemical entity (NCE) has a characteristic crystalline structure. The folding of this structure by the polymer was observed in all analyzed dispersions, thus demonstrating the amorphous state of the product. The scales observed in the structures of the dispersions demonstrate the successive wrinkles that occurred. The greater the proportion of the polymer, the greater the number of folds that occurred, which may explain the greater solubility observed in these preparations. The X-ray diffraction profile of the NCE reveals the presence of intense peaks, presenting a crystalline pattern. The polymer, on the other hand, shows amorphous nature, evidenced by the absence of peaks. All the analyzed dispersions did not present the characteristic peaks of the NCE, evidencing the amorphous behavior of the products. The thermal degradation profile of the NCE presents a characteristic crystalline structure endothermic peak. This peak was not observed in any of the obtained dispersions, evidencing the obtaining of a new solid state. Raman spectroscopy showed that peaks in the range 200-400 (cm-1) by NCE were lost when compared to all analyzed dispersions, showing a slight change in the structure of the molecule when dispersed, probably due to the formation of hydrogen bonds with the polymer. The in vitro study showed a significant improvement in the activity of the NCE against the adult worm and to the schistosomulae. It was possible to observe that the obtained solid dispersions were physicochemically and biologically viable for schistosomicidal treatment due to the increase of solubility of the molecule., (Copyright © 2022. Published by Elsevier Inc.)

The Committee for Infections in Immunocompromised Children of Sociedad Latinoamericana de Infectología Pediátrica, presents this Consensus document, titled "Management of episodes of febrile neutropenia in children with cancer. Consensus of the Sociedad Latinoamericana de Infectología Pediátrica 2021". The document includes recommendations on prevention, prediction, diagnosis, treatment and prognosis of episodes of fever and neutropenia, including specific recommendations on: Analysis at admission; evaluation, adjustments and duration of antimicrobial therapies; diagnosis and management of invasive fungal infection; analysis of the main clinical source of infections; environmental conditions necessary for hospitals caring for children with cancer and chemoprophylaxis. Special emphasis has been placed on providing the best recommendations to optimize the management of episodes of fever and neutropenia in children with cancer, with equity and excellence through all the centers that treat these patients in Latin America.

Different carriers, such as the combination of sodium alginate and inulin, have been employed to protect foods against environmental effects. The goal of this work was to use the ionic gelation encapsulation process to produce microparticles containing Clidemia rubra extract, ranging the concentration of inulin from 1.5 to 3.5 g inulin.100 g -1 of solution. Characteristic signals of sugars, organic acids and phenolic compounds were identified in the extract using the 1 H NMR technique. The carriers containing inulin presented significant difference in the moisture content when compared to the pure sodium alginate beads. The produced beads were found in the range of 0.81-1.06 mm. The addition of inulin to sodium alginate was significant for the encapsulation efficiency (EE) of the antioxidant compounds when compared to the beads formed only using pure sodium alginate. The microspheres presenting inulin and sodium alginate presented higher content of spherical particles. The addition of 2.5 g inulin.100 g -1 of solution allowed its incorporation into the pores of the beads, favoring a possible chemical interaction between inulin and sodium alginate. This interaction resulted in a different crystal structure and better EE. Furthermore, beads containing inulin presented higher protection of the encapsulated bioactive compounds during the gastric phase., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Invasive fungal disease is a major cause of morbidity and mortality in children with cancer and high-risk febrile neutropenia (HRFN). Repeated serum galactomannan (sGM) measurements have been described as an effective tool to guide therapy in adults under suspicion of invasive aspergillosis. However, the utility of this approach has not been reported in paediatric population., Objectives: To evaluate the usefulness of sGM measurements in initiating and modifying antifungal therapy (AFT) in children with cancer and persistent HRFN., Patients/methods: Nested case-control study in children with cancer and persistent HRFN episodes, between July 2013 and January 2019. Patients were classified as cases and controls depending on if they received AFT or not, respectively. Through odds ratio analysis, we assessed the role of sGM positivity in the AFT initiation decision. Then, we analysed the group of patients that initiated AFT, and compared those who had AFT modifications and those who did not, analysing different sGM kinetics thresholds., Results: A total of 191 episodes from children with persistent HRFN were enrolled, of which 107 received AFT and 84 did not. The median age was 7 years (IQR 4-12), 52% were male and 89% had a haematologic malignancy as underlying disease. Positive sGM was not associated with AFT initiation (OR 0.99, 95% CI 0.43-2.33, P = .99). A difference threshold in sGM Δ ≥ 0.3 sGM was significantly associated with AFT modification (OR 5.07, 95% CI 1.02- 25.70, P = .04)., Conclusions: Our results suggest the utility of serial sGM sampling during AFT in children with persistent HRFN., (© 2020 Blackwell Verlag GmbH.)

The episodes of febrile neutropenia are severe cases that require an exhaustive etiological study and a quick start of antimicrobial agents. Within the possible microorganisms, fungal origins are also found, and depending on its tissue invasion, they can reach a high mortality rate. A case of a pediatric patient who suffered from acute myeloid leukemia is reported, and after his induction chemotherapy, the patient showed an episode of febrile neutropenia, which matches a rhinosinusal infection caused by Exserohilum rostratum, a filamentous fungi that is uncommonly associated with pathological cases. An antifungal therapy and an early surgical treatment were started, which lead to a positive response, without complications to the patient. After the monitoring and receiving secondary prophylaxis during the episodes of neutropenia, the patient hasn't presented new injuries nor rhinosinusal damage.

Fourteen arylsemicarbazone derivatives were synthesized and evaluated in order to find agents with potential anticancer activity. Cytotoxic screening was performed against K562, HL-60, MOLT-4, HEp-2, NCI-H292, HT-29 and MCF-7 tumor cell lines. Compounds 3c and 4a were active against the tested cancer cell lines, being more cytotoxic for the HL-60 cell line with IC 50 values of 13.08 μM and 11.38 μM, respectively. Regarding the protein kinase inhibition assay, 3c inhibited seven different kinases and 4a strongly inhibited the CK1δ/ε kinase. The studied kinases are involved in several cellular functions such as proliferation, migration, cell death and cell cycle progression. Additional analysis by flow cytometry revealed that 3c and 4a caused depolarization of the mitochondrial membrane, suggesting apoptosis mediated by the intrinsic pathway. Compound 3 c induced arrest in G1 phase of the cell cycle on HL-60 cells, and in the annexin V assay approximately 50% of cells were in apoptosis at the highest concentration tested (26 μM). Compound 4a inhibited cell cycle by accumulation of abnormal postmitotic cells at G1 phase and induced DNA fragmentation at the highest concentration (22 μM).

The use of biological therapies has meant a great improvement in the management of several conditions like autoimmune, neoplastic or others diseases. Although its use has implied significant improvements in the prognosis of these diseases, it is not exempt from complications: infectious diseases as one of them. The objective of this consensus was to evaluate, from an infectious viewpoint, the safeness of the most frequently used biological therapies and give recommendations for the prevention of infections in patients treated with these drugs. These recommendations were based on the highest quality evidence available for the selected biologics. The consensus counts of two manuscripts. This first part details the risks of developing infectious complications depending on the type of biological used for a certain pathology. This evaluation included a broad search in MEDLINE and Epistemonikos of systematic reviews and meta-analyzes of controlled clinical trials and casecontrol examining post-treatment infections with anti-TNF alpha, anti-CD20, anti-CD52, CTLA4-Ig and anti-integrins. The research was complemented by a review of: multicentre cohorts of biological users, the MMWR of the CDC, Atlanta, U.S.A., and national registers and scientific societies in which infectious complications derived from the use of biological therapies were mentioned.

The use of biological therapies has meant a great improvement in the management of several conditions like autoimmune, neoplastic or others diseases. Although its use has implied significant improvements in the prognosis of these diseases, it is not exempt from complications: infectious diseases as one of them. The objective of this consensus was to evaluate, from an infectious viewpoint, the safeness of the most frequently used biological therapies and give recommendations for the prevention of infections in patients treated with these drugs. These recommendations were based on the highest quality evidence available for the selected biologics. The consensus counts of 2 manuscripts. This second part is a guideline that details these recommendations through screening strategies, prophylactic therapies and vaccines indications for bacterial, mycobacterial, viral, fungal and parasitic infections, both for adults and children.

The care of cancer patients, including recipients of hematopoietic stem cell transplantation, has numerous challenges for hospitals that must provide safe environments in which exposure to pathogens that generate morbidity and mortality is reduced at maximum. At the same time, they must have established protocols that allow a rational study of the possible infectious etiologies and the existence of an adequate therapeutic arsenal together with timely treatment algorithms, updated according to consensus guidelines and effective according to the suspected or confirmed infection. This article introduces some of the arguments that support these requirements, then that are developed in three successive articles dedicated to the hospital environment, diagnostic protocols and therapeutic arsenal.

The hospital environment is a potential source of exposure to pathogens such as bacteria, fungi and parasites that can cause infections in patients with cancer including transplanted hematopoietic precursors. To mitigate this risk, the design, construction and location elements of the patient care area must be taken into account. Recommendations are given to provide safe environments, including aspects related to characteristics and use of a protected environment, the definition of critical processes, clinical teams dedicated to the care of patients, suggestions of areas to be monitored, the microbiological quality of air and water.

Background: Active surveillance is necessary for improving the management and outcome of patients with candidemia. The aim of this study was to describe epidemiologic and clinical features of candidemia in children and adults in tertiary level hospitals in Chile., Methods: We conducted a prospective, multicenter, laboratory-based survey study of candidemia in 26 tertiary care hospitals in Chile, from January 2013 to October 2017., Results: A total of 780 episodes of candidemia were included, with a median incidence of 0.47/1,000 admissions. Demographic, clinical and microbiological information of 384 cases of candidemia, from 18 hospitals (7,416 beds), was included in this report. One hundred and thirty-four episodes (35%) occurred in pediatric patients and 250 (65%) in adult population. Candida albicans (39%), Candida parapsilosis (30%) and Candida glabrata (10%) were the leading species, with a significant difference in the distribution of species between ages. The use of central venous catheter and antibiotics were the most frequent risk factors in all age groups (> 70%). Three hundred and fifteen strains were studied for antifungal susceptibility; 21 strains (6.6%) were resistant to fluconazole, itraconazole, voriconazole, anidulafungin or micafungin. The most commonly used antifungal therapies were fluconazole (39%) and echinocandins (36%). The overall 30-day survival was 74.2%, significantly higher in infants (82%) and children (86%) compared with neonates (72%), adults (71%) and elderly (70%)., Conclusions: Our prospective, multicenter surveillance study showed a low incidence of candidemia in Chile, with high 30-day survival, a large proportion of elderly patients, C. glabrata as the third most commonly identified strain, a 6.6% resistance to antifungal agents and a frequent use of echinocandins., Competing Interests: This study was partially supported by an independent medical grant from Pfizer Chile and from BioMerieux Chile. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Background: Helicobacter pylori, the main cause of peptic ulcer disease and gastric cancer in adult populations, is generally acquired during the first years of life. Infection can be persistent or transient and bacterial and host factors determining persistence are largely unknown and may prove relevant for future disease., Methods: Two cohorts of healthy Chilean infants (313 total) were evaluated every 3 months for 18-57 months to determine pathogen- and host-factors associated with persistent and transient infection., Results: One-third had at least one positive stool ELISA by age 3, with 20% overall persistence. Persistent infections were acquired at an earlier age, associated with more household members, decreased duration of breastfeeding, and nonsecretor status compared to transient infections. The cagA positive strains were more common in persistent stools, and nearly 60% of fully characterized persistent stool samples amplified cagA/vacAs1m1. Persistent children were more likely to elicit a serologic immune response, and both infection groups had differential gene expression profiles, including genes associated with cancer suppression when compared to healthy controls., Conclusions: These results indicate that persistent H. pylori infections acquired early in life are associated with specific host and/or strain profiles possibly associated with future disease occurrence., (© The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Introduction: Prolonged febrile syndrome (PFS) is defined as fever 7-10 days, with initial study does not allow etiologic diagnosis., Objective: To describe the main causes of the PFS and its temporal behavior in Pediatric Infectious Diseases Unit Outpatient Care of Complejo Asistencial Dr. Sótero del Río (CASR)., Patients and Methods: A descriptive, prospective study between january 2007-december 2012, about 153 patients from 6 weeks to 14 years 11 months old, diagnosed with PFS, tab completing clinical and laboratory monitoring., Results: etiology was obtained in 67.9%, the causes were infection (88.4%), neoplasms (4.8%), rheumatological (4.8%) and Kawasaki disease (2.8%). The most important infectious causes were enteric fevers (typhoid and paratyphoid) (18.4%), urinary tract infection (11.9%), Bartonella henselae infections and adenovirus (8.7%) each one and Epstein Barr virus (7.6%). Ninety eight percent of patients had complete resolution, 60.7% did not require hospitalization and mortality was 0%., Discussion: As in previous pediatric clinical series the infections were the most frequent causes. Enteric fever persists as principal cause, however, the epidemiological evidence is oscillating in time endorsing the local statistics can count over the years to improve the diagnostic and therapeutic approach.

Background: : Helicobacter pylori colonization/infection can be transitory or persistent, conditions that have not been thoroughly evaluated in young children. We aimed to characterize the dynamics of H. pylori stool detection and to determine host and environmental factors and symptoms associated with persistence., Method: : In a 5-year cohort study, we followed-up infants from birth with clinic visits every 3 months. Symptoms and environmental risk factor survey and a stool sample for H. pylori antigen detection were requested in every visit. Secretor/ABH histo-blood group phenotype was determined in saliva., Results: : Overall, 218 of 1456 (15%) stool samples were positive for H. pylori and 39 of 96 (41%) children had at least 1 positive sample. Stool detection was transitory in 16 of 39 (41%), persistent in 19 (49%) and undetermined in 4 (10%) children. Persistence was acquired largely during the first 24 months (17/19 cases) and was associated with nonsecretor phenotype (32% versus 0% for transitory infection; P = 0.02) and daycare attendance (67% versus 26% for never infected; P = 0.019). Symptoms possibly associated with persistence were referred in only 1 child., Conclusions: : Nearly 20% of this Chilean cohort had persistent H. pylori stool sample detections during the first 5 years of life, acquired mostly during the first 24 months. Persistence was significantly associated with nonsecretor phenotype and daycare attendance, and possibly associated gastrointestinal symptoms were rare. This relatively common group of young children with persistent H. pylori colonization/infection will require further study.

Background: Rotavirus and more recently norovirus have been recognized as 2 of the most common causes of acute diarrhea in children. Comparative analysis of these infections in a birth cohort has not been performed and can provide relevant insight on clinical and viral behaviors., Methods: Mother-infant pairs from middle-low socioeconomic background living in the Metropolitan Region of Chile are being followed for 18 months in 2 outpatient clinics. Infants are evaluated monthly for asymptomatic excretion of rotavirus and norovirus and during acute diarrhea episodes (ADE) for rotavirus, norovirus, and bacterial enteropathogens. Severity of ADE is evaluated using the Vesikari score., Results: Between July 1, 2006 and September 1, 2008 a total of 198 children were followed for a mean of 15.7 months. Asymptomatic rotavirus and norovirus infections were detected in 1.3% and 8% of 2278 stool samples compromising 14% and 57% of infants, respectively. Incidence of ADE was approximately 0.8 for the first year of life and approximately 0.6 for the 13 to 18 month age group. Rotavirus and norovirus were detected in 15% and 18% of 145 ADE evaluated. Mean Vesikari score was 10.4 and 7.4 for rotavirus and norovirus respectively (P = 0.01) and severity was not associated with age of patients for either virus. Reinfections were more common for norovirus asymptomatic episodes: 44% versus 19% (P = 0.01) and borderline for symptomatic episodes: 40% versus 11% (P = 0.08). Rotavirus genotype G9P8 and norovirus genogroup II (GII) predominated although most asymptomatic episodes for both viruses were nontypable. None of 19 symptomatic GII norovirus infections had a previous documented GII infection compared with 10 of 31 asymptomatic GII infections (OR = 0. 95% CL = 0, 0.59; P = 0.008)., Conclusions: Children had suffered a mean of approximately 1.4 ADE by 18 months of age of which 15% and 18% were caused by rotavirus and norovirus, respectively. In general rotavirus infections were more severe than norovirus infections and for both viruses severity was not related to age. Norovirus reinfections were significantly more common than rotavirus reinfections but for GII norovirus a primary infection seems to confer protection against clinically significant reinfections.