Policies on children and schools during the SARS-CoV-2 pandemic in Western Europe.

During the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), mitigation policies for children have been a topic of considerable uncertainty and debate. Although some children have co-morbidities which increase their risk for severe coronavirus disease (COVID-19), and complications such as multisystem inflammatory syndrome and long COVID, most children only get mild COVID-19. On the other hand, consistent evidence shows that mass mitigation measures had enormous adverse impacts on children. A central question can thus be posed: What amount of mitigation should children bear, in response to a disease that is disproportionally affecting older people? In this review, we analyze the distinct child versus adult epidemiology, policies, mitigation trade-offs and outcomes in children in Western Europe. The highly heterogenous European policies applied to children compared to adults did not lead to significant measurable differences in outcomes. Remarkably, the relative epidemiological importance of transmission from school-age children to other age groups remains uncertain, with current evidence suggesting that schools often follow, rather than lead, community transmission. Important learning points for future pandemics are summarized.

Prospective study of loss of health-related quality adjusted life years in children and their families due to uncomplicated and hospitalised varicella.

INTRODUCTION AND AIMS: Although usually benign, varicella can lead to serious complications and sometimes long-term sequelae. Vaccines are safe and effective but not yet included in immunisation programmes in many countries. We aimed to quantify the impact on health-related quality of life (HRQoL) in terms of quality-adjusted life years (QALY) in children with varicella and their families, key to assessing cost-utility in countries with low mortality due to this infection. METHODS: Children with varicella in the community and admitted to hospitals in Portugal were included over 18 months from January 2019. Children's and carers' HRQoL losses were assessed prospectively using standard multi-attribute utility instruments for measuring HRQoL (EQ-5D and CHU9D), from presentation to recovery, allowing the calculation of QALYs. RESULTS: Among 109 families with children with varicella recruited from attendees at a pediatric emergency service (community arm), the mean HRQoL loss/child was 2.0 days (95 % CI 1.9-2.2, n = 101) (mean 5.4 QALYs/1000 children (95 % CI 5.3-6.1) and 1.3 days/primary carer (95 % CI 1.2-1.6, n = 103) (mean 3.6 QALYs /1000 carers (95 % CI 3.4-4.4). Among 114 families with children admitted to hospital because of severe varicella or a complication (hospital arm), the mean HRQoL loss/child was 9.8 days (95 % CI 9.4-10.6, n = 114) (mean 26.8 QALYs /1000 children (95 % CI 25.8-29.0) and 8.5 days/primary carer (95 % CI 7.4-9.6, n = 114) (mean 23.4 QALYs/1000 carers (95 % CI 20.3-26.2). Mean QALY losses/1000 patients were particularly high for bone and joint infections [67.5 (95 % CI 43.9-97.6)]. Estimates for children's QALYs lost using the CHU9D tool were well correlated with those obtained using EQ-5D, but substantially lower. CONCLUSIONS: The impact of varicella on HRQoL is substantial. We report the first measurements of QALYs lost in hospitalised children and in the families of children both in the community and admitted to hospital, providing important information to guide vaccination policy recommendations.

Electrochemistry of chemotherapeutic alkylating agents and their interaction with DNA.

Alkylating agents were among the first anticancer drugs to be discovered and continue to be the most commonly used in chemotherapy. They are electrophiles that react with the ring nitrogen and extracyclic oxygen atoms of DNA bases, forming covalent adducts that further lead to cross-linking of DNA strands, abnormal base pairing or DNA strand breaks. The investigation and quantitative analysis of alkylating agents in biological samples are essential for monitoring the therapy progression and efficiency, understanding their pharmacokinetics and develop new more effective and specific chemotherapeutical drugs. Among biotechnological methods, electrochemical techniques are particularly important in pharmaceutical medicine, owing to their rapid detection, great sensitivity, robustness, exceptional detection limits, ability to be used with small analyte volumes in turbid biofluids, and easy adaptability to miniaturization and point-of-care (POC) testing. This article provides first an exhaustive review concerning the electrochemical methods of characterization and quantification of different classes of chemotherapeutic alkylating agents (triazenes and hydrazines, nitrosoureas, nitrogen mustards, oxazaphosphorines, alkyl alkane sulfonates and ethylene imines) in standard samples, pharmaceutical formulations and biological matrixes. The second part of the article focuses on the recent electrochemical methodologies and DNA-electrochemical biosensors developed to study the interaction of alkylating agents with DNA. These studies are relevant for obtaining real-time details about the alkylating agents' mechanism of action and for assessing the oxidative DNA damage they cause, important for the development of improved antineoplastic drugs.

Mycoplasma pneumoniae-associated mucositis.

A 9-year-old boy presented to the emergency department of a paediatric hospital with non-painful lesions on his lips and inside his mouth, associated with lip swelling. On examination, his oral mucosa and lips showed numerous blisters with yellowish serofibrinous content and lip oedema. An eye examination revealed bilateral conjunctival injection. Genitalia was unaffected and no other skin lesions were found. He was on day 4 of clarithromycin prescribed for atypical pneumonia caused by Mycoplasma pneumoniae The patient was diagnosed with M. pneumoniae-associated mucositis and was started on topical treatment with fusidic acid and betamethasone, with gradual improvement of the oral lesions.

Parechovirus Genotype 3 Outbreak Among Young Infants in Portugal.

INTRODUCTION: Human parechovirus type 3 has been recognized as a cause of pediatric infection, occasionally associated with serious illness, including sepsis and meningitis, particularly among young infants. The aim of this study is to report the first known human parechovirus type 3 outbreak in Portugal. MATERIAL AND METHODS: Descriptive study of an outbreak that occurred between the 8th June to the 12th August 2016. Laboratory diagnosis was made by reverse transcription - polymerase chain reaction in the cerebrospinal fluid and/or in stools. Genotyping was made by reverse transcription - polymerase chain reaction and sequencing in stool samples from infants and family members. RESULTS: Human parechovirus type 3 infection was detected in seven infants, of which six were male. Median age was 23 days (5 - 52). One had seizures, with a magnetic resonance imaging scan showing white matter diffusion restriction. The mean duration of admission was 5.6 days (3 - 11), with favourable outcome in all. In three cases there were symptomatic close family members. Human parechovirus type 3 was identified in the stools of three mothers. DISCUSSION: Even though human parechovirus type 3 infection has been well described in the presented age group, most Portuguese hospitals do not have this laboratory diagnosis. Our results are comparable to those obtained in other countries. Besides detection of the virus in the cerebrospinal fluid, there were no raised local or systemic inflammatory markers. CONCLUSION: This study reports the first known outbreak, in infants, of human parechovirus type 3 in Portugal. Although there is no specific treatment, this diagnosis can avoid unnecessary empirical antibiotic treatment and prolonged admissions.

Introdução: O parechovirus humano tipo 3 tem sido reconhecido como causa de infeção em idade pediátrica, ocasionalmente associado a doença grave, incluindo sépsis e meningite, particularmente em pequenos lactentes. Foi objectivo deste estudo descrever o primeiro surto conhecido de infeção por parechovirus humano tipo 3 em Portugal. Material e Métodos: Estudo descritivo de um surto ocorrido entre 8 de junho a 12 de agosto de 2016. O diagnóstico laboratorial foi realizado por transcriptase reversa - reação em cadeia da polimerase no líquido cefalorraquidiano e/ou nas fezes. A genotipagem foi efetuada no Instituto Nacional de Saúde Doutor Ricardo Jorge, por transcriptase reversa - reação em cadeia da polimerase e sequenciação, em amostras de fezes dos lactentes e seus familiares. Resultados: Foi detetada infeção por parechovirus humano tipo 3 em sete lactentes, seis dos quais do sexo masculino, mediana de idade de 23 dias (5 - 52). Uma lactente apresentou convulsões, com múltiplas lesões da substância branca na ressonância magnética nuclear. A duração média de internamento foi de 5,6 dias (3 - 11), com evolução favorável em todos. Em três casos havia familiares próximos sintomáticos. Em três mães foi identificado parechovirus humano tipo 3 nas fezes. Discussão: Embora a infeção por parechovirus humano tipo 3 esteja bem descrita neste grupo etário, a maior parte dos hospitais portugueses não dispõe deste diagnóstico laboratorial. Os resultados obtidos foram semelhantes aos verificados noutros países. Apesar da deteção do vírus no líquido cefalorraquidiano, destaca-se a ausência de resposta inflamatória local ou sistémica. Conclusão: Este estudo reporta o primeiro surto conhecido de infeção por parechovirus humano tipo 3 ocorrido em Portugal em pequenos lactentes. Apesar de não existir tratamento específico, este diagnóstico poderá evitar poderá evitar antibioterapia e internamentos prolongados.

Doença de Kawasaki: Preditores de Resistência à Imunoglobulina Intravenosa e Complicações Cardíacas / Kawasaki Disease: Predictors of Resistance to Intravenous Immunoglobulin and Cardiac Complications

Resumo Fundamento: A doença de Kawasaki (DK) é a principal causa de cardiopatia adquirida em idade pediátrica nos países desenvolvidos. Objetivos: Identificar fatores preditores de resistência à imunoglobulina intravenosa (IGIV), calcular a eficácia dos modelos preditores japoneses e caracterizar as complicações cardíacas. Métodos: Análise retrospectiva dos casos de DK entre janeiro de 2006 e julho de 2018 em um hospital pediátrico português. Foram construídas curvas ROC para encontrar fatores preditores de resistência e utilizada regressão logística multivariada para elaborar o modelo preditor. O nível de significância utilizado foi de 5%. Resultados: Foram incluídos 48 pacientes com mediana de idade de 36 meses. Verificou-se resistência à IGIV em 21%. Ocorreram alterações ecocardiográficas em 46%, com envolvimento coronário em 25%. Como variáveis preditoras de resistência, a proteína C-reativa (PC-R) apresentou uma AUC ROC = 0,789, ponto de corte = 15,1 mg/dL, sensibilidade (S) = 77,8% e especificidade (E) = 78,9%. A velocidade de sedimentação (VS) apresentou uma AUC ROC = 0,781, ponto de corte = 90,5 mm/h, S = 66,7% e E = 85,7%. O modelo com as duas variáveis apresentou valor p = 0,042 e AUC ROC = 0,790. O modelo Kobayashi apresentou S = 63,6% e E = 77,3%; Egami, S = 66,7% e E = 73,1%; e Sano, S = 28,6% e E = 94,1%. Conclusão: A PC-R e a VS são variáveis independentes que mostraram tendência preditora de resistência à IGIV com pontos de corte ótimos de 15,1 mg/dL e 90,5 mm/h, respectivamente. Cerca de metade dos pacientes teve algum tipo de envolvimento cardíaco. Os modelos japoneses não têm utilidade nessa população. (Arq Bras Cardiol. 2021; 116(3):485-491)

Abstract Background: Kawasaki disease (KD) is the leading cause of acquired cardiac disease in children, in developed countries. Objectives: To identify predictive factors for resistance to intravenous immunoglobulin (IVIG), calculate the effectiveness of Japanese predictive models and characterize cardiac complications. Methods: Retrospective analysis of KD cases admitted in a Portuguese paediatric hospital between january 2006 and july 2018. ROC curves were used to determine predictive factors for resistance and the multivariate logistic regression analysis was used to develop the predictive model. A significance level of 5% was used. Results: 48 patients with a median age of 36 months were included. The IVIG resistance was 21%. Echocardiographic anomalies were noted in 46%, with coronary involvement in 25% of the sample population. As predictive variable of resistance, the C-reactive protein (CRP) presented an AUC ROC = 0.789, optimal cut-off value 15.1 mg/dL, sensitivity (Sn) 77.8% and specificity (Sp) 78.9%. The erythrocyte sedimentation rate (ESR) presented an AUC ROC = 0.781, optimal cut-off value 90.5 mm/h, Sn 66.7% and Sp 85.7%. The model with the two variables showed p = 0.042 and AUC ROC = 0.790. Predictive strength of Japanese models were: Kobayashi (Sn 63.6%, Sp 77.3%), Egami (Sn 66.7%, Sp 73.1%), Sano (Sn 28.6%, Sp 94.1%). Conclusion: CRP and ESR are independent variables that were related to IVIG resistance, with optimal cut-off points of 15.1 mg/dL and 90.5 mm/h, respectively. About half of the patients had some form of cardiac involvement. The Japanese models appeared to be inadequate in our population. (Arq Bras Cardiol. 2021; 116(3):485-491)

DNA Electrochemical Biosensors for In Situ Probing of Pharmaceutical Drug Oxidative DNA Damage.

Deoxyribonucleic acid (DNA) electrochemical biosensors are devices that incorporate immobilized DNA as a molecular recognition element on the electrode surface, and enable probing in situ the oxidative DNA damage. A wide range of DNA electrochemical biosensor analytical and biotechnological applications in pharmacology are foreseen, due to their ability to determine in situ and in real-time the DNA interaction mechanisms with pharmaceutical drugs, as well as with their degradation products, redox reaction products, and metabolites, and due to their capacity to achieve quantitative electroanalytical evaluation of the drugs, with high sensitivity, short time of analysis, and low cost. This review presents the design and applications of label-free DNA electrochemical biosensors that use DNA direct electrochemical oxidation to detect oxidative DNA damage. The DNA electrochemical biosensor development, from the viewpoint of electrochemical and atomic force microscopy (AFM) characterization, and the bottom-up immobilization of DNA nanostructures at the electrode surface, are described. Applications of DNA electrochemical biosensors that enable the label-free detection of DNA interactions with pharmaceutical compounds, such as acridine derivatives, alkaloids, alkylating agents, alkylphosphocholines, antibiotics, antimetabolites, kinase inhibitors, immunomodulatory agents, metal complexes, nucleoside analogs, and phenolic compounds, which can be used in drug analysis and drug discovery, and may lead to future screening systems, are reviewed.

Nanostructured material-based electrochemical sensing of oxidative DNA damage biomarkers 8-oxoguanine and 8-oxodeoxyguanosine: a comprehensive review.

Oxidative DNA damage plays an important role in the pathogenesis of various diseases. Among oxidative DNA lesions, 8-oxoguanine (8-oxoG) and its corresponding nucleotide 8-oxo-2'-deoxyguanosine (8-oxodG), the guanine and deoxyguanosine oxidation products, have gained much attention, being considered biomarkers for oxidative DNA damage. Both 8-oxoG and 8-oxodG are used to predict overall body oxidative stress levels, to estimate the risk, to detect, and to make prognosis related to treatment of cancer, degenerative, and other age-related diseases. The need for rapid, easy, and low-cost detection and quantification of 8-oxoG and 8-oxodG biomarkers of oxidative DNA damage in complex samples, urine, blood, and tissue, caused an increasing interest on electrochemical sensors based on modified electrodes, due to their high sensitivity and selectivity, low-cost, and easy miniaturization and automation. This review aims to provide a comprehensive and exhaustive overview of the fundamental principles concerning the electrochemical determination of the biomarkers 8-oxoG and 8-oxodG using nanostructured materials (NsM), such as carbon nanotubes, carbon nanofibers, graphene-related materials, gold nanomaterials, metal nanoparticles, polymers, nanocomposites, dendrimers, antibodies and aptamers, and modified electrochemical sensors.

Kawasaki Disease: Predictors of Resistance to Intravenous Immunoglobulin and Cardiac Complications. / Doença de Kawasaki: Preditores de Resistência à Imunoglobulina Intravenosa e Complicações Cardíacas.

BACKGROUND: Kawasaki disease (KD) is the leading cause of acquired cardiac disease in children, in developed countries. OBJECTIVES: To identify predictive factors for resistance to intravenous immunoglobulin (IVIG), calculate the effectiveness of Japanese predictive models and characterize cardiac complications. METHODS: Retrospective analysis of KD cases admitted in a Portuguese paediatric hospital between january 2006 and july 2018. ROC curves were used to determine predictive factors for resistance and the multivariate logistic regression analysis was used to develop the predictive model. A significance level of 5% was used. RESULTS: 48 patients with a median age of 36 months were included. The IVIG resistance was 21%. Echocardiographic anomalies were noted in 46%, with coronary involvement in 25% of the sample population. As predictive variable of resistance, the C-reactive protein (CRP) presented an AUC ROC = 0.789, optimal cut-off value 15.1 mg/dL, sensitivity (Sn) 77.8% and specificity (Sp) 78.9%. The erythrocyte sedimentation rate (ESR) presented an AUC ROC = 0.781, optimal cut-off value 90.5 mm/h, Sn 66.7% and Sp 85.7%. The model with the two variables showed p = 0.042 and AUC ROC = 0.790. Predictive strength of Japanese models were: Kobayashi (Sn 63.6%, Sp 77.3%), Egami (Sn 66.7%, Sp 73.1%), Sano (Sn 28.6%, Sp 94.1%). CONCLUSION: CRP and ESR are independent variables that were related to IVIG resistance, with optimal cut-off points of 15.1 mg/dL and 90.5 mm/h, respectively. About half of the patients had some form of cardiac involvement. The Japanese models appeared to be inadequate in our population. (Arq Bras Cardiol. 2021; 116(3):485-491).

FUNDAMENTO: A doença de Kawasaki (DK) é a principal causa de cardiopatia adquirida em idade pediátrica nos países desenvolvidos. OBJETIVOS: Identificar fatores preditores de resistência à imunoglobulina intravenosa (IGIV), calcular a eficácia dos modelos preditores japoneses e caracterizar as complicações cardíacas. MÉTODOS: Análise retrospectiva dos casos de DK entre janeiro de 2006 e julho de 2018 em um hospital pediátrico português. Foram construídas curvas ROC para encontrar fatores preditores de resistência e utilizada regressão logística multivariada para elaborar o modelo preditor. O nível de significância utilizado foi de 5%. RESULTADOS: Foram incluídos 48 pacientes com mediana de idade de 36 meses. Verificou-se resistência à IGIV em 21%. Ocorreram alterações ecocardiográficas em 46%, com envolvimento coronário em 25%. Como variáveis preditoras de resistência, a proteína C-reativa (PC-R) apresentou uma AUC ROC = 0,789, ponto de corte = 15,1 mg/dL, sensibilidade (S) = 77,8% e especificidade (E) = 78,9%. A velocidade de sedimentação (VS) apresentou uma AUC ROC = 0,781, ponto de corte = 90,5 mm/h, S = 66,7% e E = 85,7%. O modelo com as duas variáveis apresentou valor p = 0,042 e AUC ROC = 0,790. O modelo Kobayashi apresentou S = 63,6% e E = 77,3%; Egami, S = 66,7% e E = 73,1%; e Sano, S = 28,6% e E = 94,1%. CONCLUSÃO: A PC-R e a VS são variáveis independentes que mostraram tendência preditora de resistência à IGIV com pontos de corte ótimos de 15,1 mg/dL e 90,5 mm/h, respectivamente. Cerca de metade dos pacientes teve algum tipo de envolvimento cardíaco. Os modelos japoneses não têm utilidade nessa população. (Arq Bras Cardiol. 2021; 116(3):485-491).

Natural phenolic antioxidants electrochemistry: Towards a new food science methodology.

Natural phenolic compounds are abundant in the vegetable kingdom, occurring mainly as secondary metabolites in a wide variety of chemical structures. Around 10,000 different plant phenolic derivatives have been isolated and identified. This review provides an exhaustive overview concerning the electron transfer reactions in natural polyphenols, from the point of view of their in vitro antioxidant and/or pro-oxidant mode of action, as well as their identification in highly complex matrixes, for example, fruits, vegetables, wine, food supplements, relevant for food quality control, nutrition, and health research. The accurate assessment of polyphenols' redox behavior is essential, and the application of the electrochemical methods in routine quality control of natural products and foods, where the polyphenols antioxidant activity needs to be quantified in vitro, is of the utmost importance. The phenol moiety oxidation pathways and the effect of substituents and experimental conditions on their electrochemical behavior will be reviewed. The fundamental principles concerning the redox behavior of natural polyphenols, specifically flavonoids and other benzopyran derivatives, phenolic acids and ester derivatives, quinones, lignins, tannins, lignans, essential oils, stilbenes, curcuminoids, and chalcones, will be described. The final sections will focus on the electroanalysis of phenolic antioxidants in natural products and the electroanalytical evaluation of in vitro total antioxidant capacity.

Treatment and Outcomes of Children With Febrile Urinary Tract Infection Due to Extended Spectrum Beta-lactamase-producing Bacteria in Europe: TOO CUTE Study.

BACKGROUND: The prevalence of extended-spectrum beta-lactamase producing Εnterobacteriaceae (ESBL-PE) is increasing globally. ESBL-PE are an important cause of urinary tract infections (UTIs) in children. We aimed to characterize the clinical presentation, treatment and outcomes of childhood UTI caused by ESBL-PE in Europe. METHODS: Multicenter retrospective cohort study. Children 0 to 18 years of age with fever, positive urinalysis and positive urine culture for an ESBL-PE uropathogen, seen in a participating hospital from January 2016 to July 2017, were included. MAIN OUTCOME MEASURES: Primary outcome measure: day of defervescence was compared between (1) initial microbiologically effective treatment (IET) versus initial microbiologically ineffective treatment (IIT) and (2) single initial antibiotic treatment versus combined initial antibiotic treatment. SECONDARY OUTCOME MEASURES: Clinical and microbiologic failure of initial treatment. RESULTS: We included 142 children from 14 hospitals in 8 countries. Sixty-one children had IET and 77 IIT. There was no statistical difference in time to defervescence for effective/ineffective groups (P = 0.722) and single/combination therapy groups (P = 0.574). Two of 59 (3.4%) and 4/66 (6.1%) patients exhibited clinical failure during treatment (P = 0.683) when receiving IET or IIT, respectively. Eight of 51 (15.7%) receiving IET and 6/58 (10.3%) receiving IIT patients (P = 0.568) had recurring symptoms/signs suggestive of a UTI. Recurrence of a UTI occurred 15.5 days (interquartile range, 9.0-19.0) after the end of treatment. CONCLUSIONS: Time to defervescence and clinical failure did not differ between IET/IIT groups. Non-carbapenem beta-lactam antibiotics may be used for the empiric treatment of ESBL febrile UTIs, until susceptibility testing results become available.

Calcium channel blocker lercanidipine electrochemistry using a carbon black-modified glassy carbon electrode.

Lercanidipine, a third-generation dihydropyridine calcium L-type channel blocker, redox behavior at different carbon electrode materials, in a wide pH range, using cyclic, square-wave, and differential pulse voltammetry, was studied. A comparison was made between unmodified glassy carbon electrode (GCE) and boron-doped diamond electrode (BDDE), and GCE and BDDE modified with a carbon black (CB) nanoparticle embedded within a dihexadecylphosphate (DHP) nanostructured film (CB-DHP/GCE and CB-DHP/BDDE). Lercanidipine oxidation, for 3.4 < pH < 9.5, is an irreversible, diffusion-controlled, pH-dependent process that occurs in two consecutive steps, with the transfer of one electron and one proton, at the N1 and C4 positions in the 1,4-dihydropyridine ring. For pH > 9.5, both oxidation processes are pH-independent and a pKa = 9.40 was determined. Lercanidipine reduction at pH = 7.0 is an irreversible process, and the lercanidipine reduction products are electroactive and follow a reversible electron transfer reaction. Lercanidipine electroanalytical determination, at a nanostructured GCE modified with a CB-DHP film (CB-DHP/GCE), with no need for N2 purging, with a detection limit of 0.058 µM (3.58 × 10-5 g L-1) and a quantification limit of 0.176 µM (1.08 × 10-4 g L-1), was achieved. Graphical abstract.

Caveolin proteins electrochemical oxidation and interaction with cholesterol.

Caveolae consist in lipid raft domains composed of caveolin proteins, cholesterol, glycosphingolipids, and GPI-anchored proteins. Caveolin proteins present three different types, caveolin 1 (CAV-1), caveolin 2 (CAV-2) and caveolin 3 (CAV-3), with a very similar structure and amino acid composition. The native caveolin proteins oxidation mechanism was investigated for the first time, at a glassy carbon electrode, using cyclic, square wave and differential pulse voltammetry. The three native caveolin proteins oxidation mechanism presented only one tyrosine and tryptophan amino acid residues oxidation peak. Denatured caveolin proteins presented also the tyrosine, tryptophan and cysteine amino acid residues oxidation peaks. The reverse cholesterol transport is related to caveolae and caveolin proteins, and CAV-1 is directly connected to cholesterol transport. The influence of cholesterol on the three caveolin proteins electrochemical behaviour was evaluated. In the absence and in the presence of cholesterol, significant differences in the CAV-1 oxidation peak current were observed.

[Urinary Tract Infections Caused by Community-Acquired Extended-Spectrum ß-Lactamase-Producing Enterobacteriaceae in a Level III Hospital - A Retrospective Study]. / Infeções Urinárias Causadas por Enterobacteriaceae Produtoras de ß-Lactamases de Espetro Expandido Adquiridas na Comunidade num Hospital de Nível III - Um Estudo Retrospetivo.

INTRODUCTION: The emergence of ß-lactamases producing bacteria is a problem worldwide, with increasing importance in communityacquired infections, especially in urinary tract infections. Data regarding the use of non-carbapenem antimicrobials in these infections are scarce. The aim of this study was to analyse the treatment and outcome of urinary tract infections caused by community-acquired ß-lactamase-producing bacteria in children. MATERIAL AND METHODS: Retrospective study performed in a level III paediatric hospital, between June 2007 and December 2017. All children with ß-lactamase-producing Enterobacteriaceae identified in aseptically collected urine culture were included. RESULTS: A total of 175 urinary infections caused by ß-lactamases producing bacteria were diagnosed, 34 (19%) were community-acquired: 25 Escherichia coli (74%), 4 Klebsiella pneumoniae (12%), 4 Proteus mirabilis (12%) and 1 Proteus vulgaris (3%). In 30 (88%) cases, it was the first urinary infection. After identification of the microorganism and antimicrobial susceptibility, 33 (97%) children were re-evaluated and 24 (71%) had a repeat urine culture, which was positive in three (13%). In six (18%) cases, antibiotic treatment was modified. Four (12%) children had another UTI in the following month. In 30 (88%) children, imaging was carried out, with no nephrourological malformations detected. DISCUSSION: In the last decade, about 20% of urinary infections caused by ß-lactamase-producing Enterobacteriaceae were community-acquired with a relatively stable number of cases over the years. No nephro-urological malformations were identified in these children. CONCLUSION: Although the number of cases is small, the clinical and microbiological outcomes showed that most were successfully treated with non-carbapenem antibiotics, with low recurrence of new episodes of urinary tract infections.

Introdução: A emergência de bactérias produtoras de ß-lactamases de espetro expandido é um problema mundial, com importância crescente nas infeções adquiridas na comunidade, nomeadamente nas infeções urinárias. Os dados pediátricos de utilização de antimicrobianos não carbapenemos nestas infeções são escassos. O objetivo do estudo foi analisar a terapêutica antibiótica instituída nas infeções urinárias causadas por estes agentes, assim como a evolução clínica e laboratorial.Material e Métodos: Estudo retrospetivo efetuado num hospital pediátrico entre junho de 2007 e dezembro de 2017. Foram incluídas todas as crianças com urocultura positiva para Enterobacteriaceae produtoras de ß-lactamases.Resultados: Foram diagnosticadas 175 infeções urinárias causadas por Enterobacteriaceae produtoras de ß-lactamases, das quais 34 (19%) foram adquiridas na comunidade: 25 Escherichia coli (74%), 4 Klebsiella pneumoniae (12%), 4 Proteus mirabilis (12%) e 1 Proteus vulgaris (3%). Em 30 (88%) episódios tratou-se da primeira infeção urinária. Após conhecimento do microrganismo e suas suscetibilidades, 33 (97%) crianças foram reavaliadas e 24 (71%) repetiram urocultura, que foi positiva em três (13%). Em seis (18%) casos foi alterado o antimicrobiano. No mês subsequente, quatro (12%) crianças tiveram nova infeção urinária e 30 (88%) crianças realizaram investigação imagiológica, sem deteção de malformações nefro-urológicas.Discussão: Na última década, cerca de 20% das infeções urinárias causadas por Enterobacteriaceae produtoras de ß-lactamases foram adquiridas na comunidade, com um número relativamente estável ao longo dos anos. Estas crianças não apresentavam malformações nefro-urológicas.Conclusão: Embora o número de casos seja pequeno, a evolução clínica e microbiológica mostrou que a maioria foi tratada com sucesso com antimicrobianos não carbapenemos, com baixa ocorrência de novos episódios.

Electrochemical and AFM Characterization of G-Quadruplex Electrochemical Biosensors and Applications.

Guanine-rich DNA sequences are able to form G-quadruplexes, being involved in important biological processes and representing smart self-assembling nanomaterials that are increasingly used in DNA nanotechnology and biosensor technology. G-quadruplex electrochemical biosensors have received particular attention, since the electrochemical response is particularly sensitive to the DNA structural changes from single-stranded, double-stranded, or hairpin into a G-quadruplex configuration. Furthermore, the development of an increased number of G-quadruplex aptamers that combine the G-quadruplex stiffness and self-assembling versatility with the aptamer high specificity of binding to a variety of molecular targets allowed the construction of biosensors with increased selectivity and sensitivity. This review discusses the recent advances on the electrochemical characterization, design, and applications of G-quadruplex electrochemical biosensors in the evaluation of metal ions, G-quadruplex ligands, and other small organic molecules, proteins, and cells. The electrochemical and atomic force microscopy characterization of G-quadruplexes is presented. The incubation time and cations concentration dependence in controlling the G-quadruplex folding, stability, and nanostructures formation at carbon electrodes are discussed. Different G-quadruplex electrochemical biosensors design strategies, based on the DNA folding into a G-quadruplex, the use of G-quadruplex aptamers, or the use of hemin/G-quadruplex DNAzymes, are revisited.

Electrochemistry of Alzheimer Disease Amyloid Beta Peptides.

Alzheimer's disease (AD) is a widespread form of dementia that is estimated to affect 44.4 million people worldwide. AD pathology is closely related to the accumulation of amyloid beta (Aß) peptides in fibrils and plagues, the small oligomeric intermediate species formed during the Aß peptides aggregation presenting the highest neurotoxicity. This review discusses the recent advances on the Aß peptides electrochemical characterization. The Aß peptides oxidation at a glassy carbon electrode occurs in one or two steps, depending on the amino acid sequence, length and content. The first electron transfer reaction corresponds to the tyrosine Tyr10 amino acid residue oxidation, and the second to all three histidine (His6, His13 and His14) and one methionine (Met35) amino acid residues. The Aß peptides aggregation and amyloid fibril formation are electrochemically detected via the electroactive amino acids oxidation peak currents decrease that occurs in a time dependent manner. The Aß peptides redox behaviour is correlated with changes in the adsorption morphology from initially random coiled structures, corresponding to the Aß peptide monomers in random coil or in α-helix conformations, to aggregates, protofibrils and two types of fibrils, corresponding to the Aß peptides in a ß-sheet configuration, observed by atomic force microscopy. Electrochemical studies of Aß peptides aggregation, mediated by the interaction with metal ions, particularly zinc, copper and iron, and different methodologies concerning the detection of Aß peptide biomarkers of AD in biological fluids, using electrochemical biosensors, are also discussed.

Amyloid Beta Peptide VHHQ, KLVFF, and IIGLMVGGVV Domains Involved in Fibrilization: AFM and Electrochemical Characterization.

The time-dependent structural modifications and oxidation behavior of specifically chosen five short amyloid beta (Aß) peptides, Aß1-16, Aß1-28, Aß10-20, Aß12-28, and Aß17-42, fragments of the complete human Aß1-40 peptide, were investigated by atomic force microscopy (AFM) and voltammetry. The objective was to determine the influence of different Aß domains (VHHQ that contains electroactive histidine H residues, KLVFF that is the peptide hydrophobic aggregation core, and IIGLMVGGVV that is the C-terminus hydrophobic region), and of Aß peptide hydrophobicity, in the fibrilization mechanism. The short Aß peptides absence of aggregation or the time-dependent aggregation mechanisms, at room temperature, in free chloride media, within the time window from 0 to 48 h, were established by AFM via changes in their adsorption morphology, and by differential pulse voltammetry, via modifications of the amino acid residues oxidation peak currents. The first oxidation peak was of tyrosine Y residue and the second peak was of histidine H and methionine M residues oxidation. A correlation between the presence of an intact highly hydrophobic KLVFF aggregation core and the time-dependent changes on the Aß peptides aggregation was found. The hydrophobic C-terminal domain IIGLMVGGVV, present in the Aß1-40 peptide, also contributed to accelerate the formation of Aß1-40 peptide aggregates and fibrils.

Pharmaceuticals released from senior residences: occurrence and risk evaluation.

One of the main pursuits, yet most difficult, in monitoring studies is to identify the sources of environmental pollution. In this study, we have identified health-care facilities from south European countries as an important source of pharmaceuticals in the environment. We have estimated that compounds consumed in by the elderly and released from effluents of senior residences can reach river waters at a concentration higher than 0.01 µg/L, which is the European Medicines Agency (EMA) threshold for risk evaluation of pharmaceuticals in surface waters. This study has been based on five health institutions in Portugal, Spain, and France, with 52 to 130 beds. We have compiled the pharmaceuticals dispensed on a daily base and calculated the consumption rates. From 54.9 to 1801 g of pharmaceuticals are consumed daily, with laxatives, analgesics, antiepileptics, antibiotics, and antidiabetic agents being the main drug families administered. According to excretion rates, dilution in the sewerage system, and elimination in wastewater treatment plants, macrogol, metformin, paracetamol, acetylcysteine, amoxicillin, and gabapentin, among others, are expected to reach river waters. Finally, we discuss the risk management actions related to the discharge of pharmaceuticals from senior residences to surface waters.

Alzheimer's disease amyloid beta peptides in vitro electrochemical oxidation.

The oxidative behaviour of the human amyloid beta (Aß1-40 and Aß1-42) peptides and a group of similar peptides: control inverse (Aß40-1 and Aß42-1), mutants (Aß1-40Phe10 and Aß1-40Nle35), rat Aß1-40Rat, and fragments (Aß1-28, Aß1-16, Aß10-20, Aß12-28, and Aß17-42), in solution or adsorbed, at a glassy carbon electrode, by cyclic and differential pulse voltammetry, were investigated and compared. Structurally the Aß1-40 and Aß1-42 sequences contain five electroactive amino acid residues, one tyrosine (Tyr10), three histidines (His6, His13 and His14) and one methionine (Met35). The Aß peptide 3D structure influenced the exposure of the redox residues to the electrode surface and their oxidation peak currents. Depending on the amino acid sequence length and content, the Aß peptides gave one or two oxidation peaks. The first electron transfer reaction corresponded to the tyrosine amino acid residue oxidation, and the second to both histidines and methionine amino acid residues. The highest contribution to the second oxidation peak current was from His13, followed by His14 and His6 residues, and Met35 residue had the lowest contribution. The Aß peptides electron transfer depended on peptide hydrophobicity and 3D structure, the redox residues position in the sequence, the redox residues close to N-termini giving the highest oxidation peak currents.

Calcium-induced calmodulin conformational change. Electrochemical evaluation.

Calmodulin (CaM) is an essential protein present in all eukaryote cells, ranging from vertebrates to unicellular organisms. CaM is the most important Ca2+ signalling protein, composed of two domains, N- and C-terminal domains, linked by a flexible central α-helix, and is responsible for the regulation of numerous calcium-mediated signalling pathways. Four calcium ions bind to CaM, changing its conformation and determining how it recognizes and regulates its cellular targets. The oxidation mechanism of native and denatured CaM, at a glassy carbon electrode, was investigated using differential pulse voltammetry and electrochemical impedance spectroscopy. Native and denatured CaM presented only one oxidation peak, related to the tyrosine amino acid residue oxidation. Calcium-induced calmodulin conformational change and the influence of Ca2+ concentration on the electrochemical behaviour of CaM were evaluated, and significant differences, in the tyrosine amino acid residue peak potential and current, in the absence and in the presence of calcium ions, were observed. Gravimetric measurements were performed with a graphite coated piezoelectric quartz crystal with adsorbed CaM, and calcium aggregation by CaM was demonstrated.