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Juan S Izquierdo-Condoy,1 Patricio Naranjo-Lara,1 Fabián D Arias Rodríguez,2 Alexander Gilberto Puglla-Mendoza,1 Jackson Jima-Sanmartín,1 Dayana Andrade Casanova,1 Erick Patricio Duque-Sánchez,1 Nicolás Alegría N,1 Marlon Guillermo Rojas Cadena,1 Esteban Ortiz-Prado1 1One Health Research Group, Faculty of Medicine, Universidad de las Américas, Quito, Ecuador; 2Área de Gestión de Docencia e Investigación, Hospital Pediátrico Baca Ortiz, Quito, EcuadorCorrespondence: Esteban Ortiz-Prado, One Health Research Group, Universidad de las Américas, Ecuador Calle de los Colimes y Avenida De los Granados, Quito, 170137, Ecuador, Tel +593995760693, Email e.ortizprado@gmail.comPurpose: Cardiorespiratory arrest’s unpredictability poses a global health challenge, with gaps in physicians’ life support knowledge potentially leading to poor patient outcomes, a factor yet unstudied among Ecuadorian physicians. This study aims to elucidate the state of physicians’ theoretical knowledge in Ecuador based on Basic Life Support (BLS) and Advanced Life Support (ALS) guidelines.Patients and methods: A national cross-sectional online 35-questions survey was conducted between February and March 2023 using a self-administered, expert-validated questionnaire. Participants’ responses were obtained through official social media groups (WhatsApp and Facebook). The survey evaluated the theoretical knowledge of BLS and ALS, with scores based on the number of correct answers out of a maximum of 10.0 points. For descriptive analysis, frequencies, percentages, means, and standard deviations (SD) were used. The T-test and one-way ANOVA were utilized to analyze the associations between knowledge levels and demographic and academic training variables of Ecuadorian doctors. Values of p < 0.05 were considered statistically significant for all analyses.Results: The survey garnered responses from 385 physicians, with a majority being female (56.6%) and possessing less than 3 years of work experience (75.1%). Of these, 71.7% and 51.9% held BLS and ALS certifications, respectively. Knowledge scores for BLS (5.8/10 ± 1.6) surpassed those for ALS (4.7/10 ± 1.8) (p < 0.001). Physicians with less than 3 years of work experience exhibited higher knowledge scores in both BLS and ALS tests (p < 0.05).Conclusion: This study revealed a notable deficiency in the theoretical knowledge of BLS and ALS among surveyed Ecuadorian physicians. Factors such as prior certification and years of work experience appeared to influence knowledge levels. Continual training and updates in life support protocols at universities and healthcare institutions are key to enhancing physicians’ skills and patient outcomes.Keywords: cardiopulmonary resuscitation, knowledge, education, medical, physicians

En Esparza (Costa Rica) se evaluó la viabilidad de invertir en bancos forrajeros (BF) como alternativa de suplementación para vacas en sistema doble propósito durante la época seca (125 días). Se usaron como indicadores de rentabilidad el Valor Presente Neto (VPN) y la Tasa Interna de Retorno (TIR). Se realizó un análisis de sensibilidad para el incremento del precio de la leche, los concentrados, la gallinaza y la mano de obra. Los modelos se elaboraron comparando los BF de plantas leñosas perennes de corte y acarreo de Cratylia argentea + caña de azúcar (Saccharum officinarum) (BFC) y de ramoneo Leucaena leucocephala (BFL) vs. suplementos comerciales tipos concentrado y gallinaza. En los BFC se requirieron 71.1 jornales/año y el análisis financiero indicó que son rentables al compararlos con la gallinaza (VPN = US$362.2, TIR = 17%) y concentrados (VPN = US$1953.9; TIR=39%). En BFL se requirieron 13 jornales/año y fueron igualmente rentables en comparación con gallinaza (VPN = US$1594.7; TIR = 21%) y con concentrados (VPN = US$3619.6; TIR=35%). Los modelos fueron sensibles a la producción y cambios de precios en la leche, gallinaza, concentrados y el valor del jornal. Los BF son una buena alternativa para la suplementación de ganado en la época seca y una importante fuente de empleo en la región; sin embargo, los altos costos de la mano de obra contratada pueden limitar la adopción.

Healthcare-associated infections (HAIs) pose significant challenges to global health due to pathogen complexity and antimicrobial resistance. Biosensors utilizing antimicrobial peptides offer innovative solutions. Hylarana picturata Multiple Active Peptide 1 (Hp-MAP1), derived from Temporin-PTA, exhibits antibacterial properties sourced from the skin secretions of the Malaysian fire-bellied frog. An innovative sensing layer was developed for the electrochemical biorecognition of diverse pathogens: Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus. Electrochemical impedance spectroscopy differentiated microorganisms based on distinct electrochemical responses. The sensor layer, composed of functionalized multi-walled carbon nanotubes (MWCNTs) associated with Hp-MAP1, exhibited varying levels of charge transfer resistance (R CT ) for different microorganisms. Gram-negative species, especially P. aeruginosa, displayed higher R CT values, indicating better impedimetric responses. Excellent LODs were observed for P. aeruginosa (0.60), K. pneumoniae (0.42), E. coli (0.67), and S. aureus (0.59), highlighting the efficacy of the MWCNTs/Hp-MAP1 biosensor in microbial identification. The MWCNTs/Hp-MAP1 biosensor platform presents a promising and effective microbial identification strategy with potential healthcare applications to mitigate HAIs and enhance patient care., (© 2024 American Institute of Chemical Engineers.)

Infections caused by microorganisms are a public health problem worldwide. New biodetection systems are essential to diagnose with accuracy resulting in more effective treatment. In this work, we propose a ConA-conjugated graphene quantum dots and polypyrrole film-based biosensor for label-free detection of Candida albicans, Candida glabrata, Candida tropicalis, E. coli, B. subitilis, and S. aureus. We modified polypyrrole and graphene quantum dots (PPY-QDGs) with Concanavalin A (Con A) lectin. ConA is a glucose/mannose-specific lectin. The results showed that ConA lectin has the highest binding affinity for C. tropicalis and S. subtilis. PPY-GQDs-ConA binding profile revealed differential response for Candida spp (C. tropicalis > C. albicans > C. glabrata) and bacterial (B. subtilis > S. aureus > E. coli). The limits of detection (LOD) obtained were 1.42 CFU/mL for C. albicans, and 3.72 CFU/mL for C. glabrata. C. tropicalis yielded a LOD of 0.18 CFU/mL. The respective LODs for the evaluated bacteria were 0.39 CFU/mL for S. aureus, 0.72 CFU/mL for S. subtilis, and 2.63 CFU/mL for E. coli. The differential response obtained for the sensor can be attributed to the heterogeneous distribution of carbohydrates on the microorganism's surfaces. The proposed system based on a flexible substrate is effective for microbiological diagnosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

E6 and E7 oncogenes are pivotal in the carcinogenic transformation in HPV infections and efficient diagnostic methods can ensure the detection and differentiation of HPV genotype. This study describes the development and validation of an electrochemical, label-free genosensor coupled with a microfluidic system for detecting the E6 and E7 oncogenes in cervical scraping samples. The nanostructuring employed was based on a cysteine and graphene quantum dots layer that provides functional groups, surface area, and interesting electrochemical properties. Biorecognition tests with cervical scraping samples showed differentiation in the voltammetric response. Low-risk HPV exhibited a lower biorecognition response, reflected in ΔI% values of 82.33 % ± 0.29 for HPV06 and 80.65 % ± 0.68 for HPV11 at a dilution of 1:100. Meanwhile, high-risk, HPV16 and HPV18, demonstrated ΔI% values of 96.65 % ± 1.27 and 93 % ± 0.026, respectively, at the same dilution. Therefore, the biorecognition intensity followed the order: HPV16 >HPV18 >HPV06 >HPV11. The limit of detection and the limit of quantification of E6E7 microfluidic LOC-Genosensor was 26 fM, and 79.6 fM. Consequently, the E6E7 biosensor is a valuable alternative for clinical HPV diagnosis, capable of detecting the potential for oncogenic progression even in the early stages of infection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The objective of this systematic review is to analyze the diagnostic accuracy of rapid dengue diagnostic tests. The search was conducted in the following databases: LILACS, Medline (Pubmed), CRD, The Cochrane Library, Trip Medical Database and Google Scholar. ELISA and PCR assays were adopted as reference methods. Thirty-four articles were included in this systematic review. Receiver operating characteristic (ROC) and Forest Plot were performed to evaluate sensitivity and specificity for each parameter analyzed (NS1, IgM and IgG). The results revealed that the combined analysis of the IgM antibody with the NS1 antigen resulted in greater sensitivity than the isolated analysis of IgM. The three analytes together showed the best performance, with a combined sensitivity of 90 % (95 % CI: 89-92 %) using ELISA as a comparator. Thus, the present review provides relevant knowledge for decision-making between the available rapid diagnostic tests., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Population shift towards healthier lifestyles can help reduce the burden of type 2 diabetes mellitus (DM), therefore understanding and monitoring the lifestyle-related risk factors are crucial for setting up effective preventive strategies and disease management. The present study aimed to explore the changes in prevalence of DM and major risk factors including smoking, physical activity, fruit and vegetable consumption, as well as body mass index (BMI) over three waves of European Health Interview Survey, and to investigate the association between risk factors and presence of DM across 11 European Union member states. Poisson regression models were used to evaluate the association between risk factors and DM, adjusted for demographic and socioeconomic variables. The estimated age-standardized prevalence of DM increased from 7.01% in 2009 to 7.96% in 2019, with substantial increase in subgroups with higher BMI and unhealthy lifestyle including physically inactive people, or current smokers. Obesity and overweight and physical inactivity were significantly associated with DM in all survey waves. Our findings underline that obesity prevention and weight loss promotion along with physical activity promotion are the subject of lifestyle interventions to reduce the burden of DM in EU member states., (© 2024. The Author(s).)

Objectives: To evaluate the stability of periodontal tissues 3 (T 3 ), 6 (T 6 ), and 12 (T 12 ) months after esthetic crown lengthening (ACL) and the possible correlations between changes in those structures., Materials and Methods: Twenty individuals were evaluated through clinical assessment, photography, and tomography. Measurements included gingival margin (GM), clinical crown length (CCL), interdental papilla height (PH) and width (PW), gingival thickness (GT), bone thickness (BT), probing depth (PD), distance between alveolar crest and GM, distance between alveolar crest and cementoenamel junction. Nonparametric and correlation statistics were performed (p < 0.05)., Results: CCL at T 0 was 7.42 ± 0.70 mm and increased to 9.48 ± 0.49 mm immediately after ACL, but it decreased to 8.93 ± 0.65 mm at T 12 . PD decreased 0.60 mm from T 0 to T 6 , and it increased 0.39 mm from T 6 to T 12 . BT decreased 0.20 mm, while GT increased 0.29 mm from T 0 to T 12 . Both PW and PH showed enlargement in T 12 . A positive moderate correlation was found between CCL/T 0 and CCL/T 12 , GT/T 0 and AC-GM/T 12 , BT/T 0 and GT/T 12 . A few negative moderate correlations were PD/T 0 and CCL/T 12 , PD/T 0 and PH/T 0 , PD/T 0 and BT/T 12 ., Conclusions: ACL procedure was effective. Although some rebound occurred, that was not clinically important. PD tended to reestablish its original length, partially due to a migration of GM during the healing period. Besides, a thickening of supracrestal soft tissues was observed., Clinical Relevance: The present study centers on the factors influencing the stability of periodontal tissues after esthetic crown lengthening, underscoring the procedure's influence on esthetics and biology and the need for careful treatment planning., (© 2024. The Author(s).)

Acute promyelocytic leukemia (APL) in children is associated with a favorable initial prognosis. However, minimal residual disease (MRD) follow-up remains poorly defined, and relapse cases are concerning due to their recurrent nature. Thus, we report two electrochemical flexible genosensors based on polypyrrole (PPy) and graphene quantum dots (GQDs) for label-free PML-RARα oncogene detection. Atomic force microscopy (AFM), scanning electron microscope (SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) were used to characterize the technological biosensor development. M7 and APLB oligonucleotide sequences were used as bioreceptors to detect oncogenic segments on chromosomes 15 and 17, respectively. AFM characterization revealed heterogeneous topographical surfaces with maximum height peaks for sensor layers when tested with positive patient samples. APLB/Genosensor exhibited a percentage change in anode peak current (ΔI) of 423 %. M7/Genosensor exhibited a ΔI of 61.44 % for more concentrated cDNA samples. The described behavior is associated with the biospecific recognition of the proposed biosensors. Limits of detection (LOD) of 0.214 pM and 0.677 pM were obtained for APLB/Genosensor and M7/Genosensor, respectively. The limits of quantification (LOQ) of 0.648 pM and 2.05 pM were estimated for APLB/Genosensor and M7/Genosensor, respectively. The genosensors showed reproducibility with a relative standard deviation of 7.12 % for APLB and 1.18 % for M7 and high repeatability (9.89 % for APLB and 1.51 % for M7). In addition, genetic tools could identify the PML-RARα oncogene in purified samples, plasmids, and clinical specimens from pediatric patients diagnosed with APL with high bioanalytical performance. Therefore, biosensors represent a valuable alternative for the clinical diagnosis of APL and monitoring of MRD with an impact on public health., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Although overall health status in the last decades improved, health inequalities due to non-communicable diseases (NCDs) persist between and within European countries. There is a lack of studies giving insights into health inequalities related to NCDs in the European Economic Area (EEA) countries. Therefore, the aim of the present study was to quantify health inequalities in age-standardized disability adjusted life years (DALY) rates for NCDs overall and 12 specific NCDs across 30 EEA countries between 1990 and 2019. Also, this study aimed to determine trends in health inequalities and to identify those NCDs where the inequalities were the highest., Methods: DALY rate ratios were calculated to determine and compare inequalities between the 30 EEA countries, by sex, and across time. Annual rate of change was used to determine the differences in DALY rate between 1990 and 2019 for males and females. The Gini Coefficient (GC) was used to measure the DALY rate inequalities across countries, and the Slope Index of Inequality (SII) to estimate the average absolute difference in DALY rate across countries., Results: Between 1990 and 2019, there was an overall declining trend in DALY rate, with larger declines among females compared to males. Among EEA countries, in 2019 the highest NCD DALY rate for both sexes were observed for Bulgaria. For the whole period, the highest DALY rate ratios were identified for digestive diseases, diabetes and kidney diseases, substance use disorders, cardiovascular diseases (CVD), and chronic respiratory diseases - representing the highest inequality between countries. In 2019, the highest DALY rate ratio was found between Bulgaria and Iceland for males. GC and SII indicated that the highest inequalities were due to CVD for most of the study period - however, overall levels of inequality were low., Conclusions: The inequality in level 1 NCDs DALYs rate is relatively low among all the countries. CVDs, digestive diseases, diabetes and kidney diseases, substance use disorders, and chronic respiratory diseases are the NCDs that exhibit higher levels of inequality across countries in the EEA. This might be mitigated by applying tailored preventive measures and enabling healthcare access., (© 2023. The Author(s).)

Chronic ulcers of the lower limbs are common and recurrent, especially in the elderly population, they are disabling injuries that generate a great socioeconomic burden. This scenario encourages the development of new, low-cost therapeutic alternatives. The present study aims to describe the use of bacterial cellulose in the treatment of lower limb ulcers. This is an integrative literature review, carried out in the PubMed and Science Direct databases by associating the descriptors, with the inclusion criteria being clinical studies in the last 5 years, available in full in English, Portuguese and Spanish. Five clinical trials were analyzed and the main therapeutic effects obtained in the experimental groups that used bacterial cellulose dressings were a reduction in the area of the wounds, one of the studies showed a reduction of 44.18cm2 in the area of the wound, the initial lesions measured on average 89.46cm2 and at the end of the follow-up, they had an average of 45.28cm2, since the reduction in pain and the decrease in the number of exchanges were advantages described in all groups that used the BS. It is concluded that BC dressings are an alternative for the treatment of lower limb ulcers, their use also reduces operational costs related to the treatment of ulcers.

Systemic sclerosis (SSc) is a chronic, autoimmune disease that primarily affects connective tissue. SSc can be classified into limited cutaneous (lSSc) and diffuse cutaneous (dSSc). Oncostatin M receptor (sOSMR) is an important inflammatory biomarker expressed in the serum of patients with autoimmune diseases. A nanoengineered immunosensor surface was developed. The biosensor was composed of a conductive layer of polypyrrole, electrodeposited gold nanoparticles, and sOSMR protein for anti-human OSMR monoclonal antibody biorecognition. The electrochemical response evaluated by cyclic voltammetry and electrochemical impedance spectroscopy indicated the detection of the target analyte present in clinical samples from lSSc and dSSc patients. The voltammetric anodic shift for lSSc specimens was 82.7% ± 0.9-93.6% ± 3.2, and dSSc specimens was 118.7 ± 2.6 to 379.6 ± 2.6, revealing a differential diagnostic character for SSc subtypes. The sensor platform was adapted for identifying sOSMR, using anti-OSMR antibodies as bioreceptors. With a linear response range estimated from 0.005 to 500 pg mL -1 and a limit of detection of 0.42 pg mL -1 , the sensing strategy demonstrated high sensitivity in identifying the human OSMR protein in clinical samples. The proposed biosensor is a promising and innovative tool for SSc-related biomarker research., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

This article developed a novel electrochemical immunosensor for the specific detection of aflatoxin B1 (AFB1). Amino-functionalized iron oxide nanoparticles (Fe 3 O 4 -NH 2 ) were synthesized. Fe 3 O 4 -NH 2 were chemically bound on self-assembly monolayers (SAMs) of mercaptobenzoic acid (MBA). Finally, polyclonal antibodies (pAb) were immobilized on Fe 3 O 4 -NH 2 -MBA. The sensor system was evaluated through atomic force microscopy (AFM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). A reduction in the anodic and cathodic peak currents was observed after the assembly of the sensor platform. The charge transfer resistance (R ct ) was increased due to the electrically insulating bioconjugates. Then, the specific interaction between the sensor platform and AFB1 blocks the electron transfer of the [Fe(CN) 6 ] 3-/4- redox pair. The nanoimmunosensor showed a linear response range estimated from 0.5 to 30 μg/mL with a limit of detection (LOD) of 9.47 μg/mL and a limit of quantification (LOQ) of 28.72 μg/mL for AFB1 identification in a purified sample. In addition, a LOD of 3.79 μg/mL, a LOQ of 11.48 μg/mL, and a regression coefficient of 0.9891 were estimated for biodetection tests on peanut samples. The proposed immunosensor represents a simple alternative, successfully applied in detecting AFB1 in peanuts, and therefore, represents a valuable tool for ensuring food safety., (© 2023 American Institute of Chemical Engineers.)

The present research refers to elaborating a new label-free electrochemical biosensor used to detect the BCR/ABL fusion gene. We used a hybrid nanocomposite composed of chitosan and zinc oxide nanoparticles (Chit-ZnONP) immobilized on a polypyrrole (PPy) film. DNA segments were covalently immobilized, allowing biomolecular recognition. Atomic force microscopy (AFM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) were used to evaluate the assembly stages of the biosensor. The biosensor's analytical performance was investigated using recombinant plasmids containing the target oncogene and clinical samples from patients with chronic myeloid leukemia (CML). A limit of detection (LOD) of 1.34 fM, limit of quantification (LOQ) of 4.08 fM, and sensitivity of 34.03 μA fM -1 cm 2 were calculated for the BCR/ABL fusion oncogene. The sensing system exhibited high specificity, selectivity, and reproducibility with a standard deviation (SD) of 4.21%. Additionally, a linear response range was observed between 138.80 aM to 13.88 pM with a regression coefficient of 0.96. Also, the biosensor shows easy operationalization and fast analytical response, contributing to the early cancer diagnosis. The proposed nanostructured device is an alternative for the genetic identification BCR/ABL fusion gene., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The increasing number of multidrug resistance microorganisms is an alarming threat, and their rapid detection is essential to prevent nosocomial, foodborne, or waterborne infections. Many peptides derived from the venom of wasp Synoeca surinama have antimicrobial activity against Gram-positive and Gram-negative bacteria. Synoeca-MP, an antimicrobial peptide (AMP) from mastoparan family, seems to increase bacterial membrane permeability, promoting cytotoxicity and membrane disruption. Here Synoeca-MP was evaluated as biorecognition element tethered over chitosan-coated magnetic nanoparticles (Fe 3 O 4 -Chit). The transducing layer of the biosensor was developed from the self-assembling of 4-mercaptobenzoic acid (4-MBA) monolayer onto gold substrate. Atomic force microscopy (AFM) analyses confirmed the biointeraction between AMP and different pathogens membranes. The fabrication and performance of the biosensing assembly were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Detection of Enterococcus faecalis (G+), Klebsiella pneumoniae (G-), Pseudomonas aeruginosa (G-), and Candida tropicalis was assessed in a recognition range from 10 1 to 10 5 CFU.mL -1 . An instrumental limit of detection of 10 CFU.mL -1 was obtained for each specimen. However, the device presented a preferential selectivity towards Gram-negative bacteria. The proposed biosensor is a sensitive, fast, and straightforward platform for microbial detection in aqueous samples, envisaged for environmental monitoring applications., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Rapid immunochromatographic tests are frequently used to diagnose dengue due to their easy use, low cost, and fast response. A high level of accuracy is essential for rapid diagnostic tests to support their large-scale use. Thus, this systematic review aims to evaluate the accuracy of rapid dengue diagnostic tests. The investigation was run through the following databases: LILACS, Medline (Pubmed), CRD, The Cochrane Library, Trip Medical Database, and Google Scholar. To solve difficulties, two independent reviewers performed document screening and selection. ELISA assay was adopted as a reference test because of several methodologic advantages. Seventeen articles were included accordingly, reckoning 6837 participating individuals. The receiver operating characteristic (ROC) and Forest Plot were conducted to evaluate the sensitivity and specificity for each analyzed parameter (anti-dengue IgM, IgG, and NS1 antigen). The risk of bias and quality of evidence were assessed as moderate using QUADAS-2 and Grading of Recommendations Assessment, Development, and Evaluation (GRADE), respectively. The sensitivity of IgM concerning the studied tests ranged from 13.8 to 90%, while that of NS1 ranged from 14.7 to 100% (95% CI). The antibodies with NS1 presented increased sensitivity; pooled data show that the association of the three analytes bestows the best result, with a combined sensitivity of 90% (CI 95%: 87-92%) and a pooled specificity of 89% (CI 95%: 87-92%). Thus, the present review provides relevant knowledge for decision-making between available rapid diagnostic tests., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Bacterial and fungal infections are challenging due to their low susceptibility and resistance to antimicrobial drugs. For this reason, antimicrobial peptides (AMP) emerge as excellent alternatives to overcome these problems. At the same time, their active insertion into the cell wall of microorganisms can be availed for biorecognition applications in biosensing platforms. Temporin-PTA (T-PTA) is an AMP found in the skin secretions of the Malaysian fire frog Hylarana picturata, which presents antibacterial activity against MRSA, Escherichia coli, and Bacillus subtilis. In this work, T-PTA was explored as an innovative sensing layer aiming for the electrochemical differentiation of Klebsiella pneumoniae, Acinetobacter baumannii, Bacillus subtilis, Enterococcus faecalis, Candida albicans, and C. tropicalis based on the structural differences of their membranes. The biosensor was analyzed through electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). In this approach, the different structural features of each microorganism resulted in different adherence degrees and, therefore, different electrochemical responses. The transducing layer was fabricated by the self-assembling of a 4-mercaptobenzoic acid (MBA) monolayer and gold-capped magnetic nanoparticles (Fe 3 O 4 @Au) implemented to improve the electrical signal of the biointeraction. We found that each interaction, expressed in variations of electron transfer resistance and anodic peak current, demonstrated a singular response from which the platform can discriminate all different microorganisms. We found expressive sensitivity towards Gram-negative species, especially K. pneumoniae. A detection limit of 10 1 CFU.mL -1 and a linear range of 10 1 to 10 5 CFU.mL -1 were obtained. The T-PTA biosensor platform is a promising and effective tool for microbial identification., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Objectives: To evaluate the survival rate, success rate, and peri-implant biological changes of immediately loaded dental implants (ILs) placed in type 2 diabetic patients (DM2)., Materials and Methods: The present study was registered on PROSPERO and followed the PRISMA checklist. The search was performed by the first reviewer in January 2021. The electronic databases used were MEDLINE via PubMed, Cochrane, BVS, Web of Science, Scopus, LIVIVO, and gray literature. The risk of bias analysis was performed using an instrument from the Joanna Briggs Institute., Results: A total of 3566 titles and abstracts were obtained. The qualitative synthesis included 7 studies, while the quantitative synthesis included 5 studies. The meta-analysis of IL in individuals with DM2 compared to nondiabetic individuals showed no significant difference among the groups regarding the survival rate of dental implants (RR = 1.00, 95% CI 0.96-1.04; p = 0.91; I 2  = 0%), even if the patient had poor glycemic control (RR = 1.08, 95% CI 0.87-1.33; p = 0.48; I 2  = 70%). Meta-analysis of marginal bone loss in IL compared to conventional loading in DM2 patients also showed no significant difference (mean difference =  - 0.08, 95% CI - 0.25-0.08; p = 0.33; I 2  = 83%)., Conclusions: Type 2 diabetes mellitus does not seem to be a risk factor for immediately loaded implants if the glycemic level is controlled, the oral hygiene is satisfactory, and the technical steps are strictly followed. Clinical relevance Rehabilitation in diabetic individuals is more common due to the highest prevalence of edentulism in this population. It is essential to establish appropriate protocols for loading dental implants., (© 2021. The Author(s).)

Zika virus (ZIKV) infection is associated with the Guillain-Barré syndrome, and when non-vector congenital transmission occurs, fetal brain abnormalities are expected. After ZIKV infection, the blood, breast milk, and other body fluids contain low viral loads. Their detection is challenging as it requires the processing of larger input volumes of the clinical samples. Pre-enrichment is a valuable strategy to increase the analyte concentration. Therefore, the authors propose the use of a hierarchal composite polyaniline-(electrospun nanofiber) hydrogel mat (ENM) for the simultaneous enrichment and impedimetric sensing of ZIKV viral particles. The electrospinning conditions of polyvinyl alcohol and alginate, including blend formulation, were optimized through a factorial design. Disintegration and gelatinization were controlled via cross-linking to improve the hydrogel properties. Hierarchization was achieved by in situ chemical deposition of conductive polyaniline. The carboxyl groups of the ENM were used for the covalent immobilization of anti-ZIKV polyclonal antibodies used in the specific recognition of ZIKV within the medium of Vero cell culture. The specific capture and desorption of virions were studied at different pHs. ENMs were characterized by scanning electron microscopy and FTIR. Atomic force microscopy along with UV-vis and electrochemical impedance spectroscopies was used to monitor the antibody immobilization, ZIKV capture, and elution processes. Our results show that 14.2 mg (0.25 cm 3 ) of ENM can capture 38.7 ± 2.5 μg of ZIKV with a desorption rate of 99.97% (38.29 ± 2.7 μg ZIKV), which is reusable for at least three times. Therefore, the capture capacity (micrograms of ZIKV captured per milligram of ENM) of polyaniline-hierarchized mats was 2.72 μg ZIKV/mg. The impedance LOD value was determined to be 2.76 μg of ZIKV particles (approximately 6.6 × 103 PFU/mL). As a result, we present a fast small-scale purification system that can simultaneously monitor ZIKV electrochemically and optically.

The projection of new biosensing technologies for genetic identification of SARS-COV-2 is essential in the face of a pandemic scenario. For this reason, the current research aims to develop a label-free flexible biodevice applicable to COVID-19. A nanostructured platform made of polypyrrole (PPy) and gold nanoparticles (GNP) was designed for interfacing the electrochemical signal in miniaturized electrodes of tin-doped indium oxide (ITO). Oligonucleotide primer was chemically immobilized on the flexible transducers for the biorecognition of the nucleocapsid protein (N) gene. Methodological protocols based on cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and atomic force microscopy (AFM) were used to characterize the nanotechnological apparatus. The biosensor's electrochemical performance was evaluated using the SARS-CoV-2 genome and biological samples of cDNA from patients infected with retrovirus at various disease stages. It is inferred that the analytical tool was able to distinguish the expression of SARS-CoV-2 in patients diagnosed with COVID-19 in the early, intermediate and late stages. The biosensor exhibited high selectivity by not recognizing the biological target in samples from patients not infected with SARS-CoV-2. The proposed sensor obtained a linear response range estimated from 800 to 4000 copies µL -1 with a regression coefficient of 0.99, and a detection limit of 258.01 copies µL -1 . Therefore, the electrochemical biosensor based on flexible electrode technology represents a promising trend for sensitive molecular analysis of etiologic agent with fast and simple operationalization. In addition to early genetic diagnosis, the biomolecular assay may help to monitor the progression of COVID-19 infection in a novel manner., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Biosensors are pre-prepared diagnostic devices composed of at least one biological probe. These devices are envisaged for the practical identification of specific targets of microbiological interest. In recent years, the use of narrow-specific probes such as lectins has been proven to distinguish bacteria and glycoproteins based on their superficial glycomic pattern. For instance, Concanavalin A is a carbohydrate-binding lectin indicated as a narrow-specific biological probe for Gram-negative bacteria. As a drawback, Gram-positive bacteria are frequently overlooked from lectin-based biosensing studies because their identification results in low resolution and overlapped signals. In this work, the authors explore the effect that platform nanostructuration has over the electrochemical response of ConA-based platforms constructed for bacterial detection; one is formed of chitosan-capped magnetic nanoparticles, and another is composed of gold nanoparticle-decorated magnetic nanoparticles. The biosensing platforms were characterized by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) as a function of bacterial concentration. Our results show that probe-target interaction causes variations in the electrical responses of nanostructured transducers. Moreover, the association of gold nanoparticles to magnetic nanoparticles resulted in an electrical enhancement capable of overcoming low resolution and overlapping Gram-positive identification. Both platforms attained a limit of detection of 10 ° CFU mL -1 , which is useful for water analyses and sanitation concerns, where low CFU mL -1 are always expected. Although both platforms were able to detect Gram-negative bacteria, Gram-positives were only correctly differentiated by the gold nanoparticle-decorated magnetic nanoparticles, thus demonstrating the positive influence of hierarchically nanostructured platforms., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

Since healthy eating and physically active lifestyles can reduce diabetes mellitus (DM) risk, these are often addressed by population-based interventions aiming to prevent DM. Our study examined the impact of nutritional and physical activity policies, national diabetes plans and national diabetes registers contribute to lower prevalence of DM in individuals in the member states of the European Union (EU), taking into account the demographic and socioeconomic status as well as lifestyle choices. Datasets on policy actions, plans and registers were retrieved from the World Cancer Research Fund International's NOURISHING and MOVING policy databases and the European Coalition for Diabetes report. Individual-based data on DM, socioeconomic status and healthy behavior indicators were obtained via the European Health Interview Survey, 2014. Our results showed variation in types and numbers of implemented policies within the member states, additionally, the higher number of these actions were not associated with lower DM prevalence. Only weak correlation between the prevalence of DM and preventive policies was found. Thus, undoubtedly policies have an impact on reducing the prevalence of DM, its increasing burden could not be reversed which underlines the need for applying a network of preventive policies.

Diabetes mellitus (DM) is a high-risk non-communicable disease with an emerging burden for the European Union (EU) member states in the past decades. The unfavorable trend of the burden is striking compared to the declining disease burden due to cardiovascular diseases or stagnation of neoplasms. The goal of this study is to describe the temporal changes of diabetes in the adult population of Slovakia through the three European Health Interview Survey (EHIS) waves and to assess the association between DM and socioeconomic and/or lifestyle characteristics. These cross-sectional studies were carried out using microdata derived from Slovakia's EHISs conducted in the years 2009 ( n = 4972), 2014 ( n = 5490), and 2019 ( n = 5527). The DM variable was compared to the independent variables such as sociodemographic and lifestyle characteristics including dietary patterns and physical activity. DM prevalence for the EHIS in 2009, 2014, and 2019 were 6.1%, 8.2%, and 9.8%, respectively. In bivariate analysis, the relationship between DM and age, education level, job status, BMI, walking for at least 10 min, and physical activity was significant in the three EHISs. In 2014 and 2019, there was an inverse association between the risk of DM and walking regularly. There was no association between the frequency of eating fruits or vegetables and DM, with the exception of 2009, where a negative association between eating vegetables one to six times a week and DM was observed. Present health policies and activities in Slovakia were unable to reverse the increasing DM burden, indicating that a more systematic approach is needed. Complex policy strategies and legislative measures must be developed and implemented at both the national and EU levels.

Considering the low sensitivity of cytological exams and high costs of the molecular methods, the development of diagnostic tests for effective diagnosis of HPV infections is a priority. In this work, biosensor composed of polypyrrole (PPy) films and gold nanoparticles (AuNPs) was obtained for specific detection of HPV genotypes. The biosensor was developed by using flexible electrodes based on polyethylene terephthalate (PET) strips coated with indium tin oxide (ITO). Polymeric films and AuNPs were obtained by electrosynthesis. Oligonucleotides sequences modified with functional amino groups were designed to recognize HPV gene families strictly. The modified oligonucleotides were chemically immobilized on the nanostructured platform. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used for the analysis of the electrode modification and monitoring of molecular hybridization. Electrochemical changes were observed after exposure of the biosensors to plasmid samples and cervical specimens. The biosensor based on the BSH16 probe showed a linear concentration range for target HPV16 gene detection of 100 pg μL -1 to 1 fg μL -1 . A limit of detection (LOD) of 0.89 pg μL -1 and limit of quantification (LOQ) of 2.70 pg μL -1 were obtained, with a regression coefficient of 0.98. Screening tests on cervical specimens were performed to evaluate the sensibility and specificity for HPV and its viral family. The expression of a biomarker for tumorigenesis (p53 gene) was also monitored. In this work, a flexible system has been successfully developed for label-free detection of HPV families and p53 gene monitoring with high specificity, selectivity, and sensitivity., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The associations among early childhood caries (ECC), socioeconomic status, and sugar consumption are of the utmost importance, due to their potential policy implications. The purpose of this study was to identify trends in ECC burden in children under 5 years old among European Union (EU) member states over time and to evaluate the relationship with its risk factors. Global Burden of Disease 2019 data were analyzed to estimate the burden of ECC over time, specifically incidence, prevalence, and years lived with disability (YLDs) for children under 5 years old. Four ecological variables with a potential effect on YLDs for ECC were used to investigate the association between 2014 and 2017. The YLDs rate was consistently higher among Eastern EU countries over time. Univariate models showed a positive significant association between at-risk-of-poverty rate and YLDs rate, while GDP per capita and urbanization were inversely associated with YLDs rate. In the multivariate analysis, sugar consumption, GDP per capita and urbanization showed significant association with YLDs rate. After stratification by region, association remained significant only in the Eastern EU countries between GDP, urbanization, and YLDs rate, while sugar consumption and at-risk-of-poverty rate had no significant impact on YLDs rates. This study found increasing ECC burden in the EU. The complexity of the problem indicates the need for innovative and personalized policy approaches to tackle the disease.

Fungi stand out as primary pathogens present in healthcare-acquired infections, presenting an increased number of cases even using appropriate antifungal therapy. Candida spp. is a predominant microorganism among several fungal pathogens present in the healthcare setting. Candidemia and candidiasis are fungal infections responsible for high morbidity and mortality among ill patients in hospitals. It is noticeable that prolonged hospital stays lead to a higher economic impact and increased risk for developing secondary fungal or even bacterial infections. New fast and sensitive approaches for the detection of Candida species is highly required. Electrochemical biosensors are an excellent alternative to conventional techniques by combining fast analyte detection, low cost, and the possibility of miniaturization. Lectins are carbohydrate-binding proteins with the capability to reach out to the microorganism cell wall. In this work, we proposed the development of an impedimetric biosensor for Candida spp. based on Concanavalin A (ConA) and wheat germ agglutinin (WGA) as recognition agents of the yeast cells. Atomic force microscopy images indicate changes in the biosensor surface after assembly of the molecules and exposure to fungal samples. Electrochemical impedance spectroscopy results revealed a proportional increase of charge transfer resistance (R CT ) as fungal CFU increased, where four Candida species were evaluated (Candida krusei, Candida tropicalis, Candida parapsilosis and Candida albicans). The biosensor is useful to differentiate Candida spp. with a detection limit between 10 2 to 10 6  CFU mL -1 . The obtained biosensor appears as an innovative candidate for the detection and differentiation of pathogenic Candida spp., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The human papillomavirus (HPV) is one of the main sexually transmitted pathogens that infect the anogenital epithelium and mucous membranes. HPV genotypes can be classified as high and low oncogenic risk, with infection by the former resulting in cervical cancer in approximately 100 % of the cases. In this work, we developed an ultrasensitive electrochemical biosensor for the detection and identification of different HPV genotypes. A nanostructured platform based on a matrix of polyaniline (PANI) containing gold nanoparticles (AuNps) was designed for the chemical immobilization of a DNA probe capable of recognizing different HPV types. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and atomic force microscopy (AFM) were used to characterize the genosensor. The impedimetric responses indicate that the proposed sensor was able to detect HPV (types 6, 11, 16, 31, 33, 45, and 58) in cervical specimens (cDNA samples). We obtained different profiles of electrochemical responses for the high and low-risk HPV genotypes. By adopting a three-dimensional quantitative analysis of impedance response variables, it was possible to identify the existence of a pattern of association for samples of high oncogenic risk, which may lead to the differential diagnosis of HPV. The biosensor demonstrated an excellent analytical performance for the detection of HPV genotypes with high sensibility and selectivity. The genosensor exhibited a linear range of response in the 1 pg μL -1 to 100 pg μL -1 range. Besides, a limit of detection (LOD) of 2.74 pg μL -1 and 7.43 pg μL -1 was obtained for HPV11 and HPV16, respectively, with regression coefficients of 99.88 % and 99.47 %. Thus, the proposed sensor may serve as a good prognostic indicator for patients infected with papillomavirus., Competing Interests: Declaration of Competing Interest The authors declare that there are no competing interests for publication of this paper. Statement, (Copyright © 2020 Elsevier B.V. All rights reserved.)

Arboviruses have been emerging as a significant global health problem due to the recurrent epidemics. Arboviruses require the development of new diagnostic devices due to the nonspecific clinical manifestations. Herein, we report a biosensor based on cysteine (Cys), zinc oxide nanoparticles (ZnONp), and Concanavalin A (ConA) lectin to differentiate between arboviruses infections. ConA is capable of interacting with the saccharide components of the viral capsid. In this study, we evaluated the reproducibility, sensitivity, and specificity of the sensor for the virus of Dengue type 2 (DENV2), Zika (ZIKV), Chikungunya (CHIKV), and Yellow fever (YFV). Atomic force microscopy measurements confirmed the electrode surface modification and revealed a heterogeneous topography during the biorecognition process. Cyclic voltammetry (CV) and impedance spectroscopy (EIS) were used to characterize the biosensor. The blockage of the oxidation-reduction process is related to the formation of Cys-ZnONp-ConA system on the electroactive area and its subsequent interaction with viral glycoproteins. The sensor exhibited a linear response to different concentrations of the studied arboviruses. Our study demonstrates that ConA lectin recognizes the structural glycoproteins of the DENV2, ZIKV, CHIKV, and YFV. DENV2 is the most structurally similar to ZIKV. Our results have shown that the impedimetric response correlates with the structural glycoproteins, as follow: DENV2 (18.6 kΩ) > ZIKV (14.6 kΩ) > CHIKV (6.86 kΩ) > YFV (5.98 kΩ). The homologous structural regions contribute to ConA-arboviruses recognition. Our results demonstrate the use of the proposed system for the development of biosensors for arboviruses infections., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Schistosomiasis is a neglected tropical disease with a worldwide prevalence. Neuroschistosomiasis is the most severe presentation of the disease and affects the central nervous system. In this work, Schistosoma mansoni detection was based on self-assembled layers of 3-mercaptopropyltrimethoxysilane (MPTS) and electrosynthesized gold nanoparticles (AuNPs). The DNA probe was chemisorbed onto AuNPs. The biosensor was characterized by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The impedimetric response of the MPTS-AuNPs-DNA probe system indicates an effective modification of the electrode surface. Topographical atomic force microscopy images were used to characterize the self-assembled layers on the gold electrode surface. The proposed biosystem was able to recognize the S. mansoni genome sequence at different concentrations in samples of urine, cerebrospinal fluid, and serum. Several concentration ranges were evaluated: urine (27-50 pg μL -1 ), cerebrospinal fluid (25-60 pg μL -1 ), and serum (27-42 pg μL -1 ). The limit detection (LOD) of the biosensor was 0.6 pg μL -1 . The developed label-free genosensor was able to detect small concentrations of S. mansoni DNA in complex biological fluids., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Oxazolidine derivatives (OxD) are five ring-membered compounds that contain at least one oxygen and nitrogen in their molecular structure. OxD are known due to several therapeutic activities such as anticancer and antibiotic properties. In this paper, we performed a thermodynamic analysis of the mixed films composed by dipalmitoylphosphatidylglycerol (DPPG), dipalmitoylphosphoethanolamine (DPPE), dipalmitoyl phosphatidylcholine (DPPC) or L-α phosphatidylcholine (PC) with a novel oxazolidine derivate (OxD). Relevant thermodynamic parameters such as excess areas (ΔAE), excess free energies (ΔG), and Gibbs free energy of mixing (AG mix ) were derived from the surface pressure data. The topographical analysis was performed using atomic force microscopy. Based on the calculated values of the thermodynamic parameters, we observed that the miscibility of the mixed films was directly dependent on their composition. DPPG/OxD and DPPE/OxD systems present the best-mixed character at low pressures at OxD molar fraction equivalent to 0.25.

Alkaline phosphatase (ALP) is an enzyme that plays an important role in bone mineralization and skeletal growth. Variations in physiological levels of ALP have been correlated to diseases such as osteomalacia, Paget's disease and arterial calcifications. In this context, the integration of carbon nanotubes (CNT) within osteointegration implants has shown to increase ALP's mineralization activity in virtue of their surface chemistry and their morphological resemblance to collagen nanofibers. In this study we present the development and analytical application of an impedimetric immunosensor based in gold nanoparticle-decorated CNT, which characteristics are desirable in implantable biosensors. The device effectively detects ALP within blood serum, a complex biological fluid where most expressed proteins can be found. Robustness and high sensitivity were attained by immobilizing covalently anti-ALP antibody as a specific probe towards ALP. Cyclic voltammetry, electrochemical impedance spectroscopy and atomic force microscopy were used to characterize the sensor system throughout mounting steps and real sample testing. Impedimetric responses were adjusted to a theoretical electrical circuit and charge transfer resistance showed to be an adequate parameter to evaluate the biorecognition process of the analyte. Additionally, amperometrical current variation and changes in topography found over the surface after positive samples evidenced biorecognition. The final biosensor showed excellent performance with two linear ranges from 0.5 to 50 IU.L -1 and from 100 to 600 IU.L -1 ; limits of detection were calculated as 0.25 and 84.6 IU.L -1 respectively with a relative standard deviation lower than 5%. The device was found to be selective, avoiding protein c, a potential interferer occurring during inflammatory processes. The proposed strategy is promising for osteogenic applications where it can improve osteointegration implants by monitoring ALP activity., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The use of central venous catheters (CVC) is highly associated with nosocomial blood infections and its use largely requires a systematic assessment of benefits and risks. Bacterial contamination of these tubes is frequent and may result in development of microbial consortia also known as biofilm. The woven nature of biofilm provides a practical defense against antimicrobial agents, facilitating bacterial dissemination through the patient's body and development of antimicrobial resistance. In this work, the authors describe the modification of CVC tubing by immobilizing Fe 3 O 4 -aminosilane core-shell nanoparticles functionalized with antimicrobial peptide clavanin A (clavA) as an antimicrobial prophylactic towards Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae. Its anti-biofilm-attachment characteristic relies in clavA natural activity to disrupt the bacterial lipidic membrane. The aminosilane shell prevents iron leaching, which is an important nutrient for bacterial growth. Fe 3 O 4 -clavA-modified CVCs showed to decrease Gram-negative bacteria attachment up to 90% when compared to control clean CVC. Additionally, when hyperthermal treatment is triggered for 5 min at 80 °C in a tubing that already presents bacterial biofilm (CVC-BF), the viability of attached bacteria reduces up to 88%, providing an efficient solution to avoid changing catheter., (Copyright © 2018 Elsevier B.V. All rights reserved.)

An alternative to accelerate the osseointegration on titanium dioxide nanotubes (TNTs) used in osseointegrated implants is through the functionalization of these nanostructured surfaces with biomolecules. In this work, we immobilized a lectin with recognized mitogenic activity, the Cramoll lectin, extracted from Cratylia mollis seeds, on surfaces modified by TNTs. For the immobilization of Cramoll on TNTs surfaces, we used the Layer-by-Layer technique (LbL) by growing five alternate layers of poly(allylamine) hydrochloride (PAH) and poly(acrylic) acid (PAA); lastly we incubated the lectin, at different concentrations, with the TNTs-LbL. Before and after the immobilization procedures, the substrate surfaces were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and, electrochemical impedance spectroscopy (EIS). We also evaluated the Cramoll activity after immobilization on TNTs by using the lectin interaction with ovalbumin. The lectin did not lose its biological activity, even after immobilization onto nanotubular arrays. In addition, we observed an increase osteoblast-like cell adhesion on the TNTs-LbL-Cramoll system when compared to the bare TNTs surfaces. Moreover, a significative cell proliferation was identified on the substrates when Cramoll was immobilized at concentrations of 80, 160 and 320 μg/mL after 48 h of incubation by using the resazurin assay. Our results suggest that Cramoll was efficiently immobilized on a nanotubular array and this new platform presents a great potential to be tested in implantology., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A label-free impedimetric biosensor was developed for determination of BCR/ABL transcripts. Specific DNA primers were covalently immobilized on a gold electrode modified with carboxylated multiwalled carbon nanotubes (cMWCNTs) and zinc oxide nanoparticles (ZnO-NPs). Aggregation of the ZnO-NPs is prevented by the introduction of an amino-modified silica coating, which also allows a subsequent covalent linkage to cMWCNTs. The impedimetric biosensor was typically operated at a working voltage of +10 mV vs. Ag/AgCl, in a frequency range from 100 mHz to 100 kHz. Studies on the surface morphology and electrochemical properties of the electrode demonstrated improved bioactivity. Amperometric currents and impedimetric parameters, such as charge transfer resistance, varied significantly throughout the construction of the biosensor. The hybridization process was also evidenced by changes in the topography of the surface after exposure to samples containing BCR/ABL. The gene sensor has a linear concentration range for the target gene of 6.94 aM to 694 fM with a limit of detection as low as 0.039 aM. Also, the biosensor is selective and reproducible with a standard deviation of 4.1%. Three replicates for each experimental condition were used. Hence, it is perceived to be a viable tool for early-stage diagnosis of the BCR/ABL fusion gene and monitoring of major molecular remission in clinical samples. Graphical abstract Schematic of a highly sensitive hybridization assay for the BCR/ABL fusion gene. It is based on ZnO nanoparticle functionalized with 3-(aminopropyl)triethoxysilane.

Electrical impedance spectroscopy (EIS) appears a promising label-free methodology for the investigation of processes related to the aggregation of macromolecules in solution. Here, we explore the EIS technique as a convenient tool for studying the irreversible aggregation of human insulin and describing its corresponding fibrillation kinetics. The in situ measurement of the electrical response of pure insulin solutions at 60°C allows for the real-time monitoring of the protein fibrillation as a function of the incubation time. The fitting of the EIS data through an equivalent circuit based on a constant phase element provides a simple set of electric parameters whose abrupt changes can be associated to transitions occurring in the organization of the macromolecules. For establishing the reliability of the method proposed, we have compared the protein aggregation profile collected from the EIS data to that obtained from a conventional fluorescence methodology where Thioflavin T (ThT) is used as a dye probe. The description of the fibrillation process is quite similar in both cases, since characteristic times of the same order were found for the consecutive processes associated to the initial lag phase of insulin fibrillation, to the rapid growth of amyloidal aggregates and to the final saturation step. Our results suggest that in situ EIS can be considered as a promising approach for the real-time label-free monitoring of protein fibril formation., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The early diagnosis of breast cancer is crucial for the successful treatment and recovery phases of the patients suffering from the disease. Although mammography is considered the gold standard for diagnosis, it fails to detect some cancers in high-density breasts. In this work, we propose for the first time a tridimensional biosensor platform, to be used on an electrochemical point-of-care device. The bioconjugated platform is constructed on a series of covalent linkages between lectin molecules and a cysteine layer immobilized over gold-coated TiO 2 butterfly-like tridimensional nanomembranes. Through the use of vegetal lectins, we managed to take advantage of the markedly atypical glycomic profile of the cancerous mammalian cell membrane and successfully made a distinction between highly invasive (T47D) and less invasive (MCF7) cancer cell lines. The selectivity of the biosensor was tested by using normal human skin-fibroblast. The proposed cytosensor demonstrated limits of detection as low as 10 cells mL -1 for every cell line and a linear range from 10 to 1.0×10 6 cells mL -1 . Considering that electrochemical impedance values can be correlated with the number of breast cancer cells present in the sample, we suggest that the proposed platform could be useful in facilitating the diagnosis of cancer., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In the last ten years, conjugated polymers started to be used in the immobilization of nucleic acids via non-covalent interactions. In the present study, we describe the construction and use of an electrochemical DNA biosensor based on a nanostructured polyaniline-gold composite, specifically developed for the detection of the BCR/ABL chimeric oncogene. This chromosome translocation is used as a biomarker to confirm the clinical diagnosis of both chronic myelogenous leukemia (CML) and acute lymphocytic leukemia (ALL). The working principle of the biosensor rests on measuring the conductivity resulting from the non-covalent interactions between the hybrid nanocomposite and the DNA probe. The nanostructured platform exhibits a large surface area that enhances the conductivity. Positive cases, which result from the hybridization between DNA probe and targeted gene, induce changes in the amperometric current and in the charge transfer resistance (R CT ) responses. Atomic force microscopy (AFM) images showed changes in the genosensor surface after exposure to cDNA sample of patient with leukemia, evidencing the hybridization process. This new hybrid sensing-platform displayed high specificity and selectivity, and its detection limit is estimated to be as low as 69.4 aM. The biosensor showed excellent analytical performance for the detection of the BCR/ABL oncogene in clinical samples of patients with leukemia. Hence, this electrochemical sensor appears as a simple and attractive tool for the molecular diagnosis of the BCR/ABL oncogene even in early-stage cases of leukemia and for the monitoring of minimum levels of residual disease., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Unusual methods for specific detection of pathogenic bacteria are becoming key points for control and identification of problems related to health and (bio)safety. In this context, this work aims to propose a new approach for the development of nanostructured biosensors based on carbon nanotubes (CNTs) and antimicrobial peptides for bacterial detection. Firstly, the antimicrobial peptide clavanin A (ClavA) was chemically immobilized on CNTs and surface-immobilized ClavA was used to detect Klebsiella pneumoniae, Enterococcus faecalis, Escherichia coli and Bacillus subtilis in a direct assay format. We used electrochemical impedance spectroscopy technique to evaluate the effectiveness and sensitivity of the ClavA-based biosensors by measuring the modifications in their electrochemical responses before and after incubation in presence of different bacteria concentrations. The biosensor was able to discriminate between bacteria concentrations in the 10(2)-10(6)CFU mL(-1) range. Atomic force microscopy analysis confirmed the biosensor functionality for bacterial recognition. This new sensor system was capable of differentiating between Gram-positive and Gram-negative bacteria, since ClavA showed different affinities toward the pathogenic bacteria species., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In this work, a genosensor for the electrochemical detection of genomic DNA from Mycobacterium tuberculosis was developed. The biosensor is based on self-assembled monolayers of mercaptobenzoic acid (MBA) and magnetite nanoparticles (Fe3O4Nps) on bare gold electrode for immobilization of DNA probe. The aim of this work was the development of a platform based on cysteine-coated magnetic Fe3O4Nps linked via the carboxylate group from MBA to the work electrode surface and subsequently to the DNA probe. The probe-genome interaction was evaluated using a [Fe(CN)6](4-)/[Fe(CN)6](3-) redox pair. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to evaluate the bioelectrochemical behavior of the sensor. Atomic force microscopy images showed Fe3O4Nps immobilized across the electrode surface. The interaction of the sensor with different genome DNA concentrations resulted in changes in the charge transfer resistance, indicating a possible use for tuberculosis detection at low concentrations (detection limit of 6ngμL(-1))., (Copyright © 2014 Elsevier Inc. All rights reserved.)