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With the advancement of artificial intelligence(AI), platforms like ChatGPT have gained traction in different fields, including Medicine. This study aims to evaluate the potential of ChatGPT in addressing questions related to HIV prevention and to assess its accuracy, completeness, and inclusivity. A team consisting of 15 physicians, six members from HIV communities, and three experts in gender and queer studies designed an assessment of ChatGPT. Queries were categorized into five thematic groups: general HIV information, behaviors increasing HIV acquisition risk, HIV and pregnancy, HIV testing, and the prophylaxis use. A team of medical doctors was in charge of developing questions to be submitted to ChatGPT. The other members critically assessed the generated responses regarding level of expertise, accuracy, completeness, and inclusivity. The median accuracy score was 5.5 out of 6, with 88.4% of responses achieving a score ≥ 5. Completeness had a median of 3 out of 3, while the median for inclusivity was 2 out of 3. Some thematic groups, like behaviors associated with HIV transmission and prophylaxis, exhibited higher accuracy, indicating variable performance across different topics. Issues of inclusivity were identified, notably the use of outdated terms and a lack of representation for some communities. ChatGPT demonstrates significant potential in providing accurate information on HIV-related topics. However, while responses were often scientifically accurate, they sometimes lacked the socio-political context and inclusivity essential for effective health communication. This underlines the importance of aligning AI-driven platforms with contemporary health communication strategies and ensuring the balance of accuracy and inclusivity.
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Infecções por HIV , Humanos , Infecções por HIV/prevenção & controle , Feminino , Masculino , Comunicação , Inteligência Artificial , Teste de HIV , Comunicação em Saúde/métodos , Conhecimentos, Atitudes e Prática em SaúdeRESUMO
Polymeric permselective films are frequently used for amperometric biosensors to prevent electroactive interference present in the target matrix. Phenylenediamines are the most commonly used for the deposition of shielding polymeric films against interfering species; however, even phenolic monomers have been utilized in the creation of these films for microsensors and biosensors. The purpose of this paper is to evaluate the performances of electrosynthesized polymers, layered by means of constant potential amperometry (CPA), of naturally occurring compound zingerone (ZING) and its dimer dehydrozingerone (ZING DIM), which was obtained by straight oxidative coupling reaction. The polymers showed interesting shielding characteristics against the main interfering species, such as ascorbic acid (AA): actually, polyZING exhibited an AA shielding aptitude comprised between 77.6 and 99.6%, comparable to that obtained with PPD. Moreover, a marked capability of increased monitoring of hydrogen peroxide (HP), when data were compared with bare metal results, was observed. In particular, polyZING showed increases ranging between 55.6 and 85.6%. In the present work, the molecular structures of the obtained polymers have been theorized and docking analyses were performed to understand their peculiar characteristics better. The structures were docked using the Lamarckian genetic algorithm (LGA). Glutamate biosensors based on those polymers were built, and their performances were compared with biosensors based on PPD, which is the most widespread polymer for the construction of amperometric biosensors.
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Ácido Ascórbico , Guaiacol , Ácido Glutâmico , PolímerosRESUMO
The impaired activity of tyrosinase and laccase can provoke serious concerns in the life cycles of mammals, insects and microorganisms. Investigation of inhibitors of these two enzymes may lead to the discovery of whitening agents, medicinal products, anti-browning substances and compounds for controlling harmful insects and bacteria. A small collection of novel reversible tyrosinase and laccase inhibitors with a phenylpropanoid and hydroxylated biphenyl core was prepared using naturally occurring compounds and their activity was measured by spectrophotometric and electrochemical assays. Biosensors based on tyrosinase and laccase enzymes were constructed and used to detect the type of protein-ligand interaction and half maximal inhibitory concentration (IC50). Most of the inhibitors showed an IC50 in a range of 20-423 nM for tyrosinase and 23-2619 nM for laccase. Due to the safety concerns of conventional tyrosinase and laccase inhibitors, the viability of the new compounds was assayed on PC12 cells, four of which showed a viability of roughly 80% at 40 µM. In silico studies on the crystal structure of laccase enzyme identified a hydroxylated biphenyl bearing a prenylated chain as the lead structure, which activated strong and effective interactions at the active site of the enzyme. These data were confirmed by in vivo experiments performed on the insect model Tenebrio molitur.
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Inibidores Enzimáticos/síntese química , Lacase/química , Monofenol Mono-Oxigenase/química , Fenol/química , Propanóis/síntese química , Tenebrio/crescimento & desenvolvimento , Animais , Domínio Catalítico , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Hidroxilação , Lacase/antagonistas & inibidores , Lacase/metabolismo , Modelos Moleculares , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Células PC12 , Propanóis/química , Propanóis/farmacologia , Conformação Proteica , Ratos , Tenebrio/efeitos dos fármacos , Tenebrio/enzimologiaRESUMO
Pompia is a Citrus species belonging to Sardinian endemic biodiversity. Health benefits were attributed to its flavedo rind extracts and essential oils while the juice qualities have never been investigated. In this paper, the antioxidant, antimicrobial, and other biological properties of Pompia juice were studied. A combined LCMS/electrochemical/biological approach was used to clarify a still debated phylogeny of this species and to explain the role of its juice phenolic compounds. A closer phylogenetic relationship with lemon and citron, rather than oranges was suggested. Sensors-based electrochemical measures, together with LCMS qualitative and quantitative analyses, revealed a high contribution of ascorbic acid and phenolics with low redox potential, isorhamnetin 3-O-rutinoside, diosmin, and diosmetin 6,8-diglucoside, to antioxidant capacity. The biological assays demonstrated a marked effect of low concentration of Pompia juice against reactive oxygen species (ROS) starting from 50 µg mL-1, and a moderate capacity to reduce ROS damages on cell membrane. Treatments with Pompia juice also resulted in a significant reduction (20%) of the metabolic activity of SW48 colon cancer cells. Lastly, MIC, MBC, and MBIC antimicrobial assays demonstrated that Pompia and lemon juices have inhibitory and antibiofilm effects against the pathogenic bacteria Pseudomonas aeruginosa, Streptococcus aureus, and Enterococcus faecalis.
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Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Citrus/química , Extratos Vegetais/farmacologia , Ácido Ascórbico/análise , Células CACO-2 , Sucos de Frutas e Vegetais , Humanos , Fenóis/análise , Espécies Reativas de Oxigênio/metabolismoRESUMO
Molecular biomarkers are very important in biology, biotechnology and even in medicine, but it is quite hard to convert biology-related signals into measurable data. For this purpose, amperometric biosensors have proven to be particularly suitable because of their specificity and sensitivity. The operation and shelf stability of the biosensor are quite important features, and storage procedures therefore play an important role in preserving the performance of the biosensors. In the present study two different designs for both glucose and lactate biosensor, differing only in regards to the containment net, represented by polyurethane or glutharaldehyde, were studied under different storage conditions (+4, -20 and -80 °C) and monitored over a period of 120 days, in order to evaluate the variations of kinetic parameters, as VMAX and KM, and LRS as the analytical parameter. Surprisingly, the storage at -80 °C yielded the best results because of an unexpected and, most of all, long-lasting increase of VMAX and LRS, denoting an interesting improvement in enzyme performances and stability over time. The present study aimed to also evaluate the impact of a short-period storage in dry ice on biosensor performances, in order to simulate a hypothetical preparation-conservation-shipment condition.
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Técnicas Biossensoriais/métodos , Temperatura Baixa , Glucose/análise , Ácido Láctico/análise , Preservação Biológica , Gelo-Seco , Desenho de Equipamento , Cinética , Fatores de TempoRESUMO
Cholangiocarcinoma (CCA) is a highly-aggressive malignancy arising from the biliary tree, characterized by a steady increase in incidence globally and a high mortality rate. Most CCAs are diagnosed in the advanced and metastatic phases of the disease, due to the paucity of signs and symptoms in the early stages. This fact, along with the poor results of the local and systemic therapies currently employed, is responsible for the poor outcome of CCA patients and strongly supports the need for novel therapeutic agents and strategies. In recent years, the introduction of next-generation sequencing technologies has opened new horizons for a better understanding of the genetic pathophysiology of CCA and, consequently, for the identification and evaluation of new treatments tailored to the molecular features or alterations progressively elucidated. In this review article, we describe the potential targets under investigation and the current molecular therapies employed in biliary tract cancers. In addition, we summarize the main drugs against CCA under evaluation in ongoing trials and describe the preliminary data coming from these pioneering studies.
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Antineoplásicos Imunológicos/uso terapêutico , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/genética , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , Inibidores Enzimáticos/uso terapêutico , Imunoterapia , Terapia de Alvo Molecular , Ensaios Clínicos como Assunto , Retroalimentação Fisiológica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Transdução de Sinais/efeitos dos fármacos , Reparo Gênico Alvo-DirigidoRESUMO
Therapeutic drug monitoring (TDM) is the clinical practice of measuring pharmaceutical drug concentrations in patients' biofluids at designated intervals, thus allowing a close and timely control of their dosage. To date, TDM in oncology can only be performed by trained personnel in centralized laboratories and core facilities employing conventional analytical techniques (e.g., MS). CPT-11 is an antineoplastic drug that inhibits topoisomerase type I, causing cell death, and is widely used in the treatment of colorectal cancer. CPT-11 was also found to directly inhibit acetylcholine esterase (AChE), an enzyme involved in neuromuscular junction. In this work, we describe an enzymatic biosensor, based on AChE and choline oxidase (ChOx), which can quantify CPT-11. ACh (acetylcholine) substrate is converted to choline, which is subsequently metabolized by ChOx to give betaine aldehyde and hydrogen peroxide. The latter one is then oxidized at a suitably polarized platinum electrode, providing a current transient proportional to the amount of ACh. Such an enzymatic process is hampered by CPT-11. The biosensor showed a â¼60% maximal inhibition toward AChE activity in the clinically relevant concentration range 10-10â¯000 ng/mL of CPT-11 in both simple (phosphate buffer) and complex (fetal bovine serum) matrixes, while its metabolites showed negligible effects. These findings could open new routes toward a real-time TDM in oncology, thus improving the therapeutic treatments and lowering the related costs.
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Antineoplásicos/análise , Técnicas Biossensoriais , Neoplasias Colorretais/tratamento farmacológico , Técnicas Eletroquímicas , Irinotecano/análise , Acetilcolinesterase , Oxirredutases do Álcool , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Irinotecano/metabolismo , Irinotecano/farmacologia , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Adipose-derived stem cells (ADSCs) represent one of the cellular populations resident in adipose tissue. They can be recruited under certain stimuli and committed to become preadipocytes, and then mature adipocytes. Controlling stem cell differentiation towards the adipogenic phenotype could have a great impact on future drug development aimed at counteracting fat depots. Stem cell commitment can be influenced by different molecules, such as melatonin, which we have previously shown to be an osteogenic inducer. Here, we aimed at evaluating the effects elicited by melatonin, even in the presence of vitamin D, on ADSC adipogenesis assessed in a specific medium. The transcription of specific adipogenesis orchestrating genes, such as aP2, peroxisome proliferator-activated receptor γ (PPAR-γ), and that of adipocyte-specific genes, including lipoprotein lipase (LPL) and acyl-CoA thioesterase 2 (ACOT2), was significantly inhibited in cells that had been treated in the presence of melatonin and vitamin D, alone or in combination. Protein content and lipid accumulation confirmed a reduction in adipogenesis in ADSCs that had been grown in adipogenic conditions, but in the presence of melatonin and/or vitamin D. Our findings indicate the role of melatonin and vitamin D in deciding stem cell fate, and disclose novel therapeutic approaches against fat depots.
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Adipogenia/efeitos dos fármacos , Tecido Adiposo/citologia , Células-Tronco Adultas/citologia , Antioxidantes/farmacologia , Melatonina/farmacologia , Vitamina D/farmacologia , Vitaminas/farmacologia , Adulto , Células-Tronco Adultas/efeitos dos fármacos , Células-Tronco Adultas/metabolismo , Células Cultivadas , Feminino , Humanos , Metabolismo dos Lipídeos , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Masculino , Pessoa de Meia-Idade , PPAR gama/genética , PPAR gama/metabolismo , Tioléster Hidrolases/genética , Tioléster Hidrolases/metabolismoRESUMO
Enzyme-based chemical biosensors are based on biological recognition. In order to operate, the enzymes must be available to catalyze a specific biochemical reaction and be stable under the normal operating conditions of the biosensor. Design of biosensors is based on knowledge about the target analyte, as well as the complexity of the matrix in which the analyte has to be quantified. This article reviews the problems resulting from the interaction of enzyme-based amperometric biosensors with complex biological matrices containing the target analyte(s). One of the most challenging disadvantages of amperometric enzyme-based biosensor detection is signal reduction from fouling agents and interference from chemicals present in the sample matrix. This article, therefore, investigates the principles of functioning of enzymatic biosensors, their analytical performance over time and the strategies used to optimize their performance. Moreover, the composition of biological fluids as a function of their interaction with biosensing will be presented.
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Técnicas Biossensoriais/métodos , Líquidos Corporais/química , Enzimas/análiseRESUMO
A new carbon ascorbate oxidase-based sensor-biosensor system (SB) was coupled to a dual-channel telemetric device for online simultaneous electrochemical detection of ascorbic acid (AA) and antioxidant capacity in Hamlin, Sanguinello, and Moro orange varieties. The electrocatalytic performances of the SB were investigated by cyclic voltammetry and amperometric techniques. The phenol composition of orange juice of each variety, and the cyclic voltammetries of the most represented phenols, were provided. The in vitro calibrations were performed in PBS (pH 5.6), applying a constant potential of +500 mV. A standard mixture of phenols, based on orange juice composition, was used as reference material for studying SB behavior. SB works at an applied potential of +500 mV, in a concentration range comprised between the LOD 0.26 µM and 20 µM. In this concentration range, limiting the data acquisition time to 2 min, the problems of electrode passivation due to phenols polymerization were overcome. AA calibration showed that the biosensor registered statistically lower currents than the sensor since the enzyme oxidized AA before it reached the electrode surface. Standard mixture calibration showed that currents registered by sensor and biosensor did not statistically differ. The difference between sensor and biosensor AA registered currents was used to calculate an AA selectivity index and, consequently, to determine the AA content and the antioxidant capacity in the juices. The novelty of the SB is its ability to distinguish between AA and phenols contribution to antioxidant capacity. The obtained results were in accordance with reference methods.
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Antioxidantes/análise , Ascorbato Oxidase/metabolismo , Ácido Ascórbico/análise , Bebidas/análise , Técnicas Biossensoriais/métodos , Tecnologia de Alimentos/instrumentação , Tecnologia de Alimentos/métodos , Ascorbato Oxidase/química , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas , Eletrodos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Oxirredução , Fenóis/análise , Telemetria/instrumentaçãoRESUMO
Until now, research has been performed mainly in men, with a low recruitment of women; consequentially, biological, physiological, and physio-pathological mechanisms are less understood in women. Obviously, without data obtained on women, it is impossible to apply the results of research appropriately to women. This issue also applies to medical devices (MDs), and numerous problems linked to scarce pre-market research and clinical trials on MDs were evidenced after their introduction to the market. Globally, some MDs are less efficient in women than in men and sometimes MDs are less safe for women than men, although recently there has been a small but significant decrease in the sex and gender gap. As an example, cardiac resynchronization defibrillators seem to produce more beneficial effects in women than in men. It is also important to remember that MDs can impact the health of healthcare providers and this could occur in a sex- and gender-dependent manner. Recently, MDs' complexity is rising, and to ensure their appropriate use they must have a sex-gender-sensitive approach. Unfortunately, the majority of physicians, healthcare providers, and developers of MDs still believe that the human population is only constituted by men. Therefore, to overcome the gender gap, a real collaboration between the inventors of MDs, health researchers, and health providers should be established to test MDs in female and male tissues, animals, and women.
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Oxidative stress, an imbalance between reactive oxygen species (ROS) and endogenous antioxidants, plays an important role in the development of neurodegenerative diseases, including Parkinson's. The human brain is vulnerable to oxidative stress because of the high rate of oxygen that it needs and the high levels of polyunsaturated fatty acids, which are substrates of lipid peroxidation. Natural antioxidants inhibit oxidation and reduce oxidative stress, preventing cancer, inflammation, and neurodegenerative disorders. Furthermore, in the literature, it is reported that antioxidants, due to their possible neuroprotective activity, may offer an interesting option for better symptom management, even Parkinson's disease (PD). Natural antioxidants are usually found in several foods, such as fruits, vegetables, meat, fish, and oil, and in food wastes, such as seeds, peels, leaves, and skin. They can help the system of endogenous antioxidants, protect or repair cellular components from oxidative stress, and even halt lipid, protein, and DNA damage to neurons. This review will examine the extent of knowledge from the last ten years, about the neuroprotective potential effect of natural antioxidants present in food and food by-products, in in vivo and in vitro PD models. Additionally, this study will demonstrate that the pool of dietary antioxidants may be an important tool in the prevention of PD and an opportunity for cost savings in the public health area.
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The present paper aims to miniaturize a graphite-epoxy and synthetic zeolite-modified graphite-epoxy composite macroelectrode as a quasi-microelectrode aiming in vitro and also, envisaging in vivo simultaneous electrochemical detection of dopamine (DA) and ascorbic acid (AA) neurotransmitters, or DA detection in the presence of AA. The electrochemical behavior and the response of the designed materials to the presence of dopamine and ascorbic acid without any protective membranes were studied by cyclic voltammetry and constant-potential amperometry techniques. The catalytic effect towards dopamine detection was proved for the synthetic zeolite-modified graphite-epoxy composite quasi-microelectrode, allowing increasing the sensitivity and selectivity for this analyte detection, besides a possible electrostatic attraction between dopamine cation and the negative surface of the synthetic zeolite and electrostatic repulsion with ascorbic acid anion. Also, the synthetic zeolite-modified graphite-epoxy composite quasi-microelectrode gave the best electroanalytical parameters for dopamine detection using constant-potential amperometry, the most useful technique for practical applications.
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Ácido Ascórbico/análise , Dopamina/análise , Técnicas Eletroquímicas , Compostos de Epóxi/química , Grafite/química , Zeolitas/química , MicroeletrodosRESUMO
Ethyl alcohol may be considered one of the most widespread central nervous system (CNS) depressants in Western countries. Because of its toxicological and neurobiological implications, the detection of ethanol in brain extracellular fluid (ECF) is of great importance. In a previous study, we described the development and characterization of an implantable biosensor successfully used for the real-time detection of ethanol in the brain of freely-moving rats. The implanted biosensor, integrated in a low-cost telemetry system, was demonstrated to be a reliable device for the short-time monitoring of exogenous ethanol in brain ECF. In this paper we describe a further in-vitro characterization of the above-mentioned biosensor in terms of oxygen, pH and temperature dependence in order to complete its validation. With the aim of enhancing ethanol biosensor performance, different enzyme loadings were investigated in terms of apparent ethanol Michaelis-Menten kinetic parameters, viz. IMAX, KM and linear region slope, as well as ascorbic acid interference shielding. The responses of biosensors were studied over a period of 28 days. The overall findings of the present study confirm the original biosensor configuration to be the best of those investigated for in-vivo applications up to one week after implantation.
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Técnicas Biossensoriais/instrumentação , Química Encefálica , Etanol/análise , Modelos Teóricos , Próteses e Implantes , Animais , Técnicas Biossensoriais/métodos , Enzimas/metabolismo , Concentração de Íons de Hidrogênio , Oxigênio , Ratos , TemperaturaRESUMO
Background: Experimental evidence indicates that Naloxone (NLX) holds antioxidant properties. The present study aims at verifying the hypothesis that NLX could prevent oxidative stress induced by hydrogen peroxide (H2O2) in PC12 cells. Methods: To investigate the antioxidant effect of NLX, initially, we performed electrochemical experiments by means of platinum-based sensors in a cell-free system. Subsequently, NLX was tested in PC12 cells on H2O2-induced overproduction of intracellular levels of reactive-oxygen-species (ROS), apoptosis, modification of cells' cycle distribution and damage of cells' plasma membrane. Results: This study reveals that NLX counteracts intracellular ROS production, reduces H2O2-induced apoptosis levels, and prevents the oxidative damage-dependent increases of the percentage of cells in G2/M phase. Likewise, NLX protects PC12 cells from H2O2- induced oxidative damage, by preventing the lactate dehydrogenase (LDH) release. Moreover, electrochemical experiments confirmed the antioxidant properties of NLX. Conclusion: Overall, these findings provide a starting point for studying further the protective effects of NLX on oxidative stress.
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According to the WHO, the overall age-standardized cancer rate keeps declining, and the number of cases diagnosed each year increases, remaining among the leading causes of death in 91 out of 172 recorded countries. In this context, novel cancer prediction and therapeutic protocols are compulsory. The effect of a Stachys circinata L'Hér dichloromethane extract (ScDME) on cell redox homeostasis and tumor proliferation was investigated. HepG2 cell feedback mechanisms to oxidative stress exposure were evaluated by determining catalase (CAT) and reduced glutathione (GSH), following the supply with ScDME (0.0-5.7 µg/µL). Cytotoxicity of ScDME against the human umbilical vein endothelial cell (HUVEC) and two human cancer cell lines (breast: MCF7; liver: HepG2) was evaluated by the MTT assay. H2O2-stressed HepG2 cells supplied with the S. circinata extracts exhibited significantly increased CAT and GSH activity as compared to unsupplied ones. The anti-inflammatory activity of the extracts was evaluated by real time-qPCR on IL-1, IL-6 and TNF-α expression. As a result, this research points out that S. circinata dichloromethane extract owns anti-inflammatory and anti-proliferative properties against MCF7 and HepG2 cells and activates CAT and GSH of the HepG2 cells' antioxidant enzyme system.
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Background: Cancer cases diagnosed each year are increasing, mainly because the population is ageing and, in part, due to early detection. This implies that there are more and more persons that receive medical anticancer therapies and that are interested in maintaining their quality of life. Many oncological treatments, including chemotherapy, immunotherapy, surgery, and radiotherapy, and combined therapy are associated with cutaneous toxicity and long-term side effects to different tissues and organs. This is particularly relevant when new therapies are used since these may cause new and unexpected side effects that may be short-lived but, in some cases, may become chronic or permanent. Patients often seek advice with their oncologists on what can be done and what cannot be done. Notably, many of the cutaneous side effects can be prevented or reduced by adequate interventions. Summary: The aim of this review is to highlight how oncological patients may benefit from a closer collaboration between specialists in different branches. We will focus on women with breast cancer since we think that they may derive a special benefit from this collaboration, but we will analyse other cancers in future papers. Key Messages: The working group was created to help the medical doctor in the prevention and management of all the adverse effects of the oncological treatments, supporting patients in this phase of their life, including nutritional assessment and dietary support.
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Ethanol is one of the most widespread psychotropic agents in western society. While its psychoactive effects are mainly associated with GABAergic and glutamatergic systems, the positive reinforcing properties of ethanol are related to activation of mesolimbic dopaminergic pathways resulting in a release of dopamine in the nucleus accumbens. Given these neurobiological implications, the detection of ethanol in brain extracellular fluid (ECF) is of great importance. In this study, we describe the development and characterization of an implantable biosensor for the amperometric detection of brain ethanol in real time. Ten different designs were characterized in vitro in terms of Michaelis-Menten kinetics (V(MAX) and K(M)), sensitivity (linear region slope, limit of detection (LOD), and limit of quantification (LOQ)), and electroactive interference blocking. The same parameters were monitored in selected designs up to 28 days after fabrication in order to quantify their stability. Finally, the best performing biosensor design was selected for implantation in the nucleus accumbens and coupled with a previously developed telemetric device for the real-time monitoring of ethanol in freely moving, untethered rats. Ethanol was then administered systemically to animals, either alone or in combination with ranitidine (an alcohol dehydrogenase inhibitor) while the biosensor signal was continuously recorded. The implanted biosensor, integrated in the low-cost telemetry system, was demonstrated to be a reliable device for the short-time monitoring of exogenous ethanol in brain ECF and represents a new generation of analytical tools for studying ethanol toxicokinetics and the effect of drugs on brain ethanol levels.
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Técnicas Biossensoriais/instrumentação , Encéfalo/metabolismo , Eletrodos Implantados , Etanol/metabolismo , Movimento , Telemetria/instrumentação , Animais , Encéfalo/efeitos dos fármacos , Eletroquímica , Etanol/administração & dosagem , Etanol/farmacologia , Limite de Detecção , Masculino , Ranitidina/farmacologia , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
This work provides companies in the fresh-cut produce sector with an Ascorbate Bluetooth© Analyzer (ABA), a screen-printed sensor-based device for ascorbic acid (AA) detection, for quality control all along the supply chain. The amperometric detection of AA on fresh and fresh-cut parsley, under correct and incorrect storage temperature, allowed us to investigate the kinetics of AA decay in response to oxidative stress. The role of ascorbate oxidase (AOx) and ascorbate peroxidase (APx) was studied. ABA was used in situ by unskilled personnel. Treatments influenced AA decay kinetics, which were linear in fresh parsley, and non-linear in fresh-cut. Two hours at 28 °C immediately after chopping, the resilience of the fresh-cut parsley was reduced, even though the cold chain was restored. Two hours at -2 °C caused a rapid loss of AA until its complete decay after 72 h. Significant differences between treatments were observed in both the expression and activity of AOx and APx. ABA registered sudden changes of parsley AA following unpredicted variations of temperature during processing or transport. It was useful to remedy the effects of unexpected flaws in the cold chain, which can be proposed for quality preservation of different fresh-cut produce.
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Tissue engineering is rapidly progressing toward clinical application. In the musculoskeletal field, there has been an increasing necessity for bone and cartilage replacement. Despite the promising translational potential of tissue engineering approaches, careful attention should be given to the quality of developed constructs to increase the real applicability to patients. After a general introduction to musculoskeletal tissue engineering, this narrative review aims to offer an overview of methods, starting from classical techniques, such as gene expression analysis and histology, to less common methods, such as Raman spectroscopy, microcomputed tomography, and biosensors, that can be employed to assess the quality of constructs in terms of viability, morphology, or matrix deposition. A particular emphasis is given to standards and good practices (GXP), which can be applicable in different sectors. Moreover, a classification of the methods into destructive, noninvasive, or conservative based on the possible further development of a preimplant quality monitoring system is proposed. Biosensors in musculoskeletal tissue engineering have not yet been used but have been proposed as a novel technology that can be exploited with numerous advantages, including minimal invasiveness, making them suitable for the development of preimplant quality control systems.