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1.
Antioxidants (Basel) ; 13(6)2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38929084

RESUMEN

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.

2.
AIDS Behav ; 28(8): 2746-2754, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38836986

RESUMEN

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.


Asunto(s)
Infecciones por VIH , Humanos , Infecciones por VIH/prevención & control , Femenino , Masculino , Comunicación , Inteligencia Artificial , Prueba de VIH , Comunicación en Salud/métodos , Conocimientos, Actitudes y Práctica en Salud
3.
Life (Basel) ; 14(2)2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38398743

RESUMEN

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.

4.
Molecules ; 28(16)2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37630267

RESUMEN

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.


Asunto(s)
Ácido Ascórbico , Guayacol , Ácido Glutámico , Polímeros
5.
Plants (Basel) ; 12(12)2023 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-37375897

RESUMEN

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.

6.
Breast Care (Basel) ; 18(2): 141-149, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37261129

RESUMEN

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.

7.
Biochem Biophys Rep ; 34: 101441, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36875795

RESUMEN

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.

9.
Bone Res ; 9(1): 46, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34707086

RESUMEN

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.

10.
Antioxidants (Basel) ; 10(9)2021 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-34573118

RESUMEN

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.

11.
Mediterr J Hematol Infect Dis ; 12(1): e2020056, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32952967

RESUMEN

The purpose of the present review is to give an update regarding the classification, epidemiology, clinical manifestation, diagnoses, and treatment of the Rickettsial diseases present in the Mediterranean area. We performed a comprehensive search, through electronic databases (Pubmed - MEDLINE) and search engines (Google Scholar), of peer-reviewed publications (articles, reviews, and books). The availability of new diagnostic tools, including Polymerase Chain Reaction and nucleotide sequencing has significantly modified the classification of intracellular bacteria, including the order Rickettsiales with more and more new Rickettsia species recognized as human pathogens. Furthermore, emerging Rickettsia species have been found in several countries and are often associated with unique clinical pictures that may challenge the physician in the early detection of the diseases. Rickettsial infections include a wide spectrum of clinical presentations ranging from a benign to a potentially life treating disease that requires prompt recognition and proper management. Recently, due to the spread of SARS-CoV-2 infection, the differential diagnosis with COVID-19 is of crucial importance. The correct understanding of the clinical features, diagnostic tools, and proper treatment can assist clinicians in the management of Rickettsioses in the Mediterranean area.

12.
Molecules ; 25(14)2020 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-32668641

RESUMEN

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.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Bacterias/efectos de los fármacos , Citrus/química , Extractos Vegetales/farmacología , Ácido Ascórbico/análisis , Células CACO-2 , Jugos de Frutas y Vegetales , Humanos , Fenoles/análisis , Especies Reactivas de Oxígeno/metabolismo
13.
Molecules ; 25(11)2020 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-32545293

RESUMEN

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.


Asunto(s)
Inhibidores Enzimáticos/síntesis química , Lacasa/química , Monofenol Monooxigenasa/química , Fenol/química , Propanoles/síntesis química , Tenebrio/crecimiento & desarrollo , Animales , Dominio Catalítico , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Hidroxilación , Lacasa/antagonistas & inhibidores , Lacasa/metabolismo , Modelos Moleculares , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Células PC12 , Propanoles/química , Propanoles/farmacología , Conformación Proteica , Ratas , Tenebrio/efectos de los fármacos , Tenebrio/enzimología
14.
PLoS One ; 14(11): e0224932, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31710629

RESUMEN

A new telemetric system for the electrochemical monitoring of dissolved oxygen is showed. The device, connected with two amperometric sensors, has been successfully applied to the wireless detection of the extracellular oxygen in the central complex of freely-walking Gromphadorhina portentosa. The unit was composed of a potentiostat, a two-channel sensor conditioning circuit, a microprocessor module, and a wireless serial transceiver. The amperometric signals were digitalized and sent to a notebook using a 2.4 GHz transceiver while a serial-to-USB converter was connected to a second transceiver for completing the communication bridge. The software, running on the laptop, allowed to save and graph the oxygen signals. The electronics showed excellent stability and the acquired data was linear in a range comprised between 0 and -165 nA, covering the entire range of oxygen concentrations. A series of experiments were performed to explore the dynamics of dissolved oxygen by exposing the animals to different gases (nitrogen, oxygen and carbon dioxide), to low temperature and anesthetic agents (chloroform and triethylamine). The resulting data are in agreement with previous O2 changes recorded in the brain of awake rats and mice. The proposed system, based on simple and inexpensive components, can constitute a new experimental model for the exploration of central complex neurochemistry and it can also work with oxidizing sensors and amperometric biosensors.


Asunto(s)
Técnicas Biosensibles/instrumentación , Cucarachas/fisiología , Oxígeno/análisis , Tecnología de Sensores Remotos/instrumentación , Animales , Dióxido de Carbono/metabolismo , Cloroformo/metabolismo , Cucarachas/metabolismo , Diseño de Equipo , Etilaminas/metabolismo , Masculino , Nitrógeno/metabolismo , Programas Informáticos , Caminata , Tecnología Inalámbrica
15.
Biosensors (Basel) ; 9(3)2019 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-31366026

RESUMEN

The use of amperometric biosensors has attracted particular attention in recent years, both from researchers and from companies, as they have proven to be low-cost, reliable, and very sensitive devices, with a wide range of uses in different matrices. The continuous development of amperometric biosensors, since their use involves an enzyme, is specifically aimed at keeping and increasing the catalytic properties of the loaded protein, so as to be able to use the same device over time. The present study aimed to investigate the impact of glycerol and polysaccharides, in the presence of polycationic substances to constitute a hydrogel, in enhancing the enzymatic and analytic performance of a glucose biosensor. Initially, it was possible to verify how the deposition of the starch-based hydrogel, in addition to allowing the electropolymerization of the poly(p-phenylenediamine) polymer and the maintenance of its ability to shield the ascorbic acid, did not substantially limit the permeability towards hydrogen peroxide. Moreover, different biosensor designs, loading a mixture containing all the components (alone or in combination) and the enzyme, were tested in order to evaluate the changes of the apparent enzyme kinetic parameters, such as VMAX and KM, and analytical response in terms of Linear Region Slope, highlighting how the presence of all components (starch, glycerol, and polyethyleneimine) were able to substantially enhance the performance of the biosensors. The surface analysis of the biosensors was performed by scanning electron microscope (SEM). More, it was shown that the same performances were kept unchanged for seven days, proving the suitability of this biosensor design for short- and mid-term use.


Asunto(s)
Glucosa/análisis , Glicerol/química , Polisacáridos/química , Técnicas Biosensibles , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Glucosa/química , Hidrogeles/química , Cinética , Polietileneimina , Factores de Tiempo
16.
Biomed Res Int ; 2019: 5641034, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31309107

RESUMEN

Nutraceuticals present in food are molecules able to exert biological activity for the prevention and treatment of various diseases, in form of pharmaceutical preparations, such as capsules, cream, or pills. Myrtus communis L. is a spontaneous Mediterranean evergreen shrub, widely known for the liqueur obtained from its berries rich in phytochemicals such as tannins and flavonoids. In the present study, we aimed to evaluate the properties of myrtle byproducts, residual of the industrial liqueur processing, in Adipose-derived stem cells (ADSCs) induced at oxidative stress by in vitro H2O2 treatment. Cells were exposed for 12-24 and 48h at treatment with extracts and then senescence-induced. ROS production was then determined. The real-time PCR was performed to evaluate the expression of inflammatory cytokines and sirtuin-dependent epigenetic changes, as well the modifications in terms of stem cell pluripotency. The ß-galactosidase assay was conducted to analyze stem cell senescence after treatment. Our results show that industrial myrtle byproducts retain a high antioxidant and antisenescence activity, protecting cells from oxidative stress damages. The results obtained suggest that residues from myrtle liqueur production could be used as resource in formulation of food supplements or pharmaceutical preparations with antioxidant, antiaging, and anti-inflammatory activity.


Asunto(s)
Myrtus/química , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Células Madre/efectos de los fármacos , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Citocinas/metabolismo , Femenino , Flavonoides/farmacología , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Masculino , Persona de Mediana Edad , Especies Reactivas de Oxígeno/metabolismo , Células Madre/metabolismo , Taninos/farmacología , beta-Galactosidasa/metabolismo
17.
Medicina (Kaunas) ; 55(2)2019 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-30743998

RESUMEN

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.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Neoplasias de los Conductos Biliares/genética , Colangiocarcinoma/tratamiento farmacológico , Colangiocarcinoma/genética , Inhibidores Enzimáticos/uso terapéutico , Inmunoterapia , Terapia Molecular Dirigida , Ensayos Clínicos como Asunto , Retroalimentación Fisiológica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Transducción de Señal/efectos de los fármacos , Reparación del Gen Blanco
18.
Sensors (Basel) ; 19(2)2019 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-30669626

RESUMEN

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.


Asunto(s)
Técnicas Biosensibles/métodos , Frío , Glucosa/análisis , Ácido Láctico/análisis , Preservación Biológica , Hielo Seco , Diseño de Equipo , Cinética , Factores de Tiempo
19.
Sci Rep ; 8(1): 11225, 2018 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-30046159

RESUMEN

By identifying endogenous molecules in brain extracellular fluid metabolomics can provide insight into the regulatory mechanisms and functions of sleep. Here we studied how the cortical metabolome changes during sleep, sleep deprivation and spontaneous wakefulness. Mice were implanted with electrodes for chronic sleep/wake recording and with microdialysis probes targeting prefrontal and primary motor cortex. Metabolites were measured using ultra performance liquid chromatography-high resolution mass spectrometry. Sleep/wake changes in metabolites were evaluated using partial least squares discriminant analysis, linear mixed effects model analysis of variance, and machine-learning algorithms. More than 30 known metabolites were reliably detected in most samples. When used by a logistic regression classifier, the profile of these metabolites across sleep, spontaneous wake, and enforced wake was sufficient to assign mice to their correct experimental group (pair-wise) in 80-100% of cases. Eleven of these metabolites showed significantly higher levels in awake than in sleeping mice. Some changes extend previous findings (glutamate, homovanillic acid, lactate, pyruvate, tryptophan, uridine), while others are novel (D-gluconate, N-acetyl-beta-alanine, N-acetylglutamine, orotate, succinate/methylmalonate). The upregulation of the de novo pyrimidine pathway, gluconate shunt and aerobic glycolysis may reflect a wake-dependent need to promote the synthesis of many essential components, from nucleic acids to synaptic membranes.


Asunto(s)
Metabolómica , Corteza Prefrontal/metabolismo , Sueño/fisiología , Vigilia/fisiología , Animales , Ácido Glutámico/metabolismo , Ácido Homovanílico/metabolismo , Humanos , Ácido Láctico/metabolismo , Ratones , Corteza Motora/metabolismo , Corteza Motora/fisiopatología , Corteza Prefrontal/fisiopatología , Ácido Pirúvico/metabolismo , Privación de Sueño/metabolismo , Privación de Sueño/fisiopatología , Triptófano/metabolismo , Uridina/metabolismo
20.
Anal Chem ; 90(10): 6012-6019, 2018 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29658266

RESUMEN

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 ∼60% maximal inhibition toward AChE activity in the clinically relevant concentration range 10-10 000 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.


Asunto(s)
Antineoplásicos/análisis , Técnicas Biosensibles , Neoplasias Colorrectales/tratamiento farmacológico , Técnicas Electroquímicas , Irinotecán/análisis , Acetilcolinesterasa , Oxidorreductasas de Alcohol , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/patología , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Irinotecán/metabolismo , Irinotecán/farmacología , Estructura Molecular , Relación Estructura-Actividad
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