Desarrollo de métodos automáticos de análisis por inyección en flujo multijeringa (MSFIA) para la determinación del ión sulfuro en aguas

Se han desarrollado métodos basados en análisis por inyección en flujo multijeringa (MSFIA) para determinar automáticamente sulfuro en muestras ambientales y aguas residuales, con detección espectrofotométrica previa transformación química del analito (acoplamiento oxidativo del sulfuro con N-N-dimetil-p-fenilendiamina en presencia de Fe(III) para formar azul de metileno). - Sistema MSFIA con difusión gaseosa para aislar el analito de matrices complejas sin ningún pretratamiento manual de la muestra. - Sistema MSFIA con pre-concentración en fase sólida (optrodo de reflectancia difusa sobre disco de membrana) para determinar niveles traza. - Método MSFIA que combina separación y pre-concentración en línea del sulfuro, para ofrecer elevadas selectividad y sensibilidad. - Sistema MSFIA inteligente totalmente automatizado para determinar sulfuro en un amplio rango de concentraciones, capaz de auto-ajustarse sin ninguna intervención del analista. - Estudio comparativo de metodologías en flujo para determinar sulfuro en matrices acuosas. Se discuten críticamente distintas técnicas y sistemas de detección empleados.Multisyringe flow injection analysis (MSFIA) systems for automatic determination of sulfide in environmental and wastewater samples have been developed exploiting spectrophotometric detection prior derivatization of the analyte (oxidative coupling of sulfide with N-N-dimethyl-p-phenylenediamine in presence of Fe(III) to form methylene blue). - A MSFIA system was coupled to gas-diffusion separation to achieve the isolation from complex matrices without any pre-treatment batch sample. - An optrode using disk-based solid-phase extraction in a MSFIA set-up is proposed to determine trace levels. - A hyphenated method that combines the separation and pre-concentration is presented reaching high selectivity and sensitivity. - A fully automated smart MSFIA system for sulfide monitoring in a wide concentration range is proposed choosing by itself the best approach to quantify the analyte without the analyst intervention. - A review of flow-based methodologies for sulfide determination in aqueous matrices is presented. The characteristics of automated protocols using several detection systems are discussed

diagnostic surveillance by candida albicans germ tube antibody in intensive care unit patients

Abstract Background The diagnosis of Invasive Candidiasis (IC) presents serious problems, mainly associated with the absence of pathognomonic symptoms of the disease and the difficulty of isolating the fungus in blood culture. Candida albicans germ tube antibody (CAGTA) provides a rapid and simple test for diagnosis of IC. The aim of this study was to evaluate the diagnostic role of the CAGTA in the monitoring of critically-ill patients at risk of developing IC. Methods During diagnostic surveillance in the intensive care units (ICU) CAGTA was performed twice a week if predetermined risk factors were present and a positive result was considered when a serum titer ≥1/160 was detected in at least one sample. Results Seventy critically ill patients were included in the study. Twenty-three patients with proven/probable IC were identified. The sensitivity, specificity, PPV, and NPV of CAGTA for the diagnosis of proven/probable IC in all 70 patients were 91.3%, 68.1%, 58.3%, and 94.1%, respectively. Statistically significant highest titers were found in patients with proven/probable IC as well as increasing titers more than 1/160. Conclusions Our results suggest that detection of CAGTA could be a useful biomarker for the diagnosis of proven and probable IC in critical patients during prolonged ICU stay. During the monitoring it is opportune to evaluate the titers kinetics since the clinical diagnosis of proven/probable IC coincided with increase titer from negative

Homeotic proteins participate in the function of human-DNA replication origins

Recent evidence points to homeotic proteins as actors in the crosstalk between development and DNA replication. The present work demonstrates that HOXC13, previously identified as a new member of human DNA replicative complexes, is a stable component of early replicating chromatin in living cells: it displays a slow nuclear dynamics due to its anchoring to the DNA minor groove via the arginine-5 residue of the homeodomain. HOXC13 binds in vivo to the lamin B2 origin in a cell-cycle-dependent manner consistent with origin function; the interaction maps with nucleotide precision within the replicative complex. HOXC13 displays in vitro affinity for other replicative complex proteins; it interacts also in vivo with the same proteins in a cell-cycle-dependent fashion. Chromatin-structure modifying treatments, disturbing origin function, reduce also HOXC13–origin interaction. The described interactions are not restricted to a single origin nor to a single homeotic protein (also HOXC10 binds the lamin B2 origin in vivo). Thus, HOX complexes probably contribute in a general, structure-dependent manner, to origin identification and assembly of replicative complexes thereon, in presence of specific chromatin configurations

Curcumin, Hormesis and the Nervous System

Curcumin is a polyphenol compound extracted from the rhizome of Curcuma longa Linn (family Zingiberaceae) commonly used as a spice to color and flavor food. Several preclinical studies have suggested beneficial roles for curcumin as an adjuvant therapy in free radical-based diseases, mainly neurodegenerative disorders. Indeed, curcumin belongs to the family of hormetins and the enhancement of the cell stress response, mainly the heme oxygenase-1 system, is actually considered the common denominator for this dual response. However, evidence-based medicine has clearly demonstrated the lack of any therapeutic effect of curcumin to contrast the onset or progression of neurodegeneration and related diseases. Finally, the curcumin safety profile imposes a careful analysis of the risk/benefit balance prior to proposing chronic supplementation with curcumin

Moringa oleifera Protects SH-SY5YCells from DEHP-Induced Endoplasmic Reticulum Stress and Apoptosis

Moringa oleifera (MO) is a medicinal plant that has been shown to possess antioxidant, anticarcinogenic and antibiotic activities. In a rat model, MO extract (MOe) has been shown to have a protective effect against brain damage and memory decline. As an extending study, here, we have examined the protective effect of MOe against oxidative stress and apoptosis caused in human neuroblastome (SH-SY5Y) cells by di-(2-ethylhexyl) phthalate (DEHP), a plasticizer known to induce neurotoxicity. Our data show that MOe prevents oxidative damage by lowering reactive oxygen species (ROS) formation, restoring mitochondrial respiratory chain complex activities, and, in addition, by modulating the expression of vitagenes, i.e., antioxidant proteins Nrf2 and HO-1. Moreover, MOe prevented neuronal damage by partly inhibiting endoplasmic reticulum (ER) stress response, as indicated by decreased expression of CCAAT-enhancer-binding protein homologous protein (CHOP) and Glucose-regulated protein 78 (GRP78) proteins. MOe also protected SH-SY5Y cells from DEHP-induced apoptosis, preserving mitochondrial membrane permeability and caspase-3 activation. Our findings provide insight into understanding of molecular mechanisms involved in neuroprotective effects by MOe against DEHP damag

Redox modulation by plant polyphenols targeting vitagenes for chemoprevention and therapy: Relevance to novel anti-cancer interventions and mini-brain organoid technology

The scientific community, recently, has focused notable attention on the chemopreventive and therapeutic effects of dietary polyphenols for human health. Emerging evidence demonstrates that polyphenols, flavonoids and vitamins counteract and neutralize genetic and environmental stressors, particularly oxidative stress and inflammatory process closely connected to cancer initiation, promotion and progression. Interestingly, polyphenols can exert antioxidant or pro-oxidant cytotoxic effects depending on their endogenous concentration. Notably, polyphenols at high dose act as pro-oxidants in a wide type of cancer cells by inhibiting Nrf2 pathway and the expression of antioxidant vitagenes, such as NAD(P)H-quinone oxidoreductase (NQO1), glutathione transferase (GT), GPx, heme oxygenase-1 (HO-1), sirtuin-1 (Sirt1) and thioredoxin (Trx) system which play an essential role in the metabolism of reactive oxygen species (ROS), detoxification of xenobiotics and inhibition of cancer progression, by inducing apoptosis and cell cycle arrest according to the hormesis approach. Importantly, mutagenesis of Nrf2 pathway can exacerbate its "dark side" role, representing a crucial event in the initiation stage of carcinogenesis. Herein, we review the hormetic effects of polyphenols and nanoincapsulated-polyphenols in chemoprevention and treatment of brain tumors via activation or inhibition of Nrf2/vitagenes to suppress carcinogenesis in the early stages, and thus inhibit its progression. Lastly, we discuss innovative preclinical approaches through mini-brain tumor organoids to study human carcinogenesis, from basic cancer research to clinical practice, as promising tools to recapitulate the arrangement of structural neuronal tissues and biological functions of the human brain, as well as test drug toxicity and drive personalized and precision medicine in brain cancer

Hydrogen Sulfide and Carnosine: Modulation of Oxidative Stress and Inflammation in Kidney and Brain Axis

Emerging evidence indicates that the dysregulation of cellular redox homeostasis and chronic inflammatory processes are implicated in the pathogenesis of kidney and brain disorders. In this light, endogenous dipeptide carnosine (β-alanyl-L-histidine) and hydrogen sulfide (H2S) exert cytoprotective actions through the modulation of redox-dependent resilience pathways during oxidative stress and inflammation. Several recent studies have elucidated a functional crosstalk occurring between kidney and the brain. The pathophysiological link of this crosstalk is represented by oxidative stress and inflammatory processes which contribute to the high prevalence of neuropsychiatric disorders, cognitive impairment, and dementia during the natural history of chronic kidney disease. Herein, we provide an overview of the main pathophysiological mechanisms related to high levels of pro-inflammatory cytokines, including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and neurotoxins, which play a critical role in the kidney–brain crosstalk. The present paper also explores the respective role of H2S and carnosine in the modulation of oxidative stress and inflammation in the kidney–brain axis. It suggests that these activities are likely mediated, at least in part, via hormetic processes, involving Nrf2 (Nuclear factor-like 2), Hsp 70 (heat shock protein 70), SIRT-1 (Sirtuin-1), Trx (Thioredoxin), and the glutathione system. Metabolic interactions at the kidney and brain axis level operate in controlling and reducing oxidant-induced inflammatory damage and therefore, can be a promising potential therapeutic target to reduce the severity of renal and brain injuries in humans

Profiling the Volatile and Non-Volatile Compounds along with the Antioxidant Properties of Malted Barley

In this work, the stability of antioxidant compounds in malting barley seeds before and after the production of the final products is reported. In this reflection, the findings revealed that the process of fermentation had a significant impact on antioxidant activity. In vitro, antioxidant capacities were evaluated using DPPH free radical scavenging assay. The results obtained from the spectrophotometric analysis showed that the lowest inhibition value was observed in the samples that were obtained by the classical fermentation process (ABC) and the samples of non-alcoholic beer obtained by the thermal process (NABT), with free radical inhibition capacity values of 8.50% and 5.50%, respectively. The samples of hopped wort (HW) and malted barley seeds extract (BSE) showed very high antioxidant activity with free radical inhibition capacity of 14% and 12.60%, respectively. The obtained extracts were analyzed by gas chromatography and high-performance liquid chromatography, both combined with mass spectrometry detection (GC-MS, HPLC-MS). GC-MS analysis of the SPME extraction showed the presence of 29 compounds with isopentyl alcohol in major concentration (18.19%) in the alcoholic beer; on the other hand, the HPLC-DAD-ESI/MS analysis of the ethyl acetate extract showed the presence of 13 phenolic compounds. Interestingly, the degradation of 3-Hydroxyphloretin 2'-O-glucoside in the final products of the non-alcoholic beers was found. Finally, the FTIR analysis was also employed in order to detect the type of efficient groups present in the extracts

Evaluación de agentes enmascarantes para abatir interferencias en la determinación de plomo por generación de hidruros-fluorescencia atómica

La determinación de plomo mediante la generación de hidruros-fluorescencia atómica (HG-AFS) presenta el problema de interferencias. Con el objetivo de minimizarlas, el efecto de agentes enmascarantes (MA) como KI, L-cisteína y 1,10-fenantrolina fue estudiado en ausencia y presencia de especies interferentes (As, Cr, Cu y Fe). Las mediciones de plomo fueron realizadas a través de la técnica HG-AFS. La linealidad de las curvas de calibración no fue afectada por la adición de los MA. El KI en la solución reductora disminuyó las interferencias de concentraciones de As y Cu. 1,10-phentrolina mostró un buen efecto sobre la interferencia por As. El Cr y Cu fueron los interferentes más serios. El fierro no ocasionó ninguna interferencia en los experimentos. Se estableció el límite tolerable máximo para cada uno de los iones interferentes. La precisión del método analítico fue probada mediante la determinación de niveles traza de plomo en un material de referencia certificado (BCR-610, agua de pozo) y la adición de KI como MA.The greatest problem with the Pb-determination by hydride generation (HG) technique is the interference from foreign ions present in matrix samples. In order to minimize these interferences, the effect of masking agents such as KI, L-cysteine and 1,10-phenanthroline was studied in absence and in presence of selected interfering species (As, Cr, Cu and Fe). The Pb-determinations were performed by HG-AFS system. The linearity of calibration graphs was not affected by the addition of the MA. The use of KI in the reducing solution, diminishes interferences from concentrations of As and Cu. 1,10-phenanthroline showed a positive effect on the interference by As. Moreover, Cr and Cu appeared to be the most serious interfering ions. Fe not presented any interference in the experiments. It was established the maximum tolerated level of the foreign ion tested in presence of MA. The accuracy in the determination of lead at trace levels in BCR-610 (groundwater) certified reference material was reached using KI as MA

Perinatal Parenting Stress, Anxiety, and Depression Outcomes in First-Time Mothers and Fathers: A 3- to 6-Months Postpartum Follow-Up Study

Objective: Although there is an established link between parenting stress, postnatal depression, and anxiety, no study has yet investigated this link in first-time parental couples. The specific aims of this study were 1) to investigate whether there were any differences between first-time fathers’ and mothers’ postnatal parenting stress, anxiety, and depression symptoms and to see their evolution between three and 6 months after their child’s birth; and 2) to explore how each parent’s parenting stress and anxiety levels and the anxiety levels and depressive symptoms of their partners contributed to parental postnatal depression. Method: The sample included 362 parents (181 couples; mothers’ MAge = 35.03, SD = 4.7; fathers’ MAge = 37.9, SD = 5.6) of healthy babies. At three (T1) and 6 months (T2) postpartum, both parents filled out, in a counterbalanced order, the Parenting Stress Index-Short Form, the Edinburgh Postnatal Depression Scale, and the State- Trait Anxiety Inventory. Results: The analyses showed that compared to fathers, mothers reported higher scores on postpartum anxiety, depression, and parenting stress. The scores for all measures for both mothers and fathers decreased from T1 to T2. However, a path analysis suggested that the persistence of both maternal and paternal postnatal depression was directly influenced by the parent’s own levels of anxiety and parenting stress and by the presence of depression in his/her partner. Discussion: This study highlights the relevant impact and effects of both maternal and paternal stress, anxiety, and depression symptoms during the transition to parenthood. Therefore, to provide efficacious, targeted, early interventions, perinatal screening should be directed at both parents