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1.
Int J Mol Sci ; 25(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38612890

RESUMO

The endoplasmic reticulum maintains proteostasis, which can be disrupted by oxidative stress, nutrient deprivation, hypoxia, lack of ATP, and toxicity caused by xenobiotic compounds, all of which can result in the accumulation of misfolded proteins. These stressors activate the unfolded protein response (UPR), which aims to restore proteostasis and avoid cell death. However, endoplasmic response-associated degradation (ERAD) is sometimes triggered to degrade the misfolded and unassembled proteins instead. If stress persists, cells activate three sensors: PERK, IRE-1, and ATF6. Glioma cells can use these sensors to remain unresponsive to chemotherapeutic treatments. In such cases, the activation of ATF4 via PERK and some proteins via IRE-1 can promote several types of cell death. The search for new antitumor compounds that can successfully and directly induce an endoplasmic reticulum stress response ranges from ligands to oxygen-dependent metabolic pathways in the cell capable of activating cell death pathways. Herein, we discuss the importance of the ER stress mechanism in glioma and likely therapeutic targets within the UPR pathway, as well as chemicals, pharmaceutical compounds, and natural derivatives of potential use against gliomas.


Assuntos
Estresse do Retículo Endoplasmático , Glioma , Humanos , Resposta a Proteínas não Dobradas , Retículo Endoplasmático , Glioma/tratamento farmacológico , Preparações Farmacêuticas
2.
J Chromatogr A ; 1688: 463689, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36528901

RESUMO

Capillary gel electrophoresis (CGE) has been widely used for analysis of proteins according to their size. However, to our knowledge, this technique has not been optimized to immunoglobulin A (IgA) analysis, a protein of current and emerging high interest in several fields. IgA is the first barrier of human body against pathogens. This protein in human milk and colostrum is essential for immune protection of newborns and treatment of milk for storage in Human Milk Banks may alter IgA. The emerging use of IgA as therapeutic treatment also encourages the development of analysis methods for this class of immunoglobulins. IgA is far more heterogeneously glycosylated and complex than the well-studied IgG molecules. IgA in serum is mainly monomeric (mIgA) with about 160 kDa, while in secretions such as saliva, milk, colostrum, etc, secretory immunoglobulin A (sIgA) is the predominant form. This is a dimer where both monomers are linked by the J-chain and the secretory component accounting all together for a MW higher than 400 kDa including the glycans. This size is far from the 225 kDa MW for which commercial CGE kits are intended. The general rules governing CGE behavior of analytes cannot be directly applied to every protein. Addressing studies directed specifically to target proteins is specially needed for the large size and highly complex target analytes of this study. In this work the effect of several factors on CGE analysis of human serum and colostrum IgA is studied. The feasibility of performing analysis of both IgA classes using a commercial CGE kit is shown. In addition, this work introduces another novelty by preparing tailor-made reproducible gel buffers and to characterize them in terms of dynamic viscosity, conductivity, and electroosmotic flow mobility in bare fused silica capillaries. The possibility of analyzing mIgA and sIgA in less than 10 min using these tailor-made gels is demonstrated. Inter-day variation (RSD) for the main peak of sIgA is 0.25% for migration time (tm) and 0.27% for percentage corrected peak area (Acorr).


Assuntos
Capilares , Imunoglobulina A Secretora , Recém-Nascido , Feminino , Gravidez , Humanos , Imunoglobulina A Secretora/análise , Peso Molecular , Capilares/química , Imunoglobulina A , Colostro/química , Leite Humano/química , Glicoproteínas , Eletroforese Capilar
3.
BJA Open ; 6: 100140, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37588176

RESUMO

Background: Intraoperative hypotension is associated with organ injury. Current intraoperative arterial pressure management is mainly reactive. Predictive haemodynamic monitoring may help clinicians reduce intraoperative hypotension. The Acumen™ Hypotension Prediction Index software (HPI-software) (Edwards Lifesciences, Irvine, CA, USA) was developed to predict hypotension. We built up the European multicentre, prospective, observational EU HYPROTECT Registry to describe the incidence, duration, and severity of intraoperative hypotension when using HPI-software monitoring in patients having noncardiac surgery. Methods: We enrolled 749 patients having elective major noncardiac surgery in 12 medical centres in five European countries. Patients were monitored using the HPI-software. We quantified hypotension using the time-weighted average MAP <65 mm Hg (primary endpoint), the proportion of patients with at least one ≥1 min episode of a MAP <65 mm Hg, the number of ≥1 min episodes of a MAP <65 mm Hg, and duration patients spent below a MAP of 65 mm Hg. Results: We included 702 patients in the final analysis. The median time-weighted average MAP <65 mm Hg was 0.03 (0.00-0.20) mm Hg. In addition, 285 patients (41%) had no ≥1 min episode of a MAP <65 mm Hg; 417 patients (59%) had at least one. The median number of ≥1 min episodes of a MAP <65 mm Hg was 1 (0-3). Patients spent a median of 2 (0-9) min below a MAP of 65 mm Hg. Conclusions: The median time-weighted average MAP <65 mm Hg was very low in patients in this registry. This suggests that using HPI-software monitoring may help reduce the duration and severity of intraoperative hypotension in patients having noncardiac surgery.

4.
J Clin Med ; 11(19)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36233455

RESUMO

Background: Intraoperative hypotension is common in patients having non-cardiac surgery and associated with postoperative acute myocardial injury, acute kidney injury, and mortality. Avoiding intraoperative hypotension is a complex task for anesthesiologists. Using artificial intelligence to predict hypotension from clinical and hemodynamic data is an innovative and intriguing approach. The AcumenTM Hypotension Prediction Index (HPI) software (Edwards Lifesciences; Irvine, CA, USA) was developed using artificial intelligence­specifically machine learning­and predicts hypotension from blood pressure waveform features. We aimed to describe the incidence, duration, severity, and causes of intraoperative hypotension when using HPI monitoring in patients having elective major non-cardiac surgery. Methods: We built up a European, multicenter, prospective, observational registry including at least 700 evaluable patients from five European countries. The registry includes consenting adults (≥18 years) who were scheduled for elective major non-cardiac surgery under general anesthesia that was expected to last at least 120 min and in whom arterial catheter placement and HPI monitoring was planned. The major objectives are to quantify and characterize intraoperative hypotension (defined as a mean arterial pressure [MAP] < 65 mmHg) when using HPI monitoring. This includes the time-weighted average (TWA) MAP < 65 mmHg, area under a MAP of 65 mmHg, the number of episodes of a MAP < 65 mmHg, the proportion of patients with at least one episode (1 min or more) of a MAP < 65 mmHg, and the absolute maximum decrease below a MAP of 65 mmHg. In addition, we will assess causes of intraoperative hypotension and investigate associations between intraoperative hypotension and postoperative outcomes. Discussion: There are only sparse data on the effect of using HPI monitoring on intraoperative hypotension in patients having elective major non-cardiac surgery. Therefore, we built up a European, multicenter, prospective, observational registry to describe the incidence, duration, severity, and causes of intraoperative hypotension when using HPI monitoring in patients having elective major non-cardiac surgery.

5.
Neuroscience ; 507: 79-98, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36370934

RESUMO

Gut dysbiosis is considered a risk factor for Parkinson's disease (PD), and chronic treatment with probiotics could prevent it. Here we report the assessment of a probiotic mixture [Lacticaseibacillus rhamnosus GG (LGG), and Bifidobacterium animalis lactis BB-12 (BB-12)] administered to male rats 2 weeks before and 3 weeks after injecting 6-hydroxydopamine (6-OHDA) into the right striatum, a model that mimics the early stages of PD. Before and after lesion, animals were subjected to behavioral tests: narrow beam, cylinder test, and apomorphine (APO)-induced rotations. Dopaminergic (DA) denervation and microglia recruitment were assessed with tyrosine hydroxylase (TH+) and ionized calcium-binding protein-1 adapter (Iba1+) immunostaining, respectively. Post 6-OHDA injury, rats treated with sunflower oil (probiotics vehicle) developed significant decrease in crossing speed and increases in contralateral paw slips (narrow beam), forepaw use asymmetry (cylinder), and APO-induced rotations. In striatum, 6-OHDA eliminated ≈2/3 of TH+ area and caused significant increase of Iba1+ microglia population. Retrograde axonal degeneration suppressed ≈2/5 of TH+ neurons in the substantia nigra pars compacta (SNpc). In hemiparkinsonian rats, probiotics treatment significantly improved the crossing speed, and also reduced paw slips (postlesion days 14 and 21), the loss of TH+ neurons in SNpc, and the loss of TH+ area and of Iba1+ microglia count in striatum, without affecting the proportion of microglia morphological phenotypes. Probiotics treatment did not attenuate forepaw use asymmetry nor APO-induced rotations. These results indicate that the mixture of probiotics LGG and BB-12 protects nigrostriatal DA neurons against 6-OHDA-induced damage, supporting their potential as preventive treatment of PD.


Assuntos
Bifidobacterium animalis , Lacticaseibacillus rhamnosus , Transtornos Motores , Doença de Parkinson , Probióticos , Ratos , Masculino , Animais , Oxidopamina , Bifidobacterium animalis/metabolismo , Doença de Parkinson/patologia , Microglia/metabolismo , Lacticaseibacillus , Substância Negra/metabolismo , Transtornos Motores/patologia , Corpo Estriado/metabolismo , Neurônios Dopaminérgicos/metabolismo , Dopamina , Apomorfina/farmacologia , Tirosina 3-Mono-Oxigenase/metabolismo , Probióticos/farmacologia
6.
Food Res Int ; 140: 110066, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33648289

RESUMO

Blueberries (BB) are rich in antioxidant polyphenols, and their intake could prevent Parkinson's disease (PD). Here we assessed whether rats chronically fed dried raw BB develop resistance to dopaminergic denervation and motor disorders caused by unilateral intrastriatal injection of 6-hydroxydopamine (6-OHDA), a dopaminergic neurotoxin acting mainly by inducing oxidative stress. Male rats were fed either with LabDiet® alone or supplemented with 3% lyophilized raw BB for 2 weeks before and 3 weeks after injecting 6-OHDA (day 0) or vehicle (mock lesion) into the right striatum. The cylinder test was performed on days -14, -7, -1, +7, +14, and +21; the percentage of ipsilateral forepaw (IF) use asymmetry was determined by counting the wall contacts made with either forepaw or with both. Apomorphine (0.25 mg/kg, s.c.)-induced rotation was performed on days -1, +7, +14, and +21. Full contralateral rotations were counted in 3-min periods, every 15 min, up to 90 min. Striatal slices were immunostained for tyrosine hydroxylase (TH) and the ionized calcium-binding protein-1 adapter (Iba1) [immunoreactive area or microglia count in right striatum expressed as % of the left striatum]. Antioxidants in BB methanolic extracts neutralized the free radical 2,2-diphenyl-1-picrylhydrazyl in a concentration-dependent manner. Anthocyanins have been reported as the most abundant polyphenols in BB. Using the pH differential method, the total anthocyanin content (malvidin-3-glucoside equivalents) in raw BB averaged 21.04 mg/g dry weight. The range of anthocyanin intake by rats throughout the study varied from 37.7 to 72.2 mg/kg body weight. The time and food type factors, as well as their interaction were significant according to two-way RM-ANOVA in both the apomorphine-induced rotations and the cylinder test. Compared with LabDiet® alone, chronic supplementation with 3% dried raw BB decreased apomorphine-induced rotations on days +14 and +21 (p < 0.001) and produced a 46% reduction in total rotations post-surgery (p < 0.05), but only caused a partial, non-significant, decrease of IF asymmetry. BB supplementation reduced TH loss in the striatum (p < 0.05) but did not attenuate the increase of Iba1+ microglia. The consumption of 3% dried raw blueberries attenuates dopaminergic denervation and partially reverses motor disorders in the 6-OHDA-induced PD model in rats. The phytochemicals of raw blueberries that contribute to the observed neuroprotective effect are yet to be identified.


Assuntos
Apomorfina , Mirtilos Azuis (Planta) , Animais , Apomorfina/farmacologia , Corpo Estriado , Masculino , Oxidopamina , Ratos , Substância Negra
7.
Integr Zool ; 13(3): 267-279, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29168606

RESUMO

Synchrony between seed growth and oogenesis is suggested to largely shape trophic breadth of seed-feeding insects and ultimately to contribute to their co-existence by means of resource partitioning or in the time when infestation occurs. Here we investigated: (i) the role of seed phenology and sexual maturation of females in the host specificity of seed-feeding weevils (Curculio spp.) predating in hazel and oak mixed forests; and (ii) the consequences that trophic breadth and host distribution have in the genetic structure of the weevil populations. DNA analyses were used to establish unequivocally host specificity and to determine the population genetic structure. We identified 4 species with different specificity, namely Curculio nucum females matured earlier and infested a unique host (hazelnuts, Corylus avellana) while 3 species (Curculio venosus, Curculio glandium and Curculio elephas) predated upon the acorns of the 2 oaks (Quercus ilex and Quercus pubescens). The high specificity of C. nucum coupled with a more discontinuous distribution of hazel trees resulted in a significant genetic structure among sites. In addition, the presence of an excess of local rare haplotypes indicated that C. nucum populations went through genetic expansion after recent bottlenecks. Conversely, these effects were not observed in the more generalist Curculio glandium predating upon oaks. Ultimately, co-existence of weevil species in this multi-host-parasite system is influenced by both resource and time partitioning. To what extent the restriction in gene flow among C. nucum populations may have negative consequences for their persistence in a time of increasing disturbances (e.g. drought in Mediterranean areas) deserves further research.


Assuntos
Oogênese , Sementes/crescimento & desenvolvimento , Gorgulhos/genética , Animais , Corylus , Código de Barras de DNA Taxonômico , Feminino , Florestas , Haplótipos , Herbivoria , Dispersão Vegetal , Quercus , Espanha , Especificidade da Espécie
8.
Sci Total Environ ; 592: 326-333, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28319719

RESUMO

Phytofiltration lagoons are phytoremediation technologies suitable for tropical and sub-tropical regions requiring cost-effective and echo-friendly technologies. A biorefinery of fourth generation has been implemented at pilot plant level in Xalapa, Mexico, and the phytofiltration lagoon, being the first module for provision of treated water and plant biomass for biofuel production plays a key role. The aim of this work was to evaluate the performance of such phytofiltration lagoon with a working volume of 13,000 L for the removal of nutrients from an urban river polluted with domestic wastewater and the biomass productivity of the macrophyte Pistia stratiotes, during five different experimental periods, comprising 42 days each one. The maximum absolute growth rates (AGR, gdwday-1) registered for P. stratiotes during the Aug-Oct '15 and the March-Apr '16 and Apr-May '16 period were in the range of 13.51±2.66 to 16.54±2.02gdwday-1. The average biomass productivity was 5.808gdwm-2day-1. Productivities were similar during the periods of Aug-Oct '15, Mar-Apr '16 and Apr-May '16 and significantly higher (p<0.05) than those registered in Oct-Nov '15 and Jan-Feb '16. Removal percentages of COD and nutrients varied according to the season. COD was in the range of 47.82±39.3% to 88.00±15.0%. Ammonium N was in the range of 76.78±21% to 98.79±0.9%. Nitrates were removed in the range of 16.92±64%. to 97.14±4.5%. Finally, phosphates were removed very effectively, from 73.72±18.5% to 92.89±4.3%. A hydraulic retention time of 7 days was enough for the effective treatment of the water from the polluted river. It was concluded that the phytofiltration lagoon with P. stratiotes is very feasible within the biorefinery for providing biomass year-round and for treating the polluted water very effectively.


Assuntos
Araceae , Biodegradação Ambiental , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água , México , Águas Residuárias
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