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1.
Mar Environ Res ; 202: 106727, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39244954

RESUMEN

The use of pyrethroids in aquaculture has been an important component of achieving a thriving salmon farming industry in Chile. While the residual presence of such substances is known to depend on environmental conditions, most ecotoxicological studies to date have not considered environmental context. Here, we conducted oceanographic monitoring combined with experiments aiming to estimate the effects of two pyrethroids on the feeding rates of larvae of farmed mussels, Mytilus chilensis. In additional experiments, mussel spats were exposed to both pyrethroids, but under contrasting temperature/pH so as to mimic winter and summer conditions. Experiments mimicking spring conditions revealed that both pyrethroid substances affected the feeding of mussel larvae as a function of concentration. Conversely, significant impact of pyrethroids on adults were not observed with regard to temperature and pH, but a significant impact of low temperature/low pH condition on ingestion rates was confirmed. Given the current status of increasing ocean acidification, the results of this study are expected to provide useful information with regard to achieving sustainable mussel aquaculture, especially considering both activities occur in similar geographic areas, and the expansion of salmon farming areas is ongoing in Chile.

2.
Clin Ophthalmol ; 18: 2439-2451, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39233999

RESUMEN

Background: This research aims to investigate the influence of environmental factors on the treatment efficacy of ocular lubricants in patients from urban areas with dry eye disease (DED). Methods: A phase IV clinical trial, which included 173 patients from major cities in Mexico, was randomly assigned to use ocular lubricants four times a day for 30 days. Ocular Surface Disease Index (OSDI), noninvasive tear film break-up time (NIBUT), ocular staining, and conjunctival hyperemia (CH) among other factors like weather, and air pollution as covariates were analysed. Results: After 30 days, OSDI score decreased by 14.8 points (p<0.001), and NIBUT increased by 2.9 seconds (p< 0.001), with longer values observed in patients recruited in autumn and winter (additional 1.8 seconds, p< 0.05) compared to those recruited in spring. Patients living in cities with cooler weather and high humidity, but low air quality had higher OSDI and conjunctival stain scores of up to 4.4 and 0.3 points, respectively, as compared to those living in cities with similar pollution and humidity levels but with higher temperatures (p-values= 0.019 and 0.050). Patients with moderate CH had an increase of up to 0.8 points in their corneal stain score (p< 0.010). We also found that ozone levels were related to the predicted changes in OSDI and NIBUT. Conclusion: This study demonstrated the impact of environmental factors on the signs and symptoms of DED and suggests that patients residing in cities with inadequately controlled air pollution can benefit from using ocular lubricants to alleviate their symptoms. Trial Registration: Trial is registered at clinicaltrials.gov (NCT04702776).

3.
Dalton Trans ; 53(36): 14995-15009, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39076042

RESUMEN

Developing and investigating advanced multifunctional materials with magnetic properties as candidates for assembling spin qubits for quantum computing is imperative. A new polytopic ligand based on oxamate and aniline was used to promote the synthesis of three neutral homometallic lanthanide-coordinated polymers. New complexes with the formula {Ln(phox)3(DMSO)2(H2O)}n, where Ln = Eu3+ (1), Gd3+ (2), and Tb3+ (3) [phox = N-(phenyl)oxamate and DMSO = dimethylsulfoxide], were synthesized and well characterized by spectroscopic methods as well as X-ray crystallographic analysis. All crystalline structures comprise neutral zigzag chains. The lanthanide ions are linked by three phox ligands, in which two oxygen atoms from two different ligands are responsible for connecting the trivalent lanthanide ions, and one phox ligand completes the coordination sphere in a bis-bidentate mode, together with two DMSO molecules and one water coordination molecule. The coordination sphere of lanthanide ions consisted of spherical capped square antiprism (CSAPR-9) symmetry. The magnetic properties of 1-3 were investigated in the 2-300 K temperature range. The dynamic (ac) magnetic properties of 2 reveal a frequency dependence involving the phonon bottleneck mechanism below 33 K under nonzero applied dc magnetic fields, resulting in an example of a field-induced single-molecule magnet. Solid-state photophysical measurements for Eu3+ (1) and Tb3+ (3) complexes indicate that the N-(phenyl)oxamate ligands are very efficient in sensitizing the lanthanide(III) ions in the visible region of the electromagnetic spectrum. Compounds 1 and 3 exhibited an emission in the red and green regions, respectively. Experimental results and theoretical calculations using the Sparkle/RM1 method support a quantum efficiency of ∼72% for 1, suggesting its potential as a candidate for light conversion molecular devices (LCMDs).

4.
Environ Toxicol Chem ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38629594

RESUMEN

We evaluated the main leaching indices that have been used for decades for the protection of groundwater against contamination by pesticides. We describe the index classifications in detail and discuss their advantages and limitations relative to their prediction value. Most of the indices have similarities in the types of parameters they use. Some of the similarities are basic physicochemical properties of the pesticides such as their water solubility and their organic carbon partition coefficient, as well as characteristics such as environmental persistence in the soil and some soil characteristics. It is very difficult to maintain a simple index with high predictive power. However, comparisons are allowed by many indices among different active ingredients before pesticides are classified according to the risk of being groundwater contaminants. In contrast, limitations are the scarce inclusion of pesticide byproducts in the ground, lack of prediction capacity for polar pesticides, and lack of prediction of the vulnerability of groundwater to being contaminated by pesticides. Despite the limitations of such approaches, they are of great utility, particularly for protection of groundwater from pesticide contamination when little information is available, which is the case in most developing countries and in countries with economies in transition. Caution is recommended in the analysis of information generated by these approximations, which ideally should be validated experimentally in the different application scenarios and the needs for pesticide assessment based on local information. Environ Toxicol Chem 2024;00:1-14. © 2024 SETAC.

5.
Chemistry ; 30(33): e202400680, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38593232

RESUMEN

Supramolecular metallogels combine the rheological properties of gels with the color, magnetism, and other properties of metal ions. Lanthanide ions such as Eu(III) can be valuable components of metallogels due to their fascinating luminescence. In this work, we combine Eu(III) and iminodiacetic acid (IDA) into luminescent hydrogels. We investigate the tailoring of the rheological properties of these gels by changes in their metal:ligand ratio. Further, we use the highly sensitive Eu(III) luminescence to obtain information about the chemical structure of the materials. In special, we take advantage of computational calculations to employ an indirect method for structural elucidation, in which the simulated luminescent properties of candidate structures are matched to the experimental data. With this strategy, we can propose molecular structures for different EuIDA gels. We also explore the usage of these gels for the loading of bioactive molecules such as OXA, observing that its aldose reductase activity remains present in the gel. We envision that the findings from this work could inspire the development of luminescent hydrogels with tunable rheology for applications such as 3D printing and imaging-guided drug delivery platforms. Finally, Eu(III) emission-based structural elucidation could be a powerful tool in the characterization of advanced materials.


Asunto(s)
Europio , Hidrogeles , Europio/química , Hidrogeles/química , Luminiscencia , Iminoácidos/química , Reología , Sustancias Luminiscentes/química , Ligandos , Geles/química
6.
J Texture Stud ; 55(2): e12831, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38613314

RESUMEN

To ensure the best quality bread, it is important to consider the speed of digestion of starch and proteins, as well as how time fermentation and storage time influence the rate of starch digestion and the texture of the bread. This study compared the effect of fermentation time and days of storage on the texture, physicochemical, protein and starch digestibility of sourdough bread. Texture profile analysis showed that the fermentation time in recently baked sourdough bread affects hardness, chewiness, and springiness. The electrophoretic profile showed a decrease in band thickness with increase in fermentation time, consistent with a higher percentage of protein digestion. While fermentation time did not significantly affect rapidly digestible starch (RDS) and slowly digestible starch (SDS), storage time resulted in a decrease in RDS and an increase in SDS. Sourdough breads had higher levels of resistant starch (RS). The digestibility characteristics of protein and starch, as well as texture properties, are significantly influenced by fermentation and storage time. The evidence suggests that sourdough bread has the potential to improve the digestion of protein and to effectively regulate the glycemic response, which is due to its higher levels of SDS and RS.


Asunto(s)
Pan , Almidón , Hidrólisis , Fermentación , Almidón Resistente , Digestión
7.
Arch Microbiol ; 206(3): 128, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38416227

RESUMEN

This study was carried out to investigate the use of different substrates for the production of Escovopsis conidia and verify the virulence of four different isolates cultured on four types of substrates using a novel bioassay. Escovopsis isolates were molecularly identified, based on Internal Transcribed Spacer (ITS) nucleotide sequences. To evaluate conidial production, suspensions (1 × 106 conidia mL-1) of each Escovopsis isolate were inoculated onto four substrates (parboiled rice, white rice, rolled oats, and corn grits). After 14 days, conidial yields were assessed. The virulence of each isolate cultured on the four substrates was tested against Leucoagaricus fungus garden fragments, by directly applying 500 µL of each conidial suspension (1 × 107 conidia mL-1), and the development of the parasite was monitored daily until it completely colonized the fungus garden. It was observed that rolled oats were the best substrate for conidial production, with a yield of 1.7 × 107 to 2.0 × 108 conidia mL-1. Furthermore, isolate AT-01 produced the highest number of conidia when compared with the other isolates. Regardless of the substrate used to produce AT-01 conidia, this isolate completely colonized the fungus garden 6 days post inoculation (dpi), followed by AT-02, AC-01, and AC-2. High levels of both conidial production and virulence against the leaf-cutting ant fungus garden were observed here.


Asunto(s)
Agaricales , Hormigas , Hypocreales , Oryza , Parásitos , Animales , Esporas Fúngicas , Jardines , Agentes de Control Biológico , Grano Comestible , Zea mays
9.
Appl Microbiol Biotechnol ; 107(11): 3699-3716, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37083969

RESUMEN

Fungal colorants are gradually entering the global color market, given their advantages of being less harmful to human health, as well as having greater stability and biotechnological potential, compared to other natural sources. The present work concerns the isolation and identification of an endophytic filamentous fungus, together with the chemical characterization and assessment of the fluorescence, toxicity, stability, and application potential of its synthesized red colorant. The endophytic fungus was isolated from Hymenaea courbaril, a tree from the Brazilian savannah, and was identified as Talaromyces minnesotensis by phenotypic and genotypic characterization. Submerged cultivation of the fungus resulted in the production of approximately 12 AU500 of a red biocolorant which according to LC-DAD-MS analysis is characterized by being a complex mixture of molecules of the azaphilone class. Regarding cytotoxicity assays, activity against human hepatoblastoma (HepG2) cells was only observed at concentrations above 5.0 g L-1, while antimicrobial effects against pathogenic bacteria and yeast occurred at concentrations above 50.0 g L-1. The biocolorant showed high stability at neutral pH values and low temperatures (10 to 20 °C) and high half-life values (t1/2), which indicates potential versatility for application in different matrices, as observed in tests using detergent, gelatin, enamel, paint, and fabrics. The results demonstrated that the biocolorant synthesized by Talaromyces minnesotensis has potential for future biotechnological applications. KEY POINTS: • An endophytic fungus, which was isolated and identified, synthesize a red colorant. • The colorant showed fluorescence property, low toxicity, and application potential. • The red biocolorant was highly stable at pH 8.0 and temperatures below 20°C.


Asunto(s)
Talaromyces , Humanos , Temperatura , Frío , Alimentos , Concentración de Iones de Hidrógeno , Saccharomyces cerevisiae
10.
Int J Biol Macromol ; 227: 83-92, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36535350

RESUMEN

This research aims to find the optimal conditions for the encapsulation of anthocyanin extract using taro starch to increase the retention of active compounds (RAC), drying yield (DY), antioxidant activity, stability, and bioaccessibility. The microencapsulation is carried out in a spray dryer, and the process is optimized using response surface method (RSM), applying starch concentration and inlet air temperature as independent parameters. Optimized microcapsules (OM) are obtained with solids concentration of 20.9 % and inlet temperature of 125 °C as optimal conditions. Drying yield (70.1 %), moisture content (5.2 %), water activity (0.211), phenolic compound content (797.8 mg GAE/g), anthocyanins (469.4 mg CE3G/g), ABTS (116.2 mg AAE/g) and DPPH (104.4 mg AAE/g) are analyzed through RSM. Retention percentage in OM show values of 60 % in bioactive compounds up to four weeks of storage under accelerated storage conditions. Bioaccessibility of OM is 10 % higher than that observed in the extract without encapsulation during gastrointestinal digestion. The results in this study show that OM made with taro starch and obtained with RSM effectively protect through digestion and ensure bioactive compound stability during storage.


Asunto(s)
Colocasia , Almidón , Almidón/química , Antocianinas/química , Fenoles/química , Desecación
12.
Front Pharmacol ; 13: 963736, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36324671

RESUMEN

Acridine derivatives have been found with anticancer and antinociceptive activities. Herein, we aimed to evaluate the toxicological, antitumor, and antinociceptive actions of N'-(6-chloro-2-methoxyacridin-9-yl)-2-cyanoacetohydrazide (ACS-AZ), a 9-aminoacridine derivative with antimalarial activity. The toxicity was assessed by acute toxicity and micronucleus tests in mice. The in vivo antitumor effect of ACS-AZ (12.5, 25, or 50 mg/kg, intraperitoneally, i.p.) was determined using the Ehrlich tumor model, and toxicity. The antinociceptive efficacy of the compound (50 mg/kg, i.p.) was investigated using formalin and hot plate assays in mice. The role of the opioid system was also investigated. In the acute toxicity test, the LD50 (lethal dose 50%) value was 500 mg/kg (i.p.), and no detectable genotoxic effect was observed. After a 7-day treatment, ACS-AZ significantly (p < 0.05) reduced tumor cell viability and peritumoral microvessels density, suggesting antiangiogenic action. In addition, ACS-AZ reduced (p < 0.05) IL-1ß and CCL-2 levels, which may be related to the antiangiogenic effect, while increasing (p < 0.05) TNF-α and IL-4 levels, which are related to its direct cytotoxicity. ACS-AZ also decreased (p < 0.05) oxidative stress and nitric oxide (NO) levels, both of which are crucial mediators in cancer known for their angiogenic action. Moreover, weak toxicological effects were recorded after a 7-day treatment (biochemical, hematological, and histological parameters). Concerning antinociceptive activity, ACS-AZ was effective on hotplate and formalin (early and late phases) tests (p < 0.05), characteristic of analgesic agents with central action. Through pretreatment with the non-selective (naloxone) and µ1-selective (naloxonazine) opioid antagonists, we observed that the antinociceptive effect of ACS-AZ is mediated mainly by µ1-opioid receptors (p < 0.05). In conclusion, ACS-AZ has low toxicity and antitumoral activity related to cytotoxic and antiangiogenic actions that involve the modulation of reactive oxygen species, NO, and cytokine levels, in addition to antinociceptive properties involving the opioid system.

13.
Pharmaceuticals (Basel) ; 15(9)2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36145320

RESUMEN

In this study, we report the synthesis of twenty new acridine-thiosemicarbazone derivatives and their antiproliferative activities. Mechanisms of action such as the inhibition of topoisomerase IIα and the interaction with DNA have been studied for some of the most active derivatives by means of both in silico and in vitro methods, and evaluations of the non-clinical toxicities (in vivo) in mice. In general, the compounds showed greater cytotoxicity against B16-F10 cells, with the highest potency for DL-08 (IC50 = 14.79 µM). Derivatives DL-01 (77%), DL-07 (74%) and DL-08 (79%) showed interesting inhibition of topoisomerase IIα when compared to amsacrine, at 100 µM. In silico studies proposed the way of bonding of these compounds and a possible stereoelectronic reason for the absence of enzymatic activity for CL-07 and DL-06. Interactions with DNA presented different spectroscopic effects and indicate that the compound CL-07 has higher affinity for DNA (Kb = 4.75 × 104 M-1; Ksv = 2.6 × 103 M-1). In addition, compounds selected for non-clinical toxicity testing did not show serious signs of toxicity at the dose of 2000 mg/kg in mice; cytotoxic tests performed on leukemic cells (K-562) and its resistant form (K-562 Lucena 1) identified moderate potency for DL-01 and DL-08, with IC50 between 11.45 and 17.32 µM.

14.
Lupus ; 31(13): 1639-1648, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36123774

RESUMEN

BACKGROUND: Patients with systemic lupus erythematosus (SLE) have an increased cardiovascular (CV) risk. Insulin resistance (IR), which is higher in patients with SLE, adversely impacts left ventricular (LV) remodeling and function. The aims were to determine LV dysfunction and evaluate the influence of potential risk factors on subclinical LV dysfunction in women with SLE, including IR. METHODS: This cross-sectional study included adult women with SLE without diabetes mellitus (DM), hypertension or severe obesity. Diastolic dysfunction (DD) was verified according to current guidelines. Insulin resistance was estimated using the Quantose score. RESULTS: We included 77 women. The frequency of IR was 65%. All participants had a normal ejection fraction (EF), and 11 (15.7%) had abnormal LV global longitudinal strain (GLS). Twenty-three (32.8%) had DD. The GLS% and global circumferential strain (GCS)% did not differ in patients with and without IR (-20.8 ± 3.1 vs -20.5 ± 2.1; p = 0.61 and -27.9 ± 4.4 vs -27.4 ± 3.7; p = 0.57, respectively). The prevalence of DD was 38.1% in patients with IR versus 25% in those without (p = 0.30). E/e' and E/A ratios did not differ between groups (6.6 ± 1.9 vs 6.6 ± 1.5; p = 0.98 and 1.3 ± 0.3 vs 1.3 ± 0.2; p = 0.27). Higher BMI (OR: 1.2, 95% CI 1.1-1.5) and disease duration (OR: 1.2, 95% CI 1.1-1.4) were associated with DD. CONCLUSIONS: Patients with overweight/obesity may be at higher risk of LV dysfunction. Although IR was high in our patients with SLE was not associated with systolic dysfunction or DD. Body mass index and disease duration were associated with an increased risk of DD.


Asunto(s)
Resistencia a la Insulina , Lupus Eritematoso Sistémico , Disfunción Ventricular Izquierda , Humanos , Adulto , Femenino , Índice de Masa Corporal , Estudios Transversales , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/epidemiología , Disfunción Ventricular Izquierda/epidemiología , Disfunción Ventricular Izquierda/etiología , Remodelación Ventricular , Función Ventricular Izquierda , Volumen Sistólico
15.
Front Pharmacol ; 13: 1003264, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36160442

RESUMEN

Background: There is abundant ethnopharmacological evidence the uses of regarding Solanum species as antitumor and anticancer agents. Glycoalkaloids are among the molecules with antiproliferative activity reported in these species. Purpose: To evaluate the anticancer effect of the Solanum glycoalkaloid tomatine in hepatocellular carcinoma (HCC) in vitro (HepG2 cells) and in vivo models. Methods: The resazurin reduction assay was performed to detect the effect of tomatine on cell viability in human HepG2 cell lines. Programmed cell death was investigated by means of cellular apoptosis assays using Annexin V. The expression of cancer related proteins was detected by Western blotting (WB). Reactive oxygen species (ROS) and calcium were determined by 2,7-dichlorodihydrofluorescein diacetate and Fluo-4, respectively. Intrahepatic HepG2 xenograft mouse model was used to elucidate the effect of tomatine on tumor growth in vivo. Results and Discussion: Tomatine reduced HepG2 cell viability and induced the early apoptosis phase of cell death, consistently with caspase-3, -7, Bcl-2 family, and P53 proteins activation. Furthermore, tomatine increased intracellular ROS and cytosolic Ca+2 levels. Moreover, the NSG mouse xenograft model showed that treating mice with tomatine inhibited HepG2 tumor growth. Conclusion: Tomatine inhibits in vitro and in vivo HCC tumorigenesis in part via modulation of p53, Ca+2, and ROS signalling. Thus, the results suggest the potential cancer therapeutic use of tomatine in HCC patients.

16.
Sci Total Environ ; 842: 156783, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-35724784

RESUMEN

Estuarine saltmarshes from South America are exposed to several anthropogenic impacts due to diverse human activities that occur in both Atlantic/Pacific coastal environments. Primarily, chemical and petrochemical industries negatively impact saltmarshes generating inputs/deposition of non-essential trace elements (NTEs) and polycyclic aromatic hydrocarbons (PAHs) in sediments. The native cordgrass Spartina densiflora inhabits a wide range of environments, from non-impacted to highly impacted areas. It is important to know its performance towards pollution in different environmental settings in South America. The content of Cd, Hg, Pb, and PAHs was determined in the roots and leaves of S. densiflora, bulk sediments (Bs), and rhizosediments (Rs) of estuaries from Argentina, Brazil, and Chile. Differences in NTEs and PAHs levels were observed between Bs, Rs, and Spartina tissues from different saltmarsh areas. Differences in Rs/Bs (RHICF; rhizosediments concentration factors), roots/Bs (RCF; roots concentration factors) and leaves/roots (TF; translocation factors) factors were also found. In terms of NTEs, S. densiflora showed a high capability to increase levels in their Rs (RHICF>1) and bioconcentrate Cd in roots (RCF > 1), while no general translocation (TF < 1) was observed. Conversely, in cordgrass tissues, Bs and Rs, PAHs contents showed RCF and TF > 1, which was in line with lower levels in Rs related to Bs (RHICF<1) in most sites. These findings showed the S. densiflora capacity to retain, remove and/or translocate priority contaminants depending on intrinsic chemical characteristics and the level of contamination. The present study enables future considerations regarding the biomonitoring and phytoremediation/stabilization capabilities of Spartina in coastal environments.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Oligoelementos , Contaminantes Químicos del Agua , Brasil , Cadmio , Monitoreo del Ambiente , Sedimentos Geológicos/química , Humanos , Poaceae , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis
17.
Inquiry ; 59: 469580221086922, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35341376

RESUMEN

PURPOSE: The aim of this research was to investigate the extent to which socioeconomic and regional differences in Brazil may influence the quality of life. To this end, we examined factors associated with health-related quality of life in two populations of oldest-old people, aged 80 and over: one from the Northeast of Brazil and the other from the Southeast. METHODS: 417 participants aged 80 and over were interviewed face-to-face, 179 from Brejo dos Santos, one of the poorest regions in the Northeast; and 238 from São Paulo, one of the largest urban metropolises in Southeast Brazil. Data, which included socioeconomic and demographic factors, health status, and health-related quality of life, were collected using a structured questionnaire. The dependent variable was determined by the completion rate of the 12-item Short Form Survey and analyzed using multiple logistic regression. RESULTS: Although the population of São Paulo had four times as many long-lived women than men, had better literacy levels, used more medications, and presented a greater prevalence of symptoms suggestive of depression in comparison to the Northeast's population, no difference was observed in the proportion of good physical components among the two populations, 54.3% in Brejo dos Santos' oldest-old and 50.4% in São Paulo's (P = .6272). Quality and quantity of sleep were factors that most affected the health-related quality of life among the oldest-old of Northeast. CONCLUSION: Factors associated with health-related quality of life were different among the oldest-old people of the two locations, thereby corroborating the heterogeneous nature of the longevous population.


Asunto(s)
Calidad de Vida , Sueño , Anciano de 80 o más Años , Brasil/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
18.
J Trace Elem Med Biol ; 71: 126928, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35032836

RESUMEN

BACKGROUND: Thimerosal (TM) is an organic mercury compound used as a preservative in many pharmacological inputs. Mercury toxicity is related to structural and functional changes in macromolecules such as hemoglobin (Hb) in erythrocytes (Ery). METHOD: Human Hb and Ery were used to evaluate O2 uptake based on the TM concentration, incubation time, and temperature. The influence of TM on the sulfhydryl content, production of reactive oxygen species (ROS), and membrane fragility was also evaluated. Raman spectra and atomic force microscopy (AFM) profiles for Ery in the presence and absence of TM were calculated, and docking studies were performed. RESULTS: At 37 °C, with 2.50 µM TM (higher concentration) and after 5 min of incubation in Hb and Ery, we observed a reduction in O2 uptake of up to 50 %, while HgCl2, which was used as a positive control, showed a reduction of at least 62 %. Total thiol assays in the presence of NEM (thiol blocker) quantified the preservation of almost 60 % of free SH in Ery. Based on the Raman spectrum profile from Ery-TM, structural differences in the porphyrinic ring and the membrane lipid content were confirmed. Finally, studies using AFM showed changes in the morphology and biomechanical properties of Ery. Theoretical studies confirmed these experimental results and showed that the cysteine (Cys) residues present in Hb are involved in the binding of TM. CONCLUSION: Our results show that TM binds to human Hb via free Cys residues, causing conformation changes and leading to harmful effects associated with O2 transport.


Asunto(s)
Compuestos de Mercurio , Mercurio , Humanos , Timerosal/farmacología , Timerosal/metabolismo , Eritrocitos/metabolismo , Cisteína , Hemoglobinas , Compuestos de Sulfhidrilo/metabolismo
19.
Aging Clin Exp Res ; 34(3): 619-624, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34460081

RESUMEN

BACKGROUND: Hospitalization episodes in older people are considered critical events because they act in a complex interaction among immobilization effects. AIM: The purpose of this study was to evaluate the effects of hospitalization on older adults' handgrip strength (HGS) and to identify factors related to its performance on the test. METHODS: A cohort study was conducted in a hospital in Natal, Brazil, and enrolled all patients aged 60 years and older between January 2014, and April 2015. Cognitive (Leganés Cognitive Test) and functional status (Katz Index, Lawton Scale and Functional limitation Nagi), physical performance (HGS and gait speed) and depressive symptom assessment (GDS-15) were evaluated at admission and discharge time, as well as information about health and functional status prior to hospitalization. Linear Mixed Models were used to create a predictive model for handgrip strength. RESULTS: A total of 1168 hospitalized older adults were evaluated. A significant decrease in HGS means was observed between admission and discharge time for men (28.12 ± 10.35 and 20.22 ± 14.08 Kgf, p < 0.01) and for women (19.18 ± 7.87 and 14.88 ± 9.79 Kgf, p < 0.01). Undergoing surgery and basal values of the Katz Index were associated with worse HGS performance at discharge. CONCLUSION: A significant decline in handgrip strength during the hospitalization period was observed, which was more pronounced in men. Performing surgery during hospitalization was an important factor for HGS decline in men and women. This study reinforces the importance of early mobilization and muscle strength loss prevention protocols in hospitalized older patients.


Asunto(s)
Fuerza de la Mano , Hospitalización , Anciano , Estudios de Cohortes , Femenino , Fuerza de la Mano/fisiología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Alta del Paciente
20.
Rev. argent. cardiol ; 90(6): 444-452, 2022. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1529549

RESUMEN

RESUMEN Para que una alteración física sea considerada una enfermedad, debe cumplir con los criterios definidos por la OMS. El miocardio no compacto (MNC) es una hipertrabeculación ventricular no bien definida, de la que se duda si es una miocardiopatía en sí misma, o solo una variación de la normalidad. Nosotros analizamos 161 resonancias magnéticas cardíacas realizadas a 140 pacientes con MNC y sus relaciones con otras patologías, exponiéndolos a los criterios de "enfermedad" definidos por la OMS. Tras un análisis crítico, consideramos que no debería ser considerada una miocardiopatía en sí misma, sino una adaptación miocárdica ante condiciones adversas.


ABSTRACT For a physical alteration to be considered a disease, it must meet the criteria defined by the WHO. Non-compact myocardium (NCM) is a non-well-defined ventricular hypertrabeculation, where there are doubts whether it is a cardiomyopathy itself or just a variation of normality. We analyzed 161 studies in 140 patients with NCM and their relationships with other pathologies, exposing them to the "disease" criteria defined by the WHO. After a critical analysis, we consider that it should not be considered a cardiomyopathy in itself, but rather a myocardial adaptation to adverse conditions.

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