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1.
EFSA J ; 22(10): e9033, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39385970

RESUMO

The food enzyme endo-1,3(4)-ß-glucanase (3-(1-3;1-4)-ß-d-glucan 3(4)-glucanohydrolase; EC 3.2.1.6) is produced with the non-genetically modified Talaromyces versatilis strain PF8 by Erbslöh Geisenheim AG. The food enzyme was free from viable cells of the production organism. It is intended to be used in four food manufacturing processes. Dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.110 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 2229 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure resulted in a margin of exposure of at least 20,264. A search for homology of the amino acid sequence of the food enzyme to known allergens was made and four matches with respiratory or contact allergens were found. The Panel considered that the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

2.
EFSA J ; 22(10): e9035, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39391757

RESUMO

The food enzyme triacylglycerol lipase (triacylglycerol acylhydrolase; EC 3.1.1.3) is produced with the non-genetically modified Aspergillus tubingensis strain NL151 by Shin Nihon Chemical Co., Ltd. The food enzyme was free from viable cells of the production organism. It is intended to be used in six food manufacturing processes. Dietary exposure was estimated to be up to 0.278 mg total organic solids (TOS)/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1669 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 6004. A search for homology of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that, the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

3.
EFSA J ; 22(10): e9040, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39376691

RESUMO

The food enzyme ß-glucosidase (ß-d-glucoside glucohydrolase, EC 3.2.1.21) is produced with the non-genetically modified Penicillium guanacastense strain AE-GLY by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in four food manufacturing processes. Subsequently, the applicant has requested to extend its use to include three additional processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of seven food manufacturing processes. The dietary exposure was calculated to be up to 0.206 mg total organic solids (TOS)/kg body weight (bw) per day in European populations. Using the no observed adverse effect level reported in the previous opinion (943 mg TOS/kg bw per day), the Panel derived a margin of exposure of at least 4578. Based on the previous evaluation, the assessment of the new data and the revised margin of exposure, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

4.
J Am Heart Assoc ; 13(20): e036626, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39392134

RESUMO

BACKGROUND: Heart failure (HF) presents a massive burden to health care with a complex pathophysiology that results in HF with reduced left ventricle ejection fraction (EF) or HF with preserved EF. It has been shown that relatively modest changes in protein glycosylation, an essential posttranslational modification, are associated with clinical presentations of HF. We and others previously showed that such aberrant protein glycosylation in animal models can lead to HF. METHODS AND RESULTS: We develop and characterize a novel, tamoxifen-inducible, cardiomyocyte Mgat1 knockout mouse strain, achieved through deletion of Mgat1, alpha-1,3-mannosyl-glycoproten 2-beta-N-acetlyglucosaminyltransferase, which encodes N-acetylglucosaminyltransferase I. We investigate the role of hybrid/complex N-glycosylation in adult HFrEF pathogenesis at the ion channel, cardiomyocyte, tissue, and gross cardiac level. The data demonstrate successful reduction of N-acetylglucosaminyltransferase I activity and confirm that hybrid/complex N-glycans modulate gating of cardiomyocyte voltage-gated calcium channels. A longitudinal study shows that the tamoxifen-inducible, cardiomyocyte Mgat1 knockout mice present with significantly reduced systolic function by 28 days post induction that progresses into HFrEF by 8 weeks post induction, without significant ventricular dilation or hypertrophy. Further, there was minimal, if any, physiologic or pathophysiologic cardiomyocyte electromechanical remodeling or fibrosis observed before (10-21 days post induction) or after (90-130 days post induction) HFrEF development. CONCLUSIONS: The tamoxifen-inducible, cardiomyocyte Mgat1 knockout mouse strain created and characterized here provides a model to describe novel mechanisms and causes responsible for HFrEF onset in the adult, likely occurring primarily through tissue-level reductions in electromechanical activity in the absence of (or at least before) cardiomyocyte remodeling and fibrosis.


Assuntos
Modelos Animais de Doenças , Insuficiência Cardíaca , Camundongos Knockout , Miócitos Cardíacos , N-Acetilglucosaminiltransferases , Volume Sistólico , Animais , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/genética , Volume Sistólico/fisiologia , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Glicosilação , Remodelação Ventricular/fisiologia , Função Ventricular Esquerda , Camundongos , Masculino , Fibrose
5.
J Anal Psychol ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39403971

RESUMO

The realization of the Self, although the absolute basis of Jungian psychology, has internal inconsistencies, is difficult to understand, and offers a promise of realization that cannot be fulfilled. This has weakened it, and its existence is now one of speculation. If this is the case, what is to be done with it in the consulting room? How should it be introduced and accounted for, if at all? This paper suggests some alternatives but concludes that the myth of the Self has gravitas in other established traditions, and it is those that offer a more coherent framework for the emergence of the Self.


La réalisation du Soi, bien qu'elle soit la base absolue de la psychologie jungienne, présente des incohérences internes, est difficile à comprendre et offre une promesse de réalisation qui ne peut être atteinte. Tout cela a conduit à un affaiblissement, et l'existence du Soi est aujourd'hui une spéculation. S'il en est ainsi, qu'en fait­on dans la salle de consultation? Est­ce pertinent d'en faire cas? Comment devrait­il être introduit et pris en compte? Cet article suggère quelques alternatives, mais conclut que le mythe du Soi a de la valeur dans d'autres traditions établies, et que ce sont ces autres traditions qui, elles, offrent un cadre plus cohérent pour l'émergence du Soi.


La realización del Self, aunque es la base absoluta de la psicología Junguiana, tiene inconsistencias internas, es difícil de entender y ofrece una promesa de realización que no puede cumplirse. Esto la ha debilitado, y su existencia es ahora una especulación. Si esto es así, ¿qué hay que hacer con ella en la consulta? ¿Cómo debe introducirse y ser tenida en cuenta? En este artículo se sugieren algunas alternativas, pero se concluye que el mito del Self tiene un lugar de importancia en otras tradiciones establecidas, y son éstas las que ofrecen un marco más coherente para la emergencia del Self.

6.
Int J Mol Sci ; 25(19)2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39408645

RESUMO

Atherosclerosis, characterized by the accumulation of lipoproteins and lipids within the vascular wall, underlies a heart attack, stroke, and peripheral artery disease. Endothelial inflammation is the primary component driving atherosclerosis, promoting leukocyte adhesion molecule expression (e.g., E-selectin), inducing chemokine secretion, reducing the production of nitric oxide (NO), and enhancing the thrombogenic potential. While current therapies, such as statins, colchicine, anti-IL1ß, and sodium-glucose cotransporter 2 (SGLT2) inhibitors, target systemic inflammation, none of them addresses endothelial cell (EC) inflammation, a critical contributor to disease progression. Targeting endothelial inflammation is clinically significant because it can mitigate the root cause of atherosclerosis, potentially preventing disease progression, while reducing the side effects associated with broader anti-inflammatory treatments. Recent studies highlight the potential of the APOA1 binding protein (AIBP) to reduce systemic inflammation in mice. Furthermore, its mechanism of action also guides the design of a potential targeted therapy against a particular inflammatory signaling pathway. This review discusses the unique advantages of repressing vascular inflammation or enhancing vascular quiescence and the associated benefits of reducing thrombosis. This approach offers a promising avenue for more effective and targeted interventions to improve patient outcomes.


Assuntos
Aterosclerose , Inflamação , Humanos , Animais , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Aterosclerose/patologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos
7.
Pathogens ; 13(9)2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39338973

RESUMO

Historical seroprevalence data for Anisakis in Spain vary greatly depending on the sampling region owing to different fish consumption habits. As a result of European Regulation (EC) No. 853/2004, the Royal Decree 1420/2006 on the prevention of parasitosis by Anisakis in fishery products supplied by establishments that serve food to final consumers or to communities came into force in Spain. In this study, a prevalence study of Anisakis in Madrid has been conducted to verify the prophylactic effects of the application of the law. Sera from 500 blood donors from the Fundación Jiménez Díaz University Hospital (Madrid/2021-2023) were collected, and the levels of anti-Anisakis IgG, IgA, and IgE were analyzed by ELISA, comparing them with those obtained with 110 donors from the Red Cross and the "Gómez Ulla" Central Defense Hospital (Madrid/2001-2002). The percentages of positivity in the 2021-2023 donor group were IgG (13.6%), IgA (13.6%), and IgE (2.2%), while in the 2001-2002 donors they were positive for IgG (15.45%), IgA (14.54%), and IgE (11.65%). A reduction of more than 80% was observed in the prevalence of anti-Anisakis IgE in the healthy population of Madrid, which confirmed the positive effect of RD1420/2006, which was later incorporated into RD1021/2022.

8.
Quant Imaging Med Surg ; 14(9): 6285-6293, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39281172

RESUMO

Background: In recent years, several functional imaging studies have shown that the hypothalamus is closely associated with migraine and have suggested that the hypothalamus may be a potential site of migraine generation. Studying the characteristics of the functional network of the hypothalamus in persons with migraines may help to understand the neural mechanisms of migraine. We thus used resting-state functional magnetic resonance imaging (rsfMRI) and Granger causal analysis to investigate the effective connectivity (EC) of the hypothalamus in persons with migraines. Methods: The study included 17 healthy volunteers and 39 persons with migraines. The EC calculation was based on rsfMRI data from a 3-T magnetic resonance imaging scanner. The brain networks of the hypothalamus were compared using a general linear model to determine if there were any differences between the two groups. We used Pearson correlation analysis to examine the correlation between EC values in abnormal brain regions and clinical variables. Results: Compared with healthy controls, those with migraines showed decreased EC from the hypothalamus to the left fusiform and increased EC from the hypothalamus to the medial frontal gyrus/orbital part, right lingual gyrus, left superior frontal gyrus, and right middle frontal gyrus (P<0.05). Meanwhile, persons with migraines also showed decreased EC from the left middle frontal gyrus and right medial frontal gyrus/orbital part to the hypothalamus (P<0.05). EC from the hypothalamus to the left superior frontal gyrus correlated significantly and positively with the visual analogue scale in those with migraines (r=-0.3820; P=0.0164). Conclusions: Disturbances in the EC between the hypothalamus and the prefrontal gyrus and visual cortex may play a key role in the neuropathological features of persons with migraines. The current study adds to our understanding of the complexity of migraine mechanisms.

9.
J Environ Manage ; 370: 122600, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39316881

RESUMO

The presence of fluoride in drinking water can cause various diseases, such as dental fluorosis and skeletal fluorosis. The present study aims to intensify the fluoride removal using a rotating anode electro-coagulation (EC) reactor with providing the proper hydrodynamics conditions. This fluoride removal is modeled and optimized using Response Surface Methodology (RSM) and central composite design (CCD) with varying operational parameters (rotation speed: 20-80 RPM, current: 0.2-1.0 A, initial fluoride concentration: 8-40 mg/L and time: 15-75 min). The maximum fluoride removal is obtained as 96.87% (predicted) and 95.40% (experimental) for the optimized process parameters, initial concentration of 32 mg/L, 0.8 A current, 60 min, and 60 RPM of rotating speed. Kinetic analysis reveals that the removal process adheres to a second-order kinetic model, suggesting that the rate of fluoride removal is dependent on the concentration of fluoride ions present. Isothermal studies indicate that the effective sorption of fluoride onto the generated flocs follows a sips isotherm. The optimal cost analysis is carried out to determine the operational cost as 0.256 USD/m3 for F removal of 93.49% at initial concentration 24 mg/L, time 50 min, current 0.7 A, and rotation 70 rpm and presenting a cost-effective solution for fluoride mitigation. Further, characterizations of the resultant sludge through X-Ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), and the Toxicity Characteristic Leaching Procedure (TCLP) confirmed the safe disposal potential of the sludge. The findings show a promising approach for fluoride removal, combining high efficiency, economic viability, and environmental safety.

10.
Anal Chim Acta ; 1325: 343095, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39244301

RESUMO

BACKGROUND: The availability of new surface enhanced Raman scattering (SERS) substrates is essential to develop quantitative analytical methods. Electrochemistry is an easy, fast and reproducible methodology to prepare SERS substrates on screen-printed electrodes (SPEs). RESULTS: This work proposes new SPEs based on a three-electrode system all made of silver. Using the same ink for the whole electrode system facilitates the fabrication process, reduces production costs, and leads to excellent analytical performance. The results showed that Raman enhancement depends strongly on the type of silver ink. To demonstrate the capabilities of the new electrodes developed, 4-aminosalicylic acid was determined in complex matrices and in the presence of strong interfering compounds such as salicylic acid and acetylsalicylic acid. The proposed analytical method is based on the electrochemical surface oxidation enhanced Raman scattering (EC-SOERS) strategy. AgCl nanocrystals are generated on the working electrode surface, which amplify the Raman signal of 4-aminosalicylic acid. Good figures of merit were obtained both in the absence and in the presence of the interfering compounds, achieving a correct estimation of a 4-aminosalicylic test sample in complex matrices. SIGNIFICANCE: The new SPEs have been demonstrated to be very sensitive and reproducible which, together to the high specificity of the Raman signal, makes this methodology very attractive for chemical analysis.

11.
MethodsX ; 13: 102890, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39233751

RESUMO

The decision-making process consists of finding the best solution to an analyzed problem. This search is carried out in the face of countless interactions when analyzing an alternative criterion by criterion, under which weights are assigned that distinguish the degree of importance they have for the decision-makers. The definition of weight for each criterion gives rise to three lines of thought on the subject. There are objective, subjective, and hybrid methods. This discussion concerns the degree to which experts define the criteria weights. Based on this discussion, we developed a hybrid method to integrate the Entropy and CRITIC methods with the PROMETHEE method, called EC-PROMETHEE. The innovation of this method is that the combination of the Entropy and CRITIC methods does not result in a single set of weights. In reality, the weights generated by each method are used to define each criterion's upper and lower limits. The range of weights generated for each criterion is emulated "n" times and builds a set of weights that are applied to the ranking definition process. The model generates "n" rankings, defining a single ranking. In this article, we demonstrate a step-by-step application of a tool developed in Python called EC-PROMETHEE and use it as an example of the problem of choosing rotary-wing airplanes for application in the military police service.➢The method reduces discretion in determining the weights of the criteria;➢The innovation lies in the use of a range of weights for criteria;➢Consistency in defining the final ranking.

12.
medRxiv ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39228739

RESUMO

Enteric pathogens are a leading causes of diarrheal deaths in low- and middle-income countries. The Exposure Assessment of Campylobacter Infections in Rural Ethiopia (EXCAM) project, aims to identify potential sources of bacteria in the genus Campylobacter and, more generally, fecal contamination of infants during the first 1.5 years of life using Escherichia coli as indicator. A total of 1,310 samples (i.e., hand rinses from the infant, sibling and mother, drinking and bathing water, food and fomite provided to or touched by the infants, areola swabs, breast milk and soil) were collected from 76 households between May 2021 and June 2022. Samples were assigned to two groups by infant age: TP1 (time point 1), infants between 4 and 8 months of age, and TP2, infants between 11 and 15 months of age. Fluorometric and semi-selective colorimetric approaches were used to quantify E. coli in the field samples. Overall, E. coli was ubiquitous within selected households (56.8% across the study). E. coli was more frequently detected than average (>53%) with high concentration (>2-log CFU) in soil (g) and per pair of hand, while the opposite trend (<33%; <1.5-log CFU) was observed in food provided to the infants (g or ml), per areola, and breast milk (ml; P<0.01). E. coli was frequently detected in fomites touched by the infants, drinking and bathing water (>51%), but at low concentration (<1.5-log CFU). Correlation analysis between E. coli concentration in different sample types suggested that the mother's hands might play a key role in the transmission of E. coli between the environment (i.e., soil, bathing water and fomites) and other family members (i.e., infant and sibling; P<0.04; r2>0.3). Using E. coli as surrogate, our study identified mother (hands and areola) as reservoirs likely to be involved in frequent transmission of fecal contaminants to infants within rural Ethiopian households.

13.
Cureus ; 16(8): e66250, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39238766

RESUMO

Lynch syndrome (LS) results from pathogenic variants in mismatch repair genes and is the most common hereditary cancer syndrome. Some guidelines or studies recommend restricting screening according to endometrial cancer (EC) using endometrial biopsy. The pooled sensitivity and specificity of endometrial cytology for detecting endometrial atypical hyperplasia or cancer have been reported to be as high as the pooled sensitivity and specificity of endometrial biopsy. We conduct transvaginal ultrasound and endometrial cytology in women with LS every six months as surveillance for gynecological malignancy. Through this surveillance program, we can detect early-stage EC in women with LS. Here, we report the case of a patient with stage IA EC detected by endometrial cytology and treated completely. The patient was a 47-year-old woman under surveillance for gynecological malignancy. She was diagnosed as having LS with a germline pathogenic variant in MSH6 after surgery for rectal cancer. Thereafter, gynecological surveillance was started. She had regular menstruation and never experienced atypical genital bleeding. However, her cytopathological findings indicated grade 1 endometrial carcinoma. Endometrial biopsy was performed and endometrial carcinoma was confirmed pathologically. A laparoscopic modified radical hysterectomy with bilateral salpingo-oophorectomy was performed. The resected specimen was reviewed pathologically, and the tumor was finally diagnosed as grade 1 endometrioid carcinoma confined to the endometrium without lymphovascular space invasion. She has remained asymptomatic and free of cancer for five years without any adjuvant therapy. We achieved successful surveillance using endometrial cytology. Endometrial cytology could replace endometrial biopsy as a screening tool for EC.

14.
Int J Environ Health Res ; : 1-20, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39254320

RESUMO

Four hundred and sixty-six references with 625 data reports were included in our study. The high frequency of ratio OC/EC for PM0.1 was observed in 3.92-5.93; PM1 in 1.08-3.08; PM2.5, 2.08-4.08; PM10 in 2.70-4.70 and TSP in 2.66-4.66. The rank order of areas based on the pooled concentration of OC bound to PM2.5 was traffic (17.893 µg/m3) > industrial (10.58 µg/m3) > urban (7.696 µg/m3) > rural (4.08 µg/m3). The rank order of areas based on the pooled (mean) concentration of EC in PM2.5 was traffic (17.893 µg/m3) > industrial (2.65 µg/m3) > Urban (1.48 µg/m3) > rural (1.06 µg/m3). The pooled concentrations of OC and EC bound to PM2.5 in traffic areas were higher than in other areas. Therefore, it is recommended that monitoring and effectively reducing concentration plans are carried out, especially in traffic areas.

15.
ACS Appl Mater Interfaces ; 16(36): 47406-47415, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39222040

RESUMO

Lithium is a promising anode material for advanced batteries because of its high capacity and low redox potential. However, its practical use is hindered by nonuniform Li deposition and dendrite formation, leading to safety concerns in Li metal batteries. Our study shows that Ag-based materials enhance the uniformity of Li deposition on Ag-modified Li (AgLi) surfaces, thereby addressing these key challenges. This improvement is due to the strong affinity of Ag for Li, which promotes uniform deposition and dissolution. Additionally, the AgLi surface demonstrated an improved cycling stability, which is crucial for long-term battery reliability. Emphasizing our analytical approach, we utilized comprehensive techniques such as Kelvin probe force microscopy (KPFM) and electrochemical atomic force microscopy (EC-AFM) to locally analyze the electrical properties and unravel the Li deposition/dissolution mechanisms. KPFM analysis provided crucial insights into surface potential variations, while EC-AFM highlighted topographical changes during the Li deposition and dissolution processes, contributing significantly to the development of safer and more efficient Li metal batteries.

16.
Mol Med Rep ; 30(5)2024 11.
Artigo em Inglês | MEDLINE | ID: mdl-39239742

RESUMO

The tetraspanin family of membrane proteins is essential for controlling different biological processes such as cell migration, penetration, adhesion, growth, apoptosis, angiogenesis and metastasis. The present review summarized the current knowledge regarding the expression and roles of tetraspanins in different types of cancer of the digestive system, including gastric, liver, colorectal, pancreatic, esophageal and oral cancer. Depending on the type and context of cancer, tetraspanins can act as either tumor promoters or suppressors. In the present review, the importance of tetraspanins in serving as biomarkers and targets for different types of digestive system­related cancer was emphasized. Additionally, the molecular mechanisms underlying the involvement of tetraspanins in cancer progression and metastasis were explored. Furthermore, the current challenges are addressed and future research directions for advancing investigations related to tetraspanins in the context of digestive system malignancies are proposed.


Assuntos
Neoplasias do Sistema Digestório , Tetraspaninas , Humanos , Tetraspaninas/metabolismo , Tetraspaninas/genética , Neoplasias do Sistema Digestório/metabolismo , Neoplasias do Sistema Digestório/genética , Neoplasias do Sistema Digestório/patologia , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Animais
17.
Bull Environ Contam Toxicol ; 113(3): 37, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225823

RESUMO

Ecuador's wetlands and aquatic ecosystems are chronically exposed to ash contamination due to the frequent volcanoes' eruptions in the country. Still, the short and long-term effects of ash contamination on the aquatic biota are not well understood. We used ashes released by the Cotopaxi volcano in 2016 to investigate their acute and chronic effects in Daphna magna. We calculated the half maximal effective concentration (EC50) after 2 and 21 days of exposure, the non-observed effect concentration (NOEC), and the lowest observed effect concentration (LOEC) on offspring production. We also analyzed the metal concentration present in the ashes. The EC50 values at 2 and 21 days were found at 80% and 5% ash leachate concentrations, respectively. After 21 days of exposure, high mortality and low neonatal production were observed in all leachate concentrations (NOEC was at 15%, and LOEC was at 20% leachate concentration). Our results suggest that the ashes from the Cotopaxi volcano can cause acute and chronic toxicity to aquatic life and should be classified as hazardous waste, depending on the dose. There is an urgent need for further studies that assess toxicity caused by the intense volcanic activity in Ecuador.


Assuntos
Daphnia , Erupções Vulcânicas , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Equador , Daphnia/efeitos dos fármacos , Testes de Toxicidade Crônica , Testes de Toxicidade Aguda , Monitoramento Ambiental , Daphnia magna
18.
Artigo em Inglês | MEDLINE | ID: mdl-39302711

RESUMO

Electric pacing of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) has been increasingly used to simulate cardiac arrhythmias in vitro and to enhance cardiomyocyte maturity. However, the impact of electric pacing on cellular electrophysiology and Ca2+-handling in differentiated hiPSC-CM is less characterized. Here we studied the effects of electric pacing for 24h or 7d at a physiological rate of 60 bpm on cellular electrophysiology and Ca2+-cycling in late-stage, differentiated hiPSC-CM (>90% troponin+, >60d post differentiation). Electric culture pacing for 7d did not influence cardiomyocyte cell size, apoptosis or generation of reactive oxygen species in differentiated hiPSC-CM compared to 24h pacing. However, epifluorescence measurements revealed that electric pacing for 7d improved systolic Ca2+-transient amplitude and Ca2+-transient upstroke, which could be explained by elevated sarcoplasmic reticulum Ca2+-load and SERCA activity. Diastolic Ca2+-leak was not changed in line-scanning confocal microscopy suggesting that the improvement in systolic Ca2+-release was not associated with a higher open probability of RyR2 during diastole. While bulk cytosolic Na+-concentration and NCX activity were not changed, patch-clamp studies revealed that chronic pacing caused a slight abbreviation of the action potential duration (APD) in hiPSC-CM. We found in whole-cell voltage-clamp measurements that chronic pacing for 7d led to a decrease in late Na+-current, which might explain the changes in APD. In conclusion, our results show that chronic pacing improves systolic Ca2+-handling and modulates the electrophysiology of late-stage, differentiated iPSC-CM. This study might help to understand the effects of electric pacing and its numerous applications in stem cell research including arrhythmia simulation.

19.
Water Environ Res ; 96(9): e11128, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39267330

RESUMO

Microalgae are unicellular, photosynthetic organisms in aquatic environments and are sensitive to water quality and contaminants. While green algae and diatoms are widely used for toxicity assessments, there is a relatively limited amount of toxicity data available for freshwater dinoflagellates. Here, we evaluated the sub-lethal effects of the metals Cu, Cr, Ni, and Zn and the herbicides atrazine and S-metolachlor on the freshwater dinoflagellate Palatinus apiculatus. Based on the 72-h median effective concentration (EC50), P. apiculatus showed sensitive responses to metals in the order of Cu (0.052 mg L-1), Cr (0.085 mg L-1), Zn (0.098 mg L-1), and Ni (0.13 mg L-1). Among the tested herbicides, P. apiculatus was more sensitive to atrazine (0.0048 mg L-1) than S-metolachlor (0.062 mg L-1). In addition, we observed morphological alterations and significant increases in reactive oxygen species (ROS) production in cells exposed to 0.05 mg L-1 of Cu and 0.005 mg L-1 of atrazine. These indicated that metals and pesticides induced oxidative stress in cellular metabolic processes and consequently caused severe physiological damage to the cells. Our results provide baseline data on the toxic effects of typical environmental contaminants on freshwater dinoflagellate, suggesting that P. apiculatus could be used as a bioindicator in freshwater toxicity assessments. PRACTITIONER POINTS: The sub-lethal effects of metals and pesticides on the freshwater dinoflagellate Palatinus apiculatus were evaluated. Palatinus sensitively responded to metals and pesticides; of test chemicals, atrazine (0.0048 mg L-1 of EC50) was the most sensitive. Metals and pesticides induced oxidative stress and consequently caused severe physiological damage to the Palatinus cells. The freshwater dinoflagellate Palatinus can be used as a bioindicator in freshwater toxicity assessments.


Assuntos
Dinoflagellida , Poluentes Químicos da Água , Dinoflagellida/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Água Doce , Metais/toxicidade , Praguicidas/toxicidade , Herbicidas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Atrazina/toxicidade
20.
J Biopharm Stat ; : 1-12, 2024 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-39306756

RESUMO

Bioassays are regulated, analytical methods used to ensure proper activity (potency) of biological products at release and during long-term storage. Potency is commonly reported on a relative basis by comparing and calibrating a concentration-response curve from the test material to that of a reference standard material. The relative potency approach depends on an assumption that the two concentration-response curves exhibit similar (equivalent) shapes, except for a potency shift. In certain circumstances, however, biological factors preclude the similarity assumption, and the traditional approach becomes unworkable. The antibody-mediated cytotoxicity assay is one example where the similarity assumption does not always hold. Other examples also arise in the fields of toxicology and pharmacology. In this work, we present a non-constant mean relative potency approach which averages the relative potency across a common range of the concentration-response curves. The proposed method captures the changing nature of the relative potency into a summary statistic that can be reported for batch calibration and quality control purposes. We provide inferential methods for this statistic and summarize the results of a simulation comparing these methods across a number of non-constant relative potency scenarios and assay conditions.

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