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It has long been thought that exocytosis was driven exclusively by well-studied fusion proteins. Some decades ago, the role of lipids became evident and escalated interest in the field. Our laboratory chose a particular cell to face this issue: the human sperm. What makes this cell special? Sperm, as terminal cells, are characterized by their scarcity of organelles and the complete absence of transcriptional and translational activities. They are specialized for a singular membrane fusion occurrence: the exocytosis of the acrosome. This unique trait makes them invaluable for the study of exocytosis in isolation. We will discuss the lipids' role in human sperm acrosome exocytosis from various perspectives, with a primary emphasis on our contributions to the field. Sperm cells have a unique lipid composition, very rare and not observed in many cell types, comprising a high content of plasmalogens, long-chain, and very-long-chain polyunsaturated fatty acids that are particular constituents of some sphingolipids. This review endeavors to unravel the impact of membrane lipid composition on the proper functioning of the exocytic pathway in human sperm and how this lipid dynamic influences its fertilizing capability. Evidence from our and other laboratories allowed unveiling the role and importance of multiple lipids that drive exocytosis. This review highlights the role of cholesterol, diacylglycerol, and particular phospholipids like phosphatidic acid, phosphatidylinositol 4,5-bisphosphate, and sphingolipids in driving sperm acrosome exocytosis. Furthermore, we provide a comprehensive overview of the factors and enzymes that regulate lipid turnover during the exocytic course. A more thorough grasp of the role played by lipids transferred from sperm can provide insights into certain causes of male infertility. It may lead to enhancements in diagnosing infertility and techniques like assisted reproductive technology (ART).
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This work proposes a novel method to determine the Cd(II) and Cr(III) content in commercial sugar samples. It is based on the extraction of the analytes (as ammonium pyrrolidine dithiocarbamate complexes) into a semipermeable membrane device (SPMD) filled with CHCl3. After extraction, the SPMD was deployed and opened, and the analytes were recovered from the organic phase by back extraction with a 4.2 mol L-1 HNO3 solution. The analytes present in the acid extract were measured with graphite furnace atomic absorption spectrometry. Under optimized conditions, the limit of quantification of the method was 1.2 and 3.1 ng g-1 for Cd(II) and Cr(III), respectively. Twelve samples of different types of sugar were analyzed. In addition, a recovery test was performed to evaluate the accuracy of the method. The recovery percentage was 90 %-102 % for Cd(II) and 85.2 %-103 % for Cr(III).
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Trypanosomes are protozoan parasites responsible for human diseases such as Chagas disease, African trypanosomiasis, and leishmaniasis. These organisms' growth in various environments and exhibit multiple morphological stages, while adapting their surface components. They acquire and release materials extensively to get nutrients and manage interactions with the extracellular environment. They acquire and utilize proteins, lipids, and carbohydrates for growth via using membrane transport and endocytosis. Endocytosis takes place through distinct membrane areas known as the flagellar pocket and cytostome, depending on the parasite species and its developmental stage. Some forms establish a complex endocytic system to either store or break down the absorbed materials. In contrast, membrane transport facilitates the uptake of small molecules like amino acids, carbohydrates, and iron via particular receptors on the plasma membrane. Concurrently, these parasites secrete various molecules such as proteins, enzymes, nucleic acids, and glycoconjugates either in soluble form or enclosed in extracellular vesicles, which significantly contribute to their parasitic behavior. These activities require exocytosis through a secretory pathway in certain membrane domains such as the flagellum, flagellar pocket, and plasma membrane, which are controlled at various developmental stages. The main features of the endocytic and exocytic mechanisms, as well as the organelles involved, are discussed in this chapter along with their connection to the formation of exosomes and extracellular vesicles in the Tritryp species.
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Vesículas Extracelulares , Vesículas Extracelulares/metabolismo , Endocitosis , Animales , Humanos , Trypanosomatina/metabolismoRESUMEN
OBJECTIVES: To clarify the hearing outcomes after endoscopic type I tympanoplasty for medium and large perforations due to chronic otitis media. METHODS: We examined the clinical records of patients who underwent endoscopic type I tympanoplasty for medium and large perforations of the eardrum resulting from chronic otitis media between January 2019 and December 2021. We analyzed the changes in hearing pre- and post-operation in patients with healed eardrums and assessed the impact of tympanosclerosis on hearing. Patients with incomplete follow-up data, middle ear cholesteatoma, stapes fixation, severe lesions in the tympanic antrum and mastoid necessitating mastoidectomy and/or ossicular chain reconstruction were excluded. RESULTS: A total of 156 patients underwent analysis for audiological outcomes. Among them, 63 had medium tympanic membrane perforations, with 18 cases showing calcification of the tympanic membrane and 20 cases with calcification in the tympanic cavity. Additionally, 93 cases had large tympanic membrane perforations, with 25 cases showing tympanic membrane calcification and 32 cases with tympanic cavity calcification. Prior to surgery, the Air Conduction threshold (AC) in the large perforation group was higher than in the medium perforation group, particularly at low frequencies, measuring (47.4 ± 13.3 dB) and (41.2 ± 14.7 dB), respectively (p-value < 0.05). Following surgery, both groups experienced an improvement in AC, measuring (33.6 ± 13.9 dB) and (32.6 ± 12.8 dB), respectively, with no significant difference noted (p-value > 0.05). There was no significant change in Bone Conduction threshold (BC) before and after surgery in either the large or medium perforation groups (all p-values > 0.05). Except for 4000 Hz an increase, bone conduction did not increase post-surgery, instead showing further improved. Pre-surgery, the Air-Bone Gap (ABG) in the large and medium perforation groups was (27.7 ± 8.5 dB) and (21.8 ± 8.3 dB), respectively, mainly affecting low frequencies, with a statistically significant difference noted (p-value < 0.05). Following surgery, ABG in both groups improved to (16.3 ± 7.6 dB) and (15.7 ± 8.4 dB), respectively, with no significant difference observed (p-value > 0.05). There was no significant difference in hearing pre-surgery among the groups with No calcification (No), Tympanic Membrane Calcification (TM), and Tympanic Cavity Calcification (TC). However, TC significantly impacted low frequency (250-500 Hz) AC and ABG. The differences in AC and ABG pre-surgery between TC and No group, and TC and TM group (at 250-500 Hz) were statistically significant (all p-values < 0.05). Preoperative ABG in TM group was better than in No group and TC group, suggesting minimal impact of tympanic membrane calcification on hearing. No interaction was observed between tympanic membrane perforation size and tympanosclerosis on hearing. Post-surgery, both large and medium tympanic membrane perforation groups, regardless of tympanosclerosis presence, showed good AC and ABG, with no statistically significant difference in â³ABG (all p-values > 0.05). CONCLUSION: Preoperative AC and ABG were increase in cases of large tympanic membrane perforations and medium tympanic membrane perforations with tympanic cavity calcification. Surgical intervention led to more significant hearing improvement in these patients. However, irrespective of tympanic membrane perforation size and the presence of tympanosclerosis, as long as the ossicular chain remains intact and functional, postoperative AC and ABG outcomes are satisfactory. Endoscopic type I tympanoplasty proves effective in achieving improved hearing outcomes for patients with medium to large tympanic membrane perforations and tympanosclerosis, provided there is no ossicle chain fixation. LEVEL OF EVIDENCE: Level 4.
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In response to Dr. Kasperkiewicz's commentary on our meta-analysis conducted by Bocanegra-Oyola et al., we fully agree with refining diagnostic processes for ocular pemphigoid, particularly in differentiating it from pseudopemphigoid. We concur that relying solely on clinical findings may result in misdiagnoses. Confirming the diagnosis via biopsy can be challenging, requiring multiple biopsies in some patients, and should always be supported by a multidisciplinary clinical assessment involving ophthalmologists and dermatologists.
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Galectins constitute a family of soluble lectins with unique capacity to induce macroscale rearrangements upon interacting with cell membrane glycoconjugates. Galectin-8 (Gal-8) is acknowledged for its role in facilitating antigen uptake and processing upon engaging with cell surface glycoconjugates on antigen-presenting cells (APCs). Gal-8 consists of two covalently fused N- and C-terminal carbohydrate recognition domains (N- and C-CRD), each exhibiting distinct glycan specificity. In this study, we utilized single N- and C-CRD recombinant proteins to dissect the nature of Gal-8-glycan interactions during antigen internalization enhancement. Single C-CRD was able to replicate the effect of full-length Gal-8 (FLGal-8) on antigen internalization in BMDCs. Antigen uptake enhancement was diminished in the presence of lactose or when N-glycosylation-deficient macrophages served as APCs, underscoring the significance of glycan recognition. Measurement of the elastic modulus using Atomic Force Microscopy unveiled that FLGal-8- and C-CRD-stimulated macrophages exhibited heightened membrane stiffness compared to untreated cells, providing a plausible mechanism for their involvement in endocytosis. C-CRD proved to be as efficient as FLGal-8 in promoting antigen degradation, suggesting its implication in antigen-processing induction. Lastly, C-CRD was able to replicate FLGal-8-induced antigen presentation in the MHC-II context both in vitro and in vivo. Our findings support the notion that Gal-8 binds through its C-CRD to cell surface N-glycans, thereby altering membrane mechanical forces conducive to soluble antigen endocytosis, processing, and presentation to cognate CD4 T-cells. These findings contribute to a deeper comprehension of Gal-8 and its mechanisms of action, paving the way for the development of more efficacious immunotherapies.
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The World Health Organization has emphasized the importance of consuming small fruits for the prevention of chronic health problems, including diabetes, cardiovascular diseases, cancer, and obesity, which are named chronic non-communicable diseases (NCDs). Azara serrata Ruiz & Pav., commonly called "aroma de Castilla", is a shrub endemic to Chile from the Salicaceae family that produces an underutilized blue-grey berry that grows wild in southern Chile. The species is widely used as a medicinal plant by the Andean communities of southern Chile. In this work, a high-resolution mass spectrometric analysis of the methanolic extract revealed several phenolic compounds for the first time in the edible berry of this endemic species. Furthermore, several glycosylated anthocyanins were detected and quantified using UHPLC coupled with UV/Vis detection and trapped ion mobility mass spectrometry (UHPLC-DAD-TIMS-TOF) for the anthocyanin-rich extract, which was prepared using an optimized anthocyanin extraction protocol. The extract proved to be active in the inhibition of several enzymes linked to NCDs, such as acetylcholinesterase, tyrosinase, amylase, lipase, and glucosidase (IC50 = 3.92 ± 0.23, 12.24 ± 0.03, 11.12 ± 0.10, 32.43 ± 0.0, and 371.6 ± 0.0 µg/mL, respectively). Furthermore, the extract concentrated in anthocyanins showed good antioxidant activity evidenced by the bleaching of the radicals DPPH and ABTS, ferric-reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC). The results show that these neglected endemic small berries can be a source of healthy phytochemicals. These Chilean berries can be used as functional food and their extracts are candidates for use as functional ingredients in naturally healthy products.
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The development of new wound dressings made from biomaterials, which offer a better cost-benefit ratio and accelerate the healing process, is increasing nowadays. Various biopolymers can be electrospun to form functional membranes for wound healing. Therefore, in this study, chitosan and nanochitosan membranes with or without hyaluronic acid were prepared using the electrospinning technique, characterized and evaluated in the healing of skin wounds in rats. Chitosan and nanochitosan solutions, with or without hyaluronic acid, were prepared at concentrations of 1%-4% using PEO (polyethylene oxide) and subjected to the electrospinning process to obtain membranes characterized by scanning electron microscopy (SEM), mechanical tests, and antimicrobial activity. The healing effect of the membranes was evaluated by monitoring the area of the lesions, contraction of the wounds, histologic analysis, and induction of pro-inflammatory cytokine (IL-1 α and TNF-α) production in rats. The nanochitosan and nanochitosan membranes with hyaluronic acid achieved greater fiber diameter and uniformity, resistance, elasticity, and thermal stability, in addition to good adhesion to the wound bed and permeation capacity. Despite not presenting antimicrobial activity in vitro, they contributed to the production of pro-inflammatory interleukins in the animals tested, provided physical protection, reduced the wound area more markedly until the seventh day of the evaluation, with an acceleration of the healing process and especially when functionalized with hyaluronic acid. These results indicate that the membranes may be promising for accelerating the healing process of chronic wounds in humans.
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Quitosano , Ácido Hialurónico , Membranas Artificiales , Piel , Cicatrización de Heridas , Quitosano/química , Quitosano/farmacología , Animales , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Cicatrización de Heridas/efectos de los fármacos , Ratas , Piel/lesiones , Piel/metabolismo , Masculino , Ratas Wistar , VendajesRESUMEN
Brazil has a very large biological variety, which is an almost inexhaustible source of substances of pharmacological and biotechnological interest. Several studies have demonstrated the presence of bioactive peptides in insect hemolymph and their potential use as therapeutic agents. However, few data are available regarding molecules extracted from insects with anti-apoptotic action. The objective of this work was to identify the presence of proteins from the hemolymph of caterpillars of the Megalopygidae family with pharmacological and biotechnological interest. This study provides preliminary and innovative information on a new substance that inhibits cellular apoptopsis and stabilizes the tested cells, impacting the cytoskeleton, maintaining cellular structure and its functions. To this, two species of Megalopygidae family were studied, Podalia sp. and Megalopyge albicolis. Cytotoxicity tests on Vero and Sf-9 cells revealed that the hemolymph of both caterpillars was cytotoxic only at concentrations greater than 5%v/v. In the anti-apoptotic activity assays, it was verified that the supplementation of cell cultures with only 1% of hemolymph v/v is sufficient to inhibit cell death by apoptosis induced by different inducers such as terbutyl, actinomycin D, hydrogen peroxide, or even by nutrient depletion. For this study, cells were stained with trypan blue, crystal violet, and fluorescent markers to cytoskeleton (actin and tubulin), mitochondria membrane electric potential (JC-1), and apoptosis marker (acridine orange and ethidium). The protein responsible for anti-apoptotic action was isolated through gel filtration chromatography, using an AKTA purifier high-resolution liquid chromatography system. The hemolymph was fractionated into 3 pools for Podalia sp. and 6 pools for M. abicolis. In the antiapoptotic tests, semi-purified hemolymph from both caterpillars showed anti-apoptotic effect in VERO and SF-9 cells, pre-treated with only 1% v/v of hemolymph and induced to death by different and apoptotic inductors. Was observed that the molecule with anti-apoptotic effect is present in pool 3 in both hemolymphs. This protector effect blocked and attenuated the disruption of the cytoskeleton (actin filaments), being that the protective effect also was observed on the integrity of the mitochondrial membrane of SF-9 cells pre-treated with both hemolymphs and treated with the apoptosis inducer Terbutil at concentrations of 25 to 100 µM. By acting on the mitochondrial pathway of death by apoptosis, and by maintaining the structure of the cytoskeleton and cellular functions, pathway that can cause disorders and diseases neurodegenerative, the substances present in the hemolymph of these and other caterpillars could be good candidates in studies for the treatment of neurodegenerative diseases such as Parkinson's disease and Alzheimer's.
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Background: The diagnosis and treatment of lung, colon, and gastric cancer through the histologic characteristics and genomic biomarkers have not had a strong impact on the mortality rates of the top three global causes of death by cancer. Methods: Twenty-five transcriptomic analyses (10 lung cancer, 10 gastric cancer, and 5 colon cancer datasets) followed our own bioinformatic pipeline based on the utilization of specialized libraries from the R language and DAVID´s gene enrichment analyses to identify a regulatory metafirm network of transcription factors and target genes common in every type of cancer, with experimental evidence that supports its relationship with the unlocking of cell phenotypic plasticity for the acquisition of the hallmarks of cancer during the tumoral process. The network's regulatory functional and signaling pathways might depend on the constant crosstalk with the microbiome network established in the oral-gut-lung axis. Results: The global transcriptomic network analysis highlighted the impact of transcription factors (SOX4, TCF3, TEAD4, ETV4, and FOXM1) that might be related to stem cell programming and cancer progression through the regulation of the expression of genes, such as cancer-cell membrane receptors, that interact with several microorganisms, including human T-cell leukemia virus 1 (HTLV-1), the human papilloma virus (HPV), the Epstein-Barr virus (EBV), and SARS-CoV-2. These interactions can trigger the MAPK, non-canonical WNT, and IFN signaling pathways, which regulate key transcription factor overexpression during the establishment and progression of lung, colon, and gastric cancer, respectively, along with the formation of the microbiome network. Conclusion: The global transcriptomic network analysis highlights the important interaction between key transcription factors in lung, colon, and gastric cancer, which regulates the expression of cancer-cell membrane receptors for the interaction with the microbiome network during the tumorigenic process.
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Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Transcriptoma , Humanos , Neoplasias Pulmonares/microbiología , Neoplasias Pulmonares/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Biología Computacional , Pulmón/microbiología , Pulmón/patología , Boca/microbiología , Transducción de Señal , Microbioma Gastrointestinal/genética , Microbiota/genética , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/genética , Regulación Neoplásica de la Expresión GénicaRESUMEN
Introduction: Maculopathy secondary to pathologic myopia (PM) is increasingly causing visual impairment and blindness worldwide. PM is associated with tractional maculopathy that ranges from macular foveoschisis to macular hole. These disorders are treated with different options that offer variable results, reflecting the need for new techniques that address myopic maculopathy with consistent outcomes. Methods: Since human amniotic membrane (HAM) has been reported to be safe for intraocular use and to promote retinal healing, it was incorporated as an adjuvant in pars plana vitrectomy in patients with different tractional disorders related to myopia. This work presents a prospective, consecutive case series of seven patients with high myopia who underwent a 25-gauge vitrectomy with ILM peeling and HAM transplantation. Results and Discussion: Our six-month results show that this novel technique delivers functional success related to tissue permanence without recurrence of traction that translates into visual acuity gain and maintenance that are superior to other techniques.
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INTRODUCTION: An infrequent yet known complication of ECMO is abdominal compartment syndrome requiring emergency laparotomy. Also, the need for prolonged enteral nutrition while on ECMO may require endoscopic gastrostomy to maintain adequate nutritional status. Here we describe our experience with emergency laparotomy and endoscopic gastrostomy in patients on ECMO support. METHODS: We retrieved patient histories from our clinical archives and performed a retrospective description of all patients taken to an emergency laparotomy or endoscopic gastrostomy while on ECMO support at our cardiovascular referral center from July 2019 through June 2024. RESULTS: During the research period of 5 years a total of 401 patients were placed on ECMO support for either cardiogenic shock or respiratory failure. A total of 27 (7%) patients required an abdominal intervention while on ECMO. 14 (3.5%) patients required emergency laparotomy and 13 (3.2%) of patients required endoscopic gastrostomy tube placement. Overall 30-day mortality of all patients requiring a general surgery procedure while on ECMO support was 33%. CONCLUSION: ECMO support can result in many complications despite its many benefits. Patients who require emergency laparotomy while on ECMO have lower survival-to-discharge and higher mortality at 30 days. Endoscopic gastrostomy however, can be safely performed on ECMO with little to no bleeding complications despite anticoagulation.
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The aim of the present study was to report the remodeling of the basement membrane through physiological stimulus during the treatment of fibrosis in a lower limb with lymphedema. A clinical trial was conducted involving the evaluation of the basement membrane in skin biopsies before and after treatment for clinical stage II lower limb lymphedema using the Godoy method for the reversal of lymphedema and skin fibrosis. The samples were stained with Gomori's reticulin stain and evaluated using Weibel's multipoint morphometric method at the Godoy Clinic. Prior to treatment for lymphedema, rupture and important discontinuity of the basement membrane was found. After treatment, structural continuity and thickness had returned to the regions of previous rupture. The difference was statistically significant (P < 0.05, paired t-test). The present study reports that physiological stimuli targeting the lymphatic system led to the clinical reversal of fibrosis, as well as stimulate the synthesis of extracellular matrix proteins and the reconstruction of the basal lamina of the skin.
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Neosporosis is one of the major causes of abortion in cattle, and it is responsible for significant economic losses in those animals. Thus, this study aimed to evaluate indirect ELISA using subcellular fractions of Neospora caninum obtained via sucrose gradient separation. Eighty-five sera from dairy cattle previously tested using indirect immunofluorescence assay (IFA) were used. Three distinct bands were separated at 1.0 M, 1.4 M, 1.6 M, and the pellet at 1.8 M, which were identified as fractions one (F1), two (F2), three (F3), and four (F4), respectively. These fractions showed parasite membranes in the F1, rhoptry and conoids in the F2, mitochondria in the F3, and tachyzoite ghosts remain in F4. Indirect ELISAs for IgM, and IgG were performed. Additionally, sensitivity, specificity, and kappa values were defined considering the IFA as the gold standard. The highest and lowest specificities were observed for F1 (76 %) and F3 (16 %), respectively. F2 and F4 showed the highest sensitivity (93.3 %), kappa agreement (0.46), and Negative Preventive Value (NPV) (73 %) respectively. It was possible to standardize indirect ELISAs using whole soluble antigen and subcellular fractions of N. caninum, and F2 and F4 showed higher sensitivity (93.3 %), kappa (0.41), and NPV values (75 %) than F1, and F3, which could be used for epidemiology studies such as screening.
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On an industrial scale, the residues accumulated in essential oil distilleries can be compared to the volume of residues produced in the textile industry. Although these residues are discarded, they possess molecules with diverse biological activities, including their application in phytopathogen control. In this study, the chemical profile of the residue from the hydrodistillation of Lantana camara L. leaves was determined using high-performance liquid chromatography (HPLC). Additionally, the effect of the residue on cells was assessed by determining plasma membrane integrity, levels of reactive oxygen species (ROS) production, and mitochondrial potential depolarization. The viability and cell density of Phytomonas serpens parasites significantly decreased after treatment with increasing concentrations of the lyophilized residue from accession LAC-038 (RL038). RL038 reduced cell viability by an average of 61.36%. ROS levels increased by approximately 2 × and 3 × at RL038 concentrations of 120 µg/mL and 180 µg/mL, respectively. It was observed that the same concentrations modified mitochondrial potential, reducing fluorescence by 44.6% and 46.8%, respectively. Analytical liquid chromatography of RL038 revealed the presence of 17 peaks subsequently classified as phenolic acids and flavonoids. RL038 from the hydrodistillation of Lantana camara L. leaves is a source of biologically active compounds with antiprotozoal potential.
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Lantana , Aceites Volátiles , Aceites Volátiles/farmacología , Aceites Volátiles/química , Lantana/química , Destilación , Especies Reactivas de Oxígeno/metabolismo , Liofilización , Cromatografía Líquida de Alta PresiónRESUMEN
This narrative review delves into the intricate interplay between the lungs and the kidneys, with a focus on elucidating the pathogenesis of diseases influenced by immunological factors, acid-base regulation, and blood gas disturbances, as well as assessing the effects of various therapeutic modalities on these interactions. Key disorders, such as anti-glomerular basement membrane (anti-GBM) disease, the syndrome of inappropriate antidiuretic hormone secretion (SIADH), and Anti-neutrophil Cytoplasmic Antibodies (ANCA) associated vasculitis (AAV), are also examined to shed light on their underlying mechanisms. This review also explores the relationship between acute respiratory distress syndrome (ARDS) and acute kidney injury (AKI), emphasizing how inflammatory mediators can lead to systemic damage and impact multiple organs. In ARDS, fluid overload exacerbates pulmonary edema, while imbalances in blood volume, such as hypovolemia or hypervolemia, can precipitate renal dysfunction. The review highlights how mechanical ventilation strategies can compromise renal blood flow, trigger systemic inflammation, and induce hemodynamic and neurohormonal alterations, all contributing to lung and kidney damage. The impact of extracorporeal membrane oxygenation (ECMO) on lung-kidney interactions is evaluated, highlighting its role in severe respiratory failure and its renal implications. Emerging therapies, such as mesenchymal stem cells and extracellular vesicles, are discussed as promising avenues to mitigate organ damage and enhance outcomes in critically ill patients. Overall, this review offers a nuanced exploration of lung-kidney dynamics, bridging historical insights with contemporary perspectives. It underscores the clinical significance of these interactions in critically ill patients and advocates for integrated management approaches to optimize patient outcomes.
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The data presented in this article is generated by a steady-state simulation for performing a techno-economic assessment for comparing three electrolysis technologies in the PtM context. The data is focused on two aspects. First, the description of the steady-state simulation of six PtM systems modeled using Aspen Custom Modeler (ACM) and Aspen Plus (AP). Second, an economic assessment is carried out for each of the mentioned PtM systems to compare the feasibility, the profitability and performance of these systems on a larger scale to produce synthetic natural gas, power generation and carbon utilization given in the main research article. Three electrolysis technologies (namely Alkaline Electrolysis - AE, Proton Exchange Membrane Electrolysis - PEME and Solid Oxide Electrolysis - SOE) were modeled having in mind two methane applications: a combined cycle for power generation and the syngas generation. In addition, on each PtM system is carried out an economic evaluation by calculating fixed capital investment (FCI) and manufacturing costs (MC).
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Preeclampsia (PE) is a prevalent obstetric complication affecting approximately 3-5% of pregnancies worldwide and is a major cause of maternal and perinatal morbidity and mortality. Preeclampsia is considered a disease of the endothelial system that can progress to eclampsia, characterized by seizures. Early diagnosis and appropriate management are crucial to improving maternal and fetal outcomes, as preeclampsia can lead to severe complications such as placental abruption, fetal growth restriction, and stroke. The pathophysiology of PE is complex, involving a combination of genetic, acquired, and immunological factors. A central feature of the condition is inadequate placentation and impaired uteroplacental perfusion, leading to local hypoxia, endothelial dysfunction, vasoconstriction, and immunological dysregulation. Recent evidence suggests that dysregulation of ion transporters may play a significant role in the adaptation of uterine circulation during placentation. These transporters are essential for maintaining maternal-fetal homeostasis, influencing processes such as nutrient exchange, hormone synthesis, trophoblast cell migration, and the function of smooth muscle cells in blood vessels. In preeclampsia, adverse conditions like hypoxia and oxidative stress result in the downregulation of ion, solute, and water transporters, impairing their function. This review focuses on membrane transporters involved in PE, discussing functional alterations and their physiological implications. The goal of this investigation is to enhance understanding of how dysregulation of ion and small molecule transporters contributes to the development and progression of preeclampsia, underscoring the importance of exploring these signaling pathways for potential therapeutic interventions.
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Preeclampsia , Humanos , Embarazo , Preeclampsia/metabolismo , Femenino , Placenta/metabolismo , Transporte Iónico , Animales , Proteínas de Transporte de Membrana/metabolismoRESUMEN
Background: The rising prevalence of fungal infections and challenges such as adverse effects and resistance against existing antifungal agents have driven the exploration of new antifungal substances. Methods: We specifically investigated naphthoquinones, known for their broad biological activities and promising antifungal capabilities. It specifically examined the effects of a particular naphthoquinone on the cellular components of Candida albicans ATCC 60193. The study also assessed cytotoxicity in MRC-5 cells, Artemia salina, and the seeds of tomatoes and arugula. Results: Among four tested naphthoquinones, 2,3-DBNQ (2,3-dibromonaphthalene-1,4-dione) was identified as highly effective, showing potent antifungal activity at concentrations between 1.56 and 6.25 µg mL-1. However, its cytotoxicity in MRC-5 cells (IC50 = 15.44 µM), complete mortality in A. salina at 50 µg mL-1, and significant seed germination inhibition suggest limitations for its clinical use. Conclusions: The findings indicate that primary antifungal mechanism of 2,3-DBNQ might involve disrupting fungal membrane permeability, which leads to increased nucleotide leakage. This insight underscores the need for further research to enhance the selectivity and safety of naphthoquinones for potential therapeutic applications.
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The COVID-19 pandemic has revealed weaknesses in healthcare systems and underscored the need for advanced antimicrobial materials. This study investigates the quaternization of agar, a seaweed-derived polysaccharide, and the development of electrospun membranes for air filtration in facemasks and biomedical applications. Using the betacoronavirus MHV-3 as a model, quaternized agar and membranes achieved a 90-99.99 % reduction in viral load, without associated cytotoxicity. The quaternization process reduced the viscosity of the solution from 1.19 ± 0.005 to 0.64 ± 0.005 Pa.s and consequently the electrospun fiber diameter ranged from 360 to 185 nm. Membranes synthesized based on polyvinyl alcohol and thermally cross-linked with citric acid exhibited lower water permeability. Avoiding organic solvents in the electrospinning technique ensured eco-friendly production. This approach offers a promising way to develop biocompatible and functional materials for healthcare and environmental applications.