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Hereditary spastic paraplegia is a neurological condition characterized by predominant axonal degeneration in long spinal tracts, leading to weakness and spasticity in the lower limbs. The nicotinamide adenine dinucleotide (NAD+)-consuming enzyme SARM1 has emerged as a key executioner of axonal degeneration upon nerve transection and in some neuropathies. An increase in the nicotinamide mononucleotide/NAD+ ratio activates SARM1, causing catastrophic NAD+ depletion and axonal degeneration. However, the role of SARM1 in the pathogenesis of hereditary spastic paraplegia has not been investigated. Here, we report an enhanced mouse model for hereditary spastic paraplegia caused by mutations in SPG7. The eSpg7 knockout mouse carries a deletion in both Spg7 and Afg3l1, a redundant homologue expressed in mice but not in humans. The eSpg7 knockout mice recapitulate the phenotypic features of human patients, showing progressive symptoms of spastic-ataxia and degeneration of axons in the spinal cord as well as the cerebellum. We show that the lack of SPG7 rewires the mitochondrial proteome in both tissues, leading to an early onset decrease in mito-ribosomal subunits and a remodelling of mitochondrial solute carriers and transporters. To interrogate mechanisms leading to axonal degeneration in this mouse model, we explored the involvement of SARM1. Deletion of SARM1 delays the appearance of ataxic signs, rescues mitochondrial swelling and axonal degeneration of cerebellar granule cells and dampens neuroinflammation in the cerebellum. The loss of SARM1 also prevents endoplasmic reticulum abnormalities in long spinal cord axons, but does not halt the degeneration of these axons. Our data thus reveal a neuron-specific interplay between SARM1 and mitochondrial dysfunction caused by lack of SPG7 in hereditary spastic paraplegia.
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Paraplejía Espástica Hereditaria , Animales , Humanos , Ratones , Proteínas del Dominio Armadillo/genética , ATPasas Asociadas con Actividades Celulares Diversas , Axones/patología , Cerebelo , Proteínas del Citoesqueleto/genética , Metaloendopeptidasas/genética , Metaloendopeptidasas/metabolismo , NAD , Paraplejía Espástica Hereditaria/genéticaRESUMEN
Urine, a common source of biological markers in biomedical research and clinical diagnosis, has recently generated a new wave of interest. It has recently become a focus of study due to the presence of its content of extracellular vesicles (EVs). These uEVs have been found to reflect physiological and pathological conditions in kidney, urothelial, and prostate tissue and can illustrate further molecular processes, leading to a rapid expansion of research in this field In this work, we present the advantages of an immunoaffinity-based method for uEVs' isolation with respect to the gold standard purification approach performed by differential ultracentrifugation [in terms of purity and antigen presence. The immunoaffinity method was made feasible by combining specific antibodies with a functionalized polymethacrylate polymer. Flow cytometry indicated a significant fluorescence shift, validating the presence of the markers (CD9, CD63, CD81) and confirming the effectiveness of the isolation method. Microscopy evaluations have shown that the morphology of the vesicles remained intact and corresponded to the expected shapes and dimensions of uEVs. The described protocol is inexpensive, fast, easy to process, has good reproducibility, and can be applied to further biological samples.
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Biomarcadores , Vesículas Extracelulares , Vesículas Extracelulares/metabolismo , Humanos , Citometría de Flujo/métodos , Masculino , Tetraspanina 30/metabolismoRESUMEN
Prostate-specific membrane antigen (PSMA) and caveolin-1 are membrane proteins that are overexpressed in prostate cancer (PCa) and are involved in tumor growth and increase in aggressiveness. The aim of the present study is therefore to evaluate PSMA and caveolin-1 proteins from plasma exosomes as effective liquid biopsy biomarkers for PCa. This study included 39 patients with PCa and 33 with benign prostatic hyperplasia (BPH). The shape and size of the exosomes were confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analysis. Immunogold analysis showed that PSMA is localized to the membrane of exosomes isolated from the plasma of both groups of participants. The relative protein levels of PSMA and caveolin-1 in the plasma exosomes of PCa and BPH patients were determined by Western blot analysis. The relative level of the analyzed plasma exosomal proteins was compared between PCa and BPH patients and the relevance of the exosomal PSMA and caveoin-1 level to the clinicopathological parameters in PCa was investigated. The analysis performed showed an enrichment of exosomal PSMA in the plasma of PCa patients compared to the exosomes of men with BPH. The level of exosomal caveolin-1 in plasma was significantly higher in PCa patients with high PSA levels, clinical-stage T3 or T4 and in the group of PCa patients with aggressive PCa compared to favorable clinicopathological features or tumor aggressiveness. Plasma exosomes may serve as a suitable object for the identification of potential biomarkers for the early diagnosis and prognosis of PCa as well as carriers of therapeutic agents in precision medicine of PCa treatment.
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Hiperplasia Prostática , Neoplasias de la Próstata , Masculino , Humanos , Hiperplasia Prostática/metabolismo , Próstata/patología , Caveolina 1/metabolismo , Serbia , Biomarcadores de Tumor/metabolismo , Neoplasias de la Próstata/metabolismo , Antígeno Prostático Específico/metabolismoRESUMEN
Secondary polyphenol metabolites, urolithins (UROs), have anti-oxidative, anti-inflammatory, and antidiabetic properties. Therefore, their biological activity relies on blood transport via human serum albumin (HSA) and tissue distribution. The main goal we set was to investigate the interaction between HSA and different URO (URO A, URO B, URO C, URO D, and glucuronidated URO A and B) using a combination of multi-spectroscopic instrumental and in silico approaches. The fluorescence spectroscopy revealed that URO can quench the naturally occurring fluorescence of HSA in a concentration-dependent manner. The HSA fluorescence was quenched by both a static and dynamic mechanism. The results showed that free UROs bind to HSA with higher affinity than their conjugated forms. CD spectroscopy and FTIR revealed that the alpha-helical structure of HSA is preserved. The calculated Gibbs free energy change indicates that the URO-HSA complex forms spontaneously. There is a single binding site on the HSA surface. The molecular docking results indicated that unconjugated Uro binds to Sudlow I, while their conjugation affects this binding site, so in the conjugated form, they bind to the cleft. Docking experiments indicate that all UROs are capable of binding to both thyroxine recognition sites of ligand-bound HSA proteins. Examining interactions under the following conditions (298 K, 303 K, and 310 K, pH 7.4) is of great importance for determining the pharmacokinetics of these bioactive compounds, as the obtained results can be used as a basis for modulating the potential dosing regimen.
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Simulación del Acoplamiento Molecular , Polifenoles , Unión Proteica , Albúmina Sérica Humana , Humanos , Polifenoles/química , Polifenoles/metabolismo , Albúmina Sérica Humana/química , Albúmina Sérica Humana/metabolismo , Sitios de Unión , Espectrometría de Fluorescencia , Dicroismo Circular , Termodinámica , Espectroscopía Infrarroja por Transformada de Fourier , CumarinasRESUMEN
OBJECTIVE: This study aimed to evaluate the dental pulp responses to recombinant human erythropoietin (rhEPO) and/or mineral trioxide aggregate (MTA) in pulp capping of inflamed dental pulp in vivo. MATERIALS AND METHODS: In accordance with ARRIVE guidelines, pulp inflammation was induced by exposing the maxillary first molars (n = 64) of Wistar rats (n = 32) to the oral environment for two days. The exposed pulps were randomly assigned four groups based on the pulp capping material: rhEPO, MTA, MTA + rhEPO, or an inert membrane. An additional eight rats formed the healthy control group. After four weeks, the animals were euthanized, and histological, qRT-PCR, and spectrophotometric techniques were employed to analyze the left maxillary segments, right first maxillary molars, and blood samples, respectively. Statistical significance was set at p < 0.05 and < 0.001. RESULTS: Pulp capping with rhEPO, MTA, or MTA + rhEPO resulted in lower inflammation and higher mineralization scores compared to untreated control. MTA + rhEPO group exhibited significantly decreased expression of tumor necrosis factor-alpha, and interleukin 1-beta, while MTA group showed substantially reduced expression of interferon-gamma. Both rhEPO and MTA + rhEPO groups presented elevated dentin matrix protein 1 levels compared to untreated control. Furthermore, pulp capping with rhEPO and/or MTA led to increased transforming growth factor-beta 1 expression and reductions of pro-inflammatory/immunoregulatory cytokine ratios and prooxidative markers. Pulp capping with rhEPO also resulted in increase of systemic antioxidative stress markers. CONCLUSION: Capping with rhEPO or MTA + rhEPO resulted in a favorable effect that was similar or even superior to that of MTA.
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Mitochondria are essential organelles found in every eukaryotic cell, required to convert food into usable energy. Therefore, it is not surprising that mutations in either mtDNA or nuclear DNA-encoded genes of mitochondrial proteins cause diseases affecting the oxidative phosphorylation system, which are heterogeneous from a clinical, genetic, biochemical and molecular perspective and can affect patients at any age. Despite all this, it is surprising that our understanding of the mechanisms governing mitochondrial gene expression and its associated pathologies remain superficial and therapeutic interventions largely unexplored. We recently showed that loss of the mitochondrial matrix protease caseinolytic protease proteolytic subunit (CLPP) ameliorates phenotypes in cells characterized by defects in oxidative phosphorylation maintenance. Here, we build upon this finding by showing that CLPP depletion is indeed beneficial in vivo for various types of neuronal populations, including Purkinje cells in the cerebellum and cortical and hippocampal neurons in the forebrain, as it strongly improves distinct phenotypes of mitochondria encephalopathy, driven by the deficiency of the mitochondrial aspartyl tRNA synthase DARS2. In the absence of CLPP, neurodegeneration of DARS2-deficient neurons is delayed as they present milder oxidative phosphorylation dysfunction. This in turn leads to a decreased neuroinflammatory response and significantly improved motor functions in both double-deficient models (Purkinje cell-specific or forebrain neuron-specific Dars2/Clpp double knockout mice). We propose that diminished turnover of respiratory complex I caused by the loss of CLPP is behind the improved phenotype in Dars2/Clpp double knockout animals, even though this intervention might not restore respiratory complex I activity but rather improve mitochondrial cristae morphology or help maintain the NAD+/NADH ratio inside mitochondria. These results also open the possibility of targeting CLPP activity in many other mitochondrial encephalopathies characterized by respiratory complex I instability.
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Endopeptidasa Clp/metabolismo , Péptido Hidrolasas , Animales , Endopeptidasa Clp/genética , Humanos , Ratones , Ratones Noqueados , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Péptido Hidrolasas/metabolismoRESUMEN
Biotechnological and biomedical applications of antibodies have been on a steady rise since the 1980s. As unique and highly specific bioreagents, monoclonal antibodies (mAbs) have been widely exploited and approved as therapeutic agents. However, the use of mAbs has limitations for therapeutic applications. Antibody fragments (AbFs) with preserved antigen-binding sites have a significant potential to overcome the disadvantages of conventional mAbs, such as heterogeneous tissue distribution after systemic administration, especially in solid tumors, and Fc-mediated bystander activation of the immune system. AbFs possess better biodistribution coefficient due to lower molecular weight. They preserve the functional features of mAbs, such as antigen specificity and binding, while at the same time, ensuring much better tissue penetration. An additional benefit of AbFs is the possibility of their production in bacterial and yeast cells due to the small size, more robust structure, and lack of posttranslational modifications. In this review, we described current approaches to the AbF production with recent examples of AbF synthesis in bacterial and yeast expression systems and methods for the production optimization.
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Melatonin (MLT), earlier described as an effective anti-inflammatory agent, could be a beneficial adjunctive drug for sepsis treatment. This study aimed to determine the effects of MLT application in lipopolysaccharide (LPS)-induced sepsis in Wistar rats by determining the levels of liver tissue pro-inflammatory cytokines (TNF-α, IL-6) and NF-κB as well as hematological parameters indicating the state of sepsis. Additionally, an immunohistological analysis of CD14 molecule expression was conducted. Our research demonstrated that treatment with MLT prevented an LPS-induced increase in pro-inflammatory cytokines TNF-α and IL-6 and NF-κB levels, and in the neutrophil to lymphocyte ratio (NLR). On the other hand, MLT prevented a decrease in the blood lymphocyte number induced by LPS administration. Also, treatment with MLT decreased the liver tissue expression of the CD14 molecule observed after sepsis induction. In summary, in rats with LPS-induced sepsis, MLT was shown to be a significant anti-inflammatory agent with the potential to change the liver's immunological marker expression, thus ameliorating liver function.
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Melatonina , Sepsis , Ratas , Animales , Ratas Wistar , Melatonina/farmacología , Melatonina/uso terapéutico , Interleucina-6 , Lipopolisacáridos/toxicidad , FN-kappa B , Factor de Necrosis Tumoral alfa/genética , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Hígado , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Citocinas , Receptores de Lipopolisacáridos , Modelos AnimalesRESUMEN
This study aimed to evaluate the effect of direct pulp capping on the expression of erythropoietin (Epo) and Epo-receptor (Epor) genes in relation to the expression of inflammatory and osteogenic genes in rat pulp. Dental pulps of the first maxillary molars of Wistar Albino rats were exposed and capped with either calcium hydroxide or mineral trioxide aggregate, or were left untreated. After 4 wk, animals were euthanized, and maxillae were prepared for histological and real-time polymerase chain reaction analysis. Histological scores of pulp inflammation and mineralization, and relative expressions of Epo, Epor, inflammatory cytokines, and pulp osteogenic genes were evaluated. The capped pulps showed higher expressions of Epo, while the untreated pulps had the highest expression of Epor. Both calcium hydroxide and mineral trioxide aggregate downregulated the expression of tumor necrosis factor alpha compared to untreated controls, and upregulated transforming growth factor beta compared to healthy controls. Alkaline phosphatase expression was significantly higher in experimental groups. Relative expression of Epo negatively correlated with pulp inflammation, and positively correlated with pulp mineralization. Pulp exposure promoted expression of Epor and pro-inflammatory cytokines, while pulp capping promoted expression of Epo, alkaline phosphatase, and downregulated Epor and pro-inflammatory cytokines.
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Recubrimiento de la Pulpa Dental , Eritropoyetina/metabolismo , Receptores de Eritropoyetina/metabolismo , Fosfatasa Alcalina/metabolismo , Compuestos de Aluminio/farmacología , Animales , Hidróxido de Calcio/farmacología , Pulpa Dental , Combinación de Medicamentos , Inflamación/patología , Óxidos/farmacología , Ratas , Ratas Wistar , Silicatos/farmacología , Factor de Crecimiento Transformador beta , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Considerable exploration has been done in recent years to exploit the reported inherent dielectric contrast between healthy and malignant tissues for a range of medical applications. In particular, microwave technologies have been investigated towards new diagnostic medical tools. To assess the performance and detection capabilities of such systems, tissue-mimicking phantoms are designed for controlled laboratory experiments. We here report phantoms developed to dielectrically represent malign skin lesions such as liposarcoma and nonsyndromic multiple basal cell carcinoma. Further, in order to provide a range of anatomically realistic scenarios, and provide meaningful comparison between different phantoms, cancer-mimicking lesions are inserted into two different types of skin phantoms with varying tumor-skin geometries. These configurations were measured with a microwave dielectric probe (0.5-26.5 GHz), yielding insight into factors that could affect the performance of diagnostic and detection tools.
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Carcinoma Basocelular , Neoplasias Cutáneas , Humanos , Microondas , Fantasmas de Imagen , PielRESUMEN
Background: This study aimed to investigate the clinical form, risk factors, and outcomes of patients with COVID-19 and Clostridioides difficile co-infections. Methods: This retrospective study (2 September 2021-1 April 2022) included all patients with Clostridioides difficile infection (CDI) and COVID-19 infection who were admitted to the Covid Hospital of the University Clinical Center of Vojvodina. Results: A total of 5124 COVID-19 patients were admitted to the Covid Hospital, and 326 of them (6.36%) developed hospital-onset CDI. Of those, 326 of the CDI patients (88.65%) were older than 65 years. The median time of CDI onset was 12.88 days. Previous hospitalizations showed 69.93% of CDI patients compared to 38.81% in the non-CDI group (p = 0.029). The concomitant antibiotics exposure was higher among the CDI group versus the non-CDI group (88.65% vs. 68.42%, p = 0.037). Albumin levels were ≤ 25 g/L among 39.57% of the CDI patients and 21.71% in the non-CDI patients (p = 0.021). The clinical manifestations of CDI ranged from mild diarrhea (26.9%) to severe diarrhea (63.49%) and a complicated form of colitis (9.81%). Regarding outcomes, 79.14% of the CDI patients recovered and 20.86% had fatal outcomes in-hospital. Although a minority of the patients were in the non-CDI group, the difference in mortality rate between the CDI and non-CDI group was not statistically significant (20.86% vs. 15.13%, p = 0.097). Conclusions: Elderly patients on concomitant antibiotic treatments with hypoalbuminemia and with previous healthcare exposures were the most affected by COVID-19 and CD co-infections.
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COVID-19 , Clostridioides difficile , Infecciones por Clostridium , Coinfección , Anciano , Albúminas , Antibacterianos/uso terapéutico , COVID-19/complicaciones , Infecciones por Clostridium/complicaciones , Infecciones por Clostridium/tratamiento farmacológico , Infecciones por Clostridium/epidemiología , Coinfección/epidemiología , Diarrea/epidemiología , Diarrea/etiología , Hospitales , Humanos , Estudios Retrospectivos , Serbia/epidemiología , Universidades , YugoslaviaRESUMEN
Actinidin (Act d 1), a highly abundant cysteine protease from kiwifruit, is one of the major contributors to the development of kiwifruit allergy. Many studies have focused on the optimization of Act d 1 purification and its role in the development of food allergies. Testing on cell culture monolayers is a common step in the elucidation of food allergen sensitization. In the case of cysteine proteases, an additional activation step with L-cysteine is required before the testing. Hence, we aimed to evaluate whether L-cysteine already present in commonly used cell culture media would suffice for Act d 1 activation. Successfully activated Act d 1 (98.1% of proteolytic activity, as compared to L-cysteine activated Act d 1) was further tested in two commonly used 2D model systems (Caco-2 and HEK293 cells) to evaluate its role on the mRNA expression of cytokines involved in the innate immunity (IL-1ß, IL-6, TNFα, TSLP). Furthermore, the contribution of Act d 1 in the promotion of inflammation through regulation of inducible nitric oxide synthase (iNOS) mRNA expression was also examined. These results demonstrate that activation of cysteine proteases can be achieved without previous enzyme incubation in L-cysteine -containing solution. Act d 1 incubated in cell culture medium was able to modulate gene expression of pro-inflammatory cytokines when tested on two model systems of the epithelial barrier.
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Actinidia/metabolismo , Cisteína Endopeptidasas/metabolismo , Proteasas de Cisteína/metabolismo , Células CACO-2 , Medios de Cultivo/química , Cisteína/farmacología , Proteasas de Cisteína/genética , Hipersensibilidad a los Alimentos/inmunología , Hipersensibilidad a los Alimentos/metabolismo , Frutas/genética , Células HEK293 , HumanosRESUMEN
BACKGROUND: Differential diagnosis of diabetes insipidus is challenging. The most reliable approach is hypertonic saline-stimulated copeptin measurements. However, this test is based on the induction of hypernatraemia and requires close monitoring of plasma sodium concentrations. Arginine-stimulated copeptin measurements might provide an alternative, simple, and safe test. METHODS: In this prospective diagnostic study, we recruited a development cohort from University Hospital Basel, Basel, Switzerland, and a validation cohort from five centres in Basel, Aarau, Luzern, Bern, and St Gallen, Switzerland, and the University Hospital Würzburg, Würzburg, Germany. For both cohorts, patients were eligible for inclusion if they were aged 18 years or older, were newly referred with polyuria (>50 mL/kg bodyweight per day) or had a known diagnosis of central diabetes insipidus or primary polydipsia. We also recruited a comparator cohort of healthy controls in parallel to each cohort, comprising adults (aged 18 years and older, with normal drinking habits, and no history of polyuria) and children who underwent arginine stimulation to diagnose growth hormone deficiency (children were only included in the comparator cohort to the development cohort as proof of concept). Patients and healthy controls underwent arginine stimulation with measurement of plasma copeptin at baseline and 30, 45, 60, 90, and 120 min. The primary objective in the development cohort was to determine the diagnostic accuracy of plasma copeptin concentrations to discriminate between diabetes insipidus and primary polydipsia, and in the validation cohort was to confirm those results. Adverse effects of the test were monitored in all participants, with tolerability of the test rated using a visual analogue scale (VAS) that ranged from no (0) to maximum (10) discomfort. This trial is registered with ClinicalTrials.gov, number NCT00757276. FINDINGS: Between May 24, 2013, and Jan 11, 2017, 52 patients were enrolled in the development cohort (12 [23%] with complete diabetes insipidus, nine [17%] with partial diabetes insipidus, and 31 [60%] with primary polydipsia) alongside 20 healthy adults and 42 child controls. Between Oct 24, 2017, and June 27, 2018, 46 patients were enrolled in the validation cohort (12 [26%] with complete diabetes insipidus, seven [15%] with partial diabetes insipidus, and 27 [59%] with primary polydipsia) alongside 30 healthy adult controls (two patients in this cohort were excluded from the main analysis because of early vomiting during the test). In the pooled patient and control datasets, median arginine-stimulated copeptin concentrations increased in healthy adult controls (from 5·2 pM [IQR 3·3-10·9] to a maximum of 9·8 pM [6·4-19·6]) and in participants with primary polydipsia (from 3·6 pM [IQR 2·4-5·7] to a maximum of 7·9 pM [5·1-11·8]), but only minimally in those with diabetes insipidus (2·1 pM [IQR 1·9-2·7] to a maximum of 2·5 pM [1·9-3·1]). In the development cohort, a cutoff of 3·5 pM at 60 min provided the highest diagnostic accuracy of 94% (95% CI 84-98). The accuracy of this cutoff in the validation cohort was 86% (95% CI 73-94). By pooling the data from both cohorts, an optimal accuracy of 93% (95% CI 86-97) was reached at a cutoff of 3·8 pM copeptin at 60 min (sensitivity 93%, 95% CI 86-98; specificity 92%, 95% CI 84-100). The test was safe and well tolerated, with median VAS scores of 3·5 (IQR 2-4) in patients with diabetes insipidus, 3 (2-4) in those with primary polydipsia, 1 (1-3) in healthy adults, and 1 (0-5) in healthy children in the pooled participant dataset. INTERPRETATION: Arginine-stimulated copeptin measurements are an innovative test for diabetes insipidus with high diagnostic accuracy, and could be a simplified, novel, and safe diagnostic approach to diabetes insipidus in clinical practice. FUNDING: Swiss National Science Foundation and University Hospital Basel.
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Arginina/administración & dosificación , Diabetes Insípida Nefrogénica/diagnóstico , Glicopéptidos/sangre , Adulto , Anciano , Estudios de Casos y Controles , Diabetes Insípida Nefrogénica/sangre , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Adulto JovenRESUMEN
BACKGROUND: The thorough understanding of the physiological and pathological processes mediated by extracellular vesicles (EVs) is challenged by purification methods which are cumbersome, not reproducible, or insufficient to yield homogeneous material. Chromatography based on both ion-exchange and immune-capture can represent an effective method to improve EV purification and successive analysis. METHODS: Cell culture supernatant was used as a model sample for assessing the capacity of anion-exchange chromatography to separate distinct EV fractions and to isolate nanobodies by direct panning on whole EVs to recover binders specific for the native conformation of EV-surface epitopes and suitable to develop EV immune-capture reagents. RESULTS: Anion-exchange chromatography of cell culture supernatant separated distinct protein-containing fractions and all of them were positive for CD9, a biomarker associated to some EVs. This suggested the existence of several EV fractions but did not help in separating EVs from other contaminants. We further isolated several nanobodies instrumental for implementing immune-affinity protocols. These were able to immobilize EVs from both cell culture supernatant and biological samples, to be used in ELISA, flow-cytometry, and immune-purification. CONCLUSIONS: Here we report the first successful isolation of anti-EV nanobodies for the use in immunoaffinity-based EV capture by panning a phage library directly on partially purified EVs. This achievement paves the way for the application of direct EV panning for the discovery of novel antibody-vesicle surface biomarker pairs and represents the preliminary requirement for the development of selective immune-capture that, in combination with anion-exchange chromatography, can simplify the systematic stratification of EV sub-populations and their individual characterization.
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Vesículas Extracelulares/química , Inmunoensayo/métodos , Anticuerpos de Dominio Único/aislamiento & purificación , Cromatografía por Intercambio Iónico/métodos , Medios de Cultivo/química , Epítopos/química , Epítopos/inmunología , Vesículas Extracelulares/inmunología , Vesículas Extracelulares/metabolismo , Humanos , Proteínas , Anticuerpos de Dominio Único/análisisRESUMEN
The exclusive properties of monolithic supports enable fast mass transfer, high porosity, low back pressure, easy preparation process and miniaturisation, and the availability of different chemistries make them particularly suitable materials for high-throughput (HTP) protein and peptide separation. In this review recent advances in monolith-based chromatographic supports for HTP screening of protein and peptide samples are presented and their application in HTP sample preparation (separation, enrichment, depletion, proteolytic digestion) for HTP proteomics is discussed. Development and applications of different monolithic capillary columns in HTP MS-based bottom-up and top-down proteomics are overviewed. By discussing the chromatographic conditions and the mass spectrometric data acquisition conditions an attempt is made to present currently demonstrated capacities of monolithic capillary columns for HTP identification and quantification of proteins and peptides from complex biological samples by MS-based proteomics. Some recent advances in basic monolith technology of importance for proteomics are also discussed.
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Cromatografía Liquida , Ensayos Analíticos de Alto Rendimiento/métodos , Péptidos , Proteínas , Proteómica/métodos , Cromatografía Liquida/instrumentación , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Péptidos/análisis , Péptidos/química , Péptidos/aislamiento & purificación , Proteínas/análisis , Proteínas/química , Proteínas/aislamiento & purificaciónRESUMEN
Inaccurate estimation of average dielectric properties can have a tangible impact on microwave radar-based breast images. Despite this, recent patient imaging studies have used a fixed estimate although this is known to vary from patient to patient. Parameter search algorithms are a promising technique for estimating the average dielectric properties from the reconstructed microwave images themselves without additional hardware. In this work, qualities of accurately reconstructed images are identified from point spread functions. As the qualities of accurately reconstructed microwave images are similar to the qualities of focused microscopic and photographic images, this work proposes the use of focal quality metrics for average dielectric property estimation. The robustness of the parameter search is evaluated using experimental dielectrically heterogeneous phantoms on the three-dimensional volumetric image. Based on a very broad initial estimate of the average dielectric properties, this paper shows how these metrics can be used as suitable fitness functions in parameter search algorithms to reconstruct clear and focused microwave radar images.
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Microondas , Algoritmos , Mama , Neoplasias de la Mama , Humanos , Fantasmas de Imagen , RadarRESUMEN
Urolithins (UROs) are metabolites derived from ellagic acid (EA) and ellagitannins (ETs) by gut microbiota after consumption of different ETs. The health effects attributed to UROs are numerous and diverse, ranging from antimalarial properties to anticancer activities and regulation of gene expression. The aim of this work was at assessing the effect of URO-A; -B; -C; -D on the oxidative status of colon epithelium using as a model colorectal adenocarcinoma cell line (Caco-2). No significant cytotoxic effects of UROs was noted, with the applied treatments. Supplementation of cell growth medium with a mixture of UROs decreased the level of intracellular reactive oxygen species both after short- and long-term exposure. UROs also affected the activity of antioxidative enzymes within the cell, especially catalase. CONCLUSIONS: At concentrations reached in the lumen of the gut, UROs can exert beneficial effects on the cells by decreasing oxidative stress thus preventing the damage caused by reactive oxygen species.
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Adenocarcinoma/metabolismo , Neoplasias Colorrectales/metabolismo , Estrés Oxidativo/efectos de los fármacos , Agentes Urológicos/farmacología , Antioxidantes/metabolismo , Células CACO-2 , Humanos , Estructura Molecular , Estrés Oxidativo/fisiología , Agentes Urológicos/administración & dosificación , Agentes Urológicos/químicaRESUMEN
AIMS/HYPOTHESIS: We have recently shown that adjunct prednisone shortens the time taken to reach clinical stability (time to clinical stability, TTCS) in patients with community-acquired pneumonia (CAP). Considering the hyperglycaemic effects of prednisone, there are concerns about the efficacy and safety of this therapy for diabetic patients with CAP. Our objective was to evaluate whether diabetes and/or hyperglycaemia on admission to hospital has an influence on the effect of corticosteroids on outcome in a well-defined cohort of patients with CAP. METHODS: This is a preplanned subanalysis of a prospective randomised, double-blind placebo-controlled multicentre trial. Patients aged 18 years or older with CAP were eligible and were recruited from seven tertiary care hospitals in Switzerland within 24 h of presentation. Patients were randomised (1:1 ratio) to receive either 50 mg of prednisone daily for 7 days or placebo. Allocation was concealed with a prespecified computer-generated randomisation list. Patients, treating physicians, investigators and data assessors were masked to treatment allocation. The primary endpoint was TTCS; secondary endpoints were length of stay, mortality, duration of antibiotic treatment, CAP complications and new insulin requirement at day 30. Furthermore, we analysed whether these endpoints were influenced by a glycaemic dysregulation during the study time. RESULTS: Of 802 patients randomised (n = 402 in the prednisone, n = 400 in the placebo group), 726 patients were treated per protocol and included in this analysis (n = 362 in the prednisone, n = 364 in the placebo group). Nineteen per cent of 726 patients had diabetes mellitus (n = 66 in the prednisone group, n = 72 in the placebo group). Adjunct prednisone shortened TTCS in diabetic and non-diabetic patients (HR 1.65 [95% CI 1.16, 2.35], p = 0.007; 1.30 [95% CI 1.10, 1.53], p = 0.002) with no evidence for effect modification by diabetes in interaction analysis (p = 0.44). No difference was found in other clinically relevant endpoints. Although adjunct prednisone was associated with glycaemic dysregulation, this did not translate into worse clinical outcomes in either group, and there was no difference in secondary endpoints. CONCLUSIONS/INTERPRETATION: The benefit of adjunct prednisone in CAP patients is also valid for those with diabetes or hyperglycaemia on admission. Hyperglycaemia in diabetic patients or due to adjunct prednisone did not have a negative effect on outcome. TRIAL REGISTRATION: ClinicalTrials.gov NCT00973154 FUNDING : This study was supported by a grant from the Swiss National Foundation and by the Nora van Meeuwen Häfliger Stiftung and the Gottfried Julia Bangerter-Rhyner Stiftung.
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Diabetes Mellitus/sangre , Diabetes Mellitus/tratamiento farmacológico , Hiperglucemia/sangre , Hiperglucemia/tratamiento farmacológico , Neumonía/sangre , Neumonía/tratamiento farmacológico , Prednisona/efectos adversos , Prednisona/uso terapéutico , Anciano , Anciano de 80 o más Años , Antiinflamatorios/efectos adversos , Antiinflamatorios/uso terapéutico , Infecciones Comunitarias Adquiridas , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
CDC25 homology domain (CDC25-HD) containing Guanine Nucleotide Exchange Factors (GEFs) initiate signalling by small G-proteins of the Ras-family. Each GEF acts on a small subset of the G-proteins only, thus providing signalling selectivity. Rlf is a GEF with selectivity for the G-proteins RalA and RalB. Here the crystal structure of Rlf in complex with Ral is determined. The Rlf·Ral complex crystallised into two different crystal forms, which represent different steps of the exchange reaction. Thereby general insight in the CDC25-HD catalysed nucleotide exchange is obtained. In addition, the basis for the selectivity of the interaction is investigated. The exchange activity is monitored by the use of recombinant proteins. Selectivity determinants in the binding interface are identified and confirmed by a mutational study.
Asunto(s)
Proteínas de Drosophila/química , Factores de Transcripción/química , Proteínas de Unión al GTP ral/química , Cristalografía por Rayos X , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Factores de Intercambio de Guanina Nucleótido , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Conformación Proteica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Unión al GTP ral/genética , Proteínas de Unión al GTP ral/metabolismoRESUMEN
This article is the first thorough study of average population exposure to third generation network (3G)-induced electromagnetic fields (EMFs), from both uplink and downlink radio emissions in different countries, geographical areas, and for different wireless device usages. Indeed, previous publications in the framework of exposure to EMFs generally focused on individual exposure coming from either personal devices or base stations. Results, derived from device usage statistics collected in France and Serbia, show a strong heterogeneity of exposure, both in time, that is, the traffic distribution over 24 h was found highly variable, and space, that is, the exposure to 3G networks in France was found to be roughly two times higher than in Serbia. Such heterogeneity is further explained based on real data and network architecture. Among those results, authors show that, contrary to popular belief, exposure to 3G EMFs is dominated by uplink radio emissions, resulting from voice and data traffic, and average population EMF exposure differs from one geographical area to another, as well as from one country to another, due to the different cellular network architectures and variability of mobile usage. Bioelectromagnetics. 37:382-390, 2016. © 2016 Wiley Periodicals, Inc.