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PURPOSE OF REVIEW: Anxiety disorders are highly prevalent conditions that have a detrimental impact on quality of life (QOL), particularly when left untreated. In the present review, we summarize recent literature, published within the last 3 years, on QOL in anxiety disorders, with a focus on factors that may play a role in the relationship between anxiety and QOL. RECENT FINDINGS: We organize our findings into four categories: (1) subjective distress, (2) behavioral responses, (3) functional impairment, and (4) clinical factors. Results indicate that greater anxiety symptom severity is linked with poorer QOL, and cognitive behavioral therapies for anxiety yield positive effects on QOL. Additional transdiagnostic mechanisms are highlighted, including anxiety sensitivity, distress tolerance, emotion regulation, and avoidant coping. We examine the role of functional impairment, and we discuss factors related to treatment, including comorbidity and longitudinal effects. We also consider early research from the COVID-19 pandemic. Understanding the underlying factors that contribute to QOL detriments provides important insight into the impact of anxiety disorders and identifies targets for enhancing QOL through treatment.
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COVID-19 , Calidad de Vida , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/terapia , Humanos , Pandemias , SARS-CoV-2RESUMEN
BACKGROUND: Our aim was to develop a brief cognitive behavioural therapy (CBT) protocol to augment treatment for social anxiety disorder (SAD). This protocol focused specifically upon fear of positive evaluation (FPE). To our knowledge, this is the first protocol that has been designed to systematically target FPE. AIMS: To test the feasibility of a brief (two-session) CBT protocol for FPE and report proof-of-principle data in the form of effect sizes. METHOD: Seven patients with a principal diagnosis of SAD were recruited to participate. Following a pre-treatment assessment, patients were randomized to either (a) an immediate CBT condition (n = 3), or (b) a comparable wait-list (WL) period (2 weeks; n = 4). Two WL patients also completed the CBT protocol following the WL period (delayed CBT condition). Patients completed follow-up assessments 1 week after completing the protocol. RESULTS: A total of five patients completed the brief, FPE-specific CBT protocol (two of the seven patients were wait-listed only and did not complete delayed CBT). All five patients completed the protocol and provided 1-week follow-up data. CBT patients demonstrated large reductions in FPE-related concerns as well as overall social anxiety symptoms, whereas WL patients demonstrated an increase in FPE-related concerns. CONCLUSIONS: Our brief FPE-specific CBT protocol is feasible to use and was associated with large FPE-specific and social anxiety symptom reductions. To our knowledge, this is the first treatment report that has focused on systematic treatment of FPE in patients with SAD. Our protocol warrants further controlled evaluation.
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Terapia Cognitivo-Conductual , Fobia Social , Miedo , Humanos , Fobia Social/terapia , Listas de EsperaRESUMEN
In the past decade, significant increases in surface water dissolved organic carbon (DOC) have been reported for large aquatic ecosystems of the Northern Hemisphere and have been attributed variously to global warming, altered hydrologic conditions, and atmospheric deposition, among other factors. We analyzed a 25-yr DOC record (1988-2012) available for a forested headwater stream in the United States and documented two distinct regimes of stream DOC trends. From 1988 to 2001, annual mean volume-weighted DOC concentration (DOC, mg L) and annual DOC flux (kg ha yr) declined by 34 and 56%, respectively. During 1997 to 2012, the decline in DOC and DOC flux increased by 141 and 165%, respectively. Declining DOC from 1988 to 2001 corresponded to a decline in growing season runoff, which has the potential to influence mobilization of DOC from uplands to streams. Increasing DOC from 1997 to 2012 corresponded to increased precipitation early in the growing season and to an increase in the number and intensity of short-duration fall storms capable of mobilizing long-accrued DOC from forest litter and soils. In contrast, total annual runoff declined throughout the period. Rising air temperature, atmospheric acid deposition, and nitrogen depositions did not offer any plausible explanation for the observed bidirectional annual trends of stream DOC. Our study highlights the critical role of long-term datasets and analyses for understanding the impacts of climate change on carbon and water cycles and associated functions of aquatic and terrestrial ecosystems.
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Carbono/análisis , Agricultura Forestal , Bosques , Ríos , Suelo , Sudeste de Estados UnidosRESUMEN
Promising renal replacement therapies include the development of a bioartificial kidney using functional human kidney cell models. In this study, human conditionally immortalized proximal tubular epithelial cell (ciPTEC) lines originating from kidney tissue (ciPTEC-T1 and ciPTEC-T2) were compared to ciPTEC previously isolated from urine (ciPTEC-U). Subclones of all ciPTEC isolates formed tight cell layers on Transwell inserts as determined by transepithelial resistance, inulin diffusion, E-cadherin expression and immunocytochemisty. Extracellular matrix genes collagen I and -IV α1 were highly present in both kidney tissue derived matured cell lines (p<0.001) compared to matured ciPTEC-U, whereas matured ciPTEC-U showed a more pronounced fibronectin I and laminin 5 gene expression (p<0.01 and p<0.05, respectively). Expression of the influx carrier Organic Cation Transporter 2 (OCT-2), and the efflux pumps P-glycoprotein (P-gp), Multidrug Resistance Protein 4 (MRP4) and Breast Cancer Resistance Protein (BCRP) were confirmed in the three cell lines using real-time PCR and Western blotting. The activities of OCT-2 and P-gp were sensitive to specific inhibition in all models (p<0.001). The highest activity of MRP4 and BCRP was demonstrated in ciPTEC-U (p<0.05). Finally, active albumin reabsorption was highest in ciPTEC-T2 (p<0.001), while Na(+)-dependent phosphate reabsorption was most abundant in ciPTEC-U (p<0.01). In conclusion, ciPTEC established from human urine or kidney tissue display comparable functional PTEC specific transporters and physiological characteristics, providing ideal human tools for bioartificial kidney development.
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Órganos Bioartificiales , Túbulos Renales Proximales/citología , Riñones Artificiales , Orina/citología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/biosíntesis , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/biosíntesis , Transportadoras de Casetes de Unión a ATP/metabolismo , Cadherinas/biosíntesis , Moléculas de Adhesión Celular/biosíntesis , Técnicas de Cultivo de Célula , Línea Celular , Colágeno Tipo I/biosíntesis , Colágeno Tipo I/metabolismo , Fibronectinas/biosíntesis , Humanos , Inulina/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/biosíntesis , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/metabolismo , Factor 2 de Transcripción de Unión a Octámeros/antagonistas & inhibidores , Factor 2 de Transcripción de Unión a Octámeros/biosíntesis , Factor 2 de Transcripción de Unión a Octámeros/metabolismo , Ingeniería de Tejidos , Migración Transendotelial y Transepitelial/fisiología , KalininaRESUMEN
During chronic kidney disease (CKD), drug metabolism is affected leading to changes in drug disposition. Furthermore, there is a progressive accumulation of uremic retention solutes due to impaired renal clearance. Here, we investigated whether uremic toxins can influence the metabolic functionality of human conditionally immortalized renal proximal tubule epithelial cells (ciPTEC) with the focus on UDP-glucuronosyltransferases (UGTs) and mitochondrial activity. Our results showed that ciPTEC express a wide variety of metabolic enzymes, including UGTs. These enzymes were functionally active as demonstrated by the glucuronidation of 7-hydroxycoumarin (7-OHC; K(m) of 12±2µM and a V(max) of 76±3pmol/min/mg) and p-cresol (K(m) of 33±13µM and a V(max) of 266±25pmol/min/mg). Furthermore, a wide variety of uremic toxins, including indole-3-acetic acid, indoxyl sulfate, phenylacetic acid and kynurenic acid, reduced 7-OHC glucuronidation with more than 30% as compared with controls (p<0.05), whereas UGT1A and UGT2B protein expressions remained unaltered. In addition, our results showed that several uremic toxins inhibited mitochondrial succinate dehydrogenase (i.e. complex II) activity with more than 20% as compared with controls (p<0.05). Moreover, indole-3-acetic acid decreased the reserve capacity of the electron transport system with 18% (p<0.03). In conclusion, this study shows that multiple uremic toxins inhibit UGT activity and mitochondrial activity in ciPTEC, thereby affecting the metabolic capacity of the kidney during CKD. This may have a significant impact on drug and uremic retention solute disposition in CKD patients.
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Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/metabolismo , Riñón/metabolismo , Mitocondrias/metabolismo , Uremia/metabolismo , Línea Celular , Cresoles/metabolismo , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/enzimología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/genética , Transporte de Electrón , Glucuronosiltransferasa/genética , Glucuronosiltransferasa/metabolismo , Humanos , Riñón/enzimología , Mitocondrias/enzimología , Mitocondrias/genética , Preparaciones Farmacéuticas/metabolismo , Succinato Deshidrogenasa/genética , Succinato Deshidrogenasa/metabolismo , Umbeliferonas/metabolismo , Uremia/enzimología , Uremia/genéticaRESUMEN
INTRODUCTION: In aromatic L-amino acid decarboxylase (AADC) deficiency, a neurotransmitter biosynthesis defect, paradoxical normal or increased levels of urinary dopamine have been reported. Genotype/phenotype correlations or alternative metabolic pathways may explain this remarkable finding, but were never studied systematically. METHODS: We studied the mutational spectrum and urinary dopamine levels in 20 patients with AADC-deficiency. Experimental procedures were designed to test for alternative metabolic pathways of dopamine production, which included alternative substrates (tyramine and 3-methoxytyrosine) and alternative enzymes (tyrosinase and CYP2D6). RESULTS/DISCUSSION: In 85% of the patients the finding of normal or increased urinary levels of dopamine was confirmed, but a relation with AADC genotype could not be identified. Renal microsomes containing CYP2D were able to convert tyramine into dopamine (3.0 nmol/min/g protein) but because of low plasma levels of tyramine this is an unlikely explanation for urinary dopamine excretion in AADC-deficiency. No evidence was found for the production of dopamine from 3-methoxytyrosine. Tyrosinase was not expressed in human kidney. CONCLUSION: Normal or increased levels of urinary dopamine are found in the majority of AADC-deficient patients. This finding can neither be explained by genotype/phenotype correlations nor by alternative metabolic pathways, although small amounts of dopamine may be formed via tyramine hydroxylation by renal CYP2D6. CYP2D6-mediated conversion of tyramine into dopamine might be an interesting target for the development of new therapeutic strategies in AADC-deficiency.
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Descarboxilasas de Aminoácido-L-Aromático/deficiencia , Descarboxilasas de Aminoácido-L-Aromático/metabolismo , Dopamina/orina , Adolescente , Adulto , Animales , Descarboxilasas de Aminoácido-L-Aromático/genética , Niño , Preescolar , Citocromo P-450 CYP2D6/metabolismo , Análisis Mutacional de ADN , Femenino , Estudios de Asociación Genética , Humanos , Lactante , Corteza Renal/enzimología , Masculino , Monofenol Monooxigenasa/genética , Monofenol Monooxigenasa/metabolismo , Ratas , Tiramina/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo , Adulto JovenRESUMEN
BACKGROUND: Despite high rates of smartphone ownership in psychiatric populations, there are very little data available characterizing smartphone use in individuals with mental illness. In particular, few studies have examined the interest and use of smartphones to support mental health. OBJECTIVE: This study aimed to (1) characterize general smartphone app and social media usage in an acute transdiagnostic psychiatric sample with high smartphone ownership, (2) characterize current engagement and interest in the use of smartphone apps to support mental health, and (3) test demographic and clinical predictors of smartphone use. METHODS: The survey was completed by all patients attending an adult partial hospital program, with no exclusion criteria. The primary outcomes were frequency of use of general and mental health smartphone apps (smartphone use survey) and the frequency of social media use and phone-checking behavior (mobile technology engagement scale). RESULTS: Overall, 322 patients (aged mean 33.49, SD 13.87 years; 57% female) reported that their most frequently used app functions were texting, email, and social media. Younger individuals reported more frequent use across most types of apps. Baseline depression and anxiety symptoms were not associated with the frequency of app use. Participants reported health care, calendar, and texting apps as most supportive of their mental health and social media apps as most negatively affecting their mental health. Most patients reported an interest in (73.9% [238/322]) and willingness to use (81.3% [262/322]) a smartphone app to monitor their mental health condition. Less than half (44%) of the patients currently had a mental health app downloaded on their smartphone, with mindfulness and meditation apps being the most common type. CONCLUSIONS: The high interest in and willingness to use mental health apps, paired with the only moderate current reported usage, indicate a potential unmet treatment opportunity in psychiatric populations. There is potential to optimize non-mental health-specific apps to better support the needs of those with mental illness and to design a new wave of mental health apps that match the needs of these populations as well as the way they use smartphones in daily life.
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Servicios de Salud Mental/tendencias , Aceptación de la Atención de Salud/estadística & datos numéricos , Medios de Comunicación Sociales/instrumentación , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aplicaciones Móviles , Medios de Comunicación Sociales/estadística & datos numéricos , Encuestas y CuestionariosRESUMEN
Drug-induced kidney injury is often observed in the clinics and can lead to long-term organ failure. In this work, we evaluated a novel in vitro system that aims at detecting whether compounds can cause renal proximal tubule damage in man. For this, we implemented organotypic cultures of human conditionally immortalized proximal tubule epithelial cells overexpressing the organic anion transporter 1 (ciPTEC-OAT1) in a three-channel OrganoPlate under microfluidic conditions. Cells were exposed to four known nephrotoxicants (cisplatin, tenofovir, cyclosporine A, and tobramycin). The effect on cell viability and NAG release into the medium was determined. A novel panel of four miRNAs (mir-21, mir-29a, mir-34a, and mir-192) was selected as potential biomarkers of proximal tubule damage. After nephrotoxicant treatment, miRNA levels in culture medium were earlier indicators than cell viability (WST-8 assay) and outperformed NAG for proximal tubule damage. In particular, mir-29a, mir-34a, and mir-192 were highly reproducible between experiments and across compounds, whereas mir-21 showed more variability. Moreover, similar data were obtained in two different laboratories, underlining the reproducibility and technical transferability of the results, a key requirement for the implementation of novel biomarkers. In conclusion, the selected miRNAs behaved like sensitive biomarkers of damage to tubular epithelial cells caused by several nephrotoxicity mechanisms. This biomarker panel, in combination with the 3D cultures of ciPTEC-OAT1 in the OrganoPlate, represents a novel tool for in vitro nephrotoxicity detection. These results pave the way for the application of miRNAs in longitudinal, time-course in vitro toxicity studies.
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Células Epiteliales/efectos de los fármacos , Enfermedades Renales/inducido químicamente , Túbulos Renales Proximales/efectos de los fármacos , MicroARNs/genética , Técnicas Analíticas Microfluídicas , Línea Celular Transformada , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células Epiteliales/metabolismo , Células Epiteliales/patología , Marcadores Genéticos , Humanos , Enfermedades Renales/genética , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/patología , MicroARNs/metabolismo , Prueba de Estudio Conceptual , Reproducibilidad de los Resultados , Medición de Riesgo , Factores de TiempoRESUMEN
The development of a biotechnological platform for the removal of waste products (e.g. uremic toxins), often bound to proteins in plasma, is a prerequisite to improve current treatment modalities for patients suffering from end stage renal disease (ESRD). Here, we present a newly designed bioengineered renal tubule capable of active uremic toxin secretion through the concerted action of essential renal transporters, viz. organic anion transporter-1 (OAT1), breast cancer resistance protein (BCRP) and multidrug resistance protein-4 (MRP4). Three-dimensional cell monolayer formation of human conditionally immortalized proximal tubule epithelial cells (ciPTEC) on biofunctionalized hollow fibers with maintained barrier function was demonstrated. Using a tailor made flow system, the secretory clearance of human serum albumin-bound uremic toxins, indoxyl sulfate and kynurenic acid, as well as albumin reabsorption across the renal tubule was confirmed. These functional bioengineered renal tubules are promising entities in renal replacement therapies and regenerative medicine, as well as in drug development programs.
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Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Túbulos Renales Proximales/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteínas de Neoplasias/metabolismo , Proteína 1 de Transporte de Anión Orgánico/metabolismo , Ingeniería de Tejidos , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Línea Celular , Humanos , Fallo Renal Crónico/genética , Fallo Renal Crónico/metabolismo , Fallo Renal Crónico/patología , Túbulos Renales Proximales/patología , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas de Neoplasias/genética , Proteína 1 de Transporte de Anión Orgánico/genéticaRESUMEN
BACKGROUND AND PURPOSE: Recently, two phase-II trials demonstrated improved renal function in critically ill patients with sepsis-associated acute kidney injury treated with the enzyme alkaline phosphatase. Here, we elucidated the dual active effect on renal protection of alkaline phosphatase. EXPERIMENTAL APPROACH: The effect of human recombinant alkaline phosphatase (recAP) on LPS-induced renal injury was studied in Sprague-Dawley rats. Renal function was assessed by transcutaneous measurement of FITC-sinistrin elimination in freely moving, awake rats. The mechanism of action of recAP was further investigated in vitro using conditionally immortalized human proximal tubular epithelial cells (ciPTEC). KEY RESULTS: In vivo, LPS administration significantly prolonged FITC-sinistrin half-life and increased fractional urea excretion, which was prevented by recAP co-administration. Moreover, recAP prevented LPS-induced increase in proximal tubule injury marker, kidney injury molecule-1 expression and excretion. In vitro, LPS-induced production of TNF-α, IL-6 and IL-8 was significantly attenuated by recAP. This effect was linked to dephosphorylation, as enzymatically inactive recAP had no effect on LPS-induced cytokine production. RecAP-mediated protection resulted in increased adenosine levels through dephosphorylation of LPS-induced extracellular ADP and ATP. Also, recAP attenuated LPS-induced increased expression of adenosine A2A receptor. However, the A2A receptor antagonist ZM-241385 did not diminish the effects of recAP. CONCLUSIONS AND IMPLICATIONS: These results indicate that the ability of recAP to reduce renal inflammation may account for the beneficial effect observed in septic acute kidney injury patients, and that dephosphorylation of ATP and LPS are responsible for this protective effect.
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Lesión Renal Aguda/metabolismo , Fosfatasa Alcalina/farmacología , Sustancias Protectoras/farmacología , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/tratamiento farmacológico , Lesión Renal Aguda/patología , Antagonistas de Receptores Adrenérgicos alfa 2/farmacología , Fosfatasa Alcalina/uso terapéutico , Animales , Células Cultivadas , Citocinas/metabolismo , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Fluoresceínas/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/patología , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/patología , Lipopolisacáridos , Masculino , Oligosacáridos/metabolismo , Sustancias Protectoras/uso terapéutico , Purinas/orina , Ratas Sprague-Dawley , Proteínas Recombinantes/farmacología , Triazinas/farmacología , Triazoles/farmacologíaRESUMEN
The bioartificial kidney (BAK) aims at improving dialysis by developing 'living membranes' for cells-aided removal of uremic metabolites. Here, unique human conditionally immortalized proximal tubule epithelial cell (ciPTEC) monolayers were cultured on biofunctionalized MicroPES (polyethersulfone) hollow fiber membranes (HFM) and functionally tested using microfluidics. Tight monolayer formation was demonstrated by abundant zonula occludens-1 (ZO-1) protein expression along the tight junctions of matured ciPTEC on HFM. A clear barrier function of the monolayer was confirmed by limited diffusion of FITC-inulin. The activity of the organic cation transporter 2 (OCT2) in ciPTEC was evaluated in real-time using a perfusion system by confocal microscopy using 4-(4-(dimethylamino)styryl)-N-methylpyridinium iodide (ASP(+)) as a fluorescent substrate. Initial ASP(+) uptake was inhibited by a cationic uremic metabolites mixture and by the histamine H2-receptor antagonist, cimetidine. In conclusion, a 'living membrane' of renal epithelial cells on MicroPES HFM with demonstrated active organic cation transport was successfully established as a first step in BAK engineering.
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Membranas Artificiales , Proteínas de Transporte de Catión Orgánico/metabolismo , Cationes/metabolismo , Adhesión Celular/efectos de los fármacos , Línea Celular , Cimetidina/farmacología , Células Epiteliales/citología , Células Epiteliales/metabolismo , Antagonistas de los Receptores H2 de la Histamina/farmacología , Humanos , Inmunohistoquímica , Transporte Iónico/efectos de los fármacos , Túbulos Renales Proximales/citología , Metilaminas/química , Metilaminas/metabolismo , Transportador 2 de Cátion Orgánico , Permeabilidad/efectos de los fármacos , Compuestos de Piridinio/química , Compuestos de Piridinio/metabolismo , Uniones Estrechas/metabolismo , Proteína de la Zonula Occludens-1/metabolismoRESUMEN
An amperometric flow injection immunoanalysis (FIIA) system based on an immunoreactor with immobilized biocomponents on a silica surface has been developed for the determination of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). In the antigen coating mode the hapten was immobilized and monoclonal primary antibody against 2,4-D together with alkaline phosphatase (AP)-labelled secondary antibody were used as sensing elements in a titration assay. In the antibody coating mode a biotinylated monoclonal antibody was immobilized on the surface of the immunoreactor and a 2,4-D-AP-conjugate was used for detection. For electrochemical measurements p-aminophenol enzymatically generated from p-aminophenyl phosphate was oxidized at a carbon working electrode at +150 mV versus Ag/AgCl. The system enabled the determination of 2,4-D in drinking water samples in the range from 0.2 to 70 micrograms/l. The whole system was computer controlled with a measuring time of 12 min for one determination.
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Ácido 2,4-Diclorofenoxiacético/análisis , Herbicidas/análisis , Inmunoensayo/instrumentación , Fosfatasa Alcalina , Animales , Anticuerpos Monoclonales , Relación Dosis-Respuesta Inmunológica , Electroquímica , Concentración de Iones de Hidrógeno , Técnicas para Inmunoenzimas , Ratones , Agua/análisis , Contaminantes del Agua/análisisRESUMEN
There is an increasing interest in the role of coagulation factor XIII (FXIII) in cardio- and cerebrovascular diseases. It has recently been reported that a common G-->T point mutation in the A-subunit gene of FXIII, which codes for a valine (val) to leucine (leu) change (FXIIIVal34Leu), is protective against thrombotic diseases but seems to increase the risk of intracerebral bleeding. We developed a colorimetric incorporation assay for detection of FXIII activity based on incorporation of 5-(biotinamido) pentylamine (BAPA) into fibrin or fibrinogen. With this new assay, we studied the effects of FXIIIVal34Leu mutation, plasma fibrinogen concentration and congenital FXIII deficiency on FXIII activity. There are no data available about the ability of different FXIII assays to detect altered activity in FXIIIVal34Leu genotypes. We therefore compared our results determined by the incorporation method with a commonly used photometric method based on ammonia release after cross-linking of glycine-ethylester to a specific glutamine containing peptide substrate. We also determined FXIII A-subunit antigen (Ag) levels using enzyme-linked immunosorbent assay (ELISA) technique. The FXIIIVal34Leu genotype could not be detected either by the photometric method nor by the FXIII A-subunit ELISA. The incorporation assay showed an increased specific FXIII activity in subjects possessing the leu allele. The photometric assay and ELISA gave similar results independent from genotype. In patients with congenital FXIII deficiency before and after substitution, however, ELISA and the incorporation assay gave similar results, whereas the photometric assay showed consistently higher values. Our results show that the incorporation assay, not the photometric assay based on ammonia release, can be used for detection of elevated activity in subjects with FXIIIVal34Leu. Because of specificity and over a wide range sensitivity, the assay can also be used for determination of FXIII deficiency and monitoring of FXIII substitution therapy.
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Factor XIII/metabolismo , Leucina/genética , Valina/genética , Aminas/farmacocinética , Sustitución de Aminoácidos , Amoníaco/metabolismo , Compuestos Cromogénicos/farmacocinética , Pruebas de Química Clínica/métodos , Pruebas de Química Clínica/normas , Ensayo de Inmunoadsorción Enzimática , Factor XIII/genética , Deficiencia del Factor XIII/sangre , Deficiencia del Factor XIII/congénito , Deficiencia del Factor XIII/genética , Fibrinógeno/metabolismo , Humanos , Cinética , Mutación Puntual , Sensibilidad y EspecificidadRESUMEN
BACKGROUND/AIMS: Cystinosis, a rare autosomal recessive disease, manifests with renal Fanconi syndrome during the first year of life. Interstitial damage is a major cause of renal failure in patients with cystinosis. We presume that albuminuria contributes to the development of renal failure in these patients. The aim of this study was to examine whether the administration of ACE inhibitor enalapril diminishes albuminuria in patients with cystinosis. METHODS: Five patients with cystinosis aged 4 - 9 years were studied. All patients had Fanconi syndrome and were treated with cysteamine. Median creatinine clearance was 48 ml/min/1.73 m2 (range 21 - 61). The excretion of albumin and alpha1 microglobulin as well as arterial blood pressure and serum creatinine were evaluated before and at 3 months on oral administration of enalapril (0.15 mg/kg once daily). RESULTS: At 3 months on enalapril, albuminuria decreased in all patients (1,042 vs 629 mg per 24 h, p < 0.05). The median reduction of albuminuria was 43% (range: 4 - 72%, p < 0.05). Urinary excretion of alpha1 microglobulin remained constant. Systolic blood pressure decreased from median 110 - 100 mmHg (p < 0.05), while diastolic blood pressure remained stable (median 60 mmHg). Creatinine clearance decreased from median 48 - 45 ml/min/1.73 m2 (p < 0.05) and returned to previous values after discontinuation of enalapril. CONCLUSION: ACE inhibitor enalapril diminishes albuminuria in patients with cystinosis and might be used in these patients in order to slow the progression of renal insufficiency attributed to proteinuria.
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Albuminuria/tratamiento farmacológico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Cistinosis/complicaciones , Enalapril/uso terapéutico , Albuminuria/etiología , Presión Sanguínea , Niño , Preescolar , Creatinina/sangre , Creatinina/orina , Humanos , Proteinuria/complicaciones , Estadísticas no Paramétricas , Resultado del TratamientoRESUMEN
Activated factor XIII (FXIIIa) plays an important role in the final stage of the coagulation cascade by covalent crosslinking of fibrin strands. As a transglutaminase FXIIIa catalyses the generation of intermolecular amide bonds between lysine and glutamine residues resulting in a complex three-dimensional clot structure. Enhanced clot stability is supported by covalent binding of cytosceleton factors like actin and myosin. Moreover, the clot is protected against premature lysis by the incorporation of fibrinolysis inhibitors like alpha(2)-antiplasmin and thrombin activatable fibrinolysis inhibitor (TAFI). A covalent crosslinking of the fibrin strands with extra-cellular matrix proteins like fibronectin, vitronectin, collagen and von Willebrand factor (vWF) immobilizes the clot at the site of injury. Moreover FXIII supports the healing process of damaged tissue. In this review assays for determination of FXIIIa activity, FXIII concentration and identification of the FXIIIVal34Leu polymorphism are shown.
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Factor XIII/análisis , Factor XIIIa/análisis , Coagulación Sanguínea/fisiología , Humanos , CinéticaRESUMEN
Cystinosis is an autosomal recessive disorder caused by an impaired transport of cystine out of lysosomes. The most severe infantile form of cystinosis starts with Fanconi syndrome at the age of 3-6 months. Untreated patients develop renal failure before the age of 10. The cystinosis gene (CTNS) maps to chromosome 17p13, spans 23 kb and is composed of 12 exons. CTNS encodes a 367 amino acid protein, cystinosin, which is a H(+)-driven lysosomal cystine transporter. It is enigmatic how lysosomal cystine accumulation induces the clinical symptoms. ATP depletion was demonstrated in an experimental model consisting of loading lysosomes with cystine dimethylester. The amino-thiol cysteamine depletes lysosomal cystine content by a disulfide-exchange reaction with cystine. Therapy with cysteamine should be administered as early as possible and continued after a renal transplantation as the extra renal damage still progresses. Improved life expectancy of cystinotic patients requires the attention of internists with a special interest for this rare disorder.
Asunto(s)
Cistinosis/genética , Glicoproteínas/genética , Proteínas de la Membrana/genética , Sistemas de Transporte de Aminoácidos Neutros , Cisteamina/administración & dosificación , Cistina/metabolismo , Cistinosis/tratamiento farmacológico , Cistinosis/fisiopatología , Síndrome de Fanconi/genética , Eliminación de Gen , Glicoproteínas/fisiología , Humanos , Proteínas de la Membrana/fisiología , Proteínas de Transporte de Membrana , Insuficiencia Renal/genéticaRESUMEN
With the world-wide increase of patients with renal failure, the development of functional renal replacement therapies have gained significant interest and novel technologies are rapidly evolving. Currently used renal replacement therapies insufficiently remove accumulating waste products, resulting in the uremic syndrome. A more preferred treatment option is kidney transplantation, but the shortage of donor organs and the increasing number of patients waiting for a transplant warrant the development of novel technologies. The bioartificial kidney (BAK) is such promising biotechnological approach to replace essential renal functions together with the active secretion of waste products. The development of the BAK requires a multidisciplinary approach and evolves at the intersection of regenerative medicine and renal replacement therapy. Here we provide a concise review embracing a compact historical overview of bioartificial kidney development and highlighting the current state-of-the-art, including implementation of living-membranes and the relevance of extracellular matrices. We focus further on the choice of relevant renal epithelial cell lines versus the use of stem cells and co-cultures that need to be implemented in a suitable device. Moreover, the future of the BAK in regenerative nephrology is discussed.
Asunto(s)
Bioprótesis , Biotecnología/métodos , Técnicas de Cocultivo/métodos , Riñones Artificiales , Ingeniería de Tejidos/métodos , Animales , Línea Celular , Células Epiteliales , Matriz Extracelular , Humanos , Ratones , Modelos Biológicos , Células Madre , PorcinosRESUMEN
The multidrug resistance gene 1 product, P-glycoprotein (P-gp), is expressed in several excretory organs, including the apical membrane of proximal tubules. After inducing acute renal failure, P-gp expression is upregulated and this might be a protective function by pumping out toxicants and harmful products of oxidative stress. We characterized renal function of P-gp knockout mice and studied its consequences in renal ischemic damage. Compared with wild-type mice, knockout mice have a lower glomerular filtration rate and renal plasma flow. An augmented urinary excretion of sodium, numerous amino acids, calcium, glucose, and low molecular weight proteins was observed along with an increased diuresis. A higher lithium plasma clearance in the knockout mice suggested proximal tubular dysfunction. Electron microscopy showed mitochondrial abnormalities in proximal tubular cells that could account for decreased adenosine triphosphate levels in the cortex. After inducing ischemia, wild-type mice showed a decrease in creatinine clearance and severe proximal tubular necrosis. In contrast, knockout mice had no signs of tubular damage. Our data indicate that P-gp knockout mice have impaired renal function but are protected against ischemic renal injury.