183 resultados para 1600-1681.
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Claudin-1 (CLDN1) is a structural tight junction (TJ) protein and is expressed in differentiating keratinocytes and Langerhans cells in the epidermis. Our objective was to identify immunoreactive CLDN1 in human epidermal Langerhans cells and to examine the pattern of epidermal Langerhans cells in genetic human CLDN1 deficiency [neonatal ichthyosis, sclerosing cholangitis (NISCH) syndrome]. Epidermal cells from healthy human skin labelled with CLDN1-specific antibodies were analysed by confocal laser immunofluorescence microscopy and flow cytometry. Skin biopsy sections of two patients with NISCH syndrome were stained with an antibody to CD1a expressed on epidermal Langerhans cells. Epidermal Langerhans cells and a subpopulation of keratinocytes from healthy skin were positive for CLDN1. The gross number and distribution of epidermal Langerhans cells of two patients with molecularly confirmed NISCH syndrome, however, was not grossly altered. Therefore, CLDN1 is unlikely to play a critical role in migration of Langerhans cells (or their precursors) to the epidermis or their positioning within the epidermis. Our findings do not exclude a role of this TJ molecule once Langerhans cells have left the epidermis for draining lymph nodes.
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Nella mia tesi di dottorato mi concentro sul poema di Lucrezia Marinelli, L'Enrico, ovvero Bisanzio acquistato, pubblicato a Venezia nel 1635, indagando le strategie messe in atto dall'autrice per rivisitare il genere epico in un'ottica di riscatto femminile. Rispetto al canone epico e, in particolare, al modello di riferimento - la Gerusalemme liberata del Tasso - le vicende nodali sono, infatti, riscritte da un punto di vista chiaramente femminile. Pur occupandomi principalmente dell'opera di Marinelli, in alcuni casi nel corso del mio lavoro propongo dei confronti con altri poemi epici e cavallereschi prodotti da donne - in particolare I tredici canti del Floridoro di Moderata Fonte (1581) - volti a mostrare come le scrittrici avessero degli intenti comuni, dialogando in maniera critica con i modelli maschili da cui, tuttavia, traggono ispirazione. Nei primi capitoli del mio lavoro prendo in esame alcuni personaggi tradizionali dell'epica (le guerriere, la maga, ...) presenti ne L'Enrico e ne ripercorro gli episodi topici (le sortite notturne, l'eroe sull'isola, ...) dimostrando come, pur inserendosi coerentemente nel genere epico, siano caratterizzati in modo sostanzialmente diverso rispetto alla precedente tradizione maschile. Il primo capitolo si concentra sulle figure di guerriere, le quali presentano - rispetto ai precedenti modelli - differenze notevoli: non si lasciano coinvolgere in vicende amorose e non finiscono per essere sottomesse o uccise da un uomo, mantenendo così coerentemente intatti i valori di forza e indipendenza. Neppure la maga sull'isola - presa in esame nel capitolo dedicato alle Altre figure di donne idealizzate - è coinvolta in vicende sentimentali o caratterizzata sensualmente. L'autrice la rappresenta, non alla stregua di una tentatrice al servizio delle forze del male, ma come una donna colta, casta e disposta ad aiutare il cavaliere naufragato sulla sua isola. Nello stesso capitolo sono indagate anche altre figure femminili idealizzate, per taluni aspetti meno innovative, ma ugualmente interessanti: la Vergine, la personificazione di Venezia e la Musa. Queste rappresentazioni dal carattere iconico, presentano, infatti, diverse caratteristiche in comune con i personaggi più attivi del poema, le guerriere e la maga. Il capitolo Delle pene e delle tragedie amorose è dedicato all'amore e ai suoi esiti tragici. Le figure di donna coinvolte sono le madri, le mogli e Idillia, in cui è riconoscibile il personaggio topico della "damigella in difficoltà". Queste protagoniste, destinate a soffrire perché abbandonate dall'uomo che amano - il quale sente più forte il richiamo della guerra rispetto a quello dell'amore - servono da exempla, dimostrando che attaccamento affettivo e dipendenza conducono inesorabilmente all'infelicità. Rispetto al canone epico Marinelli riscatta alcune figure femminili, permettendo alle sue guerriere di prendersi la rivincita, vendicando la morte di eroine quali Camilla e Clorinda. Conseguentemente, alcuni guerrieri sono destinati a morire per mano di una donna. Nel quarto capitolo, mi concentro proprio su La sconfitta degli eroi, mettendo in luce come l'autrice proponga una sua personale regola del contrappasso, volta a cambiare (e addirittura invertire) le sorti dei personaggi che animano il suo poema. Questi aspetti risultano essere ancora più significativi se confrontati con l'opera - data alle stampe per la prima volta nel 1600 - intitolata Nobiltà et eccellenza delle donne. In questo trattato Marinelli sosteneva la superiorità del genere femminile su quello maschile. Alcune delle posizioni assunte nello scritto giovanile sono confermate dai personaggi e dalle vicende che animano l'Enrico. Confronti puntuali fra trattato e poema epico sono effettuati nell'ultimo capitolo del mio lavoro, sottolineando come fra le due opere vi siano delle affinità volte a confermare l'eccellenza delle donne.
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Uromodulin is expressed exclusively in the thick ascending limb and is the most abundant protein excreted in normal urine. Variants in UMOD, which encodes uromodulin, are associated with renal function, and urinary uromodulin levels may be a biomarker for kidney disease. However, the genetic factors regulating uromodulin excretion are unknown. We conducted a meta-analysis of urinary uromodulin levels to identify associated common genetic variants in the general population. We included 10,884 individuals of European descent from three genetic isolates and three urban cohorts. Each study measured uromodulin indexed to creatinine and conducted linear regression analysis of approximately 2.5 million single nucleotide polymorphisms using an additive model. We also tested whether variants in genes expressed in the thick ascending limb associate with uromodulin levels. rs12917707, located near UMOD and previously associated with renal function and CKD, had the strongest association with urinary uromodulin levels (P<0.001). In all cohorts, carriers of a G allele of this variant had higher uromodulin levels than noncarriers did (geometric means 10.24, 14.05, and 17.67 μg/g creatinine for zero, one, or two copies of the G allele). rs12446492 in the adjacent gene PDILT (protein disulfide isomerase-like, testis expressed) also reached genome-wide significance (P<0.001). Regarding genes expressed in the thick ascending limb, variants in KCNJ1, SORL1, and CAB39 associated with urinary uromodulin levels. These data indicate that common variants in the UMOD promoter region may influence urinary uromodulin levels. They also provide insights into uromodulin biology and the association of UMOD variants with renal function.
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Regulation of renal Na(+) transport is essential for controlling blood pressure, as well as Na(+) and K(+) homeostasis. Aldosterone stimulates Na(+) reabsorption by the Na(+)-Cl(-) cotransporter (NCC) in the distal convoluted tubule (DCT) and by the epithelial Na(+) channel (ENaC) in the late DCT, connecting tubule, and collecting duct. Aldosterone increases ENaC expression by inhibiting the channel's ubiquitylation and degradation; aldosterone promotes serum-glucocorticoid-regulated kinase SGK1-mediated phosphorylation of the ubiquitin-protein ligase Nedd4-2 on serine 328, which prevents the Nedd4-2/ENaC interaction. It is important to note that aldosterone increases NCC protein expression by an unknown post-translational mechanism. Here, we present evidence that Nedd4-2 coimmunoprecipitated with NCC and stimulated NCC ubiquitylation at the surface of transfected HEK293 cells. In Xenopus laevis oocytes, coexpression of NCC with wild-type Nedd4-2, but not its catalytically inactive mutant, strongly decreased NCC activity and surface expression. SGK1 prevented this inhibition in a kinase-dependent manner. Furthermore, deficiency of Nedd4-2 in the renal tubules of mice and in cultured mDCT(15) cells upregulated NCC. In contrast to ENaC, Nedd4-2-mediated inhibition of NCC did not require the PY-like motif of NCC. Moreover, the mutation of Nedd4-2 at either serine 328 or 222 did not affect SGK1 action, and mutation at both sites enhanced Nedd4-2 activity and abolished SGK1-dependent inhibition. Taken together, these results suggest that aldosterone modulates NCC protein expression via a pathway involving SGK1 and Nedd4-2 and provides an explanation for the well-known aldosterone-induced increase in NCC protein expression.
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The skin is essential for survival and protects our body against biological attacks, physical stress, chemical injury, water loss, ultraviolet radiation and immunological impairment. The epidermal barrier constitutes the primordial frontline of this defense established during terminal differentiation. During this complex process proliferating basal keratinocytes become suprabasally mitotically inactive and move through four epidermal layers (basal, spinous, granular and layer, stratum corneum) constantly adapting to the needs of the respective cell layer. As a result, squamous keratinocytes contain polymerized keratin intermediate filament bundles and a water-retaining matrix surrounded by the cross-linked cornified cell envelope (CE) with ceramide lipids attached on the outer surface. These cells are concomitantly insulated by intercellular lipid lamellae and hold together by corneodesmosmes. Many proteins essential for epidermal differentiation are encoded by genes clustered on chromosomal human region 1q21. These genes constitute the 'epidermal differentiation complex' (EDC), which is divided on the basis of common gene and protein structures, in three gene families: (i) CE precursors, (ii) S100A and (iii) S100 fused genes. EDC protein expression is regulated in a gene and tissue-specific manner by a pool of transcription factors. Among them, Klf4, Grhl3 and Arnt are essential, and their deletion in mice is lethal. The importance of the EDC is further reflected by human diseases: FLG mutations are the strongest risk factor for atopic dermatitis (AD) and for AD-associated asthma, and faulty CE formation caused by TG1 deficiency causes life-threatening lamellar ichthyosis. Here, we review the EDC genes and the progress in this field.
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D-lactic acid in urine originates mainly from bacterial production in the intestinal tract. Increased D-lactate excretion as observed in patients affected by short bowel syndrome or necrotizing enterocolitis reflects D-lactic overproduction. Therefore, there is a need for a reliable and sensitive method able to detect D-lactic acid even at subclinical elevation levels. A new and highly sensitive method for the simultaneous determination of L- and D-lactic acid by a two-step procedure has been developed. This method is based on the concentration of lactic acid enantiomers from urine by supported liquid extraction followed by high-performance liquid chromatography-tandem mass spectrometry. The separation was achieved by the use of an Astec Chirobiotic? R chiral column under isocratic conditions. The calibration curves were linear over the ranges of 2-400 and 0.5-100 µmol/L respectively for L- and D-lactic acid. The limit of detection of D-lactic acid was 0.125 µmol/L and its limit of quantification was 0.5 µmol/L. The overall accuracy and precision were well within 10% of the nominal values. The developed method is suitable for production of reference values in children and could be applied for accurate routine analysis.
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Dans les sociétés contemporaines axées sur le savoir, plus grande sera la proportion de leur population détentrice d'une formation supérieure et engagée en recherche, plus avancé sera leur développement économique et social.1,2 Par contre, dans ces sociétés, le vieillissement de la population, l'importance ccordée aux soins de santé axés sur les maladies chroniques et les coûts financiers de ceux-ci exercent une forte pression sur les systèmes de santé. Les nterventions doivent donc être les plus efficaces possible, avec un rapport coût/efficacité optimal. Cela requiert que les infirmières soient capables d'oeuvrer en pratique avancée, c'est-à-dire capables de développer, implémenter et évaluer des approches cliniques infirmières basées sur des preuves, de tester de nouvelles interventions potentiellement plus efficientes et de promouvoir un programme de recherche portant explicitement sur l'amélioration de la qualité et sécurité des soins en contexte d'interdisciplinarité.
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1. (1-36)-NPY is a vasoconstrictor peptide widely distributed in sympathetic nerve terminals. This peptide exerts an inhibitory action on renin release induced by various stimuli. Post-synaptic neuropeptide Y (NPY) receptors show a high affinity for (1-36)-NPY as well as for the agonist (Pro34)-NPY, while presynaptic receptors bind preferentially (13-36)-NPY. 2. This study was undertaken to assess whether the NPY induced renin suppression in awake normotensive rats infused with the beta-adrenoceptor stimulant isoproterenol is mediated by activation of pre- or post-synaptic receptors. 3. Non-pressor doses of (1-36)-NPY and (Pro34)-NPY markedly attenuated the renin secretion triggered by isoproterenol whereas (13-36)-NPY had no effect. This suggests that the effect of NPY on renin release is due to the stimulation of post-synaptic receptors. However it remains unknown whether NPY acts directly on juxtaglomerular cells or indirectly by modifying intraglomerular haemodynamics.
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Identifying the geographic distribution of populations is a basic, yet crucial step in many fundamental and applied ecological projects, as it provides key information on which many subsequent analyses depend. However, this task is often costly and time consuming, especially where rare species are concerned and where most sampling designs generally prove inefficient. At the same time, rare species are those for which distribution data are most needed for their conservation to be effective. To enhance fieldwork sampling, model-based sampling (MBS) uses predictions from species distribution models: when looking for the species in areas of high habitat suitability, chances should be higher to find them. We thoroughly tested the efficiency of MBS by conducting an important survey in the Swiss Alps, assessing the detection rate of three rare and five common plant species. For each species, habitat suitability maps were produced following an ensemble modeling framework combining two spatial resolutions and two modeling techniques. We tested the efficiency of MBS and the accuracy of our models by sampling 240 sites in the field (30 sitesx8 species). Across all species, the MBS approach proved to be effective. In particular, the MBS design strictly led to the discovery of six sites of presence of one rare plant, increasing chances to find this species from 0 to 50%. For common species, MBS doubled the new population discovery rates as compared to random sampling. Habitat suitability maps coming from the combination of four individual modeling methods predicted well the species' distribution and more accurately than the individual models. As a conclusion, using MBS for fieldwork could efficiently help in increasing our knowledge of rare species distribution. More generally, we recommend using habitat suitability models to support conservation plans.
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Proteases control many vital aspects of humoral and cellular immune responses, including the maturation of cytokines and the killing of target cells. Recently, it has become evident that triggering of the T-cell receptor controls T-cell proliferation through proteases such as mucosa-associated lymphoid tissue 1 (MALT1) and Caspase-8 that act both as adapters and enzymes. Here, we discuss the role of these and other proteases that are relevant to the control of the T-cell response and represent interesting targets of therapeutic immunomodulation.
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The exchange of information during interactions of T cells with dendritic cells, B cells or other T cells regulates the course of T, B and DC-cell activation and their differentiation into effector cells. The tumor necrosis factor superfamily member LIGHT (homologous to lymphotoxin, exhibits inducible expression and competes with HSV glycoprotein D for binding to herpesvirus entry mediator, a receptor expressed on T lymphocytes) is transiently expressed upon T cell activation and modulates CD8 T cell-mediated alloreactive responses upon herpes virus entry mediator (HVEM) and lymphotoxin β receptor (LTβR) engagement. LIGHT-deficient mice, or WT mice treated with LIGHT-targeting decoy receptors HVEM-Ig, LTβR-Ig or sDcR3-Ig, exhibit prolonged graft survival compared to untreated controls, suggesting that LIGHT modulates the course and severity of graft rejection. Therefore, targeting the interaction of LIGHT with HVEM and/or LTβR using recombinant soluble decoy receptors or monoclonal antibodies represent an innovative therapeutic strategy for the prevention and treatment of allograft rejection and for the promotion of donor-specific tolerance.
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This Clinical Practice Guideline (CPG) has been developed to assist physicians and other healthcare providers in the diagnosis and management of patients with Wilson's disease. The goal is to describe a number of generally accepted approaches for diagnosis, prevention, and treatment of Wilson's disease. Recommendations are based on a systematic literature review in the Medline (PubMed version), Embase (Dialog version), and the Cochrane Library databases using entries from 1966 to 2011. The Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) system used in other EASL CPGs was used and set against the somewhat different grading system used in the AASLD guidelines (Table 1A and B). Unfortunately, there is not a single randomized controlled trial conducted in Wilson's disease which has an optimal design. Thus, it is impossible to assign a high or even a moderate quality of evidence to any of the questions dealt with in these guidelines. The evaluation is mostly based on large case series which have been reported within the last decades.
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OBJECTIVES: This systematic review aims to assess the risks (both thromboembolic and bleeding) of an oral anticoagulation therapy (OAT) patient undergoing implant therapy and to provide a management protocol to patients under OAT undergoing implant therapy. MATERIAL AND METHODS: Medline, Cochrane Data Base of Systematic Reviews, the Cochrane Central Register of Controlled Trials and EMBASE (from 1980 to December 2008) were searched for English-language articles published between 1966 and 2008. This search was completed by a hand research accessing the references cited in all identified publications. RESULTS: Nineteen studies were identified reporting outcomes after oral surgery procedures (mostly dental extractions in patients on OAT following different management protocols and haemostatic therapies). Five studies were randomized-controlled trials (RCTs), 11 were controlled clinical trials (CCTs) and three were prospective case series. The OAT management strategies as well as the protocols during and after surgery were different. This heterogeneity prevented any possible data aggregation and synthesis. The results from these studies are very homogeneous, reporting minor bleeding in very few patients, without a significant difference between the OAT patients who continue with the vitamin K antagonists vs. the patients who stopped this medication before surgery. These post-operative bleeding events were controlled only with local haemostatic measures: tranexamic acid mouthwashes, gelatine sponges and cellulose gauzes's application were effective. Post-operative bleeding did not correlate with the international normalised ratio (INR) status. In none of the studies was a thromboembolic event reported. CONCLUSIONS: OAT patients (INR 2-4) who do not discontinue the AC medication do not have a significantly higher risk of post-operative bleeding than non-OAT patients and they also do not have a higher risk of post-operative bleeding than OAT patients who discontinue the medication. In patients with OAT (INR 2-4) without discontinuation, topical haemostatic agents were effective in preventing post-operative bleeding. OAT discontinuation is not recommended for minor oral surgery, such as single tooth extraction or implant placement, provided that this does not involve autogenous bone grafts, extensive flaps or osteotomy preparations extending outside the bony envelope. Evidence does not support that dental implant placement in patients on OAT is contraindicated.
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We assessed the impact of antiviral prophylaxis and preemptive therapy on the incidence and outcomes of cytomegalovirus (CMV) disease in a nationwide prospective cohort of solid organ transplant recipients. Risk factors associated with CMV disease and graft failure-free survival were analyzed using Cox regression models. One thousand two hundred thirty-nine patients transplanted from May 2008 until March 2011 were included; 466 (38%) patients received CMV prophylaxis and 522 (42%) patients were managed preemptively. Overall incidence of CMV disease was 6.05% and was linked to CMV serostatus (D+/R- vs. R+, hazard ratio [HR] 5.36 [95% CI 3.14-9.14], pâeuro0/00<âeuro0/000.001). No difference in the incidence of CMV disease was observed in patients receiving antiviral prophylaxis as compared to the preemptive approach (HR 1.16 [95% CI 0.63-2.17], pâeuro0/00=âeuro0/000.63). CMV disease was not associated with a lower graft failure-free survival (HR 1.27 [95% CI 0.64-2.53], pâeuro0/00=âeuro0/000.50). Nevertheless, patients followed by the preemptive approach had an inferior graft failure-free survival after a median of 1.05 years of follow-up (HR 1.63 [95% CI 1.01-2.64], pâeuro0/00=âeuro0/000.044). The incidence of CMV disease in this cohort was low and not influenced by the preventive strategy used. However, patients on CMV prophylaxis were more likely to be free from graft failure.
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This study investigated the contribution of sources and establishment characteristics, on the exposure to fine particulate matter (PM(2.5)) in the non-smoking sections of bars, cafes, and restaurants in central Zurich. PM(2.5)-exposure was determined with a nephelometer. A random sample of hospitality establishments was investigated on all weekdays, from morning until midnight. Each visit lasted 30 min. Numbers of smokers and other sources, such as candles and cooking processes, were recorded, as were seats, open windows, and open doors. Ambient air pollution data were obtained from public authorities. Data were analysed using robust MM regression. Over 14 warm, sunny days, 102 establishments were measured. Average establishment PM(2.5) concentrations were 64.7 microg/m(3) (s.d. = 73.2 microg/m(3), 30-min maximum 452.2 microg/m(3)). PM(2.5) was significantly associated with the number of smokers, percentage of seats occupied by smokers, and outdoor PM. Each smoker increased PM(2.5) on average by 15 microg/m(3). No associations were found with other sources, open doors or open windows. Bars had more smoking guests and showed significantly higher concentrations than restaurants and cafes. Smokers were the most important PM(2.5)-source in hospitality establishments, while outdoor PM defined the baseline. Concentrations are expected to be even higher during colder, unpleasant times of the year. PRACTICAL IMPLICATIONS: Smokers and ambient air pollution are the most important sources of fine airborne particulate matter (PM(2.5)) in the non-smoking sections of bars, restaurants, and cafes. Other sources do not significantly contribute to PM(2.5)-levels, while opening doors and windows is not an efficient means of removing pollutants. First, this demonstrates the impact that even a few smokers can have in affecting particle levels. Second, it implies that creating non-smoking sections, and using natural ventilation, is not sufficient to bring PM(2.5) to levels that imply no harm for employees and non-smoking clients. [Authors]