1000 resultados para 610.3
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Helicobacter pylori infects the human gastric mucosa causing a chronic infection that is the primary risk factor for gastric cancer development. Recent studies demonstrate that H. pylori promotes tolerogenic dendritic cell (DC) development indicating that this bacterium evades the host immune response. However, the signaling pathways involved in modulating DC activation during infection remain unclear. Here, we report that H. pylori infection activated the signal transducer and activator of transcription 3 (STAT3) pathway in murine bone marrow-derived DCs (BMDCs) and splenic DCs isolated ex vivo. Isogenic cagA-, cagE-, vacA- and urease-mutants exhibited levels of phosphoSTAT3 that were comparable to in the wild-type (WT) parent strain. H. pylori-infected BMDCs produced increased immunosuppressive IL-10, which activated STAT3 in an autocrine/paracrine fashion. Neutralization of IL-10 prevented H. pylori-mediated STAT3 activation in both BMDCs and splenic DCs. In addition, anti-IL-10 treatment of infected H. pylori-BMDCs was associated with increased CD86 and MHC II expression and enhanced proinflammatory IL-1β cytokine secretion. Finally, increased CD86 and MHC II expression was detected in H. pylori-infected STAT3 knockout DCs when compared to WT controls. Together, these results demonstrate that H. pylori infection induces IL-10 secretion in DCs, which activates STAT3, thereby modulating DC maturation and reducing IL-1β secretion. These findings identify a host molecular mechanism by which H. pylori can manipulate the innate immune response to potentially favor chronic infection and promote carcinogenesis. © 2014 S. Karger AG, Basel.
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Alveolar echinococcosis (AE), caused by larva stage of Echinococcus multilocularis, is one of the lethal parasitic diseases of man and a major public health problem in many countries in the northern hemisphere. When the living conditions and habits in Turkey were considered in terms of relation with the life cycle of the parasite, it was suggested that AE has been much more common than reported mainly from the Eastern Anatolia region of Turkey. Since in vitro serologic diagnosis tests with high specificity for AE have not been used in our country, most of the cases with liver lesions were misdiagnosed by radiological investigations as malignancies. The aim of this study was to evaluate the diagnostic value of the in-house ELISA methods developed by using three different antigens (EgHF, Em2, EmII/3-10) in the serological diagnosis of AE. The study samples included a total of 100 sera provided by Bern University Parasitology Institute where samples were obtained from patients with helminthiasis and all were confirmed by clinical, parasitological and/or histopathological means. Ten samples from each of the cases infected by E.multilocularis, E.granulosus, Taenia solium, Wuchereria bancrofti, Strongyloides stercolaris, Ascaris lumbricoides, Toxocara canis, Trichinella spiralis, Fasciola hepatica and Schistosoma haematobium were studied. In the study, EgHF (E.granulosus hydatid fluid) antigens were prepared in our laboratory from the liver cyst fluids of sheeps with cystic echinococcosis, however Em2 (E.multilocularis metacestode-purified laminated layer) and EmII/3-10 (E.multilocularis recombinant protoscolex tegument) antigens were provided by Bern University Parasitology Institute. Flat bottom ELISA plates were covered with EgHF, Em2 and EmII/3-10 antigens in the concentrations of 2.5 µg, 1 µg and 0.18 µg per well, respectively, and all sera were tested by EgHF-ELISA, Em2-ELISA and EmII/3-10-ELISA methods. For each tests, the samples which were reactive above the cut-off value (mean OD of negative controls+2 SD) were accepted as positive. The sensitivity of the ELISA tests performed with EgHF, Em2 and Em2II/3-10 antigens were estimated as 100%, 90% and 90%, respectively, whereas the specificity were 63%, 91% and 91%, respectively. When Em2-ELISA and EmII/3-10-ELISA tests were evaluated together, the specificity increased to 96%. Our data indicated that the highest sensitivity (100% with EgHF-ELISA) and specificity (96% with Em2-ELISA + EmII/3-10-ELISA) for the serodiagnosis of AE can be achieved by the combined use of the ELISA tests with three different antigens. It was concluded that the early and accurate diagnosis of AE in our country which is endemic for that disease, could be supported by the use of highly specific serological tests such as Em2-ELISA ve EmII/3-10-ELISA contributing radiological data.
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BACKGROUND After heart transplantation (HTx), the interindividual pharmacokinetic variability of immunosuppressive drugs represents a major therapeutic challenge due to the narrow therapeutic window between over-immunosuppression causing toxicity and under-immunosuppression leading to graft rejection. Although genetic polymorphisms have been shown to influence pharmacokinetics of immunosuppressants, data in the context of HTx are scarce. We thus assessed the role of genetic variation in CYP3A4, CYP3A5, POR, NR1I2, and ABCB1 acting jointly in immunosuppressive drug pathways in tacrolimus (TAC) and ciclosporin (CSA) dose requirement in HTx recipients. METHODS Associations between 7 functional genetic variants and blood dose-adjusted trough (C0) concentrations of TAC and CSA at 1, 3, 6, and 12 months after HTx were evaluated in cohorts of 52 and 45 patients, respectively. RESULTS Compared with CYP3A5 nonexpressors (*3/*3 genotype), CYP3A5 expressors (*1/*3 or *1/*1 genotype) required around 2.2- to 2.6-fold higher daily TAC doses to reach the targeted C0 concentration at all studied time points (P ≤ 0.003). Additionally, the POR*28 variant carriers showed higher dose-adjusted TAC-C0 concentrations at all time points resulting in significant differences at 3 (P = 0.025) and 6 months (P = 0.047) after HTx. No significant associations were observed between the genetic variants and the CSA dose requirement. CONCLUSIONS The CYP3A5*3 variant has a major influence on the required TAC dose in HTx recipients, whereas the POR*28 may additionally contribute to the observed variability. These results support the importance of genetic markers in TAC dose optimization after HTx.
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BACKGROUND Patients with muscle-invasive urothelial carcinoma of the bladder have poor survival after cystectomy. The EORTC 30994 trial aimed to compare immediate versus deferred cisplatin-based combination chemotherapy after radical cystectomy in patients with pT3-pT4 or N+ M0 urothelial carcinoma of the bladder. METHODS This intergroup, open-label, randomised, phase 3 trial recruited patients from hospitals across Europe and Canada. Eligible patients had histologically proven urothelial carcinoma of the bladder, pT3-pT4 disease or node positive (pN1-3) M0 disease after radical cystectomy and bilateral lymphadenectomy, with no evidence of any microscopic residual disease. Within 90 days of cystectomy, patients were centrally randomly assigned (1:1) by minimisation to either immediate adjuvant chemotherapy (four cycles of gemcitabine plus cisplatin, high-dose methotrexate, vinblastine, doxorubicin, and cisplatin [high-dose MVAC], or MVAC) or six cycles of deferred chemotherapy at relapse, with stratification for institution, pT category, and lymph node status according to the number of nodes dissected. Neither patients nor investigators were masked. Overall survival was the primary endpoint; all analyses were by intention to treat. The trial was closed after recruitment of 284 of the planned 660 patients. This trial is registered with ClinicalTrials.gov, number NCT00028756. FINDINGS From April 29, 2002, to Aug 14, 2008, 284 patients were randomly assigned (141 to immediate treatment and 143 to deferred treatment), and followed up until the data cutoff of Aug 21, 2013. After a median follow-up of 7·0 years (IQR 5·2-8·7), 66 (47%) of 141 patients in the immediate treatment group had died compared with 82 (57%) of 143 in the deferred treatment group. No significant improvement in overall survival was noted with immediate treatment when compared with deferred treatment (adjusted HR 0·78, 95% CI 0·56-1·08; p=0·13). Immediate treatment significantly prolonged progression-free survival compared with deferred treatment (HR 0·54, 95% CI 0·4-0·73, p<0·0001), with 5-year progression-free survival of 47·6% (95% CI 38·8-55·9) in the immediate treatment group and 31·8% (24·2-39·6) in the deferred treatment group. Grade 3-4 myelosuppression was reported in 33 (26%) of 128 patients who received treatment in the immediate chemotherapy group versus 24 (35%) of 68 patients who received treatment in the deferred chemotherapy group, neutropenia occurred in 49 (38%) versus 36 (53%) patients, respectively, and thrombocytopenia in 36 (28%) versus 26 (38%). Two patients died due to toxicity, one in each group. INTERPRETATION Our data did not show a significant improvement in overall survival with immediate versus deferred chemotherapy after radical cystectomy and bilateral lymphadenectomy for patients with muscle-invasive urothelial carcinoma. However, the trial is limited in power, and it is possible that some subgroups of patients might still benefit from immediate chemotherapy. An updated individual patient data meta-analysis and biomarker research are needed to further elucidate the potential for survival benefit in subgroups of patients. FUNDING Lilly, Canadian Cancer Society Research.
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We report the largest international study on Glanzmann thrombasthenia (GT), an inherited bleeding disorder where defects of the ITGA2B and ITGB3 genes cause quantitative or qualitative defects of the αIIbβ3 integrin, a key mediator of platelet aggregation. Sequencing of the coding regions and splice sites of both genes in members of 76 affected families identified 78 genetic variants (55 novel) suspected to cause GT. Four large deletions or duplications were found by quantitative real-time PCR. Families with mutations in either gene were indistinguishable in terms of bleeding severity that varied even among siblings. Families were grouped into type I and the rarer type II or variant forms with residual αIIbβ3 expression. Variant forms helped identify genes encoding proteins mediating integrin activation. Splicing defects and stop codons were common for both ITGA2B and ITGB3 and essentially led to a reduced or absent αIIbβ3 expression; included was a heterozygous c.1440-13_c.1440-1del in intron 14 of ITGA2B causing exon skipping in 7 unrelated families. Molecular modeling revealed how many missense mutations induced subtle changes in αIIb and β3 domain structure across both subunits thereby interfering with integrin maturation and/or function. Our study extends knowledge of Glanzmann thrombasthenia and the pathophysiology of an integrin. This article is protected by copyright. All rights reserved.
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Δ(9)-tetrahydrocannabinol (Δ(9)-THC) is the major psychoactive cannabinoid in hemp (Cannabis sativa L.) and responsible for many of the pharmacological effects mediated via cannabinoid receptors. Despite being the major cannabinoid scaffold in nature, Δ(9)-THC double bond isomers remain poorly studied. The chemical scaffold of tetrahydrocannabinol can be assembled from the condensation of distinctly substituted phenols and monoterpenes. Here we explored a microwave-assisted one pot heterogeneous synthesis of Δ(3)-THC from orcinol (1a) and pulegone (2). Four Δ(3)-THC analogues and corresponding Δ(4a)-tetrahydroxanthenes (Δ(4a)-THXs) were synthesized regioselectively and showed differential binding affinities for CB1 and CB2 cannabinoid receptors. Here we report for the first time the CB1 receptor binding of Δ(3)-THC, revealing a more potent receptor binding affinity for the (S)-(-) isomer (hCB1Ki = 5 nM) compared to the (R)-(+) isomer (hCB1Ki = 29 nM). Like Δ(9)-THC, also Δ(3)-THC analogues are partial agonists at CB receptors as indicated by [(35)S]GTPγS binding assays. Interestingly, the THC structural isomers Δ(4a)-THXs showed selective binding and partial agonism at CB2 receptors, revealing a simple non-natural natural product-derived scaffold for novel CB2 ligands.
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BACKGROUND Receptor activator of NF-κB ligand (RANKL) is expressed as either surface (hRANKL1, hRANKL2) or soluble (hRANKL3) form. RANKL is involved in multifaceted processes of immunoregulation and bone resorption such as they occur in rheumatoid arthritis (RA). Interestingly, activated basophils, which are effector cells in allergic inflammation, contribute to the progress of collagen-induced arthritis (CIA), a mouse model for RA. Here, we investigate under which conditions human basophils express RANKL. METHODS Among other stimuli, basophils were cultured with IL-3 alone. Alternatively, as a secondary stimulus, IgER-dependent or IgER-independent agents were added simultaneously either with IL-3 or after prolonged IL-3 culturing. Expression of RANKL protein and mRNA was analyzed by flow cytometry, ELISA, and real-time PCR. A coculture system was applied to investigate biological activity of basophil-derived RANKL. RESULTS We show that in human basophils, IL-3 but no other stimulus induces de novo expression of soluble and surface RANKL, of which the latter enhances survival of MoDC. Upon simultaneous stimulation, IgER cross-linking reduces surface RANKL expression, while IgER-independent stimuli have no effect. This is in contrast to consecutive stimulation, as triggering with both IgER-dependent and IgER-independent stimuli enhances RANKL expression, particularly in its soluble form. Real-time PCR analysis shows that RANKL expression is mainly regulated at the mRNA level. CONCLUSION This study identifies IL-3 as a potent inducer of RANKL expression in human basophils, suggesting them to interact with bone physiology and activation of immune cells. IgER-dependent and IgER-independent stimuli modulate the IL-3-mediated RANKL expression in a time- and stimulus-dependent fashion.
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The majority of pemphigus vulgaris (PV) patients suffer from a live-threatening loss of intercellular adhesion between keratinocytes (acantholysis). The disease is caused by auto-antibodies that bind to desmosomal cadherins desmoglein (Dsg) 3 or Dsg3 and Dsg1 in mucous membranes and skin. A currently unresolved controversy in PV is whether apoptosis is involved in the pathogenic process. The objective of this study was to perform preclinical studies to investigate apoptotic pathway activation in PV pathogenesis with the goal to assess its potential for clinical therapy. For this purpose, we investigated mouse and human skin keratinocyte cultures treated with PV antibodies (the experimental Dsg3 monospecific antibody AK23 or PV patients IgG), PV mouse models (passive transfer of AK23 or PVIgG into adult and neonatal mice) as well as PV patients' biopsies (n=6). A combination of TUNEL assay, analyses of membrane integrity, early apoptotic markers such as cleaved poly-ADP-ribose polymerase (PARP) and the collapse of actin cytoskeleton failed to provide evidence for apoptosis in PV pathogenesis. However, the in vitro and in vivo PV models, allowing to monitor progression of lesion formation, revealed an early, transient and low-level caspase-3 activation. Pharmacological inhibition confirmed the functional implication of caspase-3 in major events in PV such as shedding of Dsg3, keratin retraction, proliferation including c-Myc induction, p38MAPK activation and acantholysis. Together, these data identify low-level caspase-3 activation downstream of disrupted Dsg3 trans- or cis-adhesion as a major event in PV pathogenesis that is non-synonymous with apoptosis and represents, unlike apoptotic components, a promising target for clinical therapy. At a broader level, these results posit that an impairment of adhesive functions in concert with low-level, non-lethal caspase-3 activation can evoke profound cellular changes which may be of relevance for other diseases including cancer.
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Abstract BACKGROUND: 3-Bromotyrosine (3-BrY) is a stable product of eosinophil peroxidase and may serve as a marker of eosinophil activation. A gas chromatography/mass spectrometry method to measure 3-BrY concentrations in serum from dogs has recently been established and analytically validated. The aims of this study were to determine the stability of 3-BrY in serum, to determine the association between peripheral eosinophil counts and the presence of an eosinophilic infiltrate in the gastrointestinal tract, and to compare serum 3-BrY concentrations in healthy dogs (n = 52) and dogs with eosinophilic gastroenteritis (EGE; n = 27), lymphocytic-plasmacytic enteritis (LPE; n = 25), exocrine pancreatic insufficiency (EPI; n = 26), or pancreatitis (n = 27). RESULTS: Serum 3-BrY concentrations were stable for up to 8, 30, and 180 days at 4°C, -20°C, and -80°C, respectively. There was no significant association between peripheral eosinophil count and the presence of eosinophils in the GI tissues (P = 0.1733). Serum 3-BrY concentrations were significantly higher in dogs with EGE (median [range] = 5.04 [≤0.63-26.26] μmol/L), LPE (median [range] = 3.60 [≤0.63-15.67] μmol/L), and pancreatitis (median [range] = 1.49 [≤0.63-4.46] μmol/L) than in healthy control dogs (median [range] = ≤0.63 [≤0.63-1.79] μmol/L; P < 0.0001), whereas concentrations in dogs with EPI (median [range] = 0.73 [≤0.63-4.59] μmol/L) were not different compared to healthy control dogs. CONCLUSIONS: The present study revealed that 3-BrY concentrations were stable in serum when refrigerated and frozen. No relationship between peripheral eosinophil count and the presence of eosinophils infiltration in the GI tissues was found in this study. In addition, serum 3-BrY concentrations were increased in dogs with EGE, but also in dogs with LPE and pancreatitis. Further studies are needed to determine whether measurement of 3-BrY concentrations in serum may be useful to assess patients with suspected or confirmed EGE or LPE.
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BACKGROUND Treatment of retinopathy of prematurity (ROP) stage 3 plus with bevacizumab is still very controversial. We report the outcome of 6 eyes of 4 premature infants with ROP stage 3 plus disease treated with ranibizumab monotherapy. METHODS Six eyes of 4 premature infants with threshold ROP 3 plus disease in zone II, were treated with one intravitreal injection of 0.03 ml ranibizumab. No prior laser or other intravitreal therapy was done. Fundus examination was performed prior to the intervention and at each follow-up visit. Changes in various mean vital parameters one week post intervention compared to one week pre-intervention were assessed. RESULTS The gestational age (GA) of patient 1, 2, 3, and 4 at birth was 24 5/7, 24 5/7, 24 4/7, and 26 1/7 weeks, respectively. The birth weight was 500 grams, 450 grams, 665 grams, and 745 grams, respectively. The GA at the date of treatment ranged from 34 3/7 to 38 6/7 weeks. In one infant, upper air way infection was observed 2 days post injection of the second eye. Three eyes required paracentesis to reduce the intraocular pressure after injection and to restore central artery perfusion. After six months, all eyes showed complete retinal vascularisation without any signs of disease recurrence. CONCLUSIONS Treatment of ROP 3 plus disease with intravitreal ranibizumab was effective in all cases and should be considered for treatment. One infant developed an upper air way infection suspicious for nasopharyngitis, which might be a possible side effect of ranibizumab. Another frequent complication was intraocular pressure rise after injection. More patients with longer follow-up duration are mandatory to confirm the safety and efficacy of this treatment. TRIAL REGISTRATION NUMBER NCT02164604 ; Date of registration: 13.06.2014.
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BACKGROUND: Hyperosmolar therapy, using either mannitol or hypertonic saline (HTS), is considered the treatment of choice for intracranial hypertension. However, hyperosmolar agents may impair coagulation and platelet function, limiting their use in patients at risk for hemorrhage. Despite this, studies evaluating the effects of mannitol compared to other hyperosmolar agents in dogs are largely lacking. The aim of this study was to compare the in vitro effects on global hemostasis and platelet function of 20 % mannitol and 3 % HTS on canine blood. METHODS: Citrated whole blood from 15 healthy dogs was diluted with 0.9 % saline, 20 % mannitol and 3 % HTS in ratios of 1:16 and 1:8. Rotational thromboelastometry (ROTEM) was used to assess clotting time (CT), clot formation time (CFT) and maximal clot firmness (MCF) following extrinsic activation (Ex-tem) and after platelet inhibition (Fib-tem). A platelet function analyzer (PFA-100) was used to assess closure time (CtPFA). RESULTS: No significant differences were observed between untreated whole blood and samples diluted with saline. Samples diluted with both mannitol and HTS were hypocoagulable compared to untreated whole blood samples. At a dilution of 1:16, no significant differences were found between any measured parameter in samples diluted with saline compared to mannitol or HTS. At a 1:8 dilution, CtPFA was prolonged in samples diluted with mannitol and HTS compared to saline, and CtPFA was prolonged more with mannitol than HTS. Ex-tem CT was increased at a 1:8 dilution with mannitol compared to HTS. Ex-tem CFT was prolonged at a 1:8 dilution with both agents compared to saline, and was prolonged more with mannitol than HTS. Ex-tem MCF was reduced at a 1:8 dilution with both agents compared to saline. DISCUSSION AND CONCLUSIONS: Data in this study indicate that both mannitol and HTS affect canine platelet function and whole blood coagulation in vitro in a dose-dependent fashion. The most pronounced effects were observed after high dilutions with mannitol, which impaired platelet aggregation, clot formation time, clot strength, and fibrin formation significantly more than HTS. Further in vivo studies are necessary before recommendations can be made
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INTRODUCTION The aim of this study was to evaluate the concordance of 2- and 3-dimensional radiography and histopathology in the diagnosis of periapical lesions. METHODS Patients were consecutively enrolled in this study provided that preoperative periapical radiography (PR) and cone-beam computed tomographic imaging of the tooth to be treated with apical surgery were performed. The periapical lesional tissue was histologically analyzed by 2 blinded examiners. The final histologic diagnosis was compared with the radiographic assessments of 4 blinded observers. The initial study material included 62 teeth in the same number of patients. RESULTS Four lesions had to be excluded during processing, resulting in a final number of 58 evaluated cases (31 women and 27 men, mean age = 55 years). The final histologic diagnosis of the periapical lesions included 55 granulomas (94.8%) and 3 cysts (5.2%). Histologic analysis of the tissue samples from the apical lesions exhibited an almost perfect agreement between the 2 experienced investigators with an overall agreement of 94.83% (kappa = 0.8011). Radiographic assessment overestimated cysts by 28.4% (cone-beam computed tomographic imaging) and 20.7% (periapical radiography), respectively. Comparing the correlation of the radiographic diagnosis of 4 observers with the final histologic diagnosis, 2-dimensional (kappa = 0.104) and 3-dimensional imaging (kappa = 0.111) provided only minimum agreement. CONCLUSIONS To establish a final diagnosis of an apical radiolucency, the tissue specimen should be evaluated histologically and specified as a granuloma (with/without epithelium) or a cyst. Analysis of 2-dimensional and 3-dimensional radiographic images alike results only in a tentative diagnosis that should be confirmed with biopsy.