Trichothecene mycotoxins activate NLRP3 inflammasome through a P2X7 receptor and Src tyrosine kinase dependent pathway

Inflammasome is an intracellular molecular platform of the innate immunity that is a key mediator of inflammation. The inflammasome complex detects pathogens and different danger signals, and triggers cysteine protease caspase-1-dependent processing of pro-inflammatory cytokines IL-1β, and IL-18 in dendritic cells and macrophages. Previously, we have shown that water-damaged building associated trichothecene mycotoxins, including roridin A, trigger IL-1β and IL-18 secretion in human macrophages. However, the molecular basis as well as mechanism behind this trichothecene-induced cytokine secretion has remained uncharacterized. Here, we show that the trichothecene-induced IL-1β secretion is dependent on NLRP3 inflammasome in human primary macrophages. Pharmacological inhibition and small interfering RNA approach showed that the trichothecene-induced NLRP3 inflammasome activation is mediated through ATP-gated P2X₇ receptor. Moreover, we show that trichothecene-triggered NLRP3 inflammasome activation is dependent on Src tyrosine kinase activity. In addition, gene silencing of c-Cbl, a negative autophagy-related regulator of c-Src, resulted in enhanced secretion of IL-1β and IL-18 in response to trichothecene mycotoxin stimulation in human macrophages. In conclusion, our results suggest that roridin A, a fungal trichothecene mycotoxin, acts as microbial danger signals that trigger activation of NLRP3 inflammasome through P2X₇R and Src tyrosine kinase signaling dependent pathway in human primary macrophages.     

Body composition changes by DXA, BIA and skinfolds during exercise training in women

Purpose

Few studies have examined responsiveness of bioimpedance (BIA) to detect changes over time in body composition using a longitudinal design. Accuracy of BIA and skinfold thickness in estimating body composition among 39–64 year-old women was investigated using dual-energy X-ray absorptiometry (DXA) as a criterion method both cross-sectionally and during a training intervention.

Methods

97 women had percentage of fat assessed using DXA, skinfolds and eight-polar BIA using multi-frequency current. Fat mass and lean mass were estimated by DXA and BIA. Measurements were performed before and after the 21-week training intervention.

Results

At baseline relative to DXA, BIA under predicted percentage of fat (?6.50 %) and fat mass (?3.42 kg) and overestimated lean mass (3.18 kg) considerably. Also skinfold measurement under predicted percentage of fat compared to DXA, but the difference was smaller (?1.69 % units). Skinfold measurement overestimated percentage of fat at low values and underestimated at high values (r ² = 0.535). A significant bias was detected between DXA and BIA’s estimate of change in percentage of fat, fat mass and lean mass. Compared to DXA, BIA and skinfolds underestimated the training-induced positive changes in body composition.

Conclusions

BIA and skinfold methods compared to DXA are not interchangeable to quantify the percentage of fat, fat mass and lean mass at the cross-sectional design in middle-aged women. Moreover, exercise training-induced small changes in body composition cannot be detected with BIA or skinfold method, even though DXA was able to measure statistically significant within-group changes in body composition after training.     

Transglutaminase-mediated cross-linking of a peptic fraction of omega-5 gliadin enhances IgE reactivity in wheat-dependent,exercise-induced anaphylaxis

BACKGROUND: Patients with wheat-dependent, exercise-induced anaphylaxis (WDEIA) experience recurrent anaphylactic reactions when exercising after ingestion of wheat products. We have identified omega-5 gliadin (Tri a 19) as a major allergen in WDEIA, but the role of exercise in eliciting the symptoms remains obscure. OBJECTIVE: The aim was to examine whether tissue transglutaminase (tTG)-mediated cross-linking could be involved in modulating the IgE-binding ability and in vivo reactivity of digested omega-5 gliadin peptides in WDEIA. METHODS: Purified omega-5 gliadin was digested with pepsin or with pepsin and trypsin and treated with tTG. The binding of IgE antibodies in pooled sera from 10 patients with WDEIA was studied by means of immunoblotting before and after tTG treatment of the digested peptides. The peptides derived from pepsin digestion were separated by means of gel-filtration chromatography, and IgE reactivity of 4 different peptide fractions was studied by immunoblotting before and after tTG treatment. The fraction showing the greatest degree of cross-linking by tTG was further studied by means of IgE ELISA, ELISA inhibition, and skin prick testing. RESULTS: The IgE-binding ability of omega-5 gliadin was retained after pepsin and pepsin-trypsin digestion. tTG treatment of the whole peptic digest formed large peptide complexes, with molecular weights ranging from 40 to greater than 200 kd. These cross-linked aggregates bound IgE antibodies in immunoblotting more intensely than untreated, pepsin-digested, or pepsin-trypsin-digested omega-5 gliadin. A gel-filtration fraction of the whole peptic digest corresponding to the highest peak of the chromatogram and showing the greatest degree of tTG-mediated cross-linking showed an increase in serum IgE reactivity in ELISA after tTG treatment, as well as a shift of reactivity to cross-linked complexes. In the 20 patients with WDEIA, the mean skin prick test wheal elicited by this tTG-treated peptic fraction was 77% larger (P <.001) than that elicited by the untreated peptic fraction and 56% larger (P <.01) than that elicited by intact omega-5 gliadin. CONCLUSIONS: Omega-5 gliadin-derived peptides are cross-linked by tTG, which causes a marked increase in IgE binding both in vitro and in vivo. Activation of tTG during exercise in the intestinal mucosa of patients with WDEIA could lead to the formation of large allergen complexes capable of eliciting anaphylactic reactions.     

Prognostic value of the combined assessment of proliferating cell nuclear antigen immunostaining and nuclear DNA content in invasive human mammary carcinomas

The expression of theS-phase associated, nuclear protein proliferating cell nuclear antigen (PCNA) was investigated in routinely paraffin-embedded surgical specimens from 209 breast cancer patients. Cytometric DNA assessments were performed on fine-needle aspirates, upon which the primary diagnosis of breast cancer had been based. The mean clinical follow-up was 16 years (range 13–20 years). The percentage of PCNA immunoreactive tumour cells ranged between less than 5 to 60% (mean value 13.34%). There was a direct association between PCNA expression, high histological tumour grade (p<0.01), and DNA aneuploidy (p=0.009). In a subgroup of 22 patients with near-diploid DNA distribution patterns the PCNA expression yielded additional prognostic information. Patients with tumours of near-diploid DNA histograms and more than 20% of PCNA immunoreactive neoplastic cells had a significantly worse clinical course, than patients with neardiploid tumours containing less than 20% PCNA immunoreactive cells (p=0.0001). In contrast, the PCNA immunoreactivity did not yield additional prognostic information for patients with distinctly diploid or highly aneuploid tumour variants. In a multivariate analysis comprising all 209 patients, nodal status (p<0.01), tumour size (p<0.01), and DNA ploidy (p<0.01) were found to have significant prognostic effect. The findings indicate that carcinomas characterised by high proliferative activity and near-diploid DNA distribution patterns can show rapid tumour progression. The combined assessment of the PCNA immunoreactivity and of the nuclear DNA content in routinely processed surgical specimens of breast cancer patients appears to be of prognostic value.     

Importance of the left auditory areas in chord discrimination in music experts as demonstrated by MEG

The brain basis behind musical competence in its various forms is not yet known. To determine the pattern of hemispheric lateralization during sound‐change discrimination, we recorded the magnetic counterpart of the electrical mismatch negativity (MMNm) responses in professional musicians, musical participants (with high scores in the musicality tests but without professional training in music) and non‐musicians. While watching a silenced video, they were presented with short sounds with frequency and duration deviants and C major chords with C minor chords as deviants. MMNm to chord deviants was stronger in both musicians and musical participants than in non‐musicians, particularly in their left hemisphere. No group differences were obtained in the MMNm strength in the right hemisphere in any of the conditions or in the left hemisphere in the case of frequency or duration deviants. Thus, in addition to professional training in music, musical aptitude (combined with lower‐level musical training) is also reflected in brain functioning related to sound discrimination. The present magnetoencephalographic evidence therefore indicates that the sound discrimination abilities may be differentially distributed in the brain in musically competent and naïve participants, especially in a musical context established by chord stimuli: the higher forms of musical competence engage both auditory cortices in an integrative manner.     

A follow‐up study on 6‐[18F]fluoro‐L‐dopa uptake in early Parkinson's disease shows nonlinear progression in the putamen

Sixteen subjects with de novo Parkinson's disease (PD) underwent three 6‐[18F]fluoro‐L‐dopa (Fdopa) positron emission tomography (PET) scans during a follow‐up time of 5 years (mean ± SD 5.5 ± 0.4 years) to study the progression of striatal dopaminergic hypofunction. Throughout the study, the smallest Fdopa uptake values were found in the dorso‐caudal part of the putamen contralateral to the side with dominant motor symptoms. The rate of decline in Fdopa uptake in the contralateral putamen was faster in the beginning of the disease and slowed down as the disease progressed. The annual decline in Fdopa influx constant (Ki, unit × 10^?3 min^?1) was on average 0.5 during the first 2 years and 0.2 during the subsequent 3 years (P = 0.002) in the contralateral putamen. In caudate, the rate of decline in Fdopa values was slower than in the putamen and did not change significantly during the follow‐up time, annual decline in the contralateral caudate being 0.1 between baseline and 2 years and 0.3 between 2 and 5 years (P = 0.4). These results suggest that progression of putaminal dopaminergic hypofuncion in PD follows a nonlinear pattern at least in the contralateral side being faster in the beginning of the disease. © 2009 Movement Disorder Society     

Treatment of intracranial atherosclerotic arterial stenoses with a balloon-expandable cobalt chromium stent (Coroflex Blue): procedural safety, efficacy, and midterm patency

Introduction

We evaluated the coronary balloon-expandable cobalt chromium stent Coroflex Blue for the treatment of intracranial atherosclerotic arterial stenoses (IAAS).

Methods

Between March 2007 and October 2007, a total of 25 patients (20 male, age median 67 years) with 30 IAAS underwent endovascular treatment using Coroflex Blue stents (B. Braun, Germany). Location and degree of target stenoses before and after treatment and at follow-up and adverse clinical sequelae of treatment were registered. Angiographic follow-up was scheduled for 6, 12, 26, and 52 weeks after the treatment.

Results

The 30 treated lesions were located as follows: nine in intracranial–extradural internal carotid artery (ICA), three in intradural ICA, five in middle cerebral artery, eight in intradural vertebral artery, and five in basilar artery. The technical success rate was 100%. The degree of stenoses prior to and after treatment was 61?±?2% and 26?±?3% (mean ± SE), respectively. A residual stenosis of <50% was achieved in 29 (97%) procedures. Treatment was uneventful in 28 out of 30 procedures (93%); one patient suffered a transient and one patient a permanent neurological deficit. Angiographic follow-up was available in all of the patients (100%) after 15.2 months (median) and showed significant (i.e., more than 50%) degree of recurrent stenosis in 11 (37%) of the lesions. Retreatment was performed in 11 (37%) lesions.

Conclusion

The Coroflex Blue stent is easily inserted and safely deployed into intracranial arteries. The incidence of recurrent stenoses remains a concern. Stringent angiographic and clinical follow-up and retreatment are therefore mandatory.     

Endovascular coil occlusion of 1811 intracranial aneurysms: early angiographic and clinical results

OBJECTIVE: We sought to evaluate the early angiographic and clinical outcomes of the first session of endovascular coil occlusion of a large number of patients with intracranial aneurysms treated by five neurointerventionalists during a decade at a single center. METHODS: We performed retrospective analyses of pre- and postprocedural angiographic studies and early clinical outcomes. Enrolled patients underwent endovascular treatment of intracranial aneurysms with detachable coils. RESULTS: A total of 1811 aneurysms in 1579 patients were treated with coil occlusion. Of these, 90 to 100% occlusion of 86.5% of the aneurysms was achieved. In 82.3% of the procedures, no complications occurred. The clinical outcome profile at primary discharge according to the Glasgow Outcome Scale was as follows: Grade V, 74.6%; Grade IV, 6.7%; Grade III, 11.1%; Grade II, 3.1%; and Grade I, 4.5%. In patients with large aneurysms with wide necks, a lower occlusion rate and an increased complication rate were encountered. The use of three-dimensional and fibered coils resulted in higher occlusion rates. Balloon remodeling and stent deployment increased the complication rate. Previous aneurysm rupture, procedural complications, and vasospasm correlated with poor outcome. Of the patients in poor grade after aneurysm rupture, 42% recovered to Glasgow Outcome Scale Grade IV or V, as opposed to 90% of patients who were treated for unruptured aneurysms. The ischemic complication rate was 9%, and the hemorrhagic complication rate was 3%. The early procedural morbidity rate was 5.3%, and the procedural mortality rate was 1.5%. The management mortality rate was 4.4%. CONCLUSION: These data confirm the safety and efficacy of endovascular coil occlusion for patients with intracranial aneurysms.     

Long‐term follow‐up of two siblings with adult‐onset neuronal ceroid lipofuscinosis,Kufs type A

Aim. Reports on the clinical presentation of adult‐onset neuronal ceroid lipofuscinoses (NCL) are scarce compared to infantile‐ and childhood‐onset forms. Here, we aimed to present detailed temporal evolution of clinical and electrophysiological features of two siblings with adult‐onset NCL and homozygous mutation in the CLN6 gene. Methods. We retrospectively analysed medical records and electrophysiological data in order to delineate evolution of clinical and electrophysiological findings. Electrophysiological studies included routine EEG and video‐EEG, as well as polymyographic analysis of myoclonus and brainstem reflex studies. Results. Both patients had seizures and cerebellar signs. Despite the slow progression of ataxia, they developed no mental deterioration, but had severe obsessive compulsive disorder and depression. EEG revealed frequent generalized spikes, polyspikes, and waves, prominent on awakening and during photic stimulation without significant change throughout the clinical course. Abnormalities concerning the blink reflex, auditory startle response, and startle response to somatosensory inputs manifested within four years. The patients underwent transient and mild improvement with valproate, whereas ataxia and seizures were dramatically ameliorated following high‐dose piracetam. Conclusions. Patients with adult‐onset NCL may present with slowly progressive ataxia, persistent photosensitivity, and seizures without dementia or extrapyramidal findings. Brainstem abnormalities become more evident with time, in line with ataxia. Piracetam is effective for both seizures and ataxia.