T cell immune response predicts survival in severely ill COVID-19 patients requiring venovenous extracorporeal membrane oxygenation support.

Introduction: There is a critical gap in understanding which SARS-CoV-2 patients would benefit most from venovenous extracorporeal membrane oxygenation (VV-ECMO) support. The potential role of a dysregulated immune response is still unclear in this patient population. Objectives: To assess the potential predictive value of SARS-CoV-2 specific cellular and humoral immune responses for survival in critically ill COVID-19 patients requiring VV-ECMO. Methods: We conducted a prospective single-center observational study of unvaccinated patients requiring VV-ECMO support treated at the intensive care unit of Semmelweis University Heart and Vascular Center between March and December 2021. Peripheral blood samples were collected to measure the humoral and cellular immune statuses of the patients at the VV-ECMO cannulation. Patients were followed until hospital discharge. Results: Overall, 35 COVID-19 patients (63% men, median age 37 years) on VV-ECMO support were included in our study. The time from COVID-19 verification to ECMO support was a median (IQR) of 10 (7-14) days. Of the patients, 9 (26%) were discharged alive and 26 (74%) died during their hospital stay. Immune tests confirmed ongoing SARS-CoV-2 infection in all the patients, showing an increased humoral immune response. SARS-CoV-2-specific cellular immune response was significantly higher among survivors compared to the deceased patients. A higher probability of survival was observed in patients with markers indicating a higher T cell response detected by both QuantiFeron (QF) and flow cytometry (Flow) assays. (Flow S1 CD8+ ≥ 0.15%, Flow S1 CD4+ ≥ 0.02%, QF CD4 ≥ 0.07, QF whole genome ≥ 0.59). In univariate Cox proportional hazard regression analysis BMI, right ventricular (RV) failure, QF whole genome T cell level, and Flow S1 CD8+ T cell level were associated with mortality, and we found that an increased T cell response showed a significant negative association with mortality, independent of BMI and RV failure. Conclusion: Evaluation of SARS-CoV-2 specific T cell response before the cannulation can aid the risk stratification and evaluation of seriously ill COVID-19 patients undergoing VV-ECMO support by predicting survival, potentially changing our clinical practice in the future.

Thyroid disturbances after COVID-19 and the effect of vaccination in children: a prospective tri-center registry analysis.

Rapidly evolving clinical data suggest that the novel coronavirus (SARS-CoV-2) and vaccination against COVID-19 might be associated with thyroid disturbances. However, studies remain limited among the pediatric population. Our aim was to assess the prevalence and permanence of thyroid autoimmunity (TA) and dysfunction in children after an acute infection and its potential association with vaccination. A prospective, multicenter registry analysis was performed among 458 children (mean age: 12.4 ± 3,8 years, 45.4% male) with preceding COVID-19. Patient inclusion lasted from 24th March, 2021 to 23rd March, 2022 at three pediatric outpatient facilities at Semmelweis University, Budapest. Primary outcomes were the rate of thyroid disturbances assessed by laboratory parameters (thyroid function tests, antithyroglobulin [ATG] and anti-thyroid peroxidase [ATPO] antibodies) and thyroid ultrasound. TA rate among vaccinated and unvaccinated children was determined. Children with newly diagnosed thyroid alterations were followed up for 12.7 ± 4.3 months. Six children had previous thyroid disease. Out of 452 children, 30 cases (6.6%) of newly diagnosed TA (six of them had abnormal thyroid-stimulating hormone [TSH] levels) and eight cases (1.8%) of isolated TSH elevation were observed. Ultrasound-proven autoimmune thyroiditis (AIT) was 4.0%. No association was found between COVID-19 vaccination and thyroid autoimmunity (χ2(1,N = 452) = 0.138, p = 0.815). Among children with TA, 73.3% had long-lasting alterations.  Conclusion: Vaccination had no effect on the prevalence of TA. Until further controlled studies state otherwise, children with preceding COVID-19 might benefit from thyroid screening. What is Known: • Numerous case reports implicate that coronavirus disease-2019 (COVID-19) and vaccination against SARS-CoV-2 can be responsible for thyroid disturbances. • Thyroid alterations discovered during acute COVID-19 tend to cease by time and only incidental thyroid autoimmunity (TA) is diagnosed after COVID-19. In adults, no increase in vaccine-related hyper- or hypothyroidism was found. What is New: • TA rate after COVID-19 vaccination among children was not increased. TA had no role in long COVID syndrome. • We discovered a considerable rate of TA (6.6%) and ultrasound-proven autoimmune thyroiditis (AIT) (4.0%) after SARS-CoV-2 infection, and the majority of these alterations remained positive after 6 months.

Factors influencing the SARS-CoV-2 infection and vaccination induced immune response in rheumatoid arthritis.

Background: To investigate the factors that have significant impact on the Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) infection and vaccination induced immune response in rheumatoid arthritis (RA). Methods: Serological response was measured by quantifying anti-SARS-CoV-2 specific antibodies, while the cell-mediated response was measured by a whole-blood test quantifying the interferon (IFN)-γ response to different SARS-CoV-2-specific domains. Results: We prospectively enrolled 109 RA patients and 43 healthy controls. The median time (IQR) between the confirmed infection or the last vaccination dose and the day when samples were taken ("sampling interval") was 3.67 (2.03, 5.50) months in the RA group. Anti-Spike (anti-S) specific antibodies were detected in 94% of RA patients. Among the investigated patient related variables, age (p<0.004), sampling interval (p<0.001), the brand of the vaccine (p<0.001) and targeted RA therapy (TNF-inhibitor, IL-6 inhibitor, anti-CD20 therapy) had significant effect on the anti-S levels. After covariate adjustment TNF-inhibitor therapy decreased the anti-S antibody concentrations by 80% (p<0.001). The same figures for IL-6 inhibitor and anti-CD20 therapy were 74% (p=0.049) and 97% (p=0.002), respectively. Compared to subjects who were infected but were not vaccinated, the RNA COVID-19 vaccines increased the anti-S antibody levels to 71.1 (mRNA-1273) and 36.0 (BNT162b2) fold (p<0.001). The corresponding figure for the ChAdOx1s vaccine is 18.1(p=0.037). Anti-CCP (anti-cyclic citrullinated peptides) positive patients had 6.28 times (p= 0.00165) higher anti-S levels, than the anti-CCP negative patients. Positive T-cell response was observed in 87% of the healthy volunteer group and in 52% of the RA patient group. Following vaccination or infection it declined significantly (p= 0.044) but more slowly than that of anti-S titer (6%/month versus 25%). Specific T-cell responses were decreased by 65% in patients treated with anti-CD20 therapy (p=0.055). Conclusion: Our study showed that the SARS-CoV-2-specific antibody levels were substantially reduced in RA patients treated with TNF-α-inhibitors (N=51) and IL-6-inhibitor (N=15). In addition, anti-CD20 therapy (N=4) inhibited both SARS-CoV-2-induced humoral and cellular immune responses. Furthermore, the magnitude of humoral and cellular immune response was dependent on the age and decreased over time. The RNA vaccines and ChAdOx1s vaccine effectively increased the level of anti-S antibodies.

Immunological response and temporal associations in myocarditis after COVID-19 vaccination using cardiac magnetic resonance imaging: An amplified T-cell response at the heart of it?

Introduction: Although myocarditis after anti-SARS-CoV-2 vaccination is increasingly recognized, we have little data regarding the course of the disease and, consequently, the imaging findings, including the tissue-specific features. The purpose of this study is to describe the clinical, immunological, and cardiac magnetic resonance (CMR) features of myocarditis after COVID-19 immunization in the acute phase and during follow-up. We aimed to compare the trajectory of the disease to myocarditis cases unrelated to COVID-19. Methods: We assembled a CMR-based registry of potentially COVID-19 vaccination-related myocarditis cases. All patients who experienced new-onset chest pain and troponin elevation after COVID-19 vaccination and imaging confirming the clinical suspicion of acute myocarditis were enrolled in our study. Participants underwent routine laboratory testing and testing of their humoral and cellular immune response to COVID-19 vaccination. Clinical and CMR follow-up was performed after 3-6 months. We included two separate, sex- and age-matched control groups: (1) individuals with myocarditis unrelated to COVID-19 infection or vaccination confirmed by CMR and (2) volunteers with similar immunological exposure to SARS-CoV-2 compared to our group of interest (no difference in the number of doses, types and the time since anti-SARS-CoV-2 vaccination and no difference in anti-nucleocapsid levels). Results: We report 16 CMR-confirmed cases of myocarditis presenting (mean ± SD) 4 ± 2 days after administration of the anti-SARS-CoV-2 vaccine (male patients, 22 ± 7 years), frequently with predisposing factors such as immune-mediated disease and previous myocarditis. We found that 75% received mRNA vaccines, and 25% received vector vaccines. During follow-up, CMR metrics depicting myocardial injury, including oedema and necrosis, decreased or completely disappeared. There was no difference regarding the CMR metrics between myocarditis after immunization and myocarditis unrelated to COVID-19. We found an increased T-cell response among myocarditis patients compared to matched controls (p < 0.01), while there was no difference in the humoral immune response. Conclusion: In our cohort, myocarditis occurred after both mRNA and vector anti-SARS-CoV-2 vaccination, frequently in individuals with predisposing factors. Upon follow-up, the myocardial injury had healed. Notably, an amplified cellular immune response was found in acute myocarditis cases occurring 4 days after COVID-19 vaccination.

Seroconversion after anti-SARS-CoV-2 mRNA vaccinations among moderate-to-severe psoriatic patients receiving systemic biologicals-Prospective observational cohort study.

It is unclear whether biological antipsoriatic therapies affect seroconversion after messenger ribonucleic acid (mRNA)-based antisevere acute respiratory syndrome coronavirus 2 (anti-SARS-CoV-2) vaccinations. To assess antibody formation and the incidence of side effects after anti-SARS-CoV-2 mRNA vaccinations in psoriatic patients receiving different biologicals compared to healthy controls. 102 moderate-to-severe psoriatic patients (56.2 [±13.5] years) and 55 age-matched healthy (56.4 ± 13.6 years) volunteers were included in our study. Ten to 21 days after the administration of the second dosage of BNT162b2 or mRNA-1273 vaccine, antibody levels specific to the SARS-CoV-2 spike (S) protein receptor binding domain were monitored. The incidence of postvaccination side effects was recorded and compared to real-life data in the literature. Of the 102 patients, 57 (55.88%) received tumor necrosis factor (TNF), 28 (27.45%) received interleukin (IL)-12/23, 16 (15.68%) received IL-17, and 1 (0.99%) received IL-23 inhibitors. No significant differences in the median serum level of anti-SARS-CoV-2S antibody were observed between the study population and the control group (median IQR range: 1681.0 U/mL (600.0-4844.0) versus 1984.0 U/mL (1000.0-3136.0; p = 0.82). The most frequent side effects of the mRNA vaccines within 7 days after the administration of both dosages were arm pain on the side of injection (23.53% and 23.53%), fatigue (9.80% and 13.72%), headache (4.9% and 5.88%), and chills or shivering (4.9% and 8.82%). Detectable antibodies against SARS-CoV-2S protein appear 10-21 days after the administration of the second dosage of BNT162b2 or mRNA-1273 vaccines in moderate-to-severe psoriatic patients receiving biologicals, similar to those of healthy controls.

Diagnosis and treatment of paediatric multisystem inflammatory syndrome / A gyermekkori koronavírus-fertozést követo sokszervi gyulladás diagnosztikája és kezelése.

Összefoglaló. A SARS-CoV-2-fertozés ritka gyermekkori szövodménye a sokszervi gyulladás, angol terminológiával paediatric inflammatory multisystem syndrome (PIMS). Két vagy több szerv érintettségével járó, súlyos tünetekkel induló betegségrol van szó, amelynek tünetei átfedést mutatnak a Kawasaki-betegséggel, a toxikus sokk szindrómával és a makrofágaktivációs szindrómával. A PIMS-betegek intenzív terápiás osztályon vagy intenzív terápiás háttérrel rendelkezo intézményben kezelendok, ahol biztosítottak a kardiológiai ellátás feltételei is. A szükséges immunterápia a klinikai prezentációtól függ. A jelen közleményben a szerzok a releváns nemzetközi irodalom áttekintését követoen ajánlást tesznek a PIMS diagnosztikai és terápiás algoritmusára. Orv Hetil. 2021; 162(17): 652-667. Summary. Pediatric inflammatory multisystem syndrome (PIMS) is a rare complication of SARS-CoV-2 infection in children. PIMS is a severe condition, involving two or more organ systems. The symptoms overlap with Kawasaki disease, toxic shock syndrome and macrophage activation syndrome. PIMS patients should be treated in an intensive care unit or in an institution with an intensive care background, where cardiological care is also provided. The required specific immunotherapy depends on the clinical presentation. In this paper, after reviewing the relevant international literature, the authors make a recommendation for the diagnostic and therapeutic algorithm for PIMS. Orv Hetil. 2021; 162(17): 652-667.

Comparison of virus neutralization activity and results of 10 different anti-SARS-CoV-2 serological tests in COVID-19 recovered plasma donors.

Serological testing is a tool to predict protection against later infection. This potential heavily relies on antibody levels showing acceptable agreement with gold standard virus neutralization tests. The aim of our study was to investigate diagnostic value of the available serological tests in terms of predicting virus neutralizing activity of serum samples drawn 5-7 weeks after onset of symptoms from 101 donors with a history of COVID-19. Immune responses against Receptor Binding Domain (RBD), Spike1 and 2 proteins and Nucleocapsid antigens were measured by various ELISA tests. Neutralizing antibody activity in serum samples was assessed by a cell-based virus neutralization test. Spearman correlation coefficients between serological and neutralization results ranged from 0.41 to 0.91 indicating moderate to strong correlation between ELISA test results and virus neutralization. The sensitivity and specificity of ELISA tests in the prediction of neutralization were 35-100% and 35-90% respectively. No clear cut off levels can be established that would reliably indicate neutralization activity. For some tests, however, a value below which the sample is not expected to neutralize can be established. Our data suggests that several of the ELISA kits tested may be suitable for epidemiological surveys 1-2 months after the infection, estimating whether a person may have recently exposed to the virus. Sensitivities considerably superseding specificity at the cut-off values proposed by the manufacturers suggest greater potential in the identification of insufficient antibody responses than in confirming protection. Nevertheless, the former might be important in assessing response to vaccination and characterizing therapeutic plasma preparations.

Relationship between leukocyte counts and large vessel occlusion in acute ischemic stroke.

BACKGROUND: Neuroinflammation plays an important role in the pathogenesis of acute ischemic stroke (AIS) and peripheral leukocyte counts have proved to be independent predictors of stroke severity and outcomes. Clinical significance of large vessel occlusion (LVO) in AIS is increasing, as these patients are potential candidates for endovascular thrombectomy and likely to have worse outcomes if not treated urgently. The aim of our study was to assess the relationship between on admission leukocyte counts and the presence of LVO in the early phase of AIS. METHODS: We have conducted a cross-sectional, observational study based on a registry of consecutive AIS patients admitted up to 4.5 h after stroke onset. Blood samples were taken at admission and leukocyte counts were measured immediately. The presence of LVO was verified based on the computed tomography angiography scan on admission. RESULTS: Total white blood cell (WBC) and neutrophil counts were significantly higher in patients with LVO than those without LVO (P < 0.001 respectively). After adjustment for potential confounders total WBC counts (adjusted OR: 1.405 per 1 × 109/L increase, 95% CI: 1.209 to 1.632) and neutrophil counts (adjusted OR: 1.344 per 1 × 109/L increase, 95% CI: 1.155 to 1.564) were found to have the strongest associations with the presence of LVO. Total WBC and neutrophil counts had moderate ability to discriminate an LVO in AIS (AUC: 0.667 and 0.655 respectively). No differences were recorded in leukocyte counts according to the size of the occluded vessel and the status of collateral circulation in the anterior vascular territory. However, total WBC and neutrophil counts tended to be higher in patients with LVO in the posterior circulation (p = 0.005 and 0.010 respectively). CONCLUSION: Higher admission total WBC and neutrophil counts are strongly associated with the presence of LVO and has moderate ability to discriminate an LVO in AIS. Detailed evaluation of stroke-evoked inflammatory mechanisms and changes according to the presence of LVO demands further investigation.

Use of JAR-Based Analysis for Improvement of Product Acceptance: A Case Study on Flavored Kefirs.

A common question of dairy product developments is the possible success of the new product. Several publications reported successful results using just-about-right (JAR) scales; although there is some debate about their advantages/disadvantages. This study highlights the limitations and opportunities of JAR scales and penalty analysis of fruit flavored kefirs. The first question is whether penalty analysis results help to improve the product and thus its overall liking (OAL)? The second question is what happens to those who rated the products "ideal" (JAR) before product development when evaluating the new products? Fruit flavored live-flora stirred-type kefir samples were formulated and evaluated by 92 consumers before and after the JAR-based product development. The OAL of two products significantly increased after product development. A new visualization tool is introduced, which shows what happens to those who rated the attribute as JAR but the attribute has been modified. A general product development scheme is also introduced for JAR-based kefir product development.

The relationship between hemorheological parameters and mortality in critically ill patients with and without sepsis.

PURPOSE: The prognostic scoring systems for mortality of intensive care patients estimate clinical outcome using several physiological and biochemical parameters. In altered hemodynamic conditions of critically ill patients, hemorheological variables may play a significant role in appropriate tissue perfusion. We investigated if hemorheological parameters are altered in critical status and if they could be markers of mortality. METHODS: 112 patients (67.8 ± 12 years, 58 males, 54 females) treated in intensive care unit with different non-surgical diseases were investigated. Routine laboratory parameters and prognostic scores were determined and hemorheological variables (hematocrit, plasma and whole blood viscosity, red blood cell aggregation and deformability) were measured on the 1st and the 2nd day after admission. RESULTS: ICU scores predicted 35.2-41.3% mortality rate, real mortality in intensive care unit was 37.5%, while 30-day mortality was 46.6%. Whole blood viscosity (WBV) and red blood cell (RBC) deformability were lower, red blood cell aggregation was higher in septic than in nonseptic patients (p < 0.05). In septic patients calcium was increased, osmolality was decreased, while in nonseptic patients WBV and RBC aggregation were higher in nonsurvivors compared to survivors (p < 0.05). Worsening of RBC deformability from day 1 to day 2 predicted higher mortality (p < 0.05). CONCLUSION: Calcium and osmolality level were associated with outcome in sepsis. Whole blood viscosity, red blood cell aggregation and change in red blood cell deformability could predict mortality in nonseptic patients and they may add prognostic information over the ICU scores. Further investigations are needed to evaluate the benefit of our findings in clinical practice.

Physical and psychological benefits of once-a-week Pilates exercises in young sedentary women: A 10-week longitudinal study.

Pilates exercises have several demonstrated physical and psychological benefits. To date, most research in this context was conducted with symptomatic or elderly people with few dependent measures. The current study examined the chronic or longitudinal effects of very low frequency, once a week, Pilates training on several physical and psychological measures, over a 10-week intervention, in young, healthy, and sedentary women. Further, the study gauged the acute effects of Pilates exercises on positive- and negative affect in 10 exercise sessions. Compared to a control group, the Pilates group exhibited significant improvements in skeletal muscle mass, flexibility, balance, core- and abdominal muscle strength, body awareness, and negative affect. This group also showed favorable changes in positive (22.5% increase) and negative affect (12.2% decrease) in nine out of ten exercise sessions. This work clearly demonstrates the acute and chronic benefits of Pilates training on both physical and psychological measures. It also reveals that even only once a week Pilates training is enough to trigger detectable benefits in young sedentary women. While this frequency is below the required levels of exercise for health, it may overcome the 'lack of time' excuse for not exercising and subsequently its tangible benefits may positively influence one's engagement in more physical activity.

Association of celiac disease and hereditary angioedema due to C1-inhibitor deficiency. Screening patients with hereditary angioedema for celiac disease: is it worth the effort?

OBJECTIVE: Hereditary angioedema due to C1-inhibitor deficiency is a life-threatening condition, which manifests as edematous attacks involving subcutaneous tissues and/or the upper airway/gastrointestinal mucosa. Celiac disease is a gluten-sensitive small intestinal disorder that can lead to severe villous atrophy, malabsorption, and malignancy. Both hereditary angioedema and celiac disease may present with abdominal symptoms. Our aim was to study the occurrence of celiac disease in the hereditary angioedema population, as well as to analyze the clinical course of cases with both diseases. METHODS: One hundred and twenty-eight patients with hereditary angioedema were screened for celiac disease, using serological methods [antiendomysial antibodies-immunoglobulin A (IgA), antiendomysial antibodies-IgG and tissue transglutaminase-IgA, tissue transglutaminase-IgG]. Clinical data of a child with hereditary angioedema and celiac disease diagnosed earlier were added to the dataset to be analyzed. Thus, the total number of patients was 129, comprising 107 adults and 22 pediatric patients. In patients with celiac disease, molecular genetics analysis (human leukocyte antigen-DQA1, human leukocyte antigen-DQB1) was carried out along with the introduction of a gluten-free diet and regular follow-up. RESULTS: Four out of the 22 children were diagnosed with celiac disease in our hereditary angioedema population. The prevalence of celiac disease among our pediatric patients with hereditary angioedema (22 children) was higher than in the general population (18.1 vs. 1.2%). Switching from the wheat starch-containing tranexamic acid product to danazol and introducing a gluten-free diet mitigated abdominal symptoms of hereditary angioedema. CONCLUSION: Similarities between the symptoms of hereditary angioedema and celiac disease may cause difficulties in differential diagnosis, as well as in choosing the appropriate therapy. In our opinion, screening hereditary angioedema patients for celiac disease is warranted if abdominal attacks or neurological symptoms persist despite adequate management. Complement testing is recommended whenever abdominal symptoms persist despite the histological and serological remission of gluten-sensitive enteropathy after the introduction of a gluten-free diet.

Voluntary exercise may engage proteasome function to benefit the brain after trauma.

Brain trauma is associated with long-term decrements in synaptic plasticity and cognitive function, which likely reside on the acute effects of the injury on protein structure and function. Based on the action of proteasome on protein synthesis and degradation we have examined the effects of brain injury on proteasome level/activity and the potential of exercise to interact with the effects of the injury. Exercise has a healing ability but its action on proteasome function is not understood. Male Sprague-Dawley adult rats (n=19) were performed mild brain fluid percussion injury (FPI) prior to exercise. Animals were assigned to four groups: sedentary (Sed) or exercise (Exc) with sham surgery (Sham) or FPI: Sham/Sed, Sham/Exc, FPI/Sed, FPI/Exc. Animals were sacrificed after 14 days of treatment. FPI elevated levels of carbonyl (160.1+/-9.6% SEM, p<0.01) and reduced synapsin I levels (58.3+/-4.3% SEM, p<0.01) in the ipsilateral side of caudal cerebral cortex (FPI/Sed compared to Sham/Sed controls), and it appears that increased levels of carbonyls were associated with increased chymotripsin like activity. These results seem to indicate that proteasome function may be associated with levels of oxidative stress, and that these events may contribute to the action of exercise on synaptic plasticity. Interestingly, exercise attenuated changes in carbonyls, proteasome activity, and synapsin I following FPI, which may indicate an action of exercise on the molecular substrates that control protein turnover following brain trauma. Levels of the regulatory transcription factor of proteasome, Zif 268 were reduced by exercise in Sham and FPI animals and changed in proportion with proteasome activity/content. The overall results indicate that the action of exercise interfaces with that of brain injury on molecular systems involved with protein fate and function, which may be significant for synaptic plasticity.

Exercise alters SIRT1, SIRT6, NAD and NAMPT levels in skeletal muscle of aged rats.

Silent information regulators are potent NAD(+)-dependent protein deacetylases, which have been shown to regulate gene silencing, muscle differentiation and DNA damage repair. Here, changes in the level and activity of sirtuin 1 (SIRT1) in response to exercise in groups of young and old rats were studied. There was an age-related increase in SIRT1 level, while exercise training significantly increased the relative activity of SIRT1. A strong inverse correlation was found between the nuclear activity of SIRT1 and the level of acetylated proteins. Exercise training induced SIRT1 activity due to the positive effect of exercise on the activity of nicotinamide phosphoribosyltransferase (NAMPT) and thereby the production of sirtuin-fueling NAD(+). Exercise training normalized the age-associated shift in redox balance, since exercised animals had significantly lower levels of carbonylated proteins, expression of hypoxia-inducible factor-1 alpha and vascular endothelial growth factor. The age-associated increase in the level of SIRT6 was attenuated by exercise training. On the other hand, aging did not significantly increase the level of DNA damage, which was in line with the activity of 8-oxoguanine DNA glycosylase, while exercise training increased the level of this enzyme. Regular exercise decelerates the deleterious effects of the aging process via SIRT1-dependent pathways through the stimulation of NAD(+) biosynthesis by NAMPT.

Serum beta2-microglobulin measured by immunonephelometry: expression patterns and reference intervals in healthy adults.

BACKGROUND: Serum beta2-microglobulin (beta2m) has been established as a marker of disease activity in malignancies, autoimmune conditions and infections. Despite its important role in prognosis assessment and disease monitoring, relatively few studies are available on its expression in healthy individuals. Furthermore, interpretation of results is hampered by the variety in reference limits due to differences in methodology, sample population and statistics. METHODS: Serum beta2m concentrations were measured using a microparticle-enhanced immunonephelometric method in 183 healthy blood donors aged 29-75 years. RESULTS: The median beta2m concentration was 1.67 (0.88-2.75) mg/L with no difference between men and women (1.71 mg/L vs. 1.62 mg/L, p<0.07). A linear correlation was found between beta2m and age (p<0.0001), serum concentrations significantly higher in older subjects (1.55, 1.59, 1.70, and 1.87 mg/L in age groups of 29-40, 40-50, 50-60 and 60-75 years, respectively, p<0.0001). Reference intervals obtained by non-parametric estimation after partitioning by age were 1.02-2.46 mg/L vs. 1.29-2.70 mg/L in younger (29-49 years) vs. older (50-75 years) individuals. CONCLUSIONS: These data can help standardise beta2m reference limits and support age-adjusted comparisons in clinical studies.

Interaction of photosensitizers with liposomes containing unsaturated lipid.

Small unilamellar liposomes were made of dipalmitoyl-phosphatidylcholine and dioleoyl-phosphatidylcholine, and photosensitized by a symmetrically or an asymmetrically substituted glycosilated tetraphenyl-porphyrin derivative. As differential scanning calorimetry and electron paramagnetic resonance spectroscopy (EPR) revealed these porphyrin derivatives were localized in different depth within the lipid bilayer. Both porphyrin derivatives were able to induce photoreaction and consequent structural changes in the membrane. 5-, 12-, or 16-doxyl stearic acid labeled lipid bilayers were applied and the efficiency of photoinduced reaction was followed by the decay of their EPR signal amplitude. Light dose-dependent destruction of nitroxide radical proved to be dependent on the position of spin label. In this process the porphyrin localized in closer connection with the double bond of unsaturated fatty acid was more effective. EPR signal decay was also dependent on the unsaturated fatty acid content of the liposome and the oxygen saturation of the solvent.

The effects of training and detraining on memory, neurotrophins and oxidative stress markers in rat brain.

In the current investigation we tested how swimming training (T) (8 week, 5 times/week, 2 h/day), and detraining (DT) affects brain functions and oxidative stress markers in rat brain. The free radical concentration, measured by electron paramagnetic resonance, decreased in brain of T and DT rats compared to controls (C). The level of brain-derived neurotrophic factor (BDNF) increased as a result of training, but decreased below the control level after 6 weeks of detraining. In addition, the concentration of nerve growth factor (NGF) also declined with DT. The passive avoidance test was used to assess the memory of rats, and training-induced improvement was observed but the enhancement disappeared with detraining. When the content of mitochondrial electron transport complexes, as a potent free radical generator, was evaluated by the blue native gel method, no significant alterations were observed. The repair of nuclear and mitochondrial 8-oxodeoxyguanosine, as measured by the activity of OGG1, showed no significant difference. Therefore, the results suggest that regular exercise training improves memory, decreases the level of reactive oxygen species, and increase the production of BDNF and NGF. On the other hand, it appears that the beneficial effects of training are reversible in the brain, since detraining down-regulates the neurotrophin level, and memory. It is suggested that exercise training is more likely to beneficially effect the production of reactive oxygen species and the related oxidative damage.

Interaction of tetraphenyl-porphyrin derivatives with DPPC-liposomes: an EPR study.

The effect of the symmetry and polarity of the porphyrin molecules on their membrane localization and interaction with membrane lipids were investigated by electron paramagnetic resonance (EPR). For this purpose, two glycoconjugated tetraphenyl porphyrin derivatives were selected, respectively, symmetrically and asymmetrically substituted. Small unilamellar liposomes composed of dipalmitoylphosphatidylcholine (DPPC) and spin labeled stearic acids were prepared. The spin probe was located at the 5th or 7th or 12th or 16th position of the hydrocarbon chain in order to monitor various regions of the lipid bilayer. EPR spectra of porphyrin-free and porphyrin-bound liposomes were recorded at various temperatures below and above the phase transition temperature of DPPC. The effect on membrane fluidity proved to be stronger with the asymmetrical porphyrin derivative than with the symmetrical one. The rigidity increased when the spin label was near lipid head groups. The difference observed between control and porphyrin-treated samples when measured below the main lipid transition temperature disappeared at higher temperature. When the spin label was near the end of the hydrophobic tails, the symmetrical porphyrin derivative caused increase in fluidity, while the asymmetrical one slightly decreased it. To explain this phenomenon we propose that the asymmetrical derivative exerts a stronger ordering effect caused by its fluorophenyl group located at the level of the lipid heads, which is attenuated to the hydrophobic tails. The perturbing effect of the symmetric derivative could not lead to similar extent of ordering at the head groups and looses the hydrocarbon chains deeper in the membrane.

Effect of UVA radiation on membrane fluidity and radical decay in human fibroblasts as detected by spin labeled stearic acids.

The ultraviolet A (UVA) radiation component of sunlight (320-400 nm) has been shown to be a source of oxidative stress to cells via generation of reactive oxygen species. We report here some consequences of the UVA irradiation on cell membranes detected by electron paramagnetic resonance (EPR) spectroscopy. Paramagnetic nitroxide derivatives of stearic acid bearing the monitoring group at different depths in the hydrocarbon chain were incorporated into human fibroblasts membranes to analyze two main characteristics: kinetics of the nitroxide reduction and membrane fluidity. These two characteristics were compared for control and UVA-irradiated (0-250 kJ/m(2)) cells. The term relative redox capacity (RRC) was introduced to characterize and to compare free radical reduction measured by EPR with some well-known viability/clonogenicity tests. Our results showed that UVA-irradiation produces a more rigid membrane structure, especially at higher doses. Furthermore, we found that trends agree in survival measured by neutral red (NR), trypan blue (TB), and clonogenic efficiency compared with RRC values measured by EPR for low and medium exposure doses. Above 100 kJ/m(2), differences between these tests were observed. Antioxidant effect was modeled by alpha-tocopherol-acetate treatment of the cells before UVA irradiation. While NR, TB and clonogenicity tests showed protection at the highest UVA doses (>100 kJ/m(2)), results obtained with EPR measurements, both membrane fluidity and kinetics, or using MTT test did not exhibit this protective effect.