Evaluation of exercise capacity with cardiopulmonary exercise test and B-type natriuretic peptide in adults with congenital heart disease

Background: Adult patients with congenital heart disease (CHD) usually find their exercise capacity satisfactory. However, objective evaluation is important for diagnostic and prognostic purposes. The aim of this study was to evaluate exercise capacity using cardiopulmonary exercise tests and measurement of serum B-type natriuretic peptide (BNP) levels in adult patients with CHDs, both in the entire study cohort and in subjects with individual types of cardiac lesions, as well as to verify the relation between BNP level and cardiac performance. Methods: The study group included 265 patients (136 males; mean age 34.4 ± 11.6 years) 173 of whom were operated on at the mean age of 9.2 ± 7.3 years. They represented the following types of CHD: 72 patients - surgically corrected coarctation of the aorta, 62 - surgically corrected tetralogy of Fallot, 28 - Ebstein anomaly, 26 - patent atrial septal defect, 24 - Eisenmenger syndrome, 20 - uncorrected or palliated complex cyanotic lesions, 11 - corrected transposition of the great arteries (TGA), 14 - TGA after Senning operation, and 8 - common ventricle after Fontana operation. The control group consisted of 39 healthy individuals (17 males) with a mean age of 35.8 ± 9.3 years. Results: According to NYHA classification, 207 patients were recognized as representing class I symptoms, 47 subjects class II, and 11 class III. Cardiopulmonary exercise revealed significantly reduced exercise capacity in adults with CHD in general, compared to control subjects: maximal oxygen uptake (VO2max) was 23.3 ± 6.9 vs. 33.6 ± 7.2 mL/kg/min, respectively (p = 0.00001); maximum heart rate at peak exercise (HRmax) -161.1 ± 33.2 vs. 179.6 ± 12.3 bpm (p = 0.00001); respiratory workload (VE/VCO2slope) - 35.7 ± 9.7 vs. 26.3 ± 3.1 (p = 0.00001); and forced vital capacity (FVC) - 3.8 ± 1.1 vs. 4.6 ± 0.7 L (p = = 0.00003). Various degrees of peak VO2max reduction were observed across the spectrum of CHD. Patients after repair of aortic coarctation demonstrated the highest VO2max (26.8 ± 6.6 mL/kg/min), and the lowest was demonstrated by patients with Eisenmenger syndrome (12.8 ± 4.8; ANOVA p = 0.00001). Serum BNP levels in the study group were higher than in the controls: 55.4 ± 67.5 vs. 13.9 ± 13.7 pg/mL, respectively (p = 0.00001). Various degrees of BNP level increase were found across the spectrum of CHD. Patients after repair of aortic coarctation demonstrated the lowest BNP level (24.8 pg/mL), and the highest level was found in patients with cyanotic defects (120.7 pg/mL; ANOVA p = 0.00001). BNP levels across the NYHA classes were as follows: I - 35.7 pg/mL, II - 94.1 pg/mL, and III - 225.6 pg/mL. BNP levels showed negative correlation with VO2max (r = –0.525, p = 0.0001), FVC (r = = –0.349, p = 0.00001), FEV1 (r = –0.335, p= 0.00001), and positive correlation with VE/VCO2slope (r = 0.447, p = 0.00001). Conclusions: The exercise capacity of patients with CHD is, in general, compromised, most strikingly in patients suffering from pulmonary hypertension and cyanosis. Serum BNP levels in these subjects are increased and correlate well with exercise capacity. BNP level is higher in patients with cyanotic CHDs

Cardiopulmonary exercise test in the evaluation of exercise capacity, arterial hypertension, and degree of descending aorta stenosis in adults after repair of coarctation of the aorta

Background: Despite effective repair of coarctation of the aorta (CoAo), arterial hypertension (AH) and early coronary artery disease that may result in heart failure. The aim of the study was to evaluate exercise capacity by a cardiopulmonary exercise test in patients after of CoAo repair, and to determine relations between these parameters and the presence of AH, residual stenosis of the descending aorta (AoD) and the patient’s age at the time of the surgery. Methods: 74 patients at mean age 31.2 ± 9.8 years. The controls: 30 at mean age 32.2 ± 6.6. Descending aorta (AoD) gradient was evaluated by echocardiography. The group with residual AoD stenosis: ≥ 25 mm Hg (AoD+) 32 patients and AoD–: 41 patients. Subgroups without AH (AH–, n = 32), exercise-induced AH (AHex, n = 10), persistent AH (AH+, n = 32). The maximum exercise test was performed. Results: A comparison of the study and control groups: VO2max: p = 0.0001), VO2max%: p=0.0001 and VE/VCO2: p = 0.001. Negative correlation: between VO2max and the age at the time of surgery: p = 0.004) and a positive: between VE/VCO2 and age at surgery: p = 0.005. No differences were observed between the AoD+ and AoD– groups with respect to cardiopulmonary parameters. A comparison of the AH+ and AH– groups revealed: VO2max: p = 0.01, VO2max%: p = 0.02 and VE/VCO2: p = 0.003. A comparison of the AHex and AH– groups showed VE/VCO2: p = 0.01. Conclusions: The exercise capacity of adults after surgical CoAo repair is reduced. This is more pronounced in patients with AH and those operated on at a more advanced age, but not in AoD+. (Cardiol J 2007; 14: 76–82

Survey of present data on photon structure functions and resolved photon processes

Present data on the partonic content of the photon from LEP, TRISTAN and HERA accelerators are reviewed and the essential aspects of the underlying ideas and methods are pointed out. Results of the unpolarized photon structure function F_2 from DIS_{e gamma} experiments and on large p_T jet production processes in the resolved gamma-gamma collisions are presented for both real and virtual photons. The results of analysis of the hadronic final state accompanying the DIS_{e gamma} measurements, showing some discrepancies with the Monte Carlo models, are collected together and presented as a separate issue. Also results on the DIS_{e gamma} with leptonic final states are shown. The results from resolved real and virtual photon processes at HERA collider based on the single and double jet events, also charged particles and prompt photons, are presented. In the context of virtual photon processes the data for forward jet and forward particle production are included. In addition a short presentation of the recent data on the heavy quark content of the photon is given. Related topics - the polarized (spin dependent) structure functions for the real and virtual photon, the structure function of the electron and the photonic content of the proton are also shortly mentioned.Comment: latex, 220 pages, 195 ps figures; extended and updated version of hep-ph/9806291; to appear in Physics Report

High-resolution nerve ultrasound abnormalities in POEMS syndrome: a comparative study

Background: High-resolution nerve ultrasound (HRUS) has been proven to be a valuable tool in the diagnosis of immune-mediated neuropathies, such as chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, M-protein, skin changes) is an important differential diagnosis of CIDP. Until now, there have been no studies that could identify specific HRUS abnormalities in POEMS syndrome patients. Thus, the aim of this study was to assess possible changes and compare findings with CIDP patients. Methods: We retrospectively analyzed HRUS findings in three POEMS syndrome and ten CIDP patients by evaluating cross-sectional nerve area (CSA), echogenicity and additionally calculating ultrasound pattern scores (UPSA, UPSB, UPSC and UPSS) and homogeneity scores (HS). Results: CIDP patients showed greater CSA enlargement and higher UPSS (median 14 vs. 11), UPSA (median 11.5 vs. 8) and HS (median 5 vs. 3) compared with POEMS syndrome patients. However, every POEMS syndrome patient illustrated enlarged nerves exceeding reference values, which were not restricted to entrapment sites. In CIDP and POEMS syndrome, heterogeneous enlargement patterns could be identified, such as inhomogeneous, homogeneous and regional nerve enlargement. HRUS in CIDP patients visualized both increased and decreased echointensity, while POEMS syndrome patients pictured hypoechoic nerves with hyperechoic intraneural connective tissue. Discussion: This is the first study to demonstrate HRUS abnormalities in POEMS syndrome outside of common entrapment sites. Although nerve enlargement was more prominent in CIDP, POEMS syndrome patients revealed distinct echogenicity patterns, which might aid in its differentiation from CIDP. Future studies should consider HRUS and its possible role in determining diagnosis, prognosis and treatment response in POEMS syndrome

MDM2 Associates with Polycomb Repressor Complex 2 and Enhances Stemness-Promoting Chromatin Modifications Independent of p53

SummaryThe MDM2 oncoprotein ubiquitinates and antagonizes p53 but may also carry out p53-independent functions. Here we report that MDM2 is required for the efficient generation of induced pluripotent stem cells (iPSCs) from murine embryonic fibroblasts, in the absence of p53. Similarly, MDM2 depletion in the context of p53 deficiency also promoted the differentiation of human mesenchymal stem cells and diminished clonogenic survival of cancer cells. Most of the MDM2-controlled genes also responded to the inactivation of the Polycomb Repressor Complex 2 (PRC2) and its catalytic component EZH2. MDM2 physically associated with EZH2 on chromatin, enhancing the trimethylation of histone 3 at lysine 27 and the ubiquitination of histone 2A at lysine 119 (H2AK119) at its target genes. Removing MDM2 simultaneously with the H2AK119 E3 ligase Ring1B/RNF2 further induced these genes and synthetically arrested cell proliferation. In conclusion, MDM2 supports the Polycomb-mediated repression of lineage-specific genes, independent of p53

Vacuolar organization in the nodule parenchyma is important for the functioning of pea root nodules

Different models have been proposed to explain the operation of oxygen diffusion barrier in root nodules of leguminous plants. This barrier participates in protection of oxygen-sensitive nitrogenase, the key enzyme in nitrogen fixation, from inactivation. Details concerning structural and biochemical properties of the barrier are still lacking. Here, the properties of pea root nodule cortical cells were examined under normal conditions and after shoot removal. Microscopic observations, including neutral red staining and epifluorescence investigations, showed that the inner and outer nodule parenchyma cells exhibit different patterns of the central vacuole development. In opposition to the inner part, the outer parenchyma cells exhibited vacuolar shrinkage and formed cell wall infoldings. Shoot removal induced vacuolar shrinkage and formation of infoldings in the inner parenchyma and uninfected cells of the symbiotic tissue, as well. It is postulated that cells which possess shrinking vacuoles are sensitive to the external osmotic pressure. The cells can give an additional resistance to oxygen diffusion by release of water to the intercellular spaces

YUVA: AN E-HEALTH MODEL FOR DEALING WITH PSYCHOLOGICAL ISSUES OF ADOLESCENTS

The stressful lifestyle of the present age is leading to several psychological and behavioral issues. Adolescents and young adults are perhaps the worst effected due to the demanding everyday life leading to depression, anxiety and related issues. To deal with such issues the present study recommends an easy and adaptable electronic platform for e-psychology systems by using ICT tools and services and can be used to deal with various health (physical & mental) issues of adolescents. A model named “YUVA” based on RWD (responsive web development) which can run on any desktop or mobile phones is suggested for the benefit of adolescents trying to cope up with psychological issues. The purpose of this application is to provide information concerning different issues like health, education, recent studies, Government Initiatives etc. It incorporates several facilities like self assessment tests, registration facility for counsellors, dieticians, instructors etc. so that they can be contacted at the hour of need. The implementation is provided on .NET platform for wide deployment and adaptability

CAM-related changes in chloroplastic metabolism of Mesembryanthemum crystallinum L.

Crassulacean acid metabolism (CAM) is an intriguing metabolic strategy to maintain photosynthesis under conditions of closed stomata. A shift from C3 photosynthesis to CAM in Mesembryanthemum crystallinum plants was induced by high salinity (0.4 M NaCl). In CAM-performing plants, the quantum efficiencies of photosystem II and I were observed to undergo distinct diurnal fluctuations that were characterized by a strong decline at the onset of the day, midday recovery, and an evening drop. The temporal recovery of both photosystems’ efficiency at midday was associated with a more rapid induction of the electron transport rate at PSII. This recovery of the photosynthetic apparatus at midday was observed to be accompanied by extreme swelling of thylakoids. Despite these fluctuations, a persistent effect of CAM was the acceptor side limitation of PSI during the day, which was accompanied by a strongly decreased level of Rubisco protein. Diurnal changes in the efficiency of photosystems were parallel to corresponding changes in the levels of mRNAs for proteins of PSII and PSI reaction centers and for rbcL, reaching a maximum in CAM plants at midday. This might reflect a high demand for new protein synthesis at this time of the day. Hybridization of run-on transcripts with specific probes for plastid genes of M. crystallinum revealed that the changes in plastidic mRNA levels were regulated at the level of transcription