Effect of pulmonary exacerbations on long-term lung function decline in cystic fibrosis

It is unknown what proportion of long-term lung function decline in cystic fibrosis (CF) is explained by pulmonary exacerbations. The aim of this study was to determine how exacerbations requiring hospitalisation contribute to the course of CF lung disease. This was a retrospective cohort study. The primary outcome was the rate of decline of forced expiratory volume in 1 s (FEV(1)) % predicted. Out of 851 subjects, 415 (48.8%) subjects had ≥ 1 exacerbation. After adjustment for confounders, the annual rate of FEV(1) decline in those without an exacerbation was 1.2% per yr (95% CI 1.0-1.5), compared with 2.5% per yr (95% CI 2.1-2.8) in those with an exacerbation. The proportion of overall FEV(1) decline associated with ≥ 1 exacerbation was 52% (95% CI 35.0-68.9). For a given number of exacerbations, the annual rate of FEV(1) decline was greatest in subjects with ≤ 6 months between exacerbations. Half of FEV(1) decline seen in CF patients was associated with pulmonary exacerbations. Time between exacerbations, specifically ≤ 6 months between exacerbations, plays an important contribution to overall lung function decline. These findings support using time to next exacerbation as a clinical end-point for CF trials.     

The Global Lung Initiative 2012 reference values reflect contemporary Australasian spirometry

We aimed to ascertain the fit of the European Respiratory Society Global Lung Initiative 2012 reference ranges to contemporary Australasian spirometric data. Z‐scores for spirometry from Caucasian subjects aged 4–80 years were calculated. The mean (SD) Z‐scores were 0.23 (1.00) for forced expirtory volume in 1 s (FEV₁), 0.23 (1.00) for forced vital capacity (FVC), ?0.03 (0.87) for FEV₁/FVC and 0.07 (0.95) for forced expiratory flows between 25% and 75% of FVC. These results support the use of the Global Lung Initiative 2012 reference ranges to interpret spirometry in Caucasian Australasians.     

Health-Related Quality of Life,Treatment Efficacy,and Hemodialysis Patient Outcome

The aim of the study was to examine the influence of improved treatment of hemodialysis (HD) patients on their health-related quality of life (HrQoL) and to assess the predictive value of HrQoL dimensions on patient outcome. The prospective cohort study involved 102 HD patients, and their clinical and laboratory parameters and HD adequacy indices were followed from 2001 to 2007. HrQoL was measured using KDQOL-SF Version 1.3 in 2001, 2004, and 2007. During a six-year period, quality of HD and anemia treatment improved and resulted in significant increase of mean Kt/V (1.2–1.56) and hemoglobin levels (86.5–115.6 g/L). All four HrQoL dimensions (i.e., physical, mental health, kidney disease target issues, and patient satisfaction) remained unchanged, but significant improvement in several HrQoL physical health domains and the effects of kidney disease domain was found. Mortality rate decreased from 18.6% to 7.14% per year. Age was associated positively, but kidney disease target issue score negatively, with patient death. Improved HD adequacy and anemia treatment in HD patients were followed with maintenance of all four HrQoL dimensions unchanged over six years. Moreover, an improvement in several physical health domains and the effects of kidney disease domain was found. Age and kidney disease target issue appeared as significant predictors of patients' death.     

Factors influencing the acquisition of Stenotrophomonas maltophilia infection in cystic fibrosis patients

BackgroundStenotrophomonas maltophilia is one of the most common multi-drug resistant organisms causing pulmonary infections in CF patients. It is unknown whether S. maltophilia infection follows the same pattern and shares similar risk factors for acquisition as described for Pseudomonas aeruginosa.MethodsWe examined all clinical events from 1997 to 2008 in the Toronto CF Database to identify risk factors for the acquisition of S. maltophilia and to define distinct patterns of infection.ResultsWe followed 601 patients over 12 years, during which time one quarter of subjects had at least one positive culture for S. maltophilia; the incidence rate was slightly higher in children (11.6/100 person years) compared with adults (10.6/100 person years). Using multi-variable Cox proportional hazards models, steeper rate of FEV₁ decline was a significant risk factor for S. maltophilia acquisition, whereas new infections were less likely to occur with greater oral antibiotic use and a history of Burkholderia cepacia complex infection.ConclusionsThis study illustrates the evolution of S. maltophilia infection over time in a large cohort of adults and children with CF. Younger CF patients, and those with greater lung function decline were at increased risk of S. maltophilia infection. The use of oral antibiotics to maintain lung function may be a way of decreasing the risk of infection. However, the optimal management of CF patients with persistent S. maltophilia infection is not yet known and requires further studies.     

Cardiologic predictors of sudden death in patients with myotonic dystrophy type 1

The aim of this study was to analyze survival, causes of death and cardiologic predictors of sudden death in a large cohort of patients with myotonic dystrophy type 1 (DM1). The study was comprised of 171 adult DM1 patients hospitalized at the Neurology Clinic in a 20-year period. Severe electrocardiographic (ECG) abnormality included at least one of the following: rhythm other than sinus, PR interval of ?240 ms, QRS complex duration of 120 ms or more, and second-degree or third-degree atrioventricular (AV) block. Survival data were analyzed by the Kaplan–Meier test, log–rank test and Cox regression analysis. During the mean follow-up period of 9.4 ± 5.4 years, a pacemaker was implanted in 5.8% of DM1 patients and 14% of patients died. The mean age at death was 55.6 ± 12.5 years. The most common causes of death in our cohort were sudden death (41.7%) and respiratory failure (29.2%). The presence of palpitations (hazard ratio [HR] = 4.7, p < 0.05) and increased systolic blood pressure (HR = 9.8, p < 0.05) were significant predictors of sudden death. Among ECG parameters, severe ECG abnormality (HR = 4.7, p < 0.05), right bundle branch block (RBBB; HR = 3.9, p < 0.05) and bifascicular block (HR = 5.8, p < 0.05) were significant predictors of sudden death.     

Validation of flavonoids as potential dipeptidyl peptidase III inhibitors: Experimental and computational approach

Fifteen flavonoids were studied for their inhibitory activity against human dipeptidyl peptidase III (hDPP III) combining an in vitro assay with an in silico molecular modeling study. All analyzed flavonoids showed inhibitory effects against hDPP III with the IC₅₀ values ranging from 22.0 to 437.2 μm . Our 3D QSAR studies indicate that the presence of hydrophilic regions at a flavonoid molecule increases its inhibitory activity, while the higher percentage of hydrophobic surfaces has negative impact on enzyme inhibition. Furthermore, molecular dynamics (MD) simulations of the complex of hDPP III with one of the most potent inhibitors, luteolin, were performed, and binding mode analysis revealed that the 3′ and 4′ hydroxyl group on B‐ring as well as 5 and 7 hydroxyl group on A‐ring helps luteolin to interact with the Asn391, Asn406, Tyr417, His450, Glu451, Val447, Glu512, Asn545, Gln566, and Arg572 residues. The MD results clearly provide valuable information explaining the importance of flavonoid hydroxyl groups in the mechanism for the binding pattern at the active site of hDPP III.     

The difference of situational efficiency and indicators of situational-motoric skills between national teams in the World handball championship

This research focused on the establishment of difference in situational-motoric skills and situational efficacy in defence and offence using audio-visual records of the XIX Junior World Handball Championship 2013, Bosnia and Herzegovina. The differences between players of Bosnian and Herzegovinian national team and the first four placed national teams (Sweden, Spain, France and Croatia) by specific playing positions (left back, centre back and right back) were determined. In the case of situational-motoric skills, two indicators (variables) (total/mean number of sprints from the offence to defence, and the total/mean number of jumps in the offence) were analysed, while in the case of the situational efficacy, one variable (total/mean number of fouls 9 m in the game 1:1) was analysed. To establish partial quantitative differences of variables, the pondered mean difference (MD) was used, as well as significance. Observed results indicated that differences existed in situational-motoric skills and situational efficacy between analysed players, according to player’s positions. Therefore, planning of the training process should be directed to improve technical and tactical elements of handball game and the level of the physical preparation to achieve better results, both individually and as a team.     

Fcgamma receptors are crucial for the expression of acquired resistance to virulent Salmonella enterica serovar Typhimurium in vivo but are not required for the induction of humoral or T-cell-mediated immunity

Antibodies play an important role in immunity to Salmonella enterica. Here we evaluated the requirement for Fcgamma receptors in host resistance to S. enterica using an in vivo model of systemic infection. We show that mice lacking FcgammaRI, II and III can control and clear a primary infection with S. enterica micro-organisms of low virulence, but are impaired in the expression of vaccine-induced acquired immunity to oral challenge with virulent bacteria. We also show that, in vivo, FcgammaRI, II, III(-/-) mice were able to mount efficient T-helper 1 type T-cell responses and antibody responses specific for S. enterica. The work indicates that targeting S. enterica to FcgammaR is needed for the expression of vaccine-induced acquired immunity, but is not essential for the engenderment of T- and B-cell immunity to the bacterium in vivo.     

Effect of human glutathione S-transferase hGSTP1-1 polymorphism on the detoxification of reactive metabolites of clozapine,diclofenac and acetaminophen

Recent association studies suggest that genetically determined deficiencies in GSTs might be a risk factor for idiosyncratic adverse drug reactions resulting from the formation of reactive drug metabolites. hGSTP1-1 is polymorphic in the human population with a number of single nucleotide polymorphisms that yield an amino acid change in the encoded protein. Three allelic variants of hGSTP1-1 containing an Ile105Val or Ala114Val substitution, or a combination of both, have been the most widely studied and showed different activity when compared to wild-type hGSTP1-1*A (Ile105/Ala114). In the present study, we studied the ability of these allelic variants to catalyze the GSH conjugation of reactive metabolites of acetaminophen, clozapine, and diclofenac formed by bioactivation in in vitro incubations by human liver microsomes and drug metabolizing P450 BM3 mutants. The results show that effects of the change of amino acid at residue 105 and 114 on conjugation reactions were substrate dependent. A single substitution at residue 105 affects the ability to catalyze GSH conjugation, while when both residue 105 and 114 were substituted the effect was additionally enhanced. Single mutation at position 114 did not show a significant effect. The different hGSTP1-1 mutants showed slightly altered regioselectivities in formation of individual GSH conjugates of clozapine which suggests that the binding orientation of the reactive nitrenium ion of clozapine is affected by the mutations. For diclofenac, a significant decrease in activity in GSH-conjugation of diclofenac 1′,4′-quinone imine was observed for variants hGSTP1-1*B (Val105/Ala114) and hGSTP1-1*C (Val105/Val114). However, since the differences in total GSH conjugation activity catalyzed by these allelic variants were not higher than 30%, differences in inactivation of reactive intermediates by hGSTP1-1 are not likely to be a major factor in determining interindividual difference in susceptibility to adverse drug reactions induced by the drugs studied.