Targeting outer membrane protein A (OmpA) - inhibitory effect of 2'-hydroxychalcone derivatives on Acinetobacter baumannii and Candida albicans dual-species biofilm formation.

Biofilm production facilitates microbial colonization of wounds and catheters. Acinetobacter baumannii produces high levels of biofilm and causes difficult-to-treat nosocomial infections. Candida albicans is another strong biofilm producer which may facilitate A. baumannii adhesion by providing hyphae-mediated OmpA-binding sites. Here we tested the potential of 2'-hydroxychalcones to inhibit dual-species biofilm production of A. baumannii and Candida spp., and further predicted the mechanism of structure-related difference in activity. The results suggest that 2'-hydroxychalcones exhibit potent activity against Candida spp./A. baumannii dual-species biofilm production. Particularly active was trifluoromethyl-substituted derivative (p-CF3), which decreased C. albicans/A. baumannii biomass produced on vein-indwelling parts of the central venous catheterization set by up to 99%. Further, higher OmpA-binding affinity was also calculated for p-CF3, which together with demonstrated significant ompA-downregulating activity, suggests that superior antibiofilm activity of this chalcone against the tested dual-species community of A. baumannii is mediated through the OmpA.

Interactions of the eNOS and ACE genes and cigarette smoking in chronic obstructive pulmonary disease.

Background: Chronic obstructive pulmonary disease (COPD) is a complex disorder with unexplained heritability. Interactions of genetic and environmental factors are thought to be crucial in COPD. So, we aim to examine interactions of the endothelial nitric oxide synthase (eNOS) and angiotensin converting enzyme (ACE) genes and cigarette smoking in COPD. Methods: The eNOS G 894T and ACE ID variants were analyzed in 122 COPD patients and 200 controls from Serbia. The effect of the variants on COPD was assessed by logistic regression. Interactions between eNOS, ACE and cigarette smoking in COPD were evaluated using a case-control model. Interaction between the genes was analyzed in silico. Results: No effect of the eNOS G 894T and ACE ID variants on COPD was found in our study. Gene-gene interaction between the eN OS T T and A CE D was identified (p=0.033) in COPD. The interaction is realized within the complex network of biochemical pathways. Gene-environment interactions between the eNOS T and cigarette smoking (p=0.013), and the ACE II and cigarette smoking (p=0.009) were detected in COPD in our study. Conclusions: This is the first research to reveal interactions of the eNOS and ACE genes and cigarette smoking in COPD progressing our understanding of COPD heritability and contributing to the development of appropriate treatments.

Questionable Reliability of Homocysteine as the Metabolic Marker for Folate and Vitamin B12 Deficiency in Patients with Chronic Obstructive Pulmonary Disease.

BACKGROUND: An increased homocysteine (Hcy) concentration may represent a metabolic marker of folate and vitamin B12 deficiency, both significant public health problems. For different reasons, patients with chronic obstructive pulmonary disease (COPD) are prone to these deficiencies. The study evaluates the reliability of Hcy concentration in predicting folate or vitamin B12 deficiency in these patients. METHODS: A group of 50 COPD patients (28 males/22 females, age (χ̄±SD=49.0±14.5) years was enrolled. A chemiluminescent microparticle immunoassay was applied for homocysteine, folate and vitamin B12 concentration. Kolmogorov-Smirnov, Mann-Whitney U and χ2 tests, Spearman's correlation and ROC analysis were included in the statistical analysis, with the level of significance set at 0.05. RESULTS: Average (SD) concentrations of folate and vitamin B12 were 4.13 (2.16) µg/L and 463.6 (271.0) ng/L, whereas only vitamin B12 correlated with the Hcy level (P=-0.310 (R=0.029)). Gender related differences were not significant and only a borderline significant correlation between age and folate was confirmed (R=0.279 (P=0.047)). The incidence of folate and vitamin B12 deficiency differed significantly (P=0.000 and P<0.000 for folate and vitamin B12 respectively), depending on the cutoff used for classification (4.4, 6.6 and 8.0 µg/L - folate; 203 and 473 ng/L - vitamin B12). ROC analyses failed to show any significance of hyperhomocysteinemia as a predictor of folate or vitamin B12 deficiency. CONCLUSION: Reliability of the Hcy concentration as a biomarker of folate or vitamin B12 depletion in COPD patients is not satisfactory, so their deficiency cannot be predicted by the occurrence of HHcy.

Clinical characteristics of first venous thrombosis among women under and over 45 years of age.

INTRODUCTION: Venous thromboembolism is a multifactorial disease defined by multiple interactions between genetic and acquired risk factors. After coronary heart disease and stroke, venous thromboembolism is the most common cause of cardiovascular death and disability. MATERIAL AND METHODS: In order to investigate the clinical characteristics of first venous thromboembolism, 447 women younger than 45 and 174 over 45 years of age with confirmed venous thromboembolism, who had been tested for the presence of thrombophilia in the period 1998-2012, were included in the study. RESULTS: Proximal deep vein thrombosis occurred most often among young women, while distal deep vein thrombosis was the most frequent in the older group. The most common reported risk for venous thromboembolism observed in 49.8% of the young women was pregnancy and puerperium, while 25.2% of them developed venous thromboembolism without any obvious cause. Among women over the age of 45, venous thromboembolism developed without an obvious cause in 38.5%, while malignant disease was identified as the most important risk factor in 23% of them. Thrombophilia was observed in 48.7% of the young women in comparison to 28.7% of the older ones (p < 0.0001). As for venous thromboembolism recurrence, it developed in 26.3% of young women and 17.8% of the older ones (p = 0.03). CONCLUSION: Younger women developed more severe forms of thrombosis than the older ones. Inherited risk factor for thrombosis was detected in almost half of all young women, and in every fourth elderly women. With the exception of factor V Leiden mutation, other types of congenital thrombophilia are almost negligible among older women. Therefore, thrombophilia testing in case of first thrombosis is fully justified only in young women.

Coexistence of hypofibrinogenemia and factor V Leiden mutation: is the balance shifted to thrombosis?

Congenital hypofibrinogenemia and afibrinogenemia are usually associated with an increased risk of bleeding, but occurrence of arterial or venous thrombosis has also been reported in individuals with fibrinogen deficiency. This study reports on a 25-year-old patient with hypofibrinogenemia (fibrinogen 0.6 g/l) and congenital thrombophilia due to heterozygous factor V Leiden mutation who developed spontaneous deep-vein thrombosis (DVT) in the right lower extremity. Regardless of hypofibrinogenemia, he was receiving anticoagulant therapy over 6 months, with no occurrence of bleeding. His father is also a heterozygous carrier of factor V Leiden, but with normal fibrinogen level and he remained asymptomatic despite having experienced surgery in the past. This case, as well as data from literature, suggests that risk of thrombosis in carriers of factor V Leiden mutation is not counterbalanced by moderate congenital hypofibrinogenemia, and that antithrombotic prophylaxis should not be omitted in high-risk situations for occurrence of thrombosis in patients with coinheritance of hypofibrinogenemia and factor V Leiden mutation.

[Factor V Leiden, FII G20210A, MTHFR C677T mutations as risk factors for venous thrombosis during pregnancy and puerperium].

BACKGROUND: Venous thrombosis is the most common cause of obstetric morbidity and mortality during pregnancy and puerperium. The incidence of pregnancy-associated venous thrombosis varies from 1 in 1000 to 1 in 2000 deliveries. Factor V G1691A (FV Leiden), FII G20210A and MTHFR C677T mutations are the most common genetic risk factors for thromboembolism. The aim of this study was to establish the presence of these risk factors in a group of women with an episode of deep venous thrombosis during pregnancy or puerperium. METHODS: The study was carried in a group of 45 women with the first episode of deep venous thrombosis during pregnancy or puerperium. The patients with antiphospholipid antibodies, antithrombin III, protein C or protein S deficiency, and autoimmune and malignant diseases were excluded from the study. FV Leiden, FII G20210A, and MTHFR C677T mutations were detected by polymerase chain reaction, followed by digestion with specific restriction enzymes. RESULTS: Twenty heterozygous carriers of the FV Leiden mutation and one homozygous carrier were detected, which represents the frequencies of 44.4% and 2.2%, respectively. For the FII G20210A mutation, six heterozygous carriers were identified, giving the frequency of 13.3%. The MTHFR C677T mutation was observed in 31 patients (22 heterozygous and 9 homozygous carriers) which represents the frequencies of 48.9% and 20%, respectively. CONCLUSION: Our study suggested that the obligatory testing for FV Leiden and FII G20210A mutations was strongly recommended in women with history of venous thrombosis during pregnancy and puerperium. We found a slight effect of MTHFR 677T allele, but it should be considered in association with other risk factors.