Volume 41, Issue 2

Objective: Human paraoxonase 1 (PON1) is an HDL-associated enzyme with anti-oxidant/anti-inflammatory properties that has been suggested to play an important protective role against coronary artery disease (CAD). The PON1 promoter -108C/T polymorphism has been analyzed in numerous association studies as a genetic marker for CAD, however, with controversial results. The aim of this study was to evaluate the association of PON-1 promoter -108C/T polymorphism with the risk of myocardial infarction (MI) in the Tunisian male population. Methods: A total of 815 subjects were recruited, including 318 healthy controls and 497 MI patients. Genotypes were determined by PCR-RFLP method. Genotype/allele frequencies were compared in patients and controls using the chi-square test. Results: Genotype distributions and allele frequencies of PON-1 promoter -108C/T polymorphism were different among the control and MI groups. Patients with MI had significantly higher frequency of the TT genotype compared to controls [29.2% vs. 25.5%; OR (95% CI), 1.67 (1.52-2.49); p=0.010]. The MI patient group showed a significant higher frequency of the T allele compared to the controls [0.56 vs. 0.51; χ 2 =8.61, p=0.013]. The association between the PON-1 promoter -108C/T polymorphism and MI remained significant after adjustment for other well-established cardiovascular risk factors. Conclusion: The present study showed a significant and independent association between the PON-1 promoter -108C/T polymorphism and MI in the Tunisian male population.

Objective: Heart failure is the end stage of many cardiac disorders. Worsening heart failure causes high mortality in these patients. In the present study, we aimed to elucidate and compare the biochemical predictors of worsening heart failure. Methods: One hundred one patients with heart failure were included in this study. Patients were divided into two groups according to their functional status. N-terminal pro-brain natriuretic peptide (NT-pro BNP), troponin T, serum and urine creatinine, blood urine nitrogen (BUN), eGFR, cystatin C, neutrophil gelatinase associated lipocalin (NGAL), C - reactive protein, hepatic transaminases and thyroid stimulating hormone levels were measured. Results: NT-pro BNP, troponin T, serum creatinine, BUN, cystatin C and NGAL levels were significantly higher but urine creatinine level and eGFR was lower in decompensated heart failure patients. In univariate analysis, age, cystatin C, NGAL, NT-pro BNP and serum creatinine and eGFR predicted worsening heart failure (WHF). In multivariate analysis, cystatin C and NT-pro BNP variables were found to be significant in predicting WHF. However, eGFR were determined at the limit of significance (p=0.053) with an high odds ratio 3.173 (95% CI:0.983-10.240). Cystatin C and NT-pro BNP concentrations were predictors of worsening heart failure. In ROC analysis, cystatin C is a better predictor of decompensated heart failure compared with NT-pro BNP and other predictors, and has a sensitivity of 82% and a specificity of 63%. Conclusion: This study revealed that cystatin C and NT-pro BNP were significant predictors of WHF, and cystatin C is slightly better predictor of WHF. Further studies are needed to confirm these results.

Objective: Leuconostoc mesenteroides AN39-1 has recently been isolated from Crataegus orientalis var. Orientalis. It produces inducible extracellular dextransucrase (EC 2.4.1.5) forming dextran from sucrose. The aim of this study was (1) to obtain constitutive, pH-resistant and thermostable dextransucrase, (2) to characterization of these dextransucrase. Methods: Mutagenesis was carried out on the parent strain (AN39-1) using UV, ethyl methane sulfonate, and N- methyl- N´-nitro-N-nitrosoguanidine. Dextransucrases from wild type (AN39-1) and the mutant strain (A26-2/11) were purified by polyethylene glycol (PEG) precipitation and characterized. Results: Mutants (A26, A26-2, and A26-2/11) hyper producing and constitutive for dextransucrase were isolated. The mutants (A26, A26-2, A26-2/11) produced 7.2, 8.1, and 2.0 times more dextransucrase activity as compared to parent strain on sucrose medium, respectively. In addition, the mutants produced dextransucrase on glucose medium with higher activities (3.0-5.8 times) than what the parental strain produced on sucrose medium. The mutant enzyme (A26-2/11) was much more thermostable than the native enzyme and resistant to pH more than dextransucrase of AN39-1. The dextransucrase from mutant strain was stable up to 35°C and pH of 7.5 for 3 hr. Conclusion: The structures of dextrans produced by wild type and mutant enzymes were similar to commercially produced B-512 F dextran. Thus, the newly dextransucrases produced by mutant strain could find industrial applications at higher temperature and pH.

Objective: The aim of present manuscript is to evaluate the efficiency of two microalgae strains -Chlorella vulgaris and Scenedesmus sp- in removal of some inorganic nutrients and heavy metals. Methods: For this aim the green microalgae (Chlorophyta), grown in controlled laboratory conditions, were used as biosorbent for the removal of six different concentrations of Antimony (Sb 3+ ), Manganese (Mn 2+ ), Copper (Cu 2+ ), Nickel (Ni 2+ ), Phosphate (PO 4 3- ) and Nitrate (NO 3 - ) which are prepared in aqueous solutions at conc. 0.1-1 mM for PO 4 3- ; 5-30 mM for NO 3 - ; 2,5-100 ppm for heavy metals. Besides, the effects of heavy metals and inorganic nutrients on the cell’s total carbohydrate and chlorophyll a-b content were investigated during 24 hours exposure. Results: According to the results, the average removal efficiency of Phosphate, Nitrate, Antimony, Manganese, Copper and Nickel on C. vulgaris biomass was determined 95.91%, 21.63%, 28.64%, 49.41%, 33.38% and 29.96% while 98.15%, 14.28%, 10.05%, 8.52%, 30.18% and 20.62% on Scenedesmus sp. cells, respectively. On the other hand, the average adsorption capacities of Sb 3+ , Mn 2+ , Cu 2+ , Ni 2+ , PO 4 3- and NO 3 - ions were confirmed 0.18, 0.38, 0.28, 0.15, 1.18 and 9.30 mg g -1 by C. vulgaris and 2.99, 0.96, 11.50, 11.33, 0.75 and 4.56 mg g -1 by Scenedesmus sp. biomass. Conclusion: Result of this study suggests that Chlorella vulgaris and Scenedesmus sp. have a remarkable ability on removal of excessive nutrients and heavy metals at laboratory conditions.

Objective: Determination of the factors associated with the intensive care unit (ICU) prognosis and mortality has important role in the clinical follow-up of the patients. Definition of novel biomarkers, beside older biomarkers available for evaluation of the outcome of these patients has been proposed. Platelet-activating factor acetylhydrolase (PAF-AH) is an enzyme that inactivates the platelet-activating factor. A reduction in the level of the PAF-AH has been demonstrated during systemic inflammation and multiple organ failure. This research aims to determine whether measurement of PAF-AH enzyme activity in ICUs can be used as a prognostic indicator like conventional biomarkers. Methods: Eighty five adult patients have been included. Following data have been recorded: preliminary C-reactive protein (CRP), lactate, albumin and PAF-AH values, APACHE II scores and discharge forms from ICU. Patients were divided in two groups with respect to APACHE II values: Group 1 (1-19) and Group 2 (≥20). Results: Observed mortality was 51.2%. In the APACHE II Group 2 patients, the values of CRP (p=0.001) and lactate (p=0.040) were significanty high, and the values of PAF-AH (p=0.008) and albumin (p=0.001) were significantly low. A statistically significant difference was found between PAF-AH values of exitus and alive patients (p=0.001). According to ROC analysis, the sensitivity and specificity of predicting mortality was 70.5% and 70.7% for CRP, 63.6% and 70.7% for lactate, 90.2% and 61.4% for albumin and 63.6% and 70% PAF-AH, respectively. Conclusion: Our study demonstrated that, in predicting the ICU mortality risk, sensitivity of the PAF-AH is similar to the sensitivity of the lactate, and specificity of the PAF-AH is better than that of the albumin. According to our results, PAF-AH can be included in the novel biomarkers.

Objective: For algal biotechnology, the primary barrier is the developing of cost effective photobioreactor operating in a high-efficiency. In this study, the effects of three different types of photobioreactors (bag, flat plate and bubble column) on the growth and sugar production of the diatom Cylindrotheca closterium were simultaneously investigated for 7 days of batch cultivation period. Methods: The photobioreactors were incubated at 21±2°C under the light intensity of 50 μmol photons m-2s-1 with a 12: 12 h light: dark cycle photoperiod at the air flow rate of 2 L min-1 for 7 days of batch productions. The turbidity (optical density), chlorophyll-a, exopolysaccharide (EPS) content and reducing sugar concentration were measured. Results: The maximum specific growth rate of 0.29 day −1 , which corresponded to the doubling time of 2.40 day, was obtained in the bag photobioreactor cultivation of C. closterium. It was found that the polyethylene bag photobioreactors are suitable for the production of diatoms as a closed photobioreactor. Conclusion: The key is not only the selection of geometrical configuration of photobioreactor, but also the determination of the light penetration path for cost effective photobioreactor design operating in high efficiency related to the algal productions.

Objective: The aim of the present study is to evaluate the effect of crocin on mRNA expression of antioxidant enzymes, SOD, CAT and GPX in the brain of the STZ induced diabetic rats. Methods: Thirty animals randomized in three groups containing ten animals in each group as follows; control (non-diabetic rats), DM (STZ-induced untreated diabetic rats), DM+crocin (STZ-induced diabetic rats treated with crocin,). Crocin was given at a dose of 20 mg/kg bw/day by gavage for 21 days. Results: STZ injection caused a significant increase in mRNA expression of antioxidant enzymes, SOD, CAT and GPX when compared to control group. Crocin given to diabetic rats significantly decreased mRNA expression of antioxidant enzymes, SOD, CAT and GPX when compared to DM group. Conclusion: The present study demonstrates that crocin can modulate mRNA expression of antioxidant enzymes, SOD, CAT and GPX and oxidative stress in the brain of the STZ induced diabetic rats.

Objective: Mycobacterium tuberculosis (MTB) is an obligate aerobe bacterial pathogen. Here, the citrate synthase (CS) family, an important component of aerobic respiration, was investigated in MTB. Methods: MTB genome was analyzed in silico to reveal the members of CS family. The nucleotide and amino acid sequences were retrieved from the NCBI database, and searched for the similarity using the NCBI BLAST tool. Sequence alignment and phylogenetic analysis were performed using MEGA6. The physicochemical parameters, cellular localization, HMM profiles, motif structure, 3D modeling, and the interactions of the proteins were analyzed using GPMAW, PSORTb, Pfam and SMART, MEME, Phyre2, and STRING databases, respectively. Results: The members of CS family in MTB were identified as CitA, GltA2, and PrpC. The CitA and PrpC were found to be closer in phylogeny than GltA2, and the trees of three proteins were shown to be similar to that constructed based on 16S rRNA in mycobacteria. The CitA contains two CS domains while a single CS domain is found in GltA2 and PrpC. Besides, LHGGA and MGFGHRVY motifs are conserved in MTB and various bacteria. The molecular weight and pI values of CitA, GltA2, and PrpC were calculated as 40.1, 47.9, and 42.9 kDa, and 5.41, 5.35, and 9.31, respectively. Cellular localization of the proteins was predicted as cytoplasm. The highest expression ratio was found to be for gltA2 followed by prpC and citA, respectively, in the retrieved RNA-seq datasets obtained from the aerobic log phase of MTB H37Rv. Conclusion: This comprehensive bioinformatics analysis of CS family in MTB has a contribution to the knowledge of the genetics and physiology of this pathogen.

In the present study we describe a patient who has interference due to paraproteinemia in her labaratory results. In a patient with a total protein concentration of 10.8 g/dL, a direct bilirubin result higher than total was detected. She also had discordant results in her whole blood count parameters. Further investigation was performed on this patient. Presence of any cold agglutinin and cryoglobulin was tested and excluded first. After 2-mercaptoethanol (2-ME) treatment, patient was idendified as Ig-M Kappa monoclonal gammapathy on immunofixation electrophoresis (IFE). Direct bilirubin interference disappeared after removal of the paraprotein by polyethylene glycol (PEG) precipitation. Laboratory specialist should know paraprotein interference and be able to manage it.

Objective: Prostate specific antigen is widely used for the diagnosis, treatment, and follow-up of prostate cancer. However, despite being organ-specific, PSA is not specific to cancer. As some patients with elevated PSA level have normal biopsy results and some others with low PSA levels have cancer diagnosed in biopsy examination, PSA creates diagnostic uncertainty both for clinicians and patients. Moreover, different PSA results received for the same subject at separate time points as well as smalllarge fluctuations in PSA levels perturb both sides. In a setting where there are so many unknowns we have PSA in our hands without any restrictions for ordering it. This study analyzed PSA orders, patient traffic, and economic burden within a 6-year period. Methods: The number of PSA tests and patient outcomes at a training and research hospital between October 2006 and May 2013 were evaluated. Results: Of 12107 tPSA orders, 73.6% were ordered by the urology clinic and 26.4% orders were made from other outpatient clinics. When patients at follow-up for prostate cancer are excluded because their tPSAs have to be more commonly checked, we detected that 28.22% of tests were ordered at intervals of less than 1 year. The average tPSA testing frequency was 91.84±1.21 days (0-330). The number of patients younger than 40 years who were tested for tPSA was 287. Of these, 25.43% were ordered by the urology clinic and the remaining by other medical branches. Conclusion: A state of chaos surrounds PSA order and interpretation. Neither patients nor physicians are aware of PSA-related outcomes. Therefore, each hospital should hold sessions on PSA testing and inform physicians about them. Furthermore, a detailed public education should be provided and seminars should be organized at the national level.