Assessment of antioxidant system status before and after operation in neonates with congenital heart disease.

Background/Aim: Oxidative stress is considered to have a significant role in the development of cardiovascular diseases (CVDs) as well as many other diseases. Therefore, the purpose of the study is to evaluate the antioxidant system status at pre- and post-operative period in newborns with congenital heart disease (CHD) requiring operation. Materials and Methods: Fifty CHD patients participated in this research. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and thiobarbituric acid reactive substances (TBARS) levels were studied in blood samples. RACHS-1 score, blood lactate levels, and hypoxic events were also recorded. Comparisons of antioxidant system parameters were conducted at pre- and post-operative periods and also between exitus and discharged groups. Results: GPx activity and TBARS levels were significantly higher in the pre-operative period than post-operative period though the other antioxidant enzymes were not altered. In pre-operative period, GPx activity was low in addition to rarer hypoxic events in the discharged group. Also, a negative correlation was found between SOD and GPx activities in pre-operative period. Conclusion: The results provide fundamental data showing the lowered GPx activity and TBARS levels considered as sensitive oxidative biomarkers after the operation. It was assumed that antioxidant system parameters might show changes after the operation, and GPx is prominent for resistance to hypoxic conditions. Post-operative reduction of GPx and TBARS levels is significant for evaluating the antioxidant system alterations after the operation. However, further investigations follow long-term duration for post-operative monitoring to estimate how antioxidant system status changes to improve the treatment of the health condition.

Prognostic Value of Cardiopulmonary Exercise Test Parameters in Ventricular Assist Device Therapy.

Cardiopulmonary exercise test (CPET) parameters are established prognosticators in heart failure. However, the prognostic value of preimplantation and postimplantation CPET parameters in left ventricular assist device (LVAD) therapy is unclear and it is evaluated in this study. Adult patients who were implanted with an LVAD and underwent CPET during the preimplantation or postimplantation period were retrospectively analyzed. Five CPET parameters were calculated: vO2 max, oxygen uptake efficiency slope (OUES), VE/vCO2 Slope, VE/vCO2 min, and VE/vCO2 max. The relationship between CPET parameters and postimplantation outcomes was evaluated with multivariable analysis. Pre and postimplantation CPET cohorts included 191 and 122 patients, respectively. Among preimplantation CPET parameters: vO2 max and OUES were associated with 1, 3, and 5 year mortality, VE/vCO2 min was associated with 3 and 5 year mortality, whereas VE/vCO2 Slope was associated with 5 year mortality. From postimplantation CPET parameters: vO2 max was an independent predictor of 3 and 5 year mortality, whereas VE/vCO2 max was an independent predictor of 3 year mortality following LVAD implantation. Preimplantation CPET parameters have a prognostic value for long-term survival following LVAD implantation, whereas their association with early postimplantation outcomes appears to be weaker. Postimplantation vO2 max and VE/vCO2 max values are associated with survival on device support and may provide a second chance for prognostication in patients without preimplantation CPET data.

Adjunctive role of immunohistochemical expression of Nucleostemin in differentiation of grade II and III diffuse astrocytomas.

AIMS: Astrocytomas are common tumors and grade is an important parameter in determining the treatment modalities. Tumor proliferation activity should be determined for the differentiation of grades II and III tumors. In difficult cases, an auxiliary parameter is required. Nucleostemin (NS) is nucleolar Guanosine triphosphate (GTP)-binding protein 3. It has important roles in cell proliferation, cell cycle regulation, self-renewal, and apoptosis. In this study, we investigated whether the level of NS expression is different in grades II and III astrocytomas. SETTINGS AND DESIGN: Adults diagnosed with grades II and III astrocytomas were included in the study. MATERIAL AND METHODS: Paraffin blocks that best reflected tumor morphology were studied via immunohistochemical staining for NS. Only nuclear staining was evaluated; cytoplasmic staining was not considered. STATISTICAL ANALYSIS USED: Fisher's exact test, continuity corrections, and Pearson's Chi-square tests were used in the crosstabs. The survival analysis was based on the Kaplan-Meier method. RESULTS: Only 20% (6/30) of grade II tumors had high intensity staining, while 54,2% (13/24) of grade III tumors had high staining intensity. NS was significantly more intense in grade III tumors than grade II tumors. In cases with high NS expression, survival was significantly shorter than the cases with low expression. CONCLUSION: NS is significantly higher expressed in grade III tumors than grade II tumors. In difficult cases, it can be used as a useful proliferation marker in the differentiation of grades II and III astrocytomas.

Oleofoams: Properties of Crystal-Coated Bubbles from Whipped Oleogels-Evidence for Pickering Stabilization.

Interfacially stabilized nonaqueous lipid-based foams, which we name here oleofoams, are rarely encountered as opposed to the large number of aqueous foams stabilized by molecular or particulate emulsifiers. There is no case well described in the literature with a convincing characterization of the interfacial contribution to oleofoam stability. Methods for filling this gap are described here, which reach out to a large part of the lipid phase diagram. We bring here complete evidence that lipidic crystals made of a high fraction of fully soluble monoglyceride (MG) in oil do not only adsorb at the oil-air interface but also can easily form a jammed, closely packed layer of crystals around the bubbles of a foam produced by whipping (Pickering effect). Very fine bubbles, soft textures, or firmer ones such as for shaving foams could be obtained, with a high air fraction (up to 75%), which is unprecedented. A thin, jammed layer of crystals on bubbles can cause bubbles to retain nonspherical shapes in the absence of bulk effects for times much longer than the characteristic capillary relaxation time for bare bubbles, which is actual evidence for Pickering-type interfacial stabilization. By comparing to foams obtained by depressurization, we show that whipping is necessary for bubble wrapping with a layer of crystals. The origin of high stability against Ostwald ripening at long times is also discussed. Furthermore, we show that these Pickering whipped foams have rheological properties dominated by interfacial or film contributions, which is of high interest for food and cosmetics applications because of their high moduli. This system can be considered to be a model of the crystallization behavior of MG in oil, which is similar to that in many fats. Our methods are very general in the context of lipid-based foaming, in particular, from food materials, and were used in patent applications.

Rapid sphere sizing using a Bayesian analysis of reciprocal space imaging data.

Dispersed systems are important in many applications in a wide range of industries such as the petroleum, pharmaceutical and food industries. Therefore the ability to control and non-invasively measure the physical properties of these systems, such as the dispersed phase size distribution, is of significant interest, in particular for concentrated systems, where microscopy or scattering techniques may not apply or with very limited output quality. In this paper we show how reciprocal space data acquired using both 1D magnetic resonance imaging (MRI) and 2D X-ray micro-tomographic (X-ray µCT) data can be analysed, using a Bayesian statistical model, to extract the sphere size distribution (SSD) from model sphere systems and dispersed food foam samples. Glass spheres-in-xanthan gels were used as model samples with sphere diameters (D) in the range of 45µm⩽D⩽850µm. The results show that the SSD was successfully estimated from both the NMR and X-ray µCT with a good degree of accuracy for the entire range of glass spheres in times as short as two seconds. After validating the technique using model samples, the Bayesian sphere sizing method was successfully applied to air/water foam samples generated using a microfluidics apparatus with 160µm⩽D⩽400µm. The effect of different experimental parameters such as the standard deviation of the bubble size distribution and the volume fraction of the dispersed phase is discussed.

What is the risk of pyelonephritis due to desmopressin in rats with cystitis?

The risk of pyelonephritis in children with asymptomatic cystitis or bacteriuria, using desmopressin for primary nonpoliuric nocturnal enuresis, is not known. The aim of this study was to study whether there is a risk of pyelonephritis in rats with cystitis using desmopressin. Wistar rats (n = 28) were divided into four groups of cystitis (groups I-IV). DDAVP (2 microg daily) and saline (0.5 ml daily) were injected intramuscularly for 7 days in groups II and IV and groups I and III, respectively. The urinalysis, urine culture, and 24-h urinary volume (UV(24)) were assessed for all rats on days 1, 3, 5, and 7. In groups III and IV these studies were also performed on days 14, 21, and 28. Serum creatinine was determined on day 7 in all rats and on day 28 in groups III and IV. Groups I and II and groups III and IV were killed at the end of days 7 and 28, respectively. Kidneys and urinary bladders were graded subjectively for inflammation and fibrosis. Inflammation and fibrosis scores in kidney and bladder tissues were not different between DDAVP or saline-injected rats in cystitis groups at weeks 1 and 4. No fibrosis was found in any of the urinary bladders on histological examination. Ascendant pyelonephritis was detected in each of the four rats in DDAVP-administered and saline-administered cystitis groups. The histopathologic scores of the renal tissue with pyelonephritis showed no correlation with the daily urine volume, the positive test results for urine leukocyte esterase with dipstick test, the urine culture results for E. coli based on colony-forming unit per milliliter, or serum creatinine levels in cystitis groups. It was found that the administration of DDAVP to cystitis groups did not increase the risk of ascendant pyelonephritis.

Flocculation, deflocculation, and ions migration in latex suspensions.

We have studied the dynamics of the flocculation of poly(styrene-butadiene-acrylic acid) latex suspensions. These suspensions were flocculated by the addition of Ca2+ ions at high concentrations of latex particles. Using diffusing wave spectroscopy and dynamic single light scattering after dilution, we have observed--depending on the pH and on the Ca2+ concentration--several scenarios for flocculation including successive flocculation and deflocculation. This complex behavior reveals that the Ca2+ migration within the shell of the latex is slow in acidic solvent but fast in basic solvent.