Pinar Akan

Alterations in BDNF (brain derived neurotrophic factor) and GDNF (glial cell line-derived neurotrophic factor) serum levels in bipolar disorder: The role of lithium

OBJECTIVE Brain-derived neurotrophic factor (BDNF) has been consistently reported to be decreased in mania or depression in bipolar disorders. Evidence suggests that Glial cell line-derived neurotrophic factor (GDNF) has a role in the pathogenesis of mood disorders. Whether GDNF and BDNF act in the same way across different episodes in bipolar disorders is unclear. METHOD BDNF and GDNF serum levels were measured simultaneously by enzyme-linked immunosorbent assay (ELISA) method in 96 patients diagnosed with bipolar disorder according to DSM-IV (37 euthymic, 33 manic, 26 depressed) in comparison to 61 healthy volunteers. SCID- I and SCID-non patient version were used for clinical evaluation of the patients and healthy volunteers respectively. Correlations between the two trophic factor levels, and medication dose, duration and serum levels of lithium or valproate were studied across different episodes of illness. RESULTS Patients had significantly lower BDNF levels during mania and depression compared to euthymic patients and healthy controls. GDNF levels were not distinctive. However GDNF/BDNF ratio was higher in manic state compared to euthymia and healthy controls. Significant negative correlation was observed between BDNF and GDNF levels in euthymic patients. While BDNF levels correlated positively, GDNF levels correlated negatively with lithium levels. Regression analysis confirmed that lithium levels predicted only GDNF levels positively in mania, and negatively in euthymia. LIMITATIONS Small sample size in different episodes and drug-free patients was the limitation of thestudy. CONCLUSION Current data suggests that lithium exerts its therapeutic action by an inverse effect on BDNF and GDNF levels, possibly by up-regulating BDNF and down-regulating GDNF to achieve euthymia.

Influences of Acute and Chronic Aerobic Exercise on the Plasma Homocysteine Level

Background and Aims: Elevated plasma homocysteine (PH) levels have been identified as a risk factor for cardiovascular diseases. The aims of this study were to investigate the influences of submaximal acute aerobic exercise and aerobic training on PH levels and lipid profiles. Methods: 69 volunteersubjects (21.12 ± 2.08 years) were randomized to three groups as acute, training and control groups. Examination and blood samples were collected before and immediately after exercise in the acute group and before and 6 weeks later in the training and control groups. Results: A significant increase in PH concentration was recorded immediately after aerobic exercise, compared with baseline values (p = 0.001). Although, in the training group, total cholesterol (p = 0.00) and LDL cholesterol (p = 0.001) decreased significantly after training, no significant changes in PH concentration, HDL cholesterol (p = 0.087) and triglyceride (p = 194) levels were found. Conclusions: It can be said that the PH level increases following submaximal acute aerobic exercise, but does not alter after submaximal aerobic training due to training duration or intensity. Therefore, submaximal aerobic training decreases lipid profiles independent of the PH level.

Pregnenolone protects the PC-12 cell line against amyloid beta peptide toxicity but its sulfate ester does not

Pregnenolone (P), the main precursor of the steroids, and its sulfate ester, pregnenolone sulfate (PS), are the major neurosteroids produced in the neural tissue. Many neuroendocrinological studies stressed the neuroprotective role of neurosteroids although it has been suggested that the inhibition of P and PS synthesis can delay neuronal cell death. The potential roles of P and PS in vital neuronal functions and in amyloid beta peptide (Abeta) toxicity are not clearly identified. This work aims to investigate the effects of P and PS on cell viability and Abeta peptide toxicity in a concentration and exposure time-dependent manner in rat PC-12 cells. The cells were treated with 20muM Abeta peptide 25-35 and variable concentrations of P and PS ranging from 0.5muM to 100muM. To examine the effects of steroid treatment on Abeta peptide toxicity, 0.5muM (low) and 50muM (high) neurosteroids were used. The cell viability and lactate dehydrogenase release of cells were evaluated after 24, 48 and 72h. Morphological changes of cells were also examined. The treatment with higher than 1muM concentrations of P and PS significantly decreased the cell viability comparing to untreated cells. At lower concentrations, P and PS had no toxic actions until 72h. The Abeta treatment resulted in a significant decrease in cell viability comparing to untreated cells. P showed a dose-dependent protective effect against Abeta peptide in PC-12 cells. But its sulfate ester did not have the same effect on Abeta peptide toxicity, even it significantly decreased cell viability in Abeta-treated cells. Consequently, the discrepant effects of P and PS on Abeta peptide toxicity may provide insight on the pathogenesis of Alzheimers disease.

Effects of N-acetylcysteine on radiocontrast nephropathy in rats

Objective. N-acetylcysteine (NAC) has yielded some promising results recently in the prevention of radiocontrast nephropathy (RCN). In this study, the structural and functional effects of NAC on RCN were analyzed. Material and methods. Twenty-eight Wistar rats were randomized into four groups, as follows: Group 1, controls; Group 2, contrast; Group 3, contrast + NAC; and Group 4, NAC. All rats were deprived of water for 24 h and then contrast medium (ioxoglate; 10 ml/kg) was administered to Groups 2 and 3. NAC (50 mg/kg) was introduced enterally to Groups 3 and 4 at a dose of 50 mg/kg in 0.5 ml of distilled water, in four sequential doses 12 h apart, starting after 12 h of water deprivation. After 4 days, rats were sacrificed. Creatinine clearance was calculated. The malondialdehyde (MDA) level was quantified in tissue samples. Slides stained with hematoxylin–eosin and periodic acid–Schiff were examined by means of light microscopy. Each tubular cross-section from all images was scored as either mild (preserved brush border, no necrosis), moderate (loss of brush border, no necrosis) or severe (loss of brush border accompanied by necrosis) and the frequencies of these lesion severities were compared. Results. Mean baseline serum creatinine levels and creatinine clearances were similar in all groups. Mean serum creatinine level increased significantly only in Group 2 (0.6±0.1 vs 0.7±0.2 mg/dl; p<0.05). Tissue MDA levels were similar in all groups. Moderate (13.8%±1.5% vs 42%±1.4%; p<0.05) and severe (0% vs 40%±2.1%; p<0.05) lesions were significantly more frequent in Group 2 compared to Group 1. The frequency of severe lesions in Group 3 was found to be halved compared to that in Group 1 (40%±2.1% vs 20.2%±0.86%; p<0.05). Conclusion. NAC protects the kidneys following exposure to contrast medium as it decreased the severity of tubular lesions in rats.

New generation IQ-200 automated urine microscopy analyzer compared with KOVA cell chamber.

Objective: The examination of the urine remains to be one of the most commonly performed tests in laboratory practice. Currently, laboratories also need to accredit their urine diagnostics by comparing their measurement methods to acceptable references. In this study we compared particle counts obtained by new generation automated technique, image capture analysis (IQ‐200) with those of a standardized chamber counts. Design and Methods: The same 258 urine samples from different departments of a hospital assayed by IQ‐200 were analyzed in parallel with the KOVA cell chamber system. Clinically significant discrepancy results (positive vs. negative) for red blood cell (RBC) and white blood cell (WBC) were also compared with those obtained by dipstick testing. Results: There was a good agreement between the automated system and sediment microscopy for RBCs, WBCs, and squamous epithelial cells (SCs) (r=0.90; r=0.80; r=0.72, respectively: P<0.001). The IQ‐200 was more sensitive for determining RBCs, WBCs, and SCs than other formed elements. Conclusions: IQ‐200 can perform accurate quantification of microscopic element in urine. However, automated techniques are not completely free of error. Therefore, by adopting an appropriate algorithm and combining the results with stript analysis and other laboratory tests allows further reduction of clinically important errors. J. Clin. Lab. Anal. 24:67–71, 2010.  © 2010 Wiley‐Liss, Inc.

Do serum BDNF levels vary in self-harm behavior among adolescents and are they correlated with traumatic experiences?

The aim of this study was to compare serum brain-derived neurotrophic factor (BDNF) levels between adolescents that harm themselves, those that receive psychiatric treatment but do not harm themselves, healthy adolescents, and childhood traumas and to investigate the relationship between traumatic experiences and serum BDNF levels. The cases were divided into two groups of 40 adolescents exhibiting self-harm behavior (self-harm/diagnosed group) and 30 adolescents receiving psychiatric treatment but not exhibiting self-harm behaviors (non self-harm/diagnosed group). The control group (healthy control group) consisted of 35 healthy adolescents with no psychiatric disorders or self-harm behaviors. The adolescents were asked to fill in the Inventory of Statements About Self Injury (ISAS) and Childhood Trauma Questionnaire (CTQ). For BDNF measurement, blood samples were taken from the cases and controls. The serum BDNF level of self-harming adolescents who used the self-cutting method was significantly lower than that of other groups, and serum BDNF levels decreased with the increase in the emotional neglect and abuse severity of self-harming adolescents during childhood. In our study, serum BDNF levels decreased with the increase in emotional abuse in self-harming adolescents. This finding may indicate that neuroplasticity can be affected by a negative emotional environment during the early period.

Comparison of macular pigment optical density in patients with dry and wet age-related macular degeneration

Aim: The aim of the study was to evaluate the macular pigment optical density (MPOD) levels in patients with wet age-related macular degeneration (AMD), dry AMD, and also in healthy controls. Settings and Design: This study was conducted at Department of Ophthalmology, and the study design was a prospective study. Patients and Methods: Forty-eight patients with wet AMD, 51 patients with dry AMD, and 50 controls were included in the study. All patients were naive to both previous lutein or zeaxanthin administration and any previous intravitreal injections. Fundus reflectance (VISUCAM 500, reflectance of a single 460 nm wavelength) was used to measure the MPOD levels. Three groups were compared regarding age, gender, serum lutein, and zeaxanthin concentrations as well as MPOD levels. Results: Serum lutein and zeaxanthin levels were significantly higher in control group when compared with wet AMD (Group 1) and dry AMD (Group 2) (P = 0.001 and P< 0.001, respectively). Mean MPOD was found to be similar in all of the three study subgroups (P = 0.630). However, maximum MPOD was significantly higher in control group when compared with Group 1 and 2 (P = 0.003). There was no correlation between serum lutein or zeaxanthin concentrations and mean MPOD levels (P = 0.815, r = 0.014 and P = 0.461, r = 0.043, respectively), but there was a weak correlation between serum zeaxanthin concentration and maximum MPOD level (P = 0.042, r = 0.124). Maximum MPOD level was found to be correlated with the level of AMD (Group 1, 2, and 3; r = 0.184, P = 0.041). Conclusion: Maximum MPOD level was found to be lower in patients with AMD when compared with control cases. Mean MPOD and maximum MPOD levels were similar in wet and dry AMD Groups. These results can be applied clinically keeping in mind that MPOD measurements with one wavelength reflectometry may not be completely reliable.

Excessively High Urinary Beta 2-Microglobulin Level: A Sign of Pathology or Laboratory Error ?

Measurement of urinary β2M (beta 2-microglobulin) is a sensitive and reliable assay for detecting tubular injury, renal toxicity, lymphomas, leukemia, or myeloma. Some chemical substrates may increase the level of β2M in-vivo. Elevated β2M level in urine is unusual because it rapidly degrades when pH is below 6. The level of β2M in the bladder can also be used as a marker to assess renal tubular maturation in neonates. β2M in the bladder could be a result of fetal megacystis, which is an abnormally enlarged bladder appearing after 10 weeks of gestation, when the fetus begins to produce urine. Identification of the pregnant women instead of the fetus is a common pre-analytical error with samples sent from the gynecology clinic to the laboratory. Here we present the case of a 24-year-old pregnant woman whose urine analysis results indicated excessively high β2M level in the urine. The present study could improve the understanding of urinary β2M analysis, laboratory errors, and the interpretation of test results.

Effect of Day and Night Desflurane Anaesthesia on Melatonin Levels in Rats

OBJECTIVE The aim of this study is to investigate the effect of day and night administration of desflurane anaesthesia on melatonin levels in rats. METHODS Twenty-four 15-day-old rats were included in the study and were divided into four groups. The rats were anaesthetised between 19:00-01:00 (night group) and 07:00-13:00 (day group) with 5.7% desflurane concentration in 6 L min-1 100% oxygen. 6 L min-1 oxygen was administered to the control groups. At the end of 6 h of anaesthesia, blood samples were taken, and rats were sacrificed. Blood samples were centrifuged and melatonin levels from plasma samples were measured with radioimmunoassay. RESULTS There was a statistically significant difference between the groups (p=0.007). Between group day control and group night control there was a statistically significant difference (p=0.042). Further, there was a significant difference between group day control and night desfluran as well (p=0.024). We could not find any difference between other groups. CONCLUSION This study showed that 6 hours of 5.7% desflurane anaesthesia during day and night hours did not significantly change melatonin levels.

Day and Night Administration of Sevoflurane Effect of Melatonin Levels in Rats

Use of general anesthesia to prematures and young children is a part of modern anesthesiology. General anesthetics are usually considered safe, however some recent animal studies allude to anesthetic agents may be harming the immature developing brain. It has been recently shown that frequently used general anesthetics such as benzodiazepines, barbiturates, ketamine, isoflurane and nitrous oxide exposure of the immature rat brain, may cause massive neuronal death [1].