Kenan Gumustekin

Importance of Anatomical Asymmetries of Transverse Sinuses: An MR Venographic Study

Time-of-flight (TOF) magnetic resonance venography (MRV) is often used to examine the intracranial dural sinuses, particularly in the evaluation of dural sinus thrombosis. The goal of the study was to evaluate the use of TOF MRV in assessing the normal anatomy of dural sinuses and their variations as sources of potential pitfalls in the diagnosis of venous sinus thrombosis. Cerebral TOF MRV obtained in 105 persons with normal MR studies were reviewed to determine the presence, aplasia and hypoplasia of the transverse sinuses. Twenty-one (20%) aplasias of the left sinus, 41 (39%) hypoplasia of the left sinus, 33 (31%) symmetric, 6 (6%) hypoplasia of the right sinus, and 4 (4%) aplasias of the right sinus cases were determined in the asymmetry in sizes of transverse sinuses. These results suggested that transverse sinus flow gaps or aplasias can be observed in approximately 24% of normal population on MR imaging. The rate of these gaps in normal subjects must be kept in mind because it can be a source of misdiagnosis in cases of suspected dural sinus thrombosis.

EFFECTS OF SLEEP DEPRIVATION, NICOTINE, AND SELENIUM ON WOUND HEALING IN RATS

Effects of sleep deprivation (SD), nicotine, and selenium (Se) on wound healing were studied in 50 male rats (Sprague-Dawley strain). Full-skin-thickness burns were produced in animals. Then, SD, nicotine, and Se administrations were applied to animals in different groups. Wound healing was assessed by pathological analysis of wound by counting fibroblasts, capillary vessels, polymorphonuclear leucocytes (PNLs), and by measuring radiolabeled immunoglobulin G (IgG) amount in wound area by radio-pharmaceutical and immunoscintigraphic procedures. The number of fibroblasts and capillary vessels were higher in control and Se groups than in sleep deprivation and nicotine groups, and the number of PNLs and the radiolabeled polyvalent IgG levels were higher in SD and nicotine groups than in control and Se groups. The results suggest that SD and nicotine may delay wound healing and that Se supplementation may accelerate wound healing by preventing nicotine-induced oxidative stress and lipid peroxidation.

Melatonin reduces oxidative stress in the rat lens due to radiation-induced oxidative injury

Purpose: The aim of this study was to evaluate the antioxidant role of melatonin against radiation-induced cataract in the rat lens after total cranial irradiation with a single 5 Gray (Gy) dose of gamma irradiation. Materials and methods: Twenty-eight Sprague-Dawley rats were used for the experiment.The rats were randomly divided into four equal groups. The control group did not receive melatonin or irradiation but received both 0.1 ml physiological saline intraperitoneally and sham irradiation. The irradiation (IR) group received 5 Gy gamma irradiation to the total cranium as a single dose plus 0.1 ml physiological saline intraperitoneally. The melatonin plus IR group received irradiation to the total cranium plus 5 mg/kg/day melatonin intraperitoneally. The melatonin group received only 5 mg/kg/day melatonin plus sham-irradiation. Biochemical parameters measured in murine lenses were carried out using spectrophotometric techniques. Results: Lens antioxidant capacity, as measured by levels of total superoxide scavenger activity (TSSA), non-enzymatic superoxide scavenger activity (NSSA) and glutathione reductase (GRD) activity, significantly increased in melatonin, control and melatonin plus IR groups when compared with the IR group. Lens glutathione-S-transferase (GST) activity significantly increased in control and melatonin groups when compared with the IR group. Lens malondialdehyde (MDA) levels significantly increased in the IR group when compared with control, melatonin and melatonin plus IR groups. Lens TSSA and NSSA activities significantly decreased in control and melatonin plus IR groups when compared with the melatonin group. Lens GST activity significantly increased in the control group when compared with melatonin plus IR group. Lens GRD activity significantly increased in melatonin and melatonin plus IR groups when compared with control group. Conclusions: Melatonin reduces oxidative stress markers and augments anti-oxidant capacity in the rat lens.

Correlation between hand preference and intraocular pressure from right- and left-eyes in right- and left-handers

To test whether there is a relationship between handedness and the intraocular pressure and there is a lateralization in the intraocular pressure, the intraocular pressures of the right- and left-eyes were compared in right- and left-handed students. The intraocular pressures were higher in the right-eye than in the left-eye in men, right-handers, and right-eyed subjects; there was no right-left difference in females, left-handers, left-eyed, and both-eyed subjects. The intraocular pressure of right- and left-eyes was higher in left-handers than right-handers. And there were significant negative correlations between hand preference and the intraocular pressure of both right- and left-eyes. We have concluded that the dominant eye has higher intraocular pressure compared to the nondominant one, and there is a relationship between hand preference and the intraocular pressure.

HANDEDNESS AND BILATERAL FEMORAL BONE DENSITIES IN MEN AND WOMEN

To examine the relation of hand preference to bilateral femoral bone mineral density (BMD), the right and left total and regional (neck, trochanter, intertrochanteric, and Wards triangle) proximal femur BMDs (g/cm2) were measured using dual-energy X-ray absorbtiometry (DEXA) in 32 right- and 26 left-handed university students. The mean total BMD of the total right-handers and the mean trochanteric BMD of the right- handed males were greater in the left femur than the right femur. Contrarily, the total left-handers had higher mean intertrochanteric BMD in the right side than in the left side. There were negative correlations between R-L BMD differences and Geschwind scores of total, male, and female subjects. The results suggest that femur-BMD may be related to hand preference.

Relations among Hand Preference, Craniofacial Asymmetry, and Ear Advantage in Young Subjects

The relations for hand preference with craniofacial asymmetry and ear advantage, and between craniofacial asymmetry and ear advantage were investigated in young healthy subjects. Ear advantage was recorded as duration of hearing, craniofacial asymmetry by computerized tomography in 44 right-handed and 38 left-handed male and female high school students. Right-handers had a right ear advantage and a larger left craniofacial region, whereas left-handers had a left ear advantage and a larger right craniofacial region. These results are consistent with the speculation that hand preference may be related to craniofacial and consequently aural asymmetries.

CELL-MEDIATED IMMUNE HYPERSENSITIVITY IS STRONGER IN THE LEFT SIDE OF THE BODY THAN THE RIGHT IN HEALTHY YOUNG SUBJECTS

More frequent appearance of herpes zoster infection on the left side of the body has been noted. In women, breast cancer occurs more frequently on the left side. It has been suggested that the left neocortex is involved in neuroimmunomodulation via the dopaminergic system. In this study, our purpose was to investigate the possible difference in cell-mediated hypersensitivity between right and left body sides using the tuberculin test with 22 male and 36 female healthy high school students. In the present study, the cell-mediated hypersensitivity was higher in the left side of the body than the right. This difference was slightly more apparent in the girls and may be related to brain asymmetry in neuroimmunomodulation.

Vitamin E but not Hippophea rhamnoides L. prevented nicotine-induced oxidative stress in rat brain.

Oxidant effects of nicotine in the central nervous system is not clear. The aim of this study was to investigate whether nicotine induces oxidative stress in rat brain, and if it does, to test the effects of Hippophea rhamnoides L. extract (HRe-1) and also vitamin E as a positive control. The groups were: nicotine [0.5 mg/kg/day, intraperitoneal (i.p.)]; nicotine-vitamin E [75 mg/kg/day, intragastric (i.g.)]; nicotine-HRe-1 (250 mg/kg/day, i.g.); and control group (receiving only vehicles). There were eight rats per group and supplementation period was 3 weeks. Malondialdehyde (MDA) level was increased by nicotine in brain tissue, which was prevented by vitamin E whereas not affected by HRe-1. Brain tissue glutathione S-transferase activities of nicotine administered and HRe-1 supplemented groups were lower than control and vitamin E supplemented groups, while glutathione peroxidase (GSH-Px) activities of vitamin E and HRe-1 supplemented groups were lower than the nicotine administered group. Superoxide dismutase activity was not affected by any of the treatments. Total glutathione level was higher in the vitamin E supplemented group compared with control and nicotine administered groups. Vitamin E might have easily diffused to rat brain as a lipid soluble antioxidant, however, the plant extract, HRe-1, would not have sufficiently diffused to the brain to exert its antioxidant effect.

Left Ear (Right Temporal Hemisphere) Advantage and Left Temporal Hemispheric Dysfunction in Schizophrenia

In this study, to investigate the right or left ear advantages in psychiatric patients, the durations of hearing for right and left ears were assessed in 61 psychiatric patients, 26 with schizophrenia, 17 with depressive disorder, 13 with bipolar affective disorder, and 5 with brief psychotic disorder, plus 24 controls. Diagnoses were made on the basis of information provided from clinical interviews and the Structured Clinical Interview for DSM-IV (SCID). Schizophrenia was associated with a left ear advantage, and both depressive disorder and brief psychotic disorder were associated with right ear advantage as well as controls. These results suggest that their schizophrenia may be associated with a left temporal lobe dysfunction.

Effects of nicotine and Vitamin E on Carbonic anhydrase activity in some rat tissues In Vivo and In Vitro

Effects of nicotine, nicotine+vitamin E and nicotine+Hippophea rhamnoides L. extract (HRe-1) on muscle, heart, lungs, testicle, kidney, stomach, brain and liver carbonic anhydrase (CA; EC 4.2.1.1.) enzyme activities were investigated in vivo. Groups of rats were given nicotine (0.5 mg/kg/day, i.p.), nicotine+vitamin E (75 mg/kg/day, i.g.), nicotine+HRe-1 (250 mg/kg/day, i.g.) and a control group vehicle only. The results showed that nicotine inhibited the heart, lung, stomach and liver CA enzyme activities by ∼80% (p < 0.001), ∼94% (p < 0.001), ∼47% (p < 0.001) and ∼81% (p < 0.001) respectively, and activated muscle and kidney, but had no effects on the testicle and brain CA activities. Nicotine+vitamin E inhibited the heart and liver CA enzyme activities by ∼50% (p < 0.001), and ∼50% (p < 0.001), respectively, and nicotine+vitamin E activated the muscle CA activity. However, nicotine+vitamin E had no effect on lung, testicle, kidney, stomach and brain CA activities. Nicotine+HRe-1 inhibited the heart and stomach CA enzyme activities by ∼51% (p < 0.001), and ∼32% (p < 0.002), respectively, and activated the muscle and brain CA activities, but had no effects on the lung, testicle, kidney, and liver CA activities. In vitro CA inhibition results for similar experiments correlated well with the in vivo experimental results in lungs, testicles, kidney, stomach, brain and liver tissues.