Geometric morphometric study of anterior branches of external carotid artery and carotid bifurcation by 3D-CT angiography.

PURPOSE: The aim of our study was to determine the variations of the anterior branches of the external carotid artery (ECA) and investigate the morphometric and geometric features of the anterior branches of the ECA and carotid bifurcation (CB). METHODS: A total of 563 ECAs were included from 288 patients in the study. Classification and exit angles of anterior branches of ECA and determination of vertebral levels of CB and anterior branches were performed. RESULTS: The anterior branch variants of the ECA were observed in 8 different subgroups. The most common variations were type Ia 42.3% (n = 120) on the right and type Ib 40.9% (n = 114) on the left. When looking at the vertebral levels, CB was detected at C4 level in 32.9% of total ECAs (n = 185), STA was at C4 level in 33.4% of total ECAs (n = 188), LA was at C3 level in 50.1% of total ECAs (n = 282), and FA was at C2 level in 37.3% of total ECAs. The mean CB angle in all cases was 59.93° ± 16.04. In the anterior branches of the ECA in cases belonging to the Type I group, the widest angle belonged to FA (R = 116.88 ± 27.04°, L = 110.32° ± 25.94). CONCLUSION: In conclusion, a new classification of the variations of the anterior branches of the ECA was made on the basis of the CTA images to gain more practicality in surgical procedures. This study revealed for the first time the angular and level relationship between CB and ECA anterior branches.

Neuroprotective effects of melatonin administered alone or in combination with topiramate in neonatal hypoxic-ischemic rat model.

PURPOSE: The objective of this study was to compare the effects of two neuroprotective agents; melatonin, a free radical scavenger and topiramate, AMPA/kainate receptor antagonist, administered alone or in combination in neonatal hypoxic-ischemic model. METHODS: After being anesthetized, 7-day-old pups underwent ischemia followed by exposure to hypoxia. The pups were divided into 4 groups in order to receive the vehicle, melatonin, topiramate and combination of topiramate and melatonin. These were administered intraperitoneally for three times; the first before ischemia, the second after hypoxia and the third 24 hours after the second dose. After sacrification, infarct volume and apoptosis were evaluated. RESULTS: Percent infarcted brain volume was significantly reduced in rats which received drugs compared with those which received the vehicle. The number of TUNEL positive cells per unit area in hippocampus and cortex were markedly reduced in drug treated groups compared with control group. No significant differences were found regarding percent infarcted brain volume and number of TUNEL positive cells among drug-treated groups. CONCLUSIONS: Melatonin and topiramate, administered either alone or in combination significantly reduced the percent infarcted brain volume and number of TUNEL positive cells suggesting that these agents may confer benefit in treatment of infants with hypoxic-ischemic encephalopathy.

Possible neuroprotective effects of magnesium sulfate and melatonin as both pre- and post-treatment in a neonatal hypoxic-ischemic rat model.

BACKGROUND: Perinatal hypoxia-ischemia is a major cause of mortality and long-term neurological deficits. OBJECTIVES: The objective of this study was to compare the effects of two neuroprotective agents; magnesium sulfate and melatonin, administered alone or in combination, on brain infarct volume and TUNEL positivity in a neonatal hypoxic-ischemic (HI) rat model. METHODS: After being anesthetized, 7-day-old pups (n = 80) underwent ischemia followed by exposure to hypoxia for 2 h. The pups were then divided equally and randomly into 4 groups in order to receive the vehicle (saline, control group), magnesium sulfate, melatonin or a combination of magnesium sulfate and melatonin. Treatments were administered intraperitoneally three times; the first being just before ischemia, the second after hypoxia and the third 24 h after the second dose. The pups were sacrificed on postnatal day 10, their brains harvested and evaluated for infarct volume and neuronal apoptosis. RESULTS: Percent infarcted brain volume was significantly reduced in pups receiving the drugs (either magnesium sulfate, melatonin or their combination) compared with those receiving the vehicle. In addition, TUNEL staining showed markedly reduced numbers of TUNEL-positive cells per unit area in the CA1, CA3 and dentate gyrus regions of the hippocampus and in the cortex. However, no statistically significant differences were found regarding percent infarcted brain volume and number of TUNEL-positive cells among the drug-treated groups. CONCLUSIONS: Magnesium sulfate and melatonin, two agents acting at different stages of HI brain damage, administered either alone or in combination, significantly reduced the percent infarcted brain volume and TUNEL positivity, suggesting that these agents may confer a possible benefit in the treatment of infants with HI encephalopathy.

Effects of extremely low-frequency magnetic field on caspase activities and oxidative stress values in rat brain.

This study was aimed to investigate the effect of extremely low-frequency magnetic field (ELF-MF) on apoptosis and oxidative stress values in the brain of rat. Rats were exposed to 100 and 500 µT ELF-MF, which are the safety standards of public and occupational exposure for 2 h/day for 10 months. Brain tissues were immunohistochemically stained for the active (cleaved) caspase-3 in order to measure the apoptotic index by a semi-quantitative scoring system. In addition, the levels of catalase (CAT), malondialdehyde (MDA), myeloperoxidase (MPO), total antioxidative capacity (TAC), total oxidant status (TOS), and oxidative stress index (OSI) were measured in rat brain. Final score of apoptosis and MPO activity were not significantly different between the groups. CAT activity decreased in both exposure groups (p < 0.05), while TAC was found to be lower in ELF 500 group than those in ELF-100 and sham groups (p < 0.05). MDA, TOS, and OSI values were found to be higher in ELF-500 group than those in ELF-100 and sham groups (p < 0.05). In conclusion, apoptosis was not changed by long-term ELF-MF exposure, while both 100 and 500 µT ELF-MF exposure induced toxic effect in the rat brain by increasing oxidative stress and diminishing antioxidant defense system.

The peri-microvascular edema in hippocampal CA1 area in a rat model of sepsis.

Encephalopathy is a common complication of sepsis. However, little is known about the morphological changes that occur in the brain during sepsis. In this study, fecal peritonitis was induced in Wistar rats, which had been monitored for 4 h before their brains were removed and samples from the CA1 area taken. In addition to higher blood pressure with a decreasing pattern and a significant drop in rectal temperature, an increased heart rate and marked respiratory failure were observed. The tissue was investigated and compared with corresponding hippocampal samples taken from sham-operated and not operated control groups. Significantly more peri-microvascular edema was found in the hippocampal CA1 area in the septic group. The percentages of the peri-microvascular edema were 158.57 +/- 3.6%, 122.84 +/- 1.5% and 120.24 +/- 1.9% in the fecal peritonitis group, sham-operated and not operated control groups, respectively. The results may suggest that the edema observed around the microvessels may participate in the pathogenesis of the septic encephalopathy probably by causing in the microvascular permeability characteristics.

The localization and anthropometry of mental foramen on late Byzantine mandibles.

Comprehensive studies of the human skeletal features and variations between and within populations are beneficial both for clinical applications and determination of racial characteristics of populations. The aim of this study was to examine the location and anthropometric characteristics of the mental foramen in 36 adult male mandibles of the Late Byzantine period. The results demonstrated that the most common position of the mental foramen was in line with the longitudinal axis of the second premolar (50% right side; 47% left side) followed by a location between the first and second premolars (33% right side; 36% left side). When compared with the results of previous similar studies, the results obtained in the present study suggest that traits such as the localization of mental foramen may not only differ between populations of different geographic environment but also within the inhabitants of the same geography.