Aortic and iliac fixation of seven endografts for abdominal-aortic aneurysm repair in an experimental model using human cadaveric aortas.

OBJECTIVE: To evaluate the proximal and distal (iliac) fixation of seven self-expanding endografts, used in the endovascular treatment (EVAR) of abdominal-aortic aneurysm (AAA), by measuring the displacement force (DF) necessary to dislocate the devices from their fixation sites. METHODS: A total of 20 human cadaveric aortas were exposed, left in situ and transected to serve as fixation zones. The Anaconda, EndoFit aorto-uni-iliac, Endurant, Powerlink, Excluder, Talent and Zenith stent grafts were deployed and caudal force was applied at the flow divider, through a force gauge. The DF needed to dislocate each device ≥ 20 mm from the infrarenal neck was recorded before and after moulding-balloon dilatation. Cephalad force was similarly applied to each iliac limb to assess distal fixation before and after moulding-balloon dilatation. RESULTS: Endografts with fixation hooks or barbs displayed a significantly higher DF necessary to dislocate the proximal portion compared with devices with no such fixation modalities (p < 0.001). Balloon dilatation produced a significant increase in DF in both devices with (p < 0.001) or without (p = 0.003) hooks or barbs. Suprarenal support did not enhance proximal fixation (p = 0.90). Balloon dilatation significantly increased the DF necessary to dislodge the iliac limbs (p = 0.007). CONCLUSIONS: Devices with fixation hooks displayed higher proximal fixation. Moulding-balloon dilatation increased proximal and distal fixation. Suprarenal support did not affect proximal fixation.

Acute paraplegia in painless aortic dissection. Rich imaging with poor outcome.

STUDY DESIGN: Case report. OBJECTIVE: To describe the clinical and imaging findings of a patient with painless aortic dissection. SETTING: University Neurology Department, Thessaloniki, Greece. PATIENT, METHODS, RESULTS: A 46-year-old man was transferred to our Department for emergent evaluation of paraplegia, from the local hospital of the nearby town, where he was admitted complaining from sudden, painless, bilateral leg weakness, 24 h earlier. He presented complete flaccid paraplegia with urinary retention, loss of pain and temperature sensation below the TH7 level and well-preserved vibration and position sense bilaterally. He had no pain and general physical examination was unremarkable. Chest X-rays first raised the suspicion of an aortic lesion. Thoracic MRI revealed cord dilation, with no enhancement on T1-weighted images (wi) and increased signal on T2-wi at the TH9-TH12 levels, suggesting cord ischemia. At the same MR sequences, the double lumen of the descending aorta indicated dissection in both sagittal and axial images. Later the same day, the patient died, and autopsy verified dissection of the descending aorta up to the aortic valve. CONCLUSION: The rapid evolution of our case further points out that radiologists, neurologists, as well as internal specialists should be vigilant for this emergency, which despite rich imaging could have a fatal outcome.

The combination of silver techniques for studying the pathology of Alzheimer's disease.

Alzheimer's diseaseis a progressive neurodegenerative disorder, which implicates the whole central nervous system. The hallmarks of the disease are the development of neuritic plaques and neurofibrillary tangles, the accumulation of beta-amyloid in the cytoplasm of the neurons (soluble beta-amyloid oligomers) and the neuropile space (insoluble amyloidal fibrils), the neuronal loss, and the devastating synaptic alterations. Despite the fact that for the identification of the plaques and tangles and for the detection of the amyloid deposits and the neuronal loss, there are specific techniques even in light microscopy, synaptic pathology can be studied only with electron microscopy or indirectly with immunohistochemistry, because several alterations in the density of proteins located in synaptic junction (drebrin, synapsin, synaptophisin) may be occurring. Thus, this article presents original Nauta method impregnating degenerating axons as well as axonic terminals in post-mortem material derived from patients suffering from Alzheimer's disease. Furthermore, the article proposes its application in combination with Golgi method and Gallyas technique for a spheroid view of the neuronal degeneration and synaptic pathology in the study of any brain region in Alzheimer's disease.

Reelin immunoreactivity and morphological analysis of the human visual cortex.

Reelin is a secreted glycoprotein with a crucial role in development of the Central Nervous System. In adults, its function remains unclear but it may be involved in the modulation of synaptic plasticity. Having in mind this possible property of reelin, the authors decided to study the distribution of reelin immunoreactivity in the neurons of the human adult primary visual cortex and compare the findings with morphological analysis (Golgi method) of neuronal networks. The distribution of reelin in the primary visual cortex is different from other cortical area examined; reelin is mostly present in the neurons of second and sixth layer.

Headspace solid phase microextraction for the gas chromatographic analysis of methyl-parathion in post-mortem human samples. Application in a suicide case by intravenous injection.

A simple and rapid procedure for the determination of methyl-parathion (m-p) in post-mortem biological samples was developed using headspace solid phase microextraction (SPME) and gas chromatography (GC) with nitrogen-phosphorous detection (NPD). Methyl-parathion was extracted on 85 microm polyacrylate SPME fiber. Salt addition, extraction temperature, and extraction time were optimized to enhance the sensitivity of the method. The linearity (y = 0.0473x - 0.0113, R2 = 0.9992) and the dynamic range (0.1-40 microg/ml) were found very satisfactory. The recoveries of methyl-parathion were found to be 46% in spiked human whole blood, 53% in spiked homogenized liver tissue, and 54% in spiked homogenized kidney tissue compared with samples prepared in water. The coefficients of variations for 2, 4, and 20 microg/ml of methyl-parathion in blood ranged from 0.9 to 5.1%, whereas the detection limit of the method was satisfactory (1 ng/ml in aqueous samples, 50 ng/ml in whole blood). The developed procedure was applied to post-mortem biological samples from a 21-year-old woman fatally poisoned (suicide) by intravenous injection of methyl-parathion. The intact insecticide was found in the post-mortem blood at a concentration of 24 microg/ml. No methyl-parathion was detected in the liver, kidneys, and gastric contents.

Amphetamine derivative related deaths in northern Greece.

Until 1997, only one amphetamine related derivatives (AMPs) fatality had been reported in Greece. Since then, amphetamine (AMP) or AMPs have been found in seven out of 1,500 post-mortem toxicological cases. The cause and manner of death of these seven cases were: 3,4-methylenedioxy-N-methamphetamine (MDMA) and 3,4-methylenedioxy-N-ethylamphetamine (MDEA) poisoning (n = 1), drowning in water (n = 4), cranial injuries caused by a traffic accident (n = 1) and heart failure (n = 1). In the case where the use of AMP or AMPs was considered, the immediate cause of death post-mortem toxicological analysis revealed 2 microg/ml MDMA and 0.7 microg/ml MDEA in blood. MDMA was identified in two cases of drowning (2 microg/ml in blood in the first case and 1.7 microg/g in liver in the second case) and in the traffic accident case (0.4 microg/g in liver). Methamphetamine was detected in two cases of drowning (2.5 microg/ml in blood in the first case and 6 microg/g in liver in the second case). AMP was found in the heart failure case (0.2 microg/g in liver). Alcohol was present, together with AMP or AMPs, in four cases. These findings indicate an increase in the illegal abuse of AMPs in Greece. Because of this, we now routinely screen for AMPs.

Evaluation of the addiction history of a dead woman after exhumation and sectional hair testing.

In Greece, sectional hair analysis, in addition to clinical examination, has been used as a valuable tool for the confirmation of a person's history of drug use. The present report concerns the toxicologic analysis of the exhumed remains and hair samples of an 18-year-old woman. Postmortem toxicologic analysis of blood and urine confirmed recent opiate and cannabis use and indicated that death was associated with heroin abuse. Several months later, the woman's family asked for exhumation and reexamination of the body, insisting that the cause of death was homicide. The investigating judge ordered exhumation and new medicolegal examination of the body. The investigation of the drug profile along the hair shaft was undertaken by analyzing hair sections 1 cm from the hair root for morphine, 6-monoacetylmorphine, heroin, and cannabinoids. The total lengths of the hair samples ranged from 8 to 11 cm. The total morphine levels in the hair sections corresponding to the 3-month period before death were significantly lower (1.5-2.85 ng/mg) than those of the 4- to 10-month period before death (7.4-14.8 ng/mg). An interpretation of these results may be occasional drug use (with considerable attenuation of use during the last 3 months before death). Decrease of tolerance to heroin caused by abstinence and relapse in use could have been the cause of death.

The nucleus basalis of Meynert of the human brain: a Golgi and electron microscope study.

The nucleus basalis of Meynert of normal brains, aged from 15 to 73 years was studied in Golgi preparations and in electron microscopy. The nucleus is composed of large triangular, polyhedral and bipolar cells which are intermixed with numerous small or medium-sized spiny neurons. All of the neurons form a dense three dimensional dendritic arborization, with numerous secondary and tertiary dendritic branches studded with spines. The ultrastructural analysis revealed numerous axodendritic and axosomatic synapses between the spines. The ultrastructural analysis revealed numerous axodendritic and axosomatic synapses between the spiny neurons and the large triangular and polyhedral neurons. The presynaptic axonic profiles are plenty of ellipsoid and round synaptic vesicles. Large presynaptic terminals are seen frequently surrounded by numerous dendritic spines forming synaptic glomeruli, in all the areas of the nucleus basalis of Meynert. An age depended decrease of the number of neurons was noticed affecting mainly the population of the spiny neurons. Although in senile and presenile dementias an impressive loss of the cholinergic neurons of the nucleus basalis was reported, in normal aging the large cholinergic neurons of the nucleus basalis seems to be intact, whereas the medium and small shaped spiny neurons are decreased in number suggesting that the GABA-ergic neurons are principally affected.

Magnesium, calcium and zinc fluctuations on skin induced injuries in correlation with time of induction.

In the present study, fluctuations of trace elements Mg, Ca and Zn concentrations with time on skin-induced injuries was investigated. To accomplish this, 144 animals (pig) aged between 5-6 months scheduled for food provision process (slaughter) were used. At the gluteus area, injuries were induced prior to slaughter at intervals of 30 s, 30 min, 1, 2, 4, 8 h. Local anaesthesia and cold therapy for prompt relief of pain (ethylchloride, C2H5Cl) was applied. Postmortem tissue excision in and around the injured site was promptly performed. The tissue obtained was segmented into three zones of equal distances (2 cm) in between and weighed 3 g wet weight. Tissue specimens were analysed by atomic absorption spectroscopy for the three elements. The results were correlated with time of injury. Suggestive alterations in trace elements mean concentrations with time were confirmed. The ratios of the mean in twos (Ca/Zn, Ca/Mg, Mg/Zn) versus time were graphed. Effectively, the curves achieved by analysing postmortem tissues, serve to estimate the time of an injury induced in vivo.