Ultrastructural changes in the circumventricular organs after experimental subarachnoid hemorrhage

OBJECTIVES: Circumventricular organs (CVOs) are fine, periventricular, neurotransmitter-rich structures that are devoid of a blood-brain barrier and are known for their secretory role controlling fluid and electrolyte balance, thirst and even reproduction. Common pathologies of the brain such as trauma or bleeding affect CVOs, and hence their function. However, at what stage of these disease processes are CVOs affected and the time sequence of their recovery is still not clear. The aim of this study was to detect the morphological changes in CVOs using electron microscopy after experimental subarachnoid hemorrhage (SAH).METHODS: Experimental SAH was induced by transclival puncture of the basilar artery. Both scanning and transmission electron microscopic examination of the representive sections from each CVO was undertaken.RESULTS: Electron microscopy has shown that after SAH, the cells that form the CVOs exhibit signs of cellular necrosis with margination of the nucleus as well as cytoplasmic, mitochondrial and axonal edema. The subfornicial organ and organum vasculosum lamina terminalis appear to be more vulnerable to the effects of SAH than the median eminence or area postrema.DISCUSSION: Considering the fact that the experimental SAH model we have used is very similar to the momentary rupture of an aneurysm with secondary reflex spasm to seal the hole, it will not be unrealistic to consider that similar effects may also take place in the clinical setting.     

Malignant cerebral infarction secondary to internal carotid injury in closed head trauma: good outcome with aggressive treatment--a case report

A 25-year-old male patient in whom occlusion of the internal carotid artery developed secondary to a skull base fracture is presented. The diagnosis of internal carotid artery occlusion was reached 12 hours after the admission and 17 hours after the injury. The patient was initially treated for ischemic edema and when the patient showed signs of cerebral herniation, decompressive craniectomy was necessary. The outcome was good. The clinical and radiologic characteristics of internal carotid artery occlusion in closed head injury are highlighted and treatment options are reviewed in light of pertinent literature.     

Clinical approach to graft hepatic artery thrombosis following living related liver transplantation

Hepatic artery thrombosis (HAT) has an occurrence rate of 1.7-26% following living donor liver transplantation (LDLT) and is one of the most common reasons for graft loss and mortality in this population. There is a higher incidence of HAT in pediatric recipients. The aim of this case report is to discuss clinical approaches for the treatment of HAT occurring in the early post-operative period after LDLT. An 11-month-old, 7.8-kg female with cirrhosis secondary to biliary atresia underwent LDLT at Gazi University Hospital in Ankara. The graft was a left lateral segment from her father with a left hepatic artery (HA) of 2 mm diameter and a graft weight/recipient body weight ratio of 2.0%. After an uneventful early post-operative period, HAT was diagnosed by Doppler ultrasonography (USG) on the fifth post-operative day. Following angiographic evaluation, immediate exploration and reanastomosis was performed using an operation microscope. Post-operatively, the HA was patented by Doppler USG and graft function returned to normal. Now, 42 months later, the patient continues to do well with normal graft function, using a regimen of tacrolimus monotherapy for immunosuppression. In countries which have very limited resources for urgent re-transplantation, given their serious donor shortage, graft salvage may be the only option for patient survival when HAT occurs. In these circumstances, early diagnosis and immediate revascularization may be the only method for graft salvage. A daily routine of Doppler USG examination in the early post-operative period may provide a method for the early diagnosis of HAT, before liver enzymes are elevated and hepatic necrosis has begun.     

Rotavirus gastroenteritis among children under five years of age in Izmir, Turkey

Little is known about the epidemiology of rotavirus infection in Turkey. The aim of the study was to determine the incidence and clinical significance of rotavirus gastroenteritis, in view of the potentially available prevention by rotavirus vaccination. The study also sought to determine possible risk factors for rotavirus gastroenteritis. Therefore, 920 children under five years of age with acute gastroenteritis admitted to three pediatric hospitals in Izmir were studied. Rotavirus was identified in 39.8% of the children. Most children with rotavirus gastroenteritis (80.7%) were younger than two years of age. Marked seasonality of rotavirus gastroenteritis was observed, with a peak incidence from January to March. A total of 91% of rotavirus strains that were typed were of serotypes G 1-4. There was no significant difference among rotavirus-positive and rotavirus-negative patients with regard to family income. Compared with children who were exclusively breast-fed, those who were not exclusively breast-fed were at a two-fold greater risk of rotavirus diarrhea. Rotavirus gastroenteritis was significantly more severe than non-rotavirus gastroenteritis; 69% of children with rotavirus infection had severe gastroenteritis (score > or = 11). In conclusion, rotavirus is the most common cause of severe gastroenteritis among children under five years of age in Izmir. A new potent rotavirus vaccine, when available, will provide effective protection against severe rotavirus infection. Promotion of breast-feeding would augment the impact of rotavirus vaccines in preventing severe childhood diarrhea.     

Detection of achondroplasia G380R mutation from PCR amplicons by using inosine modified carbon electrodes based on electrochemical DNA chip technology

The detection of Achondroplasia G380R mutation from real samples was performed by monitoring the oxidation signal of guanine. Inosine-substituted 12-mer capture probes related to the homozygous or heterozygous alleles of Achondroplasia G380R mutation were adsorbed onto carbon paste electrode (CPE) surface. No guanine signal was obtained from the capture probes, since the inosine bases were electroinactive. Then, these probes were hybridized with the denatured PCR samples on the CPE surface. The hybridization between the probe and target sequences was determined by using the oxidation signal of guanine in connection with differential pulse voltammetry (DPV). The oxidation signal of guanine was observed as a result of the specific hybridization between the probe and PCR sample. The changes in the peak height of the guanine signal provided the information whether the PCR sample contained heterozygous allele or homozygous allele. Numerous factors affecting the hybridization and nonspecific binding events were optimized to detect down to 41.24 fmol/ml target DNA. The electrochemical detection of Achondroplasia G380R mutation from PCR samples greatly shortened and simplified the diagnosis for the homozygous mutant type, which is lethal for the newborn.     

A case of Lenz microphthalmia syndrome.

Lenz microphthalmia syndrome was first described by Lenz et al in 1955. The cardinal features of the syndrome are microphthalmia or anophthalmos, narrow shoulders, other skeletal anomalies, and dental and urogenital malformations. Here we present a case of Lenz microphthalmia syndrome who shows the typical characteristics and, additionally, dysgenesis of the corpus callosum associated with dilatation of the lateral ventricles. The patient, a 13 year old male, was referred to our hospital by a dental hospital for genetic counselling. On physical examination, height, weight, and head circumference were below the 3rd centile and he had brachymicrocephaly, a preauricular tag, microphthalmia, missing teeth, narrow shoulders, long, proximally placed thumbs, hypospadias, cryptorchidism, and a normal IQ. Ophthalmological examination showed microcornea, sclerocornea, absence of the pupil, no vision in the left eye and decreased vision and a small pupil in the right eye in addition to his bilateral microphthalmia. Cranial MRI showed dilatation of the lateral ventricles and dysgenesis of the corpus callosum.     

Seckel syndrome with Morgagni hernia

Seckel syndrome is an autosomal recessive disease presenting with microcephalic dwarfism, mental retardation and facial and skeletal abnormalities. Morgagni hernia is quite rare, constituting 1-6% of all diaphragmatic hernias. It is asymptomatic, especially in childhood. Morgagni hernia has never been reported in patients with Seckel Syndrome. Here we report a 3-year-old boy diagnosed as having Seckel Syndrome with Morgagni hernia, which has to be considered during physical examination of patients.