The canal of the posterior ampullar nerve: an important anatomic landmark in the posterior fossa transmeatal approach

The canal of the posterior ampullar nerve is located between the inferior part of the internal acoustic meatus and ampulla of the posterior semicircular canal. It permits a more accurate localisation of the underlying labyrinth in inner-ear surgery. An anatomical and radiological study was undertaken to determine the importance the relationship between the canal and the labyrinth. Ten dry and 10 cadaveric temporal bone dissections, together with 20 high resolution CT scans of the same temporal bones were studied in an attempt to describe the anatomy of the canal of the posterior ampullar nerve. The length of the canal of the posterior ampullar nerve, the length of internal acoustic meatus, and distances from porus acusticus to the singular foramen and the transverse crest, and from the singular foramen to the vestibule and transverse crest, and from operculum to the sigmoid sinus and to the porus acusticus were measured. During the transmeatal posterior cranial fossa approach using the canal of the posterior ampullar nerve as a landmark enables more bone to be safely removed from the internal acoustic meatus thus preserving hearing.

(51)CrEDTA colonic permeability and therapy response in patients with ulcerative colitis

Orally administered (51)Cr-labelled ethylenediaminetetraacetic acid ((51)CrEDTA) has been used to evaluate intestinal permeability in inflammatory bowel disease, especially Crohn's disease. However, information about colonic permeability in ulcerative colitis (UC) is relatively scarce. The aim of this study was to investigate the urinary excretion of orally administered (51)CrEDTA, its relation to disease activity and its response to medical therapy in patients with UC. Forty-three patients with UC and 19 controls were examined. Disease activity was evaluated by endoscopy. In 19 patients with active UC, the (51)CrEDTA permeability test was repeated after medical therapy. (51)CrEDTA (95 microCi; 26 MBq) was given orally after an overnight fast and urine was collected over a 24 h period. The first urine samples were taken 5 h and the second 24 h after the oral administration of (51)CrEDTA. Urine samples were counted in a gamma counter. In controls, the median 5 h and 24 h excretions were 0.10% and 0.93%, respectively. Patients with UC showed significantly increased urine (51)CrEDTA excretion at both time intervals (5 h: 2.41%, P<0.0002; 24 h: 6.72%, P<0.0001). There was also a significant correlation between intestinal permeability and disease activity (5 h: r=0.45, P=0.0025; 24 h: r=0.51 P=0.0006). After medical therapy, (51)CrEDTA urinary excretion was significantly decreased (pre-treatment UC: 7.87%; post-treatment UC: 2.50%; P<0.0002). Briefly, the (51)CrEDTA test reflected colonic permeability in UC and might be useful as an indicator of disease severity. Moreover, this study suggested that, in patients with UC, medical therapy not only leads to the recovery of acute inflammation but also restores mucosal barrier integrity and function.

Successful heterotopic segmental liver transplantation from a live donor to a patient with Alagille syndrome

Alagille syndrome is characterized by a paucity of bile ducts in the liver. The syndrome is associated with some or all the features of chronic cholestasis, cardiac disease, skeletal abnormalities, ocular defects and a distinctive facial appearance. The most common finding is chronic cholestasis, which causes intractable pruritus, xanthoma, deficiency of certain metabolic nutrients and growth retardation. Cardiac abnormalities are the most common cause of death in these patients. It is unusual to see the clinical picture of hepatic failure resulting in cirrhosis and requiring transplantation, but liver transplantation is indicated in Alagille syndrome patients who have chronic cholestasis. If the disease is diagnosed in childhood, transplantation can improve significantly the patient's prognosis and the quality of life. In recent years, auxiliary liver transplantation has gained popularity for treating both acute and chronic liver disease. Heterotopic segmental liver transplantation is an alternative treatment modality for patients who do not require native liver removal. Individuals with Alagille syndrome are good candidates for this type of treatment. J Pediatr Surg 36:667-671.

Schwachman-Diamond syndrome. A case report

Schwachman-Diamond syndrome is an autosomal recessive disorder consisting of exocrine pancreatic insufficiency and neutropenia. The typical pathological finding with this syndrome is fatty infiltration in the pancreas of patients. We report a case of Scwachman-Diamond syndrome examined with abdominal ultrasonography, CT and radiography.

Schwachman-Diamond syndrome. A case report

Schwachman-Diamond syndrome is an autosomal recessive disorder consisting of exocrine pancreatic insufficiency and neutropenia. The typical pathological finding with this syndrome is fatty infiltration in the pancreas of patients. We report a case of Scwachman-Diamond syndrome examined with abdominal ultrasonography, CT and radiography.

Structure and function of adenosine receptors and their genes

Four adenosine receptors have been cloned from many mammalian and some non-mammalian species. In each case the translated part of the receptor is encoded by two separate exons. Two separate promoters regulate the A1 receptor expression, and a similar situation may pertain also for the other receptors. The receptors are expressed in a cell and tissue specific manner, even though A1 and A2B receptors are found in many different cell types. Emerging data indicate that the receptor protein is targeted to specific parts of the cell. A1 and A3 receptors activate the Gi family of G proteins, whereas A2A and A2B receptors activate the Gs family. However, other G proteins can also be activated even though the physiological significance of this is unknown. Following the activation of G proteins several cellular effector pathways can be affected. Signaling via adenosine receptors is also known to interact in functionally important ways with signaling initiated via other receptors.

Pediatric renal transplantation in Turkey: a review of 56 cases from a single center

In order to assess certain aspects of pediatric kidney transplantation (Tx) in Turkey, we retrospectively analyzed the results of 56 of these pediatric procedures performed at our center. From January 1986 to January 1998, 56 pediatric renal Tx (29 males, 27 females; 0-17 yr of age) were carried out at Başkent University Hospital. All were first-time Tx. Fifty-one (91%) patients were on hemodialysis and four (7.3%) were on peritoneal dialysis prior to Tx. Pre-emptive Tx was performed for only one patient. Living-related donors (LRD) provided 47 (84%) of the transplanted organs and cadaver sources were utilized for nine (16%) patients. The mean cold ischemia time (CIT) for cadaveric donors (CD) was 38.6 h (range 23-56 h). Among living-related graft (LRG) recipients, the average waiting time for Tx was 4 months for Tx performed after 1990 and 8 months for those prior to 1990 (p < 0.05). Median length of hospital stay for Tx was 17 +/- 1.1 and 18 +/- 1.4 days for LRG and cadaveric graft (CG) recipients, respectively. Fifteen of 47 (33%) LRG recipients and six of nine (67%) CG recipients received anti-rejection treatment within 30 days following the Tx surgery. Graft failure developed in 16 (12 LRG, four CG) recipients. Two patients developed Kaposi's sarcoma, 17 and 3 months after Tx. There were total of six deaths (four with functioning grafts). The 1-, 3-, and 5-yr graft survival rates were 93%, 75%, and 63%, respectively, and corresponding patient survival rates were 96%, 92%, and 77%. The social and educational status of 27 patients with functioning grafts were also evaluated. Our results showed that 56% of patients ended their education before high school and only three patients have been married. The high rate of school drop-out and unemployment among pediatric renal transplant recipients in our population underline the need for a more intensive rehabilitation program.

Stimulatory and inhibitory effects of adenosine A(2A) receptors on nerve growth factor-induced phosphorylation of extracellular regulated kinases 1/2 in PC12 cells

Effects of nerve growth factor (NGF), adenosine and an adenosine A(2A) receptor agonist (CGS 21680) on the phosphorylation of extracellular-regulated kinases 1/2 (ERK1/2) were examined in PC12 cells. Adenosine and CGS 21680stimulated ERK1/2, but inhibited the phosphorylation of ERK1/2 induced by a 10 min incubation with NGF. Longer treatment with CGS 21680 and NGF (1-2h) resulted in an additive effect on the activation of ERK1/2. Forskolin exerted the same effects, suggesting that they are mediated by cyclic AMP. These results indicate that adenosine A(2A) receptor induced increases in cyclic AMP can stimulate ERK1/2 phosphorylation per se, inhibit the initial and enhance the late NGF-induced activation of ERK1/2. These results may be explained by the fact that NGF action is mediated via different pathways at early and late time points.

Intraosseous lipoma of the frontal bone. A case report

Intraosseous lipomas are among the most uncommon bone tumors. They arise most often in the appendicular skeleton. There are very few reported cases of intraosseous lipomas within the skull bones. We report a case of intraosseous lipoma of the frontal bone with conventional radiography and CT findings.

Giant cell tumor of the fourth metacarpal bone

Giant cell tumor is among the rare tumors of the bone. We present a case of metacarpal giant cell tumor with radiographic, computed tomographic (CT) and histologic findings, as well as grey scale and Doppler sonographic features. We also present the "doughnut"-shaped appearance on scintigraphy of the lesion, which has not been shown on a metacarpal giant cell tumor.

Absence of the azygos vein

A rare case of the absence of the azygos vein (AV) is presented. Imaging findings on plain chest film and on contrast-enhanced spiral computed tomography (CT) are described, and embryology of azygos and hemiazygos veins (HV) is reviewed. On PA chest radiographs, both the absence of AV shadow on its usual location and the presence of the aortic nipple may consider agenesis of AV, and this anomaly can be easily confirmed by CT.