Clinical and radiographic features of simple and hydatid cysts of the liver

The advances of hydatid chemotherapy and the non-operative management of simple (epithelial) hepatic cysts make a correct diagnosis of increasing importance. Twenty-six patients with hepatic hydatid cysts and eleven with simple cysts were reviewed. In both groups clinical presentation was most frequently due to pain. Sex, age and size of the cysts were similar. Hydatid serology was negative in six of the hydatid patients (23 per cent). None of the simple cyst patients had positive serology but one had a borderline titre. Ultrasound and computerized tomography identified daughter cysts within the main cyst in only 17 hydatid cysts (65 per cent) and considerable intra-cyst debris was also present in five of the simple cysts. Seven of the simple cysts were deroofed surgically and the remainder underwent percutaneous aspiration. Sixteen of the hydatid cysts were found to have a biliary communication whereas this was not found with any simple cyst. The difficulties in making a precise diagnosis in some patients with a liver cyst should deter the interventional radiologist and restrain the hydatid chemotherapist.     

Comparison of smear and imprint techniques for rapid diagnosis in neuro-oncology

The smear and imprint techniques were applied to brain tumor biopsy specimens and the resultant preparations compared for preservation of architecture and cell morphology. The imprint gave excellent detail of cell morphology and good preservation of architecture, especially in soft tumors. The method has enabled a rapid diagnosis to be made in 100 cases of intracranial lesions and is a valuable complement to smear and cryostat sections.     

Effects of Increasing Gestation,Cortisol and Maternal Undernutrition on Hypothalamic Neuropeptide Y Expression in the Sheep Fetus

We have characterized the localization and the ontogenetic changes in Neuropeptide tyrosine (NPY) before birth and investigated the regulation of NPY expression by cortisol and undernutrition in the fetal sheep hypothalamus during late gestation. Using immunohistochemistry, we have identified NPY-containing neurons in the infundibular nucleus and the internal layer of the median eminence in fetal hypothalami collected between 110 and 147 days gestation. NPY projections were also present in the paraventricular nucleus (PVN) of fetal hypothalami at all ages between 110 days gestation and term. There was a significant increase in the amount of immunoreactive NPY/g hypothalamus between 87 and 113 days and 131–140 days gestation and a further significant increase after 141 days gestation. The total hypothalamic content of immunoreactive NPY increased significantly between 87 and 113 days and 141–145 days gestation. The levels of NPY mRNA: 18S rRNA in the mediobasal region of the fetal hypothalamus were significantly higher at 145–146 days gestation than at any earlier gestational age between 116 and 141 days gestation. Cortisol (2.5–3.0 mg/24 h) was infused intrafetally between 109 and 116 days gestation. The ratio of NPY mRNA: 18s rRNA in the mediobasal region of the fetal hypothalamus was significantly higher in the cortisol-infused group when compared with the saline-infused control group at 116 days gestation. Maternal, and hence fetal undernutrition, was induced between 110 and 146 days gestation. At 145–146 days gestation the ratio of NPY mRNA: 18S rRNA in the mediobasal region of the fetal hypothalamus was significantly higher in the undernutrition group when compared with control animals. We have therefore demonstrated that NPY is present in the hypothalamus of the sheep fetus before birth and that hypothalamic NPY content and NPY mRNA increase before delivery. We have also found that glucocorticoids and undernutrition stimulate increases in NPY mRNA levels in the hypothalamus before birth.     

Enhancement of macrophage microbicidal activity: supplemental arginine and citrulline augment nitric oxide production in murine peritoneal macrophages and promote intracellular killing of Trypanosoma cruzi.

The generation of nitric oxide (NO) is largely responsible for the intracellular killing of Trypanosoma cruzi by activated macrophages. The present study was carried out to determine whether the production of NO by activated murine macrophages cultured in physiologic levels of arginine can be augmented by increasing the availability of arginine, the substrate for NO biosynthesis. Increased exogenous arginine or citrulline resulted in a significant increase in NO production and complete clearance of the parasites by activated macrophages. As citrulline fully substituted for arginine in supporting NO production and trypanocidal activity, these results demonstrate the expression of a highly active citrulline-NO cycle in activated macrophages and that levels of arginine in plasma are limiting with respect to both NO production and trypanocidal activity in these cells. The results indicate that increasing plasma substrate levels for both arginine and NO biosynthesis may represent a means of enhancing microbicidal activity in vivo.     

Coexistence of Neoplasia and Cortical Dysplasia in Patients Presenting with Seizures

Summary: Tumors and cortical dysplasia are associated with epilepsy, but few studies have examined the coexistence of neoplasia and dysplasia in these patients. We studied 13 patients (age 4–29 years) with recurrent seizures of 1 month to 21-year' duration (median 72 months). Ten patients were aged <21 years. Imaging studies localized the lesion to the temporal lobe (10 patients), parietal lobe (2 patients), and frontal lobe (1 patient). Tumors included ganglioglioma (8 patients), dysembryoplastic neuroepithelial tumor (DNT) (3 patients), and low-grade as- trocytoma (2 patients). Cortical dysplasia, including atypical aggregates of neurons (6 patients), multifocal loss of the cortical laminar architecture (7 patients), and neurons in the molecular layer of the cortex (3 patients) were observed near but separate from the tumor. Coexistence of certain tumors with cortical dysplasia, most frequently observed in the pediatric population, suggests a hamar-tomatous/dysplastic nature of the neoplasms.     

Does teaching audit improve standards,and affect MCQ results in undergraduate trauma and orthopaedic tuition?

Over the study period from 1981 to 1987 inclusive, student critiques were scored to indicate the undergraduates' perception of the quality of teaching they received on each 2-month attachment to the trauma and orthopaedic surgical departments of two teaching hospitals. The medical staff and the environment in the two teaching hospitals were different. It was found that while the mean MCQ results did not change significantly throughout the study period, an improvement was noticed in the perceived quality of undergraduate tuition, especially at one hospital.     

Field evaluation of polycarbonate versus conventional safety glasses

Of all the causes of eye injury, gunshot has recently been cited as resulting in the highest rate of blindness and the lowest rate of visual recovery. Many of these cases are hunting accidents in which safety glasses could have prevented or lessened ocular damage. To evaluate the effectiveness of various types of safety glasses, we fired a Remington automatic shotgun at mannequin heads fitted with one of four types of safety lenses. From a distance of 10 yards, only polycarbonate lenses provided even partial protection. At 30 yards, polycarbonate and heat-treated lenses provided the best protection, whereas chemically treated and CR39 lenses provided significantly less protection. We recommend that hunters using shotguns in areas of poor visibility wear widely available polycarbonate safety glasses as well as "hunter's orange" to minimize their risk of devastating ocular gunshot injury.     

Planning and spatial working memory in Parkinson''s disease.

The higher level cognitive function of planning was studied in a group of medicated Parkinson's disease patients and a group of matched control subjects, using a computerised version of Shallice's Tower of London task. Baseline measurement of the ability to execute a given plan of action, to generate low level strategies required for efficient searching, and spatial working memory capacity, all of which contribute to performance on the planning task, established that the Parkinson's disease group was unimpaired on any of these measures. On the Tower of London task, the Parkinson's disease group was also unimpaired in terms of the average number of moves required to solve a problem. However, a specific planning deficit was evident when "thinking" times were analysed, and this was after the confounding influence of motor initiation and execution times had been carefully extracted from total performance times. This finding is discussed in relation to putative functions of the frontal lobes and basal ganglia, and an attention-switching hypothesis is developed to account for it.