CT and MR imaging findings in adults with cerebellar medulloblastoma: comparison with findings in children.

The goal of this study was to determine if certain imaging features suggest the diagnosis of cerebellar medulloblastoma in adults and to determine how often the classic CT appearance seen in children is present in adults. The study included 28 adult patients with proved cerebellar medulloblastoma. The tumor was located in the cerebellar vermis in 14 patients and in a cerebellar hemisphere in 14 patients. Thirteen patients had unenhanced CT of the brain, all patients had contrast-enhanced CT, and eight patients had unenhanced MR imaging. The imaging features in adults were compared with those in children, as described in the literature. In our adult patients, all tumors were hyperdense compared with gray matter on unenhanced CT and showed a slight to moderate increase in density after injection of contrast medium. Thirteen lesions had well-defined margins, and 15 had poorly defined margins. Low-density areas consistent with cystic and necrotic degeneration were detected in 23 (82%) of the 28 tumors. By comparison, in children, medulloblastoma usually originates in the vermis. As in adults, the mass is hyperdense on unenhanced CT, but enhances markedly and homogeneously after injection of contrast medium. Usually no evidence of cyst formation or necrosis is seen, and the tumor margins are well defined. This classic CT appearance of medulloblastoma in children was identified in only three (11%) of the 28 adult patients. Medulloblastoma has a variable MR appearance in both children and adults. On T2-weighted images, lesions are hypo-, iso-, or hyperintense compared with normal gray matter. The CT findings of medulloblastoma in adults usually differ from those of medulloblastoma in children. The tumor has a variable and nonspecific appearance in adults and should always be considered in the differential diagnosis of a mass in the posterior fossa.     

Porphyria cutanea tarda associated with autoimmune hypothyroidism, vitiligo and alopecia universalis.

The aetiology of porphyria cutanea tarda (PCT) has not been elucidated, but the possibility of an autoimmune mechanism has been proposed. We report a case of an unknown clinical combination of PCT with autoimmune hypothyroidism, alopecia universalis and vitiligo with thyroid and parietal cell circulating antibodies. This is highly suggestive of underlying autoimmune damage in this patient.     

The cardioprotective action of nifedipine during short-term transient ischemia

To determine the therapeutic activity on regional myocardial function of nifedipine intravenous administration (0.16 mg/kg) during short term myocardial induced ischemia, we used 6 mongrel dogs anesthetized and intubated those who we have implanted 3 pairs of ultrasonic crystals in the subendocardial layer. Utilizing an open chest canine model we performed total 1 minute and partial 2 minutes 30 seconds alternative obstructions, controlled with electromagnetic flowmeters in the anterior descending (AD) and circumflex (Cx) coronary arteries before and after drug administration. During the 70-80% obstructions we have shown a significant improvement in segment shortening, reduced by ischemia, in the ischemic and peri-ischemic zone. The ischemic markers, per cent increment of end diastolic length (% IEDL) and per cent increment of end systolic length (% IESL), have shown significant improvement during partial obstructions in the ischemic and peri-ischemic zone. After total obstructions the improvement on regional myocardial function is less marked and limited to ischemic zone.     

Diagnosis of hairy leukoplakia by exfoliative cytologic methods.

The cytologic characteristics of hairy leukoplakia (HL) are described based on the findings observed in four lesions. All cases were confirmed by histologic study, and Epstein-Barr virus DNA was detected by means of in situ hybridization of tissue sections. All smears from the lesions exhibited a distinctive appearance and three types of epithelial changes were observed: (1) intranuclear inclusions of Cowdry type A, (2) intranuclear inclusions with a ground-glass appearance, and (3) clumping and margination of chromatin around the nuclear membrane. Other findings were the presence of bacterial colonies in all lesions and Candida organisms in three of them. The results of this study suggest that conventional exfoliative cytologic examination may prove to be a useful, simple, cost-effective, and reliable method to diagnose hairy leukoplakia.     

The health impact of stray and wild cats in the human environment]

The population of stray cats in towns expands due to irresponsible behaviour of humans who allow them to enter cellars, hot water canals, store rooms etc. As a result of frequent feeding some specimens become tame, lose their shyness and on contact with humans and domestic animals they can become the source of some infectious agents. The most important of thus transmitted diseases is rabies. Cats become infected from foxes on rubbish heaps on the periphery of communities. More than 60% of cases of rabies of domestic animals are found in cats. Toxoplasmosis--cats excrete the infectious stage of the causal agent in their excreta. In the same manner also the agent causing intestinal salmonelloses is excreted. More than 5% cats are infected. Via excreta also the causal agents of toxocariasis are spread--the larvae of cat thread worms settle in the internal organs of humans (larva migrans). The assumed incidence in cats is as high as 50%, as suggested also by the high positivity of specimens from children playgrounds. Stray cats may be the source of agents causing various dermatomycoses and of ectoparasites.     

Tracheostomy in spinal cord injured: frequency and follow up.

Among 600 traumatic spinal cord injured (SCI) patients admitted during a 20 year period, 67 had a tracheostomy performed (11.2%). Of these 67 patients 46 had a cervical SCI. A concomitant thoracic trauma had occurred significantly more often in the group with thoracic or lumbar SCI than in those with a cervical SCI. The period from injury to tracheostomy was 0-48 days (median 4.4 days), and from tracheostomy to decannulation 3-167 days (median 31 days). At follow up 20 (30%) had died, primarily because of respiratory problems. Of the remaining 47 patients, 43 (91%) responded to a follow up questionnaire 3.5-21.7 years (median 10.4 years) after the injury. In the follow up 53% reported never to have had any inconvenience or trouble related to the tracheostomy. The major inconvenience among the others had been of cosmetic origin (28%), and 3 had had a surgical revision for this reason. At the time of follow up 9 patients (21%) still had certain complaints, primarily described as difficulty in swallowing. Minitracheostomy might in the future reduce the number of these complications.     

Influence of bile on the severity of acute experimental pancreatitis induced by closed duodenal loop in rat.

The study was performed to assess the ethiological role of bile in acute pancreatitis provoked by closed duodenal loop in rat. In group I a closed duodenal loop was created by method of Nevalainen. A similar operation was performed in group II, but the common pancreatico-biliary duct was ligated just under the liver. In the control group (group C) only the mobilization of duodenum was performed. After 24 hours the mortality rate was 20% in group I, but 0% in group II and C. The amount of ascitic fluid showed significant elevation in group I versus II and group C, and in group II as compared to group C, too. The serum amylase was significantly higher in group I than group II and group C, and in group II was also higher as compared to group C. Serum total protein differed significantly between all groups, while albumin and total calcium were significantly lower in group I than group II, but group II was only slightly reduced versus group C. Histology showed no differences between groups I and II, but both differed significantly from group C. In conclusion bile seems to be an aggressive factor in pathogenesis of acute pancreatitis induced by closed duodenal loop in rat, but other factors may play more important roles.     

Three-dimensional computerized tomography in trauma surgery. A case presentation]

Three-dimensional images of bone structures can easily be reconstructed from computed tomography data. The technique and the advantages of contemplating reconstructions of bone defects in different directions are described. A special software programme allows to combine all data which are given by the standard CT. The slice diameter is two millimetres. The reconstruction shows bone surfaces in all required views. In traumatic and orthopaedic surgery 3-D-CT is useful in the analysis, detection and preoperative planning of comminuted bone injuries of the spine, pelvis, knee, shoulder and the calcaneus. With this technique it is possible to see the bone in its topographic constellation, to observe fractures in unusual directions and to identify fragments from each other. The surgeon gets a lot of additional information which is helpful to decide on the incision, the reduction and the fixation of fragments. Undesirable effects during operation are reduced, which leads to a more accurate treatment and subsequent better results.     

Molecular characterization of a virulence-associated epitope on the lipopolysaccharide of Legionella pneumophila serogroup 1.

For identification of lipopolysaccharide (LPS)-associated epitopes of Legionella pneumophila serogroup 1, LPS of strain Philadelphia 1 was investigated using monoclonal antibodies (MAbs). The O-specific chain of LPS is a homopolymer of 5-acetamidino-7-acetamido-8-O-acetyl-3,5,7,9-tetradeoxy-D-glycero- L-galacto- nonulosonic acid. At least four immunoaccessible epitopes were recognized by different MAbs on the intact LPS. After O-deacetylation of LPS, the reactivity of one of the MAbs (MAb 3/1) was lost, indicating thus that the corresponding epitope is associated with the 8-O-acetyl group. Since the reactivity pattern of the MAb 3/1 is identical with those of the MAb 2 which was considered as a virulence marker for serogroup 1, this epitope may be involved in mediating virulence in L. pneumophila. Four MAbs specific to strains of serogroup 1 other than the monoclonal subtype Philadelphia recognized epitopes on the O-deacetylated LPS of strain Philadelphia 1 and, therefore, the virulence-associated epitope blocks recognition of the immunodeterminants that are accessible on the intact LPS of the strains lacking this epitope.