Transmissible virus dementia: evaluation of a zoonotic hypothesis

Creutzfeldt-Jakob disease (CJD) and kuru are subacute transmissible dementing encephalopathies characterized by spongiform changes in the brain. Scrapie is a similar slow viral encephalopathy which affects sheep, goats and certain other animals. Anecdotal reports suggest that Creutzfeldt-Jakob disease could be a zoonosis. To evaluate the possibility that CJD is acquired from animals, a case-control study was conducted on 26 well-documented CJD cases and 40 controls. Data were collected on exposure to animals through occupations, hobbies, sports and pets. An excess exposure to certain animals was noted among the patients compared to controls in relation to occupation (deer, monkey, squirrel; odds ratio (OR) = 8.9; p less than 0.10) and hobbies (deer, OR = 9.0; rabbit, OR = 6.0; p less than 0.05). Similarly, exposure to animal organs was significantly greater in the CJD group (OR = 20.9; p less than 0.005). Statistically significant increased exposure to sheep or goats was not found among the patients. However, since spongiform encephalopathy has a wider host range than sheep and goats, the increased exposure to certain other animals suggests that a zoonotic source for CJD should be further explored.     

Threatened abortion: sonographic distinction of normal and abnormal gestation sacs

In an attempt to determine whether sonographic evaluation alone can distinguish normal from abnormal gestation sacs, a retrospective analysis was performed of ultrasound (US) scans from 168 women with threatened abortion. Gestation sacs were judged to be abnormal on the basis of specific sonographic criteria including large size (greater than or equal to 25 mm mean sac diameter) without an embryo; distorted shape; thin (less than or equal to 2 mm), weakly echogenic, or irregular choriodecidual reaction; absence of a double decidual sac; and low position. Two criteria - large sac and distorted shape - had 100% specificity and were called major criteria. The remaining criteria were individually less specific, although 100% specificity was achieved when three or more of these minor criteria were demonstrated. When one major or three minor criteria were present, 53% of abnormal gestations were correctly identified without any false-positive diagnoses. The authors conclude that experienced sonographers can reliably identify many abnormal gestation sacs on a single examination.     

Esophageal cancer staging by CT: long-term follow-up study

To evaluate the utility of computed tomographic (CT) staging in patients with esophageal cancer, the length of patient survival was compared with pretherapy CT findings in 89 patients. Regardless of therapy, patients with evidence of mediastinal invasion, liver metastases, or abdominal adenopathy had a statistically shortened survival (P less than .05). Specific CT criteria that predicted a shortened survival included evidence of tracheal, aortic, or pericardial invasion. Patients with evidence of both mediastinal invasion and abdominal metastases had a mean survival of 180.4 days; those with no evidence, 479.6 days. The presence of enlarged upper abdominal lymph nodes indicated the worst prognosis (mean survival, 90 days). The patients with squamous cell tumors were classified by the CT staging system, and survival data were compared according to surgical procedure. Patients who underwent attempted curative surgery did not have a statistically significant difference in survival by analysis of survival curves but demonstrated a longer mean survival than those who underwent palliative or no surgery.     

The immunopathology of acute experimental allergic encephalomyelitis. V. A light microscopic and ultrastructural immunohistochemical analysis of fibronectin and fibrinogen.

Cellular expression and extracellular deposition of fibronectin and fibrin/fibrinogen in experimental allergic encephalomyelitis (EAE) in guinea pigs (GP) were studied by light and electron microscopic immunohistochemistry of the central nervous system (CNS). Normal GPs had few fibronectin+ and fibrin/fibrinogen+ CNS vessels. Positively stained vessels were more numberous in sensitized GPs prior to and after onset of EAE, and there were extracellular deposits of these molecules in inflammatory foci. Staining was greater in EAE-susceptible strain 13 GPs than in sensitized EAE-resistant strain 2 GP. On ultrastructural analysis both molecules were localized on endothelial cell luminal surfaces and on intravascular mononuclear cells. Fibronectin and the macrophage fibronectin receptor (A6F10) were found on mononuclear cells in parenchyma. Endothelial cell luminal surface fibronectin and fibrin/fibrinogen may mark and/or contribute to early immune events in EAE, including mononuclear cell margination and emigration in inflammatory sites. Genetic factors, cytokines, and components of coagulation may regulate these interactions in vivo.     

Renal allografts in acute rejection: evaluation using duplex sonography

Sixty-nine duplex sonographic studies were performed in 24 patients who had received renal allografts. After a prospective qualitative analysis of the Doppler waveforms, results were correlated with biopsy material and each patient's clinical course. Increased pulsatility of the Doppler waveform of intrarenal arterial flow constituted an abnormal study, indicating acute rejection. Overall sensitivity varied with the histologic form of rejection, with a 60% sensitivity for acute interstitial rejection with or without vascular rejection and an 82% sensitivity for acute vascular rejection. Overall specificity was 95% and 96%, respectively. Early rejection was also accurately detected in three patients less than 48 hours following kidney transplantation. Duplex sonography has a useful role in evaluating posttransplantation renal failure. Abnormal study results may obviate the need for biopsy and help in guiding clinical management.     

An autologous fibrinogen-based adhesive for use in otologic surgery

Successful middle ear surgery requires the availability of a safe, effective bonding material. Side effects caused by synthetic materials have led to the use of biologic adhesives; however, they carry the risk of transmission of infectious disease if they are prepared from pooled human blood. A procedure for the production of an autologous fibrinogen-based adhesive using polyethylene glycol to precipitate the fibrinogen-factor XIII component from plasma is described. This procedure requires 40 ml of whole blood and approximately 3 hours' preparation time, and it can be performed in any blood bank with the facilities for sterile techniques. This adhesive has been used successfully for otologic surgery in 12 patients, and further study of the use of this biologic adhesive for other microsurgical techniques should be undertaken.     

Lipomatous tumors and tumors with fatty component: MR imaging potential and comparison of MR and CT results

This retrospective study was performed to assess the potential of magnetic resonance (MR) imaging for demonstrating various types of lipomatous tumors and tumors with fatty component and to compare the results of MR with those of computed tomography (CT). MR examinations of 17 patients with 18 lipomatous tumors (16, benign; two, liposarcoma) and two patients with fibrosarcomas were reviewed; CT scans were available for comparison in all patients. In the 16 benign lesions (12 benign lipomas, two ovarian dermoid cysts, and two renal angiomyolipomas), the fatty component of the tumors was readily demonstrated by both MR and CT. The T1 and T2 relaxation times and spin density of benign lipomatous tumors were in a range similar to those of normal subcutaneous fat. Differentiation between lipomas and liposarcomas was achieved with both MR and CT. On MR images using a short repetition time (TR = .5 sec), liposarcomas (long T1) were imaged with a lower MR intensity than lipomas (short T1).