Glycosylation of high-affinity thrombin receptors appears necessary for thrombin binding.

Monosaccharide binding competition, lectin affinity chromatography, and glycosylation inhibitors have been used to determine if glycosylation plays a role in thrombin-receptor interactions. Mannose appeared to specifically inhibit thrombin binding to mouse embryo (ME) and hamster fibroblasts. Concanavalin A bound to antibody-purified receptor fractions, and was used as an affinity ligand to purify receptor fractions that retained thrombin binding activity. Cells treated with tunicamycin (6.25 ng/ml) for 24 h lost approximately 35% of their high-affinity thrombin binding sites, yet binding of receptor monoclonal antibody TR-9 was not affected, indicating that the receptor was present in the membrane, but unable to bind thrombin. Thus thrombin receptor glycosylation may be directly involved in thrombin binding.     

Eye movements in Daphnia pulex (De Geer).

1. The various types of eye movement exhibited by the cyclopean eye of Daphnia pulex were studied using high speed motion photography. 2. This rudimentary eye, which consists of only 22 ommatidia, can move through approximately 150 degrees in the sagittal plane and 60 degrees in the horizontal plane. 3. Four classes of eye movement were found: (1) a high speed tremor at 16 Hz with an amplitude of 3-4 degrees, which resembles physiological nystagmus, (2) a slow rhythmic scanning movement at 4 Hz, and 5-6 degrees amplitude, (3) large fast eye movements similar to saccadic eye movements and (4) optokinetic nystagmus produced by moving striped patterns. 4. Where the fast tremor occurred concurrently with the slow rhythmic scan, a Fourier analysis revealed that the former was the fourth harmonic of the latter.     

Management of patients with congenital hypothyroidism.

The biochemical state and treatment of 73 children and 44 adults up to the age of 40 with proved congenital hypothyroidism were assessed in a regional study in the north of England. The findings showed that a substantial proportion of the patients were having inappropriate treatment or were not taking their treatment regularly and that in some of these there were clinical effects.     

Relation between osmolality of diet and gastrointestinal side effects in enteral nutrition.

One hundred and eighteen patients with normal gastrointestinal function were randomly allocated to one of three feeding regimens in a double blind study to determine the relation between the tonicity of the diet and gastrointestinal side effects related to the diet and to evaluate the efficacy of "starter" regimens in reducing gastrointestinal side effects during enteral nutrition. Patients received a hypertonic diet with an osmolality of 430 mmol (mosmol)/kg (group 1), the same diet but with the osmolality increasing from 145 to 430 mmol/kg over the first four days (group 2), or an isotonic diet (300 mmol/kg) (group 3). All diets were prepared aseptically and administered by 24 hour nasogastric infusion. The mean daily nitrogen intake in group 1 was significantly greater (p less than 0.05) than that in both groups 2 and 3, and the mean overall daily nitrogen balance was significantly better (p less than 0.05) in group 1 than groups 2 and 3. The incidence of side effects related to the diet was similar in all three groups, but diarrhoea was significantly (p less than 0.001) associated with concurrent treatment with antibiotics. These findings show that undiluted hypertonic diet results in significantly better nitrogen intake and balance, that starter regimens reduce nutrient intake but not symptoms, and that diarrhoea is significantly related to treatment with antibiotics and not to administration of an undiluted hypertonic polymeric diet.     

Fulminating necrotizing amebic colitis with perforation: case report and review.

A seriously ill patient with diffuse abdominal tenderness of unknown cause is described. The diagnosis proved to be fulminating necrotizing amebic colitis with perforation. This case report serves as a reminder that amebiasis may occur in patients who have not been outside Canada, that it may readily be confused with other types of inflammatory bowel disease, and that particular care should be taken in obtaining a history of exposure. Before inflammatory bowel disease is diagnosed not only should the usual diagnostic tests such as stool examination and mucosal biopsy be done, but also serologic testing for amebiasis should be carried out.     

A comparative cytopathologic study of noninvasive and invasive squamous cell carcinoma of the lung

Atypical cells and tissue fragments from the sputum of patients with early and advanced stages of squamous cell carcinoma of the bronchus are objectively characterized and quantitatively compared in this paper. Four classes of single-cell features of cytoplasm, nucleus, nucleolus and nuclear-cytoplasmic ratio are analyzed as a function of cell size and tumor development stage. Distinct differences in the cellular patterns are observed which may enhance cytologic discrimination between noninvasive and invasive stages of squamous cell carcinoma of the bronchus. Initial results justify the application of more sensitive measurement techniques (i.e., automated cytology) to an enlarged data base.