Functional domains of human interferon gamma probed with antipeptide antibodies

Functional domains of biologically active polypeptide molecules can be sought by raising antibodies to synthetic peptides. Human interferon gamma (HuIFN gamma) was thus studied, using two peptides based on candidate regions representing amino acids 7-16 and 121-130 of the HuIFN gamma molecule. These were conjugated to bovine serum albumin prior to immunization of rabbits. High titres of antipeptide antibodies which recognized the synthetic peptides were elicited in all of the four rabbits injected. The antipeptide antibodies from one of the rabbits immunized with the C-terminal (121-130) peptide detected native HuIFN gamma at a concn as low as 300 IU/ml, but the antipeptide antibodies from the rabbit immunized with the N-terminal (7-16) peptide did not detect HuIFN gamma. The IFN gamma-reactive antipeptide antibodies (anti-121-130) did not neutralize the antiviral activity of HuIFN gamma in a cytoprotection assay. These data and other studies establish that the C-terminus of HuIFN gamma is not essential for full antiviral activity and indicate an application of antipeptide antibodies in the analysis of structure-function relationships of cytokine molecules.     

Comparison of eight kits for the diagnosis of pregnancy.

The results obtained with eight pregnancy kits on 735 urines were compared. Overall accuracies were similar and fairly high (93.4 to 95.37%), although only 78.28% of all pregnancies were simultaneously detected by all eight kits. It is suggested that the different performances of each kit could be accounted for not only by lack of product homologation, differences in kit sensitivity, and laboratorian error, but also by the presence of various hormonal components in various concentrations in the urines of pregnant women, and by the presence of different antibodies against these hormonal components in various concentrations in the antisera included in the various kits.     

IFN-alpha and IFN-beta: a link between immune memory and chronic inflammation

The majority of expanded T cells generated during an immune response are cleared by apoptosis. Prevention of death in some activated T cells enables the persistence of a memory T-cell pool. Here, observations that IFN-alpha and IFN-beta inhibit activated T-cell apoptosis are described. Although this enables memory T cells to persist without antigen, excessive IFN-alpha or IFN-gamma secretion might lead to chronic inflammation.     

Eccentric nephroscopy for the incarcerated nephrostomy

Following a percutaneous stone extraction and demonstration of antegrade flow, conventional methods of traction and coaxial dilatation failed to allow removal of a Stamey-Malecot nephrostomy. An eccentric track was created for nephroscopy. Grasping forceps were used to cut the fibrous tissue from the "wings" of the nephrostomy tube to allow its easy withdrawal. The combined approach by the radiologist and urologist safely overcame the fibrous entrapment.     

Semi-quantitative assessment of tibial blood flow and distribution in response to surgical intervention using first pass radionuclide angiography and intravascular vital dye

The acute vascular response in bone to surgical trauma was investigated utilizing a sheep model. Blood flow and distribution were determined using two methods; perfusion of the vasculature with an intravascular vital dye (Disulphine blue) prior to euthanasia and by radionuclide angiography (RNA) before and after each surgical intervention. The pattern of Disulphine blue distribution provided a good indication of local perfuslon and response to surgical trauma (drilling holes). Radionuclide angiography provided a dynamic image of the vascular response to surgical trauma. The generation of time activity curves of the first pass of radionuclide bolus enabled calculation of the relative blood flow through selected regions.

For both techniques areas of ischaemia were apparent which were directly related to the location of screw holes. We conclude that factors other than bone plate contact influence the ischaemia that develops in bone subsequent to the application of bone plates.     

Diabetic foods and the diabetic diet: A British Diabetic Association Discussion Paper

The role of special ‘Diabetic’ foods in the diabetic diet is considered and the following conclusions are drawn.

• 1 Most diabetic foods provide slightly, but not substantially, less energy than comparable non-diabetic products.
• 2 Many diabetic foods have a higher fat content than their non-diabetic equivalents. This is contrary to the requirements of the 1984 Food Labelling Regulations.
• 3 Many diabetic products have a relatively high content of protein.
• 4 In percentage terms, the greatest difference between diabetic and non-diabetic foods remains that of carbohydrate content, particularly carbohydrate other than fructose or sorbitol. On a per portion basis (for instance per teaspoon of jam) the difference is relatively small and likely to be of minimal practical significance.
• 5 Diabetic foods cost between 1.5 and 4 times as much as their non-diabetic equivalents.
• 6 Some ordinary reduced-sugar/low-calorie products are preferable to diabetic products in terms of fat and energy content and cost.
• 7 The promotion and widespread availability of diabetic foods tend to delude patients into believing that these products are advantageous, or even necessary. Their existence also undermines current dietary teaching by implying that diabetics cannot eat normal foods.
• 8 Diabetic foods offer no significant physiological or psychological benefits to diabetic patients and can even be counterproductive to good diabetic control. There is no longer a need for special diabetic foods in the modern dietary management of diabetes.