In vivo B/A determination in a mammalian organ.

Investigations of the ultrasonic nonlinearity parameter B/A have been restricted previously to in vitro preparations. The parameter B/A has now been determined in vivo in cat liver and found to have the same value as in vitro determinations. The finite amplitude method was used, with a substitutional procedure to improve accuracy.

Treatment with artificial beta-cell decreases very-low-density lipoprotein triglyceride synthesis in type I diabetes.

The effect of restoration of euglycemia with the artificial beta-cell (Biostator GCIIS) on triglyceride metabolism was studied in seven normolipidemic patients with type I diabetes mellitus. Very-low-density lipoprotein triglyceride (VLDL-TG) transport was determined with [3H]glycerol as an endogenous precursor of VLDL-TG; the resultant kinetic data were evaluated by multicompartmental analysis. Studies of triglyceride metabolism were performed in diabetic patients taking their usual dose of subcutaneous insulin (control study) and after 72 h of euglycemia with the artificial beta-cell (Biostator study).

Thrombolytic therapy in acute myocardial infarction in the elderly.

Fifty-seven elderly patients (35 males, 22 females; age range 65-80 years, mean 70 years) with acute myocardial infarction received thrombolytic therapy within 8 h using either streptokinase or anisoylated plasminogen streptokinase activator complex. Coronary artery reperfusion was confirmed by early coronary arteriography. The overall reperfusion rate was 77%.

Achievement of coronary artery patency by use of anisoylated plasminogen streptokinase activator complex in acute myocardial infarction.

Anisoylated plasminogen streptokinase activator complex (APSAC) is a recently developed thrombolytic agent with high fibrin-binding potential and sustained release pharmacokinetics (plasma half-life 70 minutes). Following studies of its intracoronary use, the efficacy was examined, in an open study using coronary angiography, of a single bolus dose of 30U given intravenously to 94 patients within 6 hours (mean 2.97 hours) from the onset of symptoms of myocardial infarction.

Attenuation and speed of ultrasound in lung: dependence upon frequency and inflation.

The dependence of the speed of sound and the attenuation coefficient upon exposure frequency, in the range of 1-5 MHz, and upon level of inflation, in the range of mass density 0.35-0.7 g/cm3, are reported.

Analogy between fibrinogen and casein. Effect of an undecapeptide isolated from kappa-casein on platelet function.

A large number of similarities have previously been noted between the blood and milk clotting phenomena [Jollès, P. (1975) Mol. Cell.

Diet-induced essential fatty acid deficiency in ambulatory patient with type I diabetes mellitus.

We report a case of symptomatic essential fatty acid deficiency (EFAD) occurring in a free-living individual with type I diabetes mellitus who was voluntarily following a high-carbohydrate, fat-restricted diet. The patient was 43 yr old with type I diabetes for 18 yr and no chronic complications. His self-imposed diet excluded all red meats, fats, and oils.

Arteriosclerotic heart disease in the elderly.

Arteriosclerotic heart disease is now the most important cause of morbidity and mortality in the elderly. Clinical presentation may be less typical than in younger patients, and therefore, a high index of suspicion is necessary. Although selectivity is required in regard to investigations, age should not deter the physician from establishing a diagnosis and quantifying the extent of the coronary artery disease.

Ultrasonically induced morphological changes in the mammalian neonatal spinal cord.

Light and electron microscopy were employed to examine ultrasonically irradiated murine neonate spinal cords. Spinal cord damage was always associated with functional changes, i.e.

Low-kilohertz-water-borne ultrasound biological effects.

The effects of 25 kHz ultrasound on murine testes was studied, as mimicking possible World WAR II SONAR exposure to swimming maintenance personnel. Very few specimens were found to exhibit morphological tissue alterations, depending upon length of exposure time and proximity of the source to the tissue. Thermal processes seem to be eliminated, but microstreaming may be implicated, as the physical mechanism(s) of interaction.

The potentiating effect of platelet on plasminogen activation by tissue plasminogen activator.

A new role for platelets in fibrinolysis is proposed. Platelets (euglobulin from platelet rich plasma and from human platelet extract) may potentiate plasminogen activation by tissue plasminogen activator (tPA). The potentiating activity was detected by both chromogenic substrate and fibrin plate analysis.

Aggregation of chymotrypsin-treated thrombasthenic platelets is mediated by fibrinogen binding to glycoproteins IIb and IIIa.

Previous experiments demonstrated that chymotrypsin, but not adenosine diphosphate (ADP), exposed fibrinogen binding sites on platelets from patients with Glanzmann's thrombasthenia. Three of these patients have been reexamined, and previous observations were confirmed. The quantity of iodine 125-labeled glycoprotein IIb (GPIIb) and glycoprotein IIIa (GPIIIa) on the platelets of these patients was considerably less than normal but was detectable by immunoprecipitation, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and autoradiography.

Sociomedical contributions to trachoma research and intervention.

Although the importance of human factors in the transmission and control of blinding trachoma has long been recognized, little sociomedical research has been undertaken on this disease. The trachoma literature contains considerable anecdotal information and a few reports relating to human behavioral, cultural, social, and economic factors, but systematic study in this area is needed. The potential range of sociomedical contributions to trachoma research is wide, including studies on the transmission of the disease, its consequences (especially blindness), and the planning, logistics, monitoring, and evaluation of intervention programs.

Cultivation of macrophages derived from human malignant effusions.

Macrophages, isolated from malignant effusions, were cultured in vitro in media containing GCT/CM as a source of granulocyte-macrophage (GM) colony-stimulating factor (CSF). Cells were periodically examined for macrophage-specific cell surface antigens and functional activity. The number of macrophages increased sixfold during 15 days in culture.

Haematocrit in patients attending a hypertension clinic.

In view of recent interest in the relationship of haematocrit and blood viscosity to hypertension and vascular disease, we have analysed retrospectively the relationship of haematocrit to blood pressure, vascular complications and other variables in 2,381 patients referred to the Glasgow Blood Pressure Clinic. Haematocrit correlated negatively with age and systolic pressure in men, and positively with age and systolic pressure in females. Positive correlations were found in both sexes between haematocrit and serum alanine aminotransferase (possibly due to mutual correlation with alcohol); and between haematocrit and overweight (Quetelet Index) but not obesity (Ponderal Index).

Ultrasonic absorption and permeability for liposomes near phase transition.

The specific ultrasonic absorption coefficient per wavelength as a function of temperature in the vicinity of the phase transition of liposomes, composed of a 4:1 mixture of dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylglycerol (DPPG), of different sizes was determined using an acoustic interferometer. Small unilamellar vesicles (SUV) and multilamellar vesicles (MLV) yielded results similar to those in the literature, viz., an absorption maximum at the transition temperature.

Impaired catabolism of very low-density lipoprotein-triglyceride in a family with primary hypertriglyceridemia.

In this report, kinetic studies of plasma very low-density lipoprotein-triglyceride (VLDL-TG) were examined in five brothers (three affected and two unaffected) from a family with primary hypertriglyceridemia. Synthesis and catabolism of VLDL-TG were studied by in vivo labelling of plasma TG with 3H-glycerol, and multicompartmental analysis of the plasma die-away curves. Results of the kinetic studies revealed the following information: (1) one brother, who had the highest plasma TG level and was obese, had both overproduction and a reduced fractional catabolic rate (FCR) of VLDL-TG; (2) second brother, who had moderate hypertriglyceridemia, had a low FCR and high-normal synthesis of VLDL-TG; (3) a third, who had only mildly elevated TG, had a low FCR and normal synthesis of VLDL-TG; and (4) the two normolipidemic brothers had neither overproduction nor decreased FCR of VLDL-TG.

Determination of the nonlinearity parameter B/A of biological media.

The nonlinearity parameter B/A has been determined for various biological solutions and soft tissues using the thermodynamic and finite amplitude methods. Agreement between the two methods is better than 10% for the tissues and 1% for the solutions. Fat has a B/A value around 11, the highest among soft tissues studied.

Percoll density gradient separation of cells from human malignant effusions.

A simple method is described for the separation of cells derived from effusions of patients with adenocarcinomas in discontinuous density gradients of Percoll. After separation, cells from different fractions were analyzed by morphologic, histochemical and immunologic criteria. Total cell recovery from 27 experiments was 67 +/- 4%.

Cellular inactivation by heat and shear.

Inactivation of Chinese hamster V79 cells in vitro by a temperature elevation to 43 degrees C and with Couette shear flow was investigated. The shear stresses were chosen to mimic those produced by ultrasound of approximately 3 MHz and 3 W/cm2 within the chambers employed by earlier investigators studying ultrasonic inactivation of cellular processes. The combined shear and thermal stresses produced survival curves exhibiting a summating effect among these two stresses and remarkably similar to the ultrasound/thermal survival curves.

A routine system for monitoring perinatal deaths in Scotland.

Since 1983 the monitoring of perinatal deaths in Scotland has been incorporated into the established data collection system which monitors maternal and child health in Scotland. This paper describes the transition from a research project to the routine system and the extension of the data collection to include paediatric and pathological findings. This information is provided by local co-ordinators in active clinical practice.

Secretion of transforming growth factors by primary human tumour cells.

We examined the ability of primary human tumour cells to secrete diffusible factors capable of stimulating anchorage independent growth of normal rat kidney fibroblast (NRK) cells. Conditioned media (CM) prepared from cells derived from 31/43 patients with adenocarcinoma of the breast, colon, ovary or lung were found to induce growth of NRK cells in soft agar. The ability of the CM to induce anchorage independent growth was enhanced in 25/35 cases by the presence of epidermal growth factor (EGF).

Diurnal variation of blood pressure in elderly patients with essential hypertension.

Twenty-one elderly patients with essential hypertension, all over 65 years of age, were subjected to automated noninvasive 24-hour blood pressure measurement. Readings were obtained every 7.5 minutes throughout the day.

Systemic and renal effects of enalapril and its effects on cardiac mass.

Enalapril is a new angiotensin converting enzyme (ACE) inhibitor and has been shown to be of benefit in the treatment of both renovascular and essential hypertension. We have studied the systemic and renal haemodynamic, biochemical and cardiac adaptive changes induced by this agent in eight patients with essential hypertension before and after 12 weeks of therapy. Mean arterial pressure fell from 110 to 90 mmHg (P less than 0.