Serum and Urine Fibrinogen-Fibrin-related Antigen (F.R.-Antigen) Levels in Renal Disease

The concentration of serum fibrinogen-fibrin-related antigen (F.R.-antigen) was measured in a group of 142 patients with various renal disorders, in 38 of whom urine F.R.-antigen was also estimated. Raised serum F.R.-antigen levels were present in 48% of the patients, with no particular preponderance in any diagnostic category apart from acute reversible intrinsic renal failure in which high levels were invariably present. Significantly-raised serum levels were also present in the patients with microangiopathic haemolytic anaemia and in those with the more severe degrees of renal impairment. Urine F.R.-antigen was increased in 34 of the 38 patients. The amount of F.R.-antigen in the urine correlated with the degree of proteinuria but not with the serum F.R.-antigen levels. The evidence relating to intravascular coagulation in renal disease is reviewed, and it is suggested that there is a high incidence of localized fibrinogen or fibrin degradation in the kidney, which is related more to factors such as the presence of uraemia and microangiopathic haemolytic anaemia rather than to the diagnostic category.     

High Dosage Metolazone in Chronic Renal Failure

Metolazone is a modified quinazolinesulphonamide and in a dose of between 4 and 7·5 mg is an effective diuretic in man with normal renal function. Fourteen patients with non-oedematous stable chronic renal failure (creatinine clearance ranging from 1·2 to 12 ml/min) were given metolazone in doses ranging from 20-150 mg. A noticeable increase in urine flow and sodium excretion occurred, free water clearance increased, and there was a small but significant increase in potassium excretion. No side effects were noted.     

Active, water-insoluble derivatives of D-glucose oxidase and alginic acid, chitin, and Celite

Treatment of 2-benzimidazolemethanol (4) with methanesulfonyl chloride and pyridine in chloroform afforded 2-(chloromethyl)-1-(methylsulfonyl)benzimidazole (6), which was also prepared by methanesulfonylation of 2-(chloromethyl)benzimidazole. Methanesulfonylation of α-(2-benzimidazolyl)benzyl alcohol (8) in chloroform yielded 2-(α-chlorobenzyl)-1-(methylsulfonyl)benzimidazole. 1-(Methylsulfonyl)-2-benzimidazolemethanol was obtained on methanesulfonylation of 4 pyridine at 0°, and α-[1-(methylsulfonyl)-2-benzimidazolyl]benzyl alcohol (12) was prepared from 8 by using the same reaction conditions. The reaction of 1-acetyl-2-(chloromethyl)-benzimidazole with silver methanesulfonate in benzene gave 1-acetyl-O-(methylsulfonyl)-2-benzimidazolemethanol. Compound 6 has some antitumor activity in the KB cell-culture system, and some antibacterial activity in the Staphylococcus aureus test-system; it is also active in preventing anaphylactic shock in a mouse test-system.     

Impulse Origin and Propagation in a Bipolar Sensory Neuron

Intracellular recording techniques were used to study electrical activity in bipolar sensory cells associated with crayfish tactile receptors. Several lines of evidence indicate that spikes evoked by natural stimulation of the receptor originate at a dendritic locus. Although overshooting spikes are recorded in the soma in response to both natural and antidromic stimulation receptor potentials are observed only rarely, and, when present, their amplitude is less than 5 mv. Impulses propagating centrifugally into the soma following antidromic stimulation always exhibit an inflection in the rising phase of the spike; however, orthodromic spikes are usually uninflected. Occasionally, orthodromic responses (in the soma) exhibit rather unusual wave forms. Such spikes evoked by natural stimuli are indistinguishable from those elicited electrically in the dendrite, but they do not resemble antidromic impulses. Because the axonal and dendritic boundaries of the soma have a low safety factor for spike transmission, at high frequencies invasion of the soma by dendritic spikes is impeded and often blocked. The soma region can thus act as a low-pass filter. The significance of this self-limiting mechanism for the behavior of the animal is not known; it is suggested, however, that this impediment is a potentially critical one, and may, in other situations, have encouraged the evolution of alternative arrangements.