NEW TAXONOMIC CRITERIA IN THE CLASSIFICATION OF CHLOROCOCCUM SPECIES. I. PIGMENTATION12

Eighteen isolates of Chlorococcum were incubated under defined culture conditions for 6-7 weeks. At that time, isolates were separated into green, yellow-green, orange, or red color groups according to the color of the cultures. Total chlorophyll, carotenoid concentration, and percentage of carotenoids in relation to total pigment content were measured for each species. Individual carotenoids of each isolate were identified and quantified. Each color group had pigment characteristics which were distinctive. Other studies on Chlorococcum are discussed in relation to this work. It is proposed that pigmentation of old cultures be used as the first criterion for distinguishing species of Chlorococcum.     

Enteroviral and Mumps Meningitis in Toronto, 1963

Virological investigations of 115 children with the aseptic meningitis syndrome during 1963 resulted in the isolation of enteroviruses from cerebrospinal fluid (CSF) and/or feces of 21 of 48 children who had no association with mumps. For the third successive year, Echo 9 was the dominant enterovirus in cases of aseptic meningitis in Toronto children, but no rashes were associated with Echo 9 meningitis during 1963, in contradistinction to previous years. Mumps virus was isolated from CSF of 25 patients by inoculation of rhesus monkey kidney cultures, and rising or elevated mumps antihemagglutinin titres in paired sera from a further 33 cases provided laboratory evidence of infection with mumps virus in 58 of 67 patients with mumps meningoencephalitis. No enlargement of salivary glands was noted in 20 laboratory-proved cases of mumps meningoencephalitis. Enteroviral meningitis occurred principally during summer, but the peak of mumps meningoencephalitis occurred during late winter.     

Effect of alloxan-diabetes on multiple forms of hexokinase in adipose tissue and lung

Comparison has been made of the effect of alloxan-diabetes on the multiple forms of hexokinase (EC 2.7.1.1) in adipose tissue and lung. Types I and II hexokinase were distinguished in adipose tissue by their different stabilities to heat treatment, which made it possible to determine the activity of each form spectrophotometrically; additional confirmatory evidence was obtained from starch-gel electrophoresis. Type II hexokinase was markedly depressed in adipose tissue from alloxan-diabetic rats. Lung contained types I, II and III hexokinase, type I predominating. There was no significant change in the pattern of these multiple forms of hexokinase in lung from alloxan-diabetic rats. These results are discussed in relation to current ideas that the insulin-sensitivity of a tissue may be correlated with the content of type II hexokinase.     

Influence of hormones on the nicotinamide nucleotide coenzymes of adipose tissue

The concentrations of the oxidized and reduced forms of the nicotinamide nucleotides were measured in the epididymal fat pads of normal, alloxan-diabetic and hypophysectomized rats. In both alloxan-diabetic rats and hypophysectomized rats the weight of the adipose tissue fell, as did the total content of NADH and NADPH; in addition, NAD⁺ was decreased in the alloxan-diabetic group. Of these changes the most marked was in NADPH and this was the only significant difference when the results were expressed as nicotinamide nucleotides/mg. of tissue protein. The concentration of NADPH in the hypophysectomized rats was not altered by treatment with growth hormone but was restored to normal by treatment with thyroxine. These results are discussed in relation to the known effect of these hormonal conditions on lipid synthesis in adipose tissue.     

The activities of nicotinamide mononucleotied adenylyltransferase and of nicotinamide–adenine dinucleotide kinase in the livers of rats subjected to different hormonal treatments

1. The activities of NMN adenylyltransferase and of NAD(+) kinase have been measured in the livers of adrenalectomized or alloxan-diabetic rats and in the livers of rats treated with glucagon, pituitary growth hormone or thyroxine. 2. The activities of these enzymes have been compared with the effects of the same treatments on the nicotinamide nucleotide concentrations in the liver. 3. Alloxandiabetes (+37%) and thyroxine (+27%) both increased the activity of NMN adenylyltransferase. The other treatments were without effect on this enzyme. 4. Only thyroxine increased the activity of NAD(+) kinase significantly (+26%) although both adrenalectomy and glucagon tended to increase its activity. 5. The activity of NAD(+) glycohydrolase was measured in the livers of diabetic rats, and in the livers of rats treated with either growth hormone or thyroxine. Of these treatments, only growth hormone altered the enzyme activity (+26%, calculated on a total hepatic activity basis). 6. Female rats had a greater hepatic NAD(+)-kinase activity than males but there was no sex difference with respect to NMN adenylyltransferase. 7. The lack of correlation between the maximum potential activity of these three enzymes and the known changes of the nicotinamide nucleotides in each of the hormone conditions is discussed.     

Diagnostic and therapeutic efficacy of barium meal examination: a prospective evaluation in general practice.

OBJECTIVE--To assess the efficacy of barium meal examinations in managing patients with dyspepsia in general practice. DESIGN--Prospective study by questionnaires completed by general practitioners before and within three to six months after the barium meal examination. Information was requested about the patients'' symptoms, current treatment, reason for requesting the examination, and the working diagnosis, including degree of certainty and, after the examination, about any change in diagnosis, diagnostic confidence, or management and to determine whether the examination was judged to be helpful or not. SETTING--Inner city health district. PATIENTS--133 Patients with dyspepsia referred by general practitioners for outpatient barium meal examination, 31 of whom failed to attend for the examination, or refused it on arrival, or did not have fully completed questionnaires. Two patients were not available for follow up. MAIN OUTCOME MEASURES--Prevalence of radiological abnormalities and the influence of the examination result on management, particularly changes in drug treatment. RESULTS--Fully completed pairs of questionnaires were available for 100 patients, 58 of whom were aged below 50. Most of the barium meal reports (64) were to confirm the clinical diagnosis; only 22 were to exclude serious disease. Ninety nine patients were already receiving treatment, with 39 taking an H2 receptor antagonist. Fifty eight barium meal examinations showed abnormalities (31 major abnormalities); there were no cancers and in only 18 patients was the working diagnosis changed as a result of the findings. Although the barium meal result increased management confidence (63 patients) and allayed patients'' anxiety (46), changes in management attributed directly to the examination occurred in only 22 patients. Management changes were minor, usually comprising interchange of antacids and H2 receptor antagonists. CONCLUSIONS--Young patients (aged below 50) with dyspepsia are still being overinvestigated. Although barium meal examination improves diagnostic confidence and allays patients'' anxiety, fully utilising communication skills at the initial consultation might allay anxiety more economically.     

Direct and indirect evidence for polypeptide absorption by the teleost gastrointestinal tract

The ability of the gastrointestinal tract of chinook salmon, Oncorhynchus tshawytscha , to absorb polypeptides in vivo was investigated by reference to the appearance of orally administered adrenocorticotropic hormone (ACTH) within the blood of fish previously treated with dexamethasone (3μg g^−l body weight) in order to suppress endogenous ACTH secretion. Further, since cortisol presence within plasma is dependent upon the availability of ACTH, dexamethasone blockade of endogenous ACTH secretion, in conjunction with subsequent measurements of plasma cortisol levels, provides a means by which biological patency of absorbed exogenous ACTH may be demonstrated. Levels of ACTH and cortisol in plasma of dexamethasone-treated salmon were therefore measured for a period of 360 min immediately following oral intubation of ACTH (15μg g⁻¹ body weight). Peak plasma presence of ACTH-like immunoreactivity (676.6 ± 33.6 pg ml⁻¹ plasma) and cortisol (227.1 ± 29.0 ng ml⁻¹ plasma) were recorded 120 min after ACTH administration. Results from the experimental groups were compared to those of 15 control treatments. Since administration of ACTH to chinook salmon elicited a consistent and significant elevation in not only plasma ACTH but also cortisol presence, it is contended that the salmonid gut expresses an ability to absorb polypeptides of dietary origin. The significance of these findings with respect to the oral administration of biologically active peptides and proteins to fish of importance to aquaculture is discussed.