Glycogen metabolism in the genus Neisseria: synthesis from sucrose by amylosucrase

Eight strains (seven species) of Neisseria were found to possess intracellular amylosucrases capable of synthesizing glycogen directly from sucrose. All eight systems were stimulated by primer glycogen, possessed similar kinetic parameters, and were competitively inhibited to similar degrees by fructose. The enzymes bound tightly to their polysaccharide products but these complexes could be readily dissociated by polyacrylamide gel electrophoresis. Some of the enzyme-product complexes appeared to be virutally free of contaminating proteins.     

Prevalence of Cytomegalovirus Infection in a Normal Urban Population in Nova Scotia

During 1967 and 1968 a seroepidemiological survey was conducted on the prevalence of CF antibodies to CMV in the normal population of the Halifax-Dartmouth metropolitan area of Nova Scotia. Samples of 550 sera, collected from all age groups, including newborns, were processed. At birth, 34% of infants possess antibodies, presumably of maternal origin, and there follows a decline until at 2 years of age only 4% of children exhibit evidence of infection. There is a gradual increase up to 16% by 20 years of age, and thereafter this is maintained until by 40+ years half the population possesses antibodies.A more detailed analysis of cord sera indicated that approximately 60% of women of childbearing age possess no antibodies and are susceptible to primary CMV infection. Among these, age and gravidity are not significant factors.These data indicate that CMV infection is fairly widespread in this community, although comparative studies suggest that it is less so than in some other areas, such as Easter Island, where a more homogeneous pattern of overcrowding and poor sacioeconomic conditions prevails.     

The hepato-renal syndrome in cultured turbot (Scophthalmus maximus L.)

The histopathology of biliary hyperplasia and renal calcinosis, associated with infections of two parasites, Myxidium incurvatum and Rhabdospora thelohani , is described in turbot, Scophthalmus maximus (L.), from Scottish marine fish farms and wild populations. Liver and kidney lesions were divided into four, and parasite infections into five grades of severity. A few of the fish examined were not parasitized, but every one showed some evidence of pathological change, even the apparently normal individuals from all populations. Although there is a positive association between the parasitic and pathological data, parasitism is not considered to be the principal cause of either the hepatic or renal lesion; the evidence suggests rather a secondary opportunist role for the parasites. The general severity of the condition in captive stocks suggests that the cause may lie in the fundamentals of present techniques of turbot husbandry, but no specific agent has been identified. A case is put forward for considering Rhabdospora to be a parasite rather than a specialized host cell.     

Organization of the 5S rRNA genes in the soybean Glycine max (L.) Merrill and conservation of the 5S rDNA repeat structure in higher plants

The 5S rRNA gene of the soybean Glycine max (L.) Merr. has been cloned on a 556-bp fragment of DNA and sequenced. This fragment contains two copies of the soybean 5S rDNA sequence, one intact and one truncated, separated by noncoding DNA. We have used this clone to investigate the organization of the 5S genes within the soybean genome and the extent of their methylation. Our results demonstrate that soybean 5S genes are clustered, organized into tandem repeats of 330 bp, and extensively methylated. Hybridization of the 5S sequence to Southern transfers of soybean DNA digested with BamHI reveals a striking ladderlike pattern. Hybridization of the soybean 5S sequence to a wide variety of plant DNAs results in similar patterns, suggesting that the 5S rDNA sequence, gene organization, and methylation pattern are conserved in many higher plants.     

Phycocyanin synthesis and degradation in the blue-green bacterium Anacystis nidulans.

Cellular content and rates of synthesis of the apoprotein subunits of phycocyanin in Anacystis nidulans cultures undergoing, and recovering from, nitrate starvation were measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of total and immunoprecipitable soluble proteins. Results indicated that (i) nitrate starvation provokes coordinate degradation of apoprotein subunits: (ii) de novo synthesis of these subunits is selectively depressed during starvation; (iii) nitrate restoration provokes coordinate increases in the rates of synthesis of these subunits, although maximal rates are not achieved for 6 to 10 h after readdition of nitrate; and (iv) illumination affects both relative and absolute rates of apoprotein formation.     

Early-stage Hodgkin's disease: current approaches to treatment.

Most patients with early-stage Hodgkin''s disease can now be cured by one of several therapeutic approaches. This review highlights the developments in the diagnosis and treatment of the disease that have led to long-term survival rates greater than 90%. Past and present radio-therapy (RT) planning and treatment practices are discussed in the context of both clinical and pathological staging. The role of initial bimodal therapy (RT and chemotherapy [CT]) and the use of CT in patients who suffer relapse after initial treatment with RT alone are reviewed. On the basis of prognostic factors, subgroups of patients for whom bimodal therapy is recommended, including those with a bulky mediastinal mass, have now been identified. Although treatment is highly successful, debilitating consequences of RT and CT, such as infertility, infection and second malignant diseases, remain. Newer treatment regimens may reduce morbidity and have similar or better long-term results with respect to survival and quality of life.