Effect of cadmium on photosynthetic pigments in synchronously growing Chlorella cells

Cadmium ions introduced at concentration of 30 ppm to the cultivation medium of synchronously growing Chlorella vulgaris decreased concentration of chlorophylls a and b, carotenes alpha and beta and lutein at various stages of the cell cycle, while at concentration of 1 ppm synthesis of the photosynthetic pigments was stimulated. The pigment content in the cadmium treated cells was related to the morphometrically determined changes in the size and shape of the cells.     

Endocrine cells of the mucous membrane of the fundus region of the stomach of hibernating rodents]

The gastric mucous membrane was studied in the hibernating animal Citellus erythrogenys in different seasons (during 7-8 months a year the animal is in hibernation and its digestive tract is not functioning). During hibernation the general amount of enterochromaffin-like cells decreases and their composition changes: the number of active cells diminishes and that of less active cells grows. Such dynamics of cells suggests the participation of enterochromaffin-like cells of Citellus erythrogenys in the regulation of gastric secretion (in rats and mice these cells contain histamine stimulating the mucous membrane glands). The amount of true enterochromaffin cells is not sufficiently changed and they seem to be not directly related with digestion but to be producers of serotonin which (together with serotonin of the brain) takes part in sustaining the mechanisms of appearance and supporting of winter hibernation.     

Multiple sclerosis; its frequency and distribution,with special reference to San Francisco

Epidemiologic surveys of multiple sclerosis were conducted in 1949 in San Francisco, Winnipeg, Boston, New Orleans, and Denver. Reports of cases for 1939 through 1948 were obtained from record offices, hospitals and clinics, and private physicians. The basis for the observations was the group of "probable" cases among residents. In San Francisco these probable cases in residents numbered 415; however, in only 146 of these was the onset between 1939 and 1948. Of the 143 patients who were white, 51 were male and 92 female. The average annual incidence based on these figures was 2.1 per 100,000-1.5 for males and 2.6 for females.Prevalence, based on probable cases in residents on January 1, 1949, was 29.7 cases per 100,000 population-21.2 for males and 38.1 for females. Mortality was 0.7 per 100,000 population-0.9 for females and 0.6 for males. In comparison of the findings for San Francisco with those of other cities, both the incidence and the severity of the disease appear to decrease from north to south.     

Viral and Bacterial Pathogens in Bovine Respiratory Disease in Finland

Pathogens causing bovine respiratory tract disease in Finland were investigated. Eighteen cattle herds with bovine respiratory disease were included. Five diseased calves from each farm were chosen for closer examination and tracheobronchial lavage. Blood samples were taken from the calves at the time of the investigation and from 86 calves 3–4 weeks later. In addition, 6–10 blood samples from animals of different ages were collected from each herd, resulting in 169 samples. Serum samples were tested for antibodies to bovine parainfluenza virus-3 (PIV-3), bovine respiratory syncytial virus (BRSV), bovine coronavirus (BCV), bovine adenovirus-3 (BAV-3) and bovine adenovirus-7 (BAV-7). About one third of the samples were also tested for antibodies to bovine virus diarrhoea virus (BVDV) with negative results. Bacteria were cultured from lavage fluid and in vitro susceptibility to selected antimicrobials was tested. According to serological findings, PIV-3, BAV-7, BAV-3, BCV and BRSV are common pathogens in Finnish cattle with respiratory problems. A titre rise especially for BAV-7 and BAV-3, the dual growth of Mycoplasma dispar and Pasteurella multocida, were typical findings in diseased calves. Pasteurella sp. strains showed no resistance to tested antimicrobials. Mycoplasma bovis and Mannheimia haemolytica were not found.     

Highlights in Biocatalysis – Historical Landmarks and Current Trends

Biocatalysis has ancient roots, yet it is developing into a key tool for synthesis in a wide range of applications. Important events in the history of enzyme technology from the 19^th century onwards are highlighted. Considering the most relevant progress steps, the production of penicillanic acid and the impact of genetic engineering are traced in more detail. Applied biocatalysis has been defined as the application of a biocatalyst to achieve a desired conversion selectively, under controlled, mild conditions in a bioreactor. Biocatalysts are currently used to produce a wide range of products in the fields of food manufacture (such as bread, cheese, beer), fine chemicals (e.g., amino acids, vitamins), and pharmaceuticals (e.g., derivatives of antibiotics). They not only provide access to innovative products and processes, but also meet criteria of sustainability. In organic synthesis, recombinant technologies and biocatalysts have greatly widened the scope of application. Examples of current applications and processes are given. Recent developments and trends are presented as a survey, covering new methods for accessing biodiversity with new enzymes, directed evolution for improving enzymes, designed cells, and integrated downstream processing.