Vimentin and 70K Neurofilament Protein Co-exist in Embryonic Neurones from Spinal Ganglia

Abstract: The mesenchymal intermediate filament protein vimentin and the 70K component of neurofilament were detected by two-dimensional gel electrophoresis in cultures of pure sensory and sympathetic neurones derived from chick embryos. The identities of these neuronal intermediate filament proteins were confirmed by comparison of their molecular weights, isoelectric points, and peptide patterns from limited papain digestions with those of the corresponding proteins from fibroblasts and brain, respectively. A specific antibody to vimentin stained filamenteous structures and colcemid-induced coils in both neurones and associated satellite cells. In contrast, a specific antibody to the 70K neurofilament protein stained these structures solely in neurones. This neurone-specific staining, as well as its molecular weight and isoelectric point, distinguishes the 70K neurofilament protein from the 68K neurofilament as sociated protein described by others, which has been claimed to resemble the tubulin assembly protein.     

Brain Regional Distribution of Glutamic Acid Decarboxylase, Choline Acetyltransferase, and Acetylcholinesterase in the Rat: Effects of Chronic Manganese Chloride Administration after Two Years

Abstract: Rats were treated chronically with manganese chloride from conception onward for a period of over 2 years in order to study the effects of manganese and aging on the activities of glutamic acid decarboxylase (GAD), choline acetyltransferase (ChAT), and acetylcholinesterase (AChE) in hypothalamus, cerebellum, pons and medulla, striatum, midbrain, and cerebral cortex (which included the hippocampus). Manganese-treated 2-month-old and 24- to 28-month-old rats and age-matched controls were studied. In control rats during aging the activities of GAD decreased in hypothalamus (19%), pons and medulla (28%), and midbrain (22%) whereas the activities of AChE decreased in all regions (20–48%), particularly in the striatum (44–48%). Changes in ChAT activities in aging were observed only in one region—a decrease (23%) in the striatum. Life-long treatment with manganese appeared to abolish partially the decreases in aging in AChE activities in hypothalamus, cerebellum and striatum, and striatal ChAT activity. Manganese treatment also seemed to abolish the age-related decreases in GAD activities, since GAD activities in various brain regions of manganese-treated senescent rats were not significantly different from those of control young rats. These results are discussed in relation to other metabolic changes associated with aging and manganese toxicity.     

Computer control of fermentation processes

A review of computer control of fermentation processes is presented. Hardware and software technologies that have been used to implement computer control are discussed. This includes instrumentation, interfacing techniques, computer hardware configurations, data logging and documentation, displays and man-machine interaction, low-level control, back-up and error detection and programming techniques. Advanced control of fermentation processes with the utilization of modern control techniques is also presented. This topic is divided into steady state optimization and dynamic optimization. Finally, on-line estimation of bioreactor parameters for feedback control is presented.     

‘Complete’ trisomy 5p; de novo translocation t(2;5)(q36;p11) with isochromosome 5p

Summary A case of complete trisomy 5p due to a de novo translocation t(2;5)(q36;p11) with an isochromosome 5p is described. Complete trisomy 5p has been reported only once (Brimblecombe et al., 1977). The confusing literature relating to partial trisomy 5p is reviewed. Comparison of our case with the patients reported by Brimblecombe et al. (1977) and by Opitz and Patau (1975) is suggestive for a distinct clinical syndrome if (almost) the complete short arm of chromosome 5 is present in a trisomic state. Unfortunately the clinical findings in the case of Brimblecombe (1966, 1977) are poorly documented. The main features of this syndrome are: macrocephaly, psychomotor retardation, hypotonia, postnatal growth failure, tracheobronchial involvement, mongoloid slant of the eyes, epicanthus, low-set ears, depressed nasal bridge, short first toe, and seizures.     

Trichinella spiralis: changes caused in the mouse's thymic, splenic, and lymph node cell populations.

Infections with the nematode Trichinella spiralis induce unresponsiveness in mice. A study was made to determine whether suppression could be due to a deficiency in the cells responsible for the immunological response. Mice were given low or moderate infections and were killed 7, 14, 28, or 56 days after inoculation; spleen macrophages and leucocytes, θ cells, and Con A- and LPS-sensitive cells were determined in the thymus, spleen, and the mesenteric and axillary lymph nodes. Spleen macrophages are diminished throughout the course of the infection, reaching significantly low levels on the 14th day. The thymus loses, whereas the spleen and the axillary node gain, cells bearing the θ antigen. In spite of the increase in leucocytes and θ cells in the secondary lymphoid tissue, the cells of these organs are insensitive to the blastogenic action of Con A in the heavier infections. In lower infections, however, spleen cells show an enhanced response to Con A and LPS; mesenteric cells, on the other hand, show an early enhanced susceptibility to LPS and a reduced susceptibility to Con A and, in the later phases of parasitism, an enhanced Con A and a reduced LPS susceptibility. It is suggested that these phenomena contribute to the immunosuppression phenomena which are characteristic of T. spiralis infections.     

Apoproteins of human serum high density lipoproteins. Isolation and characterization of the peptides of Sephadex fraction V from normal subjects and patients with abeta-lipoproteinemia.

1. Sephadex fraction V, obtained from human serum high density lipoprotein apoprotein (HDL apoprotein) of normal subjects and of patients with abetalipoproteinemia, was resolved by DEAE-cellulose ion exchange column chromatography into several fractions which were defined in terms of amino acid composition, NH2- and COOH-terminsls, sialic acid content, immunologic and electrophoretic properties, and in vitro activation of purified lipoprotein lipase from rat adipose tissue. 2. Fraction V of HDL apoprotein of both normal and abetalipoproteinemic subjects was found to contain polypeptides corresponding to apolipoproteins C-I, C-II, C-III-1, and C-III-2, which had been described previously in very low-density lipoproteins (VLDL). The content of apo C-III-1 in abetalipoproteinemia-HDL was very low, whereas the percentage, by weight, of apo C-I was about twice as high as that in the normal subjects studied. Furthermore, both normal and abetalipoproteinemia-HDL apoprotein contained a previously unreported peptide which had a molecular weight of about 7 000 and electrophoretic, chemical, and immunological properties distinct from those of the known C apolipoproteins. Of all of the peptides comprising fraction V, only apo C-II activated a purified preparation of rat adipose tissue lipoprotein lipase. This was the case for both normal and abetalipoproteinemic subjects.     

The influence of pretreatment with exogenous DNA on the frequencies of aberrations induced by X-Rays

Pretreatment with calf thymus DNA decreases the frequency of chromosomal aberrations in metaphases and anaphases induced by X-rays in barley root meristem cella. This effect is manifested in a wide range of concentrations (5% -0.001%) without any great dependence on the concentration. Calf thymus DNA alone does not induce any chromosomal aberrations in barley root meristem cells.     

Studies on resistance in snails: Specific resistance induced by irradiated miracidia of Echinostoma lindoense in Biomphalaria glabrata snails

In juvenile Biomphalaria glabrata snails exposed to irradiated Echinostoma lindoense miracidia, the sporocysts migrated to the heart at the same speed as did nonirradiated sporocysts in control snails. However, in each snail so exposed to irradiated miracidia, amebocyte clumps in the snail's heart destroyed the sporocysts within 2–9 days post-exposure. This process induced a strong, highly specific resistance to homologous reinfection in these previously susceptible snails. The snails remained susceptible to Schistosoma mansoni and Paryphostomum segregatum (Echinostomatidae), but were partially resistant to Echinostoma paraensei and E. liei, two echinostome species closely related to E. lindoense.     

Studies on the Malayan forest rat filaria, Breinlia booliati: periodicity and microfilaraemic patterns during the course of infection.

Breinlia booliati exhibited nocturnal subperiodicity in its natural host, Rattus sabanus in contrast to experimentally infected laboratory-reared albine rats which showed irregular fluctuations of microfilariae throughout the 24 hour cycle. All the infected albino rats showed a prepatent period between 11-14 weeks postinoculation. Three patterns of microfilaraemia were discerned during the course of infection 38/49 rats displayed a single peak, 4/49 displayed 2 peaks about 12-15 weeks apart and 7/49 showed a sustained high plateau-like pattern of microfilaraemia. Cortisone had no effect on microfilarial levels when administered to rats near postpatency and some at postpatency.