Isolation and characterization of polymorphic nuclear microsatellite loci in Pinus cembra L.

We developed eight polymorphic nuclear microsatellite markers for the Swiss stone pine (Pinus cembra L.), of which seven may be amplified in a multiplex polymerase chain reaction. Allelic polymorphism across all loci and 40 individuals representing two populations in the Swiss Alps was high (mean = 7.6 alleles). No significant linkage disequlibrium was displayed between pairs of loci. Significant deviation from Hardy-Weinberg equilibrium was revealed at three loci in one population. Cross-amplification was achieved in two related species within the genus (P. sibirica and P. pumila). Thus, the markers may be useful for population genetic studies in these three pine species. They will be applied in ongoing projects on genetic diversity and patterns of gene flow in P. cembra.

Studies on immunoregulatory mechanisms in acute and chronic hepatitis B.

Patients with acute hepatitis B and HBV-induced chronic hepatitis as well as normal control persons participated in the study. Hepatitis patients of both groups have decreased OKT4+/OKT8+T cell ratios due to an percental increase of OKT8+T cells in peripheral blood compared to the data of controls. Lymphocyte cultures of chronic hepatitis patients show reduced DNA synthesis after stimulation by allogeneic non-T cells, PHA, Con A and PWM. PWM-induced immunoglobulin secretion by B cells, determined by means of a reverse haemolytic plaque assay (RHPA) and a solid phase ELISA, showed comparable results in hepatitis B patients and controls. The AMLR, which is thought to reflect an autologous immunoregulatory phenomenon, is slightly impaired in cultures of hepatitis B patients in comparison to controls. Con A-induced suppressor cell activity on T cell reactions is decreased in hepatitis, whereas suppressor cell activity on B cell activation is within the same range as in cultures of controls. It is concluded from these data, that suppressor cell activity on T cell function is impaired in hepatitis B, whereas B cell functions and suppressor cell activity on B cell function are in the normal range. The results with the functional assays and the finding of increased proportions of OKT8+T cells in hepatitis B are considered to reflect properties of different T cell subpopulations, responsible for different immunoregulatory functions.

[Tryptic and chymotryptic activity in the faeces of children of different age groups (author's transl)]. / Tryptische und chymotryptische Aktivität im Stuhl von Kindern verschiedener Altersgruppen

Measurement of tryptic and chymotryptic activity in the faeces was not disturbed by bacterial proteolytic activity of different bacteria such as proteus, pseudomonas, coli, enterococci, bacteroides. Both activities within a group follow a logarithmic normal distribution. Lower limit of the standard deviation is 51% upper limit 129% for tryptic activity, respectively 60 and 170% for chymotryptic activity. There were no differences in chymotryptic activity between the 10 age groups comprising 157 healthy children, whereas a significant difference could be found for tryptic activity between premature and older children. Daily fluctuations of the enzyme activities are quite high in the same individual, and only reduced in "bottlefed" infants with constant nutrition. In prematures and very young infants chymotryptic activity predominates, later tryptic activity. Influence of increased and decreased bowel movements on deviation of the data was tested. There was, however, no real alteration of enzyme activity due to the bowel dysfunction beyond the standard deviation of the control groups. But passage time and nutrition have to be considered beside other factors in the wide distribution of the enzyme activities and the latter limits the value of this method.