Serum ceruloplasmin as a marker in prostate cancer.

AIM: Serum acid phosphatase and prostate specific antigen have been utilized as disease markers in prostate cancer, one of the commonest cancers of the elderly. Serum ceruloplasmin (Cp) increases in cancer patients; it may be a reliable marker for prostate cancer, but few data are available on specificity and sensitivity of Cp values. METHODS: Serum prostate specific antigen (PSA) and Cp was determined in Greek patients suffering from histologically proven prostate carcinoma or benign hyperplasia. The results were compared with those in controls matched for sex and age. RESULTS: In all studied subjects with a prostate cancer, serum Cp values were higher than age-matched healthy controls; they were also higher in cases with benign hyperplasia. No difference in serum Cp was noted among patients with earlier and advanced stages of the tumor. No difference in Cp was also found between benign hyperplasia and normal controls. There exists a significant difference in serum PSA between both prostate cancer and benign hyperplasia cases. There exists also a difference between benign hyperplasia cases and controls. CONCLUSION: It is suggested that serum Cp may complement the biochemical screening in prostate carcinoma, especially in cases where this cancer is not accompanied by elevation of serum PSA. However, it is not of help in differentiating prostate cancer from prostate benign hyperplasia.

Detection of TT virus in lymph node biopsies of B-cell lymphoma and Hodgkin's disease, and its association with EBV infection.

Human TT virus (TTV) recently isolated from the serum of a patient with post-transfusion hepatitis does seem to have only hepatopathic effect. The virus can also infect the serum, peripheral blood mononuclear cells (PBMC) and bone marrow cells (BMC ). Additional evidence has indicated that TTV is also present in the serum of people with hematopoietic malignancies. A significant increase in the incidence of lymphoma has recently been observed worldwide. We have investigated the presence of TTV DNA in lymph node biopsies of Italian patients affected with the most common lymphoma types in Western Countries: follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL) and nodular sclerosis Hodgkin's disease (NS-HD). The possible role of a co-infection with Epstein-Barr virus (EBV) has also been investigated. DNA was extracted from 73 paraffin-embedded and 38 snap-frozen tissue specimens. From these, only 67 samples (29 paraffin-embedded and 38 snap-frozen tissues) from a total of 56 patients, were suitable for PCR analysis. TTV and EBV were detected by PCR using primers from two different conserved region in TTV and EBV genomes respectively. TTV DNA was detected in 30.0-50.0% of FL, 30.8% of DLBCL and 30.0-50.0% of NS-HD cases, depending on the primers used. All cases of non-specific reactive lymphoid hyperplasia (RLH), used as a putative control, were negative. The two major TTV genotypes circulating in Italy (G1 and G2) were detected in the analysed lymphoid neoplasms. EBV DNA was detected in 40.0% of FL, in 72.7%of DLBCL, in 80.0% of SN-HD and in 40.0% of RLH cases. EBV co-infection was found in 90% of TTV positive cases. The in situ hybridization assay was performed in TTV positive frozen samples. The significant prevalence of TTV DNA in lymphocytes circulating in the lymph nodes of both B-cell lymphomas and HD reported herewith suggests an implication of TTV infection in the development of these lymphoproliferative disorders.

Prediction of lipid accumulation-degradation in oleaginous micro-organisms growing on vegetable oils.

Oleaginous micro-organisms (yeasts, moulds), in culture media having the carbon source as limited factor, degrade reserve lipids and produce new biomass, after the onset of carbon exhaustion from the medium. In this paper the process of lipid accumulation-degradation in oleaginous micro-organisms, growing on a vegetable oil was simulated. The model was integrated with 4 different methods and the parameters were optimised with the least squares method. It was found that the degradation of endocellular carbon pool is a very slow process characterised, however, by a good yield in fat-free biomass. Low values of the specific growth rates of the fat-free microbial mass, both from consumption of extracellular and endocellular carbon pools, favourite the production of microbial lipid. The maximum of the specific rate of lipid accumulation is positively affected by the low values of the specific growth rate of the fat-free microbial mass from consumption of extracellular carbon pool, but remained unaffected by the specific growth rate of the fat-free microbial mass from consumption of endocellular carbon pool. On the other hand, lipid production and specific rate of lipid accumulation are positively influenced by the high values of the specific rate of storage lipid formation. In conclusion, this numerical model can be used in the laboratory as pilot for planing further experimental work.

Accuracy of phylogenetic trees estimated from DNA sequence data.

The relative merits of four different tree-making methods in obtaining the correct topology were studied by using computer simulation. The methods studied were the unweighted pair-group method with arithmetic mean (UPGMA), Fitch and Margoliash's (FM) method, thd distance Wagner (DW) method, and Tateno et al.'s modified Farris (MF) method. An ancestral DNA sequence was assumed to evolve into eight sequences following a given model tree. Both constant and varying rates of nucleotide substitution were considered. Once the DNA sequences for the eight extant species were obtained, phylogenetic trees were constructed by using corrected (d) and uncorrected (p) nucleotide substitutions per site. The topologies of the trees obtained were then compared with that of the model tree. The results obtained can be summarized as follows: (1) The probability of obtaining the correct rooted or unrooted tree is low unless a large number of nucleotide differences exists between different sequences. (2) When the number of nucleotide substitutions per sequence is small or moderately large, the FM, DW, and MF methods show a better performance than UPGMA in recovering the correct topology. The former group of methods is particularly good for obtaining the correct unrooted tree. (3) When the number of substitutions per sequence is large, UPGMA is at least as good as the other methods, particularly for obtaining the correct rooted tree. (4) When the rate of nucleotide substitution varies with evolutionary lineage, the FM, DW, and MF methods show a better performance in obtaining the correct topology than UPGMA, except when a rooted tree is to be produced from data with a large number of nucleotide substitutions per sequence.(ABSTRACT TRUNCATED AT 250 WORDS)

Relative efficiencies of the maximum parsimony and distance-matrix methods in obtaining the correct phylogenetic tree.

The relative efficiencies of the maximum parsimony (MP) and distance-matrix methods in obtaining the correct tree (topology) were studied by using computer simulation. The distance-matrix methods examined are the neighbor-joining, distance-Wagner, Tateno et al. modified Farris, Faith, and Li methods. In the computer simulation, six or eight DNA sequences were assumed to evolve following a given model tree, and the evolutionary changes of the sequences were followed. Both constant and varying rates of nucleotide substitution were considered. From the sequences thus obtained, phylogenetic trees were constructed using the six tree-making methods and compared with the model (true) tree. This process was repeated 300 times for each different set of parameters. The results obtained indicate that when the number of nucleotide substitutions per site is small and a relatively small number of nucleotides are used, the probability of obtaining the correct topology (P1) is generally lower in the MP method than in the distance-matrix methods. The P1 value for the MP method increases with increasing number of nucleotides but is still generally lower than the value for the NJ or DW method. Essentially the same conclusion was obtained whether or not the rate of nucleotide substitution was constant or whether or not a transition bias in nucleotide substitution existed. The relatively poor performance of the MP method for these cases is due to the fact that information from singular sites is not used in this method. The MP method also showed a relatively low P1 value when the model of varying rate of nucleotide substitution was used and the number of substitutions per site was large. However, the MP method often produced cases in which the correct tree was one of several equally parsimonious trees. When these cases were included in the class of "success," the MP method performed better than the other methods, provided that the number of nucleotide substitutions per site was small.

The phylogeny of nine species of the Drosophila obscura group inferred by the banding homologies of chromosomal regions. I. Element B.

The phylogenetic relationships among nine Drosophila species belonging to the obscura group were investigated by establishing the segments displaying banding homologies in their element B (equivalent to the U element of D. subobscura). The phylogenetic ordering of the species was accomplished using overlapping inversions. Two African species, D. kitumensis and D. microlabis, were investigated. These species are homosequential for their element B gene arrangement but differ from that of D. obscura by several rearrangements. Drosophila obscura seems to be most closely related to D. subsilvestris, from which the respective element B gene arrangements differ at least by six inversions. Three species, D. obscura, D. ambigua, and D. tristis, are closely related and form a cluster. Drosophila obscura displays an element B polymorphism for a pericentric inversion for which D. ambigua is fixed for one gene arrangement and D. tristis for the other. Both D. ambigua and D. tristis share a short distal inversion in the small arm of the chromosome, and differ in this respect from D. obscura. Drosophila madeirensis, D. guanche, and D. subobscura all share the same element B gene arrangement, which is acrocentric, but metacentric in all the other species mentioned. It was found that the gene arrangements of the species from the obscura cluster seem to occupy an intermediate position between those of the species of the D. subobscura cluster and those of the African one. The data reported generally are in good agreement with information provided in the literature.

Iron stores in multi-transfused thalassaemic patients seem not to be influenced by the HLA system.

The HLA-A and -B antigens of 99 Greek patients with transfusion dependent homozygous beta thalassaemia were determined. The HLA antigen distribution in thalassaemic patients with a severe transfusion siderosis and in patients without signs of siderosis were compared to that of 400 healthy unrelated controls from the same population. There is an increase of HLA-B 14 antigen in both groups of thalassaemics as compared with the controls. No significant difference exists in the distribution of all the other HLA antigens between the two sub-groups of thalassaemics or with the controls.