Some dermatoglyphic traits in breast carcinoma

The finger and palmar prints of 60 women with breast carcinoma were studied. The results were compared with two groups of healthy women, the first consisted of old women and the second of young women. The dermatoglyphics seem to be of little use in the diagnosis of cancers of ectodermic origin. Supported by M.P.I. 60%, 1983     

Microheterogeneity of lentil seedling (Lens culinaris) amine oxidase

Purified lentil seedling amino oxidase (LSAO) is homogeneous in the analytical ultracentrifuge, but shows heterogeneity in gel-filtration HPLC and in PAGE. Two components were obtained from HPLC and PAGE, but at least 6-7 subforms were seen by electrofocusing techniques. The chromatographic and electrophoretic forms are not interconvertible, indicating the presence of covalent differences. The electrophoretic pattern, but not the chromatographic pattern, is modified by treating the enzyme with a pool of glycohydrolases. The copper-free enzyme shows the same type of heterogeneity as the native enzyme, this ruling out the possibility that some subforms were due to the presence of apoenzyme.     

Polyamine metabolism in hants : Arginine and omithine decarboxylase activity in ripeningTrlticum durum seeds

The pattern of the activity of arginine decarboxylase (ADC) and omithine decarboxylase (ODC) involved in polyamine synthesis in ripening wheat seeds was examined. The aim was to study the polyamines and the activity of the two enzymes in correlation with the growth processes occurring in the developing wheat seeds. The results obtained showed a very different pattern of polyamine content in the two organs of caryopsis, and that the two enzymes in the embryos have a higher activity than in the endosperms. Moreover, while in the embryos the ADC exhibits higher activity than the ODC, in the endosperms the activity of ODC is about similar to that of ADC. This pattern is discussed in relation to the different histological characteristics of embryo and endosperm tissues during seed development.     

Catalytic mechanisms and regulation of lignin peroxidase.

Lignin peroxidase (LiP) is a fungal haemoprotein similar to the lignin-synthesizing plant peroxidases, but it has a higher oxidation potential and oxidizes dimethoxylated aromatic compounds to radical cations. It catalyses the degradation of lignin models but in vitro the outcome is net lignin polymerization. LiP oxidizes veratryl alcohol to radical cations which are proposed to act by charge transfer to mediate in the oxidation of lignin. Phenolic compounds are, however, preferentially oxidized, but transiently inactivate the enzyme. Analysis of the catalytic cycle of LiP shows that in the presence of veratryl alcohol the steady-state turnover intermediate is Compound II. We propose that veratryl alcohol is oxidized by the enzyme intermediate Compound I to a radical cation which now participates in charge-transfer reactions with either veratryl alcohol or another reductant, when present. Reduction of Compound II to native state may involve a radical product of veratryl alcohol or radical product of charge transfer. Phenoxy radicals, by contrast, cannot engage in charge-transfer reactions and reaction of Compound II with H2O2 ensues to form the peroxidatically inactive intermediate, Compound III. Regulation of LiP activity by phenolic compounds suggests feedback control, since many of the products of lignin degradation are phenolic. Such control would lower the concentration of phenolics relative to oxygen and favour degradative ring-opening reactions.     

An inflatable minirhizotron system for root observations with improved soil/tube contact

Commonly used minirhizotrons consisting of a transparent tube inserted into the soil seldom attain good contact between the tube and the soil, which leads to root growth occurring in a gap rather than in the soil. A new system is described involving an inflatable flexible rubber wall, made from a modified motorcycle tube. Pressure ensures a proper tube/soil contact so that the environmental circumstances for root growth along the tube more closely correspond to those in the undisturbed soil. Before the endoscope slide is introduced into the minirhizotron for taking pictures, the inflatable tube is removed, so that there is no-often opaque-wall between the endoscope and the roots. This improves the picture quality and facilitates the analysis of root images.     

Characterization of amine oxidases from pisum, lens, Lathyrus and Cicer

Amine oxidases have been purified to homogeneity from Pisum sativum, Lens esculenta, Lathyrus sativus and Cicer arietinum. The enzymes have a M_r. of 150 000 and are composed of two identical subunits of 72 000. The amine oxidases showed an isoelectrophoretic heterogeneity.     

Oxidation of spermine by an amine oxidase from lentil seedlings

Spermine is a substrate of lentil (Lens culinaris) seedling amine oxidase and the oxidation products are reversible inactivators of the enzyme. The spermine is oxidized at the terminal amino groups to a dialdehyde: 2 moles of hydrogen peroxide and 2 moles of ammonia per mole of spermine are formed. The pH optimum of the enzyme with spermine is 7.9 in TI-HCI buffer; the K_m value is 4.4·10⁻⁴ molar, similar to that found with other substrates (putrescine and spermidine).     

A new dimension to observations in minirhizotrons: A stereoscopic view on root photographs

Summary With a stereoscope, as used for the inspection of aerial photographs, sequential photographs of roots obtained by the endoscope method from minirhizotrons can yield much more information than hitherto. A series of photographs shows that most of the roots seen in a minirhizotron in grassland grew on the surface of the lexan tube, while there was a gap between the roots and the soil. Decay of the extensive root hair zones around the roots may make new root growth in the gap between rhizotron wall and soil invisible. Some consequences of these observations for the endoscope method are discussed.     

Founder effect in a Belgian-Dutch fragile X population

For many years, the high prevalence of the fragile X syndrome was thought to be caused by a high mutation frequency. The recent isolation of the FMR1 gene and identification of the most prevalent mutation enable a more precise study of the fragile X mutation. As the vast majority of fragile X patients show amplification of an unstable trinucleotide repeat, DNA studies can now trace back the origin of the fragile X mutation. To date, de novo mutations leading to amplification of the CGG repeat have not yet been detected. Recently, linkage disequilibrium was found in the Australian and US populations between the fragile X mutation and adjacent polymorphic markers, suggesting a founder effect of the fragile X mutation. We present here a molecular study of Belgian and Dutch fragile X families. No de novo mutations could be found in 54 of these families. Moreover, we found significant (P < 0.0001) linkage disequilibrium in 68 unrelated fragile X patients between the fragile X mutation and an adjacent polymorphic microsatellite at DXS548. This suggests that a founder effect of the fragile X mutation also exists in the Belgian and Dutch populations. Both the absence of new mutations and the presence of linkage disequilibrium suggest that a few ancestral mutations are responsible for most of the patients with fragile X syndrome.     

A case of D13 ring chromosome

Summary A case of D ring chromosome identified with trypsin banding as a 13 with loss of the bands p12 and q34 is reported. The clinical features characteristically associated with the loss of these specific segments were present.