FISH analysis of hematological neoplasias with 1p36 rearrangements allows the definition of a cluster of 2.5 Mb included in the minimal region deleted in 1p36 deletion syndrome

Rearrangements in the distal region of the short arm of chromosome 1 are recurrent aberrations in a broad spectrum of human neoplasias. However, neither the location of the breakpoints (BP) on 1p36 nor the candidate genes have been fully determined. We have characterized, by fluorescence in situ hybridization (FISH), the BP in 26 patients with hematological neoplasias and 1p36 rearrangements in the G-banding karyotype. FISH allowed a better characterization of all samples analyzed. Nine cases (35%) showed reciprocal translocations, 15 (58%) unbalanced rearrangements, and two (7%) deletions. We describe two new recurrent aberrations. In 18 of the 26 cases analyzed the BP were located in band 1p36, which is 25.5 Mb long. In 14 of these 18 cases (78%) and without distinction between myeloid and lymphoid neoplasias, the BP clustered in a 2.5 Mb region located between 1p36.32 and the telomere. Interestingly, this region is contained in the 10.5 Mb cluster on 1p36.22-1pter defined in cases with 1p36 deletion syndrome. The 2.5 Mb region, located on 1p36.32-1pter, has a higher frequency of occurrence of tandem repeats and segmental duplications larger than 1 kb, when compared with the 25.5 Mb of the complete 1p36 band. This could explain its proneness for involvement in chromosomal rearrangements in hematological neoplasias.     

Guanosine stimulates neurite outgrowth in PC12 cells via activation of heme oxygenase and cyclic GMP

Undifferentiated rat pheochromocytoma (PC12) cells extend neurites when cultured in the presence of nerve growth factor (NGF). Extracellular guanosine synergistically enhances NGF-dependent neurite outgrowth. We investigated the mechanism by which guanosine enhances NGF-dependent neurite outgrowth. Guanosine administration to PC12 cells significantly increased guanosine 3,5-cyclic monophosphate (cGMP) within the first 24 h whereas addition of soluble guanylate cyclase (sGC) inhibitors abolished guanosine-induced enhancement of NGF-dependent neurite outgrowth. sGC may be activated either by nitric oxide (NO) or by carbon monoxide (CO). -Nitro-l-arginine methyl ester (l-NAME), a non-isozyme selective inhibitor of nitric oxide synthase (NOS), had no effect on neurite outgrowth induced by guanosine. Neither nNOS (the constitutive isoform), nor iNOS (the inducible isoform) were expressed in undifferentiated PC12 cells, or under these treatment conditions. These data imply that NO does not mediate the neuritogenic effect of guanosine. Zinc protoporphyrin-IX, an inhibitor of heme oxygenase (HO), reduced guanosine-dependent neurite outgrowth but did not attenuate the effect of NGF. The addition of guanosine plus NGF significantly increased the expression of HO-1, the inducible isozyme of HO, after 12 h. These data demonstrate that guanosine enhances NGF-dependent neurite outgrowth by first activating the constitutive isozyme HO-2, and then by inducing the expression of HO-1, the enzymes responsible for CO synthesis, thus stimulating sGC and increasing intracellular cGMP.     

Exposure to tobacco smoke and low birth weight: from epidemiology to metabolomics

Introduction: The exposure to tobacco smoke during pregnancy is one of the leading causes of perinatal adverse outcomes such as stillbirth, intrauterine growth restriction (IUGR), and low birth weight, but the underlying biological mechanisms are still unclear. The incidence of this phenomenon maybe largely underestimated since the evaluation is made mainly by self-assessment questionnaires rather than measuring nicotine metabolites (such as cotinine) in biological fluids. In this context metabolomics may be useful to assess the actual number of pregnant women and to highlight the pathophysiological mechanisms that lead to the abovementioned adverse outcomes.

Areas covered: The aims of this review are to analyze the literature and the application of the omics sciences, such as genomics and metabolomics concerning the negative effects of smoking during pregnancy in order to give a comprehensive picture of all the study made so far and to point out the potential of metabolomics as an investigative, predictive, and diagnostic tool.

Expert commentary: Metabolomics in recent years has proved an excellent tool to try to understand the problems in perinatal medicine. With the increase in the number of studies we are convinced that it can be a useful instrument of investigation in this field.     

Two novel PAH gene mutations detected in Italian phenylketonuric patients

We report the identification by denaturing gradient gel electrophoresis and sequence analysis of two new phenylalanine hydroxylase (PAH) gene mutations (IVS4nt-2 and N207S) in single chromosomes of two unrelated Italian phenylketonuric (PKU) patients. Interestingly, mutation Y204C, found on the second mutant allele of family F1, has been previously detected in Chinese patients. Haplotype analysis showed that the latter mutation is linked to the same haplotype (H4) in both Chinese and Italian patients, suggesting a common origin. In vivo assessment of mutation severity indicates that N207S is associated with classic PKU. The identification of these two new mutations further extends the remarkable heterogeneity of the PAH locus in the Italian population. Received: 23 May 1996     

Studies on the antigenic properties of serum albumins

Bovine serum albumin (BSA) is one ofthe most widely studied proteins; its structure iswell known and its antigenic properties have beendescribed in animal models. The aimof our work was to evaluate the role of conformationon antigenicity of serum albumins. This study was performed using electrophoresisassociated with the immunoblotting technique, wheresera from children allergic to BSA were used.Data obtained in this research indicatethat serum albumin antigenicity is only partiallycorrelated to its native three-dimensional structure.Heat treatment and chemical denaturation(SDS treatment) are not able to significantly decrease its capability to bind circulating IgEs. Only thereducing treatment is able to modify the antigenicityof this protein. Moreover, a direct correlationbetween the cross-reactivity observed inimmunoblotting between different serum albumins andthe percentage of their sequence identity(phylogenetic similarity of the species) was shown.     

In Saccharomyces cerevisiae a short amino acid sequence facilitates excretion in the growth medium of periplasmic proteins

In Saccharomyces cerevisiae the cell wall is a barrier to excretion of proteins in the growth medium. Although small proteins are more easily released than bigger ones, other factors besides molecular sieving may play a role in partitioning of periplasmic proteins. By using several complementary approaches including enzyme-activity assays, quantitative immunoblotting on subcellular fractions and growth media, as well as a novel approach involving the use of flow cytometry and specific antibodies, we show that residues 1–8 of mature glucoamylase greatly enhance excretion of both glucoamylase and β-galactosidase in vivo and facilitate extraction of periplasmic proteins in vitro . Immunological data obtained by flow cytometry on whole cells indicate that this amino acid sequence increases the fraction of enzyme reaching the outer cell-wall layers. This amino acid sequence may define a novel type of topogenic sequence, facilitating the crossing of the yeast cell wall in vivo and facilitating extraction of periplasmic proteins by non-disruptive means in vitro .     

Spatial aspects of spontaneous object grouping by young chimpanzees(Pan troglodytes)

I report spontaneous spatial object grouping in five chimpanzees (Pan troglodytes)ranging from 1 to 4 years of age. I recorded subjects' spontaneous interactions with groups of objects, noting the spatial relations in the groupings and the constructive processes that the subjects adopted. Though one subject developed vertical stacks, none of them realized horizontal alignments or spatial correspondences between groups. All subjects showed consistent trends in their constructive processes toward manipulating objects in relation to the body: they increasingly manipulated objects globally, that is to say, they moved or held objects together with the same part of the body. They also increasingly placed objects on the body or in correspondence to their symmetrical body parts. The increasing importance assigned by chimpanzees to body- object relations over object- object relations contrasts with human developmental trends in the domain of manipulative space.     

Fusicoccin and its receptors

Purified preparations of FC receptors from maize, obtained under non-denaturing conditions, showed in SDS-PAGE two doublets of proteins with an apparent molecular mass of 30 and 90 kDa. In this paper the isolation of the 30 kDa protein, its identification as a 14-3-3-like protein, as well as its immunological detection in partially-purified FC-receptor preparations from bean and spinach are described. The 14-3-3 proteins have biochemical properties consistent with potential signalling roles, and their presence in highly purified FC-receptor preparations suggests that they may be involved in FC- signal transduction. Photoaffinity labelling experiments demonstrating that the protein at 90 kDa binds FC are also presented. The evidence presented taken as a whole, suggests the occurrence in maize of a protein complex for FC perception and signal transduction.