Complex Segmental Duplications Mediate a Recurrent dup(X)(p11.22-p11.23) Associated with Mental Retardation, Speech Delay, and EEG Anomalies in Males and Females

Submicroscopic copy-number variations make a considerable contribution to the genetic etiology of human disease. We have analyzed subjects with idiopathic mental retardation (MR) by using whole-genome oligonucleotide-based array comparative genomic hybridization (aCGH) and identified familial and de novo recurrent Xp11.22-p11.23 duplications in males and females with MR, speech delay, and a peculiar electroencephalographic (EEG) pattern in childhood. The size of the duplications ranges from 0.8–9.2 Mb. Most affected females show preferential activation of the duplicated X chromosome. Carriers of the smallest duplication show X-linked recessive inheritance. All other affected individuals present dominant expression and comparable clinical phenotypes irrespective of sex, duplication size, and X-inactivation pattern. The majority of the rearrangements are mediated by recombination between flanking complex segmental duplications. The identification of common clinical features, including the typical EEG pattern, predisposing genomic structure, and peculiar X-inactivation pattern, suggests that duplication of Xp11.22-p11.23 constitutes a previously undescribed syndrome.     

Synthesis, characterization and deepening in the comprehension of the biological action mechanisms of a new nickel complex with antiproliferative activity

Thiosemicarbazones are versatile organic compounds that present considerable pharmaceutical interest because of a wide range of properties. In our laboratory we synthesised some new metal-complexes with thiosemicarbazones derived from natural aldehydes which showed peculiar biological activities. In particular, a nickel complex [Ni(S-tcitr)₂] (S-tcitr = S-citronellalthiosemicarbazonate) was observed to induce an antiproliferative effect on U937, a human histiocytic lymphoma cell line, at low concentrations (IC₅₀ = 14.4 μM). Therefore, we decided to study the interactions of this molecule with various cellular components and to characterise the induced apoptotic pathway. Results showed that [Ni(S-tcitr)₂] causes programmed cell death via down-regulation of Bcl-2, alteration of mitochondrial membrane potential and caspase-3 activity, regardless of p53 function. The metal complex is not active on G₀ cells (i.e. fresh leukocytes) but is able to induce perturbation of the cell cycle on stimulated lymphocytes and U937 cells, in which a G₂/M block was detected. It reaches the nucleus where it induces, at low concentrations (2.5-5.0 μM), DNA damage, which could be partially ascribed to oxidative stress. [Ni(S-tcitr)₂] is moreover able to strongly reduce the telomerase activity. Although the biological target of this metal complex is still unknown, the reported data suggest that [Ni(S-tcitr)₂] could be a good model for the synthesis of new metal thiosemicarbazones with specific biological activity.     

Free amino acid production during tomato fruit ripening: a focus on l-glutamate

In tomato, free amino acids increase dramatically during fruit ripening and their abundance changed differentially. More evident is l-glutamate which gives the characteristic “umami” flavor. Glutamate is the principal free amino acid of ripe fruits of cultivated varieties. In this paper, we examined the capacity of tomato fruits to process endogenous as well as exogenous polypeptides during the ripening transition, in order to analyze their contribution to the free amino acid pool. In addition, the activity of some enzymes involved in glutamate metabolism such as γ-glutamyl transpeptidase (γ-GTase), glutamate dehydrogenase (GDH), α-ketoglutarate-dependent γ-aminobutyrate transaminase (GABA-T), alanine and aspartate aminotransferases was evaluated. Results showed that peptidases were very active in ripening fruits, and they were able to release free amino acids from endogenous proteins and glutamate from exogenously added glutamate-containing peptides. In addition, red fruit contained enough γ-GTase activity to sustain glutamate liberation from endogenous substrates such as glutathione. From all the glutamate metabolizing enzymes, GDH and GABA-T showed the higher increase in activities when the ripening process starts. In summary, tomato fruits increase free amino acid content during ripening, most probably due to the raise of different peptidase activities. However, glutamate level of ripe fruit seems to be mostly related to GDH and GABA-T activities that could contribute to increase l-glutamate level during the ripening transition.     

Revisiting the question of Neandertal regional variability: a view from the Rhône valley corridor

We compared the dental assemblage of the Rh?ne Valley corridor (RVC) with that of European Neandertals dating to MOIS 7-4 using two linear measurements and three indices. To test if the RVC population was significantly different from Western European Neandertals, we preformed a multi-tiered approached. First, we tested for the normality of the variables using a Shapiro-Wilks test. If the variables were normal, a stepwise Discriminant Function Analysis (DFA) (using Mahalanobis distances) was performed for the normally distributed variables. DFA uses correlation metrics to address weight combinations of variables and emphasizes between group variation while minimizing within group variation. Results show that there is no distinction between the RVC population and other Neandertals except for the Crown Module index of the upper canine. However, the presence of a single significant result does not provide evidence for a local RVC variant within the Neandertal population. These results are supported by evidence from archaeological analysis of this region. We propose that the high genetic control for dental size and shape may account for the reduced ability to distinguish between subpopulation groups based on dental dimensions in groups with small effective size such as the Neandertals.     

Morphological changes in the cephalic salivary glands of females and males of <Emphasis Type="Italic">Apis mellifera</Emphasis> and <Emphasis Type="Italic">Scaptotrigona postica</Emphasis> (Hymenoptera,Apidae)

The cephalic salivary glands of some species of bees are exclusive and well developed only in Apinae. These glands were studied with light and scanning electron microscopy in workers, queens and males from the honey bee Apis mellifera, and the stingless bee Scaptotrigona postica in different life phases. The results show that the cephalic salivary glands are present in females of both the species, and in males of S. postica. Nevertheless, they are poorly developed in young males of A. mellifera. In both species, gland growth is progressive from the time of emergence to the oldest age but, in A. mellifera males, the gland degenerates with age. Scanning electron microscopy shows that the secretory units of newly emerged workers are collapsed while in older workers they are turgid. Some pits on the surface of the secretory units correspond to open intercellular spaces. The possible functions of these glands in females and males of both species are discussed.     

Cloning and purification of recombinant proteins of Mycoplasma hyopneumoniae expressed in Escherichia coli

Mycoplasma hyopneumoniae, the etiological agent of swine enzootic pneumonia, is an important pathogen in the swine industry worldwide. Vaccination is the most cost-effective strategy for controlling and prevention of this disease. However, investigations on pathogenicity mechanisms as well as current serological detection methods and the development of new recombinant subunit vaccines are hampered by the lack of known and well characterized species-specific M. hyopneumoniae antigens. In this work, 54 predicted genes encoding proteins with potential to be used as subunit vaccine or antigens in diagnostic tests were selected, amplified by PCR and cloned into Escherichia coli expression vectors. Recombinant protein expression, solubility and yields were analyzed. The majority of the recombinant proteins were expressed in inclusion bodies. After solubilization with urea or N-lauroyl sarcosine, recombinant proteins were purified by Ni²⁺ affinity chromatography. This approach allowed purification of thirty recombinant M. hyopneumoniae proteins which will be evaluated as vaccine candidates and/or as antigens to be used in diagnostic tests.