Metabolism of amphibian spermatozoa in relation to their motility.

Bufo arenarum spermatozoa were able to sustain motility both under aerobic and anaerobic conditions. In aerobiosis, the oxygen consumption varies between 2.6 and 4.2 microliter O2/10(8) cells/h at 30 degree C. The synthesis of lactic acid by anaerobic spermatozoa demonstrated the existence of an active glycolytic pathway.     

On trend extraction models: Interpretation,empirical evidence and forecasting performance

This paper deals with the economic interpretation of the unobserved components model in the light of the apparent problem posed by previous work in that several practiced methodologies seem to lead to very different models of certain economic variables. A detailed empirical analysis is carried out to show how the failure in obtaining quasi-orthogonal components can seriously bias the interpretation of some decomposition procedures. Finally, the forecasting performance (in both the short and long run) of these decomposition models is analyzed in comparison with other alternatives.     

Effect of carbon tetrachloride poisoning on the plasma levels of aspartate-aminotransferase isoenzymes in the rat

Riassunto Mediante frazionamento cromatografico su colonna di resina a scambio anionico, abbiamo potuto documentare nel siero di ratti intossicati con dosi diverse di CCl₄, incrementi assai significativi sia della componente mitocondriale che citoplasmatica della aspartato-aminotransferasi.     

Hsp70: a carrier molecule with built-in adjuvanticity

One problem associated with the development of subunit vaccines is their limited immunogenicity, due to their physico-chemical structure, their inability to encounter the correct MHC restriction element, or the need for strong adjuvants to be delivered along with them. These problems are usually solved by conjugating target epitopes (peptides or oligosaccharides) with carrier proteins which provide a source of T-cell epitopes recognised by a large proportion of the vaccinated individuals. We have shown that mycobacterial hsp65 and hsp70 exert a strong helper effect in vivo when conjugated to synthetic peptides or oligosaccharides. Interestingly, this helper effect did not require the need for any adjuvant, either in mice or in monkeys. The helper effect mediated by the hsp65 required that animals were previously primed with either live BCG or the hsp65 alone; on the other hand, such a priming was not required when the hsp70 was used in the conjugates. Similar results were obtained with HSP molecules fromEscherichia coli. This may suggest that the adjuvant-free helper effect observed applies not only to mycobacterial HSP, but also to HSP from other prokaryotes. These findings suggest that microbial hsp70 could be considered for the design of conjugated vaccine constructs for eventual human use.     

La Rigenerazione del testicolo atrofico da Fluoroacetamide

Summary Morphological changes of atrophic testis, obtained by treating normal rats with fluoroacetamide, are studied at various times after treatment. The data show that the testicular germinal epithelium is fully regenerated 165 days after treatment.     

GSK3 and β-catenin determines functional expression of sodium channels at the axon initial segment

Neuronal action potentials are generated through voltage-gated sodium channels, which are tethered by ankyrinG at the membrane of the axon initial segment (AIS). Despite the importance of the AIS in the control of neuronal excitability, the cellular and molecular mechanisms regulating sodium channel expression at the AIS remain elusive. Our results show that GSK3α/β and β-catenin phosphorylated by GSK3 (S33/37/T41) are localized at the AIS and are new components of this essential neuronal domain. Pharmacological inhibition of GSK3 or β-catenin knockdown with shRNAs decreased the levels of phosphorylated-β-catenin, ankyrinG, and voltage-gated sodium channels at the AIS, both “in vitro” and “in vivo”, therefore diminishing neuronal excitability as evaluated via sodium current amplitude and action potential number. Thus, our results suggest a mechanism for the modulation of neuronal excitability through the control of sodium channel density by GSK3 and β-catenin at the AIS.     

Identification of the gene altered in Berardinelli-Seip congenital lipodystrophy on chromosome 11q13

Congenital generalized lipodystrophy, or Berardinelli-Seip syndrome (BSCL), is a rare autosomal recessive disease characterized by a near-absence of adipose tissue from birth or early infancy and severe insulin resistance. Other clinical and biological features include acanthosis nigricans, hyperandrogenism, muscular hypertrophy, hepatomegaly, altered glucose tolerance or diabetes mellitus, and hypertriglyceridemia. A locus (BSCL1) has been mapped to 9q34 with evidence of heterogeneity. Here, we report a genome screen of nine BSCL families from two geographical clusters (in Lebanon and Norway). We identified a new disease locus, designated BSCL2, within the 2.5-Mb interval flanked by markers D11S4076 and D11S480 on chromosome 11q13. Analysis of 20 additional families of various ethnic origins led to the identification of 11 families in which the disease cosegregates with the 11q13 locus; the remaining families provide confirmation of linkage to 9q34. Sequence analysis of genes located in the 11q13 interval disclosed mutations in a gene homologous to the murine guanine nucleotide-binding protein (G protein), gamma3-linked gene (Gng3lg) in all BSCL2-linked families. BSCL2 is most highly expressed in brain and testis and encodes a protein (which we have called seipin) of unknown function. Most of the variants are null mutations and probably result in a severe disruption of the protein. These findings are of general importance for understanding the molecular mechanisms underlying regulation of body fat distribution and insulin resistance.     

Efficacy of some histochemical techniques for acid mucopolysaccharides

Résumé L'efficacité relative de certaines méthodes histochimiques utilisées habituellement pour la mise en évidence des mucopolysaccharides acides a été étudiée sur des peaux de rats soumises à des conditions expérimentales diverses. Les différentes concentrations des substances en étude étaient connues, ayant été quantitativement déterminées par la méthode chimique dePearce etWatson. La réaction métachromatique, réalisée avec les précautions nécessaires et avec le concours de la digestion par l'hyaluronidase, nous a fourni une image fidèle de la concentration de mucopolysaccharides acides. Ce n'est pas le cas lorsqu'on emploie l'acide périodique-Schiff ou le fer colloïdal qui ne semblent pas être très utiles pour la mise en évidence des substances étudiées.