Population and Single-Cell Analysis of Human Cardiogenesis Reveals Unique LGR5 Ventricular Progenitors in Embryonic Outflow Tract

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Rapid method to obtain high quality nuclear and chromosome images directly from living cells in the Characeae

This study focused on a method based on the capacity of cationic dyes to stain only the nucleus and chromosomes in cells subjected to either acid or alkaline hydrolysis. The method and the squash were optimized for the Characeae and were described in detail. Nuclei from vegetative shoot apices and antheridial filament cells of unfixed, fixed and herbarium material of Nitella opaca were investigated using the Azure A or Toulidine Blue stains. Comparisons with some other staining methods, used in the previous studies, were also reported. The Azure A/Toulidine Blue method is useful to obtain clear images of chromosome morphology comparable or higher to that obtained with Feulgen or Aceto‐Orcein. It requires little time and a less complicated procedure in comparison with other staining methods.     

Proteome analysis of whole saliva: a new tool for rheumatic diseases--the example of Sjögren's syndrome

Sj?gren's syndrome (pSS) is a systemic disease that affects salivary glands directly, and is therefore expected to influence the composition of human whole saliva (WS) fluid. The aim of this study was to characterize the WS proteins of pSS patients using a proteomic approach to assess a valid procedure to examine the global changes of the salivary protein profiles in connective tissue disorders. The WS proteins expressed in patients affected by pSS and healthy volunteers were analyzed using the 2-DE technique. The WS protein pattern was altered in pSS patients compared to controls, with a decrease in some of the typical salivary proteins. Particularly, a remarkable alteration of carbonic anhydrase VI was observed. Moreover, a comparison of WS protein profile of pSS patients with the one obtained from controls revealed a set of differentially expressed proteins. These proteins were related to acute and chronic inflammation while some others were involved in oxidative stress injury. These findings are in line with the systemic immuno-inflammatory aspects of pSS and open the possibility for a systematic search of diagnostic biomarkers and targets for therapeutic intervention in pSS.     

AMPA receptor expression in mouse testis and spermatogonial GC-1 cells: A study on its regulation by excitatory amino acids

Excitatory amino acids (EAAs) are found present in the nervous and reproductive systems of animals. Numerous studies have demonstrated a regulatory role for Glutamate (Glu), d -aspartate ( d -Asp) and N-methyl- d -aspartate (NMDA) in the control of spermatogenesis. EAAs are able to stimulate the Glutamate receptors, including the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR). Here in, we assess expression of the main AMPAR subunits, GluA1 and GluA2/3, in the mouse testis and in spermatogonial GC-1 cells. The results showed that both GluA1 and GluA2/3 were localized in mouse testis prevalently in spermatogonia. The subunit GluA2/3 was more highly expressed compared with GluA1 in both the testis and the GC-1 cells. Subsequently, GC-1 cells were incubated with medium containing l -Glu, d -Glu, d -Asp or NMDA to determine GluA1 and GluA2/3 expressions. At 30 minutes and 2 hours of incubation, EAA-treated GC-1 cells showed significantly higher expression levels of both GluA1 and GluA2/3. Furthermore, p-extracellular signal-regulated kinase (ERK), p-Akt, proliferating cell nuclear antigen (PCNA), and Aurora B expressions were assayed in l -Glu-, d -Glu-, and NMDA-treated GC-1 cells. At 30 minutes and 2 hours of incubation, treated GC-1 cells showed significantly higher expression levels of p-ERK and p-Akt. A consequent increase of PCNA and Aurora B expressions was induced by l -Glu and NMDA, but not by d -Glu. Our study demonstrates a direct effect of the EAAs on spermatogonial activity. In addition, the increased protein expression levels of GluA1 and GluA2/3 in EAA-treated GC-1 cells suggest that EAAs could activate ERK and Akt pathways through the AMPAR. Finally, the increased PCNA and Aurora B levels may imply an enhanced proliferative activity.     

Proteomics for the detection of indirect markers of steroids treatment in bovine muscle

Despite the ban by the European Union, anabolic steroids might still be illicitly employed in bovine meat production. The surveillance of misuse of such potentially harmful molecules is necessary to guarantee consumers’ health. Analytical methods for drug residue control are based on LC‐MS/MS, but their efficacy can be hindered due to undetectable residual concentrations as a result of low‐dosage treatments. Screening methods based on the recognition of indirect biological effects of growth promoters’ administration, such as the alteration of protein expression, can improve the efficacy of surveillance. The present study was aimed at identifying modifications in the muscle protein expression pattern between bulls treated with an ear implant (Revalor‐XS®) containing trenbolone acetate (200 mg) and estradiol (40 mg), and untreated animals. The analysis of skeletal muscle was carried out using a tandem mass tags shotgun proteomics approach. We defined 28 candidate protein markers with a significantly altered expression induced by steroids administration. A subset of 18 candidate markers was validated by SRM and allowed to build a predictive model based on partial least square discriminant analysis. Our findings confirm the effectiveness of the proteomics approach as potential tool to overcome analytical limitations of drug residue monitoring.     

Comparative cytogenetics in four species of Palinuridae: B chromosomes, ribosomal genes and telomeric sequences

The evolutionary pathway of Palinuridae (Crustacea, Decapoda) is still controversial, uncertain and unexplored, expecially from a karyological point of view. Here we describe the South African spiny lobster Jasus lalandii karyotype: n and 2n values, heterochromatin distribution, nucleolar organizer region (NOR) location and telomeric repeat structure and location. To compare the genomic and chromosomal organization in Palinuridae we located NORs in Panulirus regius, Palinurus gilchristi and Palinurus mauritanicus: all species showed multiple NORs. In J. lalandii NORs were located on three chromosome pairs, with interindividual polymorphism. In P. regius and in the two Palinurus species NORs were located on two chromosome pairs. In the two last species 45S ribosomal gene loci were also found on B chromosomes. In addition, the nature and location of telomeric repeats were investigated by FISH in J. lalandii, P. gilchristi, P. mauritanicus Palinurus elephas, and P. regius (Palinuridae, Achelata), and in Scyllarus arctus (Scyllaridae, Achelata): all these Achelata species showed the (TTAGG)n pentameric repeats. Furthermore, in J. lalandii these repeats occurred in all the telomeres and in some interstitial chromosomal sites, associated with NORs.