Effects of MDMA Injections on the Behavior of Socially-Housed Long-Tailed Macaques (Macaca fascicularis)

3,4-methylenedioxy-N-methyl amphetamine (MDMA) is one of the few known molecules to increase human and rodent prosocial behaviors. However, this effect has never been assessed on the social behavior of non-human primates. In our study, we subcutaneously injected three different doses of MDMA (1.0, 1.5 or 2.0mg/kg) to a group of three, socially housed, young male long-tailed macaques. More than 200 hours of behavioral data were recorded, during 68 behavioral sessions, by an automatic color-based video device that tracked the 3D positions of each animal and of a toy. This data was then categorized into 5 exclusive behaviors (resting, locomotion, foraging, social contact and object play). In addition, received and given social grooming was manually scored. Results show several significant dose-dependent behavioral effects. At 1.5mg/kg only, MDMA induces a significant increase in social grooming behavior, thus confirming the prosocial effect of MDMA in macaques. Additionally, at 1.5 and 2.0 mg/kg MDMA injection substantially decreases foraging behavior, which is consistent with the known anorexigenic effect of this compound. Furthermore, at 2.0 mg/kg MDMA injection induces an increase in locomotor behavior, which is also in accordance with its known stimulant property. Interestingly, MDMA injected at 1.0mg/kg increases the rate of object play, which might be interpreted as a decrease of the inhibition to manipulate a unique object in presence of others, or, as an increase of the intrinsic motivation to manipulate this object. Together, our results support the effectiveness of MDMA to study the complex neurobiology of primates’ social behaviors.     

Green microalgae in intermittent light: a meta-analysis assisted by machine learning

Journal of Applied Phycology - Microalgal biotechnology still needs to alleviate the productivity bottleneck before achieving the full extent of its promises. With this goal in mind, many studies...     

Clonal Characterization of Rat Muscle Satellite Cells: Proliferation,Metabolism and Differentiation Define an Intrinsic Heterogeneity

Satellite cells (SCs) represent a distinct lineage of myogenic progenitors responsible for the postnatal growth, repair and maintenance of skeletal muscle. Distinguished on the basis of their unique position in mature skeletal muscle, SCs were considered unipotent stem cells with the ability of generating a unique specialized phenotype. Subsequently, it was demonstrated in mice that opposite differentiation towards osteogenic and adipogenic pathways was also possible. Even though the pool of SCs is accepted as the major, and possibly the only, source of myonuclei in postnatal muscle, it is likely that SCs are not all multipotent stem cells and evidences for diversities within the myogenic compartment have been described both in vitro and in vivo. Here, by isolating single fibers from rat flexor digitorum brevis (FDB) muscle we were able to identify and clonally characterize two main subpopulations of SCs: the low proliferative clones (LPC) present in major proportion (∼75%) and the high proliferative clones (HPC), present instead in minor amount (∼25%). LPC spontaneously generate myotubes whilst HPC differentiate into adipocytes even though they may skip the adipogenic program if co-cultured with LPC. LPC and HPC differ also for mitochondrial membrane potential (ΔΨ_m), ATP balance and Reactive Oxygen Species (ROS) generation underlying diversities in metabolism that precede differentiation. Notably, SCs heterogeneity is retained in vivo. SCs may therefore be comprised of two distinct, though not irreversibly committed, populations of cells distinguishable for prominent differences in basal biological features such as proliferation, metabolism and differentiation. By these means, novel insights on SCs heterogeneity are provided and evidences for biological readouts potentially relevant for diagnostic purposes described.     

Estrogen receptor-alpha, bcl-2 and c-myc gene expression in fibroadenomas and adjacent normal breast: association with nodule size, hormonal and reproductive features

Fibroadenomas are the most common benign lump in females. The study of gene alterations and/or deregulation in reproductive years may help explain hormonal physiological processes involved in nodule development and evolution. The objective was to compare ER-alpha, c-myc, and bcl-2 gene expression in breast fibroadenomas and in normal tissue and evaluate menstrual cycle, parity, and oral contraceptive influences. Fifty-seven premenopausal women (14-49 years) undergoing surgical removal of fibroadenomas were selected. Samples from fibroadenomas and circumjacent normal tissue were obtained for RT-PCR paired analysis. Patients were divided in groups according to menstrual cycle, use of contraceptives and parity. Tissue from 32 patients was adequate for RT-PCR. Paired analysis showed higher expression of ER-alpha (P=0.012) and bcl-2 (P=0.001) in fibroadenomas than in normal breast, while c-myc presented a similar expression (P=0.655). ER-alpha was higher in fibroadenomas of patients in follicular phase versus contraceptive users and normal tissue (P=0.003); bcl-2 was higher in fibroadenomas of patients in luteal phase than in the normal samples from all groups (P=0.007). c-myc did not differ according to menstrual cycle, but was higher in fibroadenomas>3 cm versus<3 cm (P=0.015) and in nulliparous women (P=0.04). A positive correlation between c-myc levels and fibroadenoma diameter was demonstrated (r=0.536; P=0.007). Nulliparous mean nodule diameter was superior than parous women (P=0.008). In conclusion, the expression of ER-alpha, bcl-2 and c-myc depends on hormonal and reproductive factors, with a possible contribution to lump formation and evolution.     

Design of a stirred multiwell bioreactor for expansion of CD34+ umbilical cord blood cells in hypoxic conditions

Besides having a metabolic role, oxygen is recognized as an important signaling stimulus for stem cells. In hematopoiesis, hypoxia seems to favor stem cell self‐renewal. In fact, long‐term repopulating hematopoietic stem cells reside in bone marrow at concentrations as low as 1% oxygen. However, O₂ concentration is difficult to control in vitro. Thermodynamically, we found significant differences between O₂ solubility in different media, and in presence of serum. Furthermore, we verified that medium equilibration with a hypoxic atmosphere requires several hours. Thus, in a static culture, the effective O₂ concentration in the cell immediate microenvironment is difficult to control and subject to concentration gradients. Stirred systems improve homogeneity within the culture volume. In this work, we developed a stirred bioreactor to investigate hypoxia effect on the expression of stem cell markers in CD34⁺ cells from umbilical cord blood. The stirring system was designed on top of a standard six‐well plate to favor continuity with conventional static conditions and transfer of culture protocols. The bioreactor volume (10 mL/well) is suitable for cell expansion and multiparametric flow cytometry analyses. First, it was tested at 21% O₂ for biocompatibility and other possible effects on the cells compared to static conditions. Then, it was used to study c‐kit expression of CD34⁺ cells at 5% O₂, using 21%‐O₂ cultures as a control. In hypoxia we found that CD34⁺ cells maintained a higher expression of c‐kit. Further investigation is needed to explore the dynamics of interaction between oxygen‐ and c‐kit‐dependent pathways at the molecular level. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011     

An improved procedure for the synthesis of branched polyethylene glycols (PEGs) with the reporter dipeptide Met-betaAla for protein conjugation.

A new and more efficient route to the synthesis of branched PEG for protein conjugation, bearing a reporter dipeptide Met-betaAla, is described, which allows better purification of the final product by ion exchange chromatography. The product has the combined advantages of an 'umbrella-like' branched structure, which allows a better coverage of the protein surface, and the presence of the dipeptide Met-betaAla which has been used to detect the position of PEGylation within the peptide sequence.     

Compete to Play: Trade-Off with Social Contact in Long-Tailed Macaques (Macaca fascicularis)

Many animal species engage in various forms of solitary object play, but this activity seems to be of particular importance in primates. If playing objects constitute a valuable resource, and access to such objects is limited, a competitive context may arise. We inserted a unique toy within a mini-colony of long-tailed macaque (Macaca fascicularis) and compared their behaviors to sessions without playing object. An automatic color-based 3D video device was used to track the positions of each animal and the toy, and this data was categorized into 5 exclusive behaviors (resting, locomotion, foraging, social contact and object play). As expected, the delay to first access to the object reflected the hierarchy of the colony, indicating that a competition took place to own this unique resource of entertainment. In addition, we found that the amount of object play was not correlated with social or foraging behavior, suggesting independent motivational mechanisms. Conversely, object playing time was negatively correlated with idling time, thus indicating its relation to pastime activities. Interestingly, the amount of social contacts in the group was significantly reduced by the heightened competitive context, suggesting that competitors are more likely to be perceived as potential threat requiring caution, as shown in humans. Experimental manipulation of competitive contexts in primates reveals common mental processes involved in social judgment, and shows that access to valuable resources can be a sufficient cause for variations in group cohesion.     

Stem cells from fetal membranes and amniotic fluid: markers for cell isolation and therapy

Stem cell therapy is in constant need of new cell sources to conceive regenerative medicine approaches for diseases that are still without therapy. Scientists drew the attention toward amniotic membrane and amniotic fluid stem cells, since these sources possess many advantages: first of all as cells can be extracted from discarded foetal material it is inexpensive, secondly abundant stem cells can be obtained and finally, these stem cell sources are free from ethical considerations. Many studies have demonstrated the differentiation potential in vitro and in vivo toward mesenchymal and non-mesenchymal cell types; in addition the immune-modulatory properties make these cells a good candidate for allo- and xenotransplantation. This review offers an overview on markers characterisation and on the latest findings in pre-clinical or clinical setting of the stem cell populations isolated from these sources.     

Spi2 gene polymorphism is not associated with recurrent airway obstruction and inflammatory airway disease in thoroughbred horses

The aim was to detect the presence of polymorphisms at exons 1, 2, 3 and 4 of the Spi2 gene, and evaluate a possible association between them and recurrent airway obstruction (RAO) or inflammatory airway disease (IAD) in thoroughbred horses, through single-strand conformational-polymorphism (SSCP) screening. Although polymorphism was not detected in exons 1, 2 and 3, three alleles and six genotypes were identified in exon 4. The frequencies of allele A (0.6388) and genotype AA (0.3888) were higher in horses affected by RAO, although no association was found between polymorphism and horses with either RAO or IAD.