Hematological,biochemical, respiratory,cardiovascular and electroneurophysiological parameters in African green monkeys (Cercopithecus aethiops sabaeus). Its use in non‐clinical toxicological studies

Background The purpose of this study is to better characterize the hematological, biochemical, respiratory, cardiovascular and electroneurophysiological parameters in young adult Cercopithecus aethiops sabaeus of both sexes. The rhesus and cynomolgus monkeys are widely used as experimental primate models. However, only few articles have been published testing toxicological effects of pharmaceuticals on African green monkey. Methods The present study was carried out with the recompilation of all parameters recorded before the first drug administration in five sub‐chronic or chronic toxicological studies performed on 66 Cercopithecus aethiops sabaeus, born in Cuba. Results This study provides hematological, biochemical, respiratory, cardiovascular and electroneurophysiological data for both choosing animals to be included into experiments and monitoring these parameters during the study. Conclusions We conclude that this study provides valuable integrated data for determining the health status, including electroneurophysiological parameters, data not previously reported for this species, of the African green monkey.     

New PCR ribotypes of Clostridium difficile detected in children in Brazil

A total of 35 Brazilian isolates of Clostridium difficile from faecal stools and four isolates from hospital environments were analyzed by PCR ribotyping. A whole cell protein profile (as an alternative for serogrouping), in vitro toxin production and susceptibility to vancomycin, metronidazole and clindamycin were also investigated. All strains were typeable by both phenotypic and genotypic methods, and a total of 13 different PCR ribotypes were identified, of which seven (132, 133, 134, 135, 136, 142 and 143) were considered new types and accounted for 78.5% of all samples evaluated (including hospital environments). A non-toxigenic C. difficile PCR ribotype 133 was detected in all children groups examined (inpatients, outpatients and healthy children), whilst toxigenic PCR ribotypes 015, 131, 134 and 135 were associated mostly with symptomatic children. Serogroups G and D were disseminated both in patients from the community and from the pediatric hospital, with group G prevalent among outpatient children. All strains were susceptible to vancomycin and metronidazole but high levels of resistance to clindamycin were found, especially among serogroups G and D. Co-existence of different ribotypes and serogroups in the same individual was observed. The new seven ribotypes found in this investigation may represent strains characteristic of this region of Brazil.     

Some propagation methods for cloning holm oak (<Emphasis Type="Italic">Quercus ilex</Emphasis> L.) plants

Holm oak (Quercus ilex L.), a typical evergreen tree of the Mediterranean area, is very important due to its ecological and economical values. Propagation of this species is extremely difficult and traditionally carried out only by seed germination. In this work, mature acorns were germinated in vitro and in peat substrate in aseptic and non-aseptic conditions. Explants from the seedlings obtained were propagated in vitro in WPM plus 4 μM BA. Plant regeneration was achieved from hypocotyls and root segments cultured in vitro on modified Gamborg medium plus 20 μM BA and 20 μM NAA. 13.8% of the hypocotyls and approximately 30% of the root segments developed both shoots and roots after 30 days of culture. Rooting of stem segments was obtained both in vitro and ex vitro by basal dipping in IBA solutions. Within ex vitro rooting, mother plant age had major influence on the percentage of rooting of the cuttings as the younger plants showed higher ability to root. In this way, Q. ilex plants could be propagated and cloned. The procedure described here would be a very useful tool for breeding programs since vegetative propagation of selected individuals can be achieved.     

In vitro assembly properties of mutant and chimeric intermediate filament proteins: insight into the function of sequences in the rod and end domains of IF

The factors and mechanisms regulating assembly of intermediate filament (IF) proteins to produce filaments with their characteristic 10 nm diameter are not fully understood. All IF proteins contain a central rod domain flanked by variable head and tail domains. To elucidate the role that different domains of IF proteins play in filament assembly, we used negative staining and electron microscopy (EM) to study the in vitro assembly properties of purified bacterially expressed IF proteins, in which specific domains of the proteins were either mutated or swapped between a cytoplasmic (mouse neurofilament-light (NF-L) subunit) and nuclear intermediate filament protein (human lamin A). Our results indicate that filament formation is profoundly influenced by the composition of the assembly buffer. Wild type (wt) mouse NF-L formed 10 nm filaments in assembly buffer containing 175 mM NaCl, whereas a mutant deleted of 18 NH2-terminal amino acids failed to assemble under similar conditions. Instead, the mutant assembled efficiently in buffers containing CaCl2 > or = 6 mM forming filaments that were 10 times longer than those formed by wt NF-L, although their diameter was significantly smaller (6-7 nm). These results suggest that the 18 NH2-terminal sequence of NF-L might serve two functions, to inhibit filament elongation and to promote lateral association of NF-L subunits. We also demonstrate that lengthening of the NF-L rod domain, by inserting a 42 aa sequence unique to nuclear IF proteins, does not compromise filament assembly in any noticeable way. Our results suggests that the known inability of nuclear lamin proteins to assemble into 10 nm filaments in vitro cannot derive solely from their longer rod domain. Finally, we demonstrate that the head domain of lamin A can substitute for that of NF-L in filament assembly, whereas substitution of both the head and tail domains of lamins for those of NF-L compromises assembly. Therefore, the effect of lamin A "tail" domain alone, or the synergistic effect of lamin "head" and the "tail" domains together, interferes with assembly into 10-nm filaments.     

Papillomavirus-like particles are an effective platform for amyloid-beta immunization in rabbits and transgenic mice

Immunization with amyloid-beta (Abeta) prevents the deposition of Abeta in the brain and memory deficits in transgenic mouse models of Alzheimer's disease (AD), opening the possibility for immunotherapy of AD in humans. Unfortunately, the first human trial of Abeta vaccination was complicated, in a small number of vaccinees, by cell-mediated meningoencephalitis. To develop an Abeta vaccine that lacks the potential to induce autoimmune encephalitis, we have generated papillomavirus-like particles (VLP) that display 1-9 aa of Abeta protein repetitively on the viral capsid surface (Abeta-VLP). This Abeta peptide was chosen because it contains a functional B cell epitope, but lacks known T cell epitopes. Rabbit and mouse vaccinations with Abeta-VLP were well tolerated and induced high-titer autoAb against Abeta, that inhibited effectively assembly of Abeta(1-42) peptides into neurotoxic fibrils in vitro. Following Abeta-VLP immunizations of APP/presenilin 1 transgenic mice, a model for human AD, we observed trends for reduced Abeta deposits in the brain and increased numbers of activated microglia. Furthermore, Abeta-VLP vaccinated mice also showed increased levels of Abeta in plasma, suggesting efflux from the brain into the vascular compartment. These results indicate that the Abeta-VLP vaccine induces an effective humoral immune response to Abeta and may thus form a basis to develop a safe and efficient immunotherapy for human AD.     

Hyperosmotic stress-dependent NFkappaB activation is regulated by reactive oxygen species and IGF-1 in cultured cardiomyocytes

We have recently shown that hyperosmotic stress activates p65/RelB NFkappaB in cultured cardiomyocytes with dichotomic actions on caspase activation and cell death. It remains unexplored how NFkappaB is regulated in cultured rat cardiomyocytes exposed to hyperosmotic stress. We study here: (a) if hyperosmotic stress triggers reactive oxygen species (ROS) generation and in turn whether they regulate NFkappaB and (b) if insulin-like growth factor-1 (IGF-1) modulates ROS production and NFkappaB activation in hyperosmotically-stressed cardiomyocytes. The results showed that hyperosmotic stress generated ROS in cultured cardiac myocytes, in particular the hydroxyl and superoxide species, which were inhibited by N-acetylcysteine (NAC). Hyperosmotic stress-induced NFkappaB activation as determined by IkappaBalpha degradation and NFkappaB DNA binding. NFkappaB activation and procaspase-3 and -9 fragmentation were prevented by NAC and IGF-1. However, this growth factor did not decrease ROS generation induced by hyperosmotic stress, suggesting that its actions over NFkappaB and caspase activation may be due to modulation of events downstream of ROS generation. We conclude that hyperosmotic stress induces ROS, which in turn activates NFkappaB and caspases. IGF-1 prevents NFkappaB activation by a ROS-independent mechanism.     

Association of fragile site-associated (FSA) gene expression with epithelial differentiation and tumor development

A novel gene designated as fragile site-associated (FSA) gene was recently identified by positional cloning from the CHO 1q31 fragile site which plays an important role in regulating amplification of multidrug resistance (mdr1) gene in multidrug-resistant cells. FSA produces a message of approximately 16 kb which encodes an open-reading frame of 5005 amino acids. FSA shares sequence similarity with that in Caenorhabditis elegans lpd-3, a lipid storage gene. Using immunohistochemical staining and RNA in situ hybridization we report here that expression of FSA is associated with developmental programs of spermatogenesis and mammary gland in mice. Real-time RT-PCR results also support the upregulation of FSA expression in mammary gland development. Expression of FSA in many tissues including colon, skin, ovary, prostate, and bladder is mainly in the postmitotic, well-differentiated compartments. Moreover, levels of FSA expression are downregulated in tumors of these tissue origins. These results suggest that FSA also plays important roles in regulating mammalian epithelial growth and differentiation and tumor development.     

Myocardial Chemokine Expression and Intensity of Myocarditis in Chagas Cardiomyopathy Are Controlled by Polymorphisms in CXCL9 and CXCL10

Background

Chronic Chagas cardiomyopathy (CCC), a life-threatening inflammatory dilated cardiomyopathy, affects 30% of the approximately 8 million patients infected by Trypanosoma cruzi. Even though the Th1 T cell-rich myocarditis plays a pivotal role in CCC pathogenesis, little is known about the factors controlling inflammatory cell migration to CCC myocardium.

Methods and Results

Using confocal immunofluorescence and quantitative PCR, we studied cell surface staining and gene expression of the CXCR3, CCR4, CCR5, CCR7, CCR8 receptors and their chemokine ligands in myocardial samples from end-stage CCC patients. CCR5+, CXCR3+, CCR4+, CCL5+ and CXCL9+ mononuclear cells were observed in CCC myocardium. mRNA expression of the chemokines CCL5, CXCL9, CXCL10, CCL17, CCL19 and their receptors was upregulated in CCC myocardium. CXCL9 mRNA expression directly correlated with the intensity of myocarditis, as well as with mRNA expression of CXCR3, CCR4, CCR5, CCR7, CCR8 and their ligands. We also analyzed single-nucleotide polymorphisms for genes encoding the most highly expressed chemokines and receptors in a cohort of Chagas disease patients. CCC patients with ventricular dysfunction displayed reduced genotypic frequencies of CXCL9 rs10336 CC, CXCL10 rs3921 GG, and increased CCR5 rs1799988CC as compared to those without dysfunction. Significantly, myocardial samples from CCC patients carrying the CXCL9/CXCL10 genotypes associated to a lower risk displayed a 2–6 fold reduction in mRNA expression of CXCL9, CXCL10, and other chemokines and receptors, along with reduced intensity of myocarditis, as compared to those with other CXCL9/CXCL10 genotypes.

Conclusions

Results may indicate that genotypes associated to reduced risk in closely linked CXCL9 and CXCL10 genes may modulate local expression of the chemokines themselves, and simultaneously affect myocardial expression of other key chemokines as well as intensity of myocarditis. Taken together our results may suggest that CXCL9 and CXCL10 are master regulators of myocardial inflammatory cell migration, perhaps affecting clinical progression to the life-threatening form of CCC.     

Catalysts of Cu(II) and Co(II) ions adsorbed in chitosan used in transesterification of soy bean and babassu oils - a new route for biodiesel syntheses

Catalysts of Cu(II) and Co(II) adsorbed in chitosan was used in transesterification of soy bean and babassu oils. The catalysts were characterized by infrared, atomic absorption and TG, and biodiesels was characterized by infrared, NMR, CG, TG, physic chemistry analysis. The maximum adsorption values found for copper and cobalt cations were 1.584 and 1.260mgg(-1), respectively, in 180min. However, conversion of oils in biodiesel was better when used Co(II) adsorbed in chitosan.     

Influence of carbon source and concentration on the in vitro development of olive zygotic embryos and explants raised from them

The influence of sucrose or mannitol on in vitro zygotic embryo germination, seedling development and explant propagation of olive tree (Olea europaea L.) was compared. Embryos germinated without sucrose in the medium but for adequate development of the seedlings to yield viable plants, a carbohydrate supply was necessary; both sucrose and mannitol were equally suitable for this purpose. However, when explants obtained from in vitro germinated embryos were cultured with mannitol or sucrose, then the polyalcohol promoted significantly more growth than sucrose by increasing shoot length, pairs of leaves formed, and breaking apical dominance. This improved the in vitro culture of olive plant material, thus allowing new olive clonal lines to be obtained in shorter times. This will assist in future breeding experiments with the species.