Managing Plant Resources: How Intensive Can it be?

Previous studies have shown there is a wide spectrum of incipient management practices between gathering and agriculture, that include resources commonly considered “wild.” Based on the study of 20 species used as foodstuffs in the community of Santa María Tecomavaca (Mexico), we evaluated nonagricultural management forms such as gathering, incipient nonselective management, incipient selective management and occasional ex situ cultivation to learn if they represent a gradient in the intensity of manipulation of a resource. The way in which the intensity of manipulation of a resource can vary as a function of cultural importance and the species’ biology was also analyzed. Using an index that measures the intensity of management of a resource, it has been established that the degree of intensity depends on: the specialization of the practices directed to the environment as well as to the individuals; the number of persons performing these practices; and the number of different practices taking place. The degree of management intensity is also a consequence of the joint action of cultural importance and of species’ biology.

A novel method to screen genomic libraries that combines genomic immunization with the prime-boost strategy

We employed a prime-boost regimen in combination with the expression library immunization protocol to improve the protective effectiveness of a genomic library used as immunogen. To demonstrate the feasibility of this novel strategy, we used as a prime a serogroup B Neisseria meningitidis random genomic library constructed in a eukaryotic expression vector. Mice immunized with different fractions of this library and boosted with a single dose of meningococcal outer membrane vesicles elicited higher bactericidal antibody titers compared with mice primed with the empty vector. After the boost, passive administration of sera from mice primed with two of these fractions significantly reduced the number of viable bacteria in the blood of infant rats challenged with live N. meningitidis. The method proposed could be applied to the identification of subimmunogenic antigens during vaccine candidate screening by employing expression library immunization.     

Genetic analysis of the endemic island loggerhead shrike, <Emphasis Type="Italic">Lanius ludovicianus anthonyi</Emphasis>

Based on limited research, the island loggerhead shrike, Lanius ludovicianus anthonyi has been considered a distinct subspecies endemic to the northern California Channel Islands. We used mtDNA control region sequences and microsatellite genotyping to compare loggerhead shrikes from the southern California mainland (L. l. gambeli), San Clemente Island (L. l. mearnsi), and the northern islands (L. l. anthonyi). Habitats on the islands are recovering due to the removal of non-native ungulates on the islands, but may be transitioning to habitats less supportive of loggerhead shrikes, so this evaluation comes at a critical time. We utilized 96 museum specimens that were collected over a century to evaluate both spatial and temporal genetic patterns. Analysis of multilocus microsatellite genotypes indicated that historical specimens of loggerhead shrikes (collected between 1897 and 1986) from the two northern islands of Santa Rosa and Santa Cruz are genetically distinct from adjacent mainland and island shrikes. Birds from Santa Catalina Island showed mixed ancestry and did not cluster with the northern island birds. Historical specimens of L. l. mearnsi from San Clemente Island also showed mixed ancestry. Our study provides evidence that a genetically distinct form of loggerhead shrikes, L. l. anthonyi, occurred on the islands of Santa Rosa and Santa Cruz.     

Ani s 10, a new Anisakis simplex allergen: cloning and heterologous expression

Anisakiasis is a human disease caused by accidental ingestion of larval nematodes belonging to the Anisakidae family. Anisakiasis is often associated with a strong allergic response. Diagnosis of A. simplex allergy is currently carried out by test based on the IgE reactivity to a complete extract of L3 Anisakis larvae although the specificity of these diagnostic tests is poor. Improving the specificity of the diagnostic test is possible using purified recombinant allergens. A new Anisakis allergen, named Ani s 10, was detected by immunoscreening an expression cDNA library constructed from L3 Anisakis simplex larvae. The new allergen was overproduced in Escherichia coli; it is a protein of 212 amino acids and it was localized as a 22 kDa protein band in an ethanol fractionated extract from the parasite. Ani s 10 has no homology with any other described protein, and its sequence is composed by seven almost identical repetitions of 29 amino acids each. A total of 30 of 77 Anisakis allergic patients (39%) were positive both to rAni s 10 and natural Ani s 10 by immunoblotting. The new allergen could be useful in a component-resolved diagnosis system for Anisakis allergy.     

Targeting MAGE-C1/CT7 expression increases cell sensitivity to the proteasome inhibitor bortezomib in multiple myeloma cell lines

The MAGE-C1/CT7 encodes a cancer/testis antigen (CTA), is located on the chromosomal region Xq26-27 and is highly polymorphic in humans. MAGE-C1/CT7 is frequently expressed in multiple myeloma (MM) that may be a potential target for immunotherapy in this still incurable disease. MAGEC1/CT7 expression is restricted to malignant plasma cells and it has been suggested that MAGE-C1/CT7 might play a pathogenic role in MM; however, the exact function this protein in the pathophysiology of MM is not yet understood. Our objectives were (1) to clarify the role of MAGE-C1/CT7 in the control of cellular proliferation and cell cycle in myeloma and (2) to evaluate the impact of silencing MAGE-C1/CT7 on myeloma cells treated with bortezomib. Myeloma cell line SKO-007 was transduced for stable expression of shRNA-MAGE-C1/CT7. Downregulation of MAGE-C1/CT7 was confirmed by real time quantitative PCR and western blot. Functional assays included cell proliferation, cell invasion, cell cycle analysis and apoptosis. Western blot showed a 70-80% decrease in MAGE-C1/CT7 protein expression in inhibited cells (shRNA-MAGE-C1/CT7) when compared with controls. Functional assays did not indicate a difference in cell proliferation and DNA synthesis when inhibited cells were compared with controls. However, we found a decreased percentage of cells in the G2/M phase of the cell cycle among inhibited cells, but not in the controls (p<0.05). When myeloma cells were treated with bortezomib, we observed a 48% reduction of cells in the G2/M phase among inhibited cells while controls showed 13% (empty vector) and 9% (ineffective shRNA) reduction, respectively (p<0.01). Furthermore, inhibited cells treated with bortezomib showed an increased percentage of apoptotic cells (Annexin V+/PI-) in comparison with bortezomib-treated controls (p<0.001). We found that MAGE-C1/CT7 protects SKO-007 cells against bortezomib-induced apoptosis. Therefore, we could speculate that MAGE-C1/CT7 gene therapy could be a strategy for future therapies in MM, in particular in combination with proteasome inhibitors.     

Placenta growth factor-1 exerts time-dependent stabilization of adherens junctions following VEGF-induced vascular permeability

Increased vascular permeability is an early event characteristic of tissue ischemia and angiogenesis. Although VEGF family members are potent promoters of endothelial permeability the role of placental growth factor (PlGF) is hotly debated. Here we investigated PlGF isoforms 1 and 2 and present in vitro and in vivo evidence that PlGF-1, but not PlGF-2, can inhibit VEGF-induced permeability but only during a critical window post-VEGF exposure. PlGF-1 promotes VE-cadherin expression via the trans-activating Sp1 and Sp3 interaction with the VE-cadherin promoter and subsequently stabilizes transendothelial junctions, but only after activation of endothelial cells by VEGF. PlGF-1 regulates vascular permeability associated with the rapid localization of VE-cadherin to the plasma membrane and dephosphorylation of tyrosine residues that precedes changes observed in claudin 5 tyrosine phosphorylation and membrane localization. The critical window during which PlGF-1 exerts its effect on VEGF-induced permeability highlights the importance of the translational significance of this work in that PLGF-1 likely serves as an endogenous anti-permeability factor whose effectiveness is limited to a precise time point following vascular injury. Clinical approaches that would pattern nature's approach would thus limit treatments to precise intervals following injury and bring attention to use of agents only during therapeutic windows.     

Influence of storage time on functional capacity of flow cytometrically sex-sorted boar spermatozoa

Sex-sorting of boar spermatozoa is an emerging biotechnology, still considered suboptimal owing to the slowness of the process, which requires long sorting periods to obtain an adequate number of spermatozoa to perform a non-surgical insemination. This period involves storage of sorted cells that could impair their functional capacity. Here, we have studied how the storage of sex-sorted boar spermatozoa affects their functional capacity. Sorted spermatozoa were assessed at various times (0, 2, 5h or 10h) during storage after sorting and compared with diluted and unsorted spermatozoa for sperm motility patterns, plasma membrane and acrosomal integrity and their ability to penetrate homologous IVM oocytes. Sex-sorted sperm motility and membrane integrity only decreased significantly (p<0.05) by the end of the storage period (10h) compared to unsorted spermatozoa. Sperm velocity, ALH and Dance increased significantly (p<0.05), immediately post-sorting, returning to unsorted sperm values during storage. Acrosome integrity was not seriously affected by the sorting process, but decreased (p<0.05) during storage after sorting. Sorted spermatozoa stored 2h after sorting did not differ from unsorted in penetration rates and numbers of spermatozoa per oocyte, reaching the highest (p<0.05) penetration rates and sperm numbers per oocyte, when co-cultured for 6 or more hours. Non-storage or storage for 5h or 10h negatively (p<0.05) affected sperm penetration ability. In conclusion, although flow cytometrically sex-sorted spermatozoa are able to maintain motility, viability and acrosomal integrity at optimal levels until 10h of storage after sorting, fertilizing ability is maintained only over shorter storage times (<5h).     

Genetic differentiation and estimation of effective population size and migration rates in two sympatric ecotypes of the marine snail Littorina saxatilis

On exposed rocky shores in Galicia (northwest Spain), a striking polymorphism exists between two ecotypes (RB and SU) of Littorina saxatilis that occupy different levels of the intertidal zone and exhibit an incomplete reproductive isolation. The setting has been suggested to represent ongoing sympatric speciation by ecological adaptation of the two ecotypes to their respective habitats. In this article we address whether or not the ecotypes have developed their own population structures in response to the rigors of their corresponding environments and life histories. We analyzed four to five allozymic loci from three surveys of the same sites, spanning a 14-year period. An experimental design including three localities with two transects per locality and three shore levels allowed studying temporal and spatial population structure and estimation of effective population sizes (N(e)), neighborhood sizes (N(n)), and migration rates (m). Genetic differentiation was significantly lower in RB populations (theta(ST) = 0.067) than in SU ones (theta(ST) = 0.124). Mean estimates of N(e), N(n), and m did not differ significantly between ecotypes, but local ecotype differences in migration between the two closest localities (larger migration rates in RB than in SU populations) could explain the pattern in population differentiation.