Contribution to the knowledge of the savanna and forb-rich communities of Pinar del Rio Province (Cuba)

Phytosociological analysis of savanna and forb-rich communities in the Pinar del Rio Province was done in the area of Remates de Guane; one locality lies on the seashore in the western part of the province. Altogether six associations were distinguished. Five of them, viz.Sclerio curtissii-Centelletum erectae, Schultezio guianensis-Rhynchosporetum fascicularis, Cassio diphyllae-Hypericetum stypheloidis, Polygalo squamifoliae-Dichromenetum seslerioidis andPhyllantho juncei-Aristidetum, all newly described in this paper, are classified into the order ofAcoelorapho-Colpothrinacetalia Bal.-Tul. inBal.-Tul. etCapote 1985 with two alliances. One association, thePaspalo debilis-Asteretum grisebachii Bal.-Tul. etCapote 1992, was put into the order ofAsteretalia grisebachii Bal.-Tul. inBal.-Tul. etCapote 1992 with one alliance bound to inland moving dunes. The plant composition reflects soil quality, above all the water regime. Very interesting is the presence of theByrsonimo crassifoliae-Andropogonetalia teneris-species in the association ofPolygalo-Dichromeneteum seslerioidis indicating the rich presence of stones in the upper part of the soil profile.     

A new savanna-like community of the sierra del rosario mountains,Cuba

This communication describes a new savanna-like community, theBletio purpureae-Andropogonetum gracilis Balátová-Tulá?ková etR. Capote ass. nov., found in the woodless eastern part of the Sierra del Rosario Mountains (western part of Cuba). From the phytosociological point of view, it belongs to the allianceAchlaenion piptostachyae Balátová-Tulá?ková all. nov., the orderAchlaenetalia piptostachyae Balátová-Tulá?ková ord. nov., and the classSclerio baldwinii-Andropogonetea gracilis Balátová-Tulá?ková cl. nov. In the area under study four subassociations were distinguished: theBletio-Andropogonetum typicum Balátová-Tulá?ková et.R. Capote subass. nov., theB.-A. rhynchosporetosum fascicularis Balátová-Tulá?ková etR. Capote subass. nov., theB.-A. cassietosum aeschynomenes Balátová-Tulá?ková etR. Capote subass. nov., and theB.-A. stenandrietosum droseroidis Balátová-Tulá?ková etR. Capote subass. nov.     

The Goat (Capra hircus) Mammary Gland Mitochondrial Proteome: A Study on the Effect of Weight Loss Using Blue-Native PAGE and Two-Dimensional Gel Electrophoresis

Seasonal weight loss (SWL) is the most important limitation to animal production in the Tropical and Mediterranean regions, conditioning producer’s incomes and the nutritional status of rural communities. It is of importance to produce strategies to oppose adverse effects of SWL. Breeds that have evolved in harsh climates have acquired tolerance to SWL through selection. Most of the factors determining such ability are related to changes in biochemical pathways as affected by SWL. In this study, a gel based proteomics strategy (BN: Blue-Native Page and 2DE: Two-dimensional gel electrophoresis) was used to characterize the mitochondrial proteome of the secretory tissue of the goat mammary gland. In addition, we have conducted an investigation of the effects of weight loss in two goat breeds with different levels of adaptation to nutritional stress: Majorera (tolerant) and Palmera (susceptible). The study used Majorera and Palmera dairy goats, divided in 4 sets, 2 for each breed: underfed group fed on wheat straw (restricted diet, so their body weight would be 15–20% reduced by the end of experiment), and a control group fed with an energy-balanced diet. At the end of the experimental period (22 days), mammary gland biopsies were obtained for all experimental groups. The proteomic analysis of the mitochondria enabled the resolution of a total of 277 proteins, and 148 (53%) were identified by MALDI-TOF/TOF mass spectrometry. Some of the proteins were identified as subunits of the glutamate dehydrogenase complex and the respiratory complexes I, II, IV, V from mitochondria, as well as numerous other proteins with functions in: metabolism, development, localization, cellular organization and biogenesis, biological regulation, response to stimulus, among others, that were mapped in both BN and 2DE gels. The comparative proteomics analysis enabled the identification of several proteins: NADH-ubiquinone oxidoreductase 75 kDa subunit and lamin B1 mitochondrial (up-regulated in the Palmera breed), Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-2 (up-regulated in the Majorera breed) and cytochrome b-c1 complex subunit 1, mitochondrial and Chain D, Bovine F1-C8 Sub-Complex Of Atp Synthase (down-regulated in the Majorera breed) as a consequence of weight loss.     

The Association of Tau-Like Proteins with Vimentin Filaments in Cultured Cells

There is increasing evidence that the different polymers that constitute the cytoskeleton are interconnected to form a three-dimensional network. The macromolecular interaction patterns that stabilize this network and its intrinsic dynamics are the basis for numerous cellular processes. Within this context,in vitrostudies have pointed to the existence of specific associations between microtubules, microfilaments, and intermediate filaments. It has also been postulated that microtubule-associated proteins (MAPs) are directly involved in mediating these interactions. The interactions of tau with vimentin filaments, and its relationships with other filaments of the cytoskeletal network, were analyzed in SW-13 adenocarcinoma cells, through an integrated approach that included biochemical and immunological studies. This cell line has the advantage of presenting a wild-type clone (vim+) and a mutant clone (vim−) which is deficient in vimentin expression. We analyzed the cellular roles of tau, focusing on its interactions with vimentin filaments, within the context of its functional aspects in the organization of the cytoskeletal network. Cosedimentation experiments of microtubular protein with vimentin in cell extracts enriched in intermediate filaments, combined with studies on the direct interaction of tau with nitrocellulose-bound vimentin and analysis of tau binding to vimentin immobilized in single-strand DNA affinity columns, indicate that tau interacts with the vimentin network. These studies were confirmed by a quantitative analysis of the immunofluorescence patterns of cytoskeleton-associated tubulin, tau, and vimentin using flow cytometry. In this regard, a decrease in the levels of tau associated to the cytoskeletal network in the vim− cell mutant compared with the wild-type clones was observed. However, immunofluorescence data on SW-13 cells suggest that the absence of a structured network of vimentin in the mutant vim− cells does not affect the cytoplasmic organization formed by microtubules and actin filaments, when compared with the wild-type vim+ cells. These studies suggest that tau associates with vimentin filaments and that these interactions may play a structural role in cells containing these filaments.     

Mitochondrial DNA diversity and origins of South and Central American goats

We have analysed the genetic diversity of South and Central American (SCA) goats by partially sequencing the mitochondrial control region of 93 individuals with a wide geographical distribution. Nucleotide and haplotype diversities reached values of 0.020 ± 0.00081 and 0.963 ± 0.0012 respectively. We have also observed a rather weak phylogeographic structure, with almost 69% of genetic variation included in the within-breed variance component. The topology of a median-joining network analysis including 286 European, Iberian, Atlantic and SCA mitochondrial sequences was very complex, with most of the haplotypes forming part of independent small clusters. SCA sequences showed a scattered distribution throughout the network, and clustering with Spanish and Portuguese sequences occurred only occasionally, not allowing the distinguishing of a clear Iberian signature. Conversely, we found a prominent cluster including Canarian, Chilean, Argentinian and Bolivian mitochondrial haplotypes. This result was independently confirmed by constructing a Bayesian phylogenetic tree (posterior probability of 0.97). Sharing of mitochondrial haplotypes by SCA and Canarian goats suggests that goat populations from the Atlantic archipelagos, where Spanish and Portuguese ships en route to the New World used to stow food and supplies, participated in the foundation of SCA caprine breeds.     

Structure and injuries of octocoral communities (Octocorallia: Alcyonacea) of Ecological Reserve Siboney-Juticí, Santiago de Cuba, Cuba

In the spur-and-groove reefs of the Ecological Reserve Siboney-Juticí (Southeast Cuba) octocorals are one of the predominant components of the sessile fauna. Main objectives of the present paper are characterizing the composition, structure and conservation status of the octocoral communities and assessing on the prevailing environmental conditions in the study area. For data collection, six sampling sites were located every 2-3 km ranging from 12 m to 17 m depth along the spur-and-groove reefs. In each site, 22-26 lm2 quadrants were zigzag arranged every 2 m. The density of colonies was determined per site. The severity degree and predictability of environmental conditions were inferred by using the Heterogeneity and Equitability indexes, respectively. Hydrodynamic stress and the Comparative Pollution Index were also assessed. Current affectations of the octocoral communities were also determined and classified into four main categories: mechanical damage, diseases, predation and invertebrate and macroalgae overgrowth. As a result, 25 species represented by 752 colonies were recorded and Eunicea flexuosa and Gorgonia ventalina were the most abundant. The occurrence of Eunicea succinea forma succinea constituted the first report for Eastern Cuba. Site densities ranged from 3.58 +/- 1.84 to 7.58 +/- 2.16 colonies/m2 and considered from moderate to low. The biggest densities were reported at both sides of the San Juan River mouth. Despite of the composition and structure of the octocoral communities, low to high hydrodynamic stress and low and moderate levels of contamination were inferred, it is likely that these indexes could have been overestimated due to the sensitivity of the indicator species to other factors such as sedimentation. The environmental conditions were mostly favorable and stable. In general, the number of dead colonies was low and mostly caused by the detachment of the substrate and overgrowth of Millepora alcicornis. Injuries were mainly brought about by mechanical damage, followed by coenenchyme loss, predation by Cyphoma gibbosum and macroalgae overgrowth. On the other hand, negative effects by Hermodice carunculata predation, bleaching, Red Band and Black Band Disease were not observed. Among sampled species, G. ventalina colonies were the most severely damaged within the community. As a whole, octocoral communities of spur-and-groove reefs in the Ecological Reserve Siboney-Juticí showed a good conservation status.     

Effects of a mixture of fatty acids from sugar cane (Saccharum officinarum L.) wax oil in two models of inflammation: Zymosan-induced arthritis and mice tail test of psoriasis

A mixture of fatty acids obtained from sugar cane (Saccharum officinarum L.) wax oil (FAM), in which the main constituents are palmitic, oleic, linoleic, and linolenic acids, was evaluated in two models of inflammation: zymosan-induced arthritis and in the tail test for psoriasis, both on mice. In the first model, FAM significantly reduced zymozan-induced increase of beta glucuronidase (DE(50) 90+/-7 mg/kg). Histopathological studies showed inhibition in cellular infiltration and reduction of synovial hyperplasia and synovitis, whereas in the second test, histopathological and ultrastructural studies showed that topical application of FAM induced orthokeratosis with the presence of keratohyalin granules in the previously parakeratotic adult mouse tail, and without effects on epidermal thickness. The ED(50) of FAM in this model was 155+/-10 mg. The results of our studies showed that topical application of FAM exerts an important anti-inflammatory activity in both tests without evidence of irritant effects. The anti-inflamatory effects exerted by FAM may be due to its inhibitory effects on arachidonic acid metabolism. To our knowledge, this is the first report on the anti-inflammatory effect of sugar cane by-products in experimental models of arthritis and psoriasis.     

Quantitative evaluation of mammalian skeletal muscle as a heterologous protein expression system

The production of mammalian proteins in sufficient quantity and quality for structural and functional studies is a major challenge in biology. Intrinsic limitations of yeast and bacterial expression systems preclude their use for the synthesis of a significant number of mammalian proteins. This creates the necessity of well-identified expression systems based on mammalian cells. In this paper, we demonstrate that adult mammalian skeletal muscle, transfected in vivo by electroporation with DNA plasmids, is an excellent heterologous mammalian protein expression system. By using the fluorescent protein EGFP as a model, it is shown that muscle fibers express, during the course of a few days, large amounts of authentic replicas of transgenic proteins. Yields of approximately 1mg/g of tissue were obtained, comparable to those of other expression systems. The involvement of adult mammalian cells assures an optimal environment for proper protein folding and processing. All these advantages complement a methodology that is universally accessible to biomedical investigators and simple to implement.     

Photosynthesis and carbon metabolism in plantain (Musa AAB) plantlets growing in temporary immersion bioreactors and during ex vitro acclimatization

Summary The photosynthetic capacity changes and the main enzymatic systems related to carbon metabolism were investigated during the in vitro culture of plantain shoots (Musa AAB cv. CEMSA 3/4) in temporary immersion bioreactors (TIB) and their subsequent acclimatization. The maximal rate of photosynthesis (Pn), transpiration, and the activity of the carbon metabolism enzymes phosphoenolpyruvate carboxylase (PEPC), acid invertase (AI), pyruvate kinase (PK) and sucrose phosphate synthase (SPS) were measured every 7 d during the 21 d of elongation in TIB, and the following 42 d of acclimatization. Sucrose content in the liquid medium and in the leaves was also determined. The most significant changes in plant growth were observed during acclimatization. During the in vitro stage photosynthesis was limited (4–6 μmol CO₂m⁻²s⁻¹); the photosynthetic rate however increases rapidly and significantly as soon as in vitro culture is over during acclimatization. PEPC activity increased during the whole evaluation period. The highest levels were achieved around days 42 and 56. PK and SPS activities were optimal during the first weeks in acclimatization (28–35 d), while AI increased at the beginning of the elongation phase (7 d), and later at the end of the acclimatization (49–63 d). The relationships between morphological parameters, photosynthetic capacity of the plantlets and the carbon metabolism enzymes during both phases of the culture are discussed.     

Variability in esterases of Metarhizium anisopliae

The variability in esterases of the entomogenous fungus Metarhizium anisopliae was determined electrophoretically on 8.5% polyacrylamide gel. Ten isolates from diverse taxonomic groups of insects were analyzed. The electrophoretic analysis showed differences and similarities between these isolates and it was possible to distinguish six different patterns. The results obtained show a great polymorphism for the esterase system of M. anisopliae.