Cliffs Used as Communal Roosts by Andean Condors Protect the Birds from Weather and Predators

The quality and availability of resources influence the geographical distribution of species. Social species need safe places to rest, meet, exchange information and obtain thermoregulatory benefits, but those places may also serve other important functions that have been overlooked in research. We use a large soaring bird that roosts communally in cliffs, the Andean condor (Vultur gryphus), as a model species to elucidate whether roost locations serve as a refuge from adverse weather conditions (climatic refuge hypothesis, CRH), and/or from predators or anthropogenic disturbances (threats refuge hypothesis, TRH). The CRH predicts that communal roosts will face in the opposite direction from where storms originate, and will be located in climatically stable, low precipitation areas. The TRH predicts that communal roosts will be large, poorly accessible cliffs, located far from human-made constructions. We surveyed cliffs used as communal roosts by condors in northwestern Patagonia, and compared them with alternative non-roosting cliffs to test these predictions at local and regional scales. We conclude that communal roosting places provide refuge against climate and disturbances such as, for instance, the threats of predators (including humans). Thus, it is not only the benefits gained from being aggregated per se, but the characteristics of the place selected for roosting that may both be essential for the survival of the species. This should be considered in management and conservation plans given the current scenario of global climate change and the increase in environmental disturbances.     

Synthetic peptides and fluorogenic substrates related to the reactive site sequence of Kunitz-type inhibitors isolated from Bauhinia: interaction with human plasma kallikrein

We have previously described Kunitz-type serine proteinase inhibitors purified from Bauhinia seeds. Human plasma kallikrein shows different susceptibility to those inhibitors. In this communication, we describe the interaction of human plasma kallikrein with fluorogenic and non-fluorogenic peptides based on the Bauhinia inhibitors' reactive site. The hydrolysis of the substrate based on the B. variegata inhibitor reactive site sequence, Abz-VVISALPRSVFIQ-EDDnp (Km 1.42 microM, kcat 0.06 s(-1), and kcat/Km 4.23 x 10(4) M(-1) s(-1)), is more favorable than that of Abz-VMIAALPRTMFIQ-EDDnp, related to the B. ungulata sequence (Km 0.43 microM, kcat 0.00017 s(-1), and kcat/Km 3.9 x 10(2) M(-1) s(-1)). Human plasma kallikrein does not hydrolyze the substrates Abz-RPGLPVRFESPL-EDDnp and Abz-FESPLRINIIKE-EDDnp based on the B. bauhinioides inhibitor reactive site sequence, the most effective inhibitor of the enzyme. These peptides are competitive inhibitors with Ki values in the nM range. The synthetic peptide containing 19 amino acids based on the B. bauhinioides inhibitor reactive site (RPGLPVRFESPL) is poorly cleaved by kallikrein. The given substrates are highly specific for trypsin and chymotrypsin hydrolysis. Other serine proteinases such as factor Xa, factor XII, thrombin and plasmin do not hydrolyze B. bauhinioides inhibitor related substrates.     

Cytometry and flow cytometry of 4',6-diamidino-2-phenylindole (DAPI)-stained suspensions of nuclei released from fresh and fixed tissues of plants

Cytometry and flow cytometry were used to study characteristics of fluorescence of the DNA-DAPI complex in nuclei released from different fresh and formaldehyde-fixed pea ( Pisum sativum L. cv. Lincoln) tissues. The two methods of isolation are compared and discussed as well as their possible use for quantitative analysis of DNA in plant tissues. With fixed tissues it is possible to obtain a number of nuclei sufficient for the flow cytometric analysis, even using small amounts of plant tissue.     

The role of nurse plants in the establishment of shrub seedlings in the semi-arid subtropical Andes

In the nurse plant syndrome, or nurse association, seedlings (beneficiaries) are associated with adult shrubs/trees (benefactors). This phenomenon has been documented in several regions of the planet. Abiotic stress amelioration (one mechanism of facilitation) is one of the causes of this association. Most of the studies addressing the nurse syndrome have been conducted on spatial scales of a few hectares and have focused on only one or a few species. Moreover, there is an almost complete lack of studies addressing the incidence and characteristics of the nurse phenomenon in the arid Andes of South America. We undertook a first approximation to the study of facilitation in these ecosystems. The study was conducted at local and regional scales and involved the assessment of the spatial distribution of juveniles (seedlings and saplings) of 51 populations of 16 shrub and 12 cactus species in relation to shrub cover at 20 localities of the Prepuna (subtropical Andes of Bolivia and Argentina, 20–26°S). In terms of spatial distribution, the juveniles of most of the populations of shrubs studied were distributed both under the shrubs and in open spaces, thereby showing an apparent indifference to microhabitat. Globose and opuntioid cacti were preferentially distributed below the canopies of shrubs and were usually more associated with the dominant shrub species, which stood out as better potential nurses. The pattern was consistent throughout the region, including the more mesic and arid localities. The fact that Prepuna woody species are capable of establishing in open spaces would confer this region a greater resilience. Our findings further suggest that community dynamics in arid and semi-arid environments are more variable than previously thought.     

Alternative Nonallelic Deletion Is Constitutive of Ruminant αs1-Casein

Multiple forms of α_s1-casein were identified in the four major ruminant species by structural characterization of the protein fraction. While α_s1-casein phenotypes were constituted by a mixture of at least seven molecular forms in ovine and caprine species, there were only two forms in bovine and water buffalo species. In ovine and caprine forms the main component corresponded to the 199-residue-long form, and the deleted proteins differed from the complete one by the absence of peptides 141–148, 110–117, or Gln78, or a combination of such deletions. The deleted segments corresponded to the sequence regions encoded by exons 13 and 16, and by the first triplet of exon 11 (CAG), suggesting that the occurrence of the short protein forms is due to alternative skipping, as previously demonstrated for some caprine and ovine phenotypes. The alternative deletion of Gln78 in α_s1-casein, the only form common to the milk of all the species examined and located in a sequence region joining the polar phosphorylation cluster and the hydrophobic C-terminal domain of the protein, may play a functional role in the stabilization of the milk micelle structure.     

Effects of general,specific and combined warm-up on explosive muscular performance

The purpose of this study was to compare the acute effects of general, specific and combined warm-up (WU) on explosive performance. Healthy male (n = 10) subjects participated in six WU protocols in a crossover randomized study design. Protocols were: passive rest (PR; 15 min of passive rest), running (Run; 5 min of running at 70% of maximum heart rate), stretching (STR; 5 min of static stretching exercise), jumping [Jump; 5 min of jumping exercises – 3x8 countermovement jumps (CMJ) and 3x8 drop jumps from 60 cm (DJ60)], and combined (COM; protocols Run+STR+Jump combined). Immediately before and after each WU, subjects were assessed for explosive concentric-only (i.e. squat jump – SJ), slow stretch-shortening cycle (i.e. CMJ), fast stretch-shortening cycle (i.e. DJ60) and contact time (CT) muscle performance. PR significantly reduced SJ performance (p =0.007). Run increased SJ (p =0.0001) and CMJ (p =0.002). STR increased CMJ (p =0.048). Specific WU (i.e. Jump) increased SJ (p =0.001), CMJ (p =0.028) and DJ60 (p =0.006) performance. COM increased CMJ performance (p =0.006). Jump was superior in SJ performance vs. PR (p =0.001). Jump reduced (p =0.03) CT in DJ60. In conclusion, general, specific and combined WU increase slow stretch-shortening cycle (SSC) muscle performance, but only specific WU increases fast SSC muscle performance. Therefore, to increase fast SSC performance, specific fast SSC muscle actions must be included during the WU.     

Developmentally Arrested Precursors of Pontine Neurons Establish an Embryonic Blueprint of the Drosophila Central Complex

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Efficacy of curcumin in the treatment of experimental vulvovaginal candidiasis

BackgroundCandida albicans is the main agent that causes vulvovaginal candidiasis. Resistance among isolates to azole antifungal agents has been reported.AimsDue to the well-known antifungal potential of curcumin, the purpose of this work was to evaluate the in vitro anticandidal activity of curcumin and its effect in the treatment of experimental vulvovaginal candidiasis.MethodsThe anticandidal activity of curcumin was investigated against eight Candida strains by the broth microdilution assay, and its mechanism of action was evaluated by testing the binding to ergosterol. Then, the effect of curcumin in the treatment of vulvovaginal candidiasis was evaluated in an immunosuppressed, estrogen treated rat model.ResultsCurcumin showed minimum inhibitory concentration values of 125–1000 μg/ml, and the best result was observed against Candida glabrata. The compound was shown to be able to bind to the ergosterol present in the membrane, event that may be the mechanism of action. In addition, in the in vivo model of vulvovaginal candidiasis with C. albicans, treatments reduced the vaginal fungal burden in infected rats after seven days of treatment with different doses.ConclusionsCurcumin could be considered a promising effective antifungal agent in the treatment of vulvovaginal candidiasis.     

Antinoceptive and Anti-inflammatory Activities of the Ethanolic Extract,Fractions and Flavones Isolated from Mimosa tenuiflora (Willd.) Poir (Leguminosae)

The bark of Mimosa tenuiflora (Willd.) Poiret (Leguminosae family), popularly known as “jurema preta” in Brazil, is used by the population of Contendas of Sincorá (Bahia State, Brazil) for the treatment of coughs and wound healing. Thus, the aim of this study was to evaluate the antinociceptive and anti-inflammatory activities of the bark ethanol extract (EEMT) and solvent soluble fractions (hexane—H, DCM—D, EtOAc—E and BuOH—B) of the extract in vivo. Additionally, we synthesized 5,7-dihidroxy-4’-methoxyflavanone (isosakuranetin) and isolated the compound sakuranetin, and both compounds were also tested. The anti-inflammatory and antinociceptive assays performed were: writhing test; nociception induced by intraplantar formalin injection; leukocyte recruitment to the peritoneal cavity; evaluation of vascular permeability (Evans blue test); and evaluation of mechanical hypernociception (von Frey test). Production of TNF-α, IL-10, myeloperoxidase and the expression of ICAM-1 were also evaluated. Statistical analysis was performed by one-way ANOVA followed by the Bonferroni post-test (n = 8), with P < 0.05. The EEMT showed antinociceptive activities in writhing test (100–200 mg/kg), in the second phase of the formalin test (50–200 mg/kg), and in mechanical hypernociception (100 mg/kg). EEMT showed an anti-inflammatory effect by reducing neutrophil migration to the peritoneal cavity and in the plantar tissue detected by the reduction of myeloperoxidase activity (100 mg/kg), reduction of IL-10 levels and expression of ICAM-1 in the peritoneal exudate and the mesentery (100 mg/kg), respectively. The four soluble EEMT fractions showed good results in tests for antinociceptive (H, D, E, B) and anti-inflammation (H, D, E). Only sakuranetin showed reduction of the writhing and neutrophil migration (200 mg/kg). Thus, the EEMT and soluble fractions of M. tenuiflora bark demonstrated great antinociceptive and anti-inflammatory activities, as also sakuranetin. More studies should be conducted to elucidate the mechanism of action of this compound. To the best of our knowledge, this is the first report on the antinociceptive activity of the M. tenuiflora fractions and the bioactive isolated compound sakuranetin in vivo.