Chicken feather keratin peptides for the control of keratinocyte migration

FAO estimates that in 2030 the poultry meat production could reach 120 million tons, which is a challenge in terms of waste management. Feathers are mainly composed of keratin, an important biomaterial. Using feathers as a source of keratin will minimize the waste generated, while contributing to supply an important material for several industries, such as pharmaceutical and biomedical. The peptides were extracted from the feathers by microbial degradation. In this study, we evaluated the peptides effect on keratinocyte metabolic activity and migration. The influence of these peptides on non-activated and activated macrophages was also assessed. It was demonstrated that depending on the keratin peptide fraction in contact with keratinocytes, it is possible to modulate the migration rate of the keratinocytes. Peptide fraction with low molecular weight increases migration, while peptides with a high range of molecular sizes decreases it. Some peptide fractions induce the secretion of TNF- in non-activated macrophages and not on activated macrophages, demonstrating that these peptides should only be placed in contact with cells, in the context of an ongoing inflammatory process. This work is a step forward on the understanding of keratin peptides influence on keratinocytes and immune cells system cells, macrophages.This research was funded by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit. It was also was financed by the Portuguese Mass Spectrometry Network, integrated in the National Roadmap of Research Infrastructures of Strategic Relevance (ROTEIRO/0028/2013; LISBOA-01-0145-FEDER-022125) and the MAC 2014-2020-MAC/1.1b/042-INTERREG V A España-Portugal, “BIOTRANSFER 2: Transferencia de la investigación biotecnológica orientada a rentabilidad empresarial y movilización de flujos de negocio 2”.info:eu-repo/semantics/publishedVersio

Longitudinal distribution and lateral pattern of megalopal settlement and juvenile recruitment of Carcinus maenas (L.) (Brachyura, Portunidae) in the Mira River Estuary, Portugal

Settlement is a critical process in the life history of crabs, and thus affecting the abundance, distribution and structure of estuarine communities. The spatial pattern of settlement of megalopae of the shore crab Carcinus maenas along a longitudinal estuarine gradient (Mira River Estuary, Portugal) was examined, as well as its effects on the juvenile population. To measure megalopal settlement, four replicate collectors were deployed in six equally spaced stations along the estuarine axis. Juveniles were collected on the same locations with a quadrat randomly deployed on the substrate. To assess fine-scale megalopal settlement within a curved region of the estuary, replicate collectors were deployed on both margins along Moinho da Asneira curve. Megalopae settled differently along the six longitudinal points, with a tendency to attenuate their settlement upstream. Within the curved region, megalopae preferentially settled on the left margin collectors, probably due to the weaker velocity speeds felt on this margin. Concerning the overall juvenile density, there were significant differences among the stations distributed along the estuary, but they did no reflect a longitudinal dispersion attenuation pattern. Size-frequency distribution of the juvenile population showed that the average size is higher on the left margin. Recruits (carapace length between 1.0 mm and 3.4 mm) were more abundant on the upstream stations. Density of early juveniles (3.4 mme6.5 mm) and juveniles (6.5 mme10 mm) was more stable throughout the estuary axis than that of recruits. This distribution pattern may result from tidal excursion processes or mechanisms to avoid biotic interactions, such as predation and competition

Ultrastructure and cytochemistry of Eucalyptus globulus(Myrtaceae) pollen grain

The morphology, ultrastructure and cytochemistry of Eucalyptus globulusmature pollen were investigated using light (LM), scanning electron (SEM) and transmission electron microscopy (TEM). The pollen morphology is typically myrtaceous with a suite of characters that allows its distinction from the pollen of other Eucalyptusspecies. The exine consists of a thick endexine and a massive ectexine with hardly distinguishable columellae. The endexine is 2-layered towards the apertural regions where the inner and spongy-granulate layer forms a continuous colpus membrane and a thinner pore membrane. Under the pores the intine is 3-layered forming complex onci. The spindle-shaped generative cell (GC) is deeply undulated and located in a cup-shaped depression of the vegetative cell (VC) nucleus. In the dense VC cytoplasm the main storage reserves are lipid bodies and insoluble carbohydrates in the cytosol, although proteins are also present. The most characteristic feature of the VC cytoplasm is the extremely well-developed rough endoplasmic reticulum (RER), which forms extensive stacks filling large areas of the central cytoplasm. Single RER cisternae are also scattered throughout the cytoplasm, most of them establishing an intimate association with lipid bodies, storage vacuoles, the VC plasmalemma and a few proplastids. The physiological significance of the RER stacks and of the RER cisternae association with other cell components, as well as the structure and function of an endomembrane compartment, found only in the freeze-fixed pollen, are discussed.http://www.informaworld.com/10.1080/0017313080192336

On the growth of Iberian firms: An empirical analysis

The growth dynamics of firms have been object of numerous studies by econophysicists. The vast majority of these studies was done for large developed countries including the United States of America (US), France and Italy. These studies were conducted for countries with strong economies and whose business fabric has different characteristics from countries such as Portugal or Spain, with more large-sized firms and less micro-sized firms. It is thus important to study the growth dynamics of firms in Portugal and Spain, countries with economies that typically display anemic growth indexes and have a larger percentage of micro-sized firms. Considering two large samples of Portuguese and Spanish firms, we find that the size distribution of firms is well fitted by the generalized Pareto distribution. Moreover, the distribution of Iberian firms annual growth rates is best approximated by the Cauchy distribution rather than the Laplace distribution. Firms growth standard deviation conditional on size is well approximated by power-law relationships with a scaling exponent close to 1/2 for micro/small-sized firms and close to 0 for medium/large-sized firms

Ultrastructure and cytochemistry of Eucalyptus globulus(Myrtaceae) pollen grain

The morphology, ultrastructure and cytochemistry of Eucalyptus globulusmature pollen were investigated using light (LM), scanning electron (SEM) and transmission electron microscopy (TEM). The pollen morphology is typically myrtaceous with a suite of characters that allows its distinction from the pollen of other Eucalyptusspecies. The exine consists of a thick endexine and a massive ectexine with hardly distinguishable columellae. The endexine is 2-layered towards the apertural regions where the inner and spongy-granulate layer forms a continuous colpus membrane and a thinner pore membrane. Under the pores the intine is 3-layered forming complex onci. The spindle-shaped generative cell (GC) is deeply undulated and located in a cup-shaped depression of the vegetative cell (VC) nucleus. In the dense VC cytoplasm the main storage reserves are lipid bodies and insoluble carbohydrates in the cytosol, although proteins are also present. The most characteristic feature of the VC cytoplasm is the extremely well-developed rough endoplasmic reticulum (RER), which forms extensive stacks filling large areas of the central cytoplasm. Single RER cisternae are also scattered throughout the cytoplasm, most of them establishing an intimate association with lipid bodies, storage vacuoles, the VC plasmalemma and a few proplastids. The physiological significance of the RER stacks and of the RER cisternae association with other cell components, as well as the structure and function of an endomembrane compartment, found only in the freeze-fixed pollen, are discussed.http://www.informaworld.com/10.1080/0017313080192336

Is the quantity of orbicules released by Dactylis glomerataand Cynosurus echinatus(Poaceae) big enough to play an allergenic role?

Orbicule characteristics of Dactylis glomerataand Cynosurus echinatus(Poaceae) were investigated using light (LM), scanning electron (SEM) and transmission electron microscopy (TEM). Based on SEM micrographs, the number of orbicules per 100 µm2 of the locule wall surface was determined in both dehisced and undehisced anthers and was further compared statistically. A total of 100 pollen grains were examined using SEM in search for orbicules attached to the pollen exine. Orbicules were not found distributed freely in the anther locules. They were attached to the locule wall surface through sporopolleninous fibrils, the orbicule wall being firmly embedded in, and often in continuity with the thin layer of sporopollenin lining each locule. The orbicule density on the locule wall surface of both the dehisced and undehisced anthers did not differ significantly. Only a few orbicules were seen attached to the pollen exine in both species. It is concluded that orbicules are not easily removed from the surface of the locule wall and, consequently, that the number of orbicules emitted from the two grass species is too low to play a significant role in triggering allergic diseases.http://www.informaworld.com/10.1080/0017313070144806

Non-Selective Toxicological Effects of the Insect Juvenile Hormone Analogue Methoprene. A Membrane Biophysical Approach

Abstract The Gram-positive bacterium, Bacillus stearothermophilus, was used as a model organism to identify the non-selective toxic effects of the currently used insecticide methoprene (isopropyl(2E,4E)-11-methoxy-3,7,11-trimethyl-2,4-dodecadienoate). A significant decrease of the yield of bacterial cultures and a premature appearance of ultrastructural abnormalities in cells cultured in the presence of the insecticide were taken as indicators of cytotoxicity. A putative correlation of this cytotoxicity with methoprene-induced perturbations on membrane lipid organization was investigated, using differential scanning calorimetry and the fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) and its propionic acid derivative (DPH–PA). The membrane physical effects depended on the lipid bilayer composition and packing. The most striking effect was a progressive broadening and shifting to lower temperatures, with increasing methoprene concentrations, of the main transition phase of the dimyristoyl- or dipalmitoylphosphatidylcholine bilayers and of the lateral phase separation of liposomes reconstituted with the lipid extracts of B. stearothermophilus