Spatial and interspecific differences of trace element concentrations in the feathers of pelagic and coastal seabirds from the Northeast Atlantic Ocean and the Western Mediterranean Sea.

Coastal ecosystems face increasing contamination threats due to urbanisation and consequent human pressure worldwide. This study assessed exposure to 15 trace elements (Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sr, Ti, V, Zn) across the Northeast Atlantic and the western Mediterranean in pelagic shearwaters (Calonectris borealis and C. diomedea) and coastal gulls (Ichthyaetus audouinii and Larus michahellis).

Mercury contamination in gull chicks raised in natural vs. urban habitats.

Anthropogenic activities have increased pressure on marine ecosystems through the continuous overflow of pollutants like mercury (Hg). Seabirds, particularly chicks, serve as effective local bioindicators of marine ecosystem health. This study assessed the influence of trophic ecology (inferred from δC and δN values) and colony location on Hg concentrations in the blood of yellow-legged (YLG, Larus michahellis) and Audouin's (AG, Ichthyaetus audouinii) gull chicks raised in natural (YLG, AG) vs.

The role of seabird foraging strategies on the uptake of mercury: A case study using gulls and shearwaters from the Portuguese coast.

Mercury (Hg) is a non-essential element that bioaccumulates and biomagnifies in food webs through site-specific biogeochemical processes. Seabirds are valuable bioindicators of Hg contamination, yet certain regions, like the Portuguese coast, remain underrepresented. This study measured Hg concentrations in the blood of yellow-legged gulls (Larus michahellis), Audouin's gulls (Ichthyaetus audouinii), and Cory's shearwaters (Calonectris borealis) breeding along the Portuguese coastline.

Calonectris shearwaters reveal a gradient of mercury contamination along the Atlantic and Mediterranean waters of the Iberian Peninsula.

This study examines blood mercury (Hg) concentrations in Calonectris spp. shearwaters from three colonies along the Atlantic and Mediterranean waters of the Iberian Peninsula (southwestern Europe), investigating their relationship with foraging ecology through GPS tracking and stable isotopes (δN and δC) data during the breeding season. Hg levels exhibited a spatial gradient, increasing from the Atlantic Ocean (1.

Assessing the impacts of trace element contamination on the physiology and health of seabirds breeding along the western and southern coasts of Portugal.

Coastal seabirds serve as sentinels of ecosystem health due to their vulnerability to contamination from human activities. However, our understanding on how contaminant burdens affect the physiological and health condition of seabirds is still scarce, raising the uncertainty on the species' vulnerability vs tolerance to environmental contamination. Here, we quantified 15 Trace Elements (TE) in the blood of gull (yellow-legged gull Larus michahellis and Audouin's gull Ichthyaetus audouinii) and shearwater (Cory's shearwater Calonectris borealis) adults, breeding in five colonies along the Portuguese coastline.

Omega-3 enriched chick diet reduces the foraging areas of breeders in two closely related shearwaters from contrasting marine environments.

Seabirds have evolved several life-history characteristics to help buffer environmental stochasticity. However, particularly during the breeding season, seabirds may be affected by reductions in prey availability and localised oceanographic conditions caused by variations in the environment. The increase in sea surface temperature, triggered by accelerated global warming, is impairing phytoplankton production of omega-3 fatty acids (FAs).

DNA metabarcoding to assess prey overlap between tuna and seabirds in the Eastern tropical Atlantic: Implications for an ecosystem-based management.

Overfishing has been drastically changing food webs in marine ecosystems, and it is pivotal to quantify these changes at the ecosystem level. This is especially important for ecosystems with a high diversity of top predators such as the Eastern Atlantic marine region. In this work we used high-throughput sequencing methods to describe the diet of the two most abundant tuna species, the Skipjack tuna (Katsuwonus pelamis) and the Yellowfin tuna (Thunnus albacares), highly targeted by fisheries off west Africa.

Foraging costs drive within-colony spatial segregation in shearwaters from two contrasting environments in the North Atlantic Ocean.

Foraging spatial segregation is frequent in central-place foragers during the breeding season, but very few studies have investigated foraging spatial segregation between adjacent sub-colonies. Here, we assessed for within-colony differences in the at-sea distribution, habitat use, trophic ecology and chick growth data of two Calonectris colonies differing in size, and breeding in two different environments in the North Atlantic Ocean. For this, we GPS tracked 52 Cory's shearwaters (Calonectris borealis) breeding in 2 small sub-colonies at Berlenga Island (Portugal) and 59 Cape Verde shearwaters (Calonectris edwardsii) breeding in 2 sub-colonies differing greatly in size at Raso Islet (Cabo Verde), over 2 consecutive breeding seasons (2017-2018), during chick-rearing.

Year-round at-sea distribution and trophic resources partitioning between two sympatric Sulids in the tropical Atlantic.

In the oligotrophic tropical marine environment resources are usually more patchily distributed and less abundant to top predators. Thus, spatial and trophic competition can emerge, especially between related seabird species belonging to the same ecological guild. Here we studied the foraging ecology of two sympatric species-brown booby (BRBO) Sula leucogaster (breeding) and red-footed boobies (RFBO) Sula sula (non-breeding)-at Raso islet (Cabo Verde), across different seasons.

Inter-annual changes in oceanic conditions drives spatial and trophic consistency of a tropical marine predator.

Pelagic seabirds exhibit plasticity in foraging characteristics in relation to oceanographic conditions. This should be particularly relevant in tropical marine environments where food resources are naturally more unpredictable. We studied how inter-annual variations (2013-2018) in tropical oceanographic conditions (driver of oceanic productivity) can influence the spatial and trophic ecology of Cape Verde shearwater (Calonectris edwardsii) during the breeding season.

Onychomycosis by Scytalidium dimidiatum: report of two cases in Santa Catarina, Brazil.

Onychomycoses constitute pathologies frequently seen in dermatological practice worldwide. Usually, they are caused by two groups of pathogenic fungi: dermatophytes and yeasts of the Candida genus. However, in a small fraction of the cases, the etiologic agents comprise nondermatophyte molds, belonging to several genera and species.

Evaluation of enzyme-linked immunosorbent and alternative assays for detection of HIV antibodies using panels of Brazilian sera.

Sera from 472 Brazilian subjects, confirmed to be either positive or negative for HIV antibodies and comprising the total clinical spectrum of HIV infection, were utilized in the evaluation of six commercially available enzyme-linked immunosorbent assays (ELISA), as well as of four alternative assays, namely indirect immunofluorescence (IIF), passive hemagglutination (PHA), dot blot and Karpas AIDS cell test. The sensitivities ranged from 100% (Abbott and Roche ELISA) to 84.2% (PHA) and the specificities ranged from 99.

Patterns of serologic response to human immunodeficiency virus type 1 (HIV-1) in Brazilians with different clinical forms of HIV infection.

In order to investigate the IgG HIV-1 antibodies reactivity to structural components of the virus, 85 sera from infected Brazilians, comprising the total spectrum of HIV infection, were analysed by Western blot assay. The sera were confirmed as being positive to HIV with enzyme linked immuno assay (ELISA) and indirect immunofluorescence (IIF). Although the sera from patients reacted less intensively to the gag polypeptide of 55 KDa, no distinctive antigen reaction patterns were observed between sera patients with different clinical forms.

Trypanosoma cruzi: identification of specific epimastigote antigens by human immune sera.

Soluble antigens from epimastigotes of Trypanosoma cruzi were analyzed by western blot in terms of their reactivity with sera from patients with Chagas' disease. In addition, sera from patients with visceral (AVL) and tegumental leishmaniasis (ATL) were also tested in order to identify cross-reactivities with Trypanosoma cruzi antigens. Twenty eight polypeptides with molecular weights ranging from 14 kDa to 113 kDa were identified with sera from Chagas' disease patients.

A simple procedure for obtaining large amounts of HIV antigens for serodiagnostic purposes.

The established method of purifying human immunodeficiency virus (HIV) involves centrifuging the lysates of infected cells onto a sucrose gradient. This article reports an alternative methodology for purifying large amounts of HIV antigens that avoids the need for expensive equipment such as an ultracentrifuge and requires no purification gradient. These semipurified antigens have been used to perform a "homemade" confirmatory Western blot assay that produced reactivity comparable to that obtained with a commercial Western blot assay.

Isolation and antigenic characterization of human immunodeficiency virus (HIV) in Brazil.

A retrovirus infecting a Brazilian AIDS patient was isolated and characterized in terms of its reactivity with sera from individuals infected with human immunodeficiency viruses 1 and 2 (HIV-1 and HIV-2). The Western blot analysis revealed that the Brazilian isolate is very similar to the well characterized HIV-1 strain. The serum of the patient from whom the virus was isolated did not react with the 140 kDa envelope glycoprotein specific for HIV-2.

Dot enzyme immunoassay. A simple, cheap and stable test for antibody to human immunodeficiency virus (HIV).

A dot enzyme immunoassay for antibody to HIV has been developed and tested with a panel of positive and negative sera. It has proved to be of equal or greater sensitivity compared with a commercial ELISA kit, is simple and quick to perform, requires neither sophisticated equipment nor highly trained technical staff. The reagents are stable enough for postal distribution in tropical countries and, other than for the antigen, the costs are low, making it an appropriate test for use in the developing world when funds for expensive commercial kits are not available.