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PubMed2004

Organochlorine compounds in tissues of swordfish (Xiphias gladius) from Mediterranean Sea and Azores islands.

Polychlorobiphenyls (PCB) and organochlorine (OC) pesticides are endocrine-disrupting chemicals (EDCs). The Italian Ministry of Environment has undertaken a program (1999-2001) to measure levels of contaminants in top marine predators and to develop sensitive biomarkers for the evaluation of toxicological risk in these species. In 1999, 15 swordfishes (Xiphias gladius) taken from the Mediterranean Sea along the Sicilian coast (Strait of Messina, Italy) and in the Atlantic Ocean along the Azores Islands, and analysed for 34 congeners of PCBs and 27 organochlorine (OC) pesticides in gonad, muscle, liver and blubber tissues. In the tissues of Mediterranean swordfishes the sum of the determined PCBs congeners ranged from 4.61 to 4651.17 ng g(-1) on fresh tissue basis. Among organochlorine pesticides DDE, DDT and DDD (TDE) predominated with an overall range of 2.37-4734.56 ng(-1) w.w. In particular p,p'-DDE had concentrations appearing up to 3900 ng(-1), with the highest values found in fatty tissues, such as blubber. In the liver of Azores Island swordfishes lower levels of summation PCBs (8.43-294.17 ng/g w.w.) and summation DDTs (<0.01-217.44 ng/g w.w.) were determined.

Animals↗

PubMed2002

Evidence for recycled Archaean oceanic mantle lithosphere in the Azores plume.

The compositional differences between mid-ocean-ridge and ocean-island basalts place important constraints on the form of mantle convection. Also, it is thought that the scale and nature of heterogeneities within plumes and the degree to which heterogeneous material endures within the mantle might be reflected in spatial variations of basalt composition observed at the Earth's surface. Here we report osmium isotope data on lavas from a transect across the Azores archipelago which vary in a symmetrical pattern across what is thought to be a mantle plume. Many of the lavas from the centre of the plume have lower 187Os/188Os ratios than most ocean-island basalts and some extend to subchondritic 187Os/188Os ratios-lower than any yet reported from ocean-island basalts. These low ratios require derivation from a depleted, harzburgitic mantle, consistent with the low-iron signature of the Azores plume. Rhenium-depletion model ages extend to 2.5 Gyr, and we infer that the osmium isotope signature is unlikely to be derived from Iberian subcontinental lithospheric mantle. Instead, we interpret the osmium isotope signature as having a deep origin and infer that it may be recycled, Archaean oceanic mantle lithosphere that has delaminated from its overlying oceanic crust. If correct, our data provide evidence for deep mantle subduction and storage of oceanic mantle lithosphere during the Archaean era.

Journal Article↗

PubMed2005

Analysis of Y-chromosome variability and its comparison with mtDNA variability reveals different demographic histories between islands in the Azores Archipelago (Portugal).

We determined the Y-chromosomal composition of the population of the Azores Islands (Portugal), by analyzing 20 binary polymorphisms located in the non-recombining portion of the Y-chromosome (NRY), in 185 unrelated individuals from the three groups of islands forming the Archipelago (Eastern, Central and Western). Similar to that described for other Portuguese samples, the most frequent haplogroups were R1(xR1b3f) (55.1%), E(xE3a) (13%) and J (8.6%). Principal components analysis revealed a Western European profile for the Azorean population. No significant differences between Azores and mainland Portugal were observed. However, the haplogroup distribution across the three groups of islands was not similar (P<0.003). The Western group presented differences in the frequencies of haplogroups R1, E(xE3a) and I1b2 (27.3%, 22.7% and 13.6%, respectively) when compared to the other two groups. An assessment of the NRY variability, and its comparison with mitochondrial DNA (mtDNA) variability, was further evidence of the differential composition of males during the settlement of the three groups of islands, contrary to what has been previously deduced for the female settlers using mtDNA data.

Base Sequence↗

PubMed2005

Crystallization and preliminary X-ray analysis of AzoR (azoreductase) from Escherichia coli.

AzoR (azoreductase), an FMN-dependent NADH-azo compound oxidoreductase from Escherichia coli, has been crystallized in the presence of FMN by the sitting-drop vapour-diffusion method using 2-propanol as a precipitant. AzoR catalyzes the reductive cleavage of azo groups. The crystals were found to diffract X-rays to beyond 1.8 A resolution using a synchrotron-radiation source. The crystals belonged to the tetragonal space group P4(2)2(1)2, with unit-cell parameters a = b = 92.2, c = 51.9 A. The crystals are expected to contain one subunit of the homodimer in the asymmetric unit (VM = 2.6 A3 Da(-1)) and to have a solvent content of 51.6%. Data sets were also collected from heavy-atom derivatives for use in phasing. As a result, crystals soaked in a solution containing K2PtCl4 for 23 d were found to be reasonably isomorphous to the native crystals and the presence of Pt atoms could be confirmed. The data sets from the native crystals and the K2PtCl4-derivatized crystals are being evaluated for use in structure determination by single isomorphous replacement with anomalous scattering.

2-Propanol↗

PubMedDate not supplied

Chemical polymorphism of the essential oils from populations of Thymus caespititius grown on the islands Pico, Faial and Graciosa (Azores).

The compositions of the essential oils isolated from the aerial parts of 11 populations of Thymus caespititius collected during the flowering phase on Pico, Faial and Graciosa (Azores) were studied by GC and GC-MS. The monoterpene fraction was dominant in all the oils analysed (55-90%) and consisted mainly of oxygen-containing compounds (44-79%). Sesquiterpenes represented an important fraction of the oils from the populations grown on Graciosa (13-28%). In contrast, this fraction was rather small in the oils from the populations grown on Pico and Faial (6-11%). Despite this, oxygen-containing compounds (4-18%) were always dominant. Cluster analysis of all identified oil components grouped the oils into three main clusters that corresponded with their main components. The oils from the 11 populations studied showed a clear chemical polymorphism that, in some cases, was more evident among populations growing on the same island than among those from different islands.

Azores↗

PubMed2005

Occurrence and characterization of a nucleopolyhedrovirus from Spodoptera littoralis (Lepidoptera: Noctuidae) isolated in the azores.

A nucleopolyhedrovirus (SpliMNPV-Az) was isolated from diseased larvae of Spodoptera littoralis, collected at the Island of S. Miguel in Azores. The virulence of this isolate was tested against S. littoralis larvae in laboratory. LD50 against 2nd and 3rd instars were not significantly different, 1.44x10(4), 3.89x10(4) OBs per larvae, respectively, but both were significantly different from that against 4th instar, which was 61.3x10(4) OBs per larvae. The complete codons sequence of SpliMNPV-Az Polh gene obtained was 750 bp (NCBI GenBank Accession No. AY600451). This sequence was compared to other 38 polyhedrin genes from NPVs and to 6 granulin genes from GVs and resulted to be identical to the sequence of a SpliMNPV previously published, thus indicating that the natural host of SpliMNPV-Az must be S. littoralis. Genetic distances estimated from restriction enzymes profiles showed SpliMNPV-Az is close to the Egyptian SpliMNPV type B, despite some degree of genetic divergence suggested by slight differences observed on PstI profile.

Amino Acid Sequence↗

PubMed2006

Chronic exposure to volcanic environments and cancer incidence in the Azores, Portugal.

Whether volcanic environments pose a risk in cancer incidence is unknown. We investigated this question in two populations, one from an area with active manifestations of volcanism (Furnas) and another from an area without volcanic activity since 3 million years ago (Santa Maria), both in Azores. Incidence data on cancer among the populations of Furnas and Santa Maria during 1991-2001 were obtained from medical records of local health centers. Age-standardized rates and relative risks were estimated. Overall incidence rates were higher in the volcanically active area when observing all cancers and both sexes combined. However, the non-volcanically active area presented higher rates of cancer of digestive, respiratory and intrathoracic organs, mainly in males, while the area with volcanic manifestations showed higher rates of cancer of lip, oral cavity and pharynx, in both sexes, and female breast. Relative risk estimates between both populations suggest a higher risk for cancer in some groups of organs in Furnas, especially of lip, oral cavity and pharynx cancer, and breast, that may be partially explained by the chronic exposure to environmental factors resulting from volcanic activity, such as hazardous gases and aerosols, much of them associated to trace metals.

Age Factors↗

PubMed2003

Composition and antimicrobial activity of the essential oils from invasive species of the Azores, Hedychium gardnerianum and Pittosporum undulatum.

The compositions of the essential oils from the leaves and flowers of Hedychium gardnerianum and from the leaves of Pittosporum undulatum growing on San Miguel Island (Azores) were investigated, and the compounds were identified by GC-MS analyses. The oils in the leaves and flowers of H. gardnerianum were rich in alpha-pinene, beta-pinene and alpha-cadinol, whereas that from P. undulatum was found to contain monoterpenes, sesquiterpenes, diterpenes and alkanes, of which the sesquiterpenes, calamenene (41.4%), farnesol (10.9%), spathulenol (5.6%) and beta-selinene (5.2%) and the diterpene (8beta,13beta)-kaur-16-ene (10.7%) were the major components. Their potential antimicrobial activities were tested against Staphylococcus aureus, S. epidermis and Pseudomonas aeruginosa, and those with the highest activities against S. aureus and S. epidermis were from H. gardnerianum; none had activity against P. aeruginosa. Additionally, the essential oils from Pittosporum undulatum had good antithrombin activity whereas that from H. gardnerianum did not.

Animals↗

PubMed2003

Linkage disequilibrium between S65C HFE mutation and HLA A29-B44 haplotype in Terceira Island, Azores.

Our objective was to investigate the frequency of HFE gene mutations and to study linkage disequilibrium (LD) between HLA-Class I alleles and these mutations in the population of Terceira Island, Azores, Portugal. A total of 218 unrelated individuals were investigated. Three HFE mutations--C282Y, H63D, and S65C--were identified by restriction endonuclease digestion of polymerase chain reaction (PCR)-amplified genomic DNA. HLA-Class I alleles were typed by PCR-single-strand polymorphism. Gene frequencies and LD were estimated using Arlequin V 1.1. Six genotypes were found in the population: WT/WT (58.3%), H63D/WT (31.2%), H63D/H63D (2.3%), H63D/C282Y (0.9%), S65C/WT (4.1%), and C282Y/WT (3.2%). No cases of C282Y or S65C homozygosity were identified. HLA haplotype A3-B7 was in LD with C282Y; HLA alleles A29, B44, and HLA haplotype A29-B44 were in LD with S65C mutation. HFE gene frequencies in this population are similar to those in other European populations; HFE S65C mutation was found in LD with the alleles A29, B44, and with A29-B44 HLA haplotype.

Azores↗

PubMed2000

Antithrombin activity of medicinal plants of the Azores.

A chromogenic bioassay was utilized to determine the antithrombin activity of methylene chloride and methanol extracts prepared from 50 plants of Azores. Extracts of the six plants Hedychium gardneranum, Tropaeolum majus, Gunnera tinctoria, Hedera helix, Festuca jubata and Laurus azorica demonstrated activity of 78% or higher in this bioassay system.

Azores↗

PubMed2001

Natural selection at the MJD locus: phenotypic diversity, survival and fertility among Machado-Joseph Disease patients from the Azores.

Machado-Joseph Disease (MJD) is an autosomal dominant neurodegenerative disorder of adult onset, associated with the expansion of a (CAG)n tract in the coding region of the causative gene, localized on 14q32.1. Machado-Joseph Disease shows non-Mendelian features typical of other triplet repeat disorders, including clinical heterogeneity, variable age at onset and anticipation. Three phenotypes have been proposed (clinical types 1, 2 and 3). Type 1 is associated with early age at onset and a high repeat number of the CAG sequence, and Types 2 and 3 have later onset and lower numbers of CAG repeats. This paper investigates whether there is selection against the MJD gene, acting through differential survival. nuptiality and fertility associated with clinical type and age at onset. The study sample comprised 40 MJD patients from the Azores (Portugal) having fully documented reproductive histories and known dates of death. The proportion of married patients of each clinical type increased from 0.22 among Type 1 patients, to 0.40 in Type 2 and 0.95 in Type 3. Age at onset and length of survival were also associated with marital status, with the married cases having later mean age at onset and longer mean survival time. In the whole sample, clinical type was associated with fertility, with significantly fewer children born to Type 1 patients. Among married patients clinical type was not associated with age at marriage, reproductive span or number of children. No reduction of fertility was detected among married patients in whom the onset of MJD was below the age of 50. The authors' interpretation of these results is that the high-repeat CAG haplotypes associated with early age at onset and clinical Type 1 are selected against through reduced survival and fertility. The fertility component of selection is mediated by nuptiality rather than marital fertility.

Adolescent↗

PubMedDate not supplied

Genetic structure of the Azores: marriage and inbreeding in Flores.

Flores is one of the smallest and most westerly islands of the Atlantic archipelago of the Azores. This preliminary account of the population's demography and genetic structure uses dispensations to contract consanguineous marriages taken from the Roman Catholic marriage registers in order to estimate mean inbreeding rates in the population over the period 1860-1980. Comparisons are made with inbreeding rates on the Portuguese mainland and elsewhere in Western Europe, and reasons suggested to explain the rather high rates of inbreeding encountered on Flores.

Azores↗

PubMed2005

Understanding differences between phylogenetic and pedigree-derived mtDNA mutation rate: a model using families from the Azores Islands (Portugal).

We analyzed the control region of the mitochondrial DNA (mtDNA) from maternally related individuals originating from the Azores Islands (Portugal) in order to estimate the mutation rate of mtDNA and to gain insights into the process by which a new mutation arises and segregates into heteroplasmy. Length and/or point heteroplasmies were found at least in one individual of 72% of the studied families. Eleven new point substitutions were found, all of them in heteroplasmy, from which five appear to be somatic mutations and six can be considered germinal, evidencing the high frequency of somatic mutations in mtDNA in healthy young individuals. Different values of the mutation rate according to different assumptions were estimated. When considering all the germinal mutations, the value of the mutation rate obtained is one of the highest reported so far in family studies. However, when corrected for gender (assuming that the mutations present in men have the same evolutionary weight of somatic mutations because they will inevitably be lost) and for the probability of intraindividual fixation, the value for the mutation rate obtained for HVRI and HVRII (0.2415 mutations/site/Myr) was in the upper end of the values provided by phylogenetic estimations. These results indicate that the discrepancy, that has been reported previously, between the human mtDNA mutation rates observed along evolutionary timescales and the estimations obtained using family pedigrees can be minimized when corrections for gender proportions in newborn individuals and for the probability of intraindividual fixation are introduced. The analyses performed support the hypothesis that (1) in a constant, tight bottleneck genetic drift alone can explain different patterns of heteroplasmy segregation and (2) in neutral conditions, the destiny of a new mutation is strictly related to the initial proportion of the new variant. Another important point arising from the data obtained is that, even in the absence of a paternal contribution of mtDNA, recombination may occur between mtDNA molecules present in an individual, which is only observable if it occurs between mtDNA types that differ at two or more positions.

Azores↗

PubMed2000

Alicyclobacillus hesperidum sp. nov. and a related genomic species from solfataric soils of São Miguel in the Azores.

Several acidophilic, slightly thermophilic or thermophilic Gram-positive isolates were recovered from solfataric soil at Furnas on the Island of São Miguel in the Azores. Phylogenetic analysis of the 16S rRNA gene sequence showed that these organisms represented two novel species of the genus Alicyclobacillus. Strains FR-11T and FR-1b had an optimum growth temperature of about 50 degrees C, whereas strains FR-3 and FR-6T had an optimum growth temperature of about 60 degrees C. Biochemical, physiological and chemotaxonomic characteristics did not distinguish isolates FR-3 and FR-6T from the type strain of Alicyclobacillus acidocaldarius; however, strains FR-11T and FR-1b could be easily distinguished from the type strain of Alicyclobacillus acidoterrestris by the carbon source assimilation pattern and the fatty acid composition. On the basis of the phylogenetic analysis, physiological and biochemical characteristics, and fatty acid composition the name Alicyclobacillus hesperidum is proposed for the species represented by strains FR-11T and FR-1b; a formal name for the new genomic species represented by strains FR-3 and FR-6T is not proposed at this time.

Azores↗

PubMed2004

Sulfurihydrogenibium azorense, sp. nov., a thermophilic hydrogen-oxidizing microaerophile from terrestrial hot springs in the Azores.

Five hydrogen-oxidizing, thermophilic, strictly chemolithoautotrophic, microaerophilic strains, with similar (99-100%) 16S rRNA gene sequences were isolated from terrestrial hot springs at Furnas, São Miguel Island, Azores, Portugal. The strain, designated Az-Fu1T, was characterized. The motile, 0.9-2.0 microm rods were Gram-negative and non-sporulating. The temperature growth range was from 50 to 73 degrees C (optimum at 68 degrees C). The strains grew fastest in 0.1% (w/v) NaCl and at pH 6, although growth was observed from pH 5.5 to 7.0. Az-Fu1T can use elemental sulfur, sulfite, thiosulfate, ferrous iron or hydrogen as electron donors, and oxygen (0.2-9.0%, v/v) as electron acceptor. Az-Fu1T is also able to grow anaerobically, with elemental sulfur, arsenate and ferric iron as electron acceptors. The Az-Fu1T G+C content was 33.6 mol%. Maximum-likelihood analysis of the 16S rRNA phylogeny placed the isolate in a distinct lineage within the Aquificales, closely related to Sulfurihydrogenibium subterraneum (2.0% distant). The 16S rRNA gene of Az-Fu1T is 7.7% different from that of Persephonella marina and 6.8% different from Hydrogenothermus marinus. Based on the phenotypic and phylogenetic characteristics presented here, it is proposed that Az-Fu1T belongs to the recently described genus Sulfurihydrogenibium. It is further proposed that Az-Fu1T represents a new species, Sulfurihydrogenibium azorense.

Azores↗

PubMed2006

Abundance, spatial variance and occupancy: arthropod species distribution in the Azores.

1. The positive abundance-occupancy and abundance-variance relationships are two of the most widely documented patterns in population and community ecology. 2. Recently, a general model has been proposed linking the mean abundance, the spatial variance in abundance, and the occupancy of species. A striking feature of this model is that it consists explicitly of the three variables abundance, variance and occupancy, and no extra parameters are involved. However, little is known about how well the model performs. 3. Here, we show that the abundance-variance-occupancy model fits extremely well to data on the abundance, variance and occupancy of a large number of arthropod species in natural forest patches in the Azores, at three spatial extents, and distinguishing between species of different colonization status. Indeed, virtually all variation about the bivariate abundance-occupancy and abundance-variance relationships is effectively explained by the third missing variable (variance in abundance in the case of the abundance-occupancy relationship, and occupancy in the case of the abundance-variance relationship). 4. Introduced species tend to exhibit lower densities, less spatial variance in these densities, and occupy fewer sites than native and endemic species. None the less, they all lie on the same bivariate abundance-occupancy and abundance-variance, and trivariate abundance-variance-occupancy, relationships. 5. Density, spatial variance in density, and occupancy appear to be all the things one needs to know to describe much of the spatial distribution of species.

Animals↗

PubMed1991

Distribution of Legionella spp. in hydrothermal areas in continental Portugal and the island of São Miguel, Azores.

Nineteen aquatic environment sites from three hydrothermal areas on continental Portugal and one area on the island of São Miguel, Azores, were examined for the recovery of Legionella spp. Physicochemical and bacteriological parameters were also determined for each site. Water temperatures varied between 22 and 67.5 degrees C, although the majority had temperatures above 40 degrees C; the pH varied between 5.5 and 9.2. The number of Legionella spp. recovered varied between 5.0 x 10(2) and 2.3 x 10(6) CFU/liter. A total of 288 isolates from 14 sites were identified by indirect immunofluorescence assay. The majority of the isolates belonged to Legionella pneumophila (74.3%), of which most belong to serogroup 1, but the relative proportion of L. pneumophila serogroups varied considerably. L. pneumophila serogroup 1 constituted 96.2% of the isolates in area 2 from central Portugal, but no isolates of this serogroup were recovered from São Miguel, where serogroup 6 strains were the predominant isolates. Ninety-six percent of the L. pneumophila serogroup 1 isolates belonged to monoclonal antibody subgroups OLDA and Bellingham. Other species identified were L. bozemanii serogroup 2, L. dumoffii, L. micdadei, L. moravica, L. oakridgensis, L. sainticrucis, and L. sainthelensi. Two undescribed species, which react by indirect immunofluorescence assay to antisera to "L. londoniensis" and "L. nautarum" and a group of isolates with strong cross-reaction to L. cincinnatiensis/L. sainticrucis/L. longbeachae by indirect immunofluorescence assay were also recovered. The latter were the only isolates recovered from area 3, in east central Portugal, over a period of 1 year.

Azores↗

PubMed2002

Prevalence of spondyloarthritis in Terceira, Azores: a population based study.

OBJECTIVE: To determine the prevalence of spondyloarthritis (SpA) in the Caucasian population of Terceira Island, Azores. METHODS: Study subjects were recruited from people over the age of 50 years from one half of the island of Terceira (n=24 561). Seventy eight men and 78 women from each five year age group were selected, giving a total of 468 men and 468 women available for study, of whom 490 agreed to take part. These subjects were assessed by dorsal, lumbar, and pelvic radiography. Radiological sacroiliitis was identified in eight patients on whom sacroiliac computed tomography scans were performed. HLA class I typing by polymerase chain reaction with sequence-specific primers was carried out in seven cases. RESULTS: SpA was present in eight subjects (1.6%, 95% CI 0.8 to 2.7%), including seven men (2.7%) and one woman (0.4%). Three (1.2% ) male patients with definite ankylosing spondylitis were HLA-B27 positive. Only one person had a previous diagnosis of SpA. CONCLUSION: These data complement previous studies in European countries on SpA prevalence and establish an estimate of the overall prevalence of SpA in a southern European population.

Adult↗