Publications by authors named "Pedro Brito"

40 Publications

Influence of diagenetic processes and terrestrial/anthropogenic sources in the REE contents of the Cascais submarine canyon (Iberian western coast).

Sci Total Environ 2021 Feb 3;773:145539. Epub 2021 Feb 3.

NIOZ, Royal Netherlands Institute for Sea Research, Department of Ocean Systems, 1790 AB Den Burg, the Netherlands.

Temporal variations of rare earth elements (REE) and their fractionation patterns, major elements, Pb and Hg were determined in two multicores collected at 445 and 2100 m water depth (mwd) in the Cascais submarine canyon (CSC). The PAAS-normalized REE patterns suggest mixing of Tagus estuarine and marine sediments, marked by MREE (Nd-Dy series) enrichment and by positive Eu-anomaly, with marine sediments. The positive Eu/Eu* implies incorporation of detrital feldspar minerals derived from the estuary. Ce/Ce*, (La/Yb) and (Nd/Yb) show differences between the two cores. Core 252-35 from the shallower site is enriched in HREE (Ho-Lu series) over LREE (La-Pr series), a pattern also found in the Tagus estuary in the vicinity of an abandoned chemical complex, where the environment is affected by the legacy of massive-sulfide ores processing. There seems to be only limited down-canyon sediment transport to the deeper reaches where core 252-32 was collected. This deeper site shows Ce/Ce* peaks coinciding with low (La/Yb) values suggesting preferential diagenetic remobilization of LREE relative to HREE. Upcore Pb/Al and Hg/C trends observed in both cores indicate dispersion of the anthropogenic component from the estuary through the CSC, which is less obvious from the ∑REE/Al trends particularly in the deeper site. This may suggest the influence of diagenetic processes in the REE signal, associated with relatively low sediment accumulation rates.
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http://dx.doi.org/10.1016/j.scitotenv.2021.145539DOI Listing
February 2021

Effects of salt marsh plants on mobility and bioavailability of REE in estuarine sediments.

Sci Total Environ 2021 Mar 9;759:144314. Epub 2020 Dec 9.

FCUL-Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal.

Sediments colonised by three halophyte species, Spartina maritima (Curtis) Fernald, Halimione portulacoides (L.) Aellen and Sarcocornia fruticosa (L.) Scott) and bulk sediment from a SW European salt marsh (Tagus estuary, Portugal) were subjected to sequential extractions and analysed to assess the rare earth elements (REE) geochemical fractionation and to evaluate the plants' role in the mobility and bioavailability of these elements. The results showed that REE were mainly bound to the residual (yttrium and heavy-REE) and carbonate (middle-REE and heavy-REE) fractions, followed by the reducible and oxidisable (light-REE and middle-REE) fractions, while the easily soluble fraction was negligible. This fractionation evidenced a sediment REE mobility mainly dependent not only on carbonates but also on FeMn oxyhydroxides and on organic matter content. On the other hand, REE associated with the reducible and oxidisable fractions, and particularly the redox-sensitive Ce, may become more available, due to the redox condition seasonal changes that occur in salt marshes' sediments promoted by the plants' activity. Moreover, this study demonstrated that the REE bioavailability depends not only on the sediments' characteristics and the plants' seasonal activity but also on the specificity of each element, as demonstrated by the different fractionation patterns observed in the various sedimentary fractions.
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http://dx.doi.org/10.1016/j.scitotenv.2020.144314DOI Listing
March 2021

Cerium uptake, translocation and toxicity in the salt marsh halophyte Halimione portulacoides (L.), Aellen.

Chemosphere 2021 Mar 18;266:128973. Epub 2020 Nov 18.

MARE-FCUL, Centro de Ciências Do Mar e Do Ambiente, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016, Lisboa, Portugal.

Halimione portulacoides plants were exposed to dissolved cerium (Ce) in a hydroponic medium for five days. Ce accumulation in plants followed the metal's increase in the medium although with a very low translocation factor (TF < 0.01) between roots and shoots. Ce median concentrations in roots were 586, 988 and 1103 μg/g (dry wt.), while in shoots the median values reached 1.9, 3.5 and 10.0 μg/g (dry wt.), for plants exposed to 300, 600 and 1200 μg/L of Ce, respectively. No significant differences occurred in the length of roots and shoots among treatment groups, albeit plants exposed to the highest Ce concentration showed a clear loss of turgor pressure on the fifth day. An increase of hydrogen peroxide and malondialdehyde levels were observed in the plant shoots at 1200 μg/L of Ce. The highest concentration also triggered an answer by the shoots' antioxidant enzymes with a decrease in the activity of superoxide dismutase and an increase in peroxidase. However, no significant change in catalase activity was observed, compared to the control group, which may indicate that peroxidase played a more crucial role against the oxidative stress than catalase. Combined results indicate that H. portulacoides was actively responding to a toxic effect imposed by this higher Ce concentration. Nevertheless, changes in normal environmental conditions, may increase the bioavailability of Ce, while in areas where acid mine drainage may occur, the highest Ce concentration tested in this study may be largely exceeded, placing the sustainability of halophytes and estuarine marshes at risk.
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http://dx.doi.org/10.1016/j.chemosphere.2020.128973DOI Listing
March 2021

Warming enhances lanthanum accumulation and toxicity promoting cellular damage in glass eels (Anguilla anguilla).

Environ Res 2020 12 17;191:110051. Epub 2020 Aug 17.

MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016, Lisboa, Portugal.

Cumulative and continuing human emissions of greenhouse gases to the atmosphere are causing ocean warming. Rising temperature is a major threat to aquatic organisms and may affect physiological responses, such as acid-base balance, often compromising species fitness and survival. It is also expected that warming may influence the availability and toxicological effects of pollutants, including Rare Earth Elements. These are contaminants of environmental emerging concern with great economic interest. This group comprises yttrium, scandium and lanthanides, being Lanthanum (La) one of the most common. The European eel (Anguilla anguilla) is critically endangered and constitutes a delicacy in South East Asia and Europe, being subject to an increasing demand on a global scale. Considering the vulnerability of early life stages to contaminants, we exposed glass eels to 1.5 μg L of La for five days, plus five days of depuration, under a present-day temperature and warming scenarios (△T = +4 °C). The aim of this study was to assess the bioaccumulation, elimination and specific biochemical enzymatic endpoints in glass eels (Anguilla anguilla) tissues, under warming and La. Overall, our results showed that the accumulation and toxicity of La were enhanced with increasing temperature. The accumulation was higher in the viscera, followed by the head, and ultimately the body. Elimination was less effective under warming. Exposure to La did not impact acetylcholinesterase activity. Moreover, lipid peroxidation peaked after five days under the combined exposure of La and warming. The expression of heat shock proteins was majorly suppressed in glass eels exposed to La, at both tested temperatures. This result suggests that, when exposed to La, glass eels were unable to efficiently prevent cellular damage, with a particularly dramatic setup in a near-future scenario. Further studies are needed towards a better understanding of the effects of lanthanum in a changing world.
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http://dx.doi.org/10.1016/j.envres.2020.110051DOI Listing
December 2020

The effects of field-realistic doses of imidacloprid on Melipona quadrifasciata (Apidae: Meliponini) workers.

Environ Sci Pollut Res Int 2020 Nov 5;27(31):38654-38661. Epub 2020 Jul 5.

Laboratório de Biologia Reprodutiva de Plantas, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil.

The presence of Brazilian native bees can improve tomato production by increasing pollination effectiveness. However, the extensive use of pesticides in tomato cultures may be harmful to bees. Imidacloprid-based insecticides are used in tomato plantations because of its high efficiency against tomato pests. This study investigated the effects of oral intake of field-realistic concentrations of imidacloprid by M. quadrifasciata workers, a stingless native bee from Brazil and effective pollinators of tomato crops. The oral intake of sucrose syrup added with 10, 35, or 70 ppb of imidacloprid did not increase the mortality rate when compared with the control group. However, we observed a reduction in the workers' motility and food consumption. We also treated M. quadrifasciata workers with sucrose syrup mixed with an imidacloprid-based insecticide (Evidence 700 WG®, Bayer), with the final concentration of 250 ppb of imidacloprid. This treatment did not cause visible alterations of the intestine absorptive cells of the bees' midgut and did not increase DNA damage. Therefore, the observed reduction of food consumption and locomotion behavior of M. quadrifasciata workers may contribute to the global effort to understand the contribution of neonicotinoids on bees' population decline process.
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http://dx.doi.org/10.1007/s11356-020-08530-9DOI Listing
November 2020

Percutaneous Transseptal Bioprosthetic Implantation in Failed Prosthetic Surgical Mitral Valve - Brazilian Multicenter Experience.

Arq Bras Cardiol 2020 09;115(3):515-524

Universidade de São Paulo Faculdade de Medicina Hospital das Clínicas Instituto do Coração - Hemodinâmica, São Paulo, SP - Brasil.

Background: Percutaneous intervention in patients with bioprosthetic mitral valve dysfunction is an alternative to conventional surgical treatment.

Objectives: To report the first Brazilian experience with transseptal transcatheter bioprosthetic mitral valve-in-valve implantation (transseptal-TMVIV).

Methods: Patients with surgical bioprosthetic dysfunction submitted to transseptal-TMVIV in 12 Brazilian hospitals were included. The significance level adopted was p<0.05.

Results: From June/2016 to February/2019, 17 patients underwent transseptal-TMVIV. Their median age was 77 years (IQR,70-82) and median Society of Thoracic Surgeons predicted risk of mortality (STS-PROM) score was 8.7% (IQR,7.2-17.8). All patients had limiting symptoms of heart failure (FC≥III) and 5 (29.4%) had undergone more than one previous thoracotomy. Transseptal-TMVIV was successful in all patients. Echocardiographic assessment showed a significant reduction in mean mitral valve gradient (pre-intervention, 12±3.8 mmHg; post-intervention, 5.3±2.6 mmHg; p<0.001), in addition to an increase in mitral valve area (pre-intervention, 1.06±0.59 cm2; post-intervention, 2.18±0.36 cm2; p<0.001) sustained for 30 days. There was a significant and immediate reduction in the pulmonary artery systolic pressure, with an additional reduction in 30 days (pre-intervention, 68.9±16.4 mmHg; post-intervention, 57.7±16.5 mmHg; 30 days, 50.9±18.7 mmHg; p<0.001). During follow-up (median, 162 days; IQR, 102-411), significant clinical improvement (FC≤II) was observed in 87.5% of the patients. One patient (5.9%) had left ventricular outflow tract (LVOT) obstruction and died right after the procedure, and another died at 161 days of follow-up.

Conclusion: The first Brazilian experience with transseptal-TMVIV shows the safety and effectivity of the new technique. The LVOT obstruction is a potentially fatal complication, reinforcing the importance of patients' selection and of procedural planning. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0).
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http://dx.doi.org/10.36660/abc.20190252DOI Listing
September 2020

Neonatal exposure to aluminum chloride disrupts branching morphogenesis and hormonal signaling of the ventral male prostate and female prostate of gerbils.

J Trace Elem Med Biol 2020 May 20;61:126559. Epub 2020 May 20.

Laboratory of Microscopy Applied to Reproduction, Department of Histology, Embryology and Cell Biology, Institute of Biological Sciences, Federal University of Goiás, Goiania, Goias 74001970, Brazil. Electronic address:

Backgroung: Exposure to environmental pollutants in critical developmental windows may predispose the prostate to permanent changes in its homeostasis. Thus, it is essential to know the effects that environmental toxics, such as aluminum, can cause during the development of this gland. The aim of this study was to evaluate the effects of neonatal aluminum exposure on the ventral male prostate and the female prostate of 15 days old gerbils.

Methods: Male and female gerbils were exposed orally to 10 mg/kg/day of aluminum chloride from the 1st to the 14th postnatal day life. At 15 days of life, gerbils were euthanized and their prostates were collected for biometric, morphological, morphometric, immunohistochemical and three-dimensional reconstruction analyzes.

Results: Al exposure caused a reduction in body weight in males and a significant increase in serum testosterone levels in females. Prostate branching morphogenesis was intensified in males, who had greater length, number and area of prostatic epithelial buds. Additionally, Al altered the prostate hormonal regulation of males and females, causing up regulation of the androgen receptor and estrogen receptor alpha in the female prostate, and increased immunostaining of the androgen receptor in the ventral male prostate. These changes were associated with an increased rate of epithelial and stromal cell proliferation in both sexes.

Conclusion: Together, these results indicate that Al altered the neonatal development of the prostate and that this metal acted as an endocrine disruptor in this gland.
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http://dx.doi.org/10.1016/j.jtemb.2020.126559DOI Listing
May 2020

ASSOCIATION OF SERUM VASOGENIC AND PROINFLAMMATORY FACTORS WITH CLINICAL RESPONSE TO ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR FOR DIABETIC MACULAR EDEMA.

Retina 2021 Feb;41(2):345-354

Department of Ophthalmology, Centro Hospitalar e Universitario de Coimbra (CHUC), Coimbra, Portugal.

Purpose: To study the role of serum biomarkers as prognostic factors for qualitative and quantitative response to anti-vascular endothelial growth factor injections for diabetic macular edema (DME).

Methods: Sixty-seven eyes with DME were treated with intravitreal bevacizumab during a 12-month follow-up period. All cases underwent a baseline workup consisting of 12 inflammatory, metabolic and prothrombotic factors. The following outcomes were evaluated at 3-month intervals until 1 year of follow-up: visual acuity, central subfield thickness (CST), macular volume (MV), % of change from baseline in CST, occurrence of a CST change < 10%, a CST change >20%, and a CST <330 µm, achieving an improvement ≥2 lines of visual acuity, achieving visual acuity ≥20/40.

Results: A significant improvement in CST and visual acuity was seen from third month onwards. Twenty-eight (48.1%) cases were classified as "early responders," 24 (35.8%) as "late responders", and 15 (22.4%) as "poor responders." Serum vascular endothelial growth factor-A levels were significantly lower in "poor responders" (P = 0.006). C-reactive protein (hsCRP) was associated with a limited anatomic response (<10% CST change) (P = 0.002, OR = 1.845, cutoff value of hsCRP = 1.84 mg/L). hsCRP was also negatively associated with obtaining a final CST <330 µm (P = 0.04, r2 = 0.112, OR = 0.643). Baseline visual acuity was significantly associated with 12th month visual acuity (P < 0.001, r2 = 0.602) and also with an improvement ≥2 visual acuity lines (P = 0.009, OR = 20.54).

Conclusion: Increased high-sensitivity C-reactive protein was associated with limited anatomic response to anti-vascular endothelial growth factor treatment and persistent DME. Poor responders had significantly lower values of serum vascular endothelial growth factor-A, suggesting an alternative pathogenic pathway for persisting DME.
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http://dx.doi.org/10.1097/IAE.0000000000002852DOI Listing
February 2021

Paternal and maternal mutations in X-STRs: A GHEP-ISFG collaborative study.

Forensic Sci Int Genet 2020 05 5;46:102258. Epub 2020 Feb 5.

Laboratório de Diagnóstico por DNA (LDD), Universidade do Estado do Rio de Janeiro, Brazil.

The GHEP-ISFG organized a collaborative study to estimate mutation rates for the markers included in the Investigator Argus X-12 QS kit Qiagen. A total of 16 laboratories gathered data from 1,612 father/mother/daughter trios, which were used to estimate both maternal and paternal mutation rates, when pooled together with other already published data. Data on fathers and mothers' age at the time of birth of the daughter were also available for ∼93 % of the cases. Population analyses were computed considering the genetic information of a subset of 1,327 unrelated daughters, corresponding to 2,654 haplotypes from residents in several regions of five countries: Argentina, Brazil, Ecuador, Portugal and Spain. Genetic differentiation analyses between the population samples from the same country did not reveal signs of significant stratification, although results from Hardy-Weinberg and linkage disequilibrium tests indicated the need of larger studies for Ecuador and Brazilian populations. The high genetic diversity of the markers resulted in a large number of haplotype combinations, showing the need of huge databases for reliable estimates of their frequencies. It should also be noted the high number of new alleles found, many of them not included in the allelic ladders provided with the kit, as very diverse populations were analyzed. The overall estimates for locus specific average mutation rates varied between 7.5E-04 (for DXS7423) and 1.1E-02 (for DXS10135), the latter being a troublesome figure for kinship analyses. Most of the found mutations (∼92 %) are compatible with the gain or loss of a single repeat. Paternal mutation rates showed to be 5.2 times higher than maternal ones. We also found that older fathers were more prone to transmit mutated alleles, having this trend not been observed in the case of the mothers.
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http://dx.doi.org/10.1016/j.fsigen.2020.102258DOI Listing
May 2020

Serum pro-inflammatory factors as predictors of persistent diabetic macular oedema with limited anatomic response to anti-VEGF: association with intravitreal injection treatment profiles in real-world setting.

Acta Ophthalmol 2020 Jun 19;98(4):e421-e427. Epub 2019 Nov 19.

Department of Ophthalmology, Centro Hospitalar e Universitario de Coimbra (CHUC), Coimbra, Portugal.

Purpose: To study the role of serum levels of pro-inflammatory factors in the identification of persistent diabetic macular oedema (DME) cases with limited anatomic response to anti-VEGF. Additionally, possible predictive associations between serum factors and intravitreal treatment profiles were analysed.

Methods: Cases with DME were treated with monthly bevacizumab (BVZ). After the sixth month of follow-up, if the change in central foveal thickness (CFT) was <20% of baseline, combination treatment with triamcinolone was initiated. All cases underwent a baseline laboratory workup including inflammatory, metabolic and prothrombotic factors. The following outcome parameters were evaluated: percentage of CFT change from baseline, occurrence of persistent DME with <20% change in CFT, achieving CFT <330 μm with ≤6 BVZ injections, total number of intravitreal injections (IVI), number of IVI after the 6th month and number of triamcinolone acetonide (TCA) injections.

Results: A total of 58 cases were included receiving a mean of 7.23 ± 1.55 IVI in 12 months, resulting in a significant improvement of visual acuity (VA) and CFT. No significant differences were found for baseline CFT, baseline LogMAR VA, diabetic retinopathy grade, age or duration of DM2 between cases initiating TCA and those treated only with anti-VEGF. Significant correlations were found between total number of IVI and the following serum factors: high-sensitivity C-reactive protein (hsCRP) (p = 0.004, r = 0.395), creatinine (p = 0.023, r = 0.338) and homocysteine (p = 0.037, r = 0.309). Regression analysis revealed that hsCRP was a significant predictor of TCA treatment (p = 0.028, r  = 0.350). Cases requiring ≤6 IVI had significantly lower values of hsCRP (1.33 ± 1.07 versus 2.46 ± 2.18 mg/l, p = 0.016) and creatinine (0.71 ± 0.28 versus 0.94 ± 0.19 mg/dl, p = 0.003).

Conclusions: Serum markers of microvascular damage (hsCRP, homocysteine and creatinine) were associated with a higher frequency of IVI due to persistent DME, suggesting a role for such biomarkers in the identification of limited responders to anti-VEGF monotherapy.
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http://dx.doi.org/10.1111/aos.14308DOI Listing
June 2020

Impacts of phytoplankton blooms on trace metal recycling and bioavailability during dredging events in the Sado estuary (Portugal).

Mar Environ Res 2019 Nov 6:104837. Epub 2019 Nov 6.

Marine and Environmental Sciences Centre (MARE), Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016, Lisboa, Portugal.

This work evaluates the impact of phytoplankton blooms on metal availability driven by dredging, in an area of the Sado estuary (Portugal), subject to ongoing dredging operations during the entire sampling period. In situ changes of chlorophyll a concentration, bioavailable trace metals (Cr, Mn, Co, Ni, Cu, Zn, Cd and Pb) in the water column, metal content in particulate matter, and particulate metal to bioavailable metal ratios were investigated during pre-bloom, bloom and post-bloom conditions to evaluate the potential of the phytoplankton-mediated metal removal. Metals in particulate matter significantly enhanced concomitantly with the decline of metals (mostly Mn, Co, Cu, Zn, and Pb) in the water column during the bloom, in comparison with pre- and post-bloom periods. During the peak of the phytoplankton bloom, bioavailable Cr, Mn, Co, Ni, Cu, Zn, Cd and Pb were reduced to 30, 99, 100, 87, 98, 72, 84 and 88% of their original levels (pre-bloom values). Copper and Pb, and to a lesser extent, Zn and Mn, were ranked as more particle reactive. Volume particulate matter concentrations of Mn, Ni, Cu and Pb much higher than the bioavailable concentrations, indicated that phytoplankton is likely to be a dominant sink of these metals during the bloom period. Thus, Mn, Ni, Cu and Pb are prone to be transferred and biomagnified into the marine food web. These results highlight phytoplankton blooms as important biological sinks of trace metals during dredging, which should be taken into consideration in planning and management of dredging, to minimise environmental impacts and protect estuarine and coastal ecosystems.
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http://dx.doi.org/10.1016/j.marenvres.2019.104837DOI Listing
November 2019

Platinum and rhodium in Tagus estuary, SW Europe: sources and spatial distribution.

Environ Monit Assess 2019 Aug 21;191(9):579. Epub 2019 Aug 21.

Division of Oceanography and Marine Environment, IPMA-Portuguese Institute of Sea and Atmosphere, Rua Alfredo Magalhães Ramalho 6, 1495-165, Algés, Portugal.

The spatial distribution of Pt and Rh was assessed in Tagus estuary and their sources discussed. Both elements were analysed in superficial sediment samples (n = 72) by adsorptive cathodic stripping voltammetry. Concentrations varied within the following ranges: 0.18-5.1 ng Pt g and 0.02-1.5 ng Rh g. Four distinct areas were established: "reference"; waste- and pluvial water discharge; motorway bridges and industrialised areas. The calculated reference median concentrations were 0.55 ng Pt g and 0.27 ng Rh g. Linear relationships were found between Pt and Al, Fe and LOI, whereas Rh depicted scattered patterns. The highest concentrations were found nearby industrialised areas and a motorway bridge, corresponding to the enrichment of 10 and 6 times the background of Pt and Rh, respectively. The main sources of contamination to the Tagus estuary derived from historical and present industrial activities and from automotive catalytic converters. Large variations of Pt/Rh ratio (0.48-39) point to different sources, reactivity and dilution effects.
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http://dx.doi.org/10.1007/s10661-019-7738-zDOI Listing
August 2019

Spectral model for diagnosis of acute leukemias in whole blood and plasma through Raman spectroscopy.

J Biomed Opt 2018 10;23(10):1-11

Universidade Anhembi Morumbi-UAM, Center for Innovation, Techonology and Education-CITE, Parque Tecn, Brazil.

Acute leukemias are oncohematological diseases that compromise the bone marrow and have a complex diagnostic definition, leading to a high mortality when diagnosed late. This study proposed to determine the spectral differences between whole blood and plasma samples of healthy and leukemic subjects based on Raman spectroscopy (RS), correlating these differences with their resulting biochemical alterations and performing discriminant analysis of the samples (n  =  38 whole blood and n  =  40 plasma samples). Raman spectra were obtained using a dispersive Raman spectrometer (830-nm wavelength, 280-mW laser power, 30-s exposure time) with a Raman probe. The exploratory analysis based on principal component analysis (PCA) of the blood and plasma sample's spectra showed loading vectors with peaks related to amino acids, proteins, carbohydrates, lipids, and carotenoids, being the spectral differences related to amino acids and proteins for whole blood samples, and mainly carotenoids for plasma samples. Discriminant models based on partial least squares (PLS) and PCA were developed and classified the spectra as healthy or leukemic, with sensitivity of 91.9% (PLS) and 83.9% (PCA), specificity of 100% (both PLS and PCA), and overall accuracy of 96.5% (PLS) and 93.0% (PCA) for the whole blood spectra. In plasma, the sensitivity was 95.7% (PLS) and 11.6% (PCA), specificity of 98% (PLS) and 100% (PCA), and overall accuracy of 97.1% (PLS) and 64.1% (PCA). The study demonstrated that RS is a technique with potential to be applied in the diagnosis of acute leukemias in whole blood samples.
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http://dx.doi.org/10.1117/1.JBO.23.10.107002DOI Listing
October 2018

Yttrium and rare earth elements fractionation in salt marsh halophyte plants.

Sci Total Environ 2018 Dec 4;643:1117-1126. Epub 2018 Jul 4.

IPMA - Instituto Português do Mar e da Atmosfera, Rua Alfredo Magalhães Ramalho, 6, 1495-006 Lisboa, Portugal.

Salt marshes act as natural deposits of different metals (e.g. heavy-metals), while halophyte plants are known to retain and accumulate them in the different tissues. Scarce data exists on accumulation, partition and fractionation of YREE in these plants. To study the relationship between halophyte plants and YREE, contents of these metals were determined by ICP-MS in sediment, and in the different plants organs, from Rosário's salt marsh, in Tagus estuary (SW Europe). Results show significant differences (p < 0.001) in YREE contents between sediments. In non-colonised sediment Y was lower (5.0-18 mg·kg) compared to the Sarcocornia fruticosa and Spartina maritima sediment cores (19-26 and 20-26 mg·kg, respectively). The same was observed for ΣREE, with lower values in non-colonised sediment (32-138 mg·kg), while colonised ones presented higher contents (146-174 and 151-190 mg·kg, for S. fruticosa and S. maritima, respectively). These significant differences (p < 0.05) are explained by the sediments' nature. Yttrium and ΣREE Al-normalised ratios in non-colonised sediment ranged from 1.5 to 2.3 and 11 to 13, respectively. The colonised sediments revealed significant higher ratios (particularly for ΣREE/Al ratios; p < 0.001), varying from Y/Al: 1.8-2.3 and ΣREE: 13-16 for S. fruticosa, and Y/Al: 1.4-2.3 and ΣREE: 12-18, for S. maritima. Results suggest that these plants may promote YREE enrichment in the sediments. No differences in fractionation patterns among sediments and in both species roots were found, but fractionation was different from those in the sediment, with similar middle-REE (MREE) enrichment and no light-REE (LREE) and heavy-REE (HREE) fractionation. No evidence of YREE transfer to aboveground organs was observed. Different fractionation patterns in stems and leaves were registered, with clear enrichment of LREE relative to HREE and an increase in the MREE enrichment. Therefore, these plants showed low ability to accumulate and translocate YREE but may promote its enrichment in the sediments.
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http://dx.doi.org/10.1016/j.scitotenv.2018.06.291DOI Listing
December 2018

Serological inflammatory factors as biomarkers for anatomic response in diabetic macular edema treated with anti-VEGF.

J Diabetes Complications 2018 Jul 11;32(7):643-649. Epub 2018 May 11.

Department of Ophthalmology, Centro Hospitalar e Universitario de Coimbra (CHUC), Portugal; Faculty of Medicine, Institute for Biomedical Imaging and Life Sciences (FMUC-IBILI), University of Coimbra, Coimbra, Portugal; Association for Innovation and Biomedical Research on Light and Image (AIBILI), Coimbra, Portugal.

Purpose: To study the relationship between systemic pro-inflammatory factors and macular structural response to intravitreal bevacizumab for diabetic macular edema (DME).

Methods: Prospective study including 30 cases with DME, treated with bevacizumab and a minimum follow-up of 6 months. All cases underwent baseline laboratory testing for cardiovascular risk (high sensitivity C-reactive protein (hsCRP), homocystein), dyslipidemia, renal dysfunction and glucose control. Serum levels of VEGF, soluble ICAM-1, MCP-1 and TNF-α were assessed by enzyme-linked immunosorbent assay kits. Significant associations between systemic factors and quantitative and qualitative spectral-domain optical coherence macular features were analyzed.

Results: A mean of 4.82 ± 0.56 intravitreal injections was performed, resulting in significant improvement of central foveal thickness (CFT) (p < 0.001). A significant association with third month CFT decrease <10% was found for hsCRP (3.33 ± 2.01 vs 1.39 ± 1.15 mg/l, p = 0.007) and ICAM1 (975.54 ± 265.49 vs 727.07 ± 336.09 pg/ml, p = 0.012). ROC curve analysis indicated hsCRP and ICAM1 as significant biomarkers for 3rd month reduced anatomic response (area under the curve (AUC) = 0.807, p = 0.009 for hsCRP; AUC = 0.788, p = 0.014 for ICAM1). ROC curve analysis revealed hsCRP as a significant biomarker for 6th month CFT decrease <10% (AUC = 0.903, p < 0.001, cutoff value = 1.81 mg/l). A significant association with 6th month CFT decrease ≥25% was found for serum MCP1 (244.69 ± 49.34 pg/ml vs 319.24 ± 94.88 pg/ml, p = 0.017) and serum VEGF (90.84 ± 37.33 vs 58.28 ± 25.19 pg/ml, p = 0.027). The combined model of serum VEGF and LDL-cholesterol was found to be predictive of 6th month hard exudate severity (p = 0.001, r2 = 0.463).

Conclusions: Increased levels of hsCRP and ICAM1 were found to be significant biomarkers for early reduced anatomic response to anti-VEGF treatment. Cases with higher serum levels of such factors had increased CFT values, despite treatment, suggesting inner blood-retinal barrier breakdown that is not adequately responsive to anti-VEGF monotherapy.
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http://dx.doi.org/10.1016/j.jdiacomp.2018.05.006DOI Listing
July 2018

Accumulation, elimination and neuro-oxidative damage under lanthanum exposure in glass eels (Anguilla anguilla).

Chemosphere 2018 Sep 7;206:414-423. Epub 2018 May 7.

IPMA, Portuguese Institute of Sea and Atmosphere, Rua Alfredo Magalhães Ramalho, 6, 1495-006 Lisbon, Portugal; CIIMAR, Marine and Environmental Research Center, Rua dos Bragas, 289, 4050-123 Porto, Portugal.

Rare earth elements (REEs) comprise elements from lanthanum to lutetium that together with yttrium and scandium are emergent contaminants of critical importance for numerous groundbreaking environmental technologies. Transfer to aquatic ecosystems is expected to increase, however, little information is known about their potential impacts in marine biota. Considering the endangered conservation status of the European eel (Anguilla anguilla) and the vulnerability of early fish life stages to contaminants, we exposed glass eels, through water, to an environmentally relevant concentration (120 ng.L) of lanthanum (La) for 7 days (plus 7 days of depuration). The aim was to study the accumulation and elimination of La in eel's body and subsequent quantification of acetylcholinesterase (AchE), lipid peroxidation and antioxidant enzymatic machinery. Accumulation peaked after 72 h-exposure to La, decreasing afterwards, even in continuous exposure. Accumulation was higher in the viscera, followed by the skinless body and ultimately in the head, possibly as a protective mechanism to cope with La neurotoxicity. A significant increase in AChE activity was observed in La-exposed glass eels, suggesting that La may inhibit the binding of acetylcholine. A depression in lipid peroxidation was registered under La exposure, possibly indicating that La may play physiological activities and functions as a free radical scavenger. Catalase activity was significantly inhibited in La-exposed glass eels after 72 h, indicating that the availability of La may induce physiological impairment. The quantification of Glutathione S-Transferase activity revealed no differences between control and La-exposed organisms. Further investigation is needed towards understanding the biological effects of REEs.
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http://dx.doi.org/10.1016/j.chemosphere.2018.05.029DOI Listing
September 2018

Clinical Reasoning: Monocular vision loss, ophthalmoplegia, and strokes in a 61-year-old man with diabetes mellitus.

Neurology 2017 12;89(24):e276-e281

From the Departments of Neurology (G.L., Z.F., W.D.Z., D.M.) and Pathology (S.H., P.d.B.), Medstar Georgetown University Hospital, Washington, DC.

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http://dx.doi.org/10.1212/WNL.0000000000004742DOI Listing
December 2017

Sources and distribution of yttrium and rare earth elements in surface sediments from Tagus estuary, Portugal.

Sci Total Environ 2018 Apr 27;621:317-325. Epub 2017 Nov 27.

IPMA - Portuguese Institute of Sea and Atmosphere, Rua Alfredo Magalhães Ramalho, 6, 1495-006 Lisbon, Portugal.

The distribution and sources of yttrium and rare-earth elements (YREE) in surface sediments were studied on 78 samples collected in the Tagus estuary (SW Portugal, SW Europe). Yttrium and total REE contents ranged from 2.4 to 32mg·kg and 18 to 210mg·kg, respectively, and exhibited significant correlations with sediment grain-size, Al, Fe, Mg and Mn, suggesting a preferential association to fine-grained material (e.g. aluminosilicates but also Al hydroxides and Fe oxyhydroxides). The PAAS (Post-Archean Australian Shale) normalized patterns display three distinct YREE fractionation pattern groups along the Tagus estuary: a first group, characterized by medium to coarse-grained material, a depleted and almost flat PAAS-normalized pattern, with a positive anomaly of Eu, representing one of the lithogenic components; a second group, characterized mainly by fine-grained sediment, with higher shale-normalized ratios and an enrichment of LREE relative to HREE, associated with waste water treatment plant (WWTP) outfalls, located in the northern margin; and, a third group, of fine-grained material, marked by a significant enrichment of Y, a depletion of Ce and an enrichment of HREE over LREE, located near an inactive chemical-industrial complex (e.g. pyrite roast plant, chemical and phosphorous fertilizer industries), in the southern margin. The data allow the quantification of the YREE contents and its spatial distribution in the surface sediments of the Tagus estuary, identifying the main potential sources and confirming the use of rare earth elements as tracers of anthropogenic activities in highly hydrodynamic estuaries.
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http://dx.doi.org/10.1016/j.scitotenv.2017.11.245DOI Listing
April 2018

Insights of Pb isotopic signature into the historical evolution and sources of Pb contamination in a sediment core of the southwestern Iberian Atlantic shelf.

Sci Total Environ 2017 May 14;586:473-484. Epub 2017 Feb 14.

IPMA, Portuguese Institute of Sea and Atmosphere, Rua Alfredo Magalhães Ramalho, 6, 1449-006 Lisboa, Portugal; CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal.

Stable Pb isotopic ratios and concentrations of Al, Cu and Pb were measured in a 5m long sediment core (VC2B) retrieved at 96m water depth in the southwestern Iberian Atlantic shelf. Five phases during the last 9.5kyrs were identified, two of them (Roman Period and modern mining) marked by a decrease of Pb/Pb ratios reflecting additional inputs of Pb derived from mining activities. The Roman Period was also characterized by high Pb/Pb ratios suggesting the exploitation of the outcropping portion of the orebody intensely weathered when compared with the other formations later mined. The shift of Pb/Pb ratios towards linearity took approximately 1.0kyrs, which may mirror the time of environmental recovery from the impact of Roman mining activities. The application of a mixing model allowed the quantification of the contribution associated with anthropogenic mining activities to the shelf sediments. The maximum values of Pb contamination occurred in the 20 century. This study gives direct evidence of Pb and Cu exploitation over the last 2000years. The stable Pb isotopic signatures point to legacy of mining activities that are still the prevailing metal source recorded in the southwestern Iberian Atlantic shelf sediments.
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http://dx.doi.org/10.1016/j.scitotenv.2017.01.204DOI Listing
May 2017

Endocrine-disrupting effects of methylparaben on the adult gerbil prostate.

Environ Toxicol 2017 Jun 9;32(6):1801-1812. Epub 2017 Feb 9.

Department of Histology, Embryology and Cell Biology, Laboratory of Histophysiology, Institute of Biological Sciences, Federal University of Goiás, Goiânia, Goiás, 74001970, Brazil.

Parabens are xenoestrogens widely employed in cosmetics, foodstuffs, and pharmaceutical products. These chemicals are known to disrupt hormone-dependent organs, due to their binding affinity for hormonal receptors. Although recent studies have evaluated the endocrine-disrupting potential of parabens in several reproductive organs, few have investigated the effects of these chemicals in the prostate. The aim of this work was to evaluate the effects of oral exposure to methylparaben (500 mg/kg/day) for 3, 7, and 21 days on male and female adult gerbil prostate. For this purpose, we employed biometrical, morphological, and immunohistochemical analyses. The results showed that methylparaben caused morphological changes in gerbil prostates in all experimental groups. These animals displayed similar alterations such as prostate epithelial hyperplasia, increased cell proliferation, and a higher frequency of AR-positive cells. However, the prostate of the female gerbil showed additional changes such as stromal inflammatory infiltration, intraepithelial neoplasia foci, and an increase in AR-positive frequency. Altogether, these data show that methylparaben was responsible for disrupting estrogenic and androgenic receptors, suggesting that parabens may have estrogenic and antiandrogenic effects in the prostate.
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http://dx.doi.org/10.1002/tox.22403DOI Listing
June 2017

Footprint of roman and modern mining activities in a sediment core from the southwestern Iberian Atlantic shelf.

Sci Total Environ 2016 Nov 29;571:1211-21. Epub 2016 Jul 29.

IPMA, Portuguese Institute of Sea and Atmosphere, Division of Environmental Oceanography and Bioprospection, Rua Alfredo Magalhães Ramalho, 6, 1449-006 Lisboa, Portugal; CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal.

A 5-m long sediment core (VC2B), retrieved in the Southwestern Iberian Atlantic shelf, at 96m water depth, was used to assess major changes in climate and human activities during the last 9.7kyrs. Analytical measurements included sedimentological (mean grain size, and the contents of sand, silt and clay), geochemical (major, minor, trace and rare earth elements; REEs) and chronological ((210)Pb and (14)C) parameters. Two episodes of increment of fine-grained particles, occurring at 3050BCE and 1350CE, suggest the retreat of the coast line to the present level and the beginning of a wetter phase associated with the "Little Ice Age". The North American Shale Composite (NASC)-normalized REE-pattern detected in the shelf is similar to that found in the Guadiana estuarine sediments. The possibility of this estuary as a contributor to the sediment load deposited in the adjacent coastal zone was indicated. Trace elements were significantly correlated with Al until 1850CE, pointing that grain-size rules its distribution in sediments. The depth variation of As, Cu and Pb enrichment factors relative to background values shows two periods of intense human activity that can be mainly linked to mining: (i) across the Roman Period, marked by low enrichments; and (ii) starting on the second half of the 19th century until nowadays with significantly increased enrichments, especially of Pb and Cu. In addition to As, Cu and Pb, this period is also marked by high enrichments of Hg and Zn. Despite the decrease/closure of sulphide massive deposits mining exploitation (e.g., São Domingos, Las Herrerias) during the second half of the 20th century, results showed ongoing input of Pb, Cu, As, Hg and Zn to coastal sediments. Thus, the legacy of contamination by these elements, mainly from leaching of slags and tailings, and remobilization/reworking of contaminated estuarine sediments, is still recorded in marine sediments.
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http://dx.doi.org/10.1016/j.scitotenv.2016.07.143DOI Listing
November 2016

Bowel perforation associated with robust response to BRAF/MEK inhibitor therapy for -mutant melanoma: a case report.

Melanoma Manag 2015 May 18;2(2):115-120. Epub 2015 May 18.

Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Washington, DC 20057, USA.

Combination BRAF/MEK inhibition has shown improved response rates and longer progression-free and overall survival for patients with -mutant metastatic melanoma. A 63-year-old female with widely metastatic V600E-mutant melanoma was treated with dabrafenib/trametinib. Ten weeks into therapy, she was treated conservatively for a partial bowel obstruction involving a lesion in the distal ileum. She presented two weeks later with CT evidence of a high-grade bowel obstruction with perforation. Emergent surgery was performed. Intraoperative inspection and pathologic analysis of the resected specimen revealed no evidence of melanoma. Seven months postoperatively she is disease free and fully functional. Rapid BRAF/MEK inhibitor-induced regression of small bowel lesions can result in bowel perforation, which is critical to distinguish from the consequences of disease progression.
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http://dx.doi.org/10.2217/mmt.15.10DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6094601PMC
May 2015

Light-distortion analysis as a possible indicator of visual quality after refractive lens exchange with diffractive multifocal intraocular lenses.

J Cataract Refract Surg 2015 Mar 21;41(3):613-22. Epub 2015 Feb 21.

From the Clínica Oftalmológica das Antas (Brito, Monteiro, Salgado-Borges), the Clinsborges Clínica Oftalmológica (Salgado-Borges), Porto, the Ophthalmology Department, Hospital Privado da Trofa (Brito), Trofa, and the Physics Department (Neves, Meijome), Universidade do Minho, Braga, Portugal.

Purpose: To study the perception of light distortion after refractive lens exchange (RLE) with diffractive multifocal intraocular lenses (IOLs).

Setting: Clínica Oftalmológica das Antas, Porto, Portugal.

Design: Retrospective comparative study.

Methods: Refractive lens exchange was performed with implantation of an AT Lisa 839M (trifocal) or 909MP (bifocal toric) IOL, the latter if corneal astigmatism was more than 0.75 diopter (D). The postoperative visual and refractive outcomes were evaluated. A prototype light-distortion analyzer was used to quantify the postoperative light-distortion indices. A control group of eyes in which a Tecnis ZCB00 1-piece monofocal IOL was implanted had the same examinations.

Results: A trifocal or bifocal toric IOL was implanted in 66 eyes. The control IOL was implanted in 18 eyes. All 3 groups obtained a significant improvement in uncorrected distance visual acuity (UDVA) (P < .001) and corrected distance visual acuity (CDVA) (P = .001). The mean uncorrected near visual acuity (UNVA) was 0.123 logMAR with the trifocal IOL and 0.130 logMAR with the bifocal toric IOL. The residual refractive cylinder was less than 1.00 D in 86.7% of cases with the toric IOL. The mean light-distortion index was significantly higher in the multifocal IOL groups than in the monofocal group (P < .001), although no correlation was found between the light-distortion index and CDVA.

Conclusions: The multifocal IOLs provided excellent UDVA and functional UNVA despite increased light-distortion indices. The light-distortion analyzer reliably quantified a subjective component of vision distinct from visual acuity; it may become a useful adjunct in the evaluation of visual quality obtained with multifocal IOLs.

Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.
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http://dx.doi.org/10.1016/j.jcrs.2014.07.033DOI Listing
March 2015

Evaluation of visual acuity, macular status, and subfoveal choroidal thickness changes after cataract surgery in eyes with diabetic retinopathy.

Retina 2015 Feb;35(2):294-302

*Department of Ophthalmology, Hospital S. João, Alameda Prof. Hernâni Monteiro, Porto, Portugal; and †Department of Sense Organs, Faculty of Medicine of Porto University, Hospital S. João, Alameda Prof. Hernâni Monteiro, Porto, Portugal.

Purpose: Progression of diabetic macular edema has been reported as a common cause of poor visual acuity recovery after cataract surgery in patients with diabetes. Despite being responsible for the blood supply to the outer retina, the role of the choroidal layer in the pathogenesis of diabetic retinopathy (DR) is not yet understood. Our objective is to characterize macular and subfoveal choroidal thickness changes after cataract surgery in eyes with DR.

Methods: Thirty-five eyes with clinically significant cataract of patients with DR were divided into three groups based on clinical and optical coherence tomography findings: patients with DR without macular edema, patients with DR and macular thickening detected on optical coherence tomography, and finally patients with clinically significant macular edema. All cases were submitted to ophthalmologic examination and spectral domain optical coherence tomography 1 week before cataract surgery and repeated 1 month after surgery. Patients with preoperative clinically significant macular edema were treated with intravitreal bevacizumab at the time of surgery.

Results: All groups showed a significant increase in visual acuity 1 month after surgery (P < 0.001). Mean foveal thickness increased significantly in all groups, including controls (P = 0.013), except in patients who were simultaneously treated with intravitreal bevacizumab (P = 0.933). An increase of maximum macular thickness of at least 11% was found in 25.7% of the DR eyes, but no such increase occurred in the control eyes. No significant change was verified for subfoveal choroidal thickness in any of the studied groups.

Conclusion: Surgical inflammation associated with cataract surgery caused a significant increase of macular thickness in control and DR eyes that were not treated with intravitreous bevacizumab. Such macular changes were not accompanied by subfoveal choroidal thickness changes in any of the study groups, suggesting that the changes in macular thickness associated with the surgery are not related to changes in choroidal thickness and that there is no relation between inner blood-retinal barrier status and diabetic choroidal angiopathy.
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http://dx.doi.org/10.1097/IAE.0000000000000298DOI Listing
February 2015

Possible role for fundus autofluorescence as a predictive factor for visual acuity recovery after epiretinal membrane surgery.

Retina 2014 Feb;34(2):273-80

*Department of Ophthalmology, Hospital S. João, Alameda Prof. Hernâni Monteiro, Porto, Portugal; and †Faculty of Medicine of Porto, University of Porto, Alameda Prof. Hernâni Monteiro, Porto, Portugal.

Purpose: To study the potential association between fundus autofluorescence, spectral-domain optical coherence tomography, and visual acuity in patients undergoing surgery because of epiretinal membranes.

Methods: Prospective, interventional case series including 26 patients submitted to vitrectomy because of symptomatic epiretinal membranes. Preoperative evaluation consisted of a complete ophthalmologic examination, autofluorescence, and spectral-domain optical coherence tomography. Studied variables included foveal autofluorescence (fov.AF), photoreceptor inner segment/outer segment (IS/OS) junction line integrity, external limiting membrane integrity, central foveal thickness, and foveal morphology. All examinations were repeated at the first, third, and sixth postoperative months. The main outcome measures were logarithm of minimal angle resolution visual acuity, fov.AF integrity, and IS/OS integrity.

Results: All cases showing a continuous IS/OS line had an intact fov.AF, whereas patients with IS/OS disruption could have either an increased area of foveal hypoautofluorescence or an intact fov.AF, with the latter being associated with IS/OS integrity recovery in follow-up spectral-domain optical coherence tomography imaging. The only preoperative variables presenting a significant correlation with final visual acuity were baseline visual acuity (P = 0.047) and fov.AF grade (P = 0.023).

Conclusion: Recovery of IS/OS line integrity after surgery, in patients with preoperative IS/OS disruption and normal fov.AF, can be explained by the presence of a functional retinal pigment epithelium-photoreceptor complex, supporting normal photoreceptor activity. Autofluorescence imaging provides a functional component to the study of epiretinal membranes, complementing the structural information obtained with optical coherence tomography.
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http://dx.doi.org/10.1097/IAE.0b013e3182999a02DOI Listing
February 2014

Temporal evolution of lead isotope ratios in sediments of the Central Portuguese Margin: a fingerprint of human activities.

Mar Pollut Bull 2013 Sep 17;74(1):274-84. Epub 2013 Jul 17.

Instituto Português do Mar e da Atmosfera, I.P., Divisão de Oceanografia Ambiental e Bioprospecção, Av. Brasília, 1449-006 Lisboa, Portugal. Electronic address:

Stable Pb isotope ratios ((206)Pb/(207)Pb, (208)Pb/(206)Pb), (210)Pb, Pb, Al, Ca, Fe, Mn and Si concentrations were measured in 7 sediment cores from the west coast of the Iberian Peninsula to assess the Pb contamination throughout the last 200 years. Independently of their locations, all cores are characterized by increasing Pb/Al rends not related to grain-size changes. Conversely, decreasing trends of (206)Pb/(207)Pb were found towards the present. This tendency suggest a change in Pb sources reflecting an increased proportion derived from anthropogenic activities. The highest anthropogenic Pb inventories for sediments younger than 1950s were found in the two shallowest cores of Cascais and Lisboa submarine canyons, reflecting the proximity of the Tagus estuary. Lead isotope signatures also help demonstrate that sediments contaminated with Pb are not constrained to estuarine-coastal areas and upper parts of submarine canyons, but are also to transferred to a lesser extent to deeper parts of the Portuguese Margin.
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http://dx.doi.org/10.1016/j.marpolbul.2013.06.044DOI Listing
September 2013

Optical coherence tomography study of peripapillary retinal nerve fiber layer and choroidal thickness in eyes with tilted optic disc.

J Glaucoma 2015 Jan;24(1):45-50

*Department of Ophthalmology, Hospital S. João, Alameda Prof. Hernâni Monteiro †Faculty of Medicine, University of Porto, Porto, Portugal.

Purpose: The tilted optic disc is associated with peripapillary choroidal and retinal nerve fiber layer (RNFL) changes as well as visual field defects, often leading to diagnostic difficulties due to similarities with glaucomatous discs. We studied the peripapillary RNFL of the tilted optic disc by comparing values obtained with spectral-domain (SD) and time-domain (TD) optical coherence tomography (OCT) in order to identify characteristic RNFL patterns verified by both OCT devices, and also to determine whether SD-OCT offers any diagnostic advantage over TD-OCT.

Methods: Prospective case-control study of 16 individuals with tilted optic discs (27 eyes) and an age-matched control group (10 individuals, 20 eyes). Each case was subjected to ophthalmological examination and automated perimetry. Tilt orientation was classified based on observation of optic disc photographs, and angle of disc torsion was calculated with image processing software. RNFL measurements were obtained with TD-OCT and SD-OCT. Peripapillary choroid thickness was measured with SD-OCT. The findings were related with optic disc morphology and automated perimetry results.

Results: Stratus OCT results showed significantly lower superior RNFL (P<0.001) on the tilted group, whereas Spectralis indicated significantly lower superotemporal (P<0.001), superonasal (P=0.001), temporal (P=0.01), and global (P=0.01) RNFL on the tilted disc group. A significant correspondence was found between elevated disc rim and location of RNFL defect on the Spectralis (P=0.004). On the tilted group, peripapillary choroidal thickness was significantly thicker adjacent to the elevated rim (P<0.001). No correspondence was found between tilt orientation, peripapillary RNFL, or choroidal thickness and location of perimetric defects.

Conclusions: Our results provide a clinical characterization of the main tilted disc morphologies and are valuable for correctly differentiating a tilted disc from a myopic glaucomatous disc. RNFL assessment by Spectralis OCT seems to be more susceptible to altered disc morphologies. The peripapillary RNFL changes found on titled disc cases could not predict the location of visual field defects.
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http://dx.doi.org/10.1097/IJG.0b013e3182883c29DOI Listing
January 2015

Severe ocular hypertension secondary to systemic corticosteroid treatment in a child with nephrotic syndrome.

Clin Ophthalmol 2012 16;6:1675-9. Epub 2012 Oct 16.

Ophthalmology Department, Hospital S João, Porto, Portugal.

Purpose: To report a case of severe, acute ocular hypertension in a 6-year-old child, 7 days after initiating treatment with oral prednisolone, due to nephrotic syndrome.

Methods: A 6-year-old female Caucasian child was diagnosed with nephrotic syndrome and treated with oral prednisolone (60 mg/day). Seven days later the child initiated complaints of headache, vomiting, ocular pain, and photophobia. Ophthalmologic examination revealed a severely increased intraocular pressure (IOP) of 52 mmHg in the right eye and 56 mmHg in the left eye. Anterior segment morphology was evaluated with ultrasound biomicroscopy. Optic disc status was evaluated by disc photography, kinetic perimetry, and optical coherence tomography.

Results: Treatment was initiated with latanoprost, brimonidine, and the fixed association of timolol and dorzolamide. At each follow-up examination, progressively better control of IOP was obtained. Simultaneous with corticosteroid dosage decrease we were able to reduce antiglaucomatous medication while maintaining IOP under control. Ultrasound biomicroscopy revealed an open angle with normal anterior segment echographic findings. Perimetric evaluation revealed normal visual fields in both eyes. Four months after presentation, steroid treatment had been completed and IOP was 10 mmHg in both eyes without any antiglaucomatous medication. Optical coherence tomography revealed normal retinal nerve fiber layer thickness in all peripapillary sectors.

Conclusions: Systemic steroid treatment can cause a severe, acute increase in IOP in children. Children undergoing steroid treatment should have routine ophthalmologic examinations during treatment duration. Prompt antiglaucomatous treatment prevents retinal nerve fiber layer damage and visual acuity loss.
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http://dx.doi.org/10.2147/OPTH.S36261DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3476485PMC
October 2012

The importance of the optical properties in dental silica-based ceramics.

J Calif Dent Assoc 2012 Jun;40(6):476-81

CiiEM (Centro de Investigação Interdisciplinar Egas Moniz), Instituto Superior de Ciências da Saúde Egas Moniz, Caparica, Portugal.

To make esthetic rehabilitation similar to the natural teeth, all-ceramic restorations must have equal optical properties to the natural teeth in terms of color, translucency, fluorescence, and opalescence. Furthermore, a correct communication process with the laboratory is the key to success and biointegration with the ceramic indirect restoration and the teeth.
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June 2012

Morphology of spermatozoa of Dissomphalus connubialis (Ashmead, 1893) (Hymenoptera: Bethylidae).

Micron 2013 Jan 24;44:268-74. Epub 2012 Jul 24.

Departamento de Biologia Geral, Universidade Federal de Viçosa-UFV, Minas Gerais, Brazil.

In this study, the morphology of spermatozoa of Bethylidae Dissomphalus connubialis (Pristocerinae) was analyzed using light and transmission electron microscopy. Spermatozoa of this species are thin, measure approximately 130 μm in length and comprise a head region and flagellum region. The head is formed by the acrosome and nucleus. The acrosome consists of the acrosome vesicle and the perforatorium, the posterior portion of which is inserted into a cavity at the anterior extremity of the nucleus. The nucleus is compact, electron-dense and measures 15 μm in length. The flagellum possesses two mitochondrial derivatives, two accessory bodies and one axoneme with a 9+9+2 microtubular pattern. The nucleus is connected to the flagellum by the centriole adjunct. Mitochondrial derivatives are compact, apparently without paracrystalline material and with rare mitochondrial cristae. They are asymmetric in length, such that the larger mitochondrial derivative begins parallel to the posterior region of the nucleus and the smaller mitochondrial derivative begins just below the centriole adjunct. The basic structure of spermatozoa of D. connubialis is similar to that of other Aculeata studied. However, this species shows characteristics not seen in other Hymenoptera, such as the wide electron-lucid region that separates the acrosomal vesicle from the perforatorium and the depth of the cavity in the anterior extremity of the nucleus, into which the base of the perforatorium is inserted. There are also characteristics that distinguish this species from Bethylidae Prorops nasuta, including the fact that one of the mitochondrial derivatives lies to parallel to the nucleus over a long distance, the small quantity of cristae, the absence of paracrystalline material in these organelles, and the fact that the accessory microtubules are the first to terminate in the final portion of the flagellum.
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http://dx.doi.org/10.1016/j.micron.2012.07.004DOI Listing
January 2013