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1.
PLoS One ; 19(3): e0299958, 2024.
Article in English | MEDLINE | ID: mdl-38446809

ABSTRACT

In around 716 AD, the city of Santarém, Portugal, was conquered by the Berber and Arab armies that swept the Iberian Peninsula and went on to rule the region until the 12th century. Archaeological excavations in 2007/08 discovered an Islamic necropolis (Avenida 5 de Outubro #2-8) that appears to contain the remains of an early Muslim population in Santarém (8th- 10th century). In this study, skeletal material from 58 adult individuals was analysed for stable carbon (δ13Ccol; δ13Cap), nitrogen (δ15N) and sulphur (δ34S) isotope ratios in bones, and stable oxygen (δ18O), carbon (δ13Cen) and radiogenic strontium (87Sr/86Sr) isotopes in tooth enamel. The results of this study revealed a dietary pattern of predominantly C3-plant and domestic C3-fed herbivore consumption during adulthood (δ13Ccol and δ15N, respectively) but a higher proportion of C4-plant input during childhood (δ13Cen) for some individuals-interpreted as possible childhood consumption of millet porridge, a common practice in North Africa-in those with unorthodox burial types (Groups 1 and 2) that was not practiced in the individuals with canonical burials (Group 3). In this first mobility study of a medieval Muslim population in Portugal, δ18ODW values revealed greater heterogeneity in Groups 1 and 2, consistent with diverse origins, some in more humid regions than Santarém when compared to regional precipitation δ18O data, contrasting the more homogenous Group 3, consistent with the local precipitation δ18O range. Ancient DNA analysis conducted on three individuals revealed maternal (mtDNA) and paternal (Y-chromosome) lineages compatible with a North African origin for (at least) some of the individuals. Additionally, mobility of females in this population was higher than males, potentially resulting from a patrilocal social system, practiced in Berber and Arab communities. These results serve to offer a more detailed insight into the ancestry and cultural practices of early Muslim populations in Iberia.


Subject(s)
Islam , Strontium Isotopes , Humans , Adult , Female , Male , Portugal , Carbon
2.
Infect Dis Rep ; 16(1): 83-92, 2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38391584

ABSTRACT

Lophomonas are flagellated protozoa that have been increasingly associated with upper and lower airway infection in humans. The prevalence and characterization of this disease in the critically ill remains poorly understood. We present a series of eleven ICU patients with confirmed Lophomonas spp. identification in respiratory samples.

3.
Anthropol Anz ; 81(2): 139-151, 2024 Mar 21.
Article in English | MEDLINE | ID: mdl-37580945

ABSTRACT

Objectives: The aim of this study is to evaluate the internal consistency of sex estimation using metric (long bone length) and morphological (os coxae) methodologies from different bones and across different archaeological populations from different regions. Materials and Methods: Sex was estimated using characteristics of the pelvis and compared with sex estimations using long bone length. Portuguese (659 females; 906 males) and English (141 females; 277 males) archaeological collections were analysed in this study. A set of long bone length functions were developed using one of the archaeological collections (531 females; 600 males) and its coincidence with sex estimated from the pelvis was compared to the coincidence between the pelvis and long bone length sex estimations using functions developed from contemporary collections. Intra- and inter-observer errors were calculated, as well as the sexual dimorphism index for each bone and osteological collection. Results: The accuracy of the developed functions and the other methods tested is highly variable, ranging between 25 and 100%. The accuracy of the standard forensic methods varied between collections and analysed bones. Discussion: This study reinforces that long bone length is highly population-specific, even between samples of close chronology and geography. Metric methods are good options to strengthen the sex estimations, but they need to be carefully chosen and always report the estimated probability of being male or female in either forensic or archaeological analysis.


Subject(s)
Pelvic Bones , Sex Determination by Skeleton , Humans , Male , Female , Forensic Anthropology/methods , Sex Determination by Skeleton/methods , Pelvic Bones/diagnostic imaging , Pelvic Bones/anatomy & histology , Pelvis , Sex Characteristics , Discriminant Analysis
4.
Case Rep Infect Dis ; 2023: 4412935, 2023.
Article in English | MEDLINE | ID: mdl-37261247

ABSTRACT

Strongyloidiasis develops from the infection with Strongyloides stercoralis (Family: Strongylidae) and was recently considered a neglected tropical disease by the World Health Organization due to its global distribution and high burden of infection. Here, we present the cases of two patients under corticosteroid therapy after neurosurgical surgery who developed septic shock-like hyperinfection syndrome due to disseminated strongyloidiasis. The first case is a 77-year-old man from Cape Verde who was diagnosed with an extra-axial right parietal brain mass. He was given dexamethasone and was submitted to a biparietal craniotomy. His condition deteriorated and he was admitted to the intensive care unit (ICU), where he was diagnosed with disseminated strongyloidiasis with hyperinfection. Anthelmintic treatment and corticosteroid therapy were rapidly tapered and stopped. Neurological dysfunction persisted and the patient was transferred to the ward. The patient had died after complications of hospital-acquired pneumonia. The second case is a 47-year-old man from Guinea-Bissau who was diagnosed with a space-occupying lesion in the right temporal region and started treatment with dexamethasone. He underwent a craniectomy with partial excision of the lesion (high-grade glioma). Later his neurologic state worsened, and he was diagnosed with septic shock and hospital-acquired pneumonia. He was admitted to the ICU, the diagnosis of disseminated strongyloidiasis and hyperinfection syndrome was made and he initiated treatment with ivermectin and albendazole. Corticosteroid therapy was tapered. The patient's clinical status deteriorated, and multiple opportunistic infections were diagnosed during the ICU stay, which lead him to die. Clinicians should have a high index of suspicion when in the presence of corticosteroid-treated patients with sepsis. Preventive strategies and subsequent treatment should be considered in patients with a risk of acquisition or dissemination. Treating severe strongyloidiasis is still a clinical challenge and a delayed diagnosis can significantly worsen the outcomes of the patients affected, as seen in the presented cases.

5.
ALTEX ; 40(1): 125-140, 2023.
Article in English | MEDLINE | ID: mdl-35796348

ABSTRACT

Manufacturing and functionalizing materials at the nanoscale has led to the generation of a whole array of nanoforms (NFs) of substances varying in size, morphology, and surface characteristics. Due to financial, time, and ethical considerations, testing every unique NF for adverse effects is virtually impossible. Use of hypothesis-driven grouping and read-across approaches, as supported by the GRACIOUS Framework, represents a promising alternative to case-by-case testing that will make the risk assessment process more efficient. Through application of appropriate grouping hypotheses, the Framework facilitates the assessment of similarity between NFs, thereby supporting grouping and read-across of information, minimizing the need for new testing, and aligning with the 3R principles of replacement, reduction, and refinement of animals in toxicology studies. For each grouping hypothesis an integrated approach to testing and assessment (IATA) guides the user in data gathering and acquisition to test the hypothesis, following a structured format to facilitate efficient decision-making. Here we present the template used to generate the GRACIOUS grouping hypotheses encompassing information relevant to "Lifecycle, environmental release, and human exposure", "What they are: physicochemical characteristics", "Where they go: environmental fate, uptake, and toxicokinetics", and "What they do: human and environmental toxicity". A summary of the template-derived hypotheses focusing on human health is provided, along with an overview of the IATAs generated by the GRACIOUS project. We discuss the application and flexibility of the template, providing the opportunity to expand the application of grouping and read-across in a logical, evidence-based manner to a wider range of NFs and substances.


Subject(s)
Hazardous Substances , Animals , Humans , Risk Assessment , Hazardous Substances/toxicity , Hazardous Substances/chemistry , Toxicokinetics
6.
Part Fibre Toxicol ; 19(1): 50, 2022 07 20.
Article in English | MEDLINE | ID: mdl-35854357

ABSTRACT

BACKGROUND: The EU-project GRACIOUS developed an Integrated Approach to Testing and Assessment (IATA) to support grouping high aspect ratio nanomaterials (HARNs) presenting a similar inhalation hazard. Application of grouping reduces the need to assess toxicity on a case-by-case basis and supports read-across of hazard data from substances that have the data required for risk assessment (source) to those that lack such data (target). The HARN IATA, based on the fibre paradigm for pathogenic fibres, facilitates structured data gathering to propose groups of similar HARN and to support read-across by prompting users to address relevant questions regarding HARN morphology, biopersistence and inflammatory potential. The IATA is structured in tiers, allowing grouping decisions to be made using simple in vitro or in silico methods in Tier1 progressing to in vivo approaches at the highest Tier3. Here we present a case-study testing the applicability of GRACIOUS IATA to form an evidence-based group of multiwalled carbon nanotubes (MWCNT) posing a similar predicted fibre-hazard, to support read-across and reduce the burden of toxicity testing. RESULTS: The case-study uses data on 15 different MWCNT, obtained from the published literature. By following the IATA, a group of 2 MWCNT was identified (NRCWE006 and NM-401) based on a high degree of similarity. A pairwise similarity assessment was subsequently conducted between the grouped MWCNT to evaluate the potential to conduct read-across and fill data gaps required for regulatory hazard assessment. The similarity assessment, based on expert judgement of Tier 1 assay results, predicts both MWCNT are likely to cause a similar acute in vivo hazard. This result supports the possibility for read-across of sub-chronic and chronic hazard endpoint data for lung fibrosis and carcinogenicity between the 2 grouped MWCNT. The implications of accepting the similarity assessment based on expert judgement of the MWCNT group are considered to stimulate future discussion on the level of similarity between group members considered sufficient to allow regulatory acceptance of a read-across argument. CONCLUSION: This proof-of-concept case-study demonstrates how a grouping hypothesis and IATA may be used to support a nuanced and evidence-based grouping of 'similar' MWCNT and the subsequent interpolation of data between group members to streamline the hazard assessment process.


Subject(s)
Nanotubes, Carbon , Pulmonary Fibrosis , Administration, Inhalation , Humans , Lung , Nanotubes, Carbon/toxicity , Toxicity Tests/methods
7.
Euro Surveill ; 27(22)2022 06.
Article in English | MEDLINE | ID: mdl-35656830

ABSTRACT

Up to 27 May 2022, Portugal has detected 96 confirmed cases of monkeypox. We describe 27 confirmed cases (median age: 33 years (range: 22-51); all males), with an earliest symptom onset date of 29 April. Almost all cases (n = 25) live in the Lisbon and Tagus Valley health region. Most cases were neither part of identified transmission chains, nor linked to travel or had contact with symptomatic persons or with animals, suggesting the possible previously undetected spread of monkeypox.


Subject(s)
Monkeypox virus , Mpox (monkeypox) , Disease Outbreaks , Humans , Male , Mpox (monkeypox)/diagnosis , Mpox (monkeypox)/epidemiology , Monkeypox virus/genetics , Portugal/epidemiology , Travel
8.
Int J Paleopathol ; 38: 13-17, 2022 09.
Article in English | MEDLINE | ID: mdl-35700547

ABSTRACT

OBJECTIVE: This study describes foot bone anomalies and the degenerative changes associated with locomotion adaptations. MATERIALS: An adult male (approximately 29-46 years old) from Estremoz, Portugal (13th-15th century). METHODS: The skeletal anomalies observed in this skeleton were described and measurements were compared between both sides of the individual and with the mean of the adult males from the same collection. RESULTS: The most anomalous bones are the right medial cuneiform and metatarsals. Degenerative changes are more severe on the left lower limb and right upper limb. CONCLUSIONS: This skeleton represents a unilateral case of talipes varus of the right foot, with the metatarsals being more affected while previously published cases show more severe anomalies of the hindfoot. The degenerative changes observed in the skeleton suggest that both legs and arms, aided by crutches, were used for locomotion. SIGNIFICANCE: This case shows that club foot skeletal anomalies are variable and the pattern of bony changes throughout the body can reveal locomotion adaptations. LIMITATIONS: The possibility of a genetic cause cannot be assessed due to the absence of paleogenomic data. SUGGESTIONS FOR FURTHER RESEARCH: Since the anomalies found in this case are different than those previously published, we recommend care when analysing foot bones.


Subject(s)
Clubfoot , Metatarsal Bones , Adult , Foot , Humans , Locomotion , Male , Middle Aged , Portugal
9.
Environ Toxicol Chem ; 41(6): 1390-1406, 2022 06.
Article in English | MEDLINE | ID: mdl-35226375

ABSTRACT

An integrated testing strategy for ecotoxicity assessment (ITS-ECO) was developed to aid in the hazard and fate assessment of engineered nanomaterials (ENMs) deposited in marine environments using the bivalve Mytilus spp. as a test species. The ENMs copper(II) oxide (CuO) and titanium dioxide (TiO2 ), either in pristine form (core) or with functionalized coatings (polyethylene glycol [PEG], carboxyl [COOH], and ammonia [NH3 ]) were selected as case study materials based on their production levels and use. High-throughput in vitro testing in Tier 1 of the ITS-ECO revealed CuO ENMs to elicit cytotoxic effects on lysosomes of hemocytes of mussels, with the hazard potential CuO PEG > CuO COOH > CuO NH3 > CuO core, whereas TiO2 ENMs were not cytotoxic. Genotoxicity in hemocytes as well as gill cells of mussels following in vivo exposure (48 h) to CuO ENMs was also seen. Longer in vivo exposures in Tier 2 (48 h-21 days) revealed subacute and chronic oxidative effects for both CuO and TiO2 ENMs, in some cases leading to lipid peroxidation (core TiO2 ENMs). In Tier 3 bioaccumulation studies, distinct patterns of uptake for Cu (predominantly in gills) and Ti (predominantly in digestive glands) and between the different core and coated ENMs were found. Clear NM-specific and coating-dependent effects on hazard and fate were seen. Overall, using a tiered testing approach, the ITS-ECO was able to differentiate the hazard (acute, subacute, and chronic effects) posed by ENMs of different compositions and coatings and to provide information on fate for environmental risk assessment of these ENMs. Environ Toxicol Chem 2022;41:1390-1406. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Subject(s)
Mytilus , Nanostructures , Animals , Copper/toxicity , Nanostructures/chemistry , Nanostructures/toxicity , Titanium
10.
Int J Legal Med ; 136(3): 955-962, 2022 May.
Article in English | MEDLINE | ID: mdl-34677683

ABSTRACT

The importance of reference osteological collections is unquestionable. However, the development of methodologies is more reliable the closer the collection is socioeconomically, demographically, and genetically to the population under study. The purpose of this study is to characterize and contextualize a new Portuguese reference collection. The collection of identified skeletons from the University of Évora comprises 201 adults of both sexes and seven non-adults, deceased between 1870 and 1993 and born between 1790 and 1969. It consists almost exclusively of individuals who were born and died in inland Alentejo, being the only Portuguese collection with this characteristic. The collection was built following all current legal and ethical obligations. Due to its characteristics, the collection constitutes a fundamental tool for forensic and bioarchaeological research in the inland regions of Portugal. In addition to the possibility offered to develop and validate methodologies in both sciences, the available complete hospital archives for research make this collection unique for health studies before, during, and after the epidemiological transition.


Subject(s)
Archaeology , Forensic Anthropology , Adult , Bone and Bones , Female , Forensic Sciences , Humans , Male , Portugal
11.
Microorganisms ; 9(10)2021 Sep 28.
Article in English | MEDLINE | ID: mdl-34683365

ABSTRACT

Malaria is one of the 'big three' killer infectious diseases, alongside tuberculosis and HIV. In non-endemic areas, malaria may occur in travelers who have recently been to or visited endemic regions. The number of imported malaria cases in Portugal has increased in recent years, mostly due to the close relationship with the community of Portuguese language countries. Samples were collected from malaria-infected patients attending Centro Hospitalar Lisboa Ocidental (CHLO) or the outpatient clinic of Instituto de Higiene e Medicina Tropical (IHMT-NOVA) between March 2014 and May 2021. Molecular characterization of Plasmodium falciparum pfk13 and pfmdr1 genes was performed. We analyzed 232 imported malaria cases. The majority (68.53%) of the patients came from Angola and only three patients travelled to a non-African country; one to Brazil and two to Indonesia. P. falciparum was diagnosed in 81.47% of the cases, P. malariae in 7.33%, P. ovale 6.47% and 1.72% carried P. vivax. No mutations were detected in pfk13. Regarding pfmdr1, the wild-type haplotype (N86/Y184/D1246) was also the most prevalent (64.71%) and N86/184F/D1246 was detected in 26.47% of the cases. The typical imported malaria case was middle-aged male, traveling from Angola, infected with P. falciparum carrying wild type pfmdr1 and pfk13. Our study highlights the need for constant surveillance of malaria parasites imported into Portugal as an important pillar of public health.

12.
Int J Infect Dis ; 110: 151-154, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34242769

ABSTRACT

The failure of artemisinin combination therapy (ACT) in malaria patients returning from endemic regions may be driven by parasite resistance to this treatment. ACT is used globally as the first-line treatment for Plasmodium falciparum malaria. However, artemisinin-resistant strains of P. falciparum have emerged and spread across Southeast Asia, with the risk of reaching high malaria burden regions in Africa and elsewhere. Here, we report on two malaria imported cases from Africa with possible parasite resistance to the ACT artemether-lumefantrine (AL). Case presentation: Two middle-aged males returning from Angola and Mozambique developed malaria symptoms in Portugal, where they were diagnosed and received treatment with AL as hospital inpatients. After apparent cure and discharge from hospital, these individuals returned to hospital showing signs of late clinical failure. Molecular analysis was performed across a number of drug resistance associated genes. No evidence of pfk13-mediated artemisinin resistance was found. Both subjects had complete parasite clearance after treatment with non-ACT antimalarials. Conclusion: Our case-studies highlights the need for close monitoring of signs of unsatisfactory antimalarial efficacy among AL treated patients and the possible implication of other genes or mutations in the parasite response to ACTs.


Subject(s)
Antimalarials , Malaria, Falciparum , Angola/epidemiology , Antimalarials/therapeutic use , Artemether/therapeutic use , Artemether, Lumefantrine Drug Combination/therapeutic use , Humans , Malaria, Falciparum/drug therapy , Malaria, Falciparum/epidemiology , Male , Middle Aged , Mozambique/epidemiology , Plasmodium falciparum/genetics , Treatment Failure
13.
NanoImpact ; 21: 100291, 2021 01.
Article in English | MEDLINE | ID: mdl-35559780

ABSTRACT

The use of silver (Ag) and titanium dioxide (TiO2) nanomaterials (NMs) in industrial processes and consumer products has experienced considerable growth since the late 20th century. Throughout their lifecycle, both Ag NM and TiO2NM are released into the environment, with benthic systems anticipated to be the final sink. Their potential toxicity towards benthic species is therefore of major concern. This study investigated the toxicity of silver (Ag; NM-300 K) and titanium dioxide (TiO2; NM-104) NMs to the freshwater oligochaete, Lumbriculus variegatus in acute (0-96-h) waterborne and chronic (28-d) sediment studies. Toxicity was investigated via assessment of mortality, behaviour, and antioxidant enzyme activity. The 96-h LC50 for Ag NMs in water was 0.51 mg/l (95% CI, 0.45-0.56), with L. variegatus displaying inhibited predation-avoidance behaviour compared to controls (6.66 ± 10%) successful response at 24-h), as well as significant increases (p < 0.05) in catalase (CAT) activity at sub-lethal concentrations at 24-h. Behavioural improvement and the return of antioxidant enzymes to control levels was observed after 48 and 72-h. AgNO3 exposure proved more toxic than Ag NM (96-h LC50 = 0.034 mg/l, 95% CI, 0.031-0.037) but resulted in no changes to antioxidant enzymes following sub-lethal exposure. Furthermore, Ag dissolution from Ag NM (~2-4%) could not account for the full extent of toxicity observed, suggesting a nano-specific effect. Increased environmental relevance via the inclusion of Suwannee River Humic Acid (SRHA, 5 mg/l) alleviated sub-lethal Ag NM toxicity despite a comparable 96-h LC50 (0.54 mg/l, 95% CI, 0.51-0.57). Significant effects of Ag NMs in formulated sediments (mortality, biomass) were only recorded according to OECD 225 at the highest test concentration (1333 mg/kg) for Ag NM indicating a potential attenuating effect of sediments towards toxicity. No toxicity was observed for TiO2 NM in aquatic or sediment exposures up to concentrations of 2000 mg/l and 1333 mg/kg, respectively.


Subject(s)
Nanostructures , Oligochaeta , Water Pollutants, Chemical , Animals , Antioxidants/pharmacology , Nanostructures/toxicity , Silver/toxicity , Titanium , Water Pollutants, Chemical/toxicity
14.
NanoImpact ; 22: 100314, 2021 04.
Article in English | MEDLINE | ID: mdl-35559971

ABSTRACT

Here we describe the development of an Integrated Approach to Testing and Assessment (IATA) to support the grouping of different types (nanoforms; NFs) of High Aspect Ratio Nanomaterials (HARNs), based on their potential to cause mesothelioma. Hazards posed by the inhalation of HARNs are of particular concern as they exhibit physical characteristics similar to pathogenic asbestos fibres. The approach for grouping HARNs presented here is part of a framework to provide guidance and tools to group similar NFs and aims to reduce the need to assess toxicity on a case-by-case basis. The approach to grouping is hypothesis-driven, in which the hypothesis is based on scientific evidence linking critical physicochemical descriptors for NFs to defined fate/toxicokinetic and hazard outcomes. The HARN IATA prompts users to address relevant questions (at decision nodes; DNs) regarding the morphology, biopersistence and inflammatory potential of the HARNs under investigation to provide the necessary evidence to accept or reject the grouping hypothesis. Each DN in the IATA is addressed in a tiered manner, using data from simple in vitro or in silico methods in the lowest tier or from in vivo approaches in the highest tier. For these proposed methods we provide justification for the critical descriptors and thresholds that allow grouping decisions to be made. Application of the IATA allows the user to selectively identify HARNs which may pose a mesothelioma hazard, as demonstrated through a literature-based case study. By promoting the use of alternative, non-rodent approaches such as in silico modelling, in vitro and cell-free tests in the initial tiers, the IATA testing strategy streamlines information gathering at all stages of innovation through to regulatory risk assessment while reducing the ethical, time and economic burden of testing.


Subject(s)
Asbestos , Mesothelioma, Malignant , Mesothelioma , Nanostructures , Asbestos/toxicity , Humans , Mesothelioma/chemically induced , Nanostructures/adverse effects , Risk Assessment/methods
15.
Materials (Basel) ; 13(20)2020 Oct 13.
Article in English | MEDLINE | ID: mdl-33066064

ABSTRACT

The convergence of nanotechnology and biotechnology has led to substantial advancements in nano-biomaterials (NBMs) used in medical devices (MD) and advanced therapy medicinal products (ATMP). However, there are concerns that applications of NBMs for medical diagnostics, therapeutics and regenerative medicine could also pose health and/or environmental risks since the current understanding of their safety is incomplete. A scientific strategy is therefore needed to assess all risks emerging along the life cycles of these products. To address this need, an overarching risk management framework (RMF) for NBMs used in MD and ATMP is presented in this paper, as a result of a collaborative effort of a team of experts within the EU Project BIORIMA and with relevant inputs from external stakeholders. The framework, in line with current regulatory requirements, is designed according to state-of-the-art approaches to risk assessment and management of both nanomaterials and biomaterials. The collection/generation of data for NBMs safety assessment is based on innovative integrated approaches to testing and assessment (IATA). The framework can support stakeholders (e.g., manufacturers, regulators, consultants) in systematically assessing not only patient safety but also occupational (including healthcare workers) and environmental risks along the life cycle of MD and ATMP. The outputs of the framework enable the user to identify suitable safe(r)-by-design alternatives and/or risk management measures and to compare the risks of NBMs to their (clinical) benefits, based on efficacy, quality and cost criteria, in order to inform robust risk management decision-making.

17.
Sci Total Environ ; 715: 136941, 2020 May 01.
Article in English | MEDLINE | ID: mdl-32041050

ABSTRACT

Lead-halide perovskite nanoparticles (NPs) are a new technology, and investigation of toxicity is of considerable importance due to the potential lead (Pb) release into the environment. The aim of the study was to investigate aqueous and dietary toxicity of Pb-halide perovskite NP and Pb in zebrafish Danio rerio. Perovskite NP toxicity was evaluated in zebrafish by mortality, gene expression, histopathology, and phylogenetic analysis of gut microbiota. Zebrafish larvae were exposed to five Pb-halide perovskite NPs in parallel with Pb(NO3)2 exposures, and zebrafish adults were exposed to the three perovskite NPs that caused the strongest effect and Pb(NO3)2. No median lethal concentration (LC50) was observed for zebrafish larvae exposed to up to 200 mg/L of perovskite NPs for 96 h. Mortality, metallothionein 2 (mt2) and δ-aminolevulinic acid dehydratase (ala-d) gene expression (24-h exposure) in zebrafish larvae after aqueous perovskite NPs exposures did not differ from total Pb concentration - response curves. The lack of differences in mortality and gene expression between perovskite NPs and soluble Pb after aqueous exposure suggest that toxicity from perovskite NPs can be attributed to bioavailable Pb rather than nano-specific effects. Induction of mt2 and reduction of ala-d expression levels in liver tissues showed Pb bioavailability after 2-d and 4-d dietary exposure to perovskite-spiked feeds. Changes in gut microbiota of adult zebrafish were detected after 14-d exposure to Pb-spiked food, but no changes were detected from perovskite-NP spiked food. The phylogenetic analysis identified different microbiome profiles of Pb-fed fish compared to perovskite-fed fish suggesting a different mechanism of toxicity. Exposure to Pb-halide perovskite NPs led to absorption of Pb likely from release of Pb ions rather than absorption of NPs. Pb-halide perovskite NPs can release bioavailable Pb and this needs to be considered during the development of this technology.


Subject(s)
Gastrointestinal Microbiome , Metal Nanoparticles , Animals , Calcium Compounds , Lead , Oxides , Phylogeny , Titanium , Water Pollutants, Chemical , Zebrafish
18.
Environ Toxicol Chem ; 39(2): 287-299, 2020 02.
Article in English | MEDLINE | ID: mdl-31610609

ABSTRACT

We evaluated the effect of copper oxide nanomaterials (CuO NMs), uncoated and with 3 different surface coatings (carboxylated, pegylated, and ammonia groups), on acute toxicity and accumulation dynamics in Daphnia magna. With the use of biodynamic modelling, biosorption and elimination rate constants were determined for D. magna following waterborne exposure to dissolved Cu and CuO NMs. The relationship between modeled parameters and acute toxicity endpoints was evaluated to investigate whether accumulation dynamics parameters could be used as a predictor of acute toxicity. The Langmuir equation was used to characterize the biosorption dynamics of Cu NMs and Cu chloride, used as dissolved Cu control. Uptake rates showed the following NM rankings: pristine-CuO > NH3 -CuO > aqueous Cu > polyethylene glycol (PEG)-CuO > COOH-CuO. To determine Cu elimination by D. magna, a one-compartment model was used. Different elimination rate constants were estimated for each chemical substance tested. Those that were easily biosorbed were also easily removed from organisms. Biosorption and depuration properties of NMs were correlated with zeta potential values and diameters of NM agglomerates in the suspensions. No link was found between biosorption and toxicity. Waterborne exposures to more difficult-to-biosorb CuO NMs were more likely to induce adverse effects than those that biosorbed easily. It is proposed that some physicochemical properties of NMs in media, including zeta potential and agglomerate diameter, can lead to higher biosorption but do not necessarily affect toxicity. The mode of interaction of the NMs with the organism seems to be complex and to depend on chemical speciation and physicochemical properties of the NMs inside an organism. Moreover, our findings highlight that coating type affects the biosorption dynamics, depuration kinetics, and dissolution rate of NMs in media. Environ Toxicol Chem 2020;39:287-299. © 2019 SETAC.


Subject(s)
Copper/toxicity , Daphnia/drug effects , Nanostructures/toxicity , Water Pollutants, Chemical/toxicity , Animals , Bioaccumulation , Copper/metabolism , Daphnia/metabolism , Models, Biological , Nanostructures/chemistry , Solubility , Surface Properties , Water/chemistry , Water Pollutants, Chemical/metabolism
19.
Am J Phys Anthropol ; 171(2): 285-297, 2020 02.
Article in English | MEDLINE | ID: mdl-31702830

ABSTRACT

INTRODUCTION: Physiological stress is one of the various factors that can have an impact on stable isotope ratios. However, its effect on bone collagen stable isotope ratios is still not fully understood. This study aims to build on previous research on how different disease stages may affect bone collagen stable isotope ratios. MATERIALS AND METHODS: Carbon (δ13 C) and nitrogen (δ15 N) isotope ratios were assessed in 33 skeletons that retained evidence of infectious disease and healed fractures. Samples were taken from active lesions (long bones n = 14; ribs n = 4), healed lesions (long bones n = 10; ribs n = 9), or a fracture callus (long bones n = 9; ribs n = 3). Results were compared to stable isotope ratios calculated for regions on these bones that did not retain evidence of disease or fracture. RESULTS: Long bones with active lesions had a significantly higher average δ15 N (δ15 N = 11.1 ± 0.9‰) compared to those without lesions (δ15 N = 10.7 ± 0.7‰; p = .02), while fracture calluses showed the largest range for both δ15 N and δ13 C. There were no significant differences in stable isotope ratios when compared between nonlesion and lesion sites in the ribs. DISCUSSION: The increase in δ15 N seen in active lesions, when compared with δ15 N from nonlesion regions on the same long bone, may be a consequence of altered protein metabolism. The high variability of δ15 N and δ13 C in fractures may be related to different healing stages of the calluses. This study suggests that stable isotope data can contribute information about diseases in the past, as well as an individual's response to diseases in the absence of modern medicine and antibiotics.


Subject(s)
Bone and Bones/chemistry , Fracture Healing , Adult , Aged , Bone Diseases/physiopathology , Carbon Isotopes/analysis , Female , Fractures, Bone/physiopathology , Humans , Male , Middle Aged , Nitrogen Isotopes/analysis , Portugal , Young Adult
20.
PeerJ ; 7: e7314, 2019.
Article in English | MEDLINE | ID: mdl-31428537

ABSTRACT

Mitochondrial DNA (mtDNA) presents several characteristics useful for forensic studies, especially related to the lack of recombination, to a high copy number, and to matrilineal inheritance. mtDNA typing based on sequences of the control region or full genomic sequences analysis is used to analyze a variety of forensic samples such as old bones, teeth and hair, as well as other biological samples where the DNA content is low. Evaluation and reporting of the results requires careful consideration of biological issues as well as other issues such as nomenclature and reference population databases. In this work we review mitochondrial DNA profiling methods used for human identification and present their use in the main cases of humanidentification focusing on the most relevant issues for forensics.

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