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1.
Environ Pollut ; 302: 119054, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35219792

RESUMO

Perfluorooctane sulfonate (PFOS) is among the most commonly per- and poly-fluoroalkyl substances (PFAS) found in environmental samples. Nevertheless, the effect of this legacy persistent organic contaminant has never been investigated on corals to date. Corals are the keystone organisms of coral reef ecosystems and sensitive to rising ocean temperatures, but it is not understood how the combination of elevated temperature and PFOS exposure will affect them. Therefore, the aims of the present study were (1) to evaluate the time-dependent bioconcentration and depuration of PFOS in the scleractinian coral Stylophora pistillata using a range of PFOS exposure concentrations, and (2) to assess the individual and combined effects of PFOS exposure and elevated seawater temperature on key physiological parameters of the corals. Our results show that the coral S. pistillata rapidly bioconcentrates PFOS from the seawater and eliminates it 14 days after ceasing the exposure. We also observed an antagonistic effect between elevated temperature and PFOS exposure. Indeed, a significantly reduced PFOS bioconcentration was observed at high temperature, likely due to a loss of symbionts and a higher removal of mucus compared to ambient temperature. Finally, concentrations of PFOS consistent with ranges observed in surface waters were non-lethal to corals, in the absence of other stressors. However, PFOS increased lipid peroxidation in coral tissue, which is an indicator of oxidative stress and enhanced the thermal stress-induced impairment of coral physiology. This study provides valuable insights into the combined effects of PFOS exposure and ocean warming for coral's physiology. PFOS is usually the most prevalent but not the only PFAS defected in reef waters, and thus it will be also important to monitor PFAS mixture concentrations in the oceans and to study their combined effects on aquatic wildlife.


Assuntos
Antozoários , Fluorocarbonos , Ácidos Alcanossulfônicos , Animais , Antozoários/fisiologia , Recifes de Corais , Ecossistema , Fluorocarbonos/toxicidade , Temperatura Alta , Estresse Oxidativo
2.
Cancer Radiother ; 23(2): 147-150, 2019 Apr.
Artigo em Francês | MEDLINE | ID: mdl-30904418

RESUMO

Whereas immune checkpoint inhibitors of serine/threonine protein kinase B-raf therapy dramatically changed metastatic outcomes of patients with melanoma, they remain at high risk of brain extension. Additional local treatment can be offered in this situation such as surgery and or stereotactic radiotherapy. In this review article, we describe the different options with published data and their optimal timing.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/terapia , Melanoma/secundário , Melanoma/terapia , Antineoplásicos Imunológicos/uso terapêutico , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Antígeno CTLA-4/antagonistas & inibidores , Fracionamento da Dose de Radiação , Humanos , Melanoma/patologia , Mutação , Necrose/etiologia , Necrose/prevenção & controle , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Radiocirurgia , Neoplasias Cutâneas/patologia
3.
Aquat Toxicol ; 200: 247-256, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29803165

RESUMO

Corals are the main reef builders through the formation of calcium carbonate skeletons. In recent decades, coral calcification has however been impacted by many global (climate change) and local stressors (such as destructive fishing practices and changes in water quality). In this particular context, it is crucial to identify and characterize the various factors that promote coral calcification. We thus performed the first investigation of the effect of nickel and urea enrichment on the calcification rates of three coral species. These two factors may indeed interact with calcification through the activity of urease, which catalyzes the hydrolysis of urea to produce inorganic carbon and ammonia that are involved in the calcification process. Experiments were performed with the asymbiotic coral Dendrophyllia arbuscula and, to further assess if urea and/or nickel has an indirect link with calcification through photosynthesis, results were compared with those obtained with two symbiotic corals, Acropora muricata and Pocillopora damicornis, for which we also measured photosynthetic rates. Ambient and enriched nickel (0.12 and 3.50 µg L-1) combined with ambient and enriched urea concentrations (0.26 and 5.52 µmol L-1) were tested during 4 weeks in aquaria. We demonstrate in the study that a nickel enrichment alone or combined with a urea enrichment strongly stimulated urea uptake rates of the three tested species. In addition, this enhancement of urea uptake and hydrolysis significantly increased the long-term calcification rates (i.e. growth) of the three coral species investigated, inducing a 1.49-fold to 1.64-fold increase, respectively for D. arbuscula and P. damicornis. Since calcification was greatly enhanced by nickel in the asymbiotic coral species - i.e. in absence of photosynthesis - we concluded that the effect of increased urease activity on calcification was mainly direct. According to our results, it can be assumed that corals in some fringing reefs, benefiting from seawater enriched in nickel may have advantages and might be able to use urea more effectively as a carbon and nitrogen source. It can also be suggested that urea, for which hotspots are regularly measured in reef waters may alleviate the negative consequences of thermal stress on corals.


Assuntos
Antozoários/fisiologia , Calcificação Fisiológica/efeitos dos fármacos , Níquel/toxicidade , Urease/metabolismo , Análise de Variância , Animais , Antozoários/efeitos dos fármacos , Antozoários/crescimento & desenvolvimento , Processos Autotróficos/efeitos dos fármacos , Clorofila/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Processos Heterotróficos/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
4.
Ann Dermatol Venereol ; 145(5): 313-330, 2018 May.
Artigo em Francês | MEDLINE | ID: mdl-29678394

RESUMO

The development of immune checkpoint inhibitors (monoclonal antibodies targeting PD-1/PD-L1 or CTLA-4) represents a significant advance in the treatment of multiple cancers. Given their particular mechanism of action, which involves triggering CD4+/CD8+ T-cell activation and proliferation, they are associated with a specific safety profile. Their adverse events are primarily immune-related, and can affect practically all organs. In this context, dermatological toxicity is the most common, though it mostly remains mild to moderate and does not require discontinuation of treatment. More than a third of patients are faced with cutaneous adverse events, usually in the form of a maculopapular rash, pruritus or vitiligo (only in patients treated for melanoma). Much more specific dermatologic disorders, however, may occur such as lichenoid reactions, induced psoriasis, sarcoidosis, auto-immune diseases (bullous pemphigoid, dermatomyositis, alopecia areata), acne-like rash, xerostomia, etc. Rigorous dermatological evaluation is thus mandatory in the case of atypical, persistent/recurrent or severe lesions. In this article, we review the incidence and spectrum of dermatologic adverse events reported with immune checkpoint inhibitors. Finally, a management algorithm is proposed.


Assuntos
Antineoplásicos Imunológicos/efeitos adversos , Toxidermias/etiologia , Algoritmos , Antígeno CTLA-4/antagonistas & inibidores , Toxidermias/patologia , Humanos , Receptor de Morte Celular Programada 1/antagonistas & inibidores
5.
Proc Biol Sci ; 284(1847)2017 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-28100813

RESUMO

Reef coral calcification depends on regulation of pH in the internal calcifying fluid (CF) in which the coral skeleton forms. However, little is known about calcifying fluid pH (pHCF) regulation, despite its importance in determining the response of corals to ocean acidification. Here, we investigate pHCF in the coral Stylophora pistillata in seawater maintained at constant pH with manipulated carbonate chemistry to alter dissolved inorganic carbon (DIC) concentration, and therefore total alkalinity (AT). We also investigate the intracellular pH of calcifying cells, photosynthesis, respiration and calcification rates under the same conditions. Our results show that despite constant pH in the surrounding seawater, pHCF is sensitive to shifts in carbonate chemistry associated with changes in [DIC] and [AT], revealing that seawater pH is not the sole driver of pHCF Notably, when we synthesize our results with published data, we identify linear relationships of pHCF with the seawater [DIC]/[H+] ratio, [AT]/ [H+] ratio and [[Formula: see text]]. Our findings contribute new insights into the mechanisms determining the sensitivity of coral calcification to changes in seawater carbonate chemistry, which are needed for predicting effects of environmental change on coral reefs and for robust interpretations of isotopic palaeoenvironmental records in coral skeletons.


Assuntos
Antozoários/fisiologia , Calcificação Fisiológica , Carbonatos/química , Água do Mar/química , Animais , Recifes de Corais , Concentração de Íons de Hidrogênio
8.
PLoS One ; 10(10): e0139175, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26466126

RESUMO

Mucus, i.e., particulate and dissolved organic matter (POM, DOM) released by corals, acts as an important energy carrier in tropical ecosystems, but little is known on its ecological role in temperate environments. This study assessed POM and DOM production by the temperate coral Cladocora caespitosa under different environmental conditions. The subsequent enzymatic degradation, growth of prokaryotes and virus-like particles (VLPs) as well as changes in the structure of the prokaryotic communities were also monitored. C. caespitosa produced an important quantity of mucus, which varied according to the environmental conditions (from 37.8 to 67.75 nmol carbon h-1 cm-2), but remained higher or comparable to productions observed in tropical corals. It has an important nutritional value, as highlighted by the high content in dissolved nitrogen (50% to 90% of the organic matter released). Organic matter was rapidly degraded by prokaryotes' enzymatic activities, and due to its nitrogen content, aminopeptidase activity was 500 fold higher than the α-glucosidase activity. Prokaryotes, as well as VLPs, presented a rapid growth in the mucus, with prokaryote production rates as high as 0.31 µg h-1 L-1. Changes in bacterial and archaeal communities were observed in the ageing mucus and between mucus and the water column, suggesting a clear impact of mucus on microorganism diversity. Overall, our results show that the organic matter released by temperate corals, such as C. caespitosa, which can form reef structures in the Mediterranean Sea, stimulates microbial activity and thereby functions as a significant carbon and nitrogen supplier to the microbial loop.


Assuntos
Antozoários/metabolismo , Archaea/enzimologia , Bactérias/enzimologia , Glicosaminoglicanos/metabolismo , Consórcios Microbianos/fisiologia , Aminopeptidases/metabolismo , Animais , Antozoários/crescimento & desenvolvimento , Archaea/classificação , Archaea/crescimento & desenvolvimento , Proteínas Arqueais/metabolismo , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Proteínas de Bactérias/metabolismo , Carbono/metabolismo , Ciclo do Carbono/fisiologia , Recifes de Corais , Glicosaminoglicanos/biossíntese , Mar Mediterrâneo , Nitrogênio/metabolismo , Ciclo do Nitrogênio/fisiologia , Filogenia , Água do Mar , Simbiose/fisiologia , alfa-Glucosidases/metabolismo
9.
Photosynth Res ; 123(1): 95-104, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25255987

RESUMO

Gorgonians are one of the most important benthic components of tropical and temperate areas, and play a fundamental role as ecosystem engineers. Although global warming and pollution increasingly threaten them, the acquisition of nutrients, which is a key process in fitness and stress resistance, has been poorly investigated in such species. This study has thus used an advanced in situ incubation chamber for the first time with gorgonians, to assess the daily acquisition of nutrients and the photophysiology of the Mediterranean symbiotic species, Eunicella singularis. The xanthophyll cycle was assessed in parallel. This work has revealed that E. singularis presents a different functioning than the Mediterranean symbiotic corals. This gorgonian indeed relies on both autotrophy and heterotrophy in summer to optimize its energetic budget, while corals mainly shift to autotrophy for their respiratory needs and tissue growth. In addition, although E. singularis lives in the same depths/locations, and harbours the same symbiont genotype than the corals, the photosynthetic performances of their respective symbionts are significantly different. Indeed, E. singularis acquired 2-3 times less autotrophic carbon from its symbionts than corals, but maintained a positive carbon budget by reducing respiration rates, and by presenting maximal photosynthetic rates throughout the day, suggesting a very efficient light utilization. Almost no photoinhibition was observed under very high light levels, because of the induction of a xanthophyll photoprotection process. These results help understanding why gorgonians often dominate many benthic ecosystems.


Assuntos
Antozoários/fisiologia , Fotossíntese/fisiologia , Simbiose , Animais , Mar Mediterrâneo , Oxigênio/metabolismo , Temperatura , Xantofilas/fisiologia
11.
Br J Oral Maxillofac Surg ; 53(1): 49-53, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25305795

RESUMO

The standard of mandibular reconstruction has increased since the introduction of computer-assisted design (CAD) and rapid prototype modelling (RPM) for surgical planning. Between 2008 and 2013, a prospective pilot study of 20 patients was planned to compare the outcomes of patients treated by mandibular reconstruction who had CAD and RPM-guided operations using a precontoured titanium plate, with the outcomes of patients treated conventionally. We recorded the time taken for reconstruction, total operating time, and whether this type of planning could improve the results of mandibular reconstruction. We found significant differences in the incidence of dental malocclusion (p=0.03) and exposure of the titanium plate (p=0.009). The mean operating time for reconstruction in the preoperative planning group was 135 (37)min compared with 176 (58)min in the conventional group (p=0.04). Preoperative planning using CAD and RPM can increase the accuracy of microvascular mandibular reconstruction and reduce the operating time for reconstruction.


Assuntos
Materiais Biocompatíveis/química , Placas Ósseas , Transplante Ósseo/métodos , Desenho Assistido por Computador , Retalhos de Tecido Biológico/transplante , Reconstrução Mandibular/métodos , Microcirurgia/métodos , Planejamento de Assistência ao Paciente , Titânio/química , Adulto , Idoso , Feminino , Fíbula/transplante , Humanos , Imageamento Tridimensional/métodos , Masculino , Má Oclusão/etiologia , Reconstrução Mandibular/instrumentação , Pessoa de Meia-Idade , Duração da Cirurgia , Projetos Piloto , Complicações Pós-Operatórias , Estudos Prospectivos , Deiscência da Ferida Operatória/etiologia , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
12.
Br J Dermatol ; 171(1): 186-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24579866

RESUMO

Idiopathic CD4(+) lymphocytopenia (ICL) is a rare immunodeficiency syndrome of unknown origin for which the increased risks of opportunistic infections and of malignancies have been well established; however, skin dysimmune diseases, including psoriasis, have been scarcely reported up to now. We report herein the severe course of psoriasis in four patients with ICL, and show evidence for a defect in the skin recruitment of regulatory CD4(+) FoxP3(+) T cells. These data raise the apparent paradigm of the occurrence of a severe immunomediated disease together with a profound T-cell defect, a model that might also apply to other immune deficiencies associated with psoriasis.


Assuntos
Psoríase/etiologia , Linfócitos T Reguladores/imunologia , T-Linfocitopenia Idiopática CD4-Positiva/complicações , Adulto , Doença Crônica , Humanos , Masculino , Psoríase/imunologia
13.
Dermatology ; 226(4): 311-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23838298

RESUMO

We report the observation of cutaneous Kaposi's sarcoma (KS) worsening during the second trimester of pregnancy in 2 African women. Both patients were tested seronegative for HIV. They had no complication during their pregnancy, and no evidence of extracutaneous disease was found, allowing therapeutic abstention. They gave birth to healthy children showing no clinical evidence of human herpesvirus 8 (HHV-8) infection. Based on these observations and on the review of the literature, we discuss the risk of vertical transmission of HHV-8 as well as the impact of pregnancy on KS.


Assuntos
Infecções por Herpesviridae/transmissão , Transmissão Vertical de Doenças Infecciosas , Complicações Neoplásicas na Gravidez/patologia , Sarcoma de Kaposi/patologia , Neoplasias Cutâneas/patologia , Adulto , Progressão da Doença , Feminino , Infecções por Herpesviridae/virologia , Herpesvirus Humano 8 , Humanos , Nascido Vivo , Gravidez , Complicações Neoplásicas na Gravidez/virologia , Sarcoma de Kaposi/virologia , Neoplasias Cutâneas/virologia , Adulto Jovem
14.
Tissue Antigens ; 82(1): 68-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23745573

RESUMO

HLA-C*08:75 differs from C*08:02:01 by a non-synonymous mutation at codon 229 (GAG to AAG) in exon 4.


Assuntos
Alelos , Antígenos HLA-C/genética , População Branca/genética , Sequência de Bases , Éxons/genética , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência
15.
Tissue Antigens ; 82(1): 69-70, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23517135

RESUMO

HLA-C*08:76 differs from HLA-C*08:02:01 by one nonsynonymous nucleotide change at the codon 144 (CAG to AAG) in exon 3.


Assuntos
Alelos , Antígenos HLA-C/genética , População Branca/genética , Sequência de Bases , Éxons/genética , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência
16.
J Plast Reconstr Aesthet Surg ; 66(5): 617-22, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23419681

RESUMO

BACKGROUND: For the treatment of dermatofibrosarcoma protuberans (DFSP), wide surgical excision has been recommended, with 3-5-cm margins, including the first underlying clear fascia. Since 2006, a technical improvement in pathological analysis called the vertical modified technique (VMT) has allowed us to reduce the surgical margin without increased oncological risk. METHODS: Between 2006 and 2011, 66 cases of DFSP were analysed in our hospital, using VMT. We reviewed patient records, considering the initial margin, total margin, number of surgeries and outcomes. Functional and aesthetic consequences were assessed by the surgeon and by the patients. RESULTS: Mean initial margin for the first resection was 18 mm (10-30 mm). First resection allowed complete resection of the tumour in 52 cases (78.8%). Mean total surgical margin was 21.3 mm (10-60 mm). There were no cases of local tumour recurrence at a median follow-up of 30 months. Reconstruction was performed using direct sutures in 53 cases (80.3%), split-thickness skin grafts in six cases (9.1%), full-thickness skin grafts in five cases (7.6%) and flaps in two patients (3%). For 90.9% of the patients, the aesthetic result was acceptable, whereas 84.8% patients were satisfied with the functional result. CONCLUSION: VMT reduces surgical margins and allows for extensive analysis of margins. This technique represents a safe and reliable strategy in DFSP, without increasing the risk of recurrence. The outcomes of our study have confirmed the data from the literature regarding oncological safety.


Assuntos
Dermatofibrossarcoma/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Neoplasias Cutâneas/cirurgia , Retalhos Cirúrgicos , Adolescente , Adulto , Idoso , Criança , Dermatofibrossarcoma/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Cutâneas/patologia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
17.
Ann Dermatol Venereol ; 140(1): 52-5, 2013 Jan.
Artigo em Francês | MEDLINE | ID: mdl-23328361

RESUMO

BACKGROUND: Pigmented mammary tumours are rare. Herein, we report the third case of primary pigmented breast adenocarcinoma in a male patient with clinical mimicking of nodular melanoma of the nipple. PATIENTS AND METHODS: A male patient presented with a pigmented nodule of the right nipple. Histological examination of the lesion showed dermal and subcutaneous adenocarcinomatous proliferation. The perilesional stroma contained melanin both inside and outside macrophages, leading us to conclude on primary pigmented breast adenocarcinoma clinically mimicking nodular melanoma of the nipple. DISCUSSION: Local production of melanin by neoplastic cells in the mammary carcinoma was postulated as the cause of hyperpigmentation of the tumour. Other possible causes are transfer of melanin from overlying melanocytes of the pigmented areolar epidermis to the underlying neoplastic cells, or melanin synthesis by intratumoral melanocytes migrating from the epidermis (which strikes us as the most convincing interpretation for the reported case). CONCLUSION: Breast adenocarcinoma is a rare tumour in men and may present clinically as a pigmented lesion of the nipple, resulting in the problem of differential diagnosis with primary or metastasised nodular melanoma.


Assuntos
Adenocarcinoma/diagnóstico , Neoplasias da Mama Masculina/diagnóstico , Mamilos , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biópsia , Mama/patologia , Mama/cirurgia , Neoplasias da Mama Masculina/patologia , Neoplasias da Mama Masculina/cirurgia , Diagnóstico Diferencial , Humanos , Queratina-7/análise , Masculino , Melanoma/diagnóstico , Melanoma/patologia , Melanoma/cirurgia , Mamilos/patologia , Mamilos/cirurgia , Pele/patologia
19.
Mol Psychiatry ; 18(3): 382-93, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22751493

RESUMO

Smoking is the most important preventable cause of mortality and morbidity worldwide. This nicotine addiction is mediated through the nicotinic acetylcholine receptor (nAChR), expressed on most neurons, and also many other organs in the body. Even within the ventral tegmental area (VTA), the key brain area responsible for the reinforcing properties of all drugs of abuse, nicotine acts on several different cell types and afferents. Identifying the precise action of nicotine on this microcircuit, in vivo, is important to understand reinforcement, and finally to develop efficient smoking cessation treatments. We used a novel lentiviral system to re-express exclusively high-affinity nAChRs on either dopaminergic (DAergic) or γ-aminobutyric acid-releasing (GABAergic) neurons, or both, in the VTA. Using in vivo electrophysiology, we show that, contrary to widely accepted models, the activation of GABA neurons in the VTA plays a crucial role in the control of nicotine-elicited DAergic activity. Our results demonstrate that both positive and negative motivational values are transmitted through the dopamine (DA) neuron, but that the concerted activity of DA and GABA systems is necessary for the reinforcing actions of nicotine through burst firing of DA neurons. This work identifies the GABAergic interneuron as a potential target for smoking cessation drug development.


Assuntos
Neurônios Dopaminérgicos/fisiologia , Neurônios GABAérgicos/fisiologia , Interneurônios/fisiologia , Nicotina/farmacologia , Reforço Psicológico , Área Tegmentar Ventral/fisiologia , Potenciais de Ação/fisiologia , Animais , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios GABAérgicos/efeitos dos fármacos , Interneurônios/efeitos dos fármacos , Camundongos , Agonistas Nicotínicos/farmacologia , Receptores Nicotínicos/fisiologia , Área Tegmentar Ventral/efeitos dos fármacos
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