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BACKGROUND: Most of large epidemiological studies on melanoma susceptibility have been conducted on fair skinned individuals (US, Australia and Northern Europe), while Southern European populations, characterized by high UV exposure and dark-skinned individuals, are underrepresented. OBJECTIVES: We report a comprehensive pooled analysis of established high- and intermediate-penetrance genetic variants and clinical characteristics of Mediterranean melanoma families from the MelaNostrum Consortium. METHODS: Pooled epidemiological, clinical and genetic (CDKN2A, CDK4, ACD, BAP1, POT1, TERT, and TERF2IP and MC1R genes) retrospective data of melanoma families, collected within the MelaNostrum Consortium in Greece, Italy and Spain, were analysed. Univariate methods and multivariate logistic regression models were used to evaluate the association of variants with characteristics of families and of affected and unaffected family members. Subgroup analysis was performed for each country. RESULTS: We included 839 families (1365 affected members and 2123 unaffected individuals). Pathogenic/likely pathogenic CDKN2A variants were identified in 13.8% of families. The strongest predictors of melanoma were ≥2 multiple primary melanoma cases (OR 8.1; 95% CI 3.3-19.7), >3 affected members (OR 2.6; 95% CI 1.3-5.2) and occurrence of pancreatic cancer (OR 4.8; 95% CI 2.4-9.4) in the family (AUC 0.76, 95% CI 0.71-0.82). We observed low frequency variants in POT1 (3.8%), TERF2IP (2.5%), ACD (0.8%) and BAP1 (0.3%). MC1R common variants (≥2 variants and ≥2 RHC variants) were associated with melanoma risk (OR 1.4; 95% CI 1.0-2.0 and OR 4.3; 95% CI 1.2-14.6, respectively). CONCLUSIONS: Variants in known high-penetrance genes explain nearly 20% of melanoma familial aggregation in Mediterranean areas. CDKN2A melanoma predictors were identified with potential clinical relevance for cancer risk assessment.
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Melanoma , Neoplasias Cutâneas , Humanos , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/genética , Estudos Retrospectivos , Mutação , Predisposição Genética para Doença , Melanoma/epidemiologia , Melanoma/genética , Melanoma/patologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Mutação em Linhagem Germinativa , Receptor Tipo 1 de Melanocortina/genéticaRESUMO
BACKGROUND: A polygenic inheritance involving high, medium and low penetrance genes has been suggested for melanoma susceptibility in adults, but genetic information is scarce for paediatric patients. OBJECTIVE: We aim to analyse the major high and intermediate melanoma risk genes, CDKN2A, CDK4, POT1, MITF and MC1R, in a large multicentre cohort of Italian children and adolescents in order to explore the genetic context of paediatric melanoma and to reveal potential differences in heritability between children and adolescents. METHODS: One-hundred-twenty-three patients (<21 years) from nine Italian centres were analysed for the CDKN2A, CDK4, POT1, MITF, and MC1R melanoma predisposing genes. The rate of gene variants was compared between sporadic, familial and multiple melanoma patients and between children and adolescents, and their association with clinico-pathological characteristics was evaluated. RESULTS: Most patients carried MC1R variants (67%), while CDKN2A pathogenic variants were found in 9% of the cases, the MITF E318K in 2% of patients and none carried CDK4 or the POT1 S270N pathogenic variant. Sporadic melanoma patients significantly differed from familial and multiple cases for the young age at diagnosis, infrequent red hair colour, low number of nevi, low frequency of CDKN2A pathogenic variants and of the MC1R R160W variant. Melanoma in children (≤12 years) had more frequently spitzoid histotype, were located on the head/neck and upper limbs and had higher Breslow thickness. The MC1R V92M variant was more common in children than in adolescents. CDKN2A common polymorphisms and MC1R variants were associated with a high number of nevi. CONCLUSION: Our results confirm the scarce involvement of the major high-risk susceptibility genes in paediatric melanoma and suggest the implication of MC1R gene variants especially in the children population.
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Melanoma , Neoplasias Cutâneas , Adolescente , Adulto , Criança , Genes p16 , Predisposição Genética para Doença , Humanos , Melanoma/genética , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/genéticaRESUMO
AIMS: This study aimed to evaluate in vitro individual and combined antifungal activity of propolis extract (PE) and oregano essential oil (OEO) against Penicillium allii, causal agent of blue mould disease. The chemical characterization of both products was also included. METHODS AND RESULTS: Chromatographic analysis of PE and OEO confirmed the presence of bioactive compounds. The antifungal susceptibility assays showed that PE and OEO were highly active against the mycelial growth and conidial germination of P. allii. PE and OEO MICs were 12·5 and 1·5 µl ml-1 , respectively. The MFCs of these products were 50 and 3·1 µl ml-1 , respectively. PE acted mainly through diffusion, while OEO acted by a mixed contribution of vapour and diffusion. Synergism and additive effect between both products were found in some combination ratios. CONCLUSION: PE and OEO, both natural products with different chemical composition, have a strong antifungal activity against P. allii and show a favourable interaction causing synergism. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study indicated the potential use of PE combined with OEO as a non-conventional strategy towards the formulation of a biofungicide to control blue mould disease in garlic seed-cloves.
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Ascomicetos , Alho , Óleos Voláteis , Origanum , Penicillium , Própole , Syzygium , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Própole/farmacologia , SementesRESUMO
BACKGROUND: Brodalumab was efficacious and safe in moderate-to-severe plaque-type psoriasis in the AMAGINE trials; published reports under real-life conditions are limited. OBJECTIVES: To evaluate the effectiveness and safety of brodalumab in patients with moderate-to-severe plaque-type psoriasis in a real-world setting. METHODS: This observational, retrospective study enrolled adult patients (≥18 years) with moderate-to-severe plaque-type psoriasis who underwent 24 weeks of treatment with brodalumab at 17 Italian dermatological centres. Baseline data included demographics, comorbidities, age of onset and duration of psoriasis and previous treatments. Psoriasis Area and Severity Index (PASI), Physician Global Assessment (PGA), static PGA of Genitalia, Dermatology Life Quality Index and patient satisfaction were assessed at weeks 0, 4, 12 and 24; adverse events were recorded. RESULTS: Seventy-eight patients (mean age 47.9 years, 71.8% male, average disease duration 16.8 years) were enrolled. A rapid and significant reduction in mean PASI score was observed after 4 weeks of treatment, decreasing further at weeks 12 and 24 (all P < 0.0001 vs. baseline). A higher number of cardiometabolic comorbidities and previous therapies were negatively associated with the achievement of PASI 90 at all assessments. Brodalumab was effective in bio-experienced patients, including those who had failed on anti-interleukin (IL)-17 therapies. Quality of life and patient satisfaction increased significantly during treatment (P < 0.0001 and P < 0.01 vs. baseline, respectively). Treatment was interrupted in 9 (11.5%) patients due to adverse events (n = 4), lack of efficacy (n = 3), lost to follow-up (n = 1) and surgical procedure (n = 1). CONCLUSIONS: Brodalumab is effective and safe in the treatment of moderate-to-severe psoriasis in a real-world setting, including in patients with failure to anti-IL17 therapies.
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Psoríase , Qualidade de Vida , Adulto , Anticorpos Monoclonais , Anticorpos Monoclonais Humanizados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/tratamento farmacológico , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
We propose a practical alternative to Eliashberg equations for the ab initio calculation of superconducting transition temperatures and gap functions. Within the recent density functional theory for superconductors, we develop an exchange-correlation functional that retains the accuracy of Migdal's approximation to the many-body electron-phonon self-energy, while having a simple analytic form. Our functional is based on a parametrization of the Eliashberg self-energy for a superconductor with a single Einstein frequency, and enables density functional calculations of experimental excitation gaps. By merging electronic structure methods and Eliashberg theory, the present approach sets a new standard in quality and computational feasibility for the prediction of superconducting properties.
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Cutaneous squamous cell carcinoma (cSCC) represents 20% of all skin cancers. Although primary cSCCs can be successfully treated with surgery, a subset of highly aggressive lesions may progress to advanced disease, representing a public healthcare problem with significant cancer-related morbidity and mortality. A complex network of genes (TP53, CDKN2A, NOTCH1 and NOTCH2, EGFR and TERT) and molecular pathways (RAS/RAF/MEK/ERK and PI3K/AKT/mTOR) have been shown to play an important role in the pathogenesis of cSCC. The epigenetic regulation of TP53 and CDKN2A is an attractive therapeutic target for the treatment of cSCC, as well as NOTCH-activating agents capable to restore its tumour-suppressor function. EGFR inhibitors including both monoclonal antibodies (cetuximab and panitumumab) and tyrosine kinase inhibitors (erlotinib, gefitinib and dasatinib) have been used in clinical trials for the treatment of advanced cSCC, achieving only partial clinical benefit. Recently, an immune-modulatory drug (cemiplimab) has been introduced for the treatment of advanced cSCC with good clinical results and a favourable safety profile, while other PD1/PD-L1 inhibitors, either as monotherapy or in combination with targeted therapies, are currently under investigation. This review focuses on molecular findings involved in the pathogenesis of cSCC and their implications for the future development of new treatment strategies. In addition, current and ongoing treatments on targeted therapies and/or immunotherapy are illustrated.
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Carcinoma de Células Escamosas , Neoplasias Cutâneas , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Epigênese Genética , Humanos , Biologia Molecular , Fosfatidilinositol 3-Quinases , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genéticaRESUMO
Adenosine represents a powerful modulating factor, which has been shown to orchestrate the scope, duration, and remission of the inflammatory response through the activation of four specific receptors, classified as A1, A2A, A2B, and A3, all being widely expressed in a variety of immune cells. Several selective A2A receptor agonists have displayed anti-inflammatory effects, through the suppression of IL-12, TNF, and IFN-γ production by monocytes and lymphocytes, in the setting of chronic intestinal inflammation. However, the therapeutic application of A2A receptor agonists remains hindered by the risk of serious cardiovascular adverse effects arising from the wide systemic distribution of A2A receptors. The present study focused on evaluating the anti-inflammatory effects of the novel poorly absorbed A2A receptor agonist PSB-0777 in a rat model of oxazolone-induced colitis as well as to evaluate its cardiovascular adverse effects, paying particular attention to the onset of hypotension, one of the main adverse effects associated with the systemic pharmacological activation of A2A receptors. Colitis was associated with decreased body weight, an enhanced microscopic damage score and increased levels of colonic myeloperoxidase (MPO). PSB-0777, but not dexamethasone, improved body weight. PSB-0777 and dexamethasone ameliorated microscopic indexes of inflammation and reduced MPO levels. The beneficial effects of PSB-0777 on inflammatory parameters were prevented by the pharmacological blockade of A2A receptors. No adverse cardiovascular events were observed upon PSB-0777 administration. The novel A2A receptor agonist PSB-0777 could represent the base for the development of innovative pharmacological entities able to act in an event-specific and site-specific manner.
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Agonistas do Receptor A2 de Adenosina/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Colite/patologia , Colo/efeitos dos fármacos , Furanos/farmacologia , Adjuvantes Imunológicos/toxicidade , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Colite/induzido quimicamente , Modelos Animais de Doenças , Furanos/administração & dosagem , Furanos/química , Masculino , Oxazolona/toxicidade , Ratos , Ratos Sprague-DawleyRESUMO
Nutcracker esophagus (NE), Jackhammer esophagus (JHE), distal esophageal spasm (DES), and hypertensive lower esophageal sphincter (HTLES) are defined by esophageal manometric findings. Some patients with these esophageal motility disorders also have abnormal gastroesophageal reflux. It is unclear to what extent these patients' symptoms are caused by the motility disorder, the acid reflux, or both. The aim of this study was to determine the effectiveness of laparoscopic Nissen fundoplication (LNF) on esophageal motility disorders, gastroesophageal reflux, and patient symptoms. Between 2007 and 2013, we performed high-resolution esophageal manometry on 3400 patients, and 221 patients were found to have a spastic esophageal motility disorder. The medical records of these patients were reviewed to determine the manometric abnormality, presence of gastroesophageal symptoms, and amount of esophageal acid exposure. In those patients that underwent LNF, we compared pre- and postoperative esophageal motility, gastroesophageal symptom severity, and esophageal acid exposure. Of the 221 patients with spastic motility disorders, 77 had NE, 2 had JHE, 30 had DES, and 112 had HTLES. The most frequently reported primary and secondary symptoms among all patients were: heartburn and/or regurgitation, 69.2%; respiratory, 39.8%; dysphagia, 35.7%; and chest pain, 22.6%. Of the 221 patients, 192 underwent 24-hour pH monitoring, and 103 demonstrated abnormal distal esophageal acid exposure. Abnormal 24-hour pH monitoring was detected in 62% of patients with heartburn and regurgitation, 49% of patients with respiratory symptoms, 36.8 % of patients with dysphagia, and 32.6% of patients with chest pain. Sixty-six of the 103 patients with abnormal 24-hour pH monitoring underwent LNF. Thirty-eight (13NE, 2JHE, 6 DES, and 17 HTLES) of these 66 patients had a minimum of 6-month postoperative follow-up that included clinical evaluation, esophageal manometry, and 24-hour pH monitoring. Postoperatively, all 38 patients had normal distal esophageal acid exposure. Of these 38 patients, symptoms resolved in 28 and improved in 10. Of six patients (one with NE, two JHE, and three with HTLES) that underwent postoperative esophageal manometry, five exhibited normal motility. Typical reflux symptoms are common among patients with esophageal hypermotility disorders. Abnormal 24-hour pH monitoring is present in the majority of patients with who report typical reflux symptoms and almost half of patients who report respiratory symptoms. Conversely, the majority of patients who report dysphagia or chest pain have normal distal esophageal acid exposure. Based on a small number of patients in this study, it also appears that motility disorders often improve after LNF. LNF is associated with resolution or improvement in reflux related symptoms and esophageal motility parameters in patients exhibiting abnormal esophageal acid exposure. This suggests that patient symptoms are due to abnormal acid exposure and not the motility disorder.
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Transtornos da Motilidade Esofágica/cirurgia , Fundoplicatura/métodos , Refluxo Gastroesofágico/complicações , Laparoscopia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/fisiopatologia , Transtornos da Motilidade Esofágica/complicações , Transtornos da Motilidade Esofágica/fisiopatologia , Monitoramento do pH Esofágico , Esôfago/fisiopatologia , Esôfago/cirurgia , Feminino , Refluxo Gastroesofágico/fisiopatologia , Azia/etiologia , Azia/fisiopatologia , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
Collagen VI is a non-fibrillar collagen present in the extracellular matrix (ECM) as a complex polymer; the mainly expressed form is composed of α1, α2 and α3 chains; mutations in genes encoding these chains cause myopathies known as Ullrich congenital muscular dystrophy (UCMD), Bethlem myopathy (BM) and myosclerosis myopathy (MM). The collagen VI α6 chain is a recently identified component of the ECM of the human skeletal muscle. Here we report that the α6 chain was dramatically reduced in skeletal muscle and muscle cell cultures of genetically characterized UCMD, BM and MM patients, independently of the clinical phenotype, the gene involved and the effect of the mutation on the expression of the "classical" α1α2α3 heterotrimer. By contrast, the collagen VI α6 chain was normally expressed or increased in the muscle of patients affected by other forms of muscular dystrophy, the overexpression matching with areas of increased fibrosis. In vitro treatment with TGF-ß1, a potent collagen inducer, promoted the collagen VI α6 chain deposition in the ECM of normal muscle cells, whereas, in cultures derived from collagen VI-related myopathy patients, the collagen VI α6 chain failed to develop a network outside the cells and accumulated in the endoplasmic reticulum. The defect of the α6 chain points to a contribution to the pathogenesis of collagen VI-related disorders.
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Colágeno Tipo VI/metabolismo , Contratura/metabolismo , Músculo Esquelético/metabolismo , Distrofias Musculares/congênito , Distrofias Musculares/metabolismo , Esclerose/metabolismo , Adolescente , Adulto , Western Blotting , Células Cultivadas , Criança , Pré-Escolar , Colágeno Tipo VI/genética , Contratura/genética , Contratura/patologia , Matriz Extracelular/metabolismo , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Distrofias Musculares/genética , Distrofias Musculares/patologia , Mutação/genética , Fenótipo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esclerose/genética , Esclerose/patologia , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Adulto JovemRESUMO
INTRODUCTION: Daylight photodynamic therapy (DL-PDT) with methyl aminolevulinate (MAL) is a simplified PDT procedure that was recently shown in a few trials to be effective for grade I actinic keratosis (AK), with improved tolerability and reduced time of clinical attendance as compared to conventional PDT (c-PDT). OBJECTIVE: To evaluate the efficacy and tolerability of DL-PDT vs. c-PDT with MAL in the treatment of grade I AK on the face and scalp in Italy. METHODS: Thirty-five patients with AKs on the face (n = 17) or scalp (n = 18) were prospectively enrolled in an intra-patient, left-right, prospective, comparison study between DL-PDT and c-PDT at a single centre between September and October 2013. Weather conditions and outdoor temperature during daylight exposure were recorded for each DL-PDT session. Pain was assessed after the PDT session and local adverse events 2 days after treatment. Lesion response rate was evaluated on both sides at 3 months. AKs with complete regression were followed until 6 months. Patient's preference for either treatment was recorded. RESULTS: There was no difference in complete response (CR) rate of AK I at 3 months between DL-PDT and c-PDT (87% vs. 91%; RR = 0.96; P = 0.16). A lower CR rate was observed with DL-PDT than with c-PDT for AK II (36% vs. 61%; RR = 0.58, P = 0.06) and III (25% vs. 46%; RR = 0.50, P = 0.20). Recurrence rate at 6 months was slightly higher for cleared AK I after DL-PDT than after c-PDT (17% vs. 12%, RR = 1.50, P < 0.05). DL-PDT was associated with lower pain (ΔVAS = -2.2, P < 0.01) and reduced severity of local adverse events (ΔLSR = -1.4, P < 0.01) than c-PDT. Increasing outdoor temperature was associated with the efficacy of DL-PDT and the severity of adverse events. DL-PDT was preferred by 88% of the patients. CONCLUSION: MAL DL-PDT showed similar efficacy to c-PDT in the treatment of AK I of the face/scalp but was less effective than c-PDT for AKs II and III. DL-PDT was better tolerated being associated with lower pain and occurrence of fewer adverse events. Clinical response to DL-PDT was significantly moderated by outdoor temperature, increasing at higher temperatures.
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Dermatoses Faciais/tratamento farmacológico , Ceratose Actínica/tratamento farmacológico , Fotoquimioterapia/métodos , Dermatoses do Couro Cabeludo/tratamento farmacológico , Luz Solar , Idoso , Idoso de 80 Anos ou mais , Ácido Aminolevulínico/análogos & derivados , Ácido Aminolevulínico/uso terapêutico , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Medição da Dor , Satisfação do Paciente , Fotoquimioterapia/efeitos adversos , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Prospectivos , Recidiva , Creme para a Pele , Protetores Solares/administração & dosagem , TemperaturaRESUMO
BACKGROUND: Several algorithms are available for the dermoscopic diagnosis of pigmented skin lesions. The MC1R gene is a key determinant of pigmentation characteristics that are established host-related melanoma risk factors. OBJECTIVES: To investigate the association of dermoscopic features of sporadic cutaneous melanomas with clinical characteristics of patients and corresponding tumours and with genetic changes in the MC1R and BRAF genes. METHODS: A total of 64 dermoscopic images of 62 patients were scored by ABCD rule and modified pattern analysis. Detailed patients' and melanomas' characteristics were collected. Patients were screened for germline MC1R variants and related melanomas for somatic V600 BRAF mutations. RESULTS: A lower total dermoscopic score (TDS) was observed in melanomas of patients with red hair (P = 0.019), due to reduced dermoscopic structures (P < 0.0001). Thicker melanomas showed higher TDS values (P = 0.021) due to sharper borders (P < 0.0001) and higher number of colors (P = 0.004). An atypical pigment network was prevalent in superficial spreading melanomas (P = 0.010), in individuals with dark skin (P = 0.043) and hair color (P = 0.001). An atypical vascular pattern was more frequent in nodular (P < 0.0001) and thick (P < 0.0001) melanomas, in individuals with skin type I-II (P = 0.037), blond or red hair color (P = 0.032) and blue or green eyes (P = 0.014). Melanomas of MC1R R carriers showed lower TDS value (P = 0.037), reduced dermoscopic structures (P = 0.001) and lower prevalence of atypical pigment network (P = 0.001). No differences were identified between BRAF-mutated or wild-type melanomas. CONCLUSIONS: We suggest a phenotypic/MC1R profile for melanoma patients and their tumours. Melanomas of MC1R R carriers show a significant lower TDS value, with reduced dermoscopic structures, and a lower prevalence of an atypical pigment network. Non-carriers of MC1R R variants develop melanomas dermoscopically characterized by an atypical pigment network which is prevalent in superficial spreading melanomas, in patients with dark complexion and less frequent in red-haired individuals.
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Dermoscopia , Melanoma/patologia , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/patologia , Feminino , Humanos , Masculino , Melanoma/genética , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genéticaRESUMO
We show that the spectral properties of a self-amplified spontaneous emission x-ray free-electron laser can be controlled by modulating the gain in magnetic undulators, thus producing one or several spectral lines within a single few femtosecond pulse. By varying the magnetic field along the undulator and the electron beam transport line, the system we demonstrate can tailor the x-ray spectrum to optimally meet numerous experimental requirements for multicolor operation.
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Síndrome de Birt-Hogg-Dubé/complicações , Melanoma/complicações , Neoplasias Cutâneas/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Síndrome de Birt-Hogg-Dubé/genética , Criança , Feminino , Filaminas/genética , Humanos , Masculino , Melanoma/genética , Pessoa de Meia-Idade , Mutação/genética , Neoplasias Cutâneas/genética , Adulto Jovem , Melanoma Maligno CutâneoRESUMO
Deltas are the locus of river-borne sediment accumulation, however, their role in sequestering plastic pollutants is still overlooked. By combining geomorphological, sedimentological, and geochemical analyses, which include time-lapse multibeam bathymetry, sediment provenance, and µFT-IR analyses, we investigate the fate of plastic particles after a river flood event providing an unprecedented documentation of the spatial distribution of sediment as well as of microplastics (MPs), including particles fibers, and phthalates (PAEs) abundances in the subaqueous delta. Overall sediments are characterized by an average of 139.7 ± 80 MPs/kg d.w., but display spatial heterogeneity of sediment and MPs accumulation: MPs are absent within the active sandy delta lobe, reflecting dilution by clastic sediment (ca. 1.3 Mm3) and sediment bypass. The highest MP concentration (625 MPs/kg d.w.) occurs in the distal reaches of the active lobe where flow energy dissipates. In addition to MPs, cellulosic fibers are relevant (of up to 3800 fibers/kg d.w.) in all the analyzed sediment samples, and dominate (94 %) with respect to synthetic polymers. Statistically significant differences in the relative concentration of fiber fragments ≤0.5 mm in size were highlighted between the active delta lobe and the migrating bedforms in the prodelta. Fibers were found to slightly follow a power law size distribution coherent with a one-dimensional fragmentation model and thus indicating the absence of a size dependent selection mechanism during burial. Multivariate statistical analysis suggests traveling distance and bottom-transport regime as the most relevant factors controlling particle distribution. Our findings suggest that subaqueous prodelta should be considered hot spots for the accumulation of MPs and associated pollutants, albeit the strong lateral heterogeneity in their abundances reflects changes in the relative influence of fluvial and marine processes.
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X-ray free-electron lasers (XFELs) deliver intense x-ray pulses that destroy the sample in a single shot by a Coulomb explosion. Experiments using XFEL pulse trains or the new generation of high-repetition rate XFELs require rapid sample replacement beyond those provided by the systems now used at low repletion-rate XFELs. We describe the development and characterization of a system based on a spinning disk to continuously deliver a solid sample into an XFEL interaction point at very high speeds. We tested our system at the Linac Coherent Light Source and European XFEL hard x-ray nano-focus instruments, employing it to deliver a 25 µm copper foil sample, which can be used as a gain medium for stimulated x-ray emission for the proposed x-ray laser oscillator.
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Collagen VI myopathies (Ullrich congenital muscular dystrophy (UCMD), Bethlem myopathy (BM), and myosclerosis myopathy) share a common pathogenesis, that is, mitochondrial dysfunction due to deregulation of the permeability transition pore (PTP). This effect was first identified in the Col6a1(-/-) mouse model and then in muscle cell cultures from UCMD and BM patients; the normalizing effect of cyclosporin A (CsA) confirmed the pathogenic role of PTP opening. In order to determine whether mitochondrial performance can be used as a criterion for inclusion in clinical trials and as an outcome measure of the patient response to therapy, it is mandatory to establish whether mitochondrial dysfunction is conserved in primary cell cultures from UCMD and BM patients. In this study we report evidence that mitochondrial dysfunction and the consequent increase of apoptotic rate can be detected not only, as previously reported, in muscle, but also in fibroblast cell cultures established from muscle biopsies of collagen VI-related myopathic patients. However, the mitochondrial phenotype is no longer maintained after nine passages in culture. These data demonstrate that the dire consequences of mitochondrial dysfunction are not limited to myogenic cells, and that this parameter can be used as a suitable diagnostic criterion, provided that the cell culture conditions are carefully established.