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1.
Environ Monit Assess ; 196(4): 333, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430282

RESUMO

The Doce River Basin (DRB) suffers with the adverse impacts of mining activities, due to its high level of urbanization and numerous industrial operations. In this study, we present novel insights into contaminant flow dynamics, seasonal variations, and the primary factors driving concentration levels within the region. We conducted an extensive analysis using a database sourced from the literature, which contained data on the contamination of arsenic (As) and lead (Pb) in the Doce River. Our primary aim was to investigate the patterns of As and Pb flow throughout the entire basin, their response to seasonal fluctuations, and the key parameters influencing their concentration levels. The results showed significant seasonal fluctuations in As and Pb fluxes, peaking during the rainy season. The 2015 Fundão dam breach in the DRB led to notable changes, elevating elemental concentrations, particularly As and Pb, which were subsequently transported to the Atlantic Ocean. These increased concentrations were primarily associated with iron and manganese oxides, hydroxides, and sulfates, rather than precipitation, as evidenced by regressions with low R2 values for both As (R2 = 0.07) and Pb (R2 < 0.001), concerning precipitation. The PCA analysis further supports the connection between these elements and the oxides and hydroxides of Fe and Mn. The approach employed in this study has proven to be highly effective in comprehending biogeochemical phenomena by leveraging data from the literature and could be a model for optimizing resources by capitalizing on existing information to provide valuable insights for drainage basin management, particularly during crises.


Assuntos
Arsênio , Estações do Ano , Rios , Chumbo , Monitoramento Ambiental , Óxidos , Hidróxidos
2.
Environ Monit Assess ; 195(7): 911, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37392279

RESUMO

The importance of environmental quality for global social and ecological development, including soil degradation, cannot be overstated. Trace elements dispersed in the environment due to anthropogenic or geogenic activities can result in ecotoxicological impacts, negatively influencing environmental quality. The reference values for soil quality concerning trace elements are primarily based on geological, geomorphological, and pedological patterns. However, intrinsic geological factors may diverge some concentration levels from established norms. Therefore, conducting comprehensive surveys of environmental quality reference values becomes imperative, incorporating geological, geomorphological, and pedological patterns. A deeper understanding of the distribution of these elements is also required. Multivariate analysis proves crucial in compartmentalizing the most relevant factors, particularly in regions marked by bimodal magmatism arising from post-collisional distensional processes, such as the Santa Angélica intrusive suite in southeast Brazil. This study collected soil samples from pastures and natural grasslands with minimal anthropogenic intervention at two depths. These samples underwent various chemical and physical analyses. Statistical techniques such as correlation analysis, principal component analysis, hierarchical clustering, and geostatistics were utilized to interpret the data. The analysis revealed a correlation between the clay fraction and trace elements, demonstrating that clustering is an effective methodology for ascertaining landscape distribution patterns of these components. When compared to quality reference values, it was observed that most soil content levels exceeded both global and local standards. This study suggests that the presence of barium (Ba) in the soil might be due to the isomorphic replacement of feldspathic minerals in acidic and intermediate rocks, whereas molybdenum (Mo) seems to be associated with soils in the domain of porphyritic allanite granite. However, additional research is warranted to determine the concentration factor of Mo in this scenario accurately.


Assuntos
Solo , Oligoelementos , Monitoramento Ambiental , Argila , Molibdênio
3.
Ann Surg Oncol ; 27(8): 2906-2912, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32266572

RESUMO

BACKGROUND: Sentinel lymph node (SLN) biopsy is the standard care for early detection and staging of lymph node metastasis in melanomas. Radiocolloids (RC) and blue dyes are used for SLN detection. Recently, near infrared (NIR) fluorescence tracing using indocyanine green has been developed as an alternative method for SLN detection. The relatively high tissue penetration depth of several millimeters and the ability to detect low concentrations of tracer both suggest that NIR may have significant advantages over RC and the blue dye methods. The objective of this study was to prospectively compare the performance of all three SLN detection techniques using them sequentially to evaluate the same group of patients. METHODS: One hundred twenty-one primary cutaneous melanoma patients with an indication for SLN biopsy were assigned to the procedure following NIR, blue dye, and RC detection techniques. RESULTS: No adverse event was reported. SLN was not detected in only 4.1% of cases. In 90.9%, an SLN was identified with NIR, but without any auxiliary technique in only 70.2% of cases. RC detected the SLN in 92.6% of cases. Patent blue was found in the sentinel node in 76.9%. The combination of all three techniques detected an SLN in 95.9% of cases. Metastases were present in 26.7%. The false-negative rate was 8.8%, with a negative predictive value of 91.2%. CONCLUSIONS: RC was the only technique with high SLN detection. Both the blue dye and NIR methods added sensitivity to the detection rate but should not be a substitute for RC.


Assuntos
Melanoma , Linfonodo Sentinela , Neoplasias Cutâneas , Corantes , Humanos , Verde de Indocianina , Linfonodos/diagnóstico por imagem , Linfocintigrafia , Melanoma/diagnóstico por imagem , Melanoma/cirurgia , Estudos Prospectivos , Linfonodo Sentinela/diagnóstico por imagem , Linfonodo Sentinela/cirurgia , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/cirurgia
4.
Cytokine ; 129: 155025, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32044670

RESUMO

Interferon (IFN) plays a central role in regulating host immune response to viral pathogens through the induction of IFN-Stimulated Genes (ISGs). IFN also enhances cellular SUMOylation and ISGylation, though the functional interplay between these modifications remains unclear. Here, we used a system-level approach to profile global changes in protein abundance in SUMO3-expressing cells stimulated by IFNα. These analyses revealed the stabilization of several ISG factors including SAMHD1, MxB, GBP1, GBP5, Tetherin/BST2 and members of IFITM, IFIT and IFI families. This process was correlated with enhanced IFNα-induced anti-HIV-1 and HSV-1 activities. Also IFNα upregulated protein ISGylation through increased abundance of E2 conjugating enzyme UBE2L6, and E3 ISG15 ligases TRIM25 and HERC5. Remarkably, TRIM25 depletion blocked SUMO3-dependent protein stabilization in response to IFNα. Our data identify a new mechanism by which SUMO3 regulates ISG product stability and reinforces the relevance of the SUMO pathway in controlling both the expression and functions of the restriction factors and IFN antiviral response.


Assuntos
Interferon-alfa/farmacologia , Sumoilação/efeitos dos fármacos , Antivirais/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Expressão Gênica/efeitos dos fármacos , Células HEK293 , Células HeLa , Humanos , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinas/metabolismo
5.
Arch Environ Contam Toxicol ; 79(3): 343-353, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33057758

RESUMO

Accidents involving economic activities of great impact, such as mining, have caused massive environmental damage. In November 2015, the dam of Fundão, located in the city of Mariana, MG, broke and released 5 × 107 m3 of tailings in the nearby ecosystems, including the Doce River. The physicochemical changes that occurred in the Doce River estuary were analyzed, as well as the trace metal concentrations, both 1 day before and 1 month after the disaster. The analyses of the collected samples (water and sediment) showed changes to the physicochemistry regarding dissolved oxygen, SPM, and temperature (p = 0.008, 0.001, 0.036, respectively). It also detected metals (Fe and Al) in the dissolved fraction beyond the limits recommended by the Brazilian legislation. There was an increase in the total concentrations of Fe and Cd in the sediment after the rupture of the dam and a change in mobile metals (Al, Cd, Cr, Cu, Fe, Ni, Pb, and Zn), with higher concentrations of mobile metals being found closer to the ocean (p = 0.06356). After the rupture of the dam, there was a change in the granulometric fraction of the sediment, which became composed mainly of silt and clay. All of the results showed a change on the Doce River estuary, caused by the arrival of the tailings, which can result in future harmful effects with the release of metals present in the sediment and adsorbed to the particles. The changes to the sediment, such as changes in the granulometric fraction, can have negative consequences for the benthic community.


Assuntos
Monitoramento Ambiental/métodos , Estuários , Sedimentos Geológicos/química , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , Brasil , Desastres , Ecossistema , Mineração , Oligoelementos/análise
6.
J Med Virol ; 90(3): 599-603, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29064575

RESUMO

To identify decoy cells, cytological examination was performed in urine cytospin slides. Decoy cells are related to Polyomaviruses (JC virus [JCV] and BK virus [BKV]), which are recognized worldwide due to potential infection and morbidity in kidney transplant recipients. Cytologically, it is difficult to evaluate the cytopathic effect of JCV and BKV in urine of patients with urothelial neoplasia. For this reason, there is a need for molecular approaches. To evaluate the incidence of BKV and JCV DNA in archival slides of urine cytospin material with benign and malignant characteristics. A total of 176 urine specimens were used for cytological examination of neoplastic or decoy cells. The samples were analyzed for the presence of JCV and BKV, by polymerase chain reaction (PCR) in DNA Isolated from archival slides of urine cytospin material. A typical samples (n = 48) were compared with the remaining 128 samples without atypia/neoplasia for the presence of JCV or BKV DNA. A statistically nonsignificant result was observed correlating the presence of JCV or BKV. The results show that DNA Isolated from archival slides of urine cytospin material can be used for detection of BKV and JCV.


Assuntos
Vírus BK/isolamento & purificação , Bancos de Espécimes Biológicos , Técnicas Citológicas/instrumentação , DNA Viral/urina , Vírus JC/isolamento & purificação , Urotélio/virologia , Vírus BK/genética , Técnicas Citológicas/métodos , DNA Viral/isolamento & purificação , Genoma Viral , Humanos , Incidência , Vírus JC/genética , Transplante de Rim , Neoplasias/virologia , Reação em Cadeia da Polimerase , Infecções por Polyomavirus/diagnóstico , Infecções Tumorais por Vírus/diagnóstico , Urotélio/patologia
7.
Transpl Infect Dis ; 20(4): e12901, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29668077

RESUMO

BACKGROUND: Although identifying cytological viral inclusions (decoy cells) in the urine is relatively easy, distinguishing between Polyomaviruses BKV and JCV is not possible. Few studies have been published regarding JCV detection in kidney transplant recipients. OBJECTIVE: To evaluate the incidence of BKV and JCV DNA in archival slides of urine cytospin material from renal transplant patients. METHODS: A total of 44 urine specimens were evaluated cytologically for the presence of viral inclusions (decoy cells) and by nested polymerase chain reaction to differentiate between JCV and BKV in DNA isolated from archival slides of urine cytospin material. RESULTS: Of the 44 urine specimen donors, 9 (20.5%) patients had at least 1 sample with alterations suggestive of or compatible with viral infection (decoy cells), and 3 had urine samples with cellular atypias/neoplasias. Additionally, 24/44 (54.5%) patients had PCR-positive DNA for Polyomavirus in at least 1 sample, including 11/44 who were positive for BKV (25%) and 16/44 who were positive for JCV (36.36%), with 3 (6.8%) patients showing viral coinfection. Regarding transplantation time, only JCV was statistically significant (P = .019) for periods longer than 10 years. CONCLUSIONS: The results highlight the potential use of archival slides of urine cytospin material to differentiate BKV and JCV and demonstrate the importance of improved JCV detection for later kidney transplant recipients.


Assuntos
Vírus BK/isolamento & purificação , Vírus JC/isolamento & purificação , Transplante de Rim/efeitos adversos , Infecções por Polyomavirus/epidemiologia , Infecções Tumorais por Vírus/epidemiologia , Vírus BK/genética , DNA Viral/isolamento & purificação , Feminino , Humanos , Incidência , Vírus JC/genética , Masculino , Reação em Cadeia da Polimerase , Infecções por Polyomavirus/urina , Infecções por Polyomavirus/virologia , Infecções Tumorais por Vírus/urina , Infecções Tumorais por Vírus/virologia
8.
Exp Cell Res ; 330(1): 151-63, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25447205

RESUMO

Mx proteins are evolutionarily conserved dynamin-like large GTPases involved in viral resistance triggered by types I and III interferons. The human MxA is a cytoplasmic protein that confers resistance to a large number of viruses. The MxA protein is also known to self-assembly into high molecular weight homo-oligomers. Using a yeast two-hybrid screen, we identified 27 MxA binding partners, some of which are related to the SUMOylation machinery. The interaction of MxA with Small-Ubiquitin MOdifier 1 (SUMO1) and Ubiquitin conjugating enzyme 9 (Ubc9) was confirmed by co-immunoprecipitation and co-localization by confocal microscopy. We identified one SUMO conjugation site at lysine 48 and two putative SUMO interacting motifs (SIMa and SIMb). We showed that MxA interacts with the EIL loop of SUMO1 in a SIM-independent manner via its CID-GED domain. The yeast two-hybrid mapping also revealed that Ubc9 binds to the MxA GTPase domain. Mutation in the putative SIMa and SIMb, which are located in the GTPase binding domain, reduced MxA antiviral activity. In addition, we showed that MxA can be conjugated to SUMO2 or SUMO3 at lysine 48 and that the SUMOylation-deficient mutant of MxA (MxAK48R) retained its capacity to oligomerize and to inhibit Vesicular Stomatitis Virus (VSV) and Influenza A Virus replication, suggesting that MxA SUMOylation is not essential for its antiviral activity.


Assuntos
Proteínas de Resistência a Myxovirus/metabolismo , Sumoilação , Motivos de Aminoácidos , Animais , Sítios de Ligação , Células HeLa , Humanos , Camundongos , Proteínas de Resistência a Myxovirus/química , Células NIH 3T3 , Ligação Proteica , Proteína SUMO-1/química , Proteína SUMO-1/metabolismo , Enzimas de Conjugação de Ubiquitina/química , Enzimas de Conjugação de Ubiquitina/metabolismo
9.
Mar Pollut Bull ; 200: 116076, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301435

RESUMO

The Guiana dolphin (Sotalia guianensis) is categorized as vulnerable in the Brazilian list of endangered animals, and its populations suffer from several anthropological threats. In this study, we analyzed the presence of macro, meso, and microplastics (MPs) in Guiana dolphins (n = 12) in Brazil Southeastern coast by analysing their gastrointestinal tract. The MP extractions were carried out with H2O2 (35 %) to remove organic matter. Four specimens ingested meso and macroplastics, including an item of polypropylene of 19.22 cm that was produced about 943 km from the place in which the animal was found stranded. All the specimens analyzed had fragment-type microplastics in their intestines. Blue was the prevailing color, followed by black, green, and red. We highlight the contamination by microplastics in the species, still little investigated, especially the need to understand the contamination by microplastics along trophic levels.


Assuntos
Golfinhos , Animais , Brasil , Peróxido de Hidrogênio , Microplásticos , Plásticos , Trato Gastrointestinal
10.
Hum Cell ; 37(4): 1170-1183, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38565739

RESUMO

Cutaneous squamous cell carcinoma (cSCC) is a common type of skin cancer that can result in significant morbidity, although it is usually well-managed and rarely metastasizes. However, the lack of commercially available cSCC cell lines hinders our understanding of this disease. This study aims to establish and characterize a new metastatic cSCC cell line derived from a Brazilian patient. A tumor biopsy was taken from a metastatic cSCC patient, immortalized, and named HCB-541 after several passages. The cytokeratin expression profile, karyotypic alterations, mutational analysis, mRNA and protein differential expression, tumorigenic capacity in xenograft models, and drug sensitivity were analyzed. The HCB-541 cell line showed a doubling time between 20 and 30 h and high tumorigenic capacity in the xenograft mouse model. The HCB-541 cell line showed hypodiploid and hypotetraploidy populations. We found pathogenic mutations in TP53 p.(Arg248Leu), HRAS (Gln61His) and TERT promoter (C228T) and high-level microsatellite instability (MSI-H) in both tumor and cell line. We observed 37 cancer-related genes differentially expressed when compared with HACAT control cells. The HCB-541 cells exhibited high phosphorylated levels of EGFR, AXL, Tie, FGFR, and ROR2, and high sensitivity to cisplatin, carboplatin, and EGFR inhibitors. Our study successfully established HCB-541, a new cSCC cell line that could be useful as a valuable biological model for understanding the biology and therapy of metastatic skin cancer.


Assuntos
Carcinoma de Células Escamosas , Mutação , Neoplasias Cutâneas , Humanos , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Telomerase/genética , Telomerase/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Camundongos
11.
Environ Monit Assess ; 185(4): 3117-31, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22821322

RESUMO

The Ethiopian Rift Valley Lakes host populations of edible fish species including Oreochromis niloticus, Labeobarbus intermedius and Clarias gariepinus, which are harvested also in other tropical countries. We investigated the occurrence of six heavy metals in tissues of these fish species as well as in the waters of Lake Koka and Lake Awassa. Both lakes are affected by industrial effluents in their catchments, making them ideal study sites. Mercury concentrations were very low in the water samples, but concentrations in the fish samples were relatively high, suggesting a particularly high bioaccumulation tendency as compared with the other investigated metals. Mercury was preferentially accumulated in the fish liver or muscle. It was the only metal with species-specific accumulation with highest levels found in the predatory species L. intermedius. Lower mercury concentrations in O. niloticus could be attributed to the lower trophic level, whereas mercury values in the predatory C. gariepinus were unexpectedly low. This probably relates to the high growth rate of this species resulting in biodilution of mercury. Accumulation of lead, selenium, chromium, arsenic and cadmium did not differ between species, indicating that these elements are not biomagnified in the food chain. Values of cadmium, selenium and arsenic were highest in fish livers, while lead and chromium levels were highest in the gills, which could be related to the uptake pathway. A significant impact of the industrial discharges on the occurrence of metals in the lakes could not be detected, and the respective concentrations in fish do not pose a public health hazard.


Assuntos
Monitoramento Ambiental , Peixes/metabolismo , Lagos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , Etiópia , Metais Pesados/metabolismo , Medição de Risco , Poluentes Químicos da Água/metabolismo , Poluição Química da Água/estatística & dados numéricos
12.
Sci Total Environ ; 863: 160934, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36539082

RESUMO

Microplastic (MP) pollution is a global problem and has affected several biological levels even in protected areas. In the present study, MP contamination was investigated in fish associated with sandy beaches in a permanent environmental protection area in the Amazon. In order to achieve this goal, the shape, color, abundance, richness, and chemical composition of MPs in the digestive tract of 29 fish species in 24 beaches of the Machado River, western Brazilian Amazon, were evaluated. Linear mixed models (LMMs) were adjusted to test the effects of local human modification (HMc), distance from urban settlements, distance from the closest affluent, and trophic categories of fish species on microplastic abundance and richness in their digestive tracts. From the 1082 fish analyzed, 332 (30 %) presented MPs in their digestive tracts. A total of 617 MPs was found (1.8 ± 1.6 MPs; 4.5 ± 1.9 MPs/g fish). Omnivorous and insectivorous fish presented more MPs in sandy beaches located closer to urban settlements. However, carnivorous fish presented a higher abundance of MPs in their digestive tracts compared with the other trophic guilds. This is the first study to analyze plastic contamination in fish associated with sandy beaches in the Amazon (Brazil), and it revealed contamination of the ichthyofauna mainly related to the distance from urban settlements. Our results reinforce the need for better management of landscape surrounding protected areas to mitigate MP pollution.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Humanos , Plásticos , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Peixes
13.
Environ Sci Pollut Res Int ; 30(11): 31383-31394, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36447105

RESUMO

In this study, total Hg concentrations (HgT) were determined in the suspended particulate matter (SPM) and the dissolved fraction of the water column to evaluate their behavior through a gradient of physical-chemical parameters in a continuum between rivers and the Serinhaém River estuary of the Pratigi Environmental Protection Area, a pristine environment without point sources of Hg contamination, located in Northeast Brazil. Twelve points were sampled, forming a river-estuary transect, and two samplings were carried out (April and September 2019). Significant spatial and temporal effects were detected only for particulate HgT and not for dissolved HgT. Considering both samplings, the mean HgT concentrations in SPM were 1112 ± 824 and 44 ± 33 ng·g-1 in the river and estuary, respectively. Also, HgT concentrations in the dissolved fraction (1.61 ± 0.61 ng·L-1) were below the limits established by environmental agencies (CONAMA = 2 µg∙L-1 and USEPA = 1.4 µg·L-1). Salinity and SPM concentrations were important predictors of HgT in the water column (R2 = 0.81, p < 0.0001; R2 = 0.56, p < 0.0001, respectively). Mercury transport to the ocean through SPM was 2 kg∙year-1, 4000 times greater than the dissolved fraction.


Assuntos
Mercúrio , Poluentes Químicos da Água , Água do Mar , Água , Brasil , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Mercúrio/análise , Rios , Estuários , Material Particulado/análise
14.
Mar Pollut Bull ; 195: 115447, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37716129

RESUMO

This study analyzed the concentrations of 15 (Al, As, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, V, Zn) toxicologically important trace elements in the livers of 110 green turtles stranded in two areas of the Brazilian coast. These areas are essential for the refuge, feeding, and reproduction of the species, and the information obtained is intended to support the development of conservation strategies. Higher concentrations were observed in the Região dos Lagos, RJ in almost all elements, except for Al, Mo, Pb, and V. This location showed statistically higher differences in the concentrations of Cd (4.66 ± 2.33 µg.g-1), Fe (846.62 ± 583.06 µg.g-1), and Zn (27.17 ± 10.90 µg.g-1). The differences in trace element concentration patterns between the two study areas are likely influenced by multiple factors, including the bioavailability of trace elements, oceanic upwelling events, anthropogenic activities, habitat characteristics, and organism-specific metabolic processes.

15.
Mar Pollut Bull ; 188: 114653, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36764148

RESUMO

In the present study a mass balance calculation was used to quantify trace elements (Al, Ba, Cd, Cr, Cu, Fe, Mn, Pb, Ti, V and Zn) fluxes exported from the Serinhaém River estuary to the Atlantic Ocean. The studied elements exportation in the particulate fraction showed higher fluxes in the first sampling campaign and a high export rate to the Atlantic Ocean during this period. The physical-chemical parameters showed the highest values in sampling campaign 1. These variations are probably the cause of the different trace elements behavior in fluvial and estuarine areas, where removal and addition processes between particulate and dissolved phases took place, affecting distribution coefficient and fluxes to the Atlantic Ocean. EPA ecosystems present values in accordance with Brazilian legislation for pristine areas, however, monitoring programs must be carried out in the region, to avoid future environmental problems.


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Rios , Estações do Ano , Estuários , Oligoelementos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Ecossistema , Metais Pesados/análise
16.
Photochem Photobiol Sci ; 11(7): 1201-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22441459

RESUMO

The influence of ring size on the photobehaviour of condensed 1,4-naphthoquinone systems, such as pyrano- and furano-derivatives (1 and 2, respectively) has been investigated. The absorption spectra for both families of naphthoquinones reveal clear differences; in the case of 2 they extend to longer wavelengths. A solvatochromic red shift in polar solvents is consistent with the π,π* character of the S(0)→ S(1) electronic transition in all cases. Theoretical (B3LYP) analysis of the HOMO and LUMO Kohn-Sham molecular orbitals of the S(0) state indicates that they are π and π* in nature, consistent with the experimental observation. A systematic study on the efficiency of singlet oxygen generation by these 1,4-naphthoquinones is presented, and values larger than 0.7 were found in every case. In accordance with these results, laser flash photolysis of deoxygenated acetonitrile solutions led to the formation of detectable triplet transient species with absorptions at 390 and 450 nm (1) and at 370 nm (2), with φ(ISC) close to 1. Additionally, the calculated energies for the T(1) states relative to the S(0) states at UB3LYP/6-311++G** are ca. 47 kcal mol(-1) for 1 and 43 kcal mol(-1) for 2. A comparison of the geometrical parameters for the S(0) and T(1) states reveals a marked difference with respect to the arrangement of the exocyclic phenyl ring whilst a comparison of electronic parameters revealed the change from a quinone structure to a di-dehydroquinone diradical structure.


Assuntos
Naftoquinonas/química , Oxigênio Singlete/química , Acetonitrilas/química , Lasers , Naftoquinonas/efeitos da radiação , Fotólise , Teoria Quântica , Solventes/química
17.
Mar Pollut Bull ; 162: 111821, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33162056

RESUMO

This study analyzed trace elements (As, Ba, Cd, Cu, Fe, Mn, Pb, Zn) and stable isotopes of carbon and nitrogen in egg yolk samples of female green turtles that nested in Rocas Atoll, Brazil, in 2017 and 2018. The trace elements concentration varied between years, with higher concentrations in 2017, suggesting that the nesting groups come from different foraging sites. The isotopic data indicated high overlap between years (73%), leading to an ambiguous interpretation on the turtles' foraging site. The Normalized Total Load presented a low association (0.01 < R2 < 0.41) with the stable isotopes. The Normalized Total Load that represents the trace element load in egg yolk is a holistic approach that can be applied elsewhere to predict ecotoxicology pathways in any animal species. We recommend a continuous monitoring to verify how the trace elements load behave in the nesting green turtles on Rocas Atoll.


Assuntos
Oligoelementos , Tartarugas , Poluentes Químicos da Água , Animais , Brasil , Gema de Ovo , Feminino , Isótopos , Oligoelementos/análise , Poluentes Químicos da Água/análise
18.
Mar Pollut Bull ; 163: 111953, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33418344

RESUMO

The Serinhaém River estuary is located in the Environmental Protection Area (EPA) of Pratigi, in the State of Bahia, Brazil, which is recognized for being a relatively well-preserved environment. In this work, the levels of aluminum (Al), arsenic (As), barium (Ba), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), vanadium (V), and zinc (Zn) were determined to evaluate the behavior of these chemical elements through geochemical parameters. Eighty-one sediment samples were collected in five sediment cores along the estuarine region. The results of the composition of the Serinhaém river basin showed high levels of Fe, Al, and Mn in the sediment samples. By using Principal Component Analysis, it was observed that 55.8% of the elements have a significant correlation with Fe, Al, and Mn, which may have the same origin or be associated with Fe and Mn oxy-hydroxides, and aluminosilicates. Although Cr, As, and V are correlated with Fe, Mn, and Al, their concentrations are above those established by NOAA, suggesting adverse effects on biota. Barium concentrations increased toward the outfall, where it meets the Camamu Bay, which is naturally enriched with this element. It was also possible to observe that along with the vertical profile, there were no variations in the concentrations of the elements, while along the estuary, it was possible to verify that the cores differ from each other. The estuary of the Serinhaém River can be considered to be influenced relatively little by human activities, and its concentrations can be considered as a base level for this coastal region.


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Brasil , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Humanos , Metais Pesados/análise , Rios , Poluentes Químicos da Água/análise
19.
Pancreas ; 50(6): 815-821, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34347723

RESUMO

OBJECTIVES: Rapid on-site evaluation (ROSE) by cytopathologists during endoscopic ultrasound-fine-needle aspiration (EUS-FNA) of solid pancreatic lesions (SPLs) improves adequacy and diagnostic accuracy while reducing the number of needle passes. We evaluated the usefulness of ROSE performed by the endosonographer. METHODS: Patients with an SPL were randomly assigned to EUS-FNA with ROSE or non-ROSE. Procedure duration, number of needle passes, specimen adequacy, and adverse event rates were compared. RESULTS: Sixty-five patients were enrolled (33 in the ROSE vs 32 in the non-ROSE group). Both groups were similar in terms of age, sex, size, and location of the lesion. Specimen adequacy rates were high and similar between groups. Mean (standard deviation) procedure duration was shorter in the ROSE versus non-ROSE group (30.0 [11.3] vs 37.0 [7.2] minutes, P < 0.005), as well as the mean (standard deviation) number of needle passes (2.6 [0.8] vs 3.5 [0.8], P < 0.005). Accuracy parameters as sensitivity and accuracy of ROSE by the endosonographer for malignancy were 93% and 88%, respectively. CONCLUSIONS: After specific training, the endosonographer can accurately evaluate samples during EUS-FNA of SPL, allowing for a shorter procedure duration and a lower number of needle passes.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Endossonografia/métodos , Pâncreas/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Avaliação Rápida no Local , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
20.
J Immunother Cancer ; 9(7)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34315822

RESUMO

A commentary on the original research article: 'Radiomics analysis for predicting pembrolizumab response in patients with advanced rare cancers'. Of note, the predictor selection process, the cross-validation method, along with the lack of final testing of the developed model with a separated data set may mask overfitting, overestimating performance metrics.


Assuntos
Anticorpos Monoclonais Humanizados , Neoplasias , Anticorpos Monoclonais Humanizados/uso terapêutico , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
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