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1.
Angew Chem Int Ed Engl ; 61(37): e202206915, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35894267

RESUMO

The electrochemical oxygen reduction reaction (ORR) provides a green route for decentralized H2 O2 synthesis, where a structure-selectivity relationship is pivotal for the control of a highly selective and active two-electron pathway. Here, we report the fabrication of a boron and nitrogen co-doped turbostratic carbon catalyst with tunable B-N-C configurations (CNB-ZIL) by the assistance of a zwitterionic liquid (ZIL) for electrochemical hydrogen peroxide production. Combined spectroscopic analysis reveals a fine tailored B-N moiety in CNB-ZIL, where interfacial B-N species in a homogeneous distribution tend to segregate into hexagonal boron nitride domains at higher pyrolysis temperatures. Based on the experimental observations, a correlation between the interfacial B-N moieties and HO2 - selectivity is established. The CNB-ZIL electrocatalysts with optimal interfacial B-N moieties exhibit a high HO2 - selectivity with small overpotentials in alkaline media, giving a HO2 - yield of ≈1787 mmol gcatalyst -1 h-1 at -1.4 V in a flow-cell reactor.

2.
Environ Sci Technol ; 55(6): 3645-3656, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33617249

RESUMO

Hydrologic and irrigation regimes mediate the timing of selenium (Se) mobilization to rivers, but the extent to which patterns in Se uptake and trophic transfer through recipient food webs reflect the temporal variation in Se delivery is unknown. We investigated Se mobilization, partitioning, and trophic transfer along approximately 60 river miles of the selenium-impaired segment of the Lower Gunnison River (Colorado, USA) during six sampling trips between June 2015 and October 2016. We found temporal patterns in Se partitioning and trophic transfer to be independent of those in dissolved Se concentrations and that the recipient food web sustained elevated Se concentrations from earlier periods of high Se mobilization. Using an ecosystem-scale Se accumulation model tailored to the Lower Gunnison River, we predicted that the endangered Razorback Sucker (Xyrauchen texanus) and Colorado Pikeminnow (Ptychocheilus lucius) achieve whole-body Se concentrations exceeding aquatic life protection criteria during periods of high runoff and irrigation activity (April-August) that coincide with susceptible phases of reproduction and early-life development. The results of this study challenge assumptions about Se trophodynamics in fast-flowing waters and introduce important considerations for the management of Se risks for biota in river ecosystems.


Assuntos
Selênio , Poluentes Químicos da Água , Animais , Colorado , Ecossistema , Cadeia Alimentar , Rios , Selênio/análise , Poluentes Químicos da Água/análise
3.
Environ Sci Technol ; 54(15): 9228-9234, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32633495

RESUMO

Mercury (Hg) is a pervasive environmental pollutant and contaminant of concern for both people and wildlife that has been a focus of environmental remediation efforts for decades. A growing body of literature has motivated calls for revising Hg consumption advisories to co-consider selenium (Se) levels in seafood and implies that remediating aquatic ecosystems with ecosystem-scale Se additions could be a robust solution to Hg contamination. Provided that elevated Se concentrations are also known toxicological threats to aquatic animals, we performed a literature search to evaluate the strength of evidence supporting three assertions underpinning the ameliorating benefits of Se: (1) dietary Se reduces MeHg toxicity in consumers; (2) environmental Se reduces Hg bioaccumulation and biomagnification in aquatic food webs; and (3) Se inhibits Hg bioavailability to, and/or methylmercury production by, microbial communities. Limited or ambiguous support for each criterion indicates that many scientific uncertainties and gaps remain regarding Se mediation of Hg behavior and toxicity in abiotic and biotic compartments. Significantly more information is needed to provide a strong scientific basis for modifying current fish consumption advisories on the basis of Se:Hg ratios or for applying Se amendments to remediate Hg-contaminated ecosystems.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Selênio , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Peixes , Humanos , Mercúrio/análise , Selênio/análise , Poluentes Químicos da Água/análise
4.
Environ Sci Technol ; 53(8): 4119-4127, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30893998

RESUMO

Effluents from coal-fired power plant ash ponds are a major source of environmental contamination, annually loading more than a million metric tons of pollutants to aquatic ecosystems in the United States alone. Though this waste stream is characterized by elevated concentrations of numerous inorganic constituents, decades of previous research effort have focused on the ecotoxicological consequences of a single stressor: selenium. In this study, we compared concentrations of 10 trace elements among three North Carolina reservoirs with varying burdens following decades of coal combustion residual (CCR) inputs. Along this pollution gradient, we examined (1) environmental compartment-specific trace element enrichment relative to reference lake levels and (2) differences in CCR accumulation patterns among abiotic and biotic compartments. We report significant multivariate differences between CCR-receiving and reference lakes for surface water, pore water, sediment, and fish tissues as well as differences in CCR accumulation among North Carolina resident fish species. Multiple-element enrichment across receiving lake compartments additionally highlighted that CCR pollution is a mixtures contamination issue. Our results inform the ongoing discussion about effective regulation of impaired water bodies and identify important questions that might guide the monitoring of these systems as they recover.


Assuntos
Selênio , Poluentes Químicos da Água , Animais , Carvão Mineral , Cinza de Carvão , Ecossistema , Monitoramento Ambiental , Cadeia Alimentar , Lagos , North Carolina , Estados Unidos
5.
Support Care Cancer ; 27(10): 3869-3875, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30767130

RESUMO

The most common adverse event (AE) of dabrafenib and trametinib (DT) is pyrexia, which has been reported to occur in up to 71% of patients. Pyrexia resulted in therapy discontinuation in up to 26% of patients that otherwise were benefiting from the treatment. Little is known about the pathogenesis and optimal management of this common AE. We hypothesized that the etiology of pyrexia in patients treated with DT could be extrapolated from DT-related cutaneous adverse effects in which a paradoxical MAPK pathway activation has been identified. Based on preliminary data by our group suggesting an upregulation of the mitogen-activated protein kinases (MAPKs) in human lymphocytes exposed to dabrafenib and trametinib, specifically elevated expression of phosphorylated JNK (p-JNK), p38 MAPK (p-p38 MAPK), and ERK5 (p-ERK5), we hypothesized that the mechanism of MAPK pathway activation with DT therapy is similar to that reported in patients with familial Mediterranean fever (FMF), a rare, inherited condition characterized by episodes of fever and rash that responds exceedingly well to colchicine-based therapy in which the MAPK pathway is hyper-activated. Based on this association, our group explored the use of oral colchicine for the treatment of DT-associated pyrexia in five patients with metastatic melanoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Colchicina/uso terapêutico , Febre/induzido quimicamente , Febre/tratamento farmacológico , Imidazóis/efeitos adversos , Oximas/efeitos adversos , Piridonas/efeitos adversos , Pirimidinonas/efeitos adversos , Ativação Enzimática/efeitos dos fármacos , Humanos , Imidazóis/uso terapêutico , Masculino , Melanoma/tratamento farmacológico , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Oximas/uso terapêutico , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico
6.
J Urol ; 199(2): 393-400, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28941919

RESUMO

PURPOSE: We examined the incidence, characteristics and treatment of patients with tumor bed recurrence after partial nephrectomy. MATERIALS AND METHODS: We retrospectively reviewed the charts of 2,256 patients with sporadic small renal masses treated with partial nephrectomy between 2000 and 2014. Local tumor bed recurrence was strictly defined as detection of a new enhancing lesion 1) specifically in the surgical defect or 2) in the same region (eg lower pole) as the partial nephrectomy site. To determine differences in multiple characteristics 44 patients (1.9%) with local recurrence were compared to 163 randomly selected patients who underwent partial nephrectomy with no recurrence. RESULTS: Patients with local tumor bed recurrence were more likely to have a solitary kidney (27% vs 4%, p <0.01) and bilateral disease at presentation (23% vs 10.4%, p = 0.02) compared to the group with no recurrence. Positive margins were found in 15.9% of local tumor bed recurrences compared to 3% of the control group (p <0.01). Median time between partial nephrectomy and the detection of local tumor bed recurrence was 23 months (range 2 to 107). Male gender, a solitary kidney at partial nephrectomy, positive surgical margins, multiple tumors, and higher nephrometry score and pathological stage were associated with local tumor bed recurrence. CONCLUSIONS: Local tumor bed recurrence after partial nephrectomy is associated with several preoperative factors, including multiple tumors and a solitary kidney, as well as intraoperative and postoperative factors such as a positive surgical margin and higher pathological stage.


Assuntos
Carcinoma de Células Renais/cirurgia , Neoplasias Renais/cirurgia , Recidiva Local de Neoplasia , Nefrectomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/epidemiologia , Carcinoma de Células Renais/etiologia , Feminino , Seguimentos , Humanos , Incidência , Estimativa de Kaplan-Meier , Neoplasias Renais/diagnóstico , Neoplasias Renais/epidemiologia , Neoplasias Renais/etiologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/etiologia , Recidiva Local de Neoplasia/terapia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
7.
J Hered ; 109(5): 553-565, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29684146

RESUMO

The Sumatran rhinoceros (Dicerorhinus sumatrensis), once widespread across Southeast Asia, now consists of as few as 30 individuals within Sumatra and Borneo. To aid in conservation planning, we sequenced 218 bp of control region mitochondrial (mt) DNA, identifying 17 distinct mitochondrial haplotypes across modern (N = 13) and museum (N = 26) samples. Museum specimens from Laos and Myanmar had divergent mtDNA, consistent with the placement of western mainland rhinos into the distinct subspecies D. s. lasiotis (presumed extinct). Haplotypes from Bornean rhinos were highly diverse, but dissimilar from those of other regions, supporting the distinctiveness of the subspecies D. s. harrissoni. Rhinos from Sumatra and Peninsular Malaysia shared mtDNA haplotypes, consistent with their traditional placement into a single subspecies D. s sumatrensis. Modern samples of D. s. sumatrensis were genotyped at 18 microsatellite loci. Rhinos within Sumatra formed 2 sub-populations, likely separated by the Barisan Mountains, though with only modest genetic differentiation between them. There are so few remaining Sumatran rhinoceros that separate management strategies for subspecies or subpopulations may not be viable, while each surviving rhino pedigree is likely to retain alleles found in no other individuals. Given the low population size and low reproductive potential of Sumatran rhinos, rapid genetic erosion is inevitable, though an under-appreciated concern is the potential for fixation of harmful genetic variants. Both concerns underscore 2 overriding priorities for the species: 1) translocation of wild rhinos to ex situ facilities, and 2) collection and storage of gametes and cell lines from every surviving captive and wild individual.


Assuntos
Variação Genética , Perissodáctilos/genética , Animais , Conservação dos Recursos Naturais , DNA Mitocondrial/genética , Feminino , Haplótipos , Indonésia , Malásia , Masculino , Filogeografia
8.
Chemistry ; 23(49): 11810-11817, 2017 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-28471008

RESUMO

We report the synthesis of task-specific imidazolium ionic compounds and ionic liquids with key functionalities of organic molecules from electro-, polymer-, and coordination chemistry. Such products are highly functional and potentially suitable for technology applications even though they are formed without elaborate reactions and from cheap and potentially green reagents. We further demonstrate the versatility of the used synthetic approach by introducing different functional and green counterions to the formed ionic liquids directly during the synthesis or after metathesis reactions. The influence of different cation structures and different anions on the thermal and electrochemical properties of the resulting ionic liquids is discussed. Our goal is to make progress towards economically competitive and sustainable task-specific ionic liquids.

9.
Environ Sci Technol ; 51(4): 2418-2426, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28165723

RESUMO

Anthropogenic activities resulting in releases of selenium-laden waste streams threaten freshwater ecosystems. Lake ecosystems demand special consideration because they are characterized by prolonged retention of selenium and continuous cycling of the element through the food chain, through which it becomes available to toxicologically susceptible egg-laying vertebrates. This study documents the current selenium burden of lakes in North Carolina (NC) with historic selenium inputs from nearby coal-fired power plants. We measured selenium concentrations in surface waters, sediment pore waters, and resident fish species from coal combustion residual (CCR)-impacted lakes and paired reference lakes. The data are related to levels of recent selenium inputs and analyzed in the context of recently updated federal criteria for the protection of aquatic life. We show that the Se content of fish from lakes with the highest selenium inputs regularly exceed these criteria and are comparable to those measured during historic fish extirpation events in the United States. Large legacy depositions of CCRs within reservoir sediments are likely to sustain Se toxicity for many years despite recent laws to limit CCR discharge into surface waters in NC. Importantly, the widespread use of high-selenium coals for electricity generation extends the potential risk for aquatic ecosystem impacts beyond U.S. borders.


Assuntos
Lagos , Selênio , Animais , Carvão Mineral , Ecotoxicologia , North Carolina , Estados Unidos , Poluentes Químicos da Água
10.
Anim Biotechnol ; 28(2): 112-119, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-27791476

RESUMO

Toll-like receptor 2 (TLR2) plays an important role in recognition by the innate immune system of Gram-positive bacteria. As Gram-positive bacteria cause mastitis, we examined variations in the region of the TLR2 gene that codes for the extracellular domain. Samples of forty goats from a single dairy herd were collected, half with low SCC (≤200,000 cells/mL), and half with higher SCC. Two synonymous single nucleotide polymorphisms (SNPs) were identified: 840G > A and 1083A > G. One nonsynonymous SNP 739G > A was identified. This coded for valine or isoleucine, which have similar physiochemical properties, and was not in a region coding for a known functional domain. Surprisingly, the least square mean SCC of the heterozygous goats (146,220) was significantly lower than the SCC of homozygous GG goats (537,700; p = 0.004), although these two groups were similar in days in milk (p = 0.984), and there was no significant difference by breed (p = 0.941). Because factors other than mastitis can affect SCC and our sample sizes were limited, additional studies are needed to corroborate an association between TLR2 genotype and SCC or mastitis in goats.


Assuntos
Contagem de Células/veterinária , Cabras/genética , Cabras/metabolismo , Leite/citologia , Leite/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Receptor 2 Toll-Like/genética , Animais , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença/genética
11.
J Hered ; 105(1): 39-47, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24154534

RESUMO

Populations of North American river otters (Lontra canadensis) declined throughout large portions of the continent during the early 1900s due to habitat degradation and unregulated trapping. River otters had been extirpated in North Dakota (ND), but the Red River Valley has since been recolonized, with potential source populations including the neighboring states of Minnesota or South Dakota, or the Canadian province of Manitoba (MB). We genotyped 9 microsatellite loci in 121 samples to determine the source population of river otters in the Red River Valley of ND, as well as to assess population structure and diversity of river otters in central North America. Overall, genetic diversity was high, with an average observed heterozygosity of 0.58. Genetic differentiation was low (F ST < 0.05) between river otters in ND and those of Minnesota, suggesting that eastern ND was recolonized by river otters from Minnesota. River otters from MB were genetically distinct from all other sampled populations. Low genetic differentiation (F ST = 0.044) between South Dakota and Louisiana (LA) suggested that reintroductions using LA stock were successful. The genetic distinctiveness of river otters from different geographic regions should be considered when deciding on source populations for future translocations.


Assuntos
Variação Genética , Genética Populacional , Lontras/classificação , Lontras/genética , Animais , Ecossistema , Loci Gênicos , Desequilíbrio de Ligação , Repetições de Microssatélites/genética , América do Norte , Filogeografia , Rios
12.
Mod Rheumatol ; 24(4): 585-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24252008

RESUMO

OBJECTIVE: To analyze our five-year experience with a telephone helpline service for patients suffering from chronic rheumatic diseases and provide the patients' perspective derived from a dedicated survey. METHODS: A telephone service (contact center) was set up in the rheumatology unit at Sapienza University of Rome, Italy, in September 2007. It is managed by operators from a medical service society who collect the patients'calls. Daily reports with medical issues are transmitted to the physicians who are supposed to call back shortly. A year after the institution of the contact center, a questionnaire was administered to a group of patients to address the level of satisfaction. RESULTS: A total of 39,076 calls were registered between September 2007 and August 2012. Each month, an average of 20% of the calls were made by patients referring to our rheumatology unit for the first time and an average of 68.5% patients phoned to request medical consultation. Demographic analysis demonstrated a prevalence of middle-aged female patients. The majority of patients filling in the questionnaire declared an intention to use it again in the future. Furthermore, 85.7% of callers reported full satisfaction with respect to the responses received to their requests. CONCLUSIONS: A telephone helpline may provide extra-clinical advice and support for patients with rheumatic diseases. Although these services cannot replace clinical appointments, they should be encouraged both to assure patients easy access to medical counseling and to optimize the daily clinical workload of physicians.


Assuntos
Linhas Diretas , Pacientes Ambulatoriais , Satisfação do Paciente , Doenças Reumáticas/terapia , Reumatologia , Adulto , Gerenciamento Clínico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Artigo em Inglês | MEDLINE | ID: mdl-38888255

RESUMO

Despite decades of fate and effects studies, environmental selenium (Se) contamination and management remain an issue for many freshwater systems in North America. Several regulatory bodies have promulgated updated targets or management levels for Se; however, additional guidance on best practices for monitoring Se to protect freshwater aquatic life is warranted. In this article, we describe current approaches to assessing the ecological risks of Se in impaired freshwater systems and outline recommended methods for collecting and analyzing biological and abiotic samples and interpreting data. Because reproductive impairment of fish populations is most commonly used to determine the potential impacts of Se, several biological factors that could affect Se toxicity are explored, including diet, trophic positions, reproductive biology, body size and maturity, migratory movements, and use of seasonal habitats. Measuring Se concentrations in mature eggs is the most reliable metric for estimating potential reproductive impairment in fish populations because the range of toxicity thresholds is relatively narrow for all but a few tolerant fish species. In situations where collecting mature eggs is not feasible, we review the use of alternative fish tissue for estimating potential effects. Factors affecting Se uptake from freshwater are also considered with guidance on collecting abiotic (e.g., water and sediment) and biotic components of aquatic food webs (e.g., macroinvertebrates, biofilm). Integr Environ Assess Manag 2024;00:1-16. © 2024 SETAC.

14.
Behav Res Ther ; 173: 104457, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134498

RESUMO

Across social species, the presence of another individual can reduce stress reactions to adverse stimuli, a phenomenon known as social buffering. The present study investigated whether social buffering influences the expression and extinction of learned fear in adolescence, a developmental period of diminished fear inhibition and increased social interaction. Quality of maternal care and degree of social investigation were examined as factors that may influence social buffering. In adolescence, male rats were fear conditioned and then given extinction training either in the presence of a same-age rat or alone. Animals were then tested alone for extinction retention. In two experiments, the presence of a conspecific robustly reduced conditioned fear responses during extinction training. Interestingly, a persistent social buffering effect was observed when the extinction and conditioning contexts had prominent differences in features (Experiment 1), but not when these contexts were relatively similar (Experiment 2). Neither quality of maternal care nor degree of social investigation predicted the effects of social buffering. These findings suggest that social buffering robustly dampens fear responses during adolescence when a peer is present and this suppression can persist, in some instances, even when the peer is absent.


Assuntos
Extinção Psicológica , Comportamento Social , Humanos , Ratos , Masculino , Animais , Extinção Psicológica/fisiologia , Ratos Wistar , Medo/fisiologia , Condicionamento Clássico/fisiologia
15.
Am J Physiol Regul Integr Comp Physiol ; 304(4): R267-77, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23255589

RESUMO

Recent findings indicate that TLR3 polymorphisms increase susceptibility to enteroviral myocarditis and inflammatory dilated cardiomyopathy (iDCM) in patients. TLR3 signaling has been found to inhibit coxsackievirus B3 (CVB3) replication and acute myocarditis in mouse models, but its role in the progression from myocarditis to iDCM has not been previously investigated. In this study we found that TLR3 deficiency increased acute (P = 5.9 × 10(-9)) and chronic (P = 6.0 × 10(-7)) myocarditis compared with WT B6.129, a mouse strain that is resistant to chronic myocarditis and iDCM. Using left ventricular in vivo hemodynamic assessment, we found that TLR3-deficient mice developed progressively worse chronic cardiomyopathy. TLR3 deficiency significantly increased viral replication in the heart during acute myocarditis from day 3 through day 12 after infection, but infectious virus was not detected in the heart during chronic disease. TLR3 deficiency increased cytokines associated with a T helper (Th)2 response, including IL-4 (P = 0.03), IL-10 (P = 0.008), IL-13 (P = 0.002), and TGF-ß(1) (P = 0.005), and induced a shift to an immunoregulatory phenotype in the heart. However, IL-4-deficient mice had improved heart function during acute CVB3 myocarditis by echocardiography and in vivo hemodynamic assessment compared with wild-type mice, indicating that IL-4 impairs cardiac function during myocarditis. IL-4 deficiency increased regulatory T-cell and macrophage populations, including FoxP3(+) T cells (P = 0.005) and Tim-3(+) macrophages (P = 0.004). Thus, TLR3 prevents the progression from myocarditis to iDCM following CVB3 infection by reducing acute viral replication and IL-4 levels in the heart.


Assuntos
Cardiomiopatia Dilatada/virologia , Infecções por Coxsackievirus/imunologia , Enterovirus Humano B/fisiologia , Interleucina-4/imunologia , Miocardite/virologia , Receptor 3 Toll-Like/imunologia , Doença Aguda , Animais , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/imunologia , Doença Crônica , Infecções por Coxsackievirus/genética , Citocinas/biossíntese , Citocinas/imunologia , Modelos Animais de Doenças , Humanos , Interleucina-4/análise , Macrófagos/imunologia , Macrófagos/virologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Miocardite/genética , Miocardite/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/virologia , Receptor 3 Toll-Like/genética , Replicação Viral/imunologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-38041586

RESUMO

In the Lake Koocanusa-Kootenai River system (Montana, USA and British Columbia, Canada), selenium (Se) contamination has become an international concern and is suspected to contribute to the observed burbot (Lota lota) population collapse. Due to our limited ability to sample burbot in Lake Koocanusa for monitoring studies, we used a reference population to develop tools to model tissue Se disposition for a focal species in systems with elevated Se. Total Se concentrations in otoliths, biofluids (blood and endolymph), and tissues (muscle, liver, and ovary) from burbot in reference lakes in northwestern Ontario, Canada, were measured to document tissue-to-tissue Se relationships and evaluate the potential for otoliths to retrace Se exposure in fish. Among burbot tissue, Se concentrations were the highest in the ovary (mean ± SD = 4.55 ± 2.23 µg g-1 dry mass [dm]), followed by the liver (2.69 ± 1.96 µg g-1 dm) and muscle (1.87 ± 1.14 µg g-1 dm), and decreased with body size (p < 0.05). In otoliths, Se was detected at low levels (<1 µg g-1 ). Selenium concentrations in burbot samples were positively correlated among muscle, ovary, liver, and endolymph tissues, but not for the most recent annually averaged or lifetime-averaged Se concentrations in otoliths. We hypothesize that Se concentrations were too low in this study to establish links between otoliths and other fish tissues and to detect significant lifetime variation in individuals, and that further validation using archived otoliths from burbot exposed to elevated Se levels in Lake Koocanusa-Kootenai River is needed to reconstruct exposure histories. However, intercompartmental models proved valuable for estimating Se concentrations in burbot tissues only available by means of lethal sampling (i.e., ovary), although additional work should confirm whether the established models are reliable to predict concentrations in Se-impaired systems as tissue distributions are likely to differ with increasing Se levels. Integr Environ Assess Manag 2023;00:1-11. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

17.
Am J Physiol Heart Circ Physiol ; 302(8): H1726-36, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22328081

RESUMO

Myocarditis and dilated cardiomyopathy (DCM) are often caused by viral infections and occur more frequently in men than in women, but the reasons for the sex difference remain unclear. The aim of this study was to assess whether gene changes in the heart during coxsackievirus B3 (CVB3) myocarditis in male and female BALB/c mice predicted worse DCM in males. Although myocarditis (P = 4.2 × 10(-5)) and cardiac dilation (P = 0.008) were worse in males, there was no difference in viral replication in the heart. Fibrotic remodeling genes, such as tissue inhibitor of metalloproteinase (TIMP)-1 and serpin A 3n, were upregulated in males during myocarditis rather than during DCM. Using gonadectomy and testosterone replacement, we showed that testosterone increased cardiac TIMP-1 (P = 0.04), serpin A 3n (P = 0.007), and matrix metalloproteinase (MMP)-8 (P = 0.04) during myocarditis. Testosterone increased IL-1ß levels in the heart (P = 0.02), a cytokine known to regulate cardiovascular remodeling, and IL-1ß in turn increased cardiac serpin A 3n mRNA (P = 0.005). We found that 39 of 118 (33%) genes identified in acute DCM patients were significantly altered in the heart during CVB3 myocarditis in mice, including serpin A 3n (3.3-fold change, P = 0.0001). Recombinant serpin A 3n treatment induced cardiac fibrosis during CVB3 myocarditis (P = 0.0008) while decreasing MMP-3 (P = 0.04) and MMP-9 (P = 0.03) levels in the heart. Thus, serpin A 3n was identified as a gene associated with fibrotic cardiac remodeling and progression to DCM in male myocarditis patients and mice.


Assuntos
Proteínas de Fase Aguda/farmacologia , Infecções por Coxsackievirus/fisiopatologia , Interleucina-1beta/farmacologia , Miocardite/fisiopatologia , Serpinas/farmacologia , Testosterona/farmacologia , Remodelação Ventricular/efeitos dos fármacos , Proteínas de Fase Aguda/metabolismo , Animais , Doenças Autoimunes/fisiopatologia , Citocinas/metabolismo , Progressão da Doença , Feminino , Fibrose , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Análise em Microsséries , Dados de Sequência Molecular , Miocardite/genética , Miocardite/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Orquiectomia , Ovariectomia , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/farmacologia , Serpinas/metabolismo , Caracteres Sexuais , Remodelação Ventricular/fisiologia , Ensaio de Placa Viral
19.
Chem Commun (Camb) ; 58(31): 4841-4844, 2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35348156

RESUMO

The preparation of stable and efficient electrocatalysts comprising abundant and non-critical row-materials is of paramount importance for their industrial implementation. Herein, we present a simple synthetic route to prepare Mn(II) sub-nanometric active sites over a highly N-doped noble carbonaceous support. This support not only promotes a strong stabilization of the Mn(II) sites, improving its stability against oxidation, but also provides a convenient coordination environment in the Mn(II) sites able to produce CO, HCOOH and CH3COOH from electrochemical CO2 reduction.

20.
BMC Res Notes ; 14(1): 119, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33771210

RESUMO

OBJECTIVE: The Sumatran rhinoceros is critically endangered, with fewer than 100 individuals surviving across its current range. Accurate census estimates of the remaining populations are essential for development and implementation of conservation plans. In order to enable molecular censusing, we here develop microsatellite markers with amplicon sizes of short length, appropriate for non-invasive fecal sampling. RESULTS: Due to limited sample quantity and potential lack of genome-wide diversity, Illumina sequence reads were generated from two Sumatran rhinoceros samples. Genomic screening identified reads with short tandem repeats and loci that were polymorphic within the dataset. Twenty-nine novel polymorphic microsatellite markers were characterized (A = 2.4; HO = 0.30). These were sufficient to distinguish among individuals (PID < 0.0001), and to distinguish among siblings (PID(sib) < 0.0001). Among rhinos in Indonesia, almost all markers were established as polymorphic and effective for genotyping DNA from fecal samples. Notably, the markers amplified and displayed microsatellite polymorphisms using DNA extracted from 11 fecal samples collected non-invasively from wild Sumatran rhinoceros. These microsatellite markers provide an important resource for a census and genetic studies of wild Sumatran rhinos.


Assuntos
Repetições de Microssatélites , Perissodáctilos , Animais , Genoma , Genômica , Indonésia , Repetições de Microssatélites/genética , Perissodáctilos/genética
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