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1.
Mol Cell ; 83(19): 3421-3437.e11, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37751740

RESUMO

The nuclear receptor co-repressor (NCoR) complex mediates transcriptional repression dependent on histone deacetylation by histone deacetylase 3 (HDAC3) as a component of the complex. Unexpectedly, we found that signaling by the receptor activator of nuclear factor κB (RANK) converts the NCoR/HDAC3 co-repressor complex to a co-activator of AP-1 and NF-κB target genes that are required for mouse osteoclast differentiation. Accordingly, the dominant function of NCoR/HDAC3 complexes in response to RANK signaling is to activate, rather than repress, gene expression. Mechanistically, RANK signaling promotes RNA-dependent interaction of the transcriptional co-activator PGC1ß with the NCoR/HDAC3 complex, resulting in the activation of PGC1ß and inhibition of HDAC3 activity for acetylated histone H3. Non-coding RNAs Dancr and Rnu12, which are associated with altered human bone homeostasis, promote NCoR/HDAC3 complex assembly and are necessary for RANKL-induced osteoclast differentiation in vitro. These findings may be prototypic for signal-dependent functions of NCoR in other biological contexts.


Assuntos
Osteoclastos , RNA , Humanos , Camundongos , Animais , Proteínas Correpressoras/genética , Osteoclastos/metabolismo , Ligante RANK/genética , Correpressor 1 de Receptor Nuclear/genética , Correpressor 1 de Receptor Nuclear/metabolismo , Expressão Gênica
2.
J Anal At Spectrom ; 38(5): 1135-1145, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37180679

RESUMO

One widely utilised method to reduce spectral interferences for measurements using inductively coupled plasma mass spectrometry (ICP-MS) is to employ the use of a reaction cell gas. Nitrous oxide (N2O) is a highly reactive gas typically used for mass-shifting only target analytes to a higher mass-to-charge ratio with increased sensitivity (e.g. +16, +32, +48 amu for monoxide, dioxide, and trioxide product ions respectively). Traditionally, the use of N2O was limited to selected applications due to the creation of new interferences that also interfere with the detected masses of interest. However, with the advent of inductively coupled plasma tandem mass spectrometry (ICP-MS/MS), the use of N2O has gained more traction, with a growing number of publications in recent years. Here, a comprehensive study of the use of N2O for the determination of 73 elements has been conducted, with a comparison to the most widely used mass-shift method using oxygen (O2) as a reaction gas. In total, 59 elements showed improved sensitivity when performing mass-shift with N2O compared to O2, with 8 elements showing no reaction with either gas. Additionally, N2O demonstrated a collisional focusing effect for 36 elements when measuring on-mass. This effect was not observed using O2. Monitoring asymmetric charge transfer reactions with N2O highlighted 14 elements, primarily non-metals and semi-metals, that enter the gas cell as metastable ions and could be used as an alternative mass-shift option. The results from this study highlight the high versatility of N2O as a reaction cell gas for routine ICP-MS/MS measurements.

3.
Anal Chim Acta ; 1212: 339910, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35623784

RESUMO

Visualization and quantification of corrosion processes is essential in materials research. Here we present a new approach for 2D spatiotemporal imaging of metal corrosion dynamics in situ. The approach combines time-integrated Mg2+ flux imaging by diffusive gradients in thin films laser ablation inductively coupled plasma mass spectrometry (DGT LA-ICP-MS) and near real-time pH imaging by planar optodes. The parallel assessment of Mg2+ flux and pH distributions on a fine-structured, bare Mg alloy (b-WE43) showed intense Mg dissolution with Mg2+ flux maxima up to 11.9 ng cm-2 s-1 and pH increase >9 during initial corrosion (≤15 min) in aqueous NaNO3 solution (c = 0.01 mol L-1). The techniques visualized the lower initial corrosion rate in buffered synthetic body fluid (Hank's balanced salt solution; pH 7.6) compared to unbuffered NaNO3 (pH 6.0), but precise localization of Mg corrosion remains challenging under these conditions. To further demonstrate the capability of DGT LA-ICP-MS for spatiotemporal metal flux imaging at the microscale, a coated Mg alloy (c-WE43) with lower reactivity was deployed for ≤120 min. The high spatial resolution (∼10 µm × 80 µm) and low limits of detection (≤0.04 ng cm-2 s-1, t = 60 min) enabled accurate in situ localization and quantification (Urel = 20%, k = 2) of distinct Mg2+ flux increase, showing micro-confined release of Mg2+ from surface coating defects on c-WE43 samples. The presented approach can be extended to other metal species and applied to other materials to better understand corrosion processes and improve material design in technological engineering.


Assuntos
Terapia a Laser , Magnésio , Ligas , Corrosão , Difusão
4.
Elife ; 112022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35049498

RESUMO

Regulation of gene expression requires the combinatorial binding of sequence-specific transcription factors (TFs) at promoters and enhancers. Prior studies showed that alterations in the spacing between TF binding sites can influence promoter and enhancer activity. However, the relative importance of TF spacing alterations resulting from naturally occurring insertions and deletions (InDels) has not been systematically analyzed. To address this question, we first characterized the genome-wide spacing relationships of 73 TFs in human K562 cells as determined by ChIP-seq (chromatin immunoprecipitation sequencing). We found a dominant pattern of a relaxed range of spacing between collaborative factors, including 45 TFs exclusively exhibiting relaxed spacing with their binding partners. Next, we exploited millions of InDels provided by genetically diverse mouse strains and human individuals to investigate the effects of altered spacing on TF binding and local histone acetylation. These analyses suggested that spacing alterations resulting from naturally occurring InDels are generally tolerated in comparison to genetic variants directly affecting TF binding sites. To experimentally validate this prediction, we introduced synthetic spacing alterations between PU.1 and C/EBPß binding sites at six endogenous genomic loci in a macrophage cell line. Remarkably, collaborative binding of PU.1 and C/EBPß at these locations tolerated changes in spacing ranging from 5 bp increase to >30 bp decrease. Collectively, these findings have implications for understanding mechanisms underlying enhancer selection and for the interpretation of non-coding genetic variation.


Assuntos
Regulação da Expressão Gênica , Genômica/métodos , Fatores de Transcrição/genética , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Imunoprecipitação da Cromatina , Elementos Facilitadores Genéticos , Humanos , Células K562 , Masculino , Camundongos , Ligação Proteica , Proteínas Proto-Oncogênicas/genética , Transativadores/genética
5.
Wien Med Wochenschr ; 171(15-16): 356-362, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33765204

RESUMO

Two different strands of hair taken from Beethoven's head after his death were examined for heavy metals using scanning electron microscopy (SEM) and laser ablation-ICP-MS (inductively coupled plasma-mass spectroscopy). The results revealed the presence of small lead particles on the surface of Beethoven's hairs and fluctuating lead levels in hair medulla along the length of the hair due to alternating lead exposure, with an average lead exposure of 100 times the normal value. The time-line attached to the peaks of these fluctuating values correlate with the pneumonia treatment and the paracenteses performed, including the subsequent treatment of the procedure wounds. While the administration of lead-containing drugs and treatments had been proven to resolve the pneumonia, it had simultaneously caused massive liver failure, accelerated by pre-existing cirrhosis. The question as to whether Beethoven's death was a case of malpractice can only be answered from a forensic point of view ex ante, since the state of the medical knowledge of the time has to be taken into account.


Assuntos
Pessoas Famosas , Terapia a Laser , Imperícia , Humanos , Chumbo
6.
Sci Total Environ ; 738: 140311, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32806385

RESUMO

Trace element concentrations in the rhizosphere were quantified to better understand why soil liming often fails to reduce cadmium (Cd) uptake by plants. Maize seedlings were grown on a soil with natural background levels of Cd and zinc (Zn). Soil liming increased soil pH from 4.9 to 6.5 and lowered the soil solution free ion activities by factor 7 (Cd) and 9 (Zn). In contrast, shoot Cd concentrations were unaffected by liming while shoot Zn concentrations were lowered by factor 1.9. Mapping of labile soil trace elements using diffusive gradients in thin films (DGT) in combination with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) revealed an almost complete depletion of Cd in the rhizosphere in all soil treatments, showing that Cd uptake is controlled by diffusion. The flux of Cd from soil to the DGT, with direct contact between the soil and the binding gel, was unaffected by liming whereas it decreased by factor 3 for Zn, closely mimicking the contrasting effects of liming on Cd and Zn bioavailability. This evidence, combined with additional flux data of freshly spiked Cd and Zn isotopes in soil and with modelling, suggests that the diffusive transport of Cd in unsaturated soil is more strongly controlled by the labile adsorbed metal concentration than by its concentration in solution. This is less the case for Zn because of its inherently slower desorption compared to Cd.


Assuntos
Poluentes do Solo/análise , Oligoelementos , Cádmio/análise , Rizosfera , Solo , Zea mays , Zinco/análise
7.
Gerontologist ; 59(Suppl 1): S50-S56, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31100141

RESUMO

There is growing evidence that older adults exposed to natural disasters are at disproportionate risk for adverse health events such as all-cause mortality, injury, hospital admissions, stroke, displacement, cardiopulmonary distress, stress-related mental health problems, and exacerbation of chronic illnesses. Typically, analyses of the health consequences of natural disasters focus only on the populations impacted for the duration and immediate aftermath of the disaster. With few exceptions, the long-term effects of natural disasters on older adult health have not been examined. This article describes the potential consequences of exposure to natural disasters that contribute to cancer and disruption of cancer care treatment systems for older adults. It is argued that exposures to floods and wildfires in particular present an underestimated threat to the onset and/or progression of cancer and cancer care management in older adults. We propose that these impacts should be examined not only from an emergency preparedness perspective during the event but also from a public health focus that prospectively assesses risks for cancer and other health disparities. Recommendations for comprehensive longitudinal risk assessment and emergency preparedness models that address the full impact of natural disasters on the health and well-being of vulnerable, at risk, older adults are offered.


Assuntos
Disparidades nos Níveis de Saúde , Desastres Naturais , Neoplasias , Idoso , Doença Crônica , Humanos , Saúde Pública , Medição de Risco , Sobreviventes/psicologia , Populações Vulneráveis
8.
J Immunol ; 200(5): 1702-1717, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29378911

RESUMO

B-1 cells are a unique subset of B cells that are positively selected for expressing autoreactive BCRs. We isolated RNA from peritoneal (B-1a, B-1b, B-2) and splenic (B-1a, marginal zone, follicular) B cells from C57BL/6 mice and used 5'-RACE to amplify the IgH V region using massively parallel sequencing. By analyzing 379,000 functional transcripts, we demonstrate that B-1a cells use a distinct and restricted repertoire. All B-1 cell subsets, especially peritoneal B-1a cells, had a high proportion of sequences without N additions, suggesting predominantly prenatal development. Their transcripts differed markedly and uniquely contained VH11 and VH12 genes, which were rearranged only with a restricted selection of D and J genes, unlike other V genes. Compared to peritoneal B-1a, the peritoneal B-1b repertoire was larger, had little overlap with B-1a, and most sequences contained N additions. Similarly, the splenic B-1a repertoire differed from peritoneal B-1a sequences, having more unique sequences and more frequent N additions, suggesting influx of B-1a cells into the spleen from nonperitoneal sites. Two CDR3s, previously described as Abs to bromelain-treated RBCs, comprised 43% of peritoneal B-1a sequences. We show that a single-chain variable fragment designed after the most prevalent B-1a sequence bound oxidation-specific epitopes such as the phosphocholine of oxidized phospholipids. In summary, we provide the IgH V region library of six murine B cell subsets, including, to our knowledge for the first time, a comparison between B-1a and B-1b cells, and we highlight qualities of B-1 cell Abs that indicate unique selection processes.


Assuntos
Anticorpos/genética , Anticorpos/imunologia , Subpopulações de Linfócitos B/imunologia , Baço/imunologia , Sequência de Aminoácidos , Animais , Diversidade de Anticorpos/genética , Diversidade de Anticorpos/imunologia , Sequência de Bases , Feminino , Genes de Imunoglobulinas/genética , Genes de Imunoglobulinas/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/imunologia , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Camundongos , Camundongos Endogâmicos C57BL
9.
Acta Biomater ; 51: 526-536, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28111338

RESUMO

This pilot study highlights the substantial potential of using isotopically enriched (non-radioactive) metals to study the fate of biodegradable metal implants. It was possible to show that magnesium (Mg) release can be observed by combining isotopic mass spectrometry and isotopic pattern deconvolution for data reduction, even at low amounts of Mg released a from slowly degrading 26Mg enriched (>99%) Mg metal. Following implantation into rats, structural in vivo changes were monitored by µCT. Results showed that the applied Mg had an average degradation rate of 16±5µmyear-1, which corresponds with the degradation rate of pure Mg. Bone and tissue extraction was performed 4, 24, and 52weeks after implantation. Bone cross sections were analyzed by laser ablation inductively coupled plasma mass spectrometry (ICP-MS) to determine the lateral 26Mg distribution. The 26Mg/24Mg ratios in digested tissue and excretion samples were analyzed by multi collector ICP-MS. Isotope pattern deconvolution in combination with ICP-MS enabled detection of Mg pin material in amounts as low as 200ppm in bone tissues and 20ppm in tissues up to two fold increased Mg levels with a contribution of pin-derived Mg of up to 75% (4weeks) and 30% (24weeks) were found adjacent to the implant. After complete degradation, no visual bone disturbance or residual pin-Mg could be detected in cortical bone. In organs, increased Δ26Mg/24Mg values up to 16‰ were determined compared to control samples. Increased Δ26Mg/24Mg values were detected in serum samples at a constant total Mg level. In contrast to urine, feces did not show a shift in the 26Mg/24Mg ratios. This investigation showed that the organism is capable of handling excess Mg well and that bones fully recover after degradation. STATEMENT OF SIGNIFICANCE: Magnesium alloys as bone implants have faced increasing attention over the past years. In vivo degradation and metabolism studies of these implant materials have shown the promising application in orthopaedic trauma surgery. With advance in Mg research it has become increasingly important to monitor the fate of the implant material in the organism. For the first time, the indispensible potential of isotopically enriched materials is documented by applying 26Mg enriched Mg implants in an animal model. Therefore, the spatial distribution of pin-Mg in bone and the pin-Mg migration and excretion in the organism could be monitored to better understand metal degradation as well as Mg turn over and excretion.


Assuntos
Implantes Absorvíveis , Osso e Ossos/efeitos dos fármacos , Implantes Experimentais , Magnésio/farmacologia , Animais , Osso e Ossos/diagnóstico por imagem , Bovinos , Imageamento Tridimensional , Isótopos , Limite de Detecção , Magnésio/sangue , Magnésio/urina , Ratos Sprague-Dawley , Fatores de Tempo
10.
Anal Chem ; 88(12): 6223-30, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27240571

RESUMO

An optimized method is described for U/Pu separation and subsequent measurement of the amount contents of uranium isotopes by total evaporation (TE) TIMS with a double filament setup combined with filament carburization for age determination of plutonium samples. The use of carburized filaments improved the signal behavior for total evaporation TIMS measurements of uranium. Elevated uranium ion formation by passive heating during rhenium signal optimization at the start of the total evaporation measurement procedure was found to be a result from byproducts of the separation procedure deposited on the filament. This was avoided using carburized filaments. Hence, loss of sample before the actual TE data acquisition was prevented, and automated measurement sequences could be accomplished. Furthermore, separation of residual plutonium in the separated uranium fraction was achieved directly on the filament by use of the carburized filaments. Although the analytical approach was originally tailored to achieve reliable results only for the (238)Pu/(234)U, (239)Pu/(235)U, and (240)Pu/(236)U chronometers, the optimization of the procedure additionally allowed the use of the (242)Pu/(238)U isotope amount ratio as a highly sensitive indicator for residual uranium present in the sample, which is not of radiogenic origin. The sample preparation method described in this article has been successfully applied for the age determination of CRM NBS 947 and other sulfate and oxide plutonium samples.

11.
Diabetes Educ ; 42(4): 452-61, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27324747

RESUMO

PURPOSE: The purpose of this study is to examine the relationship between depressive symptoms and diabetes self-care in African American and Hispanic/Latino patients with type 2 diabetes and whether the association, if any, is mediated by diabetes-related self-efficacy. METHODS: The sample included self-report baseline data of African American and Hispanic/Latino patients with type 2 diabetes who were aged ≥18 years and enrolled in a diabetes self-management intervention study. Depressive symptoms were assessed with the 9-item Patient Health Questionnaire. The Summary of Diabetes Self-care Activities measured engagement in healthy eating, physical activity, blood glucose checking, foot care, and smoking. The Diabetes Empowerment Scale-Short Form assessed diabetes-related psychosocial self-efficacy. Indirect effects were examined with the Baron and Kenny regression technique and Sobel testing. RESULTS: Sample characteristics (n = 250) were as follows: mean age of 53 years, 68% women, 54% African American, and 74% with income <$20 000. Depressive symptoms showed a significant inverse association with the self-care domains of general diet, specific diet, physical activity, and glucose monitoring in the African American group. In Hispanics/Latinos, depression was inversely associated with specific diet. Self-efficacy served a significant mediational role in the relation between depression and foot care among African Americans. CONCLUSIONS: Self-efficacy mediated the relationship between depression and foot care in the African American group but was not found to be a mediator of any self-care areas within the Hispanic/Latino group. In clinical practice, alleviation of depressive symptoms may improve self-care behavior adherence. Diabetes education may consider inclusion of components to build self-efficacy related to diabetes self-care, especially among African American patients.


Assuntos
Negro ou Afro-Americano/psicologia , Depressão/etnologia , Diabetes Mellitus Tipo 2/psicologia , Diabetes Mellitus Tipo 2/terapia , Hispânico ou Latino/psicologia , Autocuidado/psicologia , Autoeficácia , Adulto , Idoso , Automonitorização da Glicemia/psicologia , Estudos Transversais , Dieta para Diabéticos/psicologia , Exercício Físico/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Análise de Regressão , Autorrelato , Fumar/etnologia , Estados Unidos
12.
Environ Pollut ; 216: 215-222, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27263113

RESUMO

Arsenic is a non-threshold carcinogenic metalloid. Thus, human exposure should be minimised, e.g. by chemically stabilizing As in soil. Since iron is a potential As immobiliser, it was investigated whether root iron plaque, formed under aerobic conditions, affects As uptake, metabolism and distribution in Lupinus albus plants. White lupin plants were cultivated in a continuously aerated hydroponic culture containing Fe/EDDHA or FeSO4 and exposed to arsenate (5 or 20 µM). Only FeSO4 induced surficial iron plaque in roots. LA-ICP-MS analysis accomplished on root sections corroborated the association of As to this surficial Fe. Additionally, As(V) was the predominant species in FeSO4-treated roots, suggesting less efficient As uptake in the presence of iron plaque. Fe/EDDHA-exposed roots neither showed such surficial FeAs co-localisation nor As(V) accumulation; in contrast As(III) was the predominant species in root tissue. Furthermore, FeSO4-treated plants showed reduced shoot-to-root As ratios, which were >10-fold lower compared to Fe/EDDHA treatment. Our results highlight the role of an iron plaque formed in roots of white lupin under aerobic conditions on As immobilisation. These findings, to our knowledge, have not been addressed before for this plant and have potential implications on soil remediation (phytostabilisation) and food security (minimising As in crops).


Assuntos
Arsênio/química , Ferro/farmacologia , Lupinus/metabolismo , Poluentes do Solo/metabolismo , Arsênio/análise , Arsênio/metabolismo , Recuperação e Remediação Ambiental/métodos , Hidroponia , Ferro/metabolismo , Lupinus/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Solo , Poluentes do Solo/análise , Poluentes do Solo/química
13.
Arterioscler Thromb Vasc Biol ; 36(4): 682-91, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26868208

RESUMO

OBJECTIVE: Little is known about the role(s) B cells play in obesity-induced metabolic dysfunction. This study used a mouse with B-cell-specific deletion of Id3 (Id3(Bcell KO)) to identify B-cell functions involved in the metabolic consequences of obesity. APPROACH AND RESULTS: Diet-induced obese Id3(Bcell KO) mice demonstrated attenuated inflammation and insulin resistance in visceral adipose tissue (VAT), and improved systemic glucose tolerance. VAT in Id3(Bcell KO) mice had increased B-1b B cells and elevated IgM natural antibodies to oxidation-specific epitopes. B-1b B cells reduced cytokine production in VAT M1 macrophages, and adoptively transferred B-1b B cells trafficked to VAT and produced natural antibodies for the duration of 13-week studies. B-1b B cells null for Id3 demonstrated increased proliferation, established larger populations in Rag1(-/-) VAT, and attenuated diet-induced glucose intolerance and VAT insulin resistance in Rag1(-/-) hosts. However, transfer of B-1b B cells unable to secrete IgM had no effect on glucose tolerance. In an obese human population, results provided the first evidence that B-1 cells are enriched in human VAT and IgM antibodies to oxidation-specific epitopes inversely correlated with inflammation and insulin resistance. CONCLUSIONS: NAb-producing B-1b B cells are increased in Id3(Bcell KO) mice and attenuate adipose tissue inflammation and glucose intolerance in diet-induced obese mice. Additional findings are the first to identify VAT as a reservoir for human B-1 cells and to link anti-inflammatory IgM antibodies with reduced inflammation and improved metabolic phenotype in obese humans.


Assuntos
Subpopulações de Linfócitos B/metabolismo , Intolerância à Glucose/prevenção & controle , Cadeias mu de Imunoglobulina/metabolismo , Inflamação/prevenção & controle , Resistência à Insulina , Gordura Intra-Abdominal/metabolismo , Obesidade/complicações , Transferência Adotiva , Animais , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/transplante , Biomarcadores/sangue , Glicemia/metabolismo , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Genótipo , Intolerância à Glucose/sangue , Intolerância à Glucose/genética , Intolerância à Glucose/imunologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Cadeias mu de Imunoglobulina/genética , Cadeias mu de Imunoglobulina/imunologia , Inflamação/sangue , Inflamação/genética , Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Proteínas Inibidoras de Diferenciação/genética , Proteínas Inibidoras de Diferenciação/metabolismo , Insulina/sangue , Gordura Intra-Abdominal/imunologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/sangue , Obesidade/genética , Obesidade/imunologia , Fenótipo , Fatores de Tempo , Técnicas de Cultura de Tecidos
14.
Anal Bioanal Chem ; 408(2): 431-40, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26168968

RESUMO

Laser ablation-multi-collector-inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) was optimized and investigated with respect to its performance for determining spatially resolved Pu isotopic signatures within radioactive fuel particle clusters. Fuel particles had been emitted from the Chernobyl nuclear power plant (ChNPP) where the 1986 accident occurred and were deposited in the surrounding soil, where weathering processes caused their transformation into radioactive clusters, so-called micro-samples. The size of the investigated micro-samples, which showed surface alpha activities below 40 mBq, ranged from about 200 to 1000 µm. Direct single static point ablations allowed to identify variations of Pu isotopic signatures not only between distinct fuel particle clusters but also within individual clusters. The resolution was limited to 100 to 120 µm as a result of the applied laser ablation spot sizes and the resolving power of the nuclear track radiography methodology that was applied for particle pre-selection. The determined (242)Pu/(239)Pu and (240)Pu/(239)Pu isotope ratios showed a variation from low to high Pu isotope ratios, ranging from 0.007(2) to 0.047(8) for (242)Pu/(239)Pu and from 0.183(13) to 0.577(40) for (240)Pu/(239)Pu. In contrast to other studies, the applied methodology allowed for the first time to display the Pu isotopic distribution in the Chernobyl fallout, which reflects the differences in the spent fuel composition over the reactor core. The measured Pu isotopic signatures are in good agreement with the expected Pu isotopic composition distribution that is typical for a RBMK-1000 reactor, indicating that the analyzed samples are originating from the ill-fated Chernobyl reactor. The average Pu isotope ratios [(240)Pu/(239)Pu = 0.388(86), (242)Pu/(239)Pu = 0.028(11)] that were calculated from all investigated samples (n = 48) correspond well to previously published results of Pu analyses in contaminated samples from the vicinity of the Chernobyl NPP [e.g. (240)Pu/(239)Pu = 0.394(2) and (242)Pu/(239)Pu = 0.027(1); Nunnemann et al. (J Alloys Compd 271-273:45-48, 1998)].

15.
Circ Res ; 117(3): e28-39, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-26082558

RESUMO

RATIONALE: B cells contribute to atherosclerosis through subset-specific mechanisms. Whereas some controversy exists about the role of B-2 cells, B-1a cells are atheroprotective because of secretion of atheroprotective IgM antibodies independent of antigen. B-1b cells, a unique subset of B-1 cells that respond specifically to T-cell-independent antigens, have not been studied within the context of atherosclerosis. OBJECTIVE: To determine whether B-1b cells produce atheroprotective IgM antibodies and function to protect against diet-induced atherosclerosis. METHODS AND RESULTS: We demonstrate that B-1b cells are sufficient to produce IgM antibodies against oxidation-specific epitopes on low-density lipoprotein both in vitro and in vivo. In addition, we demonstrate that B-1b cells provide atheroprotection after adoptive transfer into B- and T-cell deficient (Rag1(-/-)Apoe(-/-)) hosts. We implicate inhibitor of differentiation 3 (Id3) in the regulation of B-1b cells as B-cell-specific Id3 knockout mice (Id3(BKO)Apoe(-/-)) have increased numbers of B-1b cells systemically, increased titers of oxidation-specific epitope-reactive IgM antibodies, and significantly reduced diet-induced atherosclerosis when compared with Id3(WT)Apoe(-/-) controls. Finally, we report that the presence of a homozygous single nucleotide polymorphism in ID3 in humans that attenuates Id3 function is associated with an increased percentage of circulating B-1 cells and anti-malondialdehyde-low-density lipoprotein IgM suggesting clinical relevance. CONCLUSIONS: These results provide novel evidence that B-1b cells produce atheroprotective oxidation-specific epitope-reactive IgM antibodies and protect against atherosclerosis in mice and suggest that similar mechanisms may occur in humans.


Assuntos
Aterosclerose/imunologia , Subpopulações de Linfócitos B/imunologia , Imunoglobulina M/imunologia , Lipoproteínas LDL/imunologia , Malondialdeído/análogos & derivados , Transferência Adotiva , Animais , Especificidade de Anticorpos , Aorta/patologia , Apolipoproteínas E/deficiência , Aterosclerose/sangue , Aterosclerose/genética , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Subpopulações de Linfócitos B/transplante , Células Cultivadas , Colesterol/sangue , Cobre/imunologia , Dieta Ocidental/efeitos adversos , Epitopos/imunologia , Proteínas de Homeodomínio/genética , Humanos , Proteínas Inibidoras de Diferenciação/deficiência , Proteínas Inibidoras de Diferenciação/genética , Proteínas Inibidoras de Diferenciação/fisiologia , Lipoproteínas LDL/química , Contagem de Linfócitos , Masculino , Malondialdeído/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/fisiologia , Oxirredução , Placa Aterosclerótica/patologia , Polimorfismo de Nucleotídeo Único , Receptor 4 Toll-Like/imunologia
16.
J Lipid Res ; 56(2): 440-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25525116

RESUMO

Oxidation-specific epitopes (OSEs) present on apoptotic cells and oxidized low density lipoprotein (OxLDL) represent danger-associated molecular patterns that are recognized by different arcs of innate immunity, including natural IgM antibodies. Here, we investigated whether circulating microparticles (MPs), which are small membrane vesicles released by apoptotic or activated cells, are physiological carriers of OSEs. OSEs on circulating MPs isolated from healthy donors and patients with ST-segment elevation myocardial infarction (STE-MI) were characterized by flow cytometry using a panel of OSE-specific monoclonal antibodies. We found that a subset of MPs carry OSEs on their surface, predominantly malondialdehyde (MDA) epitopes. Consistent with this, a majority of IgM antibodies bound on the surface of circulating MPs were found to have specificity for MDA-modified LDL. Moreover, we show that MPs can stimulate THP-1 (human acute monocytic leukemia cell line) and human primary monocytes to produce interleukin 8, which can be inhibited by a monoclonal IgM with specificity for MDA epitopes. Finally, we show that MDA(+) MPs are elevated at the culprit lesion site of patients with STE-MI. Our results identify a subset of OSE(+) MPs that are bound by OxLDL-specific IgM. These findings demonstrate a novel mechanism by which anti-OxLDL IgM antibodies could mediate protective functions in CVD.


Assuntos
Micropartículas Derivadas de Células/imunologia , Micropartículas Derivadas de Células/metabolismo , Epitopos/imunologia , Imunoglobulina M/imunologia , Síndrome Coronariana Aguda/imunologia , Síndrome Coronariana Aguda/metabolismo , Adulto , Feminino , Humanos , Masculino , Malondialdeído/metabolismo , Oxirredução
17.
PLoS One ; 7(6): e39262, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22723979

RESUMO

The serine protease inhibitor protein C inhibitor (PCI) is expressed in many human tissues and exhibits broad protease reactivity. PCI binds glycosaminoglycans and certain phospholipids, which modulate its inhibitory activity. Enteropeptidase (EP) is a type II transmembrane serine protease mainly found on the brush border membrane of epithelial cells in the duodenum, where it activates trypsinogen to initiate the digestion of food proteins. Some active EP is also present in duodenal fluid and has been made responsible for causing pancreatitis in case of duodeno-pancreatic reflux. Together with its substrate trypsinogen, EP is furthermore present in the epidermis and in some cancer cells. In this report, we show that PCI inhibited EP with an apparent 2nd order rate constant of 4.48 × 10(4) M(-1) s(-1). Low molecular weight (LMWH) and unfractionated heparin (UFH) slightly reduced the inhibitory effect of PCI. The SI (stoichiometry of inhibition) value for the inhibition of EP by PCI was 10.8 in the absence and 17.9 in the presence of UFH (10 U/ml). By inhibiting trypsin, chymotrypsin, and additionally EP, PCI might play a role in the protection of the pancreas from autodigestion. Furthermore the interaction of PCI with EP may influence the regulation of epithelial differentiation.


Assuntos
Enteropeptidase/metabolismo , Inibidor da Proteína C/metabolismo , Inibidores de Serina Proteinase/metabolismo , Animais , Antitrombinas/metabolismo , Antitrombinas/farmacologia , Bovinos , Relação Dose-Resposta a Droga , Enteropeptidase/antagonistas & inibidores , Heparina/farmacologia , Humanos , Camundongos , Ligação Proteica , Inibidor da Proteína C/farmacologia , Inibidores de Serina Proteinase/farmacologia , Serpinas/metabolismo , Serpinas/farmacologia
18.
Transpl Int ; 22(10): 990-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19619168

RESUMO

Self-care is recommended to kidney transplant recipients as a vital component to maintain long-term graft function. However, little is known about the effects of physical activity, fluid intake, and smoking history on graft function. This longitudinal study examined the relationship between self-care practices on graft function among 88 new kidney transplant recipients in Chicago, IL and Albany, NY between 2005 and 2008. Participants were interviewed, completed surveys, and medical charts were abstracted. Physical activity, fluid intake, and smoking history at baseline were compared with changes in estimated glomerular filtration rate (eGFR) (every 6 months up to 1 year) using bivariate and multivariate regression analysis, while controlling for sociodemographic and clinical transplant variables. Multivariate analyses revealed that greater physical activity was significantly (P < 0.05) associated with improvement in GFR at 6 months; while greater physical activity, absence of smoking history, and nonwhite ethnicity were significant (P < 0.05) predictors of improvement in GFR at 12 months. These results suggest that increasing physical activity levels in kidney recipients may be an effective behavioral measure to help ensure graft functioning. Our findings suggest the need for a randomized controlled trial of exercise, fluid intake, and smoking history on GFR beyond 12 months.


Assuntos
Ingestão de Líquidos/fisiologia , Atividade Motora/fisiologia , Sede/fisiologia , Adulto , Idoso , Feminino , Taxa de Filtração Glomerular/fisiologia , Sobrevivência de Enxerto/fisiologia , Humanos , Transplante de Rim/fisiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Autocuidado , Fumar
19.
Prev Chronic Dis ; 6(1): A14, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19080020

RESUMO

INTRODUCTION: Obesity is associated with coronary heart disease, stroke, certain cancers, hypertension, and type 2 diabetes. Concern about obesity among older adults is growing, and research to examine behaviors associated with risk for increased weight in this population is needed. We examined differences by sex in behaviors associated with overweight and obesity among older adults (aged > or =50 years). METHODS: We analyzed data from the 2005 National Health Interview Survey using logistic regression to predict the likelihood of overweight (body mass index [BMI], 25.0-29.9 kg/m2) and obesity (BMI > or =30.0 kg/m2) relative to healthy weight (BMI, 18.5-24.9 kg/m2) among older adults. We used self-reported weights and heights. Correlates were risk behaviors for chronic disease (smoking status, alcohol intake, consumption of fruits and vegetables, leisure-time physical activity, walking for leisure, walking for transportation, and strength training). RESULTS: Among older men, the prevalence of overweight was 46.3%, and the prevalence of obesity was 25.1%. Among older women, the prevalence of overweight was 33.4%, and the prevalence of obesity was 28.8%. In adjusted logistic regression models, sex differences were observed in the significance of most risk factors for overweight and obesity. Men who were occasional, light, or moderate drinkers were 28% more likely to be obese than men who were nondrinkers; women who were heavy drinkers were 55% less likely to be obese than women who were nondrinkers. Compared with men and women who were regularly active during leisure time, inactive men were 39% more likely to be obese, and inactive women were 28% more likely to be obese. CONCLUSION: Several risk behaviors for chronic disease appear to be associated with overweight and obesity among older adults. Modification of these behaviors has the potential to reduce weight.


Assuntos
Comportamentos Relacionados com a Saúde , Sobrepeso , Idoso , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
20.
J Emerg Nurs ; 34(5): 396-402, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18804711

RESUMO

OBJECTIVE: To evaluate the impact of the GENE course on emergency nurses' geriatric best practices in the emergency department (ED). SAMPLE: A convenience sample of 102 emergency nurses who attended the GENE course at the San Diego convention center on October 3, 2004. METHOD: A prospective method of data collection, with data collection before, immediately after, and three months after attending the course, was used to evaluate the short-term impact of the GENE course on emergency nurses' geriatric knowledge and geriatric care best practices. RESULTS: After attending the GENE course, emergency nurses showed increased a) knowledge of geriatric concepts (p < .000, alpha = .01) and b) self-rated ability to provide care in areas such as functional assessment, assessment of depression, delirium, dementia, polypharmacy, and appropriate referrals to services. ED nurses reported significantly greater utilization of particular geriatric assessment tools and greater incorporation of knowledge and skills related to the assessment of pain, polypharmacy, elder abuse and neglect, and atypical presentation of illness as part of their practice. Finally, a significant increase in the number of emergency departments that incorporated geriatric protocols of care was reported (p = .003, alpha = .05).


Assuntos
Benchmarking/organização & administração , Educação Continuada em Enfermagem/organização & administração , Enfermagem em Emergência/educação , Enfermagem Geriátrica/educação , Recursos Humanos de Enfermagem Hospitalar/educação , Adulto , Idoso , Atitude do Pessoal de Saúde , California , Competência Clínica , Currículo , Enfermagem em Emergência/normas , Feminino , Avaliação Geriátrica , Enfermagem Geriátrica/normas , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação em Enfermagem , Pesquisa em Educação em Enfermagem , Recursos Humanos de Enfermagem Hospitalar/psicologia , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Autoeficácia , Inquéritos e Questionários
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