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Kα,ß X-ray lines from photon excitation were measured in selected elements from Mg to Cu using a high-resolution double-crystal X-ray spectrometer with a proportional counter, and the Kß/Kα intensity ratio for each element was obtained, after correcting for self-absorption, detection efficiency, and crystal reflectance. This intensity ratio increases rapidly from Mg to Ca but, in the 3d elements region, the increase becomes slower. This is related to the intensity of the Kß line involving valence electrons. The slow increase of this ratio in the 3d elements region is thought to be due to the correlation between 3d and 4s electrons. Moreover, the chemical shifts, FWHM, asymmetry indices, and Kß/Kα intensity ratios of the Cr compounds, due to different valences, were also investigated using the same double-crystal X-ray spectrometer. The chemical effects were clearly observed, and the Kß/Kα intensity ratio was found to be compound-dependent for Cr.
Assuntos
Elétrons , Raios XRESUMO
BACKGROUND & AIMS: Mitochondrial dysfunction disrupts the synthesis and secretion of digestive enzymes in pancreatic acinar cells and plays a primary role in the etiology of exocrine pancreas disorders. However, the transcriptional mechanisms that regulate mitochondrial function to support acinar cell physiology are poorly understood. Here, we aim to elucidate the function of estrogen-related receptor γ (ERRγ) in pancreatic acinar cell mitochondrial homeostasis and energy production. METHODS: Two models of ERRγ inhibition, GSK5182-treated wild-type mice and ERRγ conditional knock-out (cKO) mice, were established to investigate ERRγ function in the exocrine pancreas. To identify the functional role of ERRγ in pancreatic acinar cells, we performed histologic and transcriptome analysis with the pancreas isolated from ERRγ cKO mice. To determine the relevance of these findings for human disease, we analyzed transcriptome data from multiple independent human cohorts and conducted genetic association studies for ESRRG variants in 2 distinct human pancreatitis cohorts. RESULTS: Blocking ERRγ function in mice by genetic deletion or inverse agonist treatment results in striking pancreatitis-like phenotypes accompanied by inflammation, fibrosis, and cell death. Mechanistically, loss of ERRγ in primary acini abrogates messenger RNA expression and protein levels of mitochondrial oxidative phosphorylation complex genes, resulting in defective acinar cell energetics. Mitochondrial dysfunction due to ERRγ deletion further triggers autophagy dysfunction, endoplasmic reticulum stress, and production of reactive oxygen species, ultimately leading to cell death. Interestingly, ERRγ-deficient acinar cells that escape cell death acquire ductal cell characteristics, indicating a role for ERRγ in acinar-to-ductal metaplasia. Consistent with our findings in ERRγ cKO mice, ERRγ expression was significantly reduced in patients with chronic pancreatitis compared with normal subjects. Furthermore, candidate locus region genetic association studies revealed multiple single nucleotide variants for ERRγ that are associated with chronic pancreatitis. CONCLUSIONS: Collectively, our findings highlight an essential role for ERRγ in maintaining the transcriptional program that supports acinar cell mitochondrial function and organellar homeostasis and provide a novel molecular link between ERRγ and exocrine pancreas disorders.
Assuntos
Pâncreas Exócrino , Pancreatite Crônica , Células Acinares/patologia , Animais , Estrogênios/metabolismo , Humanos , Camundongos , Camundongos Knockout , Pâncreas/patologia , Pâncreas Exócrino/metabolismo , Pancreatite Crônica/patologiaRESUMO
In order to determine ammonium ion in water samples, we propose a method based on the Berthelot reaction of ammonia with 1-naphthol and dichloroisocyanurate to form an indophenol blue derivative and collection of the blue compound as an ion pair using Zephiramine on a pure polytetrafluoroethylene (PTFE)-type membrane filter. The ion pair on the filter was eluted with 5.0 mL of acetonitrile, and the absorbance of the eluate was measured at 725 nm. The detection limit of the method was 2.5 microg L(-1) of ammonium ion. We showed that the interference of foreign ions was removed by the addition of EDTA. We also demonstrated the success of the method in determining ammonia in river water and seawater.
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Amônia/análise , Filtração/instrumentação , Indóis/química , Membranas Artificiais , Naftóis/química , Espectrofotometria/métodos , Triazinas/química , Amônia/química , Amônia/isolamento & purificação , Compostos de Benzalcônio/química , Indicadores e Reagentes/química , Indóis/isolamento & purificação , Rios/química , Água do Mar/química , Solventes/química , Fatores de TempoRESUMO
X-ray fluorescence analysis using Cr K(alpha) spectra was applied to the determination of the mixing ratio of Cr(6+) to (Cr(6+) + Cr(3+)) in several mixtures of K(2)CrO(4) and Cr(2)O(3). Because the powder of K(2)CrO(4) contained large particles that were more than 50 microm in diameter, it was ground between a pestle and a mortar for about 8 h. The coarse particles still remaining were removed by using a sieve with 325-mesh (44 microm) in order to reduce the difference in absorption effects between emissions from Cr(6+) and those from Cr(3+). The mixing ratio, K(2)CrO(4)/(K(2)CrO(4) + Cr(2)O(3)), of the five mixtures investigated is 0.50, 0.40, 0.20, 0.10, and 0.05 in weight, respectively. Each spectrum obtained was analyzed by decomposing it into two reference spectra, those of the two pure materials, K(2)CrO(4) and Cr(2)O(3), with a constant background. The results for the mixtures containing K(2)CrO(4) of more than 20 wt% are that the relative deviation from the true value is less than approximately 5%. On the other hand, when the content of K(2)CrO(4) decreases to less than 10 wt%, the relative deviation gets so large as 20 - 25%. The error coming from a peak separation of spectrum involved in our results were estimated by applying our method to five sets of data for each mixture computationally generated, taking into account the uncertainty in total counts of real measurements.
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LDL-apheresis is now commonly used as the only practical treatment for homozygous familial hypercholestreolemia (homozygous FH). However, even when applying apheresis therapy, the use of a drug or drugs is recommended to suppress the rapid rebound of cholesterol, which usually takes place after each apheresis procedure, and keep the LDL-cholesterol level within or near the optimal range for as long as possible. In this study, the usefulness of ezetimibe, a novel cholesterol-lowering drug, in enhancing the efficacy of apheresis therapy was evaluated in six Japanese patients with homozygous FH undergoing LDL-apheresis in combination with atorvastatin or simvastatin. With the exception of one patient, significant decreases in LDL-cholesterol at 2 weeks after each apheresis procedure were obtained during the period from 4 to 12 weeks of treatment, with an average reduction rate of 9.0% and a range of 4.3-12.6%. This corresponds to a suppression of rebound by approximately 36 mg/dl, from 391 to 355 mg/dl on average, in LDL-cholesterol values. Although the effect is not very strong, ezetimibe nevertheless appears to be a useful drug in combination with statins for those with homozygous FH undergoing LDL-apheresis.
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Anticolesterolemiantes/uso terapêutico , Azetidinas/uso terapêutico , Remoção de Componentes Sanguíneos/métodos , LDL-Colesterol/sangue , Colesterol/sangue , Hiperlipoproteinemia Tipo II/terapia , Triglicerídeos/sangue , Adulto , Idoso , Biomarcadores/sangue , Ezetimiba , Feminino , Seguimentos , Homozigoto , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/genética , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
Structural change of G-quartet formed by telomere G-rich DNA oligomers are investigated by NMR and CD spectroscopy. G-quartet structure changes depending on the length of 5'-terminal sequence.