RESUMO
The new TPSâ 44A beamline at the Taiwan Photon Source, located at the National Synchrotron Radiation Research Center, is presented. This beamline is equipped with a new quick-scanning monochromator (Q-Mono), which can provide both conventional step-by-step scans (s-scans) and on-the-fly scans (q-scans) for X-ray absorption fine-structure (XAFS) spectroscopy experiments, including X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine-structure (EXAFS) spectral measurements. Ti and Te K-edge XAFS spectra were used to demonstrate the capability of collecting spectra at the limits of the working energy range. The Ni and Cu K-edge XAFS spectra for a Cu-doped Pt/Ni nanocomposite were acquired to test the performance of the newly commissioned beamline. Pt L3- and Ru K-edge quick-scanning XAFS (QXAFS) spectra for standard Pt and Ru foils, respectively, revealed the stability of the q-scan technique. The results also demonstrated the beamline's ability to collect XAFS spectra on a sub-second timescale. Furthermore, a Zn(s)|Zn2+(aq)|Cu(s) system was tested to indicate that the states of the Zn electrode could be observed in real time for charging and discharging conditions using an in situ/operando setup combined with QXAFS measurements.
RESUMO
Decabromodiphenyl ether (BDE-209), a congener of polybrominated diphenyl ethers, is a commonly used brominated flame retardant and a known endocrine disrupting chemical (EDC). Knowledge about the effects of prenatal BDE-209 exposure on male reproduction and whether transgenerational effects occur in subsequent generations are scant. Therefore, in this study, we tested the hypothesis that prenatal exposure to BDE-209 disrupted sperm function in the F1, F2, and F3 generations of male rats. Pregnant Sprague-Dawley rats were treated by gavage from gestation day 0 to birth with 5 mg BDE-209/kg/day. This treatment was based on the lowest-observed-adverse-effect level for DNA damage to sperm in male offspring. On postnatal day 84 for all generations, epididymal sperm counts, motility, morphology, reactive oxygen species generation, sperm chromatin DNA structure integrity, testicular DNA content in spermatogenesis, and serum testosterone levels were assessed. DNA methyltransferase (Dnmts) mRNA expression and methyl-CpG binding domain sequencing were also examined to analyze DNA methylation status in the F3 generation. In the F1 generation, prenatal exposure to BDE-209 disrupted body weight, decreased anogenital distance (AGD), sperm count, and motility; and increased bent tail rates of sperm. In the F2 generation, exposure to BDE-209 decreased AGD, sperm count, normal morphology rates, Dnmt1 expression, and increased Dnmt3a expression. In the F3 generation, BDE-209 exposure decreased AGD and normal sperm morphology, disrupted testicular elongated spermatid and round spermatid rates, reduced serum testosterone levels, and inhibited the mRNA expression of Dnmt1 and Dnmt3b. Compared with the control group, there existed 215 differentially hyper-methylated and 83 hypo-methylated genes in the BDE-209 group. BDE-209 is an EDC to disrupt the male reproduction from F1 to F3. BDE-209-induced changes in sperm function and hyper- or hypo-DNA methylation in the F3 generation might therefore explain the possible mechanism underlying BDE-209-mediated epigenetic transgenerational effects on the male reproductive system.
Assuntos
Disruptores Endócrinos , Efeitos Tardios da Exposição Pré-Natal , Animais , DNA , Disruptores Endócrinos/farmacologia , Feminino , Genitália Masculina , Éteres Difenil Halogenados/toxicidade , Humanos , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , RNA Mensageiro , Ratos , Ratos Sprague-Dawley , Reprodução , Espermatogênese , TestosteronaRESUMO
We evaluated unpredictable critical conditions of patients treated in the Emergency Department (ED) observation unit, who were transferred into the emergency resuscitation room from January 1 through June 30, 2001. A total of 175 patients were observed for the following critical conditions: dyspnea (51 patients; 29.14%), hypotension (28; 16.00%), chest pain (18; 10.29%), dysrhythmia (15; 8.57%), hematemesis (15; 8.57%), altered mental status (12; 6.85%), shock (10; 5.71%), coma (8; 4.57%), apnea (5; 2.86%), hematochezia (3; 1.72%), seizure (3; 1.72%), and others (7; 4.00%). The 27 patients who had cardiopulmonary resuscitation (CPR), endotracheal tube intubation, or cardioversion/defibrillation in the ED suffered an in-ED mortality of 25.9% (7) and an in-hospital mortality of 59.2% (16). The remaining 148 patients who received appropriate treatment, except for the above, had a lower in-hospital mortality (20.28%, 30 patients) (p < 0.05). We should limit the number of patients in the observation unit to avoid overloading, and classify patients according to their clinical conditions. We should determine whether or not they have definite diagnoses or are waiting for hospital admission while receiving simple treatments. The observation unit must be provided with well-trained staff and suitable physical facilities with support services, and rapid specialty consultations must be available.