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Widened pulse pressure is a classic sign of significant left-to-right shunting patent ductus arteriosus (PDA), but little evidence supports this statement in the early life of premature infants with respiratory distress syndrome (RDS) needing nonsteroidal anti-inflammatory drugs (NSAIDs), the pharmacological treatment for PDA. Pulse pressure and urinary endothelin-1 (ET-1) and arginine vasopressin (AVP) vasoactive factors involved in the transitional circulation were measured before and after the NSAIDs treatment of 46 RDS premature infants receiving either ibuprofen (n = 22) or indomethacin (n = 24), with 28 responders and 18 nonresponders to the first NSAIDs course. We found that following pharmacological PDA closure, systolic and diastolic blood pressure significantly increased, maintaining a stable pulse pressure. However, when pharmacological closure failed, the trend (nonsignificant) was for a more consistent increase in systolic than in diastolic blood pressure, which determined a statistically significant widening pulse pressure. In addition, urinary ET-1 excretion rates decreased significantly after PDA closure, whereas persistent more aggressive pharmacological therapy failed. Urinary AVP excretion rates decreased insignificantly after therapy, uninfluenced by the efficacy of the drugs. We concluded that widened pulse pressure is a clinical sign of failed PDA pharmacological closure in RDS premature infants. ET-1 levels remain elevated when NSAIDs fail to interrupt left-to-right PDA shunting that complicates recovery from RDS.  相似文献   
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A 53-year-old woman suffering for 20 years from chronic genitourinary pain was seen in our urogynecological unit. Quality of life assessment by King's Health Questionnaire showed a highly negative impact on quality of life. Clinical examination revealed a painful and swollen distal urethra, and a small fistula was seen located 12 mm proximal to the meatus externus. Perineal ultrasound and magnetic resonance imaging showed multiple cystic formations bilaterally located in the suburethral and paraurethral regions. A diverticulectomy was performed using the vaginal approach. Twelve months after surgery the woman is completely satisfied and only complaining about slight alguria.  相似文献   
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Assessing maximum voluntary bite force is important to characterize the functional state of the masticatory system. Due to several factors affecting the estimation of the maximum bite force, a unique solution combining desirable features such as reliability, accuracy, precision, usability, and comfort is not available. The aim of the present study was to develop a low-cost bite force measurement device allowing for subject-specific customization, comfortable bite force expression, and reliable force estimation over time. The device was realized using an inexpensive load cell, two 3D printed ergonomic forks hosting reusable subject-specific silicone molds, a read-out system based on a low-cost microcontroller, and a wireless link to a personal computer. A simple model was used to estimate bite force taking into account individual morphology and device placement in the mouth. Measurement reliability, accuracy, and precision were assessed on a calibration dataset. A validation procedure on healthy participants was performed to assess the repeatability of the measurements over multiple repetitions and sessions. A 2% precision and 2% accuracy were achieved on measurements of forces in the physiological range of adult bite forces. Multiple recordings on healthy participants demonstrated good repeatability (coefficient of variation 11%) with no significant effect of repetition and session. The novel device provides an affordable and reliable solution for assessing maximum bite force that can be easily used to perform clinical evaluations in single sessions or in longitudinal studies.  相似文献   
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Introduction

African Americans' (AAs) late-onset Alzheimer's disease (LOAD) genetic risk profile is incompletely understood. Including clinical covariates in genetic analyses using informed conditioning might improve study power.

Methods

We conducted a genome-wide association study (GWAS) in AAs employing informed conditioning in 1825 LOAD cases and 3784 cognitively normal controls. We derived a posterior liability conditioned on age, sex, diabetes status, current smoking status, educational attainment, and affection status, with parameters informed by external prevalence information. We assessed association between the posterior liability and a genome-wide set of single-nucleotide polymorphisms (SNPs), controlling for APOE and ABCA7, identified previously in a LOAD GWAS of AAs.

Results

Two SNPs at novel loci, rs112404845 (P = 3.8 × 10?8), upstream of COBL, and rs16961023 (P = 4.6 × 10?8), downstream of SLC10A2, obtained genome-wide significant evidence of association with the posterior liability.

Discussion

An informed conditioning approach can detect LOAD genetic associations in AAs not identified by traditional GWAS.  相似文献   
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The miniaturized metalloenzyme Fe(iii)-mimochrome VI*a (Fe(iii)-MC6*a) acts as an excellent biocatalyst in the H2O2-mediated oxidative dehalogenation of the well-known pesticide and biocide 2,4,6-trichlorophenol (TCP). The artificial enzyme can oxidize TCP with a catalytic efficiency (kcat/KTCPm = 150 000 mM−1 s−1) up to 1500-fold higher than the most active natural metalloenzyme horseradish peroxidase (HRP). UV-visible and EPR spectroscopies were used to provide indications of the catalytic mechanism. One equivalent of H2O2 fully converts Fe(iii)-MC6*a into the oxoferryl-porphyrin radical cation intermediate [(Fe(iv) Created by potrace 1.16, written by Peter Selinger 2001-2019 O)por˙+], similarly to peroxidase compound I (Cpd I). Addition of TCP to Cpd I rapidly leads to the formation of the corresponding quinone, while Cpd I decays back to the ferric resting state in the absence of substrate. EPR data suggest a catalytic mechanism involving two consecutive one-electron reactions. All results highlight the value of the miniaturization strategy for the development of chemically stable, highly efficient artificial metalloenzymes as powerful catalysts for the oxidative degradation of toxic pollutants.

The artificial metalloenzyme FeMC6*a is able to perform the H2O2-mediated dechlorination of 2,4,6-trichlorophenol with unrivalled catalytic efficiency, highlighting its potential application for the removal of toxic pollutants.  相似文献   
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