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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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Background: Routine pathological examination can miss micro-metastatic tumor foci in the lymph nodes (LN) of patients with prostate cancer (PCa) that undergo radical prostatectomy and pelvic lymph node dissection (PLND). The aim of the present prospective study was to evaluate the impact of micrometastases assessed by serial section (SS), immunohistochemistry (IHC), and Real-time Polymerase Chain Reaction (RT-PCR) in patients undergoing radical prostatectomy with extended PLND. Materials and methods: 32 consecutive patients who underwent radical prostatectomy with extended PLND (obturator, internal/external and distal 2cm common iliac lymph-nodes (LN)) for intermediate (clinical T1c-T2 and PSA:10-20 ng/mL and clinical Gleason Score = 7) or high (clinical stage T3 or PSA>20 or clinical Gleason Score = 8-10) PCa were enrolled. The nodes were processed by the one uropathologist, both according to the routine pathological examination (analysis of the central section for 4 mm nodes or every 2 mm for LN>4 mm), which served as comparative method, both according to SS, IHC with antibodies against PSA and broad-spectrum Cytokeratins (BSCK), and quantitative RT-PCR targeting PSA, PSMA (PS Membrane Antigen), and Glucuronidase-S-Beta (GUSB) mRNA, that are over-expressed in prostatic cancer cells. Results: A total of 628 LN were analyzed, with a mean number of LN removed of 19.6 (SD = 7.2). Applying the routine pathological examination, 10 (31.2%) patients and 23 (3.9%) LN resulted positive for nodal involvement, with mean positive LN of 2.2 (SD = 1.4). After applying the SS and the molecular method of analysis (IHC and RT-PCR), micrometastases were found in 7 LN (SS showed micrometastases in 3 of them, IHC in 6 of them and RT-PCR in 7 of them); a total of 3 (9.3%) node-negative patients showed micrometastases at routine pathological examination (in 2 patients with RT-PCR and in 1 with IHC). Conclusions: The significance of micrometastases in PCa and the potential therapeutic role of PLND is not yet clarified, but the molecular analysis of the LN can detect a significant percentage of patients who harbor micro-metastatic PCa missed at routine pathological examination, and can enhance the accuracy of lymphadenectomy as a staging method.  相似文献   
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