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Role of multi-parametric MRI of the prostate for screening and staging: Experience with over 1500 cases
No full textAbstractObjectiveContemporary prostate cancer (PCa) screening modalities such as prostate specific antigen (PSA) and digital rectal examination (DRE) are limited in their ability to predict the detection of clinically significant disease. Multi-parametric magnetic resonance imaging (mpMRI) of the prostate has been explored as a staging modality for PCa. Less is known regarding its utility as a primary screening modality. We examined our experience with mpMRI as both a screening and staging instrument.MethodsmpMRI studies performed between 2012 and 2014 in patients without PCa were cross-referenced with transrectal ultrasonography (TRUS) biopsy findings. Statistical analyses were performed to determine association of mpMRI findings with overall cancer diagnoses and clinically significant (Gleason score ≥7) disease. Subgroup analyses were then performed on patients with a history of prior negative biopsy and those without a history of TRUS biopsy. mpMRI studies were also cross-referenced with RP specimens. Statistical analyses determined predictive ability of extracapsular extension (ECE), seminal vesicle involvement (SVI), and pathologic evidence of clinically significant disease (Gleason score ≥7).ResultsFour hundred biopsy naïve or prior negative biopsy patients had positive mpMRI studies. Overall sensitivity, specificity, positive and negative predictive values were 94%, 37%, 58%, and 87%, respectively and 95%, 31%, 42%, and 93%, respectively for overall cancer detection and Gleason score ≥7 disease. In patients with no prior biopsy history, mpMRI sensitivity, specificity, positive and negative predictive values were 94%, 36%, 65%, and 82%, for all cancers, and 95%, 30%, 50%, and 89% for Gleason score≥7 lesions, respectively. In those with prior negative biopsy sensitivity, specificity, positive and negative predictive values were 94%, 37%, 52%, and 90% for all cancers, and 96%, 32%, 36%, and 96% for Gleason score ≥7 lesions, respectively. Seventy-four patients underwent radical prostatectomy (RP) after mpMRI. Lesion size on mpMRI correlated with the presence of Gleason score ≥7 cancers (p = 0.005). mpMRI sensitivity, specificity, positive and negative predictive values were 84%, 39%, 81%, and 44% respectively, for Gleason ≥7 cancer. For ECE and SVI, sensitivity and specificity were 58% and 98% and 44% and 97%, respectively.ConclusionmpMRI is an accurate predictor of TRUS biopsy and RP outcomes. mpMRI has significant potential to change PCa management, particularly in the screening population, in whom a significant proportion may avoid TRUS biopsy. Further studies are necessary to determine how mpMRI should be incorporated into the current PCa screening and staging paradigms
Vertical breast measurement in East Asian women: A guide for mastopexy and reduction to form nonptotic breasts in unilateral prosthetic breast reconstruction
No full textSummaryBackgroundFollowing unilateral breast cancer surgery, mastopexy and reduction of the unaffected breast are often performed to obtain symmetrical breasts. The use of implants in breast reconstruction results in a nonptotic breast. To achieve symmetry following the procedure, the unaffected side should be nonptotic too. However, no study has yet reported any indices for the design of mastopexy and reduction in this direction. We present a new method of preoperative design that uses vertical breast measurements to form nonptotic breasts according to individual breast shapes.MethodsWe performed vertical breast measurements of the unaffected breasts of 193 patients scheduled to undergo surgery for unilateral breast cancer. The vertical base dimension (VBD) and vertical surface dimension (VSD) of the ptotic and nonptotic breasts and the height of the nipple in the nonptotic breast were measured in centimeters.ResultsThe borderline between ptotic and nonptotic breasts was expressed using the formula VSD = 1.13 × VBD + 1.86. The height of the nipple in nonptotic breasts was 0.8 times the distance between the sternal notch and lowest point of the inframammary fold on the midline. From these findings, we formulated a new method for forming a nonptotic breast from a ptotic breast using an inverted T design.ConclusionThese results can be used for the design of mastopexy and reduction when forming a nonptotic breast on the unaffected side. These procedures can be performed without significantly lifting the nipple–areolar complex if required during unilateral prosthetic breast reconstruction
Moving beyond the monosyllable in models of skilled reading: Mega-study of disyllabic nonword reading
No full textAbstractMost English words are polysyllabic, yet research on reading aloud typically focuses on monosyllables. Forty-one skilled adult readers read aloud 915 disyllabic nonwords that shared important characteristics with English words. Stress, pronunciation, and naming latencies were analyzed and compared to data from three computational accounts of disyllabic reading, including a rule-based algorithm (Rastle & Coltheart, 2000) and connectionist approaches (the CDP++ model of Perry, Ziegler, & Zorzi, 2010, and the print-to-stress network of Ševa, Monaghan, & Arciuli, 2009). Item-based regression analyses revealed orthographic and phonological influences on modal human stress assignment, pronunciation variability, and naming latencies, while human and model data comparisons revealed important strengths and weaknesses of the opposing accounts. Our dataset provides the first normative nonword corpus for British English and the largest database of its kind for any language; hence, it will be critical for assessing generalization performance in future developments of computational models of reading
Monte Carlo simulations of the gamma-ray exposure rates of common rocks
No full textAbstractMonte Carlo simulations have been performed to model the gamma ray emission and attenuation properties of common rocks. In geologic materials, 40K, 238U, and 232Th are responsible for most gamma ray production. If the concentration of these radioelements and attenuation factors such as degree of water saturation are known, an estimate of the gamma-ray exposure rate can be made. The results show that there are no significant differences in gamma-ray screening between major rock types. If the total number of radionuclide atoms are held constant then the major controlling factor is density of the rock. Finally, the thickness of regolith or soil overlying rock can be estimated by modeling the exposure rate if the radionuclide contents of both materials are known
An approach to prospective consequential life cycle assessment and net energy analysis of distributed electricity generation
No full textAbstractIncreasing distributed renewable electricity generation is one of a number of technology pathways available to policy makers to meet environmental and other sustainability goals. Determining the efficacy of such a pathway for a national electricity system implies evaluating whole system change in future scenarios. Life cycle assessment (LCA) and net energy analysis (NEA) are two methodologies suitable for prospective and consequential analysis of energy performance and associated impacts. This paper discusses the benefits and limitations of prospective and consequential LCA and NEA analysis of distributed generation. It concludes that a combined LCA and NEA approach is a valuable tool for decision makers if a number of recommendations are addressed. Static and dynamic temporal allocation are both needed for a fair comparison of distributed renewables with thermal power stations to account for their different impact profiles over time. The trade-offs between comprehensiveness and uncertainty in consequential analysis should be acknowledged, with system boundary expansion and system simulation models limited to those clearly justified by the research goal. The results of this approach are explorative, rather than for accounting purposes; this interpretive remit, and the assumptions in scenarios and system models on which results are contingent, must be clear to end users
Effect of novel dietary supplement on metabolism in vitro and in vivo
No full textAbstractObesity is an increasingly prevalent and preventable morbidity with multiple behavioral, surgical and pharmacological interventions currently available. Commercial dietary supplements are often advertised to stimulate metabolism and cause rapid weight and/or fat loss, although few well-controlled studies have demonstrated such effects. We describe a commercially available dietary supplement (purportedly containing caffeine, catechins, and other metabolic stimulators) on resting metabolic rate in humans, and on metabolism, mitochondrial content, and related gene expression in vitro. Human males ingested either a placebo or commercially available supplement (RF) in a randomized double-blind placebo-controlled cross-over fashion. Metabolic rate, respiratory exchange ratio, and blood pressure were measured hourly for 3 h post-ingestion. To investigate molecular effects, human rhabdomyosarcoma cells (RD) and mouse myocytes (C2C12) were treated with various doses of RF for various durations. RF enhanced energy expenditure and systolic blood pressure in human males without altering substrate utilization. In myocytes, RF enhanced metabolism, metabolic gene expression, and mitochondrial content suggesting RF may target common energetic pathways which control mitochondrial biogenesis. RF appears to increase metabolism immediately following ingestion, although it is unclear if RF provides benefits beyond those provided by caffeine alone. Additional research is needed to examine safety and efficacy for human weight loss
Equilibrium, kinetic and diffusion mechanism of Cr(VI) adsorption onto activated carbon derived from wood apple shell
No full textAbstractIn the present investigation, adsorbent activated charcoal was prepared from wood apple shell by chemical activation and used for Cr(VI) removal from aqueous solutions. Powdered wood apple shell was activated by acid H2SO4 and heat treatment in muffle furnace at 600°C for 2h. The specific surface area of prepared activated carbon was found to be 1898m2g−1. Batch adsorption studies reveal that the prepared activated charcoal has a significant capacity for adsorption of Cr(VI) from aqueous solutions. The equilibrium adsorption isotherms investigated in this study include Langmuir and Freundlich at 300K. The Cr(VI) adsorption was found to be maximum (>95.0%) at pH 1.8. Very small amount of adsorbent activated carbon (1.25gL−1) could remove >95.0% Cr(VI) from aqueous solution of initial concentration 75mgL−1. The Langmuir monolayer adsorption capacity of Cr(VI) adsorption on activated carbon was found to be 151.51mgg−1. The dimensionless separation factor (RL) signifies a favorable adsorption of Cr(VI) on activated charcoal. Adsorption kinetic studies reveal that the adsorption of Cr(VI) onto activated carbon was pseudo-second order chemisorptions and follows film-diffusion as well as intra-particle pore-diffusion mechanism
Chemotherapy versus endocrine therapy as first-line treatment in patients with luminal-like HER2-negative metastatic breast cancer: A propensity score analysis
No full textAbstractBackgroundAccording to current guidelines, endocrine therapy (ET) is recommended as first-line treatment of luminal-like metastatic breast cancer (MBC), whereas chemotherapy (CT) should be considered in presence of life-threatening disease. In daily practice, CT is often used outside of this clinical circumstance. Factors influencing first-line choice and the relative impact on outcome are unknown.MethodsA consecutive series of luminal-like HER2-negative MBC patients treated from 2004 to 2014 was analyzed to test the association of disease- and patient-related factors with the choice of first-line treatment (ET vs. CT). A propensity score method was used to estimate impact of first-line strategy on outcome.ResultsOf 604 consecutive luminal-like MBC patients identified, 158 cases were excluded due to unknown or positive HER2-status. Among 446 HER2-negative cases, 171 (38%) received first-line CT. On multivariate analysis, the only factors significantly associated with lower CT use were old age (OR 0.25, 95%C.I. 0.13–0.49) or presence of bone metastases only (OR 0.26, 95%C.I. 0.13–0.53). In propensity score matched population, no differences were observed between CT and ET as first-line treatment either in terms of overall survival (37.5 months and 33.4 months respectively, log-rank test, P = 0.62) or progression-free survival (13.3 months and 9.9 months respectively, log-rank test, P = 0.92).ConclusionsHigh percentage of patients with luminal-like MBC received CT as first-line therapy in real-life. The choice was mainly driven by age and site of metastases. With the limitations of a non-randomized comparison, no differences on patients' outcome were observed depending on the first-line strategy
Persistent Mullerian Duct Syndrome presenting as irreducible inguinal hernia – A surprise surgical finding!
No full textAbstractPersistent Mullerian Duct Syndrome (PMDS) is diagnosed as a discrepancy between masculine external genitalia and female internal genitalia during surgery for cryptorchidism or inguinal hernia. Approximately 200 cases have been reported in the literature so far, most of whom are adults. We discuss the management in an infant presenting with irreducible inguinal hernia with contralateral undescended testis