106 research outputs found

    Histotripsy Effects on the Bladder Trigone: Functional and Histologic Consequences in the Canine Model

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    Background: Histotripsy is an extracorporeal therapeutic ultrasound (US) technology, where high-amplitude acoustic energy is applied to targeted tissue. Previous research has demonstrated the feasibility, safety, and effectiveness of histotripsy tissue homogenization and debulking of the prostate in the canine model. Before translating this technology for human use, it is prudent to examine the susceptibility of critical periprostatic structures to cavitation injury in the event of histotripsy mistargeting. In this study, we sought to characterize the tissue effects and biologic response of directly treating the bladder trigone with histotripsy. Materials and Methods: In eight anesthetized canines, 750,000 histotripsy pulses were applied uniformly across a 2?1.5-cm area encompassing the bladder trigone and ureteral orifices. Prostate and bladder trigone were harvested immediately after treatment (2 subjects) or at 14 days (6 subjects). Flexible cystourethroscopy, US imaging, and creatinine levels were obtained at intervals until harvest, 14 days after treatment. In one control subject, harvested at 2 days, the same treatment algorithm was applied to the prostate. Results: Transrectal US imaging revealed a cavitation bubble cloud on the surface of the bladder trigone and progressive development of tissue edema during treatment. Flexible cystourethroscopy immediately after treatment confirmed edema and erythema of the trigone. In the six subjects survived 2 weeks after treatment, one incidence of transient, self-limited ureteral obstruction was noted based on hydronephrosis and creatinine levels. At harvest, ureteral orifices were confirmed patent by passage of a guide wire. Histologic evaluation revealed hemorrhage acutely with mild localized fibrosis at 14 days. Conclusions: In this study, designed along the lines of a worst-case, destructive testing scenario, direct targeting of the bladder trigone with supratherapeutic histotripsy failed to induce significant tissue damage or clinical complication. These results are reassuring and will guide treatment strategy in upcoming human clinical trials of histotripsy treatment for benign prostatic hyperplasia.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140374/1/end.2013.0234.pd

    A Multilaboratory Comparison of Calibration Accuracy and the Performance of External References in Analytical Ultracentrifugation

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    Analytical ultracentrifugation (AUC) is a first principles based method to determine absolute sedimentation coefficients and buoyant molar masses of macromolecules and their complexes, reporting on their size and shape in free solution. The purpose of this multi-laboratory study was to establish the precision and accuracy of basic data dimensions in AUC and validate previously proposed calibration techniques. Three kits of AUC cell assemblies containing radial and temperature calibration tools and a bovine serum albumin (BSA) reference sample were shared among 67 laboratories, generating 129 comprehensive data sets. These allowed for an assessment of many parameters of instrument performance, including accuracy of the reported scan time after the start of centrifugation, the accuracy of the temperature calibration, and the accuracy of the radial magnification. The range of sedimentation coefficients obtained for BSA monomer in different instruments and using different optical systems was from 3.655 S to 4.949 S, with a mean and standard deviation of (4.304 ± 0.188) S (4.4%). After the combined application of correction factors derived from the external calibration references for elapsed time, scan velocity, temperature, and radial magnification, the range of s-values was reduced 7-fold with a mean of 4.325 S and a 6-fold reduced standard deviation of ± 0.030 S (0.7%). In addition, the large data set provided an opportunity to determine the instrument-to-instrument variation of the absolute radial positions reported in the scan files, the precision of photometric or refractometric signal magnitudes, and the precision of the calculated apparent molar mass of BSA monomer and the fraction of BSA dimers. These results highlight the necessity and effectiveness of independent calibration of basic AUC data dimensions for reliable quantitative studies

    A multilaboratory comparison of calibration accuracy and the performance of external references in analytical ultracentrifugation.

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    Analytical ultracentrifugation (AUC) is a first principles based method to determine absolute sedimentation coefficients and buoyant molar masses of macromolecules and their complexes, reporting on their size and shape in free solution. The purpose of this multi-laboratory study was to establish the precision and accuracy of basic data dimensions in AUC and validate previously proposed calibration techniques. Three kits of AUC cell assemblies containing radial and temperature calibration tools and a bovine serum albumin (BSA) reference sample were shared among 67 laboratories, generating 129 comprehensive data sets. These allowed for an assessment of many parameters of instrument performance, including accuracy of the reported scan time after the start of centrifugation, the accuracy of the temperature calibration, and the accuracy of the radial magnification. The range of sedimentation coefficients obtained for BSA monomer in different instruments and using different optical systems was from 3.655 S to 4.949 S, with a mean and standard deviation of (4.304 ± 0.188) S (4.4%). After the combined application of correction factors derived from the external calibration references for elapsed time, scan velocity, temperature, and radial magnification, the range of s-values was reduced 7-fold with a mean of 4.325 S and a 6-fold reduced standard deviation of ± 0.030 S (0.7%). In addition, the large data set provided an opportunity to determine the instrument-to-instrument variation of the absolute radial positions reported in the scan files, the precision of photometric or refractometric signal magnitudes, and the precision of the calculated apparent molar mass of BSA monomer and the fraction of BSA dimers. These results highlight the necessity and effectiveness of independent calibration of basic AUC data dimensions for reliable quantitative studies

    Acarbose improves health and lifespan in aging HET3 mice

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    To follow‐up on our previous report that acarbose (ACA), a drug that blocks postprandial glucose spikes, increases mouse lifespan, we studied ACA at three doses: 400, 1,000 (the original dose), and 2,500 ppm, using genetically heterogeneous mice at three sites. Each dose led to a significant change (by log‐rank test) in both sexes, with larger effects in males, consistent with the original report. There were no significant differences among the three doses. The two higher doses produced 16% or 17% increases in median longevity of males, but only 4% or 5% increases in females. Age at the 90th percentile was increased significantly (8%–11%) in males at each dose, but was significantly increased (3%) in females only at 1,000 ppm. The sex effect on longevity is not explained simply by weight or fat mass, which were reduced by ACA more in females than in males. ACA at 1,000 ppm reduced lung tumors in males, diminished liver degeneration in both sexes and glomerulosclerosis in females, reduced blood glucose responses to refeeding in males, and improved rotarod performance in aging females, but not males. Three other interventions were also tested: ursolic acid, 2‐(2‐hydroxyphenyl) benzothiazole (HBX), and INT‐767; none of these affected lifespan at the doses tested. The acarbose results confirm and extend our original report, prompt further attention to the effects of transient periods of high blood glucose on aging and the diseases of aging, including cancer, and should motivate studies of acarbose and other glucose‐control drugs in humans.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/148418/1/acel12898.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148418/2/acel12898_am.pd

    Meals in western eating and drinking

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    Meals are a way of organizing eating into events that have a particular structure and form, and they play an indisputable and even self-evident role within the rhythms and routines of everyday life. In late modern societies, concern about the fate of meals has arisen in both public and academic discourse. It has been suggested that eating is characterized today by individualization, destructuration, and informalization and that communal meals are increasingly being replaced by snacks and solitary eating. This chapter focuses on meals in today’s affluent societies and reflects on why meals are considered important, how meals are defined, and what material elements and social dimensions they contain. It looks at how societal and cultural changes and ecological concerns may influence the organization and future of meals, and it suggests that the content of meals will change in response to the need to diminish the ecological burden of food production and consumption. In particular, plant-based options will at least partly need to replace meat and other animal-based foods. However, there is no reason to expect that the meal as a social institution will break down. Despite the fact that not all meals are characterized by conviviality and companionship, they continue to serve as a significant arena of human sociability and togetherness. Sharing food is, after all, an essential part of being human.Non peer reviewe

    2013 Review and Update of the Genetic Counseling Practice Based Competencies by a Task Force of the Accreditation Council for Genetic Counseling

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    The first practice based competencies (PBCs) for the field of genetic counseling were adopted by the American Board of Genetic Counseling (ABGC), 1996. Since that time, there has been significant growth in established and new work settings (clinical and non‐clinical) and changes in service delivery models and the roles of genetic counselors. These changes prompted the ABGC to appoint a PBC Task Force in 2011 to review the PBCs with respect to their current relevance and to revise and update them as necessary. There are four domains in the revised PBCs: (I) Genetics Expertise and Analysis (II) Interpersonal, Psychosocial and Counseling Skills (III) Education and (IV) Professional Development and Practice. There are 22 competencies, each clarified with learning objectives or samples of activities and skills; a glossary is included. New competencies were added that address genomics, genetic testing and genetic counselors’ roles in risk assessment, education, supervision, conducting research and presenting research options to patients. With PBCs serving as the pre‐defined abilities or outcomes of training, graduating genetic counselors will be well prepared to enter the field with a minimum level of skills and abilities. A description of the Task Force’s work, key changes and the 2013 PBCs are presented herein.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147172/1/jgc40868.pd
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