Quantification of Cellular Proliferation in Acne Using the Monoclonal Antibody Ki-67

The mechanism by which ductal hypercornification occurs in acne is uncertain. We investigated proliferation in normal and acne follicles and in the interfollicular epidermis using the monoclonal antibody Ki-67, which reacts with a nuclear antigen expressed by cells in the G1, S, M, and G2 phases of the cell cycle. Cryostat sections of biopsies from the interscapular region from acne patients and from normal volunteers were stained with Ki-67 antibody and counterstained with 2% methyl green. The number of Ki-67-positive nuclei in the basal layer were counted and expressed as a percentage of the total number of basal nuclei in the ductal or interfollicular epithelia. The data was expressed as mean percent ± SD. In normal follicles from acne-affected sites 17.40% ± 1.86% (n = 8) of the nuclei were Ki-67 positive. This was significantly higher (p <0.01) than follicles from an area of skin unaffected by acne (11.01% ± 6.16%, n = 8). In the follicular epithelia of non-inflamed lesions, the percentage of Ki-67 positive nuclei was 23.44% ± 8.36% (n = 15). It was impossible to count the nuclei of follicular epithelium of inflamed lesions because little of this remained intact. In normal interfollicular epidermis, Ki-67-positive nuclei represented 5.33% ± 3.36% (n = 8) of the total. This value was not significantly different from the value obtained for interfollicular epidermis near non-inflamed lesions (10.46% ± 4.45%, n = 15). However, the number of Ki- 67-positive nuclei in the interfollicular epidermis near inflamed lesions was significantly higher than either of these two values: 25.26% ± 6.83%, n = 13, p < 0.05. Our results with Ki-67 confirm that ductal hyperproliferation occurs in acne and shows that normal follicles from acne skin may be “acne-prone.

Optimizing MRI sequences and images for MRI-based stereotactic radiosurgery treatment planning

© 2018 Aim: Development of MRI sequences and processing methods for the production of images appropriate for direct use in stereotactic radiosurgery (SRS) treatment planning. Background: MRI is useful in SRS treatment planning, especially for patients with brain lesions or anatomical targets that are poorly distinguished by CT, but its use requires further refinement. This methodology seeks to optimize MRI sequences to generate distortion-free and clinically relevant MR images for MRI-only SRS treatment planning. Materials and methods: We used commercially available SRS MRI-guided radiotherapy phantoms and eight patients to optimize sequences for patient imaging. Workflow involved the choice of correct MRI sequence(s), optimization of the sequence parameters, evaluation of image quality (artifact free and clinically relevant), measurement of geometrical distortion, and evaluation of the accuracy of our offline correction algorithm. Results: CT images showed a maximum deviation of 1.3 mm and minimum deviation of 0.4 mm from true fiducial position for SRS coordinate definition. Interestingly, uncorrected MR images showed maximum deviation of 1.2 mm and minimum of 0.4 mm, comparable to CT images used for SRS coordinate definition. After geometrical correction, we observed a maximum deviation of 1.1 mm and minimum deviation of only 0.3 mm. Conclusion: Our optimized MRI pulse sequences and image correction technique show promising results; MR images produced under these conditions are appropriate for direct use in SRS treatment planning

Redistribution of Health Care Costs after the Adoption of Positron Emission Tomography among Medicare Beneficiaries with Non–Small-Cell Lung Cancer, 1998–2005

INTRODUCTION: Treatment patterns and cost implications of increased positron emission tomography imaging use since Medicare approval in 1998 are not well understood. We examined rates of surgery, radiotherapy, and chemotherapy and inpatient and total health care costs between 1998 and 2005 among Medicare beneficiaries with non-small-cell lung cancer. METHODS: Patients in this retrospective cohort study were 51,374 Medicare beneficiaries diagnosed with non-small-cell lung cancer between 1996 and 2005. The main outcome measures were receipt of surgical resection, radiotherapy, and chemotherapy and inpatient and total health care costs within 1 year of diagnosis. RESULTS: Between 1996-1997 and 2004-2005, the proportion of patients undergoing surgical resection decreased from 29% to 25%, the proportion receiving radiation therapy decreased from 49% to 43%, and inpatient costs decreased from $28,900 to$26,900. The proportion of patients receiving chemotherapy increased from 25% to 40% and total costs increased from $47,300 to$52,200 (p < 0.001 for all comparisons). Changes in use and costs remained after adjustment for shifting demographic characteristics during the study period. CONCLUSIONS: Adoption of positron emission tomography between 1998 and 2005 was accompanied by decreases in rates of surgery and radiotherapy and in short-term inpatient costs among Medicare beneficiaries with non-small-cell lung cancer, although there was an increase in chemotherapy and overall costs

Pitfalls of Professionalism? Military Academies and Coup Risk

Military academies tend to be strongly linked to the professionalization of the armed forces. This explains why many countries in the world have created such institutions. The following article studies a potential negative externality stemming from military schools: increased coup risk. We argue that military academies may create, inculcate, and strengthen cohesive views that could conflict with incumbent policies, and that these schools establish networks among military officers that may facilitate coordination necessary for plotting a putsch. We also contend and empirically demonstrate that these negative side effects of military academies are in particular pronounced in nondemocracies, that is, military academies have diverse effects across regime types. This work has significant implications for our understanding civil–military relations. Furthermore, we contribute to the literature on military education and professionalization, as we suggest that military academies are important vehicles through which coups can emerge predominantly in authoritarian states

Planetary Candidates Observed by Kepler. VIII. A Fully Automated Catalog With Measured Completeness and Reliability Based on Data Release 25

We present the Kepler Object of Interest (KOI) catalog of transiting exoplanets based on searching four years of Kepler time series photometry (Data Release 25, Q1-Q17). The catalog contains 8054 KOIs of which 4034 are planet candidates with periods between 0.25 and 632 days. Of these candidates, 219 are new and include two in multi-planet systems (KOI-82.06 and KOI-2926.05), and ten high-reliability, terrestrial-size, habitable zone candidates. This catalog was created using a tool called the Robovetter which automatically vets the DR25 Threshold Crossing Events (TCEs, Twicken et al. 2016). The Robovetter also vetted simulated data sets and measured how well it was able to separate TCEs caused by noise from those caused by low signal-to-noise transits. We discusses the Robovetter and the metrics it uses to sort TCEs. For orbital periods less than 100 days the Robovetter completeness (the fraction of simulated transits that are determined to be planet candidates) across all observed stars is greater than 85%. For the same period range, the catalog reliability (the fraction of candidates that are not due to instrumental or stellar noise) is greater than 98%. However, for low signal-to-noise candidates between 200 and 500 days around FGK dwarf stars, the Robovetter is 76.7% complete and the catalog is 50.5% reliable. The KOI catalog, the transit fits and all of the simulated data used to characterize this catalog are available at the NASA Exoplanet Archive.Comment: 61 pages, 23 Figures, 9 Tables, Accepted to The Astrophysical Journal Supplement Serie

Ernst Freund as Precursor of the Rational Study of Corporate Law

Gindis, David, Ernst Freund as Precursor of the Rational Study of Corporate Law (October 27, 2017). Journal of Institutional Economics, Forthcoming. Available at SSRN: https://ssrn.com/abstract=2905547, doi: https://dx.doi.org/10.2139/ssrn.2905547The rise of large business corporations in the late 19th century compelled many American observers to admit that the nature of the corporation had yet to be understood. Published in this context, Ernst Freund's little-known The Legal Nature of Corporations (1897) was an original attempt to come to terms with a new legal and economic reality. But it can also be described, to paraphrase Oliver Wendell Holmes, as the earliest example of the rational study of corporate law. The paper shows that Freund had the intuitions of an institutional economist, and engaged in what today would be called comparative institutional analysis. Remarkably, his argument that the corporate form secures property against insider defection and against outsiders anticipated recent work on entity shielding and capital lock-in, and can be read as an early contribution to what today would be called the theory of the firm.Peer reviewe