Steroid induced osteonecrosis: An analysis of steroid dosing risk.

Osteonecrosis is a serious condition involving bone destruction that frequently requires surgical treatment to rebuild the joint. While there is an abundance of literature documenting corticosteroid related osteonecrosis, there is no consensus as to the relative risk of osteonecrosis after administration of steroids via parenteral, oral, topical, inhaled and other routes. This risk is an important prognostic indicator because identification and conservative intervention can potentially reduce morbidity associated with aggressive surgical treatment of osteonecrosis. This paper provides insight into establishing guidelines related to the risk of developing osteonecrosis as a result of corticosteroid use. Case studies, retrospective studies and prospective studies in humans on different corticosteroids and varied dosages were assessed. Most cases of osteonecrosis are secondary to systemically administered corticosteroids and/or high dose daily therapy, particularly in patients with underlying comorbidities including connective tissue diseases, hyperlipidemia, or previous trauma. Previous case reports of osteonecrosis related to inhaled or topical use of steroids are complicated by the fact that in the great majority of cases, the patients are also treated with systemic steroids prior to the development of osteonecrosis. Based on the literature, a set of recommendations regarding the risk of osteonecrosis in patients on steroids was formulated

Brain-Blood Partition Coefficient and Cerebral Blood Flow in Canines Using Calibrated Short TR Recovery (CaSTRR) Correction Method.

The brain-blood partition coefficient (BBPC) is necessary for quantifying cerebral blood flow (CBF) when using tracer based techniques like arterial spin labeling (ASL). A recent improvement to traditional MRI measurements of BBPC, called calibrated short TR recovery (CaSTRR), has demonstrated a significant reduction in acquisition time for BBPC maps in mice. In this study CaSTRR is applied to a cohort of healthy canines (n = 17, age = 5.0 - 8.0 years) using a protocol suited for application in humans at 3T. The imaging protocol included CaSTRR for BBPC maps, pseudo-continuous ASL for CBF maps, and high resolution anatomical images. The standard CaSTRR method of normalizing BBPC to gadolinium-doped deuterium oxide phantoms was also compared to normalization using hematocrit (Hct) as a proxy value for blood water content. The results show that CaSTRR is able to produce high quality BBPC maps with a 4 min acquisition time. The BBPC maps demonstrate significantly higher BBPC in gray matter (0.83 ± 0.05 mL/g) than in white matter (0.78 ± 0.04 mL/g, p = 0.006). Maps of CBF acquired with pCASL demonstrate a negative correlation between gray matter perfusion and age (p = 0.003). Voxel-wise correction for BBPC is also shown to improve contrast to noise ratio between gray and white matter in CBF maps. A novel aspect of the study was to show that that BBPC measurements can be calculated based on the known Hct of the blood sample placed in scanner. We found a strong correlation (R 2 = 0.81 in gray matter, R 2 = 0.59 in white matter) established between BBPC maps normalized to the doped phantoms and BBPC maps normalized using Hct. This obviates the need for doped water phantoms which simplifies both the acquisition protocol and the post-processing methods. Together this suggests that CaSTRR represents a feasible, rapid method to account for BBPC variability when quantifying CBF. As canines have been used widely for aging and Alzheimer's disease studies, the CaSTRR method established in the animals may further improve CBF measurements and advance our understanding of cerebrovascular changes in aging and neurodegeneration

A Model of Learning for Research in Information Systems Education

Educational researchers have long studied the role of the student in educational settings with the goal of improving learning outcomes. In this paper, we review constructs commonly employed in studies reported in the education literature undertaken to better understand how and why people learn. We then incorporate these constructs into a model of learning that we hope can be utilized as a starting point in further research in information systems education

Teacher, Advocate, Friend: Remembering David Bederman

David Bederman was a superb teacher, a skilled advocate, and a gracious human being. The three of us saw each of these qualities firsthand when Professor Bederman invited us to work with him on a case he argued before the Supreme Court of the United States, Lapides v. Board of Regents of the University System of Georgia, while we were third-year law students

Helminth Parasites of Some Iowa Fishes

Individuals of 16 species of fishes representing the Centrarchidae, Ictaluridae, Catastomidae, Cyprinidae, Percidae, and Serranidae were collected at 8 localities in central and north-central Iowa, and examined for helminth parasites. Thirty-nine parasite species were recovered: 20 Monogenea, 8 Digenea, 3 Cestoda, 4 Acanthocephala, and 4 Nematoda. A new host record is reported for Gyrodactylus machrochiri from Lepomis humilis

Inflammatory Myofibroblastic Tumor: A Case Study

AbstractInflammatory myofibroblastic tumor (IMT) is a rare benign lesion found in many locations throughout the body and genitourinary tract. Endoscopically and radiographically, these solid lesions cannot be distinguished from malignant bladder tumors. We present the case of a 21-year-old woman who presented with painful obstructive and irritative voiding symptoms of short duration. After extensive preoperative evaluation failed to reveal a definitive diagnosis, the patient underwent partial cystectomy. Final pathology revealed IMT. A high index of suspicion is required for diagnosis of IMT as it is often difficult to distinguish from its malignant counterparts

Team strategic philosophy: requiem for the infinite game

Deliberate accountability has arrived in the medical arena, producing an age of reward for measured performance, and belief in publicizing metrics to ensure clarity, with winning defined as hitting targets, whereby staff are incentivised by arbitrary objectives. Finite game theory declares that players are known, rules are fixed, and the objective agreed, but infinite game theory asserts that players are both known and unknown, rules are changeable, and the objective is to perpetuate the game; these standards are clearly at odds and risk real world chaos in global universal medical education and clinical outcomes and functioning. Five principles are necessary to lead an infinite game: first, a fair basis, such that sacrifices for its advancement are promoted; second, a trusting blame-free team culture and environment; third, competitors viewed as worthy rivals, rather than adversaries, promoting healthy competition; fourth, existential flexibility when faced with credible evidence; and finally, transformational leadership; including infinite game theory into healthcare planning may be difficult, but the potential rewards are surely worth the existential fight

Introduction to empowered partnerships: community-based participatory action research for environmental justice

This article introduces a special section on empowered partnerships that deepens a dialogue initiated during the 2010 symposium titled EmPowered Partnerships: Community-Based Participatory Action Research for Environmental Justice. The articles in this section will be divided between issues 1 and 2 of the Journal. After briefly reviewing the definitions and the steps associated with community-based participatory action research (CBPAR), we identify the synergies connecting the underlying principles and values of the environmental justice (EJ) movement and CBPAR. The principles-based comparison is part of an ongoing effort to craft a framework that produces research partnerships that are simultaneously more responsive to community aspirations and increase the rigor and accuracy of the findings. The action step is among the most difficult challenges for both CBPAR and EJ processes; we address this challenge as we encourage partners to think more strategically about the role of law and legal scholarship. This article closes with insight from environmental justice leaders that participated in this symposium and introductions to the in-depth case studies in rural and urban settings and from both ends of the university- community partnerships that constitute this special section. The articles that make up this section unpack empowered partnerships in practice and explore the scientific, cultural, institutional, and democratic pitfalls and possibilities in this arena of inquiry and social action

Multi‐century stasis in C3 and C4 grass distributions across the contiguous United States since the industrial revolution

AimsUnderstanding the functional response of ecosystems to past global change is crucial to predicting performance in future environments. One sensitive and functionally significant attribute of grassland ecosystems is the percentage of species that use the C4 versus C3 photosynthetic pathway. Grasses using C3 and C4 pathways are expected to have different responses to many aspects of anthropogenic environmental change that have followed the industrial revolution, including increases in temperature and atmospheric CO2, changes to land management and fire regimes, precipitation seasonality, and nitrogen deposition. In spite of dramatic environmental changes over the past 300 years, it is unknown if the C4 grass percentage in grasslands has shifted.LocationContiguous United States of America.MethodsHere, we used stable carbon isotope data (i.e. δ13C) from 30 years of soil samples, as well as herbivore tissues that date to 1739 CE, to reconstruct coarse‐grain C3 and C4 grass composition in North American grassland sites to compare with modern vegetation. We spatially resampled these three datasets to a shared 100‐km grid, allowing comparison of δ13C values at a resolution and extent common for climate model outputs and biogeographical studies.ResultsAt this spatial grain, the bison tissue proxy was superior to the soil proxy because the soils reflect integration of local carbon inputs, whereas bison sample vegetation across landscapes. Bison isotope values indicate that historical grassland photosynthetic‐type composition was similar to modern vegetation.Main conclusionsDespite major environmental change, comparing modern plot vegetation data to three centuries of bison δ13C data revealed that the biogeographical distribution of C3 and C4 grasses has not changed significantly since the 1700s. This is particularly surprising given the expected CO2 fertilization of C3 grasses. Our findings highlight the critical importance of capturing the full range of physiological, ecological and demographical processes in biosphere models predicting future climates and ecosystems.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/139065/1/jbi13061.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139065/2/jbi13061_am.pd

Quantifying proliferative and surface marker heterogeneity in colony‐founding connective tissue progenitors and their progeny using time‐lapse microscopy

Connective tissue progenitors (CTPs) are defined as the heterogeneous population of tissue‐resident stem and progenitor cells that are capable of proliferating and differentiating into connective tissue phenotypes. The prevalence and variation in clonal progeny of CTPs can be characterized using a colony formation assay. However, colony assays do not directly assess the characteristics of the colony‐founding CTP. We performed large, field‐of‐view, time‐lapse microscopy to manually track colonies back to the founding cells. Image processing and analysis was used to characterize the colonies and their founding cells. We found that the traditional colony‐forming unit (CFU) assay underestimates the number of founding cells as colonies can be formed by more than one founding cell. After 6 days in culture, colonies do not completely express CD73, CD90, and CD105. Heterogeneity in colony cells was characterized by two cell populations, proliferative and spread cells. Regression modelling of duration of lag phase and doubling time by cell marker suggests the presence of CD90 and CD105 in CTP subpopulations with different proliferative capabilities. From mathematical modelling of clonal colonies, we quantitatively characterized proliferation, migration, and cell marker expression rates to identify desirable clones for selection. Direct assessment of colony formation parameters led to more accurate assessment of CFU heterogeneity. Furthermore, these parameters can be used to quantify the diversity and hierarchy of stem and progenitor cells from a cell source or tissue for tissue engineering applications