Classification of rib fracture types from postmortem computed tomography images using deep learning

Human or time resources can sometimes fall short in medical image diagnostics, and analyzing images in full detail can be a challenging task. With recent advances in artificial intelligence, an increasing number of systems have been developed to assist clinicians in their work. In this study, the objective was to train a model that can distinguish between various fracture types on different levels of hierarchical taxonomy and detect them on 2D-image representations of volumetric postmortem computed tomography (PMCT) data. We used a deep learning model based on the ResNet50 architecture that was pretrained on ImageNet data, and we used transfer learning to fine-tune it to our specific task. We trained our model to distinguish between “displaced,” “nondisplaced,” “ad latus,” “ad longitudinem cum contractione,” and “ad longitudinem cum distractione” fractures. Radiographs with no fractures were correctly predicted in 95–99% of cases. Nondisplaced fractures were correctly predicted in 80–86% of cases. Displaced fractures of the “ad latus” type were correctly predicted in 17–18% of cases. The other two displaced types of fractures, “ad longitudinem cum contractione” and “ad longitudinem cum distractione,” were correctly predicted in 70–75% and 64–75% of cases, respectively. The model achieved the best performance when the level of hierarchical taxonomy was high, while it had more difficulties when the level of hierarchical taxonomy was lower. Overall, deep learning techniques constitute a reliable solution for forensic pathologists and medical practitioners seeking to reduce workload

Ventilation and Perfusion at the Alveolar Level: Insights From Lung Intravital Microscopy

Intravital microscopy (IVM) offers unique possibilities for the observation of biological processes and disease related mechanisms in vivo. Especially for anatomically complex and dynamic organs such as the lung and its main functional unit, the alveolus, IVM provides exclusive advantages in terms of spatial and temporal resolution. By the use of lung windows, which have advanced and improved over time, direct access to the lung surface is provided. In this review we will discuss two main topics, namely alveolar dynamics and perfusion from the perspective of IVM-based studies. Of special interest are unanswered questions regarding alveolar dynamics such as: What are physiologic alveolar dynamics? How do these dynamics change under pathologic conditions and how do those changes contribute to ventilator-induced lung injury? How can alveolar dynamics be targeted in a beneficial way? With respect to alveolar perfusion IVM has propelled our understanding of the pulmonary microcirculation and its perfusion, as well as pulmonary vasoreactivity, permeability and immunological aspects. Whereas the general mechanism behind these processes are understood, we still lack a proper understanding of the complex, multidimensional interplay between alveolar ventilation and microvascular perfusion, capillary recruitment, or vascular immune responses under physiologic and pathologic conditions. These are only part of the unanswered questions and problems, which we still have to overcome. IVM as the tool of choice might allow us to answer part of these questions within the next years or decades. As every method, IVM has advantages as well as limitations, which have to be taken into account for data analysis and interpretation, which will be addressed in this review

Formulation, Delivery and Stability of Bone Morphogenetic Proteins for Effective Bone Regeneration

Drug Delivery Technolog

Development Of A Novel Cardiac Ischemia-Reperfusion Model In The Axolotl

The Center for Disease Control’s National Center for Health Statistics data for mortality from diseases of the heart show the age-adjusted death rate has fallen from almost 600 deaths in the 1950s to just over 190 deaths per 100,000 U.S. residents today. With the recognized limitations of pharmacotherapy of myocardial infarction (MI), cell-based therapies have been undergoing rapid development and clinical testing. However, there is still no consensus about cell types, delivery routes, dosing and treatment schedules and pretreatment conditioning of cells prior to administration. Furthermore, a fundamental question remains unanswered about the reasons for the poor capacity for myocardial tissue regeneration in humans (mammals in general) as compared to robust myocardial regeneration in lower vertebrates (i.e., axolotl [Ambystoma mexicanum] and zebrafish [Danio rerio]). This lack in understanding the mechanisms behind the cell-cycle of cardiomyocytes and or cardiac progenitor cells, both during times of normal homeostasis and after pathologic insults, is central to the lack of progress in stimulating the regeneration of cardiac tissue. To understand the differences in cardiac tissue response after an MI, developing a true model of ischemia-reperfusion injury in an animal known for epimorphic regeneration in the adult life stage will help reframe the direction of research in the field of tissue engineering and regenerative medicine in the field of cardiology. To understand how the axolotl will respond to an MI, this research focuses on two Specific Aims: Specific Aim 1: Develop a cardiac injury model in the axolotl that mimics the pathophysiology of a myocardial infarction in the mammalian heart. Cardiac injury models used to study heart regeneration in lower vertebrates known for robust healing responses have used novel approaches to induce major cardiomyocyte death. However, these novel injury models do not recapitulate the cellular signaling mechanisms present during ischemia and ischemia-reperfusion injuries. Thus, to study the epimorphic regeneration of heart tissue in axolotls, a novel model of inducing ischemia needs to be developed. Specific Aim 2: Determine the spatiotemporal progression of axolotl cardiac tissue histopathology over time. Once a novel cardiac injury model produces the expected pathophysiological tissue response, chronic follow-up of surviving animals will help develop the spatiotemporal response to an MI. Data on functional recovery will require the development of regular, non-invasive techniques for monitoring heart function. After long-term recovery, appropriate harvesting of heart samples for histologic study is required to determine if the axolotl can completely regenerate cardiac injuries after an MI

Distribution and variability study of the femur cortical thickness from computer tomography

In the context of patient-specific 3D bone reconstruction, enhancing the surface with cortical thickness (COT) opens a large field of applications for research and medicine. This functionality calls for database analysis for better knowledge of COT. Our study provides a new approach to reconstruct 3D internal and external cortical surfaces from computer tomography (CT) scans and analyses COT distribution and variability on a set of asymptomatic femurs. The reconstruction method relies on a short (∼5 min) initialisation phase based on 3D reconstruction from biplanar CT-based virtual X-rays and an automatic optimisation phase based on intensity-based cortical structure detection in the CT volume, the COT being the distance between internal and external cortical surfaces. Surfaces and COT show root mean square reconstruction errors below 1 and 1.3 mm. Descriptions of the COT distributions by anatomical regions are provided and principal component analysis has been applied. The first mode, 16–50% of the variance, corresponds to the variation of the mean COT around its averaged shape; the second mode, 9–28%, corresponds to a fine variation of its shape. A femur COT model can, therefore, be described as the averaged COT distribution in which the first parameter adjusts its mean value and a second parameter adjusts its shape

Maternal Guilt: An Existential Phenomenological Study of the Early Experiences of First-Time Mothers

The present study is an existential phenomenological investigation of the experiences of maternal guilt of five first-time mothers with infant children. Maternal guilt is a powerful, pervasive, and complex phenomenon that effects and is experienced by mothers in different ways. This research explores the experiences of these five mothers in feeling guilt related to being a mother and, using an adapted research methodology utilizing Focusing Technique (Gendlin, 1981), their embodied reflections about a particular memory of feeling maternal guilt. This study utilizes procedures explicated by Colaizzi (1978), Giorgi & Giorgi (2003), Todres (2007), von Eckartsberg (1998), Walsh (1995; 2004) and Wertz (1984). All participants provided data via a written account of a particular memory of feeling a sense of guilt related to being a mother, an individual interview which incorporated a modified Focusing component, and written and verbal feedback related to the write-up of the provisional thematic analysis of the interview. The interpreted analyses of the five interviews indicate seven formulated themes; physical and emotional connection to their babies, intense feelings of responsibility, feelings of being divided, multi-dimensionality of guilt with other emotions, pre-verbal miscommunication, anxiety over the unknown in the beginning, and social expectations and comparisons. The findings suggest that the process of embodied reflection regarding a new mother\u27s emotional experiences of guilt can foster important awareness for how she can care for her own and her child\u27s needs. Relationships between contemporary cultural discourses on motherhood and philosophical interpretations of guilt are discussed. Implications for creating networks of support and community for new parents are also explored