Donnelly Breen (openhill9)
The physiological considerations for each of the techniques along with advantages and disadvantages are briefly discussed. © 2020 American Physiological Society. Compr Physiol 101155-1205, 2020.Islet cell replacement therapies represent an effective way to restore physiologic glycemic control in patients with type 1 diabetes (T1DM) and severe hypoglycemia. Despite being able to provide long-term insulin independence, patients still require lifelong immunosuppression, which has myriad detrimental effects including an increased risk for opportunistic infections and some types of cancer. This vital issue precludes widespread application of these therapies as a true cure for T1DM. Encapsulation of islets into immunoisolating/immunoprotective devices provides the potential of abrogating the requisite for lifelong immunosuppression. The field of cellular encapsulation lies at a complex intersection between the areas of chemistry, physics, bioengineering, cell biology, immunology, and clinical medicine. In diabetes, cellular encapsulation has existed for nearly 50 years, nevertheless, a resurgence of interest in the field has been motivated by promising results in small- and large-animal models. Recent studies have demonstrated that long-term diabetes reversal without immunosuppression is indeed routinely achievable. Future researchers interested in exploring cellular encapsulation strategies will require a clear understanding of the basic theoretical and practical principles, guiding this rapidly expanding field. This article will provide essential considerations concerning the physicochemical properties of the most commonly used biomaterials, relevant aspects of the immune response to bioencapsulation, current encapsulation strategies, potential implantation sites for encapsulated cell therapies and, finally, a comprehensive review on the current state of clinical translation. © 2020 American Physiological Society. Compr Physiol 10839-878, 2020.This article will discuss in detail the pathophysiology of asthma from the point of view of lung mechanics. In particular, we will explain how asthma is more than just airflow limitation resulting from airway narrowing but in fact involves multiple consequences of airway narrowing, including ventilation heterogeneity, airway closure, and airway hyperresponsiveness. In addition, the relationship between the airway and surrounding lung parenchyma is thought to be critically important in asthma, especially as related to the response to deep inspiration. Furthermore, dynamic changes in lung mechanics over time may yield important information about asthma stability, as well as potentially provide a window into future disease control. All of these features of mechanical properties of the lung in asthma will be explained by providing evidence from multiple investigative methods, including not only traditional pulmonary function testing but also more sophisticated techniques such as forced oscillation, multiple breath nitrogen washout, and different imaging modalities. Throughout the article, we will link the lung mechanical features of asthma to clinical manifestations of asthma symptoms, severity, and control. © 2020 American Physiological Society. Compr Physiol 10975-1007, 2020.The anatomy and physiology of the microcirculation in human skin are complex. Normal cutaneous microcirculation is organized in two parallel plexuses with capillary loops extending perpendicularly from the superficial plexus. The physiological regulation of cutaneous microcirculation includes specific sympathetic activation, which causes vasoconstriction through the release of norepinephrine, neuropeptide Y, and ATP. A sympathetic cholinergic system is mainly involved in vasodilation through the co-transmission of acetylcholine, vasoactive intestinal peptide, and pituitary adenylate cyclase-activating peptide. Sensory nerves play a major role through the release of calcitonin gene-related peptide and substance P. Endothe
