Introduction to Environmental Biodynamics

2021 ◽  
pp. 1-21
Author(s):  
Manish Arora ◽  
Paul Curtin ◽  
Austen Curtin ◽  
Christine Austin ◽  
Alessandro Giuliani

Chapter 1 outlines the axioms of the biodynamic interface conjecture, each of which are detailed in subsequent chapters. It is shown that in order to properly identify and characterize any dynamic system, it is necessary to identify more than a few isolated “things” making up the pattern. Rather, one must know the sequence of events and the organization of the system in order to understand and recognize its function in both space and time. In essence, Environmental Biodynamics seeks to understand how the environment and human physiology interact through a focus on functional interfaces; specifically the focus is on the patterns that emerge in the integration of the environment into human physiology rather than on isolated “snapshots” taken in passing.

Author(s):  
K. Kovacs ◽  
E. Horvath ◽  
J. M. Bilbao ◽  
F. A. Laszlo ◽  
I. Domokos

Electrolytic lesions of the pituitary stalk in rats interrupt adenohypophysial blood flow and result in massive infarction of the anterior lobe. In order to obtain a deeper insight into the morphogenesis of tissue injury and to reveal the sequence of events, a fine structural investigation was undertaken on adenohypophyses of rats at various intervals following destruction of the pituitary stalk.The pituitary stalk was destroyed electrolytically, with a Horsley-Clarke apparatus on 27 male rats of the R-Amsterdam strain, weighing 180-200 g. Thirty minutes, 1,2,4,6 and 24 hours after surgery the animals were perfused with a glutaraldehyde-formalin solution. The skulls were then opened and the pituitary glands removed. The anterior lobes were fixed in glutaraldehyde-formalin solution, postfixed in osmium tetroxide and embedded in Durcupan. Ultrathin sections were stained with uranyl acetate and lead citrate and investigated with a Philips 300 electron microscope.


Author(s):  
L.X. Oakford ◽  
S.D. Dimitrijevich ◽  
R. Gracy

In intact skin the epidermal layer is a dynamic tissue component which is maintained by a basal layer of mitotically active cells. The protective upper epidermis, the stratum corneum, is generated by differentiation of the suprabasal keratinocytes which eventually desquamate as anuclear comeocytes. A similar sequence of events is observed in vitro in the non-contracting human skin equivalent (HSE) which was developed in this lab (1). As a part of the definition process for this model of living skin we are examining its ultrastructural features. Since desmosomes are important in maintaining cell-cell interactions in stratified epithelia their distribution in HSE was examined.


Author(s):  
L. J. Brenner ◽  
D. G. Osborne ◽  
B. L. Schumaker

Exposure of the ciliate, Tetrahymena pyriformis, strain WH6, to normal human or rabbit sera or mouse ascites fluids induces the formation of large cytoplasmic bodies. By electron microscopy these (LB) are observed to be membrane-bounded structures, generally spherical and varying in size (Fig. 1), which do not resemble the food vacuoles of cells grown in proteinaceous broth. The possibility exists that the large bodies represent endocytic vacuoles containing material concentrated from the highly nutritive proteins and lipoproteins of the sera or ascites fluids. Tetrahymena mixed with bovine serum albumin or ovalbumin solutions having about the same protein concentration (7g/100 ml) as serum form endocytic vacuoles which bear little resemblance to the serum-induced LB. The albumin-induced structures (Fig. 2) are irregular in shape, rarely spherical, and have contents which vary in density and consistency. In this paper an attempt is made to formulate the sequence of events which might occur in the formation of the albumin-induced vacuoles.


2014 ◽  
Vol 56 ◽  
pp. 99-110 ◽  
Author(s):  
David Allsop ◽  
Jennifer Mayes

One of the hallmarks of AD (Alzheimer's disease) is the formation of senile plaques in the brain, which contain fibrils composed of Aβ (amyloid β-peptide). According to the ‘amyloid cascade’ hypothesis, the aggregation of Aβ initiates a sequence of events leading to the formation of neurofibrillary tangles, neurodegeneration, and on to the main symptom of dementia. However, emphasis has now shifted away from fibrillar forms of Aβ and towards smaller and more soluble ‘oligomers’ as the main culprit in AD. The present chapter commences with a brief introduction to the disease and its current treatment, and then focuses on the formation of Aβ from the APP (amyloid precursor protein), the genetics of early-onset AD, which has provided strong support for the amyloid cascade hypothesis, and then on the development of new drugs aimed at reducing the load of cerebral Aβ, which is still the main hope for providing a more effective treatment for AD in the future.


2000 ◽  
Vol 5 (5) ◽  
pp. 4-5

Abstract Spinal cord (dorsal column) stimulation (SCS) and intraspinal opioids (ISO) are treatments for patients in whom abnormal illness behavior is absent but who have an objective basis for severe, persistent pain that has not been adequately relieved by other interventions. Usually, physicians prescribe these treatments in cancer pain or noncancer-related neuropathic pain settings. A survey of academic centers showed that 87% of responding centers use SCS and 84% use ISO. These treatments are performed frequently in nonacademic settings, so evaluators likely will encounter patients who were treated with SCS and ISO. Does SCS or ISO change the impairment associated with the underlying conditions for which these treatments are performed? Although the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides) does not specifically address this question, the answer follows directly from the principles on which the AMA Guides impairment rating methodology is based. Specifically, “the impairment percents shown in the chapters that consider the various organ systems make allowance for the pain that may accompany the impairing condition.” Thus, impairment is neither increased due to persistent pain nor is it decreased in the absence of pain. In summary, in the absence of complications, the evaluator should rate the underlying pathology or injury without making an adjustment in the impairment for SCS or ISO.


2000 ◽  
Vol 5 (6) ◽  
pp. 1-7
Author(s):  
Christopher R. Brigham ◽  
James B. Talmage ◽  
Leon H. Ensalada

Abstract The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fifth Edition, is available and includes numerous changes that will affect both evaluators who and systems that use the AMA Guides. The Fifth Edition is nearly twice the size of its predecessor (613 pages vs 339 pages) and contains three additional chapters (the musculoskeletal system now is split into three chapters and the cardiovascular system into two). Table 1 shows how chapters in the Fifth Edition were reorganized from the Fourth Edition. In addition, each of the chapters is presented in a consistent format, as shown in Table 2. This article and subsequent issues of The Guides Newsletter will examine these changes, and the present discussion focuses on major revisions, particularly those in the first two chapters. (See Table 3 for a summary of the revisions to the musculoskeletal and pain chapters.) Chapter 1, Philosophy, Purpose, and Appropriate Use of the AMA Guides, emphasizes objective assessment necessitating a medical evaluation. Most impairment percentages in the Fifth Edition are unchanged from the Fourth because the majority of ratings currently are accepted, there is limited scientific data to support changes, and ratings should not be changed arbitrarily. Chapter 2, Practical Application of the AMA Guides, describes how to use the AMA Guides for consistent and reliable acquisition, analysis, communication, and utilization of medical information through a single set of standards.


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