Structural Changes in Abdominal Aorta Wall at the Modeling of Long-Term Sympathicotonia on Laboratory Animals

This work covers current questions on studying structural changes in the wall of the abdominal aorta during the modelled long-term immobilization stress against vagotonia. The purpose of this study was to reveal the effect of prolonged vagotonia on the structure of the wall of the abdominal aorta in rats in the experiment. The studies were performed on three comparable groups of hundred-day Wistar rats, which were exposed to immobilization stress and vagotonia for a period of 10 days. Immobilization was chosen as a method to induce stress model. The rats were placed into a special plastic box, in this way limiting their movements for four hours at room temperature. Vagotonia was modelled by the administration of pyridostigmine bromide, reversible anticholinesterase. Histological preparations of the abdominal aorta were studied by x40, x100, x400 magnification using the Primo Star 5 microscope (Carl Zeiss, FRG) followed by photography of microscopic images. Computer morphometry was performed with x100 and x400 magnification and then the image were displayed on the computer monitor using the DVR and AxioVision image analysis software (Rel.4.8.2) in μm. We assessed the thickness of the subendothelial layer, and namely an internal elastic membrane and media. The ratio of the extent of the abdominal aorta lumen to the vascular wall was calculated in the Adobe Photoshop program by the A. A. Glagoliev method through overlaying of point grids on sections, the results were converted into percentages. The studies were carried out in five fields of five different sections in each rat. The results of the variation analysis of the morphological data obtained have revealed some features of restructuring the vascular wall of the abdominal aorta due to prolonged immobilization stress accompanied by vagotonia. It has been found out that prolonged exposure of hundred-day Wistar rats to immobilization stress leads to a decrease in thickness and certain morphological changes in all layers of the abdominal aorta wall and a decrease in the percentage of the component of the vessel wall. When accompanied by prolonged immobilization and vagotonia, preservation of the endothelial layer of the abdominal aorta was observed against the background of a decrease in intimal thickness and degenerative cell changes, as well as media thickening and focal changes in adventitia.

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Coming Together Through Falling Apart

Rorschachiana Journal of the International Society for the Rorschach ◽

10.1027/1192-5604/a000115 ◽

2019 ◽

Vol 40 (2) ◽

pp. 151-168

Author(s):

Heather Churchill ◽

Jeremy M. Ridenour

Keyword(s):

Data Analysis ◽

Qualitative Data ◽

Structural Changes ◽

Systematic Approach ◽

Qualitative Approach ◽

Psychological Assessments ◽

Transference And Countertransference ◽

Testing Data ◽

Psychoanalytically Oriented Psychotherapy

Abstract. Assessing change during long-term psychotherapy can be a challenging and uncertain task. Psychological assessments can be a valuable tool and can offer a perspective from outside the therapy dyad, independent of the powerful and distorting influences of transference and countertransference. Subtle structural changes that may not yet have manifested behaviorally can also be assessed. However, it can be difficult to find a balance between a rigorous, systematic approach to data, while also allowing for the richness of the patient’s internal world to emerge. In this article, the authors discuss a primarily qualitative approach to the data and demonstrate the ways in which this kind of approach can deepen the understanding of the more subtle or complex changes a particular patient is undergoing while in treatment, as well as provide more detail about the nature of an individual’s internal world. The authors also outline several developmental frameworks that focus on the ways a patient constructs their reality and can guide the interpretation of qualitative data. The authors then analyze testing data from a patient in long-term psychoanalytically oriented psychotherapy in order to demonstrate an approach to data analysis and to show an example of how change can unfold over long-term treatments.

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Anesthesia for rabbits submitted to experimental surgeries: Report of a series of eight anesthesias

Panorama brasileiro de tungstênio (w) entre os anos de 2008 e 2014 ◽

10.32749/nucleodoconhecimento.com.br/health/anesthesia-for-rabbits ◽

2020 ◽

pp. 151-158

Author(s):

Rafael Antonio Caldart Bedin ◽

Maisa Schultz ◽

Antonio Bedin

Keyword(s):

Muscle Relaxation ◽

Anesthetic Management ◽

Laboratory Animals ◽

Average Weight ◽

Anesthetic Induction ◽

Anesthetic Agents ◽

Reasonable Degree ◽

Bioethical Debate ◽

Precordial Stethoscope

Anesthesia for laboratory animals is a matter of biomedical concern and one of the most present dilemmas in the current bioethical debate. The use of anesthetic agents in experimental surgery aims at analgesia and restraining the animal, in order to achieve a reasonable degree of muscle relaxation and to produce sufficient analgesia. This practice requires the use of protocols for the administration of safe and efficient doses. Eight New Zealand rabbits were submitted to laparotomies demonstrating the surgical technique discipline of the local medical course. For pre-anesthetic medication, acepromazine 1 mg.kg-1 associated with ketamine 15 mg.kg-1 was used subcutaneously. Anesthesia was maintained with isoflurane and oxygen under a laryngeal mask in a Mapleson D anesthesia system and under spontaneous breathing. Hydration was performed with 10 ml.kg-1 saline every hour. A thermal mattress was used. Precordial stethoscope, pulse oximetry and clinical parameters were used for monitoring. For euthanasia, ketamine 10 mg.kg-1 associated with potassium chloride 19.1% 1 ml.kg-1 was used intravenously. The average weight of the rabbits was 2721.25 ± 275.01 grams and the duration of the anesthetic procedure was 120 ± 87 minutes. Discussion. In long-term anesthesia, such as laparotomies, the use of pre-anesthetic medication and then anesthetic induction by the combination of agents is recommended. However, anesthetic management requires monitoring to prevent insufficient or excessive doses from occurring.

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Economic Institutions and Growth Nexus: The Role of Governance and Democratic Institutions—Evidence from Time Varying Parameters’ (TVPs) Models

The Pakistan Development Review ◽

10.30541/v55i4i-iipp.675-688 ◽

2016 ◽

Vol 55 (4I-II) ◽

pp. 675-688

Author(s):

Ghulam Murtaza ◽

Muhammad Zahir Faridi

Keyword(s):

Structural Changes ◽

Jel Classification ◽

Economic Institutions ◽

Time Varying ◽

Democratic Institutions ◽

Main Hypothesis ◽

Dynamic Relationship ◽

Rolling Window

The present study has investigated the channels through which the linkage between economic institutions and growth is gauged, by addressing the main hypothesis of the study that whether quality of governance and democratic institutions set a stage for economic institutions to promote the long-term growth process in Pakistan. To test the hypothesis empirically, our study models the dynamic relationship between growth and economic institutions in a time varying framework in order to capture institutional developments and structural changes occurred in the economy of Pakistan over the years. Study articulates that, along with some customary specifics, the quality of government and democracy are the substantial factors that affect institutional quality and ultimately cause to promote growth in Pakistan. JEL Classification: O40; P16; C14; H10 Keywords: Economic Institutions, Growth, Governance and Democracy, Rolling Window Two-stage Least Squares, Pakistan

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Individual differences in white and grey matter structure associated with verbal habits of thought

10.31234/osf.io/ukgyr ◽

2019 ◽

Author(s):

Justin C. Hayes ◽

Katherine L Alfred ◽

Rachel Pizzie ◽

Joshua S. Cetron ◽

David J. M. Kraemer

Keyword(s):

Individual Differences ◽

White Matter ◽

Cognitive Processing ◽

Grey Matter ◽

Structural Changes ◽

Structural Integrity ◽

Diffusion Tensor ◽

Self Report ◽

White Matter Tracts

Modality specific encoding habits account for a significant portion of individual differences reflected in functional activation during cognitive processing. Yet, little is known about how these habits of thought influence long-term structural changes in the brain. Traditionally, habits of thought have been assessed using self-report questionnaires such as the visualizer-verbalizer questionnaire. Here, rather than relying on subjective reports, we measured habits of thought using a novel behavioral task assessing attentional biases toward picture and word stimuli. Hypothesizing that verbal habits of thought are reflected in the structural integrity of white matter tracts and cortical regions of interest, we used diffusion tensor imaging and volumetric analyses to assess this prediction. Using a whole-brain approach, we show that word bias is associated with increased volume in several bilateral language regions, in both white and grey matter parcels. Additionally, connectivity within white matter tracts within an a priori speech production network increased as a function of word bias. These results demonstrate long-term structural and morphological differences associated with verbal habits of thought.

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Structural changes in the metal of welded joints of long-term operating steam pipelines

Avtomatičeskaâ svarka (Kiev) ◽

10.37434/as2020.02.04 ◽

2020 ◽

Vol 2020 (2) ◽

pp. 24-28

Author(s):

V.V. Dmytryk ◽

◽

. A.V. Glushko ◽

S.P. Iglin ◽

◽

...

Keyword(s):

Welded Joints ◽

Structural Changes ◽

Operating Steam

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A New Classification for Pathologies of Spinal Meninges, Part 1: Dural Cysts, Dissections, and Ectasias

Neurosurgery ◽

10.1093/neuros/nyx049 ◽

2017 ◽

Vol 81 (1) ◽

pp. 29-44 ◽

Cited By ~ 8

Author(s):

Jörg Klekamp

Keyword(s):

Structural Changes ◽

Long Term Results ◽

Type I ◽

Type Ii ◽

New Classification ◽

Type Iii ◽

Dural Sac ◽

Spinal Cord Herniation ◽

Dural Defects

Abstract BACKGROUND: The clinical significance of pathologies of the spinal dura is often unclear and their management controversial. OBJECTIVE: To classify spinal dural pathologies analogous to vascular aneurysms, present their symptoms and surgical results. METHODS: Among 1519 patients with spinal space-occupying lesions, 66 patients demonstrated dural pathologies. Neuroradiological and surgical features were reviewed and clinical data analyzed. RESULTS: Saccular dural diverticula (type I, n = 28) caused by defects of both dural layers, dissections between dural layers (type II, n = 29) due to defects of the inner layer, and dural ectasias (type III, n = 9) related to structural changes of the dura were distinguished. For all types, symptoms consisted of local pain followed by signs of radiculopathy or myelopathy, while one patient with dural ectasia presented a low-pressure syndrome and 10 patients with dural dissections additional spinal cord herniation. Type I and type II pathologies required occlusion of their dural defects via extradural (type I) or intradural (type II) approaches. For type III pathologies of the dural sac no surgery was recommended. Favorable results were obtained in all 14 patients with type I and 13 of 15 patients with type II pathologies undergoing surgery. CONCLUSION: The majority of dural pathologies involving root sleeves remain asymptomatic, while those of the dural sac commonly lead to pain and neurological symptoms. Type I and type II pathologies were treated with good long-term results occluding their dural defects, while ectasias of the dural sac (type III) were managed conservatively.

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Visualizing the Bohr effect in hemoglobin: neutron structure of equine cyanomethemoglobin in the R state and comparison with human deoxyhemoglobin in the T state

Acta Crystallographica Section D Structural Biology ◽

10.1107/s2059798316009049 ◽

2016 ◽

Vol 72 (7) ◽

pp. 892-903 ◽

Cited By ~ 5

Author(s):

Steven Dajnowicz ◽

Sean Seaver ◽

B. Leif Hanson ◽

S. Zoë Fisher ◽

Paul Langan ◽

...

Keyword(s):

Structural Changes ◽

Accurate Determination ◽

Bohr Effect ◽

Salt Bridges ◽

Histidine Residues ◽

Regions Of Stability ◽

The Individual ◽

T State

Neutron crystallography provides direct visual evidence of the atomic positions of deuterium-exchanged H atoms, enabling the accurate determination of the protonation/deuteration state of hydrated biomolecules. Comparison of two neutron structures of hemoglobins, human deoxyhemoglobin (T state) and equine cyanomethemoglobin (R state), offers a direct observation of histidine residues that are likely to contribute to the Bohr effect. Previous studies have shown that the T-state N-terminal and C-terminal salt bridges appear to have a partial instead of a primary overall contribution. Four conserved histidine residues [αHis72(EF1), αHis103(G10), αHis89(FG1), αHis112(G19) and βHis97(FG4)] can become protonated/deuterated from the R to the T state, while two histidine residues [αHis20(B1) and βHis117(G19)] can lose a proton/deuteron. αHis103(G10), located in the α1:β1dimer interface, appears to be a Bohr group that undergoes structural changes: in the R state it is singly protonated/deuterated and hydrogen-bonded through a water network to βAsn108(G10) and in the T state it is doubly protonated/deuterated with the network uncoupled. The very long-term H/D exchange of the amide protons identifies regions that are accessible to exchange as well as regions that are impermeable to exchange. The liganded relaxed state (R state) has comparable levels of exchange (17.1% non-exchanged) compared with the deoxy tense state (T state; 11.8% non-exchanged). Interestingly, the regions of non-exchanged protons shift from the tetramer interfaces in the T-state interface (α1:β2and α2:β1) to the cores of the individual monomers and to the dimer interfaces (α1:β1and α2:β2) in the R state. The comparison of regions of stability in the two states allows a visualization of the conservation of fold energy necessary for ligand binding and release.

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ROBUST STABILITY, STABILISATION AND H-INFINITY CONTROL FOR PREMIUM-RESERVE MODELS IN A MARKOVIAN REGIME SWITCHING DISCRETE-TIME FRAMEWORK

Astin Bulletin ◽

10.1017/asb.2016.13 ◽

2016 ◽

Vol 46 (3) ◽

pp. 747-778 ◽

Cited By ~ 3

Author(s):

Lin Yang ◽

Athanasios A. Pantelous ◽

Hirbod Assa

Keyword(s):

Discrete Time ◽

Regime Switching ◽

Structural Changes ◽

Linear Matrix ◽

H Infinity Control ◽

R Process ◽

The Stability ◽

Markovian Regime Switching ◽

Markovian Regime

AbstractThe premium pricing process and the medium- and long-term stability of the reserve policy under conditions of uncertainty present very challenging issues in relation to the insurance world. Over the last two decades, applications of Markovian regime switching models to finance and macroeconomics have received strong attention from researchers, and particularly market practitioners. However, relatively little research has so far been carried out in relation to insurance. This paper attempts to consider how a linear Markovian regime switching system in discrete-time could be applied to model the medium- and long-term reserves and the premiums (abbreviated here as the P-R process) for an insurer. Some recently developed techniques from linear robust control theory are applied to explore the stability, stabilisation and robust H∞-control of a P-R system, and the potential effects of abrupt structural changes in the economic fundamentals, as well as the insurer's strategy over a finite time period. Sufficient linear matrix inequality conditions are derived for solving the proposed sub-problems. Finally, a numerical example is presented to illustrate the applicability of the theoretical results.

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