POLYMORPHISM OF THE THYMIC CORPUSCLES IN CASE OF EXPERIMENTAL BURN DI- SEASE AND THE INFUSION OF COMBINED HYPEROSMOLAR SOLUTIONS

2011 ◽  
Vol 10 (4) ◽  
pp. 36-39
Author(s):  
E. V. Cherkasov
2019 ◽  
Vol 25 (2) ◽  
pp. 56-63
Author(s):  
V.G. Cherkasov ◽  
R.M. Matkivska ◽  
E.V. Cherkasov ◽  
R.F. Kaminskyi ◽  
L.M. Yaremenko

The pathogenesis of burn immune dysfunction and burn enteropathy needs further clarification given that the cellular lesions of lymphoid tissue associated with mucous membranes are the least studied. The purpose of the study was to establish reactive and destructive changes in Peyer’s patches of rats after burn injury of the skin with the use of intravenous infusion of isotonic sodium chloride solution and combined colloid-hyperosmolar solutions. White male rats weighing 160-200 g at 6 months of age were divided into 4 groups (18 animals in each group): I, II, III – rats with burn skin injury (grade II-III burn with an area of 23% of body surface area and the development of moderate-severity shock state) which was administered a separate intravenous infusion once a day for the first 7 days of the experiment with isotonic sodium chloride, lactoprotein with sorbitol and HAES-LX-5%, in each case at a dose of 10 ml/kg; IV – intact animals. The material was collected from rats under deep thiopental intraperitoneal anesthesia after 1, 3, 7, 14, 21 and 30 days after burn injury. Biopsies from Peyer’s patches for histological and electron microscopic examination were processed using conventional methods. Investigation of histological preparations stained with hematoxylin-eosin was performed on an Olympus BX51 microscope. Ultrathin sections were contrasted on copper support meshes with uranyl acetate and lead citrate according to Reynolds and studied using a PEM-125K electron microscope. Electron and light microscopy data indicate that intravenous infusion of colloidal-hyperosmolar solutions (lactoprotein with sorbitol and HAES-LX-5%) promotes suppression of inflammatory response, inhibits necrosis, and optimizes lymphoid apoptosis at Peyer’s patches of rats with experimental burn disease caused by burn injury to the skin of 21-23% of the body surface. Apoptotic lymphocytes and their apoptotic bodies are effectively phagocytosed by macrophages and are digestible in heterophagolysosomes. The apoptotic altered dendritic cells in Peyer’s patches are characterized by osmiophilic cytoplasm and a nucleus with high electron density amorphous nucleoplasm. In the cytoplasm are located mitochondria with enlightened matrix and destroyed cristae, irregularly expanded tubules of variable configuration of a granular endoplasmic reticulum with electronically transparent content and numerous derivatives of their vacuole transformation, which are sharply darkened. The fusion of vacuoles leads to the formation of large electron-luminous cavities filled with various residues of compacted degraded cellular structures. Vacualization promotes site segmentation of condensed cytoplasm of apoptotic dendritic cells and formation of apoptotic blebs, which are subject to entrapment and subsequent sequential degradation with the participation of neighboring macrophages. The structural changes of the organelles of the protein-synthesizing apparatus found in Peyer’s plaque cells in rats with experimental burn disease can be regarded as a manifestation caused by functional overload of the granular endoplasmic reticulum (ER-stress). The consequence of optimal development of ER-stress and subsequent unfolded protein response is the apoptotic degradation of the corresponding cell, the course of which is modified by the use of colloid-hyperosmolar solutions.


Neonatology ◽  
2021 ◽  
pp. 1-7
Author(s):  
Faiza Latheef ◽  
Hanna Wahlgren ◽  
Helene Engstrand Lilja ◽  
Barbro Diderholm ◽  
Mattias Paulsson

<b><i>Introduction:</i></b> Necrotizing enterocolitis (NEC) is a disease predominantly affecting preterm infants. The administration of hyperosmolar solutions could lead to the development of NEC. The objective of this study was to measure the osmolality of enteral medications used in clinical practice and to assess the risk of NEC following exposure to hyperosmolar medications. <b><i>Methods:</i></b> A retrospective cohort study in extremely preterm infants (gestational age &#x3c;28 weeks) born between 2010 and 2016 at a tertiary neonatal intensive care unit in Sweden. 465 infants were identified via the Swedish Neonatal Quality register. Data relating to enteral administrations received during a two-week period were collected from the medical records. The osmolalities of medications were measured using an osmometer. Logistic regression was used to calculate the odds ratio of developing NEC. <b><i>Results:</i></b> A total of 253 patients met the inclusion criteria. The osmolalities of 5 commonly used medications significantly exceeded the recommended limit of 450 mOsm/kg set by the American Academy of Paediatrics (AAP). Most patients (94%) received at least one hyperosmolar medication. No significant risk of developing NEC could be found. <b><i>Conclusion:</i></b> The medications used in clinical practice can significantly exceed the limit set by the AAP. This study does not indicate an increased risk of developing NEC in extremely preterm infants following exposure to hyperosmolar medications. Further studies in larger cohorts are needed to determine the specific cut-off level of osmolality in relation to the pathogenesis of NEC.


2008 ◽  
Vol 295 (5) ◽  
pp. F1336-F1341 ◽  
Author(s):  
Nathan W. Blessing ◽  
Mitsi A. Blount ◽  
Jeff M. Sands ◽  
Christopher F. Martin ◽  
Janet D. Klein

The UT-A1 and UT-A3 urea transporters are expressed in the terminal inner medullary collecting duct (IMCD) and play an important role in the production of concentrated urine. We showed that both hyperosmolarity and vasopressin increase urea permeability in perfused rat terminal IMCDs and that UT-A1 and UT-A3 accumulate in the plasma membrane in response to vasopressin. In this study, we investigated whether hyperosmolarity causes UT-A1 and/or UT-A3 to accumulate in the plasma membrane or represents a complimentary stimulatory pathway. Rat IMCD suspensions were incubated in 450 vs. 900 mosM solutions. We biotinylated the IMCD surface proteins, collected, and analyzed them. Membrane accumulation was assessed by Western blotting of the biotinylated protein pool probed with anti-UT-A1 or anti-UT-A3. We studied the effect of NaCl, urea, and sucrose as osmotic agents. Membrane-associated UT-A1 and UT-A3 increased relative to control levels when either NaCl (UT-A1 increased 37 ± 6%; UT-A3 increased 46 ± 13%) or sucrose (UT-A1 increased 81 ± 13%; UT-A3 increased 60 ± 8%) was used to increase osmolarity. There was no increase in membrane UT-A1 or UT-A3 when urea was added. Analogously, UT-A1 phosphorylation was increased in NaCl- and sucrose- but not in urea-based hyperosmolar solutions. Hypertonicity also increased UT-A3 phosphorylation. We conclude that the increase in the urea permeability in response to hyperosmolarity reflects both UT-A1 and UT-A3 movement to the plasma membrane and may be a direct response to tonicity. Furthermore, this movement is accompanied by, and may require, increased phosphorylation in response to hypertonicity.


1993 ◽  
Vol 265 (5) ◽  
pp. C1201-C1210 ◽  
Author(s):  
D. W. Whalley ◽  
L. C. Hool ◽  
R. E. Ten Eick ◽  
H. H. Rasmussen

The effect on the sarcolemmal Na(+)-K+ pump of exposure to anisosmolar solutions was examined using whole cell patch clamping and ion-selective microelectrodes. Na(+)-K+ pump currents were measured in single ventricular myocytes by using pipette Na+ concentrations ([Na]pip) of 0-70 mM. The relationship between [Na]pip and pump current was well described by the Hill equation. The [Na]pip for half-maximal pump current (K0.5) was 21.4 mM in isosmolar (310 mosM) solution. K0.5 was 12.8 mM during cell swelling in hyposmolar solution (240 mosM) and 39.0 mM during cell shrinkage in hyperosmolar solution (464 mosM). The maximal pump currents, derived from the best fit of the Hill equation, and the Hill coefficients were similar in isosmolar, hyposmolar, and hyperosmolar solutions. A sustained (> 20 min) decrease in the intracellular Na+ activity developed during exposure of intact papillary muscles to hyposmolar solutions, and a sustained increase developed during exposure to hyperosmolar solutions. We conclude that osmotic myocyte swelling stimulates the sarcolemmal Na(+)-K+ pump at near-physiological levels of intracellular Na+, whereas shrinkage inhibits the pump. These changes are due to increases and decreases, respectively, in the apparent affinity of the pump for Na+.


Author(s):  
Stefan Morarasu ◽  
Bianca-Codrina Morarasu ◽  
Nicolae Ghețu ◽  
Mihail-Gabriel Dimofte ◽  
Radu Iliescu ◽  
...  

Abstract AIM Despite a wide variety of models found in literature, choosing the right one can be difficult as many of them are lacking precise methodology. This study aims to analyze and compare original burn models in terms of burn device and technique, parameters, and wound depth assessment. METHODS A systematic search was performed according to PRISMA guidelines on studies describing original experimental burn models in rats. The adapted PICO formula and ARRIVE checklist were followed for inclusion and assessment of quality of studies. Characteristics of animals, burn technique, burn parameters and method of histological confirmation of burn depth were recorded. RESULTS Twenty-seven studies were included in the final analysis. Most studies used direct contact with skin for burn infliction (n=20). The rat’s dorsum was the most common site (n=18). Ten studies used manually controlled burn devices, while ten designed automatic burn devices with control over temperature (n=10), exposure time (n=5), and pressure (n=5). Most studies (n=7) used a single biopsy taken from the center of the wound to confirm burn depth immediately after burn infliction. CONCLUSION From the wide variety of burn models in current literature, our study provides an overview of the most relevant experimental burn models in rats aiding researchers to understand what needs to be addressed when designing their burn protocol. Models cannot be compared as burn parameters variate significantly. Assessment of burn depth should be done in a standardized, sequential fashion in future burn studies to increase reproducibility.


2006 ◽  
Vol 11 (3) ◽  
pp. 154-156
Author(s):  
Vera Deacon ◽  
Susan Oliver

Abstract Peripherally inserted central catheters (PICCs) are used in many different patient populations. The indications for use vary and include infusions of hyperalimentation, chemotherapeutic agents, hyperosmolar solutions, antibiotics, or long-term rehydration. However, on occasion, there are clients who do not fit the typical criteria for PICC insertion. This includes, but is not limited to, those individuals who are receiving frequent intravenous (IV) “sticks” or even short-term infusions of irritating drugs. The behavioral health client is one who may not be the typical PICC or IV patient but who may benefit from the placement of a PICC for certain treatment modalities.


Author(s):  
I.G. Horak ◽  
G.J. Gallivan ◽  
A.M. Spickett ◽  
A.L.F. Potgieter

Sixteen experimental burn plot replicates, in groups of four, in four landscape zones of the Kruger National Park, South Africa, and from which wildlife are not excluded, have been subjected to fixed, regular burning regimens since 1954. In 1999, a study to determine the effect of burning on ixodid ticks questing for hosts from the vegetation of the plots was initiated, and six sub-plots, with identical histories, within each of two of the burn plot replicates in Combretum collinum / Combretum zeyheyri woodland on granite, were selected. With few exceptions these 12 sub-plots, as well as unburned vegetation adjacent to each of the replicates, were sampled for ticks at monthly intervals for a period of 39 months by dragging with flannel strips. The existing regimen of burning during August or during October on individual sub-plots was continued during this time. A total of 14 tick species was recovered from the plots of which nine could be considered major species. Sufficient numbers for statistical analysis of only eight species were, however, collected. Burning appeared to have little short-term effect on the number of ticks recovered. In the longer term, the response varied from no change, an increase, or a decrease in the numbers of ticks collected each year after burning. Tick species, life cycle, seasonality, questing strategy, host preference and host utilization of the habitat were important determinants of the effect of burning.


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