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- Oltean, Mihai, 1976, et al.
(author)
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A sequential assessment of the preservation injury in porcine intestines
- 2017
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In: Journal of Surgical Research. - : Elsevier BV. - 0022-4804. ; 216, s. 149-157
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Journal article (peer-reviewed)abstract
- Background: Clinical and experimental evidence strongly suggest that ischemia-reperfusion injury after intestinal transplantation has deleterious short-and long-term effects and finding means to reduce ischemia-reperfusion injury is a major research area. The anatomical and physiological similarities between the human and porcine digestive tract favor its use as a preclinical model for translational research. Intriguingly, no systematic appraisal of the development of the intestinal preservation injury in pigs is available. Materials and methods: Intestinal procurement was performed in nine pigs using histidine-tryptophan-ketoglutarate solution as preservation fluid. Ileal biopsies were obtained after 8, 14, and 24 h of static cold storage (SCS), and the preservation injury was assessed morphologically (Chiu score) as well as on the molecular level. Tight junction (zonula occludens, claudin-3 and 4, tricellulin, and occludin) and adherens junctions (E-cadherin) proteins were studied using immunofluorescence and Western blot. Results: Eight hours of SCS induced minimal mucosal changes (Chiu grade 1) that advanced to significant subepithelial edema (Chiu grade 3) after 24 h; progressive Goblet cell depletion was also noted. Apoptosis (studied by cleaved caspase-3 staining significantly increased after 24 h of SCS. Significant molecular changes with decreasing expression of zonula occludens, tricellulin, and occludin were evident already after 8 h of SCS and continuously worsened. Claudin-3 and Claudin-4 and E-cadherin expression remained relatively unaltered during SCS. Conclusions: Important molecular alterations precede histologic changes during SCS of the porcine intestine and may be used as more sensitive injury markers than histologic changes in intestinal ischemia and transplantation. (C) 2017 Elsevier Inc. All rights reserved.
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| 2. |
- Oltean, Mihai, 1976, et al.
(author)
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Optimal Solution Volume for Luminal Preservation: A Preclinical Study in Porcine Intestinal Preservation
- 2016
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In: Transplantation Proceedings. - : Elsevier BV. - 0041-1345. ; 48:2, s. 532-535
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Journal article (peer-reviewed)abstract
- Background. Rodent studies suggest that luminal solutions alleviate the mucosal injury and prolong intestinal preservation but concerns exist that excessive volumes of luminal fluid may promote tissue edema. Differences in size, structure, and metabolism between rats and humans require studies in large animals before clinical use. Methods. Intestinal procurement was performed in 7 pigs. After perfusion with histidine-tryptophan-ketoglutarate (HTK), 40-cm-long segments were cut and filled with 13.5% polyethylene glycol (PEG) 3350 solution as follows: VO (controls, none), V1 (0.5 mL/cm), V2 (1 mL/cm), V3 (1.5 mL/cm), and V4 (2 mL/cm). Tissue and luminal solutions were sampled after 8, 14, and 24 hours of cold storage (CS). Preservation injury (Chiu score), the apical membrane (Z0-1, brush-border maltase activity), and the electrolyte content in the luminal solution were studied. Results. In control intestines, 8-hour CS in HTK solution resulted in minimal mucosal changes (grade 1) that progressed to significant subepithelial edema (grade 3) by 24 hours. During this time, a gradual loss in ZO-1 was recorded, whereas maltase activity remained unaltered. Moreover, variable degrees of submucosal edema were observed. Luminal introduction of high volumes (2 mUmL) of PEG solution accelerated the development of the subepithelial edema and submucosal edema, leading to worse histology. However, ZO-1 was preserved better over time than in control intestines (no luminal solution). Maltase activity was reduced in intestines receiving luminal preservation. Luminal sodium content decreased in time and did not differ between groups. Conclusions. This PEG solution protects the apical membrane and the tight-junction proteins but may favor water absorption and tissue (submucosal) edema, and luminal volumes >2 mL/cm may result in worse intestinal morphology.
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| 3. |
- Söfteland, John M., 1977, et al.
(author)
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Intestinal Preservation Injury: A Comparison Between Rat, Porcine and Human Intestines.
- 2019
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In: International journal of molecular sciences. - : MDPI AG. - 1422-0067. ; 20:13
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Journal article (peer-reviewed)abstract
- Advanced preservation injury (PI) after intestinal transplantation has deleterious short- and long-term effects and constitutes a major research topic. Logistics and costs favor rodent studies, whereas clinical translation mandates studies in larger animals or using human material. Despite diverging reports, no direct comparison between the development of intestinal PI in rats, pigs, and humans is available. We compared the development of PI in rat, porcine, and human intestines. Intestinal procurement and cold storage (CS) using histidine-tryptophan-ketoglutarate solution was performed in rats, pigs, and humans. Tissue samples were obtained after 8, 14, and 24 h of CS), and PI was assessed morphologically and at the molecular level (cleaved caspase-3, zonula occludens, claudin-3 and 4, tricellulin, occludin, cytokeratin-8) using immunohistochemistry and Western blot. Intestinal PI developed slower in pigs compared to rats and humans. Tissue injury and apoptosis were significantly higher in rats. Tight junction proteins showed quantitative and qualitative changes differing between species. Significant interspecies differences exist between rats, pigs, and humans regarding intestinal PI progression at tissue and molecular levels. These differences should be taken into account both with regards to study design and the interpretation of findings when relating them to the clinical setting.
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| 4. |
- Tolba, R. H., et al.
(author)
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Defining Standards in Experimental Microsurgical Training: Recommendations of the European Society for Surgical Research (ESSR) and the International Society for Experimental Microsurgery (ISEM)
- 2017
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In: European Surgical Research. - : S. Karger AG. - 0014-312X .- 1421-9921. ; 58:5-6, s. 246-262
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Journal article (peer-reviewed)abstract
- Background: Expectations towards surgeons in modern surgical practice are extremely high with minimal complication rates and maximal patient safety as paramount objectives. Both of these aims are highly dependent on individual technical skills that require sustained, focused, and efficient training outside the clinical environment. At the same time, there is an increasing moral and ethical pressure to reduce the use of animals in research and training, which has fundamentally changed the practice of microsurgical training and research. Various animal models were introduced and widely used during the mid-20th century, the pioneering era of experimental microsurgery. Since then, high numbers of ex vivo training concepts and quality control measures have been proposed, all aiming to reduce the number of animals without compromising quality and outcome of training. Summary: Numerous microsurgical training courses are available worldwide, but there is no general agreement concerning the standardization of microsurgical training. The major aim of this literature review and recommendation is to give an overview of various aspects of microsurgical training. We introduce here the findings of a previous survey-based analysis of microsurgical courses within our network. Basic principles behind microsurgical training (3Rs, good laboratory practice, 3Cs), considerations around various microsurgical training models, as well as several skill assessment tools are discussed. Recommendations are formulated following intense discussions within the European Society for Surgical Research (ESSR) and the International Society for Experimental Microsurgery (ISEM), based on scientific literature as well as on several decades of experience in the field of experimental (micro) surgery and preclinical research, represented by the contributing authors. Key Messages: Although ex vivo models are crucial for the replacement and reduction of live animal use, living animals are still indispensable at every level of training which aims at more than just a basic introduction to microsurgical techniques. Modern, competency-based microsurgical training is multi-level, implementing different objective assessment tools as outcome measures. A clear consensus on fundamental principles of microsurgical training and more active international collaboration for the sake of standardization are urgently needed. (C) 2017 S. Karger AG, Basel
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| 5. |
- Bresler, Ayko, et al.
(author)
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A Grading Score for Colon Preservation Injury in the Rat
- 2016
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In: Transplantation Proceedings. - : Elsevier BV. - 0041-1345. ; 48:2, s. 521-524
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Journal article (peer-reviewed)abstract
- Background. Colon transplantation is rarely performed because of the fear for an advanced ischemic injury that may favor septic complications. Systematic studies on colon preservation are missing. The score used to evaluate the preservation injury of the colon is adapted from that used for the small intestine, despite histological and biological differences between the two organs. We studied sequentially the tissue changes in the rat colon during prolonged cold storage (CS) in histidine-tryptophan-ketoglutarate (HTK) solution and designed a grading score specific for the colon. Methods. Large bowels of Sprague-Dawley rats (n = 9) were perfused in situ with HTK and stored at 4 degrees C for 6 hours, 12 hours, 18 hours, and 24 hours. Samples from the proximal colon were stained with hematoxylin-eosin and alcian blue. Tight junction protein zonulla occludens (ZO)-1 was also studied. Results. Minimal subepithelial edema (hallmark of small intestinal preservation injury) was observed throughout the 24 hours of CS. The two major changes observed during the colonic CS were progressive submucosal edema and the depletion of Goblet cells (GC). The submucosal edema was absent at 6 hours, started after 12 hours, and become significant (over 50% of the circumference) after 18 hours of CS. Depletion of GC started in the luminal half of the crypts between 12 and 18 hours of CS, and all samples revealed significant GC depletion only after 24 hours. The overall appearance of the mucosa was little affected under the CS, and ZO-1 expression was frequently maintained throughout the first 18 hours. Conclusions. The colon is more resilient to cold ischemia than the small bowel and maintains its histological epithelial features longer than the small intestine. On the basis of these serial observations, we suggest the following grading score: grade 0: normal mucosa, repleted GC, mucosa adhering to the muscular layer; grade 1: limited submucosal edema, repleted GC; grade 2: limited submucosal edema, GC depletion in the luminal half of the crypts; grade 3: advanced (>50% of circumference) submucosal edema, GC depletion in the luminal half of the crypts; grade 4: advanced mucosal injury (edema, GC depletion, epithelial breakdown).
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| 6. |
- Romosan, Gina, et al.
(author)
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Meningitis sepsis after IUD insertion, a case presentation.
- 2013
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In: Revista Medico-Chirurgicala A Societat II de Medici Si Naturalisti Din Iasi. - 0048-7848. ; 117:4, s. 929-933
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Journal article (peer-reviewed)abstract
- Neisseria meningitidis is a normal commensal of human mucous membranes that is no longer considered to be restricted to the nasopharynx. Due to the practice of oral sex, the mucous membranes of the cervix, urethra or anus have become a potential infection site for this bacterium. Inserting an intrauterine device (IUD), can alter the protective barrier of the endocervical mucosa, allowing for bacterial infection and systemic spread. We present a case report of a 40-year-old woman who presented with abdominal pain, spotting and fever after inserting an IUD and developed a fulminant septical shock. Blood cultures and cultures from ascites showed the presence of Neisseria meningitidis group Y. From our knowledge, there are a few cases presented in the literature of toxic shock syndrome after IUD insertion, caused by Staphylococcus aureus or Streptococcus group A, but this is the first case of meningococcal sepsis after IUD insertion described. So, even though IUDs rarely cause significant infection, physicians should consider this device as a possible source in reproductive-aged women with the clinical features of sepsis.
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