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Oikonomou P, Nikolaou C, Papachristou F, Sovatzidis A, Lambropoulou M, Giouleka C, Kontaxis V, Linardoutsos D, Papalois A, Pitiakoudis M, Tsaroucha A. Eugenol Reduced ΜPO, CD45 and HMGB1 Expression and Attenuated the Expression of Leukocyte Infiltration Markers in the Intestinal Tissue in Biliopancreatic Duct Ligation-Induced Pancreatitis in Rats. MEDICINA (KAUNAS, LITHUANIA) 2023; 60:74. [PMID: 38256335 PMCID: PMC10820626 DOI: 10.3390/medicina60010074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/30/2023] [Accepted: 12/26/2023] [Indexed: 01/24/2024]
Abstract
Background and Objectives: Inflammation and dysregulation in the intestinal barrier function in acute pancreatitis (AP) trigger pancreatic lesions, systemic inflammatory response, and multiple organ dysfunction. Eugenol, as the main component of clove (Syzygium aromaticum), is known for its antioxidant and anti-inflammatory properties. We studied the potentially beneficial effect of eugenol in a rodent model of biliopancreatic duct ligation-induced AP. Materials and Methods: Rats were randomly divided into three groups: Sham, AP, and AP + eugenol (15 mg/kg/day). Serum TNFα, IL-6, IL-18, and resistin levels, as well as IL-6, TNFα, MPO, HMGB1, and CD45 tissue expression, were determined at various timepoints after the induction of AP. Results: Eugenol attenuated hyperemia and inflammatory cell infiltration in the intestinal mucosal, submucosal, and muscular layers. IL-6 and resistin serum levels were significantly reduced in the AP + eugenol group, while serum TNFα and IL-18 levels remained unaffected overall. TNFα pancreatic and intestinal expression was attenuated by eugenol at 72 h, while IL-6 expression was affected only in the pancreas. MPO, CD45, and HMGB1 intestinal expression was significantly reduced in eugenol-treated rats. Conclusions: Eugenol managed to attenuate the inflammatory response in the intestine in duct ligation-induced AP in rats.
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Kitridis D, Savvidis P, Cheva A, Papalois A, Givissis P, Chalidis B. Are Absorbable Plates More Resistant to Infection Than Titanium Implants? An Experimental Pre-Clinical Trial in Rabbits. J Funct Biomater 2023; 14:498. [PMID: 37888163 PMCID: PMC10607271 DOI: 10.3390/jfb14100498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 09/17/2023] [Accepted: 10/07/2023] [Indexed: 10/28/2023] Open
Abstract
Background: Infection of orthopaedic implants after internal fixation of bone fractures remains a major complication with occasionally devastating consequences. Recent studies have reported that the use of absorbable materials, instead of metallic ones, may lead to a lower incidence of postoperative infection. In this experimental pre-clinical animal study, we compared the infection rate between absorbable implants consisting of copolymers composed from trimethylene carbonate, L-polylactic acid, and D, L-polylactic acid monomers, and titanium implants after the inoculation of a pathogenic microorganism. Material and Methods: We used an experimental implant-related infection model in rabbits. Sixty animals were randomly and equally divided into two groups. In all animals, the right femur was exposed via a lateral approach and a 2.5 mm two-hole titanium plate with screws (Group A), or a two-hole absorbable plate and screws (Group B), were applied in the femoral shaft. Afterwards, the implant surface was inoculated with Pseudomonas Aeruginosa at a concentration of 2 × 108 CFU/mL. The primary outcome was the comparison of the incidence of developed infection between the two groups. The wound condition was monitored on a daily basis and radiographies were obtained at 12 weeks postoperatively. Infection-related laboratory markers (white blood cell count, erythrocyte sedimentation rate, and C-reactive protein values) were assessed at 3, 6, and 16 weeks postoperatively. Histologic analysis and cultures of tissue samples were also performed to evaluate the presence of infection. Results: Clinical and laboratory signs of infection were evident in 11 rabbits in Group A (36.7%), and 4 in Group B (13.3%). The difference between the groups was statistically significant (p = 0.04). Five animals in Group B (16.7%) had clinical and histologic signs of a foreign-body reaction with significantly elevated CRP and ESR values but no simultaneous presence of infection was identified (p = 0.04). Bone remodelling with thickening of the periosteum and surrounding sclerosis was demonstrated radiologically in animals developing infection or foreign-body reactions. Conclusions: Absorbable plates and screws show lower susceptibility to infection compared to titanium ones. However, their application is associated with foreign-body reaction and the potential need for a second surgical intervention.
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Mantelou AG, Barbouti A, Goussia A, Zacharioudaki A, Papoudou-Bai A, Vlachou C, Kokkoris S, Papalois A, Galaris D, Glantzounis GK. Combined administration of membrane-permeable and impermeable iron-chelating drugs attenuates ischemia/reperfusion-induced hepatic injury. Free Radic Biol Med 2022; 193:227-237. [PMID: 36243210 DOI: 10.1016/j.freeradbiomed.2022.10.266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 10/07/2022] [Accepted: 10/07/2022] [Indexed: 12/31/2022]
Abstract
BACKGROUND The underlying pathophysiological mechanisms of hepatic ischemia-reperfusion (I/R) injury have not been completely elucidated. However, it is well known that oxidative stress, caused by a burst of reactive oxygen species (ROS) production during the reperfusion phase, plays a crucial role. A growing body of evidence indicates that the intracellular availability of free iron represents a requirement for ROS-induced adverse effects, as iron catalyzes the generation of highly reactive free radicals. The aim of this study was to examine whether a combination of iron chelators with varying lipophilicity could offer enhanced protection against I/R by diminishing the conversion of weak oxidants, like H2O2, to extremely reactive ones such as hydroxyl radicals (HO.). METHODS HepG2 cells (hepatocellular carcinoma cell line) were exposed to oxidative stress conditions after pre-treatment with the iron chelators desferrioxamine (DFO) and deferiprone (DFP) alone or in combination. Labile iron pool was estimated using the calcein-acetoxymethyl ester (calcein-AM) method and DNA damage with the comet assay. We subsequently used a rabbit model (male New Zealand white rabbits) of hepatic I/R-induced injury to investigate, by measuring biochemical (ALT, ALT, ALP, γGT) and histological parameters, whether this may be true for in vivo conditions. RESULTS The combination of a membrane-permeable iron chelator (DFP) with a strong membrane-impermeable one (DFO) raises the level of protection in both hepatic cell lines exposed to oxidative stress conditions and hepatic I/R rabbit model. CONCLUSIONS Our results show that combinations of iron chelators with selected lipophilicity and iron-binding properties may represent a valuable strategy to protect against tissue damage during reperfusion after a period of ischemia.
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Rallis KS, Wozniak A, Hui S, Stammer A, Cinar C, Sun M, Fulton-Ward T, Clarke AA, Papagrigoriadis S, Papalois A, Sideris MC. Mentoring Medical Students Towards Oncology: Results from a Pilot Multi-institutional Mentorship Programme. JOURNAL OF CANCER EDUCATION : THE OFFICIAL JOURNAL OF THE AMERICAN ASSOCIATION FOR CANCER EDUCATION 2022; 37:1053-1065. [PMID: 33242159 PMCID: PMC7688447 DOI: 10.1007/s13187-020-01919-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/01/2020] [Indexed: 06/02/2023]
Abstract
The mounting global cancer burden has generated an increasing demand for oncologists to join the workforce. Yet, students report limited oncology exposure in undergraduate medical curricula, while undergraduate oncology mentorships remain underutilised. We established an undergraduate oncology society-led mentorship programme aimed at medical students across several UK universities to increase medical student oncology exposure. We electronically recruited and paired oncologist mentors and medical student mentees and distributed a dedicated questionnaire (pre- and post-mentorship) to compare mentees' self-reported cancer specialty knowledge and oncology career motivation after undertaking a 6-week mentorship. We also determined students' interest across specialties and subspecialties and measured mentor availability via percentage programme uptake. Statistical analysis included univariate inferential tests on SPSS software. Twentynine (23.4%) of 124 oncology specialists agreed to become mentors. The mentorship was completed by 30 students across three medical schools: 16 (53.3%) Barts, 10 (33.3%) Birmingham, and 4 (13.3%) King's; 11 (36.7%) mentored by medical oncologists, 10 (33.3%) by clinical/radiation oncologists, and 9 (30%) by surgical oncologists. The mentorship generated a statically significant increase in students' knowledge of the multidisciplinary team and all oncology-related specialties including academia/research but not interest towards a career in oncology. Undergraduate oncology mentoring is an effective educational, networking and motivational tool for medical students. Student societies are a valuable asset in cultivating medical student oncology interest by connecting students to faculty and increasing mentor accessibility. Further research should focus on developing an optimal mentorship structure and evaluating long-term outcomes of such educational initiatives.
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Emin EI, Emin E, Bimpis A, Pierides M, Dedeilia A, Javed Z, Rallis KS, Saeed F, Theophilou G, Karkanevatos A, Kitapcioglu D, Aksoy ME, Papalois A, Sideris M. Teaching and Assessment of Medical Students During Complex Multifactorial Team-Based Tasks: The "Virtual on Call" Case Study. ADVANCES IN MEDICAL EDUCATION AND PRACTICE 2022; 13:457-465. [PMID: 35547870 PMCID: PMC9084906 DOI: 10.2147/amep.s357514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 03/31/2022] [Indexed: 06/15/2023]
Abstract
Abstract Although considerable efforts have been made to incorporate simulation-based learning (SBL) in undergraduate medical education, to date, most of the medical school curricula still focus on pure knowledge or individual assessment of objective structured clinical examination skills (OSCE). To this end, we designed a case study named "iG4 (integrated generation 4) virtual on-call (iVOC)". We aimed to simulate an on-call shift in a high-fidelity virtual hospital setting in order to assess delegates' team-based performance on tasks related to patient handovers (prioritisation, team allocation). Methods A total of 41 clinical year medical students were split into 3 cohorts, each of which included 3 groups of 4 or 5 people. The groups consisted of a structured mix of educational and cultural backgrounds of students to achieve homogeneity. Each performing group received the handover for 5 patients in the virtual hospital and had to identify and deal with the acutely unwell ones within 15 minutes. We used TEAMTM tool to assess team-based performances. Results The mean handover performance was 5.44/10 ± 2.24 which was the lowest across any performance marker. The overall global performance across any team was 6.64/10 ± 2.11. The first rotating team's global performance for each cycle was 6.44/10 ± 2.01, for the second 7.89/10 ± 2.09 and for the third 6.78/10 ± 1.64 (p = 0.099 between groups). Conclusion This is one of the first reported, high-fidelity, globally reproducible SBL settings to assess the capacity of students to work as part of a multinational team, highlighting several aspects that need to be addressed during undergraduate studies. Medical schools should consider similar efforts with the aim to incorporate assessment frameworks for individual performances of students as part of a team, which can be a stepping-stone for enhancing safety in clinical practice.
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Kapoulas S, Papalois A, Papadakis G, Tsoulfas G, Christoforidis E, Papaziogas B, Schizas D, Chatzimavroudis G. Safety and efficacy of absorbable and non-absorbable fixation systems for intraperitoneal mesh fixation: an experimental study in swine. Hernia 2022; 26:567-579. [PMID: 33400026 DOI: 10.1007/s10029-020-02352-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Accepted: 12/02/2020] [Indexed: 02/05/2023]
Abstract
PURPOSE Choice of the best possible fixation system in terms of safety and effectiveness for intraperitoneal mesh placement in hernia surgery remains controversial. The aim of the present study was to compare the performance of four fixation systems in a swine model of intraperitoneal mesh fixation. METHODS Fourteen Landrace swine were utilized in the study. The experiment included two stages. Initially, four pieces of mesh (Ventralight ™ ST) sizing 10 × 5 cm were placed and fixed intraperitoneally to reinforce 4 small full thickness abdominal wall defects created with diathermy. These defects were repaired primarily with absorbable suture before mesh implantation. Each mesh was anchored with a different tack device between Absorbatack™, Protack™, Capsure™, or Optifix™. The second stage took place after 60 days and included euthanasia, laparoscopy, and laparotomy via U-shaped incision to obtain the measurements for the outcome parameters. The primary endpoint of the study was to compare the peel strength of the compound tack/mesh from the abdominal wall. Secondary parameters were the extent and quality of visceral adhesions to the mesh, the degree of mesh shrinkage and the histological response around the tacks. RESULTS Thirteen out of 14 animals survived the experiment and 10 were included in the final analysis. Capsure™ tacks had higher peel strength when compared to Absorbatack™ (p = 0.028); Protack™ (p = 0.043); and Optifix™ (p = 0.009). No significant differences were noted regarding the extent of visceral adhesions (Friedman's test p value 0.854), the adhesion quality (Friedman's test p value 0.506), or the mesh shrinkage (Friedman's test p value = 0.827). Four out of the ten animals developed no adhesions at all 2 months after implantation. CONCLUSION Capsure™ fixation system provided higher peel strength that the other tested devices in our swine model of intraperitoneal mesh fixation. Our findings generate the hypothesis that this type of fixation may be superior in a clinical setting. Clinical trials with long-term follow-up are required to assess the safety and efficacy of mesh fixation systems in hernia surgery.
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Sakarellos P, Papalois A, Gakiopoulou H, Zacharioudaki I, Katsimpoulas M, Belia M, Moris D, Aggelou K, Vagios I, Davakis S, Vailas M, Liakakos T, Diamantis T, Felekouras E, Kontos M. Growth of Intestinal Neomucosa on Pedicled Gastric Wall Flap, a Novel Technique in an Animal Model. J INVEST SURG 2022; 35:1329-1339. [PMID: 35196939 DOI: 10.1080/08941939.2022.2034196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Background: Short bowel syndrome (SBS) remains an unsolved issue in modern medicine. Numerous experimental surgical techniques have been proposed in the attempt to increase the intestinal absorptive capacity.Materials and Methods: Ten female Landrace pigs, divided in two groups of 5 (A and B), were explored through a midline incision. A spindle-shaped vascularized full-thickness gastric wall flap (GWF) consisting of part of the major curvature with the gastroepiploic arch preserved was de-epithelialized and then placed as a "patch" to cover an antimesenteric border defect of either a nonfunctional blind intestinal loop (group A) or a functional intestinal loop of the gastrointestinal tract (group B). A spindle-shaped curved, rigid, low density polyethylene (LDPE) splint was sutured on the external surface of the patch in order to prevent shrinkage of GWF and collapse of the intestinal wall in group A.Results: There was a decrease of both dimensions of the patch. Microscopically a thin layer of columnar epithelial cells covered the center of the patch, evolving in shorter, blunt, poorly developed villi with increasing maturation laterally. The patch surface was covered by nearly 90%. In the three animals that died prematurely the coverage of GWF was negligent or suboptimal directly dependent on the length of survival.Conclusions: The hereby-described patching technique demonstrated the growth of intestinal neomucosa on the GWF. The capability of the stomach to provide large flaps and the advantages of the use of native tissues render this animal model valuable for the future research in the field.
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Gerogiannis I, Papalois A, Psalla D, Kambaroudis A. Beneficiary Effect of Fibrin Glue on Healing of Ileoileal Anastomoses in Rats. In Vivo 2022; 36:221-226. [PMID: 34972718 DOI: 10.21873/invivo.12694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 11/29/2021] [Accepted: 11/30/2021] [Indexed: 11/10/2022]
Abstract
BACKGROUND/AIM Intestinal anastomosis' integrity is crucial in surgery. This study aimed to investigate whether fibrin glue (FG) (a fibrin sealant containing human factor XII and fibrinogen) has a positive effect on the healing and the integrity of the ileoileal anastomosis in rats. MATERIALS AND METHODS Twenty Wistar rats underwent enterotomy, ileoileal anastomosis and divided into four groups (A: complete anastomosis-no FG, B: complete anastomosis-FG, C: incomplete anastomosis-no FG, D: incomplete anastomosis-FG). Data included leak, adhesions, bursting pressure of the anastomosis, neoangiogenesis, and hydroxyproline levels. RESULTS Angiogenesis was significantly higher in group B compared to group A (p=0.019). There were no significant differences between groups A and B regarding adhesions, hydroxyproline, and bursting pressure (p=0.500, p=0.158 and p=0.829, respectively). Hydroxyproline levels were higher in group D compared to C, but did not reach significance (p=0.098). CONCLUSION Fibrin glue has a positive effect on ileoileal anastomoses. It is not entirely clear whether this effect is due to mechanical support or to the facilitation of the healing process or both. Further research is needed before FG can be applied to humans.
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Mantelou AG, Zacharioudaki A, Pappas-Gogos G, Papalois A, Papoudou-Bai A, Goussia A, Glantzounis GK. Description of a Recovery Model in Rabbits for the Study of the Late Phase of Liver Ischemia-Reperfusion Injury. In Vivo 2022; 36:153-160. [PMID: 34972710 DOI: 10.21873/invivo.12686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 09/23/2021] [Accepted: 09/29/2021] [Indexed: 11/10/2022]
Abstract
AIM Description of an anesthetic recovery model with endotracheal intubation in rabbits which provides metabolic stability for the study of the late phase of liver ischemia/reperfusion (I/R) injury. MATERIALS AND METHODS Two groups of New Zealand rabbits, n=7 in each, were used: Ischemia/reperfusion (I/R) group (45 min of partial liver ischemia/reperfusion) and no intervention (sham) group. Blood alanine aminotransferase, lactate, pH values, mean arterial pressure and pCO2 were calculated at baseline, and at 2 and 24 h post reperfusion. Tissue samples from left (ischemic) and right (non-ischemic) liver lobes were examined at 2 and 24 h after reperfusion. RESULTS The I/R group presented significantly higher levels of alanine aminotransferase (p=0.001) at 2 and 24 h, and of lactate (p=0.016) at 2 h post reperfusion. No differences were documented for pH, mean arterial pressure and pCO2 Histological exanimation revealed significant injury at 24 h post reperfusion for the I/R group. CONCLUSION This anesthetic recovery model permitted avoidance of hypoxia and respiratory acidosis, allowing the study of the late phase of I/R injury.
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Lymperopoulos NS, Sideris M, Sofos S, Zografos C, Nanidis T, Manjumder S, Shokrollahi K, Zografos G, Papalois A. A novel plastic surgery simulation model for medical students. J Plast Reconstr Aesthet Surg 2021; 75:1261-1282. [PMID: 35034790 DOI: 10.1016/j.bjps.2021.11.072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 04/24/2021] [Accepted: 11/12/2021] [Indexed: 10/19/2022]
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Kapoulas S, Papalois A, Papadakis G, Tsoulfas G, Christoforidis E, Papaziogas B, Schizas D, Chatzimavroudis G. P049 SAFETY AND EFFICACY OF ABSORBABLE AND NON-ABSORBABLE FIXATION SYSTEMS FOR INTRAPERITONEAL MESH FIXATION: AN EXPERIMENTAL STUDY IN SWINE. Br J Surg 2021. [DOI: 10.1093/bjs/znab395.045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
Aim
Choice of the best fixation system in terms of safety and effectiveness for intraperitoneal mesh placement in hernia surgery remains controversial. The aim of this study was to compare the performance of four fixation systems in a swine model of intraperitoneal mesh fixation.
Material and Methods
Fourteen Landrace swine were utilized and the experiment included two stages. Initially, four pieces of polypropylene mesh with hydrogel barrier coating1 were fixed intraperitoneally to reinforce 4 small full thickness abdominal wall defects created with diathermy. Each mesh was anchored with a different tack device between titanium2, steel3 or absorbable (4,5) fasteners. The second stage took place after 60 days and included euthanasia, laparoscopy, and laparotomy. The primary endpoint was to compare the peel strength of the compound tack/mesh from the abdominal wall. Secondary parameters were the extent and quality of visceral adhesions to the mesh, the degree of mesh shrinkage and the histological response around the tacks.
Results
Thirteen out of 14 animals survived the experiment and 10 were included in the final analysis. Steel tacks had higher peel strength when compared to titanium and absorbable fasteners. No significant differences were noted regarding the secondary endpoints.
Conclusions
Steel fasteners provided higher peel strength that the other devices in this swine model of intraperitoneal mesh fixation. Our findings generate the hypothesis that this type of fixation may be superior in a clinical setting. Clinical trials with long-term follow-up are required to assess the safety and efficacy of mesh fixation systems in hernia surgery.
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Sideris M, Hanrahan JG, Nicolaides M, Jagiello J, Rallis KS, Emin E, Theodorou E, Mallick R, Odejinmi F, Lymperopoulos N, Papalois A, Tsoulfas G. In vivo Simulation-Based Learning for Undergraduate Medical Students: Teaching and Assessment [Response to Letter]. ADVANCES IN MEDICAL EDUCATION AND PRACTICE 2021; 12:1221-1222. [PMID: 34703352 PMCID: PMC8526365 DOI: 10.2147/amep.s342865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 10/05/2021] [Indexed: 02/05/2023]
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Douvanas A, Kalafati M, Tamvaki E, Nieri A, Papalois A, Koulouglioti C, Aggelina A, Papathanassoglou E. Ventilation With or Without Endotracheal Tube Leak in Prolonged Neonatal Asphyxia. Cureus 2021; 13:e17798. [PMID: 34660008 PMCID: PMC8496741 DOI: 10.7759/cureus.17798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2021] [Indexed: 11/05/2022] Open
Abstract
Background Severe and prolonged asphyxia can result in either intrauterine fetal death and stillbirth or multiorgan failure in surviving neonates. Establishing effective ventilation is the primary aim of resuscitation in newborns with asphyxia. The objective of this study was to compare the outcome of resuscitation by applying an endotracheal tube (ETT) with less, an ETT with moderate, and an ETT with high leakage during mechanical ventilation in swine neonates after prolonged perinatal asphyxia. Materials and methods A prospective, randomized controlled laboratory study was performed. Thirty Landrace/large white pigs, aged one to four days and weighted 1.754±218 gr, were randomly allocated into three groups depending on the ETT size: Group C (less leak: ETT no 4.0, n=10); Group A (high leak: ETT no 3.0, n=10); and Group B (moderate leak: ETT no 3.5, n=10). Mechanical asphyxia was performed until their heart rate was less than 60 bpm or their mean arterial pressure was below 15 mmHg. All animals with return of spontaneous circulation (ROSC) were monitored for four hours for their hemodynamic parameters, arterial oxygen saturation, and lactate acid levels. Results We demonstrate that 70% of the surviving animals were ventilated with an ETT with a leak (no. 3.5 and 3). A statistically significant difference was noted in PO2 (p=0.032) between Group B (126.4±53.4 mmHg) compared to Group A (72.28±29.18 mmHg) and Group C (94.28±20.46 mmHg) as well as in the right atrial pressure (p<0.001) between Group C (4.5 mmHg) vs Groups A (2 mmHg) and B (2 mmHg) during ROSC time. Lactate levels were statistically significantly lower (p=0.035) in Group C (mean=0.92 ± 0.07mmol/L) as compared to Group A (mean=1.13 ± 0.1 mmol/L) and Group B (mean= 1.08 ± 0.07 mmol /L; p = 0.034) at 4h post-ROSC. Conclusion We provide preliminary evidence that ventilation with ETT with moderate leakage improves survival after 2h of ROSC, along with oxygenation and hemodynamic parameters, in a porcine model of neonatal asphyxia and resuscitation, compared to less leakage ETT.
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Kratiras Z, Stylianaki A, Chalasti M, Iordanou C, Bouboulis G, Trigka E, Zografos G, Papalois A, Chrisofos M. Study of the effect of Sildenafil on the kidney graft quality; an experimental animal model for kidney grafts preservation before transplantation. EUR UROL SUPPL 2021. [DOI: 10.1016/s2666-1683(21)01209-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Kratiras Z, Stylianaki A, Iordanou C, Chalasti M, Bouboulis G, Trigka E, Zografos G, Papalois A, Chrisofos M. Study of the effect of Erythropoietin on the kidney graft quality; an experimental animal model for kidney grafts preservation before transplantation. EUR UROL SUPPL 2021. [DOI: 10.1016/s2666-1683(21)01210-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Sideris M, Nicolaides M, Jagiello J, Rallis KS, Emin E, Theodorou E, Hanrahan JG, Mallick R, Odejinmi F, Lymperopoulos N, Papalois A, Tsoulfas G. In vivo Simulation-Based Learning for Undergraduate Medical Students: Teaching and Assessment. ADVANCES IN MEDICAL EDUCATION AND PRACTICE 2021; 12:995-1002. [PMID: 34512069 PMCID: PMC8416184 DOI: 10.2147/amep.s272185] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 07/20/2021] [Indexed: 02/05/2023]
Abstract
An increasing emphasis on simulation has become evident in the last three decades following fundamental shifts in the medical profession. Simulation-based learning (SBL) is a wide term that encompasses several means for imitating a skill, attitude, or procedure to train personnel in a safe and adaptive environment. A classic example has been the use of live animal tissue, named in vivo SBL. We aimed to review all published evidence on in vivo SBL for undergraduate medical students; this includes both teaching concepts as well as focused assessment of students on those concepts. We performed a systematic review of published evidence on MEDLINE. We also incorporated evidence from a series of systematic reviews (eviCORE) focused on undergraduate education which have been outputs from our dedicated research network (eMERG). In vivo SBL has been shown to be valuable at undergraduate level and should be considered as a potential educational tool. Strict adherence to 3R (Reduce, Refine, Replace) principles in order to reduce animal tissue usage, should always be the basis of any curriculum. In vivo SBL could potentially grant an extra mile towards medical students' inspiration and aspiration to become safe surgeons; however, it should be optimised and supported by a well-designed curriculum which enhances learning via multi-level fidelity SBL.
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Aggelina A, Pantazopoulos I, Giokas G, Chalkias A, Mavrovounis G, Papalois A, Douvanas A, Xanthos T, Iacovidou N. Continuous chest compressions with asynchronous ventilation improve survival in a neonatal swine model of asphyxial cardiac arrest. Am J Emerg Med 2021; 48:60-66. [PMID: 33839633 DOI: 10.1016/j.ajem.2021.04.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 03/27/2021] [Accepted: 04/03/2021] [Indexed: 10/21/2022] Open
Abstract
BACKGROUND Guidelines for neonatal resuscitation recommend a 3:1 compression to ventilation ratio. However, this recommendation is based on expert opinion and consensus rather than strong scientific evidence. Our primary aim was to assess whether continuous chest compressions with asynchronous ventilations would increase return of spontaneous circulation (ROSC) rate and survival compared to the 3:1 chest compression to ventilation ratio. METHODS This was a prospective, randomized, laboratory study. Twenty male Landrace-Large White pigs, aged 1-4 days with an average weight 1.650 ± 228.3 g were asphyxiated and left untreated until heart rate was less than 60 bpm or mean arterial pressure was below 15 mmHg. Animals were then randomly assigned to receive either continuous chest compressions with asynchronous ventilations (n = 10), or standard (3:1) chest compression to ventilation ratio (n = 10). Heart rate and arterial pressure were assessed every 30 s during cardiopulmonary resuscitation (CPR) until ROSC or asystole. All animals with ROSC were monitored for 4 h. RESULTS Coronary perfusion pressure (CPP) at 30 s of CPR was significantly higher in the experimental group (45.7 ± 16.9 vs. 21.8 ± 6 mmHg, p < 0.001) and remained significantly elevated throughout the experiment. End-tidal carbon dioxide (ETCO2) was also significantly higher in the experimental group throughout the experiment (23.4 ± 5.6 vs. 14.7 ± 5.9 mmHg, p < 0.001). ROSC was observed in six (60%) animals treated with 3:1 compression to ventilation ratio and nine (90%) animals treated with continuous chest compressions and asynchronous ventilation (p = 0.30). Time to ROSC was significantly lower in the experimental group (30 (30-30) vs. 60 (60-60) sec, p = 0.021). Of note, 7 (77.8%) animals in the experimental group and 1 (16.7%) animal in the control group achieved ROSC after 30 s (0.02). At 4 h, 2 (20%) animals survived in the control group compared to 7 (70%) animals in the experimental group (p = 0.022). CONCLUSION Continuous chest compressions with asynchronous ventilations significantly improved CPP, ETCO2, time to ROSC, ROSC at 30 s and survival in a porcine model of neonatal resuscitation.
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Sideris M, Nicolaides M, Theodoulou I, Emin EI, Hanrahan JG, Dedeilia A, Theodorou E, Paparoidamis G, Abdullah Z, Papoutsos C, Pittaras T, Odejinmi F, Papalois A. Student Views on a Novel Holistic Surgical Education Curriculum (iG4): A Multi-national Survey in a Changing Landscape. In Vivo 2021; 34:1063-1069. [PMID: 32354893 DOI: 10.21873/invivo.11876] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 01/20/2020] [Accepted: 01/21/2020] [Indexed: 11/10/2022]
Abstract
AIM Essential Skills in the Management of Surgical Cases (ESMSC Marathon Course™) Integrated Generation 4 (iG4) is the first reported multifaceted undergraduate surgical course aiming to provide holistic surgical teaching. In this prospective observational study, we explored students' views on the iG4 curriculum, and identified how it can potentially address modern challenges in surgical training. MATERIAL AND METHODS Medical students were invited to apply to the course online and were screened against pre-defined criteria. A multi-national structured questionnaire incorporating five domains related to the course curriculum and our dedicated research network, was designed and distributed to participants after successful completion of the course. RESULTS Forty-one students from European and Asian medical schools completed the course and filled in the survey. The median overall evaluation score of the course was 4.73 out of 5 (interquartile range=4.21-4.72) and all students found that iG4 served the vision of holistic surgical education. ESMSC had a positive motivational effect towards following a career in surgery (p=0.012) and 92.7% of students declared that it should be an essential part of a future medical school curriculum. There was no statistically significant difference (p>0.05) in results between participants of different countries of study, year of studies or age group. CONCLUSION The ESMSC Marathon Course™ is perceived as a unique course model, with an established educational value and a positive motivational effect towards surgery. It might potentially be implemented in future medical school curricula as an essential element of undergraduate surgical education. The iG4 curriculum has opened a new exciting horizon of opportunities for advancing undergraduate holistic surgical education.
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Tsaroucha A, Kaldis V, Vailas M, Schizas D, Lambropoulou M, Papalois A, Tsigalou C, Gaitanidis A, Pitiakoudis M, Simopoulos C. The positive effect of eugenol on acute pancreatic tissue injury: a rat experimental model. Pan Afr Med J 2021; 38:132. [PMID: 33912302 PMCID: PMC8052617 DOI: 10.11604/pamj.2021.38.132.20202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 01/20/2021] [Indexed: 11/18/2022] Open
Abstract
Introduction we present a rat experimental model used to evaluate the possible reduction in the extent of pancreatic tissue injury in acute pancreatitis cases, after administration of eugenol. Methods one hundred and twenty Wistar rats were used, which were randomly assigned in 3 groups: sham (n=20), control (n=50) and eugenol (n=50). Acute pancreatitis was induced by biliopancreatic ligation in the control and eugenol groups, but not in the Sham group. In the eugenol group, eugenol was administered per-os. Five histopathological parameters, such as edema, inflammatory infiltration, duct dilatation, hemorrhage and acinar necrosis were evaluated. Results at 72 h from acute pancreatitis induction, the total histological score was diminished in the eugenol group (p<0.0005) and duct dilatation and inflammatory infiltration were reduced compared to the control group (p<0.05). In addition, at 72 h, eugenol reduced pancreatic myeloperoxidase activity (p<0.0005). Conclusion eugenol, a highly free radical scavenger agent, may have a preventive role in acute pancreatic injury, as it was evident in our rat experimental model.
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Rallis KS, Wozniak AM, Hui S, Nicolaides M, Shah N, Subba B, Papalois A, Sideris M. Inspiring the future generation of oncologists: a UK-wide study of medical students' views towards oncology. BMC MEDICAL EDUCATION 2021; 21:82. [PMID: 33530974 PMCID: PMC7852146 DOI: 10.1186/s12909-021-02506-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 01/20/2021] [Indexed: 05/18/2023]
Abstract
BACKGROUND One in 2 people born in the UK after 1960 are expected to require oncology input in their lifetime. However, only 36% of UK medical schools provide dedicated oncology placements and teaching indicating a discordance between public health impact and training. We designed a UK-wide survey to capture medical students' views on current oncology teaching and the potential role of a national undergraduate oncology symposium as an educational, networking and motivational tool. METHODS We undertook a national cross-sectional survey of UK medical students' views in oncology and satisfaction with teaching using pre-designed questionnaires. We also distributed a dedicated survey (pre and post-conference) to compare medical students' motivation towards a career in oncology after attending the national symposium. This study was prospectively approved by QMUL Ethics Committee (Reference number QMREC2348). Statistical analysis included univariate inferential tests on SPSS and GraphPad software. RESULTS The national survey was completed by 166 students representing 22 UK medical schools. Students reported limited interest, knowledge and exposure to oncology, lack of confidence in skills, and teaching dissatisfaction. Oncology was perceived as a challenging specialty (mean 4.5/5 ± 0.7), yet most students estimate receiving only 1-2 weeks of dedicated oncology teaching. The national symposium generated a statically significant increase in students' interest, knowledge, and confidence in skills surrounding oncology, improving students' perceived ability to cope with the emotional challenges in this field. CONCLUSION Students' views towards oncology alongside their teaching dissatisfaction underpin the need to revisit and strive to improve current undergraduate oncology curricula. Increasing medical student oncology exposure by proposing outcome-based guidelines and adopting a standardised undergraduate oncology curriculum should be the foremost priority in inspiring future oncologists to ensure excellent cancer patient care.
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Hanrahan JG, Sideris M, Pasha T, Dedeilia A, Papalois A, Papalois V. Postgraduate Assessment Approaches Across Surgical Specialties: A Systematic Review of the Published Evidence. ACADEMIC MEDICINE : JOURNAL OF THE ASSOCIATION OF AMERICAN MEDICAL COLLEGES 2021; 96:285-295. [PMID: 32889945 DOI: 10.1097/acm.0000000000003712] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
PURPOSE Ensuring competence for surgical trainees requires holistic assessment of the qualities and competencies necessary to practice safely and effectively. To determine the next steps toward achieving this aim, the authors conducted a systematic review to summarize and appraise the available evidence related to any assessment approach to postgraduate surgical training and to identify the dominant themes for assessment approaches across different specialties or countries. METHOD Medline and Embase were searched on January 10, 2019, without language or time restrictions. Any peer-reviewed study that described an assessment framework (in practice or novel) throughout postgraduate surgical training globally was included. An iterative review and thematic analysis were performed on full-text articles to determine assessment themes. Studies were then grouped by assessment themes. A tailored quality assessment of the studies included in the final analysis was conducted. Assessment themes and validity were compared across surgical specialties and countries. RESULTS From an initial 7,059 articles, 91 studies (evaluating 6,563 surgical trainees) were included in the final analysis. Ten defined assessment themes were extracted. Ten studies (11.0%) were deemed low risk of bias based on the quality assessment tool used and thus were determined to be high quality. Minor differences in assessment themes were observed between specialties and countries. Assessment themes neglected by individual surgical specialties and assessment themes that need validated assessment tools were identified. CONCLUSIONS This review highlights the low quality of evidence and fragmented efforts to develop and optimize surgical assessments. The minor differences observed demonstrate a common approach, globally and across specialties, related to surgical assessments. A paradigm shift in assessment approaches, which will require national and international collaboration, is required to optimize design and validation so that a comprehensive assessment of surgical competence can be implemented.
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Samiotis I, Papakonstantinou NA, Dedeilias P, Vasileiadis I, Papalois A, Deftereos S, Kotanidou A. Dantrolene Induces Mitigation of Myocardial Ischemia-Reperfusion Injury by Ryanodine Receptor Inhibition. Semin Thorac Cardiovasc Surg 2021; 34:123-132. [PMID: 33460764 DOI: 10.1053/j.semtcvs.2021.01.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 01/05/2021] [Indexed: 11/11/2022]
Abstract
The impairment of intracellular calcium homeostasis plays an essential role during ischemia-reperfusion injury. Calcium release from sarcoplasmic reticulum which is triggered by myocardial ischemia is mainly mediated by ryanodine receptors. Dantrolene sodium is a ryanodine receptor antagonist. The objective of the present study was to evaluate the in-vivo impact of dantrolene sodium on myocardial ischemia-reperfusion injury in swine models. An in vivo, experimental trial comparing 10 experimental animals which received dantrolene sodium with 9 control swine models was conducted. Their left anterior descending coronary artery was temporarily occluded for 75 minutes via a vessel tourniquet, which was then released. Myocardial reperfusion was allowed for 24 hours. Dantrolene was administered at the onset of the reperfusion period and levels of troponin, creatine phosphokinase and creatine kinase myocardial band between the two groups were compared. Additionally, various other hemodynamic parameters and left ventricular morphology and function were examined. There were significantly lower values of troponin, creatine phosphokinase and creatine kinase myocardial band in the dantrolene group indicating less ischemia-reperfusion injury. Moreover, the postischemic cardiac index was also greater in the dantrolene group, whereas viable myocardium was also better preserved. In conclusion, the in vivo cardioprotective role of dantrolene sodium against ischemia-reperfusion injury in swine models was indicated in this study. Therefore, dantrolene sodium administration could be a promising treatment against ischemia-reperfusion injury in humans. However, large randomized clinical studies should be firstly carried out to prove this hypothesis.
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Sousonis V, Sfakianaki T, Ntalianis A, Nanas I, Kontogiannis C, Aravantinos D, Kapelios C, Katsaros L, Nana M, Sampaziotis D, Sanoudou D, Papalois A, Malliaras K. Intracoronary Administration of Allogeneic Cardiosphere-Derived Cells Immediately Prior to Reperfusion in Pigs With Acute Myocardial Infarction Reduces Infarct Size and Attenuates Adverse Cardiac Remodeling. J Cardiovasc Pharmacol Ther 2021; 26:88-99. [PMID: 32677460 DOI: 10.1177/1074248420941672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Allogeneic cardiosphere-derived cells (CDCs) exert cardioprotective effects when administered intracoronarily after reperfusion in animal models of acute myocardial infarction (AMI). The "no-reflow" phenomenon develops rapidly post-reperfusion and may undermine the efficacy of cell therapy, due to poor cell delivery in areas of microvascular obstruction (MVO). We hypothesized that CDC-induced cardioprotection would be enhanced by cell administration prior to reperfusion, when microvasculature is still relatively intact, to facilitate widespread cell delivery within the ischemic area. METHODS AND RESULTS We studied 81 farm pigs; 55 completed the specified protocols. A dose-optimization study in infarcted pigs demonstrated that the doses of 5 million and 10 million CDCs are the maximum safe doses that can be administered intracoronarily at 5 minutes prior to and at 5 minutes post-reperfusion, respectively, without aggravating MVO. Quantification of acute cell retention by polymerase chain reaction demonstrated that cell delivery prior to reperfusion resulted in higher cardiac cell retention compared to delivery post-reperfusion. We then performed a randomized, placebo-controlled study to assess the long-term efficacy of intracoronary infusion of 5 million allogeneic CDCs, delivered at 5 minutes prior to reperfusion, in a porcine model of AMI. The CDC therapy resulted in decreased scar size, improved regional systolic function, and attenuation of adverse cardiac remodeling (manifested as preserved global systolic function, preserved end-systolic volume, and decreased interstitial fibrosis) compared to placebo at 30 days post-MI. CONCLUSIONS Dose-optimized intracoronary infusion of allogeneic CDCs prior to reperfusion in a porcine model of AMI is feasible, safe and confers long-term benefits.
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Sideris M, Papalois V, Athanasiou T, Papagrigoriadis S, Pierides M, Velmahos G, Papalois A. A Novel Multi-faceted Course Blueprint to Support Outcome-based Holistic Surgical Education: The Integrated Generation 4 Model (iG4). In Vivo 2020; 34:503-509. [PMID: 32111747 DOI: 10.21873/invivo.11801] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 12/04/2019] [Accepted: 12/06/2019] [Indexed: 11/10/2022]
Abstract
BACKGROUND/AIM We present a novel multi-faceted, internationally adaptable course curriculum blueprint, which provides holistic surgical education at the undergraduate level. MATERIALS AND METHODS The Integrated Generation 4 (iG4) course (Essential Skills in the Management of Surgical Cases - ESMSC Marathon course) curriculum consists of four essential learning components: core skills-based learning, case-based discussions, basic science workshops and soft-skills. These are all clustered in a specialty-led network architecture. Every cluster consists of modules from the four learning cores, while network nodes are modules that are mutually shared by more than one clusters. RESULTS We produced a standardized blueprint of 50 modules based on the 4 learning cores, covering 9 surgical specialties. This resulted in a curriculum map where every module is described using 3 parameters: χ axis (skills component), y axis (knowledge component), z axis (specialty component). CONCLUSION iG4 proof of concept sets the ground for a novel, reproducible and standardised effort to produce a portfolio of undergraduate surgical skills serving the vision of holistic surgical education.
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Kormpakis I, Papalois A, Kinnas P, Zoubos AB, Sioutis I, Dimitriadi A, Soucacos PN, Johnson EO. Silicone tubes with thyroid hormone (Τ3) and BDNF as an alternative to autografts for bridging neural defects. Injury 2020; 51:2879-2886. [PMID: 32284185 DOI: 10.1016/j.injury.2020.03.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 02/24/2020] [Accepted: 03/07/2020] [Indexed: 02/02/2023]
Abstract
The way thyroid hormone works in peripheral nerve regeneration has not been fully elucidated, although studies have shown that it has a strong positive effect on nerve regeneration. It is argued that its action is probably stronger than the neurotrophic factors that have been used for some time. It is hypothesized that the use of thyroid hormone in the nerve tubes has a beneficial effect on nerve regeneration to the extent that the results of its use are comparable to those of the autograft technique in bridging small nerve deficits. In this experimental study, we examined the effect of thyroid hormone and BDNF (Brain Derived Neurotrophic Factor) on the repair of 10 mm nerve defects when administered within silicone nerve tubes and compared the results with the autograft method. Thyroid hormone promotes nerve regeneration mainly by increasing its speed and its effect on the maturation of nerve fibers compared to the other groups where the nerve deficit was bridged by entubulation. Also, better organization and the absence of intraneural fibrosis, compared to the other groups, may argue for the action of thyroid hormone in regulating the inflammatory response. Functionally, the AG group showed better results compared to the other groups by the end of the study (16 weeks).
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