Emergency surgical obstetrics simulation training: an ex vivo low-cost model using bovine uterus and porcine bladder for haemostatic uterine brace suture techniques

2020 ◽  
Vol 7 (1) ◽  
pp. 26-30 ◽  
Author(s):  
Amy Sinclair ◽  
Mohamed Sayed Allam ◽  
Evelyn Jean Ferguson ◽  
Mohamed Khairy Mehasseb

Postpartum haemorrhage remains a leading cause of maternal mortality and morbidity. While conventional obstetrics training curricula describe at length the management of postpartum haemorrhage, obstetrics trainees rarely have exposure to surgical management of postpartum haemorrhage in emergency situations due to reduced hours of training. Procedures such as the transverse or longitudinal haemostatic uterine brace sutures are recognised to be safe, simple and allow for the preservation of the uterus. Training during emergency situations is rarely practical or ideal. We describe a simple model that simulates the atonic postnatal uterus and allows trainees to practise the safe placement of the brace sutures. We use a bovine uterus model with attached broad ligament, bladder and ureters for the transverse haemostatic suture. For the longitudinal brace suture, we use a porcine bladder to simulate the uterus, with the ureters and bladder mesentery simulating the tubes and broad ligaments. The placement of the sutures can be practised with the uterus/bladder closed, or open akin to a caesarean section. Tissue dissection and feedback is almost similar to in vivo conditions. The sutures are inserted and driven using the material and correct placement used during real surgery. Our wet lab training model allows the acquisition, maintenance and enhancement of the required technical skills in a controlled environment, using inexpensive, reproducible and widely available specimens. The model has proved successful in both high and low-resource healthcare settings.

Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4591 ◽  
Author(s):  
Pablo Blázquez-Carmona ◽  
Manuel Sanchez-Raya ◽  
Juan Mora-Macías ◽  
Juan Antonio Gómez-Galán ◽  
Jaime Domínguez ◽  
...  

For the monitoring of bone regeneration processes, the instrumentation of the fixation is an increasingly common technique to indirectly measure the evolution of bone formation instead of ex vivo measurements or traditional in vivo techniques, such as X-ray or visual review. A versatile instrumented external fixator capable of adapting to multiple bone regeneration processes was designed, as well as a wireless acquisition system for the data collection. The design and implementation of the overall architecture of such a system is described in this work, including the hardware, firmware, and mechanical components. The measurements are conditioned and subsequently sent to a PC via wireless communication to be in vivo displayed and analyzed using a developed real-time monitoring application. Moreover, a model for the in vivo estimation of the bone callus stiffness from collected data was defined. This model was validated in vitro using elastic springs, reporting promising results with respect to previous equipment, with average errors and uncertainties below 6.7% and 14.04%. The devices were also validated in vivo performing a bone lengthening treatment on a sheep metatarsus. The resulting system allowed the in vivo mechanical characterization of the bone callus during experimentation, providing a low-cost, simple, and highly reliable solution.


2015 ◽  
Vol 29 (4) ◽  
pp. 493-502 ◽  
Author(s):  
Dan Martin ◽  
Mircea Radu Gorgan

Abstract Introduction: Microsurgery training is a key step for the young neurosurgeons. Both in vascular and peripheral nerve pathology, microsurgical techniques are useful tools for the proper treatment. Many training models have been described, including ex vivo (chicken wings) and in vivo (rat, rabbit) ones. Complex microsurgery training include termino-terminal vessel anastomosis and nerve repair. The aim of this study was to describe a reproducible complex microsurgery training model in rats. Materials and methods: The experimental animals were Brown Norway male rats between 10-16 weeks (average 13) and weighing between 250-400g (average 320g). We performed n=10 rat hind limb replantations. The surgical steps and preoperative management are carefully described. We evaluated the vascular patency by clinical assessment-color, temperature, capillary refill. The rats were daily inspected for any signs of infections. The nerve regeneration was assessed by foot print method. Results: There were no case of vascular compromise or autophagia. All rats had long term survival (>90 days). The nerve regeneration was clinically completed at 6 months postoperative. The mean operative time was 183 minutes, and ischemia time was 25 minutes.


2021 ◽  
Author(s):  
Kimberly Kroupa ◽  
Man I Wu ◽  
Juncheng Zhang ◽  
Magnus Jensen ◽  
Wei Wong ◽  
...  

The development of treatments for osteoarthritis (OA) is burdened by the lack of standardized biomarkers of cartilage health that can be applied in clinical trials. We present a novel arthroscopic Raman probe that can optically biopsy cartilage and quantify key ECM biomarkers for determining cartilage composition, structure, and material properties in health and disease. Technological and analytical innovations to optimize Raman analysis include: 1) multivariate decomposition of cartilage Raman spectra into ECM-constituent-specific biomarkers (glycosaminoglycan [GAG], collagen [COL], water [H2O] scores), and 2) multiplexed polarized Raman spectroscopy to quantify superficial zone collagen anisotropy via a PLS-DA-derived Raman collagen alignment factor (RCAF). Raman measurements were performed on a series of ex vivo cartilage models: 1) chemically GAG-depleted bovine cartilage explants (n=40), 2) mechanically abraded bovine cartilage explants (n=30), 3) aging human cartilage explants (n=14), and 4) anatomical-site-varied ovine osteochondral explants (n=6). Derived Raman GAG score biomarkers predicted 95%, 66%, and 96% of the variation in GAG content of GAG-depleted bovine explants, human explants, and ovine explants, respectively (p<0.001). RCAF values were significantly different for explants with abrasion-induced superficial zone collagen loss (p<0.001). The multivariate linear regression of Raman-derived ECM biomarkers (GAG and H2O scores) predicted 94% of the variation in elastic modulus of ovine explants (p<0.001). Finally, we demonstrated the first in vivo Raman arthroscopy assessment of an ovine femoral condyle through intraarticular entry into the synovial capsule. This work advances Raman arthroscopy towards a transformative low cost, minimally invasive diagnostic platform for objective monitoring of treatment outcomes from emerging OA therapies.


2020 ◽  
Author(s):  
Erika Chelales ◽  
Robert Morhard ◽  
Corrine Nief ◽  
Brian Crouch ◽  
Alan Sag ◽  
...  

Abstract PurposeEthanol provides a rapid, low-cost ablative solution for liver tumors with a small technological footprint but suffers from uncontrolled diffusion in target tissue, limiting treatment precision and accuracy. The authors demonstrate that incorporating the gel-forming polymer ethyl cellulose to ethanol localizes the distribution. This therapy may have a low barrier of entry for cancer care in low- and middle- income countries.Materials and MethodsThe relationship of radiodensity to ethanol concentration was characterized with water-ethanol surrogates. Ex vivo EC-ethanol ablations were performed to optimize the formulation (n=6). In vivo ablations were performed to compare the optimal EC-ethanol formulation to pure ethanol (n=6). Ablations were monitored with CT and ethanol distribution volume was quantified. Livers were explanted, sectioned and stained with NADH-diaphorase to determine the ablative extent.ResultsCT imaging of ethanol-water surrogates demonstrated the ethanol concentration-radiodensity relationship is approximately linear. A concentration of 12% EC in ethanol created the largest distribution volume, more than 8-fold that of pure ethanol, ex vivo. In vivo, 12% EC-ethanol was superior to pure ethanol, yielding a distribution volume 3 times greater and an ablation zone 6 times greater than pure ethanol.Conclusions EC-ethanol, a novel gel formulation injectable ablative injectate, safely increases distribution and necrosis compared to pure ethanol.


2019 ◽  
Vol 10 (10) ◽  
Author(s):  
Juanjuan Xiao ◽  
Fei Wang ◽  
Hui Lu ◽  
Sanpeng Xu ◽  
Ling Zou ◽  
...  

Abstract MET overactivation is one of the crucial reasons for tyrosine kinase inhibitor (TKI) resistance, but the mechanisms are not wholly clear. Here, COX2, TOPK, and MET expression were examined in EGFR-activating mutated NSCLC by immunohistochemical (IHC) analysis. The relationship between COX2, TOPK, and MET was explored in vitro and ex vivo. In addition, the inhibition of HCC827GR cell growth by combining COX2 inhibitor (celecoxib), TOPK inhibitor (pantoprazole), and gefitinib was verified ex vivo and in vivo. We found that COX2 and TOPK were highly expressed in EGFR-activating mutated NSCLC and the progression-free survival (PFS) of triple-positive (COX2, MET, and TOPK) patients was shorter than that of triple-negative patients. Then, we observed that the COX2-TXA2 signaling pathway modulated MET through AP-1, resulting in an inhibition of apoptosis in gefitinib-resistant cells. Moreover, we demonstrated that MET could phosphorylate TOPK at Tyr74 and then prevent apoptosis in gefitinib-resistant cells. In line with these findings, the combination of celecoxib, pantoprazole, and gefitinib could induce apoptosis in gefitinib-resistant cells and inhibit tumor growth ex vivo and in vivo. Our work reveals a novel COX2/MET/TOPK signaling axis that can prevent apoptosis in gefitinib-resistant cells and suggests that a triple combination of FDA-approved drugs would provide a low-cost and practical strategy to overcome gefitinib resistance.


2020 ◽  
Author(s):  
Tom J. Zajdel ◽  
Gawoon Shim ◽  
Daniel J. Cohen

AbstractThere is a growing interest in bioelectric wound treatment and electrotaxis, the process by which cells detect an electric field and orient their migration along its direction, has emerged as a potential cornerstone of the endogenous wound healing response. Despite recognition of the importance of electrotaxis in wound healing, no experimental system to date demonstrates that the actual closing of a wound can be accelerated solely by the electrotaxis response itself, and in vivo systems are too complex to resolve cell migration from other healing stages such as proliferation and inflammation. This uncertainty has led to a lack of standardization between stimulation methods, model systems, and electrode technology required for device development. In this paper, we present a ‘healing-on-chip’ approach that is a standardized, low-cost, model for investigating electrically accelerated wound healing. Our device provides the first convergent field geometry used in a stimulation device. We validate this device by using electrical stimulation to close a 1.5 mm gap between two large (30 mm2) primary skin keratinocyte layers to double the rate of healing over an unstimulated tissue. This proves that convergent electrotaxis is both possible and can accelerate healing, and offers a new ‘healing-on-a-chip’ platform to explore future bioelectric interfaces.


Author(s):  
Mira Tafa ◽  
Sevim Naz Karışık ◽  
Ece Begüm Aksoy ◽  
Rüya Aslan

Cystic Fibrosis is a rare genetic disease that affects the transmission of chloride ions due to mutations in the CFTR (cystic fibrosis transmembrane conductance regulator) gene. Even though there are nearly 2000 mutations identified to be related to the condition, the most common mutation is F508del; deletion of a phenylalanine residue at 508. On the other hand, G542X which is a Class I mutation is also found very commonly and there are no modulator treatments available for it. Furthermore, it was investigated that R553X mutation can as well be corrected simultaneously with G542X mutation. Therefore, the main focus is on designing a gene therapy project that can correct all these three mutations at once by utilizing the prime editing technique via lipid-based delivery. In this way, the mutations can be edited through plasmids that were designed containing 2 pegRNAs and the Cas enzyme. To implement such an approach efficiently, both ex vivo, an animal model, and in vivo steps are to be designed. For the cell line, fibroblasts are selected due to their simplicity and low cost. The animal model of the experiment is determined to be a ferret concerning the high similarity to the human's CFTR protein and finally, the procedure will follow on a direct application in human Cystic Fibrosis patients. The plasmids are thought to be delivered through a cationic liposome that will reach the lungs with the aid of a nebulizer. At the last stage of the experimental procedure, Sanger Sequencing will be done to see if the desired edit within the CFTR has been performed successfully, and Next Generation Sequencing will be executed to see if there has been an off-target mutation in the remainder of the genome. Whereas for detecting the presence and expression of CFTR protein in humans, immunodetection with flow cytometry will be conducted.


2018 ◽  
Vol 115 (10) ◽  
pp. E2366-E2375 ◽  
Author(s):  
David Langlais ◽  
Regina Cencic ◽  
Neda Moradin ◽  
James M. Kennedy ◽  
Kodjo Ayi ◽  
...  

Cerebral malaria (CM) is a severe and rapidly progressing complication of infection by Plasmodium parasites that is associated with high rates of mortality and morbidity. Treatment options are currently few, and intervention with artemisinin (Art) has limited efficacy, a problem that is compounded by the emergence of resistance to Art in Plasmodium parasites. Rocaglates are a class of natural products derived from plants of the Aglaia genus that have been shown to interfere with eukaryotic initiation factor 4A (eIF4A), ultimately blocking initiation of protein synthesis. Here, we show that the rocaglate CR-1-31B perturbs association of Plasmodium falciparum eIF4A (PfeIF4A) with RNA. CR-1-31B shows potent prophylactic and therapeutic antiplasmodial activity in vivo in mouse models of infection with Plasmodium berghei (CM) and Plasmodium chabaudi (blood-stage malaria), and can also block replication of different clinical isolates of P. falciparum in human erythrocytes infected ex vivo, including drug-resistant P. falciparum isolates. In vivo, a single dosing of CR-1-31B in P. berghei-infected animals is sufficient to provide protection against lethality. CR-1-31B is shown to dampen expression of the early proinflammatory response in myeloid cells in vitro and dampens the inflammatory response in vivo in P. berghei-infected mice. The dual activity of CR-1-31B as an antiplasmodial and as an inhibitor of the inflammatory response in myeloid cells should prove extremely valuable for therapeutic intervention in human cases of CM.


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Jan-Philipp Kobler ◽  
Anandhan Dhanasingh ◽  
Raphael Kiran ◽  
Claude Jolly ◽  
Tobias Ortmaier

To develop skills sufficient for hearing preservation cochlear implant surgery, surgeons need to perform several electrode insertion trials inex vivotemporal bones, thereby consuming relatively expensive electrode carriers. The objectives of this study were to evaluate the insertion characteristics of cochlear electrodes in a plastic scala tympani model and to fabricate radio opaque polymer filament dummy electrodes of equivalent mechanical properties. In addition, this study should aid the design and development of new cochlear electrodes. Automated insertion force measurement is a new technique to reproducibly analyze and evaluate the insertion dynamics and mechanical characteristics of an electrode. Mechanical properties of MED-EL’s FLEX28, FLEX24, and FLEX20electrodes were assessed with the help of an automated insertion tool. Statistical analysis of the overall mechanical behavior of the electrodes and factors influencing the insertion force are discussed. Radio opaque dummy electrodes of comparable characteristics were fabricated based on insertion force measurements. The platinum-iridium wires were replaced by polymer filament to provide sufficient stiffness to the electrodes and to eradicate the metallic artifacts in X-ray and computed tomography (CT) images. These low-cost dummy electrodes are cheap alternatives for surgical training and forin vitro, ex vivo, andin vivoresearch purposes.


2020 ◽  
Vol 10 (2) ◽  
pp. 20190090 ◽  
Author(s):  
H. W. Hoyle ◽  
L. A. Smith ◽  
R. J. Williams ◽  
S. A. Przyborski

As the field of tissue engineering continues to advance rapidly, so too does the complexity of cell culture techniques used to generate in vitro tissue constructs, with the overall aim of mimicking the in vivo microenvironment. This complexity typically comes at a cost with regards to the size of the equipment required and associated expenses. We have developed a small, low-cost bioreactor system which overcomes some of the issues of typical bioreactor systems while retaining a suitable scale for the formation of complex tissues. Herein, we have tested this system with three cell populations/tissues: the culture of hepatocellular carcinoma cells, where an improved structure and basic metabolic function is seen; the culture of human pluripotent stem cells, in which the cultures can form more heterogeneous tissues resembling the in vivo teratoma and ex vivo liver tissue slices, in which improved maintenance of cellular viability is seen over the 3 days tested. This system has the flexibility to be used for a variety of further uses and has the potential to provide a more accessible alternative to current bioreactor technologies.


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