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The optimal strategy of stabilizing hemodynamic function in uncontrolled traumatic hemorrhagic shock states is unclear. Although fluid replacement is established in controlled hemorrhagic shock, its use in uncontrolled hemorrhagic shock is controversial, because it may worsen bleeding. In the refractory phase of severe hemorrhagic shock, arginine vasopressin has been shown to be beneficial in selected cases due to an increase in arterial blood pressure, shift of blood away from a subdiaphragmatic bleeding site toward the heart and brain, and decrease in fluid-resuscitation requirements. Especially in patients with severe traumatic brain injury, rapid stabilization of cardiocirculatory function is essential to ensure adequate brain perfusion, thus, to prevent neurologic damage and to improve outcome. In addition, despite wide distribution of highly developed and professional emergency medical systems in western industrialized countries, survival chances of patients with uncontrolled traumatic hemorrhagic shock in the preclinical setting are still poor. [ABSTRACT FROM AUTHOR]

Supercritical impregnation technology was applied to load acrylic intraocular lenses (IOLs) with methotrexate to produce a sustained drug delivery device to mitigate posterior capsule opacification. Drug release kinetics were studied in vitro and used to determine the drug loading. Loaded IOLs and control IOLs treated under the same operating conditions, but without drug, were implanted ex vivo in human donor capsular bags. The typical cell growth was observed and immunofluorescence staining of three common fibrosis markers, fibronectin, F-actin and α-smooth muscle actin was carried out. Transparent IOLs presenting a sustained release of methotrexate for more than 80 days were produced. Drug loading varying between 0.43 and 0.75 ± 0.03 µg drug ·mg -1 IOL were obtained when varying the supercritical impregnation pressure (8 and 25 MPa) and duration (30 and 240 min) at 308 K. The use of ethanol (5 mol%) as a co-solvent did not influence the impregnation efficiency and was even unfavorable at certain conditions. Even if the implantation of methotrexate loaded IOLs did not lead to a statistically significant variation in the duration required for a full cell coverage of the posterior capsule in the human capsular bag model, it was shown to reduce fibrosis by inhibiting epithelial-mesenchymal transformation. The innovative application presented has the potential to gain clinical relevance., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Purpose: Posterior capsule opacification (PCO) still represents the main long-term complication of cataract surgery. Research into pharmacologic PCO prophylaxis is extensive. One promising candidate drug is methotrexate (MTX). Our aim is to determine the in vitro feasibility of MTX-loaded poly(lactic-co-glycolic) (PLGA) biomatrices sprayed on intraocular lenses (IOLs) as a drug-delivery implant., Methods: Hydrophilic and hydrophobic acrylic IOLs were spray-coated with MTX-loaded PLGA. Unsprayed, solvent only, and solvent-PLGA-sprayed IOLs served as controls. All IOLs were evaluated for their growth-inhibiting properties in an in vitro anterior segment model and the ex vivo human capsular bag. The release kinetics of MTX from the IOLs was determined. The toxicity of MTX on corneal endothelial cells was evaluated by using a dye reduction colorimetric assay. MTX was also used in a scratch assay., Results: MTX-PLGA-IOL showed a significant difference in cell proliferation and migration compared with all controls in the anterior segment model (p < 0.001) and in the human capsular bag model (p = 0.04). No difference in viability was observed on corneal endothelial cells (p = 0.43; p = 0.61). MTX significantly inhibited cells in the scratch assay (p = 0.02). At all measured points, the released MTX dose remained above EC50 and below the toxic dose for the endothelium., Conclusions: In view of the strong inhibition of PCO in vitro with the lack of toxic effects on a corneal cell line, MTX encapsulating microspheres seem to be a promising method for modifying IOL.

Purpose: Numerous pharmacologic substances have been proposed for preventing posterior capsule opacification (PCO). The following trial was to compare those drugs to find more suitable options. IOL should then be modified by the pharmaceuticals as a drug-delivery device., Methods: A systematic literature search was performed to identify published substances. FHL-124 was used to determine cell proliferation and toxicity using a dye reduction test (XTT). Prescreened substances showing a reduction on cell growth without being toxic were soaked into an IOL. Those IOL were tested for their effect on PCO in an anterior-segment model and the human ex vivo capsular bag model. Toxicity on a corneal endothelial cell line (CEC-SV40) was determined. Release kinetics of methotrexate from the IOL was measured. Toxicity testing in both cell lines was done in serum-free conditions. All growth assays were exposed to 10% fetal calf serum (FCS)-supplemented medium., Results: The substances inhibited cell growth at the following EC50: caffeic acid phenethyl ester 1.6 ± 0.9 nM, disulfiram 359 ± 33 nM, methotrexate 98.0 ± 29.7 nM, rapamycin 70.2 ± 14.0 pM, and retinoic acid 1.1 ± 0.12 nM. All but disulfiram showed an effect in the anterior segment model when soaked into an IOL. Long-term inhibitory effects in the human capsular bag model were observed for caffeic acid phenethyl ester and methotrexate IOLs. Only methotrexate and disulfiram did not show any toxicity on endothelial cells. Methotrexate was released constantly from the hydrophilic IOL for 2 weeks., Conclusions: We could identify caffeic acid phenethyl ester and methotrexate in vitro as potential candidates for IOL modification for PCO prophylaxis.

Purpose: To introduce a human cell culture technique for investigating in-vitro behavior of primary epiretinal cells and membrane contraction of fibrocellular tissue surgically removed from eyes with idiopathic macular pucker., Methods: Human epiretinal membranes were harvested from ten eyes with idiopathic macular pucker during standard vitrectomy. Specimens were fixed on cell culture plastic using small entomological pins to apply horizontal stress to the tissue, and then transferred to standard cell culture conditions. Cell behavior of 400 epiretinal cells from 10 epiretinal membranes was observed in time-lapse microscopy and analyzed in terms of cell migration, cell velocity, and membrane contraction. Immunocytochemistry was performed for cell type-specific antigens., Results: Cell specific differences in migration behavior were observed comprising two phenotypes: (PT1) epiretinal cells moving fast, less directly, with small round phenotype and (PT2) epiretinal cells moving slowly, directly, with elongated large phenotype. No mitosis, no outgrowth and no migration onto the plastic were seen. Horizontal contraction measurements showed variation between specimens. Masses of epiretinal cells with a myofibroblast-like phenotype expressed cytoplasmatic α-SMA stress fibers and correlated with cell behavior characteristics (PT2). Fast moving epiretinal cells (PT1) were identified as microglia by immunostaining., Conclusions: This in-vitro technique using traction application allows for culturing surgically removed epiretinal membranes from eyes with idiopathic macular pucker, demonstrating cell behavior and membrane contraction of primary human epiretinal cells. Our findings emphasize the abundance of myofibroblasts, the presence of microglia and specific differences of cell behavior in these membranes. This technique has the potential to improve the understanding of pathologies at the vitreomacular interface and might be helpful in establishing anti-fibrotic treatment strategies.

Development of an intraocular lens (IOL) as a drug delivery device has been pursued for many years and is a promising concept in modern cataract surgery. Common postoperative conditions such as posterior capsule opacification (PCO), intraocular inflammation or the rare but severe complications of cataract surgery like endophthalmitis are potential therapeutic targets for a drug-eluting IOL. There are three techniques of pharmacological IOL modification: Firstly, surface modification of the IOL ("coating"); secondly, IOL optic modification ("soaking") and lastly, loading the IOL haptics with a slow release system. The last option does not interfere with the IOL optics at all. Therefore, a broad spectrum of pharmacological agents needs to be assessed in preclinical and clinical studies to determine which agent/IOL combination is safe and efficient. For pharmacological PCO prophylaxis, erufosine-loaded IOLs are of great clinical interest. Heparin-coated IOLs might become clinically relevant for attenuation of intraocular inflammation after cataract surgery and cefuroxime-loaded IOLs for endophthalmitis prophylaxis., (Georg Thieme Verlag KG Stuttgart · New York.)

In order to extrapolate novel therapies from the bench to the bedside (translational research), animal experiments are scientifically necessary. Swine are popular laboratory animals as their cardiorespiratory physiology is very similar to humans. Every study has to be approved by the local and/or national animal ethical committees. As swine are extremely sensitive to stress the primary goal is therefore to provide a calm, stress-free environment in both housing and experimental facilities. Swine should be properly sedated for transport and normothermia needs to be ensured. It is recommended to commence anesthesia by injecting ketamine and propofol followed by endotracheal intubation during spontaneous breathing. After intubation, anesthesia maintenance is performed with morphine or piritramide, propofol and rocuronium and routine monitoring is applied analogue to a clinical operating theater for humans. Normothermia (38.5 °C) needs to be ensured. While surgical procedures can be readily extrapolated from a human operating theater to swine, non-anesthesiologist scientists may lose the animal rapidly due to airway management problems. Vascular access can be secured by cut-downs or ultrasound-guided techniques in the inguinal and the neck region. For humane euthanasia of pigs, morphine, followed by propofol, rocuronium and potassium chloride are recommended. As radical animal right groups may threaten scientists, it is prudent that animal laboratories have unmarked entrance doors, are located in buildings that are not accessible to the public and strictly controlled access of laboratory staff is enforced. In conclusion, swine are an excellent laboratory animal for bench to bedside research and can be managed properly when basic knowledge and adequate skills on careful handling, anesthesia and surgical considerations are present.

Introduction: After cataract surgery, residual lens epithelial cells migrate and proliferate within the capsular bag resulting in posterior capsule opacification (PCO). The up-regulation of TGF-β2, EGF and FGF-2 has been identified as a key factor in PCO pathogenesis leading to actin fiber assembly and alterations in the migration pattern. In this in vitro study, the influence of Erlotinib as a selective EGFR inhibitor is investigated on the cellular features indicated, which might promote a future clinical application., Methods: Expression of EGF, FGF-2 and TGF-β2 was measured using RT-PCR and ELISA in human lens epithelial cells (HLEC). Computational data of an in vitro time lapse microscopy assay were used for statistical analysis of single cell migration with a particular focus on cell-cell interaction; cell velocity distribution; and displacement before, during and after mitosis. The effect of Erlotinib on the actin-cytoskeleton was evaluated using Alexa Fluor 488 Phalloidin and epifluorescence microscopy., Results: EGF and TGF-β2 mRNA expression and protein levels are reduced by Erlotinib, while FGF-2 expression remained stable. Overall fluidity of cell-cell interaction is less in the presence of Erlotinib compared to the control and the velocity distribution across all cells becomes less uniform within the cell cluster. After mitosis, HLEC move significantly faster without EGFR inhibition, which can be completely blocked by Erlotinib. Furthermore, Erlotinib diminishes the amount of actin stress fibers and the stress fiber diameter., Conclusion: As a novel effect of Erlotinib on HLEC, we describe the down-regulation of EGF and TGF-β2 expression, both are crucial factors for PCO development. Cellular movement displays complex alterations under EGFR inhibition, which is partly explained by actin fiber depletion. These findings further underline the role of Erlotinib in pharmacologic PCO prophylaxis.

Background: Posterior capsule opacification (PCO) represents a major challenge in the postoperative management of cataract patients. Spreading, migration and contraction of residual human lens epithelial cells play a pivotal role in the pathogenesis of PCO. Therefore, we analyzed the effect of the alkylphosphocholine (APC) erufosine on these cellular features as well as on PI3K/Akt, a crucial pathway in PCO pathogenesis., Methods: Human lens epithelial cells were cultured under standard cell culture conditions. Cell spreading was analyzed on fibronectin-coated wells and chemokinetic migration was assessed by time-lapse microscopy. For evaluation of cell-mediated collagen matrix contraction, the cells were seeded into collagen gels and incubated with an APC in different non-toxic concentrations before the surface area was measured on day 6. The activity of PI3K/Akt was assessed by an ELISA kit after incubation of the cells with different APC concentrations., Results: Human lens epithelial cell spreading and migration were attenuated by APCs as follows: 7 % spreading, 48 % migration (0.1 μM APC), and 32 % spreading, 68 % migration (1.0 μM APC). APC concentrations of 0.1 μM reduced collagen gel diameter by 5 %, and 1.0 μM by less than 1 %, compared to untreated, cell-populated gels that resulted in a cell diameter contraction of 36 %. PI3K was downregulated in a concentration-dependent manner., Conclusions: The crucial cellular features of PCO pathogenesis are attenuated by the APC erufosine via downregulation of the PI3K pathway. Thus, erufosine might become a valuable tool for pharmacologic PCO prophylaxis in the future.

Background: Only randomized clinical trials can improve the outcome of life-threatening injuries or diseases but observations from England and North America suggest that the number of such randomized clinical trials is decreasing. In this study contributions from German speaking countries with regards to randomized clinical trials in emergency medicine over the last 22 years were investigated., Methods: The Medline database was searched from January 1990 to December 2012 for prospective randomized clinical trials in the prehospital setting using the criteria "cardiac arrest", "cardiopulmonary resuscitation", "multiple trauma", "hemorrhagic shock", "head trauma", "stroke" as well as myocardial infarction and emergency medical service. Only studies originating from Germany, Austria or Switzerland were included., Results: A total of 474 studies were found and 25 studies (5.3 %) fulfilled the inclusion criteria. In the last 22 years German speaking countries have published approximately one prospective, randomized, clinical trial per year on prehospital emergency medicine. The median number of patients included in the trials was 159 (minimum 16, maximum 1,219). Most (80 %) studies originated from Germany and most (64 %) studies were conducted by anesthesiology departments. Cardiac arrest was the most frequent subject of the investigated studies. Approximately 50 % of the studies had financial support from industrial companies., Conclusion: A significant increase or decrease in the number of prospective randomized clinical trials in the out-of-hospital setting could not be found in German speaking countries despite the fact that the absolute numbers of studies had increased. Only about one prospective, randomized clinical trial with an emergency medicine core tracer diagnosis originated from Germany, Austria and Switzerland per year.

The development of an intraocular lens (IOL) as a drug delivery device has been the purpose of numerous preclinical studies and might become a future technology in cataract surgery. There are three techniques of pharmacological IOL modification: surface modification (coating), optic modification (soaking) or haptic modification with a slow-release-system. The therapeutic goals are endophthalmitis, postoperative inflammation and posterior capsule opacification.

Background: Posterior capsule opacification (PCO) is the most frequent complication after cataract surgery, leading to a loss of sight if untreated. Erlotinib might be of therapeutic interest as an effective target agent (selective EGF-tyrosin-kinase-1 inhibitor). In this in-vitro study, erlotinib was evaluated for ocular biocompatibility and its effect on cell proliferation, migration, 3D matrix contraction and spreading of human lens epithelial cells., Methods: To exclude toxic concentrations, erlotinib was assessed for its biocompatibility on five different human ocular cell types in vitro by the tetrazolium dye-reduction assay (MTT) and the Live-Dead assay. To determine its effect on human lens epithelial cell (HLE-B3) proliferation, the MTT test was performed after incubation with different concentrations of erlotinib. Chemotactic migration was analyzed with the Boyden chamber assay and chemokinetic migration was assessed by time lapse microscopy. Contraction was measured by a 3D collagen type 1 matrix contraction assay, and cell spreading was determined by measuring the cell diameter on a fibronectin coated surface., Results: The maximum non-toxic concentration of erlotinib was determined to be 100 μM in cell culture. Erlotinib potently inhibits human lens epithelial cell proliferation, with an IC50 of about 10 μM (8.8 μM ± 0.9 μM SD; r (2) =0.94). Chemotactic migration (p=0.004) and chemokinetic migration (p=0.001) were reduced significantly in a concentration-based manner. Erlotinib prevented human lens epithelial cells from matrix contraction (p=0.001) and cell-spreading (p=0.001)., Conclusions: Erlotinib might become of clinical relevance for PCO prophylaxis in the future since it displayed good biocompatibility on ocular cells and mitigated human lens epithelial cell proliferation, migration, contraction, and spreading in vitro. Further studies are warranted to evaluate its potential for clinical application.

Background: Automated ventilation devices are becoming more popular for emergency ventilation, but there is still not much experience concerning the optimal ventilation mode., Methods: In a bench model representing a non-intubated patient in respiratory and cardiac arrest, we compared a pressure-cycled with a time- and volume-cycled automated ventilation device in their completely automated modes. The main study endpoints were inspiratory time, respiratory rate, stomach inflation, and lung tidal volumes., Results: The pressure-cycled device inspired for 6.7 s in the respiratory arrest setting (respiratory rate 5.6/min), and never reached its closing pressure in the cardiac arrest setting (respiratory rate 1 breath/min). The time- and volume-cycled device inspired in both settings for 1.7 s (respiratory rate 13 breaths/min). In the respiratory arrest setting, mask leakage was 620 ± 20 mL for the pressure-cycled device vs. 290 ± 10 mL for the time- and volume-cycled device (p < 0.0001); lung tidal volume was 1080 ± 50 mL vs. 490 ± 20 mL, respectively (p < 0.0001); and there was no stomach inflation for either device. In the cardiac arrest setting, pressure-cycled device mask leakage was 5460 ± 60 mL vs. 240 ± 20 mL (p < 0.0001) for the time- and volume-cycled device (p < 0.0001); stomach inflation was 13,100 ± 100 mL vs. 90 ± 10 mL, respectively (p < 0.0001); and lung tidal volume 740 ± 60 mL vs. 420 ± 20 mL, respectively (p < 0.0001)., Conclusion: In a simulated respiratory arrest setting, ventilation with an automated pressure-cycled ventilation device resulted in lower respiratory frequency and larger tidal volumes compared to a time- and volume-cycled device. In a simulated cardiac arrest setting, ventilation with an automated pressure-cycled ventilation device, but not a time- and volume-cycled device, resulted in continuous gastric insufflation., (Copyright © 2011 Elsevier Inc. All rights reserved.)

PURPOSE. To elucidate the role of Toll-like receptor 3 (TLR3) in the pathogenesis of age-related macular degeneration (AMD) and to investigate the effect of alkylphosphocholines (APCs) on the TLR3-mediated expression of cytokines and growth factors in human retinal pigment epithelial (RPE) cells. METHODS. Confluent cultures of human RPE cells (ARPE-19) were stimulated with poly (I:C) RNA as a well-established ligand for TLR3. Cytokine profiles were determined by RT-PCR on the activation of TLR3. RPE cells were transfected with siRNA specific for TLR3 and RIG-1 to determine the receptors involved. The effect of preincubation of RPE cells with APCs on the expression level of target genes was assessed. RESULTS. Poly (I:C) RNA stimulation led to a dose-dependent increase in the expression of TLR3 and RIG-I. A significant increase in expression levels of IL-6, TNF-α, IL-8, MCP-1, ICAM-1, and BFGF was observed after poly (I:C) RNA stimulation (P < 0.05). This effect was time and dose dependent. No effect on PEDG or VEGF expression was seen. Transfection of RPE cells with siRNA specific for TLR3 reduced poly (I:C) RNA-induced mRNA expression of the genes (P < 0.05). Preincubation of RPE cells with APCs significantly reduced the poly (I:C) RNA-induced expression of the target genes (P < 0.05). CONCLUSIONS. The authors demonstrate that the expression of proinflammatory cytokines and chemokines in RPE cells depends on the activation of TLR3. The induction of downstream gene expression is blocked by siRNA specific for TLR3 and alkylphosphocholines. Therefore, TLR3 should be considered a novel target in AMD therapy.

Background: Posterior capsule opacification (PCO) is one of the major concerns in modern cataract surgery. Ten years after successful surgery, Nd:YAG capsulotomy is required in up to 42% of patients with an acrylic sharp-edged intraocular lens (IOL). Some accommodative and multifocal IOLs display even higher capsulotomy rates. Pharmacologic prophylaxis with alkylphosphocholines (APCs) could be a novel option in PCO prevention., Methods: The human lens epithelial cell line HLE-B3 served as an in-vitro model. After incubation with APCs in different concentrations (0.01, 0.1, and 1 mM), the trypan blue exclusion assay and the live/dead test were performed at serum concentrations of only 5%. Cell proliferation was assessed with the MTT test. Evaluation of cell attachment was done with fibronectin- and laminin-coated wells., Results: APCs can inhibit the proliferation of human lens epithelial cells in the presence of only 5% serum in a dose-dependent manner. Proliferation inhibition of 60% and attachment inhibition of about 50% were reached at concentrations of 0.1 µM., Conclusion: APCs inhibit proliferation and attachment of human lens epithelial cells in nontoxic concentrations in vitro. The substance can be applied topically, and an intraoperative application for pharmacologic PCO prophylaxis is feasible.

The evolution of trauma care is driven by a synergistic relationship between civilian and military medical systems. Although the characteristics of civilian injuries differ from those encountered on the battlefield, the pathophysiologic process of dying is the same and dominated by exsanguination and central nervous trauma. As such, therapies that interfere with the physiologic ability to compensate hemorrhage may play a key role to buy time until hemostatic surgery can be initiated. From a variety of remedies with the potential to prolong the compensation phase or to reverse the decompensation phase of shock, arginine vasopressin (AVP) is one of the most promising and best-evaluated drugs. Animal studies and various case report series provide some evidence that AVP may improve blood pressure even when conventional therapies fail, thus preventing hypovolemic cardiac arrest and enabling resuscitation from fatal hemorrhage. On the basis of this civilian experience, it seems reasonable to consider AVP for hypotensive resuscitation in the austere, resource-constrained battlefield environment. However, the significance of AVP as a rescue medication for life-threatening hemorrhage has yet to be proven.

Background: Alkylphosphocholines (APCs) are synthetic phospholipid derivatives, and have been demonstrated to inhibit ocular cell proliferation in vitro and in vivo. Currently, they are applied clinically for their antitumoral and antiparasitic properties, but have not yet been implemented for clinical use in proliferative ophthalmic disorders. The purpose of this study was to assess the safety of APC in the ex vivo model of the isolated perfused vertebrate retina., Methods: Bovine retina preparations were perfused with an oxygen pre-equilibrated standard solution. The electroretinogram (ERG) was recorded using Ag/AgCl-electrodes. After recording stable b-wave amplitudes, an APC was applied at the following concentrations to the nutrient solution: 0.25 microM, 2.5 microM and 25 microM. To investigate the effects of APC on photoreceptor function, a test series at the same concentrations was performed to evaluate the effects of APC on the a-wave amplitude. Aspartate at a concentration of 1 mM was added to the nutrient solution to obtain stable a-wave amplitudes. Thereafter, APC was applied at the same concentrations to the nutrient solution. The recovery of the ERG amplitudes was followed up for 75 minutes., Results: No reduction of the a- and b-wave amplitude was found at the end of the exposure time with APC added in each test series. No differences were found between the ERG amplitudes before and after application of APC at the end of the washout., Conclusions: In the ex vivo model of the isolated perfused vertebrate retina, APC has proved to be a safe compound in the concentrations applied. Thus, APCs should further be considered as promising candidates for future clinical applications in ophthalmology.

Aims: To review anaesthesia in prehospital emergencies and in the emergency room, and to discuss guidelines for anaesthesia indication; pre-oxygenation; anaesthesia induction and drugs; airway management; anaesthesia maintenance and monitoring; side effects and training., Methods: A literature search in the PubMed database was performed and 87 articles were included in this non-systematic review., Conclusions: For pre-oxygenation, high-flow oxygen should be delivered with a tight-fitting face-mask provided with a reservoir. In haemodynamically unstable patients, ketamine may be the induction agent of choice. The rocuronium antagonist sugammadex may have the potential to make rocuronium a first-line neuromuscular blocking agent in emergency induction. An experienced health-care provider may consider prehospital anaesthesia induction. A moderately experienced health-care provider should optimise oxygenation, fasten hospital transfer and only try to intubate a patient in extremis. If intubation fails twice, ventilation should be resumed with an alternative supra-glottic airway or a bag-valve-mask device. A lesser experienced health-care provider should completely refrain from intubation, optimise oxygenation, fasten hospital transfer and only in extremis ventilate with an alternative supra-glottic airway or a bag-valve-mask device. With an expected difficult airway, the patient should be intubated awake. With an unexpected difficult airway, bag-valve-mask ventilation should be resumed and an alternative supra-glottic airway device inserted. Senior help should be called early. In a "can-not-ventilate, can-not-intubate" situation an alternative airway should be tried and if unsuccessful because of severe upper airway pathology, a surgical airway should be performed. Ventilation should be monitored continuously with capnography. Clinical training is important to increase airway management skills., (Copyright 2009 Elsevier Ireland Ltd. All rights reserved.)