["I will do laparoscopy somewhere else" : Total, highly immersive virtual reality without side effects?]

BACKGROUND

For virtual reality laparosopic simulation we developed a new, highly immersive simulation mode. The goal of the current pilot study was to investigate if kinetosis or other negative vegetative side effects can be caused by a total virtual training set-up (TVRL).

METHODS

In this study 20 participants with varying degrees of expertise in laparoscopy performed 3 tasks (i.e. ring exchange, fine dissection and cholecystectomy) in regular (VRL) and immersive mode (TVRL) with a head-mounted display (HMD) on a laparoscopic simulator. Aside from performance scores, the heart rate was recorded and the occurrence of vertigo was investigated.

RESULTS

Surgical performance was independent of the VR mode (VRL or TVRL). Participants' heart rate was higher in TVRL without reaching statistical significance. Kinetosis occurred in two participants (10%) with a history of motion sickness.

CONCLUSION

Laparoscopic training can take place in a total virtual environment with limited nagative vegetative side effects. Special attention should be paid to participants with a history of motion sickness. The development of TVRL enables new perspectives for surgical training.

[Indications for transplantation and bridging procedures for primary hepatobiliary malignancies]

Primary hepatobiliary malignancies are hepatocellular carcinoma, cholangiocarcinoma and the rare hepatocellular cholangiocarcinoma (mixed tumor). The indications for liver transplantation and the oncological prognosis differ considerably between these tumor entities. Treatment and decision making for these tumors are often complicated by an underlying chronic liver disease. The aim of this review is to delineate the indications for transplantation and bridging therapies for each cancer entity as well as to highlight some aspects pertinent to transplantation, such as the principles of organ allocation.

Change from Hybrid to Fully Minimally Invasive and Robotic Esophagectomy is Possible without Compromises

BACKGROUND

 The incidence of esophageal carcinoma is increasing in the western world, and esophageal resection is the essential therapy. Several studies report advantages of minimally invasive esophagectomies (MIEs) versus conventional open procedures (OPs). The benefits of the use of fully MIE or robot-assisted MIE (RAMIE) compared with the hybrid approaches (laparoscopic gastric preparation and open transthoracic esophagectomy) remain unclear.

METHODS

 Between July 2015 and August 2017, the data of 75 patients with esophageal carcinoma were prospectively registered. Of the 75 patients, 25 treated with a hybrid MIE (hybrid), 25 with total MIE (MIE), and 25 with RAMIE. All patients were operated by the same specialized surgeon in our center with an identical anastomotic technique (circular stapler).

RESULTS

 The overall 30- and 90-day mortality rates were 0 and 1.33% (1/75), respectively. Total hospital stay (p = 0.262), intensive care unit stay (p = 0.079), number of resected lymph nodes (p = 0.863), and R status (p = 0.132) did not differ statistically between the groups. However, pneumonia and wound infections occurred significantly and more frequently in the hybrid group compared with the minimally invasive groups (MIE and RAMIE) (p = 0.046 and p = 0.003, respectively).

CONCLUSION

 Comparable results regarding morbidity and short-term outcome could be achieved in the MIE and RAMIE groups compared with the hybrid group. The data indicate that the learning curve is low in surgeons changing the technique form hybrid esophagectomy to fully MIE. Additionally, the total minimally invasive approaches seem to be associated with a low incidence of complications such as pneumonia and wound infections.

Calibration of a Lyophilized Pooled Plasma as Candidate Reference Plasma for Standardization of the Prothrombin Time Ratio

The prothrombin time (PT), obtained from a fresh normal plasma pool (FPP), is the basis both for the establishment of the 100% activity (normal plasma) and for the ratio calculation used in the International Normalized Ratio (INR) according to the recommendations of the ICSH/ICTH (6). Today the PT of lyophilized normal plasma pools are successfully used as reference for the assessment of samples in proficiency studies. However, a lack of comparability is to be recognized. Therefore the Committee of Hematology of the German Association of Diagnostics’ and Diagnostic Instruments’ Manufacturers (VDGH) decided to produce a candidate reference plasma (VDGH Reference Plasma) which was calibrated against fresh normal plasma pools in an international study.

The basic calibration was performed by using the same certified BCR thromboplastin (BCT/099) by all participants. The endpoint was determined manually and by using the coagulometer Schnitger-Gross. In additional testings each participant used his own routine thromboplastins and methods. Calculating the ratio [PT VDGH Reference Plasma (sec)/PT fresh normal plasma pool (sec)] the VDGH Reference Plasma showed a deviation from the average fresh normal plasma pool of 1.05 both with the BCT/099 and with all thromboplastins. There were obtained some statistical differences between “plain” and “combined’’ (added factor V and fibrinogen) thromboplastins. No statistical difference was found between the different endpoint measurement methods (manual, mechanical, optical).

In spite of these statistical deviations the VDGH Reference Plasma can be used for the standardization of the PT-normal (100%) value with different ratios for plain (1.06) and combined (1.02) thromboplastins. The manufacturers will use this VDGH Reference Plasma for the calibration of their commercially available calibration plasmas, which allows the user of such a material to calculate a calibrated 100% PT value.

International Normalized Ratio (INR) – Proficiency Tests by ÖQUASTA for the Prothrombin Time

Although the INR (International Normalized Ratio)/ISI (International Sensitivity Index) scheme was introduced by the WHO (13) in 1983 to standardize the PT (prothrombin time) expression, the use of the non-comparable percent of a normal fresh plasma, seconds or PT-ratio (patient plasma/normal plasma) is still common in the coagulation laboratories. The availability of the INR/ISI scheme to monitor quality control of the laboratories in a reagent and method independent manner was examined by the comparison of 13 PT proficiency tests carried out by the ÖQUASTA (Austrian Society of Quality Assurance and Standardization of Diagnostic Medical Investigations).

In each proficiency test approximately 250 laboratories had to determine the PT of two to three lyophilized plasma samples with their routinely used reagents and methods. The INR mean values of the AK-plasmas (plasmapools from patients under anticoagulant therapy) were between 2 and 5. The determined data and the calculated INR-values were returned to the ÖQUASTA.

According to the INR/ISI scheme, all data should be considered as belonging to the same collective (TC = total collective). To prove this demand, additionally each reagent and method was evaluated separately (SC = single collective). It could be shown that the INR mean values obtained from all data and using TC or SC evaluation are nearly equivalent indicating that the TC evaluation is suitable for use in proficiency tests.

The aim of a better comparability of the PT values can not only be reached by the laboratories through the use of the INR/ISI scheme. Additionally, the manufacturer are asked to standardize their ISI and 100% value determination. The manufacturer took this into account by establishing a candidate reference plasma (5).

It could be shown that the introduction of the INR was not only an important step forward in terms of standardization and comparability of different thromboplastin reagents, but also in the quality control of the laboratories checked in proficiency tests in Austria.

Cecal Resection with Bipolar Sealing Devices in a Rat Model

Background: Bipolar sealing devices are routinely used to seal blood vessels. The aim of the study is to evaluate the feasibility and safety of colonic sealing with the use of the bipolar energy devices in rats as model for experimental appendectomy. Methods: Seventy-five male Wistar rats underwent a cecal resection with four different bipolar sealing devices or a linear stapler. The harvesting procedure was performed immediately or at postoperative day (POD) 7. The sealing front bursting pressure (BP) was measured in both groups. At POD7, the resection line was clinically examined and the hydroxyproline (HDP) levels were determined. Hematoxylin and Eosin (H&E) staining was used for histopathological evaluation of the sealing front as well. Results: There was no mortality and no insufficiency. The BPs between the bipolar sealing devices showed no statistical differences. The early phase of the seal (POD 0) provides a low BP with an 30.8% increase until POD 7. The BPs in the stapler group showed significant better values. The hydroxyproline levels did not differ statistically between the groups. Histopathologically, there were more signs of ischemic necrosis in the stapler group than in the sealing devices groups. Conclusion: The resection and sealing of the cecum as an experimental appendectomy model with the use of bipolar energy devices proved feasible and safe in rats. The different energy devices in this study produce comparable results. To justify clinical practice in humans, several studies on the underlying mechanisms of early stage wound healing are needed.

Antiviral T Cells for Adenovirus in the Pretransplant Period: A Bridge Therapy for Severe Combined Immunodeficiency

Viral infections can be life threatening in patients with severe combined immunodeficiency (SCID) and other forms of profound primary immunodeficiency disorders both before and after hematopoietic stem cell transplantation (HSCT). Adoptive immunotherapy with virus-specific T cells (VSTs) has been utilized in many patients in the setting of HSCT, but has very rarely been attempted for treatment of viral infections before HSCT. Here we describe the use of VSTs in an infant with RAG1 SCID who had developed disseminated adenovirus which failed to improve on cidofovir. Adenovirus cleared following 2 doses of VSTs and marrow infusion from a matched unrelated donor, without incidence of graft versus host disease. T cell receptor-b sequencing demonstrated expansion of adenovirus-specific T cell fraction of the VSTs, suggesting that infusion facilitated viral clearance. This report suggests that VSTs are likely safe in the pre-HSCT period, and may be a useful bridge therapy for infants with SCID and persistent viral infections.

Pretransplant coronary artery disease is a predictor for myocardial infarction and cardiac death after liver transplantation

BACKGROUND

Cardiovascular disease is a serious problem of liver transplant (LT) recipients because of increased cardiovascular risk due to immunosuppressive therapy, higher age, intraoperative risk and comorbidities (such as diabetes and nicotine abuse). Reported frequency of cardiovascular events after LT shows a high variability between different LT cohorts. Our aim was to analyze a cohort of LT recipients from a single center in Germany to evaluate frequency of the cardiovascular endpoints (CVE) myocardial infarction and/or cardiac death after LT and to investigate correlations of CVE post LT with pretransplant patient characteristics.

PATIENTS

In total, data from 352 LT patients were analyzed. Patients were identified from an administrative transplant database, and all data were retrieved from patients' charts and reports.

RESULTS

During the median follow-up of 4.0 (0-13) years, 10 cases of CVE were documented (six myocardial infarctions and four coronary deaths). The frequency of CVE did not differ according to classic cardiovascular risk factors such as body mass index (p=0.071), total cholesterol (p=0.533), hypertension (p=0.747), smoking (p=1.000) and pretransplant diabetes mellitus (p=0.146). In patients with pretransplant coronary heart disease (n=24; 6.8%) CVE were found more frequently (p=0.024).

CONCLUSION

In summary, we found a rate of 2.8% CVE after LT in a German transplant cohort. Pretransplant CHD was the only risk factor for CVE, but showed no significant impact on overall survival.

Designing smartphone mental health applications for emergency service workers

Background

Emergency service workers are often exposed to trauma and have increased risk of a range of mental health (MH) conditions. Smartphone applications have the potential to provide this group with effective psychological interventions; however, little is known about the acceptability and preferences regarding such initiatives.

Aims

To describe the preferences and opinions of emergency service workers regarding the use of smartphone MH applications and to examine the impact of age on these preferences.

Methods

Participants were recruited from four metropolitan Fire and Rescue NSW stations and responded to questionnaire items covering three key domains: current smartphone use, potential future use and preferences for design and content as well as therapeutic techniques.

Results

Overall, approximately half the sample (n = 106) claimed they would be interested in trying a tailored emergency-worker MH smartphone application. There were few differences between age groups on preferences. The majority of respondents claimed they would use an app for mental well-being daily and preferred terms such as 'well-being' and 'mental fitness' for referring to MH. Confidentiality, along with a focus on stress, sleep, exercise and resiliency were all considered key features. Behavioural therapeutic techniques were regarded most favourably, compared with other therapies.

Conclusions

Emergency workers were interested in utilizing smartphone applications focused on MH, but expressed clear preferences regarding language used in promotion, features required and therapeutic techniques preferred.

Heteroaryl bismuthines: a novel synthetic concept and metalπ heteroarene interactions

The alkoxide Bi[OCMe₂(2-C₄H₃S)]₃ (1) is formed by the reaction of three equiv. of the alcohol HOCMe₂(2-C₄H₃S) with Bi(O^tBu)₃ and subsequent hydrolysis provides the bismuth oxido cluster [Bi₄O₂{OCMe₂(2-C₄H₃S)}₈] (2). In contrast, the reaction of Bi(O^tBu)₃ and Bi[N(SiMe₃)₂]₃ with the silanols HOSiMe₂(2-C₄H₃X) (X = O, S, Se, and NMe), HOSiMe₂(2-C₄H₂S-5-SiMe₃) and HOSiMe₂(3-C₄H₃S) leads to the formation of tris(heteroaryl)bismuthines Bi(2-C₄H₂X-5-R)₃ [where X = O, R = H (3); X = S, R = H (4); X = S, R = SiMe₃ (5); X = NMe, R = H (6); X = Se, R = H (7)] and Bi(3-C₄H₃S)₃ (8). For the silanols, bismuth-carbon bond formation is observed rather than silanol-alcoholate or silanol-amide exchange. The structures of compounds 1, 2, and 4-7a in the solid state were established by single crystal X-ray diffraction and all compounds except 5 show London dispersion type bismuthπ heteroarene interactions. For the bismuthine Bi(2-C₄H₃Se)₃ (7), two polymorphs were isolated depending on the conditions of crystallization. At 8 °C, polymorph I (7a) crystallizes from an n-hexane solution in the triclinic space group P1[combining macron], whereas polymorph II (7b) crystallizes at 20 °C from a CH₂Cl₂/n-pentane solution in the monoclinic space group P2₁/c. The heteroaryl bismuthines 3 and 4 exhibit 2D network structures as a result of bismuthπ heteroarene interactions, whereas for the pyrrole derivative 6 the dispersion type interactions provide separated dimers.

[Transparent operative training in visceral surgery : Analysis at a German university medical center]

BACKGROUND

Practical operative training in the discipline of visceral surgery is currently under discussion. Aside from surveys, data on this topic in Germany are sparse. The aim of the study was an objective collation of surgical residents' practical training in the operating room in our department.

METHODS

All surgical cases from 2015 were prospectively included. Procedures were stratified into resident and non-resident operations and complex cases with sub-steps which could potentially be performed by residents. We analyzed whether an operation or surgical sub-steps were performed by a resident. If this was not achieved, the reasons were analyzed. An anonymous online survey was conducted among employees in the surgery department regarding surgical training.

RESULTS

Out of 2896 surgical cases 1141 (39.4 %) were classified as potential resident training operations, which were actually performed by a resident in 743 cases (65.1 %). The survey showed an underestimation of this proportion, where sub-steps were assisted in 30.3 % (n = 265) of 876 potential cases. This proportion significantly increased during the observation period (p < 0.001); however, it was highly overestimated by residents as well as fellows and senior consultants. Often organizational reasons were responsible when resident operations or sub-steps were not performed by a trainee (13.1 % and 30.0 %, respectively).

CONCLUSION

The monocentric analysis per se resulted in an improvement in practical surgical training. In the training environment, assisting with sub-steps provides a great potential. Multicenter studies are needed.

Human papilloma virus-specific T cells can be generated from naïve T cells for use as an immunotherapeutic strategy for immunocompromised patients

Human papilloma virus (HPV) is a known cause of cervical cancer, squamous cell carcinoma and laryngeal cancer. Although treatments exist for HPV-associated malignancies, patients unresponsive to these therapies have a poor prognosis. Recent findings from vaccine studies suggest that T-cell immunity is essential for disease control. Because Epstein-Barr Virus (EBV)-specific T cells have been highly successful in treating or preventing EBV-associated tumors, we hypothesized that the development of a manufacturing platform for HPV-specific T cells from healthy donors could be used in a third-party setting to treat patients with high-risk/relapsed HPV-associated cancers. Most protocols for generating virus-specific T cells require prior exposure of the donor to the targeted virus and, because the seroprevalence of high-risk HPV types varies greatly by age and ethnicity, manufacturing of donor-derived HPV-specific T cells has proven challenging. We, therefore, made systematic changes to our current Good Manufacturing Practice (GMP)-compliant protocols to improve antigen presentation, priming and expansion for the manufacture of high-efficacy HPV-specific T cells. Like others, we found that current methodologies fail to expand HPV-specific T cells from most healthy donors. By optimizing dendritic cell maturation and function with lipopolysaccharide (LPS) and interferon (IFN)γ, adding interleukin (IL)-21 during priming and depleting memory T cells, we achieved reliable expansion of T cells specific for oncoproteins E6 and E7 to clinically relevant amounts (mean, 578-fold expansion; n = 10), which were polyfunctional based on cytokine multiplex analysis. In the third-party setting, such HPV-specific T-cell products might serve as a potent salvage therapy for patients with HPV-associated diseases.

Cobalt and manganese carboxylates for metal oxide thin film deposition by applying the atmospheric pressure combustion chemical vapour deposition process

Coordination complexes [M(O₂CCH₂OC₂H₄OMe)₂] (M = Co, 4; M = Mn, 5) are accessible by the anion exchange reaction between the corresponding metal acetates [M(OAc)₂(H₂O)₄] (M = Co, 1; M = Mn, 2) and the carboxylic acid HO₂CCH₂OC₂H₄OMe (3). IR spectroscopy confirms the chelating or μ-bridging binding mode of the carboxylato ligands to M(ii). The molecular structure of 5 in the solid state confirms a distorted octahedral arrangement at Mn(ii), setup by the two carboxylato ligands including their α-ether oxygen atoms, resulting in an overall two-dimensional coordination network. The thermal decomposition behavior of 4 and 5 was studied by TG-MS, revealing that decarboxylation occurs initially giving [M(CH₂OC₂H₄OMe)₂], which further decomposes by M–C, C–O and C–C bond cleavages. Complexes 4 and 5 were used as CCVD (combustion chemical vapour deposition) precursors for the deposition of Co₃O₄, crystalline Mn₃O₄ and amorphous Mn₂O₃ thin films on silicon and glass substrates. The deposition experiments were carried out using three different precursor solutions (0.4, 0.6 and 0.8 M) at 400 °C. Depending on the precursor concentration, particulated layers were obtained as evidenced by SEM. The layer thicknesses range from 32 to 170 nm. The rms roughness of the respective films was determined by AFM, displaying that the higher the precursor concentration, the rougher the Co₃O₄ surface is (17.4–43.8 nm), while the manganese oxide films are almost similar (6.2–9.8 nm).

Complexes [M(O₂CCH₂OC₂H₄OMe)₂] (M = Co, Mn) were synthesized characterised regarding their thermal behaviour. They were used as precursors for deposition of rough Co₃O₄ and smooth Mn₂O₃/Mn₃O₄ thin films via the CCVD process.

Transcutaneous sacral nerve stimulation for intraoperative verification of internal anal sphincter innervation

BACKGROUND

The current standard for pelvic intraoperative neuromonitoring (pIONM) is based on intermittent direct nerve stimulation. This study investigated the potential use of transcutaneous sacral nerve stimulation for non-invasive verification of pelvic autonomic nerves.

METHODS

A consecutive series of six pigs underwent low anterior rectal resection. For transcutaneous sacral nerve stimulation, an array of ten electrodes (cathodes) was placed over the sacral foramina (S2 to S4). Anodes were applied on the back, right and left thigh, lower abdomen, and intra-anally. Stimulation using the novel method and current standard were performed at different phases of the experiments under electromyography of the autonomic innervated internal anal sphincter (IAS).

KEY RESULTS

Transcutaneous stimulation induced increase of IAS activity could be observed in each animal under specific cathode-anode configurations. Out of 300 tested configurations, 18 exhibited a change in the IAS activity correlated with intentional autonomic nerve damage. The damage resulted in a significant decrease of the relative area under the curve of the IAS frequency spectrum (P<.001). Comparison of the IAS spectra under transcutaneous and direct stimulation revealed no significant difference (after rectal resection: median 5.99 μV•Hz vs 7.78 μV•Hz, P=.12; after intentional nerve damage: median -0.27 μV•Hz vs 3.35 μV•Hz, P=.29).

CONCLUSIONS AND INFERENCES

Non-invasive selective transcutaneous sacral nerve stimulation could be used for verification of IAS innervation.