The effect of surgical strategy in difficult cholecystectomy cases on postoperative complications outcome: a value-based healthcare comparative study.

BACKGROUND: In patients undergoing laparoscopic cholecystectomy (LC) for complicated biliary disease, complication rates increase up to 30%. The aim of this study is to assess the effect of differences in surgical strategy comparing outcome data of two large volume hospitals. METHODS: A prospective database was created for all the patients who underwent a LC in two large volume hospitals between January 2017 and December 2018. In cases of difficult cholecystectomy in clinic A, regular LC or conversion were surgical strategies. In clinic B, laparoscopic subtotal cholecystectomy was performed as an alternative in difficult cases. The difficulty of the cholecystectomy (score 1-4) and surgical strategy (regular LC, subtotal cholecystectomy, conversion) were scored. Postoperative complications, reinterventions, and ICU admission were assessed. For predicting adverse postoperative complication outcomes, uni- and multivariable analyses were used. RESULTS: A total of 2104 patients underwent a LC in the study period of which 974 were from clinic A and 1130 were from clinic B. In total, 368 procedures (17%) were scored as a difficult cholecystectomy. In clinic A, more conversions were performed (4.4%) compared to clinic B (1.0%; p < 0.001). In clinic B, more subtotal laparoscopic cholecystectomies were performed (1.8%) compared to clinic A (0%; p = < 0.001). Overall complication rate was 8.2% for clinic A and 10.2% for clinic B (p = 0.121). Postoperative complication rates per group for regular LC, conversion, and subtotal cholecystectomy in difficult cholecystectomies were 45 (15%), 12 (24%), and 7 (35%; p = 0.035), respectively. The strongest predictor for Clavien-Dindo grade 3-5 complication was subtotal cholecystectomy. CONCLUSION: Surgical strategy in case of a difficult cholecystectomy seems to have an important impact on postoperative complication outcome. The effect of a subtotal cholecystectomy on complications is of great concern.

Point Absorber Limits to Future Gravitational-Wave Detectors.

High-quality optical resonant cavities require low optical loss, typically on the scale of parts per million. However, unintended micron-scale contaminants on the resonator mirrors that absorb the light circulating in the cavity can deform the surface thermoelastically and thus increase losses by scattering light out of the resonant mode. The point absorber effect is a limiting factor in some high-power cavity experiments, for example, the Advanced LIGO gravitational-wave detector. In this Letter, we present a general approach to the point absorber effect from first principles and simulate its contribution to the increased scattering. The achievable circulating power in current and future gravitational-wave detectors is calculated statistically given different point absorber configurations. Our formulation is further confirmed experimentally in comparison with the scattered power in the arm cavity of Advanced LIGO measured by in situ photodiodes. The understanding presented here provides an important tool in the global effort to design future gravitational-wave detectors that support high optical power and thus reduce quantum noise.

Device updates successfully reduce T­wave oversensing and inappropriate shocks in subcutaneous ICD patients.

AIMS: To analyse the impact of device and software updates on the prevention of T­wave oversensing (TWOS) and inappropriate shocks (IS) in subcutaneous ICD (S-ICD) patients. BACKGROUND: TWOS is a feared complication after implantation. It may lead to harmful IS. To date, specific strategies to reduce these events are lacking. METHODS: In this retrospective single-centre trial we analysed 146 S­ICD patients who were implanted between 2010 and 2016. In all eligible consecutive patients (n = 139), follow-up of at least 6 weeks was studied. The incidence of TWOS/IS was analysed in patients receiving a 2nd generation S­ICD (Emblem-S-ICD) between 2014 and 2016 (Emblem). Their outcome was compared with a control group (SQ) treated with the SQ1010 device between 2010 and 2014, who were followed up for a maximum of 2 years. Furthermore, to test if the software update SMR8 reduces inappropriate shocks in the SQ1010-S-ICD population, the incidence of TWOS/IS was evaluated before and after update installation. RESULTS: Basic characteristics and indications for S­ICD implantation were similar in both groups. However, the cumulative incidence of TWOS/IS was significantly decreased in Emblem vs. SQ (SQ: 15.4%, n = 14/91 vs. Emblem 4.2%, n = 2/48; p = 0.049). Furthermore, with regards to the SQ population we also observed a trend towards a significant reduction of TWOS/IS after installation of the software update SMR8 in 2014 (before update: 13.4%, n = 11/82 vs. after update: 4.6%, 3/65, p = 0.07). CONCLUSION: 2nd generation devices but probably also the SMR8 software update reduce the incidence of TWOS/IS in S­ICD patients.

A virtual experiment on pedestrian destination choice: the role of schedules, the environment and behavioural categories.

Which locations pedestrians decide to visit and in what order drives circulation patterns in pedestrian infrastructure. Destination choice is understood to arise from individuals trading off different factors, such as the proximity and busyness of destinations. Here, a virtual experiment is used to investigate whether this behaviour depends on the layout of buildings, whether planned or imposed destination schedules influence decisions and whether it is possible to distinguish different choice behaviour strategies in pedestrian populations. Findings suggest that virtual experiments can consistently elicit a range of destination choice behaviours indicating the flexibility of this experimental paradigm. The experimental approach facilitates changing the environment layout while controlling for other factors and illustrates this in itself can be important in determining destination choice. Destination schedules are found to be relevant both when imposed or generated by individuals, but adherence to them varies across individuals and depends on prevailing environmental conditions, such as destination busyness. Different destination choice behaviour strategies can be identified, but their properties are sensitive to the detection methods used, and it is suggested such behaviour classification should be informed by specific use-cases. It is suggested that these contributions present useful starting points for future research into pedestrian destination choice.

The ubiquitin ligase F-box/G-domain protein 1 promotes the degradation of the disease-linked protein torsinA through the ubiquitin-proteasome pathway and macroautophagy.

DYT1 dystonia is a dominantly inherited, disabling neurological disorder with low penetrance that is caused by the deletion of a glutamic acid (ΔE) in the protein torsinA. We previously showed that torsinA(wt) is degraded through macroautophagy while torsinA(ΔE) is targeted to the ubiquitin-proteasome pathway (UPP). The different catabolism of torsinA(wt) and (ΔE) potentially modulates torsinA(wt):torsinA(ΔE) stoichiometry. Therefore, gaining a mechanistic understanding on how the protein quality control machinery clears torsinA(ΔE) in neurons may uncover important regulatory steps in disease pathogenesis. Here, we asked whether F-box/G-domain protein 1 (FBG1), a ubiquitin ligase known to degrade neuronal glycoproteins, is implicated in the degradation of torsinA(ΔE) by the UPP. In a first set of studies completed in cultured cells, we show that FBG1 interacts with and influences the steady-state levels of torsinA(wt) and (ΔE). Interestingly, FBG1 achieves this effect promoting the degradation of torsinA not only through the UPP, but also by macroautophagy. To determine the potential clinical significance of these findings, we asked if eliminating expression of Fbg1 triggers a motor phenotype in torsinA(ΔE) knock in (KI) mice, a model of non-manifesting DYT1 mutation carriers. We detected differences in spontaneous locomotion between aged torsinA(ΔE) KI-Fbg1 knock out and control mice. Furthermore, neuronal levels of torsinA were unaltered in Fbg1 null mice, indicating that redundant systems likely compensate in vivo for the absence of this ubiquitin ligase. In summary, our studies support a non-essential role for FBG1 on the degradation of torsinA and uncover a novel link of FBG1 to the autophagy pathway.

Transcriptional and proteomic profiling in a cellular model of DYT1 dystonia.

DYT1, the most common inherited dystonia, is caused by a common dominant mutation in the TOR1A gene that leads to a glutamic acid deletion in the protein torsinA. Wild-type torsinA locates preferentially in the endoplasmic reticulum while the disease-linked mutant accumulates in the nuclear envelope. As a result, it has been proposed that DYT1 pathogenesis could result either from transcriptional dysregulation caused by abnormal interactions of mutant torsinA with nuclear envelope proteins, or from a loss of torsinA function in the endoplasmic reticulum that would impair specific neurobiological pathways. Aiming to determine whether one or both of these potential mechanisms are implicated in DYT1 pathogenesis, we completed unbiased transcriptional and proteomic profiling in well-characterized neural cell lines that inducibly express wild-type or mutant torsinA. These experiments demonstrated that the accumulation of mutant torsinA in the nuclear envelope is not sufficient to cause transcriptional dysregulation. However, we detected expression changes at the protein level that, together with other reports, suggest a potential implication of torsinA on energy metabolism and regulation of the redox state. Furthermore, several proteins identified in this study have been previously linked to other forms of dystonia. In conclusion, our results argue against the hypothesis of transcriptional dysregulation in DYT1 dystonia, suggesting potential alternative pathogenic pathways.