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Objective: To verify the accuracy of totally implanted ports, tunnelled central venous catheters (CVC), widely used in cancer patients, and multi-lumen catheters, used in intensive care units (ICUs), in measuring central venous pressure (CVP), using right atrial pressure (RAP) measured in a Swan-Ganz catheter as the reference standard.Design: A prospective study, over a 10-month period.Setting: A medical-surgical ICU in a comprehensive cancer centre.Patients and Participants: Patients who had both (1) a Swan-Ganz catheter and (2) either a tunnelled catheter, a single or a multi-lumen catheter, or a totally implanted port.Interventions: RAP and CVP were measured simultaneously in each patient.Measurements and Results: Fifty-six pairs of RAP-CVP measurements were performed in 35 patients: 6 tunnelled catheters, 6 non-tunnelled single-lumen catheters, 26 multiple-lumen catheters and 18 totally implanted ports were studied. RAP measured in the Swan-Ganz catheter and CVP measured in the CVC were strongly correlated (r = 0.94, p < 0.01), whatever the type of catheter studied. The mean difference between RAP and CVP was -0.39 +/- 1.73 (SD) mmHg. In 51 cases (91%), the difference was within the limits of agreement (-3.78 to 3.00 mmHg, Bland and Altman method). For the five cases with a difference of 4 mmHg (three totally implanted ports, one double- and one triple-lumen catheter), CVP was greater than RAP.Conclusions: CVP can be accurately measured in totally implanted ports, tunnelled or non-tunnelled single-lumen and multiple-lumen catheters. When the difference exceeds the limit of agreement, the discrepancy between the two measurements has limited significance in most cases. [ABSTRACT FROM AUTHOR]

Background: A method of diagnosing catheter-related infection (CRI) without removing the catheter would be useful. An earlier positivity of central compared with peripheral venous-blood cultures may be associated with catheter-related bacteraemia. We evaluated prospectively the differential time to positivity (DTP) of paired blood cultures drawn simultaneously via the catheter hub and from a peripheral venous site.Methods: Over a 14-month period in an intensive-care unit of a cancer referral centre, simultaneous hub-blood and peripheral-blood cultures (a mean of two per patient) were obtained from patients with a suspected CRI. According to clinical criteria and quantitative culture of the catheter tip, cases were classified as CRI or sepsis of other origin. At least one pair of hub-blood and peripheral-blood cultures was obtained within 48 h before catheter removal, and we recorded the DTP between hub-blood and peripheral-blood cultures with an automatic device for detection of blood culture positivity.Findings: We analysed 93 catheters removed because of suspicion of CRI. In 28 episodes, the same micro-organisms were found in both hub-blood and peripheral-blood cultures. A diagnosis of definite bacteraemic CRI was made in 16 of the 17 patients in whom a positive hub-blood culture was detected at least 2 hours earlier than peripheral-blood culture. About half (9/17) of these episodes occurred in long-term (>30 days) devices. CRI was excluded in ten of the 11 patients with a DTP lower than 2 h. The DTP of paired blood cultures was significantly greater in patients with CRI than in others (p<10(-4)). A cut-off DTP value of 120 min had 91% specificity and 94% sensitivity for the diagnosis of CRI. Three of 17 episodes with only hub-blood culture positive were associated with CRI.Interpretation: This prospective study suggests that measurement of the differential time to positivity between hub-blood and peripheral-blood cultures is a simple and reliable tool for in-situ diagnosis of catheter-related sepsis in cancer patients. Further studies are needed to confirm these data for short-term catheters. [ABSTRACT FROM AUTHOR]

Hydrogels are natural/synthetic polymer-based materials with a large percentage of water content, usually above 80 %, and are suitable for many application fields such as wearable sensors, biomedicine, cosmetics, agriculture, etc. However, their performance is susceptible to environmental changes in temperature, relative humidity, and mechanical deformation due to their aqueous and soft nature. We investigate the mechanical response of both filled and unfilled alginate/gellan hydrogels using a combined axial-torsional rheometric approach with cylindrical samples of large length/diameter ratio under controlled temperature and relative humidity. Dynamic Mechanical Analysis (DMA) is performed on the same specimen in both torsion and extension under identical experimental conditions. This rheometric approach ensures consistent initial and boundary conditions, which are essential for a reliable estimation of viscoelastic moduli G* and E*, and their dependence on temperature, frequency, and relative humidity. Our findings indicate that humidity critically affects the mechanical response of the material due to sample volume shrinkage, necessitating corrections to the viscoelastic moduli. We also find temperature plays a role only at low/medium relative humidity values. The inclusion of fillers leads to a modest increase in the elasticity of the hydrogel, probably due to restricted water diffusion out of the sample. In connection with the latest, unfilled samples in breaking tests present only slippage due to twist-induced surface water excess, opposite to breakage events shown by filled samples, probably linked to restricted water diffusion., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: There is no conflict of interest to report. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Purpose: The purpose of this study was to assess the effect of training with a personal, portable laparoscopic endo-trainer (PLET) on residents' laparoscopic skills., Methods: The study took place at a tertiary-care academic university hospital in Switzerland. All participants were randomized to either a home- or hospital-based PLET training group, and surgical skill performance was assessed using five laparoscopic exercises. 24 surgical residents, 13 females and 11 males, were enrolled at any training stage. Nine residents completed the assessments. Endpoints consisted of subjective and objective assessment ratings as well as exercise time and qualitative data up to 12 weeks. The primary outcome was the difference in exercise time and secondary outcomes included performance scores as well as qualitative data., Results: The hospital-based training group performed exercises number 1, 3 and 4 faster at 12 weeks than at baseline (p = .003, < 0.001 and 0.024). Surgical skill performance was not statistically significantly different in any of the endpoints between the hospital- and home-based training groups at 12 weeks. Both the subjective and objective assessment ratings significantly improved in the hospital-based training group between baseline and 12 weeks (p = .006 and 0.003, respectively). There was no statistically significant improvement in exercise time as well as subjective and objective assessment ratings over time in the home-based training group. The qualitative data suggested that participants who were randomized to the hospital-based training group wished to have the PLET at home and vice versa. Several participants across groups lacked motivation because of their workload or time constraints, though most believed the COVID-19 pandemic had no influence on their motivation or the time they had for training., Conclusion: The PLET enhances laparoscopic surgical skills over time in a hospital-based training setting. In order to understand and optimize motivational factors, further research is needed., Trial Registration: This trial was retrospectively registered on clinicaltrials.gov (NCT06301230)., (© 2024. The Author(s).)

Purpose: Due to improved survival of esophageal cancer patients, long-term quality of life (QoL) is increasingly gaining importance. The aim of this study is to compare QoL outcomes between open Ivor Lewis esophagectomy (Open-E) and a hybrid approach including laparotomy and a robot-assisted thoracic phase (hRob-E). Additionally, a standard group of healthy individuals serves as reference., Methods: With a median follow-up of 36 months after hRob-E (n = 28) and 40 months after Open-E (n = 43), patients' QoL was assessed using the European Organization for Research and Treatment of Cancer (EORTC) QoL Questionnaire Core 30 (QLQ-C30) and the EORTC Esophagus specific QoL questionnaire 18 (QLQ-OES18)., Results: Patients showed similar clinical-pathological characteristics, but hRob-E patients had significantly higher ASA scores at surgery (p < 0.001). Patients and healthy controls reported similar global health status and emotional and cognitive functions. However, physical functioning of Open-E patients was significantly reduced compared to healthy controls (p = 0.019). Operated patients reported reduced role and social functioning, fatigue, nausea and vomiting, dyspnea, and diarrhea. A trend towards a better pain score after hRob-E compared to Open-E emerged (p = 0.063). Regarding QLQ-OES18, hRob-E- and Open-E-treated patients similarly reported eating problems, reflux, and troubles swallowing saliva., Conclusions: The global health status is not impaired after esophagectomy. Despite higher ASA scores, QoL of hRob-E patients is similar to that of patients operated with Open-E. Moreover, patients after hRob-E appear to have a better score regarding physical functioning and a better pain profile than patients after Open-E, indicating a benefit of minimally invasive surgery., (© 2024. The Author(s).)

Problem: Failure is a powerful teacher but an emotionally stressful experience. Before residency, when failure in clinical training is inevitable, medical students should learn to talk about and cope with failure. However, medical school curricula rarely include this topic, and physicians seldom share their mistakes and failures with trainees. This report describes and evaluates a workshop on dealing with failure in medicine., Approach: Two attending surgical consultants and a life coach facilitated the workshop between February 2021 and February 2022, which consisted of different educational approaches, such as presentations, small group discussions, and journal clubs. The sessions aimed to enable medical learners to identify and analyze actual and potential failure events in everyday clinical practice and learn from them, disclose and communicate medical failures and "speak up," reflect on failure and develop coping strategies, and understand the moderating role of fear of failure., Outcomes: Thirty medical students participated in the workshop. Dealing with failure in a productive manner was the medical learners' key learning objective and anticipated takeaway from the workshop. After the workshop, 19 of the 30 participants anonymously completed the standard university evaluation form. The medical students gave the workshop a mean (SD) rating of 8.59 (0.98) on a Likert scale ranging from 1 to 10. They felt better prepared to approach future challenges in a constructive manner after being equipped with strategies to deal with failure. Listening to the failure experiences of faculty and peers in a safe environment helped them accept that failure is inevitable., Next Steps: The findings suggest that medical students appreciated a safe environment to discuss failure. By promoting a safe learning environment early in the medical career, medical schools could make an important contribution to reducing the stigma of failure and eliminating the shame and blame culture, thus contributing to students' well-being., (Copyright © 2023 the Association of American Medical Colleges.)

The study reports on a simple system to fabricate skin substitutes consisting of a naturally occurring bacterial polysaccharide gellan gum. Gelation was driven by the addition of a culture medium whose cations induced gellan gum crosslinking at physiological temperature, resulting in hydrogels. Human dermal fibroblasts were incorporated in these hydrogels and their mechanical, morphological, and penetration characteristics were studied. The mechanical properties were determined by means of oscillatory shear rheology, and a short linear viscoelastic regime was noted up to less than 1% of strain amplitude. The storage modulus increased with an increasing polymer concentration. The moduli were in the range noted for native human skin. After 2 weeks of fibroblast cultivation, the storage moduli showed signs of deterioration, so that a culture time of 2 weeks was proposed for further studies. Microscopic and fluorescent staining observations were documented. These depicted a crosslinked network structure in the hydrogels with a homogeneous distribution of cells and an assured cell viability of 2 weeks. H&E staining was also performed, which showed some traces of ECM formation in a few sections. Finally, caffeine penetration experiments were carried out with Franz diffusion cells. The hydrogels with a higher concentration of polymer containing cells showed an improved barrier function against caffeine compared to previously studied multicomponent hydrogels as well as commercially available 3D skin models. Therefore, these hydrogels displayed both mechanical and penetration compatibility with the ex vivo native human skin., (© 2023 The Authors. Journal of Biomedical Materials Research Part A published by Wiley Periodicals LLC.)

Objective: The aim of the present study was three-fold. One, to assess the prevalence of medical traumatization in outpatients of a gynecologic department; two, to analyze the relationship of medical traumatization with adverse childhood events; and three, to investigate the extent to which medical traumatization affects the health outcomes of woman., Methods: Between January and September 2022, a prospective cross-sectional study recruited patients of a gynecologic outpatient clinic at St. Gallen Cantonal Hospital in Switzerland. Medical trauma was a self-reported item. The presence of adverse childhood events was assessed using the Childhood Trauma Questionnaire. The severity of post-traumatic stress was evaluated using the Impact of Event Scale Revised questionnaire., Results: In total, 227 patients were recruited. Medical trauma was reported by 20% of the interviewees and it was strongly associated with obesity (A = 0.005). Undergoing surgery was most commonly the source of psychological distress (5.7%) followed by delivery (4.8%), pregnancy loss (4.8%), and cancer diagnosis (4.0%). Yet, fewer than 1% of the patients reached the threshold suggesting post-traumatic stress disorder., Conclusions: We found no relationship between the medical trauma, adverse childhood events, cardiovascular disease, or substance abuse. The presence of medical trauma was associated with the patient's body mass index (calculated as weight in kilograms divided by the square of height in meters)., (© 2023 International Federation of Gynecology and Obstetrics.)

Biobased and biodegradable films were prepared by physically mixing 2,3-dialdehyde cellulose (DAC) with two other biopolymers, zein and gelatin, in three different proportions. The antimicrobial activities of the composite blends against Gram-positive and Gram-negative bacteria increase with the increase of DAC content. Cell viability tests on mammalian cells showed that the materials were not cytotoxic. In addition, DAC and gelatin were able to promote thermal degradation of the blends. However, DAC increased the stiffness and decreased the glass transition temperature of the blends, while gelatin was able to decrease the stiffness of the film. Morphological analysis showed the effect of DAC on the surface smoothness of the blends. The contact angle confirmed that all blends were within the range of hydrophilic materials. Although all the blends showed impressive performance for wound dressing application, the blend with gelatin might be more suitable for this purpose due to its better mechanical performance and antibacterial activity., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

We report a custom-made technique to synthesize process-convenient skin scaffolds by tuning the mechanical properties of hydrogels based on a few naturally occurring polysaccharides to match the rheological properties of previously established benchmarks, i.e., the ex vivo native human skins. We studied the mechanical parameters using oscillatory shear rheology. At small strain amplitudes, the intrinsic elastic modulus showed an almost linear dependence in the middle and a changing rate profile at the two ends with concentration of the principal hydrogel component variant, i.e., kappa (κ)-carrageenan. At large strain amplitudes, the hydrogels demonstrated intercycle strain-softening behavior, the onset of which was directly proportional to the κ-carrageenan concentration. We observed a concentration match for the intrinsic elastic modulus of the benchmark within this sigmoidal curve fit. Contextually, we need to explore other potent polymeric hydrogel systems to achieve mechanical affinity in terms of multiple rheological parameters derived from both strain amplitude and angular frequency sweeps. Additionally, we carried out diffusion experiments to study caffeine permeation attributes. The hydrogels show improved barrier features with increasing κ-carrageenan concentration. In terms of the penetration flux and total cumulative amount of permeated caffeine, this enhanced mechanical adherence demonstrates comparable penetration features with the commercial 3D skin model., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

There is a growing interest in the in situ gelation of the alginate-Ca 2+ system due to its remarkable applications. In this work, we record and evaluate the fast gelation kinetics of alginate-Ca 2+ using a custom-made rheometric setup. This enables us to inject CaCl 2 into the alginate while we perform the rheological measurements. We successfully measure the in situ gelation reaction from the early stages. As the alginate concentration is increased up to 3 wt.%, we observe a systematic increase of the elastic modulus, G'. Similarly, higher concentrations and injected volumes of CaCl 2 increase the magnitude and initial growth rate of G'. At longer times, the growth rate of G' is lower. It decreases further very slowly, indicating that the chemical reaction requires quite a considerable amount of time to be completed. Finally, from the rheometric data, we estimate the average rates of the elastic modulus during the initial and quasi-steady-state stages., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Hypothesis: Previously, we examined the impact of two preparation procedures on the mechanical properties of native gelatin gels. In this work, we extend our research by considering hard spherical particles as fillers. We expect that the presence of these fillers significantly affects the viscoelastic response., Experiments: We prepared fresh in situ gels and individual gel layers filled with glass micro-beads up to 1% w/w and aged for 24 and 48 h. The hydrogels were made of 3 and 5% w/w gelatin at 5 °C, and we performed large amplitude oscillatory shear (LAOS) tests. We analyzed the intracycle linear and nonlinear response using normalized Lissajous-Bowditch curves. Utilizing the MITlaos software, we decomposed the total intracycle stress into elastic and viscous contributions and calculated the Chebyshev harmonics coefficients., Findings: The fresh in situ gels exhibit severe progressive stiffening during the strain sweeps and a subsequent sharp decrease of both moduli. The filled layers show smoother yielding than the in situ gels. The fillers increase the dynamic moduli, affect the terminal LAOS regime, and enhance the intracycle nonlinearities at higher concentrations. The Lissajous-Bowditch curves of the aged layers indicate elastoplastic behavior, which is more pronounced for the 48 h filled gel layer than the native counterpart., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The gelation procedure and the gelation time of gelatin gels may lead to apparently similar materials, however, with different rheological fingerprints under small and large oscillatory shear deformations. Here, in the first paper of this series, gelation of 3 and 5% w/w gelatin solutions at 5 °C was performed in situ on the rheometer plate and in custom-made casting modules to obtain individual gel layers. Large amplitude oscillatory shear (LAOS) tests were performed. The nonlinear deformation regime was qualitatively analyzed using normalized Lissajous-Bowditch curves. The MITlaos software was employed to decompose the total intracycle stress response and to calculate the Chebyshev coefficients ratios. The dynamic moduli of the fresh gels were measured directly after the in situ preparation and within a time frame until 1.5 h. In the strain sweeps, we observed intense stiffening followed by yielding above 200% strain. However, the individual gel layers aged for 24 and 48 h show different LAOS fingerprints. The extensive loops in the viscous Lissajous-Bowditch curves indicate an elastoplastic material response. Based on the overall nonlinear rheological response, we propose a structural formation that describes the behavior of the gels for the conditions studied here. In the second paper of this series, we give the impact of hard micro-fillers (glass beads) and we describe the nonlinear characteristics of the filled gels., (Copyright © 2019 Elsevier Inc. All rights reserved.)

This work discusses the first set of rheometric measurements carried out on commercially accessible juvenile and aged skin models under large amplitude oscillatory shear deformations. The results were compared with those of native male whole human and dermis-only foreskin specimens, catering to a few ages from 0.5 to 68 years, including specimens from a 23-year-old male abdomen. At large strains, strain thinning was more pronounced for the dermis of the young skins and for their whole skin counterparts. An inverse qualitative tendency was observed for the adult skins and the skin models. This can be explained by the high dermal collagen compactness associated with an incomplete epidermal proliferation. The qualitative Lissajous plots as well as the quantitative dimensionless indices analyzed using the MITlaos software indicated predominant nonlinear intracycle elastic strain stiffening and viscous shear thinning for all the native specimens at the maximum deformation. For the full thickness models, we have evidence of structure collapse and yielding under similar conditions. The whole skin specimen from the 68-year-old male showed smaller age-dependent nonlinear elastic contributions than the dermis, which we relate to the epidermal degeneration taking place during aging. Regardless of the age group, the models manifested more pronounced intercycle and intracycle elastic nonlinearities, and their magnitudes were significantly larger. The nonlinear elastic trends will serve as advanced standards for understanding and delineating the mechanical limits of destructive and non-destructive deformations of such unique biomaterials., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

It is essential for microbes to acquire information about their environment. Fungi use soluble degradation products of plant cell wall components to understand the substrate composition they grow on. Individual perception pathways have been well described. However, the interconnections between pathways remain poorly understood. In the present work, we provide evidence of crosstalk between the perception pathways for cellulose and the hemicellulose mannan being conserved in several filamentous fungi and leading to the inhibition of cellulase expression. We used the functional genomics tools available for Neurospora crassa to investigate this overlap at the molecular level. Crosstalk and competitive inhibition could be identified both during uptake by cellodextrin transporters and intracellularly. Importantly, the overlap is independent of CRE-1-mediated catabolite repression. These results provide novel insights into the regulatory networks of lignocellulolytic fungi and will contribute to the rational optimization of fungal enzyme production for efficient plant biomass depolymerization and utilization. IMPORTANCE In fungi, the production of enzymes for polysaccharide degradation is controlled by complex signaling networks. Previously, these networks were studied in response to simple sugars or single polysaccharides. Here, we tackled for the first time the molecular interplay between two seemingly unrelated perception pathways: those for cellulose and the hemicellulose (gluco)mannan. We identified a so far unknown competitive inhibition between the respective degradation products acting as signaling molecules. Competition was detected both at the level of the uptake and intracellularly, upstream of the main transcriptional regulator CLR-2. Our findings provide novel insights into the molecular communication between perception pathways. Also, they present possible targets for the improvement of industrial strains for higher cellulase production through the engineering of mannan insensitivity., (Copyright © 2019 Hassan et al.)