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Antibiotics that use novel mechanisms are needed to combat antimicrobial resistance1-3. Teixobactin4 represents a new class of antibiotics with a unique chemical scaffold and lack of detectable resistance. Teixobactin targets lipid II, a precursor of peptidoglycan5. Here we unravel the mechanism of teixobactin at the atomic level using a combination of solid-state NMR, microscopy, in vivo assays and molecular dynamics simulations. The unique enduracididine C-terminal headgroup of teixobactin specifically binds to the pyrophosphate-sugar moiety of lipid II, whereas the N terminus coordinates the pyrophosphate of another lipid II molecule. This configuration favours the formation of a β-sheet of teixobactins bound to the target, creating a supramolecular fibrillar structure. Specific binding to the conserved pyrophosphate-sugar moiety accounts for the lack of resistance to teixobactin4. The supramolecular structure compromises membrane integrity. Atomic force microscopy and molecular dynamics simulations show that the supramolecular structure displaces phospholipids, thinning the membrane. The long hydrophobic tails of lipid II concentrated within the supramolecular structure apparently contribute to membrane disruption. Teixobactin hijacks lipid II to help destroy the membrane. Known membrane-acting antibiotics also damage human cells, producing undesirable side effects. Teixobactin damages only membranes that contain lipid II, which is absent in eukaryotes, elegantly resolving the toxicity problem. The two-pronged action against cell wall synthesis and cytoplasmic membrane produces a highly effective compound targeting the bacterial cell envelope. Structural knowledge of the mechanism of teixobactin will enable the rational design of improved drug candidates.

ABSTRACT Background Colorectal cancer is identified as a lifestyle‐related type of cancer. There is an increasing emphasis on lifestyle interventions targeting pivotal lifestyle factors such as excess weight, cigarette smoking, alcohol consumption, poor diet and physical inactivity as primary and tertiary prevention. Furthermore, modifying these lifestyle factors has the potential to improve quality of life for cancer patients. We aim to identify, appraise and synthesise the available evidence regarding the effect of combined lifestyle interventions on quality of life in colorectal cancer survivors. Methods Pubmed, Ovid Embase and the Cochrane Library were searched for studies reporting on quality of life in post‐treatment colorectal cancer patients. The systematic literature search was performed according to the Preferred Reporting Items for systematic reviews and meta‐analysis (PRISMA) guidelines. Results Five articles reporting on 719 individual patients were included. Two studies reported significantly better results in (cancer‐specific) quality‐of‐life questionnaires for patients after combined lifestyle interventions. Conclusion We conclude that there is some evidence that combined lifestyle interventions could have beneficial effects on the quality of life of colorectal cancer survivors. Future randomised controlled trials reporting on quality of life of combined lifestyle interventions in colorectal cancer survivors are warranted.

Physical properties of biological membranes directly or indirectly govern biological processes. Yet, the interplay between membrane and integral membrane proteins is difficult to assess due to reciprocal effects between membrane proteins, individual lipids, and membrane architecture. Using solid-state NMR (SSNMR) we previously showed that KirBac1.1, a bacterial Inward-Rectifier K+ channel, nucleates bilayer ordering and microdomain formation through tethering anionic lipids. Conversely, these lipids cooperatively bind cationic residues to activate the channel and initiate K+ flux. The mechanistic details governing the relationship between cooperative lipid loading and bilayer ordering are, however, unknown. To investigate, we generated KirBac1.1 samples with different concentrations of 13C-lableded phosphatidyl glycerol (PG) lipids and acquired a full suite of SSNMR 1D temperature series experiments using the ordered all-trans (AT) and disordered trans-gauche (TG) acyl conformations as markers of bilayer dynamics. We observed increased AT ordered signal, decreased TG disordered signal, and increased bilayer melting temperature with increased PG concentration. Further, we identified cooperativity between ordering and direct binding of PG lipids, indicating KirBac1.1-driven bilayer ordering and microdomain formation is a classically cooperative Hill-type process driven by and predicated upon direct binding of PG lipids. Our results provide unique mechanistic insight into how proteins and lipids in tandem contribute to supramolecular bilayer heterogeneity in the lipid membrane.

Objective:. In this review, we aim to provide an overview of literature on lymph node (LN) histomorphological features and their relationship with the prognosis in colorectal cancer (CRC). Background:. Lymph nodes play a crucial role in the treatment and prognosis of CRC. The presence of LN metastases considerably worsens the prognosis in CRC patients. Literature has shown that the total number of LNs and the number negative LNs (LNnegs) has prognostic value in CRC patients. In esophageal carcinoma, LN size seems to be surrogate of the host antitumor response and a potentially clinically useful new prognostic biomarker for (y)pN0 esophageal carcinoma. Methods:. A comprehensive search was performed in Pubmed, Embase, Medline, CINAHL, and the Cochrane library in March 2021. The PRISMA guidelines were followed. Only studies focusing on histomorphological features and LN size and their relation to overall survival were selected. Results:. A total of 9 unique articles met all inclusion criteria and were therefore included in this systematic review. Six of these studies investigated HMF (eg, paracortical hyperplasia, germinal center predominance, and sinus histiocytosis) and 4 studies LNneg size and their relationship with overall survival. The presence of paracortical hyperplasia and an increased number of large LNnegs is related to a more favorable prognosis in CRC. Conclusion:. The results of this systematic review seem to support the hypothesis that there is a relationship between the host antitumor response reflected in different histomorphological reaction patterns visible in LNnegs and LNneg size related to survival in CRC patients.

Background: Growing evidence on the use of mesh as a prophylactic measure to prevent parastomal hernia and advances in guideline development methods prompted an update of a previous guideline on parastomal hernia prevention.Objective: To develop evidence-based, trustworthy recommendations, informed by an interdisciplinary panel of stakeholders.Methods: We updated a previous systematic review on the use of a prophylactic mesh for end colostomy, and we synthesized evidence using pairwise meta-analysis. A European panel of surgeons, stoma care nurses, and patients developed an evidence-to-decision framework in line with GRADE and Guidelines International Network standards, moderated by a certified guideline methodologist. The framework considered benefits and harms, the certainty of the evidence, patients’ preferences and values, cost and resources considerations, acceptability, equity and feasibility.Results: The certainty of the evidence was moderate for parastomal hernia and low for major morbidity, surgery for parastomal hernia, and quality of life. There was unanimous consensus among panel members for a conditional recommendation for the use of a prophylactic mesh in patients with an end colostomy and fair life expectancy, and a strong recommendation for the use of a prophylactic mesh in patients at high risk to develop a parastomal hernia.Conclusion: This rapid guideline provides evidence-informed, interdisciplinary recommendations on the use of prophylactic mesh in patients with an end colostomy. Further, it identifies research gaps, and discusses implications for stakeholders, including overcoming barriers to implementation and specific considerations regarding validity.

Objective: To perform a systematic review and meta-analysis on the effectiveness of prophylactic mesh for the prevention of parastomal hernia in end colostomy, with the ultimate objective to summarize the evidence for an interdisciplinary, European rapid guideline.Methods: We updated a previous systematic review with de novo evidence search of PubMed from inception up to June 2022. Primary outcome was quality of life (QoL). Secondary outcomes were clinical diagnosis of parastomal hernia, surgery for parastomal hernia, and 30 day or in-hospital complications Clavien-Dindo ≥3. We utilised the revised Cochrane Tool for randomised trials (RoB 2 tool) for risk of bias assessment in the included studies. Minimally important differences were set a priori through voting of the panel members. We appraised the evidence using GRADE and we developed GRADE evidence tables.Results: We included 12 randomized trials. Meta-analysis suggested no difference in QoL between prophylactic mesh and no mesh for primary stoma construction (SMD = 0.03, 95% CI [−0.14 to 0.2], I2 = 0%, low certainty of evidence). With regard to parastomal hernia, the use of prophylactic synthetic mesh resulted in a significant risk reduction of the incidence of the event, according to data from all available randomized trials, irrespective of the follow-up period (OR = 0.33, 95% CI [0.18–0.62], I2 = 74%, moderate certainty of evidence). Sensitivity analyses according to follow-up period were in line with the primary analysis. Little to no difference in surgery for parastomal hernia was encountered after pooled analysis of 10 randomised trials (OR = 0.52, 95% CI [0.25–1.09], I2 = 14%). Finally, no significant difference was found in Clavien-Dindo grade 3 and 4 adverse events after surgery with or without the use of a prophylactic mesh (OR = 0.77, 95% CI [0.45–1.30], I2 = 0%, low certainty of evidence).Conclusion: Prophylactic synthetic mesh placement at the time of permanent end colostomy construction is likely associated with a reduced risk for parastomal hernia and may confer similar risk of peri-operative major morbidity compared to no mesh placement. There may be no difference in quality of life and surgical repair of parastomal hernia with the use of either approach.

Objectives Vaginal balloon inflation simulates the compressive forces on the pelvic floor during the second phase of natural delivery. The foremost use of this animal model of vaginal distention (VD) is to study the mechanisms underlying urinary incontinence. As damage to the pelvic floor during natural birth is a common cause of fecal incontinence, the present paper aimed to investigate the effect of VD on defecation behavior in adult rats. Methods Vaginal distention was performed in 8 rats for 2 hours, and in 3 rats for 4 hours, and sham inflation was performed in 4 rats. With the use of a latrine box in the rat home-cage and 24/7 video tracking, the defecation behavior was examined. The time spent in and outside the latrine was monitored for two weeks preoperatively and three weeks postoperatively, and a defecation behavior index (DBI; range: 0 [continent] to 1 [incontinent]) was defined. Pelvic floor tissue was collected postmortem and stained with hematoxylin and eosin. Results Vaginal balloon inflation for 2 hours resulted in fecal incontinence in 29% of the animals (responders) whereas the DBI scores of non-responders (71%) and control animals did not change in the postoperative phase compared with the baseline score. A 4-hour balloon inflation resulted in fecal incontinence in 1 animal and caused a humane endpoint in 2 animals with markedly more tissue damage in the 4-hour responder compared with the 2-hour responders. Conclusions Vaginal balloon inflation, with an optimum duration between 2 and 4 hours, can be used as a model to study changes in defecation behavior in rats induced by pelvic floor damage.

Objective Until today, the true pathophysiology of hemorrhoidal disease (HD) has not yet been unraveled. More and more evidence guides us towards the hypothesis that reduced connective tissue stability is associated with a higher incidence of hemorrhoids. The present study aimed to compare the quantity and quality of collagen, and vessel morphometrics, in patients with symptomatic HD compared with normal controls. Methods Twenty-two samples of grade III and grade IV HD tissue from patients undergoing a hemorrhoidectomy between January 2004 and June 2015 were included in the study group. Samples of 15 individuals without symptomatic HD who donated their body to science and died a natural death served as controls. The quantity and quality of anal collagen, and anal vessel morphometrics were objectified. The quality of collagen was subdivided in young (immature) and old (mature) collagen. Results Patients with HD had an increased percentage of total anal collagen (62.1 ± 13.8 versus 18.7 ± 14.5%; p = 0.0001), a decreased percentage of young collagen (0.00009 ± 0.00008 versus 0.0008 ± 0.0008%; p = 0.001), and a smaller surface area of the anal vessels (795.1 ± 1215.9 micrometre2 versus 1219.0 ± 1976.1; p = 0.003) compared with controls. The percentage of old collagen did not differ between the control and study groups (0.588 ± 0.286% versus 0.389 ± 0.242%; p = 0.06). Conclusion The outcomes of the present study suggest that alterations in anal collagen composition may play a role in the formation of hemorrhoids.

Aim: In the last decade, the Netherlands has implemented various diagnostic and treatment strategies to enhance rectal cancer outcomes. This study, using data from the Prospective Dutch ColoRectal Cancer (PLCRC) cohort, investigates whether these multidisciplinary advancements have translated into improved health‐related quality of life (HRQoL) and functional outcomes for the general Dutch rectal cancer population. Methods: Patients with Stage I–III rectal cancer enrolled in the PLCRC cohort were included. HRQoL and functional outcomes were assessed 1 and 2 years after diagnosis using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ‐C30), EORTC QLQ Colorectal Cancer 29 and the Low Anterior Resection Syndrome score. HRQoL and functional outcomes were compared based on year of diagnosis (2014–2019). Results: A total of 1294 patients were included. Two years after diagnosis, patients diagnosed in 2019 (n = 392) had a clinically relevant higher score on physical (8.2, 95% CI 4.1–12.3), role (13.5, 95% CI 7.3–19.7) and social functioning (5.8, 95% CI 0.3–11.2) compared to those diagnosed in 2014 (n = 65). Additionally, patients diagnosed in 2019 experienced less fatigue 2 years after diagnosis compared to those diagnosed in 2014 (−8.6, 95% CI −14.1 to −3.0). The Low Anterior Resection Syndrome score showed no differences. Conclusion: The findings of this study suggest that over the past decade rectal cancer patients in the Netherlands have witnessed improvements in HRQoL across various domains. Most probably, the improvement is due to a combination of implementation of population screening, a more restrictive neoadjuvant radiotherapy policy and advances in minimally invasive surgery and organ preserving treatment options. [ABSTRACT FROM AUTHOR]

Background The impact of COVID-19 in healthcare systems globally was unprecedented leading to cancelations of most planned surgical activities. Surgical trainees were redeployed to Intensive Care and Emergency units supporting urgent and unplanned care on COVID-19 patients. Theater exposure, crucial part of surgical training, was reduced to minimal since elective cases were postponed, and emergency operating was carried out by consultants only. Surgical research has also been severely hit with most of the clinical trials been postponed. Teaching activities as well as national and international congresses and surgical courses important tools for continuous professional development were canceled. Methods The primary aim of our study was to summarize the changes in surgical training during the pandemic. This was followed by a review of the existing social media platforms, video-conferencing platforms along with the role of the social media in surgical training. The crucial role of simulation in surgical training was explored and alternative ways of training with engagement of the feedback mechanisms were proposed. The secondary aim was to highlight possible novel educational strategies for the forthcoming post-COVID-19 era. Conclusions The “new” era forced the educational boards to reexamine training curriculums. Innovation strategies and cooperation on the part of surgical residency programs is crucial. Strong leadership is needed, on the part of the education bodies with restructuring of the surgical programmes to accommodate alternative ways of training is necessary to maintain rigorous standards of education and training.