Search

Therapeutics to combat multidrug-resistant bacteria such as Klebsiella pneumoniae are needed. Here the authors show immune evasion drives lipopolysaccharide O2 serotype expansion in multidrug-resistant isolates, and anti-O-antigen human monoclonal antibodies synergize with antibiotics to protect mice from infection.

Background: Awareness of the potential global overtreatment of patients with appendiceal neuroendocrine tumours (NETs) of 1-2 cm in size by performing oncological resections is increasing, but the rarity of this tumour has impeded clear recommendations to date. We aimed to assess the malignant potential of appendiceal NETs of 1-2 cm in size in patients with or without right-sided hemicolectomy., Methods: In this retrospective cohort study, we pooled data from 40 hospitals in 15 European countries for patients of any age and Eastern Cooperative Oncology Group performance status with a histopathologically confirmed appendiceal NET of 1-2 cm in size who had a complete resection of the primary tumour between Jan 1, 2000, and Dec 31, 2010. Patients either had an appendectomy only or an appendectomy with oncological right-sided hemicolectomy or ileocecal resection. Predefined primary outcomes were the frequency of distant metastases and tumour-related mortality. Secondary outcomes included the frequency of regional lymph node metastases, the association between regional lymph node metastases and histopathological risk factors, and overall survival with or without right-sided hemicolectomy. Cox proportional hazards regression was used to estimate the relative all-cause mortality hazard associated with right-sided hemicolectomy compared with appendectomy alone. This study is registered with ClinicalTrials.gov, NCT03852693., Findings: 282 patients with suspected appendiceal tumours were identified, of whom 278 with an appendiceal NET of 1-2 cm in size were included. 163 (59%) had an appendectomy and 115 (41%) had a right-sided hemicolectomy, 110 (40%) were men, 168 (60%) were women, and mean age at initial surgery was 36·0 years (SD 18·2). Median follow-up was 13·0 years (IQR 11·0-15·6). After centralised histopathological review, appendiceal NETs were classified as a possible or probable primary tumour in two (1%) of 278 patients with distant peritoneal metastases and in two (1%) 278 patients with distant metastases in the liver. All metastases were diagnosed synchronously with no tumour-related deaths during follow-up. Regional lymph node metastases were found in 22 (20%) of 112 patients with right-sided hemicolectomy with available data. On the basis of histopathological risk factors, we estimated that 12·8% (95% CI 6·5 -21·1) of patients undergoing appendectomy probably had residual regional lymph node metastases. Overall survival was similar between patients with appendectomy and right-sided hemicolectomy (adjusted hazard ratio 0·88 [95% CI 0·36-2·17]; p=0·71)., Interpretation: This study provides evidence that right-sided hemicolectomy is not indicated after complete resection of an appendiceal NET of 1-2 cm in size by appendectomy, that regional lymph node metastases of appendiceal NETs are clinically irrelevant, and that an additional postoperative exclusion of metastases and histopathological evaluation of risk factors is not supported by the presented results. These findings should inform consensus best practice guidelines for this patient cohort., Funding: Swiss Cancer Research foundation., Competing Interests: Declaration of interests MBe reports funding from Novartis, Pfizer, and Ipsen; payment or honoraria for lectures, presentations, speaker bureaus, manuscript writing, or educational events from Novartis, Pfizer, Ipsen, and Advanced Accelerator Applications (AAA); support for attending meetings or travel from Novartis, Pfizer, and Ipsen; and participation on data safety monitoring board or advisory boards from Pfizer and AAA. IB reports payment or honoraria for lectures, presentations, speaker bureaus, manuscript writing, or educational events from Bristol Myers Squibb (BMS) and Bayer Vital and support for attending meetings or travel for European Musculo-Skeletal Oncology Society 2022 conference from PharmaMar. RG-C reports funding of investigator-initiated clinical trials from Pfizer, BMS, and MSD, and an real-world data project from Servier; consulting fees from AAA/Novartis, Advanz Pharma, Amgen, Bayer, BMS, Boehringer (Ingelheim), Esteve, Hutchmed, Ipsen, Merck, Midatech Pharma, MSD, PharmaMar, and Pierre Fabre; and payment or honoraria for lectures, presentations, speaker bureaus, manuscript writing, or educational events from Roche. GC reports grants or contracts from AAA; consulting fees from AAA; payments or honoraria for lectures, presentations, speaker bureaus, manuscript writing, or educational events from AAA, Ipsen, and Keocyt; and support for attending meetings or travel from AAA, Ipsen, and Keocyt. MPa reports payments for advisory boards or lectures from AAA and Novartis; payments for advisory boards, consultancy, or lectures from Ipsen; payment for lectures from Boehringer Ingelheim, MSD, Lilly, and Recordati; payment for advisory boards from Riemser; payment for services (radiological review of phase 3 study) from Hutchmed; payment for travel for participation in study steering committee meeting from Rayzebio; payment to institution from Crinetics and AAA; and unpaid roles as ENETS vice president, European Society for Medical Oncology (ESMO) Education Committee, ESMO scientific steering committee NET track, advisor on the International Neuroendocrine Cancer Alliance board, and advisor for German patient support group. GR reports payments for speaker bureaus from AAA. AR reports being an ENETS Advisory Board member. TV reports payment or honoraria for lectures, presentations, speaker bureaus, manuscript writing, or educational events from Ipsen; support for attending meetings or travel from Ipsen; and an unpaid position as secretary in the Dutch Belgian Neuroendocrine Tumor Society. All other authors declare no competing interests., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Thermoplastic polymer-filler composites are excellent materials for bone tissue engineering (TE) scaffolds, combining the functionality of fillers with suitable load-bearing ability, biodegradability, and additive manufacturing (AM) compatibility of the polymer. Two key determinants of their utility are their rheological behavior in the molten state, determining AM processability and their mechanical load-bearing properties. We report here the characterization of both these physical properties for four bone TE relevant composite formulations with poly(ethylene oxide terephthalate)/poly(butylene terephthalate (PEOT/PBT) as a base polymer, which is often used to fabricate TE scaffolds. The fillers used were reduced graphene oxide (rGO), hydroxyapatite (HA), gentamicin intercalated in zirconium phosphate (ZrP-GTM) and ciprofloxacin intercalated in MgAl layered double hydroxide (MgAl-CFX). The rheological assessment showed that generally the viscous behavior dominated the elastic behavior ( G ″ > G ') for the studied composites, at empirically determined extrusion temperatures. Coupled rheological-thermal characterization of ZrP-GTM and HA composites showed that the fillers increased the solidification temperatures of the polymer melts during cooling. Both these findings have implications for the required extrusion temperatures and bonding between layers. Mechanical tests showed that the fillers generally not only made the polymer stiffer but more brittle in proportion to the filler fractions. Furthermore, the elastic moduli of scaffolds did not directly correlate with the corresponding bulk material properties, implying composite-specific AM processing effects on the mechanical properties. Finally, we show computational models to predict multimaterial scaffold elastic moduli using measured single material scaffold and bulk moduli. The reported characterizations are essential for assessing the AM processability and ultimately the suitability of the manufactured scaffolds for the envisioned bone regeneration application., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Pseudomonas aeruginosa is a major cause of hospital-acquired infections, particularly in mechanically ventilated patients, and it is the leading cause of death in cystic fibrosis patients. A key virulence factor associated with disease severity is the P. aeruginosa type III secretion system (T3SS), which injects bacterial toxins directly into the cytoplasm of host cells. The PcrV protein, located at the tip of the T3SS injectisome complex, is required for T3SS function and is a well-validated target in animal models of immunoprophylactic strategies targeting P. aeruginosa. In an effort to identify a highly potent and protective monoclonal antibody (MAb) that inhibits the T3SS, we generated and characterized a panel of novel anti-PcrV MAbs. Interestingly, some MAbs exhibiting potent inhibition of T3SS in vitro failed to provide protection in a mouse model of P. aeruginosa infection, suggesting that effective in vivo inhibition of T3SS with anti-PcrV MAbs is epitope dependent. V2L2MD, while not the most potent MAb as assessed by in vitro cytotoxicity inhibition assays, provided strong prophylactic protection in several murine infection models and a postinfection therapeutic model. V2L2MD mediated significantly (P < 0.0001) better in vivo protection than that provided by a comparator antibody, MAb166, a well-characterized anti-PcrV MAb and the progenitor of a clinical candidate, KB001-A. The results described here support further development of a V2L2MD-containing immunotherapeutic and may suggest even greater potential than was previously recognized for the prevention and treatment of P. aeruginosa infections in high-risk populations., (Copyright © 2014, American Society for Microbiology. All Rights Reserved.)

This study examined the role of coping with social stressors in the development of depressive symptoms, as well as gender differences in this process. Participants included 978 adolescents (aged 14-18 years), who completed measures of social stressors, coping responses, and depressive symptoms at the beginning of the study and measures of depressive symptoms at a six-month follow-up. High levels of disengagement and low levels of secondary control coping predicted a residual increase in depressive symptoms at follow-up. Interactive effects were weak and moderated by gender: among female adolescents, the use of disengagement coping exacerbated the impact of social stressors on depressive symptoms, whereas the use of secondary control reduced these effects. Female adolescents scored higher than male adolescents on perceived social stress, disengagement, and primary control coping. Moreover, differences in perceived social stress and disengagement coping contributed to explain the female adolescents' higher scores on depressive symptoms. These findings have important implications for interventions.