Experience and Needs of Patients With Young-Onset Colorectal Cancer and Their Caregivers: A Qualitative Study.

PURPOSE: The incidence of young-onset colorectal cancer (YOCRC; defined as patients who are diagnosed with CRC before age 50 years) is rising rapidly, and CRC is predicted to be the leading cause of cancer death in this age group by 2030. Yet, there has been limited research into the experiences and needs of patients with YOCRC and their caregivers. The goal of this study was to better understand the experiences and needs of patients with YOCRC and their caregivers. PATIENTS AND METHODS: Semistructured focus groups were conducted with patients with YOCRC, caregivers of patients with YOCRC, and bereaved caregivers of patients with YOCRC. Focus group discussion guides addressed the experience and impact of diagnosis and treatment of YOCRC. Results were analyzed using a thematic analysis informed by framework analysis. RESULTS: Twenty patients and caregivers participated in three focus groups (eight patients, seven caregivers, and five bereaved caregivers). Four primary themes were identified: (1) feeling overwhelmed by the health care system and desiring patient navigation; (2) feeling isolated and wanting opportunities for peer support; (3) life disruption because of difficulty juggling multiple roles and desiring psychosocial support; and (4) enthusiasm about participation in research and genetic testing. CONCLUSION: This study identified and described the unique experiences and care needs of patients with YOCRC and their caregivers. The findings provide evidence that specialized models of care are needed. The results of this study informed the development of a center dedicated to the care of patients with YOCRC.

Optimization of Host Cell-Compatible, Antimicrobial Peptides Effective against Biofilms and Clinical Isolates of Drug-Resistant Bacteria.

Here, we describe the continued synthetic molecular evolution of a lineage of host-compatible antimicrobial peptides (AMP) intended for the treatment of wounds infected with drug-resistant, biofilm-forming bacteria. The peptides tested are variants of an evolved AMP called d-amino acid CONsensus with Glycine Absent (d-CONGA), which has excellent antimicrobial activities in vitro and in vivo. In this newest generation of rational d-CONGA variants, we tested multiple sequence-structure-function hypotheses that had not been tested in previous generations. Many of the peptide variants have lower antibacterial activity against Gram-positive or Gram-negative pathogens, especially variants that have altered hydrophobicity, secondary structure potential, or spatial distribution of charged and hydrophobic residues. Thus, d-CONGA is generally well tuned for antimicrobial activity. However, we identified a variant, d-CONGA-Q7, with a polar glutamine inserted into the middle of the sequence, that has higher activity against both planktonic and biofilm-forming bacteria as well as lower cytotoxicity against human fibroblasts. Against clinical isolates of Klebsiella pneumoniae, innate resistance to d-CONGA was surprisingly common despite a lack of inducible resistance in Pseudomonas aeruginosa reported previously. Yet, these same isolates were susceptible to d-CONGA-Q7. d-CONGA-Q7 is much less vulnerable to AMP resistance in Gram-negative bacteria than its predecessor. Consistent with the spirit of synthetic molecular evolution, d-CONGA-Q7 achieved a critical gain-of-function and has a significantly better activity profile.

Cancer Caregivers' Prognostic and End-of-Life Communication Needs and Experiences and their Impact.

CONTEXT: Family caregivers of patients with advanced cancer are integrally involved in communications regarding prognosis and end-of-life (EOL) planning and care. Yet little research has examined caregivers' communication experiences or the impact of these experiences on patients and caregivers at EOL. OBJECTIVES: Investigate cancer caregivers' communication experiences and potential impact on patient and caregiver outcomes. METHODS: Semistructured interviews with bereaved family cancer caregivers (N=19) about their communication needs and experiences as their loved one approached EOL and died. Audiotaped interviews were transcribed and thematically analyzed for communication-related themes. RESULTS: Caregivers described fulfilling many important communication roles including information gathering and sharing, advocating, and facilitating-often coordinating communication with multiple partners (e.g., patient, family, oncology team, hospital team). Caregivers reported that, among the many topics they communicated about, prognosis and EOL were the most consequential and challenging. These challenges arose for several reasons including caregivers' and patients' discordant communication needs, limited opportunity for caregivers to satisfy their personal communication needs, uncertainty regarding their communication needs and responsibilities, and feeling unacknowledged by the care team. These challenges negatively impacted caregivers' abilities to satisfy their patient-related communication responsibilities, which shaped many outcomes including end-of-life decisions, care satisfaction, and bereavement. CONCLUSION: Caregivers often facilitate essential communication for patients with advanced cancers yet face challenges successfully fulfilling their own and patients' communication needs, particularly surrounding prognostic and end-of-life conversations. Future research and interventions should explore strategies to help caregivers navigate uncertainty, create space to ask sensitive questions, and facilitate patient-caregiver discussions about differing informational needs.

The role of the Pseudomonas aeruginosa hypermutator phenotype on the shift from acute to chronic virulence during respiratory infection.

Chronic respiratory infection (CRI) with Pseudomonas aeruginosa (Pa) presents many unique challenges that complicate treatment. One notable challenge is the hypermutator phenotype which is present in up to 60% of sampled CRI patient isolates. Hypermutation can be caused by deactivating mutations in DNA mismatch repair (MMR) genes including mutS, mutL, and uvrD. In vitro and in vivo studies have demonstrated hypermutator strains to be less virulent than wild-type Pa. However, patients colonized with hypermutators display poorer lung function and a higher incidence of treatment failure. Hypermutation and MMR-deficiency create increased genetic diversity and population heterogeneity due to elevated mutation rates. MMR-deficient strains demonstrate higher rates of mucoidy, a hallmark virulence determinant of Pa during CRI in cystic fibrosis patients. The mucoid phenotype results from simple sequence repeat mutations in the mucA gene made in the absence of functional MMR. Mutations in Pa are further increased in the absence of MMR, leading to microcolony biofilm formation, further lineage diversification, and population heterogeneity which enhance bacterial persistence and host immune evasion. Hypermutation facilitates the adaptation to the lung microenvironment, enabling survival among nutritional complexity and microaerobic or anaerobic conditions. Mutations in key acute-to-chronic virulence "switch" genes, such as retS, bfmS, and ampR, are also catalyzed by hypermutation. Consequently, strong positive selection for many loss-of-function pathoadaptive mutations is seen in hypermutators and enriched in genes such as lasR. This results in the characteristic loss of Pa acute infection virulence factors, including quorum sensing, flagellar motility, and type III secretion. Further study of the role of hypermutation on Pa chronic infection is needed to better inform treatment regimens against CRI with hypermutator strains.

Eating disorders are associated with increased risk of fall injury and fracture in Swedish men and women.

In this retrospective cohort study, men and women with eating disorders (n = 8867) had higher risk of injurious falls and hip fractures than age, sex, and county-matched controls (n = 88670). INTRODUCTION: Eating disorders have been associated with decreased bone mineral density and increased fracture risk, but the association with fall injuries without fracture has not previously been investigated. Furthermore, fracture risk in men with eating disorders has been insufficiently studied. METHODS: In the present study, 8867 patients (9.4% men) with a diagnosed eating disorders and 88670 age-, sex-, and county-matched controls were investigated. RESULTS: The mean (standard deviation) age of the patients and controls was 41.6 (13.7) years and the follow-up time 9.6 (5.2, 14.4) years (median, interquartile range) for patients and 10.1 (5.5, 14.2) years for controls. The proportions of injurious falls without fracture (17.3% vs. 9.0%) and of hip fracture (1.6% vs. 0.7%) were substantially greater in patients with an eating disorder than in their corresponding population controls. In an unadjusted Cox proportional hazards model, individuals with an eating disorder had a higher risk of injurious falls without fracture (Hazard ratio (HR) 95% confidence interval (CI): 2.07 (1.96-2.18), and hip fracture (HR 2.30 (1.92-2.75)) than the risk observed in the controls. The HR for any investigated outcome associated with an eating disorder did not differ by sex or age (interaction term p > 0.10). The risk of injurious falls without fracture and hip fracture was increased in both women (HR 2.07 (1.95-2.19) and HR 2.41 (1.98-2.93), respectively) and men (HR 2.09 (1.76-2.49) and HR 1.84(1.12-3.02), respectively), with an eating disorder. CONCLUSION: The risk of injurious falls without fracture and of hip fracture is increased in both women and men with eating disorders, indicating measures to prevent both falls and fractures are important in these patients, regardless of age and sex.

Lack of pericytes leads to endothelial hyperplasia and abnormal vascular morphogenesis.

The association of pericytes (PCs) to newly formed blood vessels has been suggested to regulate endothelial cell (EC) proliferation, survival, migration, differentiation, and vascular branching. Here, we addressed these issues using PDGF-B-- and PDGF receptor-beta (PDGFR-beta)--deficient mice as in vivo models of brain angiogenesis in the absence of PCs. Quantitative morphological analysis showed that these mutants have normal microvessel density, length, and number of branch points. However, absence of PCs correlates with endothelial hyperplasia, increased capillary diameter, abnormal EC shape and ultrastructure, changed cellular distribution of certain junctional proteins, and morphological signs of increased transendothelial permeability. Brain endothelial hyperplasia was observed already at embryonic day (E) 11.5 and persisted throughout development. From E 13.5, vascular endothelial growth factor-A (VEGF-A) and other genes responsive to metabolic stress became upregulated, suggesting that the abnormal microvessel architecture has systemic metabolic consequences. VEGF-A upregulation correlated temporally with the occurrence of vascular abnormalities in the placenta and dilation of the heart. Thus, although PC deficiency appears to have direct effects on EC number before E 13.5, the subsequent increased VEGF-A levels may further abrogate microvessel architecture, promote vascular permeability, and contribute to formation of the edematous phenotype observed in late gestation PDGF-B and PDGFR-beta knock out embryos.

Role of PDGF-B and PDGFR-beta in recruitment of vascular smooth muscle cells and pericytes during embryonic blood vessel formation in the mouse.

Development of a vascular system involves the assembly of two principal cell types - endothelial cells and vascular smooth muscle cells/pericytes (vSMC/PC) - into many different types of blood vessels. Most, if not all, vessels begin as endothelial tubes that subsequently acquire a vSMC/PC coating. We have previously shown that PDGF-B is critically involved in the recruitment of pericytes to brain capillaries and to the kidney glomerular capillary tuft. Here, we used desmin and alpha-smooth muscle actin (ASMA) as markers to analyze vSMC/PC development in PDGF-B-/- and PDGFR-beta-/- embryos. Both mutants showed a site-specific reduction of desmin-positive pericytes and ASMA-positive vSMC. We found that endothelial expression of PDGF-B was restricted to immature capillary endothelial cells and to the endothelium of growing arteries. BrdU labeling showed that PDGFR-beta-positive vSMC/PC progenitors normally proliferate at sites of endothelial PDGF-B expression. In PDGF-B-/- embryos, limb arterial vSMC showed a reduced BrdU-labeling index. This suggests a role of PDGF-B in vSMC/PC cell proliferation during vascular growth. Two modes of vSMC recruitment to newly formed vessels have previously been suggested: (1) de novo formation of vSMC by induction of undifferentiated perivascular mesenchymal cells, and (2) co-migration of vSMC from a preexisting pool of vSMC. Our data support both modes of vSMC/PC development and lead to a model in which PDGFR-beta-positive vSMC/PC progenitors initially form around certain vessels by PDGF-B-independent induction. Subsequent angiogenic sprouting and vessel enlargement involves PDGF-B-dependent vSMC/PC progenitor co-migration and proliferation, and/or PDGF-B-independent new induction of vSMC/PC, depending on tissue context.

Endothelial-perivascular cell signaling in vascular development: lessons from knockout mice.

The importance of perivascular-endothelial cell interactions during blood vessel development is discussed in the light of recent findings in platelet-derived growth factor-B, platelet-derived growth factor receptor-beta, angiopoietin-1 and tie-2 knockout mice, which all show deficient development of perivascular cells. The initial formation of networks of endothelial tubes (vasculogenesis) does not seem to depend on the perivascular cells but subsequent vessel remodeling relies on mesenchymal-endothelial short-range signaling. Based on findings in platelet-derived growth factor and platelet-derived growth factor receptor knockout mice, a general model for the role of platelet-derived growth factors in smooth muscle development is proposed.

Paracrine PDGF-B/PDGF-Rbeta signaling controls mesangial cell development in kidney glomeruli.

Kidney glomerulus mesangial cells fail to develop in mice carrying targeted null mutations in the platelet-derived growth factor (PDGF)-B or PDGF-Rbeta genes. We have examined the pattern of expression of these genes and smooth muscle markers during kidney development, to address the possible mechanisms underlying the mutant phenotypes. In wild-type embryos, PDGF-B was expressed in vascular endothelial cells, particularly in capillary endothelial cells in the developing glomeruli, whereas PDGF-Rbeta was found in perivascular mesenchymal cells in the developing renal cortex. In the course of glomerular development, small groups of PDGF-Rbeta and desmin-expressing cells collected in the 'S'-shaped and early cup-shaped vesicles, and at later stages such cells were found in the glomerular mesangium. In PDGF-B or -Rbeta null embryos, some PDGF-Rbeta/desmin or desmin-positive cells, respectively, were seen in early cup-shaped vesicles, but fewer than in the wild type, and further development of the mesangium failed. In mouse chimeras composed of PDGF-Rbeta +/+ and -/- cells, the Rbeta-/- cells failed to populate the glomerular mesangium. Our results show that while the mesangial cell lineage is specified independently of PDGF-B/Rbeta, these molecules provide critical permissive signals in mesangial cell development. We propose a model in which mesangial cells originate from PDGF-Rbeta-positive progenitors surrounding the developing glomerular afferent and efferent arterioles, and are co-recruited in response to PDGF-B during angiogenic formation of the glomerular capillary tuft.