The contribution of a directional preference of stiffness to the efficacy of prophylactic sacral dressings in protecting healthy and diabetic tissues from pressure injury: computational modelling studies

The sacral region is the most common site for pressure injuries (PIs) associated with lying in bed, and such sacral PIs often commence as deep tissue injuries (DTIs) that later present as open wounds. In complex patients, diabetes is common. Because, among other factors, diabetes affects connective tissue stiffness properties, making these tissues less able to dissipate mechanical loads through physiological deformations, diabetes is an additional biomechanical risk factor for PIs and DTIs. A preventive measure with established successful clinical outcomes is the use of sacral prophylactic dressings. The objective of this study has been to expand our previous work regarding the modes of action and biomechanical efficacy of prophylactic dressings in protecting the soft tissues adjacent to the sacrum by specifically examining the role of a directional stiffness preference (anisotropy) of the dressing while further accounting for diabetic tissue conditions. Multiple three‐dimensional anatomically detailed finite element (FE) model variants representing diabetic tissue conditions were used, and tissue loading state data were compared with healthy tissue simulations. We specifically compared soft tissue exposures to elevated internal shear stresses and strain energy densities (SED) near the sacrum during supine weight bearing on a standard (foam) hospital mattress without a dressing, with a prophylactic dressing lacking directional stiffness preferences and with an anisotropic dressing. Our results have clearly shown that an anisotropic dressing design reduces the peak tissue stresses and exposure to sustained tissue deformations in both healthy and diabetic cases. The present study provides additional important insights regarding the optimal structural and material design of prophylactic dressings, which in turn, informs clinicians and decision makers regarding beneficial features.     

Misalignments of purpose and power in an early Canadian interprofessional education initiative

Interprofessional education (IPE) has been widely incorporated into health professional curricula and accreditation standards despite an arguably thin base of evidence regarding its clinical effects, theoretical underpinnings, and social implications. To better understand how and why IPE first took root, but failed to grow, this study examines one of the earliest documented IPE initiatives, which took place at the University of British Columbia between 1960 and 1975. We examined a subset of 110 texts (academic literature, grey literature, and unpublished records) from a larger study that uses Critical Discourse Analysis to trace the emergence of IPE in Canada. We asked how IPE was promoted and received, by whom, for what purposes, and to what effects. Our analysis demonstrates that IPE was promoted as a response to local challenges for the Faculty of Medicine as well as national challenges for Canada’s emerging public healthcare system. These dual exigencies enabled the IPE initiative, but they shaped it in somewhat divergent ways: the former gave rise to its core component (a health sciences centre) and the latter its ultimate purpose (increasing the role of non-medical professions in primary care). Reception of the initiative was complicated by a further tension: nurses and allied health professionals were sometimes represented as independent experts with unique knowledge and skills, and sometimes as assistants or substitutes for medical doctors. We relate the successes and frustrations of this early initiative to particular (mis)alignments of purpose and relationships of power, some of which continue to enable and constrain IPE today.     

Cancer-associated fibroblasts in the tumor microenvironment of tongue carcinoma is a heterogeneous cell population

ObjectivesTo examine different immunophenotypes of cancer-associated fibroblasts (CAFs) in tongue squamous cell carcinoma (TSCC) and to investigate how they related to clinical outcomes.MethodsSerial sections from 54 cases of TSCC were immunohistochemically stained with α-smooth muscle actin (αSMA, CAF marker) to determine CAF density, and double-immunostained with αSMA combined with CD80 and CD86 (myeloid/monocytic-derived cell markers), Nanog (mesenchymal stem cell marker) and CD133 (hematopoietic/endothelial stem cell marker). Density of cells co-expressing these marker combinations was semi-quantitatively assessed in 5 randomly selected high power fields within the tumor area and scored as 1 – one-to-five stained cells in each field, 2 – more than 5 stained cells in each field; any finding less than score 1, was allocated a score of 0.ResultsThere were 26 CAF-poor, 16 CAF-rich and 12 CAF-intermediated cases. CD86⁺αSMA⁺ cells were the most frequent (80.4%) followed by CD80⁺αSMA⁺ (72%) and Nanog⁺αSMA⁺ cells (56%). The CD133⁺αSMA⁺ phenotype was found only in association with blood vessels. High density of αSMA⁺ CAFs was associated with disease recurrence and poor survival (p < 0.05). Increased density of CD86⁺αSMA⁺ cells was significantly associated with CAF-rich tumors and with poor survival (p < 0.05).ConclusionIn TSCC, CAFs demonstrate heterogeneous and overlapping phenotypes with the myeloid/monocytic type being the most frequent and having an impact on the clinical outcomes. Further studies are needed in order to further characterize CAF phenotypes in carcinomas of various oral sites, as this may open new frontiers for personalized medicine.     

Effects of Immigration on Infant Feeding Practices in an Inner City,Low Socioeconomic Community

ObjectiveInfant feeding practices have been shown to differ between immigrants and non-immigrants in the United States. Our study characterizes feeding practices of infants of immigrant versus American-born mothers followed in an inner city Pediatric continuity clinic serving predominantly low socioeconomic status families.MethodsA survey was given to 102 parents of infants ranging from 12 to 15 months of age who attended the clinic. Parents were asked about their country of origin, ethnic background and time since immigration to the US. They were also asked about their breastfeeding and early infant feeding practices. Statistical significance was estimated using chi-squared tests.ResultsNot only were breastfeeding rates higher among immigrant mothers compared to American-born mothers (88% vs. 63%, p-value 0.008) but they introduced commercially available baby food less frequently (37% vs. 52%, p-value 0.03) and rarely fed their infants fast food (22% vs. 50%, p-value<0.001). Moreover, breast feeding rates decreased with duration of residence in the United States. 53% of immigrant mothers who have been in the United States for less than 5 years breastfed for over 6 months versus 22% of immigrant mothers who resided more than 5 years in the United States (p-value 0.02). The vast majority of immigrant mothers who switched to formula did so because they felt their milk production was insufficient (93%) whereas the vast majority of American-born mothers stopped breastfeeding because they perceived it to be painful (64%, p value 0.001).ConclusionsInfant feeding practices differ between immigrant and American-born mothers and the differences diminish the longer the mothers reside in the United States. These differences stem from differences in cultural perceptions of breastfeeding. Therefore, in educating mothers about infant feeding, physicians should strongly consider cultural and ethnic factors.     

Heparanase Levels Are Elevated in the Plasma of Pediatric Cancer Patients and Correlate with Response to Anticancer Treatment

Heparanase is an endoglycosidase that specifically cleaves heparan sulfate (HS) side chains of heparan sulfate proteoglycans, the major proteoglycan in the extracellular matrix (ECM) and cell surfaces. Heparanase upregulation was documented in an increasing number of primary human tumors, correlating with reduced postoperative survival rate and enhanced tumor angiogenesis. The purpose of the current study was to determine heparanase levels in blood samples collected from pediatric cancer patients using an ELISA method. Heparanase levels were elevated four-fold in the plasma of cancer patients compared with healthy controls (664 ± 143 vs 163 ± 18 pg/ml, respectively). Evaluating plasma samples following anticancer therapy revealed reduced heparanase levels (664 ± 143 vs 429 ± 82 pg/ml), differences that are statistically highly significant (P = .0048). Of the 55 patients with complete remission (CR) or very good partial remission (VGPR) at restaging, 41 (74.5%) had lower heparanase amounts, whereas 14 patients (25.5%) had similar or higher amounts of plasma heparanase. All nine patients with stable or advancing disease had similar or elevated levels of heparanase on restaging. The results show that heparanase levels are elevated in the plasma of pediatric cancer patients and closely correlate with treatment responsiveness, indicating that heparanase levels can be used to diagnose and monitor patient''s response to anticancer treatment.