Sequential adaptation of perfusion and transport conditions significantly improves vascular construct recellularization and biomechanics

Recellularization of ex vivo‐derived scaffolds remains a significant hurdle primarily due to the scaffolds subcellular pore size that restricts initial cell seeding to the scaffolds periphery and inhibits migration over time. With the aim to improve cell migration, repopulation, and graft mechanics, the effects of a four‐step culture approach were assessed. Using an ex vivo‐derived vein as a model scaffold, human smooth muscle cells were first seeded onto its ablumen (Step 1: 3 hr) and an aggressive 0–100% nutrient gradient (lumenal flow under hypotensive pressure) was created to initiate cell migration across the scaffold (Step 2: Day 0 to 19). The effects of a prolonged aggressive nutrient gradient created by this single lumenal flow was then compared with a dual flow (lumenal and ablumenal) in Step 3 (Day 20 to 30). Analyses showed that a single lumenal flow maintained for 30 days resulted in a higher proportion of cells migrating across the scaffold toward the vessel lumen (nutrient source), with improved distribution. In Step 4 (Day 31 to 45), the transition from hypotensive pressure (12/8 mmHg) to normotensive (arterial‐like) pressure (120/80 mmHg) was assessed. It demonstrated that recellularized scaffolds exposed to arterial pressures have increased glycosaminoglycan deposition, physiological modulus, and Young's modulus. By using this stepwise conditioning, the challenging recellularization of a vein‐based scaffold and its positive remodeling toward arterial biomechanics were obtained.     

Factor structure of the WAIS-R for an incarcerated population

The factor structure of the Wechsler Adult Intelligence Scale-Revised (WAIS-R) for a large sample of incarcerated individuals (N = 234) was investigated. A principal components analysis followed by Varimax rotation identified the familiar Perceptual Organization and Verbal Comprehension factors. Coefficients of congruence between the current factors and those of the WAIS-R standardization sample indicate a high degree of correspondence. Thus, empirical support was provided for interpretation of WAIS-R Performance and Verbal IQs in this population.     

Compliance with and acceptability of two fortified balanced energy protein supplements among pregnant women in rural Nepal

Some evidence suggests that balanced energy protein (BEP) supplements taken during pregnancy and lactation can have positive effects on birth outcomes such as small‐for‐gestational age and birthweight, but more evidence is needed on the long‐term use and acceptability of such supplements. We conducted a mixed‐methods formative research study to assess and compare compliance with and acceptability of two BEP supplements, a lipid‐based peanut paste and a biscuit, to identify BEP supplements for subsequent inclusion in an efficacy trial. We conducted an 8‐week feeding trial of daily supplementation among two groups of 40 pregnant women each in rural Nepal. Compliance data were collected and supplements distributed at the weekly visits. Sensory properties of the supplements were assessed using a 7‐point Likert scale. In addition, in‐depth interviews with women (n = 16), family members (n = 6) and health workers (n = 6) and focus group discussions (FGDs) (n = 4) were conducted to explore themes related to general use and intention of future use of the supplement. Overall self‐reported compliance was high: medians of 91.1% in the lipid‐based peanut paste group and 96.4% in the biscuit group. Both supplements were rated highly on overall likability (median score 6/7) and sensory properties. Qualitative findings showed that sustained use of the supplements was attributed to expected health benefits, favourable sensory attributes, and family support. The FGDs suggested providing the option to choose between more than one type/flavour of supplements to improve compliance. Sharing was mostly evident in the first week with higher sharing reported in the biscuit group.     

Replication Kinetics for a Reporter Merkel Cell Polyomavirus

Merkel cell polyomavirus (MCV) causes one of the most aggressive human skin cancers, but laboratory studies on MCV replication have proven technically difficult. We report the first recombinase-mediated MCV minicircle (MCVmc) system that generates high levels of circularized virus, allowing facile MCV genetic manipulation and characterization of viral gene expression kinetics during replication. Mutations to Fbw7, Skp2, β-TrCP and hVam6p interaction sites, or to the stem loop sequence for the MCV-encoded miRNA precursor, markedly increase viral replication, whereas point mutation to an origin-binding site eliminates active virus replication. To further increase the utility of this system, an mScarlet fusion protein was inserted into the VP1 c-terminus to generate a non-infectious reporter virus for studies on virus kinetics. When this reporter virus genome is heterologously expressed together with MCV VP1 and VP2, virus-like particles are generated. The reporter virus genome is encapsidated and can be used at lower biosafety levels for one-round infection studies. Our findings reveal that MCV has multiple, self-encoded viral restriction mechanisms to promote viral latency over lytic replication, and these mechanisms are now amenable to examination using a recombinase technology.     

A systems approach to investigating interpersonal strife

Investigated the relationships between computer-simulated, in-vitro interactional personality behavior and various indices of interpersonal relationships using data collected from 31 families. Interpersonal strife scores for each of 31 family triads developed via mathematical simulation using a systems approach correlated significantly with 6 of the 10 personal relationship variables. Stepwise regression analysis showed that strife for this sample was allied most closely with rigid, unstable interpersonal interactions. It was concluded that (1) mathematical simulation of interpersonal behavior shows validity for group behavior as well as dyadic behavior; and (2) the systems approach offers a unique, in-vitro way of studying and diagnosing interpersonal difficulties.