Differentiation and grafting of haemopoietic stem cells from early postimplantation mouse embryos

Haemopoietic stem cells evidently arise in early post-implantation mouse embryos at day 6 of gestation, a day earlier than previously thought (Moore & Metcalf, 1970). Disaggregated embryonic cells were injected into mice given a lethal dose of X-irradiation. The presence of donor haemoglobin (Whitney, 1978) and donor lymphocytic glucose phosphate isomerase (GPI) (Siciliano & Shaw, 1976) to detect donor erythrocytes and lymphocytes, respectively, were monitored by starch gel electrophoresis. The presence of donor cells was also assessed by using donor embryos carrying the T6 marker chromosomes. Decidual cells dissected free of embryos did not colonize any recipients. Disaggregated cells from early mouse embryos first colonized the liver and then repopulated the haemopoietic systems of recipients, producing adult donor haemoglobin within 2-3 days and donor GPI within 3-5 days. 80% of grafted X-irradiated recipients survived and donor markers were found in each of them. All nongrafted controls died within 14 days of X-irradiation and none of them showed donor markers. Disaggregated embryonic cells could be grafted across major histocompatibility barriers unlike adult bone marrow. Haemopoietic stem cells could not be identified in disaggregated cells from embryos aged less than 6 days gestation.     

An Examination of Commercial Kits for the Determination of Glutamic Oxaloacetic Transaminase (GOT) and Glutamic Pyruvic Transaminase (GPT) in Serum

Four kits for the detection of serum transaminase based on the spectrophotometric method and 15 kits based on the colorimetric procedure were evaluated. Two kits contained faulty reagents in both the SGOT and SGPT packages. Four of the 15 kits gave results which differed significantly from those of the reference method. The precision of the various kit procedures was adequate in each case for the determinations of SGOT and SGPT. The need to evaluate the adequacy of each kit in a routine operation before relying upon the results obtained with it is stressed.     

Effects of bile salts on the adsorption of a hydrophobic mutagen to dietary fiber

The effect of the bile salts, sodium cholate, deoxycholate, glycocholate and taurocholate, on the solubility in aqueous solution of the hydrophobic, environmental mutagen, 1,8-dinitropyrene (DNP), was examined. In the absence of bile salts, the DNP appeared to precipitate out of solution, whereas bile salts at a concentration of greater than or equal to 4 mM maintained the DNP in solution. In the presence of the model dietary fiber, alpha-cellulose, the DNP absorbed to this preferentially. Bile salts reduced this adsorption at low alpha-cellulose levels, but had little effect at high alpha-cellulose levels. The implication of these results is that bile salts have solubilising properties that could affect the distribution of hydrophobic molecules, including mutagens, in the digestive tract.     

Alteration of surfactant protein A expression in renal cell carcinoma

Surfactant protein-A (SP-A) belongs to a family of collagen-containing C-type lectins called collectins. SP-A is expressed by renal tubule epithelial cells. We investigated the distribution of SP-A in renal cell carcinomas (RCC) using immunohistochemical techniques and western blotting. We used 35 formalin fixed, paraffin embedded (FFPE) RCC tissue samples. We compared results with clinico-pathological parameters of RCC including age, sex, Fuhrman grade, tumor volume, tumor node metastasis (TNM) and clinical stage. SP-A was localized in the glomerulus and renal tubule epithelium in nontumor tissue and strong SP-A immunoreactivity was observed in tumor tissue. SP-A was expressed in the RCC tumor cells (64%) and nontumor cells (34%) in males and RCC tumor cells (90%) and nontumor cells (30%) in females. There was a significant correlation between SP-A immunoreactivity in tumor cells and gender, age, tumor diameter, Fuhrman grade and tumor diameter. Western blot analysis supported the immunohistochemical findings. We present evidence for involvement of SP-A in RCC and suggest that increased SP-A expression in RCC is associated with favorable prognosis.     

Underestimating Calorie Content When Healthy Foods Are Present: An Averaging Effect or a Reference-Dependent Anchoring Effect?

Objective

Previous studies have shown that estimations of the calorie content of an unhealthy main meal food tend to be lower when the food is shown alongside a healthy item (e.g. fruit or vegetables) than when shown alone. This effect has been called the negative calorie illusion and has been attributed to averaging the unhealthy (vice) and healthy (virtue) foods leading to increased perceived healthiness and reduced calorie estimates. The current study aimed to replicate and extend these findings to test the hypothesized mediating effect of ratings of healthiness of foods on calorie estimates.

Methods

In three online studies, participants were invited to make calorie estimates of combinations of foods. Healthiness ratings of the food were also assessed.

Results

The first two studies failed to replicate the negative calorie illusion. In a final study, the use of a reference food, closely following a procedure from a previously published study, did elicit a negative calorie illusion. No evidence was found for a mediating role of healthiness estimates.

Conclusion

The negative calorie illusion appears to be a function of the contrast between a food being judged and a reference, supporting the hypothesis that the negative calorie illusion arises from the use of a reference-dependent anchoring and adjustment heuristic and not from an ‘averaging’ effect, as initially proposed. This finding is consistent with existing data on sequential calorie estimates, and highlights a significant impact of the order in which foods are viewed on how foods are evaluated.     

Palatability and feeding preferences of Uresiphita maorialis (Lepidoptera: Crambidae) for three Sophora species

In a three-hour bioassay, we tested the palatability and feeding preferences of Uresiphita maorialis (kōwhai moth) for Sophora tetraptera, Sophora microphylla and Sophora prostrata. Palatability tests showed no differences among the Sophora species. Feeding preferences, on the other hand, showed that S. tetraptera and S. microphylla leaves are preferred over S. prostrata leaves. Our results support our field observations in Wellington city parks and gardens showing that S. tetraptera and S. microphylla plants frequently have higher densities of larvae than S. prostrata.     

Visualising health risks with medical imaging for changing recipients’ health behaviours and risk factors: Systematic review with meta-analysis

BackgroundThere is ongoing clinical and research interest in determining whether providing personalised risk information could motivate risk-reducing health behaviours. We aimed to assess the impact on behaviours and risk factors of feeding back to individuals’ images of their bodies generated via medical imaging technologies in assessing their current disease status or risk.Methods and findingsA systematic review with meta-analysis was conducted using Cochrane methods. MEDLINE, Embase, PsycINFO, CINAHL, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched up to July 28, 2021, with backward and forward citation searches up to July 29, 2021. Eligible studies were randomised controlled trials including adults who underwent medical imaging procedures assessing current health status or risk of disease, for which personal risk may be reduced by modifying behaviour. Trials included an intervention group that received the imaging procedure plus feedback of visualised results and assessed subsequent risk-reducing health behaviour. We examined 12,620 abstracts and included 21 studies, involving 9,248 randomised participants. Studies reported on 10 risk-reducing behaviours, with most data for smoking (8 studies; n = 4,308), medication use (6 studies; n = 4,539), and physical activity (4 studies; n = 1,877). Meta-analysis revealed beneficial effects of feedback of visualised medical imaging results on reduced smoking (risk ratio 1.11, 95% confidence interval [CI] 1.01 to 1.23, p = 0.04), healthier diet (standardised mean difference [SMD] 0.30, 95% CI 0.11 to 0.50, p = 0.003), increased physical activity (SMD 0.11, 95% CI 0.003 to 0.21, p = 0.04), and increased oral hygiene behaviours (SMD 0.35, 95% CI 0.13 to 0.57, p = 0.002). In addition, single studies reported increased skin self-examination and increased foot care. For other behavioural outcomes (medication use, sun protection, tanning booth use, and blood glucose testing) estimates favoured the intervention but were not statistically significant. Regarding secondary risk factor outcomes, there was clear evidence for reduced systolic blood pressure, waist circumference, and improved oral health, and some indication of reduced Framingham risk score. There was no evidence of any adverse effects, including anxiety, depression, or stress, although these were rarely assessed. A key limitation is that there were some concerns about risk of bias for all studies, with evidence for most outcomes being of low certainty. In particular, valid and precise measures of behaviour were rarely used, and there were few instances of preregistered protocols and analysis plans, increasing the likelihood of selective outcome reporting.ConclusionsIn this study, we observed that feedback of medical images to individuals has the potential to motivate risk-reducing behaviours and reduce risk factors. Should this promise be corroborated through further adequately powered trials that better mitigate against risk of bias, such interventions could usefully capitalise upon the widespread and growing use of medical imaging technologies in healthcare.

In a systematic review and meta-analysis, Gareth Hollands and colleagues study the relationship between receipt of visual feedback of results following medical imaging procedures and risk-reducing health-related behaviors.     

A model system for studying the adsorption of a hydrophobic mutagen to dietary fibre

The adsorption of 1,8-dinitropyrene (DNP) to alpha-cellulose has been studied as a model system for examining the adsorption of a hydrophobic mutagen to dietary fiber. Most of the DNP rapidly disappeared from an aqueous solution and partitioned between the glass wall of the test tube and the alpha-cellulose. Factors affecting DNP distribution included (i) the time of incubation, (ii) the final concentration of the solvent, dimethyl sulphoxide, in which the DNP has been dissolved, and (iii) the relative concentrations of DNP and alpha-cellulose. We suggest that this model system could be applied to other mutagens, and that alpha-cellulose would provide a useful standard fiber to permit inter-laboratory comparisons.