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Background: Subcutaneous grafting/implantation of neonatal testis tissue/cells from diverse donor species into recipient mice can be used as an in vivo model to study testis development, spermatogenesis, and steroidogenesis. Ultrasound biomicroscopy (UBM) allows obtaining high definition cross‐sectional images of tissues at microscopic resolutions. Objectives: The present study was designed to (a) validate the use of UBM for non‐invasive monitoring of grafts/implants overtime and to (b) correlate UBM findings with the morphological attributes of recovered grafts/implants. Materials and methods: Testis tissue fragments (~14 mm3, each) and cell aggregates (100 × 106 cells, each) obtained from 1‐week‐old donor piglets (n = 30) were grafted/implanted under the back skin of immunodeficient mice (n = 6) in eight analogous sites per mouse. Three‐dimensional transcutaneous Doppler UBM was performed, and a randomly selected graft and its corresponding implant were recovered at 2, 4, 6, and 8 weeks. Results: Graft/implant weight (P =.04) and physical height (P =.03) increased overtime. The dynamics of physical length and volume increases over time differed between tissue grafts and cell implants (P =.02 and 0.01 for sample type*time interactions, respectively). UBM‐estimated volume was correlated with the post‐recovery weight and volume of the grafts/implants (r = 0.98 and r = 0.99, respectively; P <.001). Pre‐ and post‐recovery length and height of the grafts/implants were positively and strongly correlated (r = 0.50, P =.01; r = 0.70, P =.001) and so were the areas covered by cordal, non‐cordal, or fluid‐filled cavities between UBM and histology (r = 0.87, P <.001). Discussion and conclusion: UBM findings correlated with physical attributes of the grafts/implants, validating its use as a non‐invasive high‐fidelity tool to quantify the developmental changes in ectopic testis tissue grafts and cell implants, potentially leading to a reduction in the number of recipient mice needed for similar experiments. [ABSTRACT FROM AUTHOR]

Synthetic repellents based on di-ethyl 3-methyl benzamide (DEET) are a popular method of obtaining protection from mosquitoes and yet clear evidence for a protective effect against malaria has hitherto never been convincingly demonstrated. A household randomized trial was undertaken among a study population of 127 families (25%) in an Afghan refugee village in Pakistan to compare the efficacy of repellent soap (Mosbar containing 20% DEET and 0.5% permethrin) vs. a placebo lotion. Cases of falciparum and vivax malaria were detected by passive case detection at the camp's clinic. At the end of the 6 month trial 3.7% (23 of 618) of individuals in the Mosbar group had presented with one or more episodes of falciparum malaria compared with 8.9% (47 of 530) of the placebo group (odds ratio 0.44, 95% CI 0.25-0.76). 16.7% of the Mosbar group (103 of 618) presented with vivax malaria compared with 11.7% (62 of 530) of the placebo group, and thus no effect was shown against vivax malaria (odds ratio 1.29, 95% CI 0.86-1.94). A considerable proportion of individuals (22%) had presented with vivax malaria during the 7 months leading up to the trial and thus any intervention effect would be partially masked by relapsed infections. The distribution of mosquitoes among households was broadly similar between Mosbar and placebo groups. The repellent was popularly received and very few side-effects were reported. There is a case for giving repellents more prominence in public health as a preventive measure in regions where vectors bite in the early evening or in emergency situations such as epidemics or newly established refugee camps. [ABSTRACT FROM AUTHOR]