Electrospinning of Matrigel to Deposit a Basal Lamina-Like Nanofiber Surface

Schwann cell basal lamina is a nanometer-thin extracellular matrix layer that separates the axon-bound Schwann cells from the endoneurium of the peripheral nerve. It is implicated in the promotion of nerve regeneration after transection injury by allowing Schwann cell colonization and axonal guidance. Hence, it is desired to mimic the native basal lamina for neural tissue engineering applications. In this study, basal lamina proteins from BD Matrigel (growth factor-reduced) were extracted and electrospun to deposit nonwoven nanofiber mats. Adjustment of solute protein concentration, potential difference, air gap distance and flow rate produced a basal lamina-like construct with an average surface roughness of 23 nm and composed of 100-nm-thick irregular and relatively discontinuous fibers. Culture of embryonic chick dorsal root ganglion explants demonstrated that the fabricated nanofiber layer supported explant attachment, elongation of neurites, and migration of satellite Schwann cells in a similar fashion compared to electrospun collagen type-I fibers. Furthermore, the presence of nanorough surface featues significantly increased the neurite spreading and Schwann cell growth. Sciatic nerve segment incubation also showed that the construct is promigratory to nerve Schwann cells. Results, therefore, suggest that the synthetic basal lamina fibers can be utilized as a biomaterial for induction of peripheral nerve repair.     

A rare case of necrotizing fasciitis of the external ear

A 15 months old boy was referred to our emergency department with fever since 3 days and bilateral otorrhoe. Examination of the ears revealed an edematous and erythematous pinna at the left side, with necrosis of the tragus. Because of progression of the necrosis, an urgent debridement was performed and antimicrobial therapy was started.Necrotizing fasciitis (NF) is a progressive and potential fatal bacterial infection of the subcutaneous tissue, rapidly spreading along fascial planes. In the head and neck area NF is very uncommon. Most cases involve only the neck, usually from infections of dental or pharyngeal origin. In the English literature we only found one case of NF extending from an external otitis in an adult patient.     

Comparison of first trimester transvaginal anatomy scan to the second trimester structural survey in normal weight and obese populations: a pilot study

Purpose: To compare visualization of first trimester fetal anatomic transvaginal ultrasound (TVUS) to the second trimester transabdominal anatomic ultrasound (TAU) in normal weight and obese patients.

Materials and methods: In a prospective cross-sectional study design, 25 women underwent a TVUS between 12 and 14 weeks, and a TAU at 18–22 weeks. For each anatomic structure, the percentage of patients achieving optimal visualization was recorded. Risk ratios for visualizing a structure in the second trimester versus the first were calculated.

Results: Twenty-five patients underwent a TVUS and 24 completed the TAU. The average BMI in the obese and nonobese groups was 34?kg/m² and 23?kg/m², respectively. All structures were more consistently visualized during the TAU for the both groups. The cardiac views, hands and feet were more difficult to visualize in all the patients at both scan times but were more frequently visualized in the TAU. For the obese patients, hands, feet, cardiac and spine views were less frequently visualized in both the scans. The posterior fossa and profile views were more difficult to obtain in the TVUS.

Conclusions: The first trimester TVUS detects many of the structures assessed during an anatomic survey; however, it is not superior to the second trimester TAU in normal weight and obese patients.