Skillful surgeons can do amazing things in extremely small places, but finding better ways to suture tiny blood vessels has been an ongoing challenge for even the best.

University of Delaware researchers show how a new peptidebased hydrogel could one day make that reconnection process easier to perform and less likely to fail.

The new process uses a hydrogel developed by Daniel J. Smith. Other collaborators include Katelyn NagySmith, who has recently completed all requirements for her doctorate at UD, and Joel Schneider, who was a professor at UD and now is in the Chemical Biology Laboratory at the National Cancer Institute.

Also part of the study were researchers from Johns Hopkins University School of Medicine and the Department of Electrical and Computer Engineering at Johns Hopkins.

Smith designed the peptide, building on a selfassembling process developed more than a decade ago by Schneider while he was a professor in UD’s Department of Chemistry and Biochemistry, and Darrin Pochan, professor and chair of UD’s Department of Materials Science and Engineering.

NagySmith did the microscopy, using a transmission electron microscope at the National Cancer Institute to show how the fibres change when exposed to ultraviolet light.

The way tiny vessels are reconnected now includes stitches applied in microsurgery. But the tiny, thinwalled vessels are fragile and prone to damage in handling.

The peptidebased hydrogel can be tuned in precise ways with a specific amino acid, allowing the material to change form several times during a procedure

Boston Children

You can whack it with a hammer, attack it with a drill, even stab it with a screwdriver. But try as you might, you won’t be able to tamper with a high-tech pill dispenser designed by mechanical engineering students at Johns Hopkins University’s Whiting School of Engineering.

Which is exactly the point.

The U.S. Centers for Disease Control and Prevention has estimated that drug overdoses kill more than 44,000 Americans annually, including more than 16,000 deaths from prescription drugs. Federal officials also say that at least one in 20 Americans ingests drugs prescribed for someone else. Concerned about these alarming statistics, experts at the Johns Hopkins Bloomberg School of Public Health’s Center for Injury Research and Policy challenged a team of Johns Hopkins senior mechanical engineers to design and build an anti-theft and tamper-resistant pill dispenser.

‘We needed this personal pill ‘safe’ to have tamper resistance, personal identification capabilities, and a locking mechanism that allows only a pharmacist to load the device with pills,’ said Kavi Bhalla, assistant professor at the university’s Bloomberg School of Public Health and one of the team’s mentors for the project.

Classmates Megan Carney, Joseph Hajj, Joseph Heaney, and Welles Sakmar

Using apheresis to remove a serum protein called soluble Fms-like tyrosine kinase-1 (Sflt-1) may help pregnant women with severe preeclampsia safely delay delivery, according to a pilot study.

‘Based on recent advances in the understanding of this condition, we and others are developing treatments for preeclampsia to allow women to safely prolong their pregnancy if they are suffering from very preterm preeclampsia,’ first author Ravi Thadhani, MD, MPH, from Massachusetts General Hospital in Boston, said in a press release.

Symptoms of preeclampsia include high blood pressure and proteinuria. The condition affects between 3% and 8% of pregnancies worldwide and can be harmful or even fatal to both the mother and newborn. Because of limited understanding about its underlying mechanisms, no cure exists other than delivery, which can be problematic if preeclampsia develops very early in pregnancy, the authors note.

In the open pilot study, Dr Thadhani and colleagues tested the safety and efficacy of removing sFlt-1 from the blood of pregnant women with very preterm preeclampsia. The serum protein sFLT-1 acts as a receptor for vascular endothelial growth factor. By inhibiting vascular endothelial growth factor activity, sFTL-1 modifies blood vessel growth. Women with preeclampsia often have elevated sFTL-1 levels.

Using apheresis, researchers removed the blood from 11 pregnant women and passed it through a negatively charged dextran sulfate column to bind and remove the positively charged sFLT-1. Participants were aged 20 to 38 years and were between 23 to 32 weeks of gestation. Inclusion criteria included systolic blood pressure of 140 mm Hg or higher or diastolic blood pressure of 90 mm Hg or higher, new-onset protein/creatinine ratio higher than 0.30 g/g, and sFLT-1/placental growth factor ratio higher than 85.

Apheresis resulted in an 18% (range, 7% – 28%) reduction in mean sFLT-1 levels, as well as reductions of 44% in protein/creatinine ratios.

Pregnancy continued 8 days after admission (range, 2 – 11 days) in six women treated once with apheresis, and 12 days (range, 7 – 19 days) in five women treated multiple times. In comparison, delivery occurred after 3 days (range, 0 – 14 days) in untreated women with preeclampsia (n = 22) and women who delivered preterm for other reasons (n = 22); the control participants, who had been treated contemporaneously, were matched to the treated women for several factors, including gestational age at delivery.

Although antihypertensive treatments were withheld the morning of the apheresis treatment, the most common adverse effect of apheresis was transient hypotension, which was treated with saline hydration and decreasing blood flow through the column. Hypotension was not severe enough to cause any of the women to stop treatments. No significant changes in foetal heart monitoring occurred during apheresis.

Babies born to apheresis-treated women needed fewer days of supplemental oxygen than babies born to untreated women. However, neonatal test results, total days in the neonatal ICU, and days spent in the hospital did not differ between the groups.

‘Our pilot study suggested we can safely prolong pregnancy when we target removal of sFlt-1 in women with severe preterm preeclampsia, and we hope this is confirmed in randomized trials,’ Dr Thadhani. MedScape