Dermagraft treatment of diabetic ulcers

Neonatal peroneal neurapraxia is an uncommon transient palsy resulting from intrauterine stretching of the infant's peroneal nerve due to malpositioning (usually breech). This article reviews the literature, discusses the pathophysiology, and presents two new cases.     

Tibial and peroneal bypass in severe occlusive disease of the lower extremities

Symptomatic arteriosclerotic occlusive disease involving the femoral and proximal popliteal arteries is currently best treated by reversed autogenous saphenous vein bypass graft. Severe occlusive disease frequently includes the popliteal and/or origin of the trifurcation vessels with reconstitution of one or more of the vessels in the lower leg. We have used distal bypass 97 times in 90 patients during the past decade. There was only one postoperative death in the series in spite of the advanced age and concurrent disease in the majority of the patients. Our indications for operation continue to be relief of pain or salvage of an extremity. We rely on high quality preoperative angiograms for selection of vessels to receive the bypass. The posterior tibial artery was used in 63 of the cases, while the anterior tibial and peroneal were used in 24 and 10 cases, respectively. There were 11 immediate inhospital failures in this series of 97 cases requiring amputation in five. Three additional patients had amputations during the ensuing several months. Of the 85 grafts functioning at the time of discharge from the hospital, 16 or (18.8%) failed during the first years. Grafts that remained patent for one year have a high incidence of long term patency which is in keeping with other reported series.     

Long-period grating fabricated by periodically tapering standard single-mode fiber

We fabricated an asymmetric long-period grating (LPG) by periodically tapering a section of standard single-mode fiber using a resistive filament heating. The LPG exhibits large peak transmission attenuation of -30.31 dB with only 22 periods in a 1.0 cm long optical fiber and possesses unique characteristics for sensing applications. The bending and strain sensitivities are 1.74 nm m and 1.11 pm/mu epsilon, respectively. The polarization dependent loss is large, up to 11.65 dB, which is caused by an asymmetric index profile in the cross section of the tapered LPG.     

Effects of anion species and concentration on the removal of Cr(VI) by a microalgal isolate, Chlorella miniata

The presence of nitrate, chloride and sulfate anions on the removal of Cr(VI) by Chlorella miniata was investigated. Results of kinetic studies indicated that the equilibrium time in each anion system increased with increases of the initial salt concentration, and the inhibitory order was NO(3)(-)>Cl(-)>SO(4)(2-) for Cr(VI) removal and was SO(4)(2-)>Cl(-) approximately NO(3)(-) for the biosorption of the bioreduced Cr(III). The inhibitory effect caused by different anions was attributed to biosorption mechanism and metal speciation. Since both biosorption and bioreduction were involved in Cr(VI) removal, the presence of anions could compete with Cr(VI) for the adsorption sites, and the affinity of anions to the algal biomass followed the order of NO(3)(-)>Cl(-)>SO(4)(2-), which was consistent with their inhibitory order on Cr(VI) removal. Speciation results also indicated that the formation of CrO(3)SO(4)(2-) in the sulfate system made it easier to be adsorbed on the biomass than HCrO(4)(-). The biosorption-bioreduction model further suggested that the bioreduction rate constant k decreased with increases of anion concentrations ranging from 0 to 0.5M, and followed the order of SO(4)(2-)>Cl(-)>NO(3)(-). The biosorption constant b also decreased with anion concentrations in the range of 0-0.2M, suggesting that this parameter was more sensitive to anion effects than the k values. The higher b values in the sulfate than in the nitrate and chloride systems indicated that Cr(VI) in the sulfate system was more easily adsorbed on the algal biomass. These findings demonstrated that the presence of anions significantly affected the removal of Cr(VI) by C. miniata. Since chloride, nitrate and sulfate ions are commonly found in industrial wastewater, it may be necessary to eliminate these ions prior to chromium removal.     

Three‐Dimensional Database Mining Identifies a Unique Chemotype that Unites Structurally Diverse Botulinum Neurotoxin Serotype A Inhibitors in a Three‐Zone Pharmacophore

A search query consisting of two aromatic centers and two cationic centers was defined based on previously identified small molecule inhibitors of the botulinum neurotoxin serotype A light chain (BoNT/A LC) and used to mine the National Cancer Institute Open Repository. Ten small molecule hits were identified, and upon testing, three demonstrated inhibitory activity. Of these, one was structurally unique, possessing a rigid diazachrysene scaffold. The steric limitations of the diazachrysene imposed a separation between the overlaps of previously identified inhibitors, revealing an extended binding mode. As a result, the pharmacophore for BoNT/A LC inhibition has been modified to encompass three zones. To demonstrate the utility of this model, a novel three‐zone inhibitor was mined and its activity was confirmed.     

Topical delivery of silver nanoparticles promotes wound healing

Wound healing is a complex process and has been the subject of intense research for a long time. The recent emergence of nanotechnology has provided a new therapeutic modality in silver nanoparticles for use in burn wounds. Nonetheless, the beneficial effects of silver nanoparticles on wound healing remain unknown. We investigated the wound-healing properties of silver nanoparticles in an animal model and found that rapid healing and improved cosmetic appearance occur in a dose-dependent manner. Furthermore, through quantitative PCR, immunohistochemistry, and proteomic studies, we showed that silver nanoparticles exert positive effects through their antimicrobial properties, reduction in wound inflammation, and modulation of fibrogenic cytokines. These results have given insight into the actions of silver and have provided a novel therapeutic direction for wound treatment in clinical practice.