Lung transplant airway complications treated with biodegradable airway stents: The Dutch multi-center experience

INTRODUCTION: Treatment of post lung-transplant airway complications is challenging, and treatment with conventional airway stents is associated with adverse events. More recently, biodegradable airway stents (BDS) have been introduced and may be used to reduce these adverse events. In this study we explore the feasibility of treatment with BDS post lung transplant. METHODS: All patients treated with BDS in The Netherlands were included in this retrospective multicenter study. Feasibility, life span of the stent, occurrence of adverse events, and evolution of lung function were evaluated. RESULTS: Twelve patients (six malacia and six stenosis) received a total of 57 BDS, ranging from 1 to 10 BDS per patient. Six patients had been pretreated with conventional airway stents. Median stent life span was 112 days (range 66-202). No adverse events occurred during stent placement. In 5 out of 57 stent placements, a single additional bronchoscopy was necessary because of mucus accumulation (n = 4) or excessive granulation tissue (n = 1). All stent naïve patients became airway stent independent after treatment; all patients pretreated with conventional airway stents were still airway stent dependent at the end of follow up. CONCLUSION: Treatment with BDS is safe and feasible. Adverse events were mild and easily treatable. All patients with initial treatment with BDS were airway stent independent at the end of follow up with a median treatment of 4 BDS

The effect of oxygen and sulfhydryl reagents on the hydrolysis and the fermentation of chitin by Clostridium 9.1

Inhibition experiments employing sulfhydryl binding and sulfhydryl oxidizing reagents showed the presence of essential thiol groups in the chitinolytic system of Clostridium 9.1. Inhibition of fermentation by membrane-impermeable reagents was relieved upon addition of excess reductant, suggesting the involvement of essential thiol groups in sugar transport activity. The chitinolytic system and the fermentation of the bacterium appeared relatively insensitive to oxyge

Lung transplant airway complications treated with biodegradable airway stents:The Dutch multi-center experience

Introduction: Treatment of post lung-transplant airway complications is challenging, and treatment with conventional airway stents is associated with adverse events. More recently, biodegradable airway stents (BDS) have been introduced and may be used to reduce these adverse events. In this study we explore the feasibility of treatment with BDS post lung transplant. Methods: All patients treated with BDS in The Netherlands were included in this retrospective multicenter study. Feasibility, life span of the stent, occurrence of adverse events, and evolution of lung function were evaluated. Results: Twelve patients (six malacia and six stenosis) received a total of 57 BDS, ranging from 1 to 10 BDS per patient. Six patients had been pretreated with conventional airway stents. Median stent life span was 112 days (range 66–202). No adverse events occurred during stent placement. In 5 out of 57 stent placements, a single additional bronchoscopy was necessary because of mucus accumulation (n = 4) or excessive granulation tissue (n = 1). All stent naïve patients became airway stent independent after treatment; all patients pretreated with conventional airway stents were still airway stent dependent at the end of follow up. Conclusion: Treatment with BDS is safe and feasible. Adverse events were mild and easily treatable. All patients with initial treatment with BDS were airway stent independent at the end of follow up with a median treatment of 4 BDS.</p

Growth benefits provided by different arbuscular mycorrhizal fungi to Plantago lanceolata depend on the form of available phosphorus

Strains of arbuscular mycorrhizal fungi (AMF) differ markedly in the growth benefits they provide to plants. We investigated whether these differences depend on the chemical form of inorganic phosphorus. The closely related AMF Glomus custos and Rhizophagus irregularis were compared using Plantago lanceolata as the host plant, grown in quartz sand with either soluble orthophosphate or sparingly soluble hydroxyapatite as a sole source of phosphorus. In a growth experiment with AMF-inoculated plants in a climate chamber, sampling at 3-wk intervals enabled a detailed time-resolved analysis of shoot and root phosphorus concentrations and growth performance of P. lanceolata. The ability of AMF to enhance plant growth and deliver phosphate depended strongly on the identity of the available phosphorus source. In orthophosphate-amended substrate only modest differences in plant growth performance (dry matter accumulation and allocation, phosphorus acquisition) were observed between the two AMFs, despite evident AMF root colonization as shown by strain-specific mtLSU qPCR analysis. The treatment with hydroxyapatite however, created stringent growth-limiting conditions and significantly increased the growth benefit provided by R. irregularis over G. custos and the non-mycorrhizal treatment. Plants with R. irregularis could acquire much more phosphorus from apatite compared to G. custos. There were also differences in shoot-to-root dry matter allocation and plant tissue phosphorus concentrations between the R. irregularis and G. custos treatments. Our observations suggest that in experiments on the symbiosis between plants and mycorrhizal fungi more attention should be paid to the chemical form of phosphorus in soil