Inhibition of Bacterial Adherence on the Surface of Stents and Bacterial Growth in Bile by Bismuth Dimercaprol

Bacterial infection and biofilm formation on the surface of biliary stents is believed to be one of the main factors in stent occlusion. This study explored the role of the new reagent, bismuth dimercaprol, in preventing bacterial adherence and bacterial biofilm formation on the surface of biliary stents. Sterile porcine bile preparations, infected separately with Escherichia coli, Klebsiella pneumoniae, Enterobacter , and Enterococcus , were used as the perfusion media in an in vitro perfusion system. The bacterial growth in the media and the bacterial adherence on the surface of stents were tested when different concentrations of bismuth dimercaprol were used in the perfusion media. BisBAL (5 μ M ) did not inhibit the growth of any of the tested bacterial species. It did, however, significantly decrease the amount of bacteria adhering to the surface of stents for all bacterial strains except Escherichia coli . Bismuth dimercaprol (20 μ M ) significantly inhibited the growth of Escherichia coli, Klebsiella pneumoniae , and Enterobacter and, thereby, significantly decreased the amount of these bacteria adhering to the surface of stents. The unique bactericidal and anitbiofilm activities of bismuth thiols might contribute to delaying the process of biliary stent occlusion if the effective concentrations of bismuth thiols could be delivered to the target sites. The feasibility of this application of bismuth thiols deserves further investigation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44439/1/10620_2005_Article_2702.pd

Cross-education does not accelerate the rehabilitation of neuromuscular functions after ACL reconstruction: a randomized controlled clinical trial

Purpose: Cross-education reduces quadriceps weakness 8 weeks after anterior cruciate ligament (ACL) surgery, but the long-term effects are unknown. We investigated whether cross-education, as an adjuvant to the standard rehabilitation, would accelerate recovery of quadriceps strength and neuromuscular function up to 26 weeks post-surgery. Methods: Group allocation was randomized. The experimental (n = 22) and control (n = 21) group received standard rehabilitation. In addition, the experimental group strength trained the quadriceps of the non-injured leg in weeks 1–12 post-surgery (i.e., cross-education). Primary and secondary outcomes were measured in both legs 29 ± 23 days prior to surgery and at 5, 12, and 26 weeks post-surgery. Results: The primary outcome showed time and cross-education effects. Maximal quadriceps strength in the reconstructed leg decreased 35% and 12% at, respectively, 5 and 12 weeks post-surgery and improved 11% at 26 weeks post-surgery, where strength of the non-injured leg showed a gradual increase post-surgery up to 14% (all p ≤ 0.015). Limb symmetry deteriorated 9–10% more for the experimental than control group at 5 and 12 weeks post-surgery (both p ≤ 0.030). One of 34 secondary outcomes revealed a cross-education effect: Voluntary quadriceps activation of the reconstructed leg was 6% reduced for the experimental vs. control group at 12 weeks post-surgery (p = 0.023). Both legs improved force control (22–34%) and dynamic balance (6–7%) at 26 weeks post-surgery (all p ≤ 0.043). Knee joint proprioception and static balance remained unchanged. Conclusion: Standard rehabilitation improved maximal quadriceps strength, force control, and dynamic balance in both legs relative to pre-surgery but adding cross-education did not accelerate recovery following ACL reconstruction

Use of De-swirl nozzles to reduce the pressure drop in a rotating cavity with a radial inflow

A combined theoretical and experimental study is described in which de-swirl nozzles were used to reduce the radial pressure drop in a rotating cavity with a radial inflow of air. The nozzles, which were attached to the outer part of the cavity, were angled such that the angular speed of the air at inlet could be in the opposite direction to that of the cavity. Solutions of the momentum-integral equations were used to predict the resulting radial distributions of pressure throughout the cavity. Flow visualization was used to confirm the flow structure, and transducers attached to one of the rotating disks in the cavity were used to measure the radial pressure distributions. The measured pressures are in good agreement with the predicted values, and the pressure drop across the cavity can be significantly less than that associated with solid-body rotation

The use of de-swirl nozzles to reduce the pressure drop in a rotating cavity with a radial inflow

Copyright © 1989 by ASME.A combined theoretical and experimental study is described in which de-swirl nozzles were used to reduce the radial pressure drop in a rotating cavity with a radial inflow of air. The nozzles, which were attached to the outer part of the cavity, were angled such that the angular speed of the air at inlet could be in the opposite direction to that of the cavity. Solutions of the momentum-integral equations were used to predict the resulting radial distributions of pressure throughout the cavity. Flow visualization was used to confirm the flow structure, and transducers attached to one of the rotating discs in the cavity were used to measure the radial pressure distributions. Results are presented for 'swirl fractions' (that is, the ratio of the angular speed of the air leaving the nozzles to that of the cavity) in the range -0.4 to + 0.9, and for 0.01 w | Reφ-0-8 w and Reφ are the nondimensional flow rate and rotational Reynolds number, respectively. The measured pressures are in good agreement with the predicted values, and the pressure drop across the cavity can be significantly less than that associated with solid-body rotation. The flow rate produced by the pressure drop across the cavity is not unique: there are up to three possible values of flow rate for any given value of pressure drop

The use of de-swirl nozzles to reduce the pressure drop in a rotating cavity with a radial inflow

Copyright © 1989 by ASME.A combined theoretical and experimental study is described in which de-swirl nozzles were used to reduce the radial pressure drop in a rotating cavity with a radial inflow of air. The nozzles, which were attached to the outer part of the cavity, were angled such that the angular speed of the air at inlet could be in the opposite direction to that of the cavity. Solutions of the momentum-integral equations were used to predict the resulting radial distributions of pressure throughout the cavity. Flow visualization was used to confirm the flow structure, and transducers attached to one of the rotating discs in the cavity were used to measure the radial pressure distributions. Results are presented for 'swirl fractions' (that is, the ratio of the angular speed of the air leaving the nozzles to that of the cavity) in the range -0.4 to + 0.9, and for 0.01 w | Reφ-0-8 w and Reφ are the nondimensional flow rate and rotational Reynolds number, respectively. The measured pressures are in good agreement with the predicted values, and the pressure drop across the cavity can be significantly less than that associated with solid-body rotation. The flow rate produced by the pressure drop across the cavity is not unique: there are up to three possible values of flow rate for any given value of pressure drop

Use of De-swirl nozzles to reduce the pressure drop in a rotating cavity with a radial inflow

A combined theoretical and experimental study is described in which de-swirl nozzles were used to reduce the radial pressure drop in a rotating cavity with a radial inflow of air. The nozzles, which were attached to the outer part of the cavity, were angled such that the angular speed of the air at inlet could be in the opposite direction to that of the cavity. Solutions of the momentum-integral equations were used to predict the resulting radial distributions of pressure throughout the cavity. Flow visualization was used to confirm the flow structure, and transducers attached to one of the rotating disks in the cavity were used to measure the radial pressure distributions. The measured pressures are in good agreement with the predicted values, and the pressure drop across the cavity can be significantly less than that associated with solid-body rotation

Use of fins to reduce the pressure drop in a rotating cavity with a radial inflow

A combined theoretical and experimental study of radial inflow through a rotating cavity is reported. It is shown that radial fins attached to one of the disks are effective in reducing the pressure drop across the cavity. The mathematical model is an extension of earlier plane-disk momentum-integral methods, the fins are treated as rectangular rib elements and a rough-disk model is derived. Numerical solutions of the integral equations are given. An approximation linear solution is also derived. Experiments were conducted when both disks were plane and when one of the disks was fitted with 60 radial fins. Flow visualization revealed the flow structure in the cavity and confirmed some of the assumptions used in the theoretical model