Technique and Clinical Outcomes of Combined Stent Placement for Postthrombotic Chronic Total Occlusions of the Iliofemoral Veins.

PURPOSE: To evaluate the technical aspects and early clinical results of combined stent placement for the management of postthrombotic syndrome (PTS) in chronic total occlusions (CTOs) of the iliofemoral veins. MATERIALS AND METHODS: A total of 81 consecutive patients (mean age, 57 y; 37 men; 81 limbs; 65 left limbs) with postthrombotic CTO of the iliofemoral veins treated with combined stent placement in a single institution from January 2013 to December 2014 were retrospectively analyzed. Wallstents were used for femoral inflow and E-Luminexx stents for iliac outflow. Technical aspects, quality of life (QOL), stent patency, and Villalta scores were recorded at follow-up. Primary, primary assisted, and secondary patency rates were estimated with Kaplan-Meier methods with the log-rank test. RESULTS: Percutaneous recanalization was successful in 77 of 81 limbs (95.1%). Stents were deployed in all iliofemoral occlusions, with two stents in 63 lesions (77.8%) lesions and three stents in 18 lesions (22.2%). Venous perforation occurred in 32 patients (37.4%) and was resolved in all cases after stent placement. Back pain occurred during balloon angioplasty (93.8%) and persisted after stent placement in 56.8% of patients. However, the symptoms were self-limiting without further therapy. QOL and Villalta scores were significantly improved during a median follow-up of 19 months (range, 1-38 mo; P < .01). The 2-year primary, primary assisted, and secondary cumulative stent patency rates were 81.5%, 91.4%, and 93.8%, respectively. CONCLUSIONS: Combined stent placement is an effective, safe, and feasible method of management of PTS in iliofemoral CTO until commercial venous stents designed for PTS become available.

Is damage control orthopedics essential for the management of bilateral femoral fractures associated or complicated with shock? An animal study.

BACKGROUND: The maximum score of a single anatomic system, the Injury Severity Score, may not reflect the overall damage inflicted by bilateral femoral fractures and justify the strategy of damage control orthopedics (DCO). It is necessary to investigate effects of various therapeutic procedures on such fractures with or without shock to facilitate correct decision making on DCO. METHODS: A model of bilateral femoral fractures was made in 36 of 48 male New Zealand White rabbits. A model of bilateral femoral shaft fractures associated with shock was made. After resuscitation, a reamed intramedullary nailing fixation was performed in the first group (IM group), and an external fixation device applied in the second group (EF group), and the fractures in the third group (control group) were supported with splints only. They were divided into four groups: shock with IM nailing (shock-IM), shock with external fixation (shock-EF), shock with conservative method (shock-Cons), and intramedullary nailing without shock (nonshock-IM). Vital signs and inflammatory reactions were recorded. Thirty-six hours after the therapeutic procedures in four groups, the animals were killed for histologic evaluation. RESULTS: The changes of vital signs were most significant in shock-IM group (p < 0.05). The exaggerated levels of interleukin-6, Interleukin-10, and tumor necrosis factor alpha concentrations demonstrated a significant difference between all the groups-shock-IM and other groups (p < 0.05). As to histologic appearances, the statistical difference varies from organ to organ. There is highly significant difference when the IM group is compared with the other two groups as far as lungs are concerned. As to the liver, there is only significant difference between the IM group and the control group. In terms of kidney and heart, there is no significant difference cross the groups. As to histologic appearances, there is highly significant difference in lungs between shock-IM group and other three groups. There is significant difference in liver between the shock-IM group and the shock-Cons group (p < 0.05). Kidneys and heart were less affected cross the groups. CONCLUSIONS: In this study, an early reamed intramedullary nailing fixation procedure resulted in more adverse effects on system stress, inflammatory response, and multiple organs. The injuries also cause histologic damages to lungs and liver. Therefore, early reamed intramedullary nailing fixation may pose a potential risk of developing complications and adopting the DCO strategy may be more preferable. Shock and IM combined cause most severe damages, followed by IM without shock, shock plus EF, and shock plus conservative procedure in that order. If IM must be used for some reasons, it is desirable be delayed until shock has been fully controlled and vasculorespiratory stability restored.

Chitosan and its derivatives--a promising non-viral vector for gene transfection.

The ability of a vector to ferry gene into targeted cells is the premise of improving gene-transfer efficiency. Chitosan, a naturally occurring cationic polysaccharide, has been shown to excel in transcellular transport. This attribute has been fully reflected in chitosan-mediated gene transfection systems. The objective of this review is to summarize the recent encouraging advances in unveiling the mechanism of cell entry and application of chitosan and its derivatives as novel non-viral vectors. It is our belief that researchers will uncover more truth about chitosan-based vector and realize the long-term goal of gene transfection--produce the desired clinical effect.

Effect of the 5-HT4 receptor and serotonin transporter on visceral hypersensitivity in rats.

Visceral hypersensitivity plays an important role in motor and sensory abnormalities associated with irritable bowel syndrome, but the underlying mechanisms are not fully understood. The present study was designed to evaluate the expression of the 5-HT(4) receptor and the serotonin transporter (SERT) as well as their roles in chronic visceral hypersensitivity using a rat model. Neonatal male Sprague-Dawley rats received intracolonic injections of 0.5% acetic acid (0.3-0.5 mL at different times) between postnatal days 8 and 21 to establish an animal model of visceral hypersensitivity. On day 43, the threshold intensity for a visually identifiable contraction of the abdominal wall and body arching were recorded during rectal distention. Histological evaluation and the myeloperoxidase activity assay were performed to determine the severity of inflammation. The 5-HT(4) receptor and SERT expression of the ascending colon were monitored using immunohistochemistry and Western blot analyses; the plasma 5-HT levels were measured using an ELISA method. As expected, transient colonic irritation at the neonatal stage led to visceral hypersensitivity, but no mucosal inflammation was later detected during adulthood. Using this model, we found reduced SERT expression (0.298 ± 0.038 vs 0.634 ± 0.200, P < 0.05) and increased 5-HT(4) receptor expression (0.308 ± 0.017 vs 0.298 ± 0.021, P < 0.05). Treatment with fluoxetine (10 mg · kg(-1) · day(-1), days 36-42), tegaserod (1 mg · kg(-1) · day(-1), day 43), or the combination of both, reduced visceral hypersensitivity and plasma 5-HT levels. Fluoxetine treatment increased 5-HT(4) receptor expression (0.322 ± 0.020 vs 0.308 ± 0.017, P < 0.01) but not SERT expression (0.219 ± 0.039 vs 0.298 ± 0.038, P = 0.654). These results indicate that both the 5-HT(4) receptor and SERT play a role in the pathogenesis of visceral hypersensitivity, and its mechanism may be involved in the local 5-HT level.

Effect of the 5-HT4 receptor and serotonin transporter on visceral hypersensitivity in rats

Visceral hypersensitivity plays an important role in motor and sensory abnormalities associated with irritable bowel syndrome, but the underlying mechanisms are not fully understood. The present study was designed to evaluate the expression of the 5-HT4 receptor and the serotonin transporter (SERT) as well as their roles in chronic visceral hypersensitivity using a rat model. Neonatal male Sprague-Dawley rats received intracolonic injections of 0.5% acetic acid (0.3-0.5 mL at different times) between postnatal days 8 and 21 to establish an animal model of visceral hypersensitivity. On day 43, the threshold intensity for a visually identifiable contraction of the abdominal wall and body arching were recorded during rectal distention. Histological evaluation and the myeloperoxidase activity assay were performed to determine the severity of inflammation. The 5-HT4 receptor and SERT expression of the ascending colon were monitored using immunohistochemistry and Western blot analyses; the plasma 5-HT levels were measured using an ELISA method. As expected, transient colonic irritation at the neonatal stage led to visceral hypersensitivity, but no mucosal inflammation was later detected during adulthood. Using this model, we found reduced SERT expression (0.298 ± 0.038 vs 0.634 ± 0.200, P < 0.05) and increased 5-HT4 receptor expression (0.308 ± 0.017 vs 0.298 ± 0.021, P < 0.05). Treatment with fluoxetine (10 mg·kg-1·day-1, days 36-42), tegaserod (1 mg·kg-1·day-1, day 43), or the combination of both, reduced visceral hypersensitivity and plasma 5-HT levels. Fluoxetine treatment increased 5-HT4 receptor expression (0.322 ± 0.020 vs 0.308 ± 0.017, P < 0.01) but not SERT expression (0.219 ± 0.039 vs 0.298 ± 0.038, P = 0.654). These results indicate that both the 5-HT4 receptor and SERT play a role in the pathogenesis of visceral hypersensitivity, and its mechanism may be involved in the local 5-HT level.