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61.
BACKGROUND: Bile duct injury after hepatic artery thrombosis (HAT) in liver transplantation is believed to be caused by ischemia predominantly. We aimed to define the involvement of bile secretory dysfunction in the pathogenesis of liver injury after HAT. METHODS: In a murine model, the main hepatic artery, the extrahepatic peribiliary plexus, or both arterial connections to the liver were interrupted (n=5 for each group). After 1, 14, or 28 days, hepatobiliary function was assessed by analysis of bile transporter expression, serum bile acids and bilirubin, and hepatic ATP content. In addition, cellular injury was assessed by light microscopy and biochemical markers. RESULTS: There were no signs of hepatobiliary dysfunction or injury in sham-operated animals or in mice with interruption of the hepatic artery or the extrahepatic peribiliary plexus alone. However, as early as 24 hr after complete dearterialization, bile transporter expression was significantly reduced and intrahepatic cholestasis started to progress the following weeks. Histologic studies at 28 days after complete dearterialization showed severe hepatobiliary injury. CONCLUSIONS: This study indicates that arterial blood supply is critical for normal bile secretion. Bile duct injury after complete arterial deprivation is preceded by a loss of bile secretory function and subsequent intrahepatic cholestasis.  相似文献   
62.
A graded forceps crush spinal cord injury model in mice   总被引:1,自引:0,他引:1  
Given the rising availability and use of genetically modified animals in basic science research, it has become increasingly important to develop clinically relevant models for spinal cord injury (SCI) for use in mice. We developed a graded forceps crush model of SCI in mice that uses three different forceps with spacers of 0.25, 0.4, and 0.55 mm, to produce severe, moderate, and mild injuries, respectively. Briefly, each mouse was subjected to laminectomy of T5-T7, 15-second spinal cord crush using one of those forceps, behavioral assessments, and post-mortem neuroanatomical analyses. There were significant differences among the three injury severity groups on behavioral measures (Basso Mouse Score, footprint, and ladder analyses), demonstrating an increase in neurological deficits for groups with greater injury severity. Quantitative analysis of the lesion demonstrated that as injury severity increased, lesion size and GFAP negative area increased, and spared tissue, spinal cord cross-sectional area, spared grey matter and spared white matter decreased. These measures strongly correlated with the behavioral outcomes. Similar to other studies of SCI in mice, we report a dense laminin and fibronectin positive extracellular matrix in the lesion sites of injured mice, but unlike those previous studies, we also report the presence of numerous p75 positive Schwann cells in and around the lesion epicenter. These results provide evidence that the graded forceps crush model is an attractive alternative for the study of SCI and related therapeutic interventions. Because of its demonstrated consistency, ease of use, low cost, and clinical relevance, this graded forceps crush is an attractive alternative to the other mouse models of SCI currently available.  相似文献   
63.
BACKGROUND: Paralytic pes calcaneus is commonly associated with myelomeningocele and continues to be one of the most difficult deformities to treat. The purpose of the present study is to describe and report the preliminary results of a new procedure to dynamically correct paralytic pes calcaneus. MATERIALS AND METHODS: Since 2002, the senior surgeon operated on six patients with myelomeningocele and developed a new procedure to dynamically correct paralytic pes calcaneus. This new procedure combines a complete tendon transfer (tibialis anterior and posterior, peroneus brevis and longus, and extensor digitorum and hallucis longus) to the Achilles tendon and an additive triple arthrodesis. The extent of the calcaneus deformity was evaluated by measuring the talocalcaneal angle. The mean followup was 32 months. RESULTS: Excellent results were achieved in five of the six patients with a mean age of 17.5 years. Using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot scale, pain and function improved from an average of 41.6 preoperatively to 72.0 postoperatively. The deformity as assessed by the talocalcaneal angle, the calcaneal pitch, and the talometatarsal I angle improved after surgery significantly (p < 0.004). After 12 months, an additional surgery was required in two patients due to disabling drop-foot. CONCLUSION: This new surgical technique to correct paralytic pes calcaneus including complete tendon transfer and triple arthrodesis is promising. Although this is a technically demanding procedure, it provides an excellent functional result without the residual complications associated with ankle arthrodesis.  相似文献   
64.
Background and aims Occurrence of tumor relapse is frequent in patients with pancreatic cancer despite the absence of residual tumor detectable at primary surgery and in histopathological examination. Therefore, it has to be assumed that current tumor staging procedures fail to identify minimal amounts of disseminated tumor cells, which might be precursors of subsequent metastatic relapse. The aim of this study was to assess the prognostic impact of minimal tumor cell spread detected in lymph nodes classified as “tumor-free” in routine histopathologic evaluation. Materials and methods A total of 154 “tumor-free” lymph nodes from 59 patients with pancreatic cancer who underwent intentionally curative tumor resection were examined by immunohistochemistry for disseminated tumor cells. Results Fifty (32.5%) of the “tumor-free” lymph nodes obtained from 36 (61%) patients displayed disseminated tumor cells. Multivariate survival analysis revealed that the presence of disseminated tumor cells in “tumor-free” lymph nodes is an independent prognostic factor for both a significantly reduced relapse-free survival (p = 0.03) and overall survival (p = 0.02). Conclusions The frequent occurrence and prognostic impact of immunohistochemically identifiable disseminated tumor cells in lymph nodes of patients with operable pancreatic cancer supports the need for a refined staging system of excised lymph nodes, which should include immunohistochemical examination.  相似文献   
65.
To determine and compare the influence of 2 different approaches on quadriceps femoris muscle function in total knee arthroplasty (TKA), 20 patients (14 women, 6 men) with bilateral knee osteoarthritis underwent a 1-stage bilateral TKA. Surgical approaches (subvastus, midvastus) were performed by a random selection. Measurements of quadriceps voluntary activation and maximal voluntary contraction were estimated by a twitch interpolation technique before, 3 and 6 months after TKA. Knee pain was quantified by the Lewis Score. There was no difference between the 2 approaches at 3 and 6 months after TKA with regard to maximal voluntary contraction (P = 0.84, F = 0.041) and voluntary activation (P = .863, F = 0.031). In the subvastus group was a significantly higher knee pain until 6 months after surgery (P = .02). The subvastus approach for TKA does not provide any advantages compared with the midvastus approach with respect to the quadriceps femoris muscle strength in the early postoperative period. Furthermore, the subvastus approach caused significantly more pain postoperatively.  相似文献   
66.

Background

Hypocalcemia and nerve injury are the most severe complications after thyroid surgery. The duration of surgery has not been previously considered as a risk factor for postoperative complications in patients undergoing total thyroidectomy. We sort to investigate the influence of prolonged surgery on postoperative complications in patients undergoing total thyroidectomy.

Methods

We hypothesized that a threshold of?>?120 minutes of surgical time could represent a surrogate marker for postoperative complications in patients undergoing total thyroidectomy for benign thyroid disorders. The study population was divided into two groups based on the median duration of surgery (120 min): group I?≤?120 minutes (control group), group II?>?120 minutes (study group). The charts of eligible patients undergoing total thyroidectomy within a six-year period from January 1st 2006 to December 31st 2012 were reviewed. The primary outcomes included the rates postoperative hypocalcemia and recurrent laryngeal nerve palsy. The secondary outcomes included the rates of postoperative hemorrhage, wound dehiscence and length of hospital stay.

Results

305 cases of thyroidectomy were included for analysis; 130 (42.6%) control group and 175 (57.4%) study group. Transient (15.4% vs 19.4%) and permanent (3.8% vs. 2.9%) hypocalcemia were recorded in control and study group respectively. The incidence of nerve palsy was 1.5% in the control group and 1.4% in the study group. The mean length of postoperative hospital stay was 3d in both groups. There was no significant difference amongst both groups with regard to postoperative bleeding (p?=?0.57) and wound dehiscence (p?=?0.31). Prolonged surgery (> 120 min) was not identified as a risk factor for increased postoperative complication.

Conclusion

Prolonged duration of surgery?>?120 minutes is not a surrogate marker for postoperative complications in patients undergoing total thyroidectomy.
  相似文献   
67.
Cold atmospheric plasma has already been shown to decrease the bacterial load in chronic wounds. However, until now it is not yet known if plasma treatment can also improve wound healing. We aimed to assess the impact of cold atmospheric argon plasma on the process of donor site healing. Forty patients with skin graft donor sites on the upper leg were enrolled in our study. The wound sites were divided into two equally sized areas that were randomly assigned to receive either plasma treatment or placebo (argon gas) for 2 minutes. Donor site healing was evaluated independently by two blinded dermatologists, who compared the wound areas with regard to reepithelialization, blood crusts, fibrin layers, and wound surroundings. From the second treatment day onwards, donor site wound areas treated with plasma (n = 34) showed significantly improved healing compared with placebo‐treated areas (day 1, p = 0.25; day 2, p = 0.011; day 3, p < 0.001; day 4, p < 0.001; day 5, p = 0.004; day 6, p = 0.008; day 7, p = 0.031). Positive effects were observed in terms of improved reepithelialization and fewer fibrin layers and blood crusts, whereas wound surroundings were always normal, independent of the type of treatment. Wound infection did not occur in any of the patients, and no relevant side effects were observed. Both types of treatment were well tolerated. The mechanisms contributing to these clinically observed effects should be further investigated.  相似文献   
68.
PURPOSE: Important criteria for optimized stent implantation are high radial force and complete apposition of the stent itself. The aim of this study was to develop a simple method to assess these parameters under controlled experimental conditions and to compare vascular stents of different designs with regard to these parameters. MATERIALS AND METHODS: Five balloon-expandable stents of different designs (Jostent Flex, MAC stent, ML-Tristar, ML-Ultra, and S670) were tested. Fourteen stents of each type were implanted in a curved plastic vessel model (curve radius, 10 mm; lumen diameter, 3.5 mm) with use of a balloon inflation pressure of 12 atm. Part of the model was a nonflexible eccentric stenosis which was 2 mm or 8 mm in length. After stent implantation, a stenosis of 10%-70% was induced and radial force of the stent struts was measured at the site of the stenosis. The apposition of the stent to the vessel wall was imaged by high-resolution radiography. RESULTS: Analysis of variance showed significant differences of radial force between the tested stents (P <.001). The ML-Tristar and ML-Ultra stents had the highest radial force with maximum mean values of 687 cN and 846 cN at a stenosis of 70% in the model with the long stenosis. The radial force of the S670 stent was the lowest whereas the MAC stents showed an intermediate radial force. Radial force of the ML-Ultra stent was as much as 3.8 times higher than the force of the S670 stent (P <.001). Fifty percent of the ML-Tristar and ML-Ultra stents did not expand sufficiently to touch the vessel surface at the outer curvature. With an inflation pressure of 17 atm, complete apposition of these stents was achieved. The highest number of apposition irregularities was found in the S670 group (13 of 14 stents), whereas the MAC stents revealed the lowest number of irregular appositions (three of 14 stents). A significant correlation was found between the number of interconnecting struts and the number of irregular apposition events (P <.01). CONCLUSIONS: This model allows an accurate in vitro evaluation of different stent parameters, such as apposition to the vessel wall and radial force. None of the investigated stents showed optimal results with respect to both parameters. The apposition behavior was significantly influenced by the architecture of the stents.  相似文献   
69.
Human Papillomaviruses in Transplant-Associated Skin Cancers   总被引:1,自引:0,他引:1  
Eggert Stockfleth  MD    Ingo Nindl  Ph  D  Wolfram Sterry  MD    Claas Ulrich  MD    Tobias Schmook  MD    Thomas Meyer  Ph  D 《Dermatologic surgery》2004,30(4P2):604-609
Background. Human papillomavirus (HPV) infection has been suggested to be involved in the development of nonmelanoma skin cancer, the most common malignancy after solid-organ transplantation.
Objective. The objective of this study was to analyze the prevalence of different HPV types in squamous cell carcinomas (SCC) and basal cell carcinomas (BCC) of transplant recipients and nonimmunosuppressed patients.
Methods. To include the complete spectrum of HPV types in skin lesions, a comprehensive polymerase chain reaction assay with five different primer combinations was used.
Results. For SCC, HPV DNA was detected more frequently in tumors of transplant recipients (12/16, 75%) than of nonimmunosuppressed patients (7/19, 37%). In contrast, the HPV detection rate was similar in BCC specimens (4/8 or 50% in transplanted patients; 27/56 or 48% in nonimmunosupressed patients). Overall, 22 different HPV types were identified. HPV types 5 and 8 were detected predominately in SCC from transplant recipients. The amount of viral DNA was slightly higher in SCC of transplanted than in nonimmunosuppressed patients, but much lower than in both cutaneous and genital warts.
Conclusions. Cutaneous infections with HPV5 and HPV8 may represent an increased risk for SCC development in transplant recipients. The mechanisms by which these viruses may contribute to skin cancer development still remain unclear.  相似文献   
70.
We analyzed the histologic features of peripheral nerve sheath tumors occurring in 14 patients with schwannomatosis. Among a total of 31 tumors, 19 tumors (61%) showed schwannoma-like nodules within a neurofibroma-like tumor, corresponding to hybrid neurofibroma/schwannoma. At least 1 hybrid tumor occurred in 10 of 14 (71%) schwannomatosis patients. We then retrieved cases of hybrid tumors without documented relation to schwannomatosis from our database and identified 41 tumors arising in 23 patients. More than half of these patients (14/23) were reported to suffer from multiple peripheral nerve sheath tumors, favoring a tumor syndrome. Indeed, analysis of clinical records revealed the diagnosis of neurofibromatosis type 2 (NF2) in 26% (6/23), neurofibromatosis type 1 (NF1) in 9% (2/23), definite schwannomatosis in 4% (1/23), and possible schwannomatosis in 13% (3/23) of patients with multiple nerve sheath tumors. Our findings suggest that hybrid neurofibroma/schwannoma represents a common tumor type in schwannomatosis and shows a striking association with neurofibromatoses.  相似文献   
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