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101.
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   
102.
Uremia causes endothelial progenitor cell deficiency   总被引:9,自引:0,他引:9  
BACKGROUND: Circulating bone marrow-derived endothelial progenitor cells (EPCs) promote vascular repair. Their number in peripheral blood correlates with endothelial function and cardiovascular risk in humans. We explored whether uremia influences the number of EPCs. METHODS: We assessed circulating CD34+ hematopoietic progenitor cells in whole blood using flow cytometry and EPCs (in vitro assay) in 46 patients with advanced renal failure and in 46 age- and gender-matched healthy subjects. Further, the effect of uremia on EPC differentiation was studied in vitro and in vivo. RESULTS: Both in renal patients (r= 0.34, P < 0.02) and in healthy subjects (r= 0.32, P= 0.04) the number of EPCs was significantly correlated to the absolute number of CD34+ hematopoietic progenitor cells. Renal patients had significantly fewer EPCs than healthy subjects, however (167 +/- 15 cells/high power field vs. 235 +/- 17 cells/high power field; P < 0.05). Uremic serum significantly (P < 0.05) inhibited EPC differentiation and functional activity in vitro. Amelioration of uremia after institution of renal replacement therapy in patients with terminal renal failure also significantly (P < 0.05) increased the number of EPCs. CONCLUSION: Uremia inhibits differentiation of EPCs. This may impair cardiovascular repair mechanisms in patients with renal failure.  相似文献   
103.
Salvage of a failed Keller resection arthroplasty   总被引:4,自引:0,他引:4  
BACKGROUND: A number of typical complications have been associated with Keller resection arthroplasty. Recurrent valgus deformity, cock-up deformity, and a flail toe may be difficult problems for the treating surgeon because options for salvage are limited. In this study, we evaluated arthrodesis of the first metatarsophalangeal joint as a salvage technique following a failed Keller procedure. In addition, the outcomes of motion-preserving procedures were reviewed in a separate series. METHODS: Arthrodesis of the first metatarsophalangeal joint was performed in twenty-eight patients (twenty-nine feet, group A), and either a repeat Keller procedure or an isolated soft-tissue release was performed in eighteen patients (twenty-one feet, group B). The patients were evaluated at least twenty-four months postoperatively, with a personal interview and a clinical examination with use of a modification of the hallux metatarsal-interphalangeal scale. Radiographs were also made for the group treated with the arthrodesis. RESULTS: In group A, the average duration of follow-up was thirty-six months and fusion was achieved in twenty-six of the twenty-nine feet. Satisfaction was excellent or good in twenty-three cases, and the postoperative score according to the modified hallux metatarsal-interphalangeal scale averaged 76 points (maximum, 90 points). A repeat arthrodesis was necessary in five feet because of malposition or pseudarthrosis. In group B, the average duration of follow-up was seventy-four months. Satisfaction was excellent or good in only six cases, and the patient was dissatisfied in eleven cases. The score according to the modified hallux metatarsal-interphalangeal scale averaged 48 points. Valgus deviation and cock-up deformity had recurred in the majority of the feet at the time of follow-up. CONCLUSIONS: Although it is more technically demanding, we recommend arthrodesis for salvage following a failed Keller procedure since it may be associated with a higher rate of patient satisfaction and better clinical results.  相似文献   
104.
OBJECTIVE: The purpose of this study was to compare mangafodipir trisodium-enhanced MR imaging performed with a phased array coil and contrast-enhanced single-detector helical CT for accuracy in the detection and local staging of pancreatic adenocarcinoma and in the differentiation between cancer and focal pancreatitis. SUBJECTS AND METHODS: Forty-two patients with suspected pancreatic masses underwent contrast-enhanced helical CT and mangafodipir trisodium-enhanced MR imaging at 1.5 T. The images were assessed for the presence or absence of tumors; characterization of masses; and presence of vascular invasion, lymph node metastases, or liver metastases. Imaging findings were correlated with findings at laparotomy, laparoscopy, biopsy, or follow-up. RESULTS: Focal masses were present in 36 patients (cancer, n = 26; focal pancreatitis, n = 7; other, n = 3). The sensitivity for lesion detection of MR imaging was 100% and of CT, 94%. Two small malignant lesions were missed on CT. For the diagnosis of tumor nonresectability, the sensitivity of MR imaging and CT was 90% and 80%, respectively. Liver metastases were missed on MR imaging in one of the eight patients and on CT in four. For differentiation between adenocarcinoma and nonadenocarcinoma, the sensitivity of MR imaging was 100% (positive predictive value, 90%; negative predictive value, 100%), and the sensitivity of CT was 92% (positive predictive value, 80%; negative predictive value, 67%). Receiver operating characteristic analysis revealed that the mean area under the curve for MR imaging was 0.920 and for CT, 0.832 (not significant). CONCLUSION: Mangafodipir trisodium-enhanced MR imaging is as accurate as contrast-enhanced helical CT for the detection and staging of pancreatic cancer but offers improved detection of small pancreatic metastases and of liver metastases compared with CT.  相似文献   
105.
There is some controversy over the treatment of acromioclavicular injuries. The use of the Rockwood classification as the basis for decisions on whether operative or nonoperative treatment is indicated is discussed critically, and the authors' preferred operative technique is described and illustrated by examples. We treat injuries classified according to the Rockwood classification as types I and II with conservative methods. In type III injuries the patient's age, job and free time activities determine whether or not surgery is indicated. In the case of type IV or type VI injuries we always perform temporary internal fixation of the acromioclavicular joint, using transarticular K-wire fixation or hookplate osteosynthesis. Satisfactory results of both operative and nonoperative treatment are reported in the literature. The authors' own results are presented.  相似文献   
106.

Purpose

Excellent long-term results have been reported for implantation of unicompartmental knee arthroplasty (UKA). In many patients the desire for improvement in function often includes an aspiration to return to sports. The purpose of our study was to evaluate physical activities after medial Oxford-III (Biomet) UKA surgery.

Methods

Patients’ physical activity before and after the surgery was assessed using a self reporting questionnaire. We used the Oxford knee scoring system (OKS), the WOMAC-, the Knee society- (KSS) and the UCLA-score to assess postoperative knee function. The mean follow-up was 4.2 years. The female-to-male ratio was 1.3:1. The mean age at surgery was 65.3 years.

Results

Of the 131 patients studied 78 participated in some kind of sports before surgery (mean age 64.4 years), while 53 patients did not perform any sports (mean age 66.5 years) (p > 0.05). At follow-up the patients in the active group were significantly younger than the patients in the inactive group (p < 0.05). The majority of patients (80.1 %) returned to their level of sports activity after UKA surgery. Six patients took up sports after surgery while 15 patients stopped their sports. Among the active patients we found a shift from high- towards low-impact sports. The active patients had significantly higher scores for the OKS, KSS, WOMAC and UCLA score. The complication rate was comparable in both groups.

Conclusion

Our study demonstrates that a high degree of patient satisfaction in terms of sports activity can be achieved using the Oxford-III UKA for medial osteoarthritis.  相似文献   
107.
The remarkable feature of Schwann cells (SCs) to transform into a repair phenotype turned the spotlight on this powerful cell type. SCs provide the regenerative environment for axonal re‐growth after peripheral nerve injury (PNI) and play a vital role in differentiation of neuroblastic tumors into a benign subtype of neuroblastoma, a tumor originating from neural crest‐derived neuroblasts. Hence, understanding their mode‐of‐action is of utmost interest for new approaches in regenerative medicine, but also for neuroblastoma therapy. However, literature on human SCs is scarce and it is unknown to which extent human SC cultures reflect the SC repair phenotype developing after PNI in patients. We performed high‐resolution proteome profiling and RNA‐sequencing on highly enriched human SC and fibroblast cultures, control and ex vivo degenerated nerve explants to identify novel molecules and functional processes active in repair SCs. In fact, we found cultured SCs and degenerated nerves to share a similar repair SC‐associated expression signature, including the upregulation of JUN, as well as two prominent functions, i.e., myelin debris clearance and antigen presentation via MHCII. In addition to myelin degradation, cultured SCs were capable of actively taking up cell‐extrinsic components in functional phagocytosis and co‐cultivation assays. Moreover, in cultured SCs and degenerated nerve tissue MHCII was upregulated at the cellular level along with high expression of chemoattractants and co‐inhibitory rather than ‐stimulatory molecules. These results demonstrate human SC cultures to execute an inherent program of nerve repair and support two novel repair SC functions, debris clearance via phagocytosis‐related mechanisms and type II immune‐regulation. GLIA 2016;64:2133–2153  相似文献   
108.

Background

Despite the increased risk of hemorrhage and deteriorating neurological function of once-bled cerebral cavernous malformations (CM), the management of eloquently located CMs remains controversial.

Methods

All eloquently located CMs (n?=?45) surgically treated between 03/2006 and 04/2011 in our department were consecutively evaluated. Eloquence was characterized according to Spetzler and Martin's definition. The following locations were approached: brainstem, n?=?16; sensorimotor, n?=?8; visual pathway, n?=?7; cerebellum (deep nuclei and peduncles), n?=?7; basal ganglia, n?=?4, and language, n?=?3. Follow-up data was available for 41 patients (91 %) with a median interval of 14 months. Outcomes were evaluated according to the Glasgow outcome and the modified Rankin scale.

Results

Immediately after surgery, 47 % (n?=?21) had a new deficit. At follow-up, 80 % (n?=?36) recovered to at least preoperative status or were better than before surgery, 9 % (n?=?4) exhibited a slight, and 7 % (n?=?3) had a moderate neurological impairment. Only two cases (4 %) with a new permanent severe deficit were observed, both related to dorsal brainstem surgery. The outcome after the surgery of otherwise located brainstem CMs was as beneficial as that for non-brainstem CMs. Patients with initially poor neurological performance fared worse than oligosymptomatic patients.

Conclusions

Despite the high postoperative transient morbidity, the majority improved profoundly during follow-ups. Compared with natural history, surgical treatment should be considered for all eloquent symptomatic CMs. Dorsal brainstem location and poor preoperative neurological status are associated with an increased postoperative morbidity.
  相似文献   
109.
ABSTRACT: BACKGROUND: Outcome measurement in shoulder surgery is essential to evaluate the patient safety and treatment efficiency. Currently this is jeopardized by the fact that most patient-reported selfassessment instruments are not comparable. Hence, the aim was to develop a reliable selfassessment questionnaire which allows an easy follow-up of patients. The questionnaire also allows the calculation of 3 well established scoring systems, i.e. the Shoulder Pain and Disability Index (SPADI), the Constant-Murley Score (CMS), and the Disabilities of the Arm, Shoulder and Hand (DASH) Score. The subjective and objective items of these three systems were condensed into a single 30-questions form and validated against the original questionnaires. METHODS: A representative collective of patients of our shoulder clinic was asked to fill in the newly designed self-assessment Munich Shoulder Questionnaire (MSQ). At the same time, the established questionnaires for self-assessment of CONSTANT, SPADI and DASH scores were handed out. The obtained results were compared by linear regression analysis. RESULTS: Fifty one patients completed all questionnaires. The correlation coefficients of the results were r = 0.91 for the SPADI, r = -0.93 for the DASH and r = 0.94 for the CMS scoring system, respectively. CONCLUSIONS: We developed an instrument which allows a quantitative self-assessment of shoulder function. It provides compatible data sets for the three most popular shoulder function scoring systems by one single, short 30-item. This instrument can be used by shoulder surgeons to effectively monitor the outcome, safety and quality of their treatment and also compare the results to published data in the literature.  相似文献   
110.
Objectives: Artificial colloids, frequently used to prevent hemorrhagic shock in children, impair blood coagulation. To determine the impact of acute isovolaemic hemodilution with artificial colloids on clot formation, we conducted an experimental study in a pediatric animal model. Methods: Fifteen piglets underwent hemorrhage by withdrawing 40 ml·kg?1 of blood volume in steps of 10 ml·kg?1 each within 1 hour. After each withdrawal, the blood loss was randomly compensated by administering 4% gelatin (GEL) or hydroxylethyl starch 130/0.42 (HES) in a ratio of 1 : 1, or isotonic crystalloid solution (ICS) in a ratio of 1 : 4 for isovolaemic hemodilution. Quality of clot formation and platelet function was measured using Thrombelastometry (ROTEM®) and Multiple electrode impedance aggregometry (Multiplate®) after 10, 20, and 40 ml·kg?1 blood replacement. Results: Moderate hemodilution (10–20 ml·kg?1 blood replacement) caused no significant differences among groups (e.g. INTEM®‐MCF after 20 ml·kg?1 blood replacement (ICS vs GEL vs HES, P > 0.05). Profound hemodilution with 40 ml·kg?1 blood replacement showed a significant difference between ICS and both colloids (P < 0.05), but no significant differences between GEL and HES. Conclusions: Impairment of clot formation by moderate isovolaemic hemodilution did not significantly differ between ICS, GEL, and HES. Profound hemodilution of more than 50% of the estimated blood volume with GEL and HES caused significant impairment of clot formation in comparison to ICS and has to be considered when using high amounts of these synthetic colloids.  相似文献   
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