[In Vitro and In Vivo Biocompatibility of a Novel, 3-Dimensional Cellulose Matrix Structure]. / In vitro und in vivo Biokompatibilität einer neuartigen, 3-dimensionalen Cellulose-Matrixstruktur.

BACKGROUND: Biological and physical characteristics of matrices are one essential factor in creating bioartificial tissue. In this study, a new 3-dimensional cellulose matrix (Xellulin(®)) was tested in terms of biocompatibility and applicability for tissue engineering in vitro and in vivo. MATERIALS AND METHODS: The tested matrix Xellulin(®) is a natural hydrological gel-matrix containing bacterial cellulose and water. To evaluate the cell biocompatibilty, cell adherence and proliferation characteristics in vitro, the matrix was cultured with human fibroblasts. Further in vivo studies were carried out by transplanting preadipocytes of 4- to 6-week-old Wistar rats with 3 different conditions: a) Xellulin(®) including 500 000 preadipocytes subcutaneous, b) Xellulin(®) including 500 000 preadipocytes within an in vivo bioreactor chamber, c) Xellulin(®) without cells subcutaneous as control. After explantation on day 14 histomorphological and immunohistochemical evaluations were performed. RESULTS: In vitro study revealed an excellent biocompatibility with good cell adherence of the fibroblasts on the matrix and evidence of cell proliferation and creation of a 3-dimensional cell network. In vivo neocapillarisation could be shown in all groups with evidence of erythrocytes (H/E staining) and endothelial vascular cells (RECA-1-staining). A significantly higher vascular density was shown in vascularised bioreactor group (18.4 vessels/100 000 µm(2) (group b) vs. 8.1 (group a), p<0.05). Cell density was the highest in the vascularised group, but without significant values. No immunogenic reaction to the matrix was noticed. DISCUSSION: The promising in vitro results concerning cell adherence and proliferation on the tested matrix could be confirmed in vivo with an evidence of 3-dimensional neocapillarisation. Cell survival was higher in the vascularised group, but without significance. Long-term tests (28-42 days) need to be carried out to evaluate long-term cell survival and the matrix stability. Furthermore, studies concerning the implementation of the matrix within anatomic structures as well as long-term biocompatibility are needed.

Management, clinical outcomes, and complications of acute cannula-related peripheral vein phlebitis of the upper extremity: A retrospective study.

OBJECTIVE: Acute phlebitis due to peripheral vein catheter use is frequently observed in clinical practice, and requires surgical therapy in severe cases. In this retrospective study, we aimed to increase awareness, evaluate current treatment options, and develop recommendations to optimize treatment outcomes. METHODS: A total of 240 hospitalized patients with a diagnosis of upper extremity phlebitis from 2006 to 2011 were evaluated in terms of initial clinical features, parameters, co-morbidities and treatment regimes. Severity of phlebitis was graded according to the Baxter scale by assessing clinical symptoms such as pain, erythema, induration, swelling, or palpable venous cord (grade 0-5). Patients were divided in two subgroups: conservative (n = 132) and operative (n = 108) treatment. RESULTS: Surgical intervention rates and severity were higher for cannula insertion in the cubital fossa region than for cannula insertion in the forearm and hand region (p < 0.05). Baxter scale grades were higher in the surgical treatment group than in the conservative treatment group (4.47 vs. 2.67, respectively). CONCLUSIONS: The cubital fossa region is vulnerable to severe phlebitis and is not recommended as the first site of choice for cannulation. Phlebitis of Baxter scale grade 4 or 5 should be considered for early surgical intervention.

A rare case of massive carpal osteoblastoma requiring complex reconstructive surgery.

An osteoblastoma is a rare, commonly benign, osteoid-producing neoplasm of the bone with an incidence of 2% of all primary bone tumours. We present a case of a 54-year-old patient with persisting carpal pain and massive swelling of the hand for a period of 4 years. Incision biopsies revealed the histopathological finding of a carpal osteoblastoma. After complete tumour excision, including the carpal and, in parts, metacarpal bones, reconstructive surgery was performed with a free osteocutaneous iliac crest flap to obtain a natural hand contour and the best possible hand function. Follow-up revealed improvement of the hand function in terms of flexion, extension and strength without discomfort or further pain. Thus, ongoing carpal pain should lead to an intensive search with further diagnostic measures such as magnetic resonance imaging (MRI) scan as well as biopsies, if necessary, to obtain the correct diagnosis.