Amount and distribution of selected biologically active factors in amniotic membrane depends on the part of amnion and mode of childbirth. Can we predict properties of amnion dressing? A proof-of-concept study.

AIM OF THE STUDY: The amniotic membrane is used as a dressing material, e.g. in ocular surgery or treatment of non-healing wounds. Of note, results of previous studies differ significantly, presumably due to the biological properties of amnion. Some authors suggest that these properties may depend on inter-donor variations, as well as the method of delivery. The aim of our study was to analyse the content of selected factors important for tissue regeneration in various areas of amnion samples originating from elective caesarean sections and on-term natural deliveries. MATERIAL AND METHODS: Cervical and placental samples of amniotic membranes originating from physiological deliveries and caesarean sections have been collected with subsequent preparation of amniotic membrane extracts. The screening of amnion samples was performed using a proteome microarray system. RESULTS: In all of the amnion samples high amounts of angiogenin, IGF-binding proteins-1, -2, and -3, serine protease inhibitor E1, and TIMP-1 were detected. Important variations in the content of these factors were observed between physiological delivery and caesarean section-derived membranes, as well as between placental and cervical portions of the same membrane. CONCLUSIONS: Our study has shown that the content of selected growth factors and regulators of ECM turnover in amniotic membrane samples vary between various donations, and that they depend on the region of the membrane or delivery method. This may determine its potential applications in wound treatment and ophthalmologic surgery. However, our observations require further verification in clinical settings.

Comparison of the paracrine activity of mesenchymal stem cells derived from human umbilical cord, amniotic membrane and adipose tissue.

AIM: The study was conducted to investigate secretory activity and define the paracrine potential of mesenchymal stem cells from human umbilical cord and amniotic membrane (UC-MSCs and AM-MSCs, respectively). METHODS: UC-MSCs (n = 6) were obtained from tissue explants using an adherent method after two weeks of incubation. AM-MSCs (n = 6) were obtained by digestion with tripsin and collagenase. MSC phenotype was confirmed in vitro by performing flow cytometry, differentiation assays and vimentin staining. Supernatants were collected after 48 h culturing in serum-free conditions and the following concentrations were determined: epidermal growth factor (EGF), interleukin (IL)-6, IL-10, tumor necrosis factor-α, transforming growth factor-ß (TGF-ß), vascular endothelial growth factor-α (VEGF-α) and metalloproteinase (MMP) 1, 8 and 13, using multiplex supernatant cytokine assay. Data were compared with adipose tissue derived MSCs (AD-MSCs, n = 6). RESULTS: Both UC-MSC and AM-MSC populations were positively identified as MSCs by flow cytometry and differentiation potential into bone, cartilage and adipose tissue. Using a multiple cytokine detection assay, we proved that both UC-MSCs and AM-MSCs show high secretive capacity. However, the secretion profile differed between cells from various sources. UC-MSCs showed significantly higher production of TGF-ß and lower production of VEGF-α, compared to AD-MSCs (P = 0.004) and AM-MSCs (P = 0.039) and lower levels of EGF (P = 0005). AM-MSCs showed significantly lower levels of MMP-8 than UC-MSCs (P = 0.024); however, there was no difference in levels of released cytokines compared to AD-MSCs. CONCLUSION: AM-MSCs show similar IL production as AD-MSCs, while UC-MSCs have a significantly different profile, which suggests diverse biological potential of both cell types for immunomodulative and regenerative therapy.

Application of IMRT in adjuvant treatment of soft tissue sarcomas of the thigh-Preliminary results.

BACKGROUND: Fracture of the femur is the most frequent late complication in patients with soft tissue sarcomas (STS) who receive external beam radiotherapy after limb-sparing surgery. AIM: To reduce the risk of bone fracture following radiotherapy of STS of the thigh, we minimized the dose to the femur and to surrounding normal tissues by applying intensity modulated radiation therapy (IMRT). We report preliminary results of post-surgery IMRT of the thigh in patients with STS in this extremity. MATERIALS AND METHODS: 10 adult patients undergoing post-operative radiotherapy of STS of the thigh were treated using IMRT. Clinical IMRT plans with simultaneous integrated boost (SIB) and 3-phase three-dimensional conformal radiotherapy (3D-CRT) were designed to adequately treat the planning target volume and to spare the femur to the largest extent possible. Dose distributions and dose-volume histograms were compared. RESULTS: For either technique, a comparable target coverage was achieved; however, target volume was better covered and critical structures were better spared in IMRT plans. Mean and maximum doses to OAR structures were also significantly reduced in the IMRT plans. On average, the mean dose to the femur in 3D-CRT plans was about two times higher than that in IMRT plans. CONCLUSION: Compared with 3D-CRT, the application of IMRT improves the dose distribution within the concave target volumes and reduces dose to the OAR structures without compromising target coverage.

Comparison between intensity modulated radiotherapy (IMRT) and 3D tangential beams technique used in patients with early-stage breast cancer who received breast-conserving therapy.

BACKGROUND: The most often found complications in patients with breast cancer who received radiotherapy are cardiac and pulmonary function disorders and development of second malignancies. AIM: To compare the intensity modulated radiotherapy with the 3D tangential beams technique in respect of dose distribution in target volume and critical organs they generate in patients with early-stage breast cancer who received breast-conserving therapy. MATERIALS AND METHODS: A dosimetric analysis was performed to assess the three radiotherapy techniques used in each of 10 consecutive patients with early-stage breast cancer treated with breast-conserving therapy. Radiotherapy was planned with the use of all the three techniques: 3D tangential beams with electron boost, IMRT with electron boost, and intensity modulated radiotherapy with simultaneous integrated boost. RESULTS: The use of the IMRT techniques enables more homogenous dose distribution in target volume. The range of mean and median dose to the heart and lung was lower with the IMRT techniques in comparison to the 3D tangential beams technique. The range of mean dose to the heart amounted to 0.3-3.5 Gy for the IMRT techniques and 0.4-4.3 for the tangential beams technique. The median dose to the lung on the irradiated side amounted to 4.9-5 Gy for the IMRT techniques and 5.6 Gy for the 3D tangential beams technique. CONCLUSION: The application of the IMRT techniques in radiotherapy patients with early-stage breast cancer allows to obtain more homogenous dose distribution in target volume, while permitting to reduce the dose to critical organs.