Yohei Sotsuka

Growth Factor Measurement and Histological Analysis in Platelet Rich Fibrin: A Pilot Study

ObjectiveThe aim of this study was to compare growth factor amount contained in platelet rich fibrin (PRF) and compare with that in platelet rich plasma (PRP), and in whole blood. And also to investigate distribution of growth factors and cellular components in PRF.Materials and MethodsPRF and PRP were obtained from the same sample of peripheral blood. Extraction of proteins were done with lysis buffer, accompanied by freeze and thaw procedures. Concentration of two representative growth factors in platelets: platelet derived growth factor (PDGF) and transforming growth factor beta (TGF-β), were measured with enzyme-linked immunosorbent assay (ELISA). PRF was cut into three parts: (top, middle and bottom), and growth factor concentration was measured respectively. Paraffin embedded section of PRF was observed with Giemsa stain. Immuno-histochemical analysis with anti-PDGF and anti-TGF-β antibodies was also conducted.ResultsThe growth factor levels in PRF was higher than in peripheral blood and comparable to those in PRP. Growth factor levels in bottom part of PRF was much higher than in top and middle part. Microscopically, platelets and mono-nucleated cells were concentrated just above the yellow–red interface. Poly-nucleated cells were concentrated below the interface.ConclusionThe growth factors were surely concentrated in PRF. This result can support basis of good clinical outcomes. For effective application of PRF, the knowledge that growth factors and cells are not equally distributed in PRF should be utilized.

Hypertrophic scar contracture is mediated by the TRPC3 mechanical force transducer via NFkB activation

Wound healing process is a complex and highly orchestrated process that ultimately results in the formation of scar tissue. Hypertrophic scar contracture is considered to be a pathologic and exaggerated wound healing response that is known to be triggered by repetitive mechanical forces. We now show that Transient Receptor Potential (TRP) C3 regulates the expression of fibronectin, a key regulatory molecule involved in the wound healing process, in response to mechanical strain via the NFkB pathway. TRPC3 is highly expressed in human hypertrophic scar tissue and mechanical stimuli are known to upregulate TRPC3 expression in human skin fibroblasts in vitro. TRPC3 overexpressing fibroblasts subjected to repetitive stretching forces showed robust expression levels of fibronectin. Furthermore, mechanical stretching of TRPC3 overexpressing fibroblasts induced the activation of nuclear factor-kappa B (NFκB), a regulator fibronectin expression, which was able to be attenuated by pharmacologic blockade of either TRPC3 or NFκB. Finally, transplantation of TRPC3 overexpressing fibroblasts into mice promoted wound contraction and increased fibronectin levels in vivo. These observations demonstrate that mechanical stretching drives fibronectin expression via the TRPC3-NFkB axis, leading to intractable wound contracture. This model explains how mechanical strain on cutaneous wounds might contribute to pathologic scarring.

Influence of continuous or intermittent negative pressure on bacterial proliferation potency in vitro.

Abstract Negative pressure wound therapy is helpful and effective in the treatment of intractable skin ulcers and defects, not only acute wounds. However, application of negative pressure wound therapy for an infected wound is still controversial. The authors developed an in-vitro model of negative pressure wound therapy and investigated the influence of various types of negative pressure environment on the proliferation potency of non-pathogenic Escherichia coli. E. coli in Luria-Bertani liquid media was cultured at 37°C under different environments, which were normal atmosphere in group 1, continuous negative pressure of 75 mmHg in group 2, intermittent negative pressure of 75 mmHg with cycle time of 1 minute aspiration and 1 minute abeyance in group 3, with the one of 3 minutes aspiration and 3 minutes abeyance in group 4. The relative amounts of E. coli in each group were investigated at different times. The proliferation potency of E. coli was higher under negative pressure than under normal atmosphere; higher under intermittent negative pressure than under continuous negative pressure; and higher under intermittent negative pressure with a short cycle than with a long cycle. It is important to consider the possibility that the intermittent and continuous mode of negative pressure wound therapy may promote proliferation of bacteria in an infected wound with no blood flow like necrotic tissue.

Immediate reconstruction using free medial circumflex femoral artery perforator flaps after breast-conserving surgery

Recent advances in perforator flap surgical techniques have allowed for safe and reliable autologous tissue transfer with minimal donor-site morbidity. Between April 2012 and January 2013, we performed immediate breast reconstruction using free medial circumflex femoral artery perforator (MCFAP) flaps in 15 patients after breast-conserving surgery. The flaps were harvested from patients in the lithotomy position, while a second surgical team simultaneously conducted tumour resection. Of the 15 procedures performed, three flaps were dissected as true perforator flaps, while 12 flaps were dissected as muscle-sparing perforator flaps. The mean flap weight was 138.5 g (range, 77-230 g) and the mean pedicle length was 5.7 cm (range, 3.0-9.0 cm). Recipient vessels for anastomosis were serratus branches in 10 patients, internal mammary vessels in three patients and thoracodorsal vessels in two patients. The mean duration of surgery was 6.74 h (range, 5.65-9.45 h). There were no major complications requiring surgical intervention. Researchers observed partial flap necrosis, which manifested as small firm lesions in two patients, as well as local wound infection and dehiscence in one patient, which resolved spontaneously. There were no instances of donor-site seroma formation or lymphoedema in any of the patients. An objective assessment of postoperative photographs showed that cosmetic results were mostly satisfactory. Donor-site scars along the medial groin crease were inconspicuous and readily concealed by clothing. Given its reliable vascularity and minimal donor-site morbidity, the free MCFAP flap can be a good alternative for partial breast reconstruction after breast-conserving surgery.

Volume of deep inferior epigastric perforator flap quantified preoperatively by using 64-multidetector-row computed tomography

flap with the Becker 35 expandable implant. Journal of Plastic, Reconstructive & Aesthetic Surgery: JPRAS 2012;65(6):705e10. 2. Gran MV, Nicholson S, Mahajan AL. Pectoralis fascia grafts in breast reconstruction. Journal of Plastic, Reconstructive & Aesthetic Surgery: JPRAS 2012;65(4):e104e5. 3. Graf RM, Bernardes A, Rippel R, Araujo LR, Damasio RC, Auersvald A. Subfascial breast implant: a new procedure. Plastic and Reconstructive Surgery 2003;111(2):904e8. 4. Spear SL, Parikh PM, Reisin E, Menon NG. Acellular dermisassisted breast reconstruction. Aesthetic Plastic Surgery 2008; 32(3):418e25. 5. Breuing KH, Warren SM. Immediate bilateral breast reconstruction with implants and inferolateral AlloDerm slings. Annals of Plastic Surgery 2005;55(3):232e9.

An augmented reality system in lymphatico-venous anastomosis surgery

Indocyanine green lymphography, displayed as infrared image, is very useful in identifying lymphatic vessels during surgeries. Surgeons refer the infrared image on the displays as they proceed the operation. Those displays are usually placed on the walls or besides the operation tables. The surgeons cannot watch the infrared image and the operation field simultaneously. They have to move their heads and visual lines. An augmented reality system was developed for simultaneous referring of the infrared image, overlaid on real operation field view. A surgeon wore a see-through eye-glasses type display during lymphatico-venous anastomosis surgery. Infrared image was transferred wirelessly to the display. The surgeon was able to recognize fluorescently shining lymphatic vessels projected on the glasses and dissect them out.

Bilateral Maxillary Reconstruction Using Fibular Flap in Bisphosphonate-related Osteonecrosis.

Summary: Recent reports have shown successful transfer of vascularized fibular flap in bisphosphonate-induced mandibular osteonecrosis. We present a case of a 50-year-old patient who presented with bisphosphonate-related osteonecrosis of bilateral maxilla, which is reconstructed using a fibular flap.

Image Overlay of Deep Inferior Epigastric Artery in Breast Reconstruction

We applied those tech-nologies to preoperative planning of breast recon-struction and describe a quicker-to-perform method of marking perforators on real patient’s abdominal skin before surgery by using image overlay technique.CTA studies were prospectively performed in pa-tients before undergoing breast reconstructive surgery, using 64-multidetector computed tomography scanner (Siemens Healthcare SOMATOM Definition AS+, Sie-mens Japan, Japan). A MacBook Air 1.7 GHz dual-core Intel Core i7 Processor was used, and axial source DI-COM data were transferred to OsiriX (Pixmeo, Geneva, Switzerland), a free, open-source medical application (available for only MacOS X) to convert into maximum intensity projection image in coronal plane (Fig. 1). The

A new rabbit model of impaired wound healing in an X-ray-irradiated field

Radiation is an important therapy for cancer with many benefits; however, its side effects, such as impaired wound healing, are a major problem. While many attempts have been made to overcome this particular disadvantage, there are few effective treatments for impaired wound healing in an X-ray-irradiated field. One reason for this deficiency is the lack of experimental models, especially animal models. We have previously reported a mouse model of impaired wound healing in which the irradiation area was restricted to the hindlimbs. In this mouse model, due to the size of the animal, a diameter of five millimeters was considered the largest wound size suitable for the model. In addition, the transplanted cells had to be harvested from other inbred animals. To investigate larger wounds and the impact of autologous specimen delivery, a rabbit model was developed. Rabbits were kept in a special apparatus to shield the body and hindlimbs while the irradiation field was exposed to radiation. Six weeks after irradiation, a 2 x 2 cm, full-thickness skin defect was made inside the irradiation field. Then, the wound area was observed over time. The wound area after irradiation was larger than that without irradiation at all time points. Both angiogenesis and collagen formation were reduced. For further study, as an example of using this model, the effect of autologous platelet-rich plasma (PRP) was observed. Autologous PRP from peripheral blood (pb-PRP) and bone marrow aspirate (bm-PRP) was processed and injected into the wounds in the irradiated field. Two weeks later, the wounds treated with bm-PRP were significantly smaller than those treated with phosphate buffer vehicle controls. In contrast, the wounds treated with pb-PRP were not significantly different from the controls. This rabbit model is useful for investigating the mechanism of impaired wound healing in an X-ray-irradiated field.

Free flap transfer reconstruction in managing tongue carcinoma during pregnancy

Abstract Malignant oral cancers do not commonly occur in pregnant women. But when they do, the presence of a foetus and maternal physiological changes complicate and limit the treatment options. Risk benefit assessment and balancing of them are always important. A 33-year-old woman, who was 25 weeks pregnant, presented with a squamous cell carcinoma on her tongue. She was clinically staged II (T2, N0 and M0). Discussions between the patient, surgical teams and obstetricians agreed to continue her pregnancy while managing the tumour. Hemi-glossectomy and ipsilateral neck dissection was performed. Free antero-lateral thigh flap was transferred to reconstruct the tongue defect, successfully. The patient gave birth to a healthy baby afterward. She is tumour free for 6 years. Free flap reconstruction can be an option, even if the patient is pregnant.