吉村 浩太郎

BACKGROUND: Clinical sequelae of irradiation result in tissue devitalization (e.g., ischemia, fibrosis, and atrophy) where wound healing capacity is impaired. Fat-derived products may work to treat such pathology. METHODS: Nonlethal irradiation at various doses (5, 10, and 15 Gy) and frequencies (one to three times on sequential days) was delivered to dorsal skin of nude mice, and subsequent gross and microscopic changes were evaluated for up to 4 weeks. Cutaneous punch wounds were then created to compare wound healing in irradiated and nonirradiated states. Wounds were also locally injected with vehicle, cultured adipose-derived stem cells, centrifuged fat tissue, or micronized cellular adipose matrix, and the therapeutic impact was monitored for up to 15 days. RESULTS: Nude mice given total doses greater than 15 Gy spontaneously developed skin ulcers, and radiation damage was dose-dependent; however, a fractionated irradiation protocol was able to reduce the damage. Histologic assessment revealed dose-dependent dermal fibrosis/thickening and subcutaneous atrophy. Dose-dependent (5 to 15 Gy) impairment of wound healing was also evident. At the highest dosage (15 Gy three times), open wounds persisted on day 15. However, wounds injected with cultured adipose-derived stem cells were nearly healed on day 12, and those treated with injection of centrifuged fat or micronized tissue healed faster than untreated controls (p < 0.05). There was no significant differences between treated groups. CONCLUSIONS: Tissue devitalization by irradiation was dose-dependent, although fractionated protocols helped to reduce it. Adipose-derived stem cells and other fat-derived products harboring adipose-derived stem cells successfully revitalized irradiated tissues and accelerated wound healing.

Chronic changes following radiotherapy include alterations in tissue-resident stem cells and vasculatures, which can lead to impaired wound healing. In this study, novel recombinant human collagen peptide (rhCP) scaffolds were evaluated as a biomaterial carrier for cellular regenerative therapy. Human adipose-derived stem cells (hASCs) were successfully cultured on rhCP scaffolds. By hASC culture on rhCP, microarray assay indicated that expression of genes related to cell proliferation and extracellular matrix production was upregulated. Pathway analyses revealed that signaling pathways related to inflammatory suppression and cell growth promotion were activated as well as signaling pathways consistent with some growth factors including vascular endothelial growth factor, hepatocyte growth factor, and transforming growth factor beta, although gene expression of these growth factors was not upregulated. These findings suggest the rhCP scaffold showed similar biological actions to cytokines regulating cell growth and immunity. In subsequent impaired wound healing experiments using a locally irradiated (20 Gray) mouse, wound treatment with rhCP sponges combined with cultured hASCs and human umbilical vein endothelial cells accelerated wound closure compared with wounds treated with rhCP with hASCs alone, rhCP only, and control (dressing alone), with better healing observed according to this order. These results indicating the therapeutic value of rhCP scaffolds as a topical biomaterial dressing and a biocarrier of stem cells and vascular endothelial cells for regenerating therapies. The combination of rhCP and functional cells was suggested to be a potential tool for revitalizing stem cell-depleted conditions such as radiation tissue damage.

BACKGROUND: Fat grafting frequently requires multiple treatments and thus repeated liposuction to achieve treatment goals. The purpose of this study was to evaluate whether cryopreservation of adipose tissue may facilitate future fat grafting. METHODS: Lipoaspirates were harvested from six women and preserved using two cryopreservation methods: (1) simple cooling to -80°C (cryo-1); or (2) programmed cooling to -196°C (cryo-2). Fresh fat, cryo-1 fat, and cryo-2 fat were analyzed both in vitro and in vivo. RESULTS: Immunohistochemistry of both types of cryopreserved adipose tissue revealed that most adipocytes were necrotic. The cell number and viability of stromal vascular fraction cells were significantly decreased in cryo-1 fat (1.7 × 10 cells, 42.6 percent viable) and cryo-2 fat (2.0 × 10 cells, 55.4 percent viable), compared with fresh fat (3.9 × 10 cells, 90.6 percent viable). Although adipose-derived stem cells were cultured successfully from all fats, functional adipose-derived stem cells from cryopreserved fats were much fewer, with comparable multilineage differentiating capacity. In vivo studies using human fat grafted into immunocompromised mice revealed that, 3 months after transplantation, all of the cryopreserved fats maintained their volume to some extent; however, the cryopreserved fats were mostly filled with dead tissue and produced significantly lower engraftment scores than fresh fat. CONCLUSIONS: Most adipocytes were killed in the process of cryopreservation and thawing. Adipose-derived stem cells were isolated from cryopreserved fat, but the number of functional adipose-derived stem cells was very limited in both cryopreservation methods. After grafting, cryopreserved fat was retained as dead and fibrous tissue, suggesting a risk of clinical complications such as oil cysts.

BACKGROUND:There is no standard method to ensure survival of random-pattern skin flaps. The authors developed a rat anemia model to observe survival of random-pattern skin flaps after blood transfusion and hemodilution.;METHODS:Anemia was induced by withdrawal of 35 percent blood volume followed by compensation with the same amount of blood (blood transfusion model) or plasma equivalent (normovole

:Immediate reconstruction of orbitomaxillary defects is challenging for head and neck reconstructive surgeons. The primary goals of orbitomaxillary reconstruction are to cover the skin and mucosal defects, fill the defect space, and reconstruct the natural facial contour. This report describes 2 patients who underwent extended orbitomaxillectomy and immediate reconstruction using a combined latiss

BACKGROUND:Condensation of grafted fat has been considered a key for achieving better outcomes after fat grafting. The authors investigated the therapeutic potential of two mechanical tissue micronizing procedures: squeeze and emulsification.;METHODS:Human aspirated fat was centrifuged (centrifuged fat) and fragmented with an automated slicer (squeezed fat). Alternatively, centrifuged fat was emul

:For chronic wounds, the delivery of stem cells in spheroidal structures can enhance graft survival and stem cell potency. We describe an easy method for the 3D culture of adipose-derived stem/stromal cells (ASCs) to prepare a ready-to-use injectable. We transferred suspensions of monolayer-cultured ASCs to a syringe containing hyaluronic acid (HA) gel, and then incubated the syringe as a 3D cultu

:Immediate reconstruction of orbitomaxillary defects is challenging for head and neck reconstructive surgeons. The primary goals of orbitomaxillary reconstruction are to cover the skin and mucosal defects, fill the defect space, and reconstruct the natural facial contour. This report describes 2 patients who underwent extended orbitomaxillectomy and immediate reconstruction using a combined latiss

BACKGROUND AND AIM:The reduced incidence of donor site morbidity after deep inferior epigastric perforator (DIEP) flap is because the rectus muscle and its fascia are preserved. However, no study has proved that trunk flexion recovers not by the compensatory effect of the contralateral rectus muscle but by reinnervation of the ipsilateral rectus muscle. We hypothesized that if sufficient reinnerva

BACKGROUND:Immediate autologous breast reconstruction after skin-sparing mastectomy is an esthetically superior method, and a free abdominal flap is often used. However, in Asian patients, little redundant abdominal skin and thin subcutaneous tissue are common, necessitating the development of a more suitable flap design and setting. We devised a narrow flap, the sombrero-shaped flap (S-flap), set

:Serious lip injuries can occur during orthognathic surgery. Although an Angle Wider device, which is commonly used during orthognathic surgery, provides some lip protection, it leaves more than half of the lip exposed to surgical instruments. Here, we describe a novel technique to protect the entire upper and lower lips during orthognathic surgery using a minilaparotomy wound edge protector (Lap-

:A deep burn wound is a critical condition that generally necessitates vascularized tissue coverage. We performed the injection of platelet-derived factor concentrates combined with non-cross-linked hyaluronic acid scaffolds for 2 patients with critical burn wounds with bone and tendon exposure and achieved successful healing. Hyaluronic acid was considered to have served as a controlled-release c

BACKGROUND AND AIM:The reduced incidence of donor site morbidity after deep inferior epigastric perforator (DIEP) flap is because the rectus muscle and its fascia are preserved. However, no study has proved that trunk flexion recovers not by the compensatory effect of the contralateral rectus muscle but by reinnervation of the ipsilateral rectus muscle. We hypothesized that if sufficient reinnerva

BACKGROUND:Immediate autologous breast reconstruction after skin-sparing mastectomy is an esthetically superior method, and a free abdominal flap is often used. However, in Asian patients, little redundant abdominal skin and thin subcutaneous tissue are common, necessitating the development of a more suitable flap design and setting. We devised a narrow flap, the sombrero-shaped flap (S-flap), set

Although various injection techniques of hyaluronic acid (HA) filler for facial rejuvenation have been developed, correction of deep wrinkles/grooves, such as the nasolabial fold (NLF), with intradermal or subdermal injections remains difficult. We tested the intradermal HA injection method to place multiple HA struts by (1) inserting a small needle perpendicularly to the wrinkle and (2) injecting HA as intradermal struts with the skin fully stretched by the practitioner's fingers. The results of both NLFs in 10 patients suggest that this technique improves NLFs and maintain the effects more consistently than conventional techniques, although the effects of both methods were almost lost after 6 months. Selective and/or combined application of this technique may enhance the current approach to facial rejuvenation with dermal fillers.