Fat Graft with Allograft Adipose Matrix and Magnesium Hydroxide-Incorporated PLGA Microspheres for Effective Soft Tissue Reconstruction.

BACKGROUND: Autologous fat grafting is one of the most common procedures used in plastic surgery to correct soft tissue deficiency or depression deformity. However, its clinical outcomes are often suboptimal, and lack of metabolic and architectural support at recipient sites affect fat survival leading to complications such as cyst formation, calcification. Extracellular matrix-based scaffolds, such as allograft adipose matrix (AAM) and poly(lactic-co-glycolic) acid (PLGA), have shown exceptional clinical promise as regenerative scaffolds. Magnesium hydroxide (MH), an alkaline ceramic, has attracted attention as a potential additive to improve biocompatibility. We attempted to combine fat graft with regenerative scaffolds and analyzed the changes and viability of injected fat graft in relation to the effects of injectable natural, and synthetic (PLGA/MH microsphere) biomaterials. METHODS: In vitro cell cytotoxicity, angiogenesis of the scaffolds, and wound healing were evaluated using human dermal fibroblast cells. Subcutaneous soft-tissue integration of harvested fat tissue was investigated in vivo in nude mouse with random fat transfer protocol Fat integrity and angiogenesis were identified by qRT-PCR and immunohistochemistry. RESULTS: In vitro cell cytotoxicity was not observed both in AAM and PLGA/MH with human dermal fibroblast. PLGA/MH and AAM showed excellent wound healing effect. In vivo, the AAM and PLGA/MH retained volume compared to that in the only fat group. And the PLGA/MH showed the highest angiogenesis and anti-inflammation. CONCLUSION: In this study, a comparison of the volume retention effect and angiogenic ability between autologous fat grafting, injectable natural, and synthetic biomaterials will provide a reasonable basis for fat grafting.

Prevention of Breast Implant Displacement Using the Acellular Dermal Matrix Garter Belt.

BACKGROUND: Since the issue of breast implant-associated anaplastic large cell lymphoma, smooth breast implants tend to be the more preferred option in implant-based breast reconstructions, compared to its use previously. The most unfavorable aspect of smooth implants is lateral and inferior displacements, which are more common in patients who undergo breast reconstruction compared to augmentation mammoplasty. Hence, we introduce a prevention method for implant displacement using an acellular dermal matrix garter belt. METHODS: This study is a retrospective review of patients who had undergone implant-based breast reconstruction between April 2019 and December 2020. Some patients who have highly possibility of implant displacement, had undergone the application of an ADM garter belt to prevent lateral or superior displacement. Implant displacement was assessed before and at least 6 months postoperatively. RESULTS: A total of 155 IBR cases were recorded. ADM garter belts were applied in 27 patients (17.4%) who had a high tendency of implant displacement for several reasons, which could be classified into two categories: wide breast pocket (56%) and tight inferomedial breast pocket (44%). The intraoperative average distance of lateral slipping on patients' reconstructed breasts from the chest wall midline in supine position was 3.02 ± 0.81 cm and corrected to1.54 ± 0.69 cm at least 6 months postoperative follow-up. CONCLUSIONS: We utilized an ADM strap as an internalized garter belt to minimize implant displacement. This ADM garter belt combined with capsuloplasty might be an effective way to prevent the displacement of smooth implants in the patients with a greater risk of implant displacement. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors   www.springer.com/00266.

New Bone Formation in the Whole Decellularized Cortical Bone Scaffold Using the Model of Revitalizing a Haversian System.

ABSTRACT: Decellularized allogeneic bone chips act as scaffolds for bone tissue regeneration. Owing to their lack of osteogenic potentials compared to autologous bone graft, decellularized bone scaffolds (DBSs) have applied only to small partial bone defects in clinical settings. Furthermore, only decellularized cancellous bone chips have been limitedly used for the purpose of bone regeneration. The cortical bone has less porosity and less osteogenic materials such as bone morphogenetic proteins in comparison with cancellous bone. In this study, we tried to accelerate new bone formation within the decellularized cortical bone scaffold using a vascular pedicle as an in vivo bioreactor.Forty DBSs were divided into 4 groups with different conditionings (DBS+ demineralized bone matrix [DBM], DBS+DBM+me+mesenchymal stem cells, DBS+DBM+vascular pedicle, and DBS+DBM+vascular pedicle+mesenchymal stem cells) and implanted into the back of 5 rabbits. Half of the DBSs were examined at 8 weeks and the other half at 16 weeks to determine vascularization level and osteogenesis within each group. New bone formation and bone-forming cells related to osteogenesis were observed via histological staining. Inclusion of the vascular pedicle resulted in larger areas of bone regeneration. With time, osteon structures became more prominent in groups containing the vascular pedicle.In summary, vascularized DBSs combined with a vascular pedicle have shown promising results for bone regeneration, thereby representing potential therapeutic alternatives for autologous bone grafts or bone tissue free transfer in large or segmental bone defects. In addition, demineralized whole cortical bone matrix along with vascular pedicle and various bone inductive materials, such as DBM and recombinant human bone morphogenetic protein-2, may be an additional new option of an ideal osteoinductive system.

Nipple Reconstruction Using the Semilunar Flap and Omega-shaped Acellular Dermal Matrix Strut.

BACKGROUND: Various operative methods exist for nipple reconstruction. Selection of an appropriate skin flap and core strut material is imperative in achieving a satisfactory outcome in nipple reconstruction. Long-term maintenance of nipple projection requires further investigation by surgeons. We propose a new technique that uses a semilunar flap and omega-shaped acellular dermal matrix (ADM). METHODS: Total 53 nipples were reconstructed by this method. An omega-shaped ADM strut was inserted into the barrel made by a semilunar flap. The footplates of omega-shaped ADM struts were spread out under the subcutaneous tissue of the donor site of the semilunar flap to support the dome of the omega strut. RESULTS: The mean maintenance rate of nipple projection was 95.12 ± 6.30% at 3 weeks, 80.60 ± 8.93% at 3 months, and 71.70 ± 8.67% at 6 months postoperatively when compared to the projection observed in the immediate postoperative period. Thirty-five patients (66.0%) showed a maintenance rate over 70% at 6 months post operation, with most patients (94.3%) demonstrating a maintenance rate greater than 60%. CONCLUSIONS: Our study with the omega-shaped ADM strut showed superior maintenance rates of projection when compared to other studies on that used AlloDerm® as a core strut for nipple reconstruction. Omega-shaped struts, when made with cross-linked thick ADM, supported the skin flap quite well. We propose that our method combining the semilunar flap with an omega-shaped ADM may be a good option for nipple reconstruction. LEVEL OF EVIDENCE IV: "This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors   www.springer.com/00266 ."

The Prevalence and Clinical Characteristics of Hepatitis-delta Infection in Korea / 대한간학회지

BACKGROUND/AIMS: The prevalence of hepatitis delta virus (HDV) infection has been estimated as being approximately 5% among global HBsAg carriers. The anti-delta positive rate in Koreans had been reported as being 0.85% in 1985. While the prevalence of HBV has been decreased from nearly 10% to 5% during the past twenty years, there have been no more studies on the anti-delta prevalence in Koreans. The aim of this study was to estimate the anti-delta prevalence in Koreans and to study the clinical characteristics of anti-delta positive patients in a single center. METHODS: Serum anti-delta was measured in one hundred ninety four HBsAg-positive patients who were admitted to our hospital from February 2003 to August 2003. We checked the genotypes of the HBV in the anti-delta positive patients. The clinical features of the anti-delta positive patients were compared to those clinical features of the anti-delta negative patients from the aspect of age, gender, mode of transmission, the positivity of HBeAg and serum HBV DNA. RESULTS: Serum anti-delta was positive in seven patients among the 194 subjects, giving a 3.6% positive rate. Among these seven patients, six had hepatocellular carcinoma (HCC) and the other one had cholangiocarcinoma. All of the anti-delta positive patients had the C genotype of HBV. The anti-delta positive patients showed significantly suppressed HBV DNA replication compared to the anti-delta negative patients. CONCLUSIONS: In Koreans, anti-delta was positive mainly in HCC patients with an approximate prevalence of 4%, and this rate has not changed much for the past twenty years. HBV DNA replication was suppressed by HDV infection.