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Medical devices made from poly(dimethylsiloxane) (PDMS)‐based silicone implants have been broadly used owing to their inert properties, biocompatibility, and low toxicity. However, long‐term implantation is usually associated with complications, such as capsular contracture due to excessive local inflammatory response, subsequently requiring implant removal. Therefore, modification of the silicone surface to reduce a risk of capsular contracture has attracted increasing attention. Human adipose‐derived stem cells (hASCs) are known to provide potentially therapeutic applications for tissue engineering, regenerative medicine, and reconstructive surgery. Herein, hASCs coating on a PDMS (hASC‐PDMS) or itaconic acid (IA)‐conjugated PDMS (hASC‐IA‐PDMS) surface is examined to determine its biocompatibility for reducing capsular contracture on the PDMS surface. In vitro cell cytotoxicity evaluation showed that hASCs on IA‐PDMS exhibit higher cell viability than hASCs on PDMS. A lower release of proinflammatory cytokines is observed in hASC‐PDMS and hASC‐IA‐PDMS compared to the cells on plate. Multiple factors, including in vivo mRNA expression levels of cytokines related to fibrosis; number of inflammatory cells; number of macrophages and myofibroblasts; capsule thickness; and collagen density following implantation in rats for 60 days, indicate that incorporated coating hASCs on PDMSs most effectively reduces capsular contracture. This study demonstrates the potential of hASCs coating for the modification of PDMS surfaces in enhancing surface biocompatibility for reducing capsular contracture of PDMS‐based medical devices. [ABSTRACT FROM AUTHOR]

Byline: Stamatis. Sapountzis, Hyoung. Park, Ji. Kim, Achilleas. Chantes, Rong. Beak, Chan. Heo Background: The treatment of pressure sores represents a significant challenge to health care professionals. Although, pressure wound [...]

Pulmonary artery hypertension (PAH) is a progressive chronic disease with a high mortality rate. Increased pulmonary vascular resistance and over-proliferation of pulmonary artery endothelial cells lead to remodeling of pulmonary vasculature. Several anti-PAH therapies targeting various pathways involved in PAH progression have been approved by the FDA. However, many of the currently available anti-PAH drugs suffer from a number of limitations, including short biological half-life, and poor pulmonary selectivity. Prostaglandin E1 (PGE1) is a compound with vasodilatory, anti-inflammatory, anti-aggregatory, and anti-proliferative properties. Recently, PGE1 is known to accumulate in sites of inflammation or vascular lesions and thus enhance the effects of the drugs and alleviate the side effects. Therefore, we hypothesized that long-term effect of PGE1 could reduce ma adaptive structural remodeling of the lung and heart and prevent ventricular arrhythmias in monocrotaline (MCT)-induced rat model of PAH. Our results revealed that PGE1 reduced ventricular hypertrophy, protein expressions of endothelin-1 (ET-1) and endothelin receptor A (ERA), and the expression of fibrosis. These results support the notion that PGE1 can improve the functional properties of RV, highlighting its potential benefits for heart and lung impairment. [ABSTRACT FROM AUTHOR]

Summary Background This study aims to determine whether a bar-like implant made of poly lactic- co -glycolic acid (PLGA) could be used for cartilage suspension and whether the implant would be suitable for rhinoplasty. Methods Three types of in vivo animal experiments were performed. First, the ear cartilage was incised in a full-thickness pattern, and the PLGA system was placed between the upper and lower cartilage to offer support to the tissue. Second, after the ear cartilage was forcibly bent, an implant was placed in the cartilage. For these rabbits, the outer aspect of the ear cartilage was assessed at 2, 4, 8, 10, and 12 weeks postoperatively. In addition, tissue samples were collected for histological evaluation 12 weeks after surgery. Third, the bar-like nasal implant was used for nasal septal suspension. We obtained micro-computed tomography (CT) images and evaluated the inflammatory reaction at 12 weeks postoperatively. Results The results of both the ear suspension and bending retention tests revealed that the characteristic shapes of the cartilage were well preserved at 12 weeks postoperatively. Moreover, no abnormal inflammatory reaction was present in any site in the experimental group. We successfully implanted the bar-like nasal implant in the rabbit's septum, and no complications occurred. Furthermore, the physical examination and the micro-CT images did not reveal any nasal obstruction or inflammation. Conclusions We confirmed that an implant made of PLGA can be maintained in the cartilage tissue and believe that this can be applied in rhinoplasty as an alternative to autologous cartilage. [ABSTRACT FROM AUTHOR]

Background:Ischaemia-reperfusion injury (IRI) results in oxidative damage and a profound inflammatory reaction, leading to cell death. GV 1001 is a telomerase-based 16-mer peptide vaccine developed against cancer. However, it has also been reported to possess antioxidant and anti-inflammatory properties. The aim of this study was to determine if GV 1001 can reduce the negative effects caused by IRI in a rat skin flap model owing to its anti-oxidant and anti-inflammatory properties. Materials and methods:In order to evaluate the effect of GV 1001, 5 × 5 cm2inferior epigastric artery based island skin flaps were dissected in 39 8-week-old Sprague-Dawley rats weighing 220–270 g. The rats were divided into three groups: (I) non-ischaemic group; (II) IRI with saline; and (III) IRI with 10 mg GV 1001 treatment. Drugs were administered intra-muscularly directly before and after ischaemia. Flap survival area, neutrophil infiltration, cytokine levels (interleukin [IL]-1, IL-6, and tumour necrosis factor-α), malondialdehyde (MDA) level, and superoxide dismutase (SOD) activity were measured. Flap survivability was analysed at 7 days after surgery. Results:Flap survival area was significantly larger in group III than in group II. Cytokine release level was also significantly lower in group III. Neutrophil infiltration grade, MDA level, and SOD activity slightly decreased in Group III; however, the changes were not statistically significant. Conclusion:These results imply that GV 1001 exerts a protective effect against IRI through antioxidant effects, reducing reactive oxygen species, and suppressing the inflammatory cascade. [ABSTRACT FROM AUTHOR]

We hypothesize that periodically early, local suppression of cysteinyl leukotrienes (CysLTs), which are potent inflammatory mediators, can reduce the fibrotic capsular contracture around silicone implants. We tested this hypothesis with the silicone implants enabled with the sustained release of montelukast, a CysLT receptor antagonist, for 3 and 15 days. In this work, we inserted each of the distinct implants into the pocket of the subpanniculus carnosus plane of living rats and performed histological and immunofluorescent (IF) analyses of the tissues biopsied at predetermined periods for 12 weeks after implant insertion. The implants with montelukast exhibited significantly reduced polymorphonuclear leukocytes (i.e., PMNs), implying a concurrent reduction of CysLT. This effect was more prominent after long-term local montelukast exposure. Thus, fewer fibroblasts were recruited, thereby reducing transforming growth factor (TGF)-β and myofibroblasts in the tissue around the implant. Therefore, the fibrotic capsule formation, which was assessed using the capsule thickness and collagen density, decreased along with the myofibroblasts. Additionally, the tissue biopsied at the experimental end point exhibited significantly decreased mechanical stiffness. Statement of Significance Capsular contracture is troublesome, making the tissues hardened around the silicone implant. This causes serious pain and discomfort to the patients, often leading to secondary surgery for implant replacement. To resolve this, we suggest a strategy of long-term, local suppression of cysteinyl leukotriene, an important mediator present during inflammation. For this, we propose a silicone implant abled to release a drug, montelukast, in a sustained manner. We tested our drug-release implant in living animals, which exhibited a significant decrease in capsule formation compared with the intact silicone implant. Therefore, we conclude that the sustained release of montelukast at the local insertion site represents a promising way to reduce capsular contracture around silicone implants. [ABSTRACT FROM AUTHOR]

Background: Although many patients who undergo reduction mammaplasty are obese, reports on whether obesity is a risk factor for postoperative complications have been conflicting. Objectives: This systematic literature review and meta-analysis aimed to evaluate the relationship between obesity and surgical complications after reduction mammaplasty. Methods: The PubMed, Medline, and Embase databases were searched between 1998 and 2016 using the MeSH terms and keywords "reduction mammoplasty (mammaplasty)," "breast reduction," "obesity," "body weight," "body mass index," and "risk factor". Results: Among 26 studies that reported surgical complication risk and patient body weight, 11 concluded that obesity is not a risk factor and 15 reported that high body mass index increases surgical risk. On comparing obese and non-obese patients, we found that obese patients had a higher relative risk of surgical complications (1.38, 95% confidence interval 1.13-1.69), particularly skin and fat necrosis (2.01, 95% confidence interval 1.54-2.63). The pooled risk further increased with an increase in body mass index, and it was 1.71 for body mass index >35 kg/m2 and 2.05 for body mass index >40 kg/m2. Conclusions: Our meta-analysis indicated that the risk of surgical complications and tissue necrosis after reduction mammaplasty is higher in obese patients than in non-obese patients and that the risk gradually increases with an increase in the severity of obesity. The findings of this study could form a basis for preoperative patient education, surgical method selection, and determination of the extent of postoperative care. [ABSTRACT FROM AUTHOR]

Summary Background Breast augmentation with fat transfer does not bear the risks associated with silicone implantation. The method can potentially be especially useful in Asian women, who often reject augmentation mammoplasty with implants. This prospective clinical trial evaluated the effects of external breast expansion on breast density and vessel count using magnetic resonance imaging. Methods Thirty-four enrolled patients were instructed to apply one of two devices, the conventional BRAVA device (used in the AESTES trial) or a novel external expansion device (EVERA) designed for Asian women, continuously for 8 h per day for 12 weeks. For external expansion, the pressure was set to 25 mmHg. Follow-up examinations were performed for 4 weeks after completion of the expansion. The ratio between the fibroglandular and adipose tissues of the breast was measured using T1-weighted MRI, and the number of vessels in the breast tissue was determined before and after the treatment by contrast MRI. Additionally, the volume of the breast was measured by laser scanning before, during, and after the device application. The obtained measurements were compared within and between the groups at different time points. Results Six patients dropped out, while 28 completed the trial without major side effects or adverse events. External expansion significantly increased breast vessel count in both the EVERA and AESTES groups (p = 0.019, p = 0.022). However, it did not significantly change breast density in either group (p = 0.186, p = 0.638). No significant intergroup differences were noted in vessel count (p = 0.874) or density (p = 0.482). Breast volume increases after 12 weeks of application were statistically significant in both groups, with mean changes of 81 ± 22 cc (AESTES) and 98 ± 30 cc (EVERA) (p < 0.001 in both cases). Conclusions External expansion resulted in a marked increase in breast vessel count but did not affect breast density. The observed increase in breast volume can be considered substantial for Asian women. Level of evidence Level II, therapeutic study. [ABSTRACT FROM AUTHOR]