One of the major drawbacks associated with autologous fat grafting is unpredictable graft retention. Various efforts to improve the survivability of these cells have been explored, but these methods ...are time‐consuming, complex, and demand significant technical skill. In our study, we examine the use of cryopreserved amniotic membrane as a source of exogenous growth factors to improve adipocyte survivability under normal and hypoxic conditions. Human primary preadipocytes were cultured in a gelatin‐ferulic acid (Gtn‐FA) hydrogel with variable oxygen concentration and treated with amniotic membrane‐derived condition medium (CM) for 7 days. This hydrogel provides a hypoxic environment and also creates a 3D cell culture to better mimic recipient site conditions. The O2 concentration in the hydrogel was measured by electron paramagnetic resonance oxygen imaging (EPROI). The conjugation of FA was confirmed by FTIR and NMR spectroscopy. The cell viability and adipocyte differentiation were analyzed by alamarBlue™ assay, Oil Red O staining, and RT‐qPCR. The expression of genes: Pref‐1, C/EBP β, C/EBP α, PPAR‐ƴ, SLC2A4, and VEGF‐A were quantified. The cell viability results show that the 50% CM showed significantly higher cell pre‐adipocyte cell viability. In addition, compared to normal conditions, hypoxia/CM provided higher PPAR‐ƴ (p < .05), SLC2A4, and VEGF‐A (p < .05) (early and terminal differentiating markers) mRNA expression. This finding demonstrates the efficacy of amniotic CM supplementation as a novel way to promote adipocyte survival and retention via the expression of key gene markers for differentiation and angiogenesis.
BACKGROUND:Studies have cited possible complications and increased fluid accumulation in implant-based breast reconstruction using acellular dermal matrix. The authors propose a novel approach, ...manually meshing acellular dermal matrix using a skin graft mesher before use in expander-based breast reconstruction. The authors investigated postoperative drain time, complication rates, pain, and length of hospital stay in meshed versus unmeshed acellular dermal matrix cohorts.
METHODS:One hundred fourteen patients and 194 reconstructed breasts were included overall. Of these, 99 patients were included in the pain and postoperative length of hospital stay analysis. Independent t test and chi-square analyses were used for bivariate comparisons. Multiple linear regression analyses were used to further delineate impact of meshing acellular dermal matrix on drain time, postoperative parenteral narcotic requirements, and length of stay between the two cohorts.
RESULTS:The meshed acellular dermal matrix cohort had lower overall complication rates compared with the unmeshed cohort. Multiple linear regression analyses showed meshing the acellular dermal matrix alone decreased drain time by 7.3 days, and decreased postoperative parenteral narcotic requirements by 77 percent (20 mg morphine). Furthermore, it was the only significant predictor for a decrease in length of stay.
CONCLUSIONS:Meshing acellular dermal matrix significantly decreased the time needed for postoperative drains. Statistical analysis showed significantly decreased overall and minor complication rates in the meshed cohort. Meshing significantly decreased parenteral narcotic requirements and, importantly, also decreased length of stay. All of these factors have important implications regarding cost and quality of care in expander-based breast reconstruction.
CLINICAL QUESTION/LEVEL OF EVIDENCE:Therapeutic, III.
The cell survival theory and the cell replacement theory contribute to the current thinking regarding free adipose graft persistence after transplantation and influence the principles applied to ...autologous fat transfer procedures. Both theories necessitate the reestablishment of circulation for graft survival. To minimize ischemic death, according to Khouri, fat grafts should be injected with at most 1.6-mm-wide ribbons to optimize the graft-to-recipient interface for oxygen diffusion and neovascularization. The graft is eventually incorporated into the surrounding tissue. We present a curious intraoperative finding, in a 51-year-old woman 2.5 months post-grafting for failed implant reconstruction after radiation. Several large, well-circumscribed, clearly viable adipose tissue nodules, up to 2 cm in diameter, were present inside the capsule. These were so loosely attached to the capsule of the breast pocket that a mere gentle hand sweep and irrigation after opening the cavity caused them to dislodge and float to the surface of the irrigation fluid. This finding begs additional questions about the current understanding of the mechanisms of tissue viability after grafting. It raises the clinical possibility that larger aliquots of transferred fat can be viable than previously perceived.
Technical skills of residents have traditionally been evaluated using subjective In-Training Evaluation Reports (ITERs). We have developed the McGill Inanimate System for Training and Evaluation of ...Laparoscopic Skills (MISTELS), an objective measure of laparoscopic technical ability. The purpose of the study was to assess the concurrent validity of the MISTELS by exploring the relationship between MISTELS score and ITER assessment.
Fifty surgery residents were assessed on the MISTELS system. Concurrent ITER assessments of technical skill were collected, and the proportion of superior ratings for the year was calculated. Statistical comparisons were performed by ANOVA and chi-square analysis. The Pearson correlation coefficient was used to compare the scores in the MISTELS with the ITER ratings.
The 50 residents received 277 ITERs for the year, of which 103 (37%) were “superior,” 170 (61%) “satisfactory,” 4 (1%) “borderline,” and 0 “unsatisfactory.” The MISTELS score correlated moderately well with the proportion of superior ITER scores (r = 0.51, p < 0.01). Residents who passed the MISTELS had a higher proportion of superior ITER assessments than those who failed the MISTELS (p = 0.02), but residents who performed below their expected level on the MISTELS still received mainly satisfactory ITERs (82 ± 18%).
The ITER assessment is poor at identifying residents with below-average technical skills. Residents who perform well in the MISTELS laparoscopic simulator also have better ITER evaluations, providing evidence for the concurrent validity of the MISTELS. Multiple assessment instruments are recommended for assessment of technical competency.
BACKGROUND:Studies have cited possible complications and increased fluid accumulation in implant based breast reconstruction using acellular dermal matrix (ADM). We propose a novel approach, manually ...meshing ADM using a skin graft mesher prior to use in expander based breast reconstruction. We investigated postoperative drain time, complication rates, pain, and length of hospital stay in meshed versus unmeshed ADM cohorts.
METHODS:114 patients and 194 reconstructed breasts were included over all. Of these, 99 patients were included in the pain and post-operative length of hospital stay analysis (LOS). Independent T-test and chi-square analyses were employed for bivariate comparisons. Multiple linear regression analyses were used to further delineate impact of meshing ADM on drain time, post-operative parenteral narcotic requirements and LOS between the two cohorts.
RESULTS:The meshed ADM cohort had lower overall complication rates compared to the unmeshed cohort. Multiple linear regression analyses showed meshing the ADM alone decreased drain time by 7.3 days, and decreased postoperative parenteral narcotic requirements by 77% decrease (20 mg morphine). Furthermore, it was the only significant predictor for a decrease in LOS.
CONCLUSIONS:Meshing ADM significantly decreased the time needed for post-operative drains. Statistical analysis showed significantly decreased overall and minor complication rates in the meshed cohort. Meshing significantly decreased parenteral narcotic requirements, and importantly also decreased the length of stay. All of these factors bear important implications to cost and quality of care in expander based breast reconstruction.
Ketamine (KET), a non-competitive N-methyl-d-aspartate (NMDA) receptor antagonist, has rapid onset of antidepressant effects in Treatment-Resistant Depression patients and repeated infusions are ...required to sustain its antidepressant properties. However, KET is an addictive drug, and so more preclinical and clinical research is needed to assess the safety of recurring treatments in both sexes. Thus, the aim of this study was to investigate the reinforcing properties of various doses of KET (0-, 0.125-, 0.25-, 0.5 mg/kg/infusion) and assess KET’s cue-induced reinstatement and neuronal activation in both sexes of Long Evans rats. Neuronal activation was assessed using the protein expression of the immediate early gene cFos in the nucleus accumbens (Nac), an important brain area implicated in reward, reinforcement and reinstatement to most drug-related cues. Our findings show that KET has reinforcing effects in both male and female rats, albeit exclusively at the highest two doses (0.25 and 0.5 mg/kg/infusion). Furthermore, we noted sex differences, particularly at the highest dose of ketamine, with female rats displaying a higher rate of self-administration. Interestingly, all groups that self-administered KET reinstated to drug-cues. Following drug cue-induced reinstatement test in rats exposed to KET (0.25 mg/kg/infusion) or saline, there was higher cFos protein expression in KET-treated animals compared to saline controls, and higher cFos expression in the core compared to the shell subregions of the Nac. As for reinstatement, there were no notable sex differences reported for cFos expression in the Nac. These findings reveal some sex and dose dependent effects in KET’s reinforcing properties and that KET at all doses induced similar reinstatement in both sexes. This study also demonstrated that cues associated with ketamine induce comparable neuronal activation in the Nac of both male and female rats. This work warrants further research into the potential addictive properties of KET, especially when administered at lower doses which are now being used in the clinic for treating various psychopathologies.
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•Ketamine is reinforcing in both male and female rats.•At the highest dose, ketamine is more reinforcing in female rats.•No sex differences in Ketamine’s cue-induced reinstatement or in cFos activation in nucleus accumbens.•Ketamine cues increase cFos expression in the core subregions of the Nac.
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