Breast Lipofilling Does Not Pose Evidence of Chronic Inflammation in Rats.

BACKGROUND: Laboratory reports on adipose tissue suggest that fat grafting to the breast may pose an oncologic risk. One possible reason for this is the theoretic chronic inflammation due to adipokynes released by grafted white adipose tissue (WAT). OBJECTIVES: The aim of this study was to analyze inflammatory activity in lipofilled breast through the use of proinflammatory markers. METHODS: Fifty-four paired-breasts of female rats were divided into 4 groups: control, sham, and breasts grafted with either autologous subcutaneous (SC) WAT or autologous omentum (OM). The WAT was prepared through centrifugation, and the grafting was performed with the use of 0.9-mm blunt-tip cannula. The rats were killed 8 weeks postoperatively, and their breasts were harvested for immunohistochemical staining for CD68-expressing macrophages, gene expression (real-time PCR) for monocyte chemoattractant protein 1 (MCP-1), F4/80, Cox-2, and IL-6. RESULTS: The weights of the rats that underwent a procedure differed from those of the unmanipulated control group (P < 0.01). The macrophage counts of CD68 differed only between breasts lipofilled with OM and control (P < 0.01). MCP-1, F4/80, and Cox-2 were similarly expressed among the groups (P = 0.422, P = 0.143, and P = 0.209, respectively). The expression of IL-6 differed between breast samples grafted with SC and OM WAT (P = 0.015), but not between samples of control and OM (P = 0.752), and control and SC (P = 0.056). CONCLUSIONS: No inflammation activity was identified in the microenvironment of lipofilled breasts, indicating that chronic inflammation does not seem to be triggered by the breast lipofilling procedure.

Assessment of the Cancer Risk of the Fat-Grafted Breast in a Murine Model.

Background: The results of experimental studies indicate that grafting of autologous adipose tissue may induce tumorigenesis at the recipient site, but clinical results do not support a carcinogenic effect of fat grafting to the breast. Objectives: The authors assessed cancer risk following transplantation of autologous fat into murine mammary tissue. Methods: In this animal study, mammary tissues from 54 breasts of 9 female rats were either grafted with autologous subcutaneous fat, grafted with autologous omental fat, or unmanipulated. Tissues were harvested and processed for histologic and immunohistochemical analyses, and the mRNA expression levels of specific genes were determined. Results: No atypia or changes in lobular structures were observed in lipofilled breasts compared with controls. The numbers of ductal cell layers and terminal ductal units were similar for lipofilled and control breasts. Macrophage concentrations also were similar for the 3 groups. The localization and magnitude of plasminogen activator inhibitor 1 were similar for lipofilled and unmanipulated breast tissue. The percentages of cells expressing Ki67 or estrogen receptor (ER) and the ER/Ki67 balance were similar for the 3 groups. Gene expression was not altered in lipofilled breasts, compared with controls. Conclusions: No theoretical risk of cancer was detected in the microenvironment of the lipofilled rat breast.

Fat Grafting to the Breast, a Simple Procedure for a Very Complex Reconstruction.

Usually, complicated reconstructions demand complex procedures. However, we report an unpublished situation where lipofilling was the only effective procedure for breast reconstruction, once 4 previous procedures, including 2 microvascular free flaps, had failed. The reported case describes a woman without subcutaneous tissue in the left breast topography, with radiation sequelae resulting in a fibrotic, hyperchromic, unexpandable skin that was tethered to her costal bone and pleura. The 4 previous attempts of breast reconstruction resulted in unavailable nearby recipient vessels, and this situation appointed breast lipofilling as the most feasible procedure. This report shows the power of breast lipofilling, a simple procedure that can be used even for the more complex reconstructions.

The Underlying Social Dynamics of Paradigm Shifts.

We develop here a multi-agent model of the creation of knowledge (scientific progress or technological evolution) within a community of researchers devoted to such endeavors. In the proposed model, agents learn in a physical-technological landscape, and weight is attached to both individual search and social influence. We find that the combination of these two forces together with random experimentation can account for both i) marginal change, that is, periods of normal science or refinements on the performance of a given technology (and in which the community stays in the neighborhood of the current paradigm); and ii) radical change, which takes the form of scientific paradigm shifts (or discontinuities in the structure of performance of a technology) that is observed as a swift migration of the knowledge community towards the new and superior paradigm. The efficiency of the search process is heavily dependent on the weight that agents posit on social influence. The occurrence of a paradigm shift becomes more likely when each member of the community attaches a small but positive weight to the experience of his/her peers. For this parameter region, nevertheless, a conservative force is exerted by the representatives of the current paradigm. However, social influence is not strong enough to seriously hamper individual discovery, and can act so as to empower successful individual pioneers who have conquered the new and superior paradigm.

Unmanipulated native fat exposed to high-energy diet, but not autologous grafted fat by itself, may lead to overexpression of Ki67 and PAI-1.

BACKGROUND: Although its unclear oncological risk, which led to more than 20 years of prohibition of its use, fat grafting to the breast is widely used nowadays even for aesthetic purposes. Thus, we proposed an experimental model in rats to analyze the inflammatory activity, cellular proliferation and levels of Plasminogen Activator Inhibitor (PAI-1) in grafted fat, and in native fat exposed to high-energy diet in order to study the oncological potential of fat tissue. METHODS: Samples of grafted fat of rats on regular-energy diet were compared with paired samples of native fat from the same rat on regular-energy diet and on high-energy diet in a different time. Analysis involved microscopic comparisons using hematoxylin-eosin staining, immunohistochemistry with anti-CD68-labelled macrophages, and gene expression of Ki-67 and PAI-1. RESULTS: Hematoxylin-eosin staining analyses did not find any atypical cellular infiltration or unusual tissue types in the samples of grafted fat. The inflammatory status, assessed through immunohistochemical identification of CD68-labelled macrophages, was similar among samples of native fat and grafted fat of rat on regular-energy diet and of native fat of rats on high-energy diet. Real-time PCR revealed that high-energy diet, but not fat grafting, leads to proliferative status on adipose tissue (overexpression of ki-67, p = 0.046) and raised its PAI-1 levels, p < 0.001. CONCLUSION: While the native adipose tissue overexpressed PAI-1 and KI67 when exposed to high-energy diet, the grafted fat by itself was unable to induce cellular proliferation, chronic inflammatory activity and/or elevation of PAI-1 levels.

Omentum for Mammary Disorders: A 30-Year Systematic Review.

PURPOSE: Although the safety of applying omentum to the female breast for total breast reconstruction is controversial, it has recently been used to treat certain mammary disorders as well. A systematic review was therefore conducted to analyze and establish the suitability and safety of applying omentum to the breast. METHODS: Covereing the interval from January 1984 to December 2013, we performed searches in MEDLINE, Embase, SciELO, and Google-Scholar for original articles describing the applicability of greater omentum to the breast and its clinical complications. RESULTS: Sixty observational articles with 985 women were chosen. The main clinical indications were total breast reconstruction after mastectomy due to breast cancer (45 studies), radiation damage (23 studies), and congenital Poland syndrome (4 studies). Altogether, 273 complications were identified among the 985 women treated. The most frequent was flap necrosis (26.74 %). The most serious was injury to the digestive system (1.10 %). There was a 35.48 % incidence of local breast cancer recurrence in eight observational studies on oncological risk. Seven of the eight included only women with advanced cancer. One of these studies reported the incidence and relapse time predominantly according to the primary tumor size. CONCLUSIONS: Although the oncological risk remains unclear, there was a high volume of complications that affected the digestive system. These findings suggest that omentum has well established applicability, but only for total breast reconstruction of huge defects, where muscular/myocutaneous or perforator flaps may be unsuitable.

Individual differences in schedule-induced polydipsia: neuroanatomical dopamine divergences.

Autoradiography analysis of D1 and D2 dopamine receptors and c-Fos activity were performed in brain of rats classified as low drinkers (LD) and high drinkers (HD) according to schedule-induced polydipsia (SIP) performance. Previous studies have shown that groups selected according to their rate of drinking in SIP differ in behavioral response to dopaminergic drugs. This study reports differences between LD and HD rats in dopamine D1 and D2 receptor binding through different mesocorticolimbic brain areas. LD and HD rats showed opposite patterns of binding in dopamine D1 and D2 receptors in the nucleus accumbens, medial prefrontal cortex, amygdala, ventral tegmental area and substantia nigra. Whereas LD rats showed higher binding than HD rats for D1 receptors, HD rats showed higher binding than LD rats for D2 receptors (except in substantia nigra that were roughly similar). These neuroanatomical differences in dopamine receptor binding were also associated with an elevated c-Fos count in the medial prefrontal cortex of HD rats. In tandem with previous evidence, our results suggest a different dopaminergic function between LD and HD, and points to SIP as a behavioral model for distinguishing populations possibly vulnerable to dopaminergic function disorders.

The effects of partial and complete masculinization on the sexual differentiation of nuclei that control lordotic behavior in the male rat.

Male rats, under certain experimental conditions, may show lordosis, the typical expression of female sexual receptivity. This work studies the sexual morphological pattern of facilitatory and inhibitory structures that control lordosis. Three groups of males were neonatally subjected to a gradient of androgen exposure (castrated plus injected oil (GxM+oil); castrated plus androstenedione treated (GxM+AND); and sham operated [CM]); a group of control females (CF) was also added. Lordotic response after these different hormonal and neonatal surgical treatments, as well as the volume or number of neurons in facilitatory (ventromedial nucleus of the hypothalamus [VMN]) and inhibitory (the intermediate region of the lateral septum [LSi] and accessory olfactory bulb [AOB]) nuclei involved in lordosis was studied in adults. The inhibition of lordosis in the males seems to be associated to the neonatal presence of testosterone and the consequent masculinization of the VMN, VMNvl, LSi and AOB. It is suggested that one of the functions of the sex differences consistently seen in these structures might be to inhibit the lordosis response in the male.