Pressurized intra-peritoneal aerosol chemotherapy (PIPAC): increased intraperitoneal pressure does not affect distribution patterns but leads to deeper penetration depth of doxorubicin in a sheep model.

BACKGROUND: Pressurized Intra-Peritoneal Aerosol Chemotherapy (PIPAC) is an innovative treatment against peritoneal carcinomatosis. Doxorubicin is a common intra-venous chemotherapy used for peritoneal carcinomatosis and for PIPAC. This study evaluated the impact of increased PIPAC intraperitoneal pressure on the distribution and cell penetration of doxorubicin in a sheep model. METHODS: Doxorubicin was aerosolized using PIPAC into the peritoneal cavity of 6 ewes (pre-alpes breed): N = 3 with 12 mmHg intraperitoneal pressure ("group 12") and N = 3 with 20 mmHg ("group 20"). Samples from peritoneum (N = 6), ovarian (N = 1), omentum (N = 1) and caecum (N = 1) were collected for each ewe. The number of doxorubicin positive cells was determined using the ratio between doxorubicine fluorescence-positive cell nuclei (DOXO+) over total number of DAPI positive cell nuclei (DAPI+). Penetration depth (µm) was defined as the distance between the luminal surface and the location of the deepest DOXO+ nuclei over the total number of cell nuclei that were stained with DAPI. Penetration depth (µm) was defined as the distance between the luminal surface and the location of the deepest DOXO+ nuclei. RESULTS: DOXO+ nuclei were identified in 87% of samples. All omental samples, directly localized in front of the nebulizer head, had 100% DOXO+ nuclei whereas very few nuclei were DOXO+ for caecum. Distribution patterns were not different between the two groups but penetration depth in ovary and caecum samples was significantly deeper in group 20. CONCLUSIONS: This study showed that applying a higher intra-peritoneal pressure during PIPAC treatment leads to a deeper penetration of doxorubicin in ovarian and caecum but does not affect distribution patterns.

Analytic comparison of talc in commercially available baby powder and in pelvic tissues resected from ovarian carcinoma patients.

OBJECTIVE: Measure the size and shape of talc particles in talcum powder and compare this data to the size and shape of talc particles found in surgically resected tissues from patients with ovarian carcinoma. METHODS: Using polarized light microscopy (PLM) and scanning electron microscopy (SEM), we measured the size and shape of talc particles in samples of talc-containing baby powder (TCBP) and surgically resected pelvic tissues (hysterectomies) from talc-exposed patients with ovarian carcinoma. RESULTS: The most frequent class of particles in TCBP can be unequivocally identified as talc, using both polarized light microscopy and scanning electron microscopy with energy dispersive X-ray analysis (SEM/EDX). The talc particles found in resected tissues from ovarian carcinoma patients are similar in size and shape to the most abundant morphological class of particles in TCBP. CONCLUSIONS: This finding, combined with previous epidemiological literature and tissue-based analytical studies, provides further evidence that the small, isodiametric particles that dominate TCBP can migrate from the perineum and become lodged in distal structures in the female reproductive tract, where they may lead to an increased risk of developing ovarian carcinoma.

Morphological hallmarks facilitating distinction of omental milky spots and lymph nodes: an exploratory study on their discriminative capacity.

BACKGROUND: Omental milky spots (OMSs) are the primary lymphoid structures of the greater omentum. However, the presence of lymph nodes (LNs) has occasionally been mentioned as well. Understanding which lymphoid structures are present is of significance, especially in gastric tumor metastasis; tumor deposits in omental LNs suggest local lymphatic spread, whereas tumor deposits in OMSs suggest peritoneal spread and hence extensive disease. Since LNs and OMSs share morphological characteristics and OMSs might be wrongly identified as LNs, reliable hallmarks facilitating easy discrimination are needed. MATERIALS AND METHOD: A series of microscopic morphological hallmarks unique to LNs were selected as potential candidates and were assessed for their discriminative capacity: 1) capsule, 2) trabeculae, 3) subcapsular sinus, 4) afferent lymphatic vessels, 5) distinct B- and T cell regions, and 6) a layered organization with, from the outside in a capsule, cortex, paracortex, and medulla. These hallmarks were visualized by multiple staining techniques. RESULTS: Hallmarks 1, 2 5 and 6 were shown to be the most efficient as these were consistent and discriminative. They were best visualized by Picrosirius red, smooth muscle actin and a B-cell / T-cell double staining. CONCLUSION: The presence of a capsule, trabeculae, distinct B- and T-cell regions and a layered organization represent consistent and reliable morphological features which allow to easily distinguish LNs from OMSs, especially when applied in combination.

Identification of biomarkers, pathways and potential therapeutic agents for white adipocyte insulin resistance using bioinformatics analysis.

For the better understanding of insulin resistance (IR), the molecular biomarkers in IR white adipocytes and its potential mechanism, we downloaded two mRNA expression profiles from Gene Expression Omnibus (GEO). The white adipocyte samples in two databases were collected from the human omental adipose tissue of IR obese (IRO) subjects and insulin-sensitive obese (ISO) subjects, respectively. We identified 86 differentially expressed genes (DEGs) between the IRO and ISO subjects using limma package in R software. Gene Set Enrichment Analysis (GSEA) provided evidence that the most gene sets enriched in kidney mesenchyme development in the ISO subjects, as compared with the IRO subjects. The Gene Ontology (GO) analysis indicated that the most significantly enriched in cellular response to interferon-gamma. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that the DEGs were most significantly enriched in cytokine-cytokine receptor interaction. Protein-Protein Interaction (PPI) network was performed with the STRING, and the top 10 hub genes were identified with the Cytohubba. CMap analysis found several small molecular compounds to reverse the altered DEGs, including dropropizine, aceclofenac, melatonin, and so on. Our outputs could empower the novel potential targets to treat omental white adipocyte insulin resistance, diabetes, and diabetes-related diseases.

Topical purified omental lipid formulations in the prevention of skin ulcers: a narrative review.

The omentum is a large peritoneal fold. Its main function is to protect abdominal organs, exerting a defensive action against infective agents. The tissue promotes repair after several types of injury. An extensive vascularisation is the key characteristic of this tissue and the omentum has the highest level of production and content of vascular endothelial growth factor (VEGF). A component of omentum is the lipid compound, which carries out important activities for the organism. Omentum is rich in neutral glycerides, phospholipids, glycolipids and gangliosides. Dermatological products containing purified omental lipids are commercially available and topical omental extracts have been useful in the softening, moisturising and smoothing of skin. Animal-derived omental lipids could be use in topical products with different textures (creams, fluids, emulsions and cleansers) and at different concentrations (10-25%) for the treatment of fragile skin or skin conditions causing risk of ulcer formation. This review summarises the pharmacological rationale of purified omental lipids in topical formulations for use in fragile skin conditions, the clinical efficacy data available in the scientific literature and the potential future perspectives. Efficacy of topical purified omental lipids have been demonstrated in numerous clinical controlled trials involving a total of 320 subjects. These studies demonstrated that this product helps prevent the formation of pressure ulcers (PU) in hospitalised high-risk subjects, improves wound healing process, normalises skin hydration in diabetic subjects with moderate-severe skin xerosis and improve the clinical evolution of diabetic foot. Therefore, purified omental lipid could be an effective tool for the management of fragile skin and the skin at high risk of PU formation.

Clinical value of bioelectrical properties of cancerous tissue in advanced epithelial ovarian cancer patients.

Currently, there are no valid pre-operatively established biomarkers or algorithms that can accurately predict surgical and clinical outcome for patients with advanced epithelial ovarian cancer (EOC). In this study, we suggest that profiling of tumour parameters such as bioelectrical-potential and metabolites, detectable by electronic sensors, could facilitate the future development of devices to better monitor disease and predict surgical and treatment outcomes. Biopotential was recorded, using a potentiometric measurement system, in ex vivo paired non-cancerous and cancerous omental tissues from advanced stage EOC (n = 36), and lysates collected for metabolite measurement by microdialysis. Consistently different biopotential values were detected in cancerous tissue versus non-cancerous tissue across all cases (p < 0.001). High tumour biopotential levels correlated with advanced tumour stage (p = 0.048) and tumour load, and negatively correlated with stroma. Within our EOC cohort and specifically the high-grade serous subtype, low biopotential levels associated with poorer progression-free survival (p = 0.0179, p = 0.0143 respectively). Changes in biopotential levels significantly correlated with common apoptosis related pathways. Lactate and glucose levels measured in paired tissues showed significantly higher lactate/glucose ratio in tissues with low biopotential (p < 0.01, n = 12). Our study proposes the feasibility of biopotential and metabolite monitoring as a biomarker modality profiling EOC to predict surgical and clinical outcomes.

Selected Case From the Arkadi M. Rywlin International Pathology Slide Club: Peritoneal Lipofuscinosis and Deciduosis in Pregnancy.

Peritoneal lipofuscinosis is a very rarely recognized condition occurring during pregnancy characterized by brown pigmentation of the omentum and peritoneum, a decidual reaction and benign mesothelial cells. The iron negative pigment, which is likely to be confused with hemosiderin in the hematoxylin and eosin stain, is lipofuscin. The seminar case, apparently the third published, arose in a 37-year-old woman who presented in October 2015 at 24 weeks pregnancy with abdominal pain. Investigations revealed a ruptured left ovarian cyst and rising serum carcinoembryonic antige levels. At laparotomy, there was no free intraperitoneal blood but the omentum and uterine serosa were black. Histology showed lipofuscinosis and a decidual reaction. The patient delivered a normal baby in February 2016 and was clinically well after delivery. A left ovarian endometriotic cyst was removed in February 2017. The patient made a good recovery with no clinically apparent symptoms from the liposuscinosis. We postulate that the endometriotic cyst had ruptured and released blood into the peritoneal cavity in 2015. The iron from the red cells breakdown was then rapidly resorbed because of the pregnancy requirements for iron, leaving lipofuscin in peritoneal macrophages.

Biodistribution and Clearance of Stable Superparamagnetic Maghemite Iron Oxide Nanoparticles in Mice Following Intraperitoneal Administration.

Nanomedicine is an emerging field with great potential in disease theranostics. We generated sterically stabilized superparamagnetic iron oxide nanoparticles (s-SPIONs) with average core diameters of 10 and 25 nm and determined the in vivo biodistribution and clearance profiles. Healthy nude mice underwent an intraperitoneal injection of these s-SPIONs at a dose of 90 mg Fe/kg body weight. Tissue iron biodistribution was monitored by atomic absorption spectroscopy and Prussian blue staining. Histopathological examination was performed to assess tissue toxicity. The 10 nm s-SPIONs resulted in higher tissue-iron levels, whereas the 25 nm s-SPIONs peaked earlier and cleared faster. Increased iron levels were detected in all organs and body fluids tested except for the brain, with notable increases in the liver, spleen, and the omentum. The tissue-iron returned to control or near control levels within 7 days post-injection, except in the omentum, which had the largest and most variable accumulation of s-SPIONs. No obvious tissue changes were noted although an influx of macrophages was observed in several tissues suggesting their involvement in s-SPION sequestration and clearance. These results demonstrate that the s-SPIONs do not degrade or aggregate in vivo and intraperitoneal administration is well tolerated, with a broad and transient biodistribution. In an ovarian tumor model, s-SPIONs were shown to accumulate in the tumors, highlighting their potential use as a chemotherapy delivery agent.

ECM-based macroporous sponges release essential factors to support the growth of hematopoietic cells.

The success of hematopoietic stem cells (HSCs) transplantation is limited due to the low number of HSCs received from donors. In vivo, HSCs reside within a specialized niche inside the 3D porous spongy bone. The natural environment in the niche is composed of structural proteins, glycosaminoglycans (GAGs) and soluble factors that control cells fate. However, the designed scaffolds for in vitro culture do not fairly recapitulate this microenvironment and cannot efficiently control HSCs fate. Here we report on the development of new omental ECM-based 3D macroporous sponges for hematopoietic cell culture. The scaffolds' structure, porosity and stability were characterized and optimized. Analysis of the biochemical content revealed that they were composed of collagens and GAGs, including sulfated GAGs. This morphology and composition enabled growth factors interaction with the sulfated GAGs, as indicated by the high loading capacity and release profile of three different hematopoietic niche factors. Finally, the ability of the ECM-based scaffolds to efficiently support the growth of hematopoietic cells by releasing stem cell factor (SCF) was demonstrated.

Distribution of persistent organic pollutants in serum, omental, and parietal adipose tissue of French women with deep infiltrating endometriosis and circulating versus stored ratio as new marker of exposure.

Several studies have assessed the potential role of environmental chemicals in the onset, growth, and/or physiopathology of endometriosis. However, their contour in terms of considered exposure markers remains limited. The present study aimed to characterize the internal exposure levels of 78 persistent organic pollutants (POPs, including dioxins, polychlorobiphenyls, brominated flame retardants and organochlorine pesticides) in a set of 113 adult French women (45 controls, 68 cases), and to characterize the distribution of these POPs within three biological compartments (omental adipose tissue, parietal adipose tissue, and serum). For all targeted substances, the correlation between the concentrations measured in omental versus parietal adipose tissue was found strongly significant (p<0.0001). An equivalence of the measures performed in parietal and omental adipose tissue was moreover observed with median levels of 6.4 vs. 7.4pg/gl.w. for WHO-TEQ2005 PCDD/F, 4.5 vs. 4.7pg/gl.w. for WHO-TEQ2005 dl-PCB, 137.1 vs. 147.9ng/gl.w. for sum of 6 ndl-PCB, and 2.1 vs. 2.0ng/gl.w. for sum of 7 i-PBDE, respectively. The same observation was made for individual targeted OCs compounds. Significant correlations were also observed between these concentrations determined in adipose tissue and those measured in serum for dioxins (WHO-TEQ2005 PCDD/F=6.1pg/gl.w), PCBs (WHO-TEQ2005 dl-PCB=3.6pg/gl.w., sum of 6 ndl-PCB=81.1ng/gl.w.), and brominated flame-retardants (sum of 7 i-PBDE=0.9ng/gl.w.). The circulating versus stored ratio of some exposure markers (Sum PCDDs, 1,2,3,6,7,8-HxCDF, slightly versus highly chlorinated PCBs ratio, PBDE 99 and PBB 153) was found statistically different for control and case individuals. These extended exposure data from deep infiltrating endometriosis patients are the first ones available for France and give a new insight about the equilibrium of chemicals between storage and circulating compartments that should be further considered as new marker of exposure in the context of exposure-health relationship studies.

Chemerin activation in human obesity.

OBJECTIVE: Chemerin is an inflammatory adipokine, whose activity is regulated by successive proteolytic cleavages at its C-terminus. It is secreted as an inactive precursor (chem163S); cleavage at Lys158 converts it to chem158K with modest activity. Chem157S is the most potent form and chem155A is inactive. The aim of this study was to determine if chemerin was activated in samples from patients with obesity. METHODS: Using specific ELISAs for different chemerin forms and a pan-chemerin ELISA, chemerin forms in human obesity were characterized. RESULTS: Plasma chemerin from patients with obesity (BMI 44.3 ± 1.3 kg/m(2) , n = 29) was significantly higher than in lean controls (BMI 20.9 ± 0.7 kg/m(2) , n = 10) (160 ± 11 vs. 76.2 ± 5.5 ng/mL, respectively, P < 0.0001). This increase in chemerin was due to increased previously unattributed chemerin, with further C-terminal truncation demonstrated by mass spectrometry, accounting for ∼35% of total plasma chemerin. Chemerin forms in adipose tissue showed a different profile, with minimal chem163S and significant levels of chem157S. Chem155A was present in omental but not in subcutaneous adipose tissue. Unattributed chemerin forms were undetectable in adipose tissue. CONCLUSIONS: Chemerin is activated in adipose tissue of subjects with obesity, and further C-terminal processing occurs during the disposition of chemerin from adipose tissue, resulting in substantial levels of novel degraded forms in plasma that correlate with obesity.

Hepatic epithelioid hemangioendothelioma metastasized to the peritoneum, omentum and mesentery: a case report.

Epithelioid hemangioendothelioma (EHAE) is a malignant vascular tumor derived from endothelial cell often misdiagnosed as Hepatic carcinoma on the basis of radiological features. Till now etiology of this rare curiosity is unknown but it is related with use of oral contraceptives pills (OCP), liver trauma, exposure to vinyl chloride and hepatitis. We herein report on a case which failed to be diagnosed by cytopathology, computed tomography (CT) and magnetic resonance imaging (MRI). Patient was a 46 yr old man presented with abdominal distension for a month. Initial liver function test (LFT) was increased whereas renal function test (RFT) and alpha-fetoprotein (AFP) were normal. His abdominal ultrasound revealed multiple hypoechoic nodules and multiple liver calcifications. Subsequently laparoscopic omental biopsy and Ultrasound guided liver biopsy was done showing the neoplastic cells scattered in fibrous stroma. The immunohistochemistry for endothelial tumor cells stained positive for Vimentin (+++), CD10 (+++), CD34 (++), CD31 (+), Factor VIII antigen (focal) (+) and low proliferative activity for ki-67. Our case is very interesting in which patient admitted with nonspecific symptoms of abdominal pain and diagnosed to be a Malignant Hepatic EHAE metastasized to the peritoneum, omentum and mesentery. The patient was on thalidomide 50 mg/day and increased to 100 mg/day. 5-Flurouracil (FU) intraperitoneal chemotherapy and other symptomatic and supportive treatment was given to the patient. Our case highlights on the importance of immunohistopathological diagnosis, compare the radiological findings of this disease and discuss the treatment strategy with review of available literature.

Omentum ECM-based hydrogel as a platform for cardiac cell delivery.

Cardiovascular diseases remain the number one killer in Western countries. Despite recent advances and promising results in cardiac cell-based therapy, one of the remaining challenges is poor cell retention in the desired site. As a solution, cell delivery systems are developed to ensure that a sufficient number of viable cells reach the infarct area. These delivery systems are based on biomaterials that provide a surrogate microenvironment for the encapsulated cells, retaining them in the desired location post-delivery. Injectable thermoresponsive ECM-based hydrogels have been developed to achieve this goal. Unfortunately, the use of allogeneic or xenogeneic ECM may hamper the treatment due to an immune response to residual cellular content from the host. In this work, we have developed an omentum-based hydrogel capable of self-assembly under physiological conditions. Although in this study the omentum was obtained from porcine sources, it can be easily and safely extracted from the patient, serving as an autologous protective vehicle for the transported cells. We have characterized the biochemical composition, mechanical properties, and gelation and degradation kinetics of the processed biomaterial. Furthermore, the ability of the hydrogel to encapsulate cardiac cells and support their culture was evaluated. We envision that the newly developed platform may open new opportunities for personalized cell delivery to the heart and other tissues.

Persistent organic pollutants (POPs) and fibroids: results from the ENDO study.

To evaluate the association between persistent organic pollutants (POPs) and uterine fibroids, we used previously collected data from a cohort of women aged 18-44 years undergoing laparoscopy or laparotomy at 14 participating hospital surgical centers (n=473). POP concentrations were measured in omental fat and serum. Presence of fibroids was defined on the basis of a postoperative diagnosis (n=99). Odds ratios (OR) and 95% confidence interval (CI) for each POP by biologic medium were estimated using unconditional logistic regression adjusted for identified covariates. Concentrations were higher in omental fat than in serum for all POPs. Serum p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) was the only POP associated with fibroids (per 1-SD increase in log-transformed p,p'-DDE OR (95% CI): 1.37 (1.05-1.80)). In analyses excluding women diagnosed with endometriosis, a number of polychlorinated biphenyls (PCBs) measured in omental fat were associated with fibroids (PCB 99: 1.64 (1.08, 2.49); PCB 138: 1.64 (1.03, 2.59); PCB 146: 1.54 (1.01, 2.37); PCB 153: 1.88 (1.12, 3.13); PCB 196: 1.60 (1.02, 2.51); PCB 206: 1.52 (1.01, 2.29)). Although exploratory, our study suggests that PCBs may be associated with fibroids in the absence of other gynecologic disorders such as endometriosis, but the associations varied by biologic media with more POPs emerging when quantified in fat.

Optimizing the biofabrication process of omentum-based scaffolds for engineering autologous tissues.

Omentum-based matrices fabricated by decellularization have the potential to serve as autologous scaffolds for tissue engineering. Transplantation of such scaffolds prepared from the patient's own biomaterial may reduce the immunogenic response after transplantation. Recently we reported on the potential of the decellularized omentum to support the assembly of functional vascularized cardiac patches. Here we compared five distinct protocols for omentum decellularization, utilizing chemical, physical and biological processes. We analyzed the efficiency of cell removal, scaffold macro and micro structure, biochemical composition and the ability of seeded cells to attach and proliferate in the matrix. Moreover, we assessed the ability of the distinct scaffolds to promote the organization of cardiac tissue.

Expression and prognostic significance of the polymeric immunoglobulin receptor in epithelial ovarian cancer.

BACKGROUND: High expression of the polymeric immunoglobulin receptor (PIGR) has previously been associated with a favourable prognosis in a few cancer forms, but its expression and relationship with clinical outcome in epithelial ovarian cancer (EOC) has not yet been reported. The aim of this study was therefore to examine the clinicopathological correlates and prognostic significance of PIGR expression in EOC. METHODS: After an initial screening in the Human Protein Atlas portal, a validated antibody was selected for extended analysis of immunohistochemical PIGR expression in tissue microarrays with tumours from 154 incident cases of EOC from two pooled prospective population-based cohorts. Subsets of corresponding benign-appearing fallopian tubes (n = 38) and omental metastases (n = 33) were also analysed. Kaplan-Meier analysis and Cox regression analysis were applied to examine the impact of PIGR expression on overall survival (OS) and ovarian cancer-specific survival (OCSS). RESULTS: PIGR expression was significantly higher in fallopian tubes compared to primary tumours and metastases (p < 0.001) and lower in carcinoma of the serous subtype compared to other carcinomas (p < 0.001). PIGR expression was significantly associated with lower grade (p = 0.001), mucinous histological subtype (p = 0.002), positive progesterone receptor expression (p = 0.009) and negative or low Ki-67 expression (p = 0.003). Kaplan-Meier analysis revealed a significantly improved OS (p = 0.013) and OCSS (p = 0.009) for patients with tumours displaying high expression of PIGR. These associations were confirmed in unadjusted Cox regression analysis (HR = 0.48; 95% CI 0.26-0.87; p = 0.015 for OS and HR = 0.43, 95% CI 0.22-0.82; p = 0.011 for OCSS) but did not remain significant after adjustment for age, grade and clinical stage. CONCLUSIONS: This study provides a first demonstration of PIGR expression in human fallopian tubes, primary EOC tumours and metastases. High tumour-specific expression of PIGR was found to be associated with a favourable prognosis in unadjusted, but not in adjusted, analysis. These findings are novel and merit further investigation.

Diffuse large B-cell lymphoma of the uterus suspected of having transformed from a marginal zone B-cell lymphoma harboring trisomy 18: a case report and review of the literature.

The patient was a 72-year-old female with the chief complaint of abdominal fullness. A giant primary myoma of the uterine cervix was suspected, and total hysterectomy was performed. Based on a postoperative histopathological examination of the tumor a diagnosis of diffuse large B-cell lymphoma (DLBCL) was made in the uterus and a mass in the greater omentum was diagnosed as a marginal zone B-cell lymphoma (MZBCL). No flow-cytometry studies or chromosome or gene examinations were performed on a fresh specimen. The results of an examination of a paraffin block histopathology specimen by fluorescence in-situ hybridization (FISH) showed no mucosa associated lymphoid tissue lymphoma translocation gene 1 (MALT1) (18q21.1), B-cell lymphoma 2 (BCL2) (18q21.3), or BCL6 (3q27) split signals in either the uterus or the greater omentum, however, trisomy 18 was detected in approximately 50%-70% of the tumor cells in both the uterus and the greater omentum. Trisomy 18 was present in around 15-33% of the DLBCL cells and MZBCL cells. These findings suggested a strong possibility that the tumor cells in the uterus and greater omentum were the same clone and that transformation from MZBCL to DLBCL had occurred. Since DLBCLs that result from a transformation usually have a worse outcome than de novo DLBCLs, even when a DLBCL seems to have originated in the uterus the surrounding tissue should always be examined, and caution should be exercised in regard to transformation from a low-grade B-cell lymphoma to a DLBCL.

2D-DIGE to identify proteins associated with gestational diabetes in omental adipose tissue.

Gestational diabetes mellitus (GDM) is a significant risk factor for the type 2 diabetes epidemic in many populations. Maternal adipose tissue plays a central role in the pathophysiology of GDM. Thus, the aim of this study was to determine the effect of GDM on the proteome of adipose tissue. Omental adipose tissue was obtained at the time of term Caesarean section from women with normal glucose tolerance (NGT) or GDM. 2D-difference gel electrophoresis (DIGE), followed by mass spectrometry, was used to identify protein spots (n = 6 patients per group). Western blotting was used for confirmation of six of the spot differences (n = 6 patients per group). We found 14 proteins that were differentially expressed between NGT and GDM adipose tissue (≥ 1.4-fold, P < 0.05). GDM was associated with an up-regulation of four proteins: collagen alpha-2(VI) chain (CO6A2 (COL6A2)), fibrinogen beta chain (FIBB (FGB)), lumican (LUM) and S100A9. On the other hand, a total of ten proteins were found to be down-regulated in adipose tissue from GDM women. These were alpha-1-antitrypsin (AIAT (SERPINA 1)), annexin A5 (ANXA5), fatty acid-binding protein, adipocyte (FABP4), glutathione S-transferase P (GSTP (GSTP1)), heat-shock protein beta-1 (HSP27 (HSPB1)), lactate dehydrogenase B chain (LDHB), perilipin-1 (PLIN1), peroxiredoxin-6 (PRX6 (PRDX6)), selenium-binding protein 1 (SBP1) and vinculin (VINC (VCL)). In conclusion, proteomic analysis of omental fat reveals differential expression of several proteins in GDM patients and NGT pregnant women. This study revealed differences in expression of proteins that are involved in inflammation, lipid and glucose metabolism and oxidative stress and added further evidence to support the role of visceral adiposity in the pathogenesis of GDM.

Decellularized omentum as novel biologic scaffold for reconstructive surgery and regenerative medicine.

Homologous tissues, such as adipose tissue, may be an interesting source of acellular scaffolds, maintaining a complex physiological three-dimensional (3D) structure, to be recellularized with autologous cells. The aim of the present work is to evaluate the possibility of obtaining homologous acellular scaffolds from decellularization of the omentum, which is known to have a complex vascular network. Adult rat and human omenta were treated with an adapted decellularization protocol involving mechanical rupture (freeze-thaw cycles), enzymatic digestion (trypsin, lipase, deoxyribonuclease, ribonuclease) and lipid extraction (2-propanol). Histological staining confirmed the effectiveness of decellularization, resulting in cell-free scaffolds with no residual cells in the matrix. The complex 3D networks of collagen (azan-Mallory), elastic fibers (Van Gieson), reticular fibers and glycosaminoglycans (PAS) were maintained, whereas Oil Red and Sudan stains showed the loss of lipids in the decellularized tissue. The vascular structures in the tissue were still visible, with preservation of collagen and elastic wall components and loss of endothelial (anti-CD31 and -CD34 immunohistochemistry) and smooth muscle (anti-alpha smooth muscle actin) cells. Fat-rich and well vascularized omental tissue may be decellularized to obtain complex 3D scaffolds preserving tissue architecture potentially suitable for recellularization. Further analyses are necessary to verify the possibility of recolonization of the scaffold by adipose-derived stem cells in vitro and then in vivo after re-implantation, as already known for homologus implants in regenerative processes.

Fatty acid composition of adipose tissue and muscle from Jersey steers was affected by finishing diet and tissue location.

To determine the impacts of finishing diet and tissue type and location on fatty acid composition and palatability of Jersey beef, twenty steers were assigned to a factorial treatment design with initial weight (Light vs. Heavy) and finishing diet (70 vs. 85% concentrate) as treatments. Ribeye steaks were collected for sensory evaluation. Muscle, seam and subcutaneous (s.c.) fat from steaks, kidney fat (KF) and omental fat (OMF) were collected for fatty acid analysis. Initial weight and finishing diet had little impact on beef palatability. The 85% concentrate decreased polyunsaturated fatty acids (PUFA) in muscle and increased trans fatty acids in all tissues (P<0.05). The monounsaturated:saturated fatty acid ratio (MUFA:SFA) was highest in s.c. fat, intermediate in muscle and seam fat, and lowest in KF and OMF. The PUFA:SFA was highest in muscle, intermediate in s.c. and seam fat, and lowest in KF and OMF. Fatty acid composition differed greatly among tissues and the lower concentrate diet increased omega-3 and PUFA percentages in muscle.