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The Heart Surgery Forum Oct 2017We read with great interest the report by Dr. Colak and coworkers about utilization of omentoplasty in poststernotomy mediastinitis treatment [Colak 2016]. In our...
We read with great interest the report by Dr. Colak and coworkers about utilization of omentoplasty in poststernotomy mediastinitis treatment [Colak 2016]. In our opinion, several points need to be addressed.
Topics: Cardiac Surgical Procedures; Debridement; Humans; Mediastinitis; Omentum; Plastic Surgery Procedures; Sternum; Surgical Flaps; Surgical Wound Infection
PubMed: 29087288
DOI: 10.1532/hsf.1907 -
Journal of Investigative Medicine : the... Oct 2010In type 1 diabetes, the β-cells that secrete insulin have been destroyed such that daily exogenous insulin administration is required for the control of blood glucose...
INTRODUCTION
In type 1 diabetes, the β-cells that secrete insulin have been destroyed such that daily exogenous insulin administration is required for the control of blood glucose in individuals with the disease. After the development of reliable techniques for the isolation of islets from the human pancreas, islet transplantation has emerged as a therapeutic option, albeit for only a few selected patients largely because there are not enough islets for the millions of patients requiring the treatment, and there is also the need to use immunosuppressive drugs to prevent transplant rejection. In 1980, the concept of islet immunoisolation by microencapsulation was introduced as a technique to overcome these 2 major barriers to islet transplantation. Microencapsulation of islets and transplantation in the peritoneal cavity was then described as a bioartificial pancreas. However, it is difficult to retrieve encapsulated islets transplanted in the peritoneal cavity, thus making it difficult to meet all the criteria for a bioartificial pancreas. A new design of a bioartificial pancreas comprising islets co-encapsulated with angiogenic protein in permselective multilayer alginate-poly-L-ornithine-alginate microcapsules and transplanted in an omentum pouch is described in this paper.
MATERIALS AND METHODS
The multilayer alginate-poly-L-ornithine-alginate microcapsules are made with ultrapure alginate using poly-L-ornithine as a semipermeable membrane separating the 2 alginate layers. The inner alginate layer is used to encapsulate the islets, and the outer layer is used to encapsulate angiogenic protein, which would induce neovascularization around the graft within the omentum pouch.
RESULTS
In in vitro studies, we found that both the wild-type and the heparin-binding growth-associated molecule (HBGAM)-fibroblast growth factor-1 chimera can be encapsulated and released in a controlled and sustained manner from the outer alginate layer with a mean diameter in the range of 113 to 164 µm when 1.25% high guluronic acid alginate is used to formulate this outer layer.
DISCUSSION
We are currently performing in vivo experiments to determine the ability of angiogenic proteins released from this outer layer to induce neovascularization around the grafts in the omentum pouch. We will subsequently examine the effect of co-encapsulation of islets with angiogenic protein on blood glucose control in diabetic animals. It is hoped that addition of tissue engineering to encapsulated islet transplantation will result in long-term survival of the islets and their ability to control blood glucose in type 1 diabetes without the necessity to use risky immunosuppressive drugs to prevent transplant rejection.
Topics: Alginates; Animals; Diabetes Mellitus, Type 1; Humans; Islets of Langerhans Transplantation; Microspheres; Omentum; Pancreas, Artificial; Polylysine; Tissue Engineering
PubMed: 20683347
DOI: 10.231/JIM.0b013e3181ed3807 -
Journal of the American Society of... Jun 2014Stem cells show promise in the treatment of AKI but do not survive long term after injection. However, organ repair has been achieved by extending and attaching the...
Stem cells show promise in the treatment of AKI but do not survive long term after injection. However, organ repair has been achieved by extending and attaching the omentum, a fatty tissue lying above the stomach containing stem cells, to various organs. To examine whether fusing the omentum to a subtotally nephrectomized kidney could slow the progression of CKD, we used two groups of rats: an experimental group undergoing 5/6 nephrectomy only and a control group undergoing 5/6 nephrectomy and complete omentectomy. Polydextran gel particles were administered intraperitoneally before suture only in the experimental group to facilitate the fusion of the omentum to the injured kidney. After 12 weeks, experimental rats exhibited omentum fused to the remnant kidney and had lower plasma creatinine and urea nitrogen levels; less glomerulosclerosis, tubulointerstitial injury, and extracellular matrix; and reduced thickening of basement membranes compared with controls. A fusion zone formed between the injured kidney and the omentum contained abundant stem cells expressing stem cell antigen-1, Wilms' tumor 1 (WT-1), and CD34, suggesting active, healing tissue. Furthermore, kidney extracts from experimental rats showed increases in expression levels of growth factors involved in renal repair, the number of proliferating cells, especially at the injured edge, the number of WT-1-positive cells in the glomeruli, and WT-1 gene expression. These results suggest that contact between the omentum and injured kidney slows the progression of CKD in the remnant organ, and this effect appears to be mediated by the presence of omental stem cells and their secretory products.
Topics: Adipose Tissue; Adult Stem Cells; Animals; Cell Proliferation; Disease Models, Animal; Disease Progression; Glomerular Mesangium; Glomerulosclerosis, Focal Segmental; Intercellular Signaling Peptides and Proteins; Male; Nephrectomy; Omentum; Paracrine Communication; Rats; Rats, Sprague-Dawley; Renal Insufficiency, Chronic
PubMed: 24627352
DOI: 10.1681/ASN.2013040387 -
The Journal of Clinical Endocrinology... Feb 2022Adipose tissue distribution is a key factor influencing metabolic health and risk in obesity-associated comorbidities. (Observational Study)
Observational Study
CONTEXT
Adipose tissue distribution is a key factor influencing metabolic health and risk in obesity-associated comorbidities.
OBJECTIVE
Here we aim to compare the proteomic profiles of mature adipocytes from different depots.
METHODS
Abdominal subcutaneous (SA) and omental visceral adipocytes (VA) were isolated from paired adipose tissue biopsies obtained during bariatric surgery on 19 severely obese women (body mass index > 30 kg/m2) and analyzed using state-of-the-art mass spectrometry. Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were performed to investigate proteome signature properties and to examine a possible association of the protein expression with the clinical data.
RESULTS
We identified 3686 protein groups and found 1140 differentially expressed proteins (adj. P value < 0.05), of which 576 proteins were upregulated in SA and 564 in VA samples. We provide a global protein profile of abdominal SA and omental VA, present the most differentially expressed pathways and processes distinguishing SA from VA, and correlate them with clinical and body composition data. We show that SA are significantly more active in processes linked to vesicular transport and secretion, and to increased lipid metabolism activity. Conversely, the expression of proteins involved in the mitochondrial energy metabolism and translational or biosynthetic activity is higher in VA.
CONCLUSION
Our analysis represents a valuable resource of protein expression profiles in abdominal SA and omental VA, highlighting key differences in their role in obesity.
Topics: Adipocytes; Adult; Bariatric Surgery; Female; Gene Regulatory Networks; Humans; Intra-Abdominal Fat; Middle Aged; Obesity, Morbid; Omentum; Proteomics; Subcutaneous Fat, Abdominal
PubMed: 34669916
DOI: 10.1210/clinem/dgab756 -
Journal of Medical Case Reports Jun 2023Omental Infarction (OI) is uncommon and mimics common causes of acute abdomen. It is important to differentiate it from other abdominal conditions that require emergency...
BACKGROUND
Omental Infarction (OI) is uncommon and mimics common causes of acute abdomen. It is important to differentiate it from other abdominal conditions that require emergency management. It was first reported in literature in 1896 and about 400 cases have been reported till date.
CASE PRESENTATION
We reported on a 41 year-old Para 0 Ibo house wife who presented with 10 years history of supra-pubic mass and five months history of excessive menstrual flow. After physical examination, a diagnosis of symptomatic uterine fibroid was made. She had myomectomy and the raw surface created after the excision of the myomas was covered with omentum. Wound infection developed on the 8th post-operative day leading to a wound breakdown and later partial extrusion of infarcted omental tissue through the dehisced wound. During re-exploration, the infarcted omental tissue was extracted and the residual abdominal abscess was drained. Surgical site wound infection occurred on the 3rd day after re-operation and a sub-acute intestinal obstruction developed on the 4th day thereafter which responded to conservative management.
CONCLUSION
Careful surgical technique is imperative when utilizing the omentum for reconstructive abdominal surgery. Torsion of the omentum and creation of excess tension while using the omentum for reconstructive procedures should be avoided and increase awareness of this uncommon disease condition by the surgeon is also important. This case is to report a rare finding of omental infarction following myomectomy.
Topics: Female; Humans; Adult; Uterine Myomectomy; Peritoneal Diseases; Abdomen, Acute; Diagnosis, Differential; Omentum; Infarction
PubMed: 37337268
DOI: 10.1186/s13256-023-03924-y -
BMJ Open Gastroenterology May 2022To evaluate the feasibility and diagnostic performance of acoustic radiation force impulse (ARFI) elastography in different omental masses (OM).
OBJECTIVE
To evaluate the feasibility and diagnostic performance of acoustic radiation force impulse (ARFI) elastography in different omental masses (OM).
DESIGN
This was a retrospective analysis of 106 patients with OM defined as omental thickness ≥1 cm, who underwent abdominal B-mode ultrasound (US) and standardised ARFI examinations of the OM between September 2018 and June 2021 at our university hospital. A cytohistological confirmation was available in 91/106 (85.8%) of all OM, including all 65/65 (100%) malignant OM (mOM) and 26/41 (63.4%) of benign OM (bOM). In 15/41 (36.6%) of bOM; cross-sectional imaging and or US follow-up with a mean duration of 19.8±3.1 months was performed. To examine the mean ARFI velocities (MAV) for potential cut-off values between bOM and mOM a receiver operating characteristic analysis was implemented.
RESULTS
The MAV in the mOM group (2.71±1.04 m/s) was significantly higher than that of bOM group (1.27±0.87 m/s) (p<0.001). Using 1.97 m/s as a cut-off yielded a sensitivity and specificity of 76.9% and 85.4%, respectively, in diagnosing mOM (area under the curve=0.851, 95% CI=0.774 to 0.928).
CONCLUSION
ARFI elastography is feasible in the omentum and may represent a good non-invasive additional tool in differentiating bOM from mOM.
Topics: Diagnosis, Differential; Elasticity Imaging Techniques; Feasibility Studies; Humans; Omentum; Retrospective Studies
PubMed: 35523459
DOI: 10.1136/bmjgast-2022-000901 -
Internal Medicine (Tokyo, Japan) 2015
Topics: Adult; Four-Dimensional Computed Tomography; Hernia; Herniorrhaphy; Humans; Male; Omentum; Recurrence; Scrotum; Treatment Outcome
PubMed: 25786471
DOI: 10.2169/internalmedicine.54.3894 -
cDC1 coordinate innate and adaptive responses in the omentum required for T cell priming and memory.Science Immunology Sep 2022In the peritoneal cavity, the omentum contains fat-associated lymphoid clusters (FALCs) whose role in response to infection is poorly understood. After intraperitoneal...
In the peritoneal cavity, the omentum contains fat-associated lymphoid clusters (FALCs) whose role in response to infection is poorly understood. After intraperitoneal immunization with , conventional type 1 dendritic cells (cDC1s) were critical to induce innate sources of IFN-γ and cellular changes in the FALCs. Unexpectedly, infected peritoneal macrophages that migrated into the FALCs primed CD8 T cells. Although T cell priming was cDC1 independent, these DCs were required for maximal CD8 T cell expansion. An agent-based computational model and experimental data highlighted that cDC1s affected the magnitude of the proliferative burst and promoted CD8 T cell expression of nutrient uptake receptors and cell survival. Thus, although FALCs lack the organization of secondary lymphoid organs, cDC1s resident in this tissue coordinate innate responses to microbial challenge and provide secondary signals required for T cell expansion and memory formation.
Topics: CD8-Positive T-Lymphocytes; Dendritic Cells; Omentum
PubMed: 36179012
DOI: 10.1126/sciimmunol.abq7432 -
Asian Journal of Surgery Jan 2020Etiology of ascites of unknown origin varies with geographic area and ethnic origin. Tuberculous peritonitis and peritoneal carcinomatosis constitute a considerable... (Review)
Review
Etiology of ascites of unknown origin varies with geographic area and ethnic origin. Tuberculous peritonitis and peritoneal carcinomatosis constitute a considerable proportion of patients. Differentiation between both is a major challenge. The role of omental thickness (OT) by ultrasonography to predict risk of malignancy in unexplained ascites. This prospective study was done at Kasr Alainy School of Medicine, Cairo University and included 100 adults with unexplained ascites and thickened omentum (>15 mm) on ultrasonography. An expert performed ultrasonography to assess peritoneum and peritoneal cavity and measure OT. Ascites was assessed regarding volume, echogenicity, and loculation. The ascitic fluid was analyzed to measure lactate dehydrogenase, adenosine deaminase, and total leukocytic count. Laparoscopic exploration with biopsy was done for final diagnosis that divided the patients into; TB Group (n = 44) and peritoneal carcinomatosis group (n = 56). Main Outcome Measures were to determine degree of omental thickness as a predictor of malignancy risk in unexplained ascites and other ultrasonographic features to predict malignancy risk including omental echogenicity and results of diagnostic ascitic tapping. We found that OT was greater in the PC group compared to the TB group (24.6 ± 4.6 mm vs. 17.9 ± 3.0 mm, respectively, p < 0.001). Higher frequency of hypoechogenicity, irregular peritoneal surface, omental cakes, and lymph nodes was seen in PC Group. ADA, TLC, and relative lymphocyte count were higher in TB group. Omental thickness ≥19.5 mm has a sensitivity of 89.3%, specificity of 84.1% to diagnose PC. We can conclude that omental thickness >19 mm is a sensitive and specific predictor of malignancy in patients with unexplained ascites.
Topics: Aged; Ascites; Egypt; Female; Humans; Male; Middle Aged; Omentum; Predictive Value of Tests; Risk; Ultrasonography
PubMed: 30910377
DOI: 10.1016/j.asjsur.2019.03.004 -
Tumour Biology : the Journal of the... May 2016As the most common metastatic disease of abdomen pelvic cavity cancer, peritoneal carcinomatosis (PC) renders significant negative impact on patient survival and quality... (Review)
Review
As the most common metastatic disease of abdomen pelvic cavity cancer, peritoneal carcinomatosis (PC) renders significant negative impact on patient survival and quality of life. Invasive peritoneal exfoliated cancer cells (PECCs) preferentially select the omentum as a predominant target site for cancer cell colonization and proliferation compared with other tissues in the abdominal cavity. The precise pathogenic mechanism remains to be determined. As omental milky spots (MSs) are the major implantation site for malignant cells in peritoneal dissemination, researches on mechanisms of PC have been mainly focused on MS, primitive lymphoid tissues with unique structural features, and functional characteristics. To date, extensive biophysical and biochemical methods have been manipulated to investigate the MS exact function in the peritoneal cavity. This review summarized MS as hotbeds for PECC. The anatomical distribution was briefly described first. Then, MS histology was systematically reviewed, including morphological features, cellular constituents, and histological staining methods. At last, the roles of MS in PC pathological process were summarized with special emphasis on the distinct roles of macrophages.
Topics: Animals; Carcinoma; Cell Movement; Humans; Lymphocytes; Lymphoid Tissue; Macrophages, Peritoneal; Omentum; Organ Specificity; Peritoneal Neoplasms; Pleura; Staining and Labeling
PubMed: 26831659
DOI: 10.1007/s13277-016-4887-3