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Acta Orthopaedica Et Traumatologica... Oct 2016The purpose of this study was to investigate the effects of the omentum, peritoneum, paratenon and skeletal muscle on the proliferation of the cartilage tissue using...
OBJECTIVE
The purpose of this study was to investigate the effects of the omentum, peritoneum, paratenon and skeletal muscle on the proliferation of the cartilage tissue using rabbit model as an in vivo culture medium.
METHODS
6 months old forty-five New Zealand rabbits were randomized into omentum, peritoneum, muscle, and Achilles paratenon groups. Standard sized osteochondral grafts were harvested from right knees and immediately placed into the specified tissues. Control group was fresh cartilage at the end of follow-up. After five months, samples were collected and evaluated macroscopically by measuring their dimensions (vertical = D1, horizontal = D2, and depth = D3) and volumes, and histologically by counting the chondrocyte number using camera lucida method.
RESULTS
Macroscopically, increase in mean values for D1 and D2 dimensions of specimens from paratenon and omentum compared to pretransplant dimensions was statistically significant (p < 0.05). Although, volume measurements were higher in omentum and peritoneum group compared to pretransplant dimensions, increase was not significant (p > 0.05). Histologically, mean chondrocyte count was 14.0 ± 0.6 in fresh articular cartilage. Mean chondrocyte counts were 14.4 ± 0.9 in omentum group, 15.4 ± 1.0 in peritoneum group, 9.7 ± 1.3 in muscle group and 9.2 ± 0.4 in Achilles paratenon group respectively. However, mean chondrocyte counts were higher in samples of omentum and peritoneum group compared to fresh articular cartilage, increase was not statistically significant (p > 0.05).
DISCUSSION
Transplantation of the cartilage grafts into mesothelium enhanced the chondrocyte counts and volumes compared with the pretransplant measurements. Mesothelium may have the potential to be used as an in vivo culture medium for osteochondral tissue growth.
Topics: Animals; Cartilage, Articular; Chondrocytes; Male; Omentum; Peritoneum; Rabbits; Random Allocation; Tissue Preservation; Transplantation, Autologous
PubMed: 27717559
DOI: 10.1016/j.aott.2016.08.003 -
Cells Jan 2022B1 cells constitute a specialized subset of B cells, best characterized in mice, which is abundant in body cavities, including the peritoneal cavity. Through natural and...
B1 cells constitute a specialized subset of B cells, best characterized in mice, which is abundant in body cavities, including the peritoneal cavity. Through natural and antigen-induced antibody production, B1 cells participate in the early defense against bacteria. The G protein-coupled receptor 183 (GPR183), also known as Epstein-Barr virus-induced gene 2 (EBI2), is an oxysterol-activated chemotactic receptor that regulates migration of B cells. We investigated the role of GPR183 in B1 cells in the peritoneal cavity and omentum. B1 cells expressed GPR183 at the mRNA level and migrated towards the GPR183 ligand 7α,25-dihydroxycholesterol (7α,25-OHC). GPR183 knock-out (KO) mice had smaller omenta, but with normal numbers of B1 cells, whereas they had fewer B2 cells in the omentum and peritoneal cavity than wildtype (WT) mice. GPR183 was not responsible for B1 cell accumulation in the omentum in response to i.p. lipopolysaccharide (LPS)-injection, in spite of a massive increase in 7α,25-OHC levels. Lack of GPR183 also did not affect B1a- or B1b cell-specific antibody responses after vaccination. In conclusion, we found that GPR183 is non-essential for the accumulation and function of B1 cells in the omentum and peritoneal cavity, but that it influences the abundance of B2 cells in these compartments.
Topics: Animals; B-Lymphocyte Subsets; Epstein-Barr Virus Infections; Herpesvirus 4, Human; Hydroxycholesterols; Mice; Mice, Knockout; Omentum; Peritoneal Cavity; Receptors, G-Protein-Coupled
PubMed: 35159303
DOI: 10.3390/cells11030494 -
The Journal of Experimental Medicine Jan 2019In this issue of , Lee et al. (https://doi.org/10.1084/jem.20181170) provide evidence to show that early influx of neutrophils into omentum represents a key mechanism in...
In this issue of , Lee et al. (https://doi.org/10.1084/jem.20181170) provide evidence to show that early influx of neutrophils into omentum represents a key mechanism in establishing the premetastatic niche for the subsequent implantation of ovarian cancer cells at this site.
Topics: Female; Fertilizers; Humans; Neutrophils; Omentum; Ovarian Neoplasms
PubMed: 30567720
DOI: 10.1084/jem.20182059 -
BMJ Case Reports Feb 2012A middle-aged-woman presented with symptoms and signs of acute abdomen. Clinically a suspicion of acute appendicitis was raised, although the abdominal x-ray and...
A middle-aged-woman presented with symptoms and signs of acute abdomen. Clinically a suspicion of acute appendicitis was raised, although the abdominal x-ray and ultrasound were normal. She was managed conservatively, which she failed to respond. In the view of persisting pain, a contrast enhanced CT (CECT) was done. CECT showed a whirling mass of fatty and fibrous tissue adherent to the anterior abdominal wall suggestive of omental torsion and the diagnosis was confirmed on laparotomy and she underwent excision of the ischaemic omentum. Omental torsion though rare, should be included in the differential diagnosis of acute abdomen. High index of suspicion is required to diagnose this entity. CECT abdomen shows the classical finding of fatty mass with whirling pattern. It is seldom considered in the differential diagnosis preoperatively based on clinical findings and the diagnosis is only established during the surgical procedure.
Topics: Abdomen, Acute; Female; Humans; Middle Aged; Omentum; Peritoneal Diseases; Tomography, X-Ray Computed; Torsion Abnormality
PubMed: 22665571
DOI: 10.1136/bcr.12.2011.5447 -
Rhode Island Medical Journal (2013) Aug 2021
Topics: Humans; Omentum; Peritoneal Neoplasms
PubMed: 34323874
DOI: No ID Found -
The Journal of Steroid Biochemistry and... Apr 2015Epithelial ovarian cancer (EOC) is the leading cause of gynecological cancer death in women, mainly because it has spread to intraperitoneal tissues such as the omentum... (Review)
Review
Epithelial ovarian cancer (EOC) is the leading cause of gynecological cancer death in women, mainly because it has spread to intraperitoneal tissues such as the omentum in the peritoneal cavity by the time of diagnosis. In the present study, we established in vitro assays, ex vivo omental organ culture system and syngeneic animal tumor models using wild type (WT) and vitamin D receptor (VDR) null mice to investigate the effects of 1α,25-dihydroxyvitamin D3 (1,25D3) and VDR on EOC invasion. Treatment of human EOC cells with 1,25D3 suppressed their migration and invasion in monolayer scratch and transwell assays and ability to colonize the omentum in the ex vivo system, supporting a role for epithelial VDR in interfering with EOC invasion. Furthermore, VDR knockdown in OVCAR3 cells increased their ability to colonize the omentum in the ex vivo system in the absence of 1,25D3, showing a potential ligand-independent suppression of EOC invasion by epithelial VDR. In syngeneic models, ID8 tumors exhibited an increased ability to colonize omenta of VDR null over that of WT mice; pre-treatment of WT, not VDR null, mice with EB1089 reduced ID8 colonization, revealing a role for stromal VDR in suppressing EOC invasion. These studies are the first to demonstrate a role for epithelial and stromal VDR in mediating the activity of 1,25D3 as well as a 1,25D3-independent action of the VDR in suppressing EOC invasion. The data suggest that VDR-based drug discovery may lead to the development of new intervention strategies to improve the survival of patients with EOC at advanced stages. This article is part of a Special Issue entitled "Vitamin D Workshop".
Topics: Animals; Calcitriol; Carcinoma, Ovarian Epithelial; Female; Humans; Mice; Neoplasm Invasiveness; Neoplasms, Glandular and Epithelial; Omentum; Ovarian Neoplasms; Receptors, Calcitriol; Vitamins
PubMed: 25448740
DOI: 10.1016/j.jsbmb.2014.11.005 -
American Journal of Transplantation :... Nov 2016Transplantation of islets into the liver confers several site-specific challenges, including a delayed vascularization and prevailing hypoxia. The greater omentum has in...
Rapid Restoration of Vascularity and Oxygenation in Mouse and Human Islets Transplanted to Omentum May Contribute to Their Superior Function Compared to Intraportally Transplanted Islets.
Transplantation of islets into the liver confers several site-specific challenges, including a delayed vascularization and prevailing hypoxia. The greater omentum has in several experimental studies been suggested as an alternative implantation site for clinical use, but there has been no direct functional comparison to the liver. In this experimental study in mice, we characterized the engraftment of mouse and human islets in the omentum and compared engraftment and functional outcome with those in the intraportal site. The vascularization and innervation of the islets transplanted into the omentum were restored within the first month by paralleled ingrowth of capillaries and nerves. The hypoxic conditions in the islets early posttransplantation were transient and restricted to the first days. Newly formed blood vessels were fully functional, and the blood perfusion and oxygenation of the islets became similar to that of endogenous islets. Furthermore, islet grafts in the omentum showed at 1 month posttransplantation functional superiority to intraportally transplanted grafts. We conclude that in contrast to the liver the omentum provides excellent engraftment conditions for transplanted islets. Future studies in humans will be of great interest to investigate the capability of this site to also harbor larger grafts without interfering with islet functionality.
Topics: Animals; Female; Graft Survival; Humans; Islets of Langerhans; Islets of Langerhans Transplantation; Liver; Male; Mice; Mice, Inbred C57BL; Mice, Nude; Middle Aged; Neovascularization, Physiologic; Omentum; Oxygen
PubMed: 27321369
DOI: 10.1111/ajt.13927 -
BMC Surgery May 2018Spontaneous rupture of omental vessels is an infrequent medical condition possibly causing severe intra-abdominal hemorrhage. Omental bleeding results from trauma... (Review)
Review
BACKGROUND
Spontaneous rupture of omental vessels is an infrequent medical condition possibly causing severe intra-abdominal hemorrhage. Omental bleeding results from trauma associated injury and irritation, neoplasia, arterial aneurysm rupture, and anticoagulant treatment. Idiopathic omental bleeding rarely causes acute abdominal bleeding which has been reported to occur in previous studies. Here we reported a case with idiopathic omental hemorrhage due to vascular malformation. A systematic review of literature is provided.
CASE PRESENTATION
A 58-year-old Han Chinese man arrived at the emergency department with left upper quadrant abdominal pain for 1 day. He had no significant previous medical history. There was no history of fever, vomiting, nausea, or anorexia. He was a non-smoker and did not consume alcohol. On physical examination, blood pressure was 118/72 mmHg, for a temperature of 37.7 °C; heart and respiratory rates of 130 per/min and 20 per/min were obtained, respectively. Abdomen assessment showed only mild tenderness in the left upper quadrant. Complete blood count (CBC) showed white cell and platelet counts of 16.69 × 10/L and 196 × 10/L, respectively. The haemoglobin value was 13.5 g/L at admission. Abdominal Computer Tomography (CT) was performed that showed peritoneal fluid appeared around the liver. Fresh blood was confirmed in the abdominocentesis. A hemoperitoneum was confirmed by abdominal enhanced CT, which presented a structural disorder in the left upper abdomen. The subject immediately underwent exploratory laparotomy. A massive hemoperitoneum originating from omental vessels was observed. The omental were partially removed. There was no evidence of malignancy or aneurysm upon palpation. Pathological assessment of the extracted tissue pointed to vascular malformation. The patient subsequently had an uneventful recovery; hospital discharge occurred at 7 days post-operation. Previous reports assessing idiopathic omental bleeding were systematically reviewed, summarizing published cases. A total of 12 hits were found in PubMed for idiopathic omental bleeding.
CONCLUSION
Idiopathic omental bleeding is a rare condition that requires emergency treatment. Treatment strategies include surgical intervention and transcatheter arterial embolization (TAE). The surgical option is suitable in subjects with persistent hypotension and those with unconfirmed diagnosis.
Topics: Abdominal Pain; Embolization, Therapeutic; Emergency Service, Hospital; Hemoperitoneum; Humans; Laparotomy; Male; Middle Aged; Omentum; Rupture, Spontaneous; Tomography, X-Ray Computed; Vomiting
PubMed: 29848342
DOI: 10.1186/s12893-018-0364-9 -
Tidsskrift For Den Norske Laegeforening... Apr 2013
Topics: Abdominal Pain; Adult; Female; Humans; Omentum; Peritoneal Diseases; Tomography, X-Ray Computed; Torsion Abnormality
PubMed: 23612108
DOI: 10.4045/tidsskr.12.1301 -
Circulation Research Feb 2022The chromatin-remodeling enzyme BRG1 (brahma-related gene 1) regulates gene expression in a variety of rapidly differentiating cells during embryonic development....
BACKGROUND
The chromatin-remodeling enzyme BRG1 (brahma-related gene 1) regulates gene expression in a variety of rapidly differentiating cells during embryonic development. However, the critical genes that BRG1 regulates during lymphatic vascular development are unknown.
METHODS
We used genetic and imaging techniques to define the role of BRG1 in murine embryonic lymphatic development, although this approach inadvertently expanded our study to multiple interacting cell types.
RESULTS
We found that omental macrophages fine-tune an unexpected developmental process by which erythrocytes escaping from naturally discontinuous omental blood vessels are collected by nearby lymphatic vessels. Our data indicate that circulating fibrin(ogen) leaking from gaps in omental blood vessels can trigger inflammasome-mediated IL-1β (interleukin-1β) production and secretion from nearby macrophages. IL-1β destabilizes adherens junctions in omental blood and lymphatic vessels, contributing to both extravasation of erythrocytes and their uptake by lymphatics. BRG1 regulates IL-1β production in omental macrophages by transcriptionally suppressing the inflammasome trigger RIPK3 (receptor interacting protein kinase 3).
CONCLUSIONS
Genetic deletion of in embryonic macrophages leads to excessive IL-1β production, erythrocyte leakage from blood vessels, and blood-filled lymphatics in the developing omentum. Altogether, these results highlight a novel context for epigenetically regulated crosstalk between macrophages, blood vessels, and lymphatics.
Topics: Adherens Junctions; Animals; Blood Vessels; DNA Helicases; Erythrocytes; Inflammasomes; Interleukin-1beta; Lymphatic Vessels; Macrophages; Mice; Mice, Inbred C57BL; Nuclear Proteins; Omentum; Transcription Factors
PubMed: 34986653
DOI: 10.1161/CIRCRESAHA.121.319032