The peritoneal cavity is a distinct compartment of angiogenic molecular mediators

Fascia Lata Grafting Combined with Gluteal Flaps for Pelvic Floor Reconstruction after Oncologic Resection

Although recent methods of pelvic reconstruction using myocutaneous flaps have reduced postoperative morbidities' including pelvic abscess, the complication rates are still high due to the presence of a large dead cavity and poorly vascularized tissues secondary to preoperative chemoradiation therapy. We aimed to evaluate the usefulness and benefit of fascia lata autografting for pelvic floor reconstruction as a supplemental procedure for gluteal flap closure of perineal wounds.

Methods

Our retrospective study included 144 consecutive patients who underwent rectal cancer resection with or without pelvic reconstruction, from 2010 to 2020. For reconstruction, fascia lata autografts were harvested from the thigh and affixed to the pelvic floor. The perineal wound was closed using gluteal advancement flaps.

Results

The study included 33 reconstructed and 111 nonreconstructed patients (average age: 69.5 years). The reconstructed group was more likely to have undergone preoperative chemotherapy (81.8% versus 40.5%, P < 0.001) and radiotherapy (78.8% versus 48.6%, P = 0.002), compared with the nonreconstructed group. Additionally, the reconstructed group underwent fewer abdominoperineal resections (63.6% versus 94.6%, P < 0.001) and more pelvic exenterations (36.4% versus 5.4%). The mean size of fascia lata autografts was 8.3 × 5.9 cm. There were significant differences between the reconstructed and nonreconstructed groups, in the incidences of complications (15.2% versus 33.3%, P = 0.044) and pelvic abscess (3.0% versus 16.2%, P = 0.049).

Conclusion

Combination of fascia lata autografts and gluteal flaps is considered an effective method of pelvic reconstruction for its low incidence of complications and stable outcomes.

Lymphocyte integrin expression differences between SIRS and sepsis patients

BACKGROUND

Systemic Inflammatory Response Syndrome (SIRS) and sepsis remain leading causes of death. Despite many similarities, the two entities are very distinct clinically and immunologically. T-Lymphocytes play a key pivotal role in the pathogenesis and ultimately outcome following both SIRS and sepsis. Integrins are essential in the trafficking and migration of lymphocytes. They also serve vital roles in efficient wound healing and clearance of infections. Here, we investigate whether integrin expression, specifically β1 (CD29) and β2 (CD18), are disrupted in SIRS and sepsis, and assess differences in integrin expression between these two critically ill clinical categories.

METHODS

T-Lymphocytes were isolated from whole blood collected from ICU patients exhibiting SIRS or sepsis. Samples were analyzed for CD18 (β2) and CD29 (β1) on CD3⁺ T cells through flow cytometry. Septic patients were stratified into either exclusively abdominal or non-abdominal sources of sepsis.

RESULTS

CD18 was almost ubiquitously expressed on CD3⁺ T cells irrespective of clinical condition. However, CD29 (β1 integrin) was lowest in SIRS patients (20.4% of CD3⁺ T cells) when compared with either septic patients (35.5%) or healthy volunteers (54.1%). Furthermore, there was evidence of compartmentalization in septic patients, where abdominal sources had a greater percentage of CD3⁺CD29⁺ T cells (41.7%) when compared with those with non-abdominal sources (29.5%).

CONCLUSION

Distinct differences in T-cell integrin expression exists between patients in SIRS versus sepsis, as well as relative to the source of sepsis. Further work is needed to understand cause and effect relative to the progression from SIRS into sepsis.

Divergent invariant natural killer T-cell response to sepsis of abdominal vs. non-abdominal origin in human beings

BACKGROUND

The etiology of sepsis is broad. The peritoneal cavity displays compartmentalization with respect to inflammatory responses, so peripheral blood responses to sepsis of abdominal vs. non-abdominal origin are expected to be divergent. Lymphocytes and invariant natural killer T (iNKT) cells play important roles in survival from sepsis, as they dampen the neutrophil and macrophage responses. We assessed whether circulating iNKT cells display distinct phenotypic profiles depending on the presence of abdominal vs. non-abdominal infection with sepsis.

METHODS

Patients with sepsis, defined as infection confirmed microbiologically with a systemic inflammatory response syndrome (SIRS), were enrolled prospectively. They were categorized as having either exclusively sepsis of abdominal or exclusively non-abdominal origin. The white blood cell (WBC) count was recorded. Whole-blood staining with monoclonal antibodies to CD3, V-alpha-24 (to identify iNKT cells), and CD69 (marker of early activation) was applied.

RESULTS

Of the 53 enrolled patients, 18 had abdominal infection. Pneumonia was the most common non-abdominal type. There was no difference in gender, age, Acute Physiology and Chronic Health Evaluation (APACHE) II score, WBC count, or CD3(+) T cells (7.1%±1.6% vs. 6.5%±0.9%; p=0.75) in the two groups. Patients with abdominal infection had a higher proportion of iNKT cells (2.7%±1.1% vs. 0.89%±0.14%; p=0.032). Correcting for WBC count, this translated into a higher absolute number of iNKT cells (3.4±1.8×10(7)/L vs. 0.74±0.15×10(7)/L; p=0.03). Patients with sepsis of abdominal origin had a lower percentage of CD69(+) iNKT cells (9.1%±3.1% vs. 27.2%±5.8%; p=0.028). In patients in shock vs. those who were not, patients with non-abdominal infection exhibited a greater number of iNKT cells (1.47±0.3 v. 0.62±0.1×10(7)/L; p=0.022) and percentage of activated iNKT cells (53±14.5% vs. 17.9±4.8%; p=0.04). Patients with non-abdominal infection who died had a lower absolute number of activated iNKT cells (0.8±1.2×10(7)/L vs. 0.34±0.1×10(7)/L; p=0.023); however, no such shock or death correlation was noted in patients with sepsis of abdominal origin.

CONCLUSIONS

Divergent sepsis etiologies display distinct blood iNKT cell population changes. In non-abdominal infection, this difference was associated with septic shock and death. Elucidating the importance and basis for these changes relative to the response to sources of infection will help clarify appropriate diagnosis and management of the patient with sepsis.

Comparison of gastrotomy closure modalities for natural orifice transluminal surgery: a canine study

BACKGROUND

Reliable closure of the gastrotomy after transgastric natural orifice transluminal endoscopic surgery (NOTES) remains unresolved.

OBJECTIVE

To compare the technical aspects and clinical and histologic outcomes of NOTES gastrotomy closure techniques.

DESIGN

Experimental study.

SETTING

Animal laboratory.

PATIENTS

Thirty-four dogs, 14 for nonsurvival study and 20 for survival study.

INTERVENTIONS

The animals randomly received different gastrotomy closures after NOTES: endoclip, omentoplasty, over-the-scope-clip (OTSC), and hand-suturing.

MAIN OUTCOME MEASUREMENTS

Procedure time, closure strength, survival, postoperative adverse events, and histologic evaluation of wound healing.

RESULTS

Omentoplasty and OTSC groups needed shorter procedure times and fewer clips than the endoclip group. The endoclip and omentoplasty groups generated similar leakage pressures (34.5 ± 2.6 vs 42.2 ± 4.1 mm Hg, P > .05), both lower than OTSC and hand-suturing groups (81.5 ± 2.1 and 87.0 ± 3.0 mm Hg, respectively, P < .001). Of the 20 animals in the survival study (all 4 groups), only 2 of 6 in the endoclip group were killed prematurely due to sepsis. Necropsy revealed the OTSC group reached a 100% clip retention rate, higher than the endoclip (47.9%) and omentoplasty groups (44.4%, P < .05) rates. Complete healing, defined as intact and continuous gastric layers microscopically, was seen in 83.3% of animals (5 of 6) in the omentoplasty group, comparable with OTSC (4 of 6, 66.7%, P = .500) but higher than the endoclip group (1 of 6, 16.7%, P = .04).

LIMITATIONS

Animal study.

CONCLUSIONS

Omentoplasty is easier and safer for NOTES gastrotomy closure than endoclips and offers safety profile and efficacy similar to OTSC and hand-suturing.

Intraperitoneal wound in abdominal surgery

The intraperitoneal wound is often forgotten after transperitoneal surgery. This review is a on the peritoneum and the implications of peritoneal injury after surgery. This review will focus on the intraperitoneal wound response after surgical injury.

Vascularized atrial tissue patch cardiomyoplasty with omentopexy improves cardiac performance after myocardial infarction

BACKGROUND

The tissue-engineered cardiac patch can alleviate ventricular remodeling and improve functional recovery in experimental myocardial infarction. However, the size of the engineered patch is limited due to insufficient vascularization. This study evaluated the effects of autologous atrial tissue patch cardiomyoplasty and omentopexy in rats with myocardial infarction.

METHODS

Myocardial infarction was induced by left coronary artery ligation in Sprague-Dawley rats. Three weeks later, either a patch of left atrium (A group) or omentum (O group) or both (OA group) were placed over the infarct zone. The atrial tissue patch was harvested from the autologous left atrial appendage along its long axis. The rats in the Control group received rethoracotomy only. After 4 weeks, the survival of the transplanted atrial tissue patch, ventricular remodeling, and cardiac performance were examined.

RESULTS

After 4 weeks, surviving myocardium was only detected in the OA group, as indicated by immunolabeling of cardiac troponin-I. Compared with the Control group, only animals in the OA group showed improved heart function assessed by left ventricular ejection fraction (57.9% ± 5.8% vs 47.5% ± 4.5%, p < 0.05) and left ventricular fractional shortening (25.2% ± 3.6% vs 20.7% ± 2.0%, p < 0.05). The histologic analysis demonstrated increased scar thickness in the OA group. This was accompanied by increased angiogenesis of the border zone but decreased expression and activity of matrix metalloproteinase and endothelin-1 levels.

CONCLUSIONS

The omentopexy supported the survival of the autologous atrial tissue patch, which resulted in attenuated ventricular remodeling and restoration of heart function in rats with myocardial infarction. Our findings might represent a novel therapeutic strategy for heart failure.

Diclofenac inhibits tumor growth in a murine model of pancreatic cancer by modulation of VEGF levels and arginase activity

Background

Diclofenac is one of the oldest anti-inflammatory drugs in use. In addition to its inhibition of cyclooxygenases (COX), diclofenac potently inhibits phospholipase A₂ (PLA₂), thus yielding a broad anti-inflammatory effect. Since inflammation is an important factor in the development of pancreatic tumors we explored the potential of diclofenac to inhibit tumor growth in mice inoculated with PANCO2 cells orthotopically.

Methodology/Principal Findings

We found that diclofenac treatment (30 mg/kg/bw for 11 days) of mice inoculated with PANC02 cells, reduced the tumor weight by 60%, correlating with increased apoptosis of tumor cells. Since this effect was not observed in vitro on cultured PANCO2 cells, we theorized that diclofenac beneficial treatment involved other mediators present in vivo. Indeed, diclofenac drastically decreased tumor vascularization by downregulating VEGF in the tumor and in abdominal cavity fluid. Furthermore, diclofenac directly inhibited vascular sprouting ex vivo. Surprisingly, in contrast to other COX-2 inhibitors, diclofenac increased arginase activity/arginase 1 protein content in tumor stroma cells, peritoneal macrophages and white blood cells by 2.4, 4.8 and 2 fold, respectively. We propose that the subsequent arginine depletion and decrease in NO levels, both in serum and peritoneal cavity, adds to tumor growth inhibition by malnourishment and poor vasculature development.

Conclusion/Significance

In conclusion, diclofenac shows pronounced antitumoral properties in pancreatic cancer model that can contribute to further treatment development. The ability of diclofenac to induce arginase activity in tumor stroma, peritoneal macrophages and white blood cells provides a tool to study a controversial issue of pro-and antitumoral effects of arginine depletion.

Peritoneal changes due to laparoscopic surgery

Background

Laparoscopic surgery has been incorporated into common surgical practice. The peritoneum is an organ with various biologic functions that may be affected in different ways by laparoscopic and open techniques. Clinically, these alterations may be important in issues such as peritoneal metastasis and adhesion formation.

Methods

A literature search using the Pubmed and Cochrane databases identified articles focusing on the key issues of laparoscopy, peritoneum, inflammation, morphology, immunology, and fibrinolysis.

Results

Laparoscopic surgery induces alterations in the peritoneal integrity and causes local acidosis, probably due to peritoneal hypoxia. The local immune system and inflammation are modulated by a pneumoperitoneum. Additionally, the peritoneal plasmin system is inhibited, leading to peritoneal hypofibrinolysis.

Conclusion

Similar to open surgery, laparoscopic surgery affects both the integrity and biology of the peritoneum. These observations may have implications for various clinical conditions.

Ascites regression and survival increase in mice bearing advanced-stage human ovarian carcinomas and repeatedly treated intraperitoneally with CpG-ODN

Tumor cell growth, even in advanced stages of ovarian cancer, is nearly always restricted to the peritoneal cavity; therefore, repeated intraperitoneal injections of oligodeoxynucleotides containing dinucleotides with unmethylated CpG motifs (CpG-ODN) recruiting and activating innate effector cells throughout the abdominal cavity to the tumor site might control tumor cell growth and ascites formation. After a single CpG-ODN treatment, in IGROV-1 ovarian tumor ascites-bearing athymic mice, the number of tumor cells declined rapidly and markedly, and ascites volumes declined shortly after treatment (5 h), increasing thereafter at a slower rate than in controls. When administered every 7 days for 4 weeks, CpG-ODN had only a marginal effect on survival time, whereas administration 5 days/wk for 3 or 4 weeks led to a significantly increased survival time as compared with controls (P<0.005) and completely controlled ascites growth without apparent toxicity, although a disorganization of lymphoid organs was observed. Bio-plex assay of cytokine levels in peritoneal fluid of ascites-bearing mice after CpG-ODN treatment revealed an increase in interleukin (IL)-6, IL-10, IL-12, and interferon-gamma at 24 hours, which returned to control mice levels at 48 to 96 hours, whereas the high levels of angiogenic factors remained unchanged. Depletion of natural killer or monocytes/macrophages only slightly influenced the CpG-ODN-induced reduction of ascites tumor cells, indicating that the antitumor activity might not be related to a specific cell/cytokine but rather to the repertoire of cells and cytokines accumulated in the peritoneal cavity. Thus, our data suggest a relevant role for repeated activation of cells and cytokines of innate immunity in the therapy of ovarian cancer patients with malignant ascites.

Omentoplasty for gastrotomy closure after natural orifice transluminal endoscopic surgery procedures (with video)

INTRODUCTION

The utility of the greater omentum has not been assessed in transluminal access closure after natural orifice transluminal endoscopic surgery (NOTES) procedures.

OBJECTIVE

Our purpose was to evaluate the feasibility, efficacy, and safety of omentoplasty for gastrotomy closure.

METHODS AND PROCEDURES

Survival experiments in 9 female 40-kg pigs were randomly assigned to 3 groups: group A, endoscopic full-thickness resection (EFTR) for transgastric access and peritoneoscopy without closure; group B, ETFR and peritoneoscopy with omentoplasty (flap of omentum is pulled into the stomach and attached to the gastric mucosa with clips but no clips are used for gastrotomy closure itself); group C, balloon dilation for opening and peritoneoscopy followed by omentoplasty for closure. The animals were observed for 2 weeks and then underwent endoscopy and necropsy with histologic evaluation.

RESULTS

Transgastric opening and peritoneoscopy were achieved in all pigs. In groups B and C, a flap of omentum was easily placed to seal the gastrotomy and then attached to the gastric mucosa with 2 to 5 clips (median 4) in 7 to 20 minutes (median 15 minutes). In group A, peritonitis developed in all animals. In both groups B and C, all animals survived 15 days with no peritonitis and minimal adhesions outside the gastrotomy site. In addition, all achieved complete healing (transmural, n = 4; mucosal ulceration, n = 2) of the gastrotomy site. One animal in group B had an 18-mm abscess in the omental flap.

LIMITATIONS

Animal model, small sample size, lack of appropriate controls for group C.

CONCLUSIONS

Omentoplasty of the gastrotomy site is a technically feasible method to seal balloon-created transgastric access to the peritoneal cavity after NOTES procedures.

Reducing peritoneal vascular endothelial growth factor concentration and inhibiting cancer scattering in a mouse model of laparoscopy

OBJECTIVE

The objective of the study was to investigate the efficacy of early intraperitoneal (i.p.) paclitaxel administration in reducing vascular endothelial growth factor (VEGF) concentration in peritoneal fluid and preventing intraoperative cancer scattering during laparoscopy.

STUDY DESIGN

Nude mice were given i.p. ovarian cancer SKOV-3 xenografts to simulate intraoperative cancer dissemination and were assigned into concurrent- (day 0) and salvage-giving (day 5) treatment groups and nontreatment and nonxenografted groups.

RESULTS

The xenografted nontreatment group showed markedly increased peritoneal VEGF concentrations, whereas the paclitaxel (no-tumor) control group showed significantly reduced concentrations. In mice with cancer xenografts, both concurrent- and salvage-giving treatment groups showed significantly decreased peritoneal VEGF concentrations (P < .05), and the concurrent-giving group had significantly fewer implanted cancer nodules (P < .05), whereas the salvage-giving group had decreased total tumor weights (P < .05) compared with nontreatment. Total tumor weights were found closely correlated to peritoneal VEGF concentrations in a positive exponential relationship (P = .003, R(2) = 0.581).

CONCLUSION

Early treatment with IP paclitaxel significantly decreased the VEGF concentration in peritoneal fluid, which was associated with reduced implantation and growth of disseminated cancer cells after laparoscopy. These encouraging results suggest a useful strategy for future clinical applications.

Neovascularization induced by porous collagen scaffold implanted on intact and cryoinjured rat hearts

The potential of collagen scaffolds for promoting angiogenesis/arteriogenesis was studied in vivo by implantation on healthy or cryoinjured left ventricles of rats up to 60 days post-injury. Blood vessels content and extra-vascular cell infiltration were evaluated within the collagen scaffold, the cryoinjured areas, and the "border zones" of the myocardium facing the cryoinjured zones. The collagen cardiac patches were almost completely absorbed in 60 days and became populated by new arterioles and capillaries in both intact and cryoinjured heart (arterioles in cryoinjured vs. intact zones were about 2,3-fold higher; capillaries in cryoinjured vs. intact zones were 1.7-fold higher). Collagen cardiac patches exerted a "trophic" effect on the organizing granulation tissue that emerged from the wound-healing process, increasing vessel density of 2.7-fold for arterioles and 4-fold for capillaries. Interstitial cells in collagen cardiac patches rarely (<1%) expressed cardiogenic stem cells markers such as Sca-1- or MDR1, whereas markers of neural crest cells GFAP(+)/nestin(+) cells ranged from 3/30% to 30/70% in collagen cardiac patches placed on intact vs. cryoinjured heart, respectively. Myofibroblasts and cardiomyocytes (CM) were absent but macrophages populated the collagen scaffolds even after 60 days from implantation. Western blotting of collagen cardiac patches after implantation on intact/cryoinjured hearts confirmed that markers of endothelial and smooth muscle cells, but not of CM, were expressed. The porous collagen scaffold was able to elicit a powerful angiogenetic and arteriogenetic response in the intact and cryoinjured hearts, representing an ideal tool for therapeutic angio-arteriogenesis and a potentially useful substrate for stem cell seeding.