Malignant mesothelioma: A clinicopathological study of 76 cases with emphasis on immunohistochemical evaluation along with review of the literature.

INTRODUCTION: Malignant mesothelioma is an aggressive neoplasm arising from serosal lining and has a poor prognosis. Definite diagnosis requires confirmation through a biopsy; however, it is sometimes difficult on microscopic evaluation alone and requires the use of a wide panel of immunohistochemical markers. So, immunohistochemistry (IHC) is of paramount importance and must be routinely used for a definite diagnosis. Till date, very few studies on morphology and detailed IHC markers of mesothelioma have been reported from India. AIMS: To analyze the histomorphological findings of malignant mesothelioma, study the utility and role of the various immunohistochemical markers. MATERIAL AND METHODS: A total of 76 cases of mesotheliomas diagnosed at a tertiary cancer center in Udaipur were analyzed retrospectively from January 2015 to January 2020. Comprehensive data were analyzed including demographic, clinical, radiological, histopathological features along with a wide panel of IHC markers. RESULTS: Mesothelioma occurs over a wide age range from 40 to 70 years. It most commonly involved pleura in 68 cases (89.47%) with very few cases from the peritoneum. On computed tomography (CT) scan, nodular pleural or peritoneal thickening was present. On microscopy, the most common histopathological type was epithelioid mesothelioma (58 cases, 74.3%) followed by sarcomatous (9 cases, 12.8%), deciduoid (6 cases, 8.6%), and 3 cases of biphasic (4.3%). On IHC, WT1, mesothelin, and calretinin markers were positive in 85.91%, 80%, and 93.33% cases of mesothelioma, respectively. Other markers were helpful to rule out differential diagnosis in difficult scenarios. CONCLUSION: Therefore, the correlation of histopathology with clinico-radiological findings and judicious use of a panel of IHC markers is required for routine evaluation and definite diagnosis. IHC is also useful in situations with similar morphological spectrum in specific locations.

The significance of post-radiotherapy parametrial involvement and the necessity of parametrial resection in locally-recurrent or persistent cervical cancer developed after radiotherapy.

OBJECTIVE: To retrospectively evaluated the prognostic significance of post-radiotherapy parametrial involvement (PMI), the necessity of parametrial resection, and the optimal salvage surgery in locally recurrent or persistent cervical cancer developed after radiotherapy. METHODS: Patients who developed recurrent or persistent cervical cancer in a previously irradiated field and were subsequently treated with salvage surgery were identified, and the prognostic impact of post-radiotherapy PMI on patient's survival was first investigated. Then, the optimal salvage surgery for patients with post-radiotherapy PMI as well as the predictors for post-radiotherapy PMI were evaluated. RESULTS: A total of 60 patients underwent salvage surgery for recurrent or persistent diseases. Of these, 21 (35.0%) showed post-radiotherapy PMI (PMI-group). Patients in PMI-group showed significantly shorter progression-free survival (PFS) than those in non-PMI-group (p = 0.01). In both PMI-group and non-PMI-group, PFS was affected by the completeness of salvage surgery. In non-PMI-group, less radical surgery achieved similar therapeutic efficacy to more radical surgery (3-year PFS rates: 62.5% versus 54.1%, p = 0.91). In contrast, in PMI-group, not less radical surgery but more radical surgery achieved curative therapeutic efficacy (3-year PFS rate: 0% versus 28.9%). Maximum tumor diameter, deep stromal invasion, and LVSI were found to be predictors of post-radiotherapy PMI. CONCLUSION: Post-radiotherapy PMI is an indicator of short survival after salvage surgery in patients with locally recurrent or persistent cervical cancer developed after radiotherapy. Both less radical and more radical surgery have curative therapeutic efficacies in patients without post-radiotherapy PMI, if the tumor could be resected with an adequate surgical margin. Thus, hysterectomy type should be tailored to the risk for post-radiotherapy PMI.

Sonographic features of endometriosis infiltrating the lateral parametrium.

OBJECTIVE: Lateral parametrium endometriosis (LPE) can be associated with infiltration of ureters and hypogastric plexus, causing severe painful symptoms and functional impairment, and requiring complex and extensive surgery. The aim of this study was to evaluate the presentation of LPE lesions at transvaginal ultrasound, identifying sonographic features for disease recognition and mapping. METHODS: This was a retrospective case-series of women with sonographic suspect of LPE confirmed at surgical exploration. We carried out a descriptive analysis of the ultrasound patterns of presentation and compared the features of the lesions according to their location cranially or caudally to the uterine artery. RESULTS: Our population included 23 women, with a total of 26 parametrial lesions: all of them were hypoechoic, with absence of vascularization. Lesions lying above the uterine artery presented more frequently as ill-defined nodules (78.6 %, p < 0.01) and were associated with ipsilateral reduced or absent ovarian mobility (92.9 %, p < 0.01); the ones located below the uterine artery appeared more frequently as fan-shaped lesions with retraction of the surrounding tissues (83.3 %). Ureteral involvement was observed at surgery in 43.5 % of cases. In all patients, deep infiltrating endometriosis of the posterior compartment was observed: the utero-sacral ligaments were the most common location affected concurrently. CONCLUSIONS: LPE may present at transvaginal sonography as hypoechoic, not vascularized lesions, most frequently with a nodular or with a fan-shaped appearance, respectively cranially or caudally to the uterine artery. Reduced ovarian sliding and ureteral involvement are commonly associated.

Peritoneal Hydatid Cysts in Children: A Case Series of Rare Echinococcosis Localization.

Peritoneal hydatid cysts are rare in children even in endemic areas. The primary or secondary origin of this site remains controversial, especially in children. Secondary peritoneal hydatid cysts are mainly the result of spontaneous or traumatic rupture of concomitant liver cysts or the leakage of cystic content during surgery. The purpose of our study is to present the largest case series of peritoneal hydatidosis in children. In addition, we aimed to assess the clinical and paraclinical findings as well as the management of echinococcosis at this location in children. The present case series is a study of ten children with peritoneal hydatid cysts, who underwent surgical intervention between 2013 and 2018 in the Pediatric Surgery Department, University of Monastir (Monastir, Tunisia). The mean age of the children was six years. All children presented abdominal pain, and underwent ultrasonography and contrast-enhanced computed tomography of the abdomen. Two patients had been operated on for lung hydatid cysts six months prior to the study. In two cases, radiologic investigations revealed the presence of an uncomplicated hepatic hydatid cyst located in segments II and IV. All patients underwent surgery, of which four underwent laparoscopy. Post-surgery, all patients received albendazole for three months, and the follow-up period was uneventful. Currently, all patients are in good health. Peritoneal hydatid disease is frequently secondary to the rupture of a primary hepatic cyst. Diagnosis is performed by abdominal ultrasound, computed tomography, and a positive serology result. Open or laparoscopic excision can be combined with medical treatment.

Collagen-rich omentum is a premetastatic niche for integrin α2-mediated peritoneal metastasis.

The extracellular matrix (ECM) plays critical roles in tumor progression and metastasis. However, the contribution of ECM proteins to early metastatic onset in the peritoneal cavity remains unexplored. Here, we suggest a new route of metastasis through the interaction of integrin alpha 2 (ITGA2) with collagens enriched in the tumor coinciding with poor outcome in patients with ovarian cancer. Using multiple gene-edited cell lines and patient-derived samples, we demonstrate that ITGA2 triggers cancer cell adhesion to collagen, promotes cell migration, anoikis resistance, mesothelial clearance, and peritoneal metastasis in vitro and in vivo. Mechanistically, phosphoproteomics identify an ITGA2-dependent phosphorylation of focal adhesion kinase and mitogen-activated protein kinase pathway leading to enhanced oncogenic properties. Consequently, specific inhibition of ITGA2-mediated cancer cell-collagen interaction or targeting focal adhesion signaling may present an opportunity for therapeutic intervention of metastatic spread in ovarian cancer.

Longitudinal Changes of NF-κB Downstream Mediators and Peritoneal Transport Characteristics in Incident Peritoneal Dialysis Patients.

The role of intra-peritoneal mediators in the regulation peritoneal transport is not completely understood. We investigate the relation between longitudinal changes in dialysis effluent level of nuclear factor kappa-B (NF-κB) downstream mediators and the change in peritoneal transport over 1 year. We studied 46 incident PD patients. Their peritoneal transport characteristics were determined after starting PD and then one year later. Concomitant dialysis effluent levels of interleukin-6 (IL-6), cyclo-oxygenase-2 (COX-2) and hepatocyte growth factor (HGF) are determined. There were significant correlations between baseline and one-year dialysis effluent IL-6 and COX-2 levels with the corresponding dialysate-to-plasma creatinine level at 4 hours (D/P4) and mass transfer area coefficient of creatinine (MTAC). After one year, patients who had peritonitis had higher dialysis effluent IL-6 (26.6 ± 17.4 vs 15.1 ± 12.3 pg/ml, p = 0.037) and COX-2 levels (4.97 ± 6.25 vs 1.60 ± 1.53 ng/ml, p = 0.007) than those without peritonitis, and the number of peritonitis episode significantly correlated with the IL-6 and COX-2 levels after one year. In contrast, dialysis effluent HGF level did not correlate with peritoneal transport. There was no difference in any mediator level between patients receiving conventional and low glucose degradation product solutions. Dialysis effluent IL-6 and COX-2 levels correlate with the concomitant D/P4 and MTAC of creatinine. IL-6 and COX-2 may contribute to the short-term regulation of peritoneal transport.

Advanced glycation end products are associated with immature angiogenesis and peritoneal dysfunction in patients on peritoneal dialysis.

BACKGROUND: Deposition of advanced glycation end products (AGEs) is frequently found in the peritoneum of patients on peritoneal dialysis (PD). Angiogenesis is also observed in the peritoneum. However, the clinical significance of AGEs and angiogenesis in the peritoneum is not fully understood. We evaluated the maturation of capillary vessels and investigated whether AGEs are associated with angiogenesis and peritoneal function in the peritoneal membrane. METHODS: Peritoneum obtained when PD catheters were removed from 61 patients with PD was analyzed. The peritoneum was immunohistochemically stained with anti-CD34 (for endothelial cells), anti-alpha smooth muscle actin (αSMA) (for pericytes), and anti-AGE antibodies. We defined CD34-positive and αSMA-negative vessels as immature capillary vessels in peritoneal membranes using serial sections. We evaluated the associations between vessel density, peritoneal function (dialysate-to-plasma ratio for creatinine (D/P creatinine)), and the degree of AGE deposition. RESULTS: AGE accumulation in the interstitium was positively associated with the duration of PD (p < 0.01). AGE accumulation in the interstitium and vascular wall was positively correlated with the use of acidic solution (p < 0.05) and the maximum value of D/P creatinine (p < 0.05). AGE accumulation in the vascular wall was significantly associated with immature capillary density (CD34+/αSMA-) in the peritoneum (p < 0.01). Vessel density was not significantly correlated with the last measurement of D/P creatinine (p = 0.126, r = 0.202), However, immature capillary density was positively correlated with the last measurement of D/P creatinine (p < 0.05, r = 0.278). CONCLUSIONS: AGE accumulation is significantly associated with immature angiogenesis and peritoneal dysfunction in patients undergoing PD.

NPPB prevents postoperative peritoneal adhesion formation by blocking volume-activated Cl- current.

5-Nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) is a non-specific chloride channel blocker. Peritoneal adhesion is an inevitable complication of abdominal surgery and remains an important clinical problem, leading to chronic pain, intestinal obstruction, and female infertility. The aim of this study is to observe the effects of NPPB on peritoneal adhesions and uncover the underlying mechanism. The formation of postoperative peritoneal adhesions was induced by mechanical injury to the peritoneum of rats. MTT assay and wound-healing assay were used to evaluate proliferation and migration of primary cultured adhesion fibroblasts (AFB) respectively. Whole-cell chloride currents were measured using a fully automated patch-clamp workstation. Cell volume changes were monitored by light microscopy and video imaging. Our results demonstrated that NPPB could significantly prevent the formation of peritoneal adhesion in rats and inhibit the proliferation of AFB in a concentration-dependent manner. NPPB also reduced the migration of AFB cells with an IC50 of 53.09 µM. A 47% hypotonic solution successfully activated the ICl,vol in AFB cells. The current could be blocked by extracellular treatment with NPPB. Moreover, 100 µM NPPB almost completely eliminated the capacity of regulatory volume decrease (RVD) in these cells. These data indicate that NPPB could prevent the formation of postoperative peritoneal adhesions. The possible mechanism may be through the inhibition of the proliferation and migration of AFB cells by modulating ICl,vol and cell volume. These results suggest a potential clinical use of NPPB for preventing the formation of peritoneal adhesions.

Arrangement of myofibroblastic and smooth muscle-like cells in superficial peritoneal endometriosis and a possible role of transforming growth factor beta 1 (TGFß1) in myofibroblastic metaplasia.

PURPOSE: Superficial peritoneal endometriotic (pEM) lesions are composed of endometrial glands and stroma, in addition to a third component-myofibroblasts and smooth muscles (SM)-like cells. The latter develops secondary to a metaplasia. In this study, we characterised the third component cells in pEM according to differentiation markers in different micro-compartments. Furthermore, a possible effect of TGFß1 on myofibroblastic metaplasia in endometriotic epithelial cells was studied. METHODS: Seventy-six premenopausal patients were included. Peritoneal biopsies were excised from EM patients (n = 23), unaffected peritoneum (peritoneum from EM patients but without EM components, n = 5/23) and non-EM patients (n = 10). All peritoneal biopsies were immunolabeled for ASMA, calponin, collagen I, desmin, TGFß receptor 1 (R1), R2 and R3 in addition to ultrastructure examination by transmission electron microscopy (TEM) (n = 1). TGFß1 level was measured in peritoneal fluid (PF) (EM, n = 19 and non-EM, n = 13) collected during laparoscopy. Furthermore, TGFß1 effect on myofibroblastic metaplasia was studied in vitro. RESULTS: At the centre of pEM lesions, calponin immunolabeling outweighs the collagen I while in the periphery the reverse occurs. SM-like cells expressing desmin predominate at the periphery, while ASMA immunolabeling was detectable in all micro-compartments. Both indicate an abundance of myofibroblasts at the centre of pEM lesions and SM-like cells in the periphery. Although activated TGFß1 in PF did not differ between EM and non-EM, it inhibited the cell proliferation of the endometriotic epithelial cells and induced an upregulation in ASMA and collagen IA2 expression as well. CONCLUSION: The abundance of the myofibroblasts and SM-like cells points to a myofibroblastic metaplasia in pEM. Both cells are differentially arranged in the different micro-compartments of pEM lesions, with increasing cell maturity towards the periphery of the lesion. Furthermore, TGFß1 may play a role in the myofibroblastic metaplasia of the endometriotic epithelial cells. These findings provide a better insight in the micro-milieu in EM lesions, where most of the disease dynamics occur.

Early Detection of Imminent Encapsulating Peritoneal Sclerosis: Free Water Transport, Selected Effluent Proteins, or Both?

BACKGROUND: No diagnostic tool or methodology is currently available for early detection of imminent encapsulating peritoneal sclerosis (EPS). The objective of this study was to investigate the predictive value of free water transport (FWT) and construct a panel of peritoneal effluent proteins for EPS alone or in combination with FWT. These parameters could be incorporated in the follow-up of peritoneal dialysis (PD) patients. METHODS: A case-control study, nested in a longitudinal PD patient cohort, was conducted. Time-specific areas under the receiver operating characteristic (ROC) curve were calculated for FWT and effluent biomarkers at a lag time up to 3 years before EPS diagnosis. Free water transport was combined with appearance rates (AR) of biomarkers to assess their clinical validity. RESULTS: Free water transport volume and AR of effluent biomarkers were investigated in 11 EPS patients and 34 long-term PD patients. Diagnostic performance was best for FWT (area under the curve [AUC] 0.94) followed by plasminogen activator inhibitor (PAI-1) AR. Throughout, diagnostic panels of FWT and AR of cancer antigen 125 (CA125), interleukin-6 (IL-6), or (PAI-1) yielded specificity estimates above 84%. The combination of FWT and PAI-1 AR identified the largest proportion of EPS patients at 1 year prior to diagnosis (sensitivity 100%, specificity 94%). CONCLUSION: Measurement of FWT is simple and has the highest predictive value for imminent EPS. The addition of effluent biomarkers provides an all-round insight into the state of the peritoneum. Our data indicate that combining FWT with either PAI-1, CA125, or IL-6 has the highest specificity. This is required to avoid unnecessary discontinuation of PD treatment.

Embryology, anatomy, physiology and pathophysiology of the peritoneum and the peritoneal vasculature.

The peritoneum is a large serous membrane with both epithelial and mesenchymal features, and is essential for maintaining an intra-abdominal homeostatic equilibrium. The peritoneum plays a central role in the pathogenesis of a number of disorders. Pathological processes affecting the peritoneum such as inflammation and carcinomatosis can have serious clinical consequences, but the pathophysiology of these conditions is poorly understood. Understanding peritoneal embryology, anatomy and physiology is crucial to comprehend pathophysiological mechanisms and to devise a new focus for research. The vascular response to pathological processes appears to be of considerable importance, since the peritoneal vasculature plays a pivotal role in most associated diseases. Therefore, this review summarizes currently available literature with special emphasis on the development, anatomy and function of the peritoneal vasculature. Pathological processes are described to illustrate physiological and pathophysiological characteristics of the peritoneum.

Peritoneal and Systemic Responses of Obese Type II Diabetic Rats to Chronic Exposure to a Hyperbranched Polyglycerol-Based Dialysis Solution.

Metabolic syndrome (MetS) is commonly observed among peritoneal dialysis (PD) patients, and hyperbranched polyglycerol (HPG) is a promising glucose-sparing osmotic agent for PD. However, the biocompatibility of a HPG-based PD solution (HPG) in subjects with MetS has not been investigated. This study compared the local and systemic effects of a HPG solution with conventional physioneal (PYS) and icodextrin (ICO) PD solutions in rats with MetS. Obese type 2 diabetic ZSF1 rats received a daily intraperitoneal injection of PD solutions (10 mL) for 3 months. The peritoneal membrane (PM) function was determined by ultrafiltration (UF), and the systemic responses were determined by profiling blood metabolic substances, cytokines and oxidative status. Tissue damage was assessed by histology. At the end of the 3-month treatment with PD solutions, PM damage and UF loss in both the PYS and ICO groups were greater than those in the HPG group. Blood analyses showed that compared to the baseline control, the rats in the HPG group exhibited a significant decrease only in serum albumin and IL-6 and a minor glomerular injury, whereas in both the PYS and ICO groups, there were more significant decreases in serum albumin, antioxidant activity, IL-6, KC/GRO (CXCL1) and TNF-α (in ICO only) as well as a more substantial glomerular injury compared to the HPG group. Furthermore, PYS increased serum creatinine, serum glucose and urine production. In conclusion, compared to PYS or ICO solutions, the HPG solution had less adverse effects locally on the PM and systemically on distant organs (e.g. kidneys) and the plasma oxidative status in rats with MetS.

Pneumoperitoneum induced ischemia-reperfusion injury of the peritoneum - Preconditioning may reduce the negative side-effects caused by carbon-dioxide pneumoperitoneum - Pilot study.

INTRODUCTION: Laparoscopy is more beneficial than the conventional open technique, however the pneumoperitoneum created may have an ischemic side effect. OBJECTIVE: Our aim was to evaluate the protective effects of preconditioning during laparoscopic cholecystectomies (LC). METHODS: 30 patients were randomized into 2 groups: I. PreC (preconditioning: 5 min. inflation, 5 min. deflation, followed by conventional LC), II: LC (conventional LC). Blood samples were taken before hospitalization (C = control), before surgery, after anaesthesia (B.S.), after surgery (A.S.) and 24 hours after the procedure (24 h). Measured parameters were: malondialdehyde (MDA), reduced glutathione (GSH), sulfhydril groups (-SH), superoxide-dismutase (SOD), catalase (CAT), myeloperoxidase (MPO), length of hospitalization and pain (VAS = visual analogue scale). RESULTS: Compared to the BS levels, no significant changes were detected in SOD's activity and MDA levels. GSH concentrations were significantly increased in the PreC group after operation. SH-, MPO, CAT and liver function enzymes were not significantly different. Hospitalization was shorter in the PreC group. Based on the VAS score patients had less pain in the PreC group. CONCLUSION: Significant differences concerning PreC group were found in GSH values. In the PreC group pain decreased by 2-2.5 units following the procedure, 24 h after surgery, and hospitalisation was also significantly shorter. In our pilot study the potential protective effect of preconditioning could be defined.

Combined laparoscopic resection of intestinal stenosis of Garré and open preperitoneal mesh repair for irreducible femoral hernia.

Intestinal stenosis of Garré is a rare condition caused by a benign fibrous bowel stricture due to complicated strangulated hernia. We present a case of intestinal stenosis of Garré associated with right femoral hernia in an 85-year-old woman. The patient visited our hospital with a 2-day history of vomiting. Her abdomen was slightly distended. A mass was palpated in the right groin region. CT showed prolapse of the small intestine in the right groin region. An incarcerated right femoral hernia was diagnosed and manually reduced. Thirteen days later, the patient complained of abdominal pain. CT revealed dilatation and caliber change in part of the small bowel, indicating a small bowel obstruction due to intestinal stenosis of Garré. Laparoscopic release of the bowel obstruction and femoral hernia repair via an anterior approach were performed simultaneously. No recurrence of femoral hernia or bowel obstruction was noted at the 15-month follow-up.

The longitudinal effects of peritonitis on peritoneal membrane function
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BACKGROUND: The longitudinal effects of peritoneal dialysis (PD) peritonitis on small solute clearance and ultrafiltration are controversial. MATERIALS AND METHODS: We identified 27 patients with PD peritonitis over a 4-year period at a tertiary hospital. Adequacy tests at an "early" (1 - 3 months), "intermediate" (6 ± 2 months), and a "late" (12 ± 2 months) time period after the episode were compared with a pre-peritonitis baseline. The effect of time on serum albumin, weekly creatinine clearance, Kt/V, and net fluid volume removal was assessed. RESULTS: At 12 months, 16/27 (59.3%) patients were no longer on PD. Ten were transferred to hemodialysis, predominantly due to peritonitis (60%). Five patients died, and 1 received a renal allograft. Total daily fluid volume removal significantly decreased over time with an aggregated mean reduction of 523 mL/day between the baseline and 12-month test (1,624 ± 139 mL vs. 1,101 ± 160 mL; p = 0.02). This was due to an equivalent loss of both ultrafiltration and residual urine output, although the separate decline in these individual parameters was not statistically significant. There was no significant change in Kt/V, creatinine clearance, or serum albumin indicating preserved solute transport in those patients with sustained technique survival post peritonitis. CONCLUSION: Peritonitis is a common cause for transfer to hemodialysis. Fluid volume removal is the most significantly affected parameter at 12 months post peritonitis, driven by the combination of both ultrafiltration reduction and loss of residual diuresis. Clinicians should be aware that peritonitis identifies patients at high risk for technique failure. These findings should prompt clinicians to closely surveil volume status and consider backup dialytic strategies as early as 12 months post peritonitis.
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The BAFF / APRIL axis plays an important role in virus-induced peritoneal responses in rainbow trout.

IgM+ B cells have been recently demonstrated to be key regulators of peritoneal inflammation in teleost, as a large number of them occupy the peritoneal cavity after 48 h of antigenic stimulation. Despite this, the number of studies addressing the mechanism through which this cell population expands and differentiates in response to stimuli has been scarcely addressed. Because the BAFF/APRIL axis is known to play a major role in B cell survival and differentiation in mammals, we hypothesized that it could be affected in the peritoneal cavity in response to an inflammatory stimulus. To verify this hypothesis, we studied how BAFF, APRIL and the fish-specific related cytokine BALM as well as their putative receptors are regulated in rainbow trout after intraperitoneal (i.p.) injection of viral hemorrhagic septicemia virus (VHSV). When the transcriptional analysis was performed in total cells from the peritoneum, we observed that VHSV provoked an up-regulation of both BAFF and BAFF receptor (BAFF-R) mRNA levels. However, when we examined how isolated peritoneal IgM+ B cells were transcriptionally affected by VHSV i.p. injection, we found that APRIL, BALM and the transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI) were also up-regulated in response to the virus. IgM- cells, on the other hand, only up-regulated BALM transcription in response to VHSV. Finally, to gain further insight on the role that these cytokines play in the peritoneum, we have studied their effect on the survival of peritoneal IgM+ B cells. This work demonstrates a key role for the BAFF/APRIL axis in the peritoneal inflammatory response and contributes to further understanding how IgM+ B cells are regulated at this specific peripheral site.

The effectiveness of heparin, platelet-rich plasma (PRP), and silver nanoparticles on prevention of postoperative peritoneal adhesion formation in rats

Purpose: To assess the effectiveness of heparin, platelet-rich plasma (PRP), and silver nanoparticles on prevention of postoperative adhesion in animal models. Methods: Sixty males Albino Wistar rats aged 5 to 6 weeks were classified into five groups receiving none, heparin, PRP, silver nanoparticles, PRP plus silver nanoparticles intraperitoneally. After 2 weeks, the animals underwent laparotomy and the damaged site was assessed for peritoneal adhesions severity. Results: The mean severity scores were 2.5 ± 0.9, 2.16 ± 0.7, 1.5 ± 0.5, 2.66 ± 0.88, and 2.25 ± 0.62 in the control, heparin, PRP, silver and PRP plus silver groups, respectively with significant intergroup difference (p = 0.004). The highest effective material for preventing adhesion formation was PRP followed by heparin and PRP plus silver. Moreover, compared to the controls, only use of PRP was significantly effective, in terms of adhesion severity (p = 0.01) . Conclusion: Platelet-rich plasma alone may have the highest efficacy for preventing postoperative peritoneal adhesions in comparison with heparin, silver nanoparticles and PRP plus silver nanoparticles.

The histophysiology and pathophysiology of the peritoneum.

The peritoneum is an extensive serous organ with both epithelial and mesenchymal features and a variety of functions. Diseases such as inflammatory peritonitis and peritoneal carcinomatosis can induce disturbance of the complex physiological functions. To understand the peritoneal response in disease, normal embryonic development, anatomy in healthy conditions and physiology of the peritoneum have to be understood. This review aims to summarize and discuss the literature on these basic peritoneal characteristics. The peritoneum is a dynamic organ capable of adapting its structure and functions to various physiological and pathological conditions. It is a key element in regulation of inflammatory responses, exchange of peritoneal fluid and prevention of fibrosis in the abdominal cavity. Disturbance of these mechanisms may lead to serious conditions such as the production of large amounts of ascites, the generation of fibrotic adhesions, inflammatory peritonitis and peritoneal carcinomatosis. The difficulty to treat diseases, such as inflammatory peritonitis and peritoneal carcinomatosis, stresses the necessity for new therapeutic strategies. This review provides a detailed background on the peritoneal anatomy, microenvironment and immunologic responses which is essential to generate new hypotheses for future research.