Effect of cellular senescence on the response of human peritoneal mesothelial cells to TGF-ß.

Transforming growth factor ß (TGF-ß) is implicated in both mesothelial-to-mesenchymal transition (MMT) and cellular senescence of human peritoneal mesothelial cells (HPMCs). We previously showed that senescent HPMCs could spontaneously acquire some phenotypic features of MMT, which in young HPMCs were induced by TGF-ß. Here, we used electron microscopy, as well as global gene and protein profiling to assess in detail how exposure to TGF-ß impacts on young and senescent HPMCs in vitro. We found that TGF-ß induced structural changes consistent with MMT in young, but not in senescent HPMCs. Of all genes and proteins identified reliably in HPMCs across all treatments and states, 4,656 targets represented overlapping genes and proteins. Following exposure to TGF-ß, 137 proteins and 46 transcripts were significantly changed in young cells, compared to 225 proteins and only 2 transcripts in senescent cells. Identified differences between young and senescent HPMCs were related predominantly to wound healing, integrin-mediated signalling, production of proteases and extracellular matrix components, and cytoskeleton structure. Thus, the response of senescent HPMCs to TGF-ß differs or is less pronounced compared to young cells. As a result, the character and magnitude of the postulated contribution of HPMCs to TGF-ß-induced peritoneal remodelling may change with cell senescence.

Caffeic acid phenethyl ester restores mitochondrial homeostasis against peritoneal fibrosis induced by peritoneal dialysis through the AMPK/SIRT1 pathway.

Increasing evidence suggests that peritoneal fibrosis induced by peritoneal dialysis (PD) is linked to oxidative stress. However, there are currently no effective interventions for peritoneal fibrosis. In the present study, we explored whether adding caffeic acid phenethyl ester (CAPE) to peritoneal dialysis fluid (PDF) improved peritoneal fibrosis caused by PD and explored the molecular mechanism. We established a peritoneal fibrosis model in Sprague-Dawley rats through intraperitoneal injection of PDF and lipopolysaccharide (LPS). Rats in the PD group showed increased peritoneal thickness, submesothelial collagen deposition, and the expression of TGFß1 and α-SMA. Adding CAPE to PDF significantly inhibited PD-induced submesothelial thickening, reduced TGFß1 and α-SMA expression, alleviated peritoneal fibrosis, and improved the peritoneal ultrafiltration function. In vitro, peritoneal mesothelial cells (PMCs) treated with PDF showed inhibition of the AMPK/SIRT1 pathway, mitochondrial membrane potential depolarization, overproduction of mitochondrial reactive oxygen species (ROS), decreased ATP synthesis, and induction of mesothelial-mesenchymal transition (MMT). CAPE activated the AMPK/SIRT1 pathway, thereby inhibiting mitochondrial membrane potential depolarization, reducing mitochondrial ROS generation, and maintaining ATP synthesis. However, the beneficial effects of CAPE were counteracted by an AMPK inhibitor and siSIRT1. Our results suggest that CAPE maintains mitochondrial homeostasis by upregulating the AMPK/SIRT1 pathway, which alleviates oxidative stress and MMT, thereby mitigating the damage to the peritoneal structure and function caused by PD. These findings suggest that adding CAPE to PDF may prevent and treat peritoneal fibrosis.

Faster both in operative time and functional recovery by the extraperitoneal daVinci SP-based robot-assisted radical prostatectomy: a propensity score matching analysis compared to transperitoneal multiport counterpart.

We aim to investigate the peri-operative outcomes after extraperitoneal single-port based robot-assisted radical prostatectomy (eSP-RARP) utilizing the da Vinci SP system compared to conventional transperitoneal multi-port counterparts (tMP-RARP), in an era when pelvic lymph node dissection (PNLD) was omitted for the node-negative case. With exclusion criteria of volume + 50 g, suspicious rectal invasion, and node-positive disease given relatively weak grasping power and limited range of motion from the current SP system, 50 consecutive patients (Since December 2021) with localized prostate cancer underwent eSP-RARP by a single urologist maintaining identical surgical technique for 100 consecutive tMP-RARP cases (Since December 2020). Given initial selection criteria, each group was matched to a 1:1 ratio based on the risk-stratification parameters and the prostate volume. The operative time, which was maintained in each group during the study period, was significantly faster in eSP-RARP groups than in tMP-RARP (149.2 vs. 163.2 min, p = 0.025), while the weight of the removed specimen (27.1 vs. 29.0 g, p = 0.420) and margin positivity (14.7% vs. 11.7% in pT2, p = 0.812) were similar. The gas-out (1.5 vs. 1.88 days, p = 0.003) and solid diet dates (2.26 vs. 3.22 days, p < 0.001) were faster in the eSP-RARP group. The single-pad continence dates (30.5 vs. 51.9 days, p = 0.145) and zero-pad continence dates (105.5 vs. 146.2 days, p = 0.210) were identical. 90-day single-pad continence rate was 92% vs. 82% (p = 0.142, 52% vs. 56% in zero-pad continence). Based on these, daVinci SP-based RARP restored bowel function faster with shorter operative time through an extraperitoneal approach than the conventional transperitoneal multi-port counterpart while maintaining similar incontinence outcomes in cases without a routine PNLD.

Comparison of the effect of Everolimus, Prednisolone, and a combination of both on experimentally induced peritoneal adhesions in rats.

Postoperative intra-abdominal adhesions represent a significant post-surgical problem. Its complications can cause a considerable clinical and cost burden. Herein, our study aimed to investigate the effect of Everolimus on peritoneal adhesion formation after inducing adhesions in rats. In this experimental study, adhesion bands were induced by intraperitoneal injection of 3 ml of 10% sterile talc solution in 64 male albino rats. The first group served as the control group. The second one received oral Prednisolone (1 mg/kg/day), the third received Everolimus (0.1 mg/kg/day), and group four received both drugs with similar dosages for four consecutive weeks. The formation of adhesion bands was qualitatively graded according to the Nair classification. The rats in the control group had extensive adhesions between the abdominal wall and the organs. Regarding substantial adhesion formation, 50% (8/16) of animals in the control group had substantial adhesions, while this rate in the groups receiving Prednisolone, Everolimus, and combination treatment was 31%, 31%, and 31%, respectively. Also, 68.75% (5/11) of the Prednisolone recipients had insubstantial adhesions, the same as Everolimus recipients, while in the combination group, 66.66% (10/15) rats had insubstantial adhesions. Everolimus demonstrated satisfactory results in reducing the rates of induced peritoneal adhesion in an experimental model, similar to Prednisolone and superior to a combination regime.

Sterile inflammation of peritoneal membrane caused by peritoneal dialysis: focus on the communication between immune cells and peritoneal stroma.

Peritoneal dialysis is a widely used method for treating kidney failure. However, over time, the peritoneal structure and function can deteriorate, leading to the failure of this therapy. This deterioration is primarily caused by infectious and sterile inflammation. Sterile inflammation, which is inflammation without infection, is particularly concerning as it can be subtle and often goes unnoticed. The onset of sterile inflammation involves various pathological processes. Peritoneal cells detect signals that promote inflammation and release substances that attract immune cells from the bloodstream. These immune cells contribute to the initiation and escalation of the inflammatory response. The existing literature extensively covers the involvement of different cell types in the sterile inflammation, including mesothelial cells, fibroblasts, endothelial cells, and adipocytes, as well as immune cells such as macrophages, lymphocytes, and mast cells. These cells work together to promote the occurrence and progression of sterile inflammation, although the exact mechanisms are not fully understood. This review aims to provide a comprehensive overview of the signals from both stromal cells and components of immune system, as well as the reciprocal interactions between cellular components, during the initiation of sterile inflammation. By understanding the cellular and molecular mechanisms underlying sterile inflammation, we may potentially develop therapeutic interventions to counteract peritoneal membrane damage and restore normal function.

Inhibition of STAT3 by S3I-201 suppress peritoneal fibroblast phenotype conversion and alleviate peritoneal fibrosis.

Peritoneal fibrosis is a common pathological response to long-term peritoneal dialysis (PD) and a major cause for PD discontinuation. Understanding the cellular and molecular mechanisms underlying the induction and progression of peritoneal fibrosis is of great interest. In our study, in vitro study revealed that signal transducer and activator of transcription 3 (STAT3) is a key factor in fibroblast activation and extracellular matrix (ECM) synthesis. Furthermore, STAT3 induced by IL-6 trans-signalling pathway mediate the fibroblasts of the peritoneal stroma contributed to peritoneal fibrosis. Inhibition of STAT3 exerts an antifibrotic effect by attenuating fibroblast activation and ECM production with an in vitro co-culture model. Moreover, STAT3 plays an important role in the peritoneal fibrosis in an animal model of peritoneal fibrosis developed in mice. Blocking STAT3 can reduce the peritoneal morphological changes induced by chlorhexidine gluconate. In conclusion, our findings suggested STAT3 signalling played an important role in peritoneal fibrosis. Therefore, blocking STAT3 might become a potential treatment strategy in peritoneal fibrosis.

Glued suture-less peritoneum closure in laparoscopic inguinal hernia repair reduces acute postoperative pain.

Inguinal hernia repair is performed more than 20 million times per annum, representing a significant health and economic burden. Over the last three decades, significant technical advances have started to reduce the invasiveness of these surgeries, which translated to better recovery and reduced costs. Here we bring forward an innovative surgical technique using a biodegradable cyanoacrylate glue instead of a traumatic suture to close the peritoneum, which is a highly innervated tissue layer, at the end of endoscopy hernia surgery. To test how this affects the invasiveness of hernia surgery, we conducted a cohort study. A total of 183 patients that underwent minimally invasive hernia repair, and the peritoneum was closed with either a conventional traumatic suture (n = 126, 68.9%) or our innovative approach using glue (n = 57, 31.1%). The proportion of patients experiencing acute pain after surgery was significantly reduced (36.8 vs. 54.0%, p = 0.032) by using glue instead of a suture. In accordance, the mean pain level was higher in the suture group (VAS = 1.5 vs. 1.3, p = 0.029) and more patients were still using painkillers (77.9 vs. 52.4%, p = 0.023). Furthermore, the rate of complications was not increased in the glue group. Using multivariate regressions, we identified that using a traumatic suture was an independent predictor of acute postoperative pain (OR 2.0, 95% CI 1.1-3.9, p = 0.042). In conclusion, suture-less glue closure of the peritoneum is innovative, safe, less painful, and possibly leads to enhanced recovery and decreased health costs.

Exploring the Role of Cell-Free Nucleic Acids and Peritoneal Dialysis: A Narrative Review.

INTRODUCTION: Cell-free nucleic acids (cf-NAs) represent a promising biomarker of various pathological and physiological conditions. Since its discovery in 1948, cf-NAs gained prognostic value in oncology, immunology, and other relevant fields. In peritoneal dialysis (PD), blood purification is performed by exposing the peritoneal membrane. Relevant sections: Complications of PD such as acute peritonitis and peritoneal membrane aging are often critical in PD patient management. In this review, we focused on bacterial DNA, cell-free DNA, mitochondrial DNA (mtDNA), microRNA (miRNA), and their potential uses as biomarkers for monitoring PD and its complications. For instance, the isolation of bacterial DNA in early acute peritonitis allows bacterial identification and subsequent therapy implementation. Cell-free DNA in peritoneal dialysis effluent (PDE) represents a marker of stress of the peritoneal membrane in both acute and chronic PD complications. Moreover, miRNA are promising hallmarks of peritoneal membrane remodeling and aging, even before its manifestation. In this scenario, with multiple cytokines involved, mtDNA could be considered equally meaningful to determine tissue inflammation. CONCLUSIONS: This review explores the relevance of cf-NAs in PD, demonstrating its promising role for both diagnosis and treatment. Further studies are necessary to implement the use of cf-NAs in PD clinical practice.

LncRNA RPL29P2 promotes peritoneal fibrosis and impairs peritoneal transport function via miR-1184 in peritoneal dialysis.

Peritoneal dialysis (PD), hemodialysis and kidney transplantation are the three therapies to treat uremia. However, PD is discontinued for peritoneal membrane fibrosis (PMF) and loss of peritoneal transport function (PTF) due to damage from high concentrations of glucose in PD fluids (PDFs). The mechanism behind PMF is unclear, and there are no available biomarkers for the evaluation of PMF and PTF. Using microarray screening, we found that a new long noncoding RNA (lncRNA), RPL29P2, was upregulated in the PM (peritoneal membrane) of long-term PD patients, and its expression level was correlated with PMF severity and the PTF loss. In vitro and rat model assays suggested that lncRNA RPL29P2 targets miR-1184 and induces the expression of collagen type I alpha 1 chain (COL1A1). Silencing RPL29P2 in the PD rat model might suppress the HG-induced phenotypic transition of Human peritoneal mesothelial cells (HPMCs), alleviate HG-induced fibrosis and prevent the loss of PTF. Overall, our findings revealed that lncRNA RPL29P2, which targets miR-1184 and collagen, may represent a useful marker and therapeutic target of PMF in PD patients.

The Impact of Positive Peritoneal Cytology on the Survival Rates of Early-Stage-Disease Endometrial Cancer Patients: Systematic Review and Meta-Analysis.

Background and Objectives: The impact of positive peritoneal cytology has been a matter of controversy in early-stage endometrial cancer for several years. The latest staging systems do not take into consideration its presence; however, emerging evidence about its potential harmful effect on patient survival outcomes suggests otherwise. In the present systematic review and meta-analysis, we sought to accumulate current evidence. Materials and Methods: Medline, Scopus, the Cochrane Central Register of Controlled Trials CENTRAL, Google Scholar and Clinicaltrials.gov databases were searched for relevant articles. Effect sizes were calculated in Rstudio using the meta function. A sensitivity analysis was carried out to evaluate the possibility of small-study effects and p-hacking. Trial sequential analysis was used to evaluate the adequacy of the sample size. The methodological quality of the included studies was assessed using the Newcastle-Ottawa scale. Results: Fifteen articles were finally included in the present systematic review that involved 19,255 women with early-stage endometrial cancer. The Newcastle-Ottawa scale indicated that the majority of included studies had a moderate risk of bias in their selection of participants, a moderate risk of bias in terms of the comparability of groups (positive peritoneal cytology vs. negative peritoneal cytology) and a low risk of bias concerning the assessment of the outcome. The results of the meta-analysis indicated that women with early-stage endometrial cancer and positive peritoneal cytology had significantly lower 5-year recurrence-free survival (RFS) (hazards ratio (HR) 0.26, 95% CI 0.09, 0.71). As a result of the decreased recurrence-free survival, patients with positive peritoneal cytology also exhibited reduced 5-year overall survival outcomes (HR 0.50, 95% CI 0.27, 0.92). The overall survival of the included patients was considerably higher among those that did not have positive peritoneal cytology (HR 12.76, 95% CI 2.78, 58.51). Conclusions: Positive peritoneal cytology seems to be a negative prognostic indicator of survival outcomes of patients with endometrial cancer. Considering the absence of data related to the molecular profile of patients, further research is needed to evaluate if this factor should be reinstituted in future staging systems.

Autophagy caused by oxidative stress promotes TGF-ß1-induced epithelial-to-mesenchymal transition in human peritoneal mesothelial cells.

Epithelial-to-mesenchymal transition (EMT) is one of the main causes of peritoneal fibrosis. However, the pathophysiological mechanisms of EMT, specifically its relationship with autophagy, are still unknown. This study aimed to evaluate the role of autophagy in transforming growth factor-beta 1 (TGF-ß1)-induced EMT in human peritoneal mesothelial cells (HPMCs). Primary cultured HPMCs were treated with TGF-ß1 (2 and 5 ng/mL) and changes in autophagy markers and the relationship between autophagy and EMT were evaluated. We also identified changes in EMT- and autophagy-related signaling pathways after autophagy and NADPH oxidase 4 (NOX4) inhibition. TGF-ß1 increased the generation of NOX4 and reactive oxygen species (ROS) in HPMCs, resulting in mitochondrial damage. Treatment with GKT137831 (20 µM), a NOX1/4 inhibitor, reduced ROS in the mitochondria of HPMC cells and reduced TGF-ß1-induced mitochondrial damage. Additionally, the indirect inhibition of autophagy by GKT137831 (20 µM) downregulated TGF-ß1-induced EMT, whereas direct inhibition of autophagy using 3-methyladenine (3-MA) (2 mM) or autophagy-related gene 5 (ATG5) gene silencing decreased the TGF-ß1-induced EMT in HPMCs. The suppressor of mothers against decapentaplegic 2/3 (Smad2/3), autophagy-related phosphoinositide 3-kinase (PI3K) class III, and protein kinase B (Akt) pathways, and mitogen-activated protein kinase (MAPK) signaling pathways, such as extracellular signal-regulated kinase (ERK) and P38, were involved in TGF-ß1-induced EMT. Autophagy and NOX4 inhibition suppressed the activation of these signaling pathways. Direct inhibition of autophagy and its indirect inhibition through the reduction of mitochondrial damage by upstream NOX4 inhibition reduced EMT in HPMCs. These results suggest that autophagy could serve as a therapeutic target for the prevention of peritoneal fibrosis in patients undergoing peritoneal dialysis.

The role of cytoreductive surgery and HIPEC for the treatment of primary and secondary peritoneal malignancies-experience from a tertiary care center in Germany.

PURPOSE: Peritoneal surface malignancies (PSM) are commonly known to have a dismal prognosis. Over the past decades, novel techniques such as cytoreductive surgery (CRS), hyperthermic intraperitoneal chemotherapy (HIPEC), and pressurized intraperitoneal aerosol chemotherapy (PIPAC) have been introduced for the treatment of PSM which could improve the overall survival and quality of life of patients with PSM. The decision to proceed with CRS and HIPEC is often challenging due the complexity of the disease, the extent of the procedure, associated side effects, and potential risks. Here, we present our experience with CRS and HIPEC to add to the ongoing discussion about eligibility criteria, technical approach, and expected outcomes and contribute to the evolution of this powerful and promising tool in the multidisciplinary treatment of patients with primary and secondary PSM. METHODS: A single-center retrospective chart review was conducted and included a total of 40 patients treated with CRS and HIPEC from April 2020 to September 2022 at the University Hospital Münster Department of Surgery. All patients had histologically confirmed primary or secondary peritoneal malignancies of various primary origins. RESULTS: Our study included 22 patients with peritoneal metastases from gastric cancer (55%), 8 with pseudomyxoma peritonei (20%), 4 with mesothelioma of the peritoneum (10%), and 6 patients with PSM originating from other primary tumor locations. Median PCI at time of cytoreduction was 4 (0-25). Completeness of cytoreduction score was 0 in 37 patients (92.5%), 1 in two patients (5%), and 2 in one patient (2.5%). Median overall survival across all patients was 3.69 years. CONCLUSION: Complete cytoreduction during CRS and HIPEC can be achieved for patients with low PCI, for patients with high PCI in low-grade malignancies, and even for patients with initially high PCI in high-grade malignancies following a significant reduction of cancer burden due to extensive preoperative treatment with PIPAC and systemic chemotherapy.

Differential expression and clinical significance of IGF2BP3 in peritoneal dialysate of patients with varying duration of peritoneal dialysis.

This study aims to investigate the differential expression of insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) in the peritoneal dialysate among patients with different durations of peritoneal dialysis and its association with the angiogenic marker vascular* endothelial growth factor (VEGF), the fibronectin (FN), and various clinical indicators. A cohort of 122 peritoneal dialysis patients was categorized into short-term (≤1 year, n = 33), mid-term (>1 and ≤5 years, n = 55), and long-term (>5 years, n = 34) groups based on dialysis duration. We utilized enzyme-linked immunosorbent assay (ELISA) and western blot assays to quantify the levels of IGF2BP3, VEGF, and FN in the dialysate. Our findings showed a progressive increase in IGF2BP3 levels with the duration of PD, with the long-term group exhibiting significantly higher levels than both the short-term and mid-term groups (p < 0.001). A positive correlation between IGF2BP3 and VEGF (r = 0.386, p = 0.013), as well as between IGF2BP3 and FN (r = 0.340, p = 0.030), was observed. IGF2BP3 levels also correlated positively with serum creatinine, calcium, and phosphorus levels. In vitro analysis further confirmed that IGF2BP3 expression is enhanced in human peritoneal mesothelial cells under high-glucose conditions (p < 0.05). The study highlights the potential of IGF2BP3 in PD effluent as a biomarker for monitoring PF progression, with its expression significantly correlated with the duration of PD (Pearson r = 0.897, p < 0.001). In conclusion, our results underscore a correlation between elevated IGF2BP3 levels and PD duration, suggesting the clinical significance of IGF2BP3 as a biomarker for PF progression.

Neoadjuvant chemotherapy does not improve survival for patients with high volume colorectal peritoneal metastases undergoing cytoreductive surgery.

BACKGROUND: Colorectal peritoneal metastases (CRPM) affects 15% of patients at initial colorectal cancer diagnosis. Neoadjuvant chemotherapy (NAC) prior to cytoreductive surgery (CRS) has been demonstrated to be a safe and feasible option, however there is limited data describing its efficacy in advanced peritoneal disease. This study evaluated the effect of NAC on survival in patients with high volume CRPM undergoing CRS with or without HIPEC. METHODS: A retrospective review of all patients who underwent CRS with or without HIPEC for CRPM from 2004 to 2019 at our institution was performed. The cohort was divided based on peritoneal carcinomatosis index (PCI) at surgery: Low Volume (PCI ≤ 16) and High Volume (PCI > 16). RESULTS: A total of 326 patients underwent CRS with HIPEC for CRPM. There were 39 patients (12%) with High Volume disease, and 15 of these (38%) received NAC. Patients with High Volume disease had significantly longer operating time, lower likelihood of complete macroscopic cytoreduction (CC-0 score), longer intensive care unit length of stay and longer hospital stay compared to Low Volume disease. In High Volume disease, the NAC group had a significantly shorter median survival of 14.4 months compared to 23.8 months in the non-NAC group (p = 0.046). CONCLUSION: Patients with High Volume CRPM achieved good median survival following CRS with HIPEC, which challenges the current PCI threshold for offering CRS. The use of NAC in this cohort did not increase perioperative morbidity but was associated with significantly shorter median survival compared to upfront surgery.

Peritoneal B1 and B2 cells respond differently to LPS and IL-21 stimulation.

Peritoneal B cells can be divided into B1 cells (CD11b+CD19+) and B2 cells (CD11b-CD19+) based on CD11b expression. B1 cells play a crucial role in the innate immune response by producing natural antibodies and cytokines. B2 cells share similar traits with B1 cells, influenced by the peritoneal environment. However, the response of both B1 and B2 cells to the same stimuli in the peritoneum remains uncertain. We isolated peritoneal B1 and B2 cells from mice and assessed differences in Interleukin-10(IL-10) secretion, apoptosis, and surface molecule expression following exposure to LPS and Interleukin-21(IL-21). Our findings indicate that B1 cells are potent IL-10 producers, possessing surface molecules with an IgMhiCD43+CD21low profile, and exhibit a propensity for apoptosis in vitro. Conversely, B2 cells exhibit lower IL-10 production and surface markers characterized as IgMlowCD43-CD21hi, indicative of some resistance to apoptosis. LPS stimulates MAPK phosphorylation in B1 and B2 cells, causing IL-10 production. Furthermore, LPS inhibits peritoneal B2 cell apoptosis by enhancing Bcl-xL expression. Conversely, IL-21 has no impact on IL-10 production in these cells. Nevertheless, impeding STAT3 phosphorylation permits IL-21 to increase IL-10 production in peritoneal B cells. Moreover, IL-21 significantly raises apoptosis levels in these cells, a process independent of STAT3 phosphorylation and possibly linked to reduced Bcl-xL expression. This study elucidates the distinct functional and response profiles of B1 and B2 cells in the peritoneum to stimuli like LPS and IL-21, highlighting their differential roles in immunological responses and B cell diversity.

Correlation Between the 8-hydroxy-2'-deoxyguanosine Level in the Peritoneal Solution of Patients Undergoing Peritoneal Dialysis and the Peritoneal Equilibration Test, Kt/V, Ferritin, and Albumin Levels.

INTRODUCTION: Peritoneal dialysis (PD) is an effective treatment  modality for advanced kidney failure, offering patients a significant  degree of independence. However, the long-term use of PD is  limited due to the degeneration of the peritoneal membrane,  resulting in reduced dialysis adequacy. Evaluating the peritoneal  membrane condition in patients with advanced kidney failure  who are undergoing PD is challenging with existing methods.  Therefore, this study aimed to investigate the correlation between  8-hydroxy-2'-deoxyguanosine (8OHDG) levels in the peritoneal  solution of patients undergoing PD and various factors, such  as peritoneal equilibration test (PET), dialysis adequacy (Kt/V),  underlying diseases, serum ferritin, and albumin levels. 8OHDG  is a sensitive marker of oxidative stress caused by DNA damage. METHODS: A total of 56 patients were included in this cross-sectional  study. Five milliliters of PD fluid were collected from the patients,  and 8-OHdG levels were measured using ELISA method. Then, they  were compared with PET, Kt/V, albumin, and ferritin markers in  the patients' files, and the results were analyzed by statistical tests. RESULTS: The study examined the correlation between 8OHDG  and other markers. It was found that this index had significant  associations with PET and underlying HTN (P < .05), whereas no  significant associations were identified with the other markers. CONCLUSION: The results of the present study demonstrate that  the level of 8OHDG, as one of the oxidative stress markers, could  be used to evaluate the function of the peritoneum in patients  undergoing PD. DOI: 10.52547/ijkd.7654.

Comparison of the perioperative outcomes of robot-assisted laparoscopic transperitoneal versus retraperitoneal partial nephrectomy for posterior-lateral renal tumors: a systematic review and meta-analysis.

The study aims to assess the available literature and compare the perioperative outcomes of robotic-assisted partial nephrectomy (RAPN) for posterior-lateral renal tumors using transperitoneal (TP) and retroperitoneal (RP) approaches. Systematically searched the Embase, PubMed, and Cochrane Library databases for literature. Eligible studies were those that compared TP-RAPN and RP-RAPN for posterior-lateral renal tumors. The data from the included studies were analyzed and summarized using Review Manager 5.3, which involved comparing baseline patient and tumor characteristics, intraoperative and postoperative outcomes, and oncological outcomes. The analysis included five studies meeting the inclusion criteria, with a total of 1440 patients (814 undergoing RP-RAPN and 626 undergoing TP-RAPN). Both groups showed no significant differences in age, gender, BMI, R.E.N.A.L. score, and tumor size. Notably, compared to TP-RAPN, the RP-RAPN group demonstrated shorter operative time (OT) (MD: 17.25, P = 0.01), length of hospital stay (LOS) (MD: 0.37, P < 0.01), and lower estimated blood loss (EBL) (MD: 15.29, P < 0.01). However, no significant differences were found between the two groups in terms of warm ischemia time (WIT) (MD: -0.34, P = 0.69), overall complications (RR: 1.25, P = 0.09), major complications (the Clavien-Dindo classification ≥ 3) (RR: 0.97, P = 0.93), and positive surgical margin (PSM) (RR: 1.06, P = 0.87). The systematic review and meta-analysis suggests RP-RAPN may be more advantageous for posterior-lateral renal tumors in terms of OT, EBL, and LOS, but no significant differences were found in WIT, overall complications, major complications, and PSM. Both surgical approaches are safe, but a definitive advantage remains uncertain.

Early results of eTEP access surgery with preperitoneal repair of primary midline ventral hernias and diastasis recti. A 33 patient case series of "PeTEP".

BACKGROUND: This article aims to share the initial experience of the preperitoneal eTEP approach and its potential benefits in a selected group of patients. The eTEP Rives-Stoppa is a proven minimally invasive surgical technique for the treatment of ventral midline and off-midline hernias that has shown to be a solid, durable, and reproducible repair. The preperitoneal eTEP repair is a surgical technique that brings together the extraperitoneal access surgery with a preperitoneal repair for primary midline hernias avoiding posterior rectus sheath division and preservation of the retrorectus space while being able to treat simultaneous diastasis recti. METHODS: The analysis included 33 patients operated with the preperitoneal eTEP approach from September 2022 to September 2023 in patients with primary small to medium (< 4 cm) midline hernias, single or multiple defects with or without diastasis recti. Age, gender, hernia characteristics, operative time, and surgical site occurrences will be discussed, as well as fine details and landmarks in the operative technique. RESULTS: 33 consecutive patients were operated, 19 female (57.5%) and 14 males (42.5%) between 32 and 63 years of age, the most common comorbidity found was obesity (BMI > 30). In 70% of the cases, operative time was 90 min ± 25 min. The average hospital stay was one day, while 12 went home the same day, and so far, no reoccurrences have been reported. CONCLUSIONS: We believe the preperitoneal eTEP approach for small to medium primary midline hernias is an effective and solid repair that combines excellent features of proven surgical techniques and eliminates the need for posterior rectus sheath division while saving the retrorectus space, among other benefits that will be discussed. The reproducibility of the technique remains to be proven.

Extracellular Vesicles of Patients on Peritoneal Dialysis Inhibit the TGF-ß- and PDGF-B-Mediated Fibrotic Processes.

Among patients on peritoneal dialysis (PD), 50-80% will develop peritoneal fibrosis, and 0.5-4.4% will develop life-threatening encapsulating peritoneal sclerosis (EPS). Here, we investigated the role of extracellular vesicles (EVs) on the TGF-ß- and PDGF-B-driven processes of peritoneal fibrosis. EVs were isolated from the peritoneal dialysis effluent (PDE) of children receiving continuous ambulatory PD. The impact of PDE-EVs on the epithelial-mesenchymal transition (EMT) and collagen production of the peritoneal mesothelial cells and fibroblasts were investigated in vitro and in vivo in the chlorhexidine digluconate (CG)-induced mice model of peritoneal fibrosis. PDE-EVs showed spherical morphology in the 100 nm size range, and their spectral features, CD63, and annexin positivity were characteristic of EVs. PDE-EVs penetrated into the peritoneal mesothelial cells and fibroblasts and reduced their PDE- or PDGF-B-induced proliferation. Furthermore, PDE-EVs inhibited the PDE- or TGF-ß-induced EMT and collagen production of the investigated cell types. PDE-EVs contributed to the mesothelial layer integrity and decreased the submesothelial thickening of CG-treated mice. We demonstrated that PDE-EVs significantly inhibit the PDGF-B- or TGF-ß-induced fibrotic processes in vitro and in vivo, suggesting that EVs may contribute to new therapeutic strategies to treat peritoneal fibrosis and other fibroproliferative diseases.