Does bioabsorbable mesh reduce hiatal hernia recurrence rates? A meta-analysis.

INTRODUCTION: The use of bioabsorbable mesh at the hiatus is controversial. Long-term data are scant. We evaluated the world literature and performed a meta-analysis to determine if these meshes were effective in reducing recurrence. METHODS: A literature search was performed using PubMed, MEDLINE, and ClinicalKey. We evaluated articles reporting on both Bio-A™ (polyglycolic acid:trimethylene carbonate-PGA:TMC) and Phasix™ (poly-4-hydroxybutyrate-P4HB) used at the hiatus. The DerSimonian-Laird random effects model was used to estimate the overall pooled treatment effect along with a 95% confidence interval (CI). Similar analysis was conducted to compare the clinical outcomes, i.e., recurrence rate, mean surgical time, mean hospital stays and mean follow-up duration between non-Mesh and Mesh group. The I2 statistic was computed to assess the heterogeneity in effect sizes across the studies. RESULTS: A total of 21 studies (12 mesh studies with 963 subjects and 9 non-mesh studies with 617 subjects) were included to conduct the meta-analysis. There was one article reporting outcomes on P4HB mesh (73 subjects) and 11 on PGA:TMC mesh (890 subjects). The bioabsorbable mesh group had a significantly lower recurrence rate compared to the non-mesh group (8% vs. 18%; 95%CI 0.08-0.17), pooled p-value < 0.0001. Surgery time was shorter in the mesh group compared to the non-mesh group (136.4 min vs. 150 min) but not statistically significant (p = 0.54). There tended to be a more extended follow-up period after surgery in the non-mesh group compared to the mesh group (27 vs. 25.8 months, range 10.8-54 months); but not statistically significant (ES: 27.4; 95%CI 21.6-33.3; p = 0.92). CONCLUSIONS: Hiatal hernia repair with bioabsorbable mesh is more effective at reducing hernia recurrence rate in the mid-term than simple suture cruroplasty. Further studies investigating the long-term outcomes and P4HB mesh are needed.

Does the use of bioabsorbable mesh for hiatal hernia repair at the time of bariatric surgery reduce recurrence rates? A meta-analysis.

BACKGROUND: Anywhere from 16% to 37% of patients undergoing bariatric and metabolic surgery are estimated to have a hiatal hernia. To address the lack of long-term data showing the efficacy of bioabsorbable mesh in reducing the recurrence of hiatal hernia in patients who undergo bariatric surgery, we evaluated the world literature and performed a meta-analysis. OBJECTIVE: To evaluate hiatal hernia recurrence rates after placement of bioabsorbable mesh in bariatric patients. SETTING: Meta-analysis of world literature. METHODS: We performed a literature search using PubMed and MEDLINE with search terms including "hiatal hernia recurrence," "bariatric surgery," "bioabsorbable mesh," "Gore BIO-A," and "trimethylene carbonate." Analysis was conducted to compare surgical time, length of stay, recurrence rate, hernia size, and changes in body mass index before and after surgery between mesh-group (MG) and nonmesh (NM) patients. The meta-analysis was described using standardized mean difference, weighted mean difference, effect size, and 95% confidence interval (CI). An I2 statistic was computed to assess heterogeneity. RESULTS: Twelve studies with 1351 patients were included in our meta-analysis. Four studies had both an MG and an NM group. There were 668 patients in the MG and 683 patients in the NM group. Hernia size noted in the NM group (7 cm2) was compared with that in the MG (6.5 cm2) (95% CI: 3.89-9.14; P = .86). The MG had fewer recurrences than the NM group (effect size, 2% versus 14%; 95% CI: -.26 to -.02; P = .027). The average follow-up was 28.8 months for the MG and 32.8 months for the NM group. CONCLUSION: Repair with bioabsorbable mesh at the time of the index bariatric surgery is more effective at reducing the recurrence rate of hiatal hernia than suture cruroplasty. Further studies investigating the long-term outcomes of bioabsorbable mesh placed at the time of bariatric surgery are needed.

Engineering Human Circulating Monocytes/Macrophages by Systemic Deliverable Gene Editing.

Delivery of plasmid DNA to transfect human primary macrophages is extremely difficult, especially for genetic engineering. Engineering macrophages is imperative for the treatment of many diseases including infectious diseases, cancer, neurological diseases, and aging. Unfortunately, plasmid does not cross the nuclear membranes of terminally differentiated macrophages to integrate the plasmid DNA (pDNA) into their genome. To address this issue, we have developed a core-shell nanoparticle (NP) using our newly created cationic lipid to deliver the anti-inflammatory cytokine IL-4 pDNA (IL-4pDNA-NPs). Human blood monocyte-derived macrophages (MDM) were effectively transfected with IL-4pDNA-NPs. IL-4pDNA-NPs were internalized in MDM within 30 minutes and delivered into the nucleus within 2 hours. Exogenous IL-4 expression was detected within 1 - 2 days and continued up to 30 days. Functional IL-4 expression led to M2 macrophage polarization in vitro and in an in vivo mouse model of inflammation. These data suggest that these NPs can protect pDNA from degradation by nucleases once inside the cell, and can transport pDNA into the nucleus to enhance gene delivery in macrophages in vitro and in vivo. In this research, we developed a new method to deliver plasmids into the nucleus of monocytes and macrophages for gene-editing. Introducing IL-4 pDNA into macrophages provides a new gene therapy solution for the treatment of various diseases.