Reinforcing decellularized small intestine submucosa with cellulose acetate nanofibrous and silver nanoparticles as a scaffold for wound healing applications.

BACKGROUND: The formation of chronic wounds accounts for considerable costs in health care systems. Despite the several benefits of decellularized small intestinal submucosa (SIS) as an appropriate scaffold for different tissue regeneration, it has shortcomings such as lack of antibacterial features and inappropriate mechanical properties for skin tissue regeneration. We aimed to examine the efficacy and safety of decellularized SIS scaffold enhanced with cellulose acetate (CA) and silver (Ag) nanoparticles (NPs) for healing full-thickness wounds. METHODS AND RESULTS: The scaffolds were prepared by decellularizing bovine SIS and electrospinning CA/Ag nanoparticles and characterized using a transmission electron microscope (TEM), scanning electron microscope (SEM), tensile testing, and X-ray diffraction. In vivo evaluations were performed using full-thickness excisions covered with sterile gauze as the control group, SIS, SIS/CA, and SIS/CA/Ag scaffolds on the dorsum of twenty male Wistar rats divided into four groups randomly with 21-days follow-up. All in vivo specimens underwent Masson's trichrome (MT) staining for evaluation of collagen deposition, transforming growth factor-ß (TGF-ß) immunohistochemistry (IHC), and Haematoxylin Eosin (H&E) staining. The IHC and MT data were analyzed with the ImageJ tool by measuring the stained area. The TEM results revealed that Ag nanoparticles are successfully incorporated into CA nanofibers. Assessment of scaffolds hydrophilicity demonstrated that the contact angle of SIS/CA/Ag scaffold was the lowest. The in vivo results indicated that the SIS/CA/Ag scaffold had the most significant wound closure. H&E staining of the in vivo specimens showed the formation of epidermal layers in the SIS/CA/Ag group on day 21. The percentage of the stained area of MT and TGF-ß IHC staining's was highest in the SIS/CA/Ag group. CONCLUSION: The decellularized SIS/CA/Ag scaffolds provided the most significant wound closure compared to other groups and caused the formation of epidermal layers and skin appendages. Additionally, the collagen deposition and expression of TGF-ß increased significantly in SIS/CA/Ag group.

3D-printing of alginate/gelatin scaffold loading tannic acid@ZIF-8 for wound healing: In vitro and in vivo studies.

In the present study, ZIF-8 metal-organic framework (MOF) modified with Tannic acid (TA@ZIF-8) was synthesized and impregnated in alginate-gelatin (Alg-Gel) hydrogel. The Alg-Gel scaffolds containing 0, 5, and 10 % of TA@ZIF-8 were fabricated through the 3D printing method specifically denoted as Alg-Gel 0 %, Alg-Gel 5 %, and Alg-Gel 10 %. XRD, FTIR, FESEM, and EDX physically and chemically characterized the synthesized ZIF-8 and TA@ZIF-8 MOFs. Besides, Alg-Gel containing TA@ZIF-8 prepared scaffolds and their biological activity were also evaluated. SEM images verified the nano-size formation of MOFs. Improved swelling and decreased degradation rates after adding TA@ZIF-8 were also reported. Increased compression strength from 0.628 to 1.63 MPa in Alg-Gel 0 % and Alg-Gel 10 %, respectively, and a 2.19 increase in elastic modulus in Alg-Gel 10 % scaffolds were exhibited. Biological activity of scaffolds, including Live-dead and Cell adhesion, antibacterial, in-vivo, and immunohistochemistry assays, demonstrated desirable fibroblast cell proliferation and adhesion, increased bacterial growth inhibition zone, accelerated wound closure and improved expression of anti-inflammatory cytokines in Alg-Gel 10 % scaffolds. The findings of this study confirm that Alg-Gel 10 % scaffolds promote full-thickness wound healing and could be considered a potential candidate for full-thickness wound treatment purposes.

Safety and efficacy of injection of human placenta mesenchymal stem cells derived exosomes for treatment of complex perianal fistula in non-Crohn's cases: Clinical trial phase I.

BACKGROUND AND AIM: A perianal fistula is an abnormal tract that connects anal canal to skin. Current medical and surgical interventions have a high failure rate particularly in complex and refractory cases. MSC-derived exosomes have demonstrated immunomodulatory effects without the conventional complications; hence, in this study, we evaluated the safety of their application for complex perianal fistula. METHODS: Placenta-derived MSCs were cultured, and exosomes were isolated using ultracentrifugation. Exosome injections were administered in the operating room to 11 patients with complex perianal fistula (presence of fistulas for at least 1 year alongside medical and surgical treatment). The patients were followed for 6 months, and the patients were evaluated using physical examination, face-to-face interviews, and magnetic resonance imaging (MRI). RESULTS: Among 11 patients only one did not show any improvement upon physical examination. Five patients showed complete tract resolve. While the discharge was stopped in eight patients, two patients showed only reduction. None of the patients showed any acute or latent allergic reaction or injection related complications. CONCLUSION: Administration of exosomes isolated from MSCs demonstrates safety and a satisfactory therapeutic effect in treatment complex perianal fistulae; therefore, it can be a candidate for future studies and might play a significant role in treatment.

Duodenal Obstruction during Pregnancy.

Intractable vomiting and elevated liver enzymes during pregnancy seem to be associated to the obstetric etiologies; however, other causes such as acute surgical emergencies should be considered. The patient was a 26-year-old woman at 18 weeks of gestation with intractable vomiting, intolerability of oral intake, weight loss, and absence of abdominal pain. Her physical examinations and laboratory tests had no remarkable findings except elevated liver function test (LFT) and hypokalemia. Considering the lab data and normal abdominopelvic ultrasound, magnetic resonance imaging was performed which revealed dilation of the D1-3 and collapse the D4 sections of duodenum. She underwent exploratory laparotomy which confirmed duodenal obstruction caused by Ladd's band. After the Ladd's operation, the patient started oral intake of nutritious, and her LFT decreased to normal ranges. After the last follow-up, she has had gained 18 kg and gave birth at 36 weeks of gestation due to the premature rapture of membranes and delivered a 2 kg small for gestational age otherwise healthy infant. The experience gained from this case was to consider all possibilities (such as small bowel obstruction) and evaluate them in a pregnant patient to consider other causes of nausea, vomiting, and abnormal LFTs in a pregnant patient.

Introduction of a handmade vacuum-assisted sponge drain for the treatment of anastomotic leakage after low anterior rectal resection.

PURPOSE: Anastomotic leakage, a known major postoperative complication, potentially leads to readmission, reoperation, and increased mortality rates in patients, such as rectal cancer patients following a low anterior resection (LAR). Currently, vacuum-assisted closure, as featured by B-Braun (B-Braun Medical B.V.), is already being used for the treatment of gastrointestinal leakages and fistulas. The main aim of this study was to introduce a novel method for creating a vacuum-assisted drain for the treatment of anastomotic leakage after LAR. METHODS: All 10 patients, who underwent LAR surgery from 2018 to 2019, were diagnosed with anastomotic leakage and had received neoadjuvant chemotherapy prior to surgery. Therefore, patients were treated with a handmade vacuum-assisted drain and were revisited every 5 to 7 days for further evaluations and drain replacement until leakage resolution. Physical features of cavity, time of diagnose, and duration of treatment were analyzed correspondingly. The handmade vacuum-assisted sponge drain was prepared for each patient in each session of follow-up. RESULTS: Eight out of 10 patients experienced complete closure of the defect. The mean delay time from the day of operation to the diagnosis of anastomotic leakage was 61.0±80.4 days while the mean time for leakage closure was 117.6±68.3 days. Eventually, 7 cases underwent ileostomy reversal with no complications during a 3-month follow-up. CONCLUSION: In this study, we evaluated the healing process of anastomotic leakage after the usage of a handmade vacuum-assisted sponge drain in a case series method. In our trial, we provided an innovative cost-benefit method easily applicable in the operating room.

Splenic flexure volvulus, a rare etiology of colonic obstruction: Case report.

INTRODUCTION: Splenic flexure volvulus (SFV) occurs as a result of twisting or torsion of a redundant colon around its mesentery. The SFV can be divided into primary and secondary types. PRESENTATION OF CASE: An 82-year-old woman with a previous history of Parkinson's disease, diabetes mellitus and hypertension presented with a primary complaimt of obstipation and progressive abdominal pain. Abdomen was grossly distended and tympanic with generalized tenderness. The rectum was empty on digital rectal examination. Complete blood count showed leuckocytosis and neutrophlia. Plain abdominal X-rays showed distented cecum and ascending colon without any air in the gut distal to the splenic flexure. Regarding her unstable condition even aftre fluid resuscitation, she was transferred to the operating room. SFV was found and the standard left hemicolectomy was performed and bowel continiuity was established with primary anastomis of remained colonic ends. Postoperative period was uneventfull. DISCUSSION: The splenic flexure is strictly attached to the adjacent organs so its volvulus is rare. Most cases of adult SFV have an underlying disease associated with chronic constipation. Diagnosis of volvulus is suspected based on the history, clinical exam, and imaging. The initial and urgent treatment of SFV, if there are no signs of ischemia or perforation, may be conservative with endoscopic detorsion. Gangrenous bowel should not be detorted and should be resected with primary anastomosis or a diverting stoma. CONCLUSION: SFV should be considered as a possible diagnosis of chronic constipation which might be diagnosed with plain abdominal Xray in non emergent condition. Special attention should be given to the medication history of the patient as the anticholinergic agents propagate normal pristaltis.