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.

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.

Broadband Plasmon-Enhanced Four-Wave Mixing in Monolayer MoS2.

Two-dimensional transition-metal dichalcogenide monolayers have remarkably large optical nonlinearity. However, the nonlinear optical conversion efficiency in monolayer transition-metal dichalcogenides is typically low due to small light-matter interaction length at the atomic thickness, which significantly obstructs their applications. Here, for the first time, we report broadband (up to ∼150 nm) enhancement of optical nonlinearity in monolayer MoS2 with plasmonic structures. Substantial enhancement of four-wave mixing is demonstrated with the enhancement factor up to three orders of magnitude for broadband frequency conversion, covering the major visible spectral region. The equivalent third-order nonlinearity of the hybrid MoS2-plasmonic structure is in the order of 10-17 m2/V2, far superior (∼10-100-times larger) to the widely used conventional bulk materials (e.g., LiNbO3, BBO) and nanomaterials (e.g., gold nanofilms). Such a considerable and broadband enhancement arises from the strongly confined electric field in the plasmonic structure, promising for numerous nonlinear photonic applications of two-dimensional materials.

A 28 GHz 2 × 2 Antenna Array with 10 Beams Using Passive SPDT Switch Beamforming Network.

In this paper, a dual-polarized four-port 2 × 2 series fed antenna array operating at 28 GHz with beam-switching capability is proposed. The antenna array uses a simple passive beamforming network to switch the main beam. The presented antenna design is suitable for 5G user equipment and high data rates applications by which it has a compact size with low cost and complexity. The size of the antenna is 37.2 × 37.2 mm2 including the ground plane, and it produces 10 different switched beams by using only two simple 3 dB/90∘ couplers which create the required amplitudes and phase excitations for the antenna elements. A one-port simple feeding mechanism including Peregrine PE42525 SPDT switch modules and a power divider is used to generate and measure the 10 switched beams. The antenna design is implemented on a two-layer 0.203 mm thick low-loss (tanδ = 0.0027) Rogers 4003C substrate, and it has a measured 10 dB impedance bandwidth of 4 GHz (14.3%, from 26 GHz to 30 GHz) for all ports. Measured peak isolation between any dual-polarized ports of the antenna is better than 30 dB. The antenna has an average measured realized gain of 8.9 dBi and around 10 dB side lobe level (SLL) for all beams. The antenna has 3-dB coverage of 80∘ to 90∘ in 2D space and it has a maximum of ±26∘ beam-steering angle. The antenna is designed and simulated using Ansys HFSS and fabricated using regular PCB processing.

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.

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.

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.

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.

Formulating a structural model of self-compassion based on the spiritual intelligence of the students of medical library and information sciences in Iranian Universities of Medical Sciences.

INTRODUCTION: Effective communication is one of the most important factors in advancing the goals of library services and the identifying factors affecting it and having a single model for such factors are of utmost importance. The aim of this study was to develop a structural model of self-compassion measured based on spiritual intelligence (SQ) as factors affecting communication in medical library and information science students. MATERIALS AND METHODS: This was a correlational study done by structural equation modeling method. A total of 290 undergraduate and graduate students of Medical Library and Information Sciences of Iran's Universities of Medical Sciences were selected by simple random sampling. In this study, the data were collected by the Neff's Self-Compassion Scale and the King's Spiritual Intelligence Self-report Inventory. Self-compassion measured based on SQ was tested by goodness-of-fit indices. Statistical analysis was performed using SmartPLS software. RESULTS: The results showed that there was a significant relationship between SQ and self-compassion. Furthermore, the positive values of predictive indices could confirm the self-compassion measured based on SQ. Composite reliability indicated the high reliability of SQ and self-compassion. CONCLUSION: According to the fitting indices of the model, it can be concluded that the self-compassion model has an acceptable fit on the basis of SQ.

The codification of spiritual intelligence measurement model in librarianship and medical information science students of medical universities in Iran.

INTRODUCTION: According to the research mission of the librarianship and information sciences field, it is necessary to have the ability to communicate constructively between the user of the information and information in these students, and it appears more important in medical librarianship and information sciences because of the need for quick access to information for clinicians. Considering the role of spiritual intelligence in capability to establish effective and balanced communication makes it important to study this variable in librarianship and information students. One of the main factors that can affect the results of any research is conceptual model of measure variables. Accordingly, the purpose of this study was codification of spiritual intelligence measurement model. METHODS: This correlational study was conducted through structural equation model, and 270 students were opted from library and medical information students of nationwide medical universities by simple random sampling and responded to the King spiritual intelligence questionnaire (2008). Initially, based on the data, the model parameters were estimated using maximum likelihood method; then, spiritual intelligence measurement model was tested by fit indices. Data analysis was performed by Smart-Partial Least Squares software. RESULTS: Preliminary results showed that due to the positive indicators of predictive association and t-test results for spiritual intelligence parameters, the King measurement model has the acceptable fit and internal correlation of the questionnaire items was significant. Composite reliability and Cronbach's alpha of parameters indicated high reliability of spiritual intelligence model. CONCLUSIONS: The spiritual intelligence measurement model was evaluated, and results showed that the model has a good fit, so it is recommended that domestic researchers use this questionnaire to assess spiritual intelligence.

Prediction of war veteran's mental health based on spiritual well-being, social support and self-efficacy variables: The mediating role of life satisfaction.

INTRODUCTION: The present study aims to provide a model for explaining the mental health of war veterans based on the variables of spiritual well-being, social support, and self-efficacy, with the mediating role of life satisfaction. MATERIALS AND METHODS: The research method was descriptive a correlational. The study samples included 210 veterans, who had records in the Veterans Foundation in Tehran's number one district, Sarallah and Imam Khomeini shelters and Essaar Sports Center in Tehran. They were selected randomly and were asked to respond to questionnaires on mental health, spiritual well-being, life satisfaction, social support, and self-efficacy. The data was analyzed by LISREL software version 8.5, using the path analysis. RESULTS: The results showed that the designed model fitted the data (AGFI = 1.00, RMSEA = 0.00 and NFI = 1.00). In the fitted model, life satisfaction and spiritual well-being directly, and social support indirectly, had a significant relationship with the mediator variable of life satisfaction of the war veterans' mental health. CONCLUSIONS: Veterans with better social support, life satisfaction, and spiritual well-being have better mental health.

Prediction of elders' general health based on positive and negative perfectionism and type-d personality.

BACKGROUND: Multiple factors such as retirement, work disability, social rejection, physical illness and etc., have an impact on general health of the elders. One factor among others is the role of psychological variables. The study is intended to assess the effect of positive and negative perfectionism and type-D personality (distressed) on general health of the elders. METHODS: In this descriptive-correlation study, 80 people (47 male and 33 female) were selected from residents of Nursing Home in Hamadan and Malayer using non-probability (accessible) sampling method. They responded to the questionnaires of type-D Personality, Goldberg and Hillier's General Health and Positive and Negative Perfectionism of Terry-Short et al. RESULTS: Positive perfectionism (r = 0.30) and type-D personality (r = 0.32) had significant correlation with general health. Multiple regression analysis revealed that positive perfectionism and type-D personality could explain at least 49% of the variance in general health. Concerning the variables of negative affectivity, social inhibition and social function, the females' mean was higher than that of males and considering the variables of positive perfectionism, and social functioning, the males' mean was higher than that of females. CONCLUSIONS: Positive perfectionism decreases mental disorder of the elders by creating optimistic attitudes and enhancing social functions. On the other hand, type-D personality, unlike positive perfectionism, makes elders susceptible to physical illness and mental disorder.