Injectable Self-Oxygenating Cardio-Protective and Tissue Adhesive Silk-Based Hydrogel for Alleviating Ischemia After Mi Injury.

Myocardial infarction (MI) is a significant cardiovascular disease that restricts blood flow, resulting in massive cell death and leading to stiff and noncontractile fibrotic scar tissue formation. Recently, sustained oxygen release in the MI area has shown regeneration ability; however, improving its therapeutic efficiency for regenerative medicine remains challenging. Here, a combinatorial strategy for cardiac repair by developing cardioprotective and oxygenating hybrid hydrogels that locally sustain the release of stromal cell-derived factor-1 alpha (SDF) and oxygen for simultaneous activation of neovascularization at the infarct area is presented. A sustained release of oxygen and SDF from injectable, mechanically robust, and tissue-adhesive silk-based hybrid hydrogels is achieved. Enhanced endothelialization under normoxia and anoxia is observed. Furthermore, there is a marked improvement in vascularization that leads to an increment in cardiomyocyte survival by ≈30% and a reduction of the fibrotic scar formation in an MI animal rodent model. Improved left ventricular systolic and diastolic functions by ≈10% and 20%, respectively, with a ≈25% higher ejection fraction on day 7 are also observed. Therefore, local delivery of therapeutic oxygenating and cardioprotective hydrogels demonstrates beneficial effects on cardiac functional recovery for reparative therapy.

Injectable and self-healing dual crosslinked gelatin/kappa-carrageenan methacryloyl hybrid hydrogels via host-guest supramolecular interaction for wound healing.

Injectable hydrogels based on natural polymers have shown great potential for various tissue engineering applications, such as wound healing. However, poor mechanical properties and weak self-healing ability are still major challenges. In this work, we introduce a host-guest (HG) supramolecular interaction between acrylate-ß-cyclodextrin (Ac-ß-CD) conjugated on methacrylated kappa-carrageenan (MA-κ-CA) and aromatic residues on gelatin to provide self-healing characteristics. We synthesize an MA-κ-CA to conjugate Ac-ß-CD and fabricate dual crosslinked hybrid hydrogels with gelatin to mimic the native extracellular matrix (ECM). The dual crosslinking occurs on the MA-κ-CA backbone through the addition of KCl and photocrosslinking process, which enhances mechanical strength and stability. The hybrid hydrogels exhibit shear-thinning, self-healing, and injectable behavior, which apply easily under a minimally invasive manner and contribute to shear stress during the injection. In-vitro studies indicate enhanced cell viability. Furthermore, scratch assays are performed to examine cell migration and cell-cell interaction. It is envisioned that the combination of self-healing and injectable dual crosslinked hybrid hydrogels with HG interactions display a promising and functional biomaterial platform for wound healing applications.

Ultrasonographically detected hepatosteatosis independently predicts the presence and severity of coronary artery disease.

Background: Nonalcoholic fatty liver disease (NAFLD) has shown to be associated with coronary artery disease (CAD). Objectives: The aim of our study was to evaluate the association between the presence and severity of CAD and NAFLD. Methods: The study group consisted of 153 patients who underwent coronary angiographies. Patients were categorized into CAD and non-CAD groups. CAD severity was determined by the number of CAD-involved arteries and the vessel score multiplied by Gensini score, the latter judging CAD severity. Fatty liver was diagnosed by abdominal ultrasonography (USG), with the patients being categorized by the degree of hepatosteatosis, as Grade 0, Grade 1, and Grade 2-3. Results: Among the whole study population, 47.1% of patients (n=72) were female and 52.9% of patients (n=81) were male. Forty-three patients had normal coronary arteries; 27 patients had non-critical CAD and side branch disease; and 83 patients had clinically significant CAD (stenosis>50%). The rate of CAD and Gensini score were significantly different between Grade 0, 1 and 2-3 hepatosteatosis groups (p<0.05). Patients with CAD had a significantly higher AST level than those without (p< 0.05). Conclusions: Ultrasonographically detected hepatosteatosis independently predicts the presence and severity of CAD.

Immunomodulating Hydrogels as Stealth Platform for Drug Delivery Applications.

Non-targeted persistent immune activation or suppression by different drug delivery platforms can cause adverse and chronic physiological effects including cancer and arthritis. Therefore, non-toxic materials that do not trigger an immunogenic response during delivery are crucial for safe and effective in vivo treatment. Hydrogels are excellent candidates that can be engineered to control immune responses by modulating biomolecule release/adsorption, improving regeneration of lymphoid tissues, and enhancing function during antigen presentation. This review discusses the aspects of hydrogel-based systems used as drug delivery platforms for various diseases. A detailed investigation on different immunomodulation strategies for various delivery options and deliberate upon the outlook of such drug delivery platforms are conducted.

Role of Point-of-Care Lung and Inferior Vena Cava Ultrasound in Clinical Decisions for Patients Presenting to the Emergency Department With Symptoms of Acute Decompensated Heart Failure.

OBJECTIVES: This prospective study was performed to evaluate the diagnostic role of point-of-care lung ultrasound (LUS) and inferior vena cava (IVC) ultrasound in patients with acute decompensated heart failure (ADHF). METHODS: A prospective cohort study was conducted between January 2018 and November 2018 on patients with a diagnosis of ADHF in the emergency department (ED). On admission, LUS findings, inspiratory and expiratory IVC diameters, and the inferior vena cava collapsibility index (IVCCI) were obtained. After therapeutic interventions, third-hour changes in LUS and the IVC index and the treatment response were assessed. RESULTS: Eighty patients were enrolled. Forty-six (58%) patients had an ejection fraction (EF) greater than 40%, and 34 (42%) had an EF of less than 40%. Significant differences were detected between the admission and third-hour inspiratory IVC diameter, expiratory IVC diameter, and IVCCI (P = .001). There was no correlation between the EF and inspiratory IVC diameter (r = -0.03; P = .976), expiratory IVC diameter (r = -109; P = .336), or IVCCI (r = -0.72; P = .523) and between the B-type natriuretic peptide level and inspiratory IVC diameter (r = -0.58; P = .610), expiratory IVC diameter (r = -0.33; P = .774), or IVCCI (r = -0.78; P = .493) either. A comparison of admission and third-hour numbers of B-lines on LUS imaging showed a significant decrease in the number of B-lines in all zones at the end of 3 hours (P = .001). A significant difference existed between the hospitalized and discharged patients with respect to IVC diameters and number of B-lines. CONCLUSIONS: In the ED setting, an assessment of B-lines and measurement of IVC diameters are better markers than the B-type natriuretic peptide level, EF, or chest x-ray for diagnosis of ADHF and can be used to make decisions for hospitalization or discharge from the ED.

Is Bedside End-Tidal CO2 Measurement a Screening Tool to Exclude Pulmonary Embolism in Emergency Department?

BACKGROUND: Pulmonary embolism (PE) is among the most difficult conditions to diagnose in emergency department. The majority of patients thought to have PE are tested positive for D-dimer and subsequently tested with advanced diagnostic modalities. Novel noninvasive tests capable of excluding PE may obviate the need for advanced imaging tests. We studied the role of combined clinical probability assessment and end-tidal carbon dioxide (ETCO2) measurement for diagnosis of possible PE in emergency department. METHODS: We included 100 consecutive subjects suspected to have PE and a positive D-dimer test to study clinical probability of PE and ETCO2 levels. ETCO2 > 34 mm Hg was found to be the best cut-off point for diagnosing PE. PE was ultimately eliminated or diagnosed by spiral computed tomography (CT). RESULTS: Diagnostic performances of tests were as follows: ETCO2 and D-dimer had a sensitivity of 100% and a negative predictive value (NPV) of 100% at the cut-off levels of 34 mm Hg and 500 ng/mL, respectively; Wells score had a sensitivity of 80% and NPV of 69.7% at a score of 4. CONCLUSIONS: ETCO2 alone cannot reliably exclude PE. Combining it with clinical probability, however, reliably and correctly eliminates or diagnoses PE and prevents further testing to be done.