Activity

  • Hartvigsen Lambertsen posted an update 1 day, 22 hours ago

    Thrombosis is a life-threatening pathological condition in which blood clots form in blood vessels, obstructing or interfering with blood flow. Thrombolytic agents (TAs) are enzymes that can catalyze the conversion of plasminogen to plasmin to dissolve blood clots. The plasmin formed by TAs breaks down fibrin clots into soluble fibrin that finally dissolves thrombi. Several TAs have been developed to treat various thromboembolic diseases, such as pulmonary embolisms, acute myocardial infarction, deep vein thrombosis, and extensive coronary emboli. However, systemic TA administration can trigger non-specific activation that can increase the incidence of bleeding. Moreover, protein-based TAs are rapidly inactivated upon injection resulting in the need for large doses. To overcome these limitations, various types of nanocarriers have been introduced that enhance the pharmacokinetic effects by protecting the TA from the biological environment and targeting the release into coagulation. The nanocarriers show increasing half-life, reducing side effects, and improving overall TA efficacy. Berzosertib molecular weight In this work, the recent advances in various types of TAs and nanocarriers are thoroughly reviewed. Various types of nanocarriers, including lipid-based, polymer-based, and metal-based nanoparticles are described, for the targeted delivery of TAs. This work also provides insights into issues related to the future of TA development and successful clinical translation.Large macrocyclic peptides can achieve surprisingly high membrane permeability, although the properties that govern permeability in this chemical space are only beginning to come into focus. We generated two libraries of cyclic decapeptides with stable cross-β conformations, and found that peptoid substitutions within the β-turns of the macrocycle preserved the rigidity of the parent scaffold, whereas peptoid substitutions in the opposing β-strands led to “chameleonic” species that were rigid in nonpolar media but highly flexible in water. Both rigid and chameleonic compounds showed high permeability over a wide lipophilicity range, with peak permeabilities differing significantly depending on scaffold rigidity. Our findings indicate that modulating lipophilicity can be used to engineer favorable ADME properties into both rigid and flexible macrocyclic peptides, and that scaffold rigidity can be used to tune optimal lipophilicity.

    Motor abnormalities of pharyngeal contraction or upper esophageal sphincter (UES) relaxation can lead to swallowing problems.

    We reviewed high-resolution esophageal manometry of children ≤18years and classified into two groups based on the results of videofluoroscopic study of swallow (VFSS), as normal or abnormal. The UES metrics (integrated relaxation pressure [IRP], resting pressure [URP], and nadir pressure [UNP]), as well as peak pharyngeal pressure (velopharyngeal and meso-hypopharyngeal), were analyzed.

    UES metrics There were 142 and 19 subjects in the normal and abnormal groups, respectively. In the normal group, the median UES-IRP at 0.2, 0.4, 0.6, 0.8seconds, URP, and UNP were 1.0, 4.0, 11.0, 18.0, 53.5, and -1.0mmHg while in the abnormal group were 10.0, 13.0, 21.0, 25.5, 47.0, and 8.0mmHg. The UES-IRP at 0.2, 0.4, 0.6seconds, and UNP was significantly higher in the abnormal group. Pharyngeal metrics We included 58 subjects in normal and 10 subjects in the abnormal group. The median of peak vrmal VFSS.A 74-year old female patient presented with a 3-week history of fever, general weakness, and later developed complete heart block. On admission, the patient was febrile (temperature of 39°C) and tachypnoeic (respiratory rate of 29/min) with oxygen saturation of 95% on 2 L of oxygen. Her heart rate was 60 beats/min (VVI pacing), arterial blood pressure was 135/60 mm Hg and the Glasgow Coma Scale was 15. On chest auscultation, she had a harsh systolic murmur over her left precordium and bilateral rales. Blood tests demonstrated moderate anemia (hemoglobin of 95 g/L), leucocytosis (white blood cell count of 13.13 x 10^9/L), hypoalbuminemia (albumin concentration of 18 g/L), normal liver function tests and creatinine clearance of 45 ml/min. Computed tomography aortography demonstrated an irregular mass arising from the aortic root that extended into the right atrium (RA) and a fistulous tract (the Gerbode defect) between the left ventricular outflow tract (LVOT) and the right ventricle (RV). Transoesophageal echocardiography showed large vegetation in the RA and left to right cardiac shunt through the Gerbode defect from the LVOT to the RA and the RV. Using cardiopulmonary bypass, the patient underwent resection of the aortic cusps, debridement of the aortic root, septal and anterior leaflets of the tricuspid valve, and the membranous septum. The Gerbode defect was closed with an autologous pericardial patch, then a sliding annuloplasty of the septal leaflet of the tricuspid valve was performed. Finally, the aortic root was replaced with a 23 mm Freestyle xenograft.Water enriched with oxygen-18 (H218 O) is a potential tracer for evaluating the sources of glucose and glycogen synthesis since it is incorporated into specific sites of glucose-6-phosphate via specific enzyme-mediated exchange/addition mechanisms. Unlike 2 H, 18 O does not experience significant isotope effects for any of these processes. Therefore, H218 O might provide more precise estimates of endogenous carbohydrate synthesis compared with deuterated water provided that positional 18 O enrichments of glucose can be measured. As a proof of concept, H218 O was incorporated into a well characterized hemolysate model of sugar phosphate metabolism and 13 C NMR was applied to quantify positional 18 O enrichment of glucose-6-phosphate oxygens. Human erythrocyte hemolysate preparations were incubated overnight at 37 °C with a buffer containing sugar phosphate precursors and 20% (n = 5) and 80% (n = 1) H218 O. Enrichment of glucose-6-phosphate was analyzed by 13 C NMR analysis of 18 O-shifted versus unshifted signals following derivatization to monoacetone glucose (MAG). 13 C NMR MAG spectra from hemolysate revealed resolved 18 O-shifted signals in Positions 1-5. Mean 18 O enrichments were 16.4 ± 1.6% (Position 1), 13.3 ± 1.3% (Position 2), 4.1 ± 1.1% (Position 3), 12.6 ± 0.8% (Position 4), 10.7 ± 1.4% (Position 5), and no detectable enrichment of Position 6. No 18 O-shifted glucose-6-phosphate signals were detected in preparations containing sugar phosphate precursors only. H218 O is incorporated into Positions 1-5 of glucose-6-phosphate in accordance with spontaneous aldose hydration and specific enzymatic reaction mechanisms. This provides a basis for its deployment as a tracer for glucose and glycogen biosynthesis.