Human Analogue Research Articles

PDGFRα monoclonal antibody: Assessment of toxicity in juvenile mice administered a murine surrogate antibody of olaratumab.

Olaratumab (Lartruvo™) is a recombinant human IgG1 monoclonal antibody that specifically binds PDGFRα. In order to support use of Lartruvo in pediatric patients, a definitive juvenile animal study in neonatal mice was conducted with a human anti-mouse PDGFRα antibody analog of olaratumab (LSN3338786). A pilot study was used to set doses for the definitive juvenile mouse study. In the definitive study, juvenile mice were administered vehicle, 50, 100, or 150 mg/kg LSN3338786 by subcutaneous (SC) injection every 3 days between postnatal days (PND) 1 and 49, for a total of 17 doses. Blood samples were collected on PND 49 for antibody analysis and toxicokinetic evaluation. Tissues were collected on PND 52 for histopathologic examination. Results of the pilot study indicated that dosing neonatal mice starting on PND 1 via SC administration every 3 days was logistically feasible, produced exposures consistent with prior animal studies, and the selected dose levels were well tolerated by juvenile mice. In the definitive juvenile study, there were no LSN3338786-related deaths, clinical findings, and no effects on mean body weights, body weight gains, or food consumption. Additionally, there were no adverse LSN3338786-related hematology findings, and no macroscopic, organ weight, or microscopic findings of note. The highest dose evaluated, 150 mg/kg, was considered the NOAEL for juvenile toxicity. In conclusion, the juvenile animal studies did not identify any new toxicities or increased sensitivities for the intended pediatric patient population. The use of the surrogate antibody approach in a standard rodent model enabled the de-risking of theoretical concerns for toxicity in pediatric patients due to disruption of the PDGFRα pathway during early human development, such as pulmonary development.

Regulatory Verification by Health Canada of Content in Recombinant Human Insulin, Human Insulin Analog, and Porcine Insulin Drug Products in the Canadian Market Using Validated Pharmacopoeial Methods Over Nonvalidated Approaches.

For diabetes mellitus treatment plans, the consistency and quality of insulin drug products are crucial for patient well-being. Because biologic drugs, such as insulin, are complex heterogeneous products, the methods for drug product evaluation should be carefully validated for use. As such, these criteria are rigorously evaluated and monitored by national authorities. Consequently, reports that describe significantly lower insulin content than their label claims are a concern. This issue was raised by a past publication analyzing insulin drug products available in Canada, and, as a result, consumers and major patient organizations have requested clarification. To address these concerns, this study independently analyzed insulin drug products purchased from local Canadian pharmacies-including human insulin, insulin analogs, and porcine insulin-by compendial and noncompendial reversed-phase high-performance liquid chromatography (RP-HPLC) methods. We demonstrated the importance of using methods fit for purpose when assessing insulin quality. In a preliminary screen, the expected insulin peak was seen in all products except two insulin analogs-insulin detemir and insulin degludec. Further investigation showed that this was not caused by low insulin content but insufficient solvent conditions, which demonstrated the necessity for methods to be adequately validated for product-specific use. When drug products were appropriately assessed for content using the validated type-specific compendial RP-HPLC methods for insulin quantitation, values agreed with the label claim content. Because insulin drug products are used daily by over a million Canadians, it is important that researchers and journals present data using methods fit for purpose and that readers evaluate such reports critically.

Development of a long-acting relaxin analogue, LY3540378, for treatment of chronic heart failure.

Chronic heart failure, a progressive disease with limited treatment options currently available, especially in heart failure with preserved ejection fraction (HFpEF), represents an unmet medical need as well as an economic burden. The development of a novel therapeutic to slow or reverse disease progression would be highly impactful to patients and society. Relaxin-2 (relaxin) is a human hormone regulating cardiovascular, renal, and pulmonary adaptations during pregnancy. A short-acting recombinant relaxin, Serelaxin, demonstrated short-term heart failure symptom relief and biomarker improvement in acute heart failure trials. Here, we present the development of a long-acting relaxin analogue to be tested in the treatment of chronic heart failure. LY3540378 is a long-acting protein therapeutic composed of a human relaxin analogue and a serum albumin-binding VHH domain. LY3540378 is a potent agonist of the relaxin family peptide receptor 1 (RXFP1) and maintains selectivity against RXFP2/3/4 comparable to native relaxin. The half-life of LY3540378 in preclinical species is extended through high affinity binding of the albumin-binding VHH domain to serum albumin. When tested in a single dose administration, LY3540378 elicited relaxin-mediated pharmacodynamic responses, such as reduced serum osmolality and increased renal blood flow in rats. In an isoproterenol-induced cardiac hypertrophy mouse model, treatment with LY3540378 significantly reduced cardiac hypertrophy and improved isovolumetric relaxation time. In a monkey cardiovascular safety study, there were no adverse observations from administration of LY3540378. LY3540378 demonstrated to be a suitable clinical development candidate, and is progressing in clinical trials.

A casework study: The effect of the porcine digestive process on animal carcasses and human teeth

What happens if a human body is fed to pigs? Although a popular notion in the entertainment industry, no scientific published literature exists that documents this porcine feeding behaviour, nor, more importantly, what elements of the cadaver may survive such a process. A study conducted in 2020, born out of a casework enquiry, aimed to investigate the following two questions; Would pigs feed on a human body? And, if so, what could be recovered post feeding event? Kangaroo carcasses, porcine carcasses (as human analogues) and 90 human teeth were prepared, and fed, to two domestic pigs, in a variety of feed scenarios. Biological traces including bones, bone fragments, teeth and tooth fragments were recovered both post-digestion from the faeces of the pigs, as well as uneaten from the porcine enclosure. 29% of all human teeth were recovered from the study; 35% of which were recovered post-digestion from the faeces and 65% were recovered uneaten from the porcine enclosure, Of the recovered human teeth, 81% were deemed suitable for identification by a forensic odontologist. From the 447 bones recovered from the enclosure, 94% could be identified to a bone type and species. From all 3338 bone fragments recovered from the faeces of the pigs, none retained any morphological traits that would allow further intelligence to be generated. Overall, it was found that pigs will feed on human analogues and will consume soft tissue, bones, and human teeth. Biological traces in the form of bones, bone fragments, teeth and tooth fragments may be recovered both post-digestion from the faeces, or from the porcine enclosure. The biological traces can be used for identification of an individual via forensic odontology, identification of a species via forensic anthropology and may be suitable for DNA analysis. The outcomes of this study generated new avenues for investigation in the case and may be used to inform future operational resources.

The first successful desensitization protocol in exenatide allergy: a case report

BackgroundGlucagon-like peptide-1 (GLP-1) receptor agonists are important treatment options in obese patients with type 2 diabetes. To date, few immediate allergic reactions due to GLP-1 receptor agonists were reported. One report revealed that a patient with a level 1 anaphylaxis according to Brighton Criteria due to an exendin based GLP-1 receptor agonist was able to tolerate liraglutide (Human GLP-1 analogue), the alternative GLP-1 receptor agonist. Since exenatide is the only available GLP-1 receptor agonist covered by insurance in Turkey, a drug desensitization protocol, the only therapeutic method in hypersensitivity reactions used in case of absence of an alternative drug, was considered. Here, we report a successful desensitization protocol for the first time in two obese diabetic patients with an immediate hypersensitivity to exenatide.Case presentationThe first patient was a 47 year-old female. She was referred to our outpatient allergy clinic because of a generalized urticaria developed within minutes after the last dose, following a week of an exenatide BID 5 mcg/20 mcl treatment. Although the reaction was sudden onset, it did not meet the Brighton Criteria of anaphylaxis. The second patient was a 46 year-old female. She had a large local immediate injection site reaction that appeared 15 min following an exenatide BID 5 mcg/20 mcl injection. The injection site reaction was not accompanied by a systemic allergic reaction. We performed desensitization with exenatide to two patients who need GLP-1 receptor agonist treatment. Protocol was completed in 7 steps in approximately 3 h, with the aim of reaching the daily dosage of exenatide. Throughout this process, we observed that both cases tolerated the protocol without any complaints or complications. Following the protocol, the patients safely tolerated the treatment for 3 months.ConclusionsWe present the first successful desensitization protocol to exenatide in both local and/or systemic immediate hypersensitivity reactions and indicate the importance of desensitization in patients who do not have alternative therapies.

Human milk phospholipid analog improved the digestion and absorption of 1,3-dioleoyl-2-palmitoyl-glycerol.

The present study investigated the effects of a human milk phospholipid analog (HPLA) on the digestion and absorption of 1,3-dioleoyl-2-palmitoyl-glycerol (OPO). The HPLA contained 26.48% phosphatidylethanolamine (PE), 24.64% phosphatidylcholine (PC), 36.19% sphingomyelin (SM), 6.35% phosphatidylinositol (PI), and 6.32% phosphatidylserine (PS), with 40.51% C16:0, 17.02% C18:0, 29.19% C18:1, and 13.26% C18:2. The HPLA prevented OPO from hydrolysis during the in vitro gastric phase, while it facilitated the digestion of OPO during the in vitro intestinal stage, resulting in the production of large amounts of diglycerides (DAGs) and monoglycerides (MAGs). In vivo experimental results showed that the HPLA might increase the gastric emptying rate of OPO and increase the hydrolysis and absorption of OPO at an early stage of intestinal digestion. Notably, fatty acids in the serum of the OPO group decreased to their initial value at 5 h, while the serum of the OPO + HPLA (OPOH) group still contained a high level of fatty acids indicating that the HPLA was helpful in maintaining serum lipid at a high level, which might be beneficial for sustainably providing energy for babies. The present study provides data support for the potential application of Chinese human milk phospholipid analogs in infant formulas.

Audit of Safety Profile of Drugs Being Used to Treat Elderly Type II Diabetics: Observations from a Tertiary Care Hospital

ABSTRACT Background and Objective: The treatment of elderly people who have developed Type II diabetes is a major challenge. Therefore, this study was conducted to ascertain the drug prescription pattern and the adverse effects of drugs in a tertiary care hospital. Methodology: This was a cross-sectional, observational study. This study was carried out on 164 elderly patients with diabetes mellitus attending inpatient and outpatient of the institute. This study assesses the prescribing pattern of antidiabetic drugs and adverse drugs reaction to the drugs administered. Naranjo-Algorithm Probability of American depositary receipt (ADR) scale and WHO prescribing indicators were used for assessment. This study also identifies the drug utilization in diabetic patients associated with other co-morbidities. Results: Mean age of the patient was 72.5 in both inpatient and outpatient and male:female ratio among inpatient and outpatient 1.5:1 and 1:1.3, respectively. Metformin (biguanide) was the most commonly prescribed antidiabetic drug and was followed by glimepiride. Insulin was used in 65% of inpatient. Potential drug-drug interactions were noted in 71% of inpatient and 50.8% of outpatient. The incidence of ADR observed in this study was3.6%. Conclusion: Metformin and glimepiride were the most common drugs used in both inpatient and outpatient groups. Human regular insulin analog was commonly used in both patients group. The poor reporting in pharmacovigilance although mandated by the Indian Council of Medical Research is falling short; in preempting ADR. Effective pharmacovigilance will improve the quality of life in geriatric patients and would help the treating physicians to steer towards safe and effective healthcare.

The digestion and absorption characteristics of human milk phospholipid analogs: a combination study between in vitro and in vivo.

Phospholipids play a crucial role in the growth and neurodevelopment of infants. Currently, soybean phospholipids (SPLs) are the common phospholipid component in most infant formulas (IFs), which, however, shows an obvious difference with the phospholipid (PL) composition of human milk fat. Therefore, in the present study, human milk phospholipid analogs (HMPAs) were prepared by mimicking the composition of PE, PC, PI, PS, and SM in breast milk phospholipids and the composition of the major fatty acids (C16:0, C18:0, C18:1, and C18:2), and their digestion and absorption characteristics were explored using in vitro and mice models. The prepared HMPA contained 26.48% PE, 24.64% PC, 36.19% SM, 6.35% PI, and 6.32% PS, with 40.51% C16:0, 17.02% C18:0, 29.19% C18:1, and 13.26% C18:2, showing different digestive properties relative to SPL. There was little effect on the physical and chemical properties of HMPA under in vitro gastric conditions. The hydrolysis degree, fatty acids release rate, and average particle size decreasing rate of HMPA was significantly higher than that of SPL during digestion in vitro intestine (P < 0.05), showing better digestive process relative to SPL. In terms of the mice model, HMPA had a higher hydrolysis degree in the intestinal tract. Based on the area under curve (AUC) analysis of serum fatty acids, it was found that despite HMPA being absorbed at a slower rate than SPL, it was absorbed more than SPL. In summary, the digestion and absorption of HMPA were preferred to SPL, and these obtained results might provide a theoretical basis for the development and utilization of HMPA in IF.

Establishment of Stability-Indicating Purity Method Based on the Stress Degradation Behaviour of Human Glucagon-like Peptide-1 Analog Liraglutide using Reverse Phase-Liquid Chromatography

Establishment of Stability-Indicating Purity Method Based on the Stress Degradation Behaviour of Human Glucagon-like Peptide-1 Analog Liraglutide using Reverse Phase-Liquid Chromatography

Promising Role of Silk-Based Biomaterials for Ocular-Based Drug Delivery and Tissue Engineering.

Silk is a wonderful biopolymer that has a long history of medical applications. Surgical cords and medically authorised human analogues made of silk have a long history of use in management. We describe the use of silk in the treatment of eye diseases in this review by looking at the usage of silk fibroin for eye-related drug delivery applications and medication transfer to the eyes. During this ancient art endeavour, a reduced engineering project that employed silk as a platform for medicine delivery or a cell-filled matrix helped reignite interest. With considerable attention, this study explores the present usage of silk in ocular-based drug delivery. This paper also examines emerging developments with the use of silk as a biopolymer for the treatment of eye ailments. As treatment options for glaucoma, diabetic retinopathy, retinitis pigmentosa, and other retinal diseases and degenerations are developed, the trans-scleral route of drug delivery holds great promise for the selective, sustained-release delivery of these novel therapeutic compounds. We should expect a swarm of silk-inspired materials to enter clinical testing and use on the surface as the secrets of silk are unveiled. This article finishes with a discussion on potential silk power, which adds to better ideas and enhanced ocular medicine delivery.

Construction and Validation of a Benchtop Model for Testing of Mechanical Thrombectomy Devices for Pulmonary Embolism.

This study aims to define the process of designing and manufacturing 3D printed and glass models of the pulmonary artery (PA) and utilizing them in a test bed for evaluation of devices for mechanical thrombectomy of pulmonary embolism (PE). Patient derived computed tomography angiography (CTA) images of the PA were digitally converted into a hollowed-out structure and translated into clear 3D printed and glass models. A test bed was created using a peristaltic pump and silicone tubing connected to the models. Human clot analogs were then prepared and injected within the models. Thrombectomy testing was done using clinically used predicates and baseline characteristics of the models were evaluated by independent interventionalists. The mean sizes of the main pulmonary artery (MPA) for the 3D printed model and glass model were 30.4mm and 29.2mm, mimicking those of the patient's PA obtained on CTA. Heterogeneous human clot analogs were created with fibrin composition ranging from 60 to 30%. Mechanical thrombectomy was successfully attempted by independent interventionalists. Both the 3D printed, and glass model were appraised as very good for multiple attributes. A complete test bed using 3D printed and glass models of the PA with human clot analogs was created for testing of mechanical thrombectomy devices for PE.

A Proof-of-Concept Electrochemical Skin Sensor for Simultaneous Measurement of Glial Fibrillary Acidic Protein (GFAP) and Interleukin-6 (IL-6) for Management of Traumatic Brain Injuries

This work demonstrates the use of a noninvasive, sweat-based dual biomarker electrochemical sensor for continuous, prognostic monitoring of a Traumatic Brain Injury (TBI) with the aim of enhancing patient outcomes and reducing the time to treatment after injury. A multiplexed SWEATSENSER was used for noninvasive continuous monitoring of glial fibrillary acidic protein (GFAP) and Interleukin-6 (IL-6) in a human sweat analog and in human sweat. Electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA) were used to measure the sensor response. The assay chemistry was characterized using Fourier Transform Infrared Spectroscopy (FTIR). The SWEATSENSER was able to detect GFAP and IL-6 in sweat over a dynamic range of 3 log orders for GFAP and 2 log orders for IL-6. The limit of detection (LOD) for GFAP detection in the sweat analog was estimated to be 14 pg/mL using EIS and the LOD for IL-6 was estimated to be 10 pg/mL using EIS. An interference study was performed where the specific signal was significantly higher than the non-specific signal. Finally, the SWEATSENSER was able to distinguish between GFAP and IL-6 in simulated conditions of a TBI in human sweat. This work demonstrates the first proof-of-feasibility of a multiplexed TBI marker combined with cytokine and inflammatory marker detection in passively expressed sweat in a wearable form-factor that can be utilized toward better management of TBIs. This is the first step toward demonstrating a noninvasive enabling technology that can enable baseline tracking of an inflammatory response.

Advances in Cardiac Tissue Engineering.

Tissue engineering has paved the way for the development of artificial human cardiac muscle patches (hCMPs) and cardiac tissue analogs, especially for treating Myocardial infarction (MI), often by increasing its regenerative abilities. Low engraftment rates, insufficient clinical application scalability, and the creation of a functional vascular system remain obstacles to hCMP implementation in clinical settings. This paper will address some of these challenges, present a broad variety of heart cell types and sources that can be applied to hCMP biomanufacturing, and describe some new innovative methods for engineering such treatments. It is also important to note the injection/transplantation of cells in cardiac tissue engineering.

Stabilization of human milk fat analog emulsions using milk fat globule membrane material–coated lipid droplets: Structural and physical properties

To mimic the human milk fat globule, milk fat globule membrane (MFGM) was used as an emulsifier to coat the lipid droplets for the preparation of the human milk fat analog emulsions (MFEs). The physical properties of MFEs at different pH and ionic strength and digestion properties were evaluated. The results showed that the encapsulation rate of MFEs was more than 90%, and the zeta potential was −18.53 mV. MFGM fragments were adsorbed at the interface of the lipid droplets and remained stably dispersed in the aqueous phase. Aggregation of MFEs occurred at pH of 3.5–5.3 and NaCl ≥50 mM or CaCl2 ≥ 5 mM. MFEs behaved as viscoelastic liquids at a pH < 6.7 and aggregated at a pH < 4.6, thus forming a gel with increased viscosity. In addition, the digestive characteristics of MFEs were closer to that of human milk. Lipid droplets aggregated during the gastric digestion stage; however, some parts of the globule structure remained until the end of the intestinal digestion stage. This study provides a better understanding of emulsifying and digestive properties of MFGM, and MFGM can be exploited to develop emulsions containing MFGM-coated lipid droplets for the design of infant food.

The ex vivo human translaminar autonomous system to study spaceflight associated neuro-ocular syndrome pathogenesis

Spaceflight-Associated Neuro-ocular Syndrome (SANS) is a significant unexplained adverse reaction to long-duration spaceflight. We employ an ex vivo translaminar autonomous system (TAS) to recreate a human ocular ground-based spaceflight analogue model to study SANS pathogenesis. To recapitulate the human SANS conditions, human ocular posterior segments are cultured in the TAS model for 14 days. Translaminar pressure differentials are generated by simulating various flow rates within intracranial pressure (ICP) and intraocular (IOP) chambers to maintain hydrostatic pressures of ICP: IOP (12:16, 15:16, 12:21, 21:16 mmHg). In addition, optic nerves are mechanically kinked by 6- and 10-degree tilt inserts for the ICP: IOP;15:16 mmHg pressure paradigm. The TAS model successfully maintains various pressure differentials for all experimental groups over 14 days. Post culture, we determine inflammatory and extracellular component expression changes within posterior segments. To further characterize the SANS pathogenesis, axonal transport capacity, optic nerve degeneration and retinal functional are measured. Identifiable pathogenic alterations are observed in posterior segments by morphologic, apoptotic, and inflammatory changes including transport and functional deficits under various simulated SANS conditions. Here we report our TAS model provides a unique preclinical application system to mimic SANS pathology and a viable therapeutic testing device for countermeasures.

Contact ratio and adaptations in the maxillary and mandibular dentoalveolar joints in rats and human clinical analogs

Spatial maps of function-based contact areas and resulting mechanical strains in bones of intact fibrous joints in preclinical small-scale animal models are limited. Functional imaging in situ on intact dentoalveolar fibrous joints (DAJs) in hemimandibles and hemimaxillae harvested from 10 male Sprague-Dawley rats (N = 5 at 12 weeks, N = 5 at 20 weeks) was performed in this study. Physical features including bone volume fraction (BVF), bone pore diameter and pore density, and cementum fraction (CF) of the molars in the maxillary and mandibular joints were evaluated. Biomechanical testing in situ provided estimates of joint stiffness, changes in periodontal ligament spaces (PDL-space) between the molar and bony socket, and thereby localization of contact area in the respective joints. Contact area localization revealed mechanically stressed interradicular and apical regions in the joints. These anatomy-specific contact stresses in maxillary and mandibular joints were correlated with the physical features and resulting strains in interradicular and bony socket compartments.The mandibular joint spaces, in general, were higher than maxillary, and this trend was consistent with age (younger loaded: Mn - 134 ± 55 μm, Mx - 110 ± 47 μm; older loaded: Mn - 122 ± 49 μm, Mx - 105 ± 48 μm). However, a significant decrease (P < 0.05) in mandibular and maxillary joint spaces with age (younger unloaded: Mn - 147 ± 51 μm; Mx - 125 ± 42 μm; older unloaded: Mn - 134 ± 46 μm; Mx - 116 ± 44 μm) was observed. The bone volume fraction (BVF) of mandibular interradicular bone (IR bone) increased significantly with age (P < 0.05) with the percent porosity of coronal mandibular bone lower than its maxillary counterpart. The contact ratio (contact area to total surface area) of maxillary teeth was significantly greater (P < 0.05) than mandibular teeth; both maxillary interradicular and apical contact ratios (IR bone: 41%, 56%; Apical bone: 4%, 12%) increased with age, and were higher than the mandibular (IR bone: 19%, 44%; Apical bone: 1%, 4%) counterpart. Resulting higher but uniform strains in maxillary bone contrasted with lower but higher variance in mandibular strains at a younger age.Anatomy-specific colocalization of physical properties and functional strains in bone provided insights into form-guided adaptive dominance of the maxilla compared to material property-guided adaptive dominance of the mandible. These age-related trends from the preclinical animal model paralleled with age- and tooth position-specific variabilities in mandibular craniofacial bones of adolescent and adult patients following orthodontic treatment.

Effects of Display Modality on Simulated On-Orbit Inspection Performance: Initial Results from Human Exploration Research Analog Campaign 6

To reduce risk in future human spaceflights, free-flying teleoperated inspector robots could be a viable alternative to extravehicular activity inspection operations. Teleoperation depends on accurate operator situation awareness; consequently, a key to successful operations is providing appropriate feedback through an intuitive interface. During each week of a 45-day mission in NASA Human Exploration Research Analog Campaign 6, four crew members perform two simulated telerobotic inspection tasks (Synchronous Inspection task, Asynchronous Inspection task) while using three distinct visual displays (2D, 3D, AR). Preliminary results from Campaign 6 Mission 1 suggest that task performance and efficiency generally improved with each repetition of the task. Performance with the AR display did not show a performance benefit compared to using the 2D or 3D displays. These results are also in general agreement with a prior laboratory study using the same experiment protocol.

Pharmacological reduction of coagulation factor XI reduces macrophage accumulation and accelerates deep vein thrombosis resolution in a mouse model of venous thrombosis

BackgroundDeep vein thrombosis (DVT) and post‐thrombotic syndrome (PTS) remain highly prevalent despite modern medical therapy. Contact activation is a promising target for safe antithrombotic anticoagulation. The anti‐factor XI (FXI) monoclonal antibody 14E11 reduces circulating levels of FXI without compromising hemostasis. The human recombinant analog, AB023, is in clinical development. The role of FXI in mediation of inflammation during DVT resolution is unknown. ObjectivesInvestigate the effects of pharmacological targeting of FXI with 14E11 in an experimental model of venous thrombosis. MethodsAdult wild‐type CD1 mice were treated with subcutaneous anti‐FXI antibody (14E11, 5 mg/kg) versus saline prior to undergoing surgical constriction of the inferior vena cava (IVC). Mice were evaluated at various time points to assess thrombus weight and volume, as well as histology analysis, ferumoxytol enhanced magnetic resonance imaging (Fe‐MRI), and whole blood flow cytometry. Results14E11‐treated mice had reduced thrombus weights and volumes after IVC constriction on day 7 compared to saline‐treated mice. 14E11 treatment reduced circulating monocytes by flow cytometry and macrophage content within thrombi as evaluated by histologic staining and Fe‐MRI. Collagen deposition was increased at day 3 while CD31 and smooth muscle cell actin expression was increased at day 7 in the thrombi of 14E11‐treated mice compared to saline‐treated mice. ConclusionPharmacologic targeting of FXI enhances the early stages of experimental venous thrombus resolution in wild‐type CD1 mice, and may be of interest for future clinical evaluation of the antibody in DVT and PTS.

Astrocytes regulate vascular endothelial responses to simulated deep space radiation in a human organ-on-a-chip model.

Central nervous system (CNS) damage by galactic cosmic ray radiation is a major health risk for human deep space exploration. Simulated galactic cosmic rays or their components, especially high Z-high energy particles such as 56Fe ions, cause neurodegeneration and neuroinflammation in rodent models. CNS damage can be partially mediated by the blood-brain barrier, which regulates systemic interactions between CNS and the rest of the body. Astrocytes are major cellular regulators of blood-brain barrier permeability that also modulate neuroinflammation and neuronal health. However, astrocyte roles in regulating CNS and blood-brain barrier responses to space radiation remain little understood, especially in human tissue analogs. In this work, we used a novel high-throughput human organ-on-a-chip system to evaluate blood-brain barrier impairments and astrocyte functions 1-7 days after exposure to 600 MeV/n 56Fe particles and simplified simulated galactic cosmic rays. We show that simulated deep space radiation causes vascular permeability, oxidative stress, inflammation and delayed astrocyte activation in a pattern resembling CNS responses to brain injury. Furthermore, our results indicate that astrocytes have a dual role in regulating radiation responses: they exacerbate blood-brain barrier permeability acutely after irradiation, followed by switching to a more protective phenotype by reducing oxidative stress and pro-inflammatory cytokine and chemokine secretion during the subacute stage.

Design, Synthesis and Mechanistic Studies of Novel Isatin-Pyrazole Hydrazone Conjugates as Selective and Potent Bacterial MetAP Inhibitors.

Methionine aminopeptidases (MetAPs) are attractive drug targets due to their essential role in eukaryotes as well as prokaryotic cells. In this study, biochemical assays were performed on newly synthesized Isatin-pyrazole hydrazones (PS1–14) to identify potent and selective bacterial MetAPs inhibitors. Compound PS9 inhibited prokaryotic MetAPs, i.e., MtMetAP1c, EfMetAP1a and SpMetAP1a with Ki values of 0.31, 6.93 and 0.37 µM, respectively. Interestingly, PS9 inhibited the human analogue HsMetAP1b with Ki (631.7 µM) about ten thousand-fold higher than the bacterial MetAPs. The in vitro screening against Gram-positive (Enterococcus faecalis, Bacillus subtilis and Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa, Klebsiella pneumonia and Escherichia coli) bacterial strains also exhibited their antibacterial potential supported by minimum bactericidal concentration (MBC), disk diffusion assay, growth curve and time-kill curve experiments. Additionally, PS6 and PS9 had synergistic effects when combined with ampicillin (AMP) and ciprofloxacin (CIP) against selective bacterial strains. PS9 showed no significant cytotoxic effect on human RBCs, HEK293 cells and Galleria mellonella larvae in vivo. PS9 inhibited the growth of multidrug-resistant environmental isolates as it showed the MIC lower than the standard drugs used against selective bacterial strains. Overall, the study suggested PS9 could be a useful candidate for the development of antibacterial alternatives.