Sodium salicylate as a green fluorescent probe for ultrasensitive determination of vonoprazan fumarate via fluorescence switch off strategy; greenness assessment.

A green, simple and sensitive spectrofluorometric approach for determining vonoprazan fumarate in bulk and pharmaceutical dosage form by turning off the fluorescence of sodium salicylate is developed. The addition of vonoprazan fumarate reduced linearly the fluorescence intensity of 0.4 mM sodium salicylate at λem 408 nm and at λex 330 nm. The approach was found to be linear in the 50.0-3000.0 ng/mL range. The limits of detection and quantification were 10.97 and 33.23 ng/mL, respectively. The presented method proved its suitability in determination of vonoprazan fumarate in its pure and pharmaceutical dosage form. This method employs water as the exclusive solvent and utilizes safe reagents, evaluated using the Analytical Eco Scale, Green Analytical Procedure Index (GAPI), and carbon footprint. In contrast, previous methods relied on toxic reagents and required extended heating times, resulting in higher environmental impact. The novel method not only enhances analytical efficiency but also aligns with green chemistry principles, offering a sustainable solution for routine pharmaceutical analysis.

Oral delivery of Sunitinib malate using carboxymethyl cellulose/poly(acrylic acid-itaconic acid)/Cloisite 30B nanocomposite hydrogel as a pH-responsive carrier.

This work aimed to fabricate a Cloisite 30B-incorporated carboxymethyl cellulose graft copolymer of acrylic acid and itaconic acid hydrogel (Hyd) via a free radical polymerization method for controlled release of Sunitinib malate anticancer drug. The synthesized samples were characterized by FTIR, XRD, TEM, and SEM-dot mapping analyses. The encapsulation efficiency of Hyd and Hyd/Cloisite 30B (6 wt%) was 81 and 93%, respectively, showing the effectiveness of Cloisite 30B in drug loading. An in vitro drug release study showed that drug release from all samples in a buffer solution with pH 7.4 was higher than in a buffer solution with pH 5.5. During 240 min, the cumulative drug release from Hyd/Cloisite 30B (94.97% at pH 7.4) is lower than Hyd (53.71% at pH 7.4). Also, drug-loaded Hyd/Cloisite 30B (6 wt%) demonstrated better antibacterial activity towards S. Aureus bacteria and E. Coli. High anticancer activity of Hyd/Cloisite 30B against MCF-7 human breast cancer cells was shown by the MTT assay, with a MCF-7 cell viability of 23.82 ± 1.23% after 72-hour incubation. Our results suggest that Hyd/Cloisite 30B could be used as a pH-controlled carrier to deliver anticancer Sunitinib malate.

Real-world clinical efficacy of tofacitinib in moderate-to-severe ulcerative colitis.

Tofacitinib is an oral small-molecule Janus kinase (JAK) inhibitor that preferentially inhibits JAK1 and JAK3. Its efficacy in inducing and maintaining remission in ulcerative colitis (UC) as well as its safety profile has been demonstrated in multicenter, randomized, double-blind, placebo-controlled trials. Additionally, real-world studies evaluating the effectiveness and adverse effects of tofacitinib have been conducted, affirming its clinical efficacy in moderate-to-severe UC.

Game changer: How Janus kinase inhibitors are reshaping the landscape of ulcerative colitis management.

Recent advancements in the treatment landscape of ulcerative colitis (UC) have ushered in a new era of possibilities, particularly with the introduction of Janus kinase (JAK)-signal transducer and activator of transcription inhibitors. These novel agents offer a paradigm shift in UC management by targeting key signaling pathways involved in inflammatory processes. With approved JAK inhibitors (JAKis), such as tofacitinib, filgotinib, and upadacitinib, clinicians now have powerful tools to modulate immune responses and gene expression, potentially revolutionizing the treatment algorithm for UC. Clinical trials have demonstrated the efficacy of JAKis in inducing and maintaining remission, presenting viable options for patients who have failed conventional therapies. Real-world data support the use of JAKis not only as first-line treatments but also in subsequent lines of therapy, particularly in patients with aggressive disease phenotypes or refractory to biologic agents. The rapid onset of action and potency of JAKis have broadened the possibilities in the management strategies of UC, offering timely relief for patients with active disease and facilitating personalized treatment approaches. Despite safety concerns, including cardiovascular risks and infections, ongoing research and post-marketing surveillance will continue to refine our understanding of the risk-benefit profile of JAKis in UC management.

Inhibition of CEACAM1 expression in cytokine-activated neutrophils using JAK inhibitors.

OBJECTIVES: Carcinoembryonic-antigen-related cell-adhesion molecule 1 (CEACAM1) is an adhesion molecule that acts as a coinhibitory receptor in the immune system. We previously demonstrated that CEACAM1 is predominantly expressed on peripheral blood neutrophils in patients with RA. The aim of the present study was to investigate the effects of Janus kinase inhibitors (JAKi) on cytokine-activated human neutrophils and CEACAM1 expression. METHODS: Peripheral blood neutrophils were obtained from healthy subjects. Isolated neutrophils were stimulated with tumor necrosis factor-alpha (TNF-α) or granulocyte-macrophage colony-stimulating factor (GM-CSF) in the presence or absence of JAKi. The expression of CEACAM1 in peripheral blood neutrophils was analyzed by flow cytometry. Protein phosphorylation of signal transducer and activator of transcription (STAT)1, STAT3, and STAT5 was assessed by western blot using phospho-specific antibodies. RESULTS: We found that TNF-α-induced CEACAM1 expression was marginally suppressed after pretreatment with pan-JAK inhibitor, tofacitinib. Moreover, TNF-α induced STAT1 and STAT3 phosphorylation at the late stimulation phase (4 to 16 h). The expressions of CEACAM1 on neutrophils were markedly up-regulated by GM-CSF not by interleukin (IL)-6 stimulation. All JAKi inhibited GM-CSF-induced CEACAM1 expressions on neutrophils, however, the inhibitory effects of baricitinib were larger compared to those of tofacitinib or filgotinib. Moreover, CEACAM1 was marginally upregulated in interferon (IFN)-γ stimulated neutrophils. Similarly, JAKi inhibited IFN-γ-induced CEACAM1 expressions on neutrophils. CONCLUSIONS: We demonstrated that JAKi prevent GM-CSF-induced CEACAM1 expression in neutrophils, and JAKi-induced inhibition depends on their selectivity against JAK isoforms. These findings suggest that JAKi can modulate the expression of CEACAM1 in cytokine-activated neutrophils, thereby limiting their activation.

Post-hoc safety/efficacy analyses from pediatric delgocitinib atopic dermatitis trials.

BACKGROUND: Delgocitinib ointment is usually recommended for use in children at a concentration of 0.25%. However, there are no clear criteria for dosing, except that a 0.5% formulation may also be used, depending on symptom severity. Treatment of atopic dermatitis is based on combinations of topical corticosteroids, tacrolimus ointment, and delgocitinib ointment, but there are no reports on the safety of delgocitinib ointment when used in combination with other drugs. METHODS: This is a post-hoc analysis of data from two delgocitinib ointment trials with pediatric atopic dermatitis patients. The efficacy and safety of the 0.25% and 0.5% formulations were compared. Efficacy and safety were evaluated after up to 4 and 56 weeks of treatment, respectively. The safety of delgocitinib ointment when used in combination with topical corticosteroids and/or tacrolimus ointment was investigated. RESULTS: The dose-response relationship was examined according to baseline disease severity. The proportions of subjects with mild disease who achieved cumulative investigator's global assessment of 0 (clear) or 1 (almost clear) were 46.2% (0.25% ointment), 71.4% (0.5% ointment), and 7.7% (vehicle). For subjects with moderate to severe disease, the corresponding proportions were 19.0%, 20.0%, and 0.0%, respectively. No overall differences were seen in the safety profiles of the 0.25% and 0.5% delgocitinib ointment doses, or in the safety profiles of the two doses relating to disease severity or to concomitant use of topical corticosteroids and/or tacrolimus ointment. CONCLUSIONS: These analyses indicate that after up to 4 weeks of treatment, delgocitinib 0.5% ointment may be more effective than the 0.25% dose for mild atopic dermatitis, and that after up to 56 weeks of treatment, delgocitinib is well tolerated in a pediatric trial population when used as prescribed in combination with topical corticosteroids and/or tacrolimus ointment.

Proteomic Analysis Reveals Oxidative Phosphorylation and JAK-STAT Pathways Mediated Pathogenesis of Pemphigus Vulgaris.

Pemphigus vulgaris (PV) stands as a rare autoimmune bullous disease, while the precise underlying mechanism remains incompletely elucidated. High-throughput proteomic methodologies, such as LC-MS/MS, have facilitated the quantification and characterisation of proteomes from clinical skin samples, enhancing our comprehension of PV pathogenesis. The objective of this study is to elucidate the signalling mechanisms underlying PV through proteomic analysis. Proteins and cell suspension were extracted from skin biopsies obtained from both PV patients and healthy volunteers and subsequently analysed using LC-MS/MS and scRNA-seq. Cultured keratinocytes were treated with PV serum, followed by an assessment of protein expression levels using immunofluorescence and western blotting. A total of 880, 605, and 586 differentially expressed proteins (DEPs) were identified between the lesion vs. control, non-lesion vs. control, and lesion vs. non-lesion groups, respectively. The oxidative phosphorylation (OXPHOS) pathway showed activation in PV. Keratinocytes are the major cell population in the epidermis and highly expressed ATP5PF, ATP6V1G1, COX6B1, COX6A1, and NDUFA9. In the cellular model, there was a notable increase in the expression levels of OXPHOS-related proteins (V-ATP5A, III-UQCRC2, II-SDHB, I-NDUFB8), along with STAT1, p-STAT1, and p-JAK1. Furthermore, both the OXPHOS inhibitor metformin and the JAK1 inhibitor tofacitinib demonstrated therapeutic effects on PV serum-induced cell separation, attenuating cell detachment. Metformin notably reduced the expression of V-ATP5A, III-UQCRC2, II-SDHB, I-NDUFB8, p-STAT1, p-JAK1, whereas tofacitinib decreased the expression of p-STAT1 and p-JAK1, with minimal impact on the expression of V-ATP5A, III-UQCRC2, II-SDHB, and I-NDUFB8. Our results indicate a potential involvement of the OXPHOS and JAK-STAT1 pathways in the pathogenesis of PV.

Current Overview of the Biology and Pharmacology in Sugen/Hypoxia-Induced Pulmonary Hypertension in Rats.

The Sugen 5416/hypoxia (Su/Hx) rat model of pulmonary arterial hypertension (PAH) demonstrates most of the distinguishing features of PAH in humans, including increased wall thickness and obstruction of the small pulmonary arteries along with plexiform lesion formation. Recently, significant advancement has been made describing the epidemiology, genomics, biochemistry, physiology, and pharmacology in Su/Hx challenge in rats. For example, there are differences in the overall reactivity to Su/Hx challenge in different rat strains and only female rats respond to estrogen treatments. These conditions are also encountered in human subjects with PAH. Also, there is a good translation in both the biochemical and metabolic pathways in the pulmonary vasculature and right heart between Su/Hx rats and humans, particularly during the transition from the adaptive to the nonadaptive phase of right heart failure. Noninvasive techniques such as echocardiography and magnetic resonance imaging have recently been used to evaluate the progression of the pulmonary vascular and cardiac hemodynamics, which are important parameters to monitor the efficacy of drug treatment over time. From a pharmacological perspective, most of the compounds approved clinically for the treatment of PAH are efficacious in Su/Hx rats. Several compounds that show efficacy in Su/Hx rats have advanced into phase II/phase III studies in humans with positive results. Results from these drug trials, if successful, will provide additional treatment options for patients with PAH and will also further validate the excellent translation that currently exists between Su/Hx rats and the human PAH condition.

Efficacy and safety of Vonoprazan-based treatment of Helicobacter pylori infection: a systematic review and network meta-analysis.

OBJECTIVE: The aim of this study was to evaluate the effectiveness and safety of the nine most widely studied Vonoprazan (VPZ)-based treatment regimens along with traditional Proton pump inhibitor (PPI)-based treatment regimens in eradicating Helicobacter pylori (H. pylori) infection. DESIGN: Through searching PubMed, Embase, Cochrane Library, Web of Science, we exclusively included randomized controlled trials (RCTs) to investigate the efficacy of VPZ-based and PPI-based therapies for H. pylori infection. The included studies were evaluated for methodological quality using the Cochrane bias risk assessment tool, and the data analysis software was used to analyze the data accordingly. RESULTS: The RCTs were collected from the earliest available date up to August 2023. Twenty-one RCTs were included, with a total sample size of 5481. The results of the network meta-analysis showed that the eradication rate of the VPZ-based quadruple 14-day (VPZ-Q14) treatment regimen in Intention-to-treat (ITT) analysis was the highest (SUCRA: 0.874); The eradication rate of the VPZ-based quadruple 10-day (VPZ-Q10) treatment plan in Per-protocol (PP) analysis was the highest (SUCRA: 0.849). All regimens were well tolerated without significant differences. According to the probability ranking of safety, high-dose VPZ-based dual 14-day therapy (H-VPZ-D14) ranked first in SUCRA, reaching 0.952. This indicates that H-VPZ-D14 treatment is the safest with a relatively low incidence of adverse effect. Therefore, VPZ-based therapies not only have a higher eradication rate, but also possess satisfactory safety. CONCLUSION: Compared with traditional PPI-based therapies, VPZ-based therapies have shown superior eradication effects. Based on the Ranking Plot of the Network, the VPZ-Q14 or VPZ-Q10 treatment regimen for H. pylori has a higher eradication rate and acceptable differences compared to other treatment regimens. In addition, for regions with high antibiotic resistance rates, we recommend a 14-day quadruple therapy with bismuth based on VPZ.

Effect of isavuconazole on the pharmacokinetics of sunitinib and its mechanism.

BACKGROUND: Sunitinib, a newly developed multi-targeted tyrosine kinase inhibitor (TKI), has become a common therapeutic option for managing advanced renal cell carcinoma (RCC). Examining the mechanism underlying the interaction between sunitinib and isavuconazole was the aim of this effort. METHODS: The concentrations of sunitinib and its primary metabolite, N-desethyl sunitinib, were analyzed and quantified using ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Our study evaluated the potential interaction between isavuconazole and sunitinib using rat liver microsomes (RLM), human liver microsomes (HLM), and in vivo rat models. For the in vivo study, two groups (n = 5) of Sprague-Dawley (SD) rats were randomly allocated to receive sunitinib either with or without co-administration of isavuconazole. Additionally, the effects of isavuconazole on the metabolic stability of sunitinib and N-desethyl sunitinib were studied in RLM in vitro. RESULTS: Our findings demonstrated that in RLM, isavuconazole exhibited a mixed non-competitive and competitive inhibition mechanism, with an IC50 (half maximal inhibitory concentration) value of 1.33 µM. Meanwhile, in HLM, isavuconazole demonstrated a competitive inhibition mechanism, with an IC50 of 5.30 µM. In vivo studies showed that the presence of isavuconazole significantly increased the pharmacokinetic characteristics of sunitinib, with the AUC(0→t), AUC(0→∞), and Tmax rising to approximately 211.38%, 203.92%, and 288.89%, respectively, in contrast to the control group (5 mg/kg sunitinib alone). The pharmacokinetic characteristics of the metabolite N-desethyl sunitinib in the presence of isavuconazole remained largely unchanged compared to the control group. Furthermore, in vitro metabolic stability experiments revealed that isavuconazole inhibited the metabolic processing of both sunitinib and N-desethyl sunitinib. CONCLUSIONS: Isavuconazole had a major impact on sunitinib metabolism, providing fundamental information for the precise therapeutic administration of sunitinib.

An Overview on the Synthesis of Lamellarins and Related Compounds with Biological Interest.

Lamellarins are natural products with a [3,4]-fused pyrrolocoumarin skeleton possessing interesting biological properties. More than 70 members have been isolated from diverse marine organisms, such as sponges, ascidians, mollusks, and tunicates. There is a continuous interest in the synthesis of these compounds. In this review, the synthetic strategies for the synthesis of the title compounds are presented along with their biological properties. Three routes are followed for the synthesis of lamellarins. Initially, pyrrole derivatives are the starting or intermediate compounds, and then they are fused to isoquinoline or a coumarin moiety. Second, isoquinoline is the starting compound fused to an indole moiety. In the last route, coumarins are the starting compounds, which are fused to a pyrrole moiety and an isoquinoline scaffold. The synthesis of isolamellarins, azacoumestans, isoazacoumestans, and analogues is also described. The above synthesis is achieved via metal-catalyzed cross-coupling, [3 + 2] cycloaddition, substitution, and lactonization reactions. The title compounds exhibit cytotoxic, multidrug resistance (MDR), topoisomerase I-targeted antitumor, anti-HIV, antiproliferative, anti-neurodegenerative disease, and anti-inflammatory activities.

Facile One-Pot Preparation of Polypyrrole-Incorporated Conductive Hydrogels for Human Motion Sensing.

Conductive hydrogels have been widely used in soft robotics, as well as skin-attached and implantable bioelectronic devices. Among the candidates of conductive fillers, conductive polymers have become popular due to their intrinsic conductivity, high biocompatibility, and mechanical flexibility. However, it is still a challenge to construct conductive polymer-incorporated hydrogels with a good performance using a facile method. Herein, we present a simple method for the one-pot preparation of conductive polymer-incorporated hydrogels involving rapid photocuring of the hydrogel template followed by slow in situ polymerization of pyrrole. Due to the use of a milder oxidant, hydrogen peroxide, for polypyrrole synthesis, the photocuring of the hydrogel template and the growing of polypyrrole proceeded in an orderly manner, making it possible to prepare conductive polymer-incorporated hydrogels in one pot. The preparation process is facile and extensible. Moreover, the obtained hydrogels exhibit a series of properties suitable for biomedical strain sensors, including good conductivity (2.49 mS/cm), high stretchability (>200%), and a low Young's modulus (~30 kPa) that is compatible with human skin.

Improved N-phenylpyrrolamide inhibitors of DNA gyrase as antibacterial agents for high-priority bacterial strains.

In this work, we describe an improved series of N-phenylpyrrolamide inhibitors that exhibit potent activity against DNA gyrase and are highly effective against high-priority gram-positive bacteria. The most potent compounds show low nanomolar IC50 values against Escherichia coli DNA gyrase, and in addition, compound 7c also inhibits E. coli topoisomerase IV in the nanomolar concentration range, making it a promising candidate for the development of potent dual inhibitors for these enzymes. All tested compounds show high selectivity towards the human isoform DNA topoisomerase IIα. Compounds 6a, 6d, 6e and 6f show MIC values between 0.031 and 0.0625 µg/mL against vancomycin-intermediate S. aureus (VISA) and Enterococcus faecalis strains. Compound 6g shows an inhibitory effect against the methicillin-resistant S. aureus strain (MRSA) with a MIC of 0.0625 µg/mL and against the E. faecalis strain with a MIC of 0.125 µg/mL. In a time-kill assay, compound 6d showed a dose-dependent bactericidal effect on the MRSA strain and achieved bactericidal activity at 8 × MIC after 8 h. The duration of the post-antibiotic effect (PAE) on the MRSA strain for compound 6d was 2 h, which corresponds to the PAE duration for ciprofloxacin. The compounds were not cytotoxic at effective concentrations, as determined in an MTS assay on the MCF-7 breast cancer cell line.

Vonoprazan Dual or Triple Therapy Versus Bismuth-Quadruple Therapy as First-Line Therapy for Helicobacter pylori Infection: A Three-Arm, Randomized Clinical Trial.

BACKGROUND: We compared efficacy of vonoprazan-dual or triple therapies and bismuth-quadruple therapy for treatment-naive Helicobacter pylori (HP) infection in Southern China, where primary resistance rates of clarithromycin and levofloxacin are >30%. METHODS: This was an investigator-initiated, three-arm, randomized clinical trial in Southern China. Between March 2022 and August 2023, treatment-naïve HP-infected adults were randomly assigned to receive one of three 14-day regimens (1:1:1 ratio): vonoprazan-dual (VA-dual; vonoprazan 20 mg twice daily and amoxicillin 1 g thrice daily), vonoprazan-triple (VAC-triple; vonoprazan 20 mg/amoxicillin 1 g/clarithromycin 500 mg twice daily), or bismuth-quadruple therapy containing bismuth, esomeprazole, tetracycline, and metronidazole. Primary outcome was noninferiority in HP eradication, evaluated by UBT 4-6 weeks post-treatment by intention-to-treat (ITT) and per-protocol (PP) analysis (based on subjects who completed 14-day treatment and rechecked UBT). Bonferroni-adjusted p-value of <0.017 was used to determine statistical significance. RESULTS: A total of 298 subjects (mean age: 35.7 ± 8.4 years; male: 134 [45.0%]; VC-dual: 100, VAC-triple: 98, bismuth-quadruple: 100) were enrolled, and 292 (98.0%) had UBT rechecked. ITT analysis showed that both VA-dual (eradication rate of 96.0%) and VAC-triple therapies (95.9%) were noninferior to bismuth-quadruple therapy (92.0%) (difference: 4.0%, 95% CI: -2.9% to 11.5%, p < 0.001; and 3.9%, 95% CI: -3.1% to 11.5%, p < 0.001, respectively). PP analysis also revealed noninferiority (96.7% or 96.7% vs. 97.4%, with difference: -2.9% and -2.9%, p = 0.009 and 0.010, respectively). The frequency of adverse events was 39.0%, 56.1%, and 71.0% in VA-dual, VAC-triple, and bismuth-quadruple therapies, respectively. CONCLUSIONS: VA-dual and VA-triple therapies are highly effective and noninferior to bismuth-quadruple therapy in Southern China. Given the lower adverse effects and fewer antibiotic use, VA-dual therapy is the preferred first-line treatment for HP infection. TRIAL REGISTRATION: Chinese Clinical Trial Registry (No. ChiCTR2200056375). Registered on February 4, 2022, https://www.chictr.org.cn/showproj.aspx?proj=14131.

Transcriptomic and functional analyses on a Botrytis cinerea multidrug-resistant (MDR) strain provides new insights into the potential molecular mechanisms of MDR and fitness.

Botrytis cinerea is a notorious pathogen causing pre- and post-harvest spoilage in many economically important crops. Excessive application of site-specific fungicides to control the pathogen has led to the selection of strains possessing target site alterations associated with resistance to these fungicides and/or strains overexpressing efflux transporters associated with multidrug resistance (MDR). MDR in B. cinerea has been correlated with the overexpression of atrB and mfsM2, encoding an ATP-binding cassette (ABC) and a major facilitator superfamily (MFS) transporter, respectively. However, it remains unknown whether other transporters may also contribute to the MDR phenotype. In the current study, the transcriptome of a B. cinerea multidrug-resistant (MDR) field strain was analysed upon exposure to the fungicide fludioxonil, and compared to the B05.10 reference strain. The transcriptome of this field strain displayed significant differences as compared to B05.10, including genes involved in sugar membrane transport, toxin production and virulence. Among the induced genes in the field strain, even before exposure to fludioxonil, were several putatively encoding ABC and MFS transmembrane transporters. Overexpression of a highly induced MFS transporter gene in the B05.10 strain led to an increased tolerance to the fungicides fluopyram and boscalid, indicating an involvement in efflux transport of these compounds. Overall, the data from this study give insights towards better understanding the molecular mechanisms involved in MDR and fitness cost, contributing to the development of more efficient control strategies against this pathogen.

Stonikacidin A, an Antimicrobial 4-Bromopyrrole Alkaloid Containing L-Idonic Acid Core from the Northwestern Pacific Marine Sponge Lissodendoryx papillosa.

Stonikacidin A (1), the first representative of a new class of 4-bromopyrrole alkaloids containing an aldonic acid core, was isolated from the marine sponge Lissodendoryx papillosa. The compound is named in honor of Prof. Valentin A. Stonik, who is one of the outstanding investigators in the field of marine natural chemistry. The structure of 1 was determined using NMR, MS analysis, and chemical correlations. The L-idonic acid core was established by the comparison of GC, NMR, MS, and optical rotation data of methyl-pentaacetyl-aldonates obtained from the hydrolysis products of 1 and standard hexoses. The L-form of the idonic acid residue in 1 was confirmed by GC analysis of pentaacetate of (S)-2-butyl ester of the hydrolysis product from 1 and compared with corresponding derivatives of L- and D-idonic acids. The biosynthetic pathway for stonikacidin A (1) was proposed. The alkaloid 1 inhibited the growth of Staphylococcus aureus and Escherichia coli test strains, as well as affected the formation of S. aureus and E. coli biofilms. Compound 1 inhibited the activity of sortase A. Molecular docking data showed that stonikacidin A (1) can bind with sortase A due to the interactions between its bromine atoms and some amino acid residues of the enzyme.

Multimodal analyses of immune cells during bone repair identify macrophages as a therapeutic target in musculoskeletal trauma.

Musculoskeletal traumatic injuries (MTI) involve soft tissue lesions adjacent to a bone fracture leading to fibrous nonunion. The impact of MTI on the inflammatory response to fracture and on the immunomodulation of skeletal stem/progenitor cells (SSPCs) remains unknown. Here, we used single-nucleus transcriptomic analyses to describe the immune cell dynamics after bone fracture and identified distinct macrophage subsets with successive pro-inflammatory, pro-repair and anti-inflammatory profiles. Concurrently, SSPCs transition via a pro- and anti-inflammatory fibrogenic phase of differentiation prior to osteochondrogenic differentiation. In a preclinical MTI mouse model, the injury response of immune cells and SSPCs is disrupted leading to a prolonged pro-inflammatory phase and delayed resolution of inflammation. Macrophage depletion improves bone regeneration in MTI demonstrating macrophage involvement in fibrous nonunion. Finally, pharmacological inhibition of macrophages using the CSF1R inhibitor Pexidartinib ameliorates healing. These findings reveal the coordinated immune response of macrophages and skeletal stem/progenitor cells as a driver of bone healing and as a primary target for the treatment of trauma-associated fibrosis.

Investigation of the Nonradiative Photoprocesses of Unnatural DNA Base: 7-(2-Thienyl)-imidazo[4,5-b]pyridine (Ds)─A Computational Study.

7-(2-Thienyl)-imidazo[4,5-b]pyridine (Ds) is an unnatural nucleic acid that forms a stable pair with pyrrole-2-carbaldehyde (Pa) in DNA. This Ds-Pa pair gets stabilized via van der Waals interaction and shape fitting. In our previous study [Ghosh, P. J. Phys. Chem. A 2021, 125, 5556-5561], we investigated the nonradiative photoprocesses of the unnatural DNA base Pa, and also there are some studies on its stability and reactivity in the ground state. But, to consider it as a good unnatural base pair, one has to understand its stability not only in the ground state but also in the excited states after absorbing ultraviolet (UV) radiation. Therefore, in this study, the excited-state photoprocesses of Ds on UV irradiation and its nonradiative decay channels have been investigated using state-of-the-art multireference methods, and this investigation finally leads the molecule to access the minimum energy crossing point (MECP) via a downhill pathway.