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When planned metro disruptions occur, the connectivity of the metro network is severely reduced, impacting the travel of a large number of commuters. The duration of planned metro disruptions varies from a few days to several weeks. To ensure the quality of public transportation services during this period, we propose a bus bridging strategy to address the travel issues of disrupted passengers. This paper introduces a mathematical model for the timetable and bus scheduling of bus bridging when a section of a metro line is planned for disruption, considering two types of buses. In this model, regular buses transfer disrupted passengers whose original destinations are on the disrupted metro section, whereas shuttle buses transfer disrupted passengers whose destinations are on the normal metro line. The model takes into account the impact of metro disruptions on the original passengers of regular buses and aims to minimize passenger transfer waiting time and congestion disutility. The model is solved using a commercial solver and is validated with the case study of Beijing Bus No. 16 and a hypothetical metro line. The results demonstrate that metro disruptions have a significant negative impact on the transfer waiting time and congestion disutility of regular buses. However, the timetable generated by the model effectively mitigates this impact. Additionally, the shuttle bus scheduling solutions generated by the model are not unique, and a specific schedule can be determined based on the shuttle bus costs and service quality. Both the crowding threshold of buses and the maximum number of pickups can reduce the congestion disutility of shuttle buses, but the impact of the crowding threshold is more significant. Practical Applications: This study introduces a model to manage the evacuation of metro commuters during planned service disruptions, such as maintenance closures, announced in advance with a set disruption plan and duration. The model employs a coordinated strategy involving both regular buses and dedicated shuttle buses to evacuate affected passengers efficiently while minimizing disruptions to regular bus passengers. Case study results demonstrate that, although metro disruptions significantly impact regular bus passengers, the optimized timetable developed by the model can alleviate these effects. Passenger waiting time and congestion disutility are developed as key performance indicators. Future applications of this model extend beyond metro disruptions to encompass a wide range of urban transit challenges. For instance, the model can be adapted to manage passenger flow during major city events, natural disasters, or unexpected infrastructure failures. By providing a flexible and scalable framework, this model can support urban planners and transit authorities in enhancing resilience and efficiency in their public transportation systems, ultimately reducing the impact of transit disruptions on daily life. [ABSTRACT FROM AUTHOR]

Background: Targeted protein degradation of neosubstrates plays a crucial role in hematological cancer treatment involving immunomodulatory imide drugs (IMiDs) therapy. Nevertheless, the persistence of inevitable drug resistance and hematological toxicities represents a significant obstacle to their clinical effectiveness. Methods: Phenotypic profiling of a small molecule compounds library in multiple hematological cancer cell lines was conducted to screen for hit degraders. Molecular dynamic-based rational design and cell-based functional assays were conducted to develop more potent degraders. Multiple myeloma (MM) tumor xenograft models were employed to investigate the antitumor efficacy of the degraders as single or combined agents with standard of care agents. Unbiased proteomics was employed to identify multiple therapeutically relevant neosubstrates targeted by the degraders. MM patient-derived cell lines (PDCs) and a panel of solid cancer cell lines were utilized to investigate the effects of candidate degrader on different stage of MM cells and solid malignancies. Unbiased proteomics of IMiDs-resistant MM cells, cell-based functional assays and RT-PCR analysis of clinical MM specimens were utilized to explore the role of BRD9 associated with IMiDs resistance and MM progression. Results: We identified a novel cereblon (CRBN)-dependent lead degrader with phthalazinone scaffold, MGD-4, which induced the degradation of Ikaros proteins. We further developed a novel potent candidate, MGD-28, significantly inhibited the growth of hematological cancer cells and induced the degradation of IKZF1/2/3 and CK1α with nanomolar potency via a Cullin-CRBN dependent pathway. Oral administration of MGD-4 and MGD-28 effectively inhibited MM tumor growth and exhibited significant synergistic effects with standard of care agents. MGD-28 exhibited preferentially profound cytotoxicity towards MM PDCs at different disease stages and broad antiproliferative activity in multiple solid malignancies. BRD9 modulated IMiDs resistance, and the expression of BRD9 was significant positively correlated with IKZF1/2/3 and CK1α in MM specimens at different stages. We also observed pronounced synergetic efficacy between the BRD9 inhibitor and MGD-28 for MM treatment. Conclusions: Our findings present a strategy for the multi-targeted degradation of Ikaros proteins and CK1α against hematological cancers, which may be expanded to additional targets and indications. This strategy may enhance efficacy treatment against multiple hematological cancers and solid tumors. [ABSTRACT FROM AUTHOR]

Most α2-AR agonists derived from dexmedetomidine have few structural differences between them and have no selectivity for α2A/2B-AR or Gi/Gs, which can lead to side effects in drugs. To obtain novel and potent α2A-AR agonists, we performed virtual screening for human α2A-AR and α2B-AR to find α2A-AR agonists with higher selectivity. Compound P300–2342 and its three analogs significantly decreased the locomotor activity of mice (p < 0.05). Furthermore, P300–2342 and its three analogs inhibited the binding of [3H] Rauwolscine with IC50 values of 7.72 ± 0.76 and 12.23 ± 0.11 μM, respectively, to α2A-AR and α2B-AR. In α2A-AR-HEK293 cells, P300–2342 decreased forskolin-stimulated cAMP production without increasing cAMP production, which indicated that P300–2342 activated α2A-AR with coupling to the Gαi/o pathway but without Gαs coupling. P300–2342 exhibited no agonist but slight antagonist activities in α2B-AR. Similar results were obtained for the analogs of P300–2342. The docking results showed that P300–2342 formed π-hydrogen bonds with Y394, V114 in α2A-AR, and V93 in α2B-AR. Three analogs of P300–2342 formed several π-hydrogen bonds with V114, Y196, F390 in α2A-AR, and V93 in α2B-AR. We believe that these molecules can serve as leads for the further optimization of α2A-AR agonists with potentially few side effects. [ABSTRACT FROM AUTHOR]

The α2A adrenergic receptor (α2A-AR) serves as a critical molecular target for sedatives and analgesics. However, α2A-AR ligands with an imidazole ring also interact with an imidazoline receptor as well as other proteins and lead to undesirable effects, motivating us to develop more novel scaffold α2A-AR ligands. For this purpose, we employed an ensemble-based ligand discovery strategy, integrating long-term molecular dynamics (MD) simulations and virtual screening, to identify new potential α2A-AR agonists with novel scaffold. Our results showed that compounds SY-15 and SY-17 exhibited significant biological effects in the preliminary evaluation of protein kinase A (PKA) redistribution assays. They also reduced levels of intracellular cyclic adenosine monophosphate (cAMP) in a dose-dependent manner. Upon treatment of the cells with 100 μM concentrations of SY-15 and SY-17, there was a respective decrease in the intracellular cAMP levels by 63.43% and 53.83%. Subsequent computational analysis was conducted to elucidate the binding interactions of SY-15 and SY-17 with the α2A-AR. The binding free energies of SY-15 and SY-17 calculated by MD simulations were −45.93 and −71.97 kcal/mol. MD simulations also revealed that both compounds act as bitopic agonists, occupying the orthosteric site and a novel exosite of the receptor simultaneously. Our findings of integrative computational and experimental approaches could offer the potential to enhance ligand affinity and selectivity through dual-site occupancy and provide a novel direction for the rational design of sedatives and analgesics. [ABSTRACT FROM AUTHOR]