Harnessing spatial transcriptomics for advancing plant regeneration research.

Song et al. utilized spatial transcriptomics to study the molecular characteristics of various cells - such as shoot primordia and chlorenchyma cells - in tomato callus during shoot regeneration. This research enhances our knowledge of shoot regeneration and demonstrates the potential of spatial transcriptomics in advancing plant biology.

Polydopamine functionalized polyurethane shape memory sponge with controllable expansion performance triggered by near-infrared light for incompressible hemorrhage control.

Uncontrolled expansion of shape memory sponges face a significant challenge in the treatment of lethal incompressible hemorrhage, which can lead to blood overflow or damage to the surrounding tissue. Herein, we developed a polydopamine functionalized polyurethane shape memory sponge (PDA-TPI-PU) with a controllable degree of expansion by near-infrared (NIR) light-triggered stimulation for the treatment of incompressible hemorrhage. The sponge has excellent liquid absorption performance and robust mechanical strength as well as good photothermal conversion ability. Under NIR light of 0.32 W/cm2, the maximum recovery rate of the fixed-shape compression sponge was 91% within 25 s in air and 80% within 25 s in blood. In the SD rat liver penetrating injury model, compared with commercial medical gelatin sponge and PVA sponge, the PDA-TPI-PU sponge could effectively control the bleeding under the NIR light irradiation and did not cause excessive compression of the wound. The sponge with these characteristics shows potential application prospects as a hemostatic material.

Gelatin Methacryloyl-Based Sponge with Designed Conical Microchannels for Rapidly Controlling Hemorrhage and Theoretical Verification.

It remains a challenge to develop effective hemostatic products in battlefield rescue for noncompressible massive hemorrhage. Some previous research had concentrated on the modification of different materials to improve the hemostasis ability of sponges. Herein, to investigate the relationship between the taper of microchannels and hemostatic performance of porous sponges, gelatin methacryloyl-based sponges with designed conical microchannels and a disordered porous structure were prepared using the 3D printing method and freeze-drying technology. Experiments and theoretical model analysis demonstrated that the taper and distribution of microchannels in the sponge affected the water and blood absorption properties, as well as the expansion ability. In treatment of SD rat liver defect and SD rat liver perforation wound, GS-1 sponge with the taper (1/15) microchannels exhibited an excellent hemostatic effect with blood loss of 0.866 ± 0.093 g and a hemostasis time of 280 ± 10 s. Results showed that the hemostatic capacities of GelMA sponges were increased with the bottom diameter (taper) of conical microchannels. This is a potential strategy to develop designed taper sponges with designed taper microchannels for rapidly controlling hemorrhage.

Polyvinyl alcohol/sodium alginate composite sponge with 3D ordered/disordered porous structure for rapidly controlling noncompressible hemorrhage.

It is still a challenge to develop a sponge that can efficiently control noncompressible bleeding to meet the emergency treatment and clinical demand. Herein, we combined the 3D printing sacrificial template method and freeze-drying technology to prepare polyvinyl alcohol/sodium alginate (PVA/SA) composite sponges with ordered microchannels and disordered porous structure. Compared with conventional sponges, the prepared sponge showed ultra-rapid water/blood absorption capacity and satisfactory mechanical properties. Furthermore, when the sponge was stuffed into a noncompressible wound and contacted with blood, it could accurately guide and quickly absorb a large amount of blood through the microchannels. Moreover, the platelets, red blood cells and coagulation factors would be enriched in the microchannels and microporous structure. In the SD rat liver noncompressible hemorrhage and femoral artery puncture injury model, PVA-SA composite sponge with 3D ordered/disordered porous structure showed enhanced hemostatic performance compared with commercial MPVA sponges. Depend on the special ordered/disordered porous structure, PVA-SA composite sponge could accelerate the blood convergence and promote coagulation. This design of special porous structure opened up a new avenue to develop hemostatic sponges for rapidly controlling noncompressible hemorrhage.

Design and synthesis of HDAC inhibitors to enhance the therapeutic effect of diffuse large B-cell lymphoma by improving metabolic stability and pharmacokinetic characteristics.

Histone deacetylases (HDAC) are clinically validated and attractive epigenetic drug targets for human cancers. Several HDAC inhibitors have been approved for cancer treatment to date, however, clinical applications have been limited due to the poor pharmacokinetics, bioavailability, selectivity of the HDAC inhibitors and most of them need to be combined with other drugs to achieve better results. Here, we describe our efforts toward the discovery of a novel series of lactam-based derivatives as selective HDAC inhibitors. Intensive structural modifications lead to the identification of compound 24g as the most active Class I HDAC Inhibitor, along with satisfactory metabolic stability in vitro (t1/2, human = 797 min) and the desirable oral bioavailability (F = 92%). More importantly, compound 24g showed good antitumor efficacy in a TMD-8 xenograft model (TGI = 77%) without obvious toxicity. These results indicated that Class I HDAC Inhibitor could be potentially used to treat certain diffuse large B-cell lymphoma therapeutics.

Human Cytomegalovirus Infection Activates Glioma Activating Transcription Factor 5 via microRNA in a Stress-Induced Manner.

Human cytomegalovirus (HCMV) harnesses a cell-specific manner to infect human nervous system cancer cells, establishes a life-long persistent infection without cell death, and modulates signaling pathways associated with cancer. We previously identified that the HCMV immediate-early 2 (IE2-86) protein binds and activates activating transcription factor 5 (ATF5), a survival factor in many tumor cells. In this study, we investigated a new mechanism of stress-induced miRNA regulation at the ATF5 3' UTR under the HCMV infection and other cellular stress conditions. We employed RNA-Seq and in silico analysis to screen stress response gene sets and identify miRNA candidates as potential regulators of ATF5 following HCMV infection. We found that ATF5 and cellular stress response genes were significantly upregulated under HCMV infection and diverse stress conditions. Three downregulated miRNAs were filtrated based on our threshold, and their binding sites for 3' UTR of ATF5 were predicted. Then, luciferase reporter assays were carried out to verify the binding sites for all three miRNA candidates targeting ATF5. However, in vitro validation has shown that miR-134-5p is the only candidate that can reverse the ATF5 protein upregulation under infection and other cell stresses. Additionally, miR-134-5p levels were significantly reduced and inversely related to ATF5 mRNA under HCMV infection. These results provide new evidence that quiescent HCMV infection can trigger a stress response in glioma cells and modulate ATF5 levels by downregulating specific miRNA.

Thrombin Embedded in eMPs@Thr/Sponge with Enhanced Procoagulant Ability for Uncompressible and Massive Hemorrhage Control.

Uncontrollable hemorrhage, especially uncompressible and massive hemorrhage, is life threatening. To develop a kind of hemostatic material that is biocompatible and has effective hemostatic performance, a starch-polyethylene glycol sponge (St-PEG sponge) incorporated with electrospraying microspheres made from carboxymethyl chitosan and sodium alginate (CMC/SA eMPs) is employed to fabricate the topical hemostatic agent for application. To load thrombin safely and effectively, CMC/SA eMPs encapsulating thrombin compounds (eMPs@Thr) are further incorporated with St-PEG sponge to obtain eMPs@Thr/sponge. The results show that eMPs@Thr/sponge could obviously reduce blood loss and shorten the hemostatis time compared with commercial hemostatic products Kuai Kang. The construction of the eMPs@Thr/sponge could not only maintain the expandable properties of the St-PEG sponge but also strengthen the procoagulant activity. Therefore, this work provides a facile approach for loading thrombin given the fact that thrombin suffers from instability and risk of thrombus. It is predicted that eMPs@Thr/sponge might hold great potential in uncompressible and massive hemorrhage control.

The PK/PD Interactions of Doxycycline against Mycoplasma gallisepticum.

Mycoplasma gallisepticum is one of the most important pathogens that cause chronic respiratory disease in chicken. This study investigated the antibacterial activity of doxycycline against M. gallisepticum strain S6. In static time-killing studies with constant antibiotic concentrations [0-64 minimum inhibitory concentration (MIC)], M. gallisepticum colonies were quantified and kill rates were calculated to estimate the drug effect. The half-life of doxycycline in chicken was 6.51 ± 0.63 h. An in vitro dynamic model (the drug concentrations are fluctuant) was also established and two half-lives of 6.51 and 12 h were simulated. The samples were collected for drug concentration determination and viable counting of M. gallisepticum. In static time-killing studies, doxycycline produced a maximum antimycoplasmal effect of 5.62log10 (CFU/mL) reduction and the maximum kill rate was 0.11 h(-1). In the in vitro dynamic model, doxycycline had a mycoplasmacidal activity in the two regimens, and the maximum antimycoplasmal effects were 4.1 and 4.75log10 (CFU/mL) reduction, respectively. Furthermore, the cumulative percentage of time over a 48-h period that the drug concentration exceeds the MIC (%T > MIC) was the pharmacokinetic-pharmacodynamic index that best correlated with antimicrobial efficacy (R (2) = 0.986, compared with 0.897 for the peak level divided by the MIC and 0.953 for the area under the concentration-time curve over 48 h divided by the MIC). The estimated %T > MIC values for 0log10 (CFU/mL) reduction, 2log10 (CFU/mL) reduction and 3log10 (CFU/mL) reduction were 32.48, 45.68, and 54.36%, respectively, during 48 h treatment period of doxycycline. In conclusion, doxycycline shows excellent effectiveness and time-dependent characteristics against M. gallisepticum strain S6 in vitro. Additionally, these results will guide optimal dosing strategies of doxycycline in M. gallisepticum infection.

In vivo evaluation of mutant selection window of cefquinome against Escherichia coli in piglet tissue-cage model.

BACKGROUND: The resistance of cephalosporins is significantly serious in veterinary clinic. In order to inhibit the bacterial resistance production, the mutant selection window (MSW) hypothesis with Escherichia coli (E. coli) ATCC 25922 exposed to cefquinome in an animal tissue-cage model was investigated. RESULTS: Localized infection with E. coli was established in piglets, and the infected animals were administrated intramuscularly with various doses and intervals of cefquinome to provide antibiotic concentrations below the MIC99, between the MIC99 and the mutant prevention concentration (MPC), and above the MPC. E. coli lost susceptibility when drug concentrations fluctuated between the lower and upper boundaries of the window, which defined in vitro as the MIC99 (0.06 µg/mL) and the MPC (0.16 µg/mL) respectively. For PK/PD parameters, there were no mutant selection enrichment when T>MIC99 was ≤ 25% or T>MPC was ≥ 50% of administration interval. When T>MIC99 was > 25% and T>MPC was <50% of administration interval, resistance selection was observed. When AUC24 h/MIC99 and AUC24 h/MPC were considered, the mutant selection window extended from 32.84 h to 125.64 h and from 12.83 h to 49.09 h, respectively. CONCLUSIONS: These findings demonstrate that the MSW exists in vivo for time-dependent antimicrobial agents, and its boundaries fit well with those determined in vitro. Maintenance of antimicrobial concentrations above the MPC for > 50% of administration interval is a straightforward way to restrict the acquisition of resistance in this tissue cage model. This situation was achieved with daily intramuscular doses of 1 mg cefquinome/kg body weight.

Tissue deposition and residue depletion of cyadox and its three major metabolites in pigs after oral administration.

Tissue deposition and residue depletion profiles of cyadox (Cyx) and its three major metabolites, including 1,4-bisdesoxycyadox (Cy1), 4-desoxycyadox (Cy2), and quinoxaline-2-carboxylic acid (QCA), in pigs after multiple oral administrations were determined. Thirty-five healthy adult pigs were randomly divided into seven groups and orally treated with Cyx at a dosage of 20 mg/kg of body weight for five consecutive days. Each group of five pigs was randomly slaughtered 12, 24, 72, 120, 168, 216, and 264 h after the last dosing, and tissue samples, including muscle, liver, kidney, and fat, were collected and analyzed via the liquid chromatography-tandem mass spectrometry method. The concentration-time data of Cyx and its three metabolites (Cy1, Cy2, and QCA) were analyzed with WinNonlin. Results showed that metabolites of Cyx were quickly generated in swine tissues and the concentrations of QCA in kidney were higher than those of Cyx and other metabolites in all edible tissues. These results provide further insight into the metabolism of Cyx and confirmation of the residue marker and target tissue of Cyx in pigs.