Functional analyses of Toxoplasma gondii dihydroorotase reveal a promising anti-parasitic target.

Toxoplasma gondii relies heavily on the de novo pyrimidine biosynthesis pathway for fueling the high uridine-5'-monophosphate (UMP) demand during parasite growth. The third step of de novo pyrimidine biosynthesis is catalyzed by dihydroorotase (DHO), a metalloenzyme that catalyzes the reversible condensation of carbamoyl aspartate to dihydroorotate. Here, functional analyses of TgDHO reveal that tachyzoites lacking DHO are impaired in overall growth due to decreased levels of UMP, and the noticeably growth restriction could be partially rescued after supplementation with uracil or high concentrations of L-dihydroorotate in vitro. When pyrimidine salvage pathway is disrupted, both DHOH35A and DHOD284E mutant strains proliferated much slower than DHO-expressing parasites, suggesting an essential role of both TgDHO His35 and Asp284 residues in parasite growth. Additionally, DHO deletion causes the limitation of bradyzoite growth under the condition of uracil supplementation or uracil deprivation. During the infection in mice, the DHO-deficient parasites are avirulent, despite the generation of smaller tissue cysts. The results reveal that TgDHO contributes to parasite growth both in vitro and in vivo. The significantly differences between TgDHO and mammalian DHO reflect that DHO can be exploited to produce specific inhibitors targeting apicomplexan parasites. Moreover, potential DHO inhibitors exert beneficial effects on enzymatic activity of TgDHO and T. gondii growth in vitro. In conclusion, these data highlight the important role of TgDHO in parasite growth and reveal that it is a promising anti-parasitic target for future control of toxoplasmosis.

Electron delocalization triggers nonradical Fenton-like catalysis over spinel oxides.

Nonradical Fenton-like catalysis offers opportunities to overcome the low efficiency and secondary pollution limitations of existing advanced oxidation decontamination technologies, but realizing this on transition metal spinel oxide catalysts remains challenging due to insufficient understanding of their catalytic mechanisms. Here, we explore the origins of catalytic selectivity of Fe-Mn spinel oxide and identify electron delocalization of the surface metal active site as the key driver of its nonradical catalysis. Through fine-tuning the crystal geometry to trigger Fe-Mn superexchange interaction at the spinel octahedra, ZnFeMnO4 with high-degree electron delocalization of the Mn-O unit was created to enable near 100% nonradical activation of peroxymonosulfate (PMS) at unprecedented utilization efficiency. The resulting surface-bound PMS* complex can efficiently oxidize electron-rich pollutants with extraordinary degradation activity, selectivity, and good environmental robustness to favor water decontamination applications. Our work provides a molecule-level understanding of the catalytic selectivity and bimetallic interactions of Fe-Mn spinel oxides, which may guide the design of low-cost spinel oxides for more selective and efficient decontamination applications.

Bactericidal and sterilizing activity of novel regimens combining bedaquiline or TBAJ-587 with GSK2556286 and TBA-7371 in a mouse model of tuberculosis.

The combination of bedaquiline, pretomanid, and linezolid (BPaL) has become a preferred regimen for treating multidrug- and extensively drug-resistant tuberculosis (TB). However, treatment-limiting toxicities of linezolid and reports of emerging bedaquiline and pretomanid resistance necessitate efforts to develop new short-course oral regimens. We recently found that the addition of GSK2556286 increases the bactericidal and sterilizing activity of BPa-containing regimens in a well-established BALB/c mouse model of tuberculosis. Here, we used this model to evaluate the potential of new regimens combining bedaquiline or the more potent diarylquinoline TBAJ-587 with GSK2556286 and the DprE1 inhibitor TBA-7371, all of which are currently in early-phase clinical trials. We found the combination of bedaquiline, GSK2556286, and TBA-7371 to be more active than the first-line regimen and nearly as effective as BPaL in terms of bactericidal and sterilizing activity. In addition, we found that GSK2556286 and TBA-7371 were as effective as pretomanid and the novel oxazolidinone TBI-223 when either drug pair was combined with TBAJ-587 and that the addition of GSK2556286 increased the bactericidal activity of the TBAJ-587, pretomanid, and TBI-223 combination. We conclude that GSK2556286 and TBA-7371 have the potential to replace pretomanid, an oxazolidinone, or both components, in combination with bedaquiline or TBAJ-587.

Profiling DNA Cargos in Single Extracellular Vesicles via Hydrogel-Based Droplet Digital Multiple Displacement Amplification.

Due to the substantial heterogeneity among extracellular vesicle (EV) subpopulations, single-EV analysis has the potential to elucidate the mechanisms behind EV biogenesis and shed light on the myriad functions, leading to the development of novel diagnostics and therapeutics. While many studies have been devoted to reveal between-EV variations in surface proteins and RNAs, DNA cargos (EV-DNA) have received little attention. Here, we report a hydrogel-based droplet digital multiple displacement amplification approach for the comprehensive analysis of EV-DNA at the single-EV level. Single EVs are dispersed in thousands of hydrogel droplets and lysed for DNA amplification and identification. The droplet microfluidics strategy empowers the assay with single-molecule sensitivity and capability for absolute quantification of DNA-containing EVs. In particular, our findings indicate that 5-40% EVs are associated with DNA, depending on the cell of origin. Large EVs exhibit a higher proportion of DNA-containing EVs and a more substantial presence of intraluminal DNA, compared to small EVs. These DNA-containing EVs carry multiple DNA fragments on average. Furthermore, both double-stranded DNA and single-stranded DNA were able to be detected at the single-EV level. Utilizing this method, the abundance, distribution, and biophysical properties of EV-DNA in various EV populations are evaluated. The DNA level within EVs provides insight into the status of the originating cells and offers valuable information on the outcomes of anticancer treatments. The utilization of single-EV analysis for EV-DNA holds significant promise for early cancer detection and treatment response monitoring.

Apolipoprotein A-IV polymorphisms Q360H and T347S attenuate its endogenous inhibition of thrombosis.

Platelets are small anucleate cells that play a key role in thrombosis and hemostasis. Our group previously identified apolipoprotein A-IV (apoA-IV) as an endogenous inhibitor of thrombosis by competitive blockade of the αIIbß3 integrin on platelets. ApoA-IV inhibition of platelets was dependent on the N-terminal D5/D13 residues, and enhanced with absence of the C-terminus, suggesting it sterically hinders its N-terminal platelet binding site. The C-terminus is also the site of common apoA-IV polymorphisms apoA-IV-1a (T347S) and apoA-IV-2 (Q360H). Interestingly, both are linked with an increased risk of cardiovascular disease, however, the underlying mechanism remains unclear. Here, we generated recombinant apoA-IV and found that the Q360H or T347S polymorphisms dampened its inhibition of platelet aggregation in human platelet-rich plasma and gel-filtered platelets, reduced its inhibition of platelet spreading, and its inhibition of P-selectin on activated platelets. Using an ex vivo thrombosis assay, we found that Q360H and T347S attenuated its inhibition of thrombosis at both high (1800s-1) and low (300s-1) shear rates. We then demonstrate a conserved monomer-dimer distribution among apoA-IV WT, Q360H, and T347S and use protein structure modelling software to show Q360H and T347S enhance C-terminal steric hindrance over the N-terminal platelet-binding site. These data provide critical insight into increased cardiovascular risk for individuals with Q360H or T347S polymorphisms.

The efficacy and safety of adding PD-1 blockade to induction chemotherapy and concurrent chemoradiotherapy (IC-CCRT) for locoregionally advanced nasopharyngeal carcinoma: an observational, propensity score-matched analysis.

BACKGROUND: Despite the success of PD-1 blockade in recurrent/metastatic nasopharyngeal carcinoma (NPC), its effect for locoregionally advanced NPC (LANPC) remains unclear. This study aimed to evaluate the benefit of adding PD-1 blockade to the current standard treatment (gemcitabine and cisplatin IC  plus cisplatin CCRT ) for LANPC patients. METHODS: From January 2020 to November 2022, 347 patients with non-metastatic high-risk LANPC (stage III-IVA, excluding T3-4N0) were included. Of the 347 patients, 268 patients were treated with standard treatment (IC-CCRT), and 79 received PD-1 blockade plus IC-CCRT (PD-1 group). For the PD-1 group, PD-1 blockade was given intravenously once every 3 weeks for up to 9 cycles (3 induction and 6 adjuvant). The primary endpoint was disease-free survival (DFS) (i.e. freedom from local/regional/distant failure or death). The propensity score matching (PSM) with the ratio of 1:2 was performed to control confounding factors. RESULTS: After PSM analysis, 150 patients receiving standard treatment and 75 patients receiving additional PD-1 blockade remained in the current analysis. After three cycles of IC, the PD-1 group had significantly higher rates of complete response (defined as disappearance of all target lesions; 24% vs. 9%; P = 0.006) and complete biological response (defined as undetectable cell-free Epstein-Barr virus DNA, cfEBV DNA; 79% vs. 65%; P = 0.046) than that in the standard group. And the incidence of grade 3-4 toxicity during IC was 47% in the PD-1 group and 41% in the standard group, with no significant difference (P = 0.396). During follow-up period, additional PD-1 blockade to standard treatment improved 3-year DFS from 84 to 95%, with marginal statistical significance (HR, 0.28; 95%CI, 0.06-1.19; P = 0.064). CONCLUSION: Additiaonl PD-1 blockade to gemcitabine and cisplatin IC and adjuvant treatment results in significant improvement in tumor regression, cfEBV DNA clearance, superior DFS, and comparable toxicity profiles in high-risk LANPC patients.

Elastic SiC Aerogel for Thermal Insulation: A Systematic Review.

SiC aerogels with their lightweight nature and exceptional thermal insulation properties have emerged as the most ideal materials for thermal protection in hypersonic vehicles; However, conventional SiC aerogels are prone to brittleness and mechanical degradation when exposed to complex loads such as shock and mechanical vibration. Hence, preserving the structural integrity of aerogels under the combined influence of thermal and mechanical external forces is crucial not only for stabling their thermal insulation performance but also for determining their practicality in harsh environments. This review focuses on the optimization of design based on the structure-performance of SiC aerogels, providing a comprehensive review of the inherent correlations among structural stability, mechanical properties, and insulation performance. First, the thermal transfer mechanism of aerogels from a microstructural perspective is studied, followed by the relationship between the building blocks of SiC aerogels (0D particles, 1D nanowires/nanofibers) and their compression performance (including compressive resilience, compressive strength, and fatigue resistance). Moreover, the strategy to improve the high-temperature oxidation resistance and insulation performance of SiC aerogels is explored. Lastly, the challenges and future breakthrough directions for SiC aerogels are presented.

Phase-Tailoring Wx V1-x O2 Meta-Nanofiber Enables Temperature-Editing Energy Control.

Room-temperature phase change materials (RTPCMs) exhibit promise to address challenges in thermal energy storage and release, greatly aiding in numerous domains of human existence and productivity. The conventional RTPCMs undergo inevitable volume expansion, structural collapse, and diffusion of active ingredients while maintaining desirable phase change enthalpy and ideal phase change temperature. Here, a sol-gel 1D-induced growth approach is presented to fabricate meta nanofibers (Meta-NFs) comprised of vanadium dioxide with monoclinic crystal structure, and further achieve the editable phase change temperature from 68 to 37 °C through W-doping, which allowed for tailored length variation of the zigzag V-V bond. Subsequently, Meta-NFs are assembled into 3D aerogels with self-standing architecture, thereby enabling the independent use of the RTPCMs. The obtained metamaterials demonstrate not only the temperature-editing solid-solid phase transition, but also the stiffness of the ceramic matrix, exhibiting the thermal energy control capability at room temperature (37 °C), thermal insulation properties, temperature resistance, and flame retardancy. The effective creation of these fascinating metamaterials might offer new insights for next-generation and self-standing solid-solid RTPCMs.

Operando Spectroscopy Observation of Mo Clusters-Ti3 C2 TX Catalyst/Support Interface's Dynamic Evolution in Hydrogen Evolution Reaction.

The interaction between catalyst and support plays an important role in electrocatalytic hydrogen evolution (HER), which may explain the improvement in performance by phase transition or structural remodeling. However, the intrinsic behavior of these catalysts (dynamic evolution of the interface under bias, structural/morphological transformation, stability) has not been clearly monitored, while the operando technology does well in capturing the dynamic changes in the reaction process in real time to determine the actual active site. In this paper, nitrogen-doped molybdenum atom-clusters on Ti3 C2 TX (MoACs /N-Ti3 C2 TX ) is used as a model catalyst to reveal the dynamic evolution of MoAcs on Ti3 C2 TX during the HER process. Operando X-ray absorption structure (XAS) theoretical calculation and in situ Raman spectroscopy showed that the Mo cluster structure evolves to a 6-coordinated monatomic Mo structure under working conditions, exposing more active sites and thus improving the catalytic performance. It shows excellent HER performance comparable to that of commercial Pt/C, including an overpotential of 60 mV at 10 mA cm-2 , a small Tafel slope (56 mV dec-1 ), and high activity and durability. This study provides a unique perspective for investigating the evolution of species, interfacial migration mechanisms, and sources of activity-enhancing compounds in the process of electroreduction.

Mogroside V reduced the excessive endoplasmic reticulum stress and mitigated the Ulcerative colitis induced by dextran sulfate sodium in mice.

Ulcerative colitis (UC) is an idiopathic, chronic inflammatory condition of the colon, characterized by repeated attacks, a lack of effective treatment options, and significant physical and mental health complications for patients. The endoplasmic reticulum (ER) is a vital intracellular organelle in maintaining cellular homeostasis. Endoplasmic reticulum stress (ERS) is induced when the body is exposed to adverse external stimuli. Numerous studies have shown that ERS-induced apoptosis plays a vital role in the pathogenesis of UC. Mogroside V (MV), an active ingredient of Monk fruit, has demonstrated excellent anti-inflammatory and antioxidant effects. In this study, we investigated the therapeutic effects of MV on dextran sulfate sodium (DSS)-induced UC and its potential mechanisms based on ERS. The results showed that MV exerted a protective effect against DSS-induced UC in mice as reflected by reduced DAI scores, increased colon length, reduced histological scores of the colon, and levels of pro-inflammatory cytokines, as well as decreased intestinal permeability. In addition, the expression of ERS pathway including BIP, PERK, eIF2α, ATF4, CHOP, as well as the apoptosis-related protein including Caspase-12, Bcl-2 and Bax, was found to be elevated in UC. However, MV treatment significantly inhibited the UC and reversed the expression of inflammation signaling pathway including ERS and ERS-induced apoptosis. Additionally, the addition of tunicamycin (Tm), an ERS activator, significantly weakened the therapeutic effect of MV on UC in mice. These findings suggest that MV may be a therapeutic agent for the treatment of DSS-induced UC by inhibiting the activation of the ERS-apoptosis pathway, and may provide a novel avenue for the treatment of UC.

The role of endoplasmic reticulum stress in regulation of intestinal barrier and inflammatory bowel disease.

Inflammatory bowel disease (IBD) is a chronic inflammatory disease involving the digestive tract, characterized by abdominal pain, diarrhea, rectal bleeding, and so on, which can make patients physically weakened and live difficultly. Although IBD has been recognized for many years, the pathogenesis of IBD has not yet been established and damage to intestinal barrier is thought to be closely associated with IBD. Intestinal barrier is an innate barrier that maintains the homeostasis of the intestinal environment and impedes pathogenic bacteria and toxins, and the endoplasmic reticulum (ER) has recently been found to be involved in maintaining the integrity of intestinal barrier. Endoplasmic reticulum stress (ERS) is a status of endoplasmic reticulum damaged when unfolded or misfolded proteins accumulate in excess of the degradation systematic clearance limit of the misfolded proteins. The regulation of ERS on protein folding synthesis and maintenance of cellular homeostasis is an important factor in influencing the integrity of the intestinal barrier. This paper mainly discusses the relationship between ERS and the intestinal barrier, aiming to understand the regulatory role of ERS on the intestinal barrier and the mechanism and to improve new solutions and notions for the treatment or prevention of IBD.

Cold exposure-induced plasma exosomes impair bone mass by inhibiting autophagy.

Recently, environmental temperature has been shown to regulate bone homeostasis. However, the mechanisms by which cold exposure affects bone mass remain unclear. In our present study, we observed that exposure to cold temperature (CT) decreased bone mass and quality in mice. Furthermore, a transplant of exosomes derived from the plasma of mice exposed to cold temperature (CT-EXO) can also impair the osteogenic differentiation of BMSCs and decrease bone mass by inhibiting autophagic activity. Rapamycin, a potent inducer of autophagy, can reverse cold exposure or CT-EXO-induced bone loss. Microarray sequencing revealed that cold exposure increases the miR-25-3p level in CT-EXO. Mechanistic studies showed that miR-25-3p can inhibit the osteogenic differentiation and autophagic activity of BMSCs. It is shown that inhibition of exosomes release or downregulation of miR-25-3p level can suppress CT-induced bone loss. This study identifies that CT-EXO mediates CT-induced osteoporotic effects through miR-25-3p by inhibiting autophagy via targeting SATB2, presenting a novel mechanism underlying the effect of cold temperature on bone mass.

Diterpenoid Alkaloids from Delphinium liangshanense.

Two new C19-diterpenoid alkaloids of the lycoctonine-type (liangshanine A and liangshanine B) and nineteen known compounds (3-21) were isolated from the whole plant of Delphinium liangshanense W. T. Wang, and all the compounds were identified by different spectroscopic analyses, such as IR, HR-ESI-MS and NMR. All the compounds were isolated from this plant for the first time and tested for the anti-proliferation effects on MH7 A and SF9 cells to figure their anti-rheumatoid arthritis and anti-insect activity, but none of them showed remarkable activity.

Phase-Engineered VO2 Metal Nanofiber Enables a Metal-Insulator Transition for Bidirectional Thermal Reallocation.

Phase change materials (PCMs) are appealing for their fascinating capability of thermal reallocation, assisting widely in many areas of human productivity and life. However, it has remained a significant challenge to attain shape stability, temperature resistance, and microscale continuity in PCMs while maintaining sufficient phase change performance. Here we report a sol epitaxial fabrication strategy to create metal-insulator transition nanofibers (MIT-NFs) composed of monoclinic vanadium dioxide. The MIT-NFs are further assembled into self-standing two-dimensional membranes and three-dimensional aerogels with structural robustness. The resulting series of metal-insulator transition materials exhibits the integrated features of solid-solid phase change properties, shape stability, and thermal reallocation properties. The integral ceramic characteristic also provides the MIT-NFs with surface stiffness (54 GPa), temperature resistance (-196° to 330 °C), and thermal insulator properties. The successful fabrication of these captivating MIT materials may provide new perspectives for next-generation, shape-stable, and self-standing PCMs.

Calculating a Prefecture-Level Well-Being Index in Japan: Applying the framework of the OECD's Better Life Index.

Objectives　Well-being serves as a crucial indicator of national governance and societal advancement. Consequently, the Better Life Index (BLI) developed by the Organisation for Economic Co-operation and Development (OECD) has emerged as a pivotal multidimensional measure of well-being, surpassing traditional indicators such as Gross Domestic Product (GDP). However, current well-being indicators predominantly focus on national measurements and do not effectively evaluate well-being in smaller regions such as states or prefectures. This study aimed to calculate a Regional Well-Being Index (RWI) tailored to localized areas in Japan.Methods　Japanese official statistics, publicly available as open data, were analyzed, focusing on 11 domains similar to those in the BLI: "Income," "Jobs," "Housing," "Health," "Work-Life Balance," "Education," "Community," "Civic Engagement," "Environment," "Safety," and "Life Satisfaction." The RWI scores were calculated for each prefecture in 2010, 2013, 2016, and 2019 using standard normalization techniques. To represent the overall well-being of each prefecture in each year, scores were aggregated across all domains; this aggregate is referred to as the Integrated RWI. The reliability and validity of RWI were assessed by examining time-series changes and Pearson's correlation coefficients.Results　Median Integrated RWI scores for Japanese prefectures remained relatively stable across the study period, with slight variations observed: median = 0.67 (Interquartile range [IQR]: -2.48-2.71) in 2010, median = 0.00 (IQR: -2.85-2.76) in 2013, median = 0.13 (IQR: -3.05-2.49) in 2016, and median = 0.19 (IQR: -2.75-3.06) in 2019. Geographical analysis showed lower scores in regions such as Western Kyushu and Shikoku, and higher scores in Chubu and Eastern Kinki. The RWI and the BLI demonstrated construct validity, with Pearson's correlation coefficients ranging from 0.58 to 0.99 across various domains.Conclusion　The RWI, based on the OECD's BLI, proved to be a reliable and valid tool for assessing comprehensive well-being at the regional level in Japan. It offers foundational data for identifying challenges to regional well-being and shaping targeted policies, thereby contributing to evidence-based policymaking. Moreover, this methodology has potential applicability in evaluating comprehensive well-being beyond GDP at the regional level in other countries using official statistics.

[Determination of nine components of fried Ziziphi Spinosae Semen extract in beagle dog plasma by UPLC-MS/MS and its application in pharmacokinetic research].

This study established a convenient, rapid, and sensitive ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS) method for simultaneous determination of magnoflorine,(R)-coclaurine, vicenin Ⅱ, isospinosin, spinosin, swertisin, N-nornuciferine, 6-feruloylspinosin, and jujuboside B in beagle dog plasma after oral administration of fried Ziziphi Spinosae Semen(FZSS) extract. The Waters HSS-T3 C_(18) column(2.1 mm×100 mm, 1.8 µm) was used. The methanol-aqueous solution(containing 0.01% formic acid) was adopted as the mobile phase for gradient elution. The nine components and two internal standards were completely separated within 8 min. The mass spectrometry detection was performed in multiple reaction monitoring(MRM) mode by positive and negative ion switching of electrospray ionization. The analytical method was validated in terms of specificity, selectivity, linear range, accuracy, precision, recovery, matrix effect, and stability. It could meet the requirement of pharmacokinetic research after oral administration of FZSS extract to beagle dogs. The results showed that the time to reach the peak concentration(T_(max)) of magnoflorine,(R)-coclaurine, vicenin Ⅱ, isospinosin, spinosin, 6-feruloylspinosin, and jujuboside B was 2.40-3.20 h, and the elimination halflife(t_(1/2)) was 2.08-6.79 h after a single-dose oral administration of FZSS to beagle dogs. The exposure of magnoflorine and spinosin was high, with a peak concentration(C_(max)) of 76.7 and 31.5 ng·mL~(-1) and an area under the curve(AUC_(0-∞)) of 581 and 315 ng·h·mL~(-1), respectively. The exposure of the remaining five compounds was lower, with a C_(max) of 0.81-13.0 ng·mL~(-1) and an AUC_(0-∞) of 6.00-106 ng·h·mL~(-1). This study provides a reference for the follow-up research of FZSS.

Contezolid can replace linezolid in a novel combination with bedaquiline and pretomanid in a murine model of tuberculosis.

Contezolid is a new oxazolidinone with in vitro and in vivo activity against Mycobacterium tuberculosis comparable to that of linezolid. Pre-clinical and clinical safety studies suggest it may be less toxic than linezolid, making contezolid a potential candidate to replace linezolid in the treatment of drug-resistant tuberculosis. We evaluated the dose-ranging activity of contezolid, alone and in combination with bedaquiline and pretomanid, and compared it with linezolid at similar doses, in an established BALB/c mouse model of tuberculosis. Contezolid had an MIC of 1 µg/mL, similar to linezolid, and exhibited similar bactericidal activity in mice. Contezolid-resistant mutants selected in vitro had 32- to 64-fold increases in contezolid MIC and harbored mutations in the mce3R gene. These mutants did not display cross-resistance to linezolid. Our results indicate that contezolid has the potential to replace linezolid in regimens containing bedaquiline and pretomanid and likely other regimens.

Using Dynamic Oral Dosing of Rifapentine and Rifabutin to Simulate Exposure Profiles of Long-Acting Formulations in a Mouse Model of Tuberculosis Preventive Therapy.

Administration of tuberculosis preventive therapy (TPT) to individuals with latent tuberculosis infection is an important facet of global tuberculosis control. The use of long-acting injectable (LAI) drug formulations may simplify and shorten regimens for this indication. Rifapentine and rifabutin have antituberculosis activity and physiochemical properties suitable for LAI formulation, but there are limited data available for determining the target exposure profiles required for efficacy in TPT regimens. The objective of this study was to determine exposure-activity profiles of rifapentine and rifabutin to inform development of LAI formulations for TPT. We used a validated paucibacillary mouse model of TPT in combination with dynamic oral dosing of both drugs to simulate and understand exposure-activity relationships to inform posology for future LAI formulations. This work identified several LAI-like exposure profiles of rifapentine and rifabutin that, if achieved by LAI formulations, could be efficacious as TPT regimens and thus can serve as experimentally determined targets for novel LAI formulations of these drugs. We present novel methodology to understand the exposure-response relationship and inform the value proposition for investment in development of LAI formulations that have utility beyond latent tuberculosis infection.

Next-Generation Diarylquinolines Improve Sterilizing Activity of Regimens with Pretomanid and the Novel Oxazolidinone TBI-223 in a Mouse Tuberculosis Model.

A regimen comprised of bedaquiline (BDQ, or B), pretomanid, and linezolid (BPaL) is the first oral 6-month regimen approved by the U.S. Food and Drug Administration and recommended by the World Health Organization for the treatment of extensively drug-resistant tuberculosis. We used a well-established BALB/c mouse model of tuberculosis to evaluate the treatment-shortening potential of replacing bedaquiline with either of two new, more potent diarylquinolines, TBAJ-587 and TBAJ-876, in early clinical trials. We also evaluated the effect of replacing linezolid with a new oxazolidinone, TBI-223, exhibiting a larger safety margin with respect to mitochondrial toxicity in preclinical studies. Replacing bedaquiline with TBAJ-587 at the same 25-mg/kg dose significantly reduced the proportion of mice relapsing after 2 months of treatment, while replacing linezolid with TBI-223 at the same 100-mg/kg dose did not significantly change the proportion of mice relapsing. Replacing linezolid or TBI-223 with sutezolid in combination with TBAJ-587 and pretomanid significantly reduced the proportion of mice relapsing. In combination with pretomanid and TBI-223, TBAJ-876 at 6.25 mg/kg was equipotent to TBAJ-587 at 25 mg/kg. We conclude that replacement of bedaquiline with these more efficacious and potentially safer diarylquinolines and replacement of linezolid with potentially safer and at least as efficacious oxazolidinones in the clinically successful BPaL regimen may lead to superior regimens capable of treating both drug-susceptible and drug-resistant TB more effectively and safely.

On-Site-Activated Transmembrane Logic DNA Nanodevice Enables Highly Specific Imaging of Cancer Cells by Targeting Tumor-Related Nucleolin and Intracellular MicroRNA.

The ability to specifically image cancer cells is essential for cancer diagnosis; however, this ability is limited by the false positive associated with single-biomarker sensors and off-site activation of "always active" nucleic acid probes. Herein, we propose an on-site, activatable, transmembrane logic DNA (TLD) nanodevice that enables dual-biomarker sensing of tumor-related nucleolin and intracellular microRNA for highly specific cancer cell imaging. The TLD nanodevice is constructed by assembling a tetrahedral DNA nanostructure containing a linker (L)-blocker (B)-DNAzyme (D)-substrate (S) unit. AS-apt, a DNA strand containing an elongated segment and the AS1411 aptamer, is pre-anchored to nucleolin protein, which is specifically expressed on the membrane of cancer cells. Initially, the TLD nanodevice is firmly sealed by the blocker containing an AS-apt recognition zone, which prevents off-site activation. When the nanodevice encounters a target cancer cell, AS-apt (input 1) binds to the blocker and unlocks the sensing ability of the nanodevice for miR-21 (input 2). The TLD nanodevice achieves dual-biomarker sensing from the cell membrane to the cytoplasm, thereby ensuring cancer cell-specific imaging. This TLD nanodevice represents a promising strategy for the highly reliable analysis of intracellular biomarkers and a promising platform for cancer diagnosis and related biomedical applications.