A Structural Change in Butyrophilin upon Phosphoantigen Binding Underlies Phosphoantigen-Mediated Vγ9Vδ2 T Cell Activation.

Human Vγ9Vδ2 T cells respond to microbial infections and malignancy by sensing diphosphate-containing metabolites called phosphoantigens, which bind to the intracellular domain of butyrophilin 3A1, triggering extracellular interactions with the Vγ9Vδ2 T cell receptor (TCR). Here, we examined the molecular basis of this "inside-out" triggering mechanism. Crystal structures of intracellular butyrophilin 3A proteins alone or in complex with the potent microbial phosphoantigen HMBPP or a synthetic analog revealed key features of phosphoantigens and butyrophilins required for γδ T cell activation. Analyses with chemical probes and molecular dynamic simulations demonstrated that dimerized intracellular proteins cooperate in sensing HMBPP to enhance the efficiency of γδ T cell activation. HMBPP binding to butyrophilin doubled the binding force between a γδ T cell and a target cell during "outside" signaling, as measured by single-cell force microscopy. Our findings provide insight into the "inside-out" triggering of Vγ9Vδ2 T cell activation by phosphoantigen-bound butyrophilin, facilitating immunotherapeutic drug design.

Embryonic stem cell related gene regulates alternative splicing of transcription factor 3 to maintain human embryonic stem cells' self-renewal and pluripotency.

Exploring the mechanism of self-renewal and pluripotency maintenance of human embryonic stem cells (hESCs) is of great significance in basic research and clinical applications, but it has not been fully elucidated. Long non-coding RNAs (lncRNAs) have been shown to play a key role in the self-renewal and pluripotency maintenance of hESCs. We previously reported that the lncRNA ESRG, which is highly expressed in undifferentiated hESCs, can maintain the self-renewal and pluripotency of hPSCs. RNA pull-down mass spectrometry showed that ESRG could bind to other proteins, among which heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) attracted our attention. In this study, we showed that HNRNPA1 can maintain self-renewal and pluripotency of hESCs. ESRG bound to and stabilized HNRNPA1 protein through the ubiquitin-proteasome pathway. In addition, knockdown of ESRG or HNRNPA1 resulted in alternative splicing of TCF3, which originally and primarily encoded E12, to mainly encode E47 and inhibit CDH1 expression. HNRNPA1 could rescue the biological function changes of hESCs caused by ESRG knockdown or overexpression. Our results suggest that ESRG regulates the alternative splicing of TCF3 to affect CDH1 expression and maintain hESCs self-renewal and pluripotency by binding and stabilizing HNRNPA1 protein. This study lays a good foundation for exploring the new molecular regulatory mechanism by which ESRG maintains hESCs self-renewal and pluripotency.

Deubiquitinase USP9X stabilizes RNA m6A demethylase ALKBH5 and promotes acute myeloid leukemia cell survival.

Post-translational modifications including protein ubiquitination regulate a plethora of cellular processes in distinct manners. RNA N6-methyladenosine is the most abundant post-transcriptional modification on mammalian mRNAs and plays important roles in various physiological and pathological conditions including hematologic malignancies. We previously determined that the RNA N6-methyladenosine eraser ALKBH5 is necessary for the maintenance of acute myeloid leukemia (AML) stem cell function, but the post-translational modifications involved in ALKBH5 regulation remain elusive. Here, we show that deubiquitinase ubiquitin-specific peptidase 9X (USP9X) stabilizes ALKBH5 and promotes AML cell survival. Through the use of mass spectrometry as an unbiased approach, we identify USP9X and confirm that it directly binds to ALKBH5. USP9X stabilizes ALKBH5 by removing the K48-linked polyubiquitin chain at K57. Using human myeloid leukemia cells and a murine AML model, we find that genetic knockdown or pharmaceutical inhibition of USP9X inhibits leukemia cell proliferation, induces apoptosis, and delays AML development. Ectopic expression of ALKBH5 partially mediates the function of USP9X in AML. Overall, this study uncovers deubiquitinase USP9X as a key for stabilizing ALKBH5 expression and reveals the important role of USP9X in AML, which provides a promising therapeutic strategy for AML treatment in the clinic.

A noninvasive multianalytical approach establishment for risk assessment and gastric cancer screening.

Effective screening and early detection are critical to improve the prognosis of gastric cancer (GC). Our study aims to explore noninvasive multianalytical biomarkers and construct integrative models for preliminary risk assessment and GC detection. Whole genomewide methylation marker discovery was conducted with CpG tandems target amplification (CTTA) in cfDNA from large asymptomatic screening participants in a high-risk area of GC. The methylation and mutation candidates were validated simultaneously using one plasma from patients at various gastric lesion stages by multiplex profiling with Mutation Capsule Plus (MCP). Helicobacter pylori specific antibodies were detected with a recomLine assay. Integrated models were constructed and validated by the combination of multianalytical biomarkers. A total of 146 and 120 novel methylation markers were found in CpG islands and promoter regions across the genome with CTTA. The methylation markers together with the candidate mutations were validated with MCP and used to establish a 133-methylation-marker panel for risk assessment of suspicious precancerous lesions and GC cases and a 49-methylation-marker panel as well as a 144-amplicon-mutation panel for GC detection. An integrated model comprising both methylation and specific antibody panels performed better for risk assessment than a traditional model (AUC, 0.83 and 0.63, P < .001). A second model for GC detection integrating methylation and mutation panels also outperformed the traditional model (AUC, 0.82 and 0.68, P = .005). Our study established methylation, mutation and H. pylori-specific antibody panels and constructed two integrated models for risk assessment and GC screening. Our findings provide new insights for a more precise GC screening strategy in the future.

ED50 of ciprofol combined with sufentanil for fiberoptic bronchoscopy of different patient populations with pulmonary tuberculosis.

BACKGROUND: Ciprofol is a promising sedative. This study aims to explore the median effective dose (ED50) of ciprofol in inhibiting responses to fiberoptic bronchoscopy in patients with pulmonary tuberculosis (PTB) of different genders and ages when combined with 0.15 µg/kg sufentanil, and to evaluate its efficacy and safety, providing a reference for the rational use of ciprofol in clinical practice. METHODS: PTB patients who underwent bronchoscopy examination and treatment at The Third People's Hospital of Changzhou between May 2023 and June 2023 were selected and divided into four groups using a stratified random method. All patients received intravenous injection of 0.15 µg/kg sufentanil followed by injection of the test dose of ciprofol according to Dixon's up-and-down method. The initial dose of ciprofol in all four groups was 0.4 mg/kg, with an adjacent ratio of 1:1.1. The next patient received a 10% increase in the dose of ciprofol if the previous patient in the same group experienced positive reactions such as choking cough, frowning, and body movements during the endoscopy. Otherwise, it was judged as a negative reaction, and the next patient received a 10% decrease in the dose of ciprofol. The transition from a positive reaction to a negative reaction was defined as a turning point, and the study of the group was terminated when seven turning points occurred. Hemodynamic parameters, oxygen saturation and adverse reactions were recorded at different time points in all groups. The Probit regression analysis method was used to calculate the ED50 of ciprofol in the four groups and compare between the groups. RESULTS: The ED50 of ciprofol combined with 0.15 µg/kg sufentanil for bronchoscopy in the four groups were 0.465 mg/kg, 0.433 mg/kg, 0.420 mg/kg and 0.396 mg/kg, respectively. CONCLUSION: The ED50 of ciprofol used for fiberoptic bronchoscopy varied among PTB patients of different genders and ages. TRIAL REGISTRATION: The Chinese Clinical Trial Registry, ChiCTR2300071508, Registered on 17 May 2023.

Exploring factors influencing delayed first antibiotic treatment for suspected early-onset sepsis in preterm newborns: a study before quality improvement initiative.

BACKGROUND: Early-onset sepsis (EOS) is a serious illness that affects preterm newborns, and delayed antibiotic initiation may increase the risk of adverse outcomes. PURPOSE: The objective of this study was to examine the present time of antibiotic administration in preterm infants with suspected EOS and the factors that contribute to delayed antibiotic initiation. METHODS: In this retrospective study in China, a total of 82 early preterm infants with suspected EOS between December 2021 and March 2023 were included. The study utilized a linear regression analytical approach to identify independent factors that contribute to delayed antibiotic administration. RESULTS: The mean gestational age and birth weight of the study population were 29.1 ± 1.4 weeks and 1265.7 ± 176.8 g, respectively. The median time of initial antibiotic administration was 3.8 (3.1-5.0) hours. Linear regression revealed that severe respiratory distress syndrome (RDS) (ß = 0.07, P = 0.013), penicillin skin test (PST) timing (ß = 0.06, P < 0.001) and medical order timing (ß = 0.04, P = 0.017) were significantly associated with the initial timing of antibiotic administration. CONCLUSIONS: There is an evident delay in antibiotic administration in preterm infants with suspected EOS in our unit. Severe RDS, PST postponement and delayed medical orders were found to be associated with the delayed use of antibiotics, which will be helpful for quality improvement efforts in the neonatal intensive care unit (NICU).

Advancements in Characterization Techniques for Microemulsions: From Molecular Insights to Macroscopic Phenomena.

Microemulsions are thermodynamically stable, optically isotropic, transparent, or semi-transparent mixed solutions composed of two immiscible solvents stabilized by amphiphilic solutes. This comprehensive review explores state-of-the-art techniques for characterizing microemulsions, which are versatile solutions essential across various industries, such as pharmaceuticals, food, and petroleum. This article delves into spectroscopic methods, nuclear magnetic resonance, small-angle scattering, dynamic light scattering, conductometry, zeta potential analysis, cryo-electron microscopy, refractive index measurement, and differential scanning calorimetry, examining each technique's strengths, limitations, and potential applications. Emphasizing the necessity of a multi-technique approach for a thorough understanding, it underscores the importance of integrating diverse analytical methods to unravel microemulsion structures from molecular to macroscopic scales. This synthesis provides a roadmap for researchers and practitioners, fostering advancements in microemulsion science and its wide-ranging industrial applications.

YBX1 is required for maintaining myeloid leukemia cell survival by regulating BCL2 stability in an m6A-dependent manner.

RNA-binding proteins (RBPs) are critical regulators of transcription and translation that are often dysregulated in cancer. Although RBPs are increasingly recognized as being important for normal hematopoiesis and for hematologic malignancies as oncogenes or tumor suppressors, RBPs that are essential for the maintenance and survival of leukemia remain elusive. Here we show that YBX1 is specifically required for maintaining myeloid leukemia cell survival in an N6-methyladenosine (m6A)-dependent manner. We found that expression of YBX1 is significantly upregulated in myeloid leukemia cells, and deletion of YBX1 dramatically induces apoptosis and promotes differentiation coupled with reduced proliferation and impaired leukemic capacity of primary human and mouse acute myeloid leukemia cells in vitro and in vivo. Loss of YBX1 has no obvious effect on normal hematopoiesis. Mechanistically, YBX1 interacts with insulin-like growth factor 2 messenger RNA (mRNA)-binding proteins (IGF2BPs) and stabilizes m6A-tagged RNA. Moreover, YBX1 deficiency dysregulates the expression of apoptosis-related genes and promotes mRNA decay of MYC and BCL2 in an m6A-dependent manner, which contributes to the defective survival that results from deletion of YBX1. Thus, our findings have uncovered a selective and critical role of YBX1 in maintaining myeloid leukemia survival, which might provide a rationale for the therapeutic targeting of YBX1 in myeloid leukemia.

Pax transactivation domain-interacting protein is required for preserving hematopoietic stem cell quiescence via regulating lysosomal activity.

Hematopoietic stem cells (HSC) maintain lifetime whole blood hematopoiesis through self-renewal and differentiation. In order to sustain HSC stemness, most HSC reside in a quiescence state, which is affected by diverse cellular stress and intracellular signal transduction. How HSC accommodate those challenges to preserve lifetime capacity remains elusive. Here we show that Pax transactivation domain-interacting protein (PTIP) is required for preserving HSC quiescence via regulating lysosomal activity. Using a genetic knockout mouse model to specifically delete Ptip in HSC, we find that loss of Ptip promotes HSC exiting quiescence, and results in functional exhaustion of HSC. Mechanistically, Ptip loss increases lysosomal degradative activity of HSC. Restraining lysosomal activity restores the quiescence and repopulation potency of Ptip-/- HSC. Additionally, PTIP interacts with SMAD2/3 and mediates transforming growth factor-ß signaling-induced HSC quiescence. Overall, our work uncovers a key role of PTIP in sustaining HSC quiescence via regulating lysosomal activity.

HLA-DQ genotype distribution and risk evaluation of celiac disease in Northwest China.

BACKGROUND: Celiac disease (CD) is an autoimmune small bowel disease. Genetic susceptibility for CD is mainly determined by the human leukocyte antigen (HLA)-DQ haplotypes. The risk of CD conferred by HLA genotypes varies geographically and across populations, however, this has not yet been documented in Chinese patients with CD. AIMS: To investigate the distribution of HLA-DQ and the related risks of CD development in Northwest China. METHODS: A total of 75 CD patients and 300 healthy individuals were genotyped for HLA-DQ using the Illumina NextSeq, and the relative risks of the different genotypes were evaluated. RESULTS: In total, 68.00% of CD patients and 21.00% of controls carried HLA-DQ2.5 heterodimers (p < 0.001). We identified four CD risk gradients. Individuals carrying a double dose of DQB1*02 had the highest risk of developing CD (1:16); however, with heterozygosis (DQB1*02:02/DQB1*02:01) having the highest risk (1:9). HLA-DQ2.5 individuals with a single copy of HLA-DQB1*02, in either the cis or trans configuration, were at a medium risk (1:38). Non-DQ2.5 carriers of DQ8 or DQ2.2 were at low risk, while only carriers of DQ7.5 or DQX.5 were at very low risk. Patients with the HLA-DQ2.5 genotype had more severe mucosal damage compared with the HLA-DQ2.5 genotype negative CD patients (70.59% vs. 41.67%, p = 0.016). CONCLUSION: Genetic susceptibility to CD is highly prevalent in the Northwest Chinese population and the highest risk of developing CD was associated with the DQ2.5/DQ2.2 genotype. The DQ2.5 allele is involved in the severity of mucosal injury.

Photocatalytic synthesis of azaheterocycle-fused piperidines and pyrrolidines via tandem difunctionalization of unactivated alkenes.

A variety of azaheterocycle-fused piperidines and pyrrolidines bearing CF3 and CHF2 functionalities were obtained using CF3SO2Na and CHF2SO2Na by visible light photocatalysis. This protocol involves a radical cascade cyclization via tandem tri- and difluoromethylation-arylation of pendent unactivated alkenes. Benzimidazole, imidazole, theophylline, purine, and indole serve as applicable anchors, thereby enriching the structural diversity of piperidine and pyrrolidine derivatives. This method features mild, additive-free and transition metal-free conditions.

Mitochondrial pyruvate carrier influences ganoderic acid biosynthesis in Ganoderma lucidum.

Mitochondrial pyruvate carriers (MPCs), located in the inner membrane of mitochondria, are essential carriers for pyruvate to enter mitochondria. MPCs regulate a wide range of intracellular metabolic processes, such as glycolysis, the tricarboxylic acid cycle (TCA cycle), fatty acid metabolism, and amino acid metabolism. However, the metabolic regulation of MPCs in macrofungi is poorly studied. We studied the role of MPCs in Ganoderma lucidum (GlMPC) on ganoderic acid (GA) biosynthesis regulation in G. lucidum. In this study, we found that the mitochondrial/cytoplasmic ratio of pyruvate was downregulated about 75% in GlMPC1- and GlMPC2-silenced transformants compared with wild type (WT). In addition, the GA content was 17.72 mg/g and increased by approximately 50% in GlMPC1- and GlMPC2-silenced transformants compared with WT. By assaying the expression levels of three key enzymes and the enzyme activities of isocitrate dehydrogenase (IDH) and α-ketoglutarate dehydrogenase (α-KGDH) of the TCA cycle in GlMPC1- and GlMPC2-silenced transformants, it was found that the decrease in GlMPCs activity did not significantly downregulate the TCA cycle rate, and the enzyme activity of IDH increased by 44% compared with WT. We then verified that fatty acid ß-oxidation (FAO) supplements the TCA cycle by detecting the expression levels of key enzymes involved in FAO. The results showed that compared with WT, the GA content was 1.14 mg/g and reduced by approximately 40% in co-silenced transformants. KEY POINTS: • GlMPCs affects the distribution of pyruvate between mitochondria and the cytoplasm. • Acetyl-CoA produced by FAO maintains the TCA cycle. • Acetyl-CoA produced by FAO promotes the accumulation of GA.

Serum metabolomics probes the molecular mechanism of action of acupuncture on metabolic pathways related to glucose metabolism in patients with polycystic ovary syndrome-related obesity.

Polycystic ovary syndrome (PCOS) is a common endocrine syndrome, and obesity is the most common clinical manifestation. Acupuncture is effective in treating PCOS, but the differences in the biological mechanisms of acupuncture therapy and Western medicine treatment have not been determined. Thus, the purpose of this study was to find glucose metabolism-related pathways in acupuncture treatment and differentiate them from Western medical treatment. Sixty patients with PCOS-related obesity were randomly distributed into three groups: patients receiving (1) acupuncture treatment alone, (2) conventional Western medicine treatment, and (3) acupuncture combined with Western medicine treatment. A targeted metabolomics approach was used to identify small molecules and metabolites related to glucose metabolism in the serum of each group, and ultra-high-performance liquid chromatography-tandem mass spectrometry was used to analyze different metabolic fractions. The results showed acupuncture treatment modulates the activity of citric and succinic acids in the tricarboxylic acid cycle, regulates glycolytic and gluconeogenesis pathways, and improves the levels of sex hormones and energy metabolism. The intervention effects on the metabolic pathways were different between patients receiving combination therapy and patients receiving acupuncture therapy alone, suggesting that the dominant modulatory effect of Western drugs may largely conceal the efficacy of acupuncture intervention.

The effect of topiramate versus flunarizine on the non-headache symptoms of migraine.

OBJECTIVES: To investigate the impact of topiramate versus flunarizine on the non-headache symptoms (NHS) of migraine, and to observe the changes of dopamine (DA) and prolactin (PRL) before and after prophylactic treatment. METHODS: Sixty-six episodic migraine patients were enrolled and randomized 1:1 to receive either flunarizine or topiramate treatment. Clinical characteristics and NHS associated with migraine were investigated before and after prophylactic treatment. The DA and PRL levels were also determined before and after prophylactic treatment. RESULTS: The NHS of migraine in the two groups were significantly better after treatment than before treatment in premonitory phase (PP), headache phase (HP), and resolution phase (RP). The NHS in the two groups had no significant difference in PP, HP, and RP before and after treatment. In the flunarizine group, the PRL content after treatment was significantly higher than that before treatment (t = -4.097, p < 0.001), but the DA content was decreased slightly compared with that before treatment (t = 1.909, p = 0.066). There was no significant difference in PRL content (t = 1.099, p = 0.280) and DA content (t = 1.556, p = 0.130) in topiramate group before and after treatment. CONCLUSIONS: The two classical prophylactic drugs of migraine were significantly effective in treating the NHS of migraine, but there was no significant difference between the two drugs. The DA-PRL axis may be involved in the underlying mechanism of the flunarizine treatment for the NHS of migraine.

A New Strategy of Chemical Photo Grafting Metal Organic Framework to Construct NH2-UiO-66/BiOBr/PVDF Photocatalytic Membrane for Synergistic Separation and Self-Cleaning Dyes.

Photocatalytic membranes are typical multifunctional membranes that have emerged in recent years. The lack of active functional groups on the surface of membranes made of inert materials such as polyvinylidene fluoride(PVDF) makes it difficult to have a stable binding interaction with photocatalysts directly. Therefore, in this study, we developed a simple method to prepare NH2-UiO-66/BiOBr/PVDF(MUB) membranes for efficient dye treatment by grafting benzophenolic acid-functionalized NH2-UiO-66 onto the surface of membranes with photocatalytic properties under visible light irradiation using benzophenolic acid with photoinitiating ability as an anchor. The structural characteristics, photocatalytic properties, antifouling properties, and reusability of the composite membranes were investigated in subsequent experiments using a series of experiments and characterizations. The results showed that the benzophenone acid grafting method was stable and the nanoparticles were not easily dislodged. The MUB composite membrane achieved a higher dye degradation efficiency (99.2%) than the pristine PVDF membrane at 62.9% within a reaction time of 180 min. In addition, the composite membranes exhibited higher permeate fluxes for both pure and mixed dyes and also demonstrated outstanding water flux recovery (>96%) after the light self-cleaning cycle operation. This combination proved to improve the performance of the membranes instead of reducing them, increasing their durability and reusability, and helping to broaden the application areas of membrane filtration technology.

A Quantitative Approach to Determine Hydrophobe Content of Associating Polyacrylamide Using a Fluorescent Probe.

Hydrophobically associating polymers have found widespread applications in many domains due to their unique rheological behavior, which is primarily dictated by the hydrophobe content. However, the low fraction of hydrophobic monomers in polymers makes this parameter's precise and straightforward measurement difficult. Herein, a variety of hydrophobically associating polyacrylamides (HAPAM) with different alkyl chain lengths (L) and hydrophobic contents ([H]) were prepared by post-modification and accurately characterized by 1H NMR spectroscopy. The maximal fluorescence emission intensity (I) of 8-anilino-1-naphthalenesulfonic acid, which is sensitive to hydrophobic environments, was then detected in those polymer solutions and shown as a ratio to that in the polymer-free solution (I0). It was found that I/I0 for 0.5 wt% HAPAM can be scaled versus CH, which is a variate related to both L and [H], as I/I0 = 1.15 + 1.09 × 108CH3.42, which was also verified to be applicable for hydrophobic associating hydrolyzed polyacrylamide (HHAPAM). This relationship provides a handy method for determining the hydrophobic content of hydrophobically associating polymers, particularly for field applications.

Multi-stage Transformations of a Cluster-Based Metal-Organic Framework: Perturbing Crystals to Glass-Forming Liquids that Re-Crystallize at High Temperature.

Glassy and liquid state metal-organic frameworks (MOFs) are emerging type of materials subjected to intense research for their rich physical and chemical properties. In this report, we obtained the first glassy MOF that involves metal-carboxylate cluster building units via multi-stage structural transformations. This MOF is composed of linear [Mn3 (COO)6 ] node and flexible pyridyl-ethenylbenzoic linker. The crystalline MOF was first perturbed by vapor hydration and thermal dehydration to give an amorphous state, which can go through a glass transition at 505 K into a super-cooled liquid. The super-cooled liquid state is stable through a wide temperature range of 40 K and has the largest fragility index of 105, giving a broad processing window. Remarkably, the super-cooled liquid can not only be quenched into glass, but also recrystallize into the initial MOF when heated to a higher temperature above 558 K. The mechanism of the multi-stage structural transformations was studied by systematic characterizations of in situ X-ray diffraction, calorimetry, rheological, spectroscopic and pair-distribution function analysis. These multi-stage transformations not only represent a rare example of high temperature coordinative recognition and self-assembly, but also provide new MOF processing strategy through crystal-amorphous-liquid-crystal transformations.

Circular RNA circ_0002137 regulated the progression of osteosarcoma through regulating miR-433-3p/ IGF1R axis.

Current clinical treatment targeting osteosarcoma (OS) are limited for OS patients with pulmonary metastasis or relapse, which led to high mortality (70%-85%) for advanced osteosarcoma patients. Although ongoing efforts have been made to illustrate the mechanisms of tumorigenesis and progression in OS; however, it was far for us to learn a comprehensive molecular mechanism implies in OS development. In our study, we implicated a circRNA hsa_circ_0002137, which was higher expressed in osteosarcoma tumours compared with paracancerous tissue. The dysregulated expression pattern was also found in osteosarcoma cell lines. The role of circ_0002137 was explored via down- or up-regulated experiments. It was proved that down-regulation of circ_0002137 suppressed the progress of OS, including cell invasion, cell cycle and cell apoptosis. Furthermore, the correlation between circ_0002137 and miR-433-3p was predicted using bioinformatic tools and verified utilizing RNA pull-down assay and luciferase reporter assay. Interestingly, we found that the inhibitory effect of circ_0002137 on OS was dependent of insulin-like growth factor-1 receptor (IGF1R). In conclusion, it was demonstrated that circ_0002137 could restrain the progression of OS through regulating miR-433-3p/IGF1R axis, providing a comprehensive landscape of circ_0002137 in the generation and development of OS.

Pradefovir Treatment in Patients With Chronic Hepatitis B: Week 24 Results From a Multicenter, Double-Blind, Randomized, Noninferiority, Phase 2 Trial.

BACKGROUND: Pradefovir is a liver-targeted prodrug of adefovir, a nucleoside/nucleotide analogue with antiviral activity against hepatitis B virus (HBV) DNA polymerase. This phase 2 study compared the efficacy and safety of oral pradefovir (30, 45, 60, or 75 mg) versus tenofovir disoproxil fumarate (TDF; 300 mg) and aimed to identify the most appropriate dose of pradefovir for the forthcoming phase 3 study. METHODS: Treatment-naive and experienced (not on treatment >6 months) patients with chronic hepatitis B were eligible. RESULTS: A total of 240 participants were randomized and treated in the study (48 per group). Approximately 80% were hepatitis B e antigen (HBeAg) positive, and 10% had liver cirrhosis. The reductions from baseline in HBV DNA levels achieved at week 24 were 5.40, 5.34, 5.33, and 5.40 log10 IU/mL, with pradefovir doses of 30-, 45-, 60-, and 75-mg, respectively, compared with 5.12 log10 IU/mL with TDF. However, HBeAg loss was attained by more participants who received 45-, 60-, or 75-mg pradefovir than by those receiving TDF (12%, 6%, and 9% vs 3%). The TDF group exhibited a more significant increase in serum creatinine than the pradefovir 30- and 45-mg groups, and serum phosphate levels were comparable among all groups. Most adverse events (AEs) were mild (grade 1). No treatment-related severe AEs were reported. Overall, AEs and laboratory abnormalities were comparable to those in the TDF group. CONCLUSIONS: Pradefovir and TDF exhibited comparable reductions in HBV DNA levels. All treatments were safe and well tolerated. CLINICAL TRIALS REGISTRATION: NCT00230503 and China Drug Trials CTR2018042.

Counterintuitive Lanthanide Hydrolysis-Induced Assembly Mechanism.

The understanding of the hydrolysis mechanism of lanthanide ions is limited by their elusive coordination configuration and undeveloped technology. A potential solution by high-resolution mass spectroscopy studies is hindered by the lack of a stable model under electrospray ionization (ESI) conditions and the complexity of the spectra. Herein, it is demonstrated that diketonate ligands can efficiently stabilize the hydrolyzed intermediate cluster of Ln3+ under ESI conditions, and an effective mass difference fingerprint of isomorphism (MDFI) method is proposed, which can allow the determination of the nuclearity-number of the species without depth resolution. Thus, the hydrolysis of Ln3+ into an atomically precise hydroxide cluster is observed at the level of precise formulae. The species evolution upon hydrolysis is along the dominant path of {Eu3}-{Eu4}-{Eu9}-{Eu10}-{Eu11}-{Eu15}-{Eu16} and a nondominant path of {Eu3}-{Eu4}-{Eu8-1}-{Eu8-2} under the investigated conditions. The crystal of the {Eu16} species was obtained via low-temperature crystallization, and single-crystal X-ray diffraction studies show that its structure contains three octahedral {o-Ln6} units. The contradiction between multiple {o-Ln6} units in the structure and the absence in the formation process indicates that the repetitive subunit observed in the structure does not necessarily correspond to the construction units of high-nuclearity clusters. Photophysical measurements indicate that Eu16 cluster has a high total emission quantum efficacy of 12.8% in the solid state. This study provides fundamental insights into the formation, evolution, and assembly of small lanthanide hydroxide units upon hydrolysis, which is vital for the goal of directional synthesis of lanthanide hydroxide clusters.