Cryo-EM structure of the periplasmic tunnel of T7 DNA-ejectosome at 2.7 Å resolution.

Hershey and Chase used bacteriophage T2 genome delivery inside Escherichia coli to demonstrate that DNA, not protein, is the genetic material. Seventy years later, our understanding of viral genome delivery in prokaryotes remains limited, especially for short-tailed phages of the Podoviridae family. These viruses expel mysterious ejection proteins found inside the capsid to form a DNA-ejectosome for genome delivery into bacteria. Here, we reconstitute the phage T7 DNA-ejectosome components gp14, gp15, and gp16 and solve the periplasmic tunnel structure at 2.7 Å resolution. We find that gp14 forms an outer membrane pore, gp15 assembles into a 210 Å hexameric DNA tube spanning the host periplasm, and gp16 extends into the host cytoplasm forming a ∼4,200 residue hub. Gp16 promotes gp15 oligomerization, coordinating peptidoglycan hydrolysis, DNA binding, and lipid insertion. The reconstituted gp15:gp16 complex lacks channel-forming activity, suggesting that the pore for DNA passage forms only transiently during genome ejection.

Simultaneously Producing H2 and H2O2 by Photocatalytic Water Splitting: Recent Progress and Future.

The solar-driven overall water splitting (2H2O→2H2 + O2) is considered as one of the most promising strategies for reducing carbon emissions and meeting energy demands. However, due to the sluggish performance and high H2 cost, there is still a big gap for the current photocatalytic systems to meet the requirements for practical sustainable H2 production. Economic feasibility can be attained through simultaneously generating products of greater value than O2, such as hydrogen peroxide (H2O2, 2H2O→H2 + H2O2). Compared with overall water splitting, this approach is more kinetically feasible and generates more high-value products of H2 and H2O2. In several years, there has been an increasing surge in exploring the possibility and substantial progress has been achieved. In this review, a concise overview of the importance and underlying principles of PIWS is first provided. Next, the reported typical photocatalysts for PIWS are discussed, including commonly used semiconductors and cocatalysts, essential design features of these photocatalysts, and connections between their structures and activities, as well as the selected approaches for enhancing their stability. Then, the techniques used to quantify H2O2 and the operando characterization techniques that can be employed to gain a thorough understanding of the reaction mechanisms are summarized. Finally, the current existing challenges and the direction needing improvement are presented. This review aims to provide a thorough summary of the most recent research developments in PIWS and sets the stage for future advancements and discoveries in this emerging area.

Bevacizumab induces ferroptosis and enhances CD8+ T cell immune activity in liver cancer via modulating HAT1 and increasing IL-9.

Bevacizumab is a recombinant humanized monoclonal immunoglobulin (Ig) G1 antibody of VEGF, and inhibits angiogenesis and tumor growth in hepatocellular carcinoma (HCC). Ferroptosis, a new form of regulated cell death function independently of the apoptotic machinery, has been accepted as an attractive target for pharmacological intervention; the ferroptosis pathway can enhance cell immune activity of anti-PD1 immunotherapy in HCC. In this study we investigated whether and how bevacizumab regulated ferroptosis and immune activity in liver cancer. Firstly, we performed RNA-sequencing in bevacizumab-treated human liver cancer cell line HepG2 cells, and found that bevacizumab significantly altered the expression of a number of genes including VEGF, PI3K, HAT1, SLC7A11 and IL-9 in liver cancer, bevacizumab upregulated 37 ferroptosis-related drivers, and downregulated 17 ferroptosis-related suppressors in particular. We demonstrated that bevacizumab triggered ferroptosis in liver cancer cells by driving VEGF/PI3K/HAT1/SLC7A11 axis. Clinical data confirmed that the expression levels of VEGF were positively associated with those of PI3K, HAT1 and SLC7A11 in HCC tissues. Meanwhile, we found that bevacizumab enhanced immune cell activity in tumor immune-microenvironment. We identified that HAT1 up-regulated miR-143 targeting IL-9 mRNA 3'UTR in liver cancer cells; bevacizumab treatment resulted in the increase of IL-9 levels and its secretion via VEGF/PI3K/HAT1/miR-143/IL-9 axis, which led to the inhibition of tumor growth in vivo through increasing the release of IL-2 and Granzyme B from activated CD8+ T cells. We conclude that in addition to inhibiting angiogenesis, bevacizumab induces ferroptosis and enhances CD8+ T cell immune activity in liver cancer. This study provides new insight into the mechanisms by which bevacizumab synergistically modulates ferroptosis and CD8+ T cell immune activity in liver cancer.

Inhibition of USP7 enhances CD8+ T cell activity in liver cancer by suppressing PRDM1-mediated FGL1 upregulation.

Lymphocyte activation gene 3 (LAG3), an immune checkpoint molecule expressed on activated T cells, functions as a negative regulator of immune responses. Persistent antigen exposure in the tumor microenvironment results in sustained LAG3 expression on T cells, contributing to T cell dysfunction. Fibrinogen-like protein 1 (FGL1) has been identified as a major ligand of LAG3, and FGL1/LAG3 interaction forms a novel immune checkpoint pathway that results in tumor immune evasion. In addition, ubiquitin-specific peptidase 7 (USP7) plays a crucial role in cancer development. In this study we investigated the role of USP7 in modulation of FGL1-mediated liver cancer immune evasion. We showed that knockdown of USP7 or treatment with USP7 inhibitor P5091 suppressed liver cancer growth by promoting CD8+ T cell activity in Hepa1-6 xenograft mice and in HepG2 or Huh7 cells co-cultured with T cells, whereas USP7 overexpression produced the opposite effect. We found that USP7 upregulated FGL1 in HepG2 and Huh7 cells by deubiquitination of transcriptional factor PR domain zinc finger protein 1 (PRDM1), which transcriptionally activated FGL1, and attenuated the CD8+ T cell activity, leading to the liver cancer growth. Interestingly, USP7 could be transcriptionally stimulated by PRDM1 as well in a positive feedback loop. P5091, an inhibitor of USP7, was able to downregulate FGL1 expression, thus enhancing CD8+ T cell activity. In an immunocompetent liver cancer mouse model, the dual blockade of USP7 and LAG3 resulted in a superior antitumor activity compared with anti-LAG3 therapy alone. We conclude that USP7 diminishes CD8+ T cell activity by a USP7/PRDM1 positive feedback loop on FGL1 production in liver cancer; USP7 might be a promising target for liver cancer immunotherapy.

Aristolochic acids-hijacked p53 promotes liver cancer cell growth by inhibiting ferroptosis.

Aristolochic acids (AAs) have been identified as a significant risk factor for hepatocellular carcinoma (HCC). Ferroptosis is a type of regulated cell death involved in the tumor development. In this study, we investigated the molecular mechanisms by which AAs enhanced the growth of HCC. By conducting bioinformatics and RNA-Seq analyses, we found that AAs were closely correlated with ferroptosis. The physical interaction between p53 and AAs in HepG2 cells was validated by bioinformatics analysis and SPR assays with the binding pocket sites containing Pro92, Arg174, Asp207, Phe212, and His214 of p53. Based on the binding pocket that interacts with AAs, we designed a mutant and performed RNA-Seq profiling. Interestingly, we found that the binding pocket was responsible for ferroptosis, GADD45A, NRF2, and SLC7A11. Functionally, the interaction disturbed the binding of p53 to the promoter of GADD45A or NRF2, attenuating the role of p53 in enhancing GADD45A and suppressing NRF2; the mutant did not exhibit the same effects. Consequently, this event down-regulated GADD45A and up-regulated NRF2, ultimately inhibiting ferroptosis, suggesting that AAs hijacked p53 to down-regulate GADD45A and up-regulate NRF2 in HepG2 cells. Thus, AAs treatment resulted in the inhibition of ferroptosis via the p53/GADD45A/NRF2/SLC7A11 axis, which led to the enhancement of tumor growth. In conclusion, AAs-hijacked p53 restrains ferroptosis through the GADD45A/NRF2/SLC7A11 axis to enhance tumor growth. Our findings provide an underlying mechanism by which AAs enhance HCC and new insights into p53 in liver cancer. Therapeutically, the oncogene NRF2 is a promising target for liver cancer.

Critical Role of Trichloramine Interaction with Dichloramine for N-Nitrosamine Formation during Breakpoint Chlorination.

Breakpoint chlorination is prevalent in drinking water and potable reuse water treatment. Breakpoint chlorination enhances the formation of N-nitrosamines through reactions that form nitrosating agents. The most recent study suggests that nitroxyl (HNO) can react with free chlorine (HOCl) to form the nitrosyl chloride (ClNO) nitrosating agent but has not experimentally verified its importance in breakpoint chlorination. This study first assessed the formation of N-nitrosamines from model N-chloro-alkylamine precursors when they were added to a mixture of HOCl and HNO-derived nitrosating agents generated by chlorinating hydroxyurea. Results demonstrated negligible N-nitrosamine formation. Instead, we observed that the interaction of NCl3 with NHCl2 (total Cl2/total N molar ratio = 2.4-3:1) produced an intermediate capable of nitrosating N-chloro-alkylamines to N-nitrosamines at yields 8-fold higher to those observed in NHCl2 treatment alone, within a very short timescale (<3 min). We examined the stoichiometry of the reaction of NCl3 with NHCl2 using a UV-spectrum-based approach. Nitrosyl chloride was proposed as the key intermediate, likely formed alongside the reformation of NHCl2. Further isotopic experiments, byproduct measurements, and kinetic modeling supported the hypotheses. Modeling indicated that the reaction of NCl3 with NHCl2 explained ∼75% of NDMA formation during breakpoint chlorination. Because NCl3 is mainly derived from the reaction of HOCl with NHCl2, controlling NHCl2 (e.g., with additional treatment) is critical for minimizing nitrosamine formation in waters where breakpoint chlorination occurs.

In situ and real-time vibrational spectroscopic characterizations of the photodegradation of nitrite in the presence of methanediol.

Nitrite (NO2-) is one of the common salts in aqueous aerosols, and its photolytic products, nitric oxide (NO) and hydroxyl radical (OH), have potential for use in the oxidation of organic matter, such as dissolved formaldehyde, methanediol (CH2(OH)2), which is regarded as the precursor of atmospheric formic acid. In this work, the simulation of UVA irradiation in an aqueous mixture of NaNO2/CH2(OH)2 was carried out via continuous exposure with a 365 nm LED lamp, and the reaction evolutions were probed by in situ and real-time infrared and Raman spectroscopy, which provided multiplexity in the identification of the relevant species and the corresponding reaction evolution. Although performing infrared absorption measurements in aqueous solution seemed impracticable due to the strong interference of water, the multiplexity of the vibrational bands of parents and products in the non-interfered infrared regimes and the conjunction with Raman spectroscopy still make it possible to perform in situ and real-time characterization of the photolytic reaction in the aqueous phase, supplementary to chromatographic approaches. During the 365 nm irradiation, NO2- and CH2(OH)2 gradually decreased, concomitant with the formation of nitrous oxide (N2O) and formate (HCOO-) in the early period and carbonate (CO32-) in the late period, as revealed by the vibrational spectra. The losses or the gains of the aforementioned species increased with increases in the concentration of CH2(OH)2 and the irradiation flux of the 365 nm UV light. The ionic product HCOO- was also confirmed by ion chromatography, but oxalate (C2O42-) was absent in the vibrational spectra and ion chromatogram. The reaction mechanism is reasonably proposed on the basis of the evolutions of the aforementioned species and the predicted thermodynamic favorableness.

Aspirin modulates succinylation of PGAM1K99 to restrict the glycolysis through NF-κB/HAT1/PGAM1 signaling in liver cancer.

Aspirin as a chemopreventive agent is able to restrict the tumor growth. Phosphoglycerate mutase 1 (PGAM1) is a key enzyme of glycolysis, playing an important role in the development of cancer. However, the underlying mechanism by which aspirin inhibits the proliferation of cancer cells is poorly understood. This study aims to identify the effects of aspirin on modulating PGAM1 enzymatic activities in liver cancer. Here, we found that aspirin attenuated the PGAM1 succinylation to suppress the PGAM1 enzymatic activities and glycolysis in hepatoma cells. Mechanically, aspirin remarkably reduced the global succinylation levels of hepatoma cells, including the PGAM1 succinylation, which led to the block of conversion from 3-phosphoglycerate (3-PG) to 2-phosphoglycerate (2-PG) in cells. Interestingly, RNA-seq analysis identified that aspirin could significantly decrease the levels of histone acetyltransferase 1 (HAT1), a writer of PGAM1 succinylation, in liver cancer. As a target of aspirin, NF-κB p65 could effectively up-regulate the expression of HAT1 in the system, resulting in the increase of PGAM1 enzymatic activities. Moreover, we observed that the PGAM1-K99R mutant failed to rescue the aspirin-induced inhibition of PGAM1 activities, glycolysis, and proliferation of hepatoma cells relative to PGAM1-WT. Functionally, aspirin down-regulated HAT1 and decreased the PGAM1 succinylation levels in the tumor tissues from mice treated with aspirin in vivo. Thus, we conclude that aspirin modulates PGAM1K99 succinylation to restrict the PGAM1 activities and glycolysis through NF-κB p65/HAT1/PGAM1 signaling in liver cancer. Our finding provides new insights into the mechanism by which aspirin inhibits glycolysis in hepatocellular carcinoma.

Aspirin triggers ferroptosis in hepatocellular carcinoma cells through restricting NF-κB p65-activated SLC7A11 transcription.

A number of studies have shown that aspirin, as commonly prescribed drug, prevents the development of hepatocellular carcinoma (HCC). Ferroptosis as a dynamic tumor suppressor plays a vital role in hepatocarcinogenesis. In this study we investigated whether aspirin affected ferroptosis in liver cancer cells. RNA-seq analysis revealed that aspirin up-regulated 4 ferroptosis-related drivers and down-regulated 5 ferroptosis-related suppressors in aspirin-treated HepG2 cells. Treatment with aspirin (4 mM) induced remarkable ferroptosis in HepG2 and Huh7 cells, which was enhanced by the ferroptosis inducer erastin (10 µM). We demonstrated that NF-κB p65 restricted ferroptosis in HepG2 and Huh7 cells through directly binding to the core region of SLC7A11 promoter and activating the transcription of ferroptosis inhibitor SLC7A11, whereas aspirin induced ferroptosis through inhibiting NF-κB p65-activated SLC7A11 transcription. Overexpression of p65 rescued HepG2 and Huh7 cells from aspirin-induced ferroptosis. HCC patients with high expression levels of SLC7A11 and p65 presented lower survival rate. Functionally, NF-κB p65 blocked the aspirin-induced ferroptosis in vitro and in vivo, which was attenuated by erastin. We conclude that aspirin triggers ferroptosis by restricting NF-κB-activated SLC7A11 transcription to suppress the growth of HCC. These results provide a new insight into the mechanism by which aspirin regulates ferroptosis in hepatocarcinogenesis. A combination of aspirin and ferroptosis inducer may provide a potential strategy for the treatment of HCC in clinic.

Heat shock protein family A member 8 serving as a co-activator of transcriptional factor ETV4 up-regulates PHLDA2 to promote the growth of liver cancer.

Heat shock protein family A member 8 (HSPA8) participates in the folding or degradation of misfolded proteins under stress and plays critical roles in cancer. In this study, we investigated the function of HSPA8 in the development of liver cancer. By analyzing the TCGA transcriptome dataset, we found that HSPA8 was upregulated in 134 clinical liver cancer tissue samples, and positively correlated with poor prognosis. IHC staining showed the nuclear and cytoplasmic localization of HSPA8 in liver cancer cells. Knockdown of HSPA8 resulted in a decrease in the proliferation of HepG2 and Huh-7 cells. ChIP-seq and RNA-seq analysis revealed that HSPA8 bound to the promoter of pleckstrin homology-like domain family A member 2 (PHLDA2) and regulated its expression. The transcription factor ETV4 in HepG2 cells activated PHLDA2 transcription. HSPA8 and ETV4 could interact with each other in the cells and colocalize in the nucleus. From a functional perspective, we demonstrated that HSPA8 upregulated PHDLA2 through the coactivating transcription factor ETV4 to enhance the growth of liver cancer in vitro and in vivo. From a therapeutic perspective, we identified both HSPA8 and PHDLA2 as novel targets in the treatment of HCC. In conclusion, this study demonstrates that HSPA8 serves as a coactivator of ETV4 and upregulates PHLDA2, leading to the growth of HCC, and is a potential therapeutic target in HCC treatment.

Amnion membranes support wound granulation in a delayed murine excisional wound model.

Chronic or delayed healing wounds constitute an ever-increasing burden on healthcare providers and patients alike. Thus, therapeutic modalities that are tailored to particular deficiencies in the delayed wound healing response are of critical importance to improve clinical outcomes. Human amnion-derived viable and devitalized allografts have demonstrated clinical efficacy in promoting the closure of delayed healing wounds, but the mechanisms responsible for this efficacy and the specific wound healing processes modulated by these tissues are not fully understood. Here, we utilized a diabetic murine excisional wound model in which healing is driven by granulation and re-epithelialization, and we applied viable (vHAMA) or devitalized (dHAMA) amnion-derived allografts to the wound bed in order to determine their effects on wound healing processes. Compared to control wounds that were allowed to heal in the absence of treatment, wounds to which vHAMA or dHAMA were applied demonstrated enhanced deposition of granulation tissue accompanied by increased cellular proliferation and increased de novo angiogenesis, while vHAMA-treated wounds also demonstrated accelerated re-epithelialization. Taken together, these data suggest that both vHAMA and dHAMA facilitate wound healing through promoting processes critical to granulation tissue formation. Further understanding of the cellular and tissue mechanisms underlying the effects of tissue-derived matrices on wound healing will enable tailored prescription of their use in order to maximize clinical benefit.

Nonaromatic Organonickel(II) Phototheranostics.

Earth-abundant metal-based theranostics, agents that integrate diagnostic and therapeutic functions within the same molecule, may hold the key to the development of low-cost personalized medicines. Here, we report a set of O-linked nonaromatic benzitripyrrin (C^N^N^N) macrocyclic organonickel(II) complexes, Ni-1-4, containing strong σ-donating M-C bonds. Complexes Ni-1-4 are characterized by a square-planar coordination geometry as inferred from the structural studies of Ni-1. They integrate photothermal therapy, photothermal imaging, and photoacoustic imaging (PAI) within one system. This makes them attractive as potential phototheranostics. Relative to traditional Ni(II) porphyrins, such as F20TPP (tetrapentafluorophenylporphyrin), the lowest energy absorption of Ni-1 is shifted into the near infrared region, presumably as a consequence of Ni-C bonding. Ultrafast transient absorption spectroscopy combined with theoretical calculations revealed that, upon photoexcitation, a higher population of ligand-centered and 3MLCT states is seen in Ni-1 relative to NiTPBP (TPBP = 6,11,16,21-tetraphenylbenziporphyrin). Encapsulating Ni-1 in 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE-PEG2000) afforded nanoparticles, Ni-1@DSPE, displaying red-shifted absorption features, as well as good photothermal conversion efficiency (∼45%) in aqueous media. Proof-of-principle experiments involving thrombus treatment were carried out both in vitro and in vivo. It was found that Ni-1@DSPE in combination with 785 nm photo-irradiation for 3 min (0.3 W/cm2) proved successful in removing blood clots from a mouse thrombus model as monitored by photoacoustic imaging (PAI). The present work highlights the promise of organonickel(II) complexes as potential theranostics and the benefits that can accrue from manipulating the excited-state features of early transition-metal complexes via, for example, interrupting π-conjugation pathways.

High-Symmetry Co/Ni Triazine Polycarboxylate Diverse Frameworks Constructed by Mx(COO)y Building Blocks: Characterization and Catalytic Performance Evaluation of p-Nitrophenol.

Three new triazine compounds [Co1.5(H3TDPAT)(H2O)3]·6H2O (1), [Co2(TCPT)(µ2-H2O)2]·OH (2), and [Ni3(TCPT)]·3OH (3) were designed and synthesized via the reaction of the symmetrical triazine ligand connected by C-N-C and C-O-C bonds with triazine poly(carboxylic acid)s ligands as the side arms: H6TDPAT (H6TDPAT = 2,4,6-tris(3,5-dicarboxylphenylamino)-1,3,5-triazine) and H3TCPT (H3TCPT = 2,4,6-tris(4-carboxyphenoxy)-1,3,5-triazine) as well as the corresponding metal salts under the solvothermal condition. Three triazine polycarboxylate frameworks were characterized by elemental analysis, infrared spectroscopy, ultraviolet spectroscopy, thermogravimetric analysis, X-ray powder diffraction, and solid fluorescent spectra in detail. The structural analysis results showed that the three-dimensional porous cage framework of compound 1 was constructed by three different polyhedral cages connected with [Co(COO)4(H2O)2] building blocks. One of the compounds, 2, is formed by twin propeller Co2(µ2-H2O)(COO)3 building blocks connecting two-dimensional layers and the intermolecular π-π interactions involved the triazine rings between the layers. While the structure of compound 3 is similar to that of 2, assembly is by Ni(COO)3 building blocks and adjacent layers of the face-to-face π-π interaction between the triazine rings. In order to explore functional properties, the catalytic reduction of p-nitrophenol (PNP) of compounds 1-3 was investigated. They exhibit excellent catalytic activity of more than 95% for reduction of PNP with a dose of 2.5 mg of the compounds.

A dehydrated, aseptically-processed human amnion/chorion allograft accelerates healing in a delayed murine excisional wound model.

Since chronic, non-healing wounds represent an increasing source of economic and temporal burden for patients who suffer from them and healthcare professionals that treat them, therapeutic modalities that promote closure of delayed and non-healing wounds are of utmost importance. Recent clinical results of allografts derived from amnion and chorion placental layers encourage further investigation of the mechanisms underlying clinical efficacy of these products for treatment of wounds. Here, we utilized a diabetic murine splinted excisional wound model to investigate the effects of a dehydrated human amnion/chorion-derived allograft (dHACA) on delayed wound healing, as well as the effects of dehydrated allograft derived solely from amnion tissue of the same donor. We examined wound healing by histological endpoint analysis, and we assessed other parameters relevant to functional wound healing in the wound bed including angiogenesis, macrophage phenotypes, proliferative activity, and gene expression. Herein we demonstrate that application of dHACA to a murine diabetic model of delayed wound progression results in better macroscale wound resolution outcomes, including rate of closure, compared to unaided wound progression, while dehydrated human amnion allograft (dHAA) fails to improve outcomes. Improved gross wound resolution observed with dHACA was accompanied by increased granulation tissue formation, proliferation and vascular ingrowth observed in the wound bed, early macrophage polarization towards anti-inflammatory phenotypes, and downregulation of pro-fibrotic gene expression. Overall, our data suggest that improvements in the rates of delayed wound closure observed from combined amnion/chorion allografts are associated with modulation of critical cellular and tissue processes commonly found to be dysregulated in delayed healing wounds, including proliferation, vascularization, inflammation, and re-epithelialization.

The Nax (SCN7A) channel: an atypical regulator of tissue homeostasis and disease.

Within an articulately characterized family of ion channels, the voltage-gated sodium channels, exists a black sheep, SCN7A (Nax). Nax, in contrast to members of its molecular family, has lost its voltage-gated character and instead rapidly evolved a new function as a concentration-dependent sensor of extracellular sodium ions and subsequent signal transducer. As it deviates fundamentally in function from the rest of its family, and since the bulk of the impressive body of literature elucidating the pathology and biochemistry of voltage-gated sodium channels has been performed in nervous tissue, reports of Nax expression and function have been sparse. Here, we investigate available reports surrounding expression and potential roles for Nax activity outside of nervous tissue. With these studies as justification, we propose that Nax likely acts as an early sensor that detects loss of tissue homeostasis through the pathological accumulation of extracellular sodium and/or through endothelin signaling. Sensation of homeostatic aberration via Nax then proceeds to induce pathological tissue phenotypes via promotion of pro-inflammatory and pro-fibrotic responses, induced through direct regulation of gene expression or through the generation of secondary signaling molecules, such as lactate, that can operate in an autocrine or paracrine fashion. We hope that our synthesis of much of the literature investigating this understudied protein will inspire more research into Nax not simply as a biochemical oddity, but also as a potential pathophysiological regulator and therapeutic target.

International Validation of the SORG Machine-learning Algorithm for Predicting the Survival of Patients with Extremity Metastases Undergoing Surgical Treatment.

BACKGROUND: The Skeletal Oncology Research Group machine-learning algorithms (SORG-MLAs) estimate 90-day and 1-year survival in patients with long-bone metastases undergoing surgical treatment and have demonstrated good discriminatory ability on internal validation. However, the performance of a prediction model could potentially vary by race or region, and the SORG-MLA must be externally validated in an Asian cohort. Furthermore, the authors of the original developmental study did not consider the Eastern Cooperative Oncology Group (ECOG) performance status, a survival prognosticator repeatedly validated in other studies, in their algorithms because of missing data. QUESTIONS/PURPOSES: (1) Is the SORG-MLA generalizable to Taiwanese patients for predicting 90-day and 1-year mortality? (2) Is the ECOG score an independent factor associated with 90-day and 1-year mortality while controlling for SORG-MLA predictions? METHODS: All 356 patients who underwent surgery for long-bone metastases between 2014 and 2019 at one tertiary care center in Taiwan were included. Ninety-eight percent (349 of 356) of patients were of Han Chinese descent. The median (range) patient age was 61 years (25 to 95), 52% (184 of 356) were women, and the median BMI was 23 kg/m2 (13 to 39 kg/m2). The most common primary tumors were lung cancer (33% [116 of 356]) and breast cancer (16% [58 of 356]). Fifty-five percent (195 of 356) of patients presented with a complete pathologic fracture. Intramedullary nailing was the most commonly performed type of surgery (59% [210 of 356]), followed by plate screw fixation (23% [81 of 356]) and endoprosthetic reconstruction (18% [65 of 356]). Six patients were lost to follow-up within 90 days; 30 were lost to follow-up within 1 year. Eighty-five percent (301 of 356) of patients were followed until death or for at least 2 years. Survival was 82% (287 of 350) at 90 days and 49% (159 of 326) at 1 year. The model's performance metrics included discrimination (concordance index [c-index]), calibration (intercept and slope), and Brier score. In general, a c-index of 0.5 indicates random guess and a c-index of 0.8 denotes excellent discrimination. Calibration refers to the agreement between the predicted outcomes and the actual outcomes, with a perfect calibration having an intercept of 0 and a slope of 1. The Brier score of a prediction model must be compared with and ideally should be smaller than the score of the null model. A decision curve analysis was then performed for the 90-day and 1-year prediction models to evaluate their net benefit across a range of different threshold probabilities. A multivariate logistic regression analysis was used to evaluate whether the ECOG score was an independent prognosticator while controlling for the SORG-MLA's predictions. We did not perform retraining/recalibration because we were not trying to update the SORG-MLA algorithm in this study. RESULTS: The SORG-MLA had good discriminatory ability at both timepoints, with a c-index of 0.80 (95% confidence interval 0.74 to 0.86) for 90-day survival prediction and a c-index of 0.84 (95% CI 0.80 to 0.89) for 1-year survival prediction. However, the calibration analysis showed that the SORG-MLAs tended to underestimate Taiwanese patients' survival (90-day survival prediction: calibration intercept 0.78 [95% CI 0.46 to 1.10], calibration slope 0.74 [95% CI 0.53 to 0.96]; 1-year survival prediction: calibration intercept 0.75 [95% CI 0.49 to 1.00], calibration slope 1.22 [95% CI 0.95 to 1.49]). The Brier score of the 90-day and 1-year SORG-MLA prediction models was lower than their respective null model (0.12 versus 0.16 for 90-day prediction; 0.16 versus 0.25 for 1-year prediction), indicating good overall performance of SORG-MLAs at these two timepoints. Decision curve analysis showed SORG-MLAs provided net benefits when threshold probabilities ranged from 0.40 to 0.95 for 90-day survival prediction and from 0.15 to 1.0 for 1-year prediction. The ECOG score was an independent factor associated with 90-day mortality (odds ratio 1.94 [95% CI 1.01 to 3.73]) but not 1-year mortality (OR 1.07 [95% CI 0.53 to 2.17]) after controlling for SORG-MLA predictions for 90-day and 1-year survival, respectively. CONCLUSION: SORG-MLAs retained good discriminatory ability in Taiwanese patients with long-bone metastases, although their actual survival time was slightly underestimated. More international validation and incremental value studies that address factors such as the ECOG score are warranted to refine the algorithms, which can be freely accessed online at https://sorg-apps.shinyapps.io/extremitymetssurvival/. LEVEL OF EVIDENCE: Level III, therapeutic study.

Toe-lift test: a novel, simple and noninvasive in vivo method for contractile evaluation of tibialis anterior muscle.

Tibialis anterior (TA) muscle has frequently been used for scientific experiments, particularly for muscle contractile assays, because of its anatomical advantages. However, classical evaluation methods for the TA muscle, such as EMG and force transducer, require experimental skills to acquire reliable results. Furthermore, because sacrificing experimental animals is usually indispensable for both methods, sequential observations cannot be performed. Therefore, developing a simple, objective, and animal friendly evaluation system was warranted. In this article, we introduce a novel, simple, and noninvasive in vivo evaluation method for the TA muscle called the toe-lift test (TLT), which is not only easy to perform but also capable of detecting contractile strength precisely. Because the TLT does not require experimental animal sacrifice, performing assessments over time, such as in sequential observation, is possible. This novel method represents a solution to the need for a simple, noninvasive, and effective method for TA muscle contractile evaluation.

Can a Bayesian belief network for survival prediction in patients with extremity metastases (PATHFx) be externally validated in an Asian cohort of 356 surgically treated patients?

BACKGROUND AND PURPOSE: Predicted survival may influence the treatment decision for patients with skeletal extremity metastasis, and PATHFx was designed to predict the likelihood of a patient dying in the next 24 months. However, the performance of prediction models could have ethnogeographical variations. We asked if PATHFx generalized well to our Taiwanese cohort consisting of 356 surgically treated patients with extremity metastasis. PATIENTS AND METHODS: We included 356 patients who underwent surgery for skeletal extremity metastasis in a tertiary center in Taiwan between 2014 and 2019 to validate PATHFx's survival predictions at 6 different time points. Model performance was assessed by concordance index (c-index), calibration analysis, decision curve analysis (DCA), Brier score, and model consistency (MC). RESULTS: The c-indexes for the 1-, 3-, 6-, 12-, 18-, and 24-month survival estimations were 0.71, 0.66, 0.65, 0.69, 0.68, and 0.67, respectively. The calibration analysis demonstrated positive calibration intercepts for survival predictions at all 6 timepoints, indicating PATHFx tended to underestimate the actual survival. The Brier scores for the 6 models were all less than their respective null model's. DCA demonstrated that only the 6-, 12-, 18-, and 24-month predictions appeared useful for clinical decision-making across a wide range of threshold probabilities. The MC was < 0.9 when the 6- and 12-month models were compared with the 12-month and 18-month models, respectively. INTERPRETATION: In this Asian cohort, PATHFx's performance was not as encouraging as those of prior validation studies. Clinicians should be cognizant of the potential decline in validity of any tools designed using data outside their particular patient population. Developers of survival prediction tools such as PATHFx might refine their algorithms using data from diverse, contemporary patients that is more reflective of the world's population.

Single-Atom Catalysts Derived from Metal-Organic Frameworks for Electrochemical Applications.

Single-atom catalysts (SACs) have received tremendous attention due to their extraordinary catalytic performances. The synthesis of this kind of catalysts is highly desired and challenging. In the last few years, metal-organic frameworks (MOFs) have been demonstrated as a promising precursor for fabricating SACs. In this review, the progress and recent advances in the synthesis of MOF-derived SACs and their electrochemical applications are summarized. First, the synthetic approaches based on MOFs and accessible characterization techniques for SACs as well as their advantages/disadvantages are discussed. Then, the electrochemical applications of these MOF-derived SACs including the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), CO2 reduction reaction (CO2 RR), nitrogen reduction reaction (NRR), and other energy-related reactions are reviewed. Finally, insights into the current challenges and future prospects of this field are briefly presented.

Application of decellularized human reticular allograft dermal matrix promotes rapid re-epithelialization in a diabetic murine excisional wound model.

BACKGROUND AIMS: The treatment and care of human wounds represent an enormous burden on the medical system and patients alike. Chronic or delayed healing wounds are characterized by the inability to form proper granulation tissue, followed by deficiencies in keratinocyte migration and wound re-epithelialization, leading to increased likelihood of infection and poor wound outcomes. Human reticular acellular dermal matrix (HR-ADM) is one type of tissue graft developed to enhance closure of delayed healing wounds that has demonstrated clinical utility through accelerating closure of lower extremity diabetic ulcers, but the mechanisms underlying this clinical success are not well understood. METHODS: The authors utilized a diabetic murine splinted excisional wound model to investigate the effects of HR-ADM application on wound closure. RESULTS: The authors demonstrate that application of HR-ADM served as a dermal scaffold and promoted rapid re-epithelialization and keratinocyte proliferation, resulting in accelerated wound closure while minimizing granulation tissue formation. HR-ADM-applied wounds also demonstrated evidence of cellular infiltration, neovascularization and collagen remodeling by the host organism. CONCLUSIONS: These data suggest that HR-ADM supports epidermal closure in delayed healing wounds and remodeling of the matrix into host tissue, lending further support to the clinical success of HR-ADM described in clinical reports.