Tenofovir versus entecavir on recurrence and mortality of hepatitis B virus-related hepatocellular carcinoma after curative therapy.

BACKGROUND: Tenofovir disoproxil fumarate (TDF) and entecavir (ETV) reduce the risk of hepatocellular carcinoma (HCC) in patients of hepatitis B. This study compared the difference between ETV and TDF on risk of HCC recurrence and mortality in patients with HBV-related HCC after curative intent treatment. METHODS: Patients with HBV-related HCC who received HCC treatment (surgery or radiofrequency ablation [RFA]) and underwent long-term ETV or TDF therapy were retrospectively included. Baseline characteristics including age, sex, antiviral therapy, liver reserve, HCC stages, pathology reports and treatment modality were obtained. The risk of tumor recurrence, all-cause mortality, HCC-related mortality, and liver function were compared. RESULTS: We identified 390 HBV-related HCC patients with curative intent treatment for HCC and treated with ETV (n = 328) or TDF (n = 62) between January 2011 and December 2020. The median age was 60 years, and 90.7% patients were males. After a median follow-up of 29 months, 186 patients developed recurrent HCC and 111 died. The baseline characteristics were comparable except more ALBI grade 3 patients in TDF group (76% vs. 48%, P < 0.001). Compared to ETV group, TDF users had lower all-cause mortality (adjusted hazard ratio [aHR]: 0.38, P = 0.003), and HCC-related mortality (aHR: 0.23, P = 0.005). Lower recurrence rate was noticed in TDF users after inverse probability of treatment weighting (IPTW). TDF users had improved ALBI grade and FIB-4 index compared with ETV groups. CONCLUSION: TDF therapy is associated with a reduced risk of HCC-related outcomes among patients with HBV-related HCC after curative intent treatment compared with ETV usage.

Formation of frameshift-stimulating RNA pseudoknots is facilitated by remodeling of their folding intermediates.

Programmed -1 ribosomal frameshifting is an essential regulation mechanism of translation in viruses and bacteria. It is stimulated by mRNA structures inside the coding region. As the structure is unfolded repeatedly by consecutive translating ribosomes, whether it can refold properly each time is important in performing its function. By using single-molecule approaches and molecular dynamics simulations, we found that a frameshift-stimulating RNA pseudoknot folds sequentially through its upstream stem S1 and downstream stem S2. In this pathway, S2 folds from the downstream side and tends to be trapped in intermediates. By masking the last few nucleotides to mimic their gradual emergence from translating ribosomes, S2 can be directed to fold from the upstream region. The results show that the intermediates are greatly suppressed, suggesting that mRNA refolding may be modulated by ribosomes. Moreover, masking the first few nucleotides of S1 favors the folding from S2 and yields native pseudoknots, which are stable enough to retrieve the masked nucleotides. We hypothesize that translating ribosomes can remodel an intermediate mRNA structure into a stable conformation, which may in turn stimulate backward slippage of the ribosome. This supports an interactive model of ribosomal frameshifting and gives an insightful account addressing previous experimental observations.

Sequencing Ultrarare Targets with Compound Nucleic Acid Cytometry.

Targeted sequencing enables sensitive and cost-effective analysis by focusing resources on molecules of interest. Existing methods, however, are limited in enrichment power and target capture length. Here, we present a novel method that uses compound nucleic acid cytometry to achieve million-fold enrichments of molecules >10 kbp in length using minimal prior target information. We demonstrate the approach by sequencing HIV proviruses in infected individuals. Our method is useful for rare target sequencing in research and clinical applications, including for identifying cancer-associated mutations or sequencing viruses infecting cells.

Accurate Bulk Quantitation of Droplet Digital Polymerase Chain Reaction.

Droplet digital PCR provides superior accuracy for nucleic acid quantitation. The requirement of microfluidics to generate and analyze the emulsions, however, is a barrier to its adoption, particularly in low resource settings or clinical laboratories. Here, we report a novel method to prepare ddPCR droplets by vortexing and readout of the results by bulk analysis of recovered amplicons. We demonstrate the approach by accurately quantitating SARS-CoV-2 sequences using entirely bulk processing and no microfluidics. Our approach for quantitating reactions should extend to all digital assays that generate amplicons, including digital PCR and LAMP conducted in droplets, microchambers, or nanoliter wells. More broadly, our approach combines important attributes of ddPCR, including enhanced accuracy and robustness to inhibition, with the high-volume sample processing ability of quantitative PCR.

Resolution-exchanged structural modeling and simulations jointly unravel that subunit rolling underlies the mechanism of programmed ribosomal frameshifting.

MOTIVATION: Programmed ribosomal frameshifting (PRF) is widely used by viruses and bacteria to produce different proteins from a single mRNA template. How steric hindrance of a PRF-stimulatory mRNA structure transiently modifies the conformational dynamics of the ribosome, and thereby allows tRNA slippage, remains elusive. RESULTS: Here, we leverage linear response theories and resolution-exchanged simulations to construct a structural/dynamics model that connects and rationalizes existing structural, single-molecule and mutagenesis data by resolution-exchanged structural modelling and simulations. Our combined theoretical techniques provide a temporal and spatial description of PRF with unprecedented mechanistic details. We discover that ribosomal unfolding of the PRF-stimulating pseudoknot exerts resistant forces on the mRNA entrance of the ribosome, and thereby drives 30S subunit rolling. Such motion distorts tRNAs, leads to tRNA slippage, and in turn serves as a delicate control of cis-element's unwinding forces over PRF. AVAILABILITY AND IMPLEMENTATION: All the simulation scripts and computational implementations of our methods/analyses (including linear response theory) are included in the bioStructureM suite, provided through GitHub at https://github.com/Yuan-Yu/bioStructureM. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Coordination among tertiary base pairs results in an efficient frameshift-stimulating RNA pseudoknot.

Frameshifting is an essential process that regulates protein synthesis in many viruses. The ribosome may slip backward when encountering a frameshift motif on the messenger RNA, which usually contains a pseudoknot structure involving tertiary base pair interactions. Due to the lack of detailed molecular explanations, previous studies investigating which features of the pseudoknot are important to stimulate frameshifting have presented diverse conclusions. Here we constructed a bimolecular pseudoknot to dissect the interior tertiary base pairs and used single-molecule approaches to assess the structure targeted by ribosomes. We found that the first ribosome target stem was resistant to unwinding when the neighboring loop was confined along the stem; such constrained conformation was dependent on the presence of consecutive adenosines in this loop. Mutations that disrupted the distal base triples abolished all remaining tertiary base pairs. Changes in frameshifting efficiency correlated with the stem unwinding resistance. Our results demonstrate that various tertiary base pairs are coordinated inside a highly efficient frameshift-stimulating RNA pseudoknot and suggest a mechanism by which mechanical resistance of the pseudoknot may persistently act on translocating ribosomes.

Using cluster analysis to explore mortality patterns associated with tropical cyclones.

Understanding the circumstances and conditions surrounding disaster-attributed deaths may contribute to designing and implementing emergency preparedness and response programmes. This paper introduces a three-step cluster analysis of multiple binary variables to investigate mortality patterns related to tropical cyclones. It is designed to overcome the difficulties of performing cluster analysis in a disaster database that is composed in part of nominal variables and is unavoidably incomplete owing to missing information. The first step in the process codes all variables as binary data in order to accommodate the nominal variables. The second step calculates Spearman's rank correlation coefficients for pairs of variables. And the third step subjects the correlation coefficients to cluster analysis. Data related to 1,575 deaths attributed to tropical cyclones (also known as typhoons) that struck Taiwan between 2000 and 2015 are used to illustrate the method. The results yield two distinct groups of variables that are worthy of further exploration.

Reactivity of a Fe(III)-Bound Methoxide Supported with a Tris(thiolato)phosphine Ligand: Activation of C-Cl Bond in CH2Cl2 by Nucleophilic Attack of a Fe(III)-OCH3 Moiety.

Two mononuclear nonheme Fe(III) complexes, [PPh4][Fe(III)(PS3″)(OCH3)] (1) and [PPh4][Fe(III)(PS3″)(Cl)] (2), supported by a tris(benzenethiolato)phosphine derivative PS3″ (PS3″ = P(C6H3-3-Me3Si-2-S)3(3-)) have been synthesized and characterized. The structures resolved from X-ray crystallography show that Fe(III) centers in both complexes adopt distorted trigonal-bipyramidal geometry with a methoxide or a chloride binding in the axial position. The magnetic data for both are consistent with intermediate-spin Fe(III) centers with a C3 symmetry (S = 3/2 ground state). The bound methoxide in 1 is labile and can be replaced by a CH3CN molecule. The forming Fe(III)-CH3CN species can be further reduced by cobaltcene quantitatively to a stable Fe(II)-CH3CN complex, [Fe(PS3″)(CH3CN)](-). One-electron oxidation of 2 by ferrocenium gave a Fe(IV) analogue, [Fe(IV)(PS3″)(Cl)]. Importantly, the Fe(III)-OCH3 moiety in complex 1 acts as a strong nucleophile that activates the C-Cl bond in CH2Cl2, leading to the formation of complex 2 quantitatively. Complex 1 also reacts with other electrophiles, benzyl chloride and benzyl bromide, to generate Fe(III)-X species (X = Cl or Br). The reactions were investigated and monitored by UV-vis-NIR, NMR, and ESI-MS spectroscopies.

Design of a terahertz photonic crystal transmission filter containing ferroelectric material.

The ferroelectric material KTaO3 (KTO) has a very high refractive index, which is advantageous to the photonic crystal (PC) design. KTO polycrystalline crystal has a high extinction coefficient. In this work, we perform a theoretical study of the transmission properties of a PC bandpass filter made of polycrystalline KTO at terahertz (THz) frequencies. Our results show that the defect modes of usual PC narrowband filters no longer exist because of the existence of the high loss. We provide a new PC structure for the high-extinction materials and show that it has defect modes in its transmittance spectra, providing a possible bandpass filter design in the THz region.

Prototype of biliary drug-eluting stent with photodynamic and chemotherapy using electrospinning.

BACKGROUND: The combination of biliary stent with photodynamic and chemotherapy seemed to be a beneficial palliative treatment of unresectable cholangiocarcinoma. However, by intravenous delivery to the target tumor the distribution of the drug had its limitations and caused serious side effect on non-target organs. Therefore, in this study, we are going to develop a localized eluting stent, named PDT-chemo stent, covered with gemcitabine (GEM) and hematoporphyrin (HP). METHODS: The prototype of PDT-chemo stent was made through electrospinning and electrospraying dual-processes with an electrical charge to cover the stent with a drug-storing membrane from polymer liquid. The design of prototype used PU as the material of the backing layer, and PCL/PEG blends in different molar ratio of 9:1 and of 1:4 were used in two drug-storing layers with GEM and HP loaded respectively. RESULTS: The optical microscopy revealed that the backing layer was formed in fine fibers from electrospinning, while drug-storing layers, attributed to the droplets from electrospraying process. The covered membrane, the morphology of which was observed by scanning electron microscopy (SEM), covered the stent surface homogeneously without crack appearances. The GEM had almost 100% of electrosprayed efficiency than 70% HP loaded on the covered membrane due to the different solubility of drug in PEG/PCL blends. Drug release study confirmed the two-phased drug release pattern by regulating in different molar ratio of PEG/PCL blends polymer. CONCLUSIONS: The result proves that the PDT-chemo stent is composed of a first burst-releasing phase from HP and a later slow-releasing phase from GEM eluting. This two-phase of drug eluting stent may provide a new prospect of localized and controlled release treatment for cholangiocarcinoma disease.

Neurogenic differentiation of dental pulp stem cells to neuron-like cells in dopaminergic and motor neuronal inductive media.

BACKGROUND/PURPOSE: Dental pulp stem cells (DPSCs) have been proposed as a promising source of stem cells in nerve regeneration due to their close embryonic origin and ease of harvest. The aim of this study was to evaluate the efficacy of dopaminergic and motor neuronal inductive media on transdifferentiation of human DPSCs (hDPSCs) into neuron-like cells. METHODS: Isolation, cultivation, and identification of hDPSCs were performed with morphological analyses and flow cytometry. The proliferation potential of DPSCs was evaluated with an XTT [(2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide)] assay. Media for the induction of dopaminergic and spinal motor neuronal differentiation were prepared. The efficacy of neural induction was evaluated by detecting the expression of neuron cell-specific cell markers in DPSCs by immunocytochemistry and quantitative real-time reverse transcription polymerase chain reaction (RT-PCR). RESULTS: In the XTT assay, there was a 2.6- or 2-fold decrease in DPSCs cultured in dopaminergic or motor neuronal inductive media, respectively. The proportions of ßIII-tubulin (ßIII-tub), glial fibrillary acidic protein (GFAP), and oligodendrocyte (O1)-positive cells were significantly higher in DPSCs cultured in both neuronal inductive media compared with those cultured in control media. Furthermore, hDPSC-derived dopaminergic and spinal motor neuron cells after induction expressed a higher density of neuron cell markers than those before induction. CONCLUSION: These findings suggest that in response to the neuronal inductive stimuli, a greater proportion of DPSCs stop proliferation and acquire a phenotype resembling mature neurons. Such neural crest-derived adult DPSCs may provide an alternative stem cell source for therapy-based treatments of neuronal disorders and injury.

Cutaneous manifestations of infective endocarditis as presenting signs of left atrial myxoma in a patient with acute ischemic stroke: A case report.

RATIONALE: Approximately one-fifth ischemic stroke are attributed to cardioembolism. Patients with cardioembolic stroke often develop a more severe disability and a higher risk of stroke recurrence. Cardiac myxoma, although uncommon, can serve as a potentially curable cause of acute embolic strokes. PATIENT CONCERNS: A 55-year-old male patient presented to the emergency department with acute vertigo and unsteady gait, accompanied by left upper limb numbness. Concurrently, purple-like lesions on the left hand were noticed. DIAGNOSES: Brain magnetic resonance imaging showed multiple infarctions in the posterior circulation. Additionally, skin examination showed Janeway lesions, Osler nodes and splinter hemorrhages. There was no evidence of systemic infection. Subsequently, transthoracic echocardiogram revealed a left atrial myxoma. INTERVENTION: Early surgical resection of cardiac myxoma was performed. OUTCOMES: The patient recovered well from the surgery. No recurrent embolic event was reported at 3-month postoperatively. LESSONS: Clinicians should be vigilant for skin manifestations of cardiac embolism. In patients with acute ischemic strokes, the presence of cutaneous embolic phenomena could serve as a warning sign of cardioembolism.

PURE-seq identifies Egr1 as a Potential Master Regulator in Murine Aging by Sequencing Long-Term Hematopoietic Stem Cells.

Single-cell transcriptomics is valuable for uncovering individual cell properties, particularly in highly heterogeneous systems. However, this technique often results in the analysis of many well-characterized cells, increasing costs and diluting rare cell populations. To address this, we developed PURE-seq (PIP-seq for Rare-cell Enrichment and Sequencing) for scalable sequencing of rare cells. PURE-seq allows direct cell loading from FACS into PIP-seq reactions, minimizing handling and reducing cell loss. PURE-seq reliably captures rare cells, with 60 minutes of sorting capturing tens of cells at a rarity of 1 in 1,000,000. Using PURE-seq, we investigated murine long-term hematopoietic stem cells and their transcriptomes in the context of hematopoietic aging, identifying Egr1 as a potential master regulator of hematopoiesis in the aging context. PURE-seq offers an accessible and reliable method for isolating and sequencing cells that are currently too rare to capture successfully with existing methods.

PURE-seq identifies Egr1 as a Potential Master Regulator in Murine Aging by Sequencing Long-Term Hematopoietic Stem Cells.

Single-cell transcriptomics is valuable for uncovering individual cell properties, particularly in highly heterogeneous systems. However, this technique often results in the analysis of many well-characterized cells, increasing costs and diluting rare cell populations. To address this, we developed PURE-seq (PIP-seq for Rare-cell Enrichment and Sequencing) for scalable sequencing of rare cells. PURE-seq allows direct cell loading from FACS into PIP-seq reactions, minimizing handling and reducing cell loss. PURE-seq reliably captures rare cells, with 60 minutes of sorting capturing tens of cells at a rarity of 1 in 1,000,000. Using PURE-seq, we investigated murine long-term hematopoietic stem cells and their transcriptomes in the context of hematopoietic aging, identifying Egr1 as a potential master regulator of hematopoiesis in the aging context. PURE-seq offers an accessible and reliable method for isolating and sequencing cells that are currently too rare to capture successfully with existing methods.

Effect of body mass index on mortality for diabetic patients with aortic stenosis.

BACKGROUND: Several studies suggest an "obesity paradox," associating obesity with better cardiovascular outcomes in patients with type 2 diabetes mellitus (DM) or aortic stenosis (AS) compared to normal or underweight individuals. This study explores the impact of body mass index (BMI) on diabetic patients with AS. METHODS: Between 2014 and 2019, patients with DM who underwent echocardiography were analyzed. Outcomes included all-cause mortality, cardiovascular, and non-cardiovascular death. Patients were categorized as underweight, normal weight, or obese based on BMI (<18.5, 18.5 to 27, and >27 kg/m2, respectively). RESULTS: Among 74,835 DM patients, 734 had AS. Normal weight comprised 65.5% (n=481), underweight 4.1% (N=30), and 30.4% were obese. Over a 6-year follow-up, underweight patients had significantly higher all-cause mortality (HR 1.96, 95% CI 1.22 - 3.14, p = 0.005), while obese patients had significantly lower mortality (HR 0.79, 95% CI 0.68 - 0.91, p=0.001) compared to the normal group. Regarding etiologies, underweight patients had a higher risk of non-cardiovascular death (HR 2.47, 95% CI 1.44-4.25, p = 0.001), while obese patients had a lower risk of cardiovascular death (HR 0.66, 95% CI 0.50-0.86, p=0.003). Subgroup analysis showed a consistent trend without significant interaction. CONCLUSIONS: BMI significantly impacts mortality in DM patients with AS. Being underweight is associated with worse non-cardiovascular death, while obesity is linked to improved cardiovascular death outcomes.

Macrophage-fibroblast crosstalk drives Arg1-dependent lung fibrosis via ornithine loading.

Monocyte-derived macrophages recruited to injured tissues induce a maladaptive fibrotic response characterized by excessive production of collagen by local fibroblasts. Macrophages initiate this programming via paracrine factors, but it is unknown whether reciprocal responses from fibroblasts enhance profibrotic polarization of macrophages. We identify macrophage-fibroblast crosstalk necessary for injury-associated fibrosis, in which macrophages induced interleukin 6 ( IL-6 ) expression in fibroblasts via purinergic receptor P2rx4 signaling, and IL-6, in turn, induced arginase 1 ( Arg1 ) expression in macrophages. Arg1 contributed to fibrotic responses by metabolizing arginine to ornithine, which fibroblasts used as a substrate to synthesize proline, a uniquely abundant constituent of collagen. Imaging of idiopathic pulmonary fibrosis (IPF) lung samples confirmed expression of ARG1 in myeloid cells, and arginase inhibition suppressed collagen expression in cultured precision-cut IPF lung slices. Taken together, we define a circuit between macrophages and fibroblasts that facilitates cross-feeding metabolism necessary for injury-associated fibrosis.

Characterization of polyhydroxyalkanoate-producing bacteria isolated from sludge of commercial pig farms for producing methyl esters.

The objectives of this work were to isolate and characterize the polyhydroxyalkanoate (PHA) producing bacteria in enriched piggery sludge and make methyl esters from PHA for industrial applications. The strain ECAe24 isolated from piggery sludge with the highest PHA production was selected to produce PHA and then methyl ester by trans-esterification using glucose as substrate under mesophilic conditions. The final product after trans-esterification consisted of approximately 75.39% of fatty acid methyl ester and was identified as decanoic acid-3-hydroxy-methyl ester, octanoic acid-3-hydroxy-methyl ester, and some other contents. The novelty of this study is to use PHA-producing bacteria from piggery sludge to make fatty acid methyl esters which can be used as materials for producing biodiesel from piggery wastes.

The chromatin repressors EZH2 and Suv4-20h coregulate cell fate specification during hippocampal development.

The cell fate transition from radial glial-like (RGL) cells to neurons and astrocytes is crucial for development and pathological conditions. Two chromatin repressors-the enhancer of zeste homolog 2 and suppressor of variegation 4-20 homolog-are expressed in RGL cells in the hippocampus, implicating these epigenetic regulators in hippocampal cell fate commitment. Using a double knockout mouse model, we demonstrated that loss of both chromatin repressors in the RGL population leads to deficits in hippocampal development. Single-nuclei RNA-Seq revealed differential gene expression and provided mechanistic insight into how the two chromatin repressors are critical for the maintenance of cycling cells in the dentate gyrus as well as the balance of cell trajectories between neuronal and astroglial lineages.