Super-resolution SRS microscopy with A-PoD.

Stimulated Raman scattering (SRS) offers the ability to image metabolic dynamics with high signal-to-noise ratio. However, its spatial resolution is limited by the numerical aperture of the imaging objective and the scattering cross-section of molecules. To achieve super-resolved SRS imaging, we developed a deconvolution algorithm, adaptive moment estimation (Adam) optimization-based pointillism deconvolution (A-PoD) and demonstrated a spatial resolution of lower than 59 nm on the membrane of a single lipid droplet (LD). We applied A-PoD to spatially correlated multiphoton fluorescence imaging and deuterium oxide (D2O)-probed SRS (DO-SRS) imaging from diverse samples to compare nanoscopic distributions of proteins and lipids in cells and subcellular organelles. We successfully differentiated newly synthesized lipids in LDs using A-PoD-coupled DO-SRS. The A-PoD-enhanced DO-SRS imaging method was also applied to reveal metabolic changes in brain samples from Drosophila on different diets. This new approach allows us to quantitatively measure the nanoscopic colocalization of biomolecules and metabolic dynamics in organelles.

Plasmonics-enhanced spikey nanorattle-based biosensor for direct SERS detection of mRNA cancer biomarkers.

We present a plasmonics-enhanced spikey nanorattle-based biosensor for direct surface-enhanced Raman scattering (SERS) detection of mRNA cancer biomarkers. Early detection of cancers such as head and neck squamous cell carcinoma (HNSCC) is critical for improving patient outcomes in regions with limited access to traditional diagnostic methods. Our method targets Keratin 14 (KRT14), a promising diagnostic mRNA biomarker for HNSCC, using a sandwich hybridization approach with magnetic beads and SERS spikey nanorattles (SpNR). We synthesized SpNR with a core-gap-shell structure to enhance SERS signals, achieving a limit of detection of 90 femtomolar. A pilot study using clinical samples demonstrated the efficacy of our biosensor in distinguishing between tissue with positive or negative diagnosis for HNSCC, highlighting its potential for rapid and sensitive cancer diagnostics in low-resource settings. This plasmonic assay offers a promising avenue for portable and high-specificity detection of nucleic acid biomarkers, with implications for early cancer detection and improved patient care, especially in middle and low-resource settings.

A micrometer head integrated microfluidic device for facile droplet size control and automatic measurement of a droplet size.

A novel microfluidic droplet generator is proposed, which can control the droplet size through turning an integrated micrometer head with ease, and the size of the produced micro-droplet can be automatically and real-time monitored by an open-sourced software and off-the-shelf hardware.

The calcium-binding proteins S100A8 and S100A9 initiate the early inflammatory program in injured peripheral nerves.

To shed light on the early immune response processes in severed peripheral nerves, we performed genome-wide transcriptional profiling and bioinformatics analyses of the proximal (P, regenerating) and distal (D, degenerating) nerve stumps on day 1 in the sciatic nerve axotomy model in rats. Multiple cell death-related pathways were activated in the degenerating D stump, whereas activation of the cytoskeletal motility and gluconeogenesis/glycolysis pathways was most prominent in the P stump of the axotomized nerve. Our bioinformatics analyses also identified the specific immunomodulatory genes of the chemokine, IL, TNF, MHC, immunoglobulin-binding Fc receptor, calcium-binding S100, matrix metalloproteinase, tissue inhibitor of metalloproteinase, and ion channel families affected in both the P and D segments. S100a8 and S100a9 were the top up-regulated genes in both the P and D segments. Stimulation of cultured Schwann cells using the purified S100A8/A9 heterodimer recapitulated activation of the myeloid cell and phagocyte chemotactic genes and pathways, which we initially observed in injured nerves. S100A8/A9 heterodimer injection into the intact nerve stimulated macrophage infiltration. We conclude that, following peripheral nerve injury, an immediate acute immune response occurs both distal and proximal to the lesion site and that the rapid transcriptional activation of the S100a8 and S100a9 genes results in S100A8/A9 hetero- and homodimers, which stimulate the release of chemokines and cytokines by activated Schwann cells and generate the initial chemotactic gradient that guides the transmigration of hematogenous immune cells into the injured nerve.

Stabilities and defect-mediated lithium-ion conduction in a ground state cubic Li3N structure.

A stable ground state structure with cubic symmetry of Li3N (c-Li3N) is found by an ab initio initially symmetric random-generated crystal structure search method. Gibbs free energy, calculated within quasi-harmonic approximation, shows that c-Li3N is the ground state structure for a wide range of temperatures. The c-Li3N structure has a negative thermal expansion coefficient at temperatures lower than room temperature, mainly due to two transverse acoustic phonon modes. This c-Li3N phase is a semiconductor with an indirect band gap of 1.90 eV within hybrid density functional calculations. We also investigate the migration and energetics of native point defects in c-Li3N, including lithium and nitrogen vacancies, interstitials, and anti-site defects. Lithium interstitials are found to have a very low migration barrier (∼ 0.12 eV) and the lowest formation energy among all possible defects. The ionic conduction in c-Li3N is thus expected to occur via an interstitial mechanism, in contrast to that in the well-known α-Li3N phase which occurs via a vacancy mechanism.

Big data analysis of treatment patterns and outcomes among elderly acute myeloid leukemia patients in the United States.

Over half of patients diagnosed with acute myeloid leukemia (AML) are 65 years or older. We examined patient characteristics, treatment patterns, and survival among elderly patients in routine clinical practice. We utilized a retrospective cohort analysis of first primary AML patients in the linked Surveillance, Epidemiology, and End Results (SEER)-Medicare database. Patients were diagnosed between January 1, 2000 and December 31, 2009, >66 years, and continuously enrolled in Medicare Part A and B in the year prior to diagnosis. Kaplan-Meier curves and Cox proportional hazards regression assessed overall survival by treatment. There were 3327 (40 %) patients who received chemotherapy within 3 months of diagnosis. Treated patients were more likely younger, male, and married, and less likely to have secondary AML and poor performance indicators and comorbidity score compared to untreated patients. In multivariate survival analysis, treated patients exhibited a significant 33 % lower risk of death compared to untreated patients. Significant survival benefits were noted with receipt of intensive and hypomethylating agent (HMA) therapies compared to no therapy. A survival benefit with allogeneic hematopoietic stem cell transplantation was seen in younger Medicare patients. This real-world study showed that about 60 % of elderly AML patients remain untreated following diagnosis. Use of anti-leukemic therapy was associated with a significant survival benefit in this elderly cohort.

Improved Biofilm Antimicrobial Activity of Polyethylene Glycol Conjugated Tobramycin Compared to Tobramycin in Pseudomonas aeruginosa Biofilms.

The objective of this study was to develop a functionally enhanced antibiotic that would improve the therapeutic activity against bacterial biofilms. Tobramycin was chemically conjugated with polyethylene glycol (PEG) via site-specific conjugation to form PEGylated-tobramycin (Tob-PEG). The antibacterial efficacy of Tob-PEG, as compared to tobramycin, was assessed on the planktonic phase and biofilms phase of Pseudomonas aeruginosa. The minimum inhibitory concentration (MIC80) of Tob-PEG was higher (13.9 µmol/L) than that of tobramycin (1.4 µmol/L) in the planktonic phases. In contrast, the Tob-PEG was approximately 3.2-fold more effective in eliminating bacterial biofilms than tobramycin. Specifically, Tob-PEG had a MIC80 lower than those exhibited by tobramycin (27.8 µmol/L vs 89.8 µmol/L). Both confocal laser scanning microscopy and scanning electron microscopy further confirmed these data. Thus, modification of antimicrobials by PEGylation appears to be a promising approach for overcoming the bacterial resistance in the established biofilms of Pseudomonas aeruginosa.

Treatment patterns and comparative effectiveness in elderly diffuse large B-cell lymphoma patients: a surveillance, epidemiology, and end results-medicare analysis.

BACKGROUND: The incidence of diffuse large B-cell lymphoma (DLBCL) occurs disproportionately in elderly patients. We evaluated real-world treatment patterns and outcomes in elderly DLBCL patients in the U.S. MATERIALS AND METHODS: A retrospective cohort analysis of 9,333 DLBCL patients from the linked Surveillance, Epidemiology, and End Results (SEER)-Medicare database was conducted. Patients were diagnosed between January 1, 2000, and December 31, 2007; were aged >66 years, and were continuously enrolled in Medicare Part A and B in the year prior to diagnosis. Within 3 months of diagnosis, 4,565 (49%) received rituximab plus chemotherapy (R+chemo), 2,181 (23%) received chemotherapy only, and 467 (5%) received rituximab monotherapy (R-mono). Cox proportional hazards regression assessed overall survival between R+chemo versus chemotherapy only and R-mono versus no treatment. RESULTS: Overall, 23% of patients received no treatment, and the proportion was higher among those aged >80 years (33%). Patients receiving R+chemo were younger and more likely white compared with those receiving chemotherapy only. Patients receiving R-mono were older and more likely female compared with those not treated. In multivariate analysis, patients receiving chemotherapy only had a twofold increased mortality risk versus R+chemo, and this was confirmed in a subanalysis of patients aged >80 years. A 91% higher mortality risk was noted with receipt of fewer than six cycles versus six cycles of chemotherapy or chemoimmunotherapy. Patients receiving R-mono had a 69% decreased mortality risk compared with patients who were not treated. CONCLUSION: This real-world analysis of elderly DLBCL patients confirmed that 23% do not receive treatment. Overall survival is higher for patients receiving R+chemo and R-mono relative to chemotherapy only and no treatment, respectively. Suboptimal durations of therapy with curative intent (fewer than six cycles) were associated with poorer outcomes.

Treatment practice in the elderly patient with chronic lymphocytic leukemia-analysis of the combined SEER and Medicare database.

The median age at diagnosis of chronic lymphocytic leukemia (CLL) is 72, but patients enrolled in randomized trials are often a decade younger. Therapy selection and outcomes in the older, comorbid population are less understood. We evaluated treatment patterns and outcomes among 2,985 first primary CLL patients from the linked Surveillance, Epidemiology, and End Results-Medicare database. There were 151 chlorambucil (CLB), 594 rituximab monotherapy (R-mono), 696 rituximab + intravenous chemotherapy (R + IV Chemo), and 1,544 IV chemo-only patients. Patients administered CLB and R-mono were the oldest and had the highest comorbidity burden while patients receiving R + IV Chemo were the youngest and had the lowest comorbidity burden (p < 0.0001). In the multivariate survival analysis, receipt of R + IV Chemo was associated with significantly lower mortality risk vs. IV Chemo-only (hazard ratio (HR) = 0.73; 95 % confidence interval (CI) 0.62-0.87) and a non-significant mortality risk reduction with R-mono vs. CLB (HR = 0.47; 95 % CI: 0.21-1.05). Older age and increasing comorbidity score were significantly associated with higher mortality. These findings suggest that chemoimmunotherapy is more effective than chemotherapy in an elderly population with a high prevalence of comorbidity, and this extends the conclusions from clinical trials in younger, medically fit patients.

The role of native defects in the transport of charge and mass and the decomposition of Li4BN3H10.

Li4BN3H10 is of great interest for hydrogen storage and for lithium-ion battery solid electrolytes because of its high hydrogen content and high lithium-ion conductivity, respectively. The practical hydrogen storage application of this complex hydride is, however, limited due to irreversibility and cogeneration of ammonia (NH3) during the decomposition. We report a first-principles density-functional theory study of native point defects and defect complexes in Li4BN3H10, and propose an atomistic mechanism for the material's decomposition that involves mass transport mediated by native defects. In light of this specific mechanism, we argue that the release of NH3 is associated with the formation and migration of negatively charged hydrogen vacancies inside the material, and it can be manipulated by the incorporation of suitable electrically active impurities. We also find that Li4BN3H10 is prone to Frenkel disorder on the Li sublattice; lithium vacancies and interstitials are highly mobile and play an important role in mass transport and ionic conduction.

Cognitively Driven Autonomous Flow Chemistry for Producing On-Demand Perovskite Quantum Dots Via Advanced Closed-Loop Feedback Control.

Recent developments in the synthesis of hybrid organic-inorganic halide perovskite quantum dots (HP-QDs) through compositional adjustments have highlighted their potential applications in the fields of photovoltaics and light sources due to their unique optoelectronic properties. However, traditional methods to fine-tune their composition involve repetitive, labor-intensive, and costly processes. Herein, the utilization of a continuous flow chemistry approach is developed, in combination with a Proportional-Integral (PI) feedback control system as an effective method for producing on-demand methylammonium lead bromoiodide (MAPbBrx I3-x ) HP-QDs. The PI feedback control allows for real-time optimization of the flow rates of halide precursor solutions (halide PSs), enabling the precise tuning of the emission wavelength of HP-QDs. HP-QDs having an emission wavelength of 550 and 650 nm are synthesized through a blue-shifted and red-shifted algorithm, respectively, from any arbitrary reaction condition within 400 s. The iterative process through the PI feedback control produces the target HP-QDs with short rise time and low overshoot. The proposed automatic flow chemistry system integrated with a universal and accessible control algorithm of PI can generate the target HP-QDs with high accuracy, stability, and robustness, demonstrating a significant advancement in constructing an autonomous flow chemistry synthetic system.

Transition Metal Dichalcogenides: Making Atomic-Level Magnetism Tunable with Light at Room Temperature.

The capacity to manipulate magnetization in 2D dilute magnetic semiconductors (2D-DMSs) using light, specifically in magnetically doped transition metal dichalcogenide (TMD) monolayers (M-doped TX2 , where M = V, Fe, and Cr; T = W, Mo; X = S, Se, and Te), may lead to innovative applications in spintronics, spin-caloritronics, valleytronics, and quantum computation. This Perspective paper explores the mediation of magnetization by light under ambient conditions in 2D-TMD DMSs and heterostructures. By combining magneto-LC resonance (MLCR) experiments with density functional theory (DFT) calculations, we show that the magnetization can be enhanced using light in V-doped TMD monolayers (e.g., V-WS2 , V-WSe2 ). This phenomenon is attributed to excess holes in the conduction and valence bands, and carriers trapped in magnetic doping states, mediating the magnetization of the semiconducting layer. In 2D-TMD heterostructures (VSe2 /WS2 , VSe2 /MoS2 ), the significance of proximity, charge-transfer, and confinement effects in amplifying light-mediated magnetism is demonstrated. We attributed this to photon absorption at the TMD layer that generates electron-hole pairs mediating the magnetization of the heterostructure. These findings will encourage further research in the field of 2D magnetism and establish a novel design of 2D-TMDs and heterostructures with optically tunable magnetic functionalities, paving the way for next-generation magneto-optic nanodevices.

Miliutine C methyl ester, a new drimane sesquiterpene and bioactive alkaloids from the stems of Miliusa velutina.

Previous results from the our research group have isolated numerous compounds, including novel ones, but the anticancer activity of Miliusa velutina has not been demonstrated. In this study, from the most active ethyl acetate extract of the stems of Miliusa velutina, seven compounds were isolated and determined structures, including a new drimane sesquiterpenoid compound named miliutine C methyl ester (1) and three bioactive alkaloids (5-7). These three alkaloids (5-7) exhibited strong anticancer activities against various cancer cell lines such as MCF-7, HepG2, HeLa, NCI H460 and normal fibroblasts. Especially, on MCF-7 and normal fibroblasts with values of IC50 (µM) in order for compounds 5 (3.38, 31.15), 6 (21.96, 102.00), 7 (7.90, greater than 300), to compare with positive control camptothecin (0.020, 4.51); which is highly noteworthy. These results contribute to elucidating and confirming the value of Miliusa velutina, similar to other published and folkloric findings.

Bioorthogonal Chemical Imaging of Cell Metabolism Regulated by Aromatic Amino Acids.

Essential aromatic amino acids (AAAs) are building blocks for synthesizing new biomasses in cells and sustaining normal biological functions. For example, an abundant supply of AAAs is important for cancer cells to maintain their rapid growth and division. With this, there is a rising demand for a highly specific, noninvasive imaging approach with minimal sample preparation to directly visualize how cells harness AAAs for their metabolism in situ. Here, we develop an optical imaging platform that combines deuterium oxide (D2O) probing with stimulated Raman scattering (DO-SRS) and integrates DO-SRS with two-photon excitation fluorescence (2PEF) into a single microscope to directly visualize the metabolic activities of HeLa cells under AAA regulation. Collectively, the DO-SRS platform provides high spatial resolution and specificity of newly synthesized proteins and lipids in single HeLa cell units. In addition, the 2PEF modality can detect autofluorescence signals of nicotinamide adenine dinucleotide (NADH) and Flavin in a label-free manner. The imaging system described here is compatible with both in vitro and in vivo models, which is flexible for various experiments. The general workflow of this protocol includes cell culture, culture media preparation, cell synchronization, cell fixation, and sample imaging with DO-SRS and 2PEF modalities.

Miliutine A acid, a new cyclofarnesane sesquiterpene from the stems of Miliusa velutina.

Six compounds were isolated from the ethyl acetate extract of the stems of Miliusa velutina, including miliutine A acid (1), a new cyclofarnesane sesquiterpenoid; miliutine B methyl ester (2), a cyclofarnesane sesquiterpenoid which was determined the absolute configuration for the first time and four known phenol derivatives (3-6). NMR spectroscopic and mass spectrometry were used for identifying relative configurations. The assignments of the absolute configurations were determined based on Electronic Circular Dichroism (ECD) and NOESY spectra analysis. All six compounds were screened for their in vitro cytotoxic activities against HepG2 cell line using the SRB assay and they showed weak or none activities.

A new sesquiterpene lactone from the leaves of Panax vietnamensis Ha et Grushv. (Vietnamese ginseng).

Panax vietnamensis (Vietnamese ginseng, Ngoc Linh ginseng) is an endemic Panax species of Vietnam. From the methanol extract of the leaves of Panax vietnamensis, five compounds (1-5) were isolated, including one new sesquiterpene lactone such as panaxolide (1) and four known compounds. The structures of the compounds (1-5) were elucidated by spectral techniques such as 1 D NMR (1H NMR, 13C NMR), 2 D NMR (COSY, HSQC, HMBC, NOESY) and mass spectrometry. The absolute configuration of 1 was determined based on the Cotton effects in the CD spectrum. All of the five compounds were screened for their in vitro growth inhibitory activities against cancerous cells (HepG2) and normal cells (fibroblast) using the SRB assay. Panaxolide (1) showed the highest potential for the growth inhibition of cancerous cells HepG2 with the IC50 values of 63.8 µM.

Function of the Speech Recognition of the Smartphone to Automatically Operate a Portable Sample Pretreatment Microfluidic System.

We proposed a portable sample pretreatment microsystem, which can be automatically operated through speech recognition in a smartphone app. The proposed sample pretreatment microsystem consists of a microfluidic chip, an air router, pressure and vacuum lines with air pump motors, six 3-way solenoid valves, and a microcontroller with a Bluetooth module. The command of a human voice conducted the whole process of DNA extraction from pathogenic bacterial samples. Thus, manual interference during the DNA extraction is eliminated, preventing any potential infection from human touch. The palm-sized sample pretreatment microsystem can be run by a portable battery or a conventional smartphone charger. Genomic DNA ofSalmonella typhimuriumwas purified on a chip in less than 1 min with an extraction efficiency of 70 ± 5%.

Origin of the structural phase transition in Li7La3Zr2O12.

Garnet-type Li(7)La(3)Zr(2)O(12) is a solid electrolyte material for Li-ion battery applications with a low-conductivity tetragonal and a high-conductivity cubic phase. Using density-functional theory and variable cell shape molecular dynamics simulations, we show that the tetragonal phase stability is dependent on a simultaneous ordering of the Li ions on the Li sublattice and a volume-preserving tetragonal distortion that relieves internal structural strain. Supervalent doping introduces vacancies into the Li sublattice, increasing the overall entropy and reducing the free energy gain from ordering, eventually stabilizing the cubic phase. We show that the critical temperature for cubic phase stability is lowered as Li vacancy concentration (dopant level) is raised and that an activated hop of Li ions from one crystallographic site to another always accompanies the transition. By identifying the relevant mechanism and critical concentrations for achieving the high conductivity phase, this work shows how targeted synthesis could be used to improve electrolytic performance.

Decomposition mechanism and the effects of metal additives on the kinetics of lithium alanate.

First-principles density functional theory studies have been carried out for native defects and transition-metal (Ti and Ni) impurities in lithium alanate (LiAlH(4)), a potential material for hydrogen storage. On the basis of our detailed analysis of the structure, energetics, and migration of lithium-, aluminium-, and hydrogen-related defects, we propose a specific atomistic mechanism for the decomposition and dehydrogenation of LiAlH(4) that involves mass transport mediated by native point defects. We also discuss how Ti and Ni impurities alter the Fermi-level position with respect to that in the undoped material, thus changing the concentration of charged defects that are responsible for mass transport. This mechanism provides an explanation for the experimentally observed lowering of the temperature for the onset of decomposition and of the activation energy for hydrogen desorption from LiAlH(4).

Imaging Sub-Cellular Methionine and Insulin Interplay in Triple Negative Breast Cancer Lipid Droplet Metabolism.

Triple negative breast cancer (TNBC) is a particularly aggressive cancer subtype that is difficult to diagnose due to its discriminating epidemiology and obscure metabolome. For the first time, 3D spatial and chemometric analyses uncover the unique lipid metabolome of TNBC under the tandem modulation of two key metabolites - insulin and methionine - using non-invasive optical techniques. By conjugating heavy water (D2O) probed Raman scattering with label-free two-photon fluorescence (TPF) microscopy, we observed altered de novo lipogenesis, 3D lipid droplet morphology, and lipid peroxidation under various methionine and insulin concentrations. Quantitative interrogation of both spatial and chemometric lipid metabolism under tandem metabolite modulation confirms significant interaction of insulin and methionine, which may prove to be critical therapeutic targets, and proposes a powerful optical imaging platform with subcellular resolution for metabolic and cancer research.