Potential Antioxidative Activity of Homocysteine in Erythrocytes under Oxidative Stress.

Homocysteine is an amino acid containing a free sulfhydryl group, making it probably contribute to the antioxidative capacity in the body. We recently found that plasma total homocysteine (total-Hcy) concentration increased with time when whole blood samples were kept at room temperature. The present study was to elucidate how increased plasma total-Hcy is produced and explore the potential physiological role of homocysteine. Erythrocytes and leukocytes were separated and incubated in vitro; the amount of total-Hcy released by these two kinds of cells was then determined by HPLC-MS. The effects of homocysteine and methionine on reactive oxygen species (ROS) production, osmotic fragility, and methemoglobin formation in erythrocytes under oxidative stress were studied. The reducing activities of homocysteine and methionine were tested by ferryl hemoglobin (Hb) decay assay. As a result, it was discovered that erythrocytes metabolized methionine to homocysteine, which was then oxidized within the cells and released to the plasma. Homocysteine and its precursor methionine could significantly decrease Rosup-induced ROS production in erythrocytes and inhibit Rosup-induced erythrocyte's osmotic fragility increase and methemoglobin formation. Homocysteine (but not methionine) was demonstrated to enhance ferryl Hb reduction. In conclusion, erythrocytes metabolize methionine to homocysteine, which contributes to the antioxidative capability under oxidative stress and might be a supplementary protective factor for erythrocytes against ROS damage.

Alkali-catalyzed hydrothermal oxidation treatment of triclosan in soil: Mechanism, degradation pathway and toxicity evaluation.

The continuous accumulation of chlorinated organic pollutants in soil poses a potential threat to ecosystems and human health alike. Alkali-catalyzed hydrothermal oxidation (HTO) can successfully remove chlorinated organic pollutants from water, but it is rarely applied to soil remediation. In this work, we assessed this technique to degrade and detoxify triclosan (TCS) in soil and we determined the underlying mechanisms. The results showed a dechlorination efficiency of TCS (100 mg per kg soil) of 49.03 % after 120 min reaction (H2O2/soil ratio 25 mL·g-1, reaction temperature 180 °C in presence of 1 g·L-1 NaOH). It was found that soil organic constituents (humic acid, HA) and inorganic minerals (SiO2, Al2O3, and CaCO3) suppressed the dechlorination degradation of TCS, with HA having the strongest inhibitory effect. During alkali-catalyzed HTO, the TCS molecules were effectively destroyed and humic acid-like or fulvic acid-like organics with oxygen functional groups were generated. Fluorescence spectroscopy analysis showed that hydroxyl radicals (OH) were the dominant reactive species of TCS degradation in soil. On the basis of the Fukui function and the degradation intermediates, two degradation pathways were proposed. One started with cleavage of the ether bond between the benzene rings of TCS, followed by dechlorination and the opening of benzene via oxidation. The other pathway started with direct hydroxylation of the benzene rings of TCS, after which they were opened and dechlorinated through oxidation. Analysis of the soil structure before and after treatment revealed that the soil surface changed from rough to smooth without affecting soil surface elements. Finally, biotoxicity tests proved that alkali-catalyzed HTO effectively reduced the toxicity of TCS-contaminated soil. This study suggests that alkali-catalyzed hydrothermal oxidation provides an environmentally friendly approach for the treatment of soil contaminated with chlorinated organics such as TCS.

Novel Approaches for the Solid-Phase Synthesis of Dihydroquinazoline-2(1H)-One Derivatives and Biological Evaluation as Potential Anticancer Agents.

In the design of antineoplastic drugs, quinazolinone derivatives are often used as small molecule inhibitors for kinases or receptor kinases, such as the EGFR tyrosine kinase inhibitor gefitinib, p38MAP kinase inhibitor DQO-501, and BRD4 protein inhibitor PFI-1. A novel and convenient approach for the solid-phase synthesis of dihydroquinazoline-2(1H)-one derivatives was proposed and 19 different compounds were synthesized. Cytotoxicity tests showed that most of the target compounds had anti-proliferative activity against HepG-2, A2780 and MDA-MB-231 cell lines. Among them, compounds CA1-e and CA1-g had the most potent effect on A2780 cells, with IC50 values of 22.76 and 22.94 µM, respectively. In addition, in an antioxidant assay, the IC50 of CA1-7 was 57.99 µM. According to bioinformatics prediction, ERBB2, SRC, TNF receptor, and AKT1 were predicted to be the key targets and play an essential role in cancer treatment. ADMET prediction suggested 14 of the 19 compounds had good pharmacological properties, i.e., these compounds displayed clinical potential. The correct structure of the final compounds was confirmed based on LC/MS, 1H NMR, and 13C NMR.

Perturbation calculation of the uniform electron gas with a transcorrelated Hamiltonian.

With a transcorrelated Hamiltonian, we perform a many body perturbation calculation on the uniform electron gas in the high density regime. By using a correlation factor optimized for a single determinant Jastrow ansatz, the second order correlation energy is calculated as 1-ln⁡2π2ln(rs)-0.05075. This already reproduces the exact logarithmic term of the random phase approximation (RPA) result, while the constant term is roughly 7% larger than the RPA one. The close agreement with the RPA method demonstrates that the transcorrelated method offers a viable and potentially efficient method for treating metallic systems.

Comparing the Effect of Piperine and Ilepcimide on the Pharmacokinetics of Curcumin in SD Rats.

The poor bioavailability and rapid metabolism of curcumin (CUR) restrict its clinical application. Piperine (PIP), which was extracted from natural compounds, can increase the plasma concentration of curcumin in humanidad. As an artificial synthetic piperine analog, silepcimide (ILE) has significant advantages because of the low price and simple synthesis process. In this study, a simple and rapid HPLC-UV method was developed for determination of the plasma concentration of CUR, PIP,ILE and dihydrocurcumin (DHC, a metabolite of CUR) simultaneously. Meanwhile, the effects of PIP and ILE on the plasma concentration and pharmacokinetics of DHC in SD rats was studied to explore whether ILE could serve as a CUR bioavailability enhancer. The metabolic pathway of CUR was studied by comparing the differences of CUR plasma concentration between intravenous injection and oral administration over the same time period, and reacting with small intestine homogenate without microbes of SD rats. The results of drug-time curve showed that combined administration of ILE and CUR had significant effect on plasma concentrations of DHC. Repeated administration of PIP or ILE could significantly increase the plasma concentration of DHC. Plasma CUR could be detected in the samples of from intravenous injection of CUR rats, whereas, it couldn't be detected in the plasma sample form oral administration rats. CUR incubated with intestinal homogenate without intestinal bacteria could not be transformed into DHC. In conclusion, our results show that ILE can improve the bioavailability of CUR. Additionally, it was inferred that most of the CUR was reduced to DHC by NADPH when it was absorbed from gastrointestinal tract, and our results demonstrated that this pathway might be mediated by gastrointestinal microorganisms.

Binding curve of the beryllium dimer using similarity-transformed FCIQMC: Spectroscopic accuracy with triple-zeta basis sets.

We demonstrate how similarity-transformed full configuration interaction quantum Monte Carlo (FCIQMC) based on the transcorrelated Hamiltonian can be applied to make highly accurate predictions for the binding curve of the beryllium dimer, marking the first case study of a molecular system with this method. In this context, the non-Hermitian transcorrelated Hamiltonian, resulting from a similarity transformation with a Jastrow factor, serves the purpose to effectively address dynamic correlation beyond the used basis set and thus allows for obtaining energies close to the complete basis set limit from FCIQMC already with moderate basis sets and computational effort. Building on results from other explicitly correlated methods, we discuss the role of the Jastrow factor and its functional form, as well as potential sources for size consistency errors, and arrive at Jastrow forms that allow for high accuracy calculations of the vibrational spectrum of the beryllium dimer.

Degradation of FA reduces Aß neurotoxicity and Alzheimer-related phenotypes.

Dysregulation of formaldehyde (FA) has been implicated in the development of Alzheimer's Disease (AD). Elevated FA levels in Alzheimer's patients and animal models are associated with impaired cognitive functions. However, the exact role of FA in AD remains unknown. We now identified that oxidative demethylation at serine8/26 of amyloid-beta protein (Aß) induced FA generation and FA cross-linked with the lysine28 residue in the ß-turn of Aß monomer to form Aß dimers, and then accelerated Aß oligomerization and fibrillogenesis in vitro. However, Aß42 mutation in serine8/26, lysine28 abolished Aß self-aggregation. Furthermore, Aß inhibited the activity of formaldehyde dehydrogenase (FDH), the enzyme for FA degradation, resulting in FA accumulation. In turn, excess of FA stimulated Aß aggregation both in vitro and in vivo by increasing the formation of Aß oligomers and fibrils. We found that degradation of FA by formaldehyde scavenger-NaHSO3 or coenzyme Q10 reduced Aß aggregation and ameliorated the neurotoxicity, and improved the cognitive performance in APP/PS1 mice. Our study provides evidence that endogenous FA is essential for Aß self-aggregation and scavenging FA could be an effective strategy for treating AD.

Larger endothelium-dependent contractions in iliac arteries of adult SHRs are attributed to differential downregulation of TP and EP3 receptors in the vessels of WKYs and SHRs during the transition from adolescence to adulthood.

This study was to determine how endothelium-dependent contractions (EDCs) change in iliac arteries of Wistar-Kyoto (WKYs) and spontaneously hypertensive rats (SHRs) during the transition from adolescence to adulthood and the underlying mechanism(s). We also aimed to elucidate effects of L-798106, an EP3 receptor antagonist, on EDCs and the blood pressure increase in adolescent SHRs. Blood vessels were isolated for functional and biochemical analyses. EDCs were comparable in adolescent iliac arteries of both strains, and contractions to ACh, prostacyclin (PGI2), the EP3 receptor agonist sulprostone and the TP receptor agonist U46619 in adult vessels were less prominent compared with those in the adolescents, while the attenuation of vasoconstrictions to ACh, PGI2 or U46619 with age was to a lesser extent in SHRs. PGI2 production was decreased to a similar level in adult arteries. TP and EP3 expressions were downregulated in adult vessels, whereas the extent of TP downregulation was less in SHRs. L-798106 partially suppressed the vasoconstrictions to U46619 and attenuated EDCs to a greater extent than SQ29548, and administration of L-798106 blunted the blood pressure increase with age in prehypertensive SHRs. These results demonstrate the comparable EDCs in iliac arteries of the adolescents are decreased in the adults, but relatively larger EDCs in adult SHRs can be a reflection of differential downregulation of TP and EP3 receptors during the transition from adolescence to adulthood. Also, our data suggest that blockade of both TP and EP3 receptors starting from the prehypertensive stage suppresses EDCs and the development of hypertension in SHRs.

Dietary riboflavin deficiency induces ariboflavinosis and esophageal epithelial atrophy in association with modification of gut microbiota in rats.

PURPOSE: Riboflavin deficiency causes ariboflavinosis, a common nutritional deficiency disease. The purpose of this study is to investigate the effects of riboflavin deficiency on the important internal organs and its potential mechanisms. METHODS: Experiment 1, male F344 rats were randomly assigned to R6 (normal riboflavin, 6 mg/kg) and R0 (riboflavin-deficient, 0 mg/kg) groups. Experiment 2 rats were assigned to R6, R0.6 (0.6 mg/kg) and R0.06 (0.06 mg/kg) groups. Experiment 3 rats were assigned to R6 and R0 → R6 (riboflavin replenishment) groups. Bacterial communities were analyzed based on 16S rRNA gene sequencing. RESULTS: Riboflavin deficiency induced ariboflavinosis (R0.06 46.7%; R0 72%) and esophageal epithelial atrophy (R0.06 40%; R0 44%) in rats, while the R6 group did not display symptoms (P < 0.001, respectively). Esophageal epithelial atrophy occurred simultaneously (R0.06 66.7%; R0 63.6%) with ariboflavinosis or appeared alone (R0.06 33.3%; R0 36.4%). Esophagus is the most vulnerable internal organ. Riboflavin deficiency followed by replenishment (R0 → R6) was effective in treating ariboflavinosis (83.3% vs. 0%, P < 0.001) and esophageal epithelial atrophy (66.7% vs. 20%, P = 0.17). Riboflavin deficiency modulated gut microbiota composition. The several key genera (Romboutsia, Turicibacter and Clostridium sensu stricto 1) were strongly correlated with ariboflavinosis and esophageal epithelial atrophy (P < 0.01 or P < 0.05). The potential mechanism is that gut microbiota affects body's xenobiotic biodegradation and metabolism, and genomic instability. CONCLUSIONS: Riboflavin deficiency induces ariboflavinosis and esophageal epithelial atrophy by modulating the gut microbiota, and offers new Queryinsight into riboflavin deficiency and esophageal lesions.

Dietary riboflavin deficiency induces genomic instability of esophageal squamous cells that is associated with gut microbiota dysbiosis in rats.

SCOPE: Epidemiologic evidence suggests that riboflavin (RBF) deficiency is a specific nutritional predisposition for esophageal cancer. The aim of this study is to investigate the potential roles of gut microbiota in esophageal tumorigenesis caused by the RBF deficiency. METHODS: Male F344 rats were subcutaneously injected with the chemical carcinogen N-nitrosomethylbenzylamine (NMBA, 0.35 mg kg-1). Rats were assigned to 4 groups, denoted as R6 (normal RBF, 6 mg kg-1), R6N (normal RBF combined with NMBA), R6N → R0N (normal RBF conversion to RBF-deficiency), and R0N → R6N (RBF-deficiency conversion to normal RBF). Bacterial communities were analyzed based on high-throughput 16S rRNA gene sequencing. Oxidative DNA damage and double-strand break markers were studied by immunohistochemistry. RESULTS: The R6N → R0N diet enhanced the incidence of esophageal intraepithelial neoplasia (EIN, 40 weeks 66.7% vs. 25 weeks 16.7%, P < 0.05). RBF deficiency and replenishment modulated the gut microbiota composition. The gut microbiota (e.g. Caulobacteraceae, Sphingomonas and Bradyrhizobium) affected xenobiotic biodegradation and the genomic instability of the host. Furthermore, the RBF deficiency aggravated oxidative DNA damage and DNA double-strand breaks (immunohistochemistry) in the esophageal epithelium, whereas the RBF replenishment had the opposite effect (P < 0.05, respectively). CONCLUSIONS: RBF deficiency promotes NMBA-induced esophageal tumorigenesis, which is associated with gut microbiota-associated genomic instability, and offers new insights into the role of RBF deficiency in esophageal carcinogenesis.

Correction: Dietary riboflavin deficiency induces genomic instability of esophageal squamous cells that is associated with gut microbiota dysbiosis in rats.

Correction for 'Dietary riboflavin deficiency induces genomic instability of esophageal squamous cells that is associated with gut microbiota dysbiosis in rats' by Feng Pan et al., Food Funct., 2020, DOI: .

NECI: N-Electron Configuration Interaction with an emphasis on state-of-the-art stochastic methods.

We present NECI, a state-of-the-art implementation of the Full Configuration Interaction Quantum Monte Carlo (FCIQMC) algorithm, a method based on a stochastic application of the Hamiltonian matrix on a sparse sampling of the wave function. The program utilizes a very powerful parallelization and scales efficiently to more than 24 000 central processing unit cores. In this paper, we describe the core functionalities of NECI and its recent developments. This includes the capabilities to calculate ground and excited state energies, properties via the one- and two-body reduced density matrices, as well as spectral and Green's functions for ab initio and model systems. A number of enhancements of the bare FCIQMC algorithm are available within NECI, allowing us to use a partially deterministic formulation of the algorithm, working in a spin-adapted basis or supporting transcorrelated Hamiltonians. NECI supports the FCIDUMP file format for integrals, supplying a convenient interface to numerous quantum chemistry programs, and it is licensed under GPL-3.0.

Determination of plasma homocysteine with a UHPLC-MS/MS method: Application to analyze the correlation between plasma homocysteine and whole blood 5-methyltetrahydrofolate in healthy volunteers.

An ultra-high performance liquid chromatography tandem mass spectrometry method was developed for determination of homocysteine (HCY) in human plasma. The HCY was derivatized with 2-chloro-1-methylquinolinium tetrafluoroborate and isolated using solid-phase extraction. Derivatization, isolation and detection procedures were optimized. Satisfactory linearity was obtained with determination coefficients (r2 ) >0.999. The intra- and inter-day precisions were in the interval of 1.2-5.1% and accuracy was within ±7%. Mean recoveries were close to 100%. The limit of detection and the limit of quantification were 0.46 and 1.38 µmol/L, respectively. The method was then applied to investigate the relationship between plasma HCY and whole blood 5-methyltetrahydrofolate levels in healthy volunteers. The results revealed that the plasma level of HCY was significantly negatively correlated to whole blood 5-methyltetrahydrofolate in volunteers.

Decreased plasma riboflavin is associated with poor prognosis, invasion, and metastasis in esophageal squamous cell carcinoma.

BACKGROUND: Riboflavin deficiency confers a predisposition for esophageal cancer. The role of plasma riboflavin levels in development and prognosis of individuals with digestive tract inflammation and ulcer (DTIU), digestive tract polyps (DTPs), and ESCC is not well understood. METHODS: We performed a cross-sectional study, including 177 DTIU, 80 DTP, and 324 ESCC cases, to measure the plasma riboflavin levels among the three populations. Correlation between plasma riboflavin levels (categorized as ≥31.8, 6.5-31.8 and ≤6.5 nmol/L groups) and clinical characteristics, as well as survival of ESCC patients (556 cases) was analyzed. RESULTS: There was no difference in plasma riboflavin levels between DTIU, DTP, and ESCC cases (P > 0.05). Plasma riboflavin levels were inversely correlated with invasive depth (correlation coefficient = -0.09, P = 0.026) and lymph node metastasis (correlation coefficient = -0.11, P = 0.010) of ESCC, and ESCC patients with low riboflavin levels had poor recurrence-free survival (P = 0.035) and overall survival (P = 0.003). Decreased riboflavin was a prognostic factor for poor overall survival (HR = 1.91, 95% CI = 1.19-3.07, P = 0.007). CONCLUSIONS: Plasma riboflavin levels in DTIU, DTP, and ESCC patients are similar. Plasma riboflavin levels are associated with the development and prognosis of ESCC.

Dietary riboflavin deficiency promotes N-nitrosomethylbenzylamine-induced esophageal tumorigenesis in rats by inducing chronic inflammation.

Epidemiological studies in high-incidence areas of esophageal cancer in China suggest that environmental carcinogen N-nitrosomethylbenzylamine (NMBA) and riboflavin (RBF) deficiency may be the main risk factors for esophageal cancer. However, it is not clear that the combination induces cancer. Here, experiment (Exp) 1 evaluated the effects of NMBA and RBF deficiency individually or in combination on esophageal tumorigenesis. Male F344 rats were randomly assigned to 4 groups into a 2 (no NMBA vs. NMBA) × 2 (normal RBF vs. RBF-deficient) factorial design, including normal RBF (6 mg/kg, R6), RBF-deficient (0 mg/kg, R0), normal RBF combined with NMBA (R6N), and RBF-deficient combined with NMBA (R0N) groups. The Exp 2 explored the effects of RBF deficiency at different doses combined with NMBA (0.6 mg/kg, R0.6N; 0.06 mg/kg, R0.06N) on esophageal tumorigenesis. Results showed that R0N enhanced the incidence of esophageal intraepithelial neoplasia (EIN, 53.3%, P = 0.06), including carcinoma in situ, whereas R6N mainly induced the occurrence of esophageal benign hyperplasia (38.9%) and EIN (16.7%). RBF deficiency promotes EIN in a dose-dependent manner, and R0.06N significantly increases the incidence of EIN (57.9%, P < 0.05). Gene expression profiling demonstrated that inflammatory cytokines were highly expressed in R0N EIN tissues, whereas R6N EIN tissues had a proliferation and differentiation gene signature (fold-change > 1.5). Furthermore, RBF deficiency aggravated oxidative DNA damage (8-OHdG) and double-strand breaks (γH2AX) (P < 0.05). Our results suggest that RBF deficiency causes chronic inflammation-associated genomic instability contributes to NMBA-induced esophageal tumorigenesis.

New insight into Alzheimer's disease: Light reverses Aß-obstructed interstitial fluid flow and ameliorates memory decline in APP/PS1 mice.

INTRODUCTION: Pharmacological therapies to treat Alzheimer's disease (AD) targeting "Aß" have failed for over 100 years. Low levels of laser light can disassemble Aß. In this study, we investigated the mechanisms that Aß-blocked extracellular space (ECS) induces memory disorders in APP/PS1 transgenic mice and addressed whether red light (RL) at 630 nm rescues cognitive decline by reducing Aß-disturbed flow of interstitial fluid (ISF). METHODS: We compared the heating effects on the brains of rats illuminated with laser light at 630, 680, and 810 nm for 40 minutes, respectively. Then, a light-emitting diode with red light at 630 nm (LED-RL) was selected to illuminate AD mice. The changes in the structure of ECS in the cortex were examined by fluorescent double labeling. The volumes of ECS and flow speed of ISF were quantified by magnetic resonance imaging. Spatial memory behaviors in mice were evaluated by the Morris water maze. Then, the brains were sampled for biochemical analysis. RESULTS: RL at 630 nm had the least heating effects than other wavelengths associated with ~49% penetration ratio into the brains. For the molecular mechanisms, Aß could induce formaldehyde (FA) accumulation by inactivating FA dehydrogenase. Unexpectedly, in turn, FA accelerated Aß deposition in the ECS. However, LED-RL treatment not only directly destroyed Aß assembly in vitro and in vivo but also activated FA dehydrogenase to degrade FA and attenuated FA-facilitated Aß aggregation. Subsequently, LED-RL markedly smashed Aß deposition in the ECS, recovered the flow of ISF, and rescued cognitive functions in AD mice. DISCUSSION: Aß-obstructed ISF flow is the direct reason for the failure of the developed medicine delivery from superficial into the deep brain in the treatment of AD. The phototherapy of LED-RL improves memory by reducing Aß-blocked ECS and suggests that it is a promising noninvasive approach to treat AD.

Synthesis and Evaluation of Pyridoxal Hydrazone and Acylhydrazone Compounds as Potential Angiogenesis Inhibitors.

BACKGROUND/AIMS: Hydrazone and acylhydrazone derivatives, which are produced from aldehyde reacting with hydrazine or acylhydrazine, have been reported to exhibit antitumor activities. However, the angionenic effects of this kind of derivatives haven't been elucidated. Here, we synthesized 12 pyridoxal hydrazone and acylhydrazone compounds and investigated their antiangiogenic effects and the underlying mechanisms. METHOD: 3-(4,5-Dimethylthiazol-2-yl)-2, 5-dipheyltetrazolium bromide assay was used to screen the inhibitory effects of the synthesized compounds on endothelial cells (ECs) proliferation. The compound with best inhibitory effect was further evaluated with wound-healing assay and tube formation assay. Calcein-Am assay was carried out to determine the content of intracellular labile iron pool (LIP). Intracellular reduced glutathione (GSH) was determined by spectrophotometry. Flow cytometry was used to determine cell cycle and apoptosis. RESULTS: Compound 10 (3-hydroxy-5-[hydroxymethyl]-2-methyl-pyridine-4-carbaldehyde-2-naphthalen-1-acetyl hydrazone) showed the best inhibitory effect on human umbilical vascular ECs proliferation, with IC50 value of 25.4 µmol/L. It not only inhibited wound-healing and tube formation of ECs, but also decreased the content of intracellular LIP and GSH. Furthermore, it arrested ECs cycle at S phase and induced cell apoptosis. CONCLUSIONS: Compound 10 exhibits antiangiogenic effects by reducing the content of intracellular LIP and GSH, and subsequently arresting cell cycle and inducing cell apoptosis.

Illumination with 630 nm Red Light Reduces Oxidative Stress and Restores Memory by Photo-Activating Catalase and Formaldehyde Dehydrogenase in SAMP8 Mice.

AIMS: Pharmacological treatments for Alzheimer's disease (AD) have not resulted in desirable clinical efficacy over 100 years. Hydrogen peroxide (H2O2), a reactive and the most stable compound of reactive oxygen species, contributes to oxidative stress in AD patients. In this study, we designed a medical device to emit red light at 630 ± 15 nm from a light-emitting diode (LED-RL) and investigated whether the LED-RL reduces brain H2O2 levels and improves memory in senescence-accelerated prone 8 mouse (SAMP8) model of age-related dementia. RESULTS: We found that age-associated H2O2 directly inhibited formaldehyde dehydrogenase (FDH). FDH inactivity and semicarbazide-sensitive amine oxidase (SSAO) disorder resulted in endogenous formaldehyde (FA) accumulation. Unexpectedly, excess FA, in turn, caused acetylcholine (Ach) deficiency by inhibiting choline acetyltransferase (ChAT) activity in vitro and in vivo. Interestingly, the 630 nm red light can penetrate the skull and the abdomen with light penetration rates of ∼49% and ∼43%, respectively. Illumination with LED-RL markedly activated both catalase and FDH in the brains, cultured cells, and purified protein solutions, all reduced brain H2O2 and FA levels and restored brain Ach contents. Consequently, LED-RL not only prevented early-stage memory decline but also rescued late-stage memory deficits in SAMP8 mice. INNOVATION: We developed a phototherapeutic device with 630 nm red light, and this LED-RL reduced brain H2O2 levels and reversed age-related memory disorders. CONCLUSIONS: The phototherapy of LED-RL has low photo toxicity and high rate of tissue penetration and noninvasively reverses aging-associated cognitive decline. This finding opens a promising opportunity to translate LED-RL into clinical treatment for patients with dementia. Antioxid. Redox Signal. 00, 000-000.

A rapid and sensitive fluorescence method for detecting urine formaldehyde in patients with Alzheimer's disease.

BACKGROUND: Morning urine formaldehyde concentrations could predict the severe degree of dementia in patients with post-stroke dementia and Alzheimer's disease. However, the routinely available technique of high-performance liquid chromatography (HPLC) for detecting urine formaldehyde requires expensive and sophisticated equipment. METHODS: We established a fluorescence spectrophotometric method by using a formaldehyde-specific fluorescent probe-NaFA (λex/em = 430/543 nm). As a standard reference method, the same batch of urine samples was analysed by HPLC with a fluorescence detector (λex/em = 346/422 nm). Then we compared the limits of detection and the limits of quantization detected by these two methods and addressed the relationship between urine formaldehyde and human cognitive ability. The Mini-Mental State Examination (MMSE), Clinical Dementia Rating and Activities of Daily Living scale were used to evaluate cognition function in 30 Alzheimer's disease patients and 52 healthy age-matched controls. RESULTS: Limits of detection and limits of quantization (1.27 and 2.48 µM) of the NaFA probe method were more accurate than Fluo-HPLC (1.52 and 2.91 µM). There was no difference in the detected formaldehyde values within day and day-to-day. Notably, only 3/82 urine formaldehyde concentrations detected by NaFA probe were below zero, while 12/82 of the values analysed by Fluo-HPLC were abnormal. More importantly, there were negatively correlated between urine formaldehyde concentrations detected by NaFA probe and MMSE scores, but positively correlated with Clinical Dementia Rating scores in Alzheimer's disease patients. CONCLUSIONS: This detecting urine formaldehyde method by NaFA probe was more rapid, sensitive and accurate than Fluo-HPLC.

Combining the Transcorrelated Method with Full Configuration Interaction Quantum Monte Carlo: Application to the Homogeneous Electron Gas.

We suggest an efficient method to resolve electronic cusps in electronic structure calculations through the use of an effective transcorrelated Hamiltonian. This effective Hamiltonian takes a simple form for plane wave bases, containing up to two-body operators only, and its use incurs almost no additional computational overhead compared to that of the original Hamiltonian. We apply this method in combination with the full configuration interaction quantum Monte Carlo (FCIQMC) method to the homogeneous electron gas. As a projection technique, the non-Hermitian nature of the transcorrelated Hamiltonian does not cause complications or numerical difficulties for FCIQMC. The rate of convergence of the total energy to the complete basis set limit is improved from [Formula: see text] to [Formula: see text], where M is the total number of orbital basis functions.