Taste traces: Capsaicin and sweeteners as anthropogenic markers in municipal wastewater

Dietary-derived substances possess significant potential as anthropogenic markers owing to the large consumption and different intake habit. To investigate and evaluate such markers, wastewater samples from 35 wastewater treatment plants across 29 Chinese cities were collected to analyze artificial sweeteners (acesulfame and cyclamate) and natural spicy compounds (capsaicin and dihydrocapsaicin). Acesulfame (mean: 14.6 μg/L), cyclamate (mean: 24.3 μg/L), and capsaicin (mean: 101 ng/L) can be further investigated as anthropogenic markers due to their high detection frequency at high concentrations. Spatial use patterns revealed that acesulfame (5.31 g/d/1000 inhabitants (inh)) and cyclamate (8.16 g/d/1000 inh) use in northern China notably surpassed that in southern China (1.79 g/d/1000 inh and 3.23 g/d/1000 inh, p < 0.05). Conversely, chili pepper use was significantly higher (p < 0.05) in southern China (6702 g/d/1000 inh) than in northern China (2751 g/d/1000 inh), signifying a preference for sweetness in the northern regions and a predilection for spiciness in the southern regions. The total annual use of acesulfame (1842 t), cyclamate (3110 t), and chili (18.4 million tonnes) in China was estimated by this study, which was close to the national statistical production. In addition, sweetener use was negatively associated with the elderly population ratio, suggesting that the elderly population might not consume sweet foods. This study reveals the dietary sources of anthropogenic markers, highlighting the need for further research on the environmental implications of such markers.

Surveillance of COVID-19 and influenza A(H1N1) prevalence in China via medicine-based wastewater biomarkers

The simultaneous monitoring of individual or multiple diseases can be achieved by selecting therapeutic medicines used to treat the primary symptoms of the condition as biomarkers in wastewater. This study proposes a novel approach to monitor the prevalence of COVID-19 and influenza A (H1N1) by selecting nine medicines to serve as biomarkers, including three antipyretics, three antivirals, and three cough suppressants. To verify our approach, wastewater samples were collected from seventeen urban and five rural wastewater treatment plants (WWTPs) in a Chinese city over a period of one year. The use of antipyretics increased notably during the COVID-19 pandemic, while the consumption of antivirals for influenza A (H1N1) rose in the post-COVID-19 pandemic period, indicating a minor spike in the occurrence of influenza A (H1N1) after the COVID-19 pandemic. Fever is a significant symptom of COVID-19 and can serve as a reliable indicator of disease prevalence. Our research found that the prevalence of COVID-19 in urban areas was significantly higher (at 78.5 %, 95 % CI: 73.4 % - 83.9 %) than in rural areas (with a prevalence of 48.1 %, 95 % CI: 42.4 % - 53.8 %). The prevalence of COVID-19 in urban areas in this study was consistent with the data reported by the Chinese center for Disease Control and Prevention (82.4 %). Continuous monitoring of WWTPs in urban areas with fluctuating populations and complex demographics can provide early disease warning. Our results demonstrate the feasibility of evaluating community disease prevalence by selecting major therapeutic medicines as biomarkers in wastewater.

M4IDP stimulates ROS elevation through inhibition of mevalonate pathway and pentose phosphate pathway to inhibit colon cancer cells

Maintaining redox homeostasis is an essential feature of cancer cells, and disrupting this homeostasis to cause oxidative stress and induce cell death is an important strategy in cancer therapy. M4IDP, a zoledronic acid derivative, can cause the death of human colorectal cancer cells by increasing the level of intracellular reactive oxygen species (ROS). However, its potential molecular mechanism is unclear. Our in vitro studies showed that treatment with M4IDP promoted oxidative stress in HCT116 cells, as measured by the decreased ratios of GSH/GSSG and NADPH/NADP+ and increased level of MDA. M4IDP could cause the decrease of GSH content, the increase of GSSG content, the decrease of NADPH content and pentose phosphate pathway flux, the downregulation of G6PD expression, the upregulation of unprenylated Rap1A and total expression of RhoA and CDC42. The increase of ROS and cytotoxicity induced by M4IDP could be reversed by the supplementation of NADPH, the overexpression of G6PD and the supplementation of GGOH. In vivo studies showed that M4IDP inhibited tumor growth in the human colorectal cancer xenograft mouse model, which was accompanied with a decreased [18F]FDG uptake. Collectively, these results provide evidence that M4IDP can promote oxidation in colon cancer cells by inhibiting mevalonate pathway and pentose phosphate pathway and produce therapeutic effect. This study revealed for the first time a possible mechanism of bisphosphonate-induced increase of ROS in malignant tumor cells. This is helpful for the development of new molecular therapeutic targets and can provide new ideas for the combined therapy of bisphosphonates in tumors.

Evaluation of eight psychoactive drugs used in Chinese cities by wastewater-based epidemiology

With rapid economic development, an increasing number of people suffer from mental health diseases, which are gradually receiving the attention of society. However, basic data from surveys of mental disorders are limited. Composite influent samples were collected from 26 wastewater treatment plants in 23 major cities in China. The concentrations of the psychoactive drugs diphenhydramine, fluoxetine, doxepin, imipramine, sulpiride, zolpidem, carbamazepine, and flunitrazepam in the wastewater were determined. The detection frequency of diphenhydramine, sulpiride, and carbamazepine was close to 100 %, whereas that of the compounds was lower than 35 %. Carbamazepine had the highest mean consumption (31.1 mg/d/1000 people), followed by diphenhydramine (10.4 mg/d/1000 people) and sulpiride (11.3 mg/d/1000 people). Wastewater-based epidemiology (WBE) estimates of the average use of the three drugs were lower than those from the drug statistics data. Consumption of diphenhydramine in northern China was higher than that in southern China. A correlation analysis of psychotropic and illicit drugs revealed a correlation between sulpiride and heroin use, which may be related to the adverse effects of sulpiride treatment after heroin withdrawal. Psychotropic drug use is associated with both economic and social factors. We found associations between the use of the three drugs and age, occupation, and obesity, which are risk factors for mental disorders. The results showed that the monitoring of psychotropic drug using WBE has a certain reference value for public health care and for improving the understanding of mental disorders.

Assessment of correlations between sildenafil use and comorbidities and lifestyle factors using wastewater-based epidemiology

Sildenafil (SIL) is widely used to treat erectile dysfunction. Information on its consumption and the factors influencing its use is limited in China. In this study, we sampled composite influent wastewater samples from 33 Chinese cities and analyzed SIL using liquid chromatography-tandem mass spectrometry. SIL consumption was estimated using wastewater-based epidemiology (WBE) and ranged from 10.6 mg/d/1000 people to 132 mg/d/1000 people, with a mean of 53 mg/d/1000 people. Prescription sales (3570 kg) accounted for 13.3% of the estimated SIL use (26842 kg) in 2018, thereby implying that SIL illicit use was greater than prescription use in China. Some regional differences were observed in SIL use, which was significantly higher in North China than South China (p < 0.05), thereby reflecting that the prevalence of SIL was affected by differences in lifestyle and socioeconomic factors. We found significant positive correlations between SIL use and consumption of allopurinol, hydrochlorothiazide, nicotine, and alcohol, thereby suggesting that the prevalence of SIL was associated with the prevalence of gout, hypertension, smoking, and drinking. Moreover, age structures, internet use, and marriage rates were positively correlated with SIL use, whereas the unemployment rate was negatively correlated with SIL use. Our study demonstrates that WBE is valuable for medical research to investigate licit and illicit drug use and to assess the underlying associations of different chemical uses.

Presence of the ketamine analog of 2-fluorodeschloroketamine residues in wastewater

Ketamine (KET) analogs are increasingly emerging as new psychoactive substances (NPS). The present report describes the first detection of the KET analog, 2-fluorodeschloroketamine (2F-DCK), in influent samples collected from nine wastewater treatment plants in seven major Chinese cities from 2018 to 2020 by wastewater-based epidemiology (WBE). An analytical method based on solid-phase extraction and subsequent gas chromatography-mass spectrometry was developed for the detection of 2F-DCK and KET. The stability experiments showed that 2F-DCK and KET remained stable in wastewater for 15 days at room and frozen temperatures, and at two pH values (pH = 7 and pH = 2), with residue amounts between 90% and 110%. KET was detected in all samples, whereas 2F-DCK was detected in only four samples: from Guangzhou in 2018, Shenzhen in 2019, and Quanzhou and Nanning in 2020, indicating that 2F-DCK has been used as early as 2018 in China. The renal clearance of 2F-DCK was predicted based on the quantitative structure-pharmacokinetic relationship model, which was used to calculate an excretion factor of 3.7. The 2F-DCK consumption in four cities ranged from 3.71 ± 0.05 to 55 ± 0.09 mg/day/1000 inh, and KET ranged from 1.3 ± 0.04 to 76.5 ± 4.63 mg/day/1000 inh. This is the first study to investigate 2F-DCK by WBE, which provides relevant real-time data on the growth of NPS use, as well as useful information for the government to develop new policies.

Insight into intrinsic ferromagnetism in quasi-2D Cr5-yTe8

Cr₅Te₈is a half metal with 2D van der Waals ferromagnetic structure and its magnetic properties can be tuned by changing the proportionality of Cr and Te. We report an investigation of magnetization and magnetic anisotropy near the critical transition region of a Cr_5-yTe₈single crystal with the static and dynamic probes, to unravel the nature of field-dependent spin-spin interactions. The magnetic transition temperatureT_Cincreasing from 255 K (at near zero-field) to 279 K (at 65 kOe along theab-plane) has been identified. Accordingly, a phase diagram of field versus transition temperature has been established. From the analysis of the field dependence of the critical behavior, we provided evidence that the scenario of 2D Heisenberg-type interactions can be employed to interpret the field-dependent magnetic transitions in Te-rich Cr_4.8Te₈. The precise picture for the field-reduced spin-spin interaction range has been obtained. The conclusion drawn from the present study demonstrated that Cr_4.8Te₈is a promising candidate for the spintronic applications with a tunable magnetic transition temperature.

[Mechanism of Xuefu Zhuyu Decoction in treatment of myocardial infarction based on network pharmacology and molecular docking]

To explore the action mechanism of Xuefu Zhuyu Decoction in treating myocardial infarction based on network pharmaco-logy and molecular docking. Active components and corresponding targets of Xuefu Zhuyu Decoction were obtained through Traditional Chinese Medicine Systems Pharmacology Database(TCMSP), and related targets of myocardial infarction were obtained through GeneCards, DisGeNET, and OMIM databases. Then the intersection targets were obtained by integrating the drug targets and disease targets. The &quot;active component-target&quot; network was constructed by Cytoscape software, and protein-protein interaction(PPI) network was drawn using STRING platform. Protein cluster analysis was carried out using MCODE. GO enrichment analysis and KEGG pathway analysis were carried out using DAVID database and ClueGO, and molecular docking was carried out using Autodock Vina and Pymol. Finally, 226 active components of Xuefu Zhuyu Decoction were obtained, 257 corresponding targets, 1 340 targets of myocardial infarction, and 109 drug and disease intersection targets were obtained. From GO enrichment analysis, 208 biological process terms, 38 molecular function terms, and 33 cellular component terms were obtained. From KEGG pathway analysis, NF-κB signaling pathway, IL-17 signaling pathway, HIF-1 signaling pathway, and other related pathways were obtained. The molecular docking results showed that the main active components(quercetin, kaempferol, β-sitosterol, luteolin, stigmasterol and baicalein) of Xuefu Zhuyu Decoction in the treatment of myocardial infarction had good binding properties with the core proteins IL6, ALB, VEGFA, TNF, MAPK3 and CASP3. The results suggested that Xuefu Zhuyu Decoction may play a role in the treatment of myocardial infarction by reducing the inflammatory response, reducing oxidative stress, inhibiting cell apoptosis, and promoting angiogenesis.

Microstructures and mechanical properties of in situ TiC-β-Ti-Nb composites with ultrafine grains fabricated by high-pressure sintering

In this study, an in situ β–Ti–Nb composites reinforced with TiC particles with an ultrafine grain size were fabricated using a powder metallurgical (PM) method. The microstructures and mechanical properties of the composites were characterized using X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and compression tests. TiC particles were formed in the ball-milled powders after annealing at 600 °C due to a chemical reaction between stearic acid and titanium. Using high-pressure sintering (HPS) on an apparatus with six tungsten carbide anvils, a fully dense β–Ti–Nb composite reinforced with fine in situ TiC particles was obtained. The TiC particles exhibit particle sizes of ~500 nm, uniformly distributed in the composite matrix, which had grain sizes of ~600 nm. Thus, the TiC–β–Ti–Nb composite show very high compression yield strength and relatively high plasticity contributed by grain refinement and TiC particles strengthening. The composite with 45 vol.% TiC exhibited excellent mechanical properties, with a yield compressive strength of 1990 MPa and plastic strain of 9.12%. More over, a modified rule-of-mixture (ROM) was presented to describe the combined strengthening effect of grain refinement and TiC particles.

High transport and excellent optical property of a two-dimensional single-layered hybrid perovskite (C4H9NH3)2PbBr4: a theoretical study

Organic–inorganic hybrid perovskites are developed to pursue high charge carrier mobility and light absorption coefficient.

Spin pump and probe in lanthanum strontium manganite/platinum bilayers

Ferromagnetic resonance driven spin pumping (FMR-SP) is a novel method to transfer spin current from the ferromagnetic (FM) layer into the adjacent normal metal (NM) layer in an FM/NM bilayer system. Consequently, the spin current could be probed in NM layer via inverse spin Hall effect (ISHE). In spite of numerous ISHE studies on FM/Pt bilayers, La_0.7Sr_0.3MnO₃(LSMO)/Pt system has been less explored and its relevant information about interface property (characterized by spin mixing conductance) and spin-charge conversion efficiency (characterized by spin Hall angle) is a matter of importance for the possible applications of spintronic devices. In this work, the technique of FMR-SP has been applied on two series of LSMO/Pt bilayers with the thickness of each layer being varied. The thickness dependences of ISHE voltage allow to extract the values of spin mixing conductance and spin Hall angle of LSMO/Pt bilayers, which are (1.8 ± 0.4) × 10¹⁹ m⁻² and (1.2 ± 0.1) % respectively. In comparison with other FM/Pt systems, LSMO/Pt has comparable spin current density and spin mixing conductance, regardless its distinct electronic structure from other ferromagnetic metals.

Estimating nicotine consumption in eight cities using sewage epidemiology based on ammonia nitrogen equivalent population

Sewage epidemiology is a real-time tool used to monitor tobacco consumption. In this study, we investigated the tobacco consumption in eight cities in Jilin province using sewage epidemiology. We collected influent wastewater samples from ten wastewater treatment plants (WWTPs) that serve nearly four million people. Mean nicotine (NIC) loads ranged from 1.42 to 14.2mg/d/capita, whereas mean cotinine (COT) loads showed lower levels with 0.33 to 2.15mg/d/capita. Population size was estimated to provide an accurate and real-time population based on ammonia nitrogen (NH₄-N) concentration in influent. To verify the NH₄-N equivalent population, we compared these results with the corresponding population estimated based on the expert knowledge of the local WWTPs operators. Daily consumption of NIC was estimated to be approximately 2.39±1.47mg/d/capita. Monte Carlo simulation was used to analyze uncertainty and variability in the number of cigarettes consumed by smokers in the range of 9.8 to 31.4 per day with a median of 16.9. The data of tobacco consumption in this study coordinated strongly with a traditional survey on the consumption of tobacco in China, indicating sewage epidemiology with NH₄-N equivalent population estimation may provide a suitable and useful tool for tobacco use monitoring.

New metal chalcogenides found in MnN-1(Gd2-xInx)SN+2 (N = 3, 4, 5): syntheses, structures, and magnetic properties

Three new metal chalcogenides have been identified in Mn_N-1(Gd_2-xIn_x)S_N+2 with N = 3, 4, and 5 via a flux-growth synthesis. All compounds crystallize in the same space group of orthorhombic Cmcm with cell constants: Mn₂GdInS₅ (1), a = 3.789(1) Å, b = 12.411(1) Å, and c = 15.489(1) Å; Mn₃Gd₂S₆ (2), a = 3.778(1) Å, b = 12.505(2) Å, and c = 19.114(2) Å; Mn₄Gd₂S₇ (3), a = 3.769(1) Å, b = 12.466(2) Å, and c = 22.289(3) Å. Compounds 1-3 form a homologous series through the modulation of the MnS unit, whose structures represent a complete system of the corresponding lillianites (^N1,N2L) of ^3,3L, ^4,4L and ^5,5L. The gradually wider slabs formed in the series result in a monotonic increase along the c dimensions from 1 to 3. Crystal 3 is the first to achieve a predicted structure of ^5,5L. Mn₂GdInS₅ (1) displays a weak antiferromagnetic (AFM) ordering at 10 K and the Weiss constant (θ) of -0.76 K. Mn₂Gd_1.5In_0.5S₅ (1a), an isostructure of 1, shifts the AFM transition temperature to 12 K and possesses a slightly larger θ constant of -6.06 K. Mn₄Gd₂S₇ (3), featuring the thickest slabs in this series, shows a significant antiferromagnetic behavior beginning at a high temperature of 70 K and has a largest θ constant of -40.25 K. A small amount of impurity α-Gd₂S₃ with an AFM transition temperature around 4 K was characterized in sample 3, which does not interfere with the magnetic ordering of 3 at much higher temperatures. These magnetic chalcogenides display band gaps of 1.66 eV for 1, 1.75 eV for 1a, and 1.44 eV for 3.

Biotransformation and detoxification of aflatoxin B1 by extracellular extract of Cladosporium uredinicola

Aflatoxin contamination of food and grain poses a serious economic and health problem globally. Aflatoxin B1 (AFB1) is extremely mutagenic and toxic as well as a potent carcinogen to both humans and livestock. In this study, the degradation of AFB1 by extracellular extract of Cladosporium uredinicola was examined using high-performance liquid chromatography (HPLC), thin-layer chromatography (TLC), and liquid chromatography mass spectrometry. Within 24 h of incubation, AFB1 was efficiently eliminated by the culture supernatant of C. uredinicola (84.5±5.7%) at 37°C; the elimination was proven to be enzymatic, and the enzyme was thermostable. The biotransformation products of AFB1 detected by HPLC and TLC were proven to be the same compound. Analysis with LCMS showed that AFB1 was bio-transformed to a structurally different compound (m/z=365 [M+Na]+), which is first reported. The cytotoxicity study to HeLa cells indicated that culture supernatant-treated AFB1 is less toxic as compared with AFB1.

Enantiomers of tetrahedral metal–organic cages: a new class of highly efficient G-quadruplex ligands with potential anticancer activities

A new class of chiral tetrahedral cages efficiently stabilized antiparallel G-quadruplex DNA with moderate enantioselectivity and displayed promising cytotoxicity against several cancer cell lines.

Effect of thermomechanical treatment on the superelasticity of Ti-7.5Nb-4Mo-2Sn biomedical alloy

Effects of thermomechanical treatment on the microstructure and superelasticity of Ti-7.5Nb-4Mo-2Sn biomedical alloy were investigated by using XRD measurement, optical microscope (OM), transmission electron microscope (TEM) and tensile tests. The titanium alloy samples were prepared by annealing at a temperature in the range of 600 to 1000°C after severe cold rolling; and the samples that were annealed at 800°C were further aged at 600 and 700°C. The volume fraction of α phases decreased while that of ω phases increase with increasing annealing temperature. The α→β transformation temperature of the alloy was determined to be between 700 and 800°C. The alloy that was annealed at 700°C exhibited a high level of superelasticity with relatively high first yield stress (σSIM) at room temperature because it contained a fine α phase. A certain amount of ω phases also resulted in an increase in σSIM, leading to an improvement in the superelasticity of the alloys that were annealed at 900 and 1000°C. Aging treatment led to the precipitations of α and ω phases in the alloy after annealing at 800°C; and the volume fraction of α phases decreased while that of ω phases increased with increasing aging temperature. Excellent superelasticity with high recovered strain (εrecoverable) and strain recovery rate (η) were obtained in the aged alloy due to the reinforcement of α and ω phases induced by aging treatment. The alloy annealed at 700°C for 0.5h exhibited the best superelasticity in all the thermomechanically treated alloys due to the strengthening from the subgrain refining and the precipitating of fine α phases.

Influence of damping constant on inverse spin hall voltage of La0.7Sr0.3MnO3(x)/platinum bilayers

Pure spin transport via spin pumping in the condition of ferromagnetic resonance can be transformed to charge current in the ferromagnetic/paramagnetic bilayer systems, based on inverse spin Hall effect (ISHE). Here, we explore La_0.7Sr_0.3MnO(x)/Pt(5.5 nm) [x = 10 to 65 nm] bilayers to investigate the influence of damping constant on spin pumping efficiency. The results show that the ISHE voltage depend on the damping constant of magnetic moment, suggesting that the precession energy tansferred to lattice/electron of normal metal is a key parameter to control the magnitude of spin current.

Poly[[diaqua-(1,10-phenanthroline-κN,N')(μ(3)-4-sulfonato-benzene-1,2-dicarboxyl-ato-κO:O,O:O)dysprosium(III)] dihydrate]

The 4-sulfophthalate trianion in the polymeric title complex, {[Dy(C(8)H(3)O(7)S)(C(12)H(8)N(2))(H(2)O)(2)]·2H(2)O}(n), bridges three water/phenanthroline-coordinated Dy(III) atoms to form a three-dimensional network architecture. The metal atom is further chelated by a carboxyl-ate group and is covalently bonded to a monodentate carboxyl-ate group and to a monodentate sulfonate group in a distorted square-anti-prismatic geometry. The coordinating and the solvent water mol-ecules are hydrogen bonded to the network. In the crystal, one solvent water mol-ecule is disordered over two positions [major component = 59 (3)%].

Poly[[diaqua-(1,10-phenanthroline-κN,N')(μ(3)-4-sulfonato-benzene-1,2-di-car-boxyl-ato-κO:O,O:O)erbium(III)] dihydrate]

The 4-sulfophthalate trianion in the polymeric complex, {[Er(C(8)H(3)O(7)S)(C(12)H(8)N(2))(H(2)O)(2)]·2H(2)O}(n), bridges three water/phenanthroline-coordinated Er(III) ions to form a three-dimensional network architecture. The metal atom is further chelated by a carboxyl-ate group and is covalently bonded to a monodentate carboxyl-ate group as well as to a monodentate sulfonate group in a distorted square anti-prismatic geometry. The coordinating water molecules and the lattice water molecules, one of which is disordered over two positions [major component 65 (3)%], are hydrogen bonded to the network.

Optical control of phase transformation in Fe-doped TiO2 nanoparticles

A series of anatase phase Fe-doped TiO2 nanoparticles are prepared by a modified sol-gel method. Spontaneous Raman spectroscopy is utilized to characterize the crystal structures of these nanoparticles and investigate their structural transformation under the exposure of a 532 nm green laser. The anatase phase of TiO2 can be effectively converted into the rutile phase with the assistance of Fe doping. It is found that the critical laser intensity for phase transformation decreases with increasing the Fe content. We ascribe this tendency to the enhanced optical absorption and the photo-induced thermal heating effect, which can be associated with the defect structure within the bandgap of Fe- TiO2 nanoparticles. Our study demonstrates an all-optical approach to pump and probe the phase transformation of metal-doped TiO2 nanoparticles.

1-Carboxymethyl-2-ethyl-4-methyl-1H-imidazol-3-ium chloride monohydrate

In the title compound, C₈H₁₃N₂O₂⁺·Cl⁻·H₂O, the methyl C atom of the ethyl group is slightly out of the imidazole plane, with an N—C(ring)—C—C torsion angle of −15.1 (2)°. In the crystal structure, there are strong inter­molecular hydrogen-bonding inter­actions between the solvent water mol­ecule, the free chloride anion and the organic cation, resulting in a two-dimensional supra­molecular network in the ab plane.

trans,trans,trans-Diaquabis(nicotinamide-κN)bis(2-nitrobenzoato-κO)cadmium(II) dihydrate

The cadmium atom in the title compound, [Cd(C₇H₄NO₄)₂(C₆H₆N₂O)₂(H₂O)₂]·2H₂O, lies on a center of inversion in an all-trans octa­hedral environment. In the crystal, the complex inter­acts with the uncoordinated water mol­ecules through O—H⋯O and N—H⋯O hydrogen bonds, forming a layered network.

2-(1-Methyl-ethoxy)-5-nitro-phenyl N-methyl-carbamate

In the title compound, C₁₁H₁₄N₂O₅, the nitro group is approximately coplanar with the benzene ring, making a dihedral angle of 4.26 (17)°. The dihedral angle between the methyl­carbamate group and the benzene ring is 72.47 (6)°. There is a strong inter­molecular N—H⋯O hydrogen bond between the N and O atoms from adjacent methyl­carbamate groups, forming a one-dimensional network along the a axis.

Inhibitions of mast cell-derived histamine release by different Flos Magnoliae species in rat peritoneal mast cells

Flos Magnoliae (FM) is a commonly used Chinese medicinal herb for symptomatic relief of allergic rhinitis, sinusitis and headache. A number of FM species have been used as substitutes or adulterants for clinical application, although the differences in their pharmacological actions have not been reported. The present study investigated the effects of six identified FM species M. biondii, M. denudata, M. kobus, M. liliflora, M. sargentiana and M. sprengeri, as well as the marker compounds magnolin and fargesin on compound 48/80-induced histamine release in rat peritoneal mast cells (RPMC) in vitro. Ethanolic extracts of all FM species produced a concentration-dependent inhibition of compound 48/80-induced histamine release in RPMC. The rank order of the IC(50)s was M. biondii<M. kobus<M. liliflora<M. denudata<M. sprengeri<M. sargentiana. The marker compound magnolin, but not fargesin, only slightly inhibited the histamine release. The contents of magnolin and fargesin, determined by using RP-HPLC, varied significantly among these FM species. Magnolin was found in M. biondii, M. kobus and M. liliflora, but not in M. denudate, M. sprengeri and M. sargentiana, while fargesin was only found in M. biondii and M. kobus. These findings provide the first evidence of differences in pharmacological actions of different FM species on mast cell-derived histamine release in vitro. In addition, the marker compounds magnolin and fargesin may not play a major role in the observed pharmacological actions of FM species.

In vitro bioactivity evaluation of titanium and niobium metals with different surface morphologies

Current orthopaedic biomaterials research mainly focuses on designing implants that could induce controlled, guided and rapid healing. In the present study, the surface morphologies of titanium (Ti) and niobium (Nb) metals were tailored to form nanoporous, nanoplate and nanofibre-like structures through adjustment of the temperature in the alkali-heat treatment. The in vitro bioactivity of these structures was then evaluated by soaking the treated samples in simulated body fluid (SBF). It was found that the morphology of the modified surface significantly influenced the apatite-inducing ability. The Ti surface with a nanofibre-like structure showed better apatite-inducing ability than the nanoporous or nanoplate surface structures. A thick dense apatite layer formed on the Ti surface with nanofibre-like structure after 1 week of soaking in SBF. It is expected that the nanofibre-like surface could achieve good apatite formation in vivo and subsequently enhance osteoblast cell adhesion and bone formation.

(2S,3S)-3-(4-Chloro-phen-yl)-8-methyl-tropane-2-carboxylic acid

In the title compound, C₁₅H₁₈ClNO₂, the inter­nal torsion angles of the tropane ring are comparable to those of tropane rings in the crystal structures reported for cocaine and its derivatives. There is an intra­molecular hydrogen bond between the N atom in the tropane ring and the O atom of the carboxyl group. The crystal structure is further stabilized by many weak C—H⋯O inter­actions between the mol­ecules in the ab plane, forming a two-dimensional supra­molecular network.

An Anti-apoptosis Gene of the Bcl-2 Family from Marine Birnavirus Inhibiting Apoptosis of Insect Cells Infected with Baculovirus

VP5 is a 15-kDa nonstructural protein encoded by a small open reading frame in 5'-terminal of segment A of the Marine Birnavirus (MABV) (strainY-6) genome. Comparisons of the amino acid sequence of the VP5 with other Bcl-2 family member proteins indicated that the VP5 protein contains Bcl-2 homology (BH) domains BH1, BH2, BH3, and BH4, but without the transmembrane region. The VP5 gene from MABV was fused to enhancing green fluorescence protein (eGFP) gene and inserted into the baculovirus genome under the control of polyhedrin gene promoter, and then was highly expressed in insect cells. The expressed VP5 was capable of enhancing insect cell viability, prevented membrane blebbing and delayed DNA internucleosomal cleavage when cells were infected with the recombinant virus. The results suggested that the VP5 of MABV is a novel anti-apoptosis gene, which could regulate the cell apoptosis-off system.

Aquabis(2-nitrobenzoato-kappaO)(1,10-phenanthroline-kappa2N,N')zinc(II)

The title compound, [Zn(C7H4NO4)2(C12H8N2)(H2O)], has been synthesized. X-Ray analysis reveals that it is a neutral zinc(II) mononuclear carboxylate complex based on mixed N- and O-donor ligands. The Zn atom is five-coordinate in a distorted trigonal-bipyramidal coordination environment involving two O atoms of two monodentate 2-nitrobenzoate molecules, two N atoms of a 1,10-phenanthroline molecule and one O atom of a water molecule. The axial positions are occupied by a carboxylate O atom from the 2-nitrobenzoate ligand and an N atom from the 1,10-phenanthroline ligand [N-Zn-O = 167.66 (9) degrees].

Effects of garlic components diallyl sulfide and diallyl disulfide on arylamine N-acetyltransferase activity and 2-aminofluorene-DNA adducts in human promyelocytic leukemia cells

Two components of garlic, diallyl sulfide (DAS) and diallyl disulfide (DADS), inhibited arylamine N-acetyltransferase (NAT) activity and 2-aminofluorene-DNA adduct in human promyelocytic leukemia cells (HL-60). The NAT activity was measured by high performance liquid chromatography assaying for amounts of N-acetyl-2-aminofluorene (2-AAF) and remaining 2-aminofluorene (2-AF). Cellular cytosols and intact cell suspensions were assayed. The inhibition of NAT activity and 2-AF-DNA adduct formation in human leukemia cells by DAS and DADS were dose-dependent and were directly proportional. The data also indicated that DAS and DADS decrease the apparent values of Km and Vmax from human leukemia cells in both assays. This is the first report of garlic components affecting human leukemia cell NAT activity and 2-AF-DNA adduct formation.

Assessment of sediment toxicity by metal speciation in different particle-size fractions of river sediment

Mobility and toxicity of metals associated with sediments are generally affected by metal speciation and granular compositions. Due to the various speciation patterns of heavy metals in sediments, it is not reliable to assess the potential toxicity of heavy metals on the aquatic environment with the total concentrations of heavy metals in sediments. The purposes of this study were to investigate the distribution of metal speciation in different particle-size fractions of sediments collected from two rivers (the Ke-Ya River and Ell-Ren River) in Taiwan, and to assess their potential toxicity to the aquatic ecosystem. Metals in the exchangeable, carbonate-bound and Fe/Mn oxide-bound forms obtained by sequential extraction were considered to be mobile and related with anthropogenic pollution. The degree of metal pollution and potential toxicity of sediments were higher in the lower reaches of both rivers. The metal speciation in sediments had a bimodal distribution over particle-size fractions. Heavy metals were subject to accumulation in the silt/clay fraction (< 25 microm) and coarse sand (420-2,000 microm). By normalizing the sum of the exchangeable, carbonate-bound, and Fe/Mn oxide-bound metals, it suggested that the potential toxicity to the aquatic ecosystem was caused by the fine sediments as well as coarse sediments.

Effects of ferric ion on bioleaching of heavy metals from contaminated sediment

Bioleaching is one of the promising procedures for removal of heavy metals from contaminated sediments. The advantages of this biotechnology are that it is easy, efficient, less costly and friendly to the environment. However, the principal disadvantage of this process is its slow kinetics in metal solubilization, which may limit practical application of the bioleaching process. In order to enhance the rate and efficiency of metal solubilization, the ferric ion was used as a catalytic agent in the bioleaching process. It was found that the sediment pH apparently decreased in the bioleaching after addition of ferric ion. The metal solubilization increased quickly after the addition of ferric ion. The rate of metal solubilization was enhanced by the addition of ferric ion, especially for Cr and Pb. An increase in the amount of ferric ion added increased the final efficiency of metal solubilization. The highest final efficiency of metal solubilization was obtained in the bioleaching with 1 g/L of ferric ion. Besides, the growth of sulfur-oxidizing bacteria was not affected by addition of ferric ion in the bioleaching. It was concluded that the kinetics of metal solubilization were enhanced by addition of ferric ion in the bioleaching process.