Pyroptotic macrophages induce disruption of glutamate metabolism in periodontal ligament stem cells contributing to their compromised osteogenic potential.

Macrophage pyroptosis is of key importance to host defence against pathogen infections and may participate in the progression and recovery of periodontitis. However, the role of pyroptotic macrophages in regulating periodontal ligament stem cells (PDLSCs), the main cell source for periodontium renewal, remains unclear. First, we found that macrophage pyroptosis were enriched in gingiva tissues from periodontitis patients compared with those of healthy people through immunofluorescence. Then the effects of pyroptotic macrophages on the PDLSC osteogenic differentiation were investigated in a conditioned medium (CM)-based coculture system in vitro. CM derived from pyroptotic macrophages inhibited the osteogenic differentiation-related gene and protein levels, ALP activity and mineralized nodule formation of PDLSCs. The osteogenic inhibition of CM was alleviated when pyroptosis was inhibited by VX765. Further, untargeted metabolomics showed that glutamate limitation may be the underlying mechanism. However, exogenous glutamate supplementation aggravated the CM-inhibited osteogenic differentiation of PDLSCs. Moreover, CM increased extracellular glutamate and decreased intracellular glutamate levels of PDLSCs, and enhanced the gene and protein expression levels of system xc - (a cystine/glutamate antiporter). After adding cystine to CM-based incubation, the compromised osteogenic potency of PDLSCs was rescued. Our data suggest that macrophage pyroptosis is related to the inflammatory lesions of periodontitis. Either pharmacological inhibition of macrophage pyroptosis or nutritional supplements to PDLSCs, can rescue the compromised osteogenic potency caused by pyroptotic macrophages.

Harnessing Mechanical Stress with Viscoelastic Biomaterials for Periodontal Ligament Regeneration.

The viscoelasticity of mechanically sensitive tissues such as periodontal ligaments (PDLs) is key in maintaining mechanical homeostasis. Unfortunately, PDLs easily lose viscoelasticity (e.g., stress relaxation) during periodontitis or dental trauma, which disrupt cell-extracellular matrix (ECM) interactions and accelerates tissue damage. Here, Pluronic F127 diacrylate (F127DA) hydrogels with PDL-matched stress relaxation rates and high elastic moduli are developed. The hydrogel viscoelasticity is modulated without chemical cross-linking by controlling precursor concentrations. Under cytomechanical loading, F127DA hydrogels with fast relaxation rates significantly improved the fibrogenic differentiation potential of PDL stem cells (PDLSCs), while cells cultured on F127DA hydrogels with various stress relaxation rates exhibited similar fibrogenic differentiation potentials with limited cell spreading and traction forces under static conditions. Mechanically, faster-relaxing F127DA hydrogels leveraged cytomechanical loading to activate PDLSC mechanotransduction by upregulating integrin-focal adhesion kinase pathway and thus cytoskeletal rearrangement, reinforcing cell-ECM interactions. In vivo experiments confirm that faster-relaxing F127DA hydrogels significantly promoted PDL repair and reduced abnormal healing (e.g., root resorption and ankyloses) in delayed replantation of avulsed teeth. This study firstly investigated how matrix nonlinear viscoelasticity influences the fibrogenesis of PDLSCs under mechanical stimuli, and it reveals the underlying mechanobiology, which suggests novel strategies for PDL regeneration.

Microbial transformation of artemisinin and its derivatives / 中国中药杂志

Microbial transformation is an efficient enzymatic approach for the structural modification of exogenous compounds to obtain derivatives. Compared with traditional chemical synthesis, the microbial transformation has in fact the undoubtable advantages of strong region-and stereo-selectivity, and a low environmental and economic impact on the production process, which can achieve the reactions challenging to chemical synthesis. Because microbes are equipped with a broad-spectrum of enzymes and therefore can metabolize various substrates, they are not only a significant route for obtaining novel active derivatives, but also an effective tool for mimicking mammal metabolism in vitro. Artemisinin, a sesquiterpene with a peroxy-bridged structure serving as the main active functional group, is a famous antimalarial agent discovered from Artemisia annua L. Some sesquiterpenoids, such as dihydroartemisinin, artemether, and arteether, have been developed on the basis of artemisinin, which have been successfully marketed and become the first-line antimalarial drugs recommended by WHO. As revealed by pharmacological studies, artemisinin and its derivatives have exhibited extensive biological activities, including antimalarial, antitumor, antiviral, anti-inflammatory, and immunomodulatory. As an efficient approach for structural modification, microbial transformation of artemisinin and its derivatives is an increasingly popular strategy that attracts considerable attention recently, and numerous novel derivatives have been discovered. Herein, this paper reviewed the microbial transformation of artemisinin and its artemisinin, including microbial strains, culture conditions, product isolation and yield, and biological activities, and summarized the advances in microbial transformation in obtaining active derivatives of artemisinin and the simulation of in vivo metabolism of drugs.

Tracking of Stem Cells from Human Exfoliated Deciduous Teeth Labeled with Molday ION Rhodamine-B during Periodontal Bone Regeneration in Rats

Background and Objectives@#Chronic periodontitis can lead to alveolar bone resorption and eventually tooth loss. Stem cells from exfoliated deciduous teeth (SHED) are appropriate bone regeneration seed cells. To track the survival, migration, and differentiation of the transplanted SHED, we used super paramagnetic iron oxide particles (SPIO) Molday ION Rhodamine-B (MIRB) to label and monitor the transplanted cells while repairing periodontal bone defects. @*Methods@#and Results: We determined an appropriate dose of MIRB for labeling SHED by examining the growth and osteogenic differentiation of labeled SHED. Finally, SHED was labeled with 25 μg Fe/ml MIRB before being transplanted into rats. Magnetic resonance imaging was used to track SHED survival and migration in vivo due to a low-intensity signal artifact caused by MIRB. HE and immunohistochemical analyses revealed that both MIRB-labeled and unlabeled SHED could promote periodontal bone regeneration. The colocalization of hNUC and MIRB demonstrated that SHED transplanted into rats could survive in vivo. Furthermore, some MIRB-positive cells expressed the osteoblast and osteocyte markers OCN and DMP1, respectively. Enzyme-linked immunosorbent assay revealed that SHED could secrete protein factors, such as IGF-1, OCN, ALP, IL-4, VEGF, and bFGF, which promote bone regeneration. Immunofluorescence staining revealed that the transplanted SHED was surrounded by a large number of host-derived Runx2- and Col II-positive cells that played important roles in the bone healing process. @*Conclusions@#SHED could promote periodontal bone regeneration in rats, and the survival of SHED could be tracked in vivo by labeling them with MIRB. SHED are likely to promote bone healing through both direct differentiation and paracrine mechanisms.

Roles of extracellular vesicles in periodontal homeostasis and their therapeutic potential.

Periodontal tissue is a highly dynamic and frequently stimulated area where homeostasis is easily destroyed, leading to proinflammatory periodontal diseases. Bacteria-bacteria and cell-bacteria interactions play pivotal roles in periodontal homeostasis and disease progression. Several reviews have comprehensively summarized the roles of bacteria and stem cells in periodontal homeostasis. However, they did not describe the roles of extracellular vesicles (EVs) from bacteria and cells. As communication mediators evolutionarily conserved from bacteria to eukaryotic cells, EVs secreted by bacteria or cells can mediate interactions between bacteria and their hosts, thereby offering great promise for the maintenance of periodontal homeostasis. This review offers an overview of EV biogenesis, the effects of EVs on periodontal homeostasis, and recent advances in EV-based periodontal regenerative strategies. Specifically, we document the pathogenic roles of bacteria-derived EVs (BEVs) in periodontal dyshomeostasis, focusing on plaque biofilm formation, immune evasion, inflammatory pathway activation and tissue destruction. Moreover, we summarize recent advancements in cell-derived EVs (CEVs) in periodontal homeostasis, emphasizing the multifunctional biological effects of CEVs on periodontal tissue regeneration. Finally, we discuss future challenges and practical perspectives for the clinical translation of EV-based therapies for periodontitis.

The fate of flavonoids after oral administration: a comprehensive overview of its bioavailability.

Despite advancements in synthetic chemistry, nature remains the primary source of drug discovery, and this never-ending task of finding novel and active drug molecules will continue. Flavonoids have been shown to possess highly significant therapeutic activities such as anti-inflammatory, anti-oxidant, anti-viral, anti-diabetic, anti-cancer, anti-aging, neuroprotective, and cardioprotective, etc., However, it has been found that orally administered flavonoids have a critical absorption disorder and, therefore, have low bioavailability and show fluctuating pharmacokinetic and pharmacodynamic responses. A detailed investigation is required to assess and analyze the variation in the bioavailability of flavonoids due to interactions with the intestinal barrier. This review will emphasize on the bioavailability and the pharmacological applications of flavonoids, key factors affecting their bioavailability, and strategies for enhancing bioavailability, which may lead to deeper understanding of the extent of flavonoids as a treatment and/or prevention for different diseases in clinics.

Analysis of risk factors and construction of risk prediction model of cognitive dysfunction in patients with atrial fibrillation / 中国实用护理杂志

Objective:To identify the risk factors of cognitive dysfunction in patients with atrial fibrillation and to establish a risk prediction model.Methods:The convenience sampling method was used to evaluate 260 patients with atrial fibrillation who were hospitalized in the Department of Cardiology of the Affiliated Hospital of Jining Medical College from January to December 2020. The cognitive function of the patients was evaluated with the Montreal Cognitive Function Assessment Scale (MoCA). Univariate analysis was used to screen the independent variables that had influence on the occurrence of cognitive dysfunction, and the statistically significant variables were included in the multivariate Logistic regression model. According to the regression coefficients of statistically significant variables, a line map was drawn to construct the risk prediction model of cognitive dysfunction in patients with atrial fibrillation.Results:There were 209 cases with cognitive impairment and 51 cases without cognitive impairment. Univariate analysis showed that sex, age, smoking history, drinking history, education level, free thyroxine, hemoglobin, D-dimer and BMI ( χ2 values were 4.08-18.83, t values were -6.04-2.94, Z=-2.76) were significantly different between the patients with or without cognitive dysfunction. The results of multivariate Logistic regression analysis showed that age ( OR values were 1.13), education level ( OR=0.01-0.05), quit smoking history ( OR=0.36), drinking history ( OR=0.35) and free thyroxine( OR=1.14) had significantly statistical significance ( P<0.05). The area under ROC curve (AUC) = 0.878 and AUC>0.8, this model had good clinical prediction ability. Conclusions:The construction of cognitive dysfunction risk prediction model for patients with atrial fibrillation can prevent or intervene high risk factors in advance, facilitate clinical use, and provide data support for the improvement of cognitive function in patients with atrial fibrillation.

MicroRNA-Triggered Deconstruction of Field-Free Spherical Nucleic Acid as an Electrochemiluminescence Biosensing Switch.

Herein, a new field-free and highly ordered spherical nucleic acid (SNA) nanostructure was self-assembled directly by ferrocene (Fc)-labeled DNA tweezers and DNA linkers based on the Watson-Crick base pairing rule, which was employed as an electrochemiluminescence (ECL) quenching switch with improved recognition efficiency due to the high local concentration of the ordered nanostructure. Moreover, with a collaborative strategy combined with the advantages of both self-accelerated approach and pore confinement-enhanced ECL effect, the mesoporous silica nanospheres (mSiO2 NSs) were prepared to be filled with rubrene (Rub) as ECL emitters and Pt nanoparticles (PtNPs) as coreaction accelerators (Rub-Pt@mSiO2 NSs), which demonstrated high ECL response in the aqueous media (dissolved O2 as coreactant). When the SNA nanostructure was immobilized on the Rub-Pt@mSiO2 NSs-modified electrode, it presented a "signal off" state owing to the quenching effect of the Fc molecules. As a proof of concept, the SNA-based ECL switch platform was applied in the detection of microRNA let-7b (let-7b). Impressively, in the presence of the target let-7b, a deconstruction of the SNA nanostructure was actuated, causing the Fc to leave the electrode surface and achieved an extremely high ECL recovery ("signal on" state). Hence, a sensitive determination for let-7b was realized with a low detection limit of 1.8 aM ranging from 10 aM to 1 nM by employing the Rub-Pt@mSiO2 NSs-based ECL platform combined with the target-triggered SNA deconstruction, which also offered an ingenious method for the further applications of biomarker analyses.

Protective effect of astragaloside on renal injury induced by radiation through toll-like receptor 4/nuclear factor kappa B pathway / 解剖学报

Objective To explore whether astragaloside IV (AS-IV) can protect radiation-induced kidney injury through toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB)-mediated signaling pathway. Methods The mice were randomly divided into normal control group, DMSO solvent group, irradiation group (IR), IR + AS-IV 20 mg/kg group and IR + AS-IV 40 mg/kg group. One month after intraperitoneal injection of AS-IV, the mice were irradiated with 8 Gy 60Coγ and to the content of serum creatinine (Cr) and uric acid (BUA) in serum were determined, HE and immunohistochemical staining, and expression of TLR4/NF-κB signaling pathway related protein in kidney were performed. Results Compared with the control group, the levels of Cr and BUA in the serum of the radiation group increased significantly (P<0.001), glomerular atrophy and tubular expansion, TLR4 and myeloid differentiation factor 88(MyD88) positive expression increased significantly (P< 0.001), and the expression of TLR4/NF-κB signaling pathway-related proteins[ TLR4, MyD88, NF-κB, interleukin-1 β (IL-Iβ), tumor necrosis factor α (TNF-α)] increased significantly (P< 0.01); AS-IV pretreatment can reduce the content of Cr and BUA in serum (P<0.05, P<0.01 or P<0.001), significantly improve the pathological response caused by radiation, and reduce the expression of TLR4/NF-κB signaling pathway-related proteins (P<0.05 or P<0.01). Conclusion AS-IV may down-regulate the release of inflammatory factors through the TLR4/NF-κB signaling pathway, thereby improving radiation-induced kidney injury in mice and playing a protective role.

Prediction of Q-markers of Citri Reticulatae Pericarpium volatile oil and GC-MS based quantitative analysis / 中国中药杂志

This study was designed to predict the Q-markers of Citri Reticulatae Pericarpium volatile oil and conduct quantitative analysis by GC-MS. The common components of Citri Reticulatae Pericarpium volatile oil were detected by GC-MS. The network pharmacology approaches were utilized for constructing the component-target network and protein-protein interaction(PPI) network, followed by the GO and KEGG pathway enrichment analysis to clarify the pharmacological effects of common components. Molecular docking was conducted to observe the biological activities of common components, thus identifying the Q-markers of Citri Reticulatae Pericarpium volatile oil. The obtained Q-markers were subjected to quantitative analysis by GC-MS. The GC-MS analysis of 19 batches of Citri Reticulatae Pericarpium volatile oil revealed three common components, namely, D-limonene, γ-terpinene, and myrcene. The common components were analyzed based on network pharmacology, and the results showed that Citri Reticulatae Pericarpium volatile oil mainly acted on the core targets GABRA1, GABRA6, GABRA5, GABRA3, and GABRA2 through D-limonene and γ-terpinene, with five important pathways such as nicotine addiction and GABAergic synapse involved. The core targets were mainly distributed in olfactory region, cerebral cortex, cerebellum, basal ganglia, hippocampus, and amygdala to exert the pharmacological effects. As revealed by molecular docking, D-limonene and γ-terpinene exhibited good biological activities, so they were identified as the Q-markers of Citri Reticulatae Pericarpium volatile oil. The results of quantitative analysis showed that the volume fraction of D-limonene was within the range of 0.77-1.03 μL·mL~(-1), and that of γ-terpinene within the range of 0.04-0.13 μL·mL~(-1). The prediction of D-limonene and γ-terpinene as the Q-markers of Citri Reticulatae Pericarpium volatile oil has laid an experimental foundation for the establishment of the quality evaluation standard for Citri Reticulatae Pericarpium volatile oil.

Association between childhood maltreatment and suicide among rural adolescents / 中国学校卫生

Objective@#This study explored the relationship between childhood maltreatment and adolescent suicide provides a scientific basis for suicide prevention strategies.@*Methods@#A total of 16 271 middle and high school students from rural areas in Anhui, Guangdong, Yunnan, Heilongjiang and Hubei provinces were enrolled through multi stage stratified cluster random sampling. Structured questionnaires were used to collect information on participants general information, childhood neglect, abuse, suicide ideation, suicide plans and suicide attempts in the 12 months prior to the survey. Multivariate Logistic regression models were used to analyze the associations of childhood neglect and childhood maltreatment with suicide ideation, suicide plans and suicide attempts.@*Results@#The number of suicide ideations, suicide plans and suicide attempts among rural adolescents were 2 453( 15.1 %), 1 164(7.2%) and 572(3.5%), respectively. The number of cases of childhood neglect, moderate physical abuse and severe physical abuse were 10 756(66.1%), 4 311(26.5%) and 703(4.3%), respectively. Univariate analysis showed that childhood neglect and abuse were significantly associated with suicide ideation, suicide plans and suicide attempts( P <0.05). After controlling for age, gender, only children, parental education level, income, emotional management and social support, childhood neglect and abuse remained significantly correlated with suicide ideation, suicide plans and suicide attempts( OR =1.62-5.14, P <0.05); the OR(OR 95%CI) for severe physical abuse were 3.00(2.49-3.62), 3.52(2.81-4.40),5.14(3.87-6.83) respectively.@*Conclusion@#Childhood neglect and abuse may increase the risk of suicide among adolescents in rural China, and effective measures should be taken to reduce childhood neglect and abuse and prevent suicide.

State-by-State prediction of likely COVID-19 scenarios in the United States and assessment of the role of testing and control measures

Due to the heterogeneity among the States in the US, predicting COVID-19 trends and quantitatively assessing the effects of government testing capability and control measures need to be done via a State-by-State approach. We develop a comprehensive model for COVID-19 incorporating time delays and population movements. With key parameter values determined by empirical data, the model enables the most likely epidemic scenarios to be predicted for each State, which are indicative of whether testing services and control measures are vigorous enough to contain the disease. We find that government control measures play a more important role than testing in suppressing the epidemic. The vast disparities in the epidemic trends among the States imply the need for long-term placement of control measures to fully contain COVID-19.

A study on resection extent for medullary thyroid carcinoma / 中华普通外科杂志

Objective:To analyze the relationship between surgical resection range and prognosis of medullary thyroid carcinoma.Methods:Clinical data of 39 patients with medullary thyroid carcinoma treated in Shanghai Sixth People′s Hospital from Jan 2017 to Mar 2020 were retrospectively analyzed.Results:There were 13 males and 26 females, age ranging from 26 to 72 years old. Preoperative calcitonin levels increased from 21.5 to 20 000 ng/L. Tumor stage: stage Ⅰ was 35.9%, stage Ⅱ 23.1%, stage Ⅲ 25.6%, stage Ⅳ 15.4%. The proportion of lymph node metastasis in central region was 53.8% (21/39). The proportion of lateral cervical lymph node metastasis was 43.6% (17/39), which was statistically related with the preoperative calcitonin level ≥200 ng/L. The median follow-up was 10 months, and the biochemical and anatomical cure rates were 66.7% and 33.3% respectively. Transient recurrent laryngeal nerve palsy, temporary and permanent hypothyroidism were 2.6%, 23% and 2.6%, respectively. There was no postoperative hemorrhage, infection, lymphatic leak or death.Conclusions:Bilateral total thyroidectomy, and at least ispilateral central lymph node dissection were advocated for patients with MTC. When preoperative calcitonin level ≥200 ng/L, lateral cervical lymph node dissection is advised.

Advances in studies on structure and pharmacological activities of natural tirucallane-type triterpenoids / 中国中药杂志

The tirucallane-type triterpenoids, composed of six isoprene units, belong to a group of tetracyclic triterpenoids. Although the naturally-derived tirucallane-type triterpenoids were found in a small amount, the kind of compounds showed various structures, which consist of apo-type, linear said-chain-type and cyclolike said-chain-type and broad bioactivities, such as cytotoxicity, anti-inflammation, antioxidation and anti-plasmin, etc. This paper summarized origins, structures and bioactivities of tirucallane-type triterpenoids in recent ten years. The future research and exploration of tirucallane-type triterpenoids were discussed and prospected.

Reviews on natural monocyclic sesquiterpenoids and their bioactivities / 中国中药杂志

Sesquiterpenes are a class of terpenoids composed of three isoprene units( 15 carbons). Sesquiterpenoids possess a variety of different structures,including acyclic sesquiterpenes,monocyclic sesquiterpenoids,bicyclic sesquiterpenoids,tricyclic sesquiterpenoids,tetracyclic sesquiterpenoids and macrocyclic sesquiterpenoids. Among them,a large number of monocyclic sesquiterpenoids were isolated and display extensive bioactivities,such as cytotoxic,antioxidant,anti-inflammatory,antibacterial and other activities. In this review,we summarized the progress about the phytochemistry and biological activities of monocyclic sesquiterpenoids( a total of161 compounds) reported from 2014 to 2018( 5 years),including megastigmanes,monocyclofarnesol-type,bisabolane-type,germacrane-type,and other types of monocyclic sesquiterpenoids. Furthermore,several future research perspectives and development of sesquiterpenoids as potential therapeutic agents were discussed as well.

Nickel-catalyzed difunctionalization of allyl moieties using organoboronic acids and halides with divergent regioselectivities.

Efficient difunctionalization of alkenes allows the rapid construction of molecular complexity from simple building blocks in organic synthesis. We present herein a nickel-catalyzed dicarbofunctionalization of alkenes using readily available organoboronic acids and organic halides in a three-component fashion. In particular, an unprecedented regioselectivity of the 1,3-dicarbofunctionalization of N-allylpyrimidin-2-amine is achieved when aryl and methyl iodides are utilized. In contrast, the use of alkyl bromides with ß-hydrogens results in 1,3-hydroarylation or oxidative 1,3-diarylation. Preliminary mechanistic studies suggest an isomerization involving nickel hydride in the 1,3-difunctionalization reactions. On the other hand, the use of alkenyl or alkynyl halides promotes alternative regioselectivities to deliver 1,2-alkenylcarbonation or intriguing 2,1-alkynylcarbonation products. Such 2,1-alkynylarylation is also applicable to N-allylbenzamide as a different class of substrates. Overall, this nickel-catalyzed process proves to be powerful in delivering versatile difunctionalized compounds using readily available reagents/catalysts and a simple procedure.

A study on the preparation and application of a core-shell surface imprinted uranyl magnetic chelating adsorbent.

A core-shell surface imprinted uranyl magnetic chelating adsorbent (UMCA) was synthesized by combining the sol-gel process with the surface molecular imprinting technique (SMIT). A specific salophen and uranyl-salophen were designed and synthesized. Then, the synthesized uranyl-salophen complex was used as a template (in which uranyl is the target analyte), 3-aminopropyltriethoxysilane as a functional monomer and tetraethylorthosilicate as a cross-linker. The obtained UMCA was characterized by a variety of modern analytical and detection techniques. The adsorbent can be used for the solid-phase extraction of uranyl with good selectivity, high adsorption capacity, magnetic separation characteristics and good reusability. The chelating sorbent was successfully applied for the separation of uranyl, followed by multiphase photocatalytic resonance fluorescence method determination in several environmental water samples with a relative standard deviation of <5.48% and spiked recoveries of 92.5% to 103.0%. The adsorption mechanism was preliminarily discussed.

Evaluation of the reliability and validity of Chinese-version Good Death Inventory among oncology nurse specialist / 中国实用护理杂志

Objective@#To evaluate the reliability and validity of Chinese-version Good Death Inventory among oncology nurse specialists.@*Methods@#A further revision has been made in the Chinese-version Good Death Inventory from Taiwan experts through expert review and preliminary experiment. The reliability and validity of the Chinese-version GDI was evaluated among 180 oncology nurse specialists.@*Results@#The Chinese-version of GDI was easy to understand. Most respondents finished the whole scale in 25 minutes and the valid response rate of the scale was100%. The I-CVI value of each item was 0.67-1.00, S-CVI/Ave was 0.938. KMO was 0.832, and the revised Chinese-version GDI consisted of 54 items in 18 dimensions (Core 10 Domains and Optional 8 Domains). The total scale′ s Cronbach′ s alpha coefficient was 0.950, split-half reliability coefficient was 0.832. Cronbach′ s alpha of Core 10 Domains was 0.938 and that of Optional 8 Domains was 0.876.@*Conclusions@#The Chinese-version GDI is a valid scale to measure end-of-life care comprehensive outcomes from Chinese oncology nurse specialists′ perspective.

Constituents isolated from n-butanol extract of leaves of Moringa oleifera / 中国中药杂志

Seventeen compounds were isolated from n-butanol extract of the leaves of Moringa oleifera, using column chromatography over macroporous resin HP-20,Sephadex LH-20, and ODS. Their structures were identified as two carboline,tangutorid E(1) and tangutorid F(2); three phenolic glycosides,niazirin(3)，benzaldehyde 4-O-α-L-rhamnopyranoside(4) and 4-O-β-D-glucopyranosidebenzoic acid(5); four chlorogenic acid and derivatives,4-caffeoylquinic acid(6),methyl 4-caffeoylquinate(7),caffeoylquinic acid(8) and methyl caffeoylquinate(9); two nucleosids,uridine(10) and adenosine(11); one flavone,quercetin 3-O-β-D-glucopyranoside(12); five other types of compounds,phthalimidineacetic acid(13),3-pyridinecarboxamide(14),3,4-dihydroxy-benzoic acid(15),5-hydroxymethyl-2-furancarboxylic acid(16) and 5-hydroxymethyl-2-furaldehyde(17) by the spectral data of ¹H, ¹³C-NMR and MS. Among them,compounds 1-2,7,9-10,16 and 17 were isolated from M. oleifera for the first time.

Determination of Six Heavy Metals in Iron Filings and Ferric Ammonium Citrate by Atomic Absorption Spectrophotometry / 中国药师

Objective:To establish an atomic absorption spectrophotometric method for the determination of 6 heavy elements in-cluding lead,cadmium,mercury, arsenic, copper and chromium in iron filings and ferric ammonium citrate in order to control the quality and ensure people's daily medicine safety.Methods:The determination method for lead,cadmium,chromium,copper,arse-nic and mercury was a graphite furnace method, a graphite furnace method, a graphite furnace method, a flame method, a hydride method and a cold steam absorption method,respectively. Results:The concentration of lead within the range of 0-50 ng·ml-1had a good linear relationship with the absorbance(r=0.999 8),and the average recovery was 98.9%(RSD=2.3%,n=6). The concen-tration of cadmium within the range of 0-4 ng·ml-1had a good linear relationship with the absorbance(r=0.999 1),and the average recovery was 90.5%(RSD=1.5%,n=6). The concentration of chromium within the range of 0-50 ng·ml-1had a good linear rela-tionship with the absorbance(r=0.999 7),and the average recovery was 96.1%(RSD=1.1%,n=6). The concentration of copper within the range of 0-800 ng·ml-1had a ood linear relationship with the absorbance (r=0.999 9), and the average recovery was 97.5%(RSD=1.2%,n=6). The concentration of arsenic within the range of 0-16 ng·ml-1had a good linear relationship with the absorbance (r=0.999 0),and the average recovery was 93.4%(RSD =1.1%, n =6). The concentration of mercury within the range of 0-18 ng·ml-1had a good linear relationship with the absorbance(r=0.999 2),and the average recovery was 93.2%(RSD=3.8%,n=6). Conclusion:The method with good repeatability is accurate,which can be used for the quality control of iron filings and ferric ammonium citrate.