Unveiling the Chemical Composition of Sulfur-Fumigated Herbs: A Triple Synthesis Approach Using UHPLC-LTQ-Orbitrap MS-A Case Study on Steroidal Saponins in Ophiopogonis Radix

Ophiopogonis Radix (OR) is a traditional Chinese medicine. In recent years, in order to achieve the purpose of drying, bleaching, sterilizing and being antiseptic, improving appearance, and easy storage, people often use sulfur fumigation for its processing. However, changes in the chemical composition of medicinal herbs caused by sulfur fumigation can lead to the transformation and loss of potent substances. Therefore, the development of methods to rapidly reveal the chemical transformation of medicinal herbs induced by sulfur fumigation can guarantee the safe clinical use of medicines. In this study, a combined full scan-parent ions list-dynamic exclusion acquisition-diagnostic product ions analysis strategy based on UHPLC-LTQ-Orbitrap MS was proposed for the analysis of steroidal saponins and their transformed components in sulfur-fumigated Ophiopogonis Radix (SF-OR). Based on precise mass measurements, chromatographic behavior, neutral loss ions, and diagnostic product ions, 286 constituents were screened and identified from SF-OR, including 191 steroidal saponins and 95 sulfur-containing derivatives (sulfates or sulfites). The results indicated that the established strategy was a valuable and effective analytical tool for comprehensively characterizing the material basis of SF-OR, and also provided a basis for potential chemical changes in other sulfur-fumigated herbs.

Chemical analysis of the Chinese herbal medicine licorice (Gan-Cao): An update review

ETHNOPHARMACOLOGICAL RELEVANCE

Licorice, called Gan-Cao in China, is one of the most popular traditional herbal medicines. It is derived from the dried roots and rhizomes of Glycyrrhiza uralensis, G. glabra, and G. inflata. Licorice is recorded in the pharmacopoeias of China, Japan, US, and Europe.

AIM

This review updates research progress of licorice from the perspectives of chemical analysis, quality evaluation, drug metabolism, and pharmacokinetic studies from 2009 to April 2022.

MATERIALS AND METHODS

Both English and Chinese literatures were collected from databases including PubMed, Elsevier, Web of Science, and CNKI (Chinese). Licorice, extraction, structural characterization/identification, quality control, metabolism, and pharmacokinetics were used as keywords.

RESULTS

Newly developed analytical methods, including LC/UV, 2DLC, LC/MS, GC/MS, and mass spectrometry imaging (MSI) for chemical analysis of licorice were summarized.

CONCLUSION

This review provides a comprehensive summary on chemical analysis of licorice.

Characterization of prenylated phenolics in Glycyrrhiza uralensis by offline two-dimensional liquid chromatography/mass spectrometry coupled with mass defect filter

Prenylated phenolics are an important class of natural products. In this study, an efficient strategy was established to systematically characterize the prenylated phenolics in Glycyrrhiza uralensis, a popular herbal medicine. Firstly, offline two-dimensional liquid chromatography/mass spectrometry (2DLC/MS) coupled with mass defect filter (MDF) technology was used to preliminarily detect 1631 potential prenylated phenolics. Secondly, the tandem mass spectrometry fragmentation features of different types of prenylated phenolics were investigated using 29 reference standards. Diagnostic fragmentations included neutral loss (NL) of 42 Da for the annular type and NL of 56 Da for the catenulate type in the positive ion mode, and NL of 56 Da for A-ring prenyl groups and NL of 69 Da for B-ring prenyl groups in the negative ion mode. As a result, the prenylation types, substitution sites, and adjacent OH and OCH₃ substitutions of 320 prenylated phenolics in G. uralensis were rapidly characterized. Moreover, three prenylated dihydrostilbenes were purified from the aerial part of G. uralensis to verify the structural characterizations.

Comparative bioactivity evaluation and chemical profiling of different parts of the medicinal plant Glycyrrhiza uralensis

Glycyrrhiza uralensis is a popular medicinal plant worldwide. Its roots and rhizomes are used as the traditional Chinese medicine Gan-Cao. However, little is known on medicinal potential and chemistry of the other parts of the plant. In this work, the biological activities and chemical components of the roots, stems, leaves, and seeds of G. uralensis were investigated comparatively. The four parts exhibited different but noticeable biological activities. The chemicals in the four parts were globally characterized by liquid chromatography coupled with mass spectrometry (LC/MS) on a Thermo Vanquish UHPLC system connected to a Q-Exactive quadrupole Orbitrap mass spectrometer. By integrating molecular networking, compound spectral matching, MS2LDA-based substructure recognition, and reference standards comparison, a total of 1301 compounds were rapidly characterized. Three flavonoid C-glycosides were purified and their structures were identified by NMR spectroscopic analysis. Orthogonal partial least squares-discriminate analysis (OPLS-DA) further revealed 196 differential chemicals for the four parts. This work will promote the medicinal resource utilization of G. uralensis.

Chemical Variations among Shengmaisan-Based TCM Patent Drugs by Ultra-High Performance Liquid Chromatography Coupled with Hybrid Quadrupole Orbitrap Mass Spectrometry

Shengmaisan (SMS) is a famous traditional Chinese medicine (TCM) formula to treat coronary heart diseases. It has been developed into several TCM patent drugs to meet the demands of different patients. In this study, a research strategy was proposed to reveal the chemical variations among four SMS-based patent drugs, including Shengmai Oral Solution (Shengmaiyin, SMY), Shengmai Capsule (Shengmai Jiaonang, SMJN), Yiqi Fumai Injection (YQFMI), and Yiqi Fumai Capsule (Yiqi Fumai Jiaonang, YQJN). Firstly, 227 compounds were tentatively identified using an Orbitrap-MS in the full scan/dd-MS2 mode. Secondly, untargeted metabolomics analysis suggested that ginsenosides, steroidal saponins, and lignans were the main types of differential compounds for the four patent drugs. Finally, the contents of 25 compounds were simultaneously determined in 30 batches of samples in the parallel reaction monitoring (PRM) mode. Partial least squares discriminant analysis (PLS-DA) revealed the contents of ginsenosides Re, Rg1, Rb1, Ro, and Rg3, and schisandrin showed the highest intergroup variations. These compounds were chemical markers to differentiate the SMS-based patent drugs.

Discovery of minor quality evaluation marker compounds for Chinese patent medicine products using a two-leveled metabolomics strategy

Chinese patent medicines (CPMs) are popularly used in clinical practice. Though the composition is complex, the quality of CPM is usually evaluated by the contents of a few main compounds. In this study, a two-leveled metabolomics strategy was proposed to discover minor marker compounds for different CPM products. Zhenqi Fuzheng (ZQFZ) granule was studied an example, where 15 batches from 3 producers were analyzed. The samples were separated using UHPLC on an Acquity UPLC® HSS T3 column, and then detected using Q-Orbitrap-MS. In the first level, 1475 common peaks were extracted and 95 compounds were identified using diagnostic ions and a homemade database. In the second level, the data were subjected to a two-way hierarchical clustering analysis and screened by variable importance value. In total 14 marker compounds were discovered which were responsible for the grouping of different ZQFZ products. Echinacoside (22), oleoside (13), loganic acid (5), salidroside (7), ligustrosidic acid (42), 6α-hydroxygeniposide (28), and oleoside 11-methyl ester (15) could be used to reflect the quality difference for ZQFZ granule products. The proposed strategy could also contribute to the discovery of quality control markers for other CPMs.

A global profiling strategy using comprehensive two-dimensional liquid chromatography coupled with dual-mass spectrometry platforms: Chemical analysis of a multi-herb Chinese medicine formula as a case study

Although ultraviolet detector or mass spectrometer could be coupled with two-dimensional liquid chromatography (2DLC) to analyze complex constituents, full detection and identification of the compounds are difficult. Suffering from biased UV detection and insufficient MS data interpretation, a number of minor compounds are neglected though they are separated. In this study, we report a global chemical profiling strategy using comprehensive 2DLC coupled with dual-MS platforms, including Orbitrap-MS and QqQ-MS. It was exemplified by an 11-herb Chinese medicine formula Xiaoer-Feire-Kechuan (XFK). Firstly, constituents in XFK were separated on a CSH C₁₈ × Phenyl-Hexyl 2DLC system with a practical peak capacity of 990.5 and an orthogonality of 90.3%. Secondly, untargeted mass spectral data was collected using dd-MS² scan on an Orbitrap-MS. In total 542 peaks were detected, which was 4 times of that detected by 2DLC/UV (131 peaks). A total of 108 compounds were tentatively identified. Thirdly, targeted mass spectral data was collected for 8 characteristic substructures using neutral loss and precursor ion (NL/PRE) scan on a QqQ-MS. Extracted ion chromatogram was used to recognize minor constituents. An additional of 151 compounds were detected. Our study indicated that comprehensive 2DLC coupled with dd-MS² and NL/PRE-MS is a powerful technique for the global profiling of multi-component systems.

Simultaneous determination of 35 constituents and elucidation of effective constituents in a multi-herb Chinese medicine formula Xiaoer-Feire-Kechuan

Xiaoer-Feire-Kechuan (XFK) is an 11-herb Chinese medicine formula to treat cough and pulmonary inflammation. The complicated composition rendered its chemical analysis and effective-component elucidation. In this study, we combined quantitative analysis and bioactivity test to reveal the anti-inflammatory constituents of XFK. First, UPLC-DAD and UHPLC/Q-Orbitrap-MS methods were established and validated to quantify 35 analytes (covering 9 out of 11 herbs) in different XFK formulations. Parallel reaction monitoring mode built in Q-Orbitrap-MS was used to improve the sensitivity and selectivity. Then, anti-inflammatory activities of the 35 analytes were analyzed using in vitro COX-2 inhibition assay. Finally, major analytes forsythosides H, I, A (8–10), and baicalin (15) (total contents varied from 21.79 to 91.20 mg/dose in different formulations) with significant activities (inhibitory rate ≥ 80%) were proposed as the anti-inflammatory constituents of XFK. The present study provided an effective strategy to discover effective constituents of multi-herb formulas.

∙

Effective components were elucidated for XFK, a 11-herb formula.

∙Contents of 35 compounds were determined using UPLC-DAD and UHPLC/Q-Orbitrap-MS.

∙Parallel Reaction Monitoring mode was used to improve the sensitivity.

∙COX-2 inhibition assay was used to evaluate the bioactivity of 35 compounds.

∙Five major compounds were proposed as anti-inflammatory constituents for XFK.

Design of super-strong and thermally stable nanotwinned Al alloys via solute synergy

Al alloys have widespread industrial applications. However, their mechanical strength is often much lower than steels. Here, we investigate the influence of solutes on achieving ultrahigh strength and thermal stability of nanotwinned Al alloys. In situ micropillar compression tests show the addition of a small amount of Ti can significantly increase the mechanical strength of Al-Ni alloys to 2 GPa. Deformation induced detwinning, Ni segregation and grain coarsening as discovered in binary Al-Ni alloys are mostly absent in the ternary Al-Ni-Ti alloys. Moreover, the ternary Al-Ni-Ti alloys have outstanding thermal stability. Density function theory calculations reveal the synergetic pinning effect of Ni-Ti solute pairs on incoherent twin boundaries. This study demonstrates that the proper selection of synergistic solute pairs is critical to improve the thermal stability and mechanical properties of nanotwinned Al alloys.

3D Co-culture of Cancer-Associated Fibroblast with Oral Cancer Organoids

Limits of the available model have, in the long term, challenged the studies of cancer-associated fibroblasts (CAFs) and their interplay with cancer stem cells, one of the key driving forces of patients with oral squamous cell carcinoma (OSCC). In the present study, the 3-dimensional organoid model was employed to investigate whether co-culture with paralleled CAFs promotes stem-like properties of OSCC. Experimentally, tumor organoids and paralleled CAFs were generated from patients with OSCC. Then, the CD44⁺ cells in organoids were sorted out by flow cytometry and co-cultured with CAFs in Matrigel. The results showed that co-culture with CAFs enhances the organoid-forming ability of CD44⁺ cells and that this effect was blocked when production or uptake of lactate in CAFs or CD44⁺ cells was inhibited. Furthermore, the expression levels of CD44 and OCT-4 were detected in organoids incubated with lactate, via immunofluorescence or Western blot assay. The results demonstrated that treatments with lactate promote the organoid-forming ability of CD44⁺ cells, as well as the expression of CD44 and OCT-4 at the protein level in OSCC organoids.

Intraspecific Diversity and Taxonomy of Emmonsia crescens

Emmonsia crescens is known as an environmental pathogen causing adiaspiromycosis in small rodents. As the generic name Emmonsia is no longer available for this species, its taxonomic position is re-evaluated. The intraspecific variation of Emmonsia crescens was analyzed using molecular, morphological, and physiological data, and the relationship between frequency of adiaspiromycosis and body temperature of host animals was explored. A North American and a pan-global lineage could be discerned, each with subclusters at low genetic distance. European strains produced the classical type of very large adiaspores, while in the North American lineage adiaspores relatively small, resembling the broad-based budding cells of Blastomyces. Members of the closely related genus Emergomyces may exhibit large, broad-based in addition to small, narrow-based budding cells. We conclude that the morphology of the pathogenic phase in these fungi differs gradationally between species and even populations, and is therefore less suitable as a diagnostic criterion for generic delimitation. Two Emmonsia species are reclassified in Emergomyces.

Targeted characterization of acylated compounds from Scrophulariae Radix using liquid chromatography coupled with Orbitrap mass spectrometry and diagnostic product ion-based data analysis

Acylated compounds are often present in herbal medicines. In this study, a diagnostic product ion-based strategy was established to comprehensively characterize acylated compounds in Scrophulariae Radix. After untargeted data acquisition using ultra-high performance liquid chromatography coupled with Orbitrap mass spectrometry, the data were processed by three-stage diagnostic product ions. First, diagnostic product ions corresponding to the acyl groups (cinnamoyl, p-coumaroyl, feruloyl, and caffeoyl) were used to search 90 compounds. Second, these compounds were divided into three categories using diagnostic product ions for phenylethanoid glycosides, iridoid glycosides, and phenylpropanoids, respectively. Last, the linkage position of the acyl group to iridoid glycosides was discriminated via the third-stage diagnostic product ions. As a result, 90 acylated compounds were characterized, and 37 of them were reported from Scrophulariae Radix for the first time.

Thick grain boundary induced strengthening in nanocrystalline Ni alloy

Grain refinement has been extensively used to strengthen metallic materials for decades. Grain boundaries act as effective barriers to the transmission of dislocations, consequently leading to strengthening. Conventional grain boundaries have a thickness of 1-2 atomic layers, typically ∼0.5 nm for most metallic materials. Here, we report, however, the formation of ∼3 nm thick grain boundaries in a nanocrystalline Ni alloy. In situ micropillar compression studies coupled with molecular dynamics simulations suggest that the thick grain boundaries are stronger barriers than conventional grain boundaries to the transmission of dislocations. This study provides a fresh perspective for the design of high strength, deformable nanostructured metallic materials.

Mandibular reconstruction using the deep circumflex iliac artery free flap: effect of the length of bone harvested on donor site morbidity

The aim of this study was to assess the amounts of pain and morbidity that are associated with the length of the harvested anterior iliac bone graft (cm), and their effect on the contour of the donor site and activities of daily life. A total of 62 patients who had mandibular reconstruction using an iliac bone graft were enrolled in this study at the Wuhan University Hospital. The same surgical standards were used throughout. We divided the patients into two groups depending to the length of the graft (<9cm or 9cm or more). The amount and duration of the pain, the time necessary to walk normally, abnormalities of sensation, contour of the donor site, length of the scar, and the patients' satisfaction with the donor site were evaluated, and outcomes in the two groups compared. The worst pain after operation (p=0.001) the length of the scar (p=0.001), and the time needed before the patients were able to walk (p=0.001) differed significantly between the two groups. There was no significant difference between the two groups regarding other complications. The anterior iliac crest might still be considered to be an ideal donor site for large mandibular defects.

Multiple perspectives of qingkailing injection-fraction-single compound in revealing the hepatotoxicity of baicalin and hyodeoxycholic acid

ETHNOPHARMACOLOGICAL RELEVANCE

The complexity of ingredients in traditional Chinese medical formulas and the limited consideration of toxicological responses are fundamental issues that hamper prognostic information of drug quality control.

MATERIALS AND METHODS

A multidisciplinary approach for quality control of Qingkailing injection (QKL) regarding drug induced liver toxicity was described for the first time. High content image analysis (HCA) was combined with reverse-phase chromatographic separation and high-resolution MS detection technologies to provide the dynamic responses of drug induced HepG2 cell injury. Firstly, a simple and rapid method for simultaneous qualification and quantification of 21 major constituents in QKL was established and validated using ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap mass spectrometer (UHPLC-Q-Orbitrap), which were operated in full MS/dd-MS² mode and thus simultaneously acquired quantitative high resolution (HR) full scan data and confirmatory HR MS² data. Secondly, repeated semi-preparation HPLC was applied to obtain four fractions (F1-F4) for HCS analysis. Finally, potential hepatotoxicity was determined by five hepatotoxicity biomarkers, including cell loss, DNA condense, glutathione (GSH) depletion, reactive oxygen species (ROS) formation, and mitochondria membrane potential (MMP) depolarization.

RESULTS

The detection in polarity switching mode empowered the coverage of comprehensive constituents with different chemical properties. Satisfactory linearity precisions, repeatability, stability, and recovery were achieved. QKL injection significantly induced HepG2 cell injury above the concentration of 1.25% (v/v). Meanwhile, flavone glycosides (F3) and stinasterols (F4) fractions exhibited hepatotoxicity above 75μg/mL and 50μg/mL, respectively. Still further, baicalin originated from F3 significantly caused cell loss and glutathione (GSH) depletion. In parallel, hyodeoxycholic acid from F4 induced cell loss, nucleus condense, and GSH reduction as well.

CONCLUSIONS

Our work provides multiple perspectives based on injection-fractions-single compound format to improve QKL pharmacovigilance through revealing the potential hepatotoxic material basis. Additionally, our study provides an integrating paradigm for the comprehensive and systematic quality control of traditional Chinese medical formulas.

An integrated strategy for rapid discovery and identification of the sequential piperine metabolites in rats using ultra high-performance liquid chromatography/high resolution mass spectrometery

Piperine, one of the major bioactive constituents isolated from natural flavorings and medicinal-culinary herbs, possesses various biological activities. In the present study, an integrated strategy based on ultra high-performance liquid chromatography/high resolution mass spectrometry was established to reveal piperine metabolism in rats. First of all, post-acquisition data-mining methods, including high resolution extracted ion chromatograms (HREICs) and multiple mass defect filtering (MMDF), were used to screen piperine metabolite candidates in a full-scan HRMS¹ level. Then, parent ion list-dynamic exclusion coupled with data-dependent data-acquisition method was utilized to acquire MSⁿ datasets. In addition, the established reverse molecular assembly (RMA) approach based on paired diagnostic product ions (pDPIs) coupled with neutral loss fragments (NLFs) was used to ascertain and identify the major-to-trace piperine metabolites efficiently. And then, the calculated ClogP values were utilized to distinguish the positional isomers. As a result, a total of 148 piperine metabolites were detected and characterized tentatively. The results demonstrated that piperine mainly underwent hydrogenation, dehydrogenation, hydroxylation, glucuronide conjugation, sulfate conjugation, ring-cleavage, and their composite reactions. Our results not only provided novel and useful data to better understand the safety, toxicity and efficacy of this potential therapeutic agent, but also indicated that the proposed strategy was reliable for a rapid discovery and identification drug-related constituents in vivo.

Adiponectin inhibits oxidization-induced differentiation of T helper cells through inhibiting costimulatory CD40 and CD80

Adiponectin is a multifunctional adipokine that has several oligomeric forms in the blood stream, which broadly regulates innate and acquired immunity. Therefore, in this study, we aimed to observe the differentiation of T helper (Th) cells and expression of costimulatory signaling molecules affected by adiponectin. The mRNA and protein expression levels of adiponectin and its receptors in oxidized low density lipoprotein cholesterol-treated endothelial cells were assayed by real time PCR and immunofluorescence. The endothelial cells were then treated with adiponectin with or without adipoR1 or adipoR2 siRNA and co-cultured with T lymphocytes. The distribution of Th1, Th2 and Th17 subsets were assayed by flow cytometry. The effects of adiponectin on costimulatory signaling molecules HLA-DR, CD80, CD86 and CD 40 was also assayed by flow cytometry. The results showed that endothelial cells expressed adiponectin and its receptor adipoR1 and adipoR2, but not T-cadherin. Adiponectin suppressed Th1 and Th17 differentiation through adipoR1 receptor, contributed to the inhibition of CD80 and CD40, and inhibited differentiation of Th1 and Th17 by inhibiting antigen presenting action.

Assessment of heavy metals in surface sediments from Gansu section of Yellow River, China

The concentrations of Cu, Fe, Mn, Ni, Zn, Cr, Pb, and Cd in 28 samples collected from bottom sediments in the Gansu section of Yellow River, China, were investigated in order to evaluate their distribution and pollution level. The measured metals in the sediments were found to be in the range of Cu 15.52∼57.50 mg/kg, Fe 19593.24∼69963.42 mg/kg, Mn 472.70∼1491.67 mg/kg, Ni 5.10∼74.28 mg/kg, Zn 64.61∼173.83 mg/kg, Cr 57.68∼183.47 mg/kg, Pb 1.21∼28.36 mg/kg, and Cd 0.35∼4.25 mg/kg. The mean values of the heavy metal contents were arranged in the following decreasing order: Fe > Mn > Cr > Zn > Ni > Cu > Pb > Cd. There were significantly positive correlations between Cu, Fe, Mn, and Zn. However, principal component analysis (PCA) extracted two factors with Eigenvalues explaining 62.15 % of the total variance. Cu, Fe, Mn, Zn, and Cr had a natural origin controlled by the first factor. Ni and Pb could originate anthropogenic sources controlled by the second factor. Cd could be affected by natural geological background and human activity. It was attributed principally to anthropogenic activities that the geo-accumulation index, enrichment factor, and pollution load index of Cr were all higher than other measured metals. Zn appears to pose no risk at all of the sites of the system. The pollution class of sediment from the Gansu section in the upstream of Yellow River was 0∼1, from unpolluted to moderately polluted degree.

DNA-PKcs activates the Chk2-Brca1 pathway during mitosis to ensure chromosomal stability

The catalytic subunit of DNA-dependent protein kinase (DNA-PKcs) is known to have a critical role in DNA double-strand break repair. We have previously reported that DNA-PKcs is activated when cells enter mitosis and functions in mitotic spindle assembly and chromosome segregation. Here we report that DNA-PKcs is the upstream regulator of the Chk2-Brca1 pathway, which impacts microtubule dynamics, kinetochore attachment and chromosomal segregation in mitosis. Downstream from Chk2, Brca1 promotes monoubiquitination of γ-tubulin to inhibit microtubule nucleation and growth. We found that DNA-PKcs is essential for mitotic Chk2 phosphorylation at Thr68. As in Chk2- and Brca1-deficient cells, loss of DNA-PKcs resulted in chromosome misalignment and lagging during anaphase owing to elevation in microtubule dynamics. Importantly, these mitotic aberrations in DNA-PKcs-defective cells were alleviated by the overexpression of phosphomimetic Chk2 or Brca1 mutant proteins but not their wild-type counterparts. Taken together, these results demonstrate that DNA-PKcs regulates mitotic spindle organization and chromosomal instability via the Chk2-Brca1 signaling pathway.

Proposal for new best estimates of the soil-to-plant transfer factor of U, Th, Ra, Pb and Po

There is increasing interest in radiological assessment of discharges of naturally occurring radionuclides into the terrestrial environment. Such assessments require parameter values for the pathways considered in predictive models. An important pathway for human exposure is via ingestion of food crops and animal products. One of the key parameters in environmental assessment is therefore the soil-to-plant transfer factor to food and fodder crops. The objective of this study was to compile data, based on an extensive literature survey, concerning soil-to-plant transfer factors for uranium, thorium, radium, lead, and polonium. Transfer factor estimates were presented for major crop groups (Cereals, Leafy vegetables, Non-leafy vegetables, Root crops, Tubers, Fruits, Herbs, Pastures/grasses, Fodder), and also for some compartments within crop groups. Transfer factors were also calculated per soil group, as defined by their texture and organic matter content (Sand, Loam, Clay and Organic), and evaluation of transfer factors' dependency on specific soil characteristics was performed following regression analysis. The derived estimates were compared with estimates currently in use.

Experimental study on in vitro tumor cell killing by focused bi-frequency ultrasound activated hematoporphyrin derivatives

OBJECTIVE

As ultrasound has become an important therapeutic technique on tumor, in order to find the cell-killing effect of focused bi-frequency ultrasound activated hematoporphyrin derivatives, experimental study was processed in vitro.

METHODS

Tumor cells K562 and SW-480 were killed by focused bi-frequency ultrasound activated hematoporphyrin (Hp) derivatives under optimized ultrasonic parameters and the cell-killing effect was tested by MTT (Thiazolyl blue: 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) technique.

RESULTS

The lower frequency (0.6 MHz) was better than the higher (1.1 MHz) in activating hematoporphyrin derivatives; the bi-frequency was better than mono-frequency, and the cell-killing efficiency was 2-3 times of sum of the two kinds of ultrasounds which constitute bi-frequency. Incubation for the 16 h was better than 4 h after the cells exposed to the ultrasound.

CONCLUSION

The method of killing tumor cells by focused bi-frequency ultrasound activated hematoporphyrin derivatives is presented and evaluated in this paper.

[Differentiation of Ziyi Bencao as an apocrypha]

It is generally believed that Ziyi Bencao is a book of the pre-Qin period. By studies on several aspects, including ancient bibliographical records, relics unearthed in Mawangdui Han tombs, nomenclature of ancient book titles, the date of appearance of ancient classics, contradictions between the time of activities of Bian Que and Ziyi, it is concluded that, in the pre-Qin period, there were no classic of herbology of any kind, even less Ziyi Bencao. The books entitled Ziyi Bencao recorded in bibliographies after Han Dynasty are all apocryphas made by Han authors.

[Differential analyses on the historical relationship between Zhenglei bencao (herbology of classified syndromes) and Mingyi Bie Lu (appendant records of famous physicians)]

This author claims that, by using the approach of "inclusion of all canons", Tao Hongjing incorporated the 365 kinds of drugs from the earliest canon "Shen Nong's Herbological Canon" with another 365 kinds of "subordinated drugs from famous physicians", including Wu Pu and Li Dangzhi etc. to compile his 7-volume "Collected variorum of herbological canon". Owing to the changes and modifications made on the term "subordinated drugs from famous physicians" by the prefaces of herbological works of successive ages, the misunderstandings that the other 365 appendant kinds of drug were derived from an available Ming Yi Bie Lu and that the preface by Tao Yinju of the Liang Dynasty in Zhenglei Bencao was the preface of the book Mingyi Bielu were thuw formed.

[Ultrasonic measurement of the elastic properties of goat condyles]

OBJECTIVE

The purpose of this experiment is to investigate the elastic properties of goat mandibular condyles and to provide basic constants for biomechanical study of temporomandibular joint.

METHODS

A fresh goat mandible was adopted and the standard condyle specimen of 4 mm x 6 mm x 10 mm was obtained from it. The structure density of the condyle was determined according to Archimede's principle. The transmitting velocities of ultrasonic wave in different directions of goat condyles were measured by using the ultrasonic system, which was composed of a transmitting transducer of 1.25 MHz, a receiving transducer of 2.5 MHz, an ultrasonic analyzer (5052UA) and a digital storage oscilloscope (HP54601A). The elastic coefficients and technical constants could be calculated by elastic equations.

RESULTS

The structural density of the sample and the wave velocities in different directions of the condyle were both obtained by direct measurement. And then, nine elastic coefficients and all of the technical constants of orthotropic condyles were calculated.

CONCLUSION

1. It is practicable to measure elastic properties of the condyle by using ultrasonic technique. 2. Goat condyles of the mandible are a type of anisotropic and linearly elastic material. 3. The direction perpendicular to the transverse ridge of the goat condyle has the highest Young's modulus. As to shear modulus, the direction along the transverse ridge shows the highest value.

On the direction and magnitude of radical substituent effects: the role of polar interaction on thermodynamic stabilities of benzylic C-H bonds and related carbon radicals

The C-H bond dissociation enthalpies (BDEs) of polarized benzylic molecules, i.e., para-substituted phenylacetonitriles (PANs), and the spin variations of the radicals of the general type p-GC6H4CH*-Y were investigated using density functional theory (DFT) calculations. In contrast to the commonly observed S-type substituent effect (see text), the present work shows that there should be three (rather than one) primary patterns (i.e., S, O, and counter-O) for remote G to affect spin and radical stability, depending upon the polarity of the alpha-Y group. Correlation analyses reveal that both the direction and magnitude of spin/radical effects are quantitatively related to the intensity of polar interaction in radical system, as registered by either the calculated group charges of the phenyl ring (C(Ph)) or by the polar constant sigma(+)s (Figures 1-4). A unified platform (Scheme 1) to rationalize the apparent differences of radical substituent effect is proposed.

A story: unpaired adenosine bases in ribosomal RNAs

In 1985 an analysis of the Escherichia coli 16 S rRNA covariation-based structure model revealed a strong bias for unpaired adenosines. The same analysis revealed that the majority of the G, C, and U bases were paired. These biases are (now) consistent with the high percentage of unpaired adenosine nucleotides in several structure motifs. An analysis of a larger set of bacterial comparative 16 S and 23 S rRNA structure models has substantiated this initial finding and revealed new biases in the distribution of adenosine nucleotides in loop regions. The majority of the adenosine nucleotides are unpaired, while the majority of the G, C, and U bases are paired in the covariation-based structure model. The unpaired adenosine nucleotides predominate in the middle and at the 3' end of loops, and are the second most frequent nucleotide type at the 5' end of loops (G is the most common nucleotide). There are additional biases for unpaired adenosine nucleotides at the 3' end of loops and adjacent to a G at the 5' end of the helix. The most prevalent consecutive nucleotides are GG, GA, AG, and AA. A total of 70 % of the GG sequences are within helices, while more than 70 % of the AA sequences are unpaired. Nearly 50 % of the GA sequences are unpaired, and approximately one-third of the AG sequences are within helices while another third are at the 3' loop.5' helix junction. Unpaired positions with an adenosine nucleotide in more than 50 % of the sequences at the 3' end of 16 S and 23 S rRNA loops were identified and arranged into the A-motif categories XAZ, AAZ, XAG, AAG, and AAG:U, where G or Z is paired, G:U is a base-pair, and X is not an A and Z is not a G in more than 50 % of the sequences. These sequence motifs were associated with several structural motifs, such as adenosine platforms, E and E-like loops, A:A and A:G pairings at the end of helices, G:A tandem base-pairs, GNRA tetraloop hairpins, and U-turns.

[Discussion on sources of texts of Meng Sheng's Herbology of dietotherapy cited in Jinling edition of Compendium of materia medica]

Most of the citations of Meng Sheng's Herbology of Dietotherapy in Compendium of Materia Medica are originated from the Daguan Herbology and Zhenghe Herbology. When comparing these sources of citations in Compendium of Materia Medica with the texts in Daguan and Zhenghe, it can be found that there are differences, In Compendium of Materia Medica, it is indicated that these sources marked "Meng Sheng's Herbology of Dietotherapy" are actually derived from other sources, while citations from other sources are marked "Meng Sheng's Herbology of Dietotherapy" which are not found in Classified Herbology (Zhenglei ben cao). This might be due to the editions of Daguan and Zhenghe Li Shizhen applied are different.

[Discassion on the date of appearance of the title Shen nong ben caojing (Shennong's Herbal Classic)]

It is said, in general literatures, that the title of shen nong ben cao jing appeared in pre- Qin period. It can be negated, through studies on Han shu yi wen zhi (Biblie - graphies in Book of Han Dynasty), relics unearthed from Han tombs in Mawangdui, the history of nomencleture for ancient books, and the date of appearance of ancient canons, that the said - title first appeared in the pre - Qin period. The name of "ben cao" was first appeared in western Han dynasty. There were officials of necromaneer (fan shi) and ben cao in western Han dynasty. During Chengdi Emperor of Han, some seventy such officials were dismissed and returned to their homelands. Pingdi Emperor re-summoned these officials. Several scores of officials responded to the edict, among them, those responsible for ben cao complied a book on ben cao (herbology) and alleged it to be written by shennong so as to win confidence with the authority and to acquire the official title of ben cao dai zhao (Herbal Attendant) for themselves. It is, therefore, natural that the title of shen nong ben cao jing can only have appeared at the time of Herbal Attendant in Western Han dynasty.

Study on the difference between Shennong's drug nature quoted by Wu Puu and by Shennong's drug in material medical in classified syndromes (Zheng)

Several questions were mentioned through the analysis and comparison of "Shennong's drug nature" (DN) as quoted by Wu Pu's Meteria Madica (WP) and Materia Medica of Classified Syndrome (Zheng) (ZL). These include: (1) The DN in ZL are incomplete, the "toxic nontoxic" terms were absent here; (2) There were different editions of ancient "Shennong's Canon of Materia Medica", carrying different numbers of drugs, including 365 kinds, 595, 441, 319 kinds respectively; (3) some of the drugs indicated as DN were, strangely, indicated as "drugs of supplemented Records" in ZL.

Removal of endotoxin from aqueous solutions by affinity membrane

Endotoxin was removed by affinity membranes with histidine immobilized as affinity ligand. Macropore cellulose membrane was prepared from filter paper by alkaline treatment and chemical crosslinking, and was used as matrix for the immobilization of affinity ligand. The matrix membrane was derived by hexamethylenediamine and activated by glutaraldehyde before histidine was immobilized. Membrane cartridges containing 40 or 80 sheets of affinity membrane were also prepared, which can be used to remove pyrogen from aqueous solutions. Using a cartridge with 40 sheets of affinity membrane, the endotoxin content in solution can be reduced to a minimum of 0.12 EU/mL.

Application of multiple-quantum line narrowing with simultaneous 1H and 13C constant-time scalar-coupling evolution in PFG-HACANH and PFG-HACA(CO)NH triple-resonance experiments

Many triple-resonance experiments make use of one-bond heteronuclear scalar couplings toestablish connectivities among backbone and/or side-chain nuclei. In medium-sized(15-30 kDa) proteins, short transverse relaxation times of Calpha single-quantum stateslimit signal-to-noise (S/N) ratios. These relaxation properties can be improved usingheteronuclear multiple-quantum coherences (HMQCs) instead of heteronuclear single-quantumcoherences (HSQCs) in the pulse sequence design. In slowly tumbling macromolecules, theseHMQCs can exhibit significantly better transverse relaxation properties than HSQCs.However, HMQC-type experiments also exhibit resonance splittings due to multiple two- andthree-bond homo- and heteronuclear scalar couplings. We describe here a family of pulsed-field gradient (PFG) HMQC-type triple-resonance experiments using simultaneous 1H and13C constant-time (CT) periods to eliminate the t1 dependence of these scalar couplingeffects. These simultaneous CT PFG-(HA)CANH and PFG-(HA)CA(CO)NH HMQC-typeexperiments exhibit sharper resonance line widths and often have better S/N ratios than thecorresponding HSQC-type experiments. Results on proteins ranging in size from 6 to 30 kDashow average methine CalphaH HMQC:HSQC enhancement factors of 1.10 +/- 0.15, withabout 40% of the cross peaks exhibiting better S/N ratios in the simultaneous CT-HMQCversions compared with the HSQC versions.

Phase labeling of C-H and C-C spin-system topologies: application in constant-time PFG-CBCA(CO)NH experiments for discriminating amino acid spin-system types

Triple-resonance experiments facilitate the determination of sequence-specific resonance assignments of medium-sized 13C,15N-enriched proteins. Some triple-resonance experiments can also be used to obtain information about amino acid spin-system topologies by proper delay tuning. The constant-time PFG-CBCA(CO)NH experiment allows discrimination between five different groups of amino acids by tuning (phase labeling) independently the delays for proton-carbon refocusing and carbon-carbon constant-time frequency labeling. The proton-carbon refocusing delay allows discrimination of spin-system topologies based on the number of protons attached to C alpha and C beta atoms (i.e. C-H phase labeling). In addition, tuning of the carbon-carbon constant-time frequency-labeling delay discriminates topologies based on the number of carbons directly coupled to C alpha and C beta atoms (i.e. C-C phase labeling). Classifying the spin systems into these five groups facilitates identification of amino acid types, making both manual and automated analysis of assignments easier. The use of this pair of optimally tuned PFG-CBCA(CO)NH experiments for distinguishing five spin-system topologies is demonstrated for the 124-residue bovine pancreatic ribonuclease A protein.