1,5,6-Trimethoxy-2,7-dihydroxyphenanthrene from Dendrobium officinale Exhibited Antitumor Activities for HeLa Cells.

Natural products are irreplaceable reservoirs for cancer treatments. In this study, 12 phenanthrene compounds were extracted and isolated from Dendrobium officinale. Each chemical structure was identified using comprehensive NMR analysis. All compounds were evaluated for their cytotoxic activities against five tumor cell lines, i.e., HeLa, MCF-7, SK-N-AS, Capan-2 and Hep G2. Compound 5, 1,5,6-trimethoxy-2,7-dihydroxyphenanthrene, displayed the most significant cytotoxic effect against HeLa and Hep G2 cells, with an IC50 of 0.42 and 0.20 µM. For Hela cells, further experiments demonstrated that compound 5 could obviously inhibit cell migration, block cell cycle in the G0/G1 phase and induce apoptosis. Expression measurements for p53 indicated that knock down of p53 by siRNA could mitigate the apoptosis induced by compound 5. Therefore, the compound 5 is a potential candidate drug for HeLa cells in cervical cancer.

Biosynthesis of Vanillin by Rational Design of Enoyl-CoA Hydratase/Lyase.

Vanillin holds significant importance as a flavoring agent in various industries, including food, pharmaceuticals, and cosmetics. The CoA-dependent pathway for the biosynthesis of vanillin from ferulic acid involved feruloyl-CoA synthase (Fcs) and enoyl-CoA hydratase/lyase (Ech). In this research, the Fcs and Ech were derived from Streptomyces sp. strain V-1. The sequence conservation and structural features of Ech were analyzed by computational techniques including sequence alignment and molecular dynamics simulation. After detailed study for the major binding modes and key amino acid residues between Ech and substrates, a series of mutations (F74W, A130G, A130G/T132S, R147Q, Q255R, ΔT90, ΔTGPEIL, ΔN1-11, ΔC260-287) were obtained by rational design. Finally, the yield of vanillin produced by these mutants was verified by whole-cell catalysis. The results indicated that three mutants, F74W, Q147R, and ΔN1-11, showed higher yields than wild-type Ech. Molecular dynamics simulations and residue energy decomposition identified the basic residues K37, R38, K561, and R564 as the key residues affecting the free energy of binding between Ech and feruloyl-coenzyme A (FCA). The large changes in electrostatic interacting and polar solvating energies caused by the mutations may lead to decreased enzyme activity. This study provides important theoretical guidance as well as experimental data for the biosynthetic pathway of vanillin.

An interaction study of online learning satisfaction with parent-child relationships and trait coping styles.

As the physical and mental development of the young is not only influenced by the parent-child relationship (PR) and the student's academic performance, but also moderated by trait coping styles (TCS), the changes between these three during the online learning period in an epidemic need to be reconsidered. This study aims to explore the factors affecting online learning satisfaction (OLS) among students and their interaction with parent-child relationship and trait coping style. A web-based questionnaire was employed, encompassing general information, the Trait Coping Style Questionnaire (TCSQ), and queries related to OLS. A total of 1,287 valid questionnaires were collected, with 593 from junior high school students, 197 from high school students, and 497 from university students. Our findings indicate that parent-child relationship (PR), positive coping style (PCS), and learning status (LS) showed a positive correlation with OLS (r=0.110, P<0.001; r=0.786, P<0.001). Conversely, negative coping style (NCS) presented a negative correlation with OLS (r=-0.186, P<0.01). Multiple regression analysis of OLS reveals that PR has a significant impact on OLS (P<0.001, ß=0.291), as does LS (P<0.001, ß=0.767). However, trait coping styles (TCS) appear to have no significant effect on OLS. Notably, PR plays a significant and positive mediating role between LS and OLS, with a mediation effect of 0.0132 (P<0.05), accounting for 1.682% of the total effect. These findings suggest that strengthening parent-child interactions and fostering adaptive coping mechanisms could play a crucial role in enhancing students' satisfaction with online education. Such improvements could potentially contribute to superior academic outcomes and overall student well-being.

Coassembly Nanomedicine Mediated by Intermolecular Interactions Between Methotrexate and Baricitinib for Improved Rheumatoid Arthritis Treatment.

The combination of anti-rheumatoid arthritis (RA) drugs methotrexate (MTX) and baricitinib (BTN) has been reported to improve RA treatment efficacy. However, study on the strategy of combination is elusive when considering the benefit of the synergy between MTX and BTN. In this study, we found that the N-heterocyclic rings in the MTX and BTN offer hydrogen bonds and π-π stacking interactions, driving the formation of exquisite vesicular morphology of nanovesicles, denoted as MB NVs. The MB NVs with the MTX/BTN weight ratio of 2:1, MB NVs (2:1), showed an improved anti-RA effect through the synergy between the anti-inflammatory and antiproliferative responses. This work presents that the intermolecular interactions between drug molecules could mediate the coassembly behavior into nanomedicine as well as the therapy synergy both in vitro and in vivo, which may provide further understanding on the rational design of combination nanomedicine for therapeutic purposes.

Exploring the Pivotal Components Influencing the Side Effects Induced by an Analgesic-Antitumor Peptide from Scorpion Venom on Human Voltage-Gated Sodium Channels 1.4 and 1.5 through Computational Simulation.

Voltage-gated sodium channels (VGSCs, or Nav) are important determinants of action potential generation and propagation. Efforts are underway to develop medicines targeting different channel subtypes for the treatment of related channelopathies. However, a high degree of conservation across its nine subtypes could lead to the off-target adverse effects on skeletal and cardiac muscles due to acting on primary skeletal muscle sodium channel Nav1.4 and cardiac muscle sodium channel Nav1.5, respectively. For a long evolutionary process, some peptide toxins from venoms have been found to be highly potent yet selective on ion channel subtypes and, therefore, hold the promising potential to be developed into therapeutic agents. In this research, all-atom molecular dynamic methods were used to elucidate the selective mechanisms of an analgesic-antitumor ß-scorpion toxin (AGAP) with human Nav1.4 and Nav1.5 in order to unravel the primary reason for the production of its adverse reactions on the skeletal and cardiac muscles. Our results suggest that the rational distribution of residues with ring structures near position 38 and positive residues in the C-terminal on AGAP are critical factors to ensure its analgesic efficacy. Moreover, the substitution for residues with benzene is beneficial to reduce its side effects.

Studies on the stability of salvianolic acid B as potential drug material.

INTRODUCTION: Salvianolic acid B (Sal B) is one of the major water-soluble compounds isolated from the roots of Salvia miltiorrhiza, which is widely used as a traditional Chinese medicine. Although much research on the general stability of Sal B has been undertaken and reported, there is still a need for further study of the stability required as a potential drug material. OBJECTIVE: To study the stability of Sal B in the solid state and in normal saline (NS) solution during storage, as required in the ICH guidelines (2003) and Chinese Pharmacopoeia (2005). METHODOLOGY: Sal B stability was analysed using the high-performance liquid chromatography (HPLC) method described in the Chinese Pharmacopoeia. HPLC coupled with time-of-flight mass spectrometry (HPLC-TOFMS) was applied for the separation and identification of the degradation products of Sal B. RESULTS: In the solid state, Sal B packaged in aluminium foil bags was stable for 6 months under 'accelerated conditions' (40°C, 75% relative humidity, RH). However, solid Sal B degradation was observed under open exposure to stress conditions of high temperature (60°C) or high humidity (92.5 or 75% RH). In NS solution, Sal B underwent severe degradation under accelerated conditions. Through HPLC-TOFMS, nine degradation products were identified and the possible degradation pathway was deduced. CONCLUSION: The results demonstrate that the potential drug material Sal B could be used in a solid formulation, but is not suitable for use as a liquid formulation.

Stereoselective hydrogenation on the exocyclic and conjugated double bond of sesquiterpene lactones by Aspergillus versicolor D-1.

Aspergillus versicolor D-1 was employed to convert dehydrocostuslactone (1) and 3-hydroxy-1(10),3,11(13)-guaiatriene-12,6-olide-2-one (5) stereoselectively. The reactions occurring were specific hydrogenation on the exocyclic alpha,beta-double bond of sesquiterpene lactones with excellent conversion. Products were identified by the analysis of their spectra such as UV, IR, MS, (1)H, (13)C NMR, and NOESY, and the structure of one new compound was elucidated. The characteristic of the stereoselective hydrogenation was also discussed and suggested.

A sensitive and rapid immunoassay for Mycoplasma pneumoniae in children with pneumonia based on single-walled carbon nanotubes.

Mycoplasma pneumoniae(MP) is a leading pathogen of respiratory infection, especially community-acquired pneumonia (CAP), in children worldwide. However, its diagnosis is frequently ineffective because bacterial culture and serology test are usually positive 1-2 weeks or more after the disease onset. To achieve a better detection efficiency, the single-walled carbon nanotubes(SWCNT) were coupled with the colloidal gold-monoclonal antibody immunochromatographic strips(CGIC). Interestingly, the SWCNT/CGIC assay allowed MP identification, with a detection limit of 1 × 102 copies/ml. Using referenced throat swabs of 97 MP and 40 non-MP cases, the assay yielded 72.2% sensitivity, 100.0% specificity, 100.0% positive predictive value (PPV), 59.7% negative predictive value (NPV). In summary, our assay was far more effective than any conventional methods for the diagnosis of acute MP. The ease of use, rapid and stability further enhance its feasibility for clinical use on-site.

Screening for potential serum-based proteomic biomarkers for human type 2 diabetes mellitus using MALDI-TOF MS.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a complex, pandemic disease contributing towards the global burden of health issues. To date, there are no simple clinical tests for the early detection of T2DM. METHOD: To identify potential peptide biomarkers for such applications, 406 sera of T2DM patients (n = 206) and healthy controls (n = 200) are analyzed by using MALDI-TOF MS with a cross-sectional case-control design. RESULT: Six peptides (peaks m/z 1452.9, 1692.8, 1946.0, 2115.1, 2211.0 and 4053.6) are identified as candidate biomarkers for T2DM. A diagnostic model constructed with six peptides is able to discriminate T2DM patients from healthy controls, with an accuracy of 82.20%, sensitivity of 82.50%, and specificity of 77.80% in the validation set. Peptide peaks m/z 1452.9 and 1692.8 are identified as fragments of the complement C3f, while peptide peaks m/z 1946.0, 2115.1, and 2211.0 are identified as the fragments of kininogen 1 isoform 1 precursor. CONCLUSION: This study reinforces proteomic analyses as a potential technique for defining significant clinical peptide biomarkers, providing a simple and convenient diagnostic model for T2DM in clinical examination.

[Preliminary analysis on China Agricultural University chicken resource population based on genomic scanning].

Combining the technique of multiplex-PCR and the fluorescent semi-automated detection, a large-scale genome scanning was performed for 440 chickens, which was derived from China Agricultural University chicken resource families, within three generations. Fifty-five microsatellite markers were analyzed for this study. Those 55 microsatellite loci accorded with the characters of Mendelian co-inheritance. The heterozygosities ranged from zero to 0.89, with 72% of loci having a heterozygosity of more than 0.60. The polymorphism information content (PIC) ranged from 0 to 0.85, in which 70% of those loci had a PIC of more than 0.50 but their distribution varied in line A and line C. The allele frequency was significantly different between line A and line C at most loci (P < 0.01). At the same time, gene accordance inclination was found in line C. The Nei population resemble coefficient and standard genetic distance were 0.1002 and 0.8928.

[Research progress and prospect of animal gene targeting].

Established upon the embryo stem cell technique and homologous recombination, gene targeting has been widely used in the genome specific manipulation, especially applied in the genetic trait modification of transgenic animal. Our paper reviewed the history of transgenic animal, somatic cloning and gene targeting, which indicates the influence towards the current status and prospect of the transgenic animal production.

[The factors affecting the efficiency of mutiplex PCR].

In the research,the outputs of different cycle parameters, PCR buffer and reaction volumes are compared. The results indicated that the annealing temperature, annealing time, elongated time and ingredient of PCR buffer affected mutiplex PCR, but the reaction volume and cycle number had few effect on it.

The isolation and identification of a light-induced protein in alfalfa sprouts and the cloning of its specific promoter.

We used 2D-PAGE to isolate a light-induced protein (AL-A) that is expressed abundantly in light-growth alfalfa sprouts. The seven amino acids of the N-terminal region of the protein were identified, and we searched for the protein in GenBank using the BLAST program. The results of the homology analysis showed that the amino acid sequence of the isolated protein is most similar to one from a pea plastocyanin. To identify the protein, we amplified and sequenced the DNA fragment encoding AL-A from genomic alfalfa DNA. We found that the AL-A gene was highly homologous (90%) to the sequences from the pea plastocyanin via multiple alignments, and the deduced protein precursor was predicted to be chloroplast-specific via the ChloroP computer program. The protein was named alfalfa-plastocyanin (AL-P). It was characterized as being a light-inducible protein, and RT-PCR analysis showed that AL-P mRNA transcription only occurred in the leaves of the alfalfa plant and the alfalfa seedlings growth in lighted conditions. PCR was also used to amplify the DNA fragment encoding the AL-P promoter (AL-Pp) from genomic alfalfa DNA. PlantCARE analysis of the promoter sequence indicated that both a typical TATA box and a CAAT box were located in the promoter sequence, and some of the cis-elements that are responsible for light responsiveness were also identified within this promoter region. The AL-P gene promoter fused to the ß-glucuronidase (GUS) reporter gene has been examined for expression in transgenic alfalfa seedlings. Our findings have a potential application in plant genetic engineering; the AL-Pp may be used to drive the expression of heterologous genes in transgenic alfalfa plants.

Identification and characterization of three impurities in clocortolone pivalate.

Clocortolone pivalate is a synthetic corticosteroid that can be used to cure corticosteroid-responsive dermatoses. Three previously unknown impurities detected by HPLC were isolated by semi-preparative LC. Based on the NMR and MS spectral data, these were identified as (6R,9R,16R)-9-chloro-6ß-fluoro-11ß,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione-21-pivalate (Impurity I), (9R,16R)-9-chloro-4-fluoro-11ß,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione-21-pivalate (Impurity II) and (9R,16R)-9-chloro-6α-fluoro-11ß,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione-11,21-dipivalate (Impurity III). The possible mechanism of the formation of the impurities is discussed.

Therapeutic effects of combination of paeoniflorin and albiflorin from Paeonia radix on radiation and chemotherapy-induced myelosuppression in mice and rabbits.

The aim of this study was to investigate the therapeutic effects of the combination of paeoniflorin and albiflorin (CPA) extracted from Paeonia radix on radiation and chemotherapy induced myelosuppression in two animal models: mice and rabbits. Mice were exposed to X-ray radiation (400 Roentgen), and both mice and rabbits were intraperitoneally injected with cyclophosphamide (100.0 mg/kg) and cytarabine chloride (92.7 mg/kg), respectively, for 3 days to induce myelosuppression. CPA was subsequently administrated intravenously at low (15.0 mg/kg for mice, 6.00 mg/kg for rabbits), intermediate (30.0 mg/kg for mice, 12.0 mg/kg for rabbits) and high (60.0 mg/kg for mice, 24.0 mg/kg for rabbits) doses, as well as orally (60.0 mg/kg for mice, 24.0 mg/kg for rabbits) for 7 days. Shenqi tablets were used as positive controls (oral administration of 936.0 mg/kg for mice, 336.0 mg/kg for rabbits). The administration of CPA significantly ameliorated myelosuppression in all cases. For the X-ray irradiated mice and the chemotherapy treated mice and rabbits, high dosages of CPA resulted in the recovery of, respectively, 94.4%, 95.3% and 97.7% of hemoglobin content; 67.7%, 92.0% and 94.3% of platelet numbers; 26.8%, 137.1% and 107.3% of white blood cell counts; as well as a reversal in the reduction of peripheral differential white blood cell counts. There was also a recovery of 50.9%, 146.1% and 92.3%, respectively, in the animals' relative spleen weight. Additionally, a recovery of 35.7% and 87.2% in the number of bone marrow nucleated cells was observed in the radio- and chemotherapy treated mice, respectively. Bone marrow white blood cell counts also resumed to normal levels. These results substantiate the marked therapeutic effects of CPA to ameliorate myelosuppression induced by radio and chemotherapy.

DNA methylation changes in cell line from beta-lactoglobulin gene targeted fetus.

The gene targeting combined somatic cell nuclear transfer is very useful in agriculture and medicine. Epigenetic modification of DNA by methylation is significant in regulating gene expression during mammalian development. During gene targeting, epigenetic status of donor cell nuclei may be changed in a series of processes, including homologous recombination, cell selection and cloning. We examined DNA methylation of six genes (beta-actin, VEGF, oct4, TERT, H19 and Igf2) and a repetitive sequence art2 in blg(+/-) cell line from beta-lactoglobulin (BLG) gene targeted fetus and the cells used for BLG gene targeting serve as control. The results demonstrated that the widespread changes of DNA methylation were found in blg(+/-) cell line. But the degree of variation was different. DNA methylation of VEGF in blg(+/-) was noticeably decreased. These observations suggest that DNA methylation variations may impact gene expression and finally induce abnormalities and lethality in later developmental stages.

Construction and characterization of a novel 13.34-fold chicken bacterial artificial chromosome library.

A chicken bacterial artificial chromosome (BAC) library consisting of 138,240 clones was constructed in vector pBeloBAC11 with genomic DNA isolated from female white-silk chicken. An average insert size of 118 kb was estimated from 452 randomly isolated clones, which indicate the library to be approximate 13.34-fold genome coverage. For the demonstration of the probability to pick out any unique genes or DNA markers from the library, 8 single-copy genes were screened out and the positive clones were yielded between 2 and 15 with an average of 11.125, in agreement with the estimated high genomic coverage of this library. Positive superpools were obtained for 40 microsatellite markers selected from different regions of chicken genome. The number of positive superpools for each marker varies from 1 to 15 with an average of 9.475.