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Minqin County is located in the Shiyang River Basin. As a typical arid area, it is eroded by the Badain Jaran and Tengger Desert all year round, and knowledge of the fungal diversity in this area is limited. Therefore, fungal community structure and distribution in the soil of the artificial forest, desert transition zone, farmland, and desert were investigated using amplicon sequencing of the fungal ITS gene. Ten fungal phyla and 23 classes were identified, including 1131 fungi OTUs, Sordariomycetes, Dothideomycetes, Pezizomycetes, and Agaricomycetes were the most abundant classes. Although most OTUs are shared among habitats, fungal community composition among samples was highly variable, which may influence the design of restoration practices in this area.

Five specimens, initially presumed to be Fuligo septica or Mucilago crustacea, were collected from Jilin Province and the Inner Mongolia Autonomous Region in China, but all five turned out to represent a new aethaloid species, Didymium yulii. This new species is characterized by pseudocapillitia without capillitia and an aethalioid fruiting body, features that are morphologically distinct from those of any other species of Didymium. To assess the phylogenetic relationships between D. yulii and other members of Didymium and in the Didymiaceae, sequences from two nonoverlapping targeted portions of nuc 18S rDNA (~450 bp and ~1050 bp) and translation elongation factor 1-alpha (tef1) were obtained and analyzed. The results indicate that D. yulii forms a single clade separate from other species of Didymium and the clade that contains M. crustacea, which strongly supports the identification of the five specimens as a new species.

The abuse of chemical fungicides not only leads to toxic residues and resistance in plant pathogenic fungi, but also causes environmental pollution and side effects on in humans and animals. Based on the antifungal activities of berberine, seven different types of berberine derivatives (A1-G1) were synthesized, and their antifungal activities against six plant pathogenic fungi were evaluated (Rhizoctonia solani, Botrytis cinerea, Fusarium graminearum, Phytophthora capsici, Sclerotinia sclerotiorum, and Magnaporthe oryzae).The results for antifungal activities in vitro showed that berberine derivative E1 displayed good antifungal activity against R. solani with a median effective concentration (ECBerberine derivative E20 merits further development as a new drug candidate with selective and excellent antifungal activity against R. solani. © 2022 Society of Chemical Industry.

OBJECTIVE. The purpose of this study was to develop an effective nomogram and artificial neural network (ANN) model for predicting recurrent hemoptysis after bronchial artery embolization (BAE). MATERIALS AND METHODS. The institutional ethics review boards of the two participating hospitals approved this study. Patients with hemoptysis who were treated with BAE were allocated to either the training cohort (Hospital A) or the validation cohort (Hospital B). The predictors of recurrent hemoptysis were identified by univariable and multivariable analyses in the training cohort. A nomogram and ANN model were then developed, and the accuracy was validated by the Harrell C statistic and ROC curves in both the training and validation cohorts. RESULTS. A total of 242 patients (training cohort, 141; validation cohort, 101) were enrolled in this study. The univariable and multivariable analyses revealed that age of 60 years old or older (hazard ratio [HR], 3.921; 95% CI, 1.267-12.127; p = 0.018), lung cancer (HR, 18.057; 95% CI, 4.124-79.068; p 0.16) according to the nomogram.

Background: Erythrina variegata has been widely used as a traditional medicine. Objective: The study was designed to evaluate the anxiolytic and anti-depressant effects of an extract from Erythrina variegata. Methods: The extract was evaluated for anxiolytic and anti-depressant action using the elevated plus maze, light/dark box, open field, forced swimming and tail suspension tests in mice. The mechanism of action was further elucidated using high-performance liquid chromatography with fluorescence detection methods to assay the levels of five neurotransmitters in brain. Results: The extract exhibited significant increase in the percentage of the open arms entries and the time spent in the open arms in the elevated plus maze test. The results of the light/dark box test revealed a significant increase in the amount of time spent in the light chamber. Extract- treated mice also produced significant increase in the number of crossings and rearings in the open field test.In the forced swimming and tail suspension tests, the extract was able to promote significant decrease in the immobility time. In addition, the extract significantly altered the levels of five neurotransmitters in the brain tissue. Conclusion: These findings suggest that Erythrina variegata presents potential anxiolytic and anti-depressant activity, and the mechanism may be related to the alteration of neurotransmitter levels. Keywords: Anxiolytic; anti-depressant; Erythrina variegata; elevated plus maze; forced swimming; neurotransmitters.

Tube indwelling is a key procedure in modern medicine. Careful tube setup is necessary to prevent unplanned extubation. The training for tube fixation is time- and resource-consuming, and optimal modes of training are currently being sought. Previous studies have compared workshops and flipped classroom models separately using conventional teaching strategies, but no study has examined a combination of both teaching models in nursing training.To compare the effectiveness of workshopsThis was a prospective cohort study. In this study, 149 nurses who joined our hospital in 2019 underwent training using workshops combined with the flipped classroom model (experimental group), while 159 nurses who joined the hospital in 2018 received only workshop-based training (control group). The combination of workshops with the flipped classroom training model was divided into two modules: pre-class and in-class training. The participation of nurses in the training activities, on-site assessment of training, nurses' evaluation of their training, and related indicators of tube quality management were evaluated.The average age of nurses in the control group was 22.94 ± 0.94 years and that of nurses in the experimental group was 25.42 ± 3.23 years (The combination of workshop and flipped classroom training is effective in improving tube fixation training of nurses, cultivating nurses' active learning abilities and clinical thinking, and improving the safety of the procedure.

The increasing resistance of plant diseases caused by phytopathogenic fungi highlights the need for highly effective and environmentally benign agents. The antifungal activities of Cnidium monnieri fruit extracts and five isolated compounds as well as structurally related coumarins against five plant pathogenic fungi were evaluated. The acetone extract, which contained the highest amount of five coumarins, showed strongest antifungal activity. Among the coumarin compounds, we found that 4-methoxycoumarin exhibited stronger and broader antifungal activity against five phytopathogenic fungi, and was more potent than osthol. Especially, it could significantly inhibit the growth of Rhizoctonia solani mycelium with an EC50 value of 21 μg mL-1 . Further studies showed that 4-methoxycoumarin affected the structure and function of peroxisomes, inhibited the β-oxidation of fatty acids, decreased the production of ATP and acetyl coenzyme A, and then accumulated ROS by damaging MMP and the mitochondrial function to cause the cell death of R. solani mycelia. 4-Methoxycoumarin presented antifungal efficacy in a concentration- dependent manner in vivo and could be used to prevent the potato black scurf. This study laid the foundation for the future development of 4-methoxycournamin as an alternative and friendly biofungicide.

Context: Calenduloside E (CE), one of the primary natural products found in Aralia elata (Miq.) Seem. (Araliaceae), possesses prominent anti-apoptotic potential. A previous study found that one of the anti-apoptotic CE targets is heat shock protein 90 AB1 (Hsp90AB1) by probe CE-P, while the other targets of CE still need to be identified with more efficient probes. Objective: This study investigates CE analogue (CEA) as one clickable activity-based probe for use in exploring anti-apoptotic CE targets. Materials and methods: Pretreatment of HUVECs with CEA (1.25 μM) for 8 hr, followed by ox-LDL stimulation for 24 h. Flow cytometry analysis and JC-1 staining assays were performed The kinetic constant measurements were tested by the Biacore T200, CM5 Sensor Chip which was activated by using sulpho-NHS/EDC. Ligands were dissolved and injected with a concentration of 12.5, 6.25, 3.125, 1.56, 0.78 and 0 μM. Results: CEA was confirmed to possess an anti-apoptotic effect. The probable targets of CE/CEA were calculated, and as one of the higher scores proteins (Fit values: 0.88/0.86), Hsp90 properly got our attention. Molecular modelling study showed that both CE and CEA could bind to Hsp90 with the similar interaction, and the docking scores (S value) were −7.61 and −7.33. SPR assay provided more evidence to prove that CEA can interact with Hsp90 with the KD value 11.7 µM. Discussion and conclusions: Our results suggest that clickable probe CEA could alleviate ox-LDL induced apoptosis by a similar mechanism of anti-apoptotic CE, and afforded the possibility of identifying additional anti-apoptotic targets of CE.

Intervertebral disc degeneration (IDD) leads to low back pain (LBP). This study aimed to determine the regulation of IDD by competing endogenous RNAs (ceRNAs). We obtained the GSE63492, GSE124272, and GSE129789 datasets from the Gene Expression Omnibus database. The changes of long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and mRNAs in IDD were characterized. The significantly changed mRNAs were subjected to protein-protein interaction analysis using the STRING database, and its functions and involved pathways were analyzed using the DAVID database and gene set enrichment analysis (GSEA). The significant changed lncRNAs, miRNAs and mRNAs were linked in a ceRNA network based on their interactions - predicted by Starbase and miRWalk. Differentially methylated loci of significantly changed mRNAs in early and advanced IDD were compared using the GSE129789 dataset. We identified 245 significantly changed mRNAs, 133 lncRNAs, and 228 miRNAs between patients with IDD and normal individuals. GSEA suggested that 17 pathways related to cell proliferation were activated while 35 cell signaling and immune-related pathways were suppressed in IDD. The following ceRNA network in IDD was built: LINC00665/hsa-miR-7-5p/FZD3, ZNF549; LINC00665/hsa-let-7e-5p/FZD3, ACVR2B; TRG-AS1/hsa-miR-574-5p/ACVR2B, P3H2; TRG-AS1/ hsa-let-7e-5p/FZD3, ACVR2B; and ZNF571-AS1/let-7e-5p/ACVR2B, FZD3. A lncRNA-miRNAmRNA ceRNA network which might regulate the progression of IDD was developed.

An asymmetric synthesis of 14-methyl-1-octadecene, the sex pheromone of the peach leafminer moth, has been efficiently achieved. A key chiral intermediate, ( R)−4-(benzyloxy)−3-methylbutanal, which has been developed as the resource chemical, can be obtained in large quantities from the steroid industry. 1,11-Undecanediol is selectively masked, and then converted into a phosphonium salt derivative, thereby effectively constructing a carbon skeleton. The target molecule is synthesized in 8 linear steps, with a 42% yield. The key characteristic of our synthesis lies in its chiral-pool strategy.

Pleurotus tuoliensis is a valuable, rare and edible mushroom that is been commercially cultivated and is rapidly developing in China markets. Low temperatures are required to induces primordia initiation for the successful production of fruiting bodies (basidiomes) during commercial cultivation. In this work, we investigated the enzymatic activities and performed transcription profiling analysis of enzymatic genes under different low temperature conditions. The results suggest that the enzymatic activities and transcription levels decrease or increase significantly at 4 and 13 °C. Lacc10 and mnp6 seems to play a dominant role during nutrition growth. Furthermore, the expression of laccase and peroxidase genes was highly correlated to the detected extracellular enzymatic activity. Cold stress genes expression profiles were upregulated under 4 °C/13 °C (3 days), while only the Hsp70 gene was downregulated (at the stage of fruiting bodies production) at 13 °C (12 days). Our results showed that the transcriptional regulation of laccase and ligninolytic peroxidase genes plays an important role in the fruiting bodies of Bailinggu under low temperature induction (4 °C). Induction at low temperatures was a highly important cultivation condition in Bailinggu.

Continuous cropping obstacles severely hindered the sustained development of the ginseng industry. Among the obstacles, an imbalance of soil microbiome community was considered one of the major culprits. The fungal community is an essential part of the soil microbiome community. Extensive characterization of the fungal community composition and variation during ginseng cultivation will help us understand the mechanism underlying continuous cropping obstacles. By using a high-throughput amplicon sequencing method, the non-rhizospheric fungal community of farmland cultivated ginseng of 2 years old (C2) and 5 years old (C5), understory wild ginseng of 15 years old (W15) and 35 years old (W35), fallow fields which have been abandoned for 10 (F10) years were characterized. Farmland cultivated ginseng and understory wild ginseng harbored distinct non-rhizospheric fungal communities, and extension of cultivation periods enlarged the fungal community difference between two cultivation modes. Extended cultivation periods significantly decreased the OTU richness and PD whole tree indices, and OTU number and cultivation periods were negatively correlated. Extension of cultivation periods led to an increased abundance of pathotrophs. Still, the increased abundance of pathotrophs may not be the leading cause of severe continuous cropping obstacles in farmland cultivated ginseng. Compared with understory wild ginseng, farmland cultivated ginseng had a lower abundance of symbiotrophs and a higher abundance of saprotrophs. This changed symbiotrophs/saprotrophs ratio may have some correlation with the severe continuous cropping obstacles that occurred in farmland cultivated ginseng. Fallowing on the fungal community of the non-rhizosphere soil was generally opposite of that of extension of ginseng cultivation periods. The impacts of farmland cultivation on the fungal community of the non-rhizosphere soil can last for decades, even if the following is practiced.

We investigated whether Xiao-Xu-Ming decoction reduced mitophagy activation and kept mitochondrial function in cerebral ischemia-reperfusion injury. Rats were randomly divided into 5 groups: sham, ischemia and reperfusion (IR), IR plus XXMD (60 g/kg/day) (XXMD60), IR plus cyclosporin A (10 mg/kg/day) (CsA), and IR plus vehicle (Vehicle). Focal cerebral ischemia and reperfusion models were induced by middle cerebral artery occlusion (MCAO). Cerebral infarct areas were measured by triphenyl tetrazolium chloride staining. Cerebral ischemic injury was evaluated by hematoxylin and eosin staining (HE) and Nissl staining. Ultrastructural features of mitochondria and mitophagy in the penumbra of the ischemic cortex were observed by transmission electron microscopy. Mitophagy was detected by immunofluorescence labeled with LC3B and VDAC1. Autophagy lysosome formation was observed by immunofluorescence labeled with LC3B and Lamp1. The expression of LC3B, Beclin1, and Lamp1 was analyzed by Western blot. The rats subjected to MCAO showed worsened neurological score and cell ischemic damage. These were all significantly reversed by XXMD or CsA. Moreover, XXMD/CsA notably downregulated mitophagy and reduced the increase in LC3, Beclin1, and Lamp1 expression induced by cerebral ischemia and reperfusion. The findings demonstrated that XXMD exerted neuroprotective effect via downregulating LC3, Beclin1, Lamp1, and mitochondrial p62 expression level, thus leading to the inhibition of mitophagy.

Silk porous scaffolds have shown promising applications in tissue regenerations as cellular scaffolds to incorporate cells in vitro and in vivo, and facilitate cell proliferation and production of extracellular matrix. It remains strong needs to optimize the microstructures and performances of silk scaffolds for better biocompatibility. Here, a green process was developed to form water-insoluble scaffolds. Repeated freezing-dissolving procedures and silk nanofibers were introduced to tune the performances of the scaffolds, resulting in amorphous conformations and nanofibrous structures. Controllable degradation and mechanical properties as well as improved cell compatibility were then achieved for these scaffolds, suggesting their promising future in tissue regenerations. Our present results confirmed the possibility of actively designing silk scaffolds with preferable properties used in various tissue regenerations.

Rhubarb is commonly used as laxatives in Asian countries, of which anthraquinones are the major active ingredients, but there are an increased number of concerns regarding the nephrotoxicity of anthraquinones. In this study, we compared the pharmacokinetic characteristics of rhubarb anthraquinones in rats after orally administered with rhubarb and rhubarb total free anthraquinone oral colon-specific drug delivery granules (RTFA-OCDD-GN), and then explained why these granules could reduce the nephrotoxicity of anthraquinones when they produced purgative efficacy. A sensitive and reliable high performance liquid chromatography (HPLC) method has been fully validated for simultaneous determination of the five active components of rhubarb, and successfully applied to investigate and compare the remarkable differences in pharmacokinetic study of rhubarb anthraquinones after orally administered with rhubarb and RTFA-OCDD-GN. The results showed that, compared with rhubarb group, the AUC, Cmax, t1/2z and Vz/F of aloe-emodin, rhein, emodin and chrysophanol in rats receiving the RTFA-OCDD-GN were significantly decreased, and the Tmax of the four analytes was prolonged. Moreover, the Tmax of rhein, the Cmax of chrysophanol and emodin all have significant differences (P

This paper concerns the simulation of Mode I fracture with a local concrete damage model in explicit finite element code LSDYNA. A reliable modeling of fracture is essential in the analysis of tension-dominated problems, as well as the prediction of concrete damage due to cracking. A special focus of this paper is placed on an effective representation of the tensile localization in finite element modeling while generalized macro material properties are employed to modeling meso-scale problems. An investigation into the use of a typical damage plasticity concrete model within LSDYNA Explicit, based on the crack band theory, is described in detail. The main focus of the current paper is on the tensile softening branch.

The role of AMP-activated protein kinase (AMPK) in the regulation of energy metabolism and the control of skeletal muscle regeneration post injury has been described previously. It remains unknown whether this metabolic sensor plays a role in the mechanism of axonal regeneration post injury. In this study, we used a sciatic nerve crushed mouse model to detect the expression of AMPK in sciatic nerve and spinal motor neurons at 1 week, 2 weeks and 3 weeks after injury by immunofluorescence staining. Electrophysiological and histopathological studies were used to confirm the nerve injury and regeneration. Our results showed that frequency of AMPK-positive spinal motor neurons was significantly higher on day 7 after sciatic nerve crush (SNC) and peaked on day 14. No expression of AMPK was detected in axons of the sciatic nerve before and after the injury. Taken together, our study suggested a possible role of AMPK in the mechanism of motor nerve regeneration after injury. Keywords: Sciatic nerve injury, Motor neuron, AMP-Activated protein kinase

Transmission lines pass through various types of regions in China and some of that are corrosive. The foundation concrete of transmission lines in corrosive environments had shown serious deterioration, which usually caused by concrete deterioration, rebar corrosion, degradation of bond strength between rebar and concrete due to various corrosive effects. There are salt lake areas in west China where some power transmission channels pass through. Field tests are carried out in Golmud area to research the durability of foundation concrete of transmission lines. And test results show that the concrete strength in the air is higher than underground and the carbonation depth of the foundation concrete decreases with the increase of concrete compressive strength.

Aiming at the disadvantage of existing equipment maintenance accessibility evaluation method, this paper studied the project of equipment maintenance accessibility evaluation. a method of equipment maintenance accessibility evaluation in the virtual environment is put forward based on Matrices Permanent and index correlation degree , at last an example is given. It is significant for developing maintainability verification and increasing Equipment Maintainability in the course of equipment digital mock-up designing.

Aiming at the disadvantage of existing equipment MTTR demonstration method, this paper studied the project of equipment maintainability demonstration Based on Virtual Simulation, and put forward a method of equipment MTTR demonstration in the virtual environment, at last power system of equipment is verified as an example. It is significant for developing maintainability demonstration and increasing Equipment maintainability in the course of equipment digital mock-up designing.

Aiming to lack for the verification method of equipment maintainability quantitative requirements, this paper researched the verification method of average replacement time through virtual simulation technology, and proposed the mathematical model of average replacement time, which can lay the foundation for maintainability virtual verification.

Aiming at the disadvantage of existing materiel maintainability quantitative requirements demonstration method, this paper studied the project of the materiel maintainability qualitative requirement demonstration Based on virtual simulation, in order to determine the materiel maintainability qualitative requirement, the accessibility and visibility as an example to illustrate the virtual demonstration method. It is significant for developing maintainability demonstration and increasing materiel maintainability in the course of materiel digital mock-up designing.

KEY MESSAGE : We show for the first time that intraspecific crossing may impact mobility of the prominent endogenous retrotransposon Tos17 under tissue culture conditions in rice. Tos17, an endogenous copia retrotransposon of rice, is transpositionally active in tissue culture. To study whether there exists fundamental genotypic difference in the tissue culture-induced mobility of Tos17, and if so, whether the difference is under genetic and/or epigenetic control, we conducted this investigation. We show that dramatic difference in tissue culture-induced Tos17 mobility exists among different rice pure-line cultivars sharing the same maternal parent: of the three lines studied that harbor Tos17, two showed mobilization of Tos17, which accrued in proportion to subculture duration, while the third line showed total quiescence (immobility) of the element and the fourth line did not contain the element. In reciprocal F1 hybrids between Tos17-mobile and -immobile (or absence) parental lines, immobility was dominant over mobility. In reciprocal F1 hybrids between both Tos17-mobile parental lines, an additive or synergistic effect on mobility of the element was noticed. In both types of reciprocal F1 hybrids, clear difference in the extent of Tos17 mobility was noted between crossing directions. Given that all lines share the same maternal parent, this observation indicates the existence of epigenetic parent-of-origin effect. We conclude that the tissue culture-induced mobility of Tos17 in rice is under complex genetic and epigenetic control, which can be either enhanced or repressed by intraspecific genetic crossing.

Al-Li alloy 2198-T8 was used in the fuselage application. Integral fuselage panels were joined by double friction stir welds. Fatigue tests were conducted in the R=0.1. Notch was made between two welds. Residual stresses were measured and analyzed in the test samples with double welds. Cracks grew from the centre of two welds and across the two welds were observed, and crack growth rates were measured and compared with parent material. It is shown that crack growth rates are lower between double welds, and it is close to parent material after cross the two welds. The virtual crack closure technique (VCCT) method was used to calculate stress intensity factor from residual stress (Kres) in aim to explain the experimental findings.

In this work, Compact-Tension (C(T)) specimens with transverse welds in the sample centre were designed. The residual stress distributions were measured parallel and perpendicular to the weld nugget. Fatigue crack growth (FCG) rates were measured in the lab air. It is shown that compressive residual stresses around notch have significant effect on FCG rates and the effect deceases with crack growing. FCG rate is lower in the nugget than in parent material. Effects of residual stress were studied with crack growing. The lower crack growth rate in nugget is believed to be linked in part to compressive residual stress, but also in part to a microstructure effect present when crack grows in the recrystallized nugget.

In this work, CrN/NbN nanometer multi-layers were deposited on the metal substrates by a dual-target DC reactive magnetron sputtering system. X-ray diffraction, Scanning Electron Microscope and Energy Dispersive Spectrometer were used to analysis the phase composition, crystal structure, surface morphology, fracture morphology and elemental composition of thin films. Micro Hardness Tester and wear-resistant experiments were used to test the hardness and wear properties of the films.

Telomere and telomerase were closely related to occurrence and development of some cancers. To enhance ability of myricetin moiety for inhibiting telomerase, we designed a series of novel myricetin derivatives based on reasonable analysis. The telomerase inhibition assay showed that compound 6d displayed the most potent inhibitory activity with IC50 value of 0.91 μM. The anticancer activity assay showed that 6d exhibited high activity against human breast cells MDA-MB-231. The docking simulation of compound 6d was performed to get the probable binding model, the results demonstrated that the furan ring inserted into the active site deeply and had hydrophobic interactions with residues of Phe 568, Pro 627, four methoxy groups had hydrophobic interactions with residues of Phe 568, Pro 627, Lys 902, Val 904 and Pro 929. Western blot results showed that expression of p65 and TERT protein was clearly down-regulated by compound 6d. These data support further studies for the rational design of more efficient p65 and TERT modulators.

Traditional Chinese medicine (TCM) and acupuncture has been gradually accepted by the mainstream society since the 1970s and has been rapidly expanding, accompanying the tide of Chinese immigration since the 1980s. Acupuncture legislation has been approved by the governments of 5 provinces in Canada between 1988 and 2014. After the acceptance of self-regulation, 5 corresponding colleges were established, one after another. The code of ethics and professional practice standard were developed by the Colleges. British Columbia (BC) became the first Canadian province to offer acupuncture treatments as a supplementary benefit for its Medical Services Plan premium assistance recipients beginning in 2008. The 5 colleges united to form the Canadian Alliance of Regulatory Bodies of Traditional Chinese Medicine Practitioners and Acupuncturists (CARBTCMPA) in the same year. The Entry-level Occupational Competencies for the Practice of TCM in Canada were developed by CARB-TCMPA in 2010. The Pan-Canadian registration examinations for acupuncturists, herbalists and TCM practitioners have been administered and scheduled since 2013. The Entry-level Occupational Competencies for Doctors of TCM were developed by College of Traditional Chinese Medicine Practitioners and Acupuncturists of British Columbia (CTCMA-BC) in 2014. It sketches the blueprint for future development of the TCM profession in Canada.

A series of novel pyrazole-5-carboxamide and pyrazole-pyrimidine derivatives were designed and synthesized. All compounds have been screened for their antiproliferative activity against MGC-803, SGC-7901 and Bcap-37 cell lines in vitro. The results revealed that compounds 8a, 8c and 8e exhibited strong inhibitory activity against MGC-803 cell line. The flow cytometric analysis result showed that compound 8e could inhibit MGC-803 proliferation. Some title compounds were tested against telomerase, and compound 8e showed the most potent inhibitory activity with IC50 value at 1.02 ± 0.08 μM. The docking simulation of compound 8e was performed to get the probable binding model, among them, LYS 189, LYS 372, LYS 249 and ASP 254 may be the key residues for the telomerase activity.

This paper presents a comprehensive review of the occupational exposure limits (OELs) of chemical substances in China. It provides historical background on the development of OELs in this country, with a complete list of traditionally adopted and newly developed OELs for chemicals in workplaces. The philosophical thoughts, the administrative system, the scientific protocols for setting and amending health standards, with emphasis on making health a basic criterion for setting health standards, strengthening epidemiological studies of the human population, integrating epidemiological and toxicological studies, considering technological and economical feasibilities, and making full use of literature information sources are discussed. Further perspectives with respect to practical issues of maximum allowable concentration and time-weighted average, selection of safety factors, and establishment of biological exposure limits are also considered, with the authors′ contributions to a discussion on these topics.

A series of novel 5-phenyl-N-piperidine ethanone-4,5-dihydropyrazole derivatives as potential telomerase inhibitors were synthesized. The bioassays demonstrated that compounds 4d, 4f, 7a and 7b occupied high antiproliferative activities against SGC-7901, MGC-803 and Bcap-37 cell lines. By a modified TRAP assay, some titled compounds were tested against telomerase, and compound 7b showed the most potent inhibitory activity with IC50 value at 2.00 ± 0.40 μM. The active compound 4d was also docked into the telomerase TERT active site to determine the probable binding model. The results indicated that conserved residues Lys189, Asp254 and Gln308 were important for ligand binding via hydrogen bond interactions.

Somaclonal variation is a common phenomenon associated with plant tissue culture. Microsatellites or simple sequence repeats (SSRs) are ubiquitous components of eukaryotic genomes, and are intrinsically unstable under various stress conditions including tissue culture. Here, we assessed genetic stability of a set of 29 mapped SSR loci in calli and regenerated plants derived from a pair of reciprocal sorghum inter-strain F1 hybrids and their pure line parents. We further measured the steady-state transcripts of a set of nine mismatch repair (MMR)-encoding genes and a DEMETER (DME), a DNA glycosylase domain protein-encoding gene in these lines, and tested for a possible relationship between altered expression of a given MMR or DME gene and the SSR variations. We found that SSR variations occurred in calli and regenerated plants of both the studied pure lines though at sharply different frequencies (20.7 vs. 6.9%), but no variation was detected in calli and regenerated plants of the pair of F1 hybrids. Compared with the donor seed plants, markedly altered expression of all nine studied MMR genes and the DME gene was observed in calli, and more conspicuously, in the regenerated plants. However, only one gene, i.e., MLH3, showed an altered expression pattern that is genotype specific and significantly correlated with the occurrence of SSR instability.

Overexpression of cyclooxygenase (COX)-2 is associated with the progression of various malignancies, but the contribution of COX-2 expression, bioactivity or their cooperation to bladder cancer growth calls for further clarification. In this study, we investigated the inhibitory effect of COX-2 inhibitors, antisense COX-2 nucleotide, and their combination on the growth of bladder cancer cells (5637, 5637-P and 5637-AS). Suppression of either COX-2 expression or activity caused reduced cell proliferation, enhanced cell numbers in G(1) phase, and increased apoptosis; the joint suppression of COX-2 expression and bioactivity enhanced the degree of cell growth inhibition. COX-2 antisense-expressing 5637-AS tumors showed a 41.42+/-3.08% growth inhibition as compared with 5637 controls. Oral administration of indomethacin (3mg/kg) or celecoxib (15 mg/kg) caused tumor growth inhibition by 31.5+/-14.87% or 83.17+/-1.17%, respectively. When COX-2 antisense cDNA and COX-2 inhibitor celecoxib were combined, the tumor growth inhibition rate was further increased up to 88.78+/-3.10%. These results provide evidence that celecoxib has potential therapeutic effect on bladder cancer, and the joint use of COX-2 antisense cDNA with celecoxib may improve their individual therapeutic effect, especially significantly increase the growth inhibitory effect of COX-2 antisense cDNA.