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1.
BMC Plant Biol ; 24(1): 8, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38163903

ABSTRACT

Patchoulol, a valuable compound belonging to the sesquiterpenoid family, is the primary component of patchouli oil produced by Pogostemon cablin (P. cablin). It has a variety of pharmacological and biological activities and is widely used in the medical and cosmetic industries. However, despite its significance, there is a lack of research on the transcriptional modulation of patchoulol biosynthesis.Salicylic acid (SA), is a vital plant hormone that serves as a critical signal molecule and plays an essential role in plant growth and defense. However, to date, no studies have explored the modulation of patchoulol biosynthesis by SA. In our study, we discovered that the application of SA can enhance the production of patchoulol. Utilizing transcriptome analysis of SA-treated P. cablin, we identified a crucial downstream transcription factor, PatWRKY71. The transcription level of PatWRKY71 was significantly increased with the use of SA. Furthermore, our research has revealed that PatWRKY71 was capable of binding to the promoter of PatPTS, ultimately leading to an increase in its expression. When PatWRKY71 was silenced by a virus, the expression of both PatWRKY71 and PatPTS was reduced, resulting in the down-regulation of patchoulol production. Through our studies, we discovered that heterologous expression of PatWRKY71 leads to an increase in the sensitivity of Arabidopsis to salt and Cd, as well as an outbreak of reactive oxygen species (ROS). Additionally, we uncovered the regulatory role of PatWRKY71 in both patchoulol biosynthesis and plant defense response. This discovery provided a theoretical basis for the improvement of the content of patchoulol and the resistance of P. cablin through genetic engineering.


Subject(s)
Arabidopsis , Pogostemon , Sesquiterpenes , Transcription Factors/genetics , Transcription Factors/metabolism , Plants/metabolism , Pogostemon/genetics , Sesquiterpenes/metabolism , Arabidopsis/genetics , Arabidopsis/metabolism
2.
Sensors (Basel) ; 21(21)2021 Oct 20.
Article in English | MEDLINE | ID: mdl-34770269

ABSTRACT

Human activity recognition plays a prominent role in numerous applications like smart homes, elderly healthcare and ambient intelligence. The complexity of human behavior leads to the difficulty of developing an accurate activity recognizer, especially in situations where different activities have similar sensor readings. Accordingly, how to measure the relationships among activities and construct an activity recognizer for better distinguishing the confusing activities remains critical. To this end, we in this study propose a clustering guided hierarchical framework to discriminate on-going human activities. Specifically, we first introduce a clustering-based activity confusion index and exploit it to automatically and quantitatively measure the confusion between activities in a data-driven way instead of relying on the prior domain knowledge. Afterwards, we design a hierarchical activity recognition framework under the guidance of the confusion relationships to reduce the recognition errors between similar activities. Finally, the simulations on the benchmark datasets are evaluated and results show the superiority of the proposed model over its competitors. In addition, we experimentally evaluate the key components of the framework comprehensively, which indicates its flexibility and stability.


Subject(s)
Ambient Intelligence , Human Activities , Aged , Algorithms , Benchmarking , Cluster Analysis , Humans , Recognition, Psychology
3.
Zhongguo Zhong Yao Za Zhi ; 46(8): 2045-2050, 2021 Apr.
Article in Zh | MEDLINE | ID: mdl-33982518

ABSTRACT

In the past few years, continuous manufacturing(CM) has been put forward by the FDA. Pharmaceutical enterprises are encouraged to promote the implementation of CM, which has become a hot research direction of pharmaceutical technology. In February 2019, the FDA issued a draft guideline for the implementation of CM, which greatly promoted the development of CM and provided reference for continuous manufacturing of traditional Chinese medicine(TCM). The production process of TCM is a complex system. With the innovation of production equipment and the promotion of automation and informatization of TCM production, the exis-ting policies, regulations and traditional production control capacity are difficult to meet the market demand for high-quality TCM pro-ducts. In this paper, we reviewed the new technologies and methods of quality control in accordance with the characteristics of TCM production by referring to modern manufacturing technology, information technology and quality control technology. Based on the "QbD" theory and "PAT" technology, process knowledge system(PKS), an advanced control strategy, was proposed to provide a reference for the implementation of CM in TCM production.


Subject(s)
Drugs, Chinese Herbal , Medicine, Chinese Traditional , Commerce , Quality Control , Technology, Pharmaceutical
4.
Nature ; 489(7416): 379-84, 2012 Sep 20.
Article in English | MEDLINE | ID: mdl-22996552

ABSTRACT

The low-temperature states of bosonic fluids exhibit fundamental quantum effects at the macroscopic scale: the best-known examples are Bose-Einstein condensation and superfluidity, which have been tested experimentally in a variety of different systems. When bosons interact, disorder can destroy condensation, leading to a 'Bose glass'. This phase has been very elusive in experiments owing to the absence of any broken symmetry and to the simultaneous absence of a finite energy gap in the spectrum. Here we report the observation of a Bose glass of field-induced magnetic quasiparticles in a doped quantum magnet (bromine-doped dichloro-tetrakis-thiourea-nickel, DTN). The physics of DTN in a magnetic field is equivalent to that of a lattice gas of bosons in the grand canonical ensemble; bromine doping introduces disorder into the hopping and interaction strength of the bosons, leading to their localization into a Bose glass down to zero field, where it becomes an incompressible Mott glass. The transition from the Bose glass (corresponding to a gapless spin liquid) to the Bose-Einstein condensate (corresponding to a magnetically ordered phase) is marked by a universal exponent that governs the scaling of the critical temperature with the applied field, in excellent agreement with theoretical predictions. Our study represents a quantitative experimental account of the universal features of disordered bosons in the grand canonical ensemble.

5.
J Hazard Mater ; 474: 134837, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-38850945

ABSTRACT

Multi-component droplets from daily activities and production processes severely degrade indoor air quality. Their health hazards and removal efficiency depend on size and composition, significantly affected by evaporation and growth. The phase transition process is complex, involving a broad spectrum of droplet sizes with diverse heat and mass transfer characteristics. Components within the droplets experience simultaneous phase transitions at differing rates and mass transfer directions. This study aims to refine the existing evaporation model of single-component droplets in continuous flows by theoretically integrating the effects of varying droplet sizes and multiple components. A multi-component droplet evaporation/growth model that spans the entire range of droplet sizes has been developed, and predictions have been made based on this model. Utilizing MATLAB, this model accurately predicts the indoor dynamics of multi-component droplets, with deviations under 16 % from experiments. It improves accuracy by over 25 % across droplet sizes via dimensionless transfer coefficients and boosts precision by over 24 % for multi-component droplets with zero-diffusion transport. The radius of the droplet after phase change can reach 8.42 × 10-6 m and remains suspended in the air for an extended period. This study establishes a solid theoretical foundation for accurately predicting the indoor distribution of multi-component droplets.

6.
J Hazard Mater ; 476: 135007, 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-38944994

ABSTRACT

Accumulation of cadmium (Cd) in rice is not only harmful to the growth of plants but also poses a threat to human health. Exposure to Cd triggers unfolded protein response (UPR) within cells, a process that is still not completely understood. The study demonstrated that the lack of OsbZIP39, an essential endoplasmic reticulum (ER)-resident regulator of the UPR, resulted in decreased Cd intake and reduced Cd levels in the roots, stems, and grains of rice. Upon exposure to Cd stress, GFP-OsbZIP39 translocated from ER to nucleus, initiating UPR. Further investigation revealed that Cd treatment caused changes in sphingolipid levels in the membrane, influencing the localization and activation of OsbZIP39. Yeast one-hybrid and dual-LUC assays were conducted to validate the interaction between activated OsbZIP39 and the promoter of the defensin-like gene OsCAL2, resulting in an increase in its expression. Different variations were identified in the coding region of OsbZIP39, which may explain the varying levels of Cd accumulation observed in the indica and japonica subspecies. Under Cd treatment, OsbZIP39ind exhibited a more significant enhancement in the transcription of OsCAL2 compared to OsbZIP39jap. Our data suggest that OsbZIP39 positively regulates Cd uptake in rice, offering an encouraging objective for the cultivation of low-Cd rice.


Subject(s)
Cadmium , Endoplasmic Reticulum Stress , Gene Expression Regulation, Plant , Oryza , Plant Proteins , Oryza/metabolism , Oryza/genetics , Oryza/drug effects , Cadmium/toxicity , Cadmium/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Endoplasmic Reticulum Stress/drug effects , Gene Expression Regulation, Plant/drug effects , Defensins/genetics , Defensins/metabolism , Unfolded Protein Response/drug effects , Plant Roots/metabolism , Plant Roots/drug effects
7.
Ying Yong Sheng Tai Xue Bao ; 34(11): 2969-2977, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37997407

ABSTRACT

The application of biochar can improve soil fertility and benefit sustainable agricultural development and carbon neutrality simultaneously. To better understand the effects of biochar addition on nitrogen transformation and N2O emission in a coastal saline-alkali soil and its potential mechanisms, we conducted a 60-day laboratory incubation experiment with six treatments, i.e., ammonium sulfate (N 150 mg·kg-1), ammonium sulfate + 0.4% (weight/weight) biochar, ammonium sulfate + 0.6% biochar, ammonium sulfate + 0.8% biochar, ammonium sulfate + 1.6% biochar, and ammonium sulfate + 0.2% biochar and 0.2% organic fertilizer (based on equivalent N basis). The results showed that soil nitrogen transformation was mainly affected by biochar addition at the early stage of incubation. Biochar addition significantly increased the contents of nitrate and ammonium. Biochar addition significantly increased soil net nitrification rate, but the magnitude of such increases decreased with increasing biochar addition level. Similar temporal change patterns of N2O emissions were observed in all treatments, and the N2O emissions mainly occurred in the first 30 days of incubation. Compared with the CK, biochar addition significantly reduced the cumulative N2O emission, and the decrement increased with increasing biochar addition levels. In conclusion, the effects of biochar and nitrogen fertilizer addition on soil nitrogen transformation and N2O emission varied with the application rate. Biochar addition with a rate of 0.8% (W/W) increased soil inorganic nitrogen content and decreased soil N2O emission. It could provide theoretical basis and reference for the formulation of reasonable plans for the improvement and utilization of biochar in coastal saline-alkali soil.


Subject(s)
Alkalies , Soil , Nitrogen , Fertilizers , Ammonium Sulfate , Nitrous Oxide/analysis , Charcoal , Agriculture/methods
8.
Huan Jing Ke Xue ; 44(10): 5546-5555, 2023 Oct 08.
Article in Zh | MEDLINE | ID: mdl-37827771

ABSTRACT

The release of nitrogen and phosphorus from sediments into lake water will exacerbate the eutrophication of lakes and endanger ecological safety and human health. Microorganisms are indispensable in nitrogen and phosphorus conversion, and accurate analysis of the distribution characteristics and sources of nitrogen and phosphorus in sediments as well as their relationship with microorganisms is an important prerequisite for lake eutrophication control. Taking Taihu Lake as the study area, 30 surface sediment samples were collected, and the grain size, pH, organic matter (OM), dissolved organic carbon (DOC), total phosphorus (TP), total nitrogen (TN), nitrate nitrogen (NO3--N), and dissolved organic nitrogen (DON) along with some other index contents were measured and analyzed; accordingly, spatial distribution characteristics were analyzed. While using nutrient agar (NA), the number of aerobic bacteria (AB) was determined by plate counting in the medium. Combined with principal component analysis (PCA) and Pearson correlation analysis, the spatial distribution characteristics and sources of sediments and AB in Taihu Lake were explored. The characteristics of sediment pollution in Taihu Lake were studied using the comprehensive pollution index and the organic pollution index methods. The results revealed that the average sediment indicators of the surface layer of Taihu Lake were as follows:AB was 9.25×104 CFU·g-1, average particle size (MZ) was 17.59 µm, pH was 7.62, ω(OM) was 15.05 g·kg-1, ω(DOC) was 71.60 mg·kg-1, ω(TP) was 598.13 mg·kg-1, ω(TN) was 1113.92 mg·kg-1, ω(NO3--N) was 3.22 mg·kg-1, and ω(DON) was 22.60 mg·kg-1. The comprehensive pollution index (FF) showed that 13% of the Taihu Lake was moderately polluted, while 87% was heavily polluted. Excluding the area in the center of the lake, the southern lake area, and some lakes in the western part of the East Taihu Lake, TN in the rest of the area was moderately and severely polluted. In addition to the heavy pollution of Zhushan Bay, the TP in Taihu Lake was generally at light and moderate pollution. The organic pollution index (OI) showed that the organic pollution of the sediments of Taihu Lake was relatively light, majorly caused by organic nitrogen (ON) pollution. DOC, DON, TN, and OM in Taihu Lake were primarily derived from the influence of aquatic plants, and TP And AB were primarily derived from the influence of the external input of rivers. This research will provide theoretical support for lake eutrophication treatment and also provide new ideas for further analysis of AB to remove nitrogen and phosphorus pollution from sediments.


Subject(s)
Bacteria, Aerobic , Water Pollutants, Chemical , Humans , Environmental Monitoring , Water Pollutants, Chemical/analysis , Nitrogen/analysis , Phosphorus/analysis , Lakes/chemistry , Eutrophication , Dissolved Organic Matter , China , Geologic Sediments/chemistry
9.
J Hazard Mater ; 421: 126830, 2022 01 05.
Article in English | MEDLINE | ID: mdl-34396975

ABSTRACT

Numerous studies have investigated neurobehavioral toxicity of microplastics, but no studies have illustrated mechanism via brain-gut axis. Here, juvenile discus fish (Symphysodon aequifasciatus) were exposed for 96 h to microfibers (900 µm, fiber, MFs) or nanoplastics (~88 nm, bead, NPs) with three concentrations (0, 20 and 200 µg/L). Accumulation in fish gut was independent of plastics type and concentration. MFs reduced growth performance while NPs weakened swimming and predatory performance of post-exposed discus. For brain cholinesterase activity, acetylcholinesterase was activated by NPs while NPs/MFs exposure inhibited butyrylcholinesterase. Concentrations of neurotransmitters (acetylcholine, dopamine and γ-aminobutyric acid) increased in brain but decreased in gut after NPs or MFs exposure. For gut microbiota, increased richness under MFs exposure was observed. At phylum level, Proteobacteria proportion was lower in NPs but higher in MFs. Abundance of Clostridia and Fusobacteriia (Bacillus), potentially secreting neurotransmitters, increased in NPs but decreased in MFs. Brain transcriptomics revealed seven upregulated and four downregulated genes concerning neural-activities. Pathways of neuroactive ligand-receptor interaction and serotonergic synapse were enriched in both MFs and NPs, but dopaminergic synapse pathway was enriched only in MFs. These results established a novel mechanism by which microplastics might cause behavioral toxicities via brain-gut-microbiota axis.


Subject(s)
Gastrointestinal Microbiome , Plastics , Acetylcholinesterase , Animals , Brain , Butyrylcholinesterase , Microplastics
10.
J Hazard Mater ; 424(Pt D): 127751, 2022 02 15.
Article in English | MEDLINE | ID: mdl-34799162

ABSTRACT

As detriments in aquatic environments, microplastics (MPs) have been commonly studied on organisms, but tissue-scale effects of MPs were poorly understood. Discus fish (Symphysodon aequifasciatus), herewith, were exposed to polystyrene MPs (0/20/200 µg/L) for 28 d. We found that MPs significantly inhibited growth performance. MPs were observed in skin, gill and intestine after 14/28-d exposure. MPs bioaccumulation was independent of exposure time, but increased with MPs concentrations. Microbial community diversity of fish gill, but not skin and intestine, in MPs treatments was significantly increased. Bacterial community of MP-treated skin and gill were obviously separated from control. Skin dominant phyla changed from Actinobacteriota to Proteobacteria and Firmicutes. Proteobacteria gradually occupied dominance in gill after exposure. Furthermore, MPs-induced skin oxidative stress was demonstrated by the activation of superoxide dismutase and catalase. Skin malondialdehyde also increased and showed significant correlations with four bacterial phyla, e.g., Proteobacteria. Gill Na+/K+-ATPase activity decreased, strongly correlating to microbial community changes caused by MPs. Intestinal digestive enzymes activity (pepsin, lipase and α-amylase) reduced, revealing correlation with bacterial community especially Fibrobacterota. These results suggest a tissue-specific effect of MPs to microbial community and biomarkers in aquatic organism.


Subject(s)
Cichlids , Microbiota , Water Pollutants, Chemical , Animals , Biomarkers , Microplastics , Plastics , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
11.
Huan Jing Ke Xue ; 40(2): 859-868, 2019 Feb 08.
Article in Zh | MEDLINE | ID: mdl-30628354

ABSTRACT

Mount Huangshan has a well-preserved ecosystem and obvious differences in vertical geography, which provide a natural laboratory for studying the altitudinal distribution patterns of soil microbial communities in a mid-subtropical forest ecosystem. The soil bacterial community structure and diversity of the samples collected every 100 m from 670 to 1870 m on the south slope of Mount Huangshan were examined using Illumina MiSeq high-throughput sequencing technology. The soil physicochemical properties and soil enzyme activities of the samples were also measured to explore the relationship between bacterial communities and soil properties as well as enzyme activities. The results showed that ① The contents of soil total nitrogen, available nitrogen, total potassium, and total organic carbon were significantly different across the altitudes (P<0.01) and generally increased as altitude increased. The soil sucrase activities across altitudes were significantly different (P<0.01), and generally increased as altitude increased. However, there was no significant difference in acid phosphatase and urease activities between different altitudes (P>0.05). ② The 12 elevational gradients were divided into three groups:low altitude (670-875 m), medium altitude (1080-1370 m), and high altitude (1460-1780 m). The OTUs in low altitude sites were greater than in high altitude sites but lower compared to medium altitude sites. However, the differences in OTUs across altitude sites were not significant. ③ The soil bacterial community diversity showed a unimodal pattern in a small range of altitudes from 875-1370 m, although no apparent trend was observed at the altitudes from 670-1780 m. ④ There were 7 dominant phyla and 15 dominant orders with a relative abundance of more than 3% in all soil samples. ⑤ Correlation heat map analysis between the top 15 bacterial phyla and soil physicochemical properties as well as enzyme activities showed that soil pH had the greatest effect on the differences in soil bacterial community structure across the different altitudes. Pearson correlation analysis and Partial Mantel test also showed that bacterial community α-diversity (P<0.01) and ß-diversity (Partial Mantel r=0.560, P=0.001) were mainly affected by soil pH. Consequently, soil pH was the key environmental factor determining the soil bacterial community structure and diversity across the different altitudes on Mount Huangshan.


Subject(s)
Altitude , Bacteria/classification , Enzymes/metabolism , Forests , Soil Microbiology , Soil/chemistry , Bacteria/enzymology , China
12.
Microsc Res Tech ; 71(1): 11-9, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17902179

ABSTRACT

Halenia elliptica D. Don, a popularly used ethnodrug from Qinghai-Tibetan plateau, was studied to reveal the indispensable morphoanatomic details. The fixed, sectioned, and stained plant materials as well as the epidermis, powder, and maceration materials were studied using light microscope according to the usual microscopic techniques. The results of the microscopic features were systematic described and illustrated. In the root, an endodermal cell was divided into 8-16-22 and 38-50-62 daughter cells in transverse section and in face view, respectively, and 9-11-13 phloem strands were present in primary structure; in the stem, stone cells were observed in the cortex, pericycle, and external phloem while 17-19-21 internal phloem strands were present in an incontinuous ring; in the pedicel, 8-10-12 internal phloem strands were observed to form an incontinuous ring; anisocytic and anomocytic stomata were present in leaf and sepal epidermis; pollen grain was with three germinal apertures and furrows; a few tracheids, a large number of spiral vessels, and various fibers were observed. Also, semiquantitative and quantitative micrographic parameter tables were simultaneously presented. Further, the key authentication parameters were concluded. The study indicated that light microscopy and related techniques could be unambiguously applied to the authentication of Halenia elliptica.


Subject(s)
Gentianaceae/anatomy & histology , Gentianaceae/cytology , Microscopy/methods , Plants, Medicinal/anatomy & histology , Plants, Medicinal/cytology , Flowers/anatomy & histology , Flowers/cytology , Plant Leaves/anatomy & histology , Plant Leaves/cytology , Plant Roots/anatomy & histology , Plant Roots/cytology , Plant Stems/anatomy & histology , Plant Stems/cytology , Tibet
13.
Ying Yong Sheng Tai Xue Bao ; 29(10): 3398-3406, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30325166

ABSTRACT

In agroecosystem, arbuscular mycorrhizal fungi have mutually beneficial symbiosis with roots of many crops. Meanwhile, this special fungal community is also affected by agricultural mana-gements such as fertilization. The objective of this study was to investigate the effects of long-term fertilization managements (no fertilizer, chemical fertilizer, chemical fertilizer combined with straw, chemical fertilizer combined with manure) on arbuscular mycorrhizal fungal community (AM fungal community) in lime concretion black soil, and to identify the indicator species in each fertilization regime. The most dominant arbuscular mycorrhizal fungal phyla in lime concretion black soil were Archaeosporaceae, Diversisporaceae, Gigasporaceae, Claroideoglomeraceae, Glomeraceae and Paraglomeraceae. The genus Paraglomus was strongly and significantly associated with the application of chemical fertilizer and organic fertilizer. Compared with the control, long-term application of chemical fertilizer greatly changed AM fungal community structure and resulted in the decrease of AM fungal diversity, and the addition of wheat straw further decreased the diversity, while the addition of manure could alleviate diversity loss resulted from chemical fertilization. Soil pH and dissolved organic carbon (DOC) were the main factors affecting the changes of AM fungal community. In summary, long-term application of chemical fertilizer combined with different organic materials had different impacts on soil AM fungal community structure and diversity. The combination of chemical fertilizer and manure would be more conducive to the maintenance of AM fungal diversity.


Subject(s)
Mycorrhizae , Agriculture , Calcium Compounds , Crops, Agricultural , Fertilizers , Glomeromycota , Manure , Oxides , Plant Roots , Soil , Soil Microbiology , Symbiosis , Triticum
14.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(10): 1423-1428, 2016 Oct 20.
Article in Zh | MEDLINE | ID: mdl-27777210

ABSTRACT

OBJECTIVE: To observe the effect of RITA, a small molecule that targets p53, combined with temozolomide (TMZ) on proliferation, colony formation and apoptosis of human glioblastoma U87 cells and explore the underlying mechanism. METHODS: Cultured U87 cells were treated with RITA (1, 5, 10, 20 µmol/L), TMZ, or RITA+TMZ (half dose) for 24, 48 or 72 h. MTS assay were used to detect the cell proliferation, and the cell proliferation rate and inhibitory rate were calculated. The effect of combined treatments was evaluated by the q value. The expressions of p53, p21 and other apoptosis-associated genes were detected by qRT-PCR and Western blotting; cell apoptosis was assayed using flow cytometry with Annexin V/PI double staining; colony formation of the cells was detected with crystal violet staining. RESULTS: MTS assay showed that RITA at the 4 doses more potently inhibited U87 cell viability than TMZ at 72 h (P=0.000) with inhibitory rates of 25.94%-41.38% and 3.84%-8.20%, respectively. RITA combined with TMZ caused a more significant inhibition of U87 cells (29.21%-52.11%) than RITA (P<0.01) and TMZ (P=0.000) alone. At the doses above 5 µmol/L, the combined treatments with RITA+TMZ for 48 h resulted in q values exceeding 1.2 and showed an obvious synergistic effect of the drugs. Both RITA and TMZ, especially the latter, significantly increased the expressions of p53, p21, puma, and other apoptosis-associated genes to accelerate apoptosis and inhibit the growth and colony formation of U87 cells, and the effect was more obvious with a combined treatment. CONCLUSION: RITA inhibits the growth of human glioblastoma cells and enhance their sensitivity to TMZ by up-regulating p53 expression, and when combined, RITA and TMZ show a synergistic effect to cause a stronger cell inhibition.


Subject(s)
Dacarbazine/analogs & derivatives , Furans/pharmacology , Glioblastoma/drug therapy , Apoptosis , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival , Dacarbazine/pharmacology , Humans , Temozolomide
15.
Gene Expr ; 10(3): 115-23, 2002.
Article in English | MEDLINE | ID: mdl-12064574

ABSTRACT

The 39-kDa DNA polymerase beta (pol beta) is an essential enzyme in short-patch base excision repair pathway. A wild-type and a truncated forms of pol beta proteins are expressed in primary colorectal and breast adenocarcinomas and in a primary culture of renal cell carcinoma. To test whether pol beta has a contributory role in tumorigenicity of human tumor cell lines, we have undertaken a study to determine expression of pol beta in colon, breast, and prostate tumor cell lines. Unlike primary colon tumor cells, three types of pol beta mRNA have been identified in HCT116, LoVo, and DLD1, colon tumor cell lines. A 111-bp-deleted pol beta transcript was expressed in MCF7, a breast tumor cell line, but not in primary breast tumor cells. An expression of a smaller pol beta transcript has been revealed in DU145, a prostate tumor cell line, whereas, a single base (T) deletion in mRNA at codon 191 was found in prostate cancer tissue. Interestingly, a wild-type pol beta transcript was also expressed in all tumor cell lines similar to primary tumor cells. Furthermore, the cell extract of LoVo exhibited highest gap-filling synthesis function of pol beta when the extract of DU145 showed lowest activity. MNNG, a DNA alkylating agent, enhanced the gap-filling synthesis activity in extracts of LoVo cell line. Furthermore, the cellular viability of LoVo and HCT116 cells is sensitive to MNNG when DU145 cells are resistant. These results demonstrate heterogeneity in pol beta mRNA expression, which may be a risk factor related to tumorigenic activities of tumor cell lines.


Subject(s)
DNA Polymerase beta/genetics , DNA Repair , Neoplasms/genetics , Neoplasms/metabolism , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Cell Survival/drug effects , Colonic Neoplasms/genetics , Colonic Neoplasms/metabolism , DNA Polymerase beta/metabolism , DNA, Neoplasm/metabolism , Female , Gene Expression , Humans , Male , Methylnitronitrosoguanidine/pharmacology , Neoplasms/enzymology , Prostatic Neoplasms/genetics , Prostatic Neoplasms/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Neoplasm/genetics , RNA, Neoplasm/metabolism , Tumor Cells, Cultured , Tumor Stem Cell Assay
16.
Ultrasound Med Biol ; 29(8): 1161-75, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12946519

ABSTRACT

The flat-facet model has been implicitly assumed for the structure of the image surface by most conventional speckle-reduction algorithms. However, this model is rarely found in a real ultrasound (US) image. To preserve the higher order structures and to capture the spatially variant property of the speckle, a new adaptive speckle-reduction algorithm, called the symmetrical speckle-reduction filter (SSRF), was developed based on the slope-facet model. The basic idea of the SSRF was to estimate the uncorrupted signal on the largest symmetrical slope facet centered at each target pixel. The symmetry constraint ensured the correctness of the mean value. An empirical speckle model was incorporated to account for the nature of the speckle in US image. A two-stage despeckling strategy was employed to enhance the statistical reliability of each estimate by forming a union of a set of symmetrical despeckling windows. The proposed SSRF algorithm was compared with two filtered-based and one wavelet-based approaches and the experimental results showed that the proposed SSRF outperformed these three previous approaches in both the synthetic images and the clinical US images tested in this study.


Subject(s)
Image Processing, Computer-Assisted/methods , Ultrasonography/methods , Acoustics , Algorithms , Breast Neoplasms/diagnostic imaging , Female , Humans , Models, Theoretical , Signal Processing, Computer-Assisted , Ultrasonography, Mammary/methods
17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 69(4 Pt 1): 041302, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15169012

ABSTRACT

A three-dimensional granular system fluidized by vertical container vibrations was studied using pulsed field gradient NMR coupled with one-dimensional magnetic resonance imaging. The system consisted of mustard seeds vibrated vertically at 50 Hz, and the number of layers N(l)

18.
J Med Syst ; 36(3): 1809-20, 2012 Jun.
Article in English | MEDLINE | ID: mdl-21184153

ABSTRACT

Endovascular aneurysm repair (EVAR) is an advanced minimally invasive surgical technology that is helpful for reducing patients' recovery time, postoperative morbidity and mortality. This study proposes an ensemble model to predict postoperative morbidity after EVAR. The ensemble model was developed using a training set of consecutive patients who underwent EVAR between 2000 and 2009. All data required for prediction modeling, including patient demographics, preoperative, co-morbidities, and complication as outcome variables, was collected prospectively and entered into a clinical database. A discretization approach was used to categorize numerical values into informative feature space. Then, the Bayesian network (BN), artificial neural network (ANN), and support vector machine (SVM) were adopted as base models, and stacking combined multiple models. The research outcomes consisted of an ensemble model to predict postoperative morbidity after EVAR, the occurrence of postoperative complications prospectively recorded, and the causal effect knowledge by BNs with Markov blanket concept.


Subject(s)
Artificial Intelligence , Heart Diseases/surgery , Postoperative Complications/etiology , Systems Integration , Adolescent , Adult , Aged , Aged, 80 and over , Aneurysm/surgery , Child , Child, Preschool , Endovascular Procedures , Female , Forecasting , Humans , Infant , Male , Middle Aged , Young Adult
19.
Asian Pac J Cancer Prev ; 13(7): 3123-7, 2012.
Article in English | MEDLINE | ID: mdl-22994721

ABSTRACT

OBJECTIVE: Experimental studies have suggested green tea to be a chemopreventive agent for colorectal cancer, and many studies have examined possible associations. However, the conclusions were inconsistent or even contradictory, so we performed a meta-analysis based on published case-control studies to explore if green tea is indeed a protective factor. METHODS: PubMed was searched up to May 10th, 2012 for relevant studies, and references of included studies were manually searched. Finally 13 eligible studies, involving 12,636 cases and 38,419 controls were identified. After data extraction, a meta-analysis was performed using CMA v2 software. RESULTS: The results indicated there may be a weak but not statistically significant reduced risk of colorectal cancer with high dose of green tea intake (OR=0.95, 95% CI:0.81-1.11, p=0.490.69-0.98). This protective effect was also found in all subgroups, except in American and European populations. Sensitivity analysis indicated the result to be robust. Publication bias was not detected by either funnel plot or Egger tests. CONCLUSION: The results of this meta-analysis indicate a weak lower tendency for colorectal cancer development with green tea consumption, but available epidemiologic data are insufficient to conclude that green tea may protect against colorectal cancer in humans.


Subject(s)
Camellia sinensis/chemistry , Colorectal Neoplasms/epidemiology , Plant Extracts/administration & dosage , Tea , Beverages , Case-Control Studies , Colorectal Neoplasms/prevention & control , Humans , Risk
20.
Ying Yong Sheng Tai Xue Bao ; 20(10): 2417-23, 2009 Oct.
Article in Zh | MEDLINE | ID: mdl-20077699

ABSTRACT

An investigation was made on the abundance and diversity of soil fauna in the corn fields under conventional and conservation tillage in Huang-Huai-Hai Plain of China. The abundance and diversity of soil fauna were higher at corn maturing (September) than at its jointing stage (July), and higher at jointing stage under conservation tillage than under conventional tillage. Soil fauna mainly distributed in surface soil layer (0-10 cm), but still had a larger number in 10-20 cm layer under conservation tillage. The individuals of acari, diptera, diplura, and microdrile oligochaetes, especially those of acari, were higher under conservation tillage than under conventional tillage. At maturing stage, an obvious effect of straw-returning under conservation tillage was observed, i. e., the more the straw returned, the higher the abundance of soil fauna, among which, the individuals of collembola, acari, coleopteran, and psocoptera, especially those of collembolan, increased significantly. The abundance of collembola at both jointing and maturing stages was significantly positively correlated with the quantity of straw returned, suggesting that collembola played an important role in straw decomposition and nutrient cycling.


Subject(s)
Ascaris/growth & development , Biodiversity , Invertebrates/classification , Soil , Zea mays/growth & development , Agriculture/methods , Animals , China , Diptera/growth & development , Invertebrates/growth & development , Soil/analysis
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