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MicroRNA-154 functions as a tumor suppressor and directly targets HMGA2 in human non-small cell lung cancer. GENETICS AND MOLECULAR RESEARCH 2016; 15:gmr8173. [PMID: 27173339 DOI: 10.4238/gmr.15028173] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
MicroRNA-154 (miR-154) is dysregulated in some human malignancies and is correlated with tumor progression. However, its expression and function in non-small cell lung cancer (NSCLC) remain unclear. Therefore, we explored the effects of miR-154 on NSCLC tumorigenesis and development. Using quantitative reverse transcription-polymerase chain reaction, we detected miR-154 expression in NSCLC cell lines and primary tumor tissues. The association between miR-154 expression and clinicopathological factors was investigated, and the effects of miR-154 on the biological behavior of NSCLC cells were examined. Ultimately, the potential regulatory effect of miR-154 on high-mobility group A2 protein (HMGA2) expression was confirmed. miR-154 was significantly downregulated in NSCLC cell lines and clinical specimens. Reduced miR-154 expression was significantly associated with lymph node metastasis, advanced TNM stage, and shorter overall survival. Multivariate regression analysis confirmed that downregulation of miR-154 was an independent unfavorable prognostic factor for patients with NSCLC. Overexpression of miR-154 inhibited NSCLC cell proliferation, invasion, and migration, and promoted cell apoptosis in vitro. Furthermore, a luciferase reporter assay identified HMGA2 as a direct target of miR-154. Our findings indicate that miR-154 may act as a tumor suppressor in NSCLC and would serve as a novel therapeutic agent for miR-based therapy.
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Genome sequencing and systems biology analysis of a lipase-producing bacterial strain. GENETICS AND MOLECULAR RESEARCH 2016; 15:gmr7331. [PMID: 27050954 DOI: 10.4238/gmr.15017331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Lipase-producing bacteria are naturally-occurring, industrially-relevant microorganisms that produce lipases, which can be used to synthesize biodiesel from waste oils. The efficiency of lipase expression varies between various microbial strains. Therefore, strains that can produce lipases with high efficiency must be screened, and the conditions of lipase metabolism and optimization of the production process in a given environment must be thoroughly studied. A high efficiency lipase-producing strain was isolated from the sediments of Jinsha River, identified by 16S rRNA sequence analysis as Serratia marcescens, and designated as HS-L5. A schematic diagram of the genome sequence was constructed by high-throughput genome sequencing. A series of genes related to lipid degradation were identified by functional gene annotation through sequence homology analysis. A genome-scale metabolic model of HS-ML5 was constructed using systems biology techniques. The model consisted of 1722 genes and 1567 metabolic reactions. The topological graph of the genome-scale metabolic model was compared to that of conventional metabolic pathways using a visualization software and KEGG database. The basic components and boundaries of the tributyrin degradation subnetwork were determined, and its flux balance analyzed using Matlab and COBRA Toolbox to simulate the effects of different conditions on the catalytic efficiency of lipases produced by HS-ML5. We proved that the catalytic activity of microbial lipases was closely related to the carbon metabolic pathway. As production and catalytic efficiency of lipases varied greatly with the environment, the catalytic efficiency and environmental adaptability of microbial lipases can be improved by proper control of the production conditions.
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Projecting future temperature-related mortality in three largest Australian cities. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 208:66-73. [PMID: 26475058 DOI: 10.1016/j.envpol.2015.09.041] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Revised: 08/03/2015] [Accepted: 09/15/2015] [Indexed: 06/05/2023]
Abstract
We estimated net annual temperature-related mortality in Brisbane, Sydney and Melbourne in Australia using 62 global climate model projections under three IPPC SRES CO2 emission scenarios (A2, A1B and B1). In all cities, all scenarios resulted in increases in summer temperature-related deaths for future decades, and decreases in winter temperature-related deaths. However, Brisbane and Sydney will increase the net annual temperature-related deaths in the future, while a slight decrease will happen in Melbourne. Additionally, temperature-related mortality will largely increase beyond the summer (including January, February, March, November and December) in Brisbane and Sydney, while temperature-related mortality will largely decrease beyond the winter in Melbourne. In conclusion, temperature increases for Australia are expected to result in a decreased burden of cold-related mortality and an increased burden of heat-related mortality, but the balance of these differences varied by city. In particular, the seasonal patterns in temperature-related deaths will be shifted.
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Climate and soil properties limit the positive effects of land use reversion on carbon storage in Eastern Australia. Sci Rep 2015; 5:17866. [PMID: 26639009 PMCID: PMC4671085 DOI: 10.1038/srep17866] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 11/06/2015] [Indexed: 11/19/2022] Open
Abstract
Australia’s “Direct Action” climate change policy relies on purchasing greenhouse gas abatement from projects undertaking approved abatement activities. Management of soil organic carbon (SOC) in agricultural soils is an approved activity, based on the expectation that land use change can deliver significant changes in SOC. However, there are concerns that climate, topography and soil texture will limit changes in SOC stocks. This work analyses data from 1482 sites surveyed across the major agricultural regions of Eastern Australia to determine the relative importance of land use vs. other drivers of SOC. Variation in land use explained only 1.4% of the total variation in SOC, with aridity and soil texture the main regulators of SOC stock under different land uses. Results suggest the greatest potential for increasing SOC stocks in Eastern Australian agricultural regions lies in converting from cropping to pasture on heavy textured soils in the humid regions.
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Abstract
Aniridia is an autosomal dominant disorder characterized by the complete or partial loss of the iris and is almost associated with mutations in the paired box gene 6 (PAX6). We examined three generations of a Chinese family with congenital aniridia and observed genetic defects. Exons of PAX6 from 12 family members were amplified by polymerase chain reaction, sequenced, and compared with reference sequences in NCBI reference sequence database (http://www.ncbi.nlm.nih.gov/nuccore/NG_008679.1?from=5001&to=38170&report=genbank). A rare mutation c.2T>A (M1K) in exon 4 of PAX6 was identified in all affected family members but not in unaffected family members. Our results suggest that the c.2T>A (M1K) mutation may be responsible for the pathogenesis of congenital aniridia in this family. To our knowledge, this is the first report of the M1K mutation in PAX6 in a Chinese family with this disease and the second report worldwide.
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Allelopathy, chemical communication, and plant defense. J Chem Ecol 2013; 15:1193-202. [PMID: 24272004 DOI: 10.1007/bf01014822] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/1988] [Accepted: 05/23/1988] [Indexed: 11/24/2022]
Abstract
Allelopathy is identified particularly with chemical activity between plants; entomologists refer to allelochemicals in a broader context. Recent work shows that several groups of compounds associated with allelopathy also play a part in communication between plants and other organisms. It is argued that such communication is part of the similarities in plant and animal responses to stress and may contribute to plant defense.
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Biologically active secondary metabolites of barley. II. Phytotoxicity of barley allelochemicals. J Chem Ecol 2013; 19:2231-44. [PMID: 24248572 DOI: 10.1007/bf00979660] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The release of alkaloids by barley was quantified by HPLC. Hordenine was released from the roots of barley in a hydroponic system for up to 60 days. The amount reached a maximum, 2μg/plant/day, at 36 days, then declined. Effects on white mustard by hordenine and gramine included reduction of radicle length and apparent reduction in health and vigor of radicle tips. Transmission electron microscopic examination of white mustard radicle tips exposed to hordenine and gramine showed damage to cell walls, increase in both size and number of vacuoles, autophagy, and disorganization of organelles. The evidence of the morphological and primary effects of barley allelochemicals at the levels released by living plants indicates that the biologically active secondary metabolites of barley may lead to a significant role in selfdefense by the crop.
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Outcomes and patterns of secondary relapse in platinum-sensitive ovarian cancer: implications for tertiary cytoreductive surgery. Eur J Surg Oncol 2013; 39:786-91. [PMID: 23490332 DOI: 10.1016/j.ejso.2013.02.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 01/13/2013] [Accepted: 02/01/2013] [Indexed: 12/28/2022] Open
Abstract
AIM To evaluate the outcomes and patterns of patients with secondary relapsed ovarian cancer. METHODS A retrospective study was conducted. The cases comprised 83 patients who underwent tertiary cytoreductive surgery (TCS) followed by chemotherapy, whereas the controls consisted of 76 patients who received chemotherapy alone. RESULTS The median survival was 20 months in 159 patients. Patients with microscopic residual disease after TCS had a median survival of 32.9 months compared with 14.6 months in those with macroscopic residual disease [hazard ratio (HR), 2.82; P = 0.001) and 15.0 months in patients with chemotherapy alone (HR, 2.23; P = 0.001). When stratified by a progression-free interval (PFI) after secondary cytoreduction (SCR), TCS showed no benefit in patients with a PFI ≤12 months or a PFI >12 months compared with those with chemotherapy alone. TCS improved survival in patients with recurrent disease in the pelvis compared with those with recurrent disease in the middle or upper abdomen, with a median survival of 34.9 months and 14.6 months, respectively (HR, 2.94; P = 0.010). However, TCS was not a survival determinant by multivariate analysis. A multivariate analysis identified a PFI after SCR (≤12 mos vs. >12 mos; HR, 2.34; 95% CI, 1.29-4.24; P = 0.005), mesenteric lymph node metastasis at SCR (yes vs. no; HR, 4.18; 95% CI, 1.93-9.03; P < 0.001) and treatment arms at secondary relapse (chemotherapy alone vs. TCS; HR, 1.56; 95% CI, 1.03-2.38; P = 0.037) as independent predictors of survival. CONCLUSIONS Limited survival benefit from tertiary cytoreductive surgery was observed in patients with platinum-sensitive secondary relapsed ovarian cancer.
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Analogous effects of recombinant human full-length amelogenin expressed by Pichia pastoris yeast and enamel matrix derivative in vitro. Cell Prolif 2012; 45:456-65. [PMID: 22834823 DOI: 10.1111/j.1365-2184.2012.00834.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Accepted: 04/09/2012] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVES Amelogenins are proposed to be responsible for enamel matrix derivative (EMD)-induced periodontal regeneration; however, heterogeneity of amelogenins makes it challenging to purify the full-length proteins. This study has been carried out to express and purify a recombinant full-length human amelogenin protein (rHhAm175) in the eukaryotic yeast Pichia pastoris, and further compare biological responses of human periodontal ligament fibroblasts (PDLFs) to rHhAm175 and porcine EMD (pEMD). MATERIALS AND METHODS Human cDNA encoding a 175-amino acid amelogenin was subcloned into the pPIC3.5K vector. The rHhAm175 expressed in P. pastoris GS115 (Mut+) was purified and characterized. We examined cell attachment, migration and proliferation responses of human PDLFs to rHhAm175 and pEMD respectively, and characterized associated changes of proliferation-related intracellular signalling molecules, including extracellular signal response kinase (ERK) and Akt kinases/protein kinase B (Akt/PKB) kinases. RESULTS The purified rHhAm175 was confirmed to be molecular mass 22 021.13 Da, phosphorylated human amelogenin, and alone significantly promoted proliferation and migration of human PDLFs to an extent comparable to that of pEMD. Cell attachment was increased over the first 60 min incubation with rHhAm175 or pEMD. Both rHhAm175 and pEMD induced PDLF mitogenesis via extracellular signal response kinase (ERK1/2), but not by Akt kinases/protein kinase B (Akt/PKB). CONCLUSIONS rHhAm175 modulated cell activities of human PDLFs, to a comparable extent as porcine EMD. These data suggest that rHhAm175 might be used to induce periodontal tissue regeneration.
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Colonic schistosomiasis mimicking submucosal tumor. Endoscopy 2011; 43 Suppl 2 UCTN:E58-9. [PMID: 21287453 DOI: 10.1055/s-0030-1256078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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Coronary heart disease and chronic periodontitis: is polymorphism of interleukin-6 gene the common risk factor in a Chinese population? Oral Dis 2010; 17:270-6. [DOI: 10.1111/j.1601-0825.2010.01736.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Investigating the effect of invasion characteristics on onion thrips (Thysanoptera: Thripidae) populations in onions with a temperature-driven process model. ENVIRONMENTAL ENTOMOLOGY 2009; 38:1575-1584. [PMID: 20021751 DOI: 10.1603/022.038.0608] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A temperature-driven process model was developed to describe the seasonal patterns of populations of onion thrips, Thrips tabaci Lindeman, in onions. The model used daily cohorts (individuals of the same developmental stage and daily age) as the population unit. Stage transitions were modeled as a logistic function of accumulated degree-days to account for variability in development rate among individuals. Daily survival was modeled as a logistic function of daily mean temperature. Parameters for development, survival, and fecundity were estimated from published data. A single invasion event was used to initiate the population process, starting at 1-100 d after onion emergence (DAE) for 10-100 d at the daily rate of 0.001-0.9 adults/plant/d. The model was validated against five observed seasonal patterns of onion thrips populations from two unsprayed sites in the Riverina, New South Wales, Australia, during 2003-2006. Performance of the model was measured by a fit index based on the proportion of variations in observed data explained by the model (R (2)) and the differences in total thrips-days between observed and predicted populations. Satisfactory matching between simulated and observed seasonal patterns was obtained within the ranges of invasion parameters tested. Model best-fit was obtained at invasion starting dates of 6-98 DAE with a daily invasion rate of 0.002-0.2 adults/plant/d and an invasion duration of 30-100 d. Under the best-fit invasion scenarios, the model closely reproduced the observed seasonal patterns, explaining 73-95% of variability in adult and larval densities during population increase periods. The results showed that small invasions of adult thrips followed by a gradual population build-up of thrips within onion crops were sufficient to bring about the observed seasonal patterns of onion thrips populations in onion. Implications of the model on timing of chemical controls are discussed.
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Prevalence and molecular diversity of Archaea in subgingival pockets of periodontitis patients. ACTA ACUST UNITED AC 2009; 24:343-6. [PMID: 19572899 DOI: 10.1111/j.1399-302x.2009.00514.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION The aim of this study was to investigate the prevalence and molecular diversity of Archaea in the subgingival crevices of patients with chronic periodontitis. METHODS Subgingival plaque was collected from 41 patients with chronic periodontitis and 15 healthy subjects. The prevalence of Archaea in those plaque samples was tested by polymerase chain reaction with two broad-range archaeal primer sets. Amplicons from eight Archaea-positive plaque samples were cloned and sequenced for molecular diversity analysis using one of these two primer sets and a novel third primer set. RESULTS Archaea were detected in the subgingival plaque of patients with chronic periodontitis at a prevalence of 70.7-73.2%, but were not detected in healthy subjects. Using one primer set, all sequences of the archaeal amplicons were identified as Methanobrevibacter oralis-like species. With another primer set, the amplicons were also found to be identical to the uncultured M. oralis-like species except one phylotype was found to belong to the class Thermoplasmata. CONCLUSION Archaea might be correlated with periodontal diseases. The diversity of Archaea associated with periodontitis was limited. Almost all sequenced amplicons fell into the genus Methanobrevibacter of the Euryarcheota phylum. M. oralis-like species was the predominant but non-exclusive archaeon in the subgingival dental plaque of patients with periodontitis.
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Second-generation anti-carcinoembryonic antigen designer T cells resist activation-induced cell death, proliferate on tumor contact, secrete cytokines, and exhibit superior antitumor activity in vivo: a preclinical evaluation. Clin Cancer Res 2008; 14:8112-22. [PMID: 19088026 PMCID: PMC2659496 DOI: 10.1158/1078-0432.ccr-07-4910] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
PURPOSE This report describes the development and preclinical qualification tests of second-generation anti-carcinoembryonic (CEA) designer T cells for use in human trials. EXPERIMENTAL DESIGN The progenitor first-generation immunoglobulin-T-cell receptor (IgTCR) that transmits Signal 1-only effectively mediated chimeric immune receptor (CIR)-directed cytotoxicity, but expressor T cells succumbed to activation-induced cell death (AICD). The second-generation CIR (termed "Tandem" for two signals) was designed to transmit TCR Signal 1 and CD28 Signal 2 to render T cells resistant to AICD and provide prolonged antitumor effect in vivo. RESULTS A CIR was created that combines portions of CD28, TCRzeta, and a single chain antibody domain (sFv) specific for CEA into a single molecule (IgCD28TCR). As designed, the gene-modified Tandem T cells exhibit the new property of being resistant to AICD, showing instead an accelerated proliferation on tumor contact. Tandem T cells are more potent than first generation in targeting and lysing CEA+ tumor. Tandem T cells secrete high levels of interleukin-2 and IFNgamma on tumor contact that first-generation T cells lacked, but secretion was exhaustible, suggesting a need for interleukin-2 supplementation in therapy even for these second-generation agents. Finally, second-generation T cells were more effective in suppressing tumor in animal models. CONCLUSION An advanced generation of anti-CEA designer T cells is described with features that promise a more potent and enduring antitumor immune response in vivo. These preclinical data qualify the human use of this agent that is currently undergoing trial in patients with CEA+ cancers.
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[In vitro study on proliferation and multi-lineage differentiation potential of adipose-derived cells]. FEN ZI XI BAO SHENG WU XUE BAO = JOURNAL OF MOLECULAR CELL BIOLOGY 2006; 39:152-62. [PMID: 16944587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Adipose were obtained from patients underwent liposuction treatment (total 19 female donors, 31.5 +/- 5.8 years old). Liposuction tissues were digested with type I collagenase, cells were isolated and cultured up to passage 10. To evaluate the proliferation potential of ADCs, growth curve and cumulative population doubling were achieved by cell counting. CD29,CD105, CD106, CD166, CD49d, CD34, CD31, 3G5 were analyzed by flow cytometry and immunocytochemistry to characterize the cell population. The multi-lineage potential of ADCs was testified by differentiating cells with osteogenic,chondrogenic and adipogenic inducer. A total of 5x10(7) nucleared cells could be obtained from 300ml liposuction tissues. After in vitro cultivation,cumulative population doubling number reached 15.53 at passage 10 (average 1.59 +/- 0.224 /passage). Flow cytometry and immunocytochemistry showed that ADCs expressed high level (>60%) of stem cell-related antigen (CD29, CD105, CD106, CD166), while cells expressed hematopoiesis-related antigen CD34 and CD31 around 7.3% and 29.2% respectively. Collagen II (both in mRNA and protein level) was detected in chondrogenic differentiation. The calcified nodules were observed by von Kossa and Alizarn Red staining and the expressions of AKP and Osteonectin were detected by RT-PCR in osteogenic differentiation. PPARr2, GLU-4, and Leptin genes were detected in adipogenic differentiation and intracellular lipid droplets could be observed by Oil Red staining. ADCs can be abundantly harvested and have high proliferative and multi-lineage differentiation potential.
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Implementation of card: curve-fitting allelochemical response data. NONLINEARITY IN BIOLOGY, TOXICOLOGY, MEDICINE 2005; 3:235-44. [PMID: 19330164 PMCID: PMC2657947 DOI: 10.2201/nonlin.003.02.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Bioassay techniques are essential methods used to study the effects of allelochemicals on plant processes. It is often observed that the biological processes are stimulated at low allelochemical concentrations and inhibited as the concentrations increase. Liu et al., (2003) developed a simple model to fit this type of allelochemical response data. Based on the model, CARD (curve-fitting allelochemical response data) was developed as a Windows based program that can be used to fit a stimulation-inhibition response data. An example of using CARD is given.
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Whole-range assessment: a simple method for analysing allelopathic dose-response data. NONLINEARITY IN BIOLOGY, TOXICOLOGY, MEDICINE 2005; 3:245-59. [PMID: 19330165 PMCID: PMC2657949 DOI: 10.2201/nonlin.003.02.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Based on the typical biological responses of an organism to allelochemicals (hormesis), concepts of whole-range assessment and inhibition index were developed for improved analysis of allelopathic data. Examples of their application are presented using data drawn from the literature. The method is concise and comprehensive, and makes data grouping and multiple comparisons simple, logical, and possible. It improves data interpretation, enhances research outcomes, and is a statistically efficient summary of the plant response profiles.
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Mathematical Modelling of Allelopathy: IV. Assessment of Contributions of Competition and Allelopathy to Interference by Barley. NONLINEARITY IN BIOLOGY, TOXICOLOGY, MEDICINE 2005; 3:213-24. [PMID: 19330162 PMCID: PMC2657951 DOI: 10.2201/nonlin.003.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
One of the main challenges to the research on allelopathy is technically the separation of allelopathic effect from competition, and quantitatively, the assessment of the contribution of each component to overall interference. A simple mathematical model is proposed to calculate the contribution of allelopathy and competition to interference. As an example of applying the quantitative model to interference by barley (Hordeum vulgare cv. Triumph), the approach used was an addition of allelopathic effect, by an equivalent amount, to the environment of the test plant (white mustard, Sinapis alba), rather than elimination of competition. Experiments were conducted in glasshouse to determine the magnitude of the contributions of allelopathy and competition to interference by barley. The leachates of living barley roots significantly reduced the total dry weight of white mustard. The model involved the calculation of adjusted densities to an equivalent basis for modelling the contribution of allelopathy and competition to total interference. The results showed that allelopathy contributed 40%, 37% and 43% to interference by barley at 6, 12 and 18 white mustard pot(-1). The consistency in magnitude of the calculated contribution of allelopathic effect by barley across various densities of receiver plant suggested that the adjusted equivalent density is effective and that the model is able to assess the contribution of each component of interference regardless of the density of receiver plant.
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Mechanics of patterned helical Si springs on Si substrate. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2003; 3:492-495. [PMID: 15002128 DOI: 10.1166/jnn.2003.235] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The elastic response, including the spring constant, of individual Si helical-shape submicron springs, was measured using a tip-cantilever assembly attached to a conventional atomic force microscope. The isolated, four-turn Si springs were fabricated using oblique angle deposition with substrate rotation, also known as the glancing angle deposition, on a templated Si substrate. The response of the structures was modeled using finite elements, and it was shown that the conventional formulae for the spring constant required modifications before they could be used for the loading scheme used in the present experiment.
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[Biological characterization of immortalized porcine chondrocytes by introduction of telomerase]. SHI YAN SHENG WU XUE BAO 2003; 36:435-44. [PMID: 14724934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
The aim of this project was to acquire a clonal immortalized porcine chondrocyte cell line and to determine its biological characterization. Porcine auricle chondrocytes were infected with a retroviral vector pBABE-hTERT followed by selection with 2 micrograms/ml puromycin. RT-PCR and PCR-ELISA performed on separated colonies showed a cell line (TL1) with high and stable ectopic expression of hTERT. The growth curve, HE staining, flow cytometry, and tumorigenicity were analyzed to define the biological characterization of the immortalized chondrocytes. TL1 cells showed an increase in cellular viability and the reduction in apoptosis. But there was no malignant transformation and tumor development in nude mice. The changes of chondrocyte marker expression in this cell line revealed that it remained unstable phenotype. So high ectopic expression of hTERT is able to extend the life span of chondrocytes, but it unable to keep their differentiated phenotype during serial monolayer culture in vitro.
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Mathematical Modeling of Allelopathy. III. A Model for Curve-Fitting Allelochemical Dose Responses. NONLINEARITY IN BIOLOGY, TOXICOLOGY, MEDICINE 2003; 1:37-50. [PMID: 19330111 PMCID: PMC2651613 DOI: 10.1080/15401420390844456] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Bioassay techniques are often used to study the effects of allelochemicals on plant processes, and it is generally observed that the processes are stimulated at low allelochemical concentrations and inhibited as the concentrations increase. A simple empirical model is presented to analyze this type of response. The stimulation-inhibition properties of allelochemical-dose responses can be described by the parameters in the model. The indices, p% reductions, are calculated to assess the allelochemical effects. The model is compared with experimental data for the response of lettuce seedling growth to Centaurepensin, the olfactory response of weevil larvae to alpha-terpineol, and the responses of annual ryegrass (Lolium multiflorum Lam.), creeping red fescue (Festuca rubra L., cv. Ensylva), Kentucky bluegrass (Poa pratensis L., cv. Kenblue), perennial ryegrass (L. perenne L., cv. Manhattan), and Rebel tall fescue (F. arundinacea Schreb) seedling growth to leachates of Rebel and Kentucky 31 tall fescue. The results show that the model gives a good description to observations and can be used to fit a wide range of dose responses. Assessments of the effects of leachates of Rebel and Kentucky 31 tall fescue clearly differentiate the properties of the allelopathic sources and the relative sensitivities of indicators such as the length of root and leaf.
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Production, purification, and characterization of an intracellular aflatoxin-detoxifizyme from Armillariella tabescens (E-20). Food Chem Toxicol 2001; 39:461-6. [PMID: 11313112 DOI: 10.1016/s0278-6915(00)00161-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Some Armillariella tabescens (E-20) multienzymes have previously been reported to present detoxifying activities against aflatoxins. In this paper, we describe the isolation purification of an intracellular enzyme, named aflatoxin-detoxifizyme, which exhibited detoxification activity on aflatoxin B(1) (AFB(1)). This aflatoxin-detoxifizyme exhibited a specific activity of 7.09 nmol min/mg at pH 6.0 and 28 degrees C. The apparent molecular mass was 51.8 kDa as determined by SDS-PAGE. The isoelectric point was estimated to be 5.4 and optimum activity for the enzyme was found at pH 6.8 and 35 degrees C. The activity of the purified enzyme was confirmed by Ames test.
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A k-space method for large-scale models of wave propagation in tissue. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2001; 48:341-54. [PMID: 11370348 DOI: 10.1109/58.911717] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Large-scale simulation of ultrasonic pulse propagation in inhomogeneous tissue is important for the study of ultrasound-tissue interaction as well as for development of new imaging methods. Typical scales of interest span hundreds of wavelengths; most current two-dimensional methods, such as finite-difference and finite-element methods, are unable to compute propagation on this scale with the efficiency needed for imaging studies. Furthermore, for most available methods of simulating ultrasonic propagation, large-scale, three-dimensional computations of ultrasonic scattering are infeasible. Some of these difficulties have been overcome by previous pseudospectral and k-space methods, which allow substantial portions of the necessary computations to be executed using fast Fourier transforms. This paper presents a simplified derivation of the k-space method for a medium of variable sound speed and density; the derivation clearly shows the relationship of this k-space method to both past k-space methods and pseudospectral methods. In the present method, the spatial differential equations are solved by a simple Fourier transform method, and temporal iteration is performed using a k-t space propagator. The temporal iteration procedure is shown to be exact for homogeneous media, unconditionally stable for "slow" (c(x) < or = c0) media, and highly accurate for general weakly scattering media. The applicability of the k-space method to large-scale soft tissue modeling is shown by simulating two-dimensional propagation of an incident plane wave through several tissue-mimicking cylinders as well as a model chest wall cross section. A three-dimensional implementation of the k-space method is also employed for the example problem of propagation through a tissue-mimicking sphere. Numerical results indicate that the k-space method is accurate for large-scale soft tissue computations with much greater efficiency than that of an analogous leapfrog pseudospectral method or a 2-4 finite difference time-domain method. However, numerical results also indicate that the k-space method is less accurate than the finite-difference method for a high contrast scatterer with bone-like properties, although qualitative results can still be obtained by the k-space method with high efficiency. Possible extensions to the method, including representation of absorption effects, absorbing boundary conditions, elastic-wave propagation, and acoustic nonlinearity, are discussed.
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Abstract
In this study we analyzed the different alpha1-adrenoceptor (AR) subtypes present in human saphenous vein (HSV) using reverse transcription polymerase chain reaction (RT-PCR), DNA-DNA hybridization analysis and functional affinities for alpha-AR antagonists. DNA-DNA hybridization analysis of RT-PCR amplification products confirmed the presence of alpha1A- and alpha1B-ARs, and low levels of alpha1D-AR in HSV. The functional results showed: (1) prazosin, the selective alpha1-AR antagonist, phentolamine, the alpha1- and alpha2-ARs antagonist, WB 4101 and 5-MU, the selective alpha1A-AR subtype antagonists were potent, competitive antagonists of noradrenaline (NA)-induced contraction (pA2 values of 11.03, 8.06, 9.02 and 8.34, respectively). (2) Alpha1-AR-induced contraction was sensitive to the alkylating effects of CEC (the alpha1B and alpha1D-AR subtypes antagonist) and (3) The selective alpha1D-AR subtype antagonist BMY displayed low affinity (pA2 values of 6.44). This indicates that the contractile response of the HSV to alpha1-AR-induced is predominantly mediated by both alpha1A and alpha1B-AR subtypes. This was also supported by the good relationship between pA2 values from the present study and reported binding affinities (pKi) values of various alpha1-AR subtype antagonists with cloned human alpha1A- and alpha1B-AR subtypes (r=0.89 and r=0.98, respectively), but not the alpha1D-AR subtype (r=0.67). Our results indicate that alpha1A- and alpha1B-ARs are the main functional and expressed receptor subtypes in HSV.
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Effects of micromolar concentrations of manganese, copper, and zinc on alpha1-adrenoceptor-mediating contraction in rat aorta. Biol Trace Elem Res 2001; 82:159-66. [PMID: 11697764 DOI: 10.1385/bter:82:1-3:159] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2000] [Accepted: 12/28/2000] [Indexed: 11/11/2022]
Abstract
To determine the influences of the Mn, Cu, and Zn on alpha1-adrenoceptor (AR)-mediated vasoconstriction, we investigated their effects on vasoconstriction produced by the alpha1-AR agonist phenylephrine in isolated rings of rat thoracic aorta. The cumulative concentration-contraction curves for phenylephrine were obtained in the absence and presence of Mn (0.3, 1, 3 microM), Cu (1, 10, 16 microM), and Zn (0.3, 1, 10 microM). Mn, Cu, and Zn each inhibited phenylephrine-mediated contraction in a dose-dependent manner. The maximal phenylephrine-induced contraction was significantly reduced by the pretreatment of the arterial rings with 10 and 16 microM Cu (p<0.05). The results suggest that variations in the plasma concentrations of metal might lead to changes in alpha1-AR-mediated constrictive response.
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[Determination of ferulic acid in chuanxiong and in animal serum and cerebrospinal fluid by reversed-phase high performance liquid chromatography]. Se Pu 2000; 18:518-20. [PMID: 12541738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023] Open
Abstract
An easy, rapid and sensitive method for the determination of ferulic acid(FA) in Chuanxiong extracts, animal (mouse) serum and cerebrospinal fluid by RP-HPLC has been developed. The FA was separated on an ODS column, Nova-Pak C18(3.9 mm i.d. x 150 mm) and detected at the wavelength of 320 nm. The mobile phase was methanol-water-acetic acid (35:65:0.5, V/V), with a flow rate of 0.8 mL/min. The detection limit of FA was 1.7 micrograms/L(S/N = 3) and the calibration curve was linear within the range of 0.85 mg/L-4.00 mg/L(r = 0.99904, n = 6). The mean recovery from animal serum and cerebrospinal was 95%-102%.
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[Importance of the posterior and lateral arterial network of elbow on the super-regional and mutual-pedicled axial flap]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 2000; 14:200-4. [PMID: 12078300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
OBJECTIVE To explore the importance of the posterior and lateral arterial network of elbow in the application of the super-regional and mutual-pedicled axial flap. METHODS Twenty-seven upper extremities of adult cadavers were prepared as casts of Acrylomintril Batradiene Styrene(ABS) resin and corroded in a strong solution of NaOH according to natural layers of human tissue. The source, site and structure of the posterior and lateral arterial network of elbow were observed, the number and total sectional area of anastomosing branches crossing the line between two humeral epicondyles were measured and compared with the medial and anterior region. RESULTS There are 8.64 +/- 2.74(36.42%) and 8.30 +/- 1.19(35.0%) anastomosing branches crossing the posterior and lateral regions, and total section areas are (0.48 +/- 0.11) mm2 and (0.37 +/- 0.03) mm2 respectively. So there is very rich arterial network around the elbow. CONCLUSION The enough number of anastomosing branches and their section areas of the posterior and lateral region of the elbow make it possible to connect super-regional and mutual-pedicled axial flaps crossing the elbow.
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Laser Doppler perfusion imaging: new technique for determination of perfusion and reperfusion of splanchnic organs and tumor tissue. Lasers Surg Med Suppl 2000; 20:473-9. [PMID: 9142689 DOI: 10.1002/(sici)1096-9101(1997)20:4<473::aid-lsm15>3.0.co;2-c] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND OBJECTIVE Several investigations indicated that laser Doppler flowmetry on the liver surface reflects relative changes of the total liver blood flow. In this study, Laser Doppler Perfusion Imaging (LDI), monitoring the surface only, was used for measurements of tissue perfusion of normal and/or impaired liver, pancreas, spleen, stomach and intestines, and the blood flow of hepatic tumors in rats. STUDY DESIGN/MATERIALS AND METHODS Eighty Wistar/Furth rats were divided into five groups. Group I served as controls. Groups II and III underwent ischemic injury of the liver and intestine with or without the administration of WEB2170, a platelet-activating factor receptor antagonist. Laser-induced photodynamic therapy (PDT) utilizing delta-amino levulinic acid sensitization was performed in Groups IV and V. RESULTS Normal pancreas and intestine had a high LDI perfusion value and the liver and stomach exhibited a medium perfusion value whereas the perfusion value from the spleen was low. WEB2170 improved the reperfusion of the postischemic liver and intestine. An immediate decrease in surface blood flow of hepatic tissue treated by laser-induced PDT and a decreased blood flow in large tumors were observed. CONCLUSION LDI is a useful technique for the measurement of tissue perfusion of various splanchnic organs or tumor tissues.
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[Determination of furostanol saponins in Bulbus Allii Macroste]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2000; 25:357-9. [PMID: 12512424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To establish an Ehrlich reaction-colorimetry method for determining furostanol saponins in Bulbus Allii Macroste. METHOD Based on the coloration reaction between furostanol saponins and p-dimethylaminobenzaldehyde, the UV detection wavelength used was 515 nm, and the optimum conditions were selected on homogeneous design principle. RESULT The standard curve of macrostemonoside G was linear in the concentration range of 0.1975-0.9880 mg.ml-1. The average recovery was 97.7% (RSD = 3.65%). CONCLUSION The method is rapid, accurate and easy to operate.
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81
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[Determination of tetramethylpyrazine in animal serum and cerebrospinal fluid by high performance liquid chromatography]. Se Pu 2000; 18:46-8. [PMID: 12541454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023] Open
Abstract
A reversed-phase high performance liquid chromatographic (RP-HPLC) method for the determination of the tetramethylpyrazine(TMP) in Chuanxiong extract, the animal(mouse) serum and cerebrospinal fluid has been developed. The TMP was separated on an ODS column Zorbax SB-C18(4.6 mm i.d. x 250 mm, 5 microns) at room temperature and detected by using UV detector at 270 nm. The mobile phase was methanol-water (50:50, V/V) containing 0.2 mmol/L of NH4H2PO4 flowing at a rate of 0.8 mL/min and 20 microL samples were injected. The detection limit of TMP was 1 mg/L and the calibration curve is linear between 5 and 500 mg/L with a correlation coefficient (r) of 0.999. The recovery of TMP ranged 98%-103%. The extract of Chuanxiong and pretreated serum and cerebrospinal fluid sample are stable for a week at room temperature.
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82
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[Transposition of expanded superficial cervical artery skin flaps for the repair of cicatricial contracture of neck]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 1999; 13:235-6. [PMID: 12080807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
OBJECTIVE In order to reduce the complication of the transposition of superficial cervical artery skin flap for the repair of neck defect, the method of pre-expanded skin flap was designed, and its clinical result was observed. METHODS From March 1995 to October 1997, 12 cases with cicatricial contracture of the neck were treated by the following methods, preexpanded superficial cervical artery skin flap, and then transposed it for the reconstruction the cervical scar after burns. There were 8 males and 4 females and the age ranged from 6 to 32 years. A maximal size of flap was 35 cm x 14 cm and a minimal size was 16 cm x 7 cm. RESULTS All the flaps were survived except one, which partial necrosis occurred in the tip. Postoperative follow-up for 6 months to 3 years showed that the physiological angle of cervico-mandibular angle was recovered and the appearance of flap was satisfactory without swelling and contracture. CONCLUSION The preexpanded superficial cervical artery skin flap has many advantages, and it is particularly suitable for reconstruction of severe cervical contracture after extensive burns.
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Screening of the fungus whose multienzyme system has catalytic detoxification activity towards aflatoxin B1 (Part I). Ann N Y Acad Sci 1998; 864:579-85. [PMID: 9928143 DOI: 10.1111/j.1749-6632.1998.tb10385.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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84
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Armillariella tabescen enzymatic detoxification of aflatoxin B1. Part III. Immobilized enzymatic detoxification. Ann N Y Acad Sci 1998; 864:592-9. [PMID: 9928145 DOI: 10.1111/j.1749-6632.1998.tb10387.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Detoxification of aflatoxin B1 (AFB1) by Armillariella tabescens multienzyme, which was isolated from mycelium pellets of A. tabescens, was confirmed by thin-layer chromatography (TLC) and rat assay. The results of toxicology and pathology studies showed that toxicity of AFB1 was minimized after treatment with A. tabescens multienzyme. The result of the Ames test indicated that the mutagenic activity of multienzyme-treated AFB1 was greatly reduced (or inactivated) compared with that of untreated controls. TLC determinations showed that AFB1 at an initial concentration of 16 microM was completely detoxified (100%) by the fungal multienzyme. The infrared spectrum suggests that the multienzyme is responsible for opening the difuran ring of AFB1.
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87
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Changes in spectral shape of tissue optical properties in conjunction with laser-induced thermotherapy. APPLIED OPTICS 1998; 37:1256-67. [PMID: 18268713 DOI: 10.1364/ao.37.001256] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We measured the optical properties on samples of rat liver tissue before and after laser-induced thermotherapy performed in vivo with Nd:YAG laser irradiation. This made it possible to monitor not only the influence of coagulation on the scattering properties but also the influence of damages to vessels and heat-induced damage to blood on the absorption properties. An experimental integrating-sphere arrangement was modified to allow the determination of the g factor and the absorption and scattering coefficients versus the wavelength in the 600-1050-nm spectral region, with the use of a spectrometer and a CCD camera. The results show a relative decrease in the g factor of on average 21 ? 7% over the entire spectral range following thermotherapy, and a corresponding relative increase in the scattering and absorption coefficients of 23 ? 8% and 200 ? 100%, respectively. An increase of on average 200 ? 80% was consequently found for the reduced scattering coefficient. The cause of these changes in terms of the Mie-equivalent average radius of tissue scatterers as well as of the distribution and biochemistry of tissue absorbers was analyzed, utilizing the information yielded by the g factor and the spectral shapes of the reduced scattering and absorption coefficients. These results were correlated with the alterations in the ultrastructure found in the histological evaluation. The average radius of tissue scattering centers, determined by using either the g factors calculated on the basis of Mie theory or the spectral shape of reduced scattering coefficients calculated on the Mie theory, was estimated to be 21-32% lower in treated than in untreated liver samples. The Mie-equivalent average radii of scattering centers in untreated liver tissue deduced by the two methods corresponded well and were found to be 0.31 and 0.29 mum, respectively, yielding particle sizes in the same range as the size of a mitochondrion.
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Hepatic inflow occlusion increases the efficacy of interstitial laser-induced thermotherapy in rat. J Surg Res 1997; 71:67-72. [PMID: 9271280 DOI: 10.1006/jsre.1997.5121] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Interstitial laser-induced thermotherapy (ILT) destroys tumors thermally. ILT was performed for treatment of liver tumors in rats to investigate the effect of hepatic inflow occlusion on temperature distribution and lesion size. Tumors were irradiated for 20 min with near-infrared light from a neodymium:yttrium-aluminum-garnet (Nd:YAG) laser. The laser light at a power of 1.5 W was delivered through a plane-cut optical fiber, the tip of which was placed in the tumor. Rats in group I received ILT without interruption of hepatic blood flow. Those in group II received ILT during hepatic inflow occlusion. Liver temperatures were measured during treatment. After 3 days the animals were sacrificed and the size of the lesions was measured. Occlusion of the hepatic inflow during ILT increased the maximum lesion diameter, as measured at the liver surface, by 47%. Linear interpolation between the temperatures measured at 6 and 12 mm distance from the fiber tip revealed that the temperature at the necrotic border just before the end of treatment was approximately 45 degrees C in both the occluded and nonoccluded groups, indicating that the hepatic inflow occlusion caused no increase in tissue thermal sensitivity. This study shows that occlusion of the hepatic inflow during interstitial laser-induced thermotherapy causes a significant increase in lesion size, which could have implications for the treatment of hepatic tumors.
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[Epidemiological analysis on the rising of brucellosis prevalence in the area already under controlled]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 1997; 18:15-7. [PMID: 9812474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
An epidemiological analysis was made on the outbreak of brucellosis in Sui-de County, Shaanxi Province in 1995-1996. Result showed that it was one of the most serious brucellosis outbreaks since 1986 when national brucellosis under controlled critiria had been met in the province, and the number of cases was continuously spreading and growing. The incidence was up to 84.8 per 10(5) and the prevalence rate reached 17.5 percent. Patients had typical symptoms with bad conditions. Most all the cases were those who had vocations such as shepherds, etc. Patients' antibody titers were very high with the highest one approached 1:25,600. Two strains of B. melitensis, type III were isolated from the blood of patients.
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Harmonic amplitude distribution in a wideband ultrasonic wavefront after propagation through human abdominal wall and breast specimens. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 1997; 101:1172-1183. [PMID: 9035403 DOI: 10.1121/1.418025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The amplitude characteristics of ultrasonic wavefront distortion produced by transmission through the abdominal wall and breast is described. Ultrasonic pulses were recorded in a two-dimensional aperture after transmission through specimens of abdominal wall or breast. After the pulse arrival times were corrected for geometric path differences, the pulses were temporally Fourier transformed and two-dimensional maps of harmonic amplitudes in the measurement aperture were computed. The results indicate that, as the temporal frequency increases, the fluctuation in harmonic amplitudes increases but the spatial scale of the fluctuation decreases. The normalized second-order and third-order moments of the amplitude distribution also increase with temporal frequency. The wide range variation of these distribution characteristics could not be covered by the Rayleigh, Rician, or K-distribution because of their limited flexibility. However, the Weibull distribution and especially the generalized K-distribution provide better fits to the data. In the fit of the generalized K-distribution, a decrease of its parameter alpha with increasing temporal frequency was observed, as predicted by analysis based on a phase screen model.
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Pharmacokinetic studies on 5-aminolevulinic acid-induced protoporphyrin IX accumulation in tumours and normal tissues. Cancer Lett 1997; 112:225-31. [PMID: 9066732 DOI: 10.1016/s0304-3835(96)04576-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Laser-induced fluorescence (LIF) for in vivo point monitoring and fluorescence microscopy incorporating a CCD camera were used to study the fluorescence distribution of 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) in tumours. Fluorescence in a chemically-induced adenocarcinoma in the liver of rats and in an aggressive basal cell carcinoma in a patient were studied after intravenous injection of ALA at a dose of 30 mg/kg body weight. The LIF technique demonstrated slightly more ALA-induced PpIX fluorescence in the tumour than in the surrounding normal liver and abdominal muscle of rats. The visible parts of the human basal cell carcinoma exhibited strong ALA-induced fluorescence, while this fluorescence was much weaker in the necrotic areas of the tumour and in the surrounding normal skin.
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Tumour vessel damage resulting from laser-induced hyperthermia alone and in combination with photodynamic therapy. Cancer Lett 1997; 111:157-65. [PMID: 9022141 DOI: 10.1016/s0304-3835(96)04528-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This study examined tumour vessel injury resulting from laser-induced hyperthermia alone and in combination with photodynamic therapy (PDT) in the treatment of rat liver tumours by means of scanning electron microscopy. A total of 18 Wistar rats were divided into three groups. Group I (six animals) underwent hyperthermia for 15 min (15-min hyperthermia). Group II (six animals) underwent hyperthermia for 30 min (30-min hyperthermia). Group III (six animals) received the combined treatment of PDT and 30-min hyperthermia. For PDT, delta-amino laevulinic acid at a dose of 60 mg/kg of body weight was intravenously administered 60 min before irradiation at 635 nm. The morphological results indicated that 15-min hyperthermia gave rise to an increase in permeability of the vessels in the treated tumour. Thirty-min hyperthermia caused extreme oedema of vascular endothelial cells and restrictive openings of tumour branch vessels. The combined therapy of PDT and hyperthermia destroyed tumour vasculature. Large breaks of the inner wall of the treated tumour vessels were deeply involved in the basement membrane of the vessel. The results indicate that there may be a close link between inhibition of tumour growth and degree of damage to tumour vessels.
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93
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Propagation and backpropagation for ultrasonic wavefront design. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 1997; 44:1-13. [PMID: 18244096 DOI: 10.1109/58.585184] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Wave backpropagation is a concept that can be used to calculate the excitation signals for an array with programmable transmit waveforms to produce a specified field that has no significant evanescent wave components. This concept can also be used to find the field at a distance away from an aperture based on measurements made in the aperture. For a uniform medium, three methods exist for the calculation of wave propagation and backpropagation: the diffraction integral method, the angular spectrum method, and the shift-and-add method. The boundary conditions that are usually implicitly assumed by these methods are analyzed, and the relationship between these methods are explored. The application of the angular spectrum method to other kinds of boundary conditions is discussed, as is the relationship between wave backpropagation, phase conjugation, and the time-reversal mirror. Wave backpropagation is used, as an example, to calculate the excitation signals for a ring transducer to produce a specified pulsatile plane wave with a limited spatial extent.
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94
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Incorporating diurnal light variation and canopy light attenuation into analytical equations for calculating daily gross photosynthesis. Ecol Modell 1996. [DOI: 10.1016/0304-3800(95)00223-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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95
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Photodynamic therapy using intravenous delta-aminolaevulinic acid-induced protoporphyrin IX sensitisation in experimental hepatic tumours in rats. Br J Cancer 1996; 74:1526-33. [PMID: 8932330 PMCID: PMC2074833 DOI: 10.1038/bjc.1996.584] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The efficacy of photodynamic therapy (PDT) using delta-aminolaevulinic acid (ALA)-induced protoporphyrin IX (PpIX) sensitisation and laser light at 635 nm was investigated in the treatment of experimental hepatic tumours. The model of liver tumours was induced either by local inoculation or by administration of tumour cells through the portal vein in rats. ALA at a dose of 60 mg kg(-1) b.w. was intravenously administered 60 min before PDT. PpIX accumulation in tumour, normal liver and abdominal wall muscle was detected by means of laser-induced fluorescence (LIF). Laser Doppler imaging (LDI) was used to determine changes in the superficial blood flow in connection with PDT. Histopathological examinations were performed to evaluate the PDT effects on the tumour and the surrounding liver tissue, including pathological features in the microvascular system. The accumulation of PpIX, as monitored by LIF, showed high fluorescence intensities at about 635 nm in both the hepatic tumour tissue and normal liver and low values in the abdominal wall. LDI demonstrated that the blood flow in the treated tumour and its surrounding normal liver tissue decreased immediately after the PDT, indicating an effect on the vascular system. A large number of thrombi in the irradiated tumour were found microscopically 3 h after the PDT. The tumour growth rate showed a marked decrease when evaluated 3 and 6 days after the treatment. These results show that the ALA-PDT is effective in the inhibition of growth of experimental hepatic tumours.
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Repeated immunotherapy using intratumoural injection with recombinant interleukin-2 and tumour-infiltrating lymphocytes inhibits growth of breast cancer and induces apoptosis of tumour cells. Cancer Lett 1996; 103:131-6. [PMID: 8635148 DOI: 10.1016/0304-3835(96)04195-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This study tested the effect of repeated intratumoural injection with recombinant interleukin-2 (rIL-2) and tumour-infiltrating lymphocytes (TILs) on inhibition of growth of breast cancer and on induction of apoptosis of tumour cells. The tumour cell line LDLX43 was used to induce breast cancer in Wistar rats. Group I (10 rats) was the control. Group II (12 rats) received repeated intratumoural injection with rIL-2 and TILs. rIL-2 at the dose of 5 x 10(5) IU/day was given for 7 days, and 1 x 10(7) TILs were injected on the second day of each rIL-2 therapy, for a treatment session. Overall, two treatment sessions of immunotherapy with rIL-2 and TILs were given in all treated animals. Rapid increased tumour volume was found in the control group. In the treated group the total response rate was 42%, of which 25% tumours showed partial regression and 17% tumours reached complete remission where infiltration of plenty of T lymphocytes was detected, indicating that T cell-mediated antitumour immunity is primarily responsible for tumour rejection. Further investigation showed the repeated immunotherapy using intratumoural injection with rIL-2 and TILs could induce the development of apoptosis of breast cancer cells.
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Multiple-system organ damage resulting from prolonged hepatic inflow interruption. ARCHIVES OF SURGERY (CHICAGO, ILL. : 1960) 1996; 131:442-7. [PMID: 8615734 DOI: 10.1001/archsurg.1996.01430160100022] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND It has been reported that patients undergoing major hepatectomy tolerated 90 and 127 minutes of continuous hepatic inflow interruption with no evidence of permanent damage to the liver. We questioned the safety and feasibility of the interruption beyond 90 minutes in normothermic human beings. We also postulated that, besides injury to the liver per se, extended continuous hepatic inflow interruption would cause extrahepatic multiple-system organ damage in subjects exposed to continuous hepatic inflow interruption for 90 or 120 minutes. DESIGN Fifty Sprague-Dawley rats were divided into three groups. Group 1 served as controls that had only laparotomy. Group 2 underwent continuous hepatic inflow interruption for 90 minutes, and group 3 was subjected to continuous hepatic inflow interruption for 120 minutes. Scanning electron microscopy and transmission electron microscopy were used to evaluate ultrastructural alterations in the liver, lung, heart, and intestine. SETTING Lund (Sweden) University Hospital and Top Cancer Institute, Lund. INTERVENTIONS Intraoperative and postoperative infusion and blood transfusion were given in all experimental animals. MAIN OUTCOME MEASURES Animal survival and manifestations of multiple-system organ failure. RESULTS In rats with continuous hepatic inflow interruption for 90 or 120 minutes, scanning electron microscopy showed a necrotic surface of the liver cells together with fibrin exudation. Hepatic sinusoids and intrahepatic nerves also had severe injury. Destruction of pulmonary structures and breakdown of microcirculation in the lung were characterized by thinned and ruptured walls of alveoli and a greatly decreased number of capillaries in the damaged alveolar wall. Transmission electron microscopy showed four types of ultrastructural changes, ie, necrosis of epithelial cells, extremely swollen mitochondria in intestinal cells, death of mucosal cells, and increased permeability of vessels in the injured intestine. The affected heart manifested highly enlarged mitochondria in myocardial cells, thickened vascular walls, and scattered necrotic lesions in myocardial tissue. CONCLUSIONS Multiple-system organ failure resulting from ischemia-reperfusion injury and obstacle of portal hemodynamics in a subject subjected to an extended continuous hepatic inflow interruption is an unrecognized new disorder that may cause a high mortality rate. Our preliminary results indicated that animals subjected to continuous hepatic inflow interruption for 90 or 120 minutes developed various injuries to the liver, lung, heart, and gut. Therefore, we believe that continuous hepatic inflow interruption exceeding 90 minutes could also be hazardous in human beings.
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Two isozymes of P450nor of Cylindrocarpon tonkinense: molecular cloning of the cDNAs and genes, expressions in the yeast, and the putative NAD(P)H-binding site. Biochimie 1996; 78:792-9. [PMID: 9010609 DOI: 10.1016/s0300-9084(97)82538-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The cDNAs and genes for two isozymes of cytochrome P450nor of the fungus Cylindrocarpon tonkinense, P450nor1 and P450nor2, were cloned and sequenced. Their deduced amino acid sequences respectively showed 83 and 70% identity to that of P450nor of Fusarium oxysporum, and 69% identity to each other. The genes for P450nor1 and P450nor2 were termed, respectively, CYP 55A2 and CYP 55A3. The cDNA for P450nor1 contained a targeting-like presequence upstream the N-terminus of mature protein whereas that for P450nor2 did not, suggesting their different intracellular localisations. We also succeeded in expressing these P450nor isoforms in the host-vector system of the yeast Saccharomyces cerevisiae. We purified one of the recombinant proteins, P450nor of F oxysporum. Little difference could be observed between the native and recombinant proteins in catalytic and spectroscopic properties. We constructed chimeric proteins of P450nor of F oxysporum and P450nor2 which are different in their specificity against the electron donors: reduced pyridine nucleotides. The specificity of chimeric proteins against NADH/NADPH showed that the specificity is determined by the N-terminal half of protein. We found a consensus amino acid sequence between three isoforms of P450nor, A-X-G-X-X-A, similar to the NAD-binding motif G-X-G-X-X-G/A in the region that corresponds to the B'-helix in P450cam.
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Abstract
BACKGROUND Anatomic knowledge of vasculature of the splenic lobe and segment is of great clinical significance in partial resections and transplantation of the spleen. METHODS The methods of two-colored corrosion casting, roentgenography, and anatomic dissection were used to evaluate the vasculature of the splenic hilum and intraspleen. On this basis splenic lobectomy and segmentectomy were performed on 42 patients with traumatized spleens. RESULTS In the observation of 850 spleen specimens the spleen showed a single lobar artery in 7 cases (0.8%), two lobar arteries in 730 cases (86%), three lobar arteries in 104 cases (12.2%), and multiple lobar arteries (i.e., more than three lobar arteries) in 9 cases (1%). In a subgroup of 276 specimens 17%, 53%, 24%, 4%, 1%, and 1% of spleen specimens had three, four, five, six, seven, and eight segmental arteries, respectively. The result from a subgroup of 280 specimens indicated that mean percentages of the existence of the superior and inferior polar arteries and of the coexistence of both polar arteries were 31.3%, 38.8%, and 13.3%, respectively. Relative avascular planes between segments or lobes were seen. Basic steps of splenic lobectomy or segmentectomy include mobilization of the injured spleen, ligation of vessels in the lobe or segment, transection of the splenic parenchyma, and sutures of the cut surface of the remaining spleen. The postoperative courses of all 42 patients undergoing partial splenectomy were uneventful. No postoperative bleeding and necrosis of the remaining spleen or infectious complications were registered. CONCLUSIONS Anatomically the spleen is defined with two primary lobes (the superior lobe and inferior lobe), one accessory lobe, and three to five segments. This new classification facilitates surgeons to perform partial resections of the spleen and allotransplantation of the hemispleen from a living related donor in human beings.
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[Several methods beneficial to the memory of students in studying basic nursing]. ZHONGHUA HU LI ZA ZHI = CHINESE JOURNAL OF NURSING 1995; 30:729-30. [PMID: 8716656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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