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991.
992.
Camilla Dickson 《Vegetation History and Archaeobotany》1996,5(1-2):25-31
Plant remains from the 15th century drains at Paisley Abbey, Scotland include medicinal plants which may have grown in the
abbey's physic garden. They are Chelidonium majus, Conium maculatum, Euphorbia lathyris, and Papaver somniferum. Plants with both medicinal and culinary uses are Rumex pseudoalpinus and cf Armoracia rusticana. Other vegetables are represented by Allium sp. and Brassica spp. Malus domestica and Prunus domestica ssp. insititia would have been grown in the abbey's orchard. Juglans regia, represented by nut and wood fragments, was either grown in the orchard or imported. Ficus carica was certainly imported as dried fruit from the Mediterranean region. Myristica fragrans as mace came from Indonesia. Locally grown plants are Avena strigosa, Hordeum, Triticum/Secale, Linum usitatissimum and the dye plant Reseda luteola. It is known that spices and other foodstuffs were purchased at fairs at Berry, Bruges and Antwerp and imported into Scotland
at the end of the 15th century. 相似文献
993.
Rosfjord EC Maemura M Johnson MD Torri JA Akiyama SK Woods VL Dickson RB 《Experimental cell research》1999,248(1):260-271
Cellular adhesions to other cells and to the extracellular matrix play crucial roles in the malignant progression of cancer. In this study, we investigated the role of protein kinase C (PKC) in the regulation of cell-substratum adhesion by the breast adenocarcinoma cell line MCF-7. A PKC activator, 12-O-tetradecanoylphorbol-l, 3-acetate (TPA), stimulated cell adhesion to laminin and collagen I in a dose-dependent manner over a 1- to 4-h interval. This enhanced adhesion was mediated by alpha2beta1 integrin, since both anti-alpha2 and anti-beta1 blocking antibodies each completely abrogated the TPA-induced adhesion. FACS analysis determined that TPA treatment does not change the cell surface expression of alpha2beta1 integrin over a 4-h time interval. However, alpha2beta1 levels were increased after 24 h of TPA treatment. Thus, the enhanced avidity of alpha2beta1-dependent cellular adhesion preceded the induction of alpha2beta1 cell surface expression. Northern blot analysis revealed that mRNA levels of both alpha2 and beta1 subunits were increased after exposure to TPA for 4 h, indicating that the induction of alpha2beta1 mRNA preceded that of its cell surface expression. This further suggested that the TPA-induced avidity of alpha2beta1 was independent of increased expression of alpha2beta1. Pretreatment of cells with the PKC inhibitor calphostin C partially antagonized the TPA-induced increase in expression of alpha2beta1 integrin expression and of alpha2beta1-mediated cellular adhesion. To identify a possible mechanism by which TPA could be acting to promote the rapid induction of alpha2beta1 adhesion, we treated the cells with the Rho-GTPase inhibitor Clostridium botulinumexotoxin C3. C3 inhibited TPA-induced adhesion to laminin and collagen I in a dose-dependant manner, suggesting a likely role for Rho in TPA-induced adhesion. Together, these results suggest that PKC can modulate the alpha2beta1-dependent adhesion of MCF-7 cells by two distinct mechanisms: altering the gene expression of integrins alpha2 and beta1 and altering the avidity of the alpha2beta1 integrin by a Rho-dependant mechanism. 相似文献
994.
Sahara N Lewis J DeTure M McGowan E Dickson DW Hutton M Yen SH 《Journal of neurochemistry》2002,83(6):1498-1508
Transgenic mice (JNPL3), which develop neurofibrillary degeneration and express four-repeat human tau with P301L missense mutation, were characterized biochemically to determine whether the development of aggregated tau from soluble tau involves an intermediate stage. Homogenates from mice of different ages were separated into buffer-soluble (S1), sarkosyl- and salt-extractable (S2) and sarkosyl-insoluble pellet (P3) fractions, and analyzed for human tau distribution, phosphorylation and filament formation. S1 and S2 fractions contained 50-60-kDa tau whereas the S2 fraction also had 64-kDa tau. The level of tau in the P3 fraction increased in an age-dependent manner and correlated positively with the soluble tau concentration. The P3 fraction from 2.5-6.5-month-old mice contained 64- and 50-60-kDa tau, whereas that from 8.5-month and older transgenic animals contained mostly 64-kDa and higher molecular weight tau. The S2 and P3 fractions contained comparable amounts of 64-kDa tau. The 64-kDa tau was predominantly human, and phosphorylated at multiple sites: Thr181, Ser202/Thr205, Thr212, Thr231, Ser262, Ser396/Ser404, Ser409 and Ser422. Most of these sites were phosphorylated to a lesser extent in S2 than in P3 fractions. Tau polymers were detected in P3 fractions from 3-month and older female JNPL3 mice, but not in non-transgenic controls. The results suggest that tau in S2 represents an intermediate from which insoluble tau is derived, and that phosphorylation may play a role in filament formation and/or stabilization. 相似文献
995.
Brandon Le Naomi Clarke Sze Fui Hii Aisling Byrne Patsy A. Zendejas-Heredia Susanna Lake Oliver Sokana Alam Khattak Lucia Romani Daniel Engelman Titus Nasi Dickson Boara John Kaldor Andrew Steer Rebecca Traub Susana Vaz Nery 《PLoS neglected tropical diseases》2022,16(5)
BackgroundThe Kato-Katz microscopy technique is the global standard for assessment of soil-transmitted helminth (STH) burden. However, major limitations include its poor sensitivity, requirement for rapid sample processing, and inability to differentiate hookworm species nor detect Strongyloides spp. infections. We assessed the prevalence and intensity of STH species in Solomon Islands by conducting a province-wide survey using quantitative PCR (qPCR) for diagnosis, which can provide much better characterisation of STH burden than microscopy.Methodology/Principal findingsWe conducted a cross-sectional survey in 18 villages in Western Province to detect infections with six STH species and quantify intensity with three. We used linear mixed model regression to identify potential water, sanitation, and hygiene (WASH) and environmental risk factors for infection. We collected stool specimens from 830 village residents. Overall STH prevalence was 63.3% (range 27.5 to 91.5% across villages), led by Necator americanus (54.5% [range 17.5–89.4%]), followed by Ancylostoma ceylanicum (15.5% [range 2.8–45.8%]), Trichuris trichiura (9.1% [range 0–79.2%]), and Strongyloides spp. (3.2% [range 0–29.2%]). Most infections were of light intensity for N. americanus (85.7%) and T. trichiura (90.7%). Owning a household latrine was associated with a lower risk of N. americanus infection (AOR 0.41, 95% CI 0.24–0.68) while greater precipitation was linked to more common T. trichiura infection (AOR 1.14, 95% CI 1.04–1.25).Conclusion/SignificanceIn this first large-scale population survey of STH in the Pacific using qPCR, we found evidence that ivermectin should be incorporated into STH control programmes because of the presence of T. trichiura and Strongyloides spp., both of which are poorly responsive to albendazole. Furthermore, One Health strategies are needed for improved A. ceylanicum and Strongyloides spp. control, WASH access and use should be improved to complement deworming programmes, and control efforts should ideally be expanded to entire communities.Trial registrationClinicalTrials.gov Australian and New Zealand Clinical Trials Registry ACTRN12618001086257. 相似文献
996.
Autocrine and paracrine growth regulation of human breast cancer 总被引:4,自引:0,他引:4
M E Lippman R B Dickson A Kasid E Gelmann N Davidson M McManaway K Huff D Bronzert S Bates S Swain 《Journal of steroid biochemistry》1986,24(1):147-154
Previous work from our laboratory has demonstrated that human breast cancer (BC) cells in culture can be stimulated by physiologic concentrations of estrogen. In an effort to further understand this process, we have examined the biochemical and biological properties of proteins secreted by human BC cells in vitro. We have developed a defined medium system which simultaneously allows the collection of factors secreted by the BC cells, facilitates their purification and allows for an unequivocal assay of their effect on other BC cells. By both biochemical and radioimmunoassay procedures, MCF-7 cells secrete large quantities of IGF-I-like activity. The cells contain receptors for IGF-I and are stimulated by physiologic concentrations of IGF-I. Multiple additional peaks of growth stimulatory activity can be obtained by partial purification of conditioned media from human BC cells by sequential dialysis, acid extraction and Biogel P60 chromatography. These peaks are induced up to 200-fold by physiologic concentrations of estrogen. Several of these peaks cross-react in a radioreceptor assay with EGF and are thus candidates for transforming growth factors. Monoclonal antibodies (MCA) have been prepared which react with secreted proteins from the MCF-7 cells. One of these MCAs binds to material from MCF-7 and ZR-75-1 hormone-dependent BC cells only when these two lines are treated with estrogen but reacts with conditioned medium from several other hormone-independent cell lines in the absence of estrogen stimulation. This MCA is currently undergoing further characterization and evaluation of its biological potency. We conclude that with estrogen stimulation, hormone-dependent human BC cells secrete peptides which when partially purified can replace estrogen as a mitogen. Their role as autocrine or paracrine growth factors and their effects on surrounding nonneoplastic stroma may suggest a means of interfering with tumor proliferation. 相似文献
997.
998.
Visualisation of mycorrhizal fungal structures and quantification of their surface area and volume using laser scanning confocal microscopy 总被引:5,自引:0,他引:5
A method has been developed for the visualisation and three-dimensional (3D) measurement of mycorrhizal fungal structures
inside plant roots. Sections of Allium porrum L. roots colonised by Glomus sp. 'City Beach' (WUM 16) and Lilium sp. roots colonised by Scutellospora calospora (Nicol. & Gerd.) Walker & Sanders (WUM 12(2)) were stained with acid fuchsin. This allowed fluorescence from the fungal structures
to be observed under a laser scanning confocal microscope (LSCM) without interference from the plant cells. A series of horizontal
optical sections were collected from a Glomus sp. arbuscule and from a hyphal coil of S. calospora. These data were used to produce extended focus images. Axial distortion in microscopic visualisation due to the refractive
index mismatch between the immersion and mounting media was quantified using vertical scanning of the hyphae. A correction
factor of 0.71 μm was used for the z-interval between the xy-slices. A series of binary xy-images from each structure was
rendered into a 3D graphical model for viewing. The volume and surface area of the structures were estimated using computerised
3D measurement and also by stereological integration of binary xy-images. With both structures, the surface area estimates
varied greatly between the two measuring systems, whereas differences in volume estimates were small. Computerised 3D measurement
was considered more accurate than stereological integration of confocal binary images.
Accepted: 25 August 1999 相似文献
999.
Pasteuria penetrans has .been identified as an important biological control agent of root-knot nematodes. In this study the use of tally thresholds was evaluated for estimating P. penetrans endospore attachment to second-stage juveniles (J2) of Meloidogyne spp. A tally threshold (T) is defined as the maximum number of individuals in a sample unit that may be treated as absent based on binomial sampling. Three different data sets that originated from centrifugal bioassay, incubation bioassay, and field experiments were investigated. The data sets each contained 70, 33, and 111 estimates of the mean number of endospores attached per J2 (m), respectively. Empirical relationships between m and proportions of J2 with ≤T endospores attached (PT) were developed using parameters from the linear regression of ln(m) on PT (0 < PT < 1): ln(m) = a + b PT, T was set to 0, 1, 2, 3, 4, 5, 8, and 10 endospores/J2. The results indicated that the variances of linear equations tended to decrease with increasing T values for all three data sets. T values of 0, 1, 8, and 10 endospores/J2 for centrifugal bioassay and incubation bioassay, and of 0, 1, 2, and 3 endospores/J2 for field experiments were associated with an r² of >= 0.8. These T values were robust for estimating m from PT, reducing the variability as well as the time and effort spent in estimating the mean number of endospores attached per J2. 相似文献
1000.
M E Lippman R B Dickson E P Gelmann N Rosen C Knabbe S Bates D Bronzert K Huff A Kasid 《Journal of steroid biochemistry》1988,30(1-6):53-61
The mechanisms by which human breast cancers regulate their own growth have been studied by us in an in vitro model system. We showed that specific growth factors (IGF-I, TGF alpha, PDGF) are secreted by human breast cancer cells. A variety of experiments suggest that they are involved in tumor growth and progression. These activities are induced by estradiol in hormone-dependent breast cancer cells and secreted constitutively by estrogen-independent cells. Concentrates of conditioned medium derived from breast cancer cells can induce the growth of hormone-dependent cells in vivo in athymic nude mice. Hormone-dependent breast cancer cells also secrete TGF beta. TGF beta is growth inhibitory. Growth inhibitors such as antiestrogens or glucocorticoids increase TGF beta secretion. An antiestrogen-resistant mutant of MCF-7 cells does not secrete TGF beta when treated with antiestrogen, but is growth inhibited when treated with exogenous TGF beta. Thus, TGF beta functions as a negative autocrine growth regulator and is probably responsible for some of the growth inhibitory effects of antiestrogens. 相似文献