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81.
Armin Keuper Klaus Kalmring Andrea Schatral William Latimer Werner Kaiser 《Oecologia》1986,70(3):414-422
Summary The acoustic behaviour of the closely related tetigoniid species Psorodonotus illyricus and Decticus verrucivorus have been invectigated by bioacoustical and behavioural methods. Both species show adaptations concerning the acoustic behaviour with respect to the biotope and the properties of sound propagation. These insects inhabit low grassland with an average vegetation height of about 20 cm which is also the general height for the song perches. Difficulties arise for efficient acoustic communication in such habitats. Sound propagation is influenced and limited by the strong ground attenuation and the excess damping by grass vegetation. Other limiting factors are the microclimatic conditions in the biotope. The two species counteract these difficulties by moving around in the biotope during stridulation. Both species mainly stridulate in the morning, avoiding problems of reduced sound transmission which often appear in the afternoon due to negative temperature gradients and resulting shadow zones. From the high mobility of these insects, it follows that individuals have no fixed territory and consequently no rivalry against conspecifics, which is very common among Orthopterans with a high degree of territoriality. It can be concluded that the preferred biotope influences and creates behavioural patterns in Orthopterans, especially here in the two investigated species of bushcrickets Psorodonotus illyricus and Decticus verrucivorus. 相似文献
82.
Tissue- and species-specific regulation of murine alpha 1-antitrypsin gene transcription 总被引:2,自引:0,他引:2
C Rheaume J J Latimer H Baumann F G Berger 《The Journal of biological chemistry》1988,263(29):15118-15121
83.
Dentifrices can augment oral hygiene by inactivating bacteria and at sub-lethal concentrations may affect bacterial metabolism, potentially inhibiting acidogenesis, the main cause of caries. Reported herein is the development of a rapid method to simultaneously measure group-specific bactericidal and acidogenesis-mitigation effects of dentifrices on oral bacteria. Saliva was incubated aerobically and anaerobically in Tryptone Soya Broth, Wilkins-Chalgren Broth with mucin, or artificial saliva and was exposed to dentifrices containing triclosan/copolymer (TD); sodium fluoride (FD); stannous fluoride and zinc lactate (SFD1); or stannous fluoride, zinc lactate and stannous chloride (SFD2). Minimum inhibitory concentrations (MIC) were determined turbidometrically whilst group-specific minimum bactericidal concentrations (MBC) were assessed using growth media and conditions selective for total aerobes, total anaerobes, streptococci and Gram-negative anaerobes. Minimum acid neutralization concentration (MNC) was defined as the lowest concentration of dentifrice at which acidification was inhibited. Differences between MIC and MNC were calculated and normalized with respect to MIC to derive the combined inhibitory and neutralizing capacity (CINC), a cumulative measure of acidogenesis-mitigation and growth inhibition. The overall rank order for growth inhibition potency (MIC) under aerobic and anaerobic conditions was: TD> SFD2> SFD1> FD. Acidogenesis-mitigation (MNC) was ordered; TD> FD> SFD2> SFD1. CINC was ordered TD> FD> SFD2> SFD1 aerobically and TD> FD> SFD1> SFD2 anaerobically. With respect to group-specific bactericidal activity, TD generally exhibited the greatest potency, particularly against total aerobes, total anaerobes and streptococci. This approach enables the rapid simultaneous evaluation of acidity mitigation, growth inhibition and specific antimicrobial activity by dentifrices. 相似文献
84.
Light scattering vs. microscopy for measuring average cell size and shape. 总被引:3,自引:0,他引:3
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P Latimer 《Biophysical journal》1979,27(1):117-126
Light-scattering photometry is compared with electron and light microscopy as a source of information about the average size and shape of cells in population. Examined are the effects of limited instrument resolution, necessary experimental procedures, and cell heterogeneity. Information theory is used to survey the relative amounts of information provided by photometric and microscopic measurements. Then in model exploratory experiments, cell size and shape and changes therein are determined both by microscopy and by photometry for spherical and spheroidal cells. Scattering theory is used to calculate photometrically observed light from cell parameters. It is found that if certain other appropriate information about the morphological property of interest is available, then visible light photometry is the preferred method for obtaining quantitative information. It has good absolute sensitivity (0.01-0.10 micrometers resolution), its results are relatively unaffected by sample heterogeneity, it is nondestructive and compatible with many other techniques, it requires no sample preparation, and it provides its information in real time. 相似文献
85.
86.
Thomas Fleischer Arnoldo Frigessi Kevin C Johnson Hege Edvardsen Nizar Touleimat Jovana Klajic Margit LH Riis Vilde D Haakensen Fredrik W?rnberg Bj?rn Naume ?slaug Helland Anne-Lise B?rresen-Dale J?rg Tost Brock C Christensen Vessela N Kristensen 《Genome biology》2014,15(8)
Background
Ductal carcinoma in situ (DCIS) of the breast is a precursor of invasive breast carcinoma. DNA methylation alterations are thought to be an early event in progression of cancer, and may prove valuable as a tool in clinical decision making and for understanding neoplastic development.Results
We generate genome-wide DNA methylation profiles of 285 breast tissue samples representing progression of cancer, and validate methylation changes between normal and DCIS in an independent dataset of 15 normal and 40 DCIS samples. We also validate a prognostic signature on 583 breast cancer samples from The Cancer Genome Atlas. Our analysis reveals that DNA methylation profiles of DCIS are radically altered compared to normal breast tissue, involving more than 5,000 genes. Changes between DCIS and invasive breast carcinoma involve around 1,000 genes. In tumors, DNA methylation is associated with gene expression of almost 3,000 genes, including both negative and positive correlations. A prognostic signature based on methylation level of 18 CpGs is associated with survival of breast cancer patients with invasive tumors, as well as with survival of patients with DCIS and mixed lesions of DCIS and invasive breast carcinoma.Conclusions
This work demonstrates that changes in the epigenome occur early in the neoplastic progression, provides evidence for the possible utilization of DNA methylation-based markers of progression in the clinic, and highlights the importance of epigenetic changes in carcinogenesis.Electronic supplementary material
The online version of this article (doi:10.1186/s13059-014-0435-x) contains supplementary material, which is available to authorized users. 相似文献87.
C.J. Hernandez D.A. Loomis A.L. Schifle L. Elsmore B. Latimer 《Journal of human evolution》2009,56(5):462-470
Considerable differences in spinal morphology have been noted between humans and other hominoids. Although comparative analyses of the external morphology of vertebrae have been performed, much less is known regarding variations in internal morphology (density) and biomechanical performance among humans and closely related non-human primates. In the current study we utilize density calibrated computed tomography images of thoracic vertebral bodies from hominoids (n = 8-15 per species, human specimens 20-40 years of age) to obtain estimates of vertebral bone strength in axial compression and anteroposterior bending and to determine how estimates of strength scale with animal body mass. Our biomechanical analysis suggests that the strength of thoracic vertebral bodies is related to body mass (M) through power law relationships (y ∝ Mb) in which the exponent b is 0.89 (reduced major axis) for prediction of axial compressive strength and is equal to 1.89 (reduced major axis) for prediction of bending strength. No differences in the relationship between body mass and strength were observed among hominoids. However, thoracic vertebrae from humans were found to be disproportionately larger in terms of vertebral length (distance between cranial and caudal endplates) and overall vertebral body volume (p < 0.05). Additionally, vertebral bodies from humans were significantly less dense than in other hominoids (p < 0.05). We suggest that reduced density in human vertebral bodies is a result of a systemic increase in porosity of cancellous bone in humans, while increased vertebral body volume and length are a result of functional adaptation during growth resulting in a vertebral bone structure that is just as strong, relative to body mass, as in other hominoids. 相似文献
88.
Kim D Baas Maarten WJ Koeter Henk C van Weert Peter Lucassen Claudi LH Bockting Karin A Wittkampf Aart H Schene 《Trials》2010,11(1):1-6
Background
Previous studies of acupuncture show favourable results for both subjective and objective outcomes of dry eye. However, firm conclusions could not be drawn from these studies because the quality of the trials was too low to establish concrete evidence. Therefore, this study was designed both to avoid the flaws of the existing trials and to assess the effectiveness, cost-effectiveness and qualitative characteristics of acupuncture treatment for dry eye.Methods/design
One hundred fifty participants with dry eye will be recruited into three independent hospitals from different areas: Korea Institute of Oriental Medicine, DongGuk University Ilsan Oriental Hospital and Dongshin University Gwangju Oriental Hospital. The number of participants required was calculated from the data of a previous, relevant study. These patients will be randomly allocated into acupuncture treatment or artificial tear groups. Either 17 acupuncture points (bilateral BL2, GB14, TE 23, Ex1, ST1, GB20, LI4, LI11 and single GV23) will be used 3 times a week or disposable artificial tear drops (Refresh Plus®, ALLERGAN) will be provided for use at least once a day for 4 weeks. The ocular surface disease index (OSDI), tear film break-up time (TFBUT), Schirmer I test, visual analogue scale (VAS) for self-assessment of ocular discomfort, general assessment (by both acupuncture practitioners and participants) and quality of life (QOL) through the Measure Yourself Medical Outcome Profile-2 (MYMOP-2) will be assessed for approximately 3-months for each study participant. In addition, qualitative study and cost-effectiveness of acupuncture treatment will be conducted.Trial registration
ClinicalTrials.gov (Identifier: NCT01105221). 相似文献89.
Visus C Ito D Dhir R Szczepanski MJ Chang YJ Latimer JJ Grant SG DeLeo AB 《Cancer immunology, immunotherapy : CII》2011,60(7):919-929
Hydroxysteroid (17β) dehydrogenase type 12 (HSD17B12) is a multifunctional isoenzyme functional in the conversion of estrone
to estradiol (E2), and elongation of long-chain fatty acids, in particular the conversion of palmitic to archadonic (AA) acid,
the precursor of sterols and the inflammatory mediator, prostaglandin E2. Its overexpression together with that of COX-2 in breast carcinoma is associated with a poor prognosis. We have identified
the HSD17B12114–122 peptide (IYDKIKTGL) as a naturally presented HLA-A*0201 (HLA-A2)-restricted CD8+ T-cell-defined epitope. The HSD17B12114–122 peptide, however, is poorly immunogenic in its in vitro ability to induce peptide-specific CD8+ T cells. Acting as an “optimized peptide”, a peptide (TYDKIKTGL), which is identical to the HSD17B12114–122 peptide except for threonine at residue 1, was required for inducing in vitro the expansion of CD8+ T-cell effectors cross-reactive against the HSD17B12114–122 peptide. In IFN-γ ELISPOT assays, these effector cells recognize HSD17B12114–122 peptide-pulsed target cells, as well as HLA-A2+ squamous cell carcinoma of the head and neck (SCCHN) and breast carcinoma cell lines overexpressing HSD17B12 and naturally
presenting the epitope. Whereas growth inhibition of a breast carcinoma cell line induced by HSD17B12 knockdown was only reversed
by AA, in a similar manner, the growth inhibition of the SCCHN PCI-13 cell line by HSD17B12 knockdown was reversed by E2 and
AA. Our findings provide the basis for future studies aimed at developing cancer vaccines for targeting HSD17B12, which apparently
can be functional in critical metabolic pathways involved in inflammation and cancer. 相似文献
90.
Yiying Liu Irene de Bruijn Allison LH Jack Keith Drynan Albert H van den Berg Even Thoen Vladimir Sandoval-Sierra Ida Skaar Pieter van West Javier Diéguez-Uribeondo Menno van der Voort Rodrigo Mendes Mark Mazzola Jos M Raaijmakers 《The ISME journal》2014,8(10):2002-2014
Animals and plants are increasingly suffering from diseases caused by fungi and oomycetes. These emerging pathogens are now recognized as a global threat to biodiversity and food security. Among oomycetes, Saprolegnia species cause significant declines in fish and amphibian populations. Fish eggs have an immature adaptive immune system and depend on nonspecific innate defences to ward off pathogens. Here, meta-taxonomic analyses revealed that Atlantic salmon eggs are home to diverse fungal, oomycete and bacterial communities. Although virulent Saprolegnia isolates were found in all salmon egg samples, a low incidence of Saprolegniosis was strongly correlated with a high richness and abundance of specific commensal Actinobacteria, with the genus Frondihabitans (Microbacteriaceae) effectively inhibiting attachment of Saprolegniato salmon eggs. These results highlight that fundamental insights into microbial landscapes of fish eggs may provide new sustainable means to mitigate emerging diseases. 相似文献