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991.
992.
Previous studies have shown that the viral oncogene product, v-Src, is localized to a perinuclear structure. Here, we demonstrate by immunofluorescence analysis that the perinuclear structure corresponds to a local concentration of vesicles. Overexpressed normal cellular Src, c-Src, and a temperature-sensitive mutant of v-Src also are associated with these perinuclear vesicles. This perinuclear localization is observed in a variety of cell types using several different antibodies to Src, and it is independent of the fixation method. Immunoelectron ultracryomicroscopic analysis of rat fibroblast cells transformed by v-Src demonstrates an association of this protein with the limiting membranes of vesicles concentrated in the perinuclear region. These vesicles appear at the electron microscopic level to be multivesicular bodies on the basis of their size (0.3-1.0 microns in diameter), large electron-transparent lumens, and electron-dense vesicular inclusions. Morphometric analysis indicates that approximately 20% of the total cell v-Src protein is associated with these structures. This subpopulation of v-Src may have been recovered from the plasma membrane via the endocytotic pathway in a manner analogous to endocytosis of the epidermal growth factor receptor. Localization of the Src tyrosine kinases to these perinuclear endocytotic vesicles may be necessary for oncogenic transformation by v-Src and for normal functions of c-Src. 相似文献
993.
994.
In-vessel bioreduction provides an effective storage and pre-treatment method for livestock carcasses prior to final disposal 总被引:1,自引:0,他引:1
A. Prysor Williams Gareth Edwards-JonesDavid L. Jones 《Bioresource technology》2009,100(17):4032-4040
The EU Animal By-Products Regulations forbid the burial of livestock carcasses on land. Farmers would benefit from the availability of biosecure and economically viable alternatives for storing and disposing of dead animals. We assessed the efficacy of bioreduction vessels as a mechanism of storing and reducing the volume of fallen livestock prior to ultimate disposal. Two experimental scenarios were tested: (1) a single input of 300 kg of dead sheep with no further inputs for 3 months, and (2) a continuous ‘on-farm’ addition of dead sheep over 12 months (ca. 2–3 t animals vessel−1). The trials involved half-filling the vessels with water, addition of the dead sheep with subsequent heating (40 °C) and aeration of the liquor. Each trial was repeated three times. Our results showed a complete biodigestion and liquefaction of the animals alongside a significant bioreduction in the volume of the liquid. No pathogens could be detected in either the waste or the gaseous emissions. Calculations showed that bioreduction may offer significant long-term savings for farmers in terms of animal disposal costs. Our findings suggest that bioreduction may offer a practical, biosecure, and cost-effective method of storing fallen livestock prior to disposal via rendering or incineration. 相似文献
995.
Min Tan Gareth Jones Guangjian Zhu Jianping Ye Tiyu Hong Shanyi Zhou Shuyi Zhang Libiao Zhang 《PloS one》2009,4(10)
Oral sex is widely used in human foreplay, but rarely documented in other animals. Fellatio has been recorded in bonobos Pan paniscus, but even then functions largely as play behaviour among juvenile males. The short-nosed fruit bat Cynopterus sphinx exhibits resource defence polygyny and one sexually active male often roosts with groups of females in tents made from leaves. Female bats often lick their mate''s penis during dorsoventral copulation. The female lowers her head to lick the shaft or the base of the male''s penis but does not lick the glans penis which has already penetrated the vagina. Males never withdrew their penis when it was licked by the mating partner. A positive relationship exists between the length of time that the female licked the male''s penis during copulation and the duration of copulation. Furthermore, mating pairs spent significantly more time in copulation if the female licked her mate''s penis than if fellatio was absent. Males also show postcopulatory genital grooming after intromission. At present, we do not know why genital licking occurs, and we present four non-mutually exclusive hypotheses that may explain the function of fellatio in C. sphinx. 相似文献
996.
Form and function of fungal spore appendages 总被引:3,自引:0,他引:3
E.B. Gareth Jones 《Mycoscience》2006,47(4):167-183
A wide variety of fungi have spores with appendages or mucilaginous sheaths, which are most elaborate in aquatic ascomycetes,
especially marine species. The form and structure of a wide range of appendaged spores are documented from both taxonomic
and ecological fungal groups, and their role in nature is discussed. The effect of environmental factors on appendage development
and how ascospores are adapted for release from asci are reviewed. How fungi evolved such a variety of appendages in form
and structure is also discussed.
This article is dedicated to the late Professor Keisuke Tubaki for his invaluable contribution to mycology and for all his
encouragement and support to the author over many years. I appreciate the invitation of the Japanese Mycological Society to
write on the above subject, congratulate the society on their 50th anniversary, and wish it well in the coming years. 相似文献
997.
Gareth LuTheryn Peter Glynne-Jones Jeremy S Webb Dario Carugo 《Microbial biotechnology》2020,13(3):613-628
Bacterial biofilms are an ever-growing concern for public health, featuring both inherited genetic resistance and a conferred innate tolerance to traditional antibiotic therapies. Consequently, there is a growing interest in novel methods of drug delivery, in order to increase the efficacy of antimicrobial agents. One such method is the use of acoustically activated microbubbles, which undergo volumetric oscillations and collapse upon exposure to an ultrasound field. This facilitates physical perturbation of the biofilm and provides the means to control drug delivery both temporally and spatially. In line with current literature in this area, this review offers a rounded argument for why ultrasound-responsive agents could be an integral part of advancing wound care. To achieve this, we will outline the development and clinical significance of biofilms in the context of chronic infections. We will then discuss current practices used in combating biofilms in chronic wounds and then critically evaluate the use of acoustically activated gas microbubbles as an emerging treatment modality. Moreover, we will introduce the novel concept of microbubbles carrying biologically active gases that may facilitate biofilm dispersal. 相似文献
998.
Marka R. Crittenden Talicia Savage Benjamin Cottam Keith S. Bahjat William L. Redmond Shelly Bambina Melissa Kasiewicz Pippa Newell Andrew M. Jackson Michael J. Gough 《PloS one》2013,8(7)
Expansion of myeloid-lineage leukocytes in tumor-bearing mice has been proposed as a cause of systemic immunosuppression. We demonstrate that radiation therapy of tumors leads to a decline in myeloid cell numbers in the blood and a decrease in spleen size. The frequency of myeloid cells does not decline to the level seen in tumor-free mice: we demonstrate that metastatic disease can prevent myeloid cell numbers from returning to baseline, and that tumor recurrence from residual disease correlates with re-expansion of myeloid lineage cells. Radiation therapy results in increased proliferation of T cells in the spleen and while T cell responses to foreign antigens are not altered by tumor burden or myeloid cell expansion, responses to tumor-associated antigens are increased after radiation therapy. These data demonstrate that myeloid cell numbers are directly linked to primary tumor burden, that this population contracts following radiation therapy, and that radiation therapy may open a therapeutic window for immunotherapy of residual disease. 相似文献
999.
Gareth Ball James P. Boardman Tomoki Arichi Nazakat Merchant Daniel Rueckert A. David Edwards Serena J. Counsell 《PloS one》2013,8(7)
Early neuroimaging may provide a surrogate marker for brain development and outcome after preterm birth. Tract-Based Spatial Statistics (TBSS) is an advanced Diffusion Tensor Image (DTI) analysis technique that is sensitive to the effects of prematurity and may provide a quantitative marker for neuroprotection following perinatal brain injury or preterm birth. Here, we test the sensitivity of TBSS to detect diffuse microstructural differences in the developing white matter of preterm infants at term-equivalent age by modelling a ‘treatment’ effect as a global increase in fractional anisotropy (FA). As proof of concept we compare these simulations to a real effect of increasing age at scan. 3-Tesla, 15-direction diffusion tensor imaging (DTI) was acquired from 90 preterm infants at term-equivalent age. Datasets were randomly assigned to ‘treated’ or ‘untreated’ groups of increasing size and voxel-wise increases in FA were used to simulate global treatment effects of increasing magnitude in all ‘treated’ maps. ‘Treated’ and ‘untreated’ FA maps were compared using TBSS. Predictions from simulated data were then compared to exemplar TBSS group comparisons based on increasing postmenstrual age at scan. TBSS proved sensitive to global differences in FA within a clinically relevant range, even in relatively small group sizes, and simulated data were shown to predict well a true biological effect of increasing age on white matter development. These data confirm that TBSS is a sensitive tool for detecting global group-wise differences in FA in this population. 相似文献
1000.
Synthesis and configurational assay of asymmetric methyl groups 总被引:5,自引:0,他引:5