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21.
Rajagopalan Sridhar Eric C. Stroude W. Rodger Inch 《In vitro cellular & developmental biology. Plant》1979,15(9):685-690
Summary 2-Deoxy-d-glucose (2DG) and 5-thio-d-glucose (5TG) are glucose antimetabolites that are known to be selectively toxic to hypoxic cells grown as single cells or
as monolayer cultures. These analogues were toxic to Chinese hamster V79 cells grown as multicell spheroids even under aerobic
conditions. When spheroids, 500- to 600-μm diameter, were exposed to 7.5mm of these chemicals for 3 days, the number of clonogenic cells per spheroid dropped to 50% for 5-thio-d-glucose and 20% for 2-deoxy-d-glucose, relative to control values. Survivals were reduced to less than 1% when the experiment was repeated in glucose-free
medium. Scanning electron photomicrographs of spheroids treated with 7.5mm of either analogue showed extensive damage to the outer cells. The cell killing observed was much more than could be predicted
on the basis of the hypoxic fraction known to be present in these spheroids. The crowded tumor-like environment may make the
cells vulnerable to the cytotoxic action of glucose analogues and other glycolytic inhibitors.
Supported by the Ontario Cancer Treatment and Research Foundation, London Clinic. 相似文献
22.
Biochemical and biophysical characteristics of diarrhea viruses of human and calf origin. 总被引:40,自引:19,他引:21 下载免费PDF全文
Polyacrylamide gel electrophoretic analysis of purified preparations of human and calf diarrhea viruses indicated eight polypeptide components, or possibly nine in the case of the calf diarrhea virus. Thermal denaturation and analytical studies of the calf diarrhea virus genome showed it to consist of 11 double-stranded segments of RNA. The placing of the human and calf diarrhea viruses together with other similar viruses into a genus separate from reovirus and orbivirus, but within the family Reoviridae, is discussed. 相似文献
23.
The seminal plasma of seven eutherian species, including man, was examined for the presence of free N-acetylaminosugar. Only man had appreciable levels of N-acetylaminosugar in the semen (37-1 mg/100 ml), but in all cases this free N-acetylaminosugar was probably the result of breakdown of polysaccharides by semen glycosidases. High levels of free N-acetylaminosugar thus appear to be peculiar to marsupials. 相似文献
24.
Terence E. Nicholas Rodger G. Johnson Moira A. Lugg Patricia A. Kim 《Life sciences》1978,22(17):1517-1524
Incubation of fetal lung tissue with 0.2 μM 14C-cortisone revealed a 12-fold increase in the rate of reduction of cortisone to cortisol between day 22 and day 30 of gestation in the rabbit. This increase correlated closely with the increase in the rate of incorporation of 14C-choline into total lung lipids during the same period. In light of these findings it would seem inadequate to attempt to relate the plasma cortisol concentration alone with the rate of lung maturation. In addition, one would need consider both the plasma concentration of cortisone and the activity of 11β-hydroxysteroid dehydrogenase (11β-HSD) in the lung. 相似文献
25.
We have studied the binding of β,γ-imido-adenosine-5′-triphosphate to glycerol-extracted insect flight and rabbit back muscle fibres. The binding was at relatively high affinity, of the same quantity as that of other nucleotides, and was inhibited by the presence of ATP. We concluded that imido-ATP bound, without hydrolysis, at the enzymic site of myosin. The mechanical effects of imido-ATP on the glycerol-extracted fibres were measured: concentrations sufficient to bind to myosin caused a small increase in the length of the rigor muscle for a given tension without alteration in the shape of the length-tension diagram. The magnitude of the length change paralleled the binding curve of imido-ATP to the fibre. We concluded that binding caused some change in myosin without its detachment from actin. Electron microscopy and X-ray diffraction studies of glycerol-extracted flight muscle fibres showed an increase in the angle of attachment of myosin to actin when imido-ATP was added. The results are discussed in relation to current concepts of force generation in active muscle. 相似文献
26.
Khanh B. Tran Gregory Gimenez Peter Tsai Sharada Kolekar Euan J. Rodger Aniruddha Chatterjee Anower Jabed Jen‐Hsing Shih Wayne R. Joseph Elaine S. Marshall Qian Wang Cristin G. Print Michael R. Eccles Bruce C. Baguley Peter R. Shepherd 《Pigment cell & melanoma research》2021,34(1):136-143
Melanoma is a disease associated with a very high mutation burden and thus the possibility of a diverse range of oncogenic mechanisms that allow it to evade therapeutic interventions and the immune system. Here, we describe the characterization of a panel of 102 cell lines from metastatic melanomas (the NZM lines), including using whole‐exome and RNA sequencing to analyse genetic variants and gene expression changes in a subset of this panel. Lines possessing all major melanoma genotypes were identified, and hierarchical clustering of gene expression profiles revealed four broad subgroups of cell lines. Immunogenotyping identified a range of HLA haplotypes as well as expression of neoantigens and cancer–testis antigens in the lines. Together, these characteristics make the NZM panel a valuable resource for cell‐based, immunological and xenograft studies to better understand the diversity of melanoma biology and the responses of melanoma to therapeutic interventions. 相似文献
27.
Portia C. Mutevedzi Alison J. Rodger Paul Kowal Makandwe Nyirenda Marie-Louise Newell 《PloS one》2013,8(10)
Background
The association of HIV with chronic morbidity and inflammatory markers (cytokines) in older adults (50+years) is potentially relevant for clinical care, but data from African populations is scarce.Objective
To examine levels of chronic morbidity by HIV and ART status in older adults (50+years) and subsequent associations with selected pro-inflammatory cytokines and body mass index.Methods
Ordinary, ordered and generalized ordered logistic regression techniques were employed to compare chronic morbidity (heart disease (angina), arthritis, stroke, hypertension, asthma and diabetes) and cytokines (Interleukins-1 and -6, C-Reactive Protein and Tumor Necrosis Factor-alpha) by HIV and ART status on a cross-sectional random sample of 422 older adults nested within a defined rural South African population based demographic surveillance.Results
Using a composite measure of all morbidities, controlling for age, gender, BMI, smoking and wealth quintile, HIV-infected individuals on ART had 51% decreased odds (95% CI:0.26-0.92) of current morbidity compared to HIV-uninfected. In adjusted regression, compared to HIV-uninfected, the proportional odds (aPOR) of having elevated inflammation markers of IL6 (>1.56pg/mL) was nearly doubled in HIV-infected individuals on (aPOR 1.84; 95%CI: 1.05-3.21) and not on (aPOR 1.94; 95%CI: 1.11-3.41) ART. Compared to HIV-uninfected, HIV-infected individuals on ART had >twice partial proportional odds (apPOR=2.30;p=0.004) of having non-clinically significant raised hsCRP levels(>1ug/mL); ART-naïve HIV-infected individuals had >double apPOR of having hsCRP levels indicative of increased heart disease risk(>3.9ug/mL;p=0.008).Conclusions
Although HIV status was associated with increased inflammatory markers, our results highlight reduced morbidity in those receiving ART and underscore the need of pro-actively extending these services to HIV-uninfected older adults, beyond mere provision at fixed clinics. Providing health services through regular community chronic disease screening would ensure health care reaches all older adults in need. 相似文献28.
Andrew Speakman Alison Rodger Andrew N. Phillips Richard Gilson Margaret Johnson Martin Fisher Ed Wilkins Jane Anderson Rebecca O’Connell Monica Lascar Kazeem Aderogba Simon Edwards Jeffrey McDonnell Nicky Perry Lorraine Sherr Simon Collins Graham Hart Anne M. Johnson Alec Miners Jonathan Elford Anna-Maria Geretti William J. Burman Fiona C. Lampe 《PloS one》2013,8(10)
Life expectancy for people diagnosed with HIV has improved dramatically however the number of new infections in the UK remains high. Understanding patterns of sexual behaviour among people living with diagnosed HIV, and the factors associated with having condom-less sex, is important for informing HIV prevention strategies and clinical care. In addition, in view of the current interest in a policy of early antiretroviral treatment (ART) for all people diagnosed with HIV in the UK, it is of particular importance to assess whether ART use is associated with increased levels of condom-less sex. In this context the ASTRA study was designed to investigate current sexual activity, and attitudes to HIV transmission risk, in a large unselected sample of HIV-infected patients under care in the UK. The study also gathered background information on demographic, socio-economic, lifestyle and disease-related characteristics, and physical and psychological symptoms, in order to identify other key factors impacting on HIV patients and the behaviours which underpin transmission. In this paper we describe the study rationale, design, methods, response rate and the demographic characteristics of the participants. People diagnosed with HIV infection attending 8 UK HIV out-patient clinics in 2011-2012 were invited to participate in the study. Those who agreed to participate completed a confidential, self-administered pen-and-paper questionnaire, and their latest CD4 count and viral load test results were recorded. During the study period, 5112 eligible patients were invited to take part in the study and 3258 completed questionnaires were obtained, representing a response rate of 64% of eligible patients. The study includes 2248 men who have sex with men (MSM), 373 heterosexual men and 637 women. Future results from ASTRA will be a key resource for understanding HIV transmission within the UK, targeting prevention efforts, and informing clinical care of individuals living with HIV. 相似文献
29.
P. Mark Rodger 《Molecular simulation》2013,39(5-6):263-269
Abstract Attention is drawn to the fact that some of the algorithms used in the simulation of molecular dynamics are less accurate than is commonly believed. In particular, we show that many of the “Verlet-equivalent” integration schemes are not equivalent to the Verlet algorithm, and consequently are not necessarily third order schemes which exhibit exact time-reversal symmetry. Of this class of algorithms, only Beeman's technique is found to generate the optimal positions and velocities for a third order technique. It is also pointed out that the method of constraints introduces errors of O(τ3) into the calculated position, and hence limits the accuracy of simulations that employ this method to second order. 相似文献