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91.
DR. JOHN LEE 《The Journal of eukaryotic microbiology》1993,40(4):395-410
ABSTRACT. Many advances have been made in our knowledge of the biology of foraminifera over the past several decades. Fine structural, biophysical, and molecular biological studies have shown that the most prominent components of their distinctive bidirectional granuloreliculopods are bundles of micro tubules linked by crossbridges to each other, as well as to membrane-bound organelles and the plasma membrane. the microtubules ratchet past each other as dynein transduces the free energy of ATP to produce pseudopodal movements. In spite of the fact that there are over 40,000 described species of living and fossil species of foraminifera, there have been many recent exciting discoveries of new species and groups. New casting techniques are providing us with greater understanding of the complexities and functional aspects of form in the group. Significant advances are being made in understanding the distribution and energetics of deep-sea forms. Larger and planktonic foraminifera are the hosts for a particularly diverse range of endosymbiotic algae, including dinoflagellates, chlorophytes, unicellular rhodophytes, and diatoms. Chloroplast husbandry also occurs. Significant research effort has been expended yielding us considerable insight into various aspects of the endosymbiotic phenomenon. A unified conceptual framework has been drawn to help us understand the life cycle options found in foraminifera. 相似文献
92.
Exclusion of Usher syndrome gene from much of chromosome 4 总被引:1,自引:0,他引:1
R J Smith J D Holcomb S P Daiger C T Caskey M Z Pelias B R Alford D D Fontenot J F Hejtmancik 《Cytogenetics and cell genetics》1989,50(2-3):102-106
Usher syndrome is an autosomal recessive disease characterized by dual sensory impairments; affected individuals are born with a sensorineural hearing loss and ultimately lose their sight as retinitis pigmentosa develops. Conventional protein markers previously tested in a Louisiana Acadian kindred suggested tentative linkage to vitamin D-binding protein on chromosome 4. DNA linkage studies do not confirm this linkage relationship and exclude much of chromosome 4 as the site of the Usher syndrome gene in these families. 相似文献
93.
Russell L Legg Jessica R Tolman Cameron T Lovinger Edwin D Lephart Kenneth DR Setchell Merrill J Christensen 《Reproductive biology and endocrinology : RB&E》2008,6(1):57
Background
High dietary intake of selenium or soybean isoflavones reduces prostate cancer risk. These components each affect androgen-regulated gene expression. The objective of this work was to determine the combined effects of selenium and isoflavones on androgen-regulated gene expression in rat prostate. 相似文献94.
Hasmik Keshishian E Robert McDonald III Filip Mundt Randy Melanson Karsten Krug Dale A Porter Luke Wallace Dominique Forestier Bokang Rabasha Sara E Marlow Judit JaneValbuena Ellen Todres Harrison Specht Margaret Lea Robinson Pierre M Jean Beltran Ozgun Babur Meagan E Olive Javad Golji Eric Kuhn Michael Burgess Melanie A MacMullan Tomas Rejtar Karen Wang DR Mani Shankha Satpathy Michael A Gillette William R Sellers Steven A Carr 《Molecular systems biology》2021,17(9)
Reliable methods to quantify dynamic signaling changes across diverse pathways are needed to better understand the effects of disease and drug treatment in cells and tissues but are presently lacking. Here, we present SigPath, a targeted mass spectrometry (MS) assay that measures 284 phosphosites in 200 phosphoproteins of biological interest. SigPath probes a broad swath of signaling biology with high throughput and quantitative precision. We applied the assay to investigate changes in phospho‐signaling in drug‐treated cancer cell lines, breast cancer preclinical models, and human medulloblastoma tumors. In addition to validating previous findings, SigPath detected and quantified a large number of differentially regulated phosphosites newly associated with disease models and human tumors at baseline or with drug perturbation. Our results highlight the potential of SigPath to monitor phosphoproteomic signaling events and to nominate mechanistic hypotheses regarding oncogenesis, response, and resistance to therapy. 相似文献
95.
Lihong?BuEmail author Kenneth?DR?Setchell Edwin?D?Lephart 《Reproductive biology and endocrinology : RB&E》2005,3(1):58
Background
Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. Few studies have examined the nociception and stress hormone responses after consumption of soy isoflavones. 相似文献96.
Bill JR Mack DG Falta MT Maier LA Sullivan AK Joslin FG Martin AK Freed BM Kotzin BL Fontenot AP 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(10):7029-7037
Chronic beryllium disease (CBD) is characterized by a CD4+ T cell alveolitis and granulomatous inflammation in the lung. Genetic susceptibility to this disease has been linked with HLA-DP alleles, particularly those possessing a glutamic acid at position 69 (Glu69) of the beta-chain. However, 15% of CBD patients do not possess a Glu69-containing HLA-DP allele, suggesting that other MHC class II alleles may be involved in disease susceptibility. In CBD patients without a Glu69-containing HLA-DP allele, an increased frequency of HLA-DR13 alleles has been described, and these alleles possess a glutamic acid at position 71 of the beta-chain (which corresponds to position 69 of HLA-DP). Thus, we hypothesized that beryllium presentation to CD4+ T cells was dependent on a glutamic acid residue at the identical position of both HLA-DP and -DR. The results show that HLA-DP Glu69- and HLA-DR Glu71-expressing molecules are capable of inducing beryllium-specific proliferation and IFN-gamma expression by lung CD4+ T cells. Using fibroblasts expressing mutated HLA-DP2 and -DR13 molecules, beryllium recognition was dependent on the glutamic acid at position 69 of HLA-DP and 71 of HLA-DR, suggesting a critical role for this amino acid in beryllium presentation to Ag-specific CD4+ T cells. Thus, these results demonstrate that a single amino acid residue of the MHC class II beta-chain dictates beryllium presentation and potentially, disease susceptibility. 相似文献
97.
DR Suresh Vamseedhar Annam K Pratibha BV Maruti Prasad 《Journal of biomedical science》2009,16(1):61-4
Background
Oxidative stress induced by the production of reactive oxygen species may play a critical role in the stimulation of HIV replication and the development of immunodeficiency. This study was conducted as there are limited and inconclusive studies on the significance of a novel early marker of oxidative stress which can reflect the total antioxidant capacity in HIV patients, 相似文献98.
M.B. Fontenot M.W. Musso S.L. Watson & G.M. Anderson 《Journal of medical primatology》2010,39(1):24-31
Background Assessment of cerebrospinal (CSF) monoamine metabolites 5-hydroxyindoeacetic acid (5-HIAA) and homovanillic acid (HVA), and the serotonin precursor tryptophan (TRP), in chimpanzees may help in understanding the neurobiology underlying aggressive, impulsive behavior in humans and non-human primates.
Methods Two CSF samples were obtained from 11 peripubertal chimpanzees 8 months apart and were assayed for monoamine metabolite and TRP concentrations.
Results Substantial inter-individual stability was observed for 5-HIAA (n = 11; r = 0.83, P < 0.001) and HVA (r = 0.91, P < 0.001). Females had significantly higher concentrations of 5-HIAA compared to males (F1,8 = 7.31; P < 0.05). Levels of 5-HIAA (r = −0.62, P < 0.05), HVA (r = −0.86, P < 0.001) and TRP levels (r = −0.67; P < 0.05) decreased with age.
Conclusion Close parallels were observed between chimpanzees and humans with respect to absolute levels, sex effects, ontogeny, and 5-HIAA-HVA correlations, supporting the potential utility of the measures in understanding relationships between monoamine functioning and behavior in chimpanzees and humans. 相似文献
Methods Two CSF samples were obtained from 11 peripubertal chimpanzees 8 months apart and were assayed for monoamine metabolite and TRP concentrations.
Results Substantial inter-individual stability was observed for 5-HIAA (n = 11; r = 0.83, P < 0.001) and HVA (r = 0.91, P < 0.001). Females had significantly higher concentrations of 5-HIAA compared to males (F
Conclusion Close parallels were observed between chimpanzees and humans with respect to absolute levels, sex effects, ontogeny, and 5-HIAA-HVA correlations, supporting the potential utility of the measures in understanding relationships between monoamine functioning and behavior in chimpanzees and humans. 相似文献
99.
Thirty-four cytochrome P-450 sequences from one bacterial and six
vertebrate species have been aligned with the aid of a computer alignment
algorithm. Phylogenetic trees were constructed using the
unweighted-pair-group and neighbor-joining methods. The two trees differed
at only a single branch point near the base of the tree. The cytochrome
P-450 superfamily of proteins clustered into eight families and contained
16 gene-duplication events. The first gene duplication occurred
approximately 1,360 Myr before the present (Mybp) and gave rise to
cytochrome P-450s found in two different cellular organelles, the
mitochondria and the endoplasmic reticulum. Both groups utilize cholesterol
or its metabolites as substrates, implying that cholesterol existed greater
than 1,360 Mybp. The fourth gene duplication (approximately 900 Mybp) gave
rise to the drug-metabolizing P-450s. These proteins aid in the
detoxification of foreign chemicals, as opposed to the metabolism of
endogenous compounds. The importance of the capacity to metabolize drugs is
reflected in 11 further gene duplications occurring in this lineage. The
first occurred approximately 800 Mybp and gave rise to the two major P-450
families, the phenobarbital and 3-methylcholanthrene families. An apparent
increase in the rate of cytochrome P-450 evolution is noted between the
bird-mammal divergence (300 Mybp) and the mammalian radiation (75 Mybp).
相似文献
100.