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51.
Sparks AK 《Journal of invertebrate pathology》2005,89(1):67-77
This paper discusses diseases of commercially important non-insect invertebrates from both a historical and a personal perspective. Early studies of curious scientists such as Metchnikoff using invertebrate systems led to important discoveries with much wider impact. As commercial culture of oysters, shrimp, and other invertebrates grew, so did studies of their diseases. Here, the impact of pioneering scientists and important new techniques on our understanding of these diseases is described. 相似文献
52.
Woods YL Xirodimas DP Prescott AR Sparks A Lane DP Saville MK 《The Journal of biological chemistry》2004,279(48):50157-50166
Here we demonstrate a novel p53-independent interaction between the nucleolar tumor suppressors, p14 Arf and Werners helicase (WRN). Binding of p14 Arf to WRN is multivalent and resembles the binding of p14 Arf to Mdm2. Residues 2-14 and 82-101 of p14 Arf and residues in the central region and C terminus of WRN have particular importance for binding. p14 Arf promotes small ubiquitin-like modifier (SUMO) modification of WRN in a synergistic manner with the SUMO-conjugating enzyme, UBCH9. p14 Arf causes redistribution of WRN within the nucleus, and this effect is reversed by expression of a SUMO-specific protease, thus implicating the SUMO conjugation pathway in WRN re-localization. We establish that the ability to promote SUMO conjugation is a general property of the p14 Arf tumor suppressor. 相似文献
53.
Objective: Previous research has addressed the relationship between BMI and chronic disease in primary care; however, little has been done with regard to the association between obesity and depression in primary care. The purpose of this paper is to assess the relationship between obesity and chronic conditions including depression. Research Methods and Procedures : Data from primary care patients seen at a university‐based family medicine clinic in the southeastern United States were extracted for the time between January 1, 1999 and January 1, 2002. Data extracted included most recent height and weight, age, ethnicity, pregnancy status, number of office visits, blood pressure, cholesterol, hemoglobin A1C, current diagnoses, and medications. Results : A total of 8197 patients were included in the analysis. Sixty‐nine percent of patients seen in a 3‐year period were either overweight or obese. Comparing blood pressure, cholesterol, diagnoses, and medications between BMI groups found differences in virtually all categories. Diagnoses of high cholesterol, hypertension, diabetes, and depression significantly increased for obese patients. Discussion : Obese patients are over‐represented in primary care, and this over‐representation of obesity correlates with several diagnoses, including depression. Depression is a chronic disease that may interfere with health‐related behaviors and must be addressed within the health care system. 相似文献
54.
55.
Synchrony in the phenology of a culturally iconic spring flower 总被引:1,自引:0,他引:1
Sparks TH Mizera T Wójtowicz W Tryjanowski P 《International journal of biometeorology》2012,56(2):407-409
We examine the flowering phenology of the cultural iconic Spring Snowflake Leucojum vernum, a considerable tourist attraction, recorded from two sites in western Poland. Flowering dates at the two sites were closely
correlated but about 6 days later at the more natural area. The end of flowering was associated with the start of canopy leafing.
Early flowering was related to a longer flowering season which may benefit ecotourism under future climate warming. 相似文献
56.
In arid regions, biomes particularly responsive to climate change, mosses play an important biogeochemical role as key components of biocrusts. Using the biocrust moss Syntrichia caninervis collected from the Nevada Desert Free Air CO2 Enrichment Facility, we examined the physiological effects of 10 years of exposure to elevated CO2, and the effect of high temperature events on the photosynthetic performance of moss grown in CO2‐enriched air. Moss exposed to elevated CO2 exhibited a 46% decrease in chlorophyll, a 20% increase in carbon and no difference in either nitrogen content or photosynthetic performance. However, when subjected to high temperatures (35–40°C), mosses from the elevated CO2 environment showed higher photosynthetic performance and photosystem II (PSII) efficiency compared to those grown in ambient conditions, potentially reflective of a shift in nitrogen allocation to components that offer a higher resistance of PSII to heat stress. This result suggests that mosses may respond to climate change in markedly different ways than vascular plants, and observed CO2‐induced photosynthetic thermotolerance in S. caninervis will likely have consequences for future desert biogeochemistry. 相似文献
57.
Chien-Min Hung Luisa Garcia-Haro Cynthia A. Sparks David A. Guertin 《Cold Spring Harbor perspectives in biology》2012,4(12)
The mechanistic target of rapamycin (mTOR) kinase is a conserved regulator of cell growth, proliferation, and survival. In cells, mTOR is the catalytic subunit of two complexes called mTORC1 and mTORC2, which have distinct upstream regulatory signals and downstream substrates. mTORC1 directly senses cellular nutrient availability while indirectly sensing circulating nutrients through growth factor signaling pathways. Cellular stresses that restrict growth also impinge on mTORC1 activity. mTORC2 is less well understood and appears only to sense growth factors. As an integrator of diverse growth regulatory signals, mTOR evolved to be a central signaling hub for controlling cellular metabolism and energy homoeostasis, and defects in mTOR signaling are important in the pathologies of cancer, diabetes, and aging. Here we discuss mechanisms by which each mTOR complex might regulate cell survival in response to metabolic and other stresses.The mechanistic target of rapamycin (mTOR) is a highly conserved serine/threonine protein kinase belonging to the phosphatidylinositol kinase-related kinase (PIKK) family and in mammalian cells is a central regulator of cell growth, proliferation, and survival (for review, see Sengupta et al. 2010; Zoncu et al. 2010). As its name implies, mTOR is the target of the naturally occurring compound rapamycin, which in association with the FK506-binding protein (FKBP12) is an allosteric inhibitor of mTOR. Although rapamycin is now known to only partially inhibit mTOR activity, derivatives of the drug have important clinical applications in oncology, in preventing restenosis after angioplasty, and as an immunosuppressant following organ transplants. 相似文献
58.
Taneja V Behrens M Basal E Sparks J Griffiths MM Luthra H David CS 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(4):2869-2877
In humans, HLA-DR alleles sharing amino acids at the third hypervariable region with DRB1*0401(shared epitope) are associated with a predisposition to rheumatoid arthritis, whereas DRB1*0402 is not associated with such a predisposition. Both DRB1*0402 and DRB1*0401 occur in linkage with DQ8 (DQB1*0302). We have previously shown that transgenic (Tg) mice expressing HLA-DRB1*0401 develop collagen-induced arthritis. To delineate the role of "shared epitope" and gene complementation between DR and DQ in arthritis, we generated DRB1*0402, DRB1*0401.DQ8, and DRB1*0402.DQ8 Tg mice lacking endogenous class II molecules, AE(o). DRB1*0402 mice are resistant to develop arthritis. In double-Tg mice, the DRB1*0401 gene contributes to the development of collagen-induced arthritis, whereas DRB1*0402 prevents the disease. Humoral response to type II collagen is not defective in resistant mice, although cellular response to type II collagen is lower in *0402 mice compared with *0401 mice. *0402 mice have lower numbers of T cells in thymus compared with *0401 mice, suggesting that the protective effect could be due to deletion of autoreactive T cells. Additionally, DRB1*0402 mice have a higher number of regulatory T cells and show increased activation-induced cell death, which might contribute toward protection. In DRB1*0401.DQ8 mice, activated CD4(+) T cells express class II genes and can present DR4- and DQ8-restricted peptides in vitro, suggesting a role of class II(+) CD4 T cells locally in the joints. The data suggest that polymorphism in DRB1 genes determines predisposition to develop arthritis by shaping the T cell repertoire in thymus and activating autoreactive or regulatory T cells. 相似文献
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60.
Baculoviruses are widely used both as protein expression vectors and as insect pest control agents. . This video shows how lepidopteran larvae can be infected with microapplicator techniques in the gut with baculovirus polyhedra and in the hemolymph with budded virus. This accompanying Springer Protocols section provides an overview of the baculovirus lifecycle and use of baculoviruses as insecticidal agents. Formulation and application of baculoviruses for pest control purposes are described elsewhere.Download video file.(127M, mp4) 相似文献