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891.
Schaeffer SW Bhutkar A McAllister BF Matsuda M Matzkin LM O'Grady PM Rohde C Valente VL Aguadé M Anderson WW Edwards K Garcia AC Goodman J Hartigan J Kataoka E Lapoint RT Lozovsky ER Machado CA Noor MA Papaceit M Reed LK Richards S Rieger TT Russo SM Sato H Segarra C Smith DR Smith TF Strelets V Tobari YN Tomimura Y Wasserman M Watts T Wilson R Yoshida K Markow TA Gelbart WM Kaufman TC 《Genetics》2008,179(3):1601-1655
The sequencing of the 12 genomes of members of the genus Drosophila was taken as an opportunity to reevaluate the genetic and physical maps for 11 of the species, in part to aid in the mapping of assembled scaffolds. Here, we present an overview of the importance of cytogenetic maps to Drosophila biology and to the concepts of chromosomal evolution. Physical and genetic markers were used to anchor the genome assembly scaffolds to the polytene chromosomal maps for each species. In addition, a computational approach was used to anchor smaller scaffolds on the basis of the analysis of syntenic blocks. We present the chromosomal map data from each of the 11 sequenced non-Drosophila melanogaster species as a series of sections. Each section reviews the history of the polytene chromosome maps for each species, presents the new polytene chromosome maps, and anchors the genomic scaffolds to the cytological maps using genetic and physical markers. The mapping data agree with Muller's idea that the majority of Drosophila genes are syntenic. Despite the conservation of genes within homologous chromosome arms across species, the karyotypes of these species have changed through the fusion of chromosomal arms followed by subsequent rearrangement events. 相似文献
892.
Incorporation of ethanol (1.0 or 1.25 M) into exponential-phase cultures of Saccharomyces cerevisiae NCYC 366 growing anaerobically in a medium supplemented with ergosterol and an unsaturated fatty acid caused a retardation in growth rate, which was greater when the medium contained oleic rather than linoleic acid. Ethanol incorporation led to an immediate drop in growth rate, and ethanol-containing cultures grew at the slower rate for at least 10 h. Incorporation of ethanol (0.5 M) into buffered (pH 4.5) cell suspensions containing d-[6-3H] glucose, d-[1-14C] glucosamine, l-[U-14C] lysine or arginine, or KH2
32PO4 lowered the rate of solute accumulation by cells. Rates of accumulation of glucose, lysine and arginine were retarded to a greater extent when cells had been grown in the presence of oleic rather than linoleic acid. This difference was not observed with accumulation of phosphate. Ethanol was extracted from exponential-phase cells by four different methods. Cells grown in the presence of linoleic acid contained a slightly, but consistently, lower concentration of ethanol than cells grown in oleic acid-containing medium. The ethanol concentration in cells was 5–7 times greater than that in the cell-free medium. 相似文献
893.
Herpes Simplex Virus Type 1 Infection of Isogenic Epstein-Barr Virus Genome-Negative and -Positive Burkitt''s Lymphoma-Derived Cell Lines 下载免费PDF全文
The Epstein-Barr virus (EBV) genome-negative Burkitt's lymphoma-derived cell lines BJAB and Ramos and their in vitro EBV-converted sublines BJAB-B1, BJAB-A5, BJAB-B95-8, and AW-Ramos were infected with high multiplicities of herpes simplex virus type 1 (HSV-1; 10 to 70 PFU/cell). Cultures were monitored for cell growth and HSV-1 DNA synthesis. EBV-converted BJAB cultures were more permissive for HSV-1 infection than BJAB cultures. Significant cell killing and HSV-1 DNA synthesis were observed during the first 48 h of infection in the EBV-converted BJAB cultures but not in the BJAB cultures. The EBV-converted BJAB-B1 cell line contains an appreciable fraction of EBV-negative cells. Therefore, it was cloned. EBV-positive and -negative cells were identified by using EBV-determined nuclear antigen anti-complement immunofluorescence. Two types of subclones were identified: (i) those which contained both EBV-determined nuclear antigen-positive and -negative cells and (ii) those which contained only EBV-determined nuclear antigen-negative cells. When levels of HSV-1 DNA synthesis were measured in these subclones, it was found that the former were more permissive for HSV-1 infection than the latter. Thus, the presence of the EBV genome in BJAB cells correlates with increased permissiveness of these cells for HSV-1 during the first 48 h of infection. Nonetheless, persistent HSV-1 infections were established in both BJAB and EBV-converted BJAB-B1 cultures. No differences in extent of permissiveness for HSV-1 infection were found for Ramos and EBV-converted AW-Ramos cells. 相似文献
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895.
Saponins are glycosidic compounds present in many edible and inedible plants. They exhibit potent biological activities in mammalian systems, including several beneficial effects such as anti-inflammation and immunomodulation. In this study, we investigated the effects of seven platycodin saponins on the activities of inducible nitric oxide synthase (iNOS) and cyclooxygenase II (COX-2) in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. We found that 2"-O-acetyl polygalacin D (S1), platycodin A (S2), platycodin D (S3), and polygalacin D (S6) inhibited LPS-induced NO production in a concentration-dependent manner. Furthermore, these compounds inhibited the expression of LPS-induced iNOS and COX-2 protein and mRNA without an appreciable cytotoxic effect on RAW 264.7 macrophages, and could suppress induction by LPS of pro-inflammatory cytokines such as prostaglandin E2 (PGE2). Treatment with these compounds of RAW 264.7 cells transfected with a reporter construct indicated a reduced level of LPS-induced nuclear factor-kappaB (NF-kappaB) activity and effectively lowered NF-kappaB binding as measured by electrophoretic mobility shift assay (EMSA). The suppression of NF-kappaB activation appears to occur through the prevention of inhibitor kappaB (IkappaB) degradation. In vivo, platycodin saponin mixture (PS) and S3 protected mice from the lethal effects of LPS. The 89% lethality induced by LPS/galactosamine was reduced to 60% and 50% when PS and S3, respectively, were administered simultaneously with LPS. These results suggest that the main inhibitory mechanism of the platycodin saponins may be the reduction of iNOS and COX-2 gene expression through blocking of NF-kappaB activation. 相似文献
896.
Shaw SJ 《Medical anthropology quarterly》2005,19(3):290-309
Over the last 20 years, the concept of culturally appropriate health care has been gradually gaining popularity in medicine and public health. In calling for health care that is culturally appropriate, minority groups seek political recognition of often racialized constructions of cultural difference as they intervene in health care planning and organization. Based on interview narratives from people involved in community organizing to establish a federally funded community health center in a mid-size New England city, I chart the emergence of a language of "culturally appropriate health care" in language used to justify the need for a health center. An identity model of recognition underlies the call for ethnic resemblance between patient and provider seen in many culturally appropriate care programs. I contrast this model of health care with earlier calls for community access and control by activists in the 1970s and explore the practical and theoretical implications of each approach. 相似文献
897.
Addictive drugs and their relationship with infectious diseases 总被引:4,自引:0,他引:4
The use of drugs of abuse, both recreationally and medicinally, may be related to serious public health concerns. There is a relationship between addictive drugs of abuse such as alcohol and nicotine in cigarette smoke, as well as illegal drugs such as opiates, cocaine and marijuana, and increased susceptibility to infections. The nature and mechanisms of immunomodulation induced by such drugs of abuse are described in this review. The effects of opiates and marijuana, using animal models as well as in vitro studies with immune cells from experimental animals and humans, have shown that immunomodulation induced by these drugs is mainly receptor-mediated, either directly by interaction with specific receptors on immune cells or indirectly by reaction with similar receptors on cells of the nervous system. Similar studies also show that cocaine and nicotine have marked immunomodulatory effects, which are mainly receptor-mediated. Both cocaine, an illegal drug, and nicotine, a widely used legal addictive component of cigarettes, are markedly immunomodulatory and increase susceptibility to infection. The nature and mechanism of immunomodulation induced by alcohol, the most widely used addictive substance of abuse, are similar but immunomodulatory effects, although not receptor-mediated. The many research studies on the effects of these drugs on immunity and increased susceptibility to infectious diseases, including AIDS, are providing a better understanding of the complex interactions between immunity, infections and substance abuse. 相似文献
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