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排序方式: 共有419条查询结果,搜索用时 15 毫秒
1.
MORBILLIVIRUS INFECTION IN BOTTLENOSE DOLPHINS: EVIDENCE FOR RECURRENT EPIZOOTICS IN THE WESTERN ATLANTIC AND GULF OF MEXICO 总被引:1,自引:0,他引:1
Pádraig J. Duignan Carol House Daniel K. Odell Randall S. Wells Larry J. Hansen Michael T. Walsh David J. St . Aubin Bert K. Rima Joseph R. Geraci 《Marine Mammal Science》1996,12(4):499-515
Morbillivirus infection is widespread among odontocetes of the western Atlantic and Gulf of Mexico. Serologic evidence of infection in bottlenose dolphins, Tursiops truncatus , was first detected during an epizootic along the mid-Atlantic coast in 1987. Here, we report recurrent epizootics in the coastal dolphin population since at least the early 1980s based on serological surveys and regional stranding frequencies. The first observed epizootic of this series occurred in the Indian and Banana Rivers in 1982 and was followed by others on the mid-Atlantic coast in 1987–1988 and in the Gulf of Mexico between 1992 and 1994. This temporal pattern of infection is likely facilitated by the population size and its fragmentation into relatively discrete coastal communities. Introduction of morbillivirus into a community with a sufficient number of naive hosts may precipitate an epizootic, depending on the potential for transmission within the group. Propagation of an epizootic along the coast is probably determined by frequency of contact between adjacent communities and seasonal migrations.
Morbillivirus antibodies were also detected in serum from offshore bottlenose dolphins. The sero-prevalence in the latter may be higher than in coastal dolphins because of their close association with enzootically infected pilot whales ( Globicephala spp.). Occasional contact between offshore and coastal dolphins may provide an epizootiologic link between pilot whales and coastal dolphin communities. 相似文献
Morbillivirus antibodies were also detected in serum from offshore bottlenose dolphins. The sero-prevalence in the latter may be higher than in coastal dolphins because of their close association with enzootically infected pilot whales ( Globicephala spp.). Occasional contact between offshore and coastal dolphins may provide an epizootiologic link between pilot whales and coastal dolphin communities. 相似文献
2.
Antigenic determinants of measles virus hemagglutinin associated with neurovirulence. 总被引:7,自引:5,他引:2 下载免费PDF全文
U G Liebert S G Flanagan S Lffler K Baczko V ter Meulen B K Rima 《Journal of virology》1994,68(3):1486-1493
The biological activity of monoclonal antibodies specific for the hemagglutinin protein of measles virus strain CAM recognizing six epitope groups according to their binding properties to measles virus strain CAM/R401 was investigated in vivo in our rat model of measles encephalitis. When injected intraperitoneally into measles virus-infected suckling rats, some monoclonal antibodies modified the disease process and prevented the necrotizing encephalopathy seen in untreated animals. The analysis of measles virus brain isolates revealed emergence of variants that resisted neutralization with the passively transferred selecting monoclonal antibody but not with other monoclonal antibodies. Monoclonal antibody escape mutants were also isolated in vitro, and their neurovirulence varied in the animal model. Sequence data from the hemagglutinin gene of measles virus localize a major antigenic surface determinant of the hemagglutinin protein between amino acid residues 368 and 396, which may be functionally important for neurovirulence. The data indicate that the interaction of antibodies with the measles virus H protein plays an important role in the selection of neurovirulent variants. These variants have biological properties different from those of the parent CAM virus. 相似文献
3.
In Bacillus subtilis, uracil (Ura), uridine (Urd), and deoxyuridine (dUrd) are metabolized through pathways similar to those of enteric bacteria. Ura is probably converted to uridine 5'-monophosphate by uridine 5'-monophosphate pyrophosphorylase. More than 95% of dUrd added to cultures is converted to Ura and deoxyribose-1-phosphate. Although dUrd kinase activity is detectable in vitro, this enzyme does not seem to play an important role in the metabolism of dUrd. The metabolism of cytosine (Cyt), cytidine (Cyd), and deoxycytidine (dCyd) in B. subtilis appears to be different from that in enteric bacteria. Cytosine cannot be used by Ura-requiring mutants as pyrimidine source. dCyd is deaminated by dCyd-Cyd deaminase or phosphorylated to dCyd nucleotides by dCyd kinase. Cyd is deaminated by dCyd-Cyd deaminase of phosphorylated by Cyd kinase. This Cyd kinase activity has never been reported for B. subtilis. 相似文献
4.
A number of deoxyribonucleoside-requiring mutants (dns) of Bacillus subtilis were isolated and their growth characteristics and ribonucleotide reductase activities were compared with those of the wild type and of a dna mutant (tsA13). Both tsA13 and dns mutants required the presence of a mixture of deoxyribonucleosides for growth at 45 degrees C but not at 25 degrees C. All the mutant strains tested contained ribonucleotide reductase activity which showed heat sensitivity similar to that of the enzyme from a wild-type strain. The reductase in B. subtilis seemed to reduce ribonucleoside triphosphates in a similar manner to the enzyme in Lactobacillus leichmannii. 相似文献
5.
Koura Jessica Manneh Rima Belarbi Rafik El Khoury Vanessa El Bachawati Makram 《The International Journal of Life Cycle Assessment》2020,25(3):423-442
The International Journal of Life Cycle Assessment - Vegetative roofs (VRs) are fully planted roof spaces that offer aesthetic view, storm water management, sound insulation, energy savings, and... 相似文献
6.
Reavis Zackery W. Mirjankar Nikhil Sarangi Srikant Boyle Stephen H. Kuhn Cynthia M. Matson Wayne R. Babyak Michael A. Matson Samantha A. Siegler Ilene C. Kaddurah‑Daouk Rima Suarez Edward C. Williams Redford B. Grichnik Katherine Stafford‑Smith Mark Georgiades Anastasia 《Metabolomics : Official journal of the Metabolomic Society》2021,17(6):1-13
Metabolomics - Metabolomics applications to the aquaculture research are increasing steadily. The use of standardized proton nuclear magnetic resonance (1H NMR) spectroscopy can provide the... 相似文献
7.
Joseph McEvoy Rebecca A. Baillie Hongjie Zhu Peter Buckley Matcheri S. Keshavan Henry A. Nasrallah George G. Dougherty Jeffrey K. Yao Rima Kaddurah-Daouk 《PloS one》2013,8(7)
There is a critical need for mapping early metabolic changes in schizophrenia to capture failures in regulation of biochemical pathways and networks. This information could provide valuable insights about disease mechanisms, trajectory of disease progression, and diagnostic biomarkers. We used a lipidomics platform to measure individual lipid species in 20 drug-naïve patients with a first episode of schizophrenia (FE group), 20 patients with chronic schizophrenia that had not adhered to prescribed medications (RE group), and 29 race-matched control subjects without schizophrenia. Lipid metabolic profiles were evaluated and compared between study groups and within groups before and after treatment with atypical antipsychotics, risperidone and aripiprazole. Finally, we mapped lipid profiles to n3 and n6 fatty acid synthesis pathways to elucidate which enzymes might be affected by disease and treatment. Compared to controls, the FE group showed significant down-regulation of several n3 polyunsaturated fatty acids (PUFAs), including 20:5n3, 22:5n3, and 22:6n3 within the phosphatidylcholine and phosphatidylethanolamine lipid classes. Differences between FE and controls were only observed in the n3 class PUFAs; no differences where noted in n6 class PUFAs. The RE group was not significantly different from controls, although some compositional differences within PUFAs were noted. Drug treatment was able to correct the aberrant PUFA levels noted in FE patients, but changes in re patients were not corrective. Treatment caused increases in both n3 and n6 class lipids. These results supported the hypothesis that phospholipid n3 fatty acid deficits are present early in the course of schizophrenia and tend not to persist throughout its course. These changes in lipid metabolism could indicate a metabolic vulnerability in patients with schizophrenia that occurs early in development of the disease. 相似文献
8.
Feldheim Kevin A. Jabado Rima W. Chapman Demian D. Cardeñosa Diego Maddox J. Dylan 《Molecular biology reports》2020,47(4):2669-2675
Molecular Biology Reports - Microsatellites are useful in studies of population genetics, sibship, and parentage. Here, we screened for microsatellites from multiple elasmobranch genomic libraries... 相似文献
9.
Rima Ezzeddine Anwar Al-Banaw Artak Tovmasyan James D. Craik Ines Batinic-Haberle Ludmil T. Benov 《The Journal of biological chemistry》2013,288(51):36579-36588
Tetra-cationic Zn(II) meso-tetrakis(N-alkylpyridinium-2 (or -3 or -4)-yl)porphyrins (ZnPs) with progressively increased lipophilicity were synthesized to investigate how the tri-dimensional shape and lipophilicity of the photosensitizer (PS) affect cellular uptake, subcellular distribution, and photodynamic efficacy. The effect of the tri-dimensional shape of the molecule was studied by shifting the N-alkyl substituent attached to the pyridyl nitrogen from ortho to meta and para positions. Progressive increase of lipophilicity from shorter hydrophilic (methyl) to longer amphiphilic (hexyl) alkyl chains increased the phototoxicity of the ZnP PSs. PS efficacy was also increased for all derivatives when the alkyl substituents were shifted from ortho to meta, and from meta to para positions. Both cellular uptake and subcellular distribution of the PSs were affected by the lipophilicity and the position of the alkyl chains on the periphery of the porphyrin ring. Whereas the hydrophilic ZnPs demonstrated mostly lysosomal distribution, the amphiphilic hexyl derivatives were associated with mitochondria, endoplasmic reticulum, and plasma membrane. A comparison of hexyl isomers revealed that cellular uptake and partition into membranes followed the order para > meta > ortho. Varying the position and length of the alkyl substituents affects (i) the exposure of cationic charges for electrostatic interactions with anionic biomolecules and (ii) the lipophilicity of the molecule. The charge, lipophilicity, and the tri-dimensional shape of the PS are the major factors that determine cellular uptake, subcellular distribution, and as a consequence, the phototoxicity of the PSs. 相似文献
10.
Stephen P. Muench Jozef Stec Ying Zhou Gustavo A. Afanador Martin J. McPhillie Mark R. Hickman Patty J. Lee Susan E. Leed Jennifer M. Auschwitz Sean T. Prigge David W. Rice Rima McLeod 《Bioorganic & medicinal chemistry letters》2013,23(12):3551-3555
The enoyl acyl-carrier protein reductase (ENR) enzyme is harbored within the apicoplast of apicomplexan parasites providing a significant challenge for drug delivery, which may be overcome through the addition of transductive peptides, which facilitates crossing the apicoplast membranes. The binding site of triclosan, a potent ENR inhibitor, is occluded from the solvent making the attachment of these linkers challenging. Herein, we have produced 3 new triclosan analogs with bulky A- and B-ring motifs, which protrude into the solvent allowing for the future attachment of molecular transporters for delivery. 相似文献