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11.
Joseph W. Towner 《American journal of botany》1962,49(10):1064-1067
Towner , Joseph W. (U. California, Los Angeles.) Cytogenetics of Tagetes jaliscensis X T. erecta. Amer. Jour. Bot. 49(10): 1064–1067. Illus. 1962.—Although Tagetes jaliscensis and T. erecta are morphologically very distinct, the F1 hybrid between them had normal meiosis (12 bivalents) and was fertile. Segregation in F2 was undisturbed for marker genes on 4 pairs of chromosomes. These facts suggest that T. jaliscensis, like T. erecta, is an A-genome diploid (genome formula A2A2). From plant morphology, the A-subgenome of amphiploid T. patula is regarded as more likely derived from T. erecta than from T. jaliscensis. In T. jaliscensis X erecta F2, disk corolla anthocyanin (R = red) from T. jaliscensis segregated as a simple dominant over the absence of anthocyanin from T. erecta. A chlorophyll defect was determined by duplicate factor recessives. Tubular ray flowers (tu = tubular) segregated as a simple recessive to normal flat rays in the interspecific F2 and in T. erecta. 相似文献
12.
Jonathan C. Guito Joseph B. Prescott Catherine E. Arnold Brian R. Amman Amy J. Schuh Jessica R. Spengler Tara K. Sealy Jessica R. Harmon JoAnn D. Coleman-McCray Kirsten A. Kulcsar Elyse R. Nagle Raina Kumar Gustavo F. Palacios Mariano Sanchez-Lockhart Jonathan S. Towner 《Current biology : CB》2021,31(2):257-270.e5
13.
P. P. K. Ho R. D. Towner M. A. Esterman 《Preparative biochemistry & biotechnology》2013,43(5):597-613
Abstract The fatty acid cyclooxygenase (EC 1.14.99.1) that produces the prostaglandin, thromboxane, and prostacyclin precursor (PGHp), was solubilized from human platelet microsomes in 20 sucrose and 1.0% Triton X-100. The enzyme was purified 300-fold by electrofocusing, Sephadex G-200 gel filtration, and hydrophobic chromatography on ethyl agarose. The cyclooxygenase catalyzed the conversion of arachidonic acid to prostaglandin endoperioxide, PGH2, that was trapped at ?25°C and separated on TLC at ?20°C. PGH2 was hydrolyzed to HHT in acidic pH, or was chemically converted to PGE2 in slightly alkaline pH in the absence of cofactors. The enzyme showed a broad pH optimum in the range of 7–9. Hemin containing substances such as methemoglobin were absolutely required as cofactors, while tryptophan, epinephrine, phenol, and hydro-quinone stimulated the PGH2 formation. Metal ions, such as Zn2+ and Cd2+ inhibited the enzyme reaction at 0.1 to 1 mM. The molecular weight of the purified enzyme was estimated at 79,432 by sodium dodecyl sulfate disc gel electrophoresis at pH 8.0. The properties of the human platelet enzyme was generally similar to the sheep vesicular enzyme in the method of solubilization, pH optimum, and molecular weight. 相似文献
14.
Serena A. Carroll Jonathan S. Towner Tara K. Sealy Laura K. McMullan Marina L. Khristova Felicity J. Burt Robert Swanepoel Pierre E. Rollin Stuart T. Nichol 《Journal of virology》2013,87(5):2608-2616
Viruses in the Ebolavirus and Marburgvirus genera (family Filoviridae) have been associated with large outbreaks of hemorrhagic fever in human and nonhuman primates. The first documented cases occurred in primates over 45 years ago, but the amount of virus genetic diversity detected within bat populations, which have recently been identified as potential reservoir hosts, suggests that the filoviruses are much older. Here, detailed Bayesian coalescent phylogenetic analyses are performed on 97 whole-genome sequences, 55 of which are newly reported, to comprehensively examine molecular evolutionary rates and estimate dates of common ancestry for viruses within the family Filoviridae. Molecular evolutionary rates for viruses belonging to different species range from 0.46 × 10−4 nucleotide substitutions/site/year for Sudan ebolavirus to 8.21 × 10−4 nucleotide substitutions/site/year for Reston ebolavirus. Most recent common ancestry can be traced back only within the last 50 years for Reston ebolavirus and Zaire ebolavirus species and suggests that viruses within these species may have undergone recent genetic bottlenecks. Viruses within Marburg marburgvirus and Sudan ebolavirus species can be traced back further and share most recent common ancestors approximately 700 and 850 years before the present, respectively. Examination of the whole family suggests that members of the Filoviridae, including the recently described Lloviu virus, shared a most recent common ancestor approximately 10,000 years ago. These data will be valuable for understanding the evolution of filoviruses in the context of natural history as new reservoir hosts are identified and, further, for determining mechanisms of emergence, pathogenicity, and the ongoing threat to public health. 相似文献
15.
Rheal A. Towner Nataliya Smith Debra Saunders Patricia Coutinho De Souza Leah Henry Florea Lupu Robert Silasi-Mansat Marilyn Ehrenshaft Ronald P. Mason Sandra E. Gomez-Mejiba Dario C. Ramirez 《生物化学与生物物理学报:疾病的分子基础》2013,1832(12):2153-2161
Free radicals play a major role in gliomas. By combining immuno-spin-trapping (IST) and molecular magnetic resonance imaging (mMRI), in vivo levels of free radicals were detected within mice bearing orthotopic GL261 gliomas. The nitrone spin trap DMPO (5,5-dimethyl pyrroline N-oxide) was administered prior to injection of an anti-DMPO probe (anti-DMPO antibody covalently bound to a bovine serum albumin (BSA)–Gd (gadolinium)-DTPA (diethylene triamine penta acetic acid)–biotin MRI contrast agent) to trap tumor-associated free radicals. mMRI detected the presence of anti-DMPO adducts by either a significant sustained increase (p < 0.001) in MR signal intensity or a significant decrease (p < 0.001) in T1 relaxation, measured as %T1 change. In vitro assessment of the anti-DMPO probe indicated a significant decrease (p < 0.0001) in T1 relaxation in GL261 cells that were oxidatively stressed with hydrogen peroxide, compared to controls. The biotin moiety of the anti-DMPO probe was targeted with fluorescently-labeled streptavidin to locate the anti-DMPO probe in excised brain tissues. As a negative control a non-specific IgG antibody covalently bound to the albumin–Gd-DTPA–biotin construct was used. DMPO adducts were also confirmed in tumor tissue from animals administered DMPO, compared to non-tumor brain tissue. GL261 gliomas were found to have significantly increased malondialdehyde (MDA) protein adducts (p < 0.001) and 3-nitrotyrosine (3-NT) (p < 0.05) compared to normal mouse brain tissue, indicating increased oxidized lipids and proteins, respectively. Co-localization of the anti-DMPO probe with either 3-NT or 4-hydroxynonenal was also observed. This is the first report regarding the detection of in vivo levels of free radicals from a glioma model. 相似文献
16.
Ronan A. Lyons Denise Kendrick Elizabeth M. L. Towner Carol Coupland Mike Hayes Nicola Christie Judith Sleney Sarah Jones Richard Kimberlee Sarah E. Rodgers Samantha Turner Mariana Brussoni Yana Vinogradova Tinnu Sarvotham Steven Macey 《PloS one》2013,8(4)
Objective
To determine whether advocacy targeted at local politicians leads to action to reduce the risk of pedestrian injury in deprived areas.Design
Cluster randomised controlled trial.Setting
239 electoral wards in 57 local authorities in England and Wales.Participants
617 elected local politicians.Interventions
Intervention group politicians were provided with tailored information packs, including maps of casualty sites, numbers injured and a synopsis of effective interventions.Main outcome measures
25–30 months post intervention, primary outcomes included: electoral ward level: percentage of road traffic calmed; proportion with new interventions; school level: percentage with 20 mph zones, Safe Routes to School, pedestrian training or road safety education; politician level: percentage lobbying for safety measures. Secondary outcomes included politicians’ interest and involvement in injury prevention, and facilitators and barriers to implementation.Results
Primary outcomes did not significantly differ: % difference in traffic calming (0.07, 95%CI: −0.07 to 0.20); proportion of schools with 20 mph zones (RR 1.47, 95%CI: 0.93 to 2.32), Safe Routes to School (RR 1.34, 95%CI: 0.83 to 2.17), pedestrian training (RR 1.23, 95%CI: 0.95 to 1.61) or other safety education (RR 1.16, 95%CI: 0.97 to 1.39). Intervention group politicians reported greater interest in child injury prevention (RR 1.09, 95%CI 1.03 to 1.16), belief in potential to help prevent injuries (RR 1.36, 95%CI 1.16 to 1.61), particularly pedestrian safety (RR 1.55, 95%CI 1.19 to 2.03). 63% of intervention politicians reported supporting new pedestrian safety schemes. The majority found the advocacy information surprising, interesting, effectively presented, and could identify suitable local interventions.Conclusions
This study demonstrates the feasibility of an innovative approach to translational public health by targeting local politicians in a randomised controlled trial. The intervention package was positively viewed and raised interest but changes in interventions were not statistically significance. Longer term supported advocacy may be needed.Trial Registration
Current Controlled Trials ISRCTN91381117 相似文献17.
Viswanathan Rajagopalan Youhua Zhang Kaie Ojamaa Yue-feng Chen Alessandro Pingitore Christine J. Pol Debra Saunders Krithika Balasubramanian Rheal A. Towner A. Martin Gerdes 《PloS one》2016,11(3)
Background
A large body of evidence suggests that thyroid hormones (THs) are beneficial for the treatment of cardiovascular disorders. We have shown that 3 days of triiodo-L-thyronine (T3) treatment in myocardial infarction (MI) rats increased left ventricular (LV) contractility and decreased myocyte apoptosis. However, no clinically translatable protocol is established for T3 treatment of ischemic heart disease. We hypothesized that low-dose oral T3 will offer safe therapeutic benefits in MI.Methods and Results
Adult female rats underwent left coronary artery ligation or sham surgeries. T3 (~6 μg/kg/day) was available in drinking water ad libitum immediately following MI and continuing for 2 month(s) (mo). Compared to vehicle-treated MI, the oral T3-treated MI group at 2 mo had markedly improved anesthetized Magnetic Resonance Imaging-based LV ejection fraction and volumes without significant negative changes in heart rate, serum TH levels or heart weight, indicating safe therapy. Remarkably, T3 decreased the incidence of inducible atrial tachyarrhythmias by 88% and improved remodeling. These were accompanied by restoration of gene expression involving several key pathways including thyroid, ion channels, fibrosis, sympathetic, mitochondria and autophagy.Conclusions
Low-dose oral T3 dramatically improved post-MI cardiac performance, decreased atrial arrhythmias and cardiac remodeling, and reversed many adverse changes in gene expression with no observable negative effects. This study also provides a safe and effective treatment/monitoring protocol that should readily translate to humans. 相似文献18.
METTE SERINE WESMAJERVI TEKLE TAFESE J
RGEN STENVIK KJERSTI TURID FJALESTAD B
RGE DAMSGRD MADJID DELGHANDI 《Molecular ecology resources》2007,7(1):138-140
One hundred and fifty random clones from an enriched genomic library of Atlantic cod were sequenced. Primer pairs were designed for 15 microsatellites containing perfect di‐, tri‐, tetra‐ and hexanucleotide repeats and characterized in 96 unrelated fish. Eight markers were successfully amplified, with the number of alleles ranging from two to nine per locus and observed heterozygosity ranging from 0.341 to 0.977. Loci Gmo‐G13 and Gmo‐G14 had a significant excess of homozygotes. All loci conformed to the Hardy–Weinberg equilibrium. Genetic linkage disequilibrium analysis between all pairs of the loci showed no significant departure from the null hypothesis between any of the loci. 相似文献
19.
Human kallikrein hK3 (prostate-specific antigen) is a chymotrypsin-like serine protease which is widely used in the diagnosis of prostate cancer. Assays of the enzymatic activity of hK3 in extracellular fluids have been limited by a lack of sensitive synthetic substrates. This report describes the design of a series of internally quenched fluorescent peptides containing an amino acid sequence based on preferential hK3 cleavage sites in semenogelins. Those were identified by 2-D gel electrophoresis analysis and N-terminal sequencing of semenogelin fragments generated by ex vivo proteolysis in freshly ejaculated semen. These peptides were cleaved by hK3 at the C-terminal of certain tyrosyl or glutaminyl residues with k(cat)/K(m) values of 15000-60000 M(-1) s(-1). The substrate Abz-SSIYSQTEEQ-EDDnp was cleaved at the Tyr-Ser bond with a specificity constant k(cat)/K(m) of 60000 M(-1) s(-1), making it the best substrate for hK3 described to date. 相似文献
20.
Chintamani Sharma R Badran R Singhal V Saxena S Bansal A 《World journal of surgical oncology》2003,1(1):13