The number of angiosperm species for which nuclear DNA amount estimates have been made has nearly trebled since the last collected lists of such values were published, and therefore, publication of a more comprehensive list is over due. This paper lists absolute nuclear DNA amounts for 753 angiosperm species. The dats were assembled primarily for reference purposes, and so the species are listed in alphabetical order, as this was felt to be more helpful to cyto- and biochemists whom, it is anticipated, will be among its major users. The paper also reviews aspects of the history, nomenclature, methods, accuracy and problems of nuclear DNA estimation in angiosperms. No attempt is made to reconsider those aspects of nuclear DNA estimation which have been fully revised previously, although the bibliography of such aspects is given. Instead, the paper is intended as a source of basic information regarding the terminology, practice and limitations of nuclear DNA estimation, especially by Feulgen microdensitometry, as currently practiced.

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The effects of monensin on transition cow metabolism may be dependent on modulation of feeding behavior, rumen pH, and expression of key metabolic genes. Multiparous Holstein cows were used to determine the effects of monensin (400mg/cow daily) on these variables. Cows were randomly assigned, based on calving date, to control or monensin treatments (n = 16 per treatment) 21 d before their expected calving date, and cows remained on treatments through 21 d postpartum. Feeding behavior and water intake data were collected daily. Liver biopsies were conducted after assessing BCS and BW on d -21, -7, 1, 7, and 21 relative to calving for analysis of triglyceride (TG) content as well as mRNA abundance of cytosolic phosphoenolpyruvate carboxykinase, carnitine palmitoyltransferase 1a, and apolipoprotein B. Blood samples were collected 21, 7, and 4 d before expected calving and 1 (day of calving), 4, 7, 14, and 21 d postpartum for nonesterified fatty acid, β-hydroxybutyrate, glucose, insulin, and haptoglobin analyses. Ruminal pH was collected every 5 min on d 1 through 6 postpartum via a wireless indwelling probe. On d 7 postpartum, a caffeine clearance test was performed to assess liver function. Data were analyzed using mixed models with repeated measures over time. Monensin decreased mean plasma β-hydroxybutyrate (734 vs. 616 ± 41 μM) and peak concentrations (1,076 vs. 777 ± 70 μM on d 4 postpartum). Monensin also decreased time between meals prepartum (143 vs. 126 ± 5.0 min) and postpartum (88.8 vs. 81.4 ± 2.9 min), which was likely related to a smaller ruminal pH standard deviation in the first day after cows changed to a lactation ration (0.31 vs. 0.26 ± 0.015). Monensin also increased liver mRNA abundance of carnitine palmitoyltransferase 1a (0.10 vs. 0.15 ± 0.002 arbitrary units), which corresponded to a slower rate of liver TG accumulation from d -7 to +7 (412 vs. 128 ± 83 mg of TG/g of protein over this time period). No significant effects of monensin supplementation were observed on milk production, liver cytosolic phosphoenolpyruvate carboxykinase, apolipoprotein B, plasma nonesterified fatty acid, glucose, insulin, or haptoglobin. No effects on disease incidence were detected, but sample size was small for detecting such effects. Overall, results confirm that the effects of monensin on transition cows extend beyond altered propionate flux.

Continuous delivery of factor VIII (FVIII) protein in hemophiliacs by gene therapy will represent a major clinical advance over the current practice of infrequent administration of purified FVIII. Conceptually, retroviral vectors that can permanently insert the FVIII gene into the DNA of the host cell appear the most suitable vehicles for this specific purpose. However, most retroviral vector systems have shown a poor performance in the production of FVIII from primary cells in vitro and in vivo. Here we report the retroviral-mediated gene delivery of a B-domain-deleted human FVIII by using the MFG vector system. This vector permitted efficient transduction of the majority of the primary cells in culture without the use of a selectable marker. High levels of FVIII were produced by various transduced primary cells in vitro. Upon transplantation of primary fibroblasts into mice, therapeutic levels of FVIII in the circulation were obtained for >1 weelk The capacity of primary cells to deliver the FVIII into the circulation was strongly dependent on the site of implantation. These results represent a major step forward in development of gene therapy for treating hemophilia A.

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