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The strength and conditioning and rehabilitation sectors use the deadlift as an integral part of their programming (Escamilla et al., 2000). Furthermore, what shoes to wear while deadlifting is a r...

The elastase I gene enhancer that specifies high levels of pancreatic transcription comprises three functional elements (A, B, and C). When assayed individually in transgenic mice, homomultimers of A are acinar cell specific, those of B are islet specific, and those of C are inactive. To determine how the elements interact in the elastase I enhancer and to investigate further the role of the C element, we have examined the activity of the three possible combinations of synthetic double elements in transgenic animals. Combining the A and B elements reconstitutes the exocrine plus endocrine specificity of the intact enhancer with an increased activity in acinar cells compared with that in the A homomultimer. The B element therefore plays a dual role: in islet cells it is capable of activating transcription, whereas in acinar cells it is inactive alone but greatly augments the activity specified by the A element. The C element augments the activity of either the A or B element without affecting their pancreatic cell type specificity. The roles of each element were verified by examining the effects of mutational inactivation of each element within the context of the elastase I enhancer. These results demonstrated that when tested in animals, the individual enhancer elements can perform discrete, separable functions that combine additively for cell type specificity and cooperatively for the overall strength of a multielement stage- and site-specific transcriptional enhancer.

The elastase I (EI) gene is expressed at high levels in the exocrine pancreas and at lower levels in other regions of the gut. The transcriptional enhancer of the EI gene, from nucleotides -205 to -72, recapitulates the expression of the endogenous gene in transgenic mice; it directs not only pancreatic acinar cell expression of a human growth hormone (hGH) transgene but also expression to the stomach, duodenum, and colon. This pattern of selective expression limited to the gastroenteropancreatic organ system is specified by the A element, one of three functional elements in the EI enhancer. When multimerized, the A element directed expression of a hGH reporter gene selectively to the pancreas, stomach, and intestine in transgenic mice. Immunofluorescent localization of hGH indicated that the A element multimer transgenes were expressed in the acinar cells of the pancreas as well as in Brunner's gland cells of the duodenum. The A element binds a pancreatic acinar cell-specific factor, PTF1. Our results show that while the A element is responsible for directing tissue and cell type specificity, other elements of the enhancer must be involved in the regulation of the level of gene expression.

The generic two lamp F40 rapid start lamp-ballast system has been improved for operation with the 35-W low energy lamp type. Substantial improvements in the lamp phosphor composition and in the ballast design and construction have contributed to the overall gains in system performance.

The intact chicken transferrin gene was microinjected into fertilized mouse eggs, and the resulting transgenic animals were used to produce lines of mice containing integrated copies of the chicken gene. The levels of expression of the chicken gene were quantitated in various tissues, and the response of the gene to estrogen stimulation was measured after chronic or acute estrogen exposure. Two of the three mouse lines studied maintained stable levels of expression in successive generations of offspring, and the third line had two- to threefold-higher levels in offspring than in the original parent. In the third line, the original transgenic parent was found to be a mosaic. The chicken transferrin gene was expressed at 10- to 20-fold-higher levels in liver than in any other tissue; however, the levels of chicken transferrin mRNA in kidney were higher than expected, indicating that the tissue specificity was only partial. In all three lines, the foreign gene was induced by estrogen administration. After 10 days of estrogen administration, there was a twofold increase in both transferrin mRNA and transcription of the chicken transferrin gene. A single injection of estradiol led to a fourfold increase in transferrin mRNA synthesis at 4h. As a control the levels of mouse albumin were measured, and both the level of albumin mRNA and its rate of transcription declined about twofold after estrogen administration. Our results indicate that the intact chicken gene with 2.2 kilobases of 5' flanking sequence contains signals for both tissue specificity and steroid regulation that can be recognized in mice.

(1984). Fluorescent Lamp Operating Characteristics at High Frequency. Journal of the Illuminating Engineering Society: Vol. 14, 1984 IES Annual Conference papers, pp. 211-224.

There has been increasing interest among lamp and ballast manufacturers for a testing procedure to determine the peak and rms starting volt relationships for fluorescent lamps. This paper discusses a preferred starting volt procedure along with typical test results for single and multilamp rapid start circuits. These peak/rms relationships are shown as a function of starting aid distance, fill gas pressure and composition, cathode heat, and starting capacitor size for various F40 lamp types.

The mouse alpha-fetoprotein gene is activated in embryonic development in the visceral endoderm of the extraembryonic yolk sac and the fetal liver and gut. Transcription of the gene is subsequently repressed in the neonatal liver. To ask whether the DNA sequence elements required for tissue-specific activation are the same or different from those required for postnatal developmental regulation of the gene, modified copies of the alpha-fetoprotein gene were microinjected into fertilized mouse eggs. Those animals which developed to term and carried integrated copies of the modified gene were analyzed for expression. In approximately 50% of such animals, the introduced gene was active only in the three cell lineages which expressed the authentic alpha-fetoprotein gene. Furthermore, its expression was repressed in the neonatal liver. Thus, we conclude that the modified genes, which included either 7 or 14 kilobase pairs of 5'-flanking DNA, contained the DNA sequence information to direct both tissue-specific expression and developmental regulation. The observation that 50% of the mice which carried the modified gene did not express it in any tissue, combined with the fact that the level of expression was highly variable between expressing transgenic animals, suggested that the gene was susceptible to its site of integration in the mouse genome.

Starting voltage values have been measured with F40-type, rapid-start fluorescent lamps operating at 60 Hertz as well as at various high frequencies. The test circuits used as well as their suggested procedures are discussed along with the resultant data.

Internal conductive coatings are an essential part of predominantly krypton filled, rapid start fluorescent lamps. Calculations on the maximum value of the end-to-end coating resistance for given axial distributions and starting voltage requirements are presented by the authors.

Recent domestic and international developments with smaller diameter fluorescent lamps have prompted a review of lamp and system performance as a function of tube diameter. Limiting constraints on system performance when lamps of various diameter are used with the standard rapid start ballast are discussed. Performance comparisons are also made when these various diameter lamps are mated with ballasts optimized specifically for both 60 HZ and high frequency operation. The role of lumen maintenance in affecting the mean footcandle level throughout the lamp life is a key issue in these discussions.

An elastase-human growth hormone (hGH) fusion gene containing 205 base pairs of elastase 5' flanking region is expressed exclusively in pancreatic acinar cells of transgenic mice. This paper shows that the promoter region (-72 to +8) and the enhancer (-205 to -73) function independently of each other. The elastase enhancer can activate the heterologous mouse metallothionein gene and the hGH gene promoters; conversely, enhancers from the thymocyte-specific murine leukemia virus MCF13 and the metal regulatory elements from the metallothionein gene can activate the elastase promoter in a variety of cell types. Combinations of immunoglobulin and elastase enhancers with a heterologous promoter and the hGH gene result in expression in all of the tissues predicted by the sum of each enhancer acting alone. Thus these enhancer elements act independently of each other, suggesting that they do not have silencing activity in cells in which they are normally inactive.