Apolipoprotein A-I metabolism in cholesteryl ester transfer protein transgenic mice. Insights into the mechanisms responsible for low plasma high density lipoprotein levels

Expression of simian cholesteryl ester transfer protein (CETP) in C57BL/6 mice causes the animals' high density lipoprotein (HDL) levels to decrease. The purpose of these studies was to determine how CETP expression caused that reduction. Chemical analysis showed that the HDL of the CETP transgenic mice had about twice as much triglyceride and only about 60% as much cholesteryl ester as the HDL from the C57BL/6 mice. Both strains of mouse had high levels of a circulating lipase. When plasma from the mice was incubated at 37 degrees C for 5 h, the triglycerides in the HDL were hydrolyzed, and apoA-I was shed from the particle. However, apoA-I was shed from the CETP HDL more rapidly than it was shed from the C57BL/6 HDL. Because "free" apoA-I is rapidly cleared by the kidney, increased production of free apoA-I would be expected to shorten the average life span of apoA-I in the mouse. Kinetic analyses indicated that the life span of apoA-I was significantly reduced in the CETP transgenic mice. It was concluded that CETP expression enriched the core of the HDL with triglyceride, which rendered it vulnerable to lipolysis, causing apoA-I to be shed from the particle. That shortened the life span of apoA-I in the CETP mice, which led to lower plasma levels of the protein.     

18-FDG imaging in breast cancer

A previously isolated parsley (Petroselinum crispum) cDNA with high sequence similarity to cinnamate 4-hydroxylase (C4H) cDNAs from several plant sources was expressed in yeast (Saccharomyces cerevisiae) containing a plant NADPH:cytochrome P450 oxidoreductase and verified as encoding a functional C4H (CYP73A10). Low genomic complexity and the occurrence of a single type of cDNA suggest the existence of only one C4H gene in parsley. The encoded mRNA and protein, in contrast to those of a functionally related NADPH:cytochrome P450 oxidoreductase, were strictly coregulated with phenylalanine ammonia-lyase mRNA and protein, respectively, as demonstrated by coinduction under various conditions and colocalization in situ in cross-sections from several different parsley tissues. These results support the hypothesis that the genes encoding the core reactions of phenylpropanoid metabolism form a tight regulatory unit.     

Performance improvement integration: a whole systems approach

Performance improvement integration in health care organizations is a challenge for health care leaders. Required for accreditation by the Joint Commission on Accreditation of Healthcare Organizations (Joint Commission), performance improvement (PI) can be designed as a sustainable model for performance to survive in a turbulent period. Central Baptist Hospital developed a model for PI that focused on strategy established by the leadership team, delineated responsibility through the organizational structure of shared governance, and accountability for outcomes evidenced through the organization's profitability. Such an approach integrated into the culture of the organization can produce positive financial margins, positive customer satisfaction, and commendations from the Joint Commission.     

Using the parallel process model to prevent firearm injury and death: field experiment results of a video-based intervention

This paper reports the outcome evaluation of a gun safety video intervention. Guided largely by the extended parallel process model, the video, Bullet 'Proof' - The Case for Gun Safety' focuses primarily on (a) knowledge of 6 gun safety practices, (b) susceptibility to accidental gunshot injuries and death, severity of gunshot injuries, (d) response efficacy, and (e) self-efficacy. The video was shown to 175 individuals in 7 hunter safety classes and evaluated in a field experiment using a posttest-only control-group design with random assignment. Compared to the control group, the experimental group listed significantly more gun safety practices, perceived greater susceptibility to accidental gun injuries, perceived gun injuries to be more severe, and perceived greater response efficacy toward some of the recommended gun safety practices. Further, all of the recommended gun safety practices received high self-efficacy and behavioral intention ratings. Finally, the video itself scored high on all measured positive attributes, and low on all measured negative attributes.     

Patterns of long-term steroidogenesis stimulation by ACTH and phorbol ester

Adrenocorticotropic hormone (ACTH) triggers well-defined responses in Y-1 cells. Among them is steroidogenesis stimulation. We have previously shown that phorbol 12-myristate 13-acetate (PMA), an activator of the calcium- and phospholipid-dependent protein kinase (PKC) is able to mimic all the responses triggered by ACTH in these cells, including steroidogenesis stimulation. Short (2 h) treatment with PMA leads to only 20-30% of the maximal steroidogenesis stimulation obtained with ACTH. However, the steroid secretion in the 2 h that follows the short-term (2 h) PMA treatment reaches the same levels as observed with ACTH, i.e., a 12- to 15-fold increase. We also show that this effect is restricted to cells treated with PMA for up to 4 h, while treatment for longer periods of time causes a reduction of the steroid biosynthesis rate, an effect that is not observed in cells treated with ACTH or N6,2'-0-dibutyryladenosine 3',5'-cyclic monophosphate (dcAMP). These results suggest that activation of PKC can elicit the first phase of ACTH steroidogenesis stimulation, but not the second one, which strictly depends on activation of cAMP-dependent protein kinase.     

Purification of Escherichia coli chromosomal segments without cloning

Pairs of genomic insertions made with elements carrying any one of several frequently used rare restriction sites allow physical purification of insertion delimited genes. However, native rare restriction sites can, either by causing (i) fragmentation of targeted intervals or (ii) generation of additional fragments that overlap electrophoretically with targeted ones, place severe limitations on this approach. We present a series of Escherichia coli mini-Tn10 insertions containing the rare-cutting polylinker 2 (RCP2) of rare restriction sites, which includes the 18-base-pair I-SceI site (absent from native E. coli sequences). Pulsed-field gel purification from RCP2 double insertion mutants of both an I-SceI fragment from strain K-12 (containing approximately 90-95 min) and an allelic I-SceI fragment from a pathogenic strain is demonstrated. The complete series of RCP2 insertions, containing different antibiotic resistances at intervals of approximately 35 kb in prototype K-12 strain MG1655, allows rapid purification of the genes from any E. coli chromosomal interval as an isolated I-SceI fragment.     

Significance of HPr in catabolite repression of alpha-amylase

CcpA and HPr are presently the only two proteins implicated in Bacillus subtilis global carbon source catabolite repression, and the ptsH1 mutation in the gene for the HPr protein was reported to relieve catabolite repression of several genes. However, alpha-amylase synthesis by B. subtilis SA003 containing the ptsH1 mutation was repressed by glucose. Our results suggest HPr(Ser-P) may be involved in but is not required for catabolite repression of alpha-amylase, indicating that HPr(Ser-P) is not the sole signaling molecule for CcpA-mediated catabolite repression in B. subtilis.     

The syndrome of primary aldosteronism: a case study

OBJECTIVE: Marked alterations occur in the synthesis of endometrium-specific proteins during the first third of pregnancy in the baboon. Because epidermal growth factor (EGF) expression has been associated with proliferation in the human and mouse endometrium, we hypothesized that EGF, transforming growth factor-alpha (TGF alpha), and EGF receptor (EGF-R) expression in baboon endometrium may be modulated by the early invasive trophoblast and play a role in decidualization of the endometrial stroma. METHODS: Endometrial tissue was obtained from cycling baboons (n = 4-5 per time point), ovariectomized steroid-treated baboons (n = 4 per group), or from pregnant baboons on days 18-60 of pregnancy (n = 2-4 per group). The tissue was fixed in Bouin's solution and embedded in paraffin for immunocytochemistry using polyclonal antibodies against EGF and EGF-R and a monoclonal antibody to TGF alpha. RESULTS: Endometrial staining was located almost entirely in the glandular epithelium for TGF alpha and EGF-R in the follicular phase animals, whereas EGF staining was strongest in the periglandular stroma. In the luteal phase, specific staining for EGF also was detected in the glands as well as the periglandular stroma. There appeared to be little difference in endometrial staining between the late follicular and mid-luteal phase for TGF alpha and EGF-R. A similar pattern was observed in the steroid-treated animals. In the endometrium from pregnant animals, EGF, TGF alpha, and EGF-R intensely stained the glandular epithelium on days 18, 25, and 32. Both EGF and EGF-R showed light stromal staining on days 18 and 25. Light stromal TGF alpha staining was present on day 25 and became moderately intense by day 32. By day 60, the most intense staining for EGF and EGF-R was stromal. Staining of TGF alpha continued to be strong in the remaining epithelium through day 60. In placenta, EGF and EGF-R intensely stained the syncytiotrophoblast, but not the cytotrophoblast, whereas TGF alpha stained only the villous cytotrophoblast and intermediate cytotrophoblast within maternal blood vessels. There appeared to be no change in this staining pattern or intensity in the placenta throughout early pregnancy. CONCLUSIONS: This study demonstrates the presence of EGF, TGF alpha, and EGF-R in the endometrium during the cycle and early pregnancy. The detection of EGF, TGF alpha, and EGF-R in the stromal cells during pregnancy correlated with the onset of decidualization. We propose that EGF, TGF alpha, and EGF-R may play a role in glandular development during the cycle and in decidualization and implantation during early pregnancy.