Relationship among cattle breed and anabolic implant protocol relative to feedlot performance: Growth, temperament, feeding behavior, carcass traits, and economic return

Recent research has suggested that different cattle breed types may respond differently to anabolic implant protocols of varying intensity. Therefore, the purpose of this research was to compare anabolic implant protocols in feedlot steers of 2 different breed types. Sixty steers were stratified by weight and breed in a 2 × 3 factorial design examining 2 different breeds: Angus (AN; n=38) or Santa Gertrudis influenced (SG; n=22), and 3 implant strategies: no implant (CON; n=20), a moderate intensity implant protocol (d0 implant: Revalor-G, d56 implant: Revalor-IS, d112 implant: Revalor-S; MI; n=20), or a high intensity implant protocol (d0 implant: Revalor-IS, d56 implant: Revalor-S, d112 implant: Revalor-200; HI; n=20). Steers were randomly placed into pens equipped with GrowSafe bunks to collect dry matter intake and feeding behavior. All animals were fed the same diet. Weight, chute score, exit velocity, serum, rectal temperature, hip height and 12th rib fat thickness were collected approximately every 28 d over a 196 d period. Serum urea nitrogen (SUN) was evaluated as well. Total average daily gain was increased (P < 0.0001) in both the HI and MI steers compared to the CON steers by 29.4% and 26%, respectively. A treatment × breed interaction was observed (P < 0.0001) for hip height, with AN-CON steers being shorter (P < 0.0007) than AN-HI, SG-CON, SG-MI, and SG-HI steers. A breed × treatment interaction was observed (P < 0.004) for chute score and rectal temperature, with SG-HI and SG-MI steers having increased chute scores (P < 0.001) when compared to AN-HI, AN-MI, AN-CON, and SG-CON throughout the course of the trial. Additionally, SG-HI and SG-MI steers had an increased rectal temperature (P < 0.004) compared to AN-HI, AN-MI, AN-CON, and SG-CON steers. A breed effect was observed (P = 0.002) for SUN with AN steers having increased (P = 0.002) SUN concentration compared to SG sired steers, in addition to a treatment effect (P < 0.0001), with CON steers having a higher (P < 0.0001) SUN concentration than MI and HI steers, regardless of breed. The MI implant protocol increased net return per head, on average, by $97.28, regardless of breed, while the HI implant protocol increased net return by only $80.84. Taken together, despite the cattle breed types responding differently to the different anabolic implant protocols at times, a moderate intensity anabolic implant protocol was optimal in this experiment for steers raised in a temperate climate.

A Multicenter Pilot Study on the Clinical Utility of Computational Modeling for Flow-Diverter Treatment Planning

BACKGROUND AND PURPOSE

Selection of the correct flow-diverter size is critical for cerebral aneurysm treatment success, but it remains challenging due to the interplay of device size, anatomy, and deployment. Current convention does not address these challenges well. The goals of this pilot study were to determine whether computational modeling improves flow-diverter sizing over current convention and to validate simulated deployments.

MATERIALS AND METHODS

Seven experienced neurosurgeons and interventional neuroradiologists used computational modeling to prospectively plan 19 clinical interventions. In each patient case, physicians simulated 2-4 flow-diverter sizes that were under consideration based on preprocedural imaging. In addition, physicians identified a preferred device size using the current convention. A questionnaire on the impact of computational modeling on the procedure was completed immediately after treatment. Rotational angiography image data were acquired after treatment and compared with flow-diverter simulations to validate the output of the software platform.

RESULTS

According to questionnaire responses, physicians found the simulations useful for treatment planning, and they increased their confidence in device selection in 94.7% of cases. After viewing the simulations results, physicians selected a device size that was different from the original conventionally planned device size in 63.2% of cases. The average absolute difference between clinical and simulated flow-diverter lengths was 2.1 mm. In 57% of cases, average simulated flow-diverter diameters were within the measurement uncertainty of clinical flow-diverter diameters.

CONCLUSIONS

Physicians found computational modeling to be an impactful and useful tool for flow-diverter treatment planning. Validation results showed good agreement between simulated and clinical flow-diverter diameters and lengths.

Recruitment, Representation, and Political Values

This article has two major objectives. First, it offers an examination of some important characteristics of the delegates to the 1976 Democratic National Convention, and comparisons are made with other recent conventions. Those 1976 delegate characteristics are also placed in the context of recent changes in the delegate selection rules. The second objective is to demonstrate empirically the extent to which the delegate selection rules and/ or the group characteristics of the delegates have a systematic impact on the dele gates' candidate preferences. In addition, several other more "political" variables are examined for their relationship to candidate fortunes. All of this analysis is ultimately addressed to the question of why Jimmy Carter was nominated and elected in 1976.

A Novel Eigenvector-based Method to Detect Mild Alzheimer's Disease Using Event-Related Potentials

Event-related potentials (ERPs) are a physiological measure of cognitive function that have shown diagnostic and prognostic utility in Alzheimer's disease (AD). In this study, we used a novel eigenvector-based technique to better understand brain electrophysiological differences between subjects with mild AD and healthy controls (HC). Using ERPs from 75 subjects with mild AD and 95 HC, we first calculated cognitive task eigenvectors within each subject from three conditions and then calculated second-order eigenvector components to compare the AD group to the HC group. A MANOVA of the three second-level components discriminated between AD and HC multivariately (Wilks' lambda=.4297, p<0.0001, R2 = .5703), and also on each of the three components univariately (all 3 p-values<0.0001). The eigenvector-based technique used in this study accurately discriminated between the mild AD group and HC. As such, this analysis method adds to our understanding of the differences in ERP signal between AD and HC, and could provide a sensitive biomarker for diagnosis and monitoring of AD progression.

Immuno-analysis of phospho-Akt in primary human breast cancers

The aim of this study was to investigate the expression of the activated (phosphorylated) form of Akt (Ser473) in primary breast cancer and to correlate the results with clinicopathological and prognostic variables for clinically relevant associations. Phospho-Akt expression was studied using immunoblot analysis in 49 invasive breast carcinomas (median follow-up time 55 months, range 7-74 months). We assessed the level of phospho-Akt in different types of primary breast cancers and compared the use of autoradiograph X-ray film with a PVDF-DAB-staining system. Twelve percent of the tumours had no phospho-Akt protein, 25% had low phospho-Akt expression, 51% had intermediate expression and 12% had high phospho-Akt expression. No relationship was observed between phospho-Akt and tumour grade, tumour size or nodal status. A significant relationship was demonstrated between phospho-Akt score and oestrogen receptor status (P=0.014). Univariate analysis demonstrated that intermediate levels of phospho-Akt in breast tumour tissue are associated with a lower probability of developing recurrences (P=0.035), while in multivariate analyses, none of the phospho-Akt levels appeared to be independent predictors of disease recurrence or death. In addition, it has been clearly established that a suitable composition of reagents and components such as PVDF membranes treated with DAB substrate will enable the performing of sensitive immuno-analyses.

Inhibition of compensatory renal growth by the N-terminus of a sheep-derived peptide

The N-terminal sequence of a novel sheep-derived peptide with growth inhibitory activity has been obtained. The N-terminal fragment was chemically synthesised and designated EPL001. The kidney was chosen as the first mammalian system in which to study EPL001 since kidney growth can be accurately quantified following a surgical reduction in renal mass. Cell proliferation was measured in mouse collecting duct kidney (MCDK) cells stimulated with insulin-like growth factor I (IGF-I). Compensatory renal growth (CRG) was induced in Wistar rats and either EPL001 or an EPL001 antibody delivered by continuous renal tissue infusion. Mouse monoclonal antibodies to EPL001 were generated for immunoneutralisation, rabbit polyclonal antibodies were generated for immunohistochemistry. EPL001 had no apparent effect on IGF-I stimulated cell proliferation in MCDK cells in vitro, yet provoked a dose-dependent inhibition of CRG in vivo. An EPL001 antibody potentiated CRG, in the absence of exogenous EPL001, consistent with an inhibitory role in kidney growth for an endogenous peptide containing the EPL001 sequence. Tubular staining for epitopes to the EPL001 sequence was detected in normal human kidney sections and enhanced in renal cell carcinoma. Results support the presence of growth inhibitory activity in the N-terminus of a sheep-derived peptide with evidence for both its presence and endogenous activity in the kidney. Attempts to further characterise its structure and activity are ongoing.

Atoms in a radio-frequency-dressed optical lattice

We load cold atoms into an optical lattice dramatically reshaped by radio-frequency coupling of state-dependent lattice potentials. This radio-frequency dressing changes the unit cell of the lattice at a subwavelength scale, such that its curvature and topology departs strongly from that of a simple sinusoidal lattice potential. Radio-frequency dressing has previously been performed at length scales from mm to tens of mum, but not at the single-optical-wavelength scale. At this length scale significant coupling between adiabatic potentials leads to nonadiabatic transitions, which we measure as a function of lattice depth and dressing amplitude. We also investigate the dressing by measuring changes in the momentum distribution of the dressed states.

Sublattice addressing and spin-dependent motion of atoms in a double-well lattice

We load atoms into every site of an optical lattice and selectively spin flip atoms in a sublattice consisting of every other site. These selected atoms are separated from their unselected neighbors by less than an optical wavelength. We also show spin-dependent transport, where atomic wave packets are coherently separated into adjacent sites according to their internal state. These tools should be useful for quantum information processing and quantum simulation of lattice models with neutral atoms.

Outpatient erythropoietin administered through a protocol-driven, pharmacist-managed program may produce significant patient and economic benefits

To assess the effect of a disease management program in anemia of chronic kidney disease (CKD), the authors reviewedthe records of all adults treated with epoetin alfa (EPO) at their institution between September 2003 and April 2006 and compared them with a group treated through a pharmacist-managed program with patients managed by PCPs in terms of time to target hemoglobin (Hb) (11-12.9 mg/dL), percent of Hb values maintained in target range, average weekly dose of EPO, and percent of iron-saturation (T-sat) values within target range (20%-50%) over a period of six months to one year. Although pharmacist-managed patients received lower weekly EPO doses than those managed by PCPs (6,698 vs. 12,000 units, respectively; P = .0001), they achieved goal Hb faster (47.5 vs. 62.5 days, P = .11) and maintained a higher percentage of Hb and T-sat values in target range (69.8% vs. 43.9%, P = .0001, and 64.8% (vs. 40.4%, respectively; P = .043). A pharmacist-managed program may present significant clinicaland economic benefits in anemia of CKD.

Preparing and probing atomic number states with an atom interferometer

We describe the controlled loading and measurement of number-squeezed states and Poisson states of atoms in individual sites of a double well optical lattice. These states are input to an atom interferometer that is realized by symmetrically splitting individual lattice sites into double wells, allowing atoms in individual sites to evolve independently. The two paths then interfere, creating a matter-wave double-slit diffraction pattern. The time evolution of the double-slit diffraction pattern is used to measure the number statistics of the input state. The flexibility of our double well lattice provides a means to detect the presence of empty lattice sites, an important and so far unmeasured factor in determining the purity of a Mott state.

Peritoneal macrophages express the serotonin transporter

Although it is known that macrophages take up serotonin, a specific monoamine transporter has not been identified in macrophages. In this study, mRNA coding for the serotonin transporter (SERT) was detected with the reverse transcription-polymerase chain reaction (RT-PCR) in recruited mouse peritoneal macrophages. Sequencing confirmed the identity of the RT-PCR product to mouse SERT mRNA. SERT protein was detected by Western blotting. Macrophage activation with lipopolysaccharide had no effect on expression of SERT mRNA or protein. Consistent with expression of a functional SERT, specific uptake of (3)H-serotonin in macrophages was sodium dependent and inhibited by fluoxetine (IC(50) 6.9 nM) and desipramine (IC(50) 32 nM) but not by nisoxetine or reserpine.

Apoptotic mechanisms in T47D and MCF-7 human breast cancer cells

To investigate the mechanisms underlying apoptosis in breast cancer cells, staurosporine was used as an apoptotic stimulus in the human breast cancer cell lines MCF-7 and T47D. Staurosporine induced dose and time dependent increases in DNA fragmentation which was abrogated by z-VAD-fmk. MCF-7 cells did not express caspase-3, suggesting that DNA fragmentation occurred in the absence of caspase-3 and that other caspases may be involved. Staurosporine induced DEVDase activity in T47D cells suggesting the involvement of caspase-3 and/or caspase-7, yet there was no DEVDase activity in MCF-7 cells, probably ruling out the involvement caspase-7. However, staurosporine induced the cleavage of pro-caspase-6 in MCF-7 cells, but not in T47D cells. Caspase dependent PARP cleavage was detected in MCF-7 cells at 3 h, whereas only partial PARP cleavage was detected in T47D cells and then only after 24 h. Moreover, staurosporine led to cytochrome c release at 2 h in MCF-7 cells and 6 h in T47D cells. In addition, a time dependent and caspase-independent reduction of the mitochondrial transmembrane potential was observed; which appeared to occur after the release of cytochrome c. Translocation of Bax from the cytosol to mitochondria was observed in both cell types, and this preceded cytochrome c release in both T47D and MCF-7 cells. Apoptotic events in both cell types differ temporally, involving activation of different caspases and mitochondrial changes.

Cloning of the cDNA for the putative calcium-sensing receptor and its tissue distribution in sea bream (Sparus aurata)

The cDNA for the calcium-sensing receptor (CaSR) gene has been cloned from the marine teleost Sparus aurata, the sea bream. The isolated clones were 3.3 kb long with an open reading frame of 2820 bp, a 5' UTR of 240 bp, and 3' UTR of 248 bp. The gene codes for a mature peptide of 940 amino acids which has three principal domains; the extracellular region is more than half the total protein, there is a seven-transmembrane domain, and there is a short intracellular domain. There is considerable sequence identity, 91%, shared between the CaSR of sea bream and puffer fish but overall similarities with mammalian CaSR peptides vary between 44% for rat and mouse and 48% with human CaSR. Nevertheless, the 18 cysteine residues of the extracellular domain are present in all sequences so far analysed of which 9 form a cysteine-rich region in sea bream similar to mammalian CaSR. The distribution of CaSR in sea bream tissues detected by in situ hybridisation showed gene expression in epithelia associated with ion transport or ion regulation including the hind gut, chloride cells of the gills, operculum, gall bladder, pituitary adenohypophysis, and coronet cells of the saccus vasculosus; this distribution was confirmed by RT-PCR. By in situ hybridisation, CaSR gene expression was also present in olfactory nerves and leucocytes.

STR primer concordance study

Over 1500 population database samples comprising African Americans, Caucasians, Hispanics, Native Americans, Chamorros and Filipinos were typed using the PowerPlex 16 and the Profiler Plus/COfiler kits. Except for the D8S1179 locus in Chamorros and Filipinos from Guam, there were eight examples in which a typing difference due to allele dropout was observed. At the D8S1179 locus in the population samples from Guam, there were 13 examples of allele dropout observed when using the Profiler Plus kit. The data support that the primers used in the PowerPlex 16, Profiler Plus, and COfiler kits are reliable for typing reference samples that are for use in CODIS. In addition, allele frequency databases have been established for the STR loci Penta D and Penta E. Both loci are highly polymorphic.

Interleukin-1 beta induced synthesis of protein kinase C-delta and protein kinase C-epsilon in EL4 thymoma cells: possible involvement of phosphatidylinositol 3-kinase

We present evidence here that the proinflammatory cytokine, interleukin-1 beta (IL-1 beta) stimulates a significant increase in protein kinase C (PKC)-epsilon and PKC-delta protein levels and increases PKC-epsilon, but not PKC-delta, transcripts in EL4 thymoma cells. Incubation of EL4 cells with IL-1 beta induced protein synthesis of PKC-epsilon (6-fold increase) by 7 h and had a biphasic effect on PKC-delta levels with peaks at 4 h (2-fold increase) and 24 h (4-fold increase). At the level of mRNA, PKC-epsilon, but not PKC-delta levels, were induced after incubation of EL4 cells with IL-1 beta. The signalling mechanisms utilized by IL-1 beta to induce the synthesis of these PKC isoforms were investigated. Two phosphatidylinositol (PI) 3-kinase-specific inhibitors, wortmannin and LY294002, inhibited IL-1 beta-induced synthesis of PKC-epsilon. However, the PI 3-kinase inhibitors had little effect on the IL-1 beta-induced synthesis of PKC-delta in these cells. Our results indicate that IL-1 beta induced both PKC-delta and PKC-epsilon expression over different time periods. Furthermore, our evidence suggests that IL-1 beta induction of PKC-epsilon, but not PKC-delta, may occur via the PI 3-kinase pathway.

The effects of inhalation exposure to bromo-dichloromethane on specific rat CYP isoenzymes

Several cytochrome P450 (CYP) isoenzymes may be involved in the metabolism of bromo-dichloromethane (BDCM), a drinking water disinfection byproduct. After 4-h inhalation exposures of male F344 rats to BDCM between 100 and 3200 p.p.m., hepatic microsomal methoxyresorufin demethylase (MROD), ethoxyresorufin de-ethylease (EROD) and pentoxyresorufin dealkylase (PROD) activities showed modest increases at low exposure levels and larger decreases at high exposure levels, compared with controls. Western blots for CYP1A2 and CYP2B1 showed similar trends. In addition, p-nitrophenol hydroxylase (PNP) activity was measured and Western blots for CYP2E1 were performed. CYP2E1 and CYP2B1 isoenzymes are known to metabolize BDCM (Thornton-Manning, J.R., Gao, P., Lilly, P.D., Pegram, R.A., 1993. Acute bromodichloromethane toxicity in rats pretreated with cytochrome P450 inducers and inhibitors. The Toxicologist 13: 361). When compared with a multiple gavage study of BDCM in female F344 rats (Thornton-Manning, J.R., et al., 1994. Toxicology 94, 3-18), the results of the two studies for EROD, PROD, and PNP activities were qualitatively the same; PNP activity did not change, while both PROD and EROD activities decreased at high exposures. In the current work, Western blots for CYP2E1, CYP2B1 and CYP1A2 supported the results from the PNP, PROD and MROD activities, respectively. The decreases in MROD and PROD activities and in Western blots for CYP1A2 and CYP2B1 at high exposures suggest that BDCM may be a suicide substrate for these CYP isoenzymes. Other important conclusions that can be drawn from the comparison between the current and prior work are that the liver response is similar for both sexes, and it is also similar for inhalation and gavage exposures under these conditions. Finally, the decrease in EROD activity at high doses, found in both studies, may be a further reflection of CYP1A2 activity, since little or no CYP1A1 activity is normally found in uninduced rat liver and CYP1A2 is known to metabolize ethoxyresorufin, although much more slowly than CYP1A1.

Possible role for protein kinase B in the anti-apoptotic effect of prolactin in rat Nb2 lymphoma cells

Prolactin (PRL) is a mitogen for a number of cell types and its action as a survival factor has recently been demonstrated in Nb2 lymphoma cells. However, the intracellular signalling pathways by which PRL promotes the survival of Nb2 cells is unknown. In previous studies, we have shown that PRL caused the activation of phosphatidylinositol 3-kinase (PI3-kinase) and its association with tyrosine phosphorylated fyn. Protein kinase B (PKB), a serine/threonine kinase, is now known to be a downstream component of the PI3-kinase pathway. The aim of the present study was to examine the effect of PRL on the activation of PKB and to find out whether this has any role on the PRL-induced survival of Nb2 cells. Our studies have revealed the phosphorylation and activation of PKB in PRL-stimulated Nb2 cells. We have also observed, using confocal microscopy, translocation of PKB to the membrane of Nb2 cells in response to PRL. These effects were blocked by the PI3-kinase inhibitor, LY294002 (10 microgram/ml). Apoptosis was induced by the general protein kinase inhibitor, staurosporine (STS; 0.1-1 microM), the synthetic glucocorticoid, dexamethasone (Dex; 100 nM) or ionising radiation by exposing Nb2 cells to X-irradiation (IR; 10 Gy). PRL had no effect on STS-induced apoptosis. On the other hand, PRL (100 ng/ml) inhibited apoptosis induced by Dex or IR; this effect of PRL was reversed by the addition of LY294002 (10 microgram/ml). Furthermore, Western blot analysis using phosphospecific PKB antibody on lysates from PRL-treated Nb2 cells showed that phosphorylation of PKB in response to PRL was inhibited by STS (0.5 microM), but not by Dex (100 nM). These results suggest that the PI3-kinase/PKB pathway may mediate the anti-apoptotic effect of PRL in Nb2 cells.

Cloning of the cDNA for sea bream (Sparus aurata) parathyroid hormone-related protein

This paper reports cloning of the cDNA for sea bream (Sparus aurata) parathyroid hormone-related protein (PTHrP). The gene codes for a 125-amino acid mature protein with a 35-residue prepeptide. The total gene sequence is 1.8 kb with approximately 75% noncoding. The N-terminus of the protein resembles mammalian and chicken PTHrP peptides with 12 of the first 21 amino acids identical and for which there is homology with mammalian parathyroid hormone. Toward the C-terminus, the nuclear transporter region between residues 79 and 93 in sea bream is 73% homologous to tetrapod PTHrP, and the RNA binding domain, 96-117, is 50% homologous, moreover starting with the conserved lysine and terminating with the lysine/arginine sequence. Sea bream PTHrP differs significantly from mammalian and chicken PTHrP, having a novel 16-amino acid segment between residues 38 and 54 and completely lacking the terminal domain associated in mammals with inhibition of bone matrix lysis. RT-PCR and in situ hybridization of sea bream tissues show that the gene is expressed widely and the results confirm observations of a PTHrP-like factor in sea bream detected with antisera to human PTHrP.

Caspase-3-like activity is necessary but not sufficient for daunorubicin-induced apoptosis in Jurkat human lymphoblastic leukemia cells

In the present study we have shown that the cancer therapeutic drug, daunorubicin, induces apoptosis in the human lymphoblastic leukemia cell line Jurkat E6.1. This effect was both dose-and time-dependent with nuclear fragmentation detectable by 8 h. Caspases have been implicated in pro-apoptotic events. By utilizing synthetic fluorochrome-linked substrates of the caspases, we observed that a caspase-3-like enzyme had dramatically increased activity (3340 130% with respect to basal levels) in response to daunorubicin treatment. Furthermore, by using an inhibitor to caspase-3, Ac-DEVD-CHO, we have shown that activation of a caspase-3-like enzyme appears to be necessary for nuclear fragmentation and apoptotic body formation, but is not required for chromatin condensation. In contrast, a general caspase inhibitor, Z-VAD-fmk, inhibited all apoptotic parameters measured. Ceramide has been implicated in daunorubicin-induced apoptosis in human myeloid leukemia cells. However, in Jurkat cells, caspase activation does not appear to be a consequence of ceramide generation since, although ceramide levels were elevated through the action of ceramide synthase in response to daunorubicin treatment, this occurred with slower kinetics than either nuclear fragmentation or caspase activation. In contrast, caspase inhibitors abrogated ceramide elevation induced by DNR treatment, suggesting that ceramide synthase may be a downstream target for caspase action. Therefore, daunorubicin-induced apoptosis does not appear to be mediated by ceramide in the lymphoblastic leukemia cell line, Jurkat E6.1. Instead, caspase 3 activity appears to be necessary, but not sufficient for this process.

The role of caspase 3 and BclxL in the action of interleukin 7 (IL-7): a survival factor in activated human T cells

The effects of interleukin 7 (IL-7) on apoptosis in interleukin 2 (IL-2)-dependent, activated, primary, human T lymphocytes (hT cells) was examined. IL-7 (like IL-2) rescued cells from apoptosis, as measured by their cellular DNA profile and fragmentation. IL-2 also acted as a mitogen in these T cells. Both cytokines abrogated the dexamethasone-induced stimulation of Caspase 3 and prevented the cleavage of poly (ADP-ribose) polymerase (PARP), a substrate for the Caspase 3. IL-7 upregulated the expression of Bc1xL and counteracted the downregulation of this anti-apoptotic protein by the synthetic glucocorticoid, dexamethasone. Bcl-2 protein expression was uupregulated by IL-7 with or without dexamethasone, but Bc1-2 was expressed at a much lower level than BclxL in these cells. Levels of Bax did not markedly change on either cytokine stimulation or dexamethasone treatment. An unidentified 23-kDa band, which was recognized by the anti-Bc1-2 antibody, was induced by dexamthasone and suppressed by IL-7 and IL-2. This protein was subject to independent regulation as compared to the p26 Bc1-2 protein, suggesting that it may be a novel factor, possibly involved in the regulation of apoptosis. A clear role for IL-7 as a survival factor for cytokine withdrawal and glucocorticoid induced apoptosis in activated primary hT cells is implicated. In addition, regulation of BclxL and downstream inhibition of Caspase 3 activity may mediate this rescue signal.

The start-stop procedure: estimation of temporal intervals by human subjects

In four experiments investigating human timing, subjects produced estimates of sample durations by bracketing their endpoints. On each trial, subjects reproduced a sample duration by pressing a button before the estimated sample duration elapsed (start time) and releasing it after the estimated duration elapsed (stop time). From these responses, middle time (start + stop/2) and spread time (stop - start) were calculated, representing the point of subjective equality and the difference limen, respectively. In all experiments, subjects produced middle times that varied directly with sample duration. In Experiment 2, middle times lengthened when feedback was withheld. Consistent with Weber timing, spread times, as well as the standard deviation of middle times, varied directly with middle time (Experiments 1, 3, and 4). On the basis of an internal clock model of timing (Gibbon & Church, 1990), the data permitted inferences regarding memory processes and response threshold. Correlations between start and stop times and between start and spread times agreed with earlier findings in animals suggesting that the variance of temporal estimates across trials is based in part upon the selection of a single temporal memory sample from a reference memory store and upon one or two threshold samples for initiating and terminating each estimate within a trial.

Prolactin induced tyrosine phosphorylation of p59fyn may mediate phosphatidylinositol 3-kinase activation in Nb2 cells

Our previous studies indicated that PI3-kinase is involved in prolactin (PRL) signalling. We have now examined the involvement of the src tyrosine kinase, fyn, in PRL-induced the activation of PI3-kinase in the rat lymphoma cell line, Nb2. Cells were stimulated with increasing doses of PRL, lysed and immunoprecipitated with anti-fyn specific antibody. Then PI3-kinase activity was measured as the increase in the phosphorylation of phosphatidylinositol to phosphatidylinositol 3-phosphate separated by TLC. Our data indicated that, in PRL treated cells, co-precipitation of PI3-kinase with anti-fyn antiserum led to time and dose-dependent activation of PI3-kinase in vitro and that this activation was blocked by the addition of LY294002. However, LY294002 appeared to have no effect on fyn autophosphorylation. Furthermore, the physical association of PI3-kinase with fyn was confirmed by Western blot analysis employing the same specific antisera. These data provide evidence that PRL-induced activation of PI3-kinase may be mediated by the tyrosine phosphorylation of fyn in Nb2 cells.

Interleukin-1beta-induced expression of protein kinase C (PKC)-delta and epsilon in NIH 3T3 cells

NIH 3T3 cells express the alpha, delta, epsilon and zeta isoenzymes of protein kinase C(PKC). Following stimulation of cells (24 h) with the pro-inflammatory cytokine, interleukin 1beta (IL-1beta), we observed, by Western blotting, a dose-dependent effect on the levels of PKC-epsilon and delta, but not on alpha or zeta. Moreover, time course analysis revealed that the isoenzymes, PKC-delta and epsilon were induced by IL-1beta after 7 h. Again, no change in PKC-alpha or zeta levels after IL-1beta treatment were detected. Incubation with selective PKC inhibitor peptides blocked the PKC-alpha, delta, epsilon and zeta antibodies binding to their respective isoenzyme bands. We also observed that the addition of the tumour-promoting phorbol ester, Phorbol 12-myristate 13-acetate (PMA), downregulated PKC-alpha, delta and epsilon by 7 h in NIH 3T3 cells. PMA did not affect constitutively produced PKC-zeta protein levels even after 24-h treatment. In summary, these results demonstrate that IL-1beta induces protein synthesis of the Ca2+-independent PKC-delta and epsilon isoforms in NIH 3T3 cells. The differences observed here between PKC isoenzymes in response to IL-1beta suggest that each isoenzyme may have a unique role in the signal transduction pathways of IL-1beta and that such isoenzyme may have a unique role in the signal transduction pathways of IL-1beta and that such selective expression may influence the action of agents which require PKC for signal transduction acting in concert with IL-1.

A 70-kDa protein facilitates interleukin-4 signal transduction in the absence of the common gamma receptor chain

Interleukin-4 signal transduction (and activation of STAT 6) is known to be mediated via its binding to a p140 receptor chain and the common gamma chain (gamma c). In non-activated monocytes, neither the gamma c nor its associated signal transducing molecule, Jak3, is expressed. We nevertheless show that IL-4 can initiate the tyrosine phosphorylation and DNA binding of STAT 6 in these cells. We present evidence for an additional 70 kDa IL-4 receptor chain which mediates the tyrosine phosphorylation of STAT 6 via Jak2, and suggest that this is the means by which IL-4 can signal in cells lacking the gamma c.

Methanol potentiation of carbon tetrachloride hepatotoxicity: the central role of cytochrome P450

Evidence to explain the enhanced hepatotoxicity of carbon tetrachloride (CCl4) following methanol exposure by inhalation is presented. Hepatic microsomes prepared from male F344 rats exposed to methanol at concentrations up to 10,000 ppm showed increased p-nitrophenol hydroxylase activity but no increase in pentoxyresorufin-O-dealkylase or ethoxyresorufin-O-deethylase activities. Hepatic antioxidant levels, glutathione levels and glutathione-S-transferase activity in methanol-treated animals were not different from controls. In vitro metabolism of CCl4 was also increased in microsomes from methanol-treated animals. Pretreatment with allyl sulfone, a specific chemical inhibitor of cytochrome P450 2E1, abolished the difference in microsomal metabolism between exposed and control animals. This study shows that methanol exposure induces cytochrome P450 2E1, which appears to be the principal toxicokinetic mechanism responsible for the increased metabolism and thus the increased hepatotoxicity of CCl4.

Activation of phosphatidylinositol 3-kinase by prolactin in Nb2 cells

In the present studies, using anti-phosphotyrosine (PY20) and PI3-kinase (p85) antibodies, we have shown that PRL causes activation of phosphatidyl inositol 3-kinase (PI3-kinase) in vitro in a dose- and time-dependent manner in Nb2 cells. PRL activated PI3-kinase was completely inhibited by LY294002 (1 microgram/ml). Stimulation of the cells with PRL also increased tyrosine phosphorylation of the 85-kDa regulatory subunit. Moreover, in vitro kinase assay followed by SDS-PAGE protein separation demonstrated the phosphorylation of several other proteins besides the p85. However, no direct association between p85 and JAK2 tyrosine kinase was observed. These results indicate, for the first time, the involvement of PI3-kinase in PRL-stimulated Nb2 cell growth.

Fasting for less than 24 h induces cytochrome P450 2E1 and 2B1/2 activities in rats

Cytochrome P450 (CYP) 2E1 activity is induced after 24 h of fasting but no information is available for shorter fasting periods. We investigate the induction of CYP 2E1, 2B1/2 and 1A1 in young adult male F344 rats after 8, 16 and 24 h of fasting compared to control. Liver microsomes were analyzed for the following enzyme activities: p-nitrophenol hydroxylase (PNP) for CYP 2E1, pentoxyresorufin-O-dealkylase (PROD) for CYP 2B1/2 and ethoxyresorufin-O-deethylase (EROD) for CYP 1A1. After each fasting interval, the activities per mg microsomal protein for PNP and PROD increased but the activity of EROD remained unchanged. Western blots for CYP 2E1 and CYP 2B1 showed increases comparable to the PNP and PROD activities, respectively. On a whole organ basis, increases were found for PNP and PROD activities, while decreases were found for EROD activity and total microsomal protein. The results are consistent with an induction of CYP 2E1 and CYP 2B1/2 activities after as little as 8 h of fasting.

Interleukin-1 beta induces the synthesis of adenylyl cyclase in Swiss 3T3 fibroblasts and MG-63 osteosarcoma cells

In this study, the longer term (> or = 6 hours) effect of interleukin-1 beta on adenylyl cyclase activity was investigated in Swiss 3T3 and MG-63 cells. No change was evident after 6 hours but after 1, 7 or 15 day incubations a significant increase in basal (1.5- 2 fold) and NaF-stimulated (2-4 fold) adenylyl cyclase activity was observed in interleukin-1 beta pre-treated cell membranes compared with non pre-treated controls. The response to forskolin, a direct stimulus of adenylyl cyclase, was also significantly enhanced, indicating that the effect of interleukin-1 beta was targeted to the enzyme itself. This action of interleukin-1 beta was blocked by co-incubation with cycloheximide, an inhibitor of protein synthesis, which demonstrated that de novo protein synthesis was required. It is concluded that interleukin-1 induces the expression of adenylyl cyclase in 3T3 and MG-63 cells, leading to enhanced activation by NaF and forskolin.

Adjunctive treatment of cranial base malignacies

The indications for skull base tumor surgery have increased in recent years primarily because of improving surgical techniques and adjunctive treatment modalities. In this article we review current and future adjunctive treatment for cranial base malignancies. Surgically clear tumor margins are often difficult to achieve in skull base surgery because of unacceptable morbidity to surrounding structures. Current phase I and II trials of adjunctive radiation and chemotherapy are discussed. Future advances in radiation therapy and chemotherapy are introduced.

The mitogenic action of recombinant basic FGF in Swiss 3T3 cells is independent of early diradylglycerol production and downregulatable protein kinase C activity

In this study we have investigated the requirement for phosphoinositide metabolism, diradylglycerol (DG) production and protein kinase C (PKC) activation in recombinant basic fibroblast growth factor (rbFGF)-mediated reinitiation of DNA synthesis in Swiss 3T3 cells. We have assessed the involvement of PKC activation in rbFGF-induced DNA synthesis by two approaches; enzymic inhibition by H7 and down-regulation by prolonged phorbol-ester treatment. In both conditions we observed that rbFGF was able to sustain a significant component of its mitogenic response, therefore denying an exclusive role for the activation of downregulatable and H7-sensitive PKC isoforms in rbFGF-induced reinitiation of DNA synthesis. Moreover, we have found no evidence for diacylglycerol accumulation in response to rbFGF by 3T3 cells. In previous studies, we observed that rbFGF caused a moderate and slow accumulation of total inositol phosphates. This effect was significant only after a 60 min incubation. It is our contention that rbFGF, in our culture system, does not exert a direct effect on phosphoinositide metabolism.

Fractured clavicle in the neonate: a retrospective three-year review

A hospital-based case-controlled study was undertaken to determine maternal and neonatal characteristics associated with fractured clavicle. A total of 11,604 consecutive vaginal deliveries of liveborn infants in vertex presentation at the Mount Sinai Hospital from 1988 to 1990 were reviewed. Maternal and neonatal characteristics were compared for the neonates with and without a diagnosis of a fractured clavicle. Compared to controls, mothers of neonates with a fractured clavicle were more likely to be nulliparas or primiparas, to have had an operative vaginal delivery, and to have been delivered by an attending as opposed to a resident physician. The fractured clavicle group also had a longer gestational age, greater birthweight, and higher frequency of macrosomic infants. After controlling for maternal parity, type of delivery and infant birthweight, experience of the delivering physician, and gestational age at delivery were not significantly different. Fracture of the clavicle in the neonate is related to maternal parity, mode of delivery, and infant birthweight but not to the level of experience of the delivering physician.

Evaluation of Hinf I-generated VNTR profile frequencies determined using various ethnic databases

Concerns have been raised about hypothetical problems arising from the use of statistics for determining the likelihood of occurrence of DNA profiles for forensic purposes. A major contention is that reference databases based on subgroups of a major population category rather than on general (or major) population groups, might yield large differences in the estimated likelihood of occurrence of DNA profiles. This hypothetical issue is based on the assertion by some people that the differences among subgroups within a race would be greater than between races (at least for forensic purposes). To evaluate the effects of the above concern the likelihood of occurrence of 615 Hinf I-generated target DNA profiles was estimated using fixed bin frequencies from various ethnic databases and the multiplication rule. Based on the data in this study, differences in allele frequencies at a particular locus do not have substantial effects on VNTR profile frequency estimates when subgroup reference databases from within a major population group are compared. In contrast, the greatest variation in statistical estimates occurs across-major population groups. Therefore, the assertion, by some critics that the differences among subgroups within a race would be greater than between races (at least for forensic purposes), is unfounded. The data in the study support that comparisons across major population groups provide valid estimates of DNA profile frequencies without forensically significant consequences. The data do not support the need for alternate procedures, such as the ceiling principle approach, for deriving statistical estimates of DNA profile frequencies.

Internal clock and memory processes in animal timing

Temporal control of behavior was investigated within the framework of an internal clock model. Pigeons were exposed to signaled fixed-interval 30-s trials mixed with extended unreinforced (baseline) trials. On unreinforced break trials, the signal was interrupted for a period of time after trial onset. In Experiment 1, comparisons between the peak time obtained on baseline and on break trials produced peak time shifts that were longer than those expected if the clock had stopped during the break but shorter than if the clock had reset. In Experiment 2, systematic manipulations of duration and location of breaks produced peak time shifts that were nonlinear functions of break duration and that varied linearly with break location. The obtained peak times were more consistent with a continuous memory decay model than with the stop-retain or the reset hypotheses.

Internal clock and memory processes in animal timing

Temporal control of behavior was investigated within the framework of an internal clock model. Pigeons were exposed to signaled fixed-interval 30-s trials mixed with extended unreinforced (baseline) trials. On unreinforced break trials, the signal was interrupted for a period of time after trial onset. In Experiment 1, comparisons between the peak time obtained on baseline and on break trials produced peak time shifts that were longer than those expected if the clock had stopped during the break but shorter than if the clock had reset. In Experiment 2, systematic manipulations of duration and location of breaks produced peak time shifts that were nonlinear functions of break duration and that varied linearly with break location. The obtained peak times were more consistent with a continuous memory decay model than with the stop-retain or the reset hypotheses.

The assessment of frequency estimates of Hae III-generated VNTR profiles in various reference databases

The likelihood of occurrence of 1964 Hae III-generated target DNA profiles was estimated using fixed bin frequencies from various regional and ethnic databases and the multiplication rule. The databases generally were from the following major categories: Black, Caucasian, Hispanic, Oriental, and American Indian. It was found that subdivision, either by ethnic group or by U.S. geographic region, within a major population group did not substantially affect forensic estimates of the likelihood of occurrence of a DNA profile. As expected, the greatest variation in estimates for within-group estimates was among American Indian databases. Because the greatest variation in statistical estimates occurs across-major population groups, in most cases, there will be no unfair bias applying general population database estimates. Therefore, based on empirical data, there is no demonstrable need for using alternate approaches, such as the ceiling approach, to derive statistical estimates. The current practice of using general population databases and the multiplication rule provides valid estimates of the likelihood of occurrence of a DNA profile.

Stimulation of arachidonic-acid release from Swiss 3T3 cells by recombinant basic fibroblast growth factor: independence from phosphoinositide turnover

In this study we have attempted to characterize the mechanism of recombinant bovine basic fibroblast growth factor (rbFGF)-induced release of arachidonic acid from prelabelled Swiss 3T3 fibroblasts. Recombinant bFGF caused the release of [3H]arachidonic acid from metabolically labelled cells in a dose- and time-dependent manner. This effect was maximal with 10 ng rbFGF/ml and became significant after a 30-min incubation. Although rbFGF was able to cause a modest increase in total inositol phosphate accumulation, an examination of the time-course of the latter effect revealed that enhanced [3H]arachidonic-acid release could not have been derived from phosphoinositide metabolism. Evidence suggesting that rbFGF-induced release of [3H]arachidonic acid was being mediated via a PLA2 pathway was obtained by pharmacological antagonism using mepacrine, a putative PLA2 inhibitor. Moreover, treatment of cells with neomycin failed to attenuate rbFGF-mediated release of [3H]arachidonic acid. Chelation of extracellular calcium by EGTA was found to abrogate rbFGF-induced liberation of [3H]arachidonic add. Down-regulation of protein kinase C (PKC) by prolonged treatment of cells with the phorbol ester, PMA, was observed to have no effect on the action of rbFGF on [3H]arachidonic add release from Swiss 3T3 fibroblasts. While rbFGF was found to cause the indomethacin-sensitive production of prostaglandin E2 (PGE2) in a dose-dependent manner, this effect was independent of rbFGF-induced reinitiation of DNA synthesis. Clearly, the effect of rbFGF on cellular DNA synthesis was being mediated independently of PGE2 biosynthesis. We discuss the potential importance of the PLA2-signalling pathway in the mechanism of action of fibroblast growth factors.

Advanced abdominal pregnancy complicated by bilateral ureteral obstruction. A case report

A case of term abdominal pregnancy is reported. The patient was followed throughout pregnancy, but the diagnosis was made only at the time of laparotomy for elective cesarean section. The report exemplifies the ease with which the diagnosis of abdominal pregnancy can be overlooked and stresses the importance of considering this diagnosis in cases of high maternal serum alpha-fetoprotein. The management of the placenta is also discussed. In this case the retained placenta was managed successfully without intervention despite the unusual complication of bilateral ureteral obstruction. Additionally, the biochemical activity of the placenta was assessed by following the progressive decline of serum human chorionic gonadotropin over time.

A system for documentation of pharmacist interventions with incorporation into performance and quality improvement plans

Budgetary constraints have compelled hospital administrators to take a more discerning look at the role of the pharmacist within the healthcare team. In 1991, financial difficulties and hospital-wide cutbacks at Northern Michigan Hospital resulted in the loss of pharmacy personnel. Consequently, the department has increasingly found it necessary to document the clinical activities of the pharmacists and their potential effect on patient care. To document therapeutic interventions, two forms specific to this activity were developed. These forms allowed evaluation of both the quantity and quality of interventions. The authors realize it is essential for pharmacists to not only maintain, but to continually update their knowledge base to be prepared for the future. A staff development program was developed to help meet the educational needs of the pharmacists. This article describes how therapeutic interventions were integrated into the quality improvement and performance plans to help motivate staff to continually improve their pharmacy practice skills at this institution.

Double-blind; placebo-controlled trial of piperacillin prophylaxis in preterm membrane rupture

OBJECTIVE

We attempted to test whether antibiotic therapy prolongs pregnancy in preterm premature rupture of membranes, because preterm premature rupture of membranes is frequently associated with chorionic-decidual infection.

STUDY DESIGN

Women with preterm premature rupture of membranes and a singleton gestation at 24 to 34 completed weeks were randomized to receive either piperacillin 3 gm or placebo intravenously every 6 hours for 72 hours and were managed conservatively until spontaneous delivery, chorioamnionitis, or fetal distress.

RESULTS

Between January 1987 and January 1992, a total of 75 patients were randomized to receive piperacillin (n = 38) or placebo (n = 37). There were no differences between the piperacillin group and the placebo group in mean gestational age at randomization (30.2 +/- 3 vs 30.3 +/- 2.9 weeks). However, a greater number of patients had pregnancy prolonged beyond 7 days (42.1% vs 10.8% p = 0.005) and the mean latency period was significantly prolonged (11.4 +/- 18.8 vs 6.1 +/- 13.6 days, p = 0.001) in the piperacillin group compared with the control groups.

CONCLUSIONS

Use of intravenous piperacillin for 72 hours in preterm premature rupture of membranes significantly prolongs the latency period between membrane rupture and delivery.

Bradykinin stimulates the production of prostaglandin E2 and interleukin-6 in human osteoblast-like cells

The effect of bradykinin (BK) on proteinase activity, prostaglandin synthesis, and the production of interleukin-6 (IL-6) was investigated in cultures of human osteoblast-like cells. Bradykinin had no effect on stromelysin activity and plasminogen activator activity produced by human osteoblast-like cells. However, BK stimulated the production of prostaglandin E2, an effect that was markedly enhanced by pre-incubation with recombinant interleukin-1 alpha (rhIL-1 alpha), but was apparently unaffected by BK receptor antagonists types 1 and 2. Bradykinin stimulated the intracellular accumulation of total inositol phosphates suggesting that its effects were mediated by stimulation of phosphoinositide metabolism. Bradykinin within the dose range of 10(-11)-10(-5) M also significantly stimulated the production of IL-6. Bradykinin may, therefore, mediate a variety of responses in bone under both physiological and pathological conditions.

Behavioral contrast: Pavlovian effects and anticipatory contrast

Two sources of behavioral contrast have been identified previously: Pavlovian stimulus-reinforcer relations and component sequence effects (anticipatory contrast). This study sought to isolate these sources of control procedurally in a four-ply multiple schedule composed of two fixed two-component sequences. Different cues were associated with the first component of each sequence, and contrast effects were studied in these target components. In Experiment 1, differential cuing of Component 2 between sequences and availability of reinforcement during target components were varied across three groups of pigeons; the stimulus-reinforcer relation between target-component cues and schedule of reinforcement in Component 2 was varied within subjects. Control by the Pavlovian relation was demonstrated under all conditions, and anticipatory contrast was not observed. In Experiment 2, target-component duration was systematically varied in the three groups of Experiment 1. Control by the Pavlovian relation was reliably obtained only when target-component behavior was unreinforced, and diminished with increases in component duration. Anticipatory contrast emerged in the two groups for which target-component reinforcement was available. These and other data indicate that Pavlovian effects in multiple schedules may be obscured when the requisite conditions for anticipatory contrast are present.

Maxillary removal and reinsertion for improved access to anterior cranial base tumors

Portions or all of the maxillae are oftentimes removed solely to provide access to certain cranial base tumors rather than because they are involved directly with disease. The purpose of this report is to describe an approach that involves removal of one or both maxillae to improve tumor exposure with subsequent reinsertion as free bone grafts which are stabilized with titanium craniofacial fixation plates. The titanium permits postoperative imaging studies and radiotherapy. Eleven patients ranging from 10 to 69 years of age have undergone 12 operations using this technique for resection of 4 benign and 8 malignant tumors at The Ohio State University. Seven of the 8 patients with malignancies underwent postoperative radiation therapy. There have been no permanent complications and no evidence of bone resorption in this group after follow-up of up to 15 months.

The regulation of connective tissue metabolism by vasoactive intestinal polypeptide

Immunohistochemical studies have confirmed the innervation of bone with neuropeptidergic neurons containing vasoactive intestinal polypeptide (VIP), substance P (SP) and calcitonin gene-related peptide (CGRP). In this study, we report effects of VIP on connective tissue cell metabolism. VIP stimulated PGE2 production in human articular chondrocytes, human osteoblast-like cells and human synovial cells, however, stromelysin production was unaffected. VIP also stimulated cAMP production in human osteoblast-like cells, but not in human articular chondrocytes or synovial cells. These findings are suggestive of a role of VIP in connective tissue cell metabolism which may contribute to the inflammatory processes of arthritis.