Search

New IMI of cows milked with high and low slip rate milking machine liners were compared. High slip liners used in this study averaged 6.1 initial slips and 7.6 major vacuum fluctuations per cow milking, and low slip liners averaged 3.6 initial slips and 3.1 major vacuum fluctuations per cow milking. Least squares means for new IMI rates per 100 cow days were .49 in the high slip group and .27 in the low slip group. Rates of clinical cases per 100 cow days were .35 in the high slip group and .20 in the low slip group. New IMI rates for cows entering the trial with an existing infection were .81 in the high slip group and .39 in the low slip group. More new IMI tended to occur with cows milked with the high slip liners than with low slip liners.

Triiodothyronine (T3) induces the transcription of the human chorionic somatomammotropin (hCS) promoter transfected into rat pituitary (GC) cells, but does not stimulate the homologous human growth hormone (hGH) promoter. As demonstrated by forward and reverse mutagenesis, this differential T3 responsiveness is due to subtle structural differences in a T3 response element located between nucleotides -64 and -44 of the 5'-flanking DNA of the hGH and hCS promoters. Synthetic hCS(-70/-40) DNA binds thyroid hormone receptors with a 4-fold higher affinity than the corresponding hGH T3 response element, indicating that small differences in receptor binding properties are reflected by major differences in T3 responsiveness. Analysis of circular permutation fragments containing the native hGH and hCS or mutated hCS(-70/-40) sequences demonstrates that the thyroid hormone receptor induces DNA bending. The extent of bending shows a possible correlation with the function of these sequences, suggesting that the receptor-induced changes in DNA conformation may be required for thyroid hormone receptor action.

Longitudinal observations made during the past two decades on the prevalence of chronic ear disease in Inuit Elementary School Children in the Eastern Canadian Arctic reveal that as the current segment of this population enters into the 1990's a significant decrease in the prevalence is occurring. While we can speculate ad infinitum why this is happening we really do not know the answer. The usual cliché is adaptation to contact, improved medical/social services, housing, diet, etc.

A radial basis function approximation has the form s ( x ) = is some given function, ( y j ) n 1 are real coefficients, and the centres ( x j ) n 1 are points in ℝ d . For a wide class of functions φ, it is known that the interpolation matrix is invertible (see [5]). Further, several recent papers have provided upper bounds on ‖ A −1 ‖ 2 , where the points ( x j ) n 1 satisfy the condition ‖ x j – x k ‖ 2 ≥ δ, j ≠ k , for some positive constant 6. In this paper, we show that the generalized Fourier transform of φ provides a simple and elegant tool for the derivation of such estimates.

A recent study demonstrated that the incidence of new arrhythmias occurring during central venous catheter insertion or exchange was 41% atrial and 25% ventricular arrhythmias (12% couplets or greater). Over-insertion of the guidewire, causing direct stimulation to the right side of the heart, has been postulated to be the causative factor. A new technique that allows the operator to control the length of guidewire inserted was developed. With this technique on a population of hospitalized patients, similar to those in the previous study, the incidence of atrial arrhythmias decreased to 32% and the incidence of ventricular arrhythmias to 6% (single premature ventricular contractions only). Although this new technique has limitations, there was a dramatic improvement in the incidence of cardiac arrhythmias. These results indicate a need for modifications in the available equipment to avoid the infrequent but life-threatening complication of malignant arrhythmia.

Prorenin, the inactive biosynthetic precursor of renin, is proteolytically cleaved in the renal juxtaglomerular cells to renin. The activity of renin is rate-limiting for generation of angiotensin II in the circulation. We identified a renal thiol protease which activates and accurately cleaves the 43-amino acid prosegment of human recombinant prorenin. In the current studies, 6.5 mg of this protease was purified from human renal cortex using a three-step procedure dependent upon Leu-Leu-arginyl affinity chromatography. This represented an overall 766-fold purification and resulted in three protein bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis of molecular weights 30,000, 25,000, and 24,000. All three bands cross-reacted with an anti-human liver cathepsin B antibody upon immunoblot analysis; electrolution of each band and amino-terminal sequence analysis confirmed that the Mr 30,000 protein was mature cathepsin B and the Mr 25,000 and 24,000 bands were cathepsin B subunits. The pH optimum for the hydrolysis of pure human recombinant prorenin by pure renal cathepsin B was 6, and the Michaelis-Menten constant, Km, of the reaction was 1.4 x 10(-9) M. Immunostaining of human kidney using a sheep anti-human cathepsin B antibody demonstrated the presence of cathepsin B in the juxtaglomerular areas of the kidney, as well as in the renal proximal tubules. Electron microscopic immunohistochemistry using the same antibody demonstrated cathepsin B in dense secretory granules of the juxtaglomerular cells. Renin was also shown to be present in these granules. This study provides both biochemical and morphological evidence that renal cathepsin B is a human prorenin-processing enzyme.

Structural and functional changes of the gastric mucosa were studied in rats made portal hypertensive by partially ligating the portal vein. Studies were carried out at either 3 or 12 days after ligation or sham operation. At 3 days, structural changes were greater than at 12 days, the major effects being vascular congestion in the lamina propria, muscularis mucosa, submucosa, and submucosal oedema. Transmission electron microscopy showed only a mild hyperplasia in the muscularis mucosa. Gastric blood flow appeared to decrease at 3 days post-ligation compared to sham-operated control rats, but was significantly increased by 12 days after ligation (P less than 0.01). Cardiac output also appeared to increase in the portal hypertensive rats by 12 days post-ligation but this was not statistically significant. Portal venous inflow was significantly increased by 12 days (P less than 0.05) but after correction for collateral circulation liver blood flow had returned to normal values by 12 days post-ligation.

The rationing of medical care prioritizes the need for early predictors of death in the surgical intensive care unit (SICU). We prospectively studied 100 consecutive SICU admissions, looking for predictors of early death in the SICU and the cost implications of these findings. Serial APACHE II scores on days 1, 3, and 5 were subjected to multinomial logistic regression analysis to determine significant predictors of death in the SICU on day 1. Survivors had significantly lower (p less than 0.05) mean day-1 APACHE II scores than had nonsurvivors (13.6 vs 22.1). Half of the patients with scores greater than 18 died, and all patients with scores on day 1 of 25 or greater died. Significant predictors of death on SICU day 1 were APACHE II scores, Acute Physiology Score, Glasgow Coma Score, creatinine level, and Chronic Health Evaluation Score. Forty-one patients had been transferred from community hospitals as a results of acute illness; this population accounted for two thirds of the deaths in the SICU. Ten of 18 nonsurvivors were predicted on day 1, with these patients incurring a total cost of approximately $1 million. If therapy had been modified on days 5, 10, or 15, the potential cost savings would have been $340,000, $240,000, or $140,000, respectively. Integration of the results of this study into the management decision-making process and treatment guidelines may reduce the cost of care in the SICU.

The regulation by tumor necrosis factor alpha (TNF) of its own promoter has been investigated by transient transfection and nuclear protein binding assays. In human K652 erythroleukemia cells TNF produced an 8-10-fold activation of the human TNF promoter linked to the chloramphenicol acetyltransferase gene. The TNF-responsive element was localized to the -125 to -82 region by examining the TNF activation in 5'-deletion or site-directed mutants of the TNF promoter and by demonstrating that the -125 to -82 fragment confers TNF responsiveness to the thymidine kinase promoter. This region contains a palindrome, 5' TGAGCTCA 3', that resembles the consensus binding sequences for the transcription factors, activator protein-1 (AP-1), cyclic AMP-responsive element binding protein (CREB), and activation transcription factor (ATF). An internal deletion in the palindrome abolished the TNF responsiveness, whereas known AP-1 and CREB/ATF elements were unresponsive to TNF. In band shift analyses a nuclear factor from U937 cells specifically bound to the -125 to -82 TNF-responsive fragment in or near the palindromic sequence. Oligonucleotides containing AP-1 or CREB/ATF sites did not effectively compete for the binding, indicating that the U937 cell factor is different from these factors. Anti-c-fos antiserum did not affect binding of the U937 cell factor, whereas anti-c-jun antiserum did block its binding, indicating that either c-jun or a protein antigenically related to c-jun is a component of the factor. These results suggest that the TNF-responsive element is not activated by AP-1 or CREB in U937 cells and that a novel DNA binding factor is important for constitutive and inducible TNF gene expression.

A complete external events probabilistic risk assessment has been performed for the N-Reactor power plant, making full use of all insights gained during the past ten years' developments in risk assessment methodologies. A detailed screening analysis was performed which showed that all external events had negligible contribution to core damage frequency except fires, seismic events, and external flooding. A limited scope analysis of the external flooding risk indicated that it is not a major risk contributor. Detailed analyses of the fire and seismic risks resulted in total (mean) core damage frequencies of 1.96E-5 and 4.60E-05 per reactor year, respectively. Detailed uncertainty analyses were performed for both fire and seismic risks. These results show that the core damage frequency profile for these events is comparable to that found for existing commercial power plants if proposed fixes are completed as part of the restart program. 108 refs., 85 figs., 80 tabs.

Pregnancy and development are known to modify carcinogenesis. Little is known about the mechanism for the modulation. These studies investigated the relative sensitivity of nonpregnant, pregnant, and fetal mice to the induction of covalent DNA modifications and micronucleated erythrocytes by 4-nitroquinoline 1-oxide (4-NQO). Our results revealed that 4-NQO was bound to guanine nucleotides of DNA in all maternal and fetal organs tested. The adduct levels ranged from 2-60 base modifications per 10(9) DNA bases when 4-NQO was administered s.c. Overall, 4-NQO bound preferentially to DNA of the maternal tissues compared with that of the corresponding fetal tissues, with the exception of the liver. The adduct levels in maternal and fetal organs fell into 3 distinct levels. The greatest binding was in maternal lungs and pancreas (the target organs for carcinogenesis). The lowest binding levels were in maternal liver and all fetal organs studied. Gestation age at the time of 4-NQO treatment did not produce a significant effect on the amounts of adduct formation in the tissues examined, with the exception of placenta and bone marrow. Chronic treatment did not affect binding preference. At the cellular level, 4-NQO treatment induced twice the frequency of micronucleated erythrocytes in the bone marrow of pregnant mice compared with the nonpregnant mice and fetal liver, on a mg/kg basis. However, the polychromatic erythrocytes of fetal liver were more sensitive than those of adult bone marrow to the induction of micronuclei, when adduct levels were taken into account. A positive correlation of organotropsim between 4-NQO-induced DNA adducts and carcinogenicity was observed for maternal tissues, but not for fetal tissues. Fetal tissues, overall, lack the enzymes to metabolically activate 4-NQO. Fetal cells elicit greater biological responses, compared with adult cells, at equal adduct levels. This study reveals that the effective doses in maternal and fetal tissues may differ and, therefore, will be a better basis for further understanding the molecular mechanism of transplacental carcinogenesis.

In this article we describe experiments in which ultra-thin films of polyimide were formed on polycrystalline and (111) single crystal copper substrates following heating of a vapor deposited layer of polyamic acid produced by codeposition of 4,4'-diaminodiphenyl ether (ODA) and 1,2,4,5- benzenetetracarboxylic dianhydride (PMDA). The adsorption of the pure components and their subsequent polymerization was followed, in situ, with X-ray photoelectron spectroscopy. Molecular adsorption of the monomers was studied to determine their thermal stability. The composition and adhesion of the thin polyimide film is influenced by fragmentation of precursors at the interface. Keywords: Adhesion, Vapor deposition, Polyimide films, X-ray photoelectron spectroscopy.

The induction of transplacental carcinogenesis by 3-methylcholanthrene (MC) in mice is determined, in part, by the genotype at the Ah locus. The relationship of Ah genotype and MC-induced DNA adducts was tested by comparing the response of pregnant and fetal C57BL/6 mice (Ahb Ahb; responsive to the induction of MC metabolism) and DBA/2mice (Ahd Ahd; nonresponsive). On day 17 of gestation (day 1 = presence of vaginal plug), C57BL/6 mice were treated i.p. with 100 mg/kg MC and DBA/2 mice with 30 mg/kg. Mice were sacrificed 24 h later and the tissues were analyzed for the presence of DNA adducts using the P1 nuclease version of the 32P-postlabeling method. With a 3.3-fold difference in administered dose, the total adduct levels in fetal DNA were (a) similar in both strains with the exception of liver, for which C57BL/6 mice had more adducts; (b) higher in the lung than skin, liver, or thymus; and (c) only 1/4 to 1/14 of the adult levels. Maternal DBA/2DNA contained more adducts in the thoracic lymph nodes and liver but fewer in the placenta and lung, compared to maternal C57BL/6 DNA. More adducts were detected in lung DNA than liver DNA in C57BL/6 mice. In contrast, these levels were similar in DBA/2 mice. When the difference in dose administered was considered in conjunction with this, less MC bound to DNA of C57BL/6 than DBA/2 mice overall. To identify adducts, oxidized metabolites of MC, 1-hydroxy-, 2-hydroxy-, 9,10-dihydrodiol-, or 3-methoxymethyl-MC, were topically applied to the dorsal skin of both strains. All of these metabolites produced adducts. Approximately 14 different adduct spots were detected. The two most abundant adducts were produced by 1-hydroxy-, 2-hydroxy-, and 9,10-dihydrodiol-MC. One of these also contained a 3-hydroxymethyl group. Several adducts did not contain the 9,10-dihydroxy group. The adducts derived from 3-methoxymethyl-MC were consistently found in greater abundance in DNA from C57BL/6 tissues, compared with DBA/2. Thus, oxidation of the 3-methyl group may be enhanced by Ah-dependent induction of MC metabolism. Together, these results suggest that the individual and total adduct levels are influenced by the genotype at the Ah locus, the route of administration, and the metabolite(s) with tissue and age specificity.

As of April 1987, states were permitted to raise the speed limit on rural interstates to 65 mph without incurring federal sanctions; 38 states elected to do so in 1987. Fatality data for the months when the new limit was in effect in 1987 were compared with fatalities in the same months of 1982-86 on rural interstates and other rural roads. Fatalities on rural interstates in the states with increased speed limits in 1987 were conservatively estimated to be 15 percent higher than they would have been if the states had retained the 55 mph limit (95% CI = 6, 24). Among states that retained the 55 mph limit, fatalities on rural interstates were 6 percent lower than expected (95% CI = -23, 13).

This is a case study of the conception and development of an Expert System, for use at point-of-sale, to advise on the appropriate "consumables" for a customer's welding task.

During normal defaecation the intrarectal pressure increases but, in the absence of a reference catheter in the pelvis, the contribution of abdominal straining and rectal contraction to this rise is unclear. Anorectal manometry was performed in ten consecutive women with no gastrointestinal symptoms in an attempt to measure intrapelvic pressure using a catheter in the bladder. During filling the mean(s.e.m.) rectal pressure increased from 2(1) to 18(4) cmH2O. The mean(s.e.m.) intravesical pressure remained unchanged at 2(1) cmH2O. Evacuation of the rectal balloon produced an increase in mean(s.e.m.) intrarectal pressure from 18(4) (end-filling pressure) to 68(15) cmH2O. The mean(s.e.m.) intravesical pressure increased from 2(1) to 51(18) cmH2O. The true intrarectal pressure (intrarectal minus intravesical) did not rise during defaecation. The rise in intrarectal pressure during rectal evacuation occurs by increased intrapelvic pressure alone.

We report a 58-year-old man with recurrent ulceration in a Barrett's oesophagus whose iron-deficiency anaemia was in fact due to a caecal carcinoma. Recent reports suggest an association between these two disorders. A Barrett's oesophagus should not be blamed for iron deficiency unless neoplasms of the colon have been excluded.

Applied Surgical Anatomy – A Guide for the Surgical Trainee M. A. Glasby, W. J. Owen and F. Kristmundsdottir (eds) 252 × 192 mm. Pp. 299. Illustrated. 1998. Oxford: Butterworth-Heinemann. £49.50. A Guide to Laparoscopic Surgery A. Najmaldin and P. Guillou 233 × 154 mm. Pp. 169. Illustrated. 1998. Oxford: Blackwell Science. £24.95.

UNLABELLED: The purpose of the study was to compare the ease of insertion of the laryngeal mask airway using the standard uninflated approach or with a fully inflated cuff. Two hundred consecutive patients undergoing anesthesia using a laryngeal mask airway were randomized to have the laryngeal mask inserted using either method. Successful insertion was judged primarily by the clinical function of the airway. The number of insertion attempts to achieve a satisfactory airway and whether an alternative technique was required for success were recorded. On removal of the laryngeal mask, a blind observer noted the presence or absence of blood. Just before leaving the recovery room, each patient was asked whether they had a sore throat. Insertion technique made no difference with regard to first attempt success. However, the presence of blood on the removed masks (P < 0.01) and sore throat (P < 0.01) were less frequent in the inflated cuff group. We conclude that the inflated cuff insertion technique is an acceptable alternative to the standard approach and has the advantage of reducing the incidence of minor pharyngeal mucosal trauma, as evidenced by mucosal bleeding and sore throat. IMPLICATIONS: Insertion of the laryngeal mask airway with the cuff fully inflated is equally successful to the standard uninflated approach in experienced hands. The inflated technique was associated with less minor pharyngeal mucosal trauma and, consequently, a lower incidence of postoperative sore throat. This implies that the inflated technique would be acceptable to the general population of laryngeal mask users.

Thyroid hormone-responsive tissues contain chromatin "receptor" proteins that are concentrated in chromatin subfractions enriched in DNA. These receptors appear to be DNA-binding proteins. In the present study, we utilized a DNA-cellulose binding assay to further examine the interactions of solubilized receptors with DNA. [125I]Triiodothyronine associates with receptors bound to DNA-cellulose, whereas free [I]triiodothyronine and [125I]triiodothyronine associated with other proteins does not. The DNA-receptor interactions appear to be strong enough to exist at physiological ionic strength since binding is 50% maximal ag 0.175 M NaCl and is only partly inhibited by Ca2+ and Mg2+ in the 1 to 5 mM range. Most, if not all, of the receptors are capable of DNA binding, and there are at least 80,000 receptor binding sites/diploid DNA (assuming one triiodothyronine binding site/receptor). Binding of the receptor-[125I]triiodothyronine complexes to other DNAs and analogs was examined using a competition assay. There is similar binding by native and denatured DNA, gy eukaryotic DNA from different species and by prokaryotic DNA (Bacillus subtilis). Binding by natural DNAs is more avid than by cytoplasmic RNA, nuclear RNA, poly(dA-dT)-poly(dA-dT), or poly(dG-dC)-poly(dG-dC). Under these conditions, binding by tRNA and poly(dA) is insignificant, and the nucleotide monomers ATP and GTP have no detectable binding. These studies support the idea that the thyroid hormone receptor is a DNA-binding protein and that the interaction is a major determinant for receptor localization in chromatin. The competition studies suggest that the polynucleotide composition and/or conformation can have marked influences on the binding, and that multiple orders of binding affinity can exist. The presence of specific sequences cannot be excluded. However, the finding that receptors bind extensively and tightly to DNA suggests that receptors in chromatin may randomly bind to any available DNA, resulting in some of the receptors being at physiologically unimportant sites. If so, the several thousand hormone receptors present in each target cell may be required to enhance the possibility that some of the receptors are present at the actual sites of action.

A diet containing 11.5% (dry matter basis) of a moderately high Cd sewage sludge was fed to six Hereford steers for 106 days to simulate a high sludge intake from sludge-amended soils. At a mean live weight of 460 kg, the steers were slaughtered and liver, kidney, bone, muscle, lung, brain and spleen tissues were collected for heavy metal determinations; tissues were also collected at this time from six control steers fed the same diet with no sludge. The sludge-fed cattle consumed an average of 8.95 kg of diet dry matter/day and gained 1.13 kg/day. This feed intake was slightly higher, but the gain lower than that of control cattle. All gains were equal to those expected from intake of non-sludge diet components. This indicated that the sludge had approximately zero energy value and was acting as a dietary diluent. The sludge metal content (ppm, dry basis) was: Cd, 98; Hg, 18; Pb, 466; Cu, 1,733, and Zn, 1,733. Addition of sludge increased metal contents of the feedlot diet to 30 to 100 times that of the control. Retention of heavy metals in the total animal from sludge ingestion averaged .09%, .06% and .3% for Cd, Hg and Pb; no retention was noted from Cu and Zn. These low fractional retentions increased tissue Cd, Hg and Pb concentrations of liver and kidney tissues by five to 20-fold. Estimates of levels that would enter the human diet from average beef tissue consumption if all feedlot steers were fed sludge are presented for Cd, Hg and Pb. The data indicate that cattle are a moderately effective screen against the entry of these potentially toxic metals into the human diet.

Was there a secret revolutionary movement in England during the early Industrial Revolution and, if there was such a movement, must we accept that its existence would be “unprovable”? Should we agree with a recent writer that no conclusions can be reached on such questions, the existing historical sources being so ambiguous as to allow the historian to impress his own prejudices on them?. We believe that a rigorous study of the historical evidence of a revolutionary tradition in one region can offer an insight into this important area of English social history. The purpose of this essay will be to set the revolutionary aspect of Sheffield's political history against a brief outline of the town's economic development.