Abnormalities of circulating immunoreactive pancreatic anionic trypsinogen in cystic fibrosis: an assay artifact due to cross-reacting serum antibodies

In patients with CF, serum pancreatic cationic trypsinogen has proven to be useful for newborn diagnostic screening and also as a test of pancreatic function in the older patient. However, an assay for serum anionic trypsinogen is of no value as a test of pancreatic function in CF due to an apparent artifactual elevation of this enzyme in some patients. In this study, we evaluated the extent of the abnormality in the anionic trypsinogen assay and also elucidated the nature of the interfering material. CF patients were grouped according to the presence (pancreatic insufficiency) or absence (pancreatic sufficiency) of steatorrhea. In CF infants, both serum cationic and anionic trypsinogen levels were greatly elevated. Serum cationic trypsinogen declined with age in patients with pancreatic insufficiency, reaching low or undetectable levels after 6 years. In contrast, serum anionic trypsinogen levels remained normal or elevated in 33% of those over 6 years of age. There was no age-related change in either cationic or anionic trypsinogen among the CF patients with pancreatic sufficiency, and the majority had normal or elevated levels. Serum samples from selected CF patients were separated into IgG and non-IgG fractions using Staph. Protein A columns. Immunoreactive cationic and anionic trypsinogen were detectable in the non-IgG fractions of sera from CF infants and older patients with pancreatic sufficiency. In older CF patients with undetectable serum cationic and anionic trypsinogen, no immunoreactive material was detectable in either the IgG or non-IgG fractions.(ABSTRACT TRUNCATED AT 250 WORDS)

Use of an IgA-depleted intravenous immunoglobulin in a patient with an anti-IgA antibody

In this report we describe the use of an IgA-depleted preparation of intravenous gamma-globulin in a patient with hypogammaglobulinemia and an anti-IgA antibody. An IgA containing intravenous gamma-globulin had previously produced anaphylactoid reactions, immune complex formation, and complement activation. The patient has had no reactions to the IgA-depleted preparation after 18 months of treatment; immune complex formation and complement activation have not been demonstrated, and the titer of antibody to IgA has diminished.

Reduced triglyceride formation from long-chain polyenoic fatty acids in rat hepatocytes

The mechanism for the marked reduction in hepatic triglyceride secretion when rats are fed fish oils was explored in studies with isolated rat hepatocytes. Hepatocytes obtained from Sprague-Dawley rats fed either chow or fish oil or safflower oil were incubated in the presence of [3H]-glycerol to estimate triglyceride formation. In some experiments, various fatty acids, complexed to albumin, were added to the incubations. Similar experiments were carried out with hepatocytes from a genetic strain of hypertriglyceridemic, obese rats. In the absence of added fatty acid, hepatocytes from fish oil-fed rats produced and secreted substantially less triglyceride than cells from safflower oil-fed rats. However, the addition of 2 mmol/L Na oleate stimulated triglyceride formation similarly in both types of hepatocytes. When hepatocytes from chow fed rats were incubated with fatty acids of increasing chain length and unsaturation (oleate, linolenate, arachidonate, eicosapentaenoate, and docosahexaenoate), the latter two, which characterize the fish oil used, almost totally suppressed triglyceride formation. Coincubation with oleate partly reversed this effect. Hepatocytes from the hypertriglyceridemic rats synthesized significantly more triglyceride than hepatocytes from normal rats; however triglyceride formation was markedly reduced also in this strain of rat by feeding fish oil or by adding docosahexaenoate to hepatocytes in vitro. These studies confirm previous conclusions with perfused livers from fish oil-fed rats that showed diminished triglyceride production and secretion. These findings suggest that diversion of polyenoic acids from pathways of esterification is a major factor in the triglyceride lowering effect of fish oils.(ABSTRACT TRUNCATED AT 250 WORDS)

Bentiromide test for assessing pancreatic dysfunction using analysis of para-aminobenzoic acid in plasma and urine. Studies in cystic fibrosis and Shwachman's syndrome

We evaluated the bentiromide test by analyzing para-aminobenzoic acid (PABA) in plasma and urine (a) for the identification of patients with complete pancreatic insufficiency and (b) as an alternative to the secretin-cholecystokinin test. Nine control subjects, 18 patients with cystic fibrosis, and 4 patients with Shwachman's syndrome were studied. Based upon the secretin-cholecystokinin test, pancreatic function was judged to be less than 0.1% of normal in 7 patients with cystic fibrosis and malabsorption and between 0.7% and 90% of control values in 11 patients with cystic fibrosis and 4 patients with Shwachman's syndrome without malabsorption. The bentiromide test was performed in two stages: first with bentiromide alone, then with equimolar free PABA. After ingestion of free PABA, the plasma profile and urinary excretion of PABA were comparable in controls, patients with cystic fibrosis, and patients with Shwachman's syndrome. Thirty minutes after oral bentiromide, plasma PABA values in patients with and without malabsorption were significantly lower than in the control group. From 60 to 180 min after ingestion, plasma PABA levels in patients without malabsorption were no different from controls; whereas levels in patients with malabsorption were significantly lower than in controls and in those without malabsorption, reaching the highest significance at 90 min. Similar results were obtained when the urinary excretion of PABA was considered. Only the 90-min plasma test reliably detected cystic fibrosis patients with steatorrhea, however. Duodenal colipase output was highly correlated with both the 90-min plasma test and the urinary excretion of PABA, with similar results for lipase and trypsin output. Reliable detection of pancreatic dysfunction, nevertheless, was not obtained even with the plasma test, in cystic fibrosis patients with greater than 5%-10% of the mean normal enzyme output. In patients with Shwachman's syndrome, none of whom had malabsorption, the plasma and urinary test failed to detect pancreatic dysfunction even with enzyme output as low as 1% of normal.

Lactation suppression. Nonpharmaceutical versus pharmaceutical method

Mothers bottle feeding their infants need an adequate method of lactation suppression to prevent/lessen discomfort related to breast engorgement. This study compared the effectiveness of a non- pharmaceutical method (ice and tight bra) of suppressing lactation to a pharmaceutical therapy (bromocriptine mesylate). The sample consisted of 36 subjects who used the pharmaceutical therapy (drug group) and 17 subjects who used the non-pharmaceutical method (protocol group). The data showed that the drug group had significantly less engorgement, milk production, and discomfort on the fourth postpartum day, but the lactation process was prolonged until postpartum day nine or 16. The protocol group had more engorgement, milk leakage, and discomfort on postpartum day four, but the lactation process was completed before postpartum day 16.

The role of fibreoptic bronchoscopy in the management of respiratory burns

We found that fibreoptic bronchoscopy was a useful, simple, safe and accurate method in the diagnosis of inhalation injury, determining the type, the site and the extent of damage sustained. The most common mucosal damage was erythema and oedema of the supraglottic and glottic tissues, though in a few cases more severe and extensive injury was seen. Death seemed to be determined largely by the extent of skin burn but since there did not appear to be a close relationship between the severity of skin burn and the presence of inhalation burn, we suggest that the two types of injuries be evaluated separately. The main therapeutic role lies in the assessment and anticipation of imminent upper airway obstruction caused by oedema of the supraglottic tissues and the glottis. Endotracheal intubation could then be carried out promptly. Changes in clinical features and laboratory results were too slow to be of use in the prediction of upper airway obstruction, but could be indirect indicators of lower and peripheral airway injury.

Factors affecting the rate of hydrolysis of starch in legumes

In an attempt to understand the mechanism for the extremely slow rate of digestion and absorption of carbohydrate from legumes, we have examined a number of factors which could potentially affect the process in vitro. The rate of hydrolysis of legume starch in vitro was not affected by the presence of fat (as either butter or an emulsion). However, it was significantly increased in commercially available canned bean preparations, suggesting that the high temperatures used in the canning process may alter the availability of starch in legumes. In vitro starch hydrolysis rate was also significantly increased by grinding legumes finely prior to cooking. Finally, the slow rate of digestion and absorption of legume carbohydrate does not appear to be due to viscosity since a) increasing the shaking rate of viscous mixture of either red kidney beans or lentils from 0 to 120 oscillations per minute did not affect the hydrolysis rate, and b) a thick viscous mixture of either of these legumes did not retard the diffusion of free glucose from a dialysis sac into the dialysate.

Insulin inhibits the cholera-toxin-catalysed ribosylation of a Mr-25000 protein in rat liver plasma membranes

A method is described for preparing a plasma-membrane fraction from hepatocytes by a rapid, gentle, Percoll fractionation procedure. Cholera toxin elicited the ribosylation of a number of proteins in these membranes, including the components of the stimulatory guanine nucleotide regulatory protein, Ns. Insulin, however, inhibited the ability of cholera toxin to ribosylate a protein of Mr 25 000. The action was decreased in membranes from cells that had been pre-treated with glucagon. Ribosylation of both the components of Ns and the Mr-25 000 species occurred in whole cells treated with cholera toxin, because membranes from such treated cells exhibited decreased labelling when incubated with [32P]NAD+ and activated cholera toxin. The labelling of proteins, including the Mr-25 000 species, with [32P]NAD+ and cholera toxin in the plasma membranes was decreased by an inhibitor of ribosylation. Azido-GTP photoaffinity labelling identified several high-affinity GTP-binding proteins, including one of Mr 25 000. Cholera toxin failed to ribosylate the Mr-25 000 protein in membranes from cells that had been pre-treated with the tumour-promoting agent 12-O-tetradecanoylphorbol 13-acetate (TPA). In membranes from such treated cells, insulin actually allowed cholera toxin to label this species. As TPA activates protein kinase C, it is possible that the Mr-25 000 protein, or a species that interacts with it, is a substrate for phosphorylation. These observations may offer an explanation for some of the perturbing effects that TPA exerts on insulin's action. It is suggested that the insulin receptor interacts with the guanine nucleotide regulatory protein system in the liver, and that the Mr-25 000 species may be a component of Nin, a specific guanine nucleotide regulatory protein that has been proposed to mediate certain of the actions of insulin on target cells [Houslay & Heyworth (1983) Trends Biochem. Sci. 8, 449-452].

Student unrest: a challenge for nurse educators

Nursing students, like their college counterparts, are beginning to revolt against hierarchical authority and to claim a more active part in their educational planning. Nurse educators can no longer assume that their students will never revolt; they must face up to the challenge of developing strategies for proper management of student unrest. The authors propose some ways to deal with the complex issue of student unrest. These suggestions are made with emphasis on faculty-student relationship and the curriculum. Improved faculty-student relationships, proper utilization of student peer influence and student involvement in curriculum planning are some of the strategies proposed in this paper.

Apgar scores and cerebrospinal fluid beta-endorphinlike immunoreactivity during the first day of life. Preliminary observations

beta-Endorphinlike Immunoreactivity (BLI) was measured in sterile, bloodless samples of cerebrospinal fluid (CSF) during the first 24 hours of life in order to assess the relationship between perinatal asphyxia and endogenous opioid activity within the central nervous system. The median CSF BLI in infants with one-minute Apgar scores of 1 to 4 was 148 pg/mL (range, 96 to 171 pg/mL) and that of infants with Apgar scores of 5 to 9 was 78 pg/mL (range, 25 to 162 pg/mL). The linear regression equation correlating CSF BLI with one-minute Apgar score was y = -10.7x + 169.1. Our findings of a highly significant inverse correlation between one-minute Apgar scores and CSF BLI support the hypothesis that perinatal asphyxia is associated with increased activity of opioid systems in the central nervous system.

A randomized controlled trial of a new approach to preoperative teaching and patient compliance

A randomized controlled experiment evaluating the effects of a new approach to preoperative teaching on patient compliance is described. In this study, compliance was measured by the accuracy, regularity and willingness that patients showed in execution of the prescribed activities after surgery. A significant difference was found between the experimental and control patients in the regularity, willingness and accuracy with which they performed the prescribed postoperative exercises. The experimental patients were significantly more satisfied with this approach to preoperative teaching than the control patients. This study is seen to have implications for both nursing education and nursing service.

An in vivo study of corneal surface morphologic features in patients with keratoconjunctivitis sicca

We used wide-field color specular microscopy to study the corneal epithelium of 13 normal subjects and 13 patients with keratoconjunctivitis sicca. The frequencies of small, medium, and large cells were different in the two groups, with a shift to small cells in patients with keratoconjunctivitis sicca. Increased uptake of rose bengal dye, filaments, coarse mucus plaques, and pre-exfoliative sheets were also found in the patients with keratoconjunctivitis sicca. These findings suggest accelerated epithelial cell loss from the surface of the eye in keratoconjunctivitis sicca.

Color specular microscopy of disorders involving the corneal epithelium

Color specular microscopy, a noninvasive, in vivo microscopic technique, was utilized to study the corneal epithelium in 17 patients including eight with keratoconus, seven with bullous keratopathy, and two with Fuchs' corneal dystrophy. Color specular microscopy was also performed on rabbit corneas with experimental surgical trauma. Changes observed by specular microscopy in these diseased states correlated with alterations noted by light microscopy and scanning and transmission electron microscopy. Specular microscopy can provide detailed in vivo cellular morphology of the ocular surface, obviating the need for tissue biopsy. Thus, specular microscopy is a valuable diagnostic technique available for the clinician to monitor changes of the diseased ocular surface.

Lipopolysaccharide changes in impermeability-type aminoglycoside resistance in Pseudomonas aeruginosa

Clinical isolates of Pseudomonas aeruginosa were examined for the basis of impermeability-type aminoglycoside resistance. Two apparently related burn isolate strains with high-level (strain 8803) and low-level (strain 13934) gentamicin resistance each had a plasmid. Transformation of the plasmid from either strain to P. aeruginosa PAO503 resulted in low-level gentamicin resistance. No mechanism for this resistance could be determined. Low-level gentamicin and streptomycin resistance from strain 8803 (but not 13934) was transduced with phage E79.tv2 to PAO503 without transfer of plasmid DNA. Transductants like strain 8803 showed absence or reduction of the lipopolysaccharide (LPS) "ladder" pattern of PAO503, had a change in chemical composition of LPS, and, like strain 8803, had a reduced capability to accumulate streptomycin. Comparison of the resistant clinical isolates 8803 and P10 with the apparently related but less-resistant strains 13934 and P10R, respectively, showed the latter strains had LPS ladder patterns and the former strains did not. Strain 8803 had normal outer membrane protein profiles, electron transport components, and transmembrane electrical potential relative to PAO503 and has been previously shown to have no detectable gentamicin-modifying enzymes and normal protein synthesis. We conclude that low-level impermeability-type aminoglycoside resistance in P. aeruginosa results from conversion of smooth LPS to superficial or deeper rough LPS phenotypes. High-level resistance apparently results from a plasmid-specified, but as yet unknown, mechanism combined with the preceding change in LPS structure.

Suppression by diets rich in fish oil of very low density lipoprotein production in man

The highly polyunsaturated fatty acids in fish oils lower the plasma triglyceride concentration. We have studied the effect of a diet rich in fish oil on the rate of production of the triglyceride-transporting very low density lipoprotein (VLDL). Seven subjects, five normal and two with hypertriglyceridemia received up to 30% of daily energy needs from a fish oil preparation that was rich in eicosapentaenoic acid and docosahexaenoic acid, omega-3 fatty acids with five and six double bonds, respectively. Compared with a diet similarly enriched with safflower oil (in which the predominant fatty acid is the omega-6 linoleic acid, with two double bonds), the fish oil diet lowered VLDL lipids and B apoprotein concentrations profoundly. High density lipoprotein lipids and A1 apoprotein were also lowered, but the effect on low density lipoprotein (LDL) concentration was inconsistent. The daily production or flux of VLDL apoprotein B, calculated from reinjected autologous 125I-labeled lipoprotein, was substantially less in six subjects studied after 3 wk of fish oil, compared with after safflower oil. This effect on flux was more consistent than that on the irreversible fractional removal rate, which was increased in the four normolipidemic but inconsistent in the hypertriglyceridemic subjects. This suggests that fish oil reduced primarily the production of VLDL. The daily production of VLDL triglyceride, calculated from the kinetics of the triglyceride specific radioactivity-time curves after [3H]glycerol was injected, also showed very substantial reductions in five subjects studied. The marked suppression in VLDL apoprotein B and VLDL triglyceride formation was found not to be due to diminished plasma total free fatty acid or plasma eicosapentaenoic flux, calculated during constant infusions of [14C]eicosapentaenoic acid and [3H]oleic acid in four subjects. In two subjects there was presumptive evidence for substantial independent influx of LDL during the fish oil diet, based on the precursor-product relationship between the intermediate density lipoprotein and LDL apoprotein B specific radioactivity-time curves.

Cardiopulmonary resuscitation at the Singapore General Hospital

Effective use of Cardiopulmonary Resuscitation (CPR) saves lives both in and out of hospitals. Yet, in Singapore, this practical skill is rarely taught even within the medical community. Observations from a CPR pilot training programme at the Singapore General Hospital expose this glaring deficiency in our health system. Urgent remedial measures are needed.

Comparison of the fluorescence and conformational properties of smooth and striated tropomyosin

In contrast to previous conformational studies with rabbit skeletal and cardiac tropomyosins, (i) when the cysteine side chains of chicken gizzard tropomyosin were reacted with 5,5'-dithiobis(2-nitrobenzoate), an interchain disulfide cross-link was not produced, (ii) when they were labeled with pyrenylmaleimide , excimer fluorescence was not observed, and (iii) when they were labeled with didansylcystine , a long-lived fluorescence component did not appreciably contribute to the fluorescence decay over a large temperature range including the major unfolding transition. In addition, the temperature dependence of the ellipticity at 222 nm did not reveal a pretransition prior to the main helix unfolding transition. This indicates that gizzard tropomyosin does not exhibit a localized chain-open state in the region of its cysteine residues, analogous to that seen with cardiac and skeletal tropomyosins, nor in any other region of the molecule. As a consequence, these observations suggest that gizzard tropomyosin is more rigid than striated tropomyosin.

Papain hydrolysis of X-phenyl-N-methanesulfonyl glycinates: a quantitative structure-activity relationship and molecular graphics analysis

The hydrolysis of 32 X-phenyl-N-methanesulfonyl glycinates by papain was investigated. It was found that the variation in the Michaelis constants could be rationalized by the following correlation equation: log 1/Km = 0.61 pi '3 + 0.46 MR4 + 0.55 sigma + 2.00 with a correlation coefficient of 0.945. In this expression, pi '3 is the hydrophobic constant for the more lipophilic of the two possible meta substituents, MR4 is the molar refractivity of 4-substituents, and sigma is the Hammett constant summed for all substituents. Using this equation, we designed, synthesized, and successfully predicted Km for a new congener intended to maximize binding (1/Km). The interactions involved in enzyme-substrate binding, as characterized by the correlation equation, are interpreted using a computer-constructed color three-dimensional-graphics molecular model of the enzyme active site. The nonenzymatic hydrolysis (both acid and basic) of phenyl hippurates yield rate constants which are well correlated by Hammett equations; however, log k for both acid and alkaline hydrolysis are not linearly related to log 1/Km or log kcat/Km.

Neonatal methadone withdrawal. Effect of two treatment regimens

Thirty-one infants exposed to methadone in utero who required pharmacologic treatment for withdrawal symptoms were randomly assigned to a paregoric or phenobarbital treatment group. Seven infants had symptoms too mild to require treatment. Respiratory rate, blood pH, PCO2, systolic BP, and serum thyroxine concentrations were measured on the 4th, 7th, and 14th days of life. Platelet counts were performed on the seventh and 14th days of life, and urinary catecholamine excretion was measured on the sixth day of life. Rates of weight gain were recorded during the second and third weeks of life. With the exception of a slightly higher blood PCO2 level in the phenobarbital-treated infants on day 7, no significant intergroup differences were observed in the treated infants. Paregoric-treated infants required a significantly longer period of treatment than phenobarbital-treated infants (22 v 17 days). This may have been due, at least in part, to the prolonged half-life and relatively high blood levels of phenobarbital present after cessation of therapy.

The rate of starch hydrolysis in vitro does not predict the metabolic responses to legumes in vivo

The aim of this study was to determine whether legumes in a physical form which is rapidly digested in vitro give rise to proportionately greater metabolic responses in vivo than legumes which are slowly digested in vitro. Samples of cooked whole and ground lentils were incubated in vitro with pancreatic amylase for 30 min and the percentage starch hydrolysis determined. Grinding the lentils before cooking resulted in a 5-fold increase in the rate of starch hydrolysis (whole lentils 12.1%, ground lentils 60.9%). For the in vivo studies six healthy, young, lean subjects consumed two test meals containing 50 g starch: whole lentils and lentils that had been ground finely before cooking. Postprandial glucose and insulin responses were measured over 4 h. Peak glucose and insulin responses occurred 60 min postprandially for the whole lentils and 30 min postprandially for ground lentils. Although the increase in plasma glucose after ground lentils (1.6 mM) was significantly higher (p less than 0.025) than that after whole lentils (0.9 mM), there was no difference in the magnitude of the insulin responses. These results indicate that, unlike for cereals, the rate of intestinal starch hydrolysis is not the major factor determining the metabolic responses to legumes. By virtue of their low postprandial glucose and insulin responses, irrespective of their physical form and digestibility, legumes would appear to be ideal for inclusion in the diet of diabetics.