Intra-aortic balloon pump complications: A five-year retrospective study of 283 patients

OBJECTIVE

To determine the type, incidence, and risk factors for complication with the intra-aortic balloon pump.

DESIGN

Descriptive, chart review.

SETTING

Midwestern community teaching hospital.

PATIENTS

Two hundred eighty-three patients with 287 intra-aortic balloon pump insertions from January 1, 1990, to December 31, 1994.

OUTCOME MEASURES

Complications of therapy.

RESULTS

Seventeen percent of balloon insertions resulted in minor complications, and 14 patients had major complications. Polychotomous logistic regression was used to determine which study risk factors were predictive of the development of minor or major complications in patients. Patients with longer balloon duration had an increased risk of a major complication; whereas smokers and patients with lower body mass index had an increased probability of the development of a minor complication.

The effects of high-intensity intermittent exercise on saliva IgA, total protein and alpha-amylase

The aim of this study was to assess the effect of an acute bout of high-intensity intermittent exercise on saliva IgA concentration and alpha-amylase activity, since this type of training is commonly incorporated into the training programmes of endurance athletes and games players. Eight well-trained male games players took part in the study. They reported to the laboratory after an overnight fast and performed a 60-min cycle exercise task consisting of twenty 1-min periods at 100% VO2max, each separated by 2 min recovery at 30% VO2max. Unstimulated whole saliva was collected over a 5-min period into pre-weighed tubes and analysed for total protein, saliva IgA and alpha-amylase. The saliva flow rate ranged from 0.08 to 1.40 ml x min(-1) at rest and was not significantly affected by the exercise. The performance of the intermittent exercise bout did not affect the saliva IgA concentration, but caused a five-fold increase in alpha-amylase activity (P<0.01 compared with pre-exercise) and a three-fold increase in total protein concentration (P<0.01). These returned to pre-exercise values within 2.5 h post-exercise. It has been suggested that IgA concentration should be expressed as the ratio to total protein concentration, to correct for any concentrating effect due to evaporative loss of saliva water when breathing through the mouth (as in strenuous exercise). The present study clearly demonstrates that this is not appropriate, since there is an increase in salivary protein secretion rate immediately after exercise (571+/-77 microg x min(-1) compared with 218+/-71 microg x min(-1) pre-exercise; P<0.05). The increased saliva alpha-amylase activity after exercise may improve the protective effect of saliva, since this enzyme is known to inhibit bacterial attachment to oral surfaces. The saliva alpha-amylase secretion rate was lower immediately pre-exercise than at any other instant, which may have been due to anticipatory psychological stress, although the subjects were all familiar with interval exercise. This emphasizes the need for true resting non-stressed control conditions in future studies of the effects of exercise on saliva constituents.

De novo 10q22 interstitial deletion

We describe a 4 month old male with a de novo interstitial deletion of chromosome 10q22. His clinical features included growth deficiency, developmental delay, ocular hypertelorism, posteriorly rotated ears, retrognathia, and fifth finger clinodactyly. He later developed dental lamina cysts of the alveolar ridge. To our knowledge, this is the first reported case of an interstitial deletion of 10q22.

Tuberculin skin test screening practices among US colleges and universities

CONTEXT

Concern about transmission of Mycobacterium tuberculosis on college campuses has prompted some schools to institute tuberculin skin test screening of students, but this screening has never been evaluated.

OBJECTIVE

To describe tuberculin skin test screening practices and results of screening in colleges and universities in the United States.

DESIGN AND SETTING

Self-administered mail and telephone questionnaire in November and December 1995 to a stratified random sample of US 2-year and 4-year colleges and universities.

MAIN OUTCOME MEASURES

Type of tuberculin screening required; types of schools requiring screening; number and rate of students with positive skin test results and/or diagnosed as having tuberculosis.

RESULTS

Of the 3148 US colleges and universities, 624 (78%) of 796 schools surveyed responded. Overall, 378 schools (61%) required tuberculin screening; it was required for all new students (US residents and international students) in 161 (26%) of 624 schools, all new international students but not new US residents in 53 (8%), and students in specific academic programs in 294 (47%). Required screening was more likely in 4-year vs 2-year schools, schools that belonged to the American College Health Association vs nonmember schools, schools with immunization requirements vs schools without, and schools with a student health clinic vs those without (P<.001 for all). Public and private schools were equally likely to require screening (64% vs 62%; P=.21). In the 378 schools with screening requirements, tine or multiple puncture tests were accepted in 95 (25%); test results were recorded in millimeters of induration in 95 (25%); and 100 (27%) reported collecting results in a centralized registry or database. Of the 168 (27%) of 624 schools accepting only Mantoux skin tests and reporting results for school years 1992-1993 through 1995-1996, 3.1% of the 348 368 students screened had positive skin test results (median percentage positive, 0.8%). International students had a significantly higher case rate for active tuberculosis than US residents (35.2 vs 1.1 per 100000 students screened).

CONCLUSIONS

Widespread tuberculin screening of students yielded a low prevalence of skin test reactors and few tuberculosis cases. To optimize the use of limited public health resources, tuberculin screening should target students at high risk for infection.

Weaver syndrome: autosomal dominant inheritance of the disorder

Weaver syndrome (WS), a condition first described in 1974 by Weaver et al., consists of macrosomia, advanced skeletal age, characteristic pattern of facial and radiographic anomalies, and contractures. Although there have been three reports of close relatives (sibs or both parent and offspring) affected with this condition, the syndrome generally occurs sporadically, and the recurrence risk in sporadic cases appears to be low. We report here on a family in which the propositus and his sister were born with the facial phenotype, club feet, and macrosomia characteristic of WS. Their father had macrosomia and macrocephaly as an adult, and childhood photos show clearly that he has WS. Two sisters of the propositus have had normal growth and development. The syndrome in this family appears to be inherited in an autosomal dominant fashion.

New methods for detection of anti-nuclear antibodies

Many different autoantibodies which react with a variety of different nuclear and cytoplasmic antigens have been described. Detection of some these antibodies has been shown to be clinically useful in a number of different autoimmune diseases. For many years, the detection of most of the clinically relevant antibodies was done with by immunofluorescence on tissue substrates and human cultured cell lines. Within the past few years, a number of technical advances has now made it possible to convert to enzyme immunoassay. The paper reviews the clinically relevant antibodies and discusses the variety of new methods which are now available for ANA detection in diagnostic laboratories.

The effect of severe eccentric exercise-induced muscle damage on plasma elastase, glutamine and zinc concentrations

The aim of this study was to determine if severe exercise-induced muscle damage alters the plasma concentrations of glutamine and zinc. Changes in plasma concentrations of glutamine, zinc and polymorphonuclear elastase (an index of phagocytic cell activation) were examined for up to 10 days following eccentric exercise of the knee extensors of one leg in eight untrained subjects. The exercise bout consisted of 20 repetitions of electrically stimulated eccentric muscle actions on an isokinetic dynamometer. Subjects experienced severe muscle soreness and large increases in plasma creatine kinase activity indicative of muscle fibre damage. Peak soreness occurred at 2 days post-exercise and peak creatine kinase activity [21714 (6416) U x l(-1) mean (SEM)] occurred at 3 days post-exercise (P < 0.01 compared with pre-exercise). Plasma elastase concentration was increased at 3 days post-exercise compared with pre-exercise (P < 0.05), and is presumably indicative of ongoing phagocytic leucocyte infiltration and activation in the damaged muscles. There were no significant changes in plasma zinc and glutamine concentrations in the days following eccentric exercise. We conclude that exercise-induced muscle damage does not produce changes in plasma glutamine or zinc concentrations despite evidence of phagocytic neutrophil activation.

Partners with reciprocal translocations: genetic counseling for the 'double translocation'

SV at age 2 years presented with multiple congenital anomalies including an absent left kidney, anal stenosis, vertebral abnormalities, partial sacral agenesis, microcephaly, dysmorphic facial features, growth deficiency, and developmental delay. She was found to have a complex chromosomal rearrangement derived from balanced translocations in each parent.

The effects of high-intensity intermittent exercise on the plasma concentrations of glutamine and organic acids

Glutamine is an essential substrate for the proper functioning of cells of the immune system. Falls in plasma glutamine concentration after exercise may have deleterious consequences for immune cell function and render the individual more susceptible to infection. The purpose of the present study was to examine changes in plasma glutamine concentration (measured using a validated enzymatic spectrophotometric method) following an acute bout of intermittent high-intensity exercise. Eight well-trained male games players took part in the study. Subjects reported to the laboratory following an overnight fast and performed a 1-h cycle exercise task consisting of 20 1-min periods at 100% maximal O2 consumption (VO2max) each separated by 2 min of recovery at 30% VO2max. Venous blood samples were taken before exercise and at 5 min, 1 h, 2.5 h, 5 h and 24 h post-exercise. Glutamine was measured by enzymatic spectrophotometric determination of the ammonia concentration before and after treatment of the plasma with glutaminase (EC 3.5.1.2). Plasma glutamine concentration did not fall in the immediate post-exercise period [pre-exercise 681 (23) microM compared with 663 (46) microM at 5 min post-exercise, mean (SEM)], but fell to 572 (35) microM at 5 h post-exercise (P < 0.05 compared with pre-exercise). Plasma lactate concentration rose to 8.8 (1.0) mM at the end of exercise and fell to 1.8 (0.4) mM at 1 h post-exercise, but plasma concentrations of free fatty acids and beta-hydroxybutyrate both rose substantially in the post-exercise period (to 240% and 400% of pre-exercise levels, respectively). The circulating leucocyte count increased significantly during exercise (P < 0.01), continued to increase in the hours following exercise and peaked at 2.5 h post-exercise (mainly due to a neutrophilia). The fall in the plasma glutamine concentration at 5 h post-exercise could be due to increased renal uptake of glutamine, which generally occurs in conditions of metabolic acidosis or due to a greater removal of glutamine from the plasma resulting from the elevated circulating leucocyte count.

Pregnancy outcome following maternal use of the new selective serotonin reuptake inhibitors: a prospective controlled multicenter study

CONTEXT

Although a large number of women of reproductive age use new selective serotonin reuptake inhibitors (SSRIs) and half of all pregnancies are unplanned, no data exist on the safety of these agents for the human fetus.

OBJECTIVE

To assess fetal safety and risk of fluvoxamine, paroxetine, and sertraline.

DESIGN

A prospective, multicenter, controlled cohort study.

SETTING

Nine Teratology Information Service centers in the United States and Canada.

PATIENTS

All women who were counseled during pregnancy following exposure to a new SSRI and followed up by the participating centers. Controls were randomly selected from women counseled after exposure to nonteratogenic agents.

MAIN OUTCOME MEASURES

Rates of major congenital malformations.

RESULTS

A total of 267 women exposed to an SSRI and 267 controls were studied. Exposure to SSRIs was not associated with either increased risk for major malformations (9/222 live births [4.1%] vs 9/235 live births [3.8%] in the controls, relative risk, 1.06, 95% confidence interval, 0.43-2.62) or higher rates of miscarriage, stillbirth, or prematurity. Mean (SD) birth weights among SSRI users (3439 [505] g) were similar to the controls (3445 [610] g) as were the gestational ages (39.4 [1.7] weeks vs 39.4 [1.9] weeks).

CONCLUSION

The new SSRIs, fluvoxamine, paroxetine, and sertraline, do not appear to increase the teratogenic risk when used in their recommended doses.

TAT results in a longitudinal study of bereaved college students

The authors analyzed projective data obtained from 141 college students who wrote stories on three separate occasions to selected cards from the Thematic Apperception Test (TAT). The students included 46 members of support groups for bereaved college students, 34 members of a bereavement control group, and 61 nonbereaved students. The study used a repeated-measures pretest-posttest control group design to gather longitudinal data about the trajectory of bereavement with and without support group intervention. Coders, who reached consistently high interrater reliability, looked for themes of death, grief, coping, and affiliation in the stories. Multivariate analysis of variance (MANOVA) and repeated-measures MANOVA tests were applied to analyze coding results. Overall MANOVA results indicated significant group differences in the responses to the TAT cards. Repeated-measures MANOVA found group differences in use of themes of death and grief and found Group x Time differences in maintaining a sense of self-efficacy while in a crisis. A majority of the stories contained affiliation imagery but without any group differences in the use of such imagery.

The proteinase-antiproteinase theory of emphysema: a speculative analysis of recent advances into the pathogenesis of emphysema

This review concerns the reasons why only an estimated 10-15% of patients with alpha-1-antitrypsin (A1AT) deficiency develop the destructive lung disease known as emphysema. The arguments presented revolve around the proteinase-antiproteinase balance in the 'microenvironment' of the epithelial space of the lung. Attention is focused on the balance between destructive enzymes such as neutrophil elastase and protective proteins such as A1AT, secretory leucocyte proteinase inhibitor (SLPI), human elastase inhibitor (HEI) and elafin. When neutrophil elastase is already attached to the elastin fibres the smaller molecules SLPI and elafin appear to be better inhibitors of this enzyme than larger inhibitors such as A1AT and HEI. Furthermore, SLPI and elafin may provide the first line of defence against proteinase attack from neutrophil elastase. In trying to explain the variability in the clinical expression of A1AT-deficiency and the development of emphysema, the importance of changes to A1AT, SLPI and elafin molecules induced by smoking and/or oxygen free radicals has been considered. It is possible that emphysema only develops in patients who have SLPI/elafin deficiency as well as A1AT deficiency.

Function of a rare variant of alpha-1-antitrypsin, phenotype P(i) EFranklin S, a poor inhibitor of human neutrophil elastase

A 31-year-old woman with the rare alpha-1-antitrypsin (A1AT) phenotype P(i) EFranklin S presented to this laboratory. Since little is known about the EFranklin protein, a study was established to investigate the biochemical properties of this glycoprotein, notably its inhibitory activity against human neutrophil elastase (HNE), compared with that of the more common A1AT variants M and Z. The serum A1AT level of 1.8 g/l (reference range 0.8-2.2 g/l) and anti-neutrophil elastase capacity (ANEC) value of 28 microM (reference range 15-42 microM) of this variant were normal. However, the association rate constant (AC) of the isolated and purified EFranklin protein 2.7 (0.4) x 10(6) M-1 s-1 at 25 degrees C was significantly lower compared with that in the normal M variant 9.1 (0.9) x 10(6) M-1 s-1. This implies that this form of A1AT is expressed at normal levels in serum but is functionally impaired as an inhibitor of HNE. The in vivo serum inhibition time of HNE was estimated to be 66 ms for the purified EFranklin protein compared with 20 ms for the M protein. While this protein is not an efficient inhibitor of HNE, there are sufficient molecules in the serum to achieve 100% inhibition of HNE and to protect the lung against proteinase attack. In conclusion, individuals who inherit the rare EFranklin variant in conjunction with the M or S A1AT molecules do not appear to have a high risk for the development of emphysema.

A simplified method for Ca2+ flux measurement on isolated human B cells that uses flow cytometry

A method for Ca2+ flux measurement on isolated human peripheral B cells that uses flow cytometry is described. B cells were isolated by anti-CD19 magnetic bead sorting, and Ca2+ flux was measured with the fluo-3 reagent on a standard single-laser flow cytometer. The response of B-cell stimulation by anti-immunoglobulin B (anti-IgM), anti-IgD, protein A, concanavalin A, and ionomycin was determined. Percentage of responder B cells, the level of Ca2+, and the time of peak stimulation were measured. Bound anti-CD19 monoclonal antibody coupled with small paramagnetic particles did not affect Ca2+ flux. All the isolated B cells responded maximally at 10s with stimulation by 8 microg of ionomycin. The average isolated preparation contains 70% IgM+ and 85% IgD+ cells, all of which showed peak stimulation with 10 microg of anti-IgM and anti-IgD per ml, respectively, at 30s. Only at high concentrations of 80 microg/ml, concanavalin A produced a slower response, peaking at 90 s after stimulation. Stimulation with 20 microg of protein A per ml resulted in Ca2+ flux in only 40 to 60% of cells that had a rapid response and maximal stimulation resembling the pattern of activation of ionomycin. B cells from three patients with mixed cryoglobulinemia with high concentrations of monoclonal rheumatoid factors showed stimulation with aggregated IgG, whereas those from healthy control subjects did not, demonstrating the applicability of the methodology to detection of specific antigen stimulation of B cells. This methodology may be useful in testing the functional capacity of B cells in a variety of diseases. The methodology may also prove useful in studying antigen-specific B-cell responses when they involve a significant percentage of B cells.

Insulinotropic action of methyl pyruvate: enzymatic and metabolic aspects

The metabolism of methyl pyruvate was compared to that of pyruvate in isolated rat pancreatic islets. Methyl pyruvate was found to be more efficient than pyruvate in supporting the intramitochondrial conversion of pyruvate metabolites to amino acids, inhibiting D-[5-3H]glucose utilization, maintaining a high ratio between D-[3,4-14C]glucose or D-[6-14C]glucose oxidation and D-[5-3H]glucose utilization, inhibiting the intramitochondrial conversion of glucose-derived 2-keto acids to their corresponding amino acids, and augmenting 14CO2 output from islets prelabeled with L-[U-14C]glutamine. Methyl pyruvate also apparently caused a more marked mitochondrial alkalinization than pyruvate, as judged from comparisons of pH measurements based on the use of either a fluorescein probe or 14C-labeled 5,5-dimethyl-oxazolidine-2,4-dione. Inversely, pyruvate was more efficient than methyl pyruvate in increasing lactate output and generating L-alanine. These converging findings indicate that, by comparison with exogenous pyruvate, its methyl ester is preferentially metabolized in the mitochondrial, rather than cytosolic, domain of islet cells. It is proposed that both the positive and the negative components of methyl pyruvate insulinotropic action are linked to changes in the net generation of reducing equivalents, ATP and H+.

Insulinotropic action of methyl pyruvate: secretory, cationic, and biosynthetic aspects

Methyl pyruvate was found to exert a dual effect on insulin release from isolated rat pancreatic islets. A positive insulinotropic action prevailed at low concentrations of D-glucose, in the 2.8 to 8.3 mM range, and at concentrations of the ester not exceeding 10.0 mM. It displayed features typical of a process of nutrient-stimulated insulin release, such as decreased K+ conductance, enhanced Ca2+ influx, and stimulation of proinsulin biosynthesis. A negative insulinotropic action of methyl pyruvate was also observed, however, at a high concentration of D-glucose (16.7 mM) and/or at a high concentration of the methyl ester (20.0 mM). It was apparently not attributable to any adverse effect of methyl pyruvate on ATP generation, but might be due to hyperpolarization of the plasma membrane. The ionic determinant(s) of the latter change was not identified. The dual effect of methyl pyruvate probably accounts for an unusual time course of the secretory response, including a dramatic and paradoxical stimulation of insulin release upon removal of the ester.

Kinetic characterisation of alpha-1-antitrypsin F as an inhibitor of human neutrophil elastase

Patients homozygous for the Z allele of alpha-1-antitrypsin (alpha 1AT) have very low serum levels and are predisposed to emphysema. There have also been reports of emphysema being associated with the heterozygous phenotype FZ. To investigate whether F alpha 1AT was dysfunctional, the inhibitory activity of F alpha 1AT against human neutrophil elastase (HNE) was compared with that of common alpha 1AT phenotypes. Time-dependent inhibition of HNE by alpha 1AT was used to calculate the association rate constant (k assoc) for M, MZ, FM, FZ, F (partially purified from FZ or FS), Z and S alpha 1AT phenotypes in human sera. The results for k assoc at 25 degrees C were 9.1 (SD 0.9), 9.7 (SD 0.9), 8.0 (SD 0.8), 4.0 (SD 0.4), 4.2 (SD 0.8), 5.1 (SD 0.6) and 8.6 (SD 0.6) x 10(6) M-1s-1 respectively. F was found to have reduced activity much like that of Z, the alpha 1AT most commonly associated with emphysema. MZ (low risk for disease) and FZ heterozygotes had similar intermediate alpha 1AT levels. However the in vivo inhibition time for FZ was almost three times longer than for MZ, indicating greater exposure to proteolytic damage from free elastase for FZ than MZ individuals. In conclusion, F alpha 1AT is expressed in serum at low normal levels but is dysfunctional in its ability to inhibit HNE. Individuals who coinherit the F and a deficiency allele such as Z or Null, are likely to have a high risk for the development of emphysema. The disease risk for F homozygotes remains to be determined.