Long-term effects of therapy on respiratory health

Only scant information is available on the long-term consequences to respiratory health of treatment with bronchodilators and oral corticosteroids. In the present study, we aimed to gain more information about these consequences. We examined 712 men working in the Paris area, by means of a subjective assessment of whether their respiratory health worsened or improved from 1960 to 1972, the decline in forced expiratory volume in one second (FEV1) over this time-period, and mortality from 1972 to 1992, in relation to respiratory therapy dispensed during a 2 year period in 1970-1971, as recorded in social security reimbursement records. As expected, subjects with respiratory symptoms or airflow limitation were more likely to have been prescribed respiratory therapy. After accounting for the effect of lung function level and smoking, subjects dispensed inhaled beta-agonists were likely to feel their condition had worsened and had a greater decline in FEV1 from 1960 to 1972. Among subjects with airflow limitation who reported asthma or persistent wheeze, having been dispensed oral corticosteroids on an intermittent basis was associated with improved survival (relative risk (RR) 0.32; 95% confidence interval (95% CI): 0.10-0.91) after adjusting for FEV1 level and smoking category. Our results add to the evidence that regular use of beta-agonist bronchodilators may be associated with adverse effects on respiratory health, whilst intermittent use of corticosteroids may be of long-term benefit.

Socioeconomic status and lung function among primary school children in Canada

We examined the relationship of lung function level to socioeconomic status (SES) using a cross-sectional design among 989 primary school children selected from 18 Montreal schools and studied between April 1990 and November 1992. Information on each child's health, demographics, home exposure to tobacco smoke, pets, and cooking and heating fuel used in the child's home was collected by questionnaire. Spirometry was performed at school. Parental occupation was used to establish SES. After adjusting for personal, familial, and environmental factors, in boys but not in girls, FEV1 and FVC were progressively larger in higher categories of SES (p < 0.001 for linear trend). After taking into account the effect of multiple comparisons and adjusting for personal, familial, and environmental factors, boys from families in the lowest category of SES were found to have an FEV1 lower by 8.2% (95% CI, -13.8 to -2.1) and an FVC lower by 8.1% (95% CI, -13.4 to -2.6) when compared with the most advantaged. These results provide evidence that socioeconomic status, independent of common indoor exposures, is a risk factor for lower FEV1 and FVC among boys.

Increased morbidity and mortality related to asthma among asthmatic patients who use major tranquillisers

OBJECTIVE

To assess the potentially increased risk of death or near death from asthma in asthmatic patients with psychosis.

DESIGN

Case-control study.

SETTING

The computerised health databases of the Canadian province of Saskatchewan.

SUBJECTS

131 cases of death or near death from asthma identified within a cohort of asthmatic patients; 3930 matched non-cases. EXPOSURE AND OUTCOME MEASURES: The exposure of interest was the use of major tranquillisers in the period before an outcome event. Outcomes included death or near death from asthma.

RESULTS

Crude analyses showed that asthmatic patients who had used major tranquillisers in the previous 12 months were at a 3.2 (95% confidence interval 1.4 to 7.5) times greater risk of death or near death from asthma than asthmatic patients who did not use major tranquillisers. Past users of major tranquillisers who had recently discontinued use were at a particularly high risk (relative risk 6.6; 2.5 to 17.6). Adjustment for use of antiasthma drugs and other confounders abolished this excess risk.

CONCLUSIONS

Asthmatic patients who use major tranquillisers seem to be at an increased risk of death or near death from asthma. Physicians treating asthmatic patients with a history of use of major tranquillisers should exercise greater caution with regard to management of such patients.

Usual dietary salt intake and asthma in children: a case-control study

BACKGROUND

A decline in host resistance due to an alteration in diet--primarily of salt--was recently put forward as a possible explanation for rising rates of asthma.

METHODS

A case-control study was conducted in participants in a prevalence survey which included 187 children with asthma (defined by prior diagnosis and/or a decline in forced expiratory volume in one second (FEV1) of > or = 10% after exercise) and 145 age and sex matched controls. Subjects were selected from 989 children aged 5-13 years attending 18 elementary schools on the island of Montreal. Usual dietary salt intake was estimated from a food frequency questionnaire administered to the mother, and a salt intake score was used to group the children into quartiles from I (lowest) to IV (highest salt intake). Bronchial hyperresponsiveness to methacholine was assessed by Yan's method. Cases and controls were combined in one group to examine the relationship of salt intake to bronchial hyperresponsiveness to methacholine. Methacholine responsiveness was expressed as a dose-response slope and ranks of dose-response slopes were used in the analysis.

RESULTS

After accounting for important confounding variables, there was no association between asthma and salt intake, while methacholine dose-response slope ranks increased with increasing salt intake and methacholine responsiveness was greater in the highest quartile than in the lowest quartile of salt intake. The median dose-response slopes in % fall in FEV1 per mumol methacholine for quartiles I, II, III, and IV were 5.4, 5.9, 7.7, and 8.7.

CONCLUSIONS

No association was found between asthma or exercise-induced bronchospasm and dietary salt intake. Bronchial hyperresponsiveness to methacholine did, however, appear to increase with greater salt intake, but the relevance of this association to asthma is unclear.

Bone marrow transplantation for infantile malignant osteopetrosis

PURPOSE

Most patients diagnosed with malignant osteopetrosis die during infancy or early childhood from hemorrhage and infection due to bone marrow failure. Allogeneic bone marrow transplantation (BMT) has been reported to provide curative therapy for this disorder. We report our experience with eight patients with malignant osteopetrosis who underwent BMT.

PATIENTS AND METHODS

Between May 1987 and August 1992, eight children with malignant osteopetrosis underwent allogeneic BMT. Median age at BMT was 9 months (range, 2-36 months). Six patients received marrow from HLA-identical sibling donors, one from phenotypically matched father, and one from a one antigen mismatched father. BMT conditioning for all patients was busulfan 16 mg/kg and cyclophosphamide 200 mg/kg each administered over 4 days. Graft versus host disease (GVHD) prophylaxis included cyclosporin A in six patients or cyclosporin A and methotrexate in two patients.

RESULTS

Six patients, including those who received bone marrow from their father's, engrafted as documented by bone marrow biopsy showing an increase in osteoclasts in all cases and by chromosomal analysis in four patients. Two patients died without engraftment. Three out of six patients engrafted are alive and well at the follow-up of 48, 63, and 81 months. Serum calcium, alkaline, and acid phosphatase levels normalized within 2 months. These patients have full bone marrow reconstitution. Serial radiologic studies revealed bone marrow remodelling and a new nonsclerotic bone formation. Vision improved dramatically in the youngest patient.

CONCLUSION

BMT offers cure to patients with malignant osteopetrosis with reconstitution of bone marrow and correction of metabolic disturbances. In our experience, reversibility in neurosensory deficit is possible when BMT is done at an early age.

Asthma medications and disease exacerbations: an epidemiological study as a method for asthma surveillance

Recent experimental and epidemiological studies have suggested that outcomes of asthma are significantly influenced by treatment patterns. This study was conducted in order to investigate the links between treatment patterns in asthmatics and occurrence of disease exacerbations. We performed a nested case-control study in a cohort of 680 asthmatics identified between 1986 and 1991 in a drug dispensing database. After validation in a pilot study, the intermittent use of oral corticosteroids was used as a proxy for asthma exacerbations. Cases with an exacerbation (n=133) were pair-wise matched with controls. The type of medications used for the usual treatment of asthma were examined in relation to the risk of asthma exacerbation. The use of oral xanthines and inhaled fenoterol but not of inhaled salbutamol, corticosteroids, cromoglycate and ipratropium bromide was associated with an increased probability of asthma exacerbation. Within the cohort, the proportion of subjects dispensed inhaled corticosteroids rose from 12 to 27% between 1986 and 1991. The proportion of subjects using inhaled bronchodilators without inhaled corticosteroids also decreased over this period of time. The identification of markers of asthma exacerbations made it possible to link the probability of adverse outcome risk for such exacerbations with treatment patterns. This method could be useful in further development of asthma surveillance using drug dispensing databases.

Antipyrine clearance and metabolite excretion in Saudi patients with non-alcoholic chronic liver disease

In this report, we examined the hepatic microsomal enzyme activity in 34 Saudi patients with chronic liver disease (CLD) and in 21 healthy Saudi subjects by measuring antipyrine clearance (APCI) and the fraction (%) of antipyrine (AP) dose excreted in urine unchanged (fAP) and in the form of its main metabolites: 3-hydroxymethylantipyrine (fHMAP), norantipyrine(fNORAP), and 4-hydroxyantipyrine (f4OHAP). While APCI, fHMAP, fNORAP, f4OHAP were significantly reduced in patients with CLD, fAP was significantly higher in these patients. Correlation was observed between serum albumin and APCI, fHMAP, fNORAP, or f4OHAP and between each two of the last three variables. We conclude that Saudis with CLD have uniform rather than selective reduction of hepatic microsomal enzyme activity and that serum albumin is a sensitive indicator of this activity.

Socioeconomic status and indicators of asthma in children

Differential access and utilization of medical care by the poor and rich may contribute to differences in asthma prevalence. We therefore studied the relationship of socioeconomic status (SES) to various indicators of asthma in the Canadian context of universal access to medical care. Information on respiratory symptoms, demographics, and home exposures of 1,111 primary school children was collected by questionnaire. Parental occupation was used to establish SES. Exercise-induced bronchospasm (EIB) after a 6-min free-running test was our measure of airways responsiveness and was available for 989 children. As compared with children from the most advantaged homes, children from the least advantaged homes were more likely to present EIB (OR: 2.26, 95% CI: 1.12 to 4.58) and to report night cough (OR: 2.30, 95% CI: 1.04 to 5.06) and cough with mucus (OR: 3.15, 95% CI: 1.06 to 9.33), while there was no significant excess of the report of wheeze or diagnosed asthma. Among factors potentially linked to SES, the presence of a cat at home (OR: 1.63, 95% CI: 1.02 to 2.61) and lower respiratory infection before 2 yr of age were associated with an excess of EIB (OR: 1.71, 95% CI: 1.16 to 2.52). Our results suggest that unidentified environmental factors contribute to the excess asthma morbidity in poor children.

Relationship between antipyrine metabolism and acetylation phenotype in health and chronic liver diseases

The authors examined the activity of N-acetyltransferase and that of microsomal P-450 isoenzymes in health and hepatic disease state by determining the acetylation phenotype and the total (CLAP) and metabolic clearances of antipyrine to form norantipyrine or N-demethylantipyrine (MCLnora), 3-hydroxymethylantipyrine (MCLhma), and 4-hydroxyantipyrine (MCLha) in 21 healthy subjects and in 33 patients with chronic liver diseases (CLD) and investigated the relationship between the activities of these two enzyme systems. The acetylation phenotype was determined according to the urinary caffeine metabolites test. The mean and (SEM) of CLAP, MCLhma, MCLha, and MCLnora in healthy subjects were 2.42 (0.264), 0.193 (0.031), 0.322 (0.045), and 0.288 (0.04) L/h, and those observed in patients with CLD were 0.98 (0.1), 0.076 (0.015), 0.131 (0.026), 0.103 (0.022) L/h, respectively. The prevalence of fast acetylation among the healthy subjects and patients with CLD was 38% and 39%, respectively. Although all metabolic clearances appear to be reduced in healthy slow acetylators, the reduction was only significant in MCLnora, indicating a direct association between the activity of N-acetyltransferase and that of P-450 IIIA3 responsible for the N-demethylation of antipyrine. Conversely, slow acetylators with CLD exhibited significantly higher CLAP and near-significantly larger metabolic clearances including MCLnora, which suggests that P-450 activity in fast acetylators is more sensitive to chronic liver diseases than in slow acetylators.

Passive smoking and evolution of lung function in young adults. An 8-year longitudinal study

The objective of the study was to examine the relation between exposure to environmental tobacco smoke (ETS) and the rate of change in ventilatory lung function in young adults during a study period of 8 years, with an additional aim to recognize susceptible subgroups. The study population consisted of 117 never smokers, who were 15-40 years of age at the time of an initial examination when they underwent spirometry and a standardized interviewer-administered questionnaire on respiratory health, and were re-examined 8 years later. Lifetime exposure to ETS at home and at work before the start of the study was ascertained at an early stage of the study, and exposure during the study period was recorded at the 8-year examination. The relations between home and work ETS exposure before and during the study period and the rate of change in forced expiratory volume in one second (delta FEV1 in ml/yr) and in mean forced expiratory flow during the middle half of the forced vital capacity (delta FEF25-75 in 1/sec/yr) were studied in linear regression models including potential confounders and other determinants of the outcome. There was no statistically significant relation between ETS exposure during or before the study period and evolution of FEV1 or FEF25-75. The 95% confidence intervals of the estimates indicated that ETS exposure was unlikely to have a physiologically relevant effect. A statistically significant but physiologically unimportant relation was observed between cumulative home ETS exposure before the study and delta FEV1 in the subgroup of subjects 25 years of age or younger. There was no evidence of modification by atopy, wheezing or gender. The results suggest that exposure to environmental tobacco smoke in young adulthood at home and in office work environment does not lead to a clinically important ventilatory impairment in such exposure levels as experienced in Canadian housing conditions. This does not refute the possibility that higher exposure due to more frequent smoking in smaller indoor spaces with lower rates of ventilation may be harmful.

Systemic amphotericin B versus fluconazole in the management of antibiotic resistant neutropenic fever--preliminary observations from a pilot, exploratory study

A pilot exploratory study was undertaken to collect preliminary information relating to safety and overall outcome in using intravenous fluconazole (FLUC) for managing antibiotic resistant neutropenic fever (ARNF), with the objective of assessing feasibility of performing a larger prospective controlled study. Patients who were neutropenic from treatment for leukaemia or bone marrow transplantation, received either fluconazole (FLUC) or amphotericin B (AB). Eight of 16 patients (50%) on FLUC and 21 of 25 patients (84%) on AB defervesced; the mean time to defervescence was 11.0 +/- 10.0 days for FLUC compared to 7.7 +/- 6.3 days for AB, and a similar proportion in each treatment group defervesced within 5 days (50% vs. 52%), respectively. Six of 16 patients (37.5%) on FLUC and three of 25 patients (12%) on AB developed overt invasive fungal disease, including pulmonary aspergillosis (FLUC 4 cases, AB 2 cases) and invasive candidiasis (FLUC 2 cases, AB 0 cases). The mean time to these events was 19.5 +/- 13.4 (FLUC) and 9.0 +/- 3.6 (AB) days. The fungal related mortality rates were higher in the FLUC group: five of 16 patients (31%) vs. two of 25 patients (18%) died respectively; the time to fungal death was 43.2 +/- 18.2 (FLUC) and 25.0 +/- 18.4 (AB) days. This tendency towards a more favourable outcome in patients on AB may have been due to absence of prior fluconazole prophylaxis in patients subsequently receiving IV FLUC. Analysis of a small subgroup of patients who had all received prior prophylaxis with clotrimazole only, indicated that a greater number of patients subsequently receiving IV FLUC died from fungal disease (5/16 vs.0/6, P = 0.09).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of cytokine-mediated modulation of nm23 expression on the invasion and metastatic behavior of B16F10 melanoma cells

The molecular mechanisms of tumor invasion and metastasis are yet to be fully elucidated. A potential tumor-metastasis-suppressor gene nm23 has been described in certain rodent and human tumors. In the present study, we examined the potential anti-invasive and anti-metastatic effect of nm23 gene in B16F10 cells, a malignant murine melanoma cell line. Transfection of nm23 gene into B16F10 melanoma cells resulted in significant suppression of the invasiveness and metastatic ability of melanoma cells and significantly enhanced the survival of tumor-bearing mice. B16F10 melanoma cells transfected with nm23 produced significantly less soluble ICAM-I and were more susceptible to LAK-cell-mediated cytotoxicity. Co-culture of B16F10 melanoma cells with IL-2 had no effect on nm23 expression, whereas treatment with PGE2, TNF-alpha and IFN-gamma resulted in down-regulation of nm23 expression. Concomitantly, in vivo treatment with TNF-alpha or IFN-gamma in experimental mice increased pulmonary metastases and lowered the overall survival period, as compared with IL-2 treatment alone. These results provide evidence that nm23, in addition to its anti-metastatic function, could also be involved in modulating tumor-target-structure expression, in down-regulating invasive potential and in production of soluble intracellular adhesion molecules. The down-regulation of nm23 by TNF-alpha, IFN-gamma and particularly by PGE2 warrants re-examination of current immunotherapeutic protocols and of the role played by PGE2 in tumor progression.

Antipyrine clearance and metabolite excretion in patients with chronic hepatitis C

BACKGROUND/AIMS

Our aim was to study whether chronic hepatitis C affects the three metabolic pathways of the model drug antipyrine differently.

METHODS

We measured antipyrine clearance from saliva as well as urinary excretion of its main metabolites 4-hydroxy-antipyrine, 3-hydroxy-methyl-antipyrine, and nor-antipyrine in 24 patients with chronic hepatitis C and in 21 healthy control subjects. Due to incomplete urine collection, 12 liver patients and three controls were excluded.

RESULTS

Antipyrine clearance (mean +/- SD) was significantly lower in patients with chronic hepatitis C, 1.2 +/- 0.7 l.h-1 (n = 12), than in controls (n = 18), 2.2 +/- 1.0 l.h-1 (p = 0.006). The urinary excretion of each of the metabolites was depressed to an equal extent in liver patients. The severity of the liver disease, as assessed by Child Pugh score, serum albumin and bilirubin, correlated significantly with antipyrine clearance and urinary excretion of the metabolite 3-hydroxy-methyl-antipyrine. The hepatitis activity index (Knodell) correlated with 3-hydroxy-methyl-antipyrine and 4-hydroxy-antipyrine, only.

CONCLUSIONS

Moderate-severe chronic hepatitis C does not seem to depress the three main metabolic pathways of antipyrine differently.

The lymphoid transcription factor LyF-1 is encoded by specific, alternatively spliced mRNAs derived from the Ikaros gene

The lymphocyte-specific DNA-binding protein LyF-1 interacts with a critical control element in the terminal deoxynucleotidyltransferase (TdT) promoter as well as with the promoters for other genes expressed during early stages of B- and T-cell development. We have purified LyF-1 and have obtained a partial amino acid sequence from proteolytic peptides. The amino acid sequence suggests that LyF-1 is a zinc finger protein encoded by the Ikaros gene, which previously was implicated in T-cell development. Recombinant Ikaros expressed in Escherichia coli bound to the TdT promoter, and antisera directed against the recombinant protein specifically blocked the DNA-binding activity of LyF-1 in crude extracts. Further analysis revealed that at least six distinct mRNAs are derived from the Ikaros/LyF-1 gene by alternative splicing. Only two of the isoforms possess the N-terminal zinc finger domain that is necessary and sufficient for TdT promoter binding. Although both of these isoforms bound to similar sequences in the TdT, lambda 5, VpreB, and lck promoters, one isoform contains an additional zinc finger that resulted in altered recognition of some binding sites. At least four of the Ikaros/LyF-1 isoforms were detectable in extracts from B- and T-cell lines, with the relative amounts of the isoforms varying considerably. These data reveal that the LyF-1 protein is encoded by specific mRNAs derived from the alternatively-spliced Ikaros gene, suggesting that this gene may be important for the early stages of both B- and T-lymphocyte development.

Elimination studies of antipyrine and its metabolites in healthy Saudi Arabians

1. We measured the antipyrine clearance in 18 healthy Saudi subjects and determined the urinary excretion of three of its metabolites: 4-hydroxyantipyrine (4-OH AP), norantipyrine (NOR AP) and 3 hydroxymethylantipyrine (3-OHM AP) in 21 subjects. 2. The mean +/- SD of the antipyrine clearance was 2.4 +/- 1.1 h-1 (range 1.0-5.5 l h-1) and the corresponding value per kg body weight was 0.6 +/- 0.2 ml min-1 kg-1. Urinary excretion of antipyrine (AP), 4-OH AP, NOR AP and 3-OHM AP expressed as a percentage of the oral dose of antipyrine given was 2.8 +/- 2.2, 14.5 +/- 6.9, 12.3 +/- 5.6 and 7.6 +/- 3.2 respectively. 3. Compared to Africans, Saudis preferentially metabolize AP to NOR AP and compared to Caucasians to 3-OHM AP, rather than to 4-OH AP. These discrepancies may reflect age differences between the study populations rather than genetic or ethnic variations.

Patterns of increasing beta-agonist use and the risk of fatal or near-fatal asthma

The association between the use of inhaled beta-agonists by metered-dose inhaler and the risk of fatal or near-fatal asthma has been demonstrated. It shows that asthmatics who use one canister of beta-agonist per month more than the number used by other similar asthmatics have twice the risk of fatal or near-fatal asthma. The present investigation assesses the magnitude of this excess risk when an asthmatic increases his/her own monthly use of inhaled beta-agonists over time. From a previous nested case-control study of 129 deaths and near-deaths from asthma (cases) and 655 controls from a cohort of 12,301 asthmatics, the subset using at least 12 inhalers during the 12 month study period was identified (97 cases and 258 controls). A profile score, ranging 0-11, was formed to quantify the patterns of beta-agonist use over time for each subject, covering the entire spectrum extending from decreasing to increasing use. The relative risk was 15.2 (95% confidence interval (CI) 2.4-96.2) per unit increase of the profile score in subjects with a pattern of increasing beta-agonist use (profile score of 6.5 or more), but this relative risk was only 1.5 (95% CI 0.8-2.6) per unit when the profile score was less than 6.5 (non-increasing use). This relative risk was independent of the risk associated with the total quantity of beta-agonist use in the 12 month period, which remained around 1.6 (95% CI 1.3-2.0) per inhaler per month.(ABSTRACT TRUNCATED AT 250 WORDS)

Elimination of antipyrine and its metabolites in interferon treated hepatitis C

1. To study the effect of interferon on hepatic drug metabolism in chronic hepatitis C, we examined nine patients before and at the end of 6 months of interferon treatment. 2. Routine liver function was determined together with the salivary clearance of antipyrine and the 48 h urinary excretion of the main metabolites of antipyrine: 4-hydroxyantipyrine, 3-hydroxymethylantipyrine and norantipyrine before and after 6 months of interferon treatment. 3. Liver pathology, routine liver function, and antipyrine metabolism remained unchanged after patients were treated for 6 months with interferon for a histologically advanced but clinically compensated chronic hepatitis C.

Myelopathy after intrathecal chemotherapy. A case report with unique magnetic resonance imaging changes

BACKGROUND

Paraplegia caused by intrathecal chemotherapy has no known pathognomonic features and is a diagnosis of exclusion.

METHODS

The authors reported the clinical and neuroimaging findings in one patient with this syndrome.

RESULTS

The patient had severe paraplegia with urinary retention and impaired pain and touch sensation below T-10 with sparing of proprioception and vibration sense. Magnetic resonance imaging (MRI) scan showed diminished intensity throughout the central cervical spinal cord. Post-gadopentetate dimeglumine enhancement was scattered throughout the cervical spinal cord and in two areas of the dorsal spinal cord. Axial views of the cervical spinal cord showed that this enhancement was limited to the lateral columns.

CONCLUSIONS

The MRI in myelopathy due to intrathecal chemotherapy may show a unique pattern of postgadopentetate dimeglumine enhancement limited to the lateral columns of the spinal cord. However, two recently encountered patients with the same syndrome did not show similar changes.