Air quality influence on chronic obstructive pulmonary disease (COPD) patients' quality of life.

UNLABELLED: Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death. The relationship between urban air pollution and its short-term health effects on patients suffering from COPD is confirmed. However, information about the impact of air pollutants upon the quality of life (QOL) in patients with COPD is lacking. Through a cross-sectional survey, this study investigates such impact in terms of the scores of the (Chinese) chronic respiratory questionnaire (CCRQ) and the measurements of indoor air quality (IAQ), lung function and Moser's activities of daily living (ADL). Using Yule's Q statistic with a cutoff |Q|>0.7 to identify the strong relationships between environmental parameters and CRQ sub-scores, this study reveals that patient emotion is strongly associated with indoor environmental quality although the evidence of a causal relationship between them needs further research. PRACTICAL IMPLICATIONS: As QOL in patients with COPD and indoor environmental parameters are strongly associated, indoor air pollutants must be monitored for related studies in the future.

Mathematical models for accurate prediction of atmospheric visibility with particular reference to the seasonal and environmental patterns in Hong Kong.

Atmospheric visibility impairment has gained increasing concern as it is associated with the existence of a number of aerosols as well as common air pollutants and produces unfavorable conditions for observation, dispersion, and transportation. This study analyzed the atmospheric visibility data measured in urban and suburban Hong Kong (two selected stations) with respect to time-matched mass concentrations of common air pollutants including nitrogen dioxide (NO(2)), nitrogen monoxide (NO), respirable suspended particulates (PM(10)), sulfur dioxide (SO(2)), carbon monoxide (CO), and meteorological parameters including air temperature, relative humidity, and wind speed. No significant difference in atmospheric visibility was reported between the two measurement locations (p > or = 0.6, t test); and good atmospheric visibility was observed more frequently in summer and autumn than in winter and spring (p < 0.01, t test). It was also found that atmospheric visibility increased with temperature but decreased with the concentrations of SO(2), CO, PM(10), NO, and NO(2). The results showed that atmospheric visibility was season dependent and would have significant correlations with temperature, the mass concentrations of PM(10) and NO(2), and the air pollution index API (correlation coefficients mid R: R mid R: > or = 0.7, p < or = 0.0001, t test). Mathematical expressions catering to the seasonal variations of atmospheric visibility were thus proposed. By comparison, the proposed visibility prediction models were more accurate than some existing regional models. In addition to improving visibility prediction accuracy, this study would be useful for understanding the context of low atmospheric visibility, exploring possible remedial measures, and evaluating the impact of air pollution and atmospheric visibility impairment in this region.

An approach to assessing the probability of unsatisfactory radon in air-conditioned offices of Hong Kong.

In order to maintain an acceptable Indoor Air Quality (IAQ), policies, strategies and guidelines have been developed worldwide and exposure concentrations of the indoor radon have been specified. Mapping indoor radon levels for a region could be done with intensive measurements on a large number of samples. To obtain the most accurate estimate of the levels with the uncertainties specified, a statistical model has been developed in this study to predict the fractions of samples in a region having an average radon level above the action levels of 150Bqm(-3) and 200Bqm(-3). The model was based on a transformation of the variation from a small sample set of data to a population geometric distribution via an estimator, known as the 'sample correction factor'. Using a dataset from a cross-sectional measurement of indoor radon levels in 216 Hong Kong offices, where the mean was 37.2Bqm(-3) and the 68% range was from 17.3Bqm(-3) to 80.3Bqm(-3), the 'sample correction factor' was evaluated and tested by the Monte-Carlo simulations. The model estimates of the fractions above the indoor radon action levels 150Bqm(-3) and 200Bqm(-3) (1.2-7.7% and 0.4-4.1% for a sample size of 20, 2.8-5.1% and 0.8-2.4% for a sample size of 60) were demonstrated to be consistent with those determined from the dataset (3.5% and 1.4%). With the 'sample correction factor' thus quantified, it will be possible to provide the required data for the policymakers making appropriate decisions on resources and manpower management.

Determination of the distribution of fatty acids and diethylstilbestrol between serum albumin and alpha-fetoprotein by concanavalin A affinity chromatography.

The distribution of fatty acids and diethylstilbestrol between serum albumin and alpha-fetoprotein was measured in vitro by a new method based on the separation of the two proteins by virtue of the binding specificity of concanavalin A for the carbohydrate moiety of alpha-fetoprotein. Human and bovine proteins were investigated. It was found that palmitate and oleate were distributed almost equally between albumin and alpha-fetoprotein, while docosahexaenoate and diethylstilbestrol bound preferentially to alpha-fetoprotein even at an albumin: alpha-fetoprotein ratio of 10:1. The results confirm the binding specificity of alpha-fetoprotein for polyunsaturated fatty acids and also show that alpha-fetoprotein binds diethylstilbestrol much more strongly than albumin does. This suggests that alpha-fetoprotein may play a role in the fetal uptake of diethylstilbestrol.

Cardiomyopathy associated with nonendemic selenium deficiency in a Caucasian adolescent.

We describe a girl aged 17 y who died after a cardiac arrest secondary to septic shock. At autopsy, the enlarged, soft, and flabby heart showed microscopic evidence of acute myocardial infarction, myocardial edema, myocardiocyte loss, replacement fibrosis in the interventricular septum, and right and left ventricular hypertrophic nucleomegaly. The pathological diagnosis was that of cardiomyopathy due to prolonged selenium deficiency. The patient had been on total parenteral nutrition for 17 mo, following extensive bowel resection for intractable pain, nausea, and vomiting caused by chronic idiopathic intestinal pseudoobstruction. Seven months before death, when severe biochemical selenium deficiency was diagnosed, supplemental selenium was added to the infusion, and plasma selenium concentrations increased. In long-standing selenium deficiency, sepsis may contribute the final insult to a damaged myocardium, triggering symptomatic cardiac failure and sudden death.

Guanosine triphosphate cyclohydrolase I deficiency: early diagnosis by routine urine pteridine screening.

A deficiency of hepatic guanosine triphosphate cyclohydrolase I is reported in a 4-month-old infant in whom positive results on a Guthrie phenylketonuria test in the neonatal period were found. Because of the significantly elevated serum phenylalanine levels a diagnosis of classical phenylketonuria was made, and dietary therapy was started. Urinary pteridine screening for cofactor variants, however, revealed extremely low levels of both neopterin and biopterin. This suggested the possibility of guanosine triphosphate cyclohydrolase I deficiency and led to additional confirmatory assays. Repeat urine, serum, and CSF pteridine profiles, combined with tetrahydrobiopterin-loading studies and the assay of guanosine triphosphate cyclohydrolase I activity in a liver biopsy, confirmed the defect. It is significant to note that the diagnosis was made before the onset of major clinical symptoms. This case illustrates the need for routine cofactor variant screening of all infants in whom hyperphenylalaninemia is diagnosed in the neonatal period.

Oral zinc therapy in the treatment of alpha-mannosidosis.

Human alpha-mannosidosis is a lysosomal storage disorder characterized by mental retardation, dysostosis multiplex, and hepatosplenomegaly. Deficiency of the enzyme leads to accumulation of mannose-rich glycoconjugates in tissues. Zinc sulphate has been shown to stimulate alpha-mannosidase activity in vitro. Oral zinc therapy was attempted on a 4-year-old boy with alpha-mannosidosis for 3 years. After almost 10 years of follow-up on and off zinc therapy, we must conclude that oral zinc does not substantially affect the clinical course of alpha-mannosidosis.

Hepatic dysfunction in Alström disease.

Alström disease is a rare disorder; less than 20 cases have been reported. An 11-year-old girl is described with this condition. She has pigmentary retinopathy, sensory neural deafness, obesity, Type II diabetes mellitus, hyperlipidemia, and acanthosis nigricans. However, in addition she developed hepatic dysfunction, pathologically similar to chronic active hepatitis. This may be a further, previously undescribed systemic manifestation of Alström disease.

Bone marrow harvesting using local anaesthesia and PCA-alfentanil: a feasible alternative to general or regional anaesthesia.

We examined the feasibility of combined use of local anaesthesia (LA) and patient-controlled analgesia with alfentanil (PCA-alfentanil) for bone marrow harvesting (BMH) in 16 consecutive in-patient donors (nine allogeneic and seven autologous). A loading dose of alfentanil 15 micrograms/kg was delivered at the time of skin preparation followed by a background infusion of alfentanil 0.05 microgram/kg/min. On -demand bolus doses of alfentanil were 4 micrograms/kg with lockout intervals of 3 min. Local anaesthesia was achieved using 1% lignocaine (up to 7 mg/kg) with 1:200,000 adrenaline. All donors were mildly sedated during BMH, tolerated the procedure well, and experienced no cardiovascular or respiratory complications. Post-operative nausea and vomiting were the only side-effects. All donors indicated that the combined use of LA with PCA-alfentanil was acceptable for BMH. Our preliminary results suggest that although optimal PCA settings have yet to be determined, this technique may be a feasible and effective alternative for BMH in situations where general or regional anaesthesia is undesirable.

Bone marrow transplantation in Gaucher's disease: effect of mixed chimeric state.

The effective dose and schedule of enzyme replacement therapy for Gaucher's disease have not been definitely established. We report a case of mixed chimeric state in an allogeneic BMT patient and followed her clinical and laboratory progress. The result shows that a low but sustained glucocerebrosidase level may provide symptomatic relief for this lysosomal disorder.

Selective media for isolation of Burkholderia (Pseudomonas) cepacia from the respiratory secretions of patients with cystic fibrosis.

One hundred and six specimens from 90 patients with cystic fibrosis were evaluated for the presence of Burkholderia cepacia using a current routine diagnostic protocol as well as a research protocol involving polymyxin B-MacConkey agar without crystal violet, PC agar, OFPVL agar, and a selective brain-heart infusion broth. Ten specimens from eight patients (8.9%) were positive by any method. The selective enrichment broth was the only medium that yielded B cepacia from all 10 positive samples, although the routine protocol was successful for eight of these. Transient carriage was identified in one patient. Epidemiological studies may be better served by the use of selective enrichment rather than selective solid media alone. Carrier status for B cepacia requires more strict definition if positive carrier status is to be accepted as having medical importance.

Effect of an o-raffinose cross-linked haemoglobin product on oesophageal and lower oesophageal sphincter motor function.

The present experiments evaluate the effects on oesophageal motility of an o-raffinose cross-linked haemoglobin-based oxygen carrier (HBOC) purified from outdated donated human blood cells (HemolinkTM), with attention to dose-response (0.6-2.4 g kg-1), oxygenation status and low molecular weight components (4.4-36.4% 64 kDa or less). In ketamine-anaesthetized cats, lower oesophageal sphincter (LES) function and oesophageal peristalsis were monitored 0.5 h before, during and up to 3.5 h after HBOC infusion, and in some cats at 24 h. (1) All products significantly inhibited LES relaxation and increased peristaltic velocity in the distal smooth muscle oesophagus, without consistently altering resting LES pressure. (2) Effects on peristaltic velocity reached a maximum at the smallest dose, whereas the effects on LES relaxation had a maximum effect at 1.2 g kg-1. (3) Effects were not significantly altered by the haemoglobin oxygenation status or presence of low molecular weight components. (4) Repetitive oesophageal contractions occurred. In the cat, an o-raffinose cross-linked human haemoglobin product produces changes in oesophageal body and LES function, which are independent of the HBOC oxygenation status and composition of the low molecular weight components tested. Changes may persist for at least 24 h. These motility changes are likely due to scavenging of nitric oxide by the haemoglobin.

Review of Metabolic Screening Program of Children's Hospital, Vancouver, British Columbia. 1971--1977.

1. Between 1971 to 1977, 74,521 urines, collected on filter paper and mailed in, were screened by the Metabolic Screening Program of the Children's Hospital. These represented 45.9% of live births in B.C. hospitals were the program has been available. The mean age of the infants was 4.4 weeks. Urines were examined by chromatography with ethyl acetate-pyridine-water for sugars. 1423 (2.13%) had an abnormal pattern necessitating a repeat urine card. A persistent abnormality was noted in 167 (0.22%) and from these a liquid urine sample was obtained for two dimensional amino acid chromatography and/or a repeat sugar chromatography. 2. In 47 (0.06%) of these a definite metabolic abnormality was confirmed. These included cases of Iminoglycinuria (8), Hartnup trait (4), Nonketotic hyperglycinemia (2), Histidinemia (1), Cystathioninuria (5), Argininosuccinic aciduria (1), Maple Syrup Urine Disease (1), Diabetes Mellitus (1), Renal glycosuria (1) and Persistent galactosuria (3). 201 infants had a slight increase of cystine and/or lysine, and 19 of these were documented to be heterozygous for cystinuria.

Observed range of assay values for plasma and cerebrospinal fluid amino acid levels in infants and children aged 3 months to 10 years.

From data collected at the Children's Hospital, Vancouver, during a two year period, 1976 - 1977, we have determined a range of values for children aged 3 months to 6 years for 24 plasma amino acids and for children aged 3 months to 10 years for 18 cerebrospinal fluid amino acids. A total of 26 plasma and 21 cerebrospinal fluid samples were accepted for our reference population. Six of the children in the plasma group were also in the cerebrospinal fluid group, making a total of 39 children in the study.

Biochemical investigation of a child with molybdenum cofactor deficiency.

A girl aged eight months, who presented with developmental delay and dislocated optic lenses, was diagnosed as having combined sulfite oxidase and xanthine dehydrogenase deficiencies consistent with molybdenum cofactor deficiency. The diagnosis was confirmed by demonstrating the absence in urine of urothione, a molybdenum cofactor metabolite. Prenatal diagnosis excluded the disease in the mother's second pregnancy. A summary of an in vitro study of molybdenum cofactor synthesis in the patient is given.

Protease binding by alpha 2 macroglobulin in cystic fibrosis.

The interaction of alpha 2 macroglobulin (alpha 2M) with exogenous proteases has been reported by others to be abnormal in cystic fibrosis (CF). We have re-examined these claims. Four parameters were considered:(1) the molar protease binding of alpha 2M; (2) the interaction of bovine cationic trypsin (BCT), complexed to alpha 2M, with low molecular mass substrate, benzoyl arginine ethyl ester (BAEE); (3) the stability of formed alpha 2 M-BCT complexes; and (4) the subunit structure of alpha 2M. We have found CF alpha 2M to be similar to control alpha 2M in every respect studied.

Effect of a concomitant single dose of ethanol on the hepatotoxicity and metabolism of acetaminophen in mice.

A concomitant single dose of ethanol (1 g/kg) protected mice from hepatic injury induced by acetaminophen (250 mg/kg) as evidenced by the lowering of plasma transaminases. Pharmacokinetic studies with [14C]acetaminophen indicated that ethanol enhanced the initial blood concentrations of radiolabel and its rate of elimination. A tissue distribution study suggested that these effects were probably due to an ethanol-induced inhibition of the biliary clearance of acetaminophen from the blood. Examination of the urinary and biliary metabolites indicated that ethanol inhibited the excretion of the degradation products derived from the glutathione-deactivated hepatotoxic acetaminophen intermediate. The decrease in acetaminophen induced hepatotoxicity was therefore attributed to an inhibitory effect of ethanol on the biotransformation of acetaminophen to the toxic intermediate.

N-acetylcysteine-induced inhibition of gastric emptying: a mechanism affording protection to mice from the hepatotoxicity of concomitantly administered acetaminophen.

Swiss Webster male mice, 22 +/- 3 g, killed 17-18 h following the concomitant oral administration of acetaminophen (350 mg/kg) and N-acetyl-cysteine (NAC, 100-500 mg/kg, treated) had statistically significant lower plasma transaminases (GOT and GPT) than control mice (acetaminophen + water). Possible mechanisms underlying this protective effect of NAC were examined. NAC (500 mg/kg) reduced [14C]acetaminophen-derived radioactivity in the blood and tissues but increased the percentage of the dose in the gastrointestinal tract. Depletion of hepatic sulphydryl compounds below 75% of the control value was prevented by NAC treatment, whereas urinary excretion of mercapturate and sulfate, metabolites derived from sulphydryls, were proportionally increased and excretion of unchanged drug was decreased by NAC. Absorption of acetaminophen from the small intestine was prevented by NAC and this was attributed to an inhibition in gastric emptying. Since all changes observed following NAC treatment could be attributed to inhibition of gastric emptying, it was considered the major mechanism responsible for affording in mice protection from acetaminophen-induced hepatocellular damage following concomitant oral administration.

Treatment of recurrent hemoptysis in a child with cystic fibrosis by repeated bronchial artery embolizations and long-term tranexamic acid.

The course of a 12-year-old girl with cystic fibrosis (CF) and with recurrent hemoptysis since age 8 years is described. Conservative measures failed to control her bleeding. Hemoptysis was only partially controlled by repeated bronchial arterial embolizations. However, the addition of tranexamic acid (TXA) resulted in complete cessation of bleeding. Attempts to withdraw TXA therapy resulted in recurrence of hemoptysis; this patient has, therefore, been continuously maintained on this therapy for the past 4 years. No side effects of long-term TXA treatment have been noted.

Effects of rifampin pretreatment on hepatic parameters in the rabbit.

Rifampin pretreatment in the rabbit caused a selective induction of hepatic parameters resembling in some respects phenobarbital induction. Concomitant with induction, a transient selective inhibition of hepatic parameters was also observed. This two-fold effect of rifampin offers an explanation for the discrepancy surrounding the dosage and species differences in hepatic induction reported in the literature.