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.

RACK-1 overexpression protects against goniothalamin-induced cell death.

Goniothalamin, a styryllactone, has been shown to induce cytotoxicity via apoptosis in several tumor cell lines. In this study, we have examined the potential role of several genes, which were stably transfected into T-cell lines and which regulate apoptosis in different ways, on goniothalamin-induced cell death. Overexpression of full-length receptor for activated protein C-kinase 1 (RACK-1) and pc3n3, which up-regulates endogenous RACK-1, in both Jurkat and W7.2 T cells resulted in inhibition of goniothalamin-induced cell death as assessed by MTT and clonogenic assays. However, overexpression of rFau (antisense sequence to Finkel-Biskis-Reilly murine sarcoma virus-associated ubiquitously expressed gene) in W7.2 cells did not confer resistance to goniothalamin-induced cell death. Etoposide, a clinically used cytotoxic agent, was equipotent in causing cytotoxicity in all the stable transfectants. Assessment of DNA damage by Comet assay revealed goniothalamin-induced DNA strand breaks as early as 1 h in vector control but this effect was inhibited in RACK-1 and pc3n3 stably transfected W7.2 cells. This data demonstrate that RACK-1 plays a crucial role in regulating cell death signalling pathways induced by goniothalamin.

Numerical modeling of exhaled droplet nuclei dispersion and mixing in indoor environments.

The increasing incidence of indoor airborne infections has prompted attention upon the investigation of expiratory droplet dispersion and transport in built environments. In this study, a source (i.e. a patient who generates droplets) and a receiver (i.e. a susceptible object other than the source) are modeled in a mechanically ventilated room. The receiver's exposure to the droplet nuclei is analyzed under two orientations relative to the source. Two droplet nuclei, 0.1 and 10 microm, with different emission velocities, are selected to represent large expiratory droplets which can still be inhaled into the human respiratory tracts. The droplet dispersion and mixing characteristics under well-mixed and displacement ventilation schemes are evaluated and compared numerically. Results show that the droplet dispersion and mixing under displacement ventilation is consistently poorer. Very low concentration regions are also observed in the displacement scheme. For both ventilation schemes, the intake dose will be reduced substantially if the droplets are emitted under the face-to-wall orientation rather than the face-to-face orientation. Implications of using engineering strategies for reducing exposure are briefly discussed.

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.

Lessons learned from initial experience with peritonectomy and intra-peritoneal chemotherapy infusion.

INTRODUCTION: Patients diagnosed with peritoneal carcinomatous usually survive for less than 6 months. Cytoreductive surgery allows relief of the obstruction and improvement in functional status, while intraperitoneal chemotherapy infusion provides high local concentrations of chemotherapeutic agents. Our institutional experience is reviewed to assess the selection criteria, peri-operative complications, and outcomes. MATERIALS AND METHODS: We carried out a retrospective review of nine patients who had undergone aggressive cytoreductive surgery and hyperthermic intra- and early post-operative chemotherapy by a single surgeon between April 2000 and October 2004. The inclusion criteria were: (1) a demonstrated absence of extra-peritoneal and hepatic spread, (2) fitness of the patient and ability to tolerate cytoreductive surgery and intra-operative chemotherapy, and (3) the presence of a primary tumor originating form the gastro-intestinal tract (colonic, appendiceal, and gastric primaries). RESULTS: Seven women and two men, with a median age of 55 years, were treated. The median duration of the operation was 12 hours and 55 minutes. Seven of the nine patients required the insertion of at least one chest tube. All patients were monitored in the surgical intensive care unit (SICU) for a median of 1 day, started on feeds after a median of 6 days, and were hospitalized for a median of 16 days (range:11-18 days). There was no peri-operative mortality and only one major peri-operative complication (11.1%). At the time of analysis, the median follow-up was 16 months (range: 2-40 months), and the median disease-free survival was 8 months, with four of the nine patients showing no evidence of recurrence. To date, all of the patients are still alive. A 1-year survival rate of 100% is also documented. CONCLUSIONS: This article describes our initial experience with peritonectomy and intra-operative, intra-peritoneal chemotherapy infusion. Our initial problems included difficulty with leakage of the chemotherapeutic agents into the thoracic cavity that had to be overcome by the early insertion of chest-tubes. With appropriate patient selection, cytoreductive surgery with the infusion of intra-operative chemotherapy can be considered to be a therapeutic option for some patients with diffuse peritoneal metastases, and good disease-free and overall survival can be achieved with minimal morbidity.

Carnitine transporter defect due to a novel mutation in the SLC22A5 gene presenting with peripheral neuropathy.

The carnitine transporter defect (McKusick 212140) is an autosomal recessive disorder caused by mutations in the SLC22A5 gene, which encodes the high-affinity carnitine transporter OCTN2 (Wang et al 2001). Diagnosis is suspected when plasma carnitine levels are extremely low and secondary causes of carnitine loss are excluded. The disease can present with recurrent Reye-like episodes of hypoketotic hypoglycaemia or with cardiomyopathy associated with myopathy (Stanley et al 1991). Here we report novel clinical findings in a 3-year-old with primary carnitine deficiency.

Patient-controlled epidural analgesia after thoracic and upper abdominal surgery using sufentanil with and without bupivacaine 0.125%.

BACKGROUND: Epidural sufentanil can relieve postoperative pain after thoracic and upper abdominal surgery but it has some unwanted side effects. Patient-controlled epidural analgesia (PCEA) allows patients to titrate and reduce their analgesic requirements. OBJECTIVE: The study aims to assess the use of demand-only PCEA after thoracotomy and upper abdominal surgery using sufentanil with or without bupivacaine in terms of pain control, amount of analgesic required and side effect profile. METHODS: After the Hospital Ethics Committee approval and written informed consent, 34 ASA I and II patients were enrolled in this prospective, randomised, double-blinded controlled study. Post-operatively, after achieving adequate analgesia in the recovery, the patients were randomised to receive either sufentanil 1 microg/ml in normal saline (Group S) or sufentanil 1 microg/ml with bupivacaine 0.125% (Group SB) in a demand-only PCEA programme. Pain scores, side effects and amount of analgesia used were reviewed every hour. RESULTS: The demographic profile of both groups was similar. The amount of sufentanil used was higher in Group S than in Group SB but it was not statistically significant. The numbers of patients with high pain scores at rest and during movement were not significantly different between the two groups. The side effect profiles of both groups were similar. CONCLUSIONS: The PCEA demand-only programme using sufentanil 1 microg/ml with and without bupivacaine 0.125% was satisfactory after thoracotomy and upper abdominal surgery in our patient population. The addition of bupivacaine to sufentanil did not significantly reduce the amount of sufentanil required, the pain scores or the side effects.

Infection with Burkholderia cepacia complex genomovars in patients with cystic fibrosis: virulent transmissible strains of genomovar III can replace Burkholderia multivorans.

Infection with Burkholderia cepacia complex in patients with cystic fibrosis (CF) results in highly variable clinical outcomes. The purpose of this study was to determine if there are genomovar-specific disparities in transmission and disease severity. B. cepacia complex was recovered from 62 patients with CF on > or =1 occasions (genomovar III, 46 patients; genomovar II [B. multivorans], 19 patients; genomovar IV [B. stabilis], 1 patient; genomovar V [B. vietnamiensis], 1 patient; and an unclassified B. cepacia complex strain, 1 patient). Patient-to-patient spread was observed with B. cepacia genomovar III, but not with B. multivorans. Genomovar III strains replaced B. multivorans in 6 patients. Genomovar III strains were also associated with a poor clinical course and high mortality. Infection control practices should be designed with knowledge about B. cepacia complex genomovar status; patients infected with transmissible genomovar III strains should not be cohorted with patients infected with B. multivorans and other B. cepacia genomovars.

Long-term comparative trial of positive expiratory pressure versus oscillating positive expiratory pressure (flutter) physiotherapy in the treatment of cystic fibrosis.

OBJECTIVE: The objective was to evaluate the long-term effects of physiotherapy with an oscillating positive pressure device ("flutter") compared with physiotherapy with the use of a positive expiratory pressure (PEP) mask in patients with cystic fibrosis (CF). STUDY DESIGN: Forty children with CF were randomly assigned to performing physiotherapy with the PEP mask or the flutter device for 1 year. Clinical status, pulmonary function, and compliance were measured at regular intervals throughout the study. RESULTS: The flutter group demonstrated a greater mean annual rate of decline in forced vital capacity compared with the PEP group (-8.62 +/- 15.5 vs 0.06 +/- 7.9; P =.05) with a similar trend in forced expiratory volume in 1 second (-10.95 +/- 19.96 vs -1.24 +/- 9.9; P =.08). There was a significant decline in Huang scores (P =.05), increased hospitalizations (18 vs 5; P =.03), and antibiotic use in the flutter group. CONCLUSION: Flutter was not as effective in maintaining pulmonary function in this group of patients with CF compared with PEP and was more costly because of the increased number of hospitalizations and antibiotic use.

An unusual presentation of doxycycline-induced photosensitivity.

Photoonycholysis in association with a generalized phototoxic reaction or as an isolated event is a well-recognized complication of the tetracycline group of antibiotics. We describe a 14-year-old white girl with cystic fibrosis who developed photoonycholysis of all 20 nails while receiving treatment with doxycycline. Pediatricians who prescribe tetracyclines should be aware of this potential complication.

Haemodynamic response following a 10% topload infusion of HemolinkTM in conscious, anaesthetized and treated spontaneously hypertensive rats.

HemolinkTM (HLK), a haemoglobin-based oxygen carrier (HBOC), is currently undergoing Phase II/III clinical trials in surgical patients. It causes some blood pressure rise in animal and human tests. This study was designed to investigate the systemic haemodynamic response to HemolinkTM in spontaneously hypertensive rats (SHR rats). Conscious or anaesthetized SHR rats and control Wistar Kyoto rats (WKY rats) received either HemolinkTM or homologous plasma as a 10% topload infusion. Some awake animals were pretreated with nifedipine and followed by HLK infusion. In the conscious animal study, HLK induced a greater pressure rise and less bradycardia in SHR rats than in WKY rats. In the anaesthetized animal experiment, HLK-induced pressure rise and bradycardia were similar in both strains and less pronounced than in the conscious animals. In the nifedipine pretreated SHR rats, HLK-induced pressure rise was significantly smaller than that observed in nontreated SHR rats and was not different from that of nontreated WKY rats. The HLK-induced bradycardia was significantly smaller in nifedipine-treated animals than in the nontreated SHR or WKY rats. This study suggests that the pressor effect of HemolinkTM can be attenuated in hypertensive animals with general anaesthesia or treatment with antihypertensive agents.

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.

Hemolink-induced effects on intestinal motor function and attenuation of these effects by selected agents.

Hemolink, an oxidized, ring-opened raffinose-crosslinked hemoglobin-based oxygen carrier produced by Hemosol Inc., stimulates esophageal peristalsis, possibly by interference with neural NO-mediated effects. The effects of Hemolink on jejunal tone and contractions, arterial pressure and heart rate were measured in anesthetized rats, and the effect of selected agents in attenuating or reversing these effects was studied. Infusion of L-NAME was used to validate the study model; it caused an immediate increase in tone and initiated phasic contractions indicating that the model was responsive to NO-mediated effects. Hemolink administration caused effects on intestinal motor function similar to those caused by L-NAME, including increases in basal tone and contraction amplitude. Rat whole blood caused none of these changes. The Hemolink-induced effects were less immediate in some animals compared to those observed after L-NAME. As well there was greater inter-animal variability on the effects. Hemolink administration also caused a mild increase in arterial blood pressure and a reciprocal decrease in heart rate in some animals. Co-administration of morphine, a common analgesic that has been reported to influence the motility of the GI tract; L-arginine, a substrate for NO synthesis; and glycopyrrolate, an anti-cholinergic agent, did not significantly modulate the Hemolink effects, whereas nitroglycerin, an NO donor; and nifedipine, a slow calcium-channel blocker, attenuated or reversed these effects.

Long-term comparative trial of conventional postural drainage and percussion versus positive expiratory pressure physiotherapy in the treatment of cystic fibrosis.

OBJECTIVE: We report the results of a long-term comparative trial of physiotherapy by the positive expiratory pressure (PEP) technique with a PEP mask (Astra Meditec) versus conventional postural drainage and percussion (PD&P). Forty patients, ages 6 to 17 years, with Shwachman scores between 52 and 93, attending the cystic fibrosis clinic were enrolled in the study and randomly assigned to one of two groups. Group A (control) continued to perform physiotherapy by using PD&P for a 1-year period, whereas patients assigned to group B performed physiotherapy with the PEP technique for the same period. Compliance with physiotherapy was closely monitored for both groups throughout the study. Clinical status and pulmonary function (forced vital capacity [FVC], FEV1, and FEF25-75) were measured at 3-month intervals. Group B (PEP) demonstrated improved pulmonary function in all parameters as measured by change in percent predicted value for age, gender, and height. The changes in pulmonary function over the study period were: FVC, +6.57; FEV1, +5.98; and FEF25-75, +3.32. This improvement was significantly different from that of group A (PD&P) whose pulmonary function declined in all parameters (FVC, -2.17; FEV1, -2.28; FEF25-75, -0.24). The differences between treatment groups were statistically significant for the changes in FVC (p = 0.02) and FEV(1) (p = 0.04). Our results indicate that for our patients with cystic fibrosis, pulmonary physiotherapy with the PEP technique was superior to conventional physiotherapy with the PD&P technique.

A two-year experience of an acute pain service in Singapore.

The first anaesthesia-based acute pain service in Singapore is described. The benefits, risks and resource implications of such a service during its first two years are reviewed. One thousand two hundred and sixty-eight (1,268) post-operative patients were treated with either patient-controlled analgesia (310 patients) or epidural opioid analgesia (958 patients). Retrospective analysis of the data revealed good patient satisfaction with a low incidence of potentially life threatening side-effects: more than 79% of patients reported satisfaction with pain control while only 0.2% of patients receiving epidural opioid analgesia experienced clinically significant respiratory depression. There were no reports of respiratory depression in the patient-controlled analgesia group. The authors conclude that the provision of an acute pain service in the local context was safe and resulted in excellent post-operative patient satisfaction.

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.

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.

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.

Chronic tobacco smoking and gender as variables affecting amantadine disposition in healthy subjects.

Amantadine HCl (3 mg kg-1) was administered orally to 20 young healthy adults. Its apparent volume of distribution (V2/F) was higher in smokers than nonsmokers, 6.05 +/- 0.86 vs 4.87 +/- 0.85 l kg-1; (mean +/- s.d., 10/group, P < 0.011), and no gender-associated effect was observed. Renal clearance did not vary with time-interval, but urinary recovery at 48 h was higher in men than in women (60.2 +/- 7.5% vs 47.0 +/- 15.0%, P < 0.032). Males had higher renal clearances than females when normalised for body mass index (BMI, 0.492 +/- 0.284 vs 0.248 +/- 0.137 l-1 BMI h-1, (10/group, P < 0.032)). On combining data from a previous study, the weight normalised renal clearance was also higher in men than in women, 0.160 +/- 0.075 vs 0.102 +/- 0.053 l kg-1 h-1 (19/group, P < 0.01). Chronic tobacco smoking did not alter the plasma or renal amantadine clearance. We conclude that gender and tobacco smoking are independent variables effecting amantadine disposition.