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Introduction: The purpose of this prospective study is to determine the effects of a pulmonary rehabilitation programme (PRP) conducted at our centre for patients with chronic lung disease., Materials and Methods: Thirty-four patients (27 men and 7 women, mean age 67.7 years) with predominantly moderate-to-severe chronic obstructive pulmonary disease (31 patients), bronchiectasis (2 patients) and interstitial lung disease (1 patient) completed a 6-week outpatient PRP that included education, physical and respiratory care instruction and supervised exercise training. Outcome assessment was performed at baseline, on completion of PRP and 3 months after PRP. Physiologic measures included pulmonary function, incremental exercise and 6-minute walk tests (6MWTs). Disease-specific quality of life was assessed using the Chronic Respiratory Disease Questionnaire (CRDQ)., Results: There was no significant change in resting spirometry or lung volumes after PRP. Maximal oxygen uptake and work-rate improved significantly after PRP by 132.4 mL kg-1 min-1 and 10.7 W, respectively. 6MWT distance improved significantly by a mean of 67.3 m (P < 0.0001). Maximum Borg dyspnoea scores decreased significantly by 1.2 +/- 0.5 (P < 0.038). All domains of the CRDQ completed by a sub-group of patients improved significantly and the total scores increased by a mean of 21.7 points at the end of the PRP. The improvements gained in maximal exercise capacity immediately following PRP were maintained in 17 patients who returned for repeat assessment 3 months after PRP., Conclusion: Patients who completed a comprehensive PRP at our centre showed significant increase in functional capacity, reduction of exertional dyspnoea and improvement in health status.

Pulmonary metastases from choriocarcinoma can very rarely give rise to a 'miliary' pattern on the chest X-ray. A 23-year-old woman with a diffuse nodular pattern on chest X-ray died due to acute respiratory failure and cor pulmonale. At autopsy, choriocarcinoma of the uterus was found. In the lungs, multiple macrovascular tumour emboli within branches of pulmonary muscular arteries in the region of segmental/subsegmental bronchi were detected. There was no evidence of pulmonary parenchymal metastases, pneumonia or tuberculosis. The 'miliary' pattern of pulmonary metastases described in cases of choriocarcinoma may be due to large vessel intra-arterial tumour emboli rather than disseminated parenchymal metastases.

Introduction: Accurate assessment of the exercise capacity of patients with chronic obstructive pulmonary disease (COPD) is important for the dual purpose of exercise prescription and determining response to therapy. Currently, the clinical utility of cardiopulmonary exercise testing (CPET) of patients with COPD as part of their evaluation for pulmonary rehabilitation is not established. The aims of this study were to evaluate the role of CPET in determining maximal exercise capacity and the causes of exercise limitation in patients with COPD., Materials and Methods: The results of resting pulmonary function tests and CPET performed on 33 subjects with stable COPD as part of their evaluation for pulmonary rehabilitation were reviewed. Thirty-two of these patients had moderate or severe COPD., Results: Twenty-nine of the 33 patients were able to perform maximal exercise tests during CPET. Of these 29 maximal tests, the causes of exercise limitation were ventilatory limitation in 17 patients, significant oxygen desaturation in 1 patient and both ventilatory limitation and oxygen desaturation in 11 patients. Limb muscle dysfunction is a possible limiting factor in the 4 patients with sub-maximal tests. Physical deconditioning may be a contributory factor of exercise intolerance in 2 patients. Although there was significant correlation (r = 0.597, P = 0.01) between peak VO2 percent predicted and FEV1 percent predicted, there was marked variability of peak VO2 for a given degree of airflow obstruction., Conclusions: CPET is useful for determining the causes of exercise limitation and for assessing the maximal exercise capacity of patients with COPD.

In our previous study, we found that myricetin, a naturally occurring bioflavonoid, was able to stimulate glucose transport in rat adipocytes and enhance insulin-stimulated lipogenesis. We report here that after 2 days of treatment with myricetin (3 mg/12 h), hyperglycemia in diabetic rats was reduced by 50% and the hypertriglyceridemia that is often associated with diabetes was normalised. Treatment with myricetin increased hepatic glycogen and glucose-6-phosphate content. It increased hepatic glycogen synthase I activity without having any effect on total glycogen synthase nor phosphorylase a activity. It lowered phosphorylase a activity in the muscle. Thus, the hypoglycemic effect of myricetin is likely to be due to its effect on glycogen metabolism. There was no indication of serious hepatotoxicity with myricetin treatment and therefore, myricetin could be of therapeutic potential in diabetes.

Introduction: We evaluated the results of patients with congestive heart failure (CHF) who underwent cardiopulmonary exercise testing (CPET) as part of their assessment for heart transplantation in order to examine the relationship between exercise capacity and resting indices of left ventricular function in these patients., Materials and Methods: Twenty-seven ambulatory heart transplant candidates underwent CPET using a cycle ergometer and an incremental work-rate protocol till symptom-limitation. These patients included 24 men and 3 women with a mean age of 42.3 years. The aetiology of CHF was coronary artery disease in 14 patients, dilated cardiomyopathy in 11 patients, and congenital heart disease in 2 patients. Mean resting left ventricular ejection fraction (LVEF) was 19% (range 7% to 36%)., Results: Thirteen of the 27 tests performed were maximal studies and all except 2 subjects attained a measurable anaerobic threshold during CPET. Of the 13 maximal tests, the causes of exercise limitation were cardiomyopathy in 3 patients, ischaemic heart disease in 2 patients, significant oxygen desaturation in 2 patients, ventilatory limitation due to obstructive lung disease in 1 patient, ventilatory limitation secondary to a restrictive lung disease in 3 patients, and combined obstructive ventilatory and cardiovascular limitation in 2 patients. There was no significant correlation between resting LVEF and peak VO2 percent predicted (r = 0.14, P = 0.49)., Conclusions: Exercise intolerance in patients with CHF may not be related to limited cardiac reserve and non-cardiac causes of exertional symptoms should also be considered. CPET is useful for the evaluation of functional capacity and mechanisms of exercise intolerance in patients with CHF.

Objective: Differing success rates of various pleurodesis agents have been reported in the management of malignant pleural effusions. A randomized clinical trial was conducted to compare the efficacy of two commonly used agents, talc and bleomycin, for the pleurodesis of malignant pleural effusions., Methodology: Inclusion in the study required proof of a malignant pleural effusion by fluid cytology or pleural biopsy. Exclusion criteria included trapped lung, loculated effusions, recurrent effusions and life expectancy < 1 month. Five grams of talc or 1 unit per kilogram bodyweight of bleomycin mixed in 150 mL of normal saline was administered via tube thoracostomy after complete drainage of the pleural effusion in each patient. Treatment success was defined as the absence of recurrent pleural effusion on the chest radiograph 1 month after pleurodesis., Results: Treatment success was achieved in 16 out of 18 patients (89%) in the talc slurry group versus 14 out of 20 patients (70%) in the bleomycin group (P=0.168). Fever and pain were the only side-effects of pleurodesis in both groups., Conclusion: These results indicate that talc slurry is as effective as bleomycin in preventing early recurrence of malignant pleural effusions. Pleurodesis with talc instead of bleomycin can result in significant cost savings.

Introduction: Patients with the upper airway resistance syndrome are frequently overlooked, and even if clinically suspected, often escape identification by polysomnographic monitoring., Clinical Picture: Three cases (2 women and a man) with excessive daytime sleepiness and fatigue were confirmed to have the upper airway resistance syndrome after undergoing polysomnography with oesophageal pressure monitoring., Treatment: Nasal CPAP during sleep was prescribed for 2 cases but 1 case refused all available treatment options., Outcome: After one month of CPAP therapy, the 2 cases reported improved symptoms and Epworth sleepiness scores. Lower daytime blood pressures were also recorded., Conclusions: Oesophageal pressure monitoring and EEG arousal analysis can greatly enhance the diagnostic accuracy in the upper airway resistance syndrome. Accurate diagnosis and effective treatment of this condition is important because of its sequelae of hypersomnolence and association with other disorders like systemic hypertension.

Introduction: Lung volume reduction surgery (LVRS) and pulmonary rehabilitation are newer options available in the treatment of advanced emphysema. We describe the progress of our first local patient to have undergone these 2 new treatment modalities., Clinical Picture: A 65-year-old man with advanced emphysema, limited by crippling dyspnoea despite maximal medical therapy with inhaled bronchodilator therapy, methylxanthines and supplementary oxygen., Treatment: Physical reconditioning with a 4-week inpatient pulmonary rehabilitation programme, followed by LVRS and a further 6-week outpatient pulmonary rehabilitation., Outcome: Dramatic improvements in spirometric indices, arterial blood gases, exercise capacity and overall functional status. Improvements maintained at one-year follow up period., Conclusions: LVRS with pulmonary rehabilitation is an exciting new treatment option in a select group of patients with advanced emphysema. Their role in improving overall performance status and quality of life should be considered in patients otherwise considered to have reached the limits of medical therapy.

Background: The development of a pleural effusion in a patient with a known malignancy often raises the possibility that the effusion is due to malignant involvement of the pleura. Accurate diagnosis of the cause of the pleural effusion in such a patient is essential as the treatment and prognosis may vary. Currently, thoracentesis and cytologic analysis of pleural fluid cytology is usually the initial diagnostic step., Aim: To assess the diagnostic yield of pleural fluid cytologic examination in patients with suspected malignant pleural effusions seen at our centre., Methods: Retrospective review of the results of pleural fluid cytologic examination performed on 103 patients who presented with suspected malignant pleural effusions., Results: The underlying malignancies in these patients were as follows: bronchogenic carcinoma (51.5%), breast carcinoma (29.1%), hepatocellular carcinoma (1.9%), carcinoma of the stomach (1.9%), malignant mesothelioma, nasopharyngeal carcinoma, renal cell carcinoma, carcinoma of the oesophagus, lymphoma, carcinoma of the colon (1% each), unknown (9.7%). Initial pleural fluid cytology was positive for malignancy in 48.5% of patients. The yield of this diagnostic procedure was improved with repeated pleural fluid cytologic specimens and when combined with a percutaneous pleural biopsy. There was no statistically significant difference in the clinical features and pleural fluid characteristics of patients with malignant pleural effusions and those in whom the pleural effusions were paramalignant., Conclusion: Pleural fluid cytologic examination is a useful initial step in the diagnostic work-up of patients with suspected malignant pleural effusions. The diagnostic yield of such examination is improved with repeated pleural fluid cytologic specimens and when combined with a percutaneous pleural biopsy. Clinical presentation and pleural fluid characteristics were inadequate in differentiating between malignant and paramalignant effusions.

Race can be considered a risk factor for sleep-disordered breathing (SDB), with higher prevalences and greater severity of the disorder documented among persons of certain racial groups compared with others. Based on clinical observation, it was hypothesized that, other risk factors being equal, Asian patients with SDB have greater severity of their illness compared to Caucasian patients. A cross-sectional study was conducted at a sleep disorders clinic involving 105 Asian patients diagnosed as having SDB after undergoing polysomnography and 99 similarly diagnosed Caucasian patients matched for the following variables: age, gender and body mass index (BMI). The main outcome measure of interest was objective assessment of severity based on polysomnographic data of respiratory disturbance index (RDI) and minimum oxygen saturation (SaO2) during sleep. Symptom scores between patients of the two racial groups were also compared. There were significantly larger proportions of Asians compared to Caucasians with severe obstructive sleep apnea (OSAS) as defined by respiratory disturbance index (RDI) > or = 50 (25.0% vs 11.1%; P = 0.0288) or minimum oxygen saturation (SaO2) < or = 69% (20.6% vs 4.2%; P = 0.0113). The mean minimum SaO2 was significantly lower (P = 0.0001) while the mean (log transformed) esophageal pressure (Pes) value was significantly higher (P = 0.0090) in the Asian group. Logistic regression analysis showed that race was associated with severe SDB (RDI > or = 50) independent of age, sex and BMI. The estimated odds ratio for Asians having severe OSAS compared with Caucasians was 2.51 [95% Confidence Interval (CI) 0.98-6.64]. There was no significant difference in the severity of questionnaire-based symptoms of snoring, apneas during sleep and the median Epworth scores between Asian and Caucasian patients. Based on objective polysomnographic results, Asian patients with OSAS have greater severity of their illness compared to Caucasian patients matched for age, gender and BMI. There was, however, no significant difference in severity of questionnaire-based symptoms between Asian and Caucasian patients with SDB.

1. Myricetin is a natural bioflavonoid whose occurrence in nature is widespread among plants. 2. It has been demonstrated to possess both antioxidative properties and prooxidative properties. 3. It is a potent anticarcinogen and antimutagen, although it has been shown to promote mutagenesis with the use of the Ames Test. 4. Its therapeutic potential and benefits in cardiovascular diseases and diabetes mellitus also are reviewed.

The main advantage of noninvasive ventilation over conventional mechanical ventilation is in the avoidance of endotracheal intubation and its related complications. Currently, the role of noninvasive ventilation in the management of patients with acute respiratory failure is still not firmly established. We conducted a prospective study to evaluate the efficacy of nasal positive pressure ventilation in patients with acute respiratory failure. Thirty-three consecutive patients with acute failure in whom intubation and mechanical ventilation were strongly considered were included in the study. They received ventilatory support by means of BiPAP ventilatory support system and nasal mask. Physical findings and laboratory measurements were documented before and at specific intervals after initiation of support. Eighty per cent (24/30) of patients were successfully supported. Successfully supported patients tolerated the device with improved gas exchange, hence avoiding endotracheal intubation. The mean duration of support was 19.2 hours. There were major associated complications, e.g. gastric distention or aspiration.

The ideal position of the endotracheal tube (ETT) within the trachea is 5 +/- 2 cm from the carina with the head and neck in neutral position (Goodman's criteria). We assessed the possibility of achieving ideal placement of ETTs in our population by positioning them at reference marks of 23 cm in men and 21 cm in women. From January 1995 to April 1995, 105 intubated patients in the Medical Intensive Care Unit, Singapore General Hospital were studied. The mean distance of the ETT tip from the carina was 4.02 cm +/- 3.90. The ETT tip was < 3 cm from the carina in 30 cases (28.6%) with one case resulting in endobronchial intubation. These 30 patients were significantly shorter in height when compared to the rest of the study population (P = 0.01). Five cases (4.8%) had ETT tip > 7 cm from the carina. Adopting the above-mentioned reference marks did not result in ideal positioning of ETTs in a significant proportion of cases (33.4%). We postulate that this is because our Asian population is generally shorter than those in previous studies which had achieved ideal ETT positioning using similar reference marks.

Myricetin is a naturally occurring flavonol that is commonly found in tea, berries, fruits, and medicinal plants. It mimics insulin in stimulating lipogenesis and glucose transport in rat adipocytes in vitro. It was found to stimulate lipogenesis in rat adipocytes and enhance the stimulatory effect of insulin. The EC50 was estimated to be about 65 microM. Myricetin did not have any effect on insulin receptor autophosphorylation nor on the tyrosine kinase activity of the receptor. However, myricetin stimulated both D-glucose and D-3-O-methylglucose uptake in rat adipocytes. The Vmax of glucose transport was increased, but the Km did not change significantly. Immunoblot analysis of Glut4 in rat adipocyte plasma membrane showed that the stimulation of glucose transport was not a consequence of glucose transporter translocation. Instead, the stimulation in glucose uptake probably was due to a change in the intrinsic activity of the glucose transporter possibly caused by alterations in membrane fluidity or transporter-lipid interactions as a result of the insertion of myricetin into the membrane bilayer. Thus, myricetin may have therapeutic potential in the management of non-insulin-dependent diabetes mellitus by stimulating glucose uptake without the presence of fully functional insulin receptor.

Because radiation loss associated with a radiofrequency (RF) coil increases as roughly the fourth power of the frequency, this loss mechanism may become important in high-field studies above 2.0 T. In this study, the contribution of radiation losses at 4.0 T were determined in a rectangular surface coil using an RF shield to modify the radiation losses. The effect of this shield was determined on coil Q, B1 distribution, and signal to noise as a function of distance between the coil and the shield. Phantoms and human tissue were evaluated to characterize the loss mechanisms. The results demonstrate a large radiation loss in the unshielded surface coil. However, the radiation losses in vivo were not dominant owing to a large inductive loss occurring from dielectric currents in the body at 170 MHz.

Major changes have occurred in the epidemiology of community-acquired pneumonia recently. The emergence of new pathogens emphasises the need for continued vigilance in the diagnosis of pneumonia while changes in the microorganism or in the host have resulted in exciting new aspects of several old pathogens. Clinical and radiologic signs are unreliable in predicting the infecting organisms. Thus initial therapy is nearly always empiric. This approach often requires good clinical judgement and a knowledge of local epidemiological patterns in choosing an appropriate regimen. State-of-the-art invasive diagnostic procedures are usually reserved for pneumoniae that fail to resolve with initial treatment. Non-specific measures like stabilisation of underlying medical conditions, adequate nutrition and cessation of smoking or alcohol may help prevent the development of community-acquired pneumonia. On a larger scale, influenza and pneumococcal vaccinations are cost-effective preventive measures.

Tannins occur naturally in relatively abundant amounts in fruits, herbal medicines and common beverages. Thus an understanding of how these polyphenols affect peptide hormone action is of importance. We report here that tannic acid (a hydrolysable tannin) inhibits insulin-stimulated lipogenesis in rat adipose tissue in vitro, with an IC50 estimated to be about 350 microM. However, its monomer, gallic acid, did not show a similar inhibitory effect at concentrations up to 1 mM. The inhibition by tannic acid was less evident with higher concentrations of bovine serum albumin in the incubation buffer. This was attributed to the formation of a tannin-protein complex between bovine serum albumin and tannic acid. In a binding assay, it was observed that the specific binding of insulin to its receptor was not inhibited by tannic acid in the concentration range 0-200 microM. However, insulin-stimulated autophosphorylation of the insulin receptor, and receptor-associated tyrosine kinase phosphorylation of RR-SRC peptide, were inhibited by tannic acid at concentrations as low as 25 microM. Our data do not support the current speculation that tannins affect the activity of peptide hormones by binding to them. Therefore, our finding opens up a new perspective in the understanding of the mode of action of tannins on such hormones.