The changing prevalence of respiratory symptoms in atopic children in response to air pollution

Following the promotion of anti-air pollution measures in steam power stations using crude oil, atmospheric concentrations of sulphur dioxide, nitrogen dioxide and suspended particulates have declined. These changes in atmospheric concentrations were accompanied by a decline in the prevalence of respiratory symptoms among schoolchildren living near the power stations. In analysing the correlation between air pollutant concentrations and the prevalence of respiratory symptoms, those with positive skin reactions to house dust extract (the positive group) showed a more significant correlation coefficient compared to those who had never had a positive skin reaction (the negative group). In addition, schoolchildren more heavily exposed to air pollutants showed the higher prevalence of respiratory symptoms than the others. With regard to the kind of air pollutants, both sulphur dioxide and nitrogen dioxide were more closely associated with the prevalence of respiratory symptoms than suspended particulates. This study has therefore demonstrated that the positive group is a useful population for monitoring the health effects associated with low-degree air pollution of gaseous agents.     

A novel beta-myosin heavy chain gene mutation, p.Met531Arg, identified in isolated left ventricular non-compaction in humans, results in left ventricular hypertrophy that progresses to dilation in a mouse model

Mutations in the betaMHC (beta-myosin heavy chain), a sarcomeric protein are responsible for hypertrophic and dilated cardiomyopathy. However, the mechanisms whereby distinct mutations in the betaMHC gene cause two kinds of cardiomyopathy are still unclear. In the present study we report a novel betaMHC mutation found in a patient with isolated LVNC [LV (left ventricular) non-compaction] and the phenotype of a mouse mutant model carrying the same mutation. To find the mutation responsible, we searched for genomic mutations in 99 unrelated probands with dilated cardiomyopathy and five probands with isolated LVNC, and identified a p.Met531Arg mutation in betaMHC in a 13-year-old girl with isolated LVNC. Next, we generated six lines of transgenic mice carrying a p.Met532Arg mutant alphaMHC gene, which was identical with the p.Met531Arg mutation in the human betaMHC. Among these, two lines with strong expression of the mutant alphaMHC gene were chosen for further studies. Although they did not exhibit the features characteristic of LVNC, approx. 50% and 70% of transgenic mice in each line displayed LVH (LV hypertrophy) by 2-3 months of age. Furthermore, LVD (LV dilation) developed in approx. 25% of transgenic mice by 18 months of age, demonstrating biphasic changes in LV wall thickness. The present study supports the idea that common mechanisms may be involved in LVH and LVD. The novel mouse model generated can provide important information for the understanding of the pathological processes and aetiology of cardiac dilation in humans.     

Rhabdomyosarcoma in a patient with mosaic Klinefelter syndrome and transformation of immature teratoma

A 27-year-old man was found to have a mediastinal tumour and the histological diagnosis was immature teratoma. Remission was achieved by chemotherapy and total resection. However, he developed anaemia and leukoerythroblastosis after 2 years of remission, and was referred to our hospital. Rhabdomyosarcoma cells were detected in the bone marrow and pleural effusion. Moreover, karyotype analysis of peripheral blood and bone marrow cells revealed mosaic-type Klinefelter syndrome. We diagnosed the case as transformation of teratoma into rhabdomyosarcoma in Klinefelter syndrome. Although intensive chemotherapy was performed, the patient died with meningeal infiltration.     

Plasma concentration of brain natriuretic peptide as a biochemical marker for the evaluation of right ventricular overload and mortality in chronic respiratory disease

The purpose of this study was to evaluate whether the plasma brain natriuretic peptide (BNP) concentration is a useful marker of right ventricular (RV) overload and whether it has prognostic value as a predictor of death in patients with chronic respiratory disease (CRD). We measured the plasma BNP and atrial natriuretic peptide (ANP) concentrations in 31 consecutive patients with CRD who underwent right-heart catheterization to evaluate pulmonary hypertension. All patients were followed for >12 months. The plasma BNP concentration closely correlated with the mean pulmonary artery pressure and pulmonary vascular resistance (r=0.62, P<0.0005 and r=0. 85, P<0.0001), and showed a weak linear correlation with cardiac output (r=-0.36, P<0.05). During the follow-up period, 5 (16%) end-stage CRD deaths (4 RV heart failure and 1 respiratory infection) and 2 non-end-stage CRD deaths occurred. In a stepwise multivariate Cox proportional-hazards regression analysis including age, sex, BNP, ANP, hemodynamic variables and the ratio of PaO(2) to fraction of inspired oxygen, only BNP (P<0.05) was an independent predictor of end-stage CRD death. The upward and leftward shift in the receiver operating characteristic curve between patients with end-stage CRD death and those without was greater for BNP than for ANP. Our findings suggest that the plasma BNP concentration may be an inexpensive, simple and useful marker of RV overload and end-stage CRD death in CRD patients. These preliminary results need to be confirmed in a large series of CRD patients.     

Relationship between cognitive function and regional cerebral blood flow in different types of dementia

Purpose: We assessed relationships between cognitive impairment and regional cerebral blood flow (rCBF) in the different types of dementia.

Subjects and Methods: Subjects, who included 27 with Alzheimer's disease (AD), seven with frontotemporal dementia (FTD), six with vascular dementia (VaD), and 12 normal controls, were evaluated using the Mini-mental State (MMS), Kana-hiroi Test, an auditory verbal learning test (AVLT), a word fluency test (WFT) and Raven's Coloured Progressive Matrices (RCPM). The rCBF was measured using a three-dimensional stereotaxic ROI template method (3DSRT).

Results: In all dementia types, left superior frontal hypoperfusion was demonstrated. In AD and VaD significant CBF reduction also was seen in both angular, temporal, occipital, and precentral, both hippocampi, thalami, and pericallosal regions, and the left lenticular nucleus. MMS, Kana-hiroi Test, and AVLT scores correlated with CBF in all regions. WFT scores were correlated highly with CBF in the left side in frontal, temporal, and angular regions and right and left lenticular nuclei, thalami, and pericallosal regions. RCPM scores correlated with CBF in posterior regions.

Conclusion: Close coupling was evident between reduced rCBF and cognitive dysfunction in patients with dementia. Use of neuropsychologic tests and rCBF determinations in combination should enhance diagnostic accuracy.     

Cerebral Infarction with Pulmonary Thromboembolism Due to Immobilization

Arterial and venous thrombi can coexist without preexisting conditions, such as malignant disease, thrombotic predisposition, or arteriovenous shunt. We herein report a case of acute cerebral infarction and pulmonary thromboembolism in the absence of underlying disease. A 71-year-old woman presented with left hemiplegia. On an examination, her oxygen saturation was 91% on ambient air despite the absence of chest symptoms and clear lung fields on a chest radiograph. The patient was finally diagnosed with acute cerebral infarction caused by large artery atherosclerosis and acute pulmonary thromboembolism due to deep vein thrombosis, consequent to immobilization for three days after the onset of cerebral infarction.