Background: Chronic obstructive pulmonary disease (COPD) is characterised by the presence of airflow limitation caused by loss of lung elasticity and/or airway narrowing. The pathological hallmark of loss of lung elasticity is emphysema, and airway wall remodelling contributes to the airway narrowing. Using CT, these lesions can be assessed by measuring low attenuation areas (LAA) and airway wall thickness/luminal area, respectively. As previously reported, COPD can be divided into airway dominant, emphysema dominant and mixed phenotypes using CT. In this study, it is postulated that a patient's physique may be associated with the relative contribution of these lesions to airflow obstruction. Methods: CT was used to evaluate emphysema and airway dimensions in 201 patients with COPD. Emphysema was evaluated using percentage of LAA voxels (LAA%) and airway lesion was estimated by percentage wall area (WA%). Patients were divided into four phenotypes using LAA% and WA%. Results: Body mass index (BMI) was significantly lower in the higher LAA% phenotype (ie, emphysema dominant and mixed phenotypes). BMI correlated with LAA% (r = 20.557, p,0.0001) but not with WA%. BMI was significantly lower in the emphysema dominant phenotype than in the airway dominant phenotype, while there was no difference in forced expiratory volume in 1 s %predicted between the two. Conclusion: A low BMI is associated with the presence of emphysema, but not with airway wall thickening, in male smokers who have COPD. These results support the concept of different COPD phenotypes and suggest that there may be different systemic manifestations of these phenotypes.Chronic obstructive pulmonary disease (COPD) is characterised by the presence of airflow limitation caused by loss of lung elastic recoil and/or airway narrowing.1 Emphysema is the pathological lesion that correlates most closely with loss of lung elastic recoil, 2 while the airway component is characterised by thickening and narrowing of membranous bronchioles. 3 We have previously reported that the relative contributions of these processes to airflow obstruction in individual patients with COPD can be assessed by measuring low attenuation area (LAA) and airway wall thickness/luminal area using CT.4 5 Dividing patients with COPD into airway dominant, emphysema dominant and mixed phenotypes may aid in the study of the pathogenesis, in the assessment of pharmacological interventions and ultimately in the choice of patient specific therapy. 6 There is increasing evidence that COPD is a systemic illness 7 8 and low body weight is a prominent systemic manifestation. The cachexia associated with COPD was traditionally believed to be more prevalent among those whose airflow limitation was due to predominant emphysema and those who had a relatively maintained ventilatory drive (the ''pink puffer'' hypothesis). 9The ability to make quantitative estimates of the degree of emphysema in individual patients allows a test of the longstanding hypothesis that emphysema predominant patients...
In this study, we determined the complete nucleotide sequence of the mitochondrial genome of the Japanese pond frog Rana nigromaculata. The length of the sequence of the frog was 17,804 bp, though this was not absolute due to length variation caused by differing numbers of repetitive units in the control regions of individual frogs. The gene content, base composition, and codon usage of the Japanese pond frog conformed to those of typical vertebrate patterns. However, the comparison of gene organization between three amphibian species (Rana, Xenopus and caecilian) provided evidence that the gene arrangement of Rana differs by four tRNA gene positions from that of Xenopus or caecilian, a common gene arrangement in vertebrates. These gene rearrangements are presumed to have occurred by the tandem duplication of a gene region followed by multiple deletions of redundant genes. It is probable that the rearrangements start and end at tRNA genes involved in the initial production of a tandemly duplicated gene region. Putative secondary structures for the 22 tRNAs and the origin of the L-strand replication (OL) are described. Evolutionary relationships were estimated from the concatenated sequences of the 12 proteins encoded in the H-strand of mtDNA among 37 vertebrate species. A quartet-puzzling tree showed that three amphibian species form a monophyletic clade and that the caecilian is a sister group of the monophyletic Anura.
BackgroundHealth status, dyspnea and psychological status are important clinical outcomes in chronic obstructive pulmonary disease (COPD). However, forced expiratory volume in one second (FEV1) measured by spirometry, the standard measurement of airflow limitation, has only a weak relationship with these outcomes in COPD. Recently, in addition to spirometry, impulse oscillometry (IOS) measuring lung resistance (R) and reactance (X) is increasingly being used to assess pulmonary functional impairment.MethodsWe aimed to identify relationships between IOS measurements and patient-reported outcomes in 65 outpatients with stable COPD. We performed pulmonary function testing, IOS, high-resolution computed tomography (CT), and assessment of health status using the St. George's Respiratory Questionnaire (SGRQ), dyspnea using the Medical Research Council (MRC) scale and psychological status using the Hospital Anxiety and Depression Scale (HADS). We then investigated the relationships between these parameters. For the IOS measurements, we used lung resistance at 5 and 20 Hz (R5 and R20, respectively) and reactance at 5 Hz (X5). Because R5 and R20 are regarded as reflecting total and proximal airway resistance, respectively, the fall in resistance from R5 to R20 (R5-R20) was used as a surrogate for the resistance of peripheral airways. X5 was also considered to represent peripheral airway abnormalities.ResultsR5-R20 and X5 were significantly correlated with the SGRQ and the MRC. These correlation coefficients were greater than when using other objective measurements of pulmonary function, R20 on the IOS and CT instead of R5-R20 and X5. Multiple regression analyses showed that R5-R20 or X5 most significantly accounted for the SGRQ and MRC scores.ConclusionsIOS measurements, especially indices of peripheral airway function, are significantly correlated with health status and dyspnea in patients with COPD. Therefore, in addition to its simplicity and non-invasiveness, IOS may be a useful clinical tool not only for detecting pulmonary functional impairment, but also to some extent at least estimating the patient's quality of daily life and well-being.
The toads of the Bufo bufo species group are widely distributed in the Eurasian continent and Japanese Archipelago. In this study, we analyzed the mtDNA gene sequences of this species group and estimated the divergence time to clarify the evolutionary relationships and biogeography of toads distributed in the Far East and Europe. The phylogenetic tree indicated that this group produced Bufo bufo in Europe, whereas it produced B. japonicus in the Far East. B. japonicus was divided into three major clades corresponding to a group consisting of B. j. gargarizans in China, B. j. bankorensis in Taiwan, and B. j. miyakonis on Miyako Isl. and eastern and western groups of Japanese B. j. japonicus subspecies group. The eastern and western groups were divided into several subclades which tended to reflect the region-specific geographic distribution of all localities except B. j. japonicus from Hakodate. The estimated branching times of these clades suggest that geological events may have influenced the divergence of the toads distributed in the Far East and Europe.
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