Measurement of diffusing capacity by the intrabreath method]

The diffusing capacity of the lung for carbon monoxide (DLco) is usually measured by the single breath method with a 10-second breath hold. With the introduction of rapid gas analyzers, an alternative method for measurement of DLco, the intrabreath method, has been developed. The intrabreath method does not depend upon length of time or other conditions during either breath holding or expiration. The aim of this study was to compare the single breath method and intrabreath method of DLco measurement. DLco measured by the intrabreath method (DLco IB) was compared with DLco measured by the single breath method (DLco SB) in 32 normal subjects, 88 patients with obstructive impairment and 39 patients with restrictive impairment. DLco SB could not be measured in 2 patients with obstructive impairment and 7 patients with restrictive impairment, while in all except one patient with severe restrictive impairment, DLco IB was able to be measured. There was an excellent correlation between DLco IB and DLco SB in normal subjects (rho = 0.942, p < 0.0001). There was no difference in the mean value between DLco IB (21.0 +/- 5.4 ml/min/mmHg) and DLco SB (20.9 +/- 4.9 ml/min/mmHg). In the obstructive impairment group there was also an excellent correlation between DLco IB and DLco SB (rho = 0.922, p < 0.0001). In the mild or moderate obstructive impairment group (%FEV1 > 50%), no difference between DLco IB (11.8 +/- 5.80 ml/min/mmHg) and DLco SB (12.4 +/- 4.68 ml/min/mmHg) was found. In the severe obstructive impairment group (%FEV1 < 50%), the DLco IB (7.29 +/- 3.61 ml/min/mmHg) was lower than the DLco SB (8.58 +/- 3.24 ml/min/mmHg) (p < 0.0001). The relation between DLco SB and DLco IB was equally strong in patients with restrictive impairment (rho = 0.742, p < 0.0001). There was an excellent correlation between DLco IB and DLco SB in normal subjects, the obstructive impairment group and the restrictive impairment group. The intrabreath method therefore seems to be a useful and reliable alternative to the single breath method for clinical measurement of DLco.     

Mental retardation in a boy with congenital adrenal hypoplasia: a clue to contiguous gene syndrome involving DAX1 and IL1RAPL

We report on a 2 years and 9 months old Japanese boy with adrenal hypoplasia and mental retardation (MR) (developmental quotient approximately 60) which occurred in the absence of severe adrenal crisis and resultant brain damage. Cytogenetic and molecular studies were performed in this boy and his parents with normal phenotype, showing that the boy had a maternally derived approximately 2 Mb interstitial Xp deletion involving DAX1 (DSS-AHC critical region on the X chromosome, gene 1) for adrenal hypoplasia congenita and disrupting IL1RAPL (interleukin-1 receptor accessory protein-like) for non-specific MR. The results explain the development of MR in this boy in terms of contiguous gene syndrome, and suggest the importance of IL1RAPL analysis in patients with adrenal hypoplasia and MR.     

Development and evaluation of FSSG: frequency scale for the symptoms of GERD

Background The aim of this study was to produce a simplified questionnaire for evaluation of the symptoms of gastroesophageal reflux disease (GERD).Methods A total of 124 patients with an endoscopic diagnosis of GERD completed a 50-part questionnaire, requiring only yes or no answers, that covered various symptoms related to the upper gastrointestinal tract, as well as psychosomatic symptoms. The 12 questions to which patients most often answered yes were selected, and were assigned scores (never = 0; occasionally = 1; sometimes = 2; often = 3; and always = 4) to produce a frequency scale for symptoms of GERD (FSSG). Sensitivity, specificity, and accuracy of the FSSG questionnaire were evaluated in another group of patients with GERD and non-GERD. The usefulness of this questionnaire was evaluated in 26 other GERD patients who were treated with proton pump inhibitors for 8 weeks.Results When the cutoff score was set at 8 points, the FSSG showed a sensitivity of 62%, a specificity of 59%, and an accuracy of 60%, whereas a cutoff score of 10 points altered these values to 55%, 69%, and 63%. The score obtained using the questionnaire correlated well with the extent of endoscopic improvement in patients with mild or severe GERD.Conclusions This new questionnaire is useful for the objective evaluation of symptoms in GERD patients.     

Advanced Imaging for Barrett’s Esophagus and Early Neoplasia: Surface and Subsurface Imaging for Diagnosis and Management

Purpose of Review

Esophageal adenocarcinoma bears one of the fastest rising incidence of any cancers and generally arises in the setting of gastroesophageal reflux and Barrett’s esophagus. However, early detection of neoplasia can be challenging since most patients are asymptomatic until they progress to more advanced and less curable stages, and early dysplastic lesions can be small, multifocal, and difficult to detect. Clearly, new imaging tools are needed in light of sampling error associated with random biopsies, the current standard of practice.

Recent Findings

Advances in endoscopic imaging including virtual chromoendoscopy, confocal laser endomicroscopy, and subsurface imaging with optical coherence tomography have ushered in a new era for detecting subtle neoplastic lesions. Moreover, in light of esophagus-sparing treatments for neoplastic lesions, such tools are likely to guide ablation and follow-up management.

Summary

While there is no ideal single imaging modality to facilitate improved detection, staging, ablation, and follow-up of patients with dysplastic Barrett’s esophagus, new advances in available technology, the potential for multimodal imaging, and the use of computer-aided diagnosis and biomarkers all hold great promise for improving detection and treatment.

     

Identification of quantitative trait loci for serum cholesterol levels in stroke-prone spontaneously hypertensive rats

The stroke-prone spontaneously hypertensive rat (SHRSP) has been reported to show significantly lower levels of serum total cholesterol than the normotensive control strain Wistar-Kyoto rat (WKY). Because selective inbreeding was conducted for stroke proneness, this concomitantly inherited characteristic of SHRSP may play some pathophysiological role in stroke. We evaluated the genetic determinants of the cholesterol trait by estimating heritability and subsequently by undertaking a genome-wide screen with 161 genetic markers in F(2) progeny involving SHRSP and WKY (104 male and 106 female rats). Three quantitative trait loci (QTLs) were detected on rat chromosomes 5, 7, and 15. Markers from the linked region on chromosome 15 indicated significant evidence of linkage with a maximal log of the odds (LOD) score of 7.7, whereas those on chromosomes 5 and 7 cosegregated with the trait in a sex-specific manner (the QTL close to genetic marker D5 Mit5 reached an LOD score of 7.3 in males, and that close to D7 Mit10 reached an LOD score of 3.2 in females). The male-specific QTL on chromosome 5 appeared to overlap with previously reported QTLs for stroke-associated phenotypes, but an identical gene (or genes) appeared unlikely to control these and the cholesterol traits simultaneously. In the present study, serum cholesterol levels were shown to be highly genetically determined in SHRSP (the heritability estimates are 76% in males and 83% in females), and 3 QTLs with substantial effects were identified. Further work, however, is required to clarify whether the cholesterol trait is related to the etiology of stroke or has been retained by chance through the inbreeding process in SHRSP.