Is It Worthwhile to Perform Capsule Endoscopy for Asymptomatic Patients with Positive Immunochemical Faecal Occult Blood Test?

Background

The immunochemical faecal occult blood test (IFOBT) is widely performed for colorectal cancer screening, but the usefulness of IFOBT in the detection of disorders of the small intestine is unknown. The objective of this study was to investigate what proportion of IFOBT-positive subjects with negative colonoscopy and oesophagogastroduodenoscopy has pathologies of the small intestine detected by capsule endoscopy (CE).

Methods

Between October 2008 and June 2010, asymptomatic IFOBT-positive patients with negative total colonoscopy and oesophagogastroduodenoscopy underwent CE. CE findings were classified into three categories: P0 (no abnormalities, or findings without potential for bleeding), P1 (findings with uncertain potential for bleeding), P2 and (findings with high potential for bleeding).

Results

Fifty-three patients (37 males, 16 females; 52.1 ± 13.0 years) were included. There were no cases with P2, 19 cases with P1, and 34 cases with P0 (there were no abnormalities in 25 of 34 cases). As a result, lesions in the small intestine were detected in 28 cases. Additional examination was considered necessary for five patients after CE, but no abnormality was detected, and therapeutic intervention was not undertaken in any case. Caecal completion rate was 92.5%.

Conclusions

No significant pathologies of the small intestine were detected in asymptomatic IFOBT-positive cases with negative colonoscopy and oesophagogastroduodenoscopy. CE is of limited use in asymptomatic patients with positive IFOBT.     

Fluorometric determination of nitrite with 2,3-diaminonaphthalene by reverse phase HPLC under alkaline conditions

IntroductionIn this study, a simple and sensitive fluorometric HPLC method was described for the determination of nitrite, an indicator of nitric oxide production in biological samples.MethodsNitrite was reacted with 2,3-diaminonaphthalene (DAN) to form fluorescent 2,3-naphthotriazole (NAT). Because NAT has higher fluorescence intensity at alkaline conditions, a reverse phase HPLC method employing a polymer-based column was applied to separate NAT using an alkaline mobile phase system.ResultsNAT was well separated from DAN and other fluorescent substances with increased detection sensitivity under alkaline conditions. A linear relationship (r = 0.999) between the fluorescence intensity of NAT and the concentration of nitrite was observed in the range from 0 to 800 nM with the detection limit of about 25 nM.DiscussionThe present HPLC method appears suitable for routine analysis of nitrite in crude biological samples, since the polymer-based column can withstand rigorous cleaning with either acid or base.     

Comparative Study of Calcium Ion Dynamics and Contractile Response in Rat Middle Cerebral and Basilar Arteries

The objective of this study was to compare intracellular calcium concentration ([Ca²⁺]_i) and contractile responses in isolated rat middle cerebral artery (MCA) with those in basilar artery (BA) employing real-time confocal laser microscopy. KCl elicited transient [Ca²⁺]_i elevation and sustained contraction in both arteries; moreover, nearly equal responses were evident in both arteries. Application of 5-hydroxytryptamine (5-HT), vasopressin (VP), and α,β-methylene adenosine 5’-triphosphate (α,β-me ATP) also induced elevation of [Ca²⁺]_i and contraction in both arteries. The maximum response of 5-HT and VP necessary to increase [Ca²⁺]_i and to constrict the MCA was less in comparison to the BA; however, a linear relationship emerged between the maximum response of [Ca²⁺]_i and that of contraction. Additionally, the slope of the correlation regression line of MCA was nearly identical to that of BA. On the other hand, cyclopiazonic acid (CPA)-induced Ca²⁺ release from store sites following contraction of MCA was distinct from that of BA. In MCA, velocity of [Ca²⁺]_i elevation in smooth muscle cells and Ca²⁺-wave propagation along smooth muscle cells induced by 5-HT were slower than those in BA. These observations revealed that different regions of arteries along the same cerebral tissue may display distinct [Ca²⁺]_i response; moreover, this difference may be one reason for the distinct contractile response.     

Population Structure Dynamics of Mycobacterium tuberculosis Beijing Strains during Past Decades in Japan

We used 909 strains to compare the population structures of the Mycobacterium tuberculosis Beijing family between different birth-year cohorts in Japan. The results revealed that the spread of a modern sublineage that has high transmissibility is currently increasing, while the spread of an ancient sublineage, STK, has significantly decreased in younger generations.Comparative studies of the Mycobacterium tuberculosis population structure have generated interest in understanding its epidemiological relevance to human disease (2, 3, 9, 15, 21). One of the most extensively studied clades with respect to host-pathogen compatibility is the Beijing family (5, 7, 8, 16, 23), which is highly prevalent in East Asia (26). Recent studies have demonstrated the worldwide dissemination of the modern Beijing family strains (having IS6110 insertions in the NTF region) (1, 14, 17, 18) and have led to speculation about the hypervirulent features of this sublineage (4, 7, 13, 16). In contrast to the worldwide prevalence of modern Beijing strains, the ancient Beijing strains (having an intact NTF region) are highly diverse and dominant in Japan (11, 27). Studying this singularity of the Beijing strains in Japan would expand our understanding of the heterogeneity in the fitness of different sublineages. In this study, we used data from a population-based study lasting 5 years and 8 months to investigate the probable shift in the M. tuberculosis population structure during the previous decades and determine the future trend in Japan, with special attention to the modern Beijing strains.We obtained 909 M. tuberculosis isolates from newly diagnosed pulmonary tuberculosis (TB) patients between April 2002 and December 2007. These isolates accounted for approximately 70% of the new culture-positive pulmonary TB cases detected during the collection period in Kobe City. The isolates were phylogenetically classified as belonging to the Beijing clade or other clades by spoligotyping (12) and to the ancient and modern Beijing sublineages on the basis of the presence of IS6110 in the NTF region (19, 27). The ancient and modern Beijing strains were subclassified by analyzing 10 synonymous single-nucleotide polymorphisms (6, 8, 11). Molecular typing based on the variable number of tandem repeats (VNTR) method with 19 loci, which comprised the 15 loci of Supply et al. (24) and 4 hypervariable loci (QUB-11a, QUB-3232, VNTR-3820, and VNTR-4120) (10), was performed for all strains. Recent transmission was suggested by the clustering of identical VNTR profiles. The presence or absence of region of difference 181 (25) in all the Beijing strains was analyzed.Of the 909 isolates, 714 (78.5%) were classified as Beijing family strains (Table ​(Table1),1), and these included 44 Beijing-like strains. Except for the sequence type 11 (ST11) and ST26 sublineages, all the Beijing strains contained deletions in region of difference 181. All the modern strains harbored only one IS6110 insertion element. The non-Beijing family strains comprised 32 spoligotypes. The details of the genetic data of all isolates are summarized in Table S1 in the supplemental material.

TABLE 1.

Genotypic characteristics of M. tuberculosis isolates from 909 tuberculosis patients

A delayed and innocuous presentation of odontoid peg fracture – Implications for osteopaths

A case of a delayed presentation of an elderly patient with cervical instability as a result of an odontoid peg fracture sustained in childhood is presented. Implications for osteopaths are discussed.