Regional differences in hypertensive cardiovascular remodeling between fishing and farming communities in Japan

BACKGROUND

Effects of dietary n-3 polyunsaturated fatty acids (n-3 PUFA) intake on the cardiovascular system have been reported, and thus we hypothesized that the prevalence of hypertensive cardiovascular remodeling would be lower in a fishing than a farming community.

METHODS

We recruited 263 essential hypertensives from a fishing and 333 from a farming village; all subjects were ≥40 years (mean 73 years; 42% men). They were cross-sectionally examined for serum eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), asymmetric dimethylarginine (ADMA) levels, left ventricular mass index (LVMI), and common-carotid artery (CCA) and internal-carotid artery (ICA) intima-media thickness (IMT).

RESULTS

Compared to the patients in the farming village, those in the fishing village had higher serum EPA and DHA levels (63.3 vs.70.9 µg/ml, 137.2 vs.157.8 µg/ml) and lower ADMA levels (0.49 vs.0.47 nmol/ml; all P < 0.05). LVMI and both CCA-IMT and ICA-IMT levels were lower in the fishing than the farming village (113.2 vs.121.6 g/m(2), 0.88 vs.0.94 mm, 1.10 vs.1.17 mm: all P < 0.01) even after adjustment for age, sex, body mass index (BMI), duration of hypertensive medication, number of antihypertensive medications, and 24-h systolic blood pressure (SBP) level. The differences in LVMI and IMT levels between these communities also remained unchanged (all P < 0.01) after additional adjustment for the regional differences in EPA, DHA, and ADMA levels. A multivariable linear regression analysis showed that the difference in place of residence was independently associated with LVMI as well as with both CCA-IMT and ICA-IMT levels (all P < 0.01).

CONCLUSION

The prevalence of cardiovascular remodeling was significantly lower in patients in the fishing community than in those in the farming community. Further investigations are required to explain the mechanisms underlying this association.

Association of poor physical function and cognitive dysfunction with high nocturnal blood pressure level in treated elderly hypertensive patients

BACKGROUND

Our aim was to assess the association between poor physical function, cognitive dysfunction, and high nocturnal systolic blood pressure (SBP), all of which are markers of vulnerability or frailty in elderly persons.

METHODS

In this cross-sectional study of 148 treated ambulatory elderly hypertensives (mean age: 75.5 years; 30% men), we evaluated 24-h BP levels, physical function (walking speed and timed up-and-go (TUG) tests), and mini-mental state examination (MMSE). Poor physical function or cognitive dysfunction was defined as a walking speed ≤1.5 m/s or MMSE score <27 points (below the geometric means for either examination).

RESULTS

Both slower walking speed and lower MMSE scores were associated with high nocturnal SBP level, but not with daytime SBP level, even after adjustment for significant covariates (P = 0.05 and P < 0.01, respectively). Slower walking speed was significantly associated with the diminished nocturnal SBP dipping independent of the 24-h BP levels (P = 0.02). Compared with the patients who performed well on both physical and cognitive tests, or with those who had either poor physical function or cognitive dysfunction but not both, patients with both poor physical function and cognitive dysfunction had significantly higher nocturnal SBP levels (120 vs. 123 vs. 128 vs. 134 mm Hg; P = 0.008 for linear trend) and less marked nocturnal SBP dipping (-14.4 vs. -12.9 vs. -10.7 vs. -7.5%; P = 0.02 for linear trend) even after adjustment for significant covariates.

CONCLUSION

Poor physical function and/or cognitive dysfunction could be valid markers likely to be associated with high nocturnal SBP, information which could help yield more refined prognosis for treated elderly hypertensives.

Maritalea porphyrae sp. nov., isolated from a red alga (Porphyra yezoensis), and transfer of Zhangella mobilis to Maritalea mobilis comb. nov

Three Gram-negative, motile, aerobic bacteria were isolated from cultures of the marine red alga Porphyra yezoensis. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the novel strains were closely related to Maritalea myrionectae CL-SK30(T) (97.9% 16S rRNA gene sequence similarity) and Zhangella mobilis E6(T) (96.2 %). 16S rRNA gene sequence similarity between Z. mobilis E6(T) and M. myrionectae CL-SK30(T) was 97.9%. The DNA G+C contents of the isolates (49.4-50.0 mol%) were similar to those of M. myrionectae DSM 19524(T) (52.3 mol%) and Z. mobilis JCM 15144(T) (50.3 mol%). From these results, it was difficult to differentiate the genus Zhangella from the genus Maritalea. DNA-DNA hybridization demonstrated that the isolates belonged to a single species. The isolates could also be distinguished from M. myrionectae and Z. mobilis on the basis of chemotaxonomic and phenotypic features, including fatty acid composition (particularly C(16:1)ω7c), growth with 6-9% (w/v) NaCl, carbon utilization, oxidation patterns and so on. A novel species of the genus Maritalea is proposed to accommodate the three isolates, with the name Maritalea porphyrae sp. nov. The type strain is LCM-3(T) (=LMG 25872(T)=NBRC 107169(T)). Furthermore, it is proposed that Zhangella mobilis should be transferred from the genus Zhangella to the genus Maritalea, with the name Maritalea mobilis comb. nov. (type strain E6(T)=CGMCC 1.7002(T)=JCM 15144(T)).

Diversity and characterization of oxytetracycline-resistant bacteria associated with non-native species, white-leg shrimp (Litopenaeus vannamei), and native species, black tiger shrimp (Penaeus monodon), intensively cultured in Thailand

AIMS

This study aimed at surveying prevalence of oxytetracycline (OTC)-resistant bacteria in the white-leg shrimp Litopenaeus vannamei, and the black tiger shrimp Penaeus monodon, intensively cultured in Thailand. We investigated the phylogenetic diversity of the bacterial isolates, as well as the minimum inhibitory concentration (MIC) of OTC, the occurrence of major OTC-resistant genes and multiple-antibiotic resistance in the isolates.

METHODS AND RESULTS

Shrimps were collected from culture ponds, and the homogenates of whole bodies were plated on tryptic soy agar supplemented with or without OTC. Percentages of OTC-resistant bacteria were 0·3-52·1% in white-leg samples and 0·008-22·3% in black tiger samples. Analyses of 16S rDNA sequences indicated that most OTC-resistant isolates were closely related to Aeromonas spp. and Lactococcus garvieae. MICs of OTC were 4-128 μg ml(-1) in the OTC-resistant aeromonads and 128-256 μg ml(-1) in OTC-resistant L. garvieae. OTC resistance was found to be conferred by the genes tet(A), tet(C), tet(D), tet(E), tet(M) and tet(S), detected either singly or in pairs. No resistance to ceftazidime, imipenem or chloramphenicol was observed in any isolate.

CONCLUSIONS

Both species of shrimp are associated with OTC-resistant bacteria, occasionally at high densities exceeding 10(6) cfu g(-1). The associated bacteria, predominantly Lactococcus and Aeromonas genera, are potential pathogens and are reservoirs of a variety of OTC-resistant genes.

SIGNIFICANCE AND IMPACT OF THE STUDY

Cultured shrimps can be vehicle to carry OTC-resistant bacteria to domestic and foreign consumers via the food chain. Very low populations of OTC-resistant bacteria observed in the several ponds suggest that levels of the resistant bacteria are artificially high and should be reduced in farmed shrimps.

High incidence of tumors in diabetic thrombin activatable fibrinolysis inhibitor and apolipoprotein E double-deficient mice

BACKGROUND

Activation of the complement system has been implicated in tumor growth. The antifibrinolytic protein, activated thrombin-activatable fibrinolysis inhibitor (TAFIa), can modulate the activation of the complement system by inactivating the anaphylatoxins C3a and C5a. The apolipoprotein-E (ApoE) genotype has been associated with carcinogenesis.

OBJECTIVE

The aim of this study was to evaluate whether TAFIa can affect the development of cancer in the ApoE-deficient mouse model.

METHODS

TAFI and ApoE double-knockout mice were generated. A group of mice was treated with the diabetogenic and carcinogenic compound streptozotocin (stz). Mice treated with saline, single knockout mice and wild-type (wt) mice served as controls.

RESULTS

Six months after treatment with stz, mice were sacrificed. Hepatic tumors were found in male double-knockout mice treated with stz but none was found in control animals that were not treated with stz or in single knockout of ApoE or wt animals. There was no significant difference in coagulation system activation between the groups of mice. The plasma concentrations of C5a, factor D and transforming growth factor-β1 were increased in TAFI/ApoE double-deficient mice treated with stz compared with the mice of the same genotype treated with saline.

CONCLUSION

Apo-E deficiency alone was not associated with tumors but the lack of TAFI appears to make the mice permissive for tumor formation in ApoE mice.

Up-regulation of connexin 32 gene by 5-aza-2'-deoxycytidine enhances vinblastine-induced cytotoxicity in human renal carcinoma cells via the activation of JNK signalling

Enforced expression of connexin (Cx) 32 gene, a member of gap junction gene family and a tumor suppressor gene in human renal cell carcinoma (RCC), enhanced vinblastine (VBL)-induced cytotoxicity on RCC cells, due to the suppression of multidrug resistance 1 (MDR1) gene product, P-glycoprotein (P-gp). Also, Cx32 gene in RCC is silenced by hypermethylation of CpG islands in a promoter region of the Cx gene. In this study, we investigated if a DNA demethylating agent, 5-aza-2'-deoxycytidine (5-Aza) could enhance susceptibility of RCC cells (Caki-1) to VBL. We found that 5-Aza treatment up-regulated Cx32 in Caki-1 cells, and the induction of the Cx led to the suppression of P-gp through inhibition of Src and subsequent activation of c-Jun NH(2)-terminal kinase (JNK). Moreover, increased transcription activity of c-Jun by the JNK activation contributed to the down-regulation of MDR1, thus indicating a central role of JNK signalling to suppress P-gp level in 5-Aza-treated Caki-1 cells. Chemical sensitivity to VBL in Caki-1 cells was increased by 5-Aza pre-treatment, and this effect was abrogated by short interfering RNA (siRNA)-mediated knockdown of Cx32. Furthermore, co-treatment of 5-Aza or a P-gp inhibitor with VBL drastically enhanced JNK activation comparing to only VBL treatment in Caki-1 cells. These results suggest that the restoration of Cx32 by 5-Aza pre-treatment improves chemical tolerance on VBL in Caki-1 cells and that the JNK activation is a key factor to induce the effect.

Comparison of pressure resistances of spores of six bacillus strains with their heat resistances

The pressure resistances of the spores of six Bacillus strains were examined at 5 to 10(deg)C and were compared with their heat resistances. The pressure treatments (at 981 MPa for 40 min and at 588 MPa for 120 min) did not inactivate the spores of B. stearothermophilus IAM12043, B. subtilis IAM12118, and B. licheniformis IAM13417. However, these spores had large differences in heat resistance. The spores of B. megaterium IAM1166 were 9.3 times more pressure resistant but 246 times less heat resistant than those of B. stearothermophilus IAM11001. The spores of B. coagulans IAM1194 were activated by the pressure treatments. There was no correlation between these pressure and heat resistances.

Distribution of polyunsaturated Fatty acids in bacteria present in intestines of deep-sea fish and shallow-sea poikilothermic animals

The lipid and fatty acid compositions in nine obligate and facultative barophilic bacteria isolated from the intestinal contents of seven deep-sea fish were determined. Phospholipid compositions were simple, with phosphatidylethanolamine and phosphatidylglycerol predominating in all strains. Docosahexaenoic acid (DHA; 22:6n-3), which has not been reported in procaryotes except for deep-sea bacteria, was found to be present in eight strains at a level of 8.1 to 21.5% of total fatty acids. In the other strain, eicosapentaenoic acid (EPA; 20:5n-3) was present at a level of 31.5% of total fatty acids. Other fatty acids observed in all strains were typical of marine gram-negative bacteria. Subcultures from pouches prepared from intestinal contents of five deep-sea fish by the most-probable-number (MPN) method were analyzed for fatty acids, and all subcultures contained DHA and/or EPA. Accordingly, viable cell counts of bacteria containing DHA and EPA were estimated at a maximum of 1.3 x 10(sup8) and 2.4 x 10(sup8) cells per ml, respectively, and accounted for 14 and 30%, respectively, of the total cell counts in the intestinal contents of the deep-sea fish. In the case of 10 shallow-sea poikilothermic animals having bacterial populations of 1.1 x 10(sup6) to 1.9 x 10(sup9) CFU per ml in intestinal contents, no DHA was found in the 112 isolates examined, while production of EPA was found in 40 isolates from cold- and temperate-sea samples. These results suggest that DHA and EPA are involved in some adaptations of bacteria to low temperature and high pressure.

Magnetospheric vortex formation: self-organized confinement of charged particles

A magnetospheric configuration gives rise to various peculiar plasma phenomena that pose conundrums to astrophysical studies; at the same time, innovative technologies may draw on the rich physics of magnetospheric plasmas. We have created a "laboratory magnetosphere" with a levitating superconducting ring magnet. Here we show that charged particles (electrons) self-organize a stable vortex, in which particles diffuse inward to steepen the density gradient. The rotating electron cloud is sustained for more than 300 s. Because of its simple geometry and self-organization, this system will have wide applications in confining single- and multispecies charged particles.

Pulmonary hypertension is ameliorated in mice deficient in thrombin-activatable fibrinolysis inhibitor

BACKGROUND

The fibrinolytic system has been implicated in the pathogenesis of pulmonary hypertension (PH). Thrombin-activatable fibrinolysis inhibitor (TAFI) inhibits fibrinolysis and therefore its absence would be expected to increase fibrinolysis and ameliorate PH.

OBJECTIVE

The objective of the present study was to evaluate the effect of TAFI deficiency on pulmonary hypertension in the mouse.

METHODS AND RESULTS

PH was induced in C57/Bl6 wild-type (WT) or TAFI-deficient (KO) mice by weekly subcutaneous treatment with 600 mg kg(-1) monocrotaline (MCT) for 8 weeks. PH was inferred from right heart hypertrophy measured using the ratio of right ventricle-to-left ventricle-plus-septum weight [RV/(LV+S)]. Pulmonary vascular remodeling was analyzed by morphometry. TAFI-deficient MCT-treated and wild-type MCT-treated mice suffered similar weight loss. TAFI-deficient MCT-treated mice had reduced levels of total protein and tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), transforming growth factor-beta (TGF-beta) and monocyte chemoattractant protein-1 (MCP-1) in bronchial alveolar lavage compared with wild-type MCT-treated mice. The ratio of RV to (LV+S) weight was significantly higher in WT/MCT than in KO/MCT mice. The pulmonary artery wall area and vascular stenosis were both greater in MCT-treated WT mice compared with MCT-treated TAFI-deficient mice.

CONCLUSIONS

TAFI-deficient MCT-treated mice had less pulmonary hypertension, vascular remodeling and reduced levels of cytokines compared with MCT-treated WT animals, possibly as a result of reduced coagulation activation.

First results from the new RIKEN superconducting electron cyclotron resonance ion source (invited)

The next generation heavy ion accelerator facility, such as the RIKEN radio isotope (RI) beam factory, requires an intense beam of high charged heavy ions. In the past decade, performance of the electron cyclotron resonance (ECR) ion sources has been dramatically improved with increasing the magnetic field and rf frequency to enhance the density and confinement time of plasma. Furthermore, the effects of the key parameters (magnetic field configuration, gas pressure, etc.) on the ECR plasma have been revealed. Such basic studies give us how to optimize the ion source structure. Based on these studies and modern superconducting (SC) technology, we successfully constructed the new 28 GHz SC-ECRIS, which has a flexible magnetic field configuration to enlarge the ECR zone and to optimize the field gradient at ECR point. Using it, we investigated the effect of ECR zone size, magnetic field configuration, and biased disk on the beam intensity of the highly charged heavy ions with 18 GHz microwaves. In this article, we present the structure of the ion source and first experimental results with 18 GHz microwave in detail.

Coordination of {Mo142} Ring to La3+ Provides Elliptical {Mo134La10} Ring with a Variety of Coordination Modes

A 28-electron reduced C_2h-Mo-blue 34Ǻ outer ring diameter circular ring, [Mo₁₄₂O₄₂₉H₁₀(H₂O)₄₉(CH₃CO₂)₅(C₂H₅CO₂)]^30- (≡{Mo₁₄₂(CH₃CO₂)₅(C₂H₅CO₂)}) comprising eight carboxylate-coordinated (with disorder) {Mo₂} linkers and six defect pockets in two inner rings (four and three for each, respectively), reacts with La³⁺ in aqueous solutions at pH 3.5 to yield a 28-electron reduced elliptical C_i-Mo-blue ring of formula [Mo₁₃₄O₄₁₆H₂₀(H₂O)₄₆{La(H₂O)₅}₄{La(H₂O)₇}₄{LaCl₂(H₂O)₅}₂]^10- (≡{Mo₁₃₄La₁₀}), isolated as the Na₁₀[Mo₁₃₄O₄₁₆H₂₀(H₂O)₄₆{La(H₂O)₅}₄{La(H₂O)₇}₄{LaCl₂(H₂O)₅}₂]·144 H₂O Na⁺ salt. The elliptical structure of {Mo₁₃₄La₁₀} showing 36 and 31 Å long and short axes for the outer ring diameters is attributed to four (A-D) modes of LaO₉/LaO₇Cl₂ tricapped-trigonal-prismatic coordination (TTP) geometries. Two different LaO₂(H₂O)₇ and one LaO₂(H₂O)₂Cl₂ TTP geometries (as A-C modes) for each of two inner rings result from the coordination of all three defect pockets of the inner ring for {Mo₁₄₂(CH₃CO₂)₅(C₂H₅CO₂)}, and two LaO₄(H₂O)₅ TTP geometries (as D mode) result from the displacement of two (acetate/propionate-coordinated) binuclear {Mo₂} linkers with La³⁺ in each inner ring. The isothermal titration calorimetry (ITC) of the ring modification from circle to ellipsoid, showing the endothermic reaction of [La³⁺]/[{Mo₁₄₂(CH₃CO₂)₅(C₂H₅CO₂)}] = 6/1 with ΔH = 22 kJ⋅mol^-1, ΔS = 172 J⋅K^-1⋅mol^-1, ΔG = −28 kJ⋅mol^-1, and K = 9.9 × 10⁴ M^-1 at 293 K, leads to the conclusion that the coordination of the defect pockets to La³⁺ precedes the replacement of the {Mo₂} linkers with La³⁺. ¹³⁹La- NMR spectrometry of the coordination of {Mo₁₄₂(CH₃CO₂)₅(C₂H₅CO₂)} ring to La³⁺ is also discussed.

Direct effects of protein S in ameliorating acute lung injury

OBJECTIVE

Protein S may exert an anticoagulant activity by enhancing the anticoagulant activity of activated protein C and/or by directly inhibiting the prothrombinase complex. Protein S itself may also directly regulate inflammatory responses and apoptosis. The role of protein S in acute lung injury (ALI) was unknown. This study evaluated the effect of protein S on ALI in the mouse.

METHODS

Animal ALI was induced in C57/BL6 mice by intratracheal instillation of lipopolysaccharide (LPS). Mice were treated with protein S or saline by intraperitoneal injection 1 h before LPS instillation.

RESULTS

Activated protein or protein S alone and combined activated protein C + protein S therapy decreased inflammatory markers and cytokines in mice with acute lung injury. In LPS-treated mice compared with controls ALI was induced as shown by significantly increased levels of total protein, tumor necrosis factor-alpha, interleukin-6 and monocyte chemoattractant protein-1 in the bronchoalveolar lavage fluid. Mice with ALI treated with protein S had significantly decreased concentrations of tumor necrosis factor-alpha and interleukin-6 in the lung compared with untreated animals. Thrombin-antithrombin III, a marker of the activity of the coagulation cascade, was unchanged. Protein S inhibited the expression of cytokines in vitro and increased activation of the Axl tyrosine kinase pathway in A549 epithelial cells.

CONCLUSION

Protein S protects against LPS-induced ALI, possibly by directly inhibiting the local expression of inflammatory cytokines without affecting coagulation.

Characterization of crustin antimicrobial proteins from Japanese spiny lobster Panulirus japonicus

Crustin antimicrobial proteins (PJC1-4) were identified from a phyllosoma library of Japanese spiny lobster, Panulirus japonicus. The deduced amino acid sequences of PJC1-4 contained open reading frames of 130, 139, 124 and 150 amino acid residues, respectively. These proteins contained a glycine-rich region at the N-terminus and 12 conserved cysteine residues containing a single whey acidic protein (WAP) domain at the C-terminus. A phylogenetic tree and sequences alignment analyses revealed that PJC1-4 are more closely related to shrimp crustins than to other lobster crustins. Transcripts of PJC1, 3 and 4 were detected in heart, nerves, intestine, hemocytes, gills and hepatopancreas, while transcripts of PJC2 were detected only in nerves.

A case of fulminant type 1 diabetes with coxsackie B4 virus infection diagnosed by elevated serum levels of neutralizing antibody

A 39-year-old woman with hyperglycemia and ketonuria but with normal HbA1c level was diagnosed as having fulminant type 1 diabetes. The patient had 8-fold increase in the plasma titer of coxsackie B4 virus neutralizing antibody. Infection with coxsackie B4 virus was associated with fulminant type 1 diabetes.

pfaB products determine the molecular species produced in bacterial polyunsaturated fatty acid biosynthesis

When pDHA4, a vector carrying all five pfaA-pfaE genes responsible for docosahexaenoic acid (DHA; 22:6) biosynthesis in Moritella marina MP-1, was coexpressed in Escherichia coli with the individual pfaA-pfaD genes for eicosapentaenoic acid (EPA; 20:5) biosynthesis from Shewanella pneumatophori SCRC-2738, both polyunsaturated fatty acids were synthesized only in the recombinant carrying pfaB for EPA synthesis. Escherichia coli coexpressing a deleted construct comprising pfaA, pfaC, pfaD and pfaE for EPA and pfaB for DHA produced EPA and DHA. Both EPA and DHA were detected in bacteria that inherently contained pfa genes for DHA. These results suggest that PfaB is the key enzyme determining the final product in EPA or DHA biosynthesis.

Presence of thrombin-activatable fibrinolysis inhibitor in Helicobacter pylori-associated gastroduodenal disease

Thrombin-activatable fibrinolysis inhibitor (TAFI) plays a role in the regulation of coagulation and inflammation. In addition to inhibiting the fibrinolytic system, TAFI may also regulate the bradykinin and complement systems. We hypothesized that TAFI also plays a role in defense mechanisms of the gastric mucosa during Helicobacter pylori infection. This study comprised 65 patients with gastroduodenal disorders: 41 patients with H. pylori infection, 13 without, and 11 patients with cured H. pylori infection. The gastric intramucosal concentrations of TAFI were measured by enzyme immunoassay. The gastric levels of TAFI and plasminogen activator inhibitor-1 were significantly increased in patients with H. pylori compared to those without infection or cured H. pylori. The presence of TAFI was detected in gastric mucosal epithelial cells. The concentration of TAFI was correlated with the degree of gastric mucosal atrophy, inflammation, and disease activity. These results show that TAFI is present in the gastric mucosa and that it may play a role in the pathogenesis of H. pylori infection-associated gastroduodenal disorders.

Characterization of two isoforms of Japanese spiny lobster Panulirus japonicus defensin cDNA

Antimicrobial peptides (AMPs) are components of the innate immune responses that form the first line of host defense against pathogens. In this study, cDNAs of two new isoforms of defensin (designated PJD1 and PJD2) from a Japanese spiny lobster Panulirus japonicus haemocytes cDNA library were cloned and sequenced. PJD1 and PJD2 consist of 656 and 673 nucleotides encoding putative proteins of 66 and 64 amino acids, respectively. The isoforms share 74.2% amino acid identity. In a phylogenetic analysis, the peptides clustered with vertebrate defensins and were closely mostly related to chicken beta-defensin. PJD1 and PJD2 were detected in all tissues examined including heart, nerves, intestine, haemocytes, gills and hepatopancreas.

First demonstration of electron scattering using a novel target developed for short-lived nuclei

We carried out a demonstrative electron scattering experiment using a novel ion-trap target exclusively developed for short-lived highly unstable nuclei. Using stable 133Cs ion as a target, this experiment completely mimicked electron scattering off short-lived nuclei. Achieving a luminosity higher than 10;{26} cm;{-2} s;{-1} with around only 10;{6} trapped ions on the electron beam, the angular distribution of elastic scattering was successfully measured. This experiment clearly demonstrates that electron scattering off rarely produced short-lived nuclei is practical with this target technique.

Risks and clinical features of colorectal cancer complicating Crohn's disease in Japanese patients

BACKGROUND AND AIM

No reports on the relative risk of development of colorectal cancer (CRC) in Japanese patients with Crohn's disease (CD) have been published. The present study aimed to investigate the relative risk and the clinical features of CRC complicating CD among patients managed at Fukuoka University Chikushi Hospital, Fukuoka, Japan (a tertiary referral center for inflammatory bowel diseases).

METHODS

The clinical backgrounds were analyzed of 512 patients with CD who have been treated by our department during the last 20-year period (1985-2005) (total 6212.6 person years at risk). The standardized incidence ratio (SIR) refers to the relative risk of CRC in the subjects as compared with that in a sex- and age-matched healthy population.

RESULTS

There were six cases with CRC. The SIR was significantly higher (3.2-fold higher; 95% confidence interval, 1.2-6.9 P < 0.05) in the CD group than in the healthy population. The significant risk factors identified were female sex, mixed small and large bowel type, observation period over 20 years, onset of CD at less than 25 years of age, presence of anal disease, and positive history of surgery. The prognosis for the six cases with CRC was very poor (five cases died within 1.5 years).

CONCLUSION

The risk of CRC in longstanding CD in Japan was similar to that in Western countries. The necessity of surveillance in the management of CD would also need to be discussed in the near future, especially in CD patients with anal lesions or fistulae, and are particularly important in patients with a 20-year or more history of CD.