Validation study for development of the Japan NBI Expert Team classification of colorectal lesions

BACKGROUND AND AIM

The Japan narrow-band imaging (NBI) Expert Team (JNET) was organized to unify four previous magnifying NBI classifications (the Sano, Hiroshima, Showa, and Jikei classifications). The JNET working group created criteria (referred to as the NBI scale) for evaluation of vessel pattern (VP) and surface pattern (SP). We conducted a multicenter validation study of the NBI scale to develop the JNET classification of colorectal lesions.

METHODS

Twenty-five expert JNET colonoscopists read 100 still NBI images with and without magnification on the web to evaluate the NBI findings and necessity of the each criterion for the final diagnosis.

RESULTS

Surface pattern in magnifying NBI images was necessary for diagnosis of polyps in more than 60% of cases, whereas VP was required in around 90%. Univariate/multivariate analysis of candidate findings in the NBI scale identified three for type 2B (variable caliber of vessels, irregular distribution of vessels, and irregular or obscure surface pattern), and three for type 3 (loose vessel area, interruption of thick vessel, and amorphous areas of surface pattern). Evaluation of the diagnostic performance for these three findings in combination showed that the sensitivity for types 2B and 3 was highest (44.9% and 54.7%, respectively), and that the specificity for type 3 was acceptable (97.4%) when any one of the three findings was evident. We found that the macroscopic type (polypoid or non-polypoid) had a minor influence on the key diagnostic performance for types 2B and 3.

CONCLUSION

Based on the present data, we reached a consensus for developing the JNET classification.

Narrow-band imaging (NBI) magnifying endoscopic classification of colorectal tumors proposed by the Japan NBI Expert Team

Many clinical studies on narrow-band imaging (NBI) magnifying endoscopy classifications advocated so far in Japan (Sano, Hiroshima, Showa, and Jikei classifications) have reported the usefulness of NBI magnifying endoscopy for qualitative and quantitative diagnosis of colorectal lesions. However, discussions at professional meetings have raised issues such as: (i) the presence of multiple terms for the same or similar findings; (ii) the necessity of including surface patterns in magnifying endoscopic classifications; and (iii) differences in the NBI findings in elevated and superficial lesions. To resolve these problems, the Japan NBI Expert Team (JNET) was constituted with the aim of establishing a universal NBI magnifying endoscopic classification for colorectal tumors (JNET classification) in 2011. Consensus was reached on this classification using the modified Delphi method, and this classification was proposed in June 2014. The JNET classification consists of four categories of vessel and surface pattern (i.e. Types 1, 2A, 2B, and 3). Types 1, 2A, 2B, and 3 are correlated with the histopathological findings of hyperplastic polyp/sessile serrated polyp (SSP), low-grade intramucosal neoplasia, high-grade intramucosal neoplasia/shallow submucosal invasive cancer, and deep submucosal invasive cancer, respectively.

The host galaxy of a fast radio burst

In recent years, millisecond-duration radio signals originating in distant galaxies appear to have been discovered in the so-called fast radio bursts. These signals are dispersed according to a precise physical law and this dispersion is a key observable quantity, which, in tandem with a redshift measurement, can be used for fundamental physical investigations. Every fast radio burst has a dispersion measurement, but none before now have had a redshift measurement, because of the difficulty in pinpointing their celestial coordinates. Here we report the discovery of a fast radio burst and the identification of a fading radio transient lasting ~6 days after the event, which we use to identify the host galaxy; we measure the galaxy's redshift to be z = 0.492 ± 0.008. The dispersion measure and redshift, in combination, provide a direct measurement of the cosmic density of ionized baryons in the intergalactic medium of ΩIGM = 4.9 ± 1.3 per cent, in agreement with the expectation from the Wilkinson Microwave Anisotropy Probe, and including all of the so-called 'missing baryons'. The ~6-day radio transient is largely consistent with the radio afterglow of a short γ-ray burst, and its existence and timescale do not support progenitor models such as giant pulses from pulsars, and supernovae. This contrasts with the interpretation of another recently discovered fast radio burst, suggesting that there are at least two classes of bursts.

P-ρ-T measurements of H2O up to 260 GPa under laser-driven shock loading

Pressure, density, and temperature data for H2O were obtained up to 260 GPa by using laser-driven shock compression technique. The shock compression technique combined with the diamond anvil cell was used to assess the equation of state models for the P-ρ-T conditions for both the principal Hugoniot and the off-Hugoniot states. The contrast between the models allowed for a clear assessment of the equation of state models. Our P-ρ-T data totally agree with those of the model based on quantum molecular dynamics calculations. These facts indicate that this model is adopted as the standard for modeling interior structures of Neptune, Uranus, and exoplanets in the liquid phase in the multi-Mbar range.

Optimal timing for resuming antithrombotic agents and risk factors for delayed bleeding after endoscopic resection of colorectal tumors

Aim. To examine optimal timing for resuming antithrombotic agents and risk factors for delayed bleeding after endoscopic resection of colorectal tumors. Method. Of 1,970 polyps larger than 10 mm removed by polypectomy, endoscopic mucosal resection, or endoscopic submucosal dissection, delayed bleeding, which was designated as bleeding that occurred 6 or more hours after endoscopic treatment, occurred in 52 cases (2.6%); 156 nonbleeding cases matched for age and gender were controls in this single-institution retrospective case-control study. We investigated (1) patient-factors: resuming antithrombotic agents within 5 days following endoscopic resection, hypertension, and diabetes mellitus; and (2) tumor-factors: morphology, size, location, and resection technique by conditional logistic regression. Results. By multivariate analysis resumption of anticoagulants within 5 days was a significant risk factor for delayed bleeding (OR 10.2; 95% CI = 2.7-38.3; P = 0.0006). But resuming a thienopyridine within 5 days was not (OR 0.9; 95% CI = 0.1-2.6; P = 0.40). Other patient- and tumor-factors were not significant. Conclusion. Resuming anticoagulants within 5 days after endoscopic treatment was associated with delayed bleeding whereas resuming thienopyridines was not.

Multiple primary malignant neoplasms of three early cancer lesions: a case report

Multiple primary malignant neoplasms (MPMNs) are rarely reported and it is important to give early diagnosis and proper therapy for these patients. Here reported a case of 62-year-old man with concomitant three early stage cancer lesions in upper gastrointestinal tract, all of which were detected by endoscopy. The first one was an IIc-type lesion at angular part of stomach under endoscopy, which was histologically confirmed to be a mucosal well-differentiated adenocarcinoma. The patient underwent a standard radical gastrectomy for the lesion after the failure of endoscopic treatment. The other two neoplasms were observed during follow-up and were indicated as early stage lesions by synthesizing information from endoscopy, endoscopic ultrasonography, computed tomography and biopsy. One displayed as a hyperemic patch (3 cm×4 cm in size) located at the part of esophagus 27 cm away from the incisor teeth and was proved to be moderately differentiated squamous cancer by histopathological examination. The other was an IIc-type lesion (3.0 cm×3.5 cm in size) located at the part of esophagus 36 cm away from the incisor teeth, and the biopsy result showed a poorly differentiated squamous carcinoma. Both the two lesions were treated with radical radiation because the patient refused surgery management. No recurrence of former lesions or occurrence of novel lesions were observed during post-treatment follow-up, suggesting radical radiation might be effective for this patient.

Evaluation of new subclassification of type V(I) pit pattern for determining the depth and type of invasion of colorectal neoplasm

BACKGROUND

Colorectal neoplasms with a type V(I) pit pattern include various lesions, such as adenomas, intramucosal cancers, and submucosal carcinomas.

METHODS

We analyzed 96 colorectal neoplasms with a type V(I) pit pattern and identified six different variants: (1) unclear outline of the pit; (2) irregular margins of the pit; (3) narrowing of the pit; (4) ragged array of the pit; (5) high residual density of the pit; (6) abnormal branching of the pit. We examined the relationship between the appearance of each V(I) pit pattern and histology, including the depth of invasion.

RESULTS

In univariate logistic regression analysis the unclear outline, irregular margins, and narrowing of the pit were significantly associated with a submucosal (SM) invasion ≥1000 μm (P < 0.01). In multivariate logistic regression analysis, unclear outline of the pit was shown to be the only significant predictor of highly invasive submucosal cancer (odds ratio = 24.20, P < 0.0001). Regarding tumor morphology, the following were significantly associated with an SM invasion ≥1000 μm: in protruded type, ragged array (P = 0.022), irregular margins of the pit (P = 0.011), and unclear outline of the pit (P < 0.01); in flat type, irregular margins of the pit (P < 0.01) and unclear outline of the pit (P < 0.01); and in the depressed type, narrowing of the pit (P = 0.015) and unclear outline of the pit (P < 0.01).

CONCLUSIONS

Subclassification of the type V(I) pit pattern is useful for determining the depth of invasion of colorectal neoplasms.

Relationship between endoscopic findings and clinical severity in ischemic colitis

BACKGROUND AND AIM

The incidence of ischemic colitis (IC) in Japan has been increasing due to the westernization of diet and the aging population. The aim of this study was to evaluate the relationship between endoscopic findings and clinical severity in IC.

METHODS

This retrospective analysis included 106 cases diagnosed with IC that were divided into two groups based on endoscopic findings in the acute stage: redness and erosion (RE) versus longitudinal and circumferential ulcers (LCU). The clinical variables were compared between the two groups. In addition, we investigated the risk factors of IC associated with the severity of the endoscopic findings by multivariate logistic regression analysis.

RESULTS

The percentage of cases presenting abdominal pain was significantly higher in the LCU group than that in the RE group (p=0.002), as were the baseline serum CRP levels (p=0.0001). The periods of hospitalization in LCU group were longer than in the RE group (p=0.0001). Multivariate logistic regression analysis indicated that ischemic heart disease (IHD) and connective tissue disease were the independent explanatory factor associated with the endoscopic severity of IC (p<0.05).

CONCLUSION

We showed clearly that the two endoscopic classifications were accurate indicators of severity and could be used to anticipate severity of IC. Furthermore, we confirmed that IHD and connective tissue disease were the exacerbating factor associated with the severity of endoscopic findings in IC.

Colonic mucosal lesions associated with long-term or short-term administration of nonsteroidal anti-inflammatory drugs

AIM

The effects of short- or long-term administration of nonsteroidal anti-inflammatory drugs (NSAIDs) on the colon have not been well characterized. We assessed the risk of developing colonic mucosal lesions according to the duration of exposure to NSAIDs: short-term and/or long-term use.

METHOD

A case-controlled study was performed by reviewing medical records for endoscopic findings, underlying disease, pre-endoscopic symptoms, category of NSAIDs used and duration of use. The patients underwent colonoscopy between January and October 2004, and 75 colitis cases and 1801 non-colitis controls were identified. The prevalence of NSAID use was compared between the cases and controls. The age- and sex- adjusted odds ratios (OR) were estimated using multiple logistic regression models.

RESULTS

NSAIDs had been used in colitis cases and non-colitis controls for over six months in 20.0% and 12.7%, and for one week in 4.0% and 2.1%. Overall 76.0% and 85.2% had not received NSAIDs. The adjusted OR (95% confidence interval) for colonic mucosal lesions with short- and long term NSAID administration combined vs. non-use was 2.04 (1.16-3.61). When determined separately for short- and long-term NSAID users, the adjusted ORs were 1.48 (0.42-5.25) and 2.21 (1.19-4.11), compared to non-users. These values signify a trend toward an increased frequency of colonic mucosal lesions with longer use of NSAIDs (P=0.011 for trend).

CONCLUSION

Long-term use of NSAIDs increased the risk of colonic mucosal lesions, suggesting that NSAIDs may contribute to the pathogenesis of colonic ulcer or colitis.

Spondylolysis originates in the ventral aspect of the pars interarticularis: a clinical and biomechanical study

Lumbar spondylolysis is a stress fracture of the pars interarticularis. We have evaluated the site of origin of the fracture clinically and biomechanically. Ten adolescents with incomplete stress fractures of the pars (four bilateral) were included in our study. There were seven boys and three girls aged between 11 and 17 years. The site of the fracture was confirmed by axial and sagittal reconstructed CT. The maximum principal tensile stresses and their locations in the L5 pars during lumbar movement were calculated using a three-dimensional finite-element model of the L3-S1 segment. In all ten patients the fracture line was seen only at the caudal-ventral aspect of the pars and did not spread completely to the craniodorsal aspect. According to the finite-element analysis, the higher stresses were found at the caudal-ventral aspect in all loading modes. In extension, the stress was twofold higher in the ventral than in the dorsal aspect. Our radiological and biomechanical results were in agreement with our clinical observations.

Clinicopathological characteristics of colorectal cancer less than 10 mm in diameter and invading submucosa and below

BACKGROUND AND AIMS

Identifying the invasive depth of cancers less than 10 mm in diameter remains a challenge. This study examines the clinicopathological characteristics of colorectal cancers less than 10 mm in diameter and invading submucosal layer (SM)3 and below, which require surgery and must never be treated by endoscopic mucosal resection.

METHODS

We studied 54 cases of colorectal cancer less than 10 mm in diameter and invading the submucosa and deeper tissues, by dividing them into two groups: those invading SM1 and SM2 versus those invading SM3 and below. We investigated the clinicopathological characteristics of cancers invading SM3 and below by comparing them with cancers invading SM1 and SM2. Similarly, 38 cases, whose endoscopic findings could be analyzed, were selected and examined.

RESULTS

In cases invading SM3 and below, the rates of moderately to poorly differentiated adenocarcinoma, lymphatic and venous permeation and lymph node metastasis were significantly higher than those invading SM1 and SM2. Among cases invading SM3 and below, the presence of endoscopic findings-including white spots of the protruded type, and fullness, white spots, hardness and protruded lesions in the depressed area of the depressed type-was significantly higher than among those invading SM1 and SM2.

CONCLUSION

Colorectal cancers less than 10 mm in diameter and invading SM3 and below have high malignant potential. Cancers of this invasive depth can be identified by looking for characteristics such as white spots, fullness, hardness and protruded lesions in the depressed area. Careful endoscopic observation for these signs aids in determining the appropriate treatment.

Ultrasound-guided percutaneous drainage may decrease the mortality of severe acute pancreatitis

OBJECTIVES

To evaluate the efficacy and safety of ultrasound-guided percutaneous catheter drainage (PCD) treatment for severe acute pancreatitis compared to conservative and conventional surgical treatments.

METHODS

Eighty-one patients with severe acute pancreatitis (SAP) were admitted and divided into three groups: forty-nine cases in the conservative therapy group; nineteen cases in the surgery group; and thirteen cases in the PCD therapy group. Forty-five patients with a CT severity index (CTSI) < or = 8.0 received conservative treatment. One patient with CTSI = 7.0 underwent surgery. Thirty-five patients with a CTSI > 8.0 were randomly selected for surgery or PCD treatment. After randomization, six patients (four patients in the surgery group and two patients in the PCD group) were dropped from the study. The total number of patients included in the surgery and PCD groups was sixteen and thirteen, respectively.

RESULTS

Four patients (8.2%) in the conservative therapy group died, five patients (31.3%) in surgery group with a CTSI > 8.0 died, and all patients in the PCD group survived. The mortality rate was lower in the PCD group than in the surgery group (P = 0.048). The serum C-reactive protein (CRP) level recovered more quickly in patients in the PCD group compared to those in the surgery group (P < 0.001).

CONCLUSIONS

Patients with SAP and a CTSI < or = 8.0 could be treated with conservative therapy, while patients with a CTSI > 8.0 should be treated with surgery or PCD therapy if the life-threatening complications of extensive fluid collection or necrosis are a factor. However, PCD therapy used in a timely manner for drainage may decrease mortality in patients with SAP, decrease inflammatory mediator release, and avoid incidence of severe sepsis or acute respiratory distress syndrome (ARDS) and emergency surgery.

Correlations among total colonoscopic findings, clinical symptoms, and laboratory markers in ulcerative colitis

BACKGROUND AND AIM

Colonoscopy plays an integral role in the diagnosis, management and surveillance of ulcerative colitis (UC). In the present study we assessed the relationship between endoscopic and histological findings, clinical symptoms, and laboratory data.

METHODS

We performed total colonoscopy examinations in 54 consecutive patients with UC. Seven segments (appendiceal region, cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum) were scored for endoscopic and histological activity. The patients were also evaluated using a symptom-activity index and laboratory markers: C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and white blood cell (WBC) and platelet (plt) counts.

RESULTS

There was a significant positive correlation between endoscopic and histological scores (r(s)=0.738), and between symptom activity score, endoscopic score (r(s)=0.444), and histological score (r(s)=0.557). Although the endoscopic and histological scores of distal colonic lesions (rectum-sigmoid, endoscopic: r(s)=0.515, histological: r(s)=0.624) correlated with clinical symptoms, there was no similar correlation for the proximal colon (appendiceal region-descending; endoscopic, r(s)=0.268, histological, r(s)=0.329). CRP, ESR, and WBC count also correlated with the sum of endoscopic and histological scores (CRP, r(s)=0.447, r(s)=0.369; ESR, r(s)=0.483, r(s)=0.589; WBC, r(s)=0.338, r(s)=0.330), whereas platelet count did not (r(s)=0.171, r(s)=0.210). In particular, CRP and ESR were well correlated with the activity of proximal colonic lesions (CRP, r(s) = 0.474, r(s)=0.480; ESR, r(s) = 0.423, r(s)=0.529) rather than with that of distal lesions (CRP, r(s)=0.236, r(s)=0.212; ESR, r(s)=0.368, r(s)=0.497).

CONCLUSIONS

In this study, clinical symptoms reflected the activity of distal colonic lesions, whereas CRP and ESR reflected the activity of proximal lesions. Therefore, total colonoscopy may be indicated when CRP or ESR is elevated in UC patients in clinical remission.

Malignant lymphoma in the ileum diagnosed by double-balloon enteroscopy

A 73-year old man presented with abdominal pain. A tumor with central ulceration was observed in the ileum using double-balloon enteroscopy. Histological findings of the biopsy specimens were consistent with malignant lymphoma. Double-balloon enteroscopy confirmed the diagnosis of a malignant lymphoma tumor which was surgically resected. The patient is still in complete remission now.

Increased esophageal sensitivity to acid and saline in patients with nonerosive gastro-esophageal reflux disease

GOALS

To investigate the features of nonerosive reflux disease (NERD).

BACKGROUND

NERD is not considered as a milder form of erosive gastro-esophageal reflux disease (eGERD). Although the prevalence of NERD was reported to be high in our country, there have been very few studies about NERD.

STUDY

We performed upper gastrointestinal endoscopy to confirm the diagnosis of GERD. The modified acid perfusion test and saline perfusion test were performed in 7 control subjects, 14 NERD, and 11 eGERD patients. The stimulus-response function to acid and saline was quantified by the duration of typical symptom perception (minutes), total sensory intensity rating (0 to 10), and the perfusion sensory score (SS), which was defined as the product of minutes and the sensory intensity rating.

RESULTS

The mean value of SS by saline was 0 in control subjects, 12.0 in NERD patients, and 1.5 in eGERD patients (P<0.01 control vs. NERD, P<0.01 NERD vs. eGERD). The mean SS with acid was 0.9 in control subjects, 52.5 in NERD patients, and 23.0 in eGERD patients (P<0.01 control vs. NERD, control vs. eGERD, P<0.05 NERD vs. eGERD). A statistically significant association was shown between the acid and saline perfusion SSs with a correlation coefficient value of r=0.57 in the NERD group (P<0.05).

CONCLUSIONS

Both eGERD and NERD, but especially NERD, exhibited esophageal hypersensitivity not only to acid but also saline perfusion, suggesting that hyperalgesia to acid and other factors (eg, psychologic and/or autonomic nerve disturbance) may play some roles in symptom generation in NERD.

Location of early colorectal cancers at fold-top may reduce the risk of lymph node metastasis

PURPOSE

This study was designed to look for significant correlations between location of early colorectal cancer, distance from muscularis mucosae to muscularis propria, and the frequency of lymph node metastasis.

METHODS

A total of 166 early colorectal cancers, including 67 surgically resected lesions, were evaluated. The cancers were divided into two groups: metastatic and nonmetastatic. Cancer lesions were further subtyped at the fold-top or fold-bottom. Macroscopic classifications and histology were performed. Absolute invasive depth and distance from muscularis mucosae to muscularis propria was measured. Multivariate analysis was used to assess relationships among the variables.

RESULTS

The percentage of polypoid cancer lesions at fold-bottom was higher than at fold-top (74.5 vs. 51.8 percent), whereas flat-type cancer lesions at fold-bottom occurred less often than at fold-top (8.2 vs. 30.4 percent). Logistic regression showed that deep absolute invasive depth, lymphatic and vessel invasion, and cancer location (at fold-bottom) were the significant risk factors for early colorectal cancers leading to lymph-node metastasis. The distance from muscularis mucosae to muscularis propria with lymph-node metastasis (1,396.7 +/- 728.4 microm) was shorter than without lymph-node metastasis (3,533.9 +/- 2,507.8 microm; P < 0.01). Multivariate analysis showed that distance from muscularis mucosae to muscularis propria was a statistically significant factor for early colorectal cancers leading to lymph node metastasis (P = 0.0054).

CONCLUSIONS

We conclude that early colorectal cancers at the fold-top or with a long distance from muscularis mucosae to muscularis propria have less tendency to metastasize to lymph nodes. Clinically, these results provide evidence of a new indicator of endoscopic mucosal resection for early colorectal cancers at the fold-top.

Clinicopathological features of nonpolypoid colorectal tumors as viewed from the patients' background

BACKGROUND

This study was performed to characterize the clinicopathological features of colorectal tumors with flat-, depressed-, or protruded-type morphology (hereafter referred to simply as flat, depressed, or protruded lesions).

METHODS

There are two major types of colorectal tumor: polypoid (protruded) and nonpolypoid (flat and depressed). A total of 130 lesions from 130 patients with colorectal submucosal invasive cancer were classified into three groups according to their macromorphology seen during endoscopy: flat (laterally spreading) and depressed nonpolypoid tumors and protruded polypoid tumors. The following factors in the patients' background were evaluated: indication for colonoscopy, age, and family history of colorectal cancer in first-degree relatives (i.e., parents, siblings, children). We also compared the following characteristics of the tumors: size, location, depth of submucosal invasion, vascular invasion, and frequency of synchronous and metachronous tumor lesions.

RESULTS

The incidence of abnormal findings on follow-up studies after polypectomy as an indication for colonoscopy was significantly higher among patients with flat lesions (4/24, 16.7%) and depressed lesions (3/22, 13.6%) than among those with protruded lesions (1/84, 1.2%) (P < 0.01, P < 0.01). Patients with flat lesions (65.8 +/- 7.6 years old) were significantly older than those with protruded lesions (P < 0.05). The patients with flat tumors had a significantly higher rate of a family history of colorectal cancer (6/24, 25.0%) than patients with protruded or depressed lesions (P < 0.01, P < 0.05). The protruded lesions were significantly larger than the depressed lesions (size 13.3 +/- 6.7 mm) (P < 0.05), and the flat lesions (24.1 +/- 10.1 mm) were significantly larger than either the protruded or depressed lesions (P < 0.01, P < 0.01). Seventy-five percent (18/24) of the flat lesions were located in the right colon, and this proportion was significantly higher than that among the protruded or depressed lesions (P < 0.01, P < 0.01). The mean +/- SD depth of submucosal invasion was 1218 +/- 1034 microm in the flat lesions, 2392 +/- 1869 microm in the depressed lesions, and 2761 +/- 1929 microm in the protruded lesions, representing a significant difference (P < 0.05, P < 0.0001). Of the 24 patients with flat lesions, 9 (37.5%) showed vascular invasion; this proportion was significantly lower than that among patients with the depressed or protruded lesions (P < 0.01, P < 0.01). Patients with depressed lesions tended to have higher incidence of synchronous and metachronous malignant polyps than those with protruded or flat lesions.

CONCLUSION

It is important to examine the morphology of colorectal tumors when diagnosing them and planning the treatment strategy, including follow-up, after resection of nonpolypoid tumors. It is useful to know the patient's family history so nonpolypoid tumors can be accurately diagnosed.

Adult onset tethered cord syndrome associated with intradural dermoid cyst. A case report

STUDY DESIGN

A case report and a review of literature.

OBJECTIVES

To describe a rare case of adult onset tethered cord syndrome associated with intradural dermoid cyst.

SETTING

General Orthopedics, Japan.

METHODS

A 50-year-old woman was referred to us because of right leg pain and pollakiuria. Neurological examinations and radiological assessments including myelography, computerized tomography scan and Magnetic resonance image were carried out. We diagnosed it as the adult onset tethered cord syndrome associated with an intradural cystic lesion.

RESULTS

The cystic lesion was totally removed following laminectomy from L5 through S4. Histologically, the tumor was diagnosed as a dermoid cyst.

CONCLUSIONS

Intradural dermoid could produce adult onset tethered cord syndrome, but it was not reported in the English literatures to our knowledge.

Allelic loss analysis of early-stage flat-type colorectal tumors

BACKGROUND

Flat-type colorectal tumors are rare, but are known for their unusual flat morphology and aggressive clinical behavior despite their small size. To identify distinct genetic alterations, loss of heterozygosity (LOH) analysis was performed on microdissected tissues.

MATERIALS AND METHODS

DNA was extracted from multiple microdissected foci in 43 cases of early-stage flat-type colorectal tumors and LOH analysis was performed on 2q, 4q, 5q, 12q, 14q, 15q, 17p, 18q, 18p and 22q.

RESULTS

LOH patterns were detected in one of two forms: (i) homogeneous LOH throughout the microdissected foci, which indicated the early acquisition of LOH; and (ii) heterogeneous LOH, which were detected in a part of analyzed foci. Homogeneous and heterogeneous LOH were most frequently detected on 17p (92%) followed by 18q (81%), 18p (81%), 5q (61%), 22q (51%), 14q (44%), 15q (41%), 2q (39%), 12q (36%) and 4q (32%). Homogeneous LOH was detected most frequently on 17p (68%) followed by 18p (53%), 18q (53%), 22q (34%) and 12q (27%). The average fractional allelic loss (FAL) for heterogeneous and homogeneous LOH was 0.57 and the average FAL for homogeneous LOH was 0.37.

CONCLUSIONS

Early flat-type colorectal tumors frequently shows the early occurrence of multiple LOH including 17p, 18p, 18q and 22q, which is coupled with additional LOH of other loci either simultaneously or in the early clonal progression phase. The extent and sequences of LOH may be the mechanisms responsible for the aggressive clinical behaviors of these tumors.

Biomechanical comparison of lumbar spine with or without spina bifida occulta. A finite element analysis

STUDY DESIGN

Biomechanical study using finite element model (FEM) of lumbar spine.

OBJECTIVES

Very high coincidence of spina bifida occulta (SBO) has been reported more than in 60% of lumbar spondylolysis. The altered biomechanics due to SBO is one considerable factor for this coincidence. Thus, in this study, the biomechanical changes in the lumbar spine due to the presence of SBO were evaluated.

SETTING

United States of America (USA).

METHODS

An experimentally validated three-dimensional nonlinear FEM of the intact ligamentous L3-S1 segment was used and modified to simulate two kinds of SBO at L5. One model had SBO with no change in the length of the spinous process and the other had a small dysplastic spinous process. Von Mises stresses at pars interarticularis were analyzed in the six degrees of lumbar motion with 400 N axial compression, which simulates the standing position. The range of motion at L4/5 and L5/S1 were also calculated.

RESULTS

It was observed that the stresses in all the models were similar, and there was no change in the highest stress value when compared to the intact model. The range of motion was also similar in all the models. The lumbar kinematics of SBO was thus shown to be similar to the intact model.

CONCLUSION

SBO does not alter lumbar biomechanics with respect to stress and range of motion. The high coincidence of spondylolysis in spines with SBO may not be due to the mechanical factors.

Ethyl esterification of docosahexaenoic acid in an organic solvent-free system with immobilized Candida antarctica lipase

Ethyl docosahexaenoate (EtDHA) is regarded as a potentially useful pharmaceutical substance on account of its beneficial physiological activities. We attempted the ethyl esterification of docosahexaenoic acid (DHA) in an organic solvent-free system using Candida antarctica lipase, which acts strongly on DHA and ethanol. Esterification of 88% was attained by shaking a mixture of DHA/ethanol (1:1, mol/mol) and 2 wt% immobilized C. antarctica lipase at 30 degrees C for 24 h. However, even in the presence of an excess amount of ethanol, the extent of esterification could not be raised above 90%. To attain a higher level of esterification, a two-step reaction was found to be effective. The first step was performed in a mixture of DHA/ethanol (1:1, mol/mol), and the reaction mixture was then dehydrated. In the second step, the resulting mixture was shaken at 30 degrees C for 24 h with 5 molar equivalents of ethanol against the remaining DHA using 2 wt% immobilized lipase. By means of this two-step procedure, 96% esterification was attained. Repetition of the first and second reactions showed that the immobilized lipase was reusable for at least 50 cycles. In addition, DHA remaining in the second-step reaction mixture was removed by a conventional alkali refining process, giving purified EtDHA with a high yield.

Effectiveness of antibiotic combination therapy in patients with active ulcerative colitis: a randomized, controlled pilot trial with long-term follow-up

OBJECTIVE

It is proposed that Fusobacterium varium might be one of the elusive pathogenic factors in ulcerative colitis (UC). Our goal was to assess whether an antibiotic combination therapy against F. varium is effective for induction and maintenance of remission of UC.

MATERIAL AND METHODS

Twenty chronic, active UC patients with F. varium infection were enrolled consecutively and were randomly assigned to receive amoxicillin, tetracycline or metronidazole per os for 2 weeks (treatment group; n=10), or no antibiotics (control group; n=10). F. varium was sensitive to the antibiotics. Symptom assessment, endoscopic and histological evaluations were performed blind before enrollment at 3-5 months and 12-14 months after the treatment. Serum immunoglobulins to F. varium were measured using an enzyme-linked immunosorbent assay (ELISA). Immunohistochemical detection of F. varium in biopsy specimens was carried out using the avidin-biotin complex method.

RESULTS

The clinical activity, endoscopic and histological scores in the treatment group decreased significantly at 3-5 and 12-14 months after the end of treatment compared with those in the control group (p=0.001-0.036). The remission rate in the treatment group was higher than that in the control group (p=0.037). In addition, the titers of antibody to F. varium and the F. varium density in the mucosa decreased at both the short- and long-term follow-ups in the treatment group (p=0.0002-0.049). No serious drug-related toxicity was observed during the trial.

CONCLUSIONS

The 2-week antibiotic combination therapy against F. varium was effective and safe in patients with chronic, active ulcerative colitis in this long-term follow-up study.

Mucosa-associated bacteria in ulcerative colitis before and after antibiotic combination therapy

BACKGROUND

We proposed that Fusobacterium varium is one of the causative agents in ulcerative colitis.

AIM

To examine the efficacy of antibiotic combination therapy against F. varium and to investigate the mucosa-associated bacteria before and after the therapy using a new molecular approach.

METHODS

Twenty patients with ulcerative colitis were randomly assigned into the antibiotic treatment group (amoxicillin, tetracycline and metronidazole for 2 weeks) and no-antibiotics group. Clinical assessment, colonoscopic and histological evaluations were performed at 0 and 3-5 months after the treatment. DNA from mucosal bacteria was isolated from biopsy specimens. We investigated the mucosa-associated bacterial components by terminal restriction fragment length polymorphism with the restriction enzyme HhaI and MspI, and quantified the change in the number of bacteria by real-time polymerase chain reaction. Immunohistochemical detection of F. varium in biopsy specimens was also performed.

RESULTS

After the treatment, the clinical assessment, colonoscopic and histological scores improved in the antibiotic group compared with the control group. Three peaks of terminal restriction fragment length polymorphism decreased after treatment only in the antibiotic group. Eubacterium rectale, Dorea formicigenerans, Clostridium clostridioforme and F. varium were included in these peaks. Based on the real-time polymerase chain reaction study, only F. varium was significantly reduced after treatment. In the immunostaining, post-treatment scores in treatment group were significantly lower than that in control group.

CONCLUSIONS

Antibiotics combination therapy was effective for ulcerative colitis. The number of mucosa-associated F. varium significantly decreased after the treatment.

Biomechanical Rationale of Endoscopic Decompression for Lumbar Spondylolysis as an Effective Minimally Invasive Procedure - A Study Based on the Finite Element Analysis

We evaluated the biomechanical behavior of the endoscopic decompression for lumbar spondylolysis using the finite element technique. An experimentally validated, 3-dimensional, non-linear finite element model of the intact L3 - 5 segment was modified to create the L4 bilateral spondylolysis and left-sided endoscopic decompression. The model of Gill's laminectomy (conventional decompression surgery of the spondylolysis) was also created. The stress distributions in the disc and endplate regions were analyzed in response to 400 N compression and 10.6 Nm moment in clinically relevant modes. The results were compared among three models. During the flexion motion, the pressure in the L4/5 nucleus pulposus was 0.09, 0.09 and 0.16 (MPa) for spondylolysis, endoscopic decompression and Gill's procedure, respectively. The corresponding stresses in the annulus fibrosus were 0.65, 0.65 and 1.25 (MPa), respectively. The stress at the adjoining endplates showed an about 2-fold increase in the Gill's procedure compared to the other two models. The stress values for the endoscopic and spondylolysis models were of similar magnitudes. In the other motions, i. e., extension, lateral bending, or axial rotation, the results were similar among all of the models. These results indicate that the Gill's procedure may lead to an increase in intradiscal pressure (IDP) and other biomechanical parameters after the surgery during flexion, whereas the endoscopic decompression did not change the segment mechanics after the surgery, as compared to the spondylolysis alone case. In conclusion, endoscopic decompression of the spondylolysis, as a minimally invasive surgery, does not alert mechanical stability by itself.

Mass spectrometric investigation of gaseous YbH, YbO and YbOH molecules

The high-temperature gaseous molecules YbH, YbO and YbOH have been identified and their thermochemistry investigated by the Knudsen effusion mass spectrometry technique coupled with a controlled pressure gas inlet system. Solid ytterbium monosilicide and disilicide samples were made to react in the Knudsen cell with H2(g) and H2(g)/O2(g); in these conditions, several gaseous species (Yb, YbO, YbH, YbOH, SiO, SiO2, H2O) were formed under equilibrium conditions. The temperature dependences of the partial pressures of the observed gaseous molecules were analyzed to derive the Yb--X bond energies (X = H, O, OH). Selected values are D0o(Yb--H) = 179.4 +/- 2.0 kJ mol(-1), D0o(Yb--O) = 384 +/- 10 mol(-1) and D0o(Yb--OH) = 322 +/- 12 kJ mol(-1), and Delta(at)H0o(YbOH) = 746 +/- 12 kJ mol(-1). Density functional theory (DFT) calculations were also performed. Experimental and computational results are discussed and compared to previous data when available. The SiO/SiO2 high-temperature gaseous equilibrium was also observed.

Frequent hypermethylation of RASSF1A in early flat-type colorectal tumors

Flat colorectal tumors, characterized by high-grade dysplasia from early small flat mucosal lesions, exhibit a relatively aggressive clinical behavior and are known for their infrequent K-ras mutations. In this study, we investigated the methylation status of the RASSF1A promoter in association with 3p LOH and K-ras mutations in 48 flat colorectal tumors (39 early carcinomas and nine intramucosal high-grade dysplasias). RASSF1A hypermethylation was detected in 39 of 48 (81.3%) tumors and RASSF1A methylation was also detected in 19 of 39 (49%) normal colonic mucosal tissues. 3p21.3 LOH was detected in 20 of 42 (47.6%) cases, but RASSF1 methylation was detected in cases with LOH (14 cases) and retention of 3p21.3 (20 cases). K-ras mutations were detected in seven of 48 (14.6%) tumors and the concordant occurrence of K-ras mutation and RASSF1A methylation was detected in three of 48 cases (6.3%). Overall, there was a statistically significant mutually exclusive relationship between K-ras mutations and RASSF1A methylation. In conclusion, promoter hypermethylation of RASSF1A is a frequent event and may start early in the background normal mucosa in this tumor type. An alternative cascade of abnormalities in RAS transduction pathways may be responsible for the flat morphology and aggressive nature of flat colorectal neoplasms.

Second-line treatment for Helicobacter pylori infection in Japan: proton pump inhibitor-based amoxicillin and metronidazole regimen

BACKGROUND

Recent studies have reported that proton pump inhibitor (PPI)/amoxicillin (A) metronidazole (M) therapy for Helicobacter pylori infection provides a sufficient cure rate in Japan in patients who have failed first-line treatment with PPI/amoxicillin and clarithromycin (AC). To validate the efficacy of this regimen as second-line therapy, our experience with second-line treatment using a PPI/AM regimen was reviewed.

METHODS

We analyzed data on 151 patients who had been prescribed a 10-day PPI/AM re-treatment regimen after eradication failure of 1 to 2 weeks' first-line PPI/AC therapy. The PPI/AM regimen was given according to results of susceptibility testing (S+) in 31 patients. The group that had undergone susceptibility testing was further divided into two subgroups according to dosage: standard dose of omeprazole (O)/AM (n = 11) and double dose of lansoprazole (L)/AM (n = 20). The PPI/AM regimen was given without susceptibility testing (S-) to 120 patients. These patients were also divided into two subgroups according to whether they received omeprazole or lansoprazole: OAM (n = 61) and LAM (n = 59). Cure rates and adverse effects in each group were analyzed.

RESULTS

The intention-to-treat (ITT)-based cure rate with/without susceptibility testing was 93.5% (95% confidence interval [CI], 79%-99%) and 87.5% (95% CI, 80%-93%), respectively (not significant [NS]). The ITT-based cure rate in S+/S- for OAM and S+/S- for LAM was 90.9% (95% CI, 59%-100%)/82% (95% CI, 70%-91%), and 95% (95% CI, 75%-100%)/93.2% (95% CI, 84%-98%), respectively (NS). Adverse effects were seen in 26.3% and 32.5% of patients in the OAM group and the LAM group, respectively (NS).

CONCLUSIONS

The 10-day PPI/AM re-treatment regimen is safe and effective, suggesting its usefulness as second-line treatment in Japan in patients who have failed initial treatment with the PPI/AC regimen.

Improvement in serum pepsinogens and gastrin in long-term monitoring after eradication of Helicobacter pylori: comparison with H. pylori-negative patients

BACKGROUND

A decrease in pepsinogen and gastrin levels 1-3 months after Helicobacter pylori eradication is well known. However, few data are available on the long-term progression of these decreases beyond 1 year after eradication, and there has been no investigation into whether pepsinogen and gastrin levels return to normal levels as defined by data from H. pylori-negative patients with dyspepsia.

AIM

We studied the effect of H. pylori eradication on pepsinogen and gastrin levels for more than 1 year, and compared levels to those in H. pylori-negative patients with dyspepsia. We also investigated the effect of H. pylori eradication on the course of atrophic corpus gastritis as reflected by histology, and on PGI levels and PG I/II ratio.

METHODS

We enrolled 172 H. pylori-positive patients with dyspepsia who had undergone successful eradication therapy of more than 1 year's duration and 101 non-treated H. pylori-negative patients with dyspepsia. H. pylori status was assessed at entry and at each endoscopy after eradication by culture, histological results, the rapid urease test and the urea breath test. In both groups, patients were evaluated for fasting serum pepsinogen I and II and gastrin using a radioimmunoassay technique, and underwent detailed histological assessment according to the updated Sydney System.

RESULTS

In the H. pylori-negative patients, mean serum pepsinogen I and II, I/II ratio and gastrin levels were 52.6 +/- 20.8 ng/mL, 9.2 +/- 4.2 ng/mL, 6.0 +/- 1.7 and 53.5 +/- 29.2 pg/mL, respectively. In H. pylori-positive patients with long-term eradication, pepsinogen I and II, I/II ratio and gastrin levels were 81.3 +/- 46.6 ng/mL, 25.9 +/- 17.1 ng/mL, 3.4 +/- 1.3 and 131.9 +/- 130.8 pg/mL, respectively, before treatment. At 1-3 months after eradication, serum pepsinogen I and II levels in the H. pylori-positive patients decreased to levels similar to those in the negative patients, whereas pepsinogen I/II ratio and gastrin levels remained lower and higher, respectively, than in the negative patients. Serum pepsinogen I/II ratio and gastrin levels then became similar between the groups at 12-15 months after eradication. In histological findings, inflammation and neutrophil activity decreased by 1-3 months, and atrophy in the corpus and metaplasia in the antrum decreased by 12-15 months.

CONCLUSION

The results suggest that atrophic corpus gastritis and superficial gastritis are reversible, as indicated by both histological and serological findings in a long-term follow-up study.

Endoscopic, histological and serologic findings of gastric hyperplastic polyps after eradication of Helicobacter pylori: comparison between responder and non-responder cases

BACKGROUND

Evidence indicates that eradication of Helicobacter pylori leads to the disappearance of hyperplastic polyps in the stomach. However, there are some exceptions. We have compared endoscopic and serologic findings of responder and non-responder cases with hyperplastic polyps to try to identify the cause(s), other than H. pylori infection, of the formation or growth of gastric hyperplastic polyps.

METHODS

We retrospectively studied 33 patients whose hyperplastic polyps disappeared after eradication of H. pylori and 10 patients whose hyperplastic polyps did not disappear after eradication. The patients were examined both endoscopically and serologically before, 1-3 months after and 12-15 months after the eradication.

RESULTS

The responder and non-responder groups were similar with respect to age, sex, coexisting diseases, and histologic findings. The number and maximum size of polyps tended to be larger before treatment in the non-responder group than in the responder group. The serum gastrin level was higher in the non-responder group than in the responder group before, 1-3 months after and 12-15 months after the eradication (p=0.0096, p>0.2, p=0.0014). On histologic examination, similar reductions in the degree of inflammatory cell infiltration in the gastric mucosa of the antrum and body were seen in both the responder and non-responder groups. In the non-responders, the size and numbers of the polyps regressed in 5 of the 10 patients. The score of glandular atrophy in the antrum and the serum gastrin levels in the non-regressed cases was higher than those in the regressed cases at 1-3 and 12-15 months after eradication.

CONCLUSION

Persistent high gastrin levels were found in the non-responder cases with gastric hyperplastic polyps.

Effects of active recovery under a decreasing work load following intense muscular exercise on intramuscular energy metabolism

The effect of active recovery at a decreasing % of MVC following intense muscular exercise on intramuscular pH was investigated in vivo using 31P-MRS. Seven healthy men participated, and their right wrist flexor muscle group was examined. The subjects were asked to flex their right wrist at 60 % of the maximum voluntary contraction (MVC) every 2 s until the intracellular pH in the wrist flexor muscle decreased to 6.4. After the exercise period, the subjects underwent active or passive recovery for 10 min. For the active recovery (AR), the subject was asked to continue exercising at a decreasing % of MVC, decreasing from 25 to 5 % MVC every two min during AR. 31P-MR-spectra were obtained throughout the experiments, and from the spectra the intracellular pH (pHi) was calculated as an indicator of intracellular events. AR data were compared to data collected during passive recovery (PR). During AR, the pHi increased immediately after the exercise period; whereas in that of PR, it did not recover within 5 minutes after exercise. The results suggested that mild exercise was an effective manoeuver to promote recovery from intramuscular metabolic acidosis.