Narrow band imaging for detecting superficial squamous cell carcinoma of the head and neck in patients with esophageal squamous cell carcinoma

BACKGROUND AND STUDY AIMS

Narrow band imaging combined with magnifying endoscopy (NBI-ME) is useful for the detection of superficial squamous cell carcinoma (SCC) within the oropharynx, hypopharynx, and oral cavity. The risk of a second primary SCC of the head and neck is very high in patients with esophageal SCC. This prospective study evaluated the detection rate of superficial SCC within the head and neck region (superficial SCCHN) with NBI-ME in patients with esophageal SCC.

PATIENTS AND METHODS

Between March 2006 and February 2008, 112 patients with a current or previous diagnosis of esophageal SCC were enrolled. All patients underwent endoscopic screening of the head and neck by NBI-ME. The primary end point was the detection rate for superficial SCCHN. Secondary end points were to compare demographic characteristics between patients with and without superficial SCCHN and to assess the clinical course of patients with superficial SCCHN.

RESULTS

The detection rate for superficial SCCHN was 13 % (15/112). The prevalence of multiple Lugol-voiding lesions, observed endoscopically throughout the esophageal mucosa after application of Lugol dye solution, was significantly higher in patients with superficial SCCHN than in those without (100 % vs. 24 %, P < 0.0001). Minimally invasive curative treatment with organ preservation was feasible without severe complications in patients with superficial SCCHN after curative treatment of esophageal SCC.

CONCLUSIONS

In patients with esophageal SCC, NBI-ME is useful for detecting superficial SCCHN, thereby facilitating minimally invasive treatment.

Visceral fat accumulation is a significant risk factor for white matter lesions in Japanese type 2 diabetic patients

BACKGROUND

The presence of white matter lesions (WML) is an important prognostic factor for the development of stroke. The elevated visceral fat accumulation (VFA) has been reported to be closely related to the development of atherosclerosis. This preliminary study was therefore designed to test the hypothesis that the presence of WML correlates with VFA and insulin resistance in type 2 diabetic patients not receiving insulin treatment.

MATERIAL AND METHODS

Based on brain magnetic resonance imaging (MRI), 95 type 2 diabetic patients were divided into two groups: WML-positive group (aged 59 +/- 7 years, mean +/- SD n = 37) and WML-negative group (aged 58 +/- 5, years, n = 58). The level of blood glucose was assessed by fasting plasma glucose (FPG), fasting immunoreactive insulin, homeostasis model assessment (HOMA) index, and haemoglobin A1c. The fat distribution was evaluated by measuring the visceral fat accumulation by abdominal computerized tomography at the umbilical level.

RESULTS

The body mass index was higher in the WML-positive group than in the WML-negative group (P < 0.005). Plasma levels of triglycerides were higher while high-density lipoprotein cholesterol was lower in the WML-positive group than in the WML-negative group (P < 0.05 and P < 0.01, respectively). FPG (P < 0.01), insulin concentrations (P < 0.0001), HOMA index (P < 0.0001) and VFA (<0.0001) levels were higher in the WML-positive group than in the WML-negative group. Multivariate logistic analysis revealed that WML was independently predicted by the high VFA and insulin resistance (P < 0.001, P < 0.0001, respectively).

CONCLUSIONS

The results of this preliminary study indicate that the presence of WML was associated with the high VFA and insulin resistance in Japanese patients with type 2 diabetes mellitus. Further larger cohort studies are warranted to confirm these findings.

Pioglitazone shift circadian rhythm of blood pressure from non-dipper to dipper type in type 2 diabetes mellitus

BACKGROUND

Insulin resistance significantly correlated with a non-dipper type of essential hypertension. Thiazolidinediones (TZD), oral hypoglycaemic agents that act as insulin sensitizers, have been demonstrated in multiple in vivo and in vitro studies to possess antihypertensive properties. This study examined the efficacy of TZD therapy with pioglitazone at transforming the circadian rhythms of blood pressure from a non-dipper to a dipper type.

MATERIALS

We examined 31 patients with type 2 diabetes mellitus during both a baseline period and a period of treatment with pioglitazone. Patients received 15 mg day(-1) pioglitazone for four weeks and 30 mg day(-1) for 12 weeks. Twenty-four hour ambulatory blood pressure monitoring (ABPM) and laboratory data (blood tests for cardiovascular risk factors) were obtained at the beginning and end of the study.

RESULTS

In non-dippers (n = 16), but not dippers (n = 15), we observed a significant interaction between pioglitazone therapy and nocturnal falls in systolic and diastolic blood pressure. This examination indicated that the magnitude of the nocturnal blood pressure fall was affected by pioglitazone therapy. In non-dippers, but not dippers, a significant correlation was observed between the percent decrease in nocturnal BP and the homeostasis model assessment (HOMA) index (r = 0.774, P = 0.0007).

CONCLUSIONS

The present study demonstrated that pioglitazone can restore the nocturnal BP declines in parallel to reductions in the HOMA index, suggesting that insulin resistance may play an important role in the genesis of circadian BP rhythms. TZD-based treatment may thus have the additional therapeutic advantage of reducing the risk of cardiovascular complications by transforming the circadian rhythm of BP.

Hippocalcin protects hippocampal neurons against excitotoxin damage by enhancing calcium extrusion

Hippocalcin, which is a member of the neuronal calcium-sensor protein family, is highly expressed in hippocampal pyramidal cells. Recently, it was demonstrated that hippocalcin deficit caused an increase in neuronal cell death in the field CA3 of Ammon's horn (CA3) region of the hippocampus following the systemic injection of kainic acid. Treatment with kainic acid results in seizure-induced cell death in CA3. In the present study, we injected quinolinic acid, which is an N-methyl-d-aspartate receptor agonist, into the hippocampal field CA1 of Ammon's horn (CA1) region in hippocalcin-knockout (-/-) mice, a procedure which mimics transient ischemia. Although significant pyknotic changes were observed at the injected site in wild-type (+/+) mice 24 h after injection, the area of pyknotic cells extended throughout the hippocampus in -/- mice. The quantification of cell numbers in Nissl-stained sections indicated that the cell damage in -/- mice was more severe than that in +/+ mice. The density of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labeling-positive cells roughly paralleled that of Nissl-stained pyknotic cells. Primary cultures of hippocampal neurons showed that the number of surviving neurons from -/- mice after 7 days in culture was smaller than the number from +/+ mice. The measurement of intracellular calcium concentrations in single cells revealed that the calcium extrusion from -/- neurons was slower than that from +/+ neurons. The involvement of hippocalcin in the upkeep of calcium extrusion was confirmed using hippocalcin-expressing COS7 cells. These results suggest that hippocalcin plays an important role in calcium extrusion from neurons and, in turn, helps to protect them against calcium-dependent excitotoxin damage in the hippocampus.

Disinhibition of somatosensory evoked potential recovery in alcoholics

The pathogenesis of cognitive impairment in alcoholics remains unclear. Previous studies suggested that diffuse white matter atrophy is associated with cognitive impairment in alcoholics. To elucidate this issue, the present study evaluated alcoholics with cognitive impairment using the somatosensory evoked potential (SEP) recovery method, which is suitable for detecting subtle dysfunction at the cortical level. Subjects comprised 12 alcoholics with mild cognitive impairment [Mild group: Mini Mental State Examination Score (MMSE), > or =24; mean, 27.9 +/- 1.6], 12 alcoholics with moderate to severe cognitive impairment (Moderate group: MMSE score, < 24; mean, 21.0 +/- 2.5) and 12 normal subjects (Control group). SEP was recorded from the hand sensory area contralateral to the median nerve stimulated at the wrist. Single-pulse or paired-pulse stimuli at various interstimulus intervals (10-300 ms) were administered. Recovery functions of N9 (a peripheral nerve component), N20, N20-P25 and P25-N33 (cortical components) were studied. N20 recovery curves of both alcoholic groups were less suppressive than those of Controls, and P25-N33 recovery curves of the Moderate group were more excitatory than those of the Mild or Control groups. A disinhibited recovery pattern of N20 indicates subcortical dysfunction, and a disinhibited pattern of P25-N33 would be induced by cortical dysfunction. Therefore, subcortical dysfunction indicated by an abnormal N20 recovery pattern may contribute to the early cognitive impairment of alcoholics, whilst the cortical dysfunction indicated by an abnormal P25-N33 recovery pattern may contribute to the later cognitive impairment of alcoholics.

Smoking is associated with insulin resistance and cardiovascular autonomic dysfunction in type 2 diabetic patients

BACKGROUND

Smoking and cardiovascular autonomic dysfunction are associated with high mortality in type 2 diabetic patients. This study tested the hypothesis that smoking is associated with insulin resistance/hyperinsulinaemia and cardiovascular autonomic dysfunction in type 2 diabetic patients who are not treated with insulin.

MATERIALS AND METHODS

The study patients were 22 current smokers with type 2 diabetes mellitus (age: 57 +/- 5 years, mean +/- SD) and 30 age-matched never-smoked patients with type 2 diabetes mellitus (control group, 57 +/- 8 years). The quality of blood glucose was assessed by fasting plasma glucose (FPG), fasting immunoreactive insulin (F-IRI), homeostasis model assessment (HOMA) index and haemoglobin A1c (HbA1c). The severity of smoking status was expressed by the Brinkman index, which is calculated as number of cigarettes per day multiplied by years of smoking. Cardiovascular autonomic function was assessed by baroreflex sensitivity (BRS), heart-rate variability, plasma norepinephrine concentration and cardiac (123)I-metaiodobenzylguanidine (MIBG) scintigraphic findings.

RESULTS

Baroreflex sensitivity was lower in the current smokers group than in the never-smoked group (P < 0.05). Early and delayed (123)I-MIBG myocardial uptake values were lower (P < 0.05, and P < 0.01, respectively) and the percentage washout-rate of (123)I-MIBG was higher (P < 0.0001) in the current smokers group than in the never-smoked group. Fasting immunoreactive insulin (F-IRI) concentration (P < 0.0001) and the homeostasis model assessment (HOMA) index (P < 0.0001) were higher in the current smokers group than the never-smoked group. Multiple logistic regression analysis revealed that smoking was independently predicted by F-IRI and the percentage washout-rate of (123)I-MIBG.

CONCLUSIONS

The results of the study suggested that smoking was associated with cardiovascular autonomic dysfunction and hyperinsulinaemia and that F-IRI and the percentage washout-rate of (123)I-MIBG were independent predictors of smoking in these Japanese patients with type 2 diabetes mellitus.

PDGF receptor tyrosine kinase inhibitor suppresses mesangial cell proliferation involving STAT3 activation

Proliferation of mesangial cells is a hallmark of glomerular disease, and understanding the regulatory mechanisms is critically important. The purpose of this study was to examine the relationship between mesangial cell proliferation and phosphorylated signal transducer and activator of transcription (STAT) 3 and to determine whether the PDGF receptor tyrosine kinase inhibitor STI 571 inhibited mesangial cell proliferation via modulation of STAT3. In this study, we investigated for the first time, the glomerular expression of phosphorylated STAT3 in paraffin sections from animals with experimental mesangial proliferative glomeronephritis. Phosphorylated STAT3 colocalized with many proliferating mesangial cells. We also demonstrated that treatment with STI 571 reduced mesangial cell proliferation and phosphorylated STAT3 signalling both in vitro and in vivo. In vivo, STI 571 treatment reduced the number of glomerular mesangial cells positive for both phosphorylated STAT3 and proliferating cell nuclear antigen. In summary, phosphorylated STAT3 is strongly expressed during mesangial cell proliferation and STI 571 induced suppression of mesangial cell proliferation involves inhibition of phosphorylated STAT3 signalling.

Usefulness of FDG-PET in predicting the prognosis of advanced pancreatic carcinoma with chemotherapy

14043

Background: 18F-fluorodeoxyglucose (FDG) PET is a new diagnostic imaging technique that takes advantage of increased glucose metabolism by the tumor cells. High uptake of FDG is reportedly associated with poor survival in head and neck cancer (Heikki et al., 1997, Nuclear Oncology). FDG uptake diminishes with elevated levels of plasma glucose. We herein evaluated the usefulness of FDG-PET in predicting the prognosis of advanced pancreatic carcinoma (APC). Methods: FDG-PET was performed on 32 consecutive patients with APC between July 2001 and April 2004. The patients fasted for at least 5 hr before the study. The plasma glucose level was controlled under 150 mg/dl by using oral antidiabetic or insulin therapy in advance. FDG-PET images were acquired 45 min after intravenous injection of FDG. We did not measure the plasma glucose level directly before imaging. The FDG uptake in the primary tumor was quantitated as the standardized uptake value (SUV), and the maximum SUV (SUVmax) was measured in the regions of interest. All of the 32 APC patients received chemotherapy (26: gemcitabine, 1: gemcitabine + UFT, 5: TS-1). We analyzed the correlation between SUVmax and the overall survival. Then, we excluded the diabetics (n = 8) and compared SUV in the non-diabetic patients (n = 24). The overall survival curve was plotted according to the method of Kaplan and Meier. The difference in the overall survival was calculated using the log-rank test, and a multivariate analysis was conducted. Results: 32 patients were examined. All cases showed FDG uptake in the pancreatic tumor (SUVmax ranged from 2.73 to 9.67). The overall survival ranged from 38 to 945 days with a median of 261 days.These patients were classified into two groups at a median SUVmax value of 4.81. There was no significant difference in the overall survival between these two groups (p > 0.05). The non-diabetic patients (n = 24) were classified into two groups at a median SUVmax value of 5.51. The high SUVmax group had shorter overall survival than the low SUVmax group (p = 0.039). The multivariate analysis using Cox hazard model also revealed that SUVmax was a significant, independent factor that influenced the survival (p = 0.043) in the non-diabetic patients. Conclusions: FDG-PET may be a useful modality in determining the prognosis of APC.

No significant financial relationships to disclose.

Efficacy of local dipyridamole therapy in a porcine model of arteriovenous graft stenosis

Perivascular delivery of antiproliferative drugs has been proposed as an approach to prevent neointimal hyperplasia associated with hemodialysis polytetrafluoroethylene (PTFE) grafts. We examined this approach to deliver dipyridamole in a porcine graft model. PTFE grafts were implanted between the carotid artery and external jugular vein bilaterally in pigs. During the surgery or 1 week post-graft placement, dipyridamole (0.26-52 mg) alone or incorporated in microspheres was mixed with an injectable polymeric gel and applied to the graft-arterial and graft-venous anastomoses on one side, whereas the contralateral control graft received no treatment. Three or four weeks after operation, the grafts and adjacent vessels were explanted en bloc and cross-sections of the anastomoses were examined histologically. The degree of neointimal hyperplasia was quantified by planimetry. In separate experiments, dipyridamole was extracted from the explanted tissues and assayed by spectrofluorometry. The normalized median hyperplasia areas of the treated and control graft-venous anastomoses were 0.45 (25th-75th percentile, 0.30-0.86) and 0.24 (0.21-0.30), respectively (N=7; P=0.08). The median hyperplasia areas of the treated and control graft-arterial anastomoses were 0.12 (0.07-0.39) and 0.11 (0.09-0.13), respectively (N=7; P=0.31). The dipyridamole levels in the vascular walls around the anastomoses were at or above the in vitro inhibitory concentrations for approximately 3 weeks. These results suggest that the local perivascular sustained delivery of dipyridamole, even at high dosages, was ineffective in inhibiting neointimal hyperplasia associated with PTFE grafts in a porcine model.

Angiopoietin 2 displays a vascular endothelial growth factor dependent synergistic effect in hepatocellular carcinoma development in mice

BACKGROUND

Orchestration of two major classes of angiogenic factors-namely, vascular endothelial growth factor (VEGF) and angiopoietin 2 (Ang-2)-has been shown to play a pivotal role in tumour angiogenesis, including hepatocellular carcinoma (HCC). However, few studies have focused on the direct interaction of these factors on in vivo tumour development and angiogenesis.

AIM

To examine the interaction between both factors in murine HCC.

METHODS

We examined the combination effect of VEGF and Ang-2 overexpression by means of a combination of a retroviral tetracycline (tet) regulated gene manipulating system in vivo, by providing tet in the drinking water, and a conventional plasmid gene expression system.

RESULTS

Neither Ang-2 nor VEGF overexpression induced proliferation of HCC cells in vitro. In vivo, although overexpression of Ang-2 did not increase tumour development, simultaneous expression of Ang-2 and VEGF synergistically augmented tumour growth and angiogenesis in murine HCC. Ang-2 plus VEGF induced tumour development was markedly attenuated by treatment with neutralising monoclonal antibodies against VEGF receptors. Ang-2 plus VEGF overexpression significantly increased the activities of matrix metalloproteinase (MMP)-2 and MMP-9 in the tumour. Suppression of intratumoral VEGF almost completely abolished this augmentation of MMPs.

CONCLUSIONS

These results suggest that Ang-2 synergistically augments VEGF mediated HCC development and angiogenesis. This proangiogenic activity was exerted only in the presence of VEGF, at least partly mediated via induction of MMP-2 and MMP-9 in the tumour.

Cognitive impairment and diffuse white matter atrophy in alcoholics

OBJECTIVE

Diffuse brain white matter atrophy is often seen in chronic alcoholics, but its relation with cognitive impairment remains to be solved. In order to address this issue, in alcoholics with cognitive impairment at different levels, we studied relations of the central sensory conduction time (CSCT) or brain magnetic resonance imaging (MRI) findings with the cognitive function.

METHODS

Subjects were 35 alcoholics with mild cognitive impairment (mini-mental state examination score, MMSE, >/=24; mean+/-SD, 27.7+/-1.9), 12 with moderate to severe cognitive impairment (MMSE<24; 20.3+/-2.7), 15 with Alzheimer's disease (AD) (MMSE, 18.9+/-4.3) (disease control) and 20 healthy volunteers (MMSE, 28.5+/-1.6) (normal control). Median nerve SEPs were recorded in the all subjects, and the latencies and amplitudes of their N9, N11, P13/14, N20 and P25 components were measured. The ventriculocranial ratio (VCR) and the width of cortical sulci were measured on MRIs. These physiological parameters and MRI findings were compared between the 4 groups of the subject, and correlations between those all features were also analyzed.

RESULTS

CSCT and VCR were significantly greater in alcoholics with moderate to severe cognitive impairment than those in the other 3 groups. Pearson's product-moment correlation analyses of the alcoholics disclosed that both the CSCT and VCR had significant negative correlations with the MMSE score. Moreover, the CSCT and VCR were positively correlated.

CONCLUSIONS

Both physiological and morphological estimates of the white matter function (CSCT and VCR) had a significant correlation with the cognitive dysfunction.

SIGNIFICANCE

The diffuse white matter atrophy may be one of the factors causing cognitive impairment in chronic alcoholics.

Crystallization and preliminary X-ray diffraction analysis of two lysinal derivatives of Achromobacter protease I

Two crystal forms of lysinal derivatives of Achromobacter protease I have been obtained. The first, modified by benzyloxycarbonyl-Val-lysinal crystallizes in the monoclinic space group P2(1) with unit-cell dimensions of a = 39.6, b = 71.2, c = 45.6 A and beta = 98.4 degrees. The second, modified by benzyloxycarbonyl-Leu-Leu-lysinal crystallizes in the orthorhombic space group I222 (or I2(1)2(1)2(1)) with unit-cell dimensions of a = 98.7, b = 102.2 and c = 55.8 A. The space groups and the unit-cell dimensions of the present two lysinal derivatives are different to those of the protease and TLCK- modified one. The space group of the protease is P1 with cell dimensions a = 39.53, b = 40.34, c = 43.92 A, alpha = 114.81, beta = 113.75 and gamma = 74.00 degrees and that of the TLCK-modified one is also P1 with cell dimensions of a = 37.30, b = 42.74, c = 48.02 A, alpha = 120.10, beta = 112.81 and gamma = 68.54 degrees. Diffraction to 1.9 A resolution for the Val-lysinal modified crystal and to 2.2 A resolution for the Leu-Leu-lysinal modified crystal has been observed using a rotating-anode X-ray generator. Full structure determinations of these lysinal-modified protease crystals may lead to an understanding of the molecular basis of enzyme-substrate interactions in the catalytic process of this protease.

Hippocalcin-deficient mice display a defect in cAMP response element-binding protein activation associated with impaired spatial and associative memory

Hippocalcin is a member of the neuronal calcium sensor (NCS) protein family that is highly expressed in hippocampal pyramidal cells and moderately expressed in the neurons of cerebral cortex, cerebellum and striatum. Here we examined the physiological roles of hippocalcin using targeted gene disruption. Hippocalcin-deficient (-/-) mice displayed no obvious structural abnormalities in the brain including hippocampal formation at the light microscopic level. Deletion of hippocalcin did not result in up-regulation of the hippocalcin-related proteins; neural visinin-like Ca(2+)-binding proteins (NVP) 1, 2, and 3. The synaptic excitability of hippocampal CA1 neurons appeared to be normal, as estimated by the shape of field excitatory postsynaptic potentials elicited by single- and paired-pulse stimuli, and by tetanic stimulation. However, N-methyl-d-aspartate stimulation- and depolarization-induced phosphorylation of cAMP-response element-binding protein (CREB) was significantly attenuated in -/- hippocampal neurons, suggesting an impairment in an activity-dependent gene expression cascade. In the Morris water maze test, the performance of -/- mice was comparable to that of wild-type littermates except in the probe test, where -/- mice crossed the previous location of the platform significantly less often than +/+ mice. Hippocalcin-deficient mice were also impaired on a discrimination learning task in which they needed to respond to a lamp illuminated on the left or right side to obtain food reinforcement. No abnormalities were observed in motor activity, anxiety behavior, or fear learning. These results suggest that hippocalcin plays a crucial role in the Ca(2+)-signaling pathway that underlies long-lasting neural plasticity and that leads to spatial and associative memory.

Evaluation of bioactive saponins and triterpenoidal aglycons for their binding properties on human endothelin ETA and angiotensin AT1 receptors

Different types of triterpenes including saponins and aglycons were evaluated for their ability to inhibit [3H] BQ-123 and [3H] angiotensin II binding to the human endothelin 1 ETA and angiotensin II AT1 receptors, respectively. Selectivity for only one of the two receptors was exhibited by asiatic acid and its saponins (ETA) and oleanolic acid (AT1). To a lesser extent betulinic acid, beta-amyrin and friedelin also showed selectivity for the ETA receptor. To address the question whether the effect of saponins on cell membranes might interfere with the normal binding of specific radioligands to their receptors, the activity of saponins with different haemolytic properties were compared. Highly haemolytic saponins such as alpha-hederin and beta-escine showed partial (60%) inhibition of radioligand-binding to the ETA receptor and complete inhibition (100%) to the AT1 receptor. Moreover, the haemolytically inactive kryptoescine, at the same concentration, caused complete inhibiton of radioligand-binding to both receptors, indicating that inhibition of receptor binding was not related to the membrane-interacting properties of saponins.

Endoscopic retreatment of recurrent choledocholithiasis after sphincterotomy

BACKGROUND

Endoscopic sphincterotomy (ES) carries a substantial risk of recurrent choledocholithiasis but retreatment with endoscopic retrograde cholangiopancreatography (ERCP) is safe and feasible. However, long term results of repeat ERCP and risk factors for late complications are largely unknown.

AIMS

To investigate the long term outcome of repeat ERCP for recurrent bile duct stones after ES and to identify risk factors predicting late choledochal complications.

METHODS

Eighty four patients underwent repeat ERCP, combined with ES in 69, for post-ES recurrent choledocholithiasis. Long term outcomes of repeat ERCP were retrospectively investigated and factors predicting late complications were assessed by multivariate analysis.

RESULTS

Complete stone clearance was achieved in all patients. Forty nine patients had no visible evidence of prior sphincterotomy. Two patients experienced early complications. During a follow up period of 2.2-26.0 years (median 10.9 years), 31 patients (37%) developed late complications, including stone recurrence (n = 26), acute acalculous cholangitis(n = 4), and acute cholecystitis (n = 1). There were neither biliary malignancies nor deaths attributable to biliary disease. Multivariate analysis identified three independent risk factors for choledochal complications: interval between initial ES and repeat ERCP < or =5 years, bile duct diameter > or =15 mm, and periampullary diverticulum. Choledochal complications were successfully treated with repeat ERCP in 29 patients.

CONCLUSIONS

Choledochal complications after repeat ERCP are relatively frequent but are endoscopically manageable. Careful follow up is necessary, particularly for patients with a dilated bile duct, periampullary diverticulum, or early recurrence. Repeat ERCP is a reasonable treatment even for recurrent choledocholithiasis after ES.