Trend in the prevalence of atrial fibrillation 7 years after the Great East Japan Earthquake

Background

The age-adjusted prevalence rate of atrial fibrillation (AF) had kept increasing until 2-year after the Great East Japan Earthquake (reported in ESC2017). Whether the elevated prevalence was tentative or not has not been sufficiently elucidated yet.

Methods

Community dwellers aged 40 to 74 years living in Iwate Prefecture who underwent annual health checkups (2010 (n=17490), 2011 (n=174236), 2012 (n=183612), 2013 (n=188429), 2014 (n=188424), 2015 (n=193610), 2016 (n=194882), 2017 (n=195428) account for approximately 30% of total population) were enrolled. Participants were divided into two age categories (40–64, 65–74 years). Direct age-adjusted prevalence rate of AF in each year was estimated using the 2010 population as the reference.

Result

Data are shown in the figure.

Conclusion

Prevalence rates of AF increased only in elderly people for up to 3 years after the disaster. This indicated that accelerated development of AF in elderly people due to stressful life after the disaster would not end within a short term and lasted at least 3 years after the disaster.

Figure 1

Funding Acknowledgement

Type of funding source: None

P3772Risk factors for future development of atrial fibrillation are not evident among apparently healthy individuals with paroxysmal atrial fibrillation

Background

Atrial fibrillation (AF) is one of the important factors of cardiovascular morbidity and mortality and to find not only patients with persistent AF but also individuals with paroxysmal AF among apparently healthy people is a crucial strategy for decreasing number of patients with serious cardio-embolic stroke. However, screening ability using previously known risk factors for future development of AF has not been examined in individuals with paroxysmal AF.

Methods

A total of 59730 male individuals, aged 40 years or older who underwent multiple comprehensive physical check-ups including 12 lead electrocardiogram (ECG) from 2012 to 2015 were enrolled. Persistent AF was defined a case that consecutively manifested AF till the last checkup. Paroxysmal AF was defined as a case who transiently manifested AF in each of the checkup and subsequently manifested sinus rhythm at the last checkup. Non-AF was defined as a case that never manifested AF in any of checkup. Age-adjusted prevalence rates and their 95% confidence intervals of known-risk factors in the first survey were estimated by logistic regression analysis separately by the three groups (non-AF (n=58602), paroxysmal AF (n=392) and persistent AF (736)).

Results

Age-adjusted prevalence rates (95% confidence interval) of risks factors for AF are shown in the table. Already known risk factors were evidently manifested in persistent AF group, however, prevalence rates of these factors in paroxysmal AF group were not different from the rates in non-AF group.

Conclusion

The repeated measurements of ECG study indicated that individuals who would develop paroxysmal AF in the near future did not have typical risk factors for AF and a screening test using risk factors for AF have no chance to find a high-risk individual for paroxysmal AF.

A study on fluoroscopic images in exposure reduction techniques - Focusing on the image quality of fluoroscopic images and exposure images

The quality of the present day fluoroscopic images is sufficiently high for use as exposure images depending on the environment where the fluoroscopic images are recorded. In some facilities which use fluoroscopic images as exposure images they are recorded with a radiological x‐ray diagnostic device equipped with a fluoroscopic storage function. There are, however, cases where fluoroscopic images cannot be used as exposure images because the quality of the fluoroscopic image cannot be assured in the environment where the fluoroscopic images are recorded. This poses problems when stored fluoroscopic images are used in place of exposure images without any clearly established standard. In the present study, we establish that stored fluoroscopic images can be used as exposure images by using gray values obtained from profile curves. This study finds that replacement of stored fluoroscopic images with exposure images requires 20.1 or higher gray scale value differences between the background and signal, using a 20 cm thick acrylic phantom (here an adult abdomen as representing the human body) as the specific geometry. This suggests the conclusion that the gray value can be considered a useful index when using stored fluoroscopic images as exposure images.

Abstract P6-09-25: Circulating tumor cell clusters-associated gene plakoglobin is a novel prognostic predictor in patients with breast cancer

Background: Accumulating evidence shows that circulating tumor cells (CTC) are linked to metastatic relapse and are regarded as a prognostic marker for human cancer. It was reported that CTC clusters (CTCc) have more metastatic potential than single CTC. Lately, studies also show that the high expression of plakoglobin, a cell adhesion protein, within the primary tumor are positively associated with CTCc in breast cancer patients. In addition, it is thought that insufficient expression of plakoglobin could promote epithelial-mesenchymal transition (EMT). In this study, we investigated the correlation between plakoglobin expression and survival of breast cancer.

Materials and Methods:A total of 126 patients with resectable early-stage breast cancer were treated with neoadjuvant chemotherapy (NAC). All patients received a standardized protocol of NAC consisting of four courses of FEC100 (500 mg/m2 fluorouracil, 100 mg/m2 epirubicin, and 500 mg/m2 cyclophosphamide) every 3 weeks, followed by 12 courses of 80 mg/m2 paclitaxel administered weekly. The expression of plakoglobin were identified by immunohistochemical staining properties in cell membrane. Staining with plakoglobin (clone 4C12) was scored according to the percentage of cells that stained positively: low, 0-25%; medium, 26-75%; high, >75%. We investigated the correlation between the plakoglobin expression in primary tumor specimen and clinical outcomes including overall-survival (OS), disease-free-survival (DFS), distant-metastasis-free-survival (DMFS), the efficacy of NAC. And we examined the relation between the expression of plakoglobin and E-cadherin, EMT marker.

Results: The patient with high plakoglobin expression had significantly worse OS (p=0.021, log-rank) and DFS (p=0.015, log-rank), DMFS (p=0.040, log-rank). And the plakoglobin expression had no correlation with pathological complete response (pCR) rate (p=0.596). Also, there was not a statistically significant relationship between the plakoglobin expression and other clinicopathological parameters including tumor size (p=0.708), lymph node status (p=0.479), subtype (p=0.413), nuclear grade (p=0.642), Ki67 (p=0.202), tumor infiltrating lymphocytes (p=0.828). On univariate analysis with respect to distal metastasis, high plakoglobin expression showed worse prognosis than low plakoglobin expression (p=0.013, hazard ratio=4.221). And multivariate analysis found the same result (p=0.015, hazard ratio=4.070). In addition, there was a significant relationship between the expression of plakoglobin and E-cadherin (p=0.023).

Conclusions: Plakoglobin expression is an independent prognostic factor in the patients with breast cancer; particularly for DMFS, and this mechanism related to EMT.Background: Accumulating evidence shows that circulating tumor cells (CTC) are linked to metastatic relapse and are regarded as a prognostic marker for human cancer. It was reported that CTC clusters (CTCc) have more metastatic potential than single CTC. Lately, studies also show that the high expression of plakoglobin, a cell adhesion protein, within the primary tumor are positively associated with CTCc in breast cancer patients. In addition, it is thought that insufficient expression of plakoglobin could promote epithelial-mesenchymal transition (EMT). In this study, we investigated the correlation between plakoglobin expression and survival of breast cancer.

Materials and Methods:A total of 126 patients with resectable early-stage breast cancer were treated with neoadjuvant chemotherapy (NAC). All patients received a standardized protocol of NAC consisting of four courses of FEC100 (500 mg/m2 fluorouracil, 100 mg/m2 epirubicin, and 500 mg/m2 cyclophosphamide) every 3 weeks, followed by 12 courses of 80 mg/m2 paclitaxel administered weekly. The expression of plakoglobin were identified by immunohistochemical staining properties in cell membrane. Staining with plakoglobin (clone 4C12) was scored according to the percentage of cells that stained positively: low, 0-25%; medium, 26-75%; high, >75%. We investigated the correlation between the plakoglobin expression in primary tumor specimen and clinical outcomes including overall-survival (OS), disease-free-survival (DFS), distant-metastasis-free-survival (DMFS), the efficacy of NAC. And we examined the relation between the expression of plakoglobin and E-cadherin, EMT marker.

Results: The patient with high plakoglobin expression had significantly worse OS (p=0.021, log-rank) and DFS (p=0.015, log-rank), DMFS (p=0.040, log-rank). And the plakoglobin expression had no correlation with pathological complete response (pCR) rate (p=0.596). Also, there was not a statistically significant relationship between the plakoglobin expression and other clinicopathological parameters including tumor size (p=0.708), lymph node status (p=0.479), subtype (p=0.413), nuclear grade (p=0.642), Ki67 (p=0.202), tumor infiltrating lymphocytes (p=0.828). On univariate analysis with respect to distal metastasis, high plakoglobin expression showed worse prognosis than low plakoglobin expression (p=0.013, hazard ratio=4.221). And multivariate analysis found the same result (p=0.015, hazard ratio=4.070). In addition, there was a significant relationship between the expression of plakoglobin and E-cadherin (p=0.023).

Conclusions: Plakoglobin expression is an independent prognostic factor in the patients with breast cancer; particularly for DMFS, and this mechanism related to EMT.

Citation Format: Goto W, Kashiwagi S, Asano Y, Takada K, Takashima T, Morisaki T, Noda S, Onoda N, Ohsawa M, Hirakawa K, Ohira M. Circulating tumor cell clusters-associated gene plakoglobin is a novel prognostic predictor in patients with breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-25.

Abstract P3-04-20: Predicting therapeutic effect by on tumor invasion lymphocytes (TILs) in endocrine therapy for stage IV breast cancer

Background: Breast cancer with distant metastasis at first presentation (stage IV disease) is often encountered in the outpatient department. With recent advances in multimodal therapies for breast cancer, long-term survival can now be expected even in stage IV breast cancer with distant metastasis. However, a goal in treating metastatic disease is prolongation of survival while maintaining good quality of life (QOL). Endocrine therapy is suitable for this purpose.The tumor immune environment not only modulates the effects of immunotherapy, but also the effects of other anticancer drugs and treatment outcomes. These immune responses can be evaluated with tumor-infiltrating lymphocytes (TILs), which has frequently been verified clinically. In the present study, we hypothesized that TILs would be useful as predictive marker of the therapeutic effect in endocrine therapy as well. In this study, the prediction of the therapeutic effect by TILs in endocrine therapy for stage IV breast cancer was clinically verified.

Materials and Methods:Data from 40 patients who underwent endocrine therapy as the initial drug therapy for stage IV breast cancer were used. The correlation between TILs evaluated according to the standard method, and prognosis, including the efficacy of endocrine therapy, was investigated retrospectively. Patients with 350% lymphocytic infiltration were considered to have lymphocyte-predominant breast cancer (LPBC).

Results:Among all 40 patients, TIL levels were high in 13 (32.5%) and low in 27 (67.5%) patients. Nine patients (22.5%) had LPBC, and 31 patients (77.5%) had non-LPBC. Investigation of the clinical pathological features of patients showed no significant differences between the high TIL and low TIL groups. There were also no significant differences between LPBC and non-LPBC patients. An analysis of outcomes comparing the high TIL and low TIL groups showed no prolongation in progression-free survival (PFS) (p=0.171, log-rank), time to treatment failure (TTF)(p=0.054), or overall survival (OS) (p=0.641). LPBC patients had significant prolongations of PFS (p=0.005), TTF (p=0.001), and OS (p=0.027) compared to non-LPBC patients. On receiver operating characteristic (ROC) curve analyses, results were better with LPBC (AUC: 0.700) than with TILs (AUC: 0.606).

Conclusion: The present findings suggest that a high level of lymphocytic infiltration in the tumor stroma may serve as a predictor of the therapeutic effect of endocrine therapy for patients with stage IV ER-positive breast cancer.

Citation Format: Kashiwagi S, Asano Y, Goto W, Takada K, Takashima T, Morisaki T, Noda S, Onoda N, Ohsawa M, Hirakawa K, Ohira M. Predicting therapeutic effect by on tumor invasion lymphocytes (TILs) in endocrine therapy for stage IV breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-04-20.

Abstract P2-05-05: Prediction of survival after neoadjuvant chemotherapy for breast cancer by evaluation of tumor-infiltrating lymphocytes (TILs) and residual cancer burden (RCB)

Background: The tumor immune environment not only modulates the effects of immunotherapy, but also the effects of other anticancer drugs and treatment outcomes. Thus, the importance of inhibiting and improving the tumor immune microenvironment is now recognized. These immune responses can be evaluated with tumor-infiltrating lymphocytes (TILs), which has frequently been verified clinically. On the other hand, residual cancer burden (RCB) evaluation has been shown to be a useful predictor of survival after neoadjuvant chemotherapy (NAC). In this study, RCB and TILs evaluations were combined to produce an indicator that we have termed “RCB-TILs”, and its clinical application to NAC for breast cancer was verified by subtype-stratified analysis.

Materials and Methods:A total of 177 patients with resectable early-stage breast cancer were treated with NAC.The correlation between TILs evaluated according to the standard method, and prognosis, including the efficacy of NAC, was investigated retrospectively. The RCB was calculated using the Residual Cancer Burden Calculator on the website of the MD Anderson Cancer Center. The RCB and TILs evaluations were combined to create the “RCB-TILs”. Patients who were RCB-positive and had high TILs were considered RCB-TILs-positive, and all other combinations were RCB-TILs-negative.

Results: Univariable analysis of patients with high TILs found that this contributed significantly to prolonging DFS in all patients (p = 0.022, hazard ratio = 0.420), TNBC patients (p = 0.004, hazard ratio = 0.177), and HER2BC patients (p = 0.026, hazard ratio = 0.123). For HRBC patients, however, high TILs did not contribute to survival (p = 0.990, hazard ratio = 0.992). Being RCB-TILs-positive, however, contributed significantly to prolonging DFS in all patients (p < 0.001, hazard ratio = 0.181), TNBC patients (p < 0.001, hazard ratio = 0.099), HER2BC patients (p = 0.026, hazard ratio = 0.123), and HRBC patients (p = 0.039, hazard ratio = 0.258). On multivariable analysis, being RCB-TILs-positive was an independent factor for recurrence after NAC in all patients (p < 0.001, hazard ratio = 0.048), TNBC patients (p = 0.018, hazard ratio = 0.041), HER2BC patients (p = 0.036, hazard ratio = 0.134), and HRBC patients (p = 0.002, hazard ratio = 0.081).

Conclusion: The results of the present study suggest that RCB-TILs is a significant predictor for breast cancer recurrence after NAC and may be a more sensitive indicator than TILs alone.

Citation Format: Asano Y, Kashiwagi S, Goto W, Takada K, Takashima T, Morisaki T, Noda S, Onoda N, Ohsawa M, Hirakawa K, Ohira M. Prediction of survival after neoadjuvant chemotherapy for breast cancer by evaluation of tumor-infiltrating lymphocytes (TILs) and residual cancer burden (RCB) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-05-05.

Tumour-infiltrating CD8 to FOXP3 lymphocyte ratio in predicting treatment responses to neoadjuvant chemotherapy of aggressive breast cancer

BACKGROUND

Tumour-infiltrating lymphocytes (TILs) can be used to monitor the immune response, and are important in predicting treatment responses and outcomes for various types of cancer. Recently, specific TIL subsets have been reported to be clinically useful in predicting treatment responses. The CD8+/FOXP3+ TIL ratio (CFR) may be a more sensitive indicator for monitoring immune function. This study investigated the clinical significance and value of CFR as a biomarker to predict treatment responses to neoadjuvant chemotherapy for breast cancer.

METHODS

Patients with resectable early-stage breast cancer treated with neoadjuvant chemotherapy at Osaka City University Hospital, Japan, between 2007 and 2013 were included. Oestrogen receptor, progesterone receptor, human epidermal growth factor receptor (HER) 2, Ki-67, CD8 and FOXP3 status were assessed by immunohistochemistry, and correlated with pathological complete response (pCR).

RESULTS

A total of 177 patients were included, of whom 90 had a high CFR and 87 a low CFR. Triple-negative breast cancer (TNBC) was more common in the high-CFR group than in the low-CFR group (46 versus 23 per cent; P = 0·002), as was HER2-enriched breast cancer (HER2BC) (27 versus 14 per cent; P = 0·033). Among these patients, the pCR rate was significantly higher in the high-CFR group than in the low-CFR group (TNBC: P = 0·022; HER2BC: P < 0·001). In multivariable analysis high-CFR status was an independent predictor of a favourable prognosis: hazard ratio 0·24 (95 per cent c.i. 0·05 to 0·72; P = 0·015) for TNBC and 0·10 (0·10 to 0·90; P = 0·041) for HER2BC.

CONCLUSION

The CFR may be a useful biomarker to predict treatment response to neoadjuvant therapy in aggressive breast cancer subtypes, such as TNBC and HER2BC.

Olanzapine increases hepatic glucose production through the activation of hypothalamic adenosine 5'-monophosphate-activated protein kinase

AIMS

To investigate the mechanism of the metabolic disturbance induced by the atypical antipsychotic olanzapine, we examined whether adenosine 5'-monophosphate-activated protein kinase (AMPK) in the hypothalamus and hepatic glucose production are involved in the effect of olanzapine.

METHODS

Male 6-week-old ICR mice were used. Blood glucose levels were determined by the glucose oxidase method. The mRNA levels of gluconeogenic or glycolytic enzymes were measured by reverse transcription polymerase chain reaction (RT-PCR). AMPK expression was measured by Western blotting.

RESULTS

Systemic injection of olanzapine increased blood glucose levels in both unfasted and fasted mice. However, the increase in fasted mice was less than that in unfasted mice. Central administration of olanzapine also increased the blood glucose levels in unfasted mice, but not in fasted mice. In a pyruvate tolerance test, olanzapine significantly increased blood glucose levels. In addition, olanzapine increased the mRNA levels of glucose-6-phosphatase (G6Pase), a gluconeogenic enzyme, in the liver. Furthermore, olanzapine increased phosphorylated AMPK in the hypothalamus of unfasted mice, and olanzapine-induced hyperglycaemia was inhibited by the AMPK inhibitor compound C. Central administration of the AMPK activator AICAR significantly increased G6Pase mRNA levels in the liver and blood glucose levels. Moreover, both olanzapine- and AICAR-induced hyperglycaemia were attenuated by the β-adrenergic receptor antagonist propranolol, suggesting that olanzapine and AICAR induce hepatic glucose production through the sympathetic nervous system.

CONCLUSIONS

Our results indicate that olanzapine activates AMPK in the hypothalamus, which increases hepatic glucose production via the sympathetic nervous system.

[Proposal for an auxiliary tool designed to reduce retake rates for lateral radiography of the knee joint]

The reproducibility of lateral radiography of the knee joint in the lateral position is low because patient positioning can be easily affected by passive rotation of the knee joint. We calculated the correction angle of the femoral external rotation and the lower leg elevation and developed our own auxiliary tool for obtaining a lateral view image. We were able to obtain, in a single attempt, an image with misalignment of the condyle limited to less than 7 mm. Our tool also contributed to the reduction of the re-imaging rate, suggesting its usefulness in contributing to a lower re-imaging rate for lateral radiography of the knee joint.

Activation of spinal cannabinoid CB2 receptors inhibits neuropathic pain in streptozotocin-induced diabetic mice

The role of spinal cannabinoid systems in neuropathic pain of streptozotocin (STZ)-induced diabetic mice was studied. In normal mice, injection of the cannabinoid receptor agonist WIN-55,212-2 (1 and 3μg, i.t.) dose-dependently prolonged the tail-flick latency, whereas there were no changes with the injection of either cannabinoid CB1 (AM 251, 1 μg, i.t.) or CB2 (AM 630, 4 μg, i.t.) receptor antagonists. AM 251 (1 μg, i.t.), but not AM 630 (4 μg, i.t.), significantly inhibited the prolongation of the tail-flick latency induced by WIN-55,212-2 (3 μg, i.t.). In STZ-induced diabetic mice, the tail-flick latency was significantly shorter than that in normal mice. A low dose of WIN-55,212-2 (1 μg, i.t.) significantly recovered the tail-flick latency in STZ-induced diabetic mice. The effect of WIN-55,212-2 (1 μg, i.t.) in STZ-induced diabetic mice was significantly inhibited by AM 630 (4 μg, i.t.), but not AM 251 (1 μg). The selective cannabinoid CB2 receptor agonist L-759,656 (19 and 38 μg, i.t.) also dose-dependently recovered the tail-flick latency in STZ-induced diabetic mice, and this recovery was inhibited by AM 630 (4 μg, i.t.). The protein levels of cannabinoid CB1 receptors, CB2 receptors and diacylglycerol lipase α (DGL-α), the enzyme that synthesizes endocannabinoid 2-arachidonoylglycerol, in the spinal cord were examined using Western blotting. The protein levels of both cannabinoid CB1 and CB2 receptors were increased in STZ-induced diabetic mice, whereas the protein level of DGL-α was significantly decreased. These results indicate that spinal cannabinoid systems are changed in diabetic mice and suggest that cannabinoid CB2 receptor agonists might have an ability to recover diabetic neuropathic pain.

Risk factors affecting cardiac left-ventricular hypertrophy and systolic and diastolic function in the chronic phase of allogeneic hematopoietic cell transplantation

Chronic impairment of cardiac function can be an important health risk and impair the quality of life, and may even be life-threatening for long-term survivors of allogeneic hematopoietic cell transplantation (HCT). However, risk factors for and/or the underlying mechanism of cardiac dysfunction in the chronic phase of HCT are still not fully understood. We retrospectively investigated factors affecting cardiac function and left-ventricular hypertrophy (LVH) in the chronic phase of HCT. Sixty-three recipients who survived for >1 year after receiving HCT were evaluated using echocardiography. Based on simple linear regression models, high-dose TBI-based conditioning was significantly associated with a decrease in left-ventricular ejection fraction and the early peak flow velocity/atrial peak flow velocity ratio, following HCT (coefficient=-5.550, P=0.02 and coefficient=-0.268, P=0.02, respectively). These associations remained significant with the use of multiple linear regression models. Additionally, the serum ferritin (s-ferritin) level before HCT was found to be a significant risk factor for LVH on multivariable logistic analysis (P=0.03). In conclusion, our study demonstrated that a myeloablative regimen, especially one that involved high-dose TBI, impaired cardiac function, and that a high s-ferritin level might be associated with the development of LVH in the chronic phase of HCT.

Fatal BK virus pneumonia following stem cell transplantation

We report the case of a 39-year-old male patient who died of severe BK virus (BKV) pneumonia 168 days after hematopoietic stem cell transplantation (HSCT) for acute lymphoblastic leukemia. After suffering from BKV-associated late-onset hemorrhagic cystitis (HC) with long-term sustained BKV viremia, he died of rapidly progressive pneumonia. On autopsy, numerous viral intranuclear inclusions were seen in his lungs and bladder. An immunohistochemical examination of his lungs was positive for simian virus 40. Based on these pathological results and the high sustained BKV viral load in his blood, we reached a diagnosis of BKV pneumonia. Viral infection can occasionally become life threatening among HSCT recipients. It is widely known that BKV can cause late-onset HC, but BKV-associated pneumonia is rare. Because of its rapid progression and poor prognosis, it is difficult to make an antemortem diagnosis of BKV pneumonia. A treatment strategy for BKV pneumonia also needs to be formulated. Similar to other viral pathogens, BKV can cause pneumonia and the clinician should therefore be aware of it in immunocompromised patients.

Spontaneously complete regression of pseudolymphoma of the remnant pancreas after pancreaticoduodenectomy

BACKGROUND

Pancreatic pseudolymphoma is extremely rare.

METHOD

We present multiple pseudolymphomas in the head and body of the pancreas. The hypoechoic lesions observed by endoscopic ultrasound were enhanced in late-phase angio-computed tomography and homogeneously hypointensive in T1-weighted magnetic resonance imaging (MRI). (18)F-fluorodeoxyglucose positron emission tomography showed strong accumulation in the lesions. The lesions were suspected to be non-functioning islet cell carcinoma. The intraoperative pathological diagnosis for the specimen obtained by a pylorus-preserving pancreaticoduodenectomy was non-neoplastic lymphoid cells. The remnant lesion in the pancreatic body was preserved.

RESULTS

Macroscopically, the mass was well-circumscribed gray-white colored lesion. The pathological diagnosis was pancreatic pseudolymphoma. The lesion in the remnant pancreas spontaneously disappeared within one year after the operation.

CONCLUSION

The differential diagnosis of pancreatic pseudolymphoma from malignant tumor is very difficult, however, the image findings demonstrated here may be informative. The spontaneous disappearance of pancreatic pseudolymphoma was firstly observed in the present case.

Prehypertension subtype with elevated C-reactive protein: risk of ischemic stroke in a general Japanese population

BACKGROUND

Prehypertension (PreHT) and low-grade inflammation are both known to be related to the incidence of cardiovascular events. This cohort study investigated whether the high-risk group for future ischemic stroke among PreHT subjects can be predicted by stratification of high-sensitivity C-reactive protein (hsCRP).

METHODS

A total of 22,676 subjects aged 40-80 years from the general population who had no cardiovascular history underwent baseline measurement of serum hsCRP, and were followed for the incidence of ischemic stroke.

RESULTS

During the mean follow-up period of 2.7 years, 143 subjects had a first ischemic stroke. In a Cox multivariable model after adjustment for cardiovascular risk factors, there was no significant difference in hazard ratio (HR) for incidence of ischemic stroke between the normotension (NT) and PreHT subjects (HR = 1.72, 95% confidence interval (CI): 0.93-3.18, vs. NT subjects). In contrast, the HR for incidence of ischemic stroke in PreHT subjects with higher hsCRP levels (≥0.5 mg/l in men, ≥0.4 mg/l in women, more than median levels according to sex) was increased compared to NT subjects with lower hsCRP levels (HR = 2.63, 95% CI: 1.11-6.24). Moreover, the HR for incidence of ischemic stroke in PreHT subjects with lower CRP levels (HR = 0.91, 95% CI: 0.31-2.73) did not differ from that in NT subjects with lower hsCRP levels.

CONCLUSIONS

This study showed that, in a Japanese general population, hsCRP was a marker for relatively short-term risk of ischemic stroke in PreHT subjects.

[Survey on scanning pediatric patients' heads with CT]

Pediatric patients are especially sensitive to radiation, and when scanning their heads with CT, it is necessary to do so with a low dose and pay very close attention. However, there are many problems when scanning pediatric patients, and it is often confusing to set the conditions for scanning. To do a survey and comparison, we issued a questionnaire to 23 pediatric hospitals and 89 university hospitals, asking about their usage of sedation, studied disorders, as well as how and under what conditions they scan their patients. The percentage of response was 40% in total. Based on the questionnaire results, we could not see much difference in the conditions for scanning. However, there was a significant difference in the usage of sedation and studied disorders between pediatric hospitals and university hospitals. The most studied disorders at pediatric hospitals were convulsion and consciousness disorders, and low-contrast areas such as the albocinereous, which requires images without movement artifacts. In order to obtain clear images, the patient was put under sedation. On the other hand, university hospitals often deal with external injuries, which usually involve danger in using sedation, and patients are usually examined without it. In addition, the usage of sedation is rare because bleeding brings up high-contrast images, and it is easy to make a diagnosis even if there is some movement artifact. Also to aim at setting a standard for medical technology, from here on, guidelines of examining methods and setting conditions should be made depending on how the different disorders should be treated.

Neopterin is associated with plaque inflammation and destabilisation in human coronary atherosclerotic lesions

BACKGROUND

Previous studies have shown that recent activation of the inflammatory response in coronary atherosclerotic lesions contributes to rapid progressive plaque destabilisation. Neopterin, a by-product of the guanosine triphosphate pathway, is produced by activated macrophages and serves as an activation marker for monocytes/macrophages.

OBJECTIVE

To elucidate the role of neopterin in coronary plaque destabilisation by immunohistochemical study of the presence of neopterin in coronary atherectomy specimens obtained from patients with stable angina pectoris (SAP) and unstable angina pectoris (UAP).

PATIENTS AND METHODS

All patients underwent atherectomy of the primary atherosclerotic lesions responsible for SAP (n = 25) and UAP (n = 25). Frozen samples were studied with antibodies against smooth muscle cells, macrophages, T cells, neutrophils and neopterin.

RESULTS

In 22/25 patients with UAP, abundant neopterin-positive macrophages were found at the sites of coronary culprit lesions. However, in 25 lesions from patients with SAP, only 11 lesions showed neopterin positivity. Quantitatively, the neopterin-positive macrophage score was significantly higher (p<0.001) in patients with UAP than in patients with SAP. Moreover, the neopterin-positive macrophage score showed a significant positive correlation with the number of neutrophils or T cells, respectively (neutrophils, r = 0.55, p<0.001; T cells, r = 0.70, p<0.001).

CONCLUSIONS

Neopterin can be considered as one of the significant factors in the process of plaque inflammation and destabilisation in human coronary atherosclerotic lesions. Its exact role in the process needs to be investigated further.

Mast cells in diffuse large B-cell lymphoma; their role in fibrosis

AIMS

Mast cells (MCs) are associated with fibrosis in various diseases. MCs comprise two phenotypes: the MC(TC) phenotype contains tryptase and chymase, whereas the MC(T) phenotype contains tryptase. Interleukin (IL)-4 promotes the development of MC(TC) from the MC(T) phenotype. The aim of this study was to determine the relationship between MC phenotypes and fibrosis in diffuse large B-cell lymphoma (DLBCL).

METHODS AND RESULTS

We examined the distribution and density of MCs in 50 DLBCL and 20 reactive lymph nodes, and evaluated MC phenotypes and IL-4-expressing cells. To detect MCs, immunohistochemistry for tryptase and chymase was performed. The 50 DLBCLs were histologically divided into three groups: no fibrosis (32 cases), reticular type (eight cases) showing reticular fibrosis, and bundle type (10 cases) showing collagenous bundles. The density of tryptase-positive MCs was higher than that of chymase-positive MCs. The densities of tryptase-positive and chymase-positive MCs in fibrotic areas were significantly higher than those in the cellular areas in the reticular and bundle groups. Double immunostaining revealed that MCs in DLBCL comprised MC(T) and MC(TC) phenotypes. Chymase-positive MCs and T lymphocytes expressed IL-4. Although there were few chymase-positive MCs in reactive lymph nodes, the density of tryptase-positive MCs was not different from that in the 'no fibrosis' group.

CONCLUSIONS

Tryptase-positive and chymase-positive MCs are associated with fibrosis in DLBCL.

[Valve-in-valve replacement of primary tissue valve failure of bovine pericardial valve minor]

A 73-year-old woman who underwent mitral valve replacement with a 31 mm Carpentier Edwards Pericardial Xenograft 19 years ago. She revealed sudden onset of a grade IV/VI a seagull like diastolic murmur at the apex, and severe hematuria. Echocardiography demonstrated severe mitral regurgitation. These findings were consistent with acute primary tissue valve failure. Therefore we performed emergency reoperation. At operation, valve leaflet was torn at the commissural stitch, and bioprosthesis strut was buried in the left posterior ventricular wall. The mitral prosthetic valve replaced with a 25 mm CarboMedics OptiForm using a technique of valve-in-valve replacement. This procedure would be one option for replacement of bioprosthetic mitral valve.

Oxidized Phosphatidylcholine in AlveolarMacrophages in Idiopathic Interstitial Pneumonias

It has been suggested that oxidative stress plays a pathogenic role in idiopathic interstitial pneumonias. Macrophage- or neutrophil-derived oxidants seem to be important sources of oxidative stress in this group of inflammatory disorders. Recent experimental studies have revealed that oxidative injury during inflammation or apoptosis can change phosphatidylcholine of cell membrane into its oxidized form, which serves as a ligand for macrophage scavenger receptor CD36. Recently, we developed a monoclonal antibody against oxidized phosphatidylcholine. Using this novel antibody, we performed an immunohistochemical investigation to clarify the localization of oxidized phosphatidylcholine in lung tissues of idiopathic interstitial pneumonias and a relationship between oxidized phosphatidylcholine localization and CD36 expression. Lung specimens obtained from patients with desquamative (n = 8) or usual interstitial pneumonia (n = 15) were studied. Thirteen normal lung tissues were also examined as controls. Antibodies against oxidized phosphatidylcholine, CD36, epithelial cells, macrophages, and neutrophils were used as primary antibodies. The positive cell number was counted by computer-aided morphometry. While there were no oxidized phosphatidylcholine-positive cells in normal lungs, lungs of desquamative or usual interstitial pneumonia contained large numbers of oxidized phosphatidylcholine-positive cells in the alveolar spaces. Double-staining analysis revealed that most oxidized phosphatidylcholine-positive cells were macrophages. The oxidized phosphatidylcholine-positive cells were increased in association with the increase in the densities of macrophages (Rs = 0.87, p < 0.0001) and neutrophils (Rs = 0.89, p < 0.0001). Accumulated macrophages also showed distinct CD36 expression. These findings suggest that oxidative stress and the related product, oxidized phosphatidylcholine, play an important role in the pathophysiology of idiopathic interstitial pneumonias.

Identification and prevalence of an enterotoxin-related gene, se-int, in Staphylococcus intermedius isolates from dogs and pigeons

AIMS

To determine the prevalence of enterotoxin-producing Staphylococcus intermedius in dogs and pigeons.

METHODS AND RESULTS

A total of 106 S. intermedius isolates from 44 dogs and 62 pigeons were tested for the production of enterotoxins A, B, C and D by reverse passive latex agglutination (RPLA) and for sec-canine by PCR. Only one isolate from dog was positive for SEC and sec-canine. Screening of sec-canine-negative strains by nested PCR led to the identification of a novel enterotoxin-related gene, se-int. SE-int showed a significant homology (59-61% identity) with SEC and (56.6% identity) SEB. All 44 isolates from dogs and five isolates (8.1%) from pigeons were se-int positive.

CONCLUSIONS

While S. intermedius was isolated more frequently from pigeons than from dogs, se-int was more prevalent among the S. intermedius isolates from dogs, compared with the pigeon isolates.

SIGNIFICANCE AND IMPACT OF THE STUDY

Further characterization of the se-int-positive S. intermedius strains should clarify their pathogenic potential including enterotoxigenicity and zoonotic transmissibility to human beings.

Hepatitis C virus genotype testing in paraffin wax embedded liver biopsies for specimen identification

Despite advances in medical technology, careful specimen identification is still a fundamental principle of laboratory testing. If pathological samples are mixed up, especially in the case of extremely small biopsy samples, large amounts of time and energy may be wasted in correctly identifying the specimens. Recently, two liver biopsy specimens were mixed up in this department, and a new pathological technology was used to resolve the issue. Liver biopsy was performed on two patients with hepatitis C virus (HCV) infection. During sample transfer or tissue processing, the biopsy specimens were mixed up. Because the ABO blood group of the two patients was identical (type AB), the specimens were subsequently identified by analysing the HCV genotypes. RNA extracted from the paraffin wax embedded liver specimens was examined by a polymerase chain reaction based HCV genotype assay. This enabled the correct identification of the specimens, and each patient received the appropriate treatment on the basis of the accurate diagnosis.

Mast cell chymase expression inHelicobacter pylori-associated gastritis

AIMS

To study the role of mast cell chymase in the inflammatory processes of human chronic gastritis. Experimental studies have shown that mast cell chymase stimulates inflammatory cell accumulation, and contributes to angiotensin II formation.

METHODS AND RESULTS

Tissue sections from human stomachs with Helicobacter pylori-associated gastritis (surgery/autopsy n = 20; biopsy n = 16) and normal stomachs (n = 10) were studied using immunohistochemical single and double labelling techniques. Monoclonal antibodies used were directed against mast cell chymase, tryptase, neutrophils (CD66b, elastase, and myeloperoxidase), macrophages, T-lymphocytes, and interleukin (IL)-4. The expression of angiotensin-converting enzyme and angiotensin II type 1 receptor was investigated using immunohistochemical analysis and the reverse transcription-polymerase chain reaction. The number of chymase-positive mast cells was significantly higher (P < 0.0001) in H. pylori-associated gastritis than in normal stomachs. Increased expression of chymase in inflamed mucosa was closely related to an increase in the accumulation of neutrophils, macrophages, T-lymphocytes, and IL-4-positive cells. The expression of angiotensin-converting enzyme and angiotensin II type 1 receptor was not altered in gastritis specimens.

CONCLUSIONS

These observations suggest that mast cell chymase may be an important mediator in the inflammatory processes of human H. pylori-associated gastritis.

Release of [Met5]enkephalin from the spinal cord by intraventricularly administered endomorphin-2, but not endomorphin-1 in the anesthetized rat

Effects of intraventricular injection of endomorphin-1, endomorphin-2 and beta-endorphin on the release of immunoreactive [Met(5)]enkephalin from the spinal cord were studied in pentobarbital anesthetized rats. Intraventricular injection of endomorphin-2, but not endomorphin-1, caused an increased release of immunoreactive [Met(5)]enkephalin in the spinal perfusates. Beta-endorphin given intraventricularly also increased the release of immunoreactive [Met(5)]enkephalin in an amount 15-fold higher than that produced by endomorphin-2. The increase of the release of immunoreactive [Met(5)]enkephalin induced by endomorphin-2 was blocked by mu-opioid receptor antagonist CTOP. Our result suggests that endomorphin-2 stimulates another subtype of mu-opioid receptor different from that acted by endomorphin-1 at the supraspinal site and subsequently increases the release of [Met(5)]enkephalin from the spinal cord.

Reduced hyperalgesia induced by nerve injury, but not by inflammation in mice lacking protein kinase C gamma isoform

Protein kinase C is one of protein kinases which might be involved in the nerve injury- or inflammation-induced hyperalgesia. The present study was designed to investigate the hyperalgesia with thermal paw-withdrawal test induced by sciatic nerve ligation or by intraplantar injection of a complete Freund's adjuvant solution in protein kinase C gamma knockout and its wild-type mice. Either sciatic nerve ligation or intraplantar injection of a complete Freund's adjuvant caused a marked decrease of the paw-withdrawal latency only on the ipsilateral, but not on the contralateral side of the paw in wild-type mice. This ipsilateral hyperalgesia induced by sciatic nerve ligation was significantly attenuated in protein kinase C gamma knockout mice. On the other hand, the ipsilateral hyperalgesia induced by complete Freund's adjuvant remained about the same in protein kinase C gamma knockout mice as in wild-type mice. The results indicate that protein kinase C gamma is involved in the development of the thermal hyperalgesia induced by nerve ligation, but not by complete Freund's adjuvant-induced inflammation.

Accumulation of beta-catenin in the cytoplasm and the nuclei during the early hepatic tumorigenesis

Hepatocellular carcinomas (HCCs) are thought to develop as well-differentiated tumors and progress to less-differentiated tumors. However, the genetic changes underlying the development and progression of HCCs are not well understood. Recent studies have shown frequent beta-catenin gene activation in HCCs by somatic alterations involving exon 3, resulting in the activation of the Wnt/Wingless signal transduction pathway. However, the exact process in which activation of Wnt/Wingless signal transduction pathway occurs during hepatic tumorigenesis remains to be elucidated. The aim of the present study was to investigate at what stage of hepatocellular tumorigenesis this pathway was activated. Altered expression of beta-catenin was investigated immunohistochemically with special reference to the grade of histological differentiation in 41 HCCs and eight dysplastic nodules. Mutational analysis of the beta-catenin gene with single-strand conformation polymorphism method and polymerase chain reaction amplification was related with the expression of this protein. beta-Catenin was expressed in the cytoplasm and the nuclei in three cases among eight dysplastic nodules, in four cases among 20 well differentiated HCCs, in five cases among 15 moderately differentiated HCCs, and one case among six poorly differentiated HCCs, respectively. Expression of beta-catenin in the cytoplasm and the nuclei was associated in one case with mutation and two cases without mutation for beta-catenin gene among 11 screened HCCs. It was concluded that beta-catenin was accumulated in the cytoplasm and the nuclei in pre-cancerous lesions of the liver and might contribute, at least in part, to hepatic tumorigenesis.

Differential antinociception induced by spinally administered endomorphin-1 and endomorphin-2 in the mouse

We have previously demonstrated that the antinociception induced by either endomorphin-1 or endomorphin-2 given supraspinally is mediated by the stimulation of mu-opioid receptors. However, the antinociception induced by endomorphin-2 given supraspinally contains additional components, which are mediated by the spinal release of dynorphin A (1-17) acting on kappa-opioid receptors and the spinal release of [Met5]enkephalin acting on delta2-opioid receptors in the spinal cord. The present studies were performed to determine whether there are any differential effects on the tail-flick inhibition induced by endomorphin-1 and endomorphin-2 given intrathecally (i.t.) in mice. Endomorphin-1 or endomorphin-2 given i.t. inhibited the tail-flick response in a dose-dependent manner. The tail-flick inhibition induced by endomorphin-1 was blocked by i.t. pretreatment with mu-opioid receptor antagonist D-Phe-Cys-Tyr-D-Try-Orn-Thr-Pen-Thr-NH2 (CTOP), but not kappa-opioid receptor antagonist nor-binaltorphimine (nor-BNI), delta1-opioid receptor antagonist 7-benzylidene naltrexamine (BNTX), or delta2-opioid receptor antagonist naltriben (NTB). In contrast, the tail-flick inhibition induced by endomorphin-2 given i.t. was blocked by i.t. pretreatment with CTOP or nor-BNI, but not BNTX or NTB. Intrathecal pretreatment with antiserum against dynorphin A (1-17), but not antiserum against [Met5]enkephalin, [Leu5]enkephalin, or beta-endorphin, blocked the tail-flick inhibition induced by i.t.-administered endomorphin-2. None of these antisera attenuated the i.t.-administered endomorphin-1-induced tail-flick inhibition. It is concluded that the tail-flick inhibition induced by endomorphin-1 and endomorphin-2 given spinally is mediated by the stimulation of mu-opioid receptors. However, the tail-flick inhibition induced by spinally injected endomorphin-2 contains an additional component, which is mediated by the spinal release of dynorphin A (1-17) acting on kappa-opioid receptors in the spinal cord. We propose that there are at least two different subtypes of micro-opioid receptors for endomorphin-1 and endomorphin-2 to produce antinociception in the spinal cord.

Antisera against endogenous opioids increase the nocifensive response to formalin: demonstration of inhibitory beta-endorphinergic control

The roles of endogenous opioid peptides in the brain in the modulation of nocifensive responses to formalin in ICR mice were studied. Mice were pretreated intracerebroventricularly (i.c.v.) with rabbit antiserum against beta-endorphin, [Leu5]enkephalin, [Met5]enkephalin or dynorphin A-(1-17) 1 h prior to intraplantar injection of formalin (0.5%, 25 microl) and the nocifensive licking responses were then observed. Pretreatment of mice with antiserum against beta-endorphin enhanced the second phase, but not the first phase of the nocifensive responses to formalin. Pretreatment with antiserum against [Leu5]enkephalin also caused a small but statistically significant enhancement of the second phase, but not the first phase of nocifensive responses to formalin. On the other hand, pretreatment with antiserum against [Met5]enkephalin or dynorphin A-(1-17) did not affect the nocifensive response to formalin. Our results indicate that beta-endorphinergic, and to a lesser extent, [Leu5]enkephalinergic systems are activated at the supraspinal sites to attenuate the nocifensive responses to formalin stimulation.

Modification of the effects of benzodiazepines on the exploratory behaviors of mice on a hole-board by diabetes

The effect of diabetes on the emotional behavior of mice was examined using an automatic hole-board apparatus. Changes in the emotional state of mice were evaluated in terms of changes in exploratory activity; i.e., total locomotor activity, numbers and duration of rearing and head-dipping, and latency to the first head-dipping. The number and duration of head-dipping in diabetic mice were less than those in non-diabetic mice. Diazepam (0.1-0.56 mg/kg, i.p.) dose-dependently increased the number and duration of head-dipping at doses that did not produce sedation in both diabetic and non-diabetic mice. In contrast, methyl-beta-carboline-3-carboxylate (1 and 2 mg/kg, i.p.) decreased the number and duration of head-dipping in non-diabetic mice, but not in diabetic mice. The number and duration of head-dipping in diabetic mice were increased by treatment with flumazenil (0.1 and 0.3 mg/kg, i.v.). These doses of flumazenil did not affect the number or duration of head-dipping in non-diabetic mice. The present data indicate that diabetic mice exhibited anxiety in the hole-board test and that a benzodiazepine receptor antagonist affected the attenuated number and duration of head-dipping in diabetic mice. The heightened anxiety in diabetic mice may be due to the dysfunction of the benzodiazepine receptor and/or of central inhibitory systems.

Human chorionic gonadotropin beta-core fragment is directly produced by cancer cells

The present study was undertaken to investigate whether hCG beta-core fragment (hCGbeta cf) was directly produced by cancer cells. Fifteen cell lines, including four choriocarcinoma and five ovarian cancer cell lines, were tested, and immunoreactivity of hCGbeta cf was present in the culture media of five of the cell lines. It was also present in the culture media of Chinese hamster ovary (CHO) cells transfected with hCGbeta gene. In addition to hCGbeta cf, gel chromatography and Western blot analysis of the culture media showed the presence of an hCGbeta cf immunoreactive material with a molecular weight of approximately 40 kDa. In an in vivo study, hCGbeta cf immunoreactivity was detected in the sera of the mice transplanted with NaUCC-3 choriocarcinoma cells, although the ratios of hCGbeta cf/hCG and hCGbeta cf/free hCGbeta were lower than those in the culture medium. Incubation experiments of purified hCGbeta cf in the serum showed no substantial decrease in its values, ruling out the possibility that formation of a macromolecule with serum components may mask hCGbeta cf immunoreactivity in the serum. Taken together, these results indicate that hCGbeta cf immunoreactive materials are directly produced by cancer cells and hCGbeta cf is not a urinary metabolite of hCG or hCGbeta alone. Also, reduced levels of hCGbeta cf in the serum compared with that of intact hCG or free hCGbeta are likely due to its short half-life.

Implications of Ca(2+)-activated Cl(-) channels in the delta-opioid receptor-mediated antinociception in the mouse spinal cord

The present study was designed to investigate the role of Ca(2+)-activated Cl(-) channels in the spinal opioid receptor-mediated antinociception using the mouse tail-flick assay. The antinociception induced by intrathecal (i.t.) administration of a selective delta-opioid receptor agonist [D-Ala(2)]deltorphin II (10 microgram, i.t.) was significantly attenuated by i.t.-pretreatment with selective Ca(2+)-activated Cl(-) channel blockers, IAA-94, flufenamic acid and niflumic acid. By contrast, IAA-94 had no effect on the antinociception induced by i.t.-treated with either the selective mu-opioid receptor agonist [D-Ala(2),N-MePhe(4), Gly-ol(5)]enkephalin or the kappa-opioid receptor agonist U-50,488H. The present results provide evidence for the first time that the Ca(2+)-activated Cl(-) channel is, at least in part, implicated in the delta-, but not the mu- and kappa-opioid receptor-mediated antinociception in the mouse spinal cord.

1alpha,25-dihydroxyvitamin D(3) and its potent synthetic analogs downregulate tissue factor and upregulate thrombomodulin expression in monocytic cells, counteracting the effects of tumor necrosis factor and oxidized LDL

BACKGROUND

We have recently found that a hormonally active form of vitamin D, 1alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)], exerts anticoagulant effects by upregulating the expression of an anticoagulant glycoprotein, thrombomodulin (TM), and downregulating the expression of a critical coagulation factor, tissue factor (TF), in monocytic cells including human peripheral monocytes. In this study, we investigated the counteracting effects of 1,25(OH)(2)D(3) and its potent analogs on TF induction and TM downregulation by tumor necrosis factor and oxidized LDL in monocytic cells and the modulatory effects of potent analogs on TF and TM expression.

METHODS AND RESULTS

Effects of 1,25(OH)(2)D(3) and its potent synthetic analogs (22R)-22-methyl-20-epi-1,25(OH)(2)D(3) (KY3) and 22-oxacalcitriol on TF and TM antigen levels, cell surface activities, and mRNA levels in monocytic cells were examined. 1, 25(OH)(2)D(3) and its potent analogs showed anticoagulant effects in monocytic cells by downregulating TF and upregulating TM expression, counteracting the effects of tumor necrosis factor and oxidized LDL. KY3 was most potent in its regulatory effect on TF and TM expression.

CONCLUSIONS

Because KY3 has the highest affinity for vitamin D receptor, our findings suggest that TF and TM regulation by 1, 25(OH)(2)D(3) analogs is also mediated by vitamin D receptor. The 1, 25(OH)(2)D(3) analogs KY3 and 22-oxacalcitriol may have the potential to serve as an agent for preventing and treating atherosclerotic and other cytokine-mediated thrombotic diseases and as a tool for studying the molecular mechanisms of TF and TM regulation.

Role of the phosphatidylinositol-specific phospholipase C pathway in delta-opioid receptor-mediated antinociception in the mouse spinal cord

Stimulation of delta-opioid receptors has been shown to activate phospholipase C via the activation of G-proteins in vitro. The present study was designed to determine, with the tail-flick method, whether the stimulatory effect of delta-opioid receptor agonists on phospholipase C and inositol lipid turnover participates in the mechanisms of the delta-opioid receptor-mediated antinociception in the mouse spinal cord. Intrathecal pretreatment with the phospholipase C inhibitors neomycin and U73122, which produced no changes in the basal tail-flick latencies when they were injected alone, significantly attenuated the antinociception induced by intrathecal administration of the selective delta-opioid receptor agonist [D-Ala(2)]deltorphin II in mice. The selective phosphatidylinositol-specific phospholipase C inhibitor ET-18-OCH(3) inhibited the antinociception induced by intrathecal administration of [D-Ala(2)]deltorphin II in a dose-dependent manner. In mice undergoing treatment with LiCl, which impairs phosphatidylinositol synthesis, the antinociception induced by intrathecal administration of [D-Ala(2)]deltorphin II was significantly reduced. Co-administration of D-myo-inositol-1,4,5-trisphosphate restored the [D-Ala(2)]deltorphin II-induced antinociception in LiCl-pretreated mice. On the other hand, intrathecal pretreatment with the selective protein kinase C inhibitor calphostin C, but not the protein kinase A inhibitor KT5720, resulted in a dose-dependent enhancement of the [D-Ala(2)]deltorphin II-induced antinociception. These results indicate a potential role for the phospholipase C-inositol-1,4, 5-trisphosphate pathway in the expression of delta-opioid receptor-mediated antinociception in the mouse spinal cord. Furthermore, activation of protein kinase C by the stimulation of delta-opioid receptors may constitute a significant pathway involved in negative modulation of spinal delta-opioid receptor-mediated antinociception.

Activation of the beta-catenin gene by interstitial deletions involving exon 3 as an early event in colorectal tumorigenesis

beta-Catenin has been identified as an oncogene in several tumors including colorectal cancers. beta-Catenin gene is activated by interstitial deletions involving exon 3 in colorectal carcinomas of Japanese population, in contrast to amino acid substitutions detected among Caucasian population. The aim of this study was to examine the type and frequency of beta-catenin gene mutation during early stages of colorectal tumorigenesis. We screened 100 colorectal adenomas for somatic mutations in the beta-catenin gene by single-strand conformation polymorphism method, as well as polymerase chain reaction amplification. In cases with mutations, sequencing analyses and immunohistochemical staining were also performed. Somatic interstitial deletions of 272-413 bp, each of which included all parts of exon 3, were detected in three tumors. However, no adenoma carried missense mutations. We confirmed accumulation of aberrant beta-catenin protein in cytoplasm and nuclei of adenoma cells by immunohistochemical analysis. Our results suggested that activation of the beta-catenin gene by interstitial deletions involving exon 3 might be less frequent compared with frequent alterations of adenomatous polyposis coli (APC) gene, but could be an early event in colorectal tumorigenesis equivalent to APC gene alterations in the Japanese population.

Differential mechanisms mediating descending pain controls for antinociception induced by supraspinally administered endomorphin-1 and endomorphin-2 in the mouse

We have previously demonstrated that both endomorphin-1 and endomorphin-2 produce their antinociception by the stimulation of mu-opioid receptors. However, the antinociception induced by endomorphin-2 contains an additional component, which is mediated by the release of dynorphin A (1-17) acting on kappa-opioid receptors. These studies were done to determine whether the antinociception induced by endomorphin-1 and endomorphin-2 given supraspinally was mediated by the activation of different descending pain control pathways in the mouse. Specific receptor antagonists or antisera against endogenous opioid peptides were injected intrathecally to block the receptors or bind the released endogenous opioid peptides, and endomorphin-1 or endomorphin-2 was then administered i.c.v. to activate the descending pain control systems to produce antinociception. The tail-flick response was used as antinociceptive test. The blockade of the alpha(2)-adrenoceptors and 5-hydroxytryptamine receptors in the spinal cord by i.t. injection of yohimbine and methysergide, respectively, inhibited the antinociception induced by i.c.v.-administered endomorphin-1 and endomorphin-2. However, the antinociception induced by endomorphin-2 was inhibited by i.t. pretreatment with delta(2)-opioid receptor antagonist naltriben or kappa-opioid receptor antagonist nor-binaltorphimine, but not by the mu-opioid receptor antagonist D-Phe-Cys-Tyr-D-Try-Orn-Thr-Pen-Thr-NH(2) or the delta(1)-opioid receptor antagonist 7-benzylidene naltrexamine. Intrathecal pretreatment with antiserum against Met-enkephalin attenuated the antinociception induced by i.c.v.-administered endomorphin-2, but not endomorphin-1. Furthermore, i.t. pretreatment with antiserum against dynorphin A (1-17) also inhibited the antinociception induced by i.c.v.-administered endomorphin-2, but not endomorphin-1. Intrathecal pretreatment with antiserum against Leu-enkephalin or beta-endorphin did not inhibit i.c.v.-administered endomorphin-1- or endomorphin-2-induced antinociception. The results indicate that, like other opioid micro-receptor agonists, morphine, and [D-Ala(2), N-Me-Phe(4), Gly(5)-ol]-enkephalin, endomorphin-1 and endomorphin-2 given i.c.v. produce antinociception by activating spinipetal noradrenergic and serotonergic pathways for producing antinociception. However, the antinociception induced by endomorphin-2 given i.c.v. also contains other components, which are mediated by the release of Met-enkephalin and dynorphin A (1-17) acting on opioid delta(2)- and kappa-receptors, respectively, in the spinal cord.

Involvement of spinal protein kinase C in thermal hyperalgesia evoked by partial sciatic nerve ligation, but not by inflammation in the mouse

Activation of several protein kinases contributes to the development of hyperalgesia evoked by injuries. The present study was designed to investigate the role of protein kinase C in the spinal cord in thermal hyperalgesia evoked by sciatic nerve ligation or by intraplantar injection of complete Freund's adjuvant. The paw withdrawal latency on the ipsilateral side, but not on the contralateral side, was markedly decreased after sciatic nerve ligation. Intraplantar injection of complete Freund's adjuvant also caused markedly decreases of the paw withdrawal latency. Intrathecal pretreatment with protein kinase C inhibitor calphostin C (100 and 250 ng) attenuated the decrease of the paw withdrawal latency evoked by sciatic nerve ligation. In contrast, the decrease of the paw withdrawal latency evoked by inflammation was only slightly attenuated by intrathecal pretreatment with calphostin C. The results indicate that protein kinase C in the spinal cord is involved in the development of the thermal hyperalgesia evoked by nerve ligation and is much less involved in the thermal hyperalgesia by complete Freund's adjuvant's-induced inflammation.

Decreased opioid-induced antinociception but unaltered G-protein activation in the genetic-diabetic NOD mouse

Previous evaluation of antinociceptive action in experimental diabetes has been conducted almost exclusively in chemically induced diabetes mellitus. The purpose of the present study was to evaluate antinociceptive response and G-protein activation by mu-opioid receptor and delta-opioid receptor agonists in the genetic non-obese diabetic (NOD) mouse, a model of type I insulin-dependent diabetes mellitus (IDDM). Tail-flick latency before and after hyperglycemia was unaltered. Hyperglycemic NOD mice were hyporesponsive to intracerebroventricular (i.c.v.) injections of [D-Ala(2)]deltorphin II but not to [D-Ala(2), N-MePhe(4), Gly-ol(5)]enkephalin (DAMGO); however, G-protein activation in pons/medulla assessed by [35S]GTPgammaS binding was not diminished. This suggests that a G-protein defect in signaling cannot account for the hyporesponsiveness of antinociception in this genetic model of IDDM.