Evaluation of the performance of both machine learning models using PET and CT radiomics for predicting recurrence following lung stereotactic body radiation therapy: A single-institutional study

PURPOSE

Predicting recurrence following stereotactic body radiotherapy (SBRT) for non-small cell lung cancer provides important information for the feasibility of the individualized radiotherapy and allows to select the appropriate treatment strategy based on the risk of recurrence. In this study, we evaluated the performance of both machine learning models using positron emission tomography (PET) and computed tomography (CT) radiomic features for predicting recurrence after SBRT.

METHODS

Planning CT and PET images of 82 non-small cell lung cancer patients who performed SBRT at our hospital were used. First, tumors were delineated on each CT and PET of each patient, and 111 unique radiomic features were extracted, respectively. Next, the 10 features were selected using three different feature selection algorithms, respectively. Recurrence prediction models based on the selected features and four different machine learning algorithms were developed, respectively. Finally, we compared the predictive performance of each model for each recurrence pattern using the mean area under the curve (AUC) calculated following the 0.632+ bootstrap method.

RESULTS

The highest performance for local recurrence, regional lymph node metastasis, and distant metastasis were observed in models using Support vector machine with PET features (mean AUC = 0.646), Naive Bayes with PET features (mean AUC = 0.611), and Support vector machine with CT features (mean AUC = 0.645), respectively.

CONCLUSIONS

We comprehensively evaluated the performance of prediction model developed for recurrence following SBRT. The model in this study would provide information to predict the recurrence pattern and assist in making treatment strategies.

Iodine contrast volume reduction in preoperative transcatheter aortic valve implantation computed tomography: Comparison with 64- and 256-multidetector row computed tomography

INTRODUCTION

This study aimed to compare the vascular enhancement and radiation dose in preoperative transcatheter aortic valve implantation (TAVI) computed tomography (CT) with a reduced contrast medium (CM) using volume scans in 256-multidetector row CT (MDCT) with a standard CM using 64-MDCT.

METHODS

This study included 78 patients with preoperative TAVI CT with either 64- or 256-MDCT. The CM was injected at 1.5 mL/kg in the 64-MDCT group and 1.0 mL/kg in the 256-MDCT group. We compared vascular enhancement of the aortic root and access routes, image quality (IQ) scores, and radiation dose in both groups.

RESULTS

Despite the reduced CM (by 33 %) in the 256-MDCT group, the mean vascular enhancement of the right and left subclavian arteries was significantly higher than that in the 64-MDCT group [284 and 267 Hounsfield units (HU) vs. 376 and 359 HU; p < 0.05]; however, no significant differences in the mean vascular enhancement in the ascending aorta, abdominal aorta at the celiac level, and bilateral common femoral arteries were observed between the two groups (p > 0.05 for all). The median IQ scores at the aortic root were higher in the 256-MDCT group than in the 64-MDCT group (3 vs. 4; p < 0.05), and those at the femoral access routes were comparable (4 vs. 4; p = 0.33). The mean effective dose was significantly reduced by 30 % in the 256-MDCT group (23.6 vs. 16.3 mSv; p < 0.05).

CONCLUSION

In preoperative TAVI CT, volume scans using 256-MDCT provide comparable or better vascular enhancement and IQ with a 30 % reduction in CM and radiation dose than those using 64-MDCT.

IMPLICATIONS FOR PRACTICE

Volume scan using 256-MDCT for preoperative TAVI CT may reduce CM and radiation dose in TAVI patients with renal dysfunction.

Impact of Systemic Autoimmune Diseases on Treatment Outcomes and Radiation Toxicities in Patients with Stage I Non-Small Cell Lung Cancer Receiving Stereotactic Body Radiation Therapy: A Matched Case-Control Analysis

We aimed to evaluate the impact of systemic autoimmune diseases (SADs) on treatment outcomes and radiation toxicities following stereotactic body radiation therapy (SBRT) for stage I non-small cell lung cancer (NSCLC). We queried an institution-based database on patients with SADs treated with SBRT for lung cancer between 2001 and 2016 (SAD group). Each patient was matched to three controls without SADs. The primary outcomes of interest were the overall survival (OS) and local control rate (LCR). The secondary outcomes were radiation toxicities of grades ≥2 (≥G2). Twelve patients with SADs were matched to 36 controls. The median follow-up duration was 3.6 years. There was a significant intergroup difference in the OS (hazard ratio [HR]: 4.11, 95% confidence incidence [CI]: 1.82−9.27, p < 0.001) and LCR (HR: 15.97, 95% CI: 2.89−88.29, p < 0.001). However, there were no significant intergroup differences in the odds of acute (odds ratio [OR]: 0.38, 95% CI: 0.02−8.91, p = 0.550) and late (OR: 2.20, 95% CI: 0.32−15.10, p = 0.422) ≥G2 radiation pneumonitis. No other ≥G2 toxicities were identified. In conclusion, although radiation toxicities are not enhanced by SADs, SADs are risk factors of poor prognosis following SBRT for stage I NSCLC.

Modified Glasgow Prognostic Score is predictive of prognosis for non-small cell lung cancer patients treated with stereotactic body radiation therapy: a retrospective study

We aimed to assess the predictive value of the modified Glasgow prognostic score (mGPS) in patients with non-small cell lung cancer (NSCLC) who underwent stereotactic body radiation therapy (SBRT). We retrospectively reviewed the records of 207 patients, with a median age of 79 years. The pretreatment mGPS was calculated and categorized as high (mGPS = 1-2) or low (mGPS = 0). The median follow-up duration was 40.7 months. The five-year overall survival (OS), progression-free survival (PFS) and time to progression (TTP) rates were 44.3%, 36% and 54.4%, respectively. Multivariate analysis revealed that mGPS was independently predictive of OS (hazard ratio [HR] 1.67; 95% confidence interval 1.14-2.44: P = 0.009), PFS (HR 1.58; 1.10-2.28: P = 0.014) and TTP (HR 1.66; 1.03-2.68: P = 0.039). Patients who had high mGPS showed significantly worse OS (33.3 vs 64.5 months, P = 0.003) and worse PFS (23.8 vs 39 months, P = 0.008) than those who had low mGPS. The data showed a trend that patients with high mGPS suffered earlier progression compared to those with low mGPS (54.3 vs 88.1 months, P = 0.149). We confirmed that mGPS is independently predictive of prognosis in NSCLC patients treated with SBRT.

Tumor volume shrinkage during stereotactic body radiotherapy is related to better prognoses in patients with stage I non-small-cell lung cancer

The purpose of the study was to investigate the association between tumor volume changes during stereotactic body radiation therapy (SBRT) and prognoses in stage I non-small-cell lung cancer (NSCLC). This retrospective review included stage I NSCLC patients in whom SBRT was performed at a total dose of 48.0-50.5 Gy in four or five fractions. The tumor volumes observed on computed tomography (CT) simulation and on the CT performed at the last treatment session using a CT-on-rails system were measured and compared. Then, the tumor volume changes during the SBRT period were measured and assessed for their association with prognoses (overall survival, local control, lymph node metastases and distant metastases). A total of 98 patients with a mean age of 78.6 years were enrolled in the study. The T-stage was T1a in 42%, T1b in 32% and T2a in 26% of the cases. The gross tumor volume (GTV) shrank and increased ≥10% in 23 (23.5%) and 36 (36.7%) of the cases, respectively. The 5-year local control and overall survival rates in the groups with a tumor shrinkage of ≥10% vs the group with a shrinkage of <10% were 94.7 vs 70.8% and 85.4 vs 47.6%, respectively; these differences were significant, with a P-value < 0.05. During a short SBRT period, the tumor shrank or enlarged in a small number of cases. A decrease of ≥10% in the GTV during SBRT was significantly related to better overall survival and local control.

Stereotactic body radiotherapy in patients with lung tumors composed of mainly ground-glass opacity

We retrospectively reviewed the effect of stereotactic body radiation therapy (SBRT) in patients with stage I lung cancer whose lung tumor showed a nodular appearance of ground glass opacity, so-called ground glass nodule (GGN). A total of 84 patients (42 men, 42 women; mean age, 75 years) with stage I lung cancer with GGN accompanying a solid component <50% in diameter of the tumor and no metastases were studied. Concerning histology, 32 tumors were adenocarcinoma, 1 was squamous cell carcinoma, 2 were unclassified carcinoma and 49 cases were histology-unproven but increased in size or had a positive finding in 18F-FDG positron emission tomography (PET) examination. The median tumor size was 20 mm (range, 10-41 mm). All of the patients were treated with SBRT, and the total prescribed dose at the isocenter ranged between 48 Gy in four fractions and 84 Gy in ten fractions. Median follow-up duration was 33 months. No patient had local failure nor regional lymph node failure. The 3-year rate of distant failure was 2.6%. Two patients who experienced distant metastases had a past surgical history of initial lung cancer before SBRT. The rates of cause-specific and overall survival at 3 years were 98.2 and 94.6%, respectively. Treatment-related adverse events of ≥grade 4 were not reported. Although more cases and longer follow-ups are mandatory, SBRT may be one of the radical treatment options for patients with GGN.

Assessment of abdominal organ motion using cine magnetic resonance imaging in different gastric motilities: a comparison between fasting and postprandial states

This study assessed abdominal organ motion induced by gastroduodenal motilities in volunteers during fasting and postprandial states, using cine magnetic resonance imaging (cine-MRI). Thirty-five volunteers underwent cine-MRI while holding their breath in the fasting and postprandial states. Gastric motility was quantified by the amplitude and velocity of antral peristaltic waves. Duodenal motility was evaluated as the change of duodenal diameter. Abdominal organ motion was measured in the liver, pancreas and kidneys. Motion was quantified by calculating maximal organ displacement in the left-right, antero-posterior and caudal-cranial directions. Median antral amplitude and velocity in the fasting and postprandial states were 7.7 and 15.1 mm (P < 0.01), and 1.3 and 2.5 mm/s (P < 0.01), respectively. Duodenal motility did not change. Median displacement for all organs ranged from 0.9 to 2.9 mm in the fasting state and from 1.0 to 2.9 mm in the postprandial state. Significant increases in abdominal organ displacement in the postprandial state were observed in the right lobe of the liver, pancreatic head and both kidneys. Differences in the median displacement of these organs between the two states were all <1 mm. Although the motion of several abdominal organs increased in the postprandial state, the difference between the two states was quite small. Thus, our study suggests that treatment planning and irradiation need not include strict management of gastric conditions, nor the addition of excess margins to compensate for differences in the intra-fractional abdominal organ motion under different gastric motilities in the fasting and postprandial states.

Renal Cancer is Not Radioresistant: Slowly but Continuing Shrinkage of the Tumor After Stereotactic Body Radiation Therapy

Purpose:

To evaluate the safety and efficacy of stereotactic body radiation therapy for primary lesion of renal cell carcinoma with long-term and regular follow-up of tumor size and renal function.

Methods:

This prospective study included 13 patients treated with stereotactic body radiation therapy for primary lesion of stage I renal cell carcinoma between August 2007 and June 2016 in our institution. Diagnosis of renal cell carcinoma was made by 2 radiologists using computed tomography or magnetic resonance imaging. A dosage of 60 Gy in 10 fractions or 70 Gy in 10 fractions was prescribed. The higher dose was selected if dose constraints were satisfied. Tumor response on imaging examination, local progression-free rate, overall survival, and toxicity were assessed.

Results:

The mean follow-up period was 48.3 months (range: 11-108 months). The tumors showed very slow but continuous response during long-term follow-up. Three cases (23.1%) showed transient progression during the short follow-up. The mean duration until the day on which partial response was confirmed among the partial or complete response cases was 22.6 months (95% confidence interval, 15.3-30.0 months). Local progression-free rate was 92.3% for 3 years and overall survival rate 91.7% for 2 years and 71.3% for 3 years. Twelve cases (92.3%) had impaired renal function at baseline. Renal function decreased slowly and mildly in most of the cases, but 2 cases of solitary kidney showed grade 4 or 5 renal dysfunction.

Conclusion:

All renal tumors decreased in size slowly but continuously for years after stereotactic body radiation therapy. Renal cancer can be treated radically with stereotactic body radiation therapy as a radiosensitive tumor, but careful attention should be given in cases with solitary kidney.

Serious gastric perforation after second stereotactic body radiotherapy for peripheral lung cancer that recurred after initial stereotactic body radiotherapy: a case report

Background

In recent reports, re-irradiation with stereotactic body radiotherapy for lung tumors in patients previously treated with thoracic radiation therapy resulted in several serious toxicities. Serious non-lung toxicities were observed mostly in patients with central tumors, but we experienced a case of fatal gastric perforation after a second stereotactic body radiotherapy in a patient with a peripheral lung tumor.

Case presentation

An 83-year-old Asian man was diagnosed with T2N0M0 lung cancer in the form of squamous cell carcinoma in the lower lobe of his left lung. He was treated with stereotactic body radiotherapy of 40 Gy in 4 fractions and the tumor decreased in size in partial response. The local tumor recurred 8 months after the first stereotactic body radiotherapy, and he was re-irradiated with a second stereotactic body radiotherapy of 50 Gy in 4 fractions. A Sengstaken–Blakemore tube was inserted below his diaphragm by laparoscopic surgery before the second stereotactic body radiotherapy in order to reduce the stomach dose by keeping his stomach apart from the tumor. Two months after the second stereotactic body radiotherapy, he developed fatal gastric perforation and gastropleural fistula penetrating his diaphragm.

Conclusions

To the best of our knowledge, this is the first report about a gastric perforation after stereotactic body radiotherapy for lung tumors and it warns of serious complication of stereotactic body radiotherapy in not only centrally located but also peripherally located tumors like in this case.

A double three-step theory of brain metastasis in mice: the role of the pia mater and matrix metalloproteinases

The brain is frequently affected by the spread of lung cancer, and haematogenous metastasis is a common route to brain metastasis. We therefore developed an isogenic brain metastasis model of lung cancer to use the Lewis lung carcinoma cell line and analysed dynamics of neoplastic cells after extravasation. Histological analysis revealed two characteristic patterns: metastatic foci exhibiting an angiocentric pattern were designated 'perivascular proliferations'; neoplastic cells infiltrating the brain parenchyma were designated 'invasive proliferations'. Electron microscopic observation of perivascular proliferations showed that neoplastic cells were confined to the perivascular space. In invasive proliferations, however, fragments of collagen fibre were observed in the gaps between neoplastic cells, indicating that the neoplastic cells had disintegrated the pia-glial membrane. We analysed the expressions of matrix metalloproteinase-2 (MMP-2) and MMP-9 by using both immunohistochemical analysis and real-time polymerase chain reaction analysis. MMP-2 expression was significantly higher in invasive proliferations. MMP-9 expression was significantly higher in day 7, but there was no significant difference in day 11. The pia-glial membrane and perivascular space are the barriers that neoplastic cells must overcome to infiltrate the brain. In conclusion, our findings suggest that brain metastasis requires two distinct processes.

Industry forum: Progress in pursuit of therapeutic A2A antagonists: The adenosine A2A receptor selective antagonist KW6002: Research and development toward a novel nondopaminergic therapy for Parkinson's disease

Research and development of the adenosine A2A receptor selective antagonist KW6002 have focused on developing a novel nondopaminergic therapy for Parkinson's disease (PD). Salient pharmacologic features of KW6002 were investigated in several animal models of PD. In rodent and primate models, KW6002 provides symptomatic relief from parkinsonian motor deficits without provoking dyskinesia or exacerbating existing dyskinesias. The major target neurons of the A2A receptor antagonist were identified as GABAergic striatopallidal medium spiny neurons. A possible mechanism of A2A receptor antagonist action in PD has been proposed based on the involvement of striatal and pallidal presynaptic A2A receptors in the "dual" modulation of GABAergic synaptic transmission. Experiments with dopamine D2 receptor knockout mice showed that A2A receptors can function and anti-PD activities of A2A antagonists can occur independent of the dopaminergic system. Clinical studies of KW6002 in patients with advanced PD with L-dopa-related motor complications yielded promising results with regard to motor symptom relief without motor side effects. The development of KW6002 represents the first time that a concept gleaned from A2A biologic research has been applied successfully to "proof of concept" clinical studies. The selective A2A antagonist should provide a novel nondopaminergic approach to PD therapy.

[A case of asymptomatic urachal cyst in autopsy--histopathological study of urachal cyst and review of the literature of 99 cases during a 10 year period in Japan]

Disorders of urachal remnants are common. While urachal cysts are usually asymptomatic, infection may mimic a variety of acute abdomen. Here we report a very rare case of urachal cyst that protruded in the urinary bladder cavity and among 99 accumulated cases, only 4 cases have been reported similar to this case characterized by intravesical development from 1990 to 1999. An uninfected urachal cyst was found in a 79-year-old male who had died of bile duct carcinoma. The cyst showed ovoid protrusion into urinary bladder cavity from the dome (3.5 x 2.0 x 2.0 cm in size). Histopathologically, the cyst wall was thin and consisted of fibrous connective tissue with muscular tissue and peripheral nerve, and lined by cuboidal epithelium but no inflammatory cells could be seen. Urachal cysts occur in both sexes are affected with equal frequency, and frequently occur in a younger population. In clinical symptoms the umbilical manifestations are predominant in patients younger than 30 years old, while the bladder manifestations are predominant in those older than 30.

Double cancer consisting of adenosquamous and hepatocellular carcinomas of the liver

A very rare case of a double cancer consisting of adenosquamous and hepatocellular carcinomas of the liver in a 65-year-old-man is discussed. The patient was hospitalized with epigastralgia in May 1997. Abdominal computed axial tomography revealed a tumor located in the left lobe of the liver and a left hepatic lobectomy was performed. The tumor recurred several months after surgery and the patient died on 4 June 1999. At autopsy, both a major tumor mass with extensive involvement, located in the surgical margin, and a small mass located in S7 were discovered. Microscopically, the major tumor was diagnosed as adenosquamous carcinoma and the small one in S7 as hepatocellular carcinoma. To our knowledge, this is the first case of a double cancer consisting of adenosquamous and hepatocellular carcinomas of the liver. The pathological findings support the hypothesis that this tumor developed as a squamous transformation of adenocarcinoma.

Angiotensin II induces circadian gene expression of clock genes in cultured vascular smooth muscle cells

BACKGROUND

Daily rhythms of mammalian physiology and endocrinology are regulated by circadian pacemakers. The master circadian pacemaker resides in the suprachiasmatic nucleus, which is located in the hypothalamus of the brain, but circadian oscillators also exist in peripheral tissues. Because many studies have demonstrated apparent circadian variations in the frequency of cardiovascular disorders, it is of great interest to investigate a possible relation between circadian gene expression and cardiovascular function. We examined whether a circadian oscillation system exists in the aorta and/or in cultured vascular smooth muscle cells (VSMCs).

METHODS AND RESULTS

The mRNA levels of clock genes were assayed by northern blot analysis. The mouse aorta showed a clear circadian oscillation in the expression of mPer2, dbp, and Bmal1. Brief treatment of VSMCs with angiotensin II induced a robust increase in mPer2 gene expression, followed by a marked reduction in mPer2 mRNA levels and subsequent synchronous cycling of mPer2, dbp, and Bmal1 mRNAs. The induction of mPer2 in VSMCs by angiotensin II was completely abolished by treatment with CV11947, a specific angiotensin II type1 receptor antagonist.

CONCLUSIONS

The present results demonstrate that the aorta and VSMCs possess a circadian oscillation system which is comparable to that of the suprachiasmatic nucleus and that the circadian gene expression in VSMCs is induced by angiotensin II through the angiotensin II type1 receptor. Our in vitro system will provide a useful tool to further analyze the physiological significance of the peripheral clock in cardiovascular function.

Circulatory disturbance of rat spinal cord induced by occluding ligation of the dorsal spinal vein

Spinal cord infarction can be caused by venous disturbances due to trauma or cancer invasion. However, the precise mechanism of venous infarction is not fully understood. To characterize disorders associated with spinal venous occlusion, we performed time-kinetic pathological analyses of rat spinal cord infarction induced by transdural ligation of the dorsal spinal vein at the levels of the T10-T13 vertebrae. One day after ligation congestion, edema and hemorrhage were observed mainly in the dorsal funiculus. Axons were well preserved, but on the 3rd day axonal degeneration became evident. On the 7th day, the necrotic lesion was confined to the dorsal funiculus and was round in shape with foamy macrophage infiltration and astrocytic gliosis. On the 14th day, the involved cord became atrophic, and infiltration of foamy macrophages and astrocytosis became more prominent. After 21-28 days, the infarction focus decreased in size due to gliosis, and residual macrophages were observed. The main lesion was confined to the dorsal funiculus at all times. However, the severity of the softening varied among rats. Thus, we conclude that the disturbance of venous drainage actually results in spinal cord softening. The variability in the lesions is probably due to the presence of unexpected anastomoses of the spinal venous system.

Taurine prevents the decrease in expression and secretion of extracellular superoxide dismutase induced by homocysteine: amelioration of homocysteine-induced endoplasmic reticulum stress by taurine

BACKGROUND

Hyperhomocysteinemia is an independent risk factor for atherosclerosis. Homocysteine has been shown to induce endoplasmic reticulum (ER) stress in vascular endothelial cells. ER stress is a condition in which glycoprotein trafficking is disrupted and unfolded proteins accumulate in the ER. ER molecular chaperons, such as GRP78, are induced and an ER resident kinase, PERK, is activated when cells are subjected to ER stress. Conversely, taurine is reported to have antiatherogenic effects by unknown mechanisms. To elucidate the mechanisms by which homocysteine induces atherosclerosis and taurine prevents it, we examined whether homocysteine and taurine affect the expression and secretion of extracellular superoxide dismutase (EC-SOD), a glycoprotein secreted from vascular smooth muscle cells (VSMCs) that protects the vascular wall from oxidative stress.

METHODS AND RESULTS

We assessed the expression of EC-SOD and GRP78 mRNA in cultured rat VSMCs by Northern blot analysis. The EC-SOD protein secreted into the culture medium was examined by Western blot analysis. Homocysteine (5 mmol/L) and other ER stress inducers, including A23187, were found to decrease EC-SOD mRNA expression and protein secretion. Furthermore, they upregulated GRP78 mRNA expression and activated PERK. Taurine (0.5 to 10 mmol/L), conversely, prevented these actions induced by homocysteine.

CONCLUSIONS

Homocysteine induces ER stress and reduces the secretion and expression of EC-SOD in VSMCs, leading to increased oxidative stress in the vascular wall. Taurine restores the secretion and expression of EC-SOD by ameliorating ER stress induced by homocysteine.

The secretion of amelogenins is associated with the induction of enamel and dentinoid in an ameloblastic fibro-odontoma

Ameloblastic fibro-odontoma is the unique entity of epithelial-ectomesenchymal odontogenic tumors, which is characterized by enamel formation in addition to dentine. We examined immunohistochemically a case of this tumor in which enamel having prism structures was developed in the absence of odontoblast differentiation but was in contact with mesenchymal matrices. Histological examination showed diverse morphological features of epithelial tumor cells, e.g., cuboidal cells comprising tooth bud-like projections, ameloblast- and stellate reticulum-like cells, and residual cells in forms of extended cords or islands of odontogenic epithelium. Immunostaining with anti-amelogenin sera proved that the intracellular production of amelogenins was initiated at the tooth bud-like stage. The secreted amelogenins were detected almost exclusively in the induced enamel and dentinoid areas, as well as in the core region of cementicle-like spheres deposited in the encapsulating stroma. The results obtained indicate that the odontogenic tumor epithelia and its products, i.e., amelogenins, participate in multifaceted aspects of dental hard tissue formation that takes place during oncogenesis.

Corpora amylacea replace the hippocampal pyramidal cell layer in a patient with temporal lobe epilepsy

A 39-year-old woman, with a 23-year history of medically intractable seizures of the complex partial type, underwent a left anterior temporal lobectomy and hippocampectomy. Histologic examinations revealed a massive occurrence of corpora amylacea, neuronal loss, and gliosis in the pyramidal cell layer of the hippocampus. The distribution of corpora amylacea in this case was quite distinctive and unlike the patterns of "nonspecific" corpora amylacea formation seen in aging or other neurodegenerative conditions. The pathogenetic aspects of the accumulation of these peculiar bodies are discussed in relation to hippocampal sclerosis.

Heterochronous development of intrahepatic cholangiocellular carcinoma following hepatocellular carcinoma in a hepatitis B virus carrier

A 68-year-old Japanese woman was admitted to our hospital in September 1995, because of a mass detected by ultrasonography during a follow-up examination for chronic hepatitis B. Hepatocellular carcinoma (HCC) in the right liver lobe was diagnosed based on imaging studies and elevated alpha-fetoprotein (AFP). Percutaneous ethanol injection therapy (PEIT) was performed. PEIT was repeated in November 1998, because the tumor had enlarged and serum AFP was re-elevated. Follow-up ultrasonography (US) demonstrated low echoic mass in the left liver lobe in August 1999; serum AFP was normal, but serum carbohydrate antigen 19-9 (CA19-9) was elevated to 420 U/ml. In October 1999, radiofrequency interstitial tissue ablation (RITA) was performed after tumor biopsy. Pathological findings revealed adenocarcinoma and pathological diagnosis was made as intrahepatic cholangiocellular carcinoma (ICC). Three weeks later, her serum CA19-9 was remarkably decreased (180 U/ml). The patient has been well for 5 months. Her latest AFP and CA19-9 in the serum were 2 ng/ml and 89 U/ml, respectively. The incidence of double cancer in the liver is rare. This is also the first case report to discuss ICC treated with RITA.

Mammary duct ectasia in children presenting bloody nipple discharge: a case in a pubertal girl

Mammary duct ectasia occurs rarely in childhood. The authors report on the case of a pubertal girl who was operated on for duct ectasia with bloody nipple discharge. Duct ectasia is regarded as a primary lesion; it is considered to be a cause of bloody secretion, and it has a mechanism similar to that of mammary duct papilloma.

Synthesis and preliminary evaluation of a carbon-11-labeled adenosine transporter blocker [(11)C]KF21562

We prepared an (11)C-labeled adenosine transporter blocker, [1-methyl-(11)C]-3-[1-(6,7-dimethoxyquinazolin-4-yl)piperidin-4-yl]-1,6-dimethyl-2,4(1H, 3H)-quinazolinedione ([(11)C]KF21652) and examined its potential as a positron emission tomography (PET) ligand for mapping adenosine transporters in the brain and peripheral organs. The log P(7.4) value of KF21652 was 3.14, and the K(i) value was 13 nM for adenosine transporters using [(3)H]nitrobenzylthioinosine as a radioligand. In mice, the highest initial uptake was found in the liver, followed by the kidney and small intestine. The brain uptake was very low. The radioactivity level slightly increased with time in the liver and small intestine, but decreased in the other organs. Coinjection of carrier KF21652 slightly decreased the uptake of [(11)C]KF21562 only in the liver, but not in any other organs. Ex vivo autoradiography of the rat brain showed that [(11)C]KF21652 was scarcely incorporated into the brain. On the other hand, in vitro autoradiography showed the binding of [(11)C]KF21562 to adenosine transporters with high nonspecific binding. These results show that the compound is not a suitable PET ligand for mapping adenosine transporters.

[An operated case of medial temporal lobe epilepsy associated with schizencephaly]

A 24-year-old male of medial temporal lobe epilepsy associated with schizencephaly was presented. He developed complex partial seizure after head trauma at the age of a year and 7 months, which became intractable at the age of 13 year. MRI demonstrated a schizencephalic cleft in the right peri-Rolandic area, cortical dysplasia in the right medical parietal and occipital lobes, and right hippocampal atrophy. Scalp-recorded EEG failed to localize the ictal onset zone. Interictal FDG-PET and ECD-SPECT indicated hypometabolism and hypoperfusion of the right entire temporal lobe, and ictal ECD-SPECT increased perfusion of this area. Chronic subdural electrode recording clearly demonstrated that ictal onset zone was located not on the schizencephalic cleft or its surrounding cortex but on the right medial temporal lobe. Following right anterior temporal lobectomy with hipppocampectomy, seizure control became easy. For the identification of the epileptogenic zone in patients with schizencephaly, chronic subdural electrode recording is mandatory.

De novo acute myeloid leukemia in the elderly; a consistent fraction of long-term survivors by standard-dose chemotherapy

To clarify the characteristics of de novo acute myeloid leukemia (AML) among the elderly, we reviewed 112 patients over 60 years old (median age 72 years) who were treated at hospitals in Nagasaki Prefecture with a population of 1.5 million between 1987 and 1994. Reclassification of morphological diagnosis revealed that the proportion of M3 was lower but that of M6 and the incidence of cases with trilineage dysplasia (TLD), known as poor prognostic features, were higher in the elderly than in patients less than 60 years old. Similarly, chromosomal data showed a lower frequency of favorable karyotypes such as t(8;21) and t(15;17) in the elderly. The overall survival of all 112 patients was 10.3% at 5 years. Multivariate analysis indicated that good performance status (PS), low WBC at diagnosis, standard dose multi-drug chemotherapy and all-trans retinoic acid (ATRA) treatment for M3 patients, and morphological findings without TLD were significantly correlated with longer survival. Most of the long-term survivors were found among those who received standard dose therapy in this series, although no consensus has been established how to treat elderly AML patients. We propose that a prospective controlled trial is necessary to confirm the role of standard dose chemotherapy for elderly patients with de novo AML.

Carbon-11-labeled KF21213: a highly selective ligand for mapping CNS adenosine A(2A) receptors with positron emission tomography

In vivo assessment of the adenosine A(2A) receptors localized in the striatum with positron emission tomography (PET) may offers us a new diagnostic tool for neurological disorders. We evaluated the potential of [7-methyl-(11)C](E)-8-(2,3-dimethyl-4-methoxystyryl)-1, 3,7-trimethylxanthine ([(11)C]KF21213) as a PET ligand for mapping adenosine A(2A) receptors in the central nervous system. KF21213 showed a high affinity for the adenosine A(2A) receptors in vitro (Ki = 3.0 nM) and a very low affinity for the A(1) receptors (Ki > 10,000 nM). In mice, the striatal uptake of [(11)C]KF21213 increased for the first 15 min and then gradually decreased, whereas the uptake in the reference regions such as the cortex and cerebellum rapidly decreased. The uptake ratio of striatum to cortex and striatum to cerebellum increased to 8.6 and 10.5, respectively, at 60 min postinjection. The striatal uptake was significantly blocked by co-injection of carrier KF21213 or each of three other A(2A) antagonists, but not by co-injection of A(1) antagonist. The specific uptake was not detected in the cortex or in the cerebellum. Ex vivo autoradiography and PET clearly visualized adenosine A(2A) receptors in the rat striatum. [(11)C]KF21213 was the most selective tracer for mapping adenosine A(2A) in the central nervous system by PET among the tracers proposed to date.

Mechanomyographic investigation of muscle contractile properties in preadolescent boys

The aim of the present study was to elucidate the muscle contractile properties of preadolescent boys using the mechanomyogram (MMG) and electromyogram (EMG). In 8 preadolescent boys and 10 male young adults, the EMG and MMG were recorded from quadriceps muscles during isometric knee extension contractions at levels of 10 to 80% MVC. The relationship of EMG and MMG to absolute force was approximated by a regression line (r > 0.8). The regression line of the EMG in preadolescent was located above that of the adults, whereas the MMG in both subject groups was fitted by virtually the same regression line. Thus, the MMG seems to be indicative of absolute force in preadolescents as well as young adults. Both groups showed a non-linear increase in the EMG and MMG with relative force (%MVC). The EMG and %MVC relationship was not significantly different between the two groups, whereas the MMG in preadolescents was smaller than that of adults over the range of force studied. The MMG increment with %MVC was more remarkable above 30 or 40% MVC in both groups; however, the rate of the increment in preadolescents was smaller than that in adults. The MMG and %MVC relationship suggests that the muscle contractile properties in preadolescent boys are characterized by immaturity of the fast twitch fibers.

Oral taurine supplementation prevents the development of ethanol-induced hypertension in rats

Taurine is known to lower blood pressure in essential hypertension and some experimental hypertensive models. Taurine has also been reported to activate aldehyde dehydrogenase and to inhibit the elevation of plasma acetaldehyde concentration after ethanol intake. Because acetaldehyde, the first metabolite of ethanol, is suspected to be responsible for many adverse effects of alcohol consumption, we examined the effect of taurine supplementation on ethanol-induced hypertension and abnormalities in the intracellular cation metabolism in Witar-Kyoto rats. In Study 1, systolic blood pressure and intraplatelet free calcium were significantly higher in rats who received 15% ethanol in drinking water than in control rats. Oral taurine supplementation (1% taurine and 15% ethanol in drinking water) completely prevented the development of ethanol-induced hypertension. Intraerythrocyte sodium and intraplatelet free calcium were significantly decreased in taurine-supplemented rats as compared with rats who received 15% ethanol only. In Study 2, hemoglobin-associated acetaldehyde (HbAA) was measured as a marker of protein-bound acetaldehyde. HbAA was significantly elevated in rats who received 5% ethanol in drinking water as compared with control rats. Taurine supplementation (1% taurine and 5% ethanol in drinking water) significantly decreased HbAA. Our findings suggest that the oral supplementation of taurine prevents ethanol-induced hypertension by decreasing protein bound acetaldehyde and altering the cation handling by the membrane.

Further characterization of a CNS adenosine A2a receptor ligand [11C]KF18446 with in vitro autoradiography and in vivo tissue uptake

PET assessment of the adenosine A2a receptors localized in the striatum offers us a potential new diagnostic tool for neurological disorders. In the present study, we carried out in vitro receptor autoradiography of a newly developed PET ligand [11C]KF18446 ([7-methyl-11C]-(E)-8-(3,4,5-trimethoxystyryl)-1,3,7-trimethylxanthin e) with rat brain sections. [11C]KF18446 showed a high striatum/cortex binding ratio (5.0) and low nonspecific binding (<10%), suggesting that [11C]KF18446 has characteristics comparable or slightly superior to [3H]CGS 21680 or [3H]SCH 58261, which are currently available representative A2a receptor ligands. Scatchard analysis indicated a Kd of 9.8 nM and a Bmax of 170 fmol/mm3 tissue in the striatum and a Kd of 16.4 nM and a Bmax of 33 fmol/mm3 tissue in the cortex. Seven xanthine-type and four nonxanthine-type adenosine receptor ligands with an affinity for the adenosine A2a receptors significantly reduced the in vitro binding of [11C]KF18446 to the brain section. The blocking effects were much stronger in the striatum than in the cortex, but did not necessarily parallel their affinity. On the other hand, four xanthine-type ligands and one nonxanthine-type ligand (SCH 58261) of the 11 ligands studied reduced the in vivo uptake of [11C]KF18446 in mice, but other ligands, including A1-selective and nonselective ligands and three nonxanthine-type A2a-selective antagonists did not. We conclude that [11C]KF18446 is a promising adenosine A2a receptor ligand for PET study.

Synthesis of tricyclic compounds as steroid 5alpha-reductase inhibitors

A series of 4-phenoxybutyric acid derivatives attached to a tricyclic skeleton were prepared and evaluated as 5alpha-reductase inhibitors. Structure activity relationships for these compounds in terms of rat epididymis (type 2) 5alpha-reductase inhibitory activities reveal that 1) the substitution pattern at the 11-position of dibenz[b,e]oxepin influenced potency, 2) higher lipophilicity of the tricyclic skeleton improved potency, whereas the existence of a basic nitrogen atom in this skeleton was detrimental to potency, and 3) isobutyl substitution at the 8 positon of the azepine skeleton was tolerated. Among the tricyclic compounds studied, 4-[3-[5-benzyl-8-(2-methyl)propyl-10,11-dihydrodibenz[b,f]azepine- 2-carboxamido]phenoxy]butyric acid (26) was the most potent inhibitor of rat type 2 5alpha-reductase at 0.1 microM.

Enhanced tolerance to light stress of transgenic Arabidopsis plants that express the codA gene for a bacterial choline oxidase

Arabidopsis thaliana was transformed with the codA gene from Arthrobacter globiformis. This gene encodes choline oxidase, an enzyme that converts choline to glycinebetaine. The photosynthetic activity, monitored in terms of chlorophyll fluorescence, of transformed plants was more tolerant to light stress than that of wild-type plants. This enhanced tolerance to light stress was caused by acceleration of the recovery of the photosystem II (PS II) complex from the photo-inactivated state. The transformed plants synthesized glycinebetaine, but no changes were detected in the relative levels of membrane lipids or in the relative levels of fatty acids in the various membrane lipids. Transformation with the codA gene increased levels of H2O2, a by-product of the reaction catalyzed by choline oxidase, by only 50% to 100% under stress or non-stress conditions. The activity of ascorbate peroxidase and, to a lesser extent, that of catalase in transformed plants were significantly higher than in the wild-type plants. These observations suggest that H2O2 produced by choline oxidase in the transformed plants might have stimulated the expression of H2O2 scavenging enzymes, with resultant maintenance of the level of H2O2 within a certain limited range. It appears that glycinebetaine produced in vivo, but not changes in membrane lipids or in the level of H2O2, protected the PS II complex in transformed plants from damage due to light stress.

Increased urinary levels of adrenomedullin in patients with cystitis

In this study, we examined urinary levels of adrenomedullin (AM) in 18 healthy volunteers and 18 patients with cystitis. We also compared urinary levels of AM in 11 patients with cystitis before and after antibiotic treatment. Urinary AM concentrations were measured by a radioimmunoassay specific for human AM. Urinary AM levels in patients with cystitis were significantly elevated compared with those of healthy volunteers and correlated positively with the number of urine leukocytes. By antibiotic treatment, urinary AM levels significantly decreased as compared with before the treatment. By RNA blot analysis of AM transcript, we detected significant levels of AM mRNA in canine urinary bladder and ureter. Intravenous administration of lipopolysaccharide elevated the AM mRNA level in the urinary bladder. These data suggest that infection and inflammation stimulate AM production in the urinary tract, which results in increased urinary AM levels in patients with cystitis. Based on these results, it is deduced that AM participates in the pathophysiology of cystitis, and its urinary level could be used as an index of the degree of cystitis.

Highly active antiretroviral therapy used to treat concurrent hepatitis B and human immunodeficiency virus infections

We report a case of simultaneous infection with hepatitis B virus (HBV) and human immunodeficiency virus type 1 (HIV-1) in a 26-year-old Japanese homosexual man. He was admitted to our hospital for acute hepatitis caused by HBV. At that time, HIV-1antibody (Ab) was not detected in his serum. After 6 months, he was readmitted to our hospital for further examination of his liver because of confined liver enzyme abnormalities. Anti-HIV- Ab was detected in his serum by both enzyme immunosorbent assay (EIA) and particle agglutination (PA). His serum HIV-1 RNA level was 50 x 10(4) copies/ml and serum levels of HBV DNA polymerase (DNA-P) and HBV DNA were 6535cpm and 3 plus (>1000 copies/ml). His clinical course and laboratory data suggested progression from acute to chronic hepatitis related to coinfection with HIV-1. The diagnosis was chronic active hepatitis caused by HBV as an opportunistic infection due to coinfection with HIV-1. We began highly active antiretroviral therapy (HAART) because interferon (IFN) therapy was ineffective. HAART was started at an initial dosage of 600 mg zidovudine (AZT), 300 mg lamivudine (3TC), and 2400 mg indinavir (IDV) daily. After 4 weeks, the serum level of HBV DNA-polymerase (p) had decreased markedly to 37cpm and that of HIV-1 RNA had decreased to below the sensitivity threshold, indicating considerable suppression of the replication of these viruses by the treatment. But HBV DNA remained at low levels. Although the incidence of HBV infection in patients with HIV-1 infection has been reported to be high in the United States and Europe, simultaneous HBV and HIV-1 infection leading to persistent HBV infection is rare.

Effects of early postnatal AF64A treatment on passive avoidance response and radial maze learning in rats

In order to investigate how the selectively lesioned cholinergic system at the early postnatal age influences adult learning behavior, the effects of postnatal administration of ethylcholine mustard aziridinium ion (AF64A), a selective cholinergic neurotoxin, on the acquisition of 2 kinds of learning tasks were examined. Rat pups received an intraventricular injection of AF64A (1.0 or 2.0 nmol) or saline on postnatal day 8, and in adulthood (at 3 months of age), they were tested with the acquisition of passive avoidance response (PAR) and 8-arm radial maze learning. In PAR testing, a significant impairment was observed in male AF64A-treated rats. In addition, in the radial maze task, AF64A-treated rats needed significantly more trials to acquire the task as compared with saline-treated animals. Histological examination after behavioral testings revealed a marked reduction of acetylcholinesterase-stained fibers in the hippocampus and dentate gyrus of the AF64A-treated groups, while there were no detectable changes in the striatum or cerebral cortex. The results suggest that early postnatal AF64A administration induced learning deficits in adulthood which were associated with long-lasting cholinergic denervation in hippocampal formation.

Unique binding pocket for KW-4679 in the histamine H1 receptor

The histamine H1 receptor has an aspartate (Asp) residue in transmembrane helix 3 (TM3), which is well-conserved among biogenic amine receptors. The Asp residue is one of the most crucial amino acids for ligand binding. The tested histamine H1 receptor antagonists with tri- and tetracyclic structures were not selective for histamine H1 receptors and showed affinity for several other biogenic amine receptors. In contrast, KW-4679 ((Z)-11-[3-(dimethylamino)propylidene]-6,11-dihydrodibenz[b, e]oxepin-2-acetic acid hydrochloride), a tricyclic compound, was a selective histamine H1 receptor antagonist. [3H]KW-4679 had high affinity (Kd value of 2.5 +/- 0.12 nM) for wild-type human histamine H1 receptors. In the [3H]KW-4679 binding assay, replacement of Asp107 by alanine by site-directed mutagenesis greatly reduced the affinities (280-2100-fold) of tri- and tetracyclic compounds, whereas this mutation led to a comparatively small reduction (14-fold) in KW-4679 affinity. These results demonstrate that the tested tri- and tetracyclic histamine H1 receptor antagonists which have a tight interaction with the Asp residue are not selective for the histamine H1 receptor. Furthermore, the high selectivity of KW-4679 might be explained by a unique binding pocket, which consists of the Asp residue and other acceptor sites, in the histamine H1 receptor.

A comparative study of physical work load in Japanese and Swedish nursery school teachers

Comparisons were made of general and local physical work loads between two groups of 58 Japanese and 15 Swedish nursery school teachers. Heart rate, number of steps, rating of perceived exertion (RPE), frequency and time expended with respect to trunk flexion, sitting/kneeling, and lifting/carrying loads of 1 kg or more were monitored during working hours. The average percentage heart rate increase in the maximal heart rate range was lower in the Japanese than in the Swedish teachers. However, all parameters of local physical work load indicating musculoskeletal stress were higher in the Japanese than in the Swedish teachers. The RPE was slightly higher in the Japanese than in the Swedish teachers. These features of general and local work load in the Japanese teachers were typically observed among the teachers in charge of very young children (0-2 years). The Japanese teachers in charge of children aged 3-5 years, on the other hand, had similar levels of both general and local work load as the Swedish teachers in charge of classes comprising children of various ages (1-5 years). The physical work load measured in the present study was not sufficient to explain the difference in the magnitude of musculoskeletal problems for nursery school teachers in the two countries, and other factors should now be examined.

Malignant transformation of Nakamura type IV gastric polyp with CA 19-9 production

In a 68-year-old Japanese man, a gastric polyp 24mm in diameter with a stalk 15 mm in diameter was diagnosed as well differentiated adenocarcinoma and treated by endoscopic polypectomy. Histologically, most of the resected tissue was adenoma, and atypical cells were papillarily proliferating to form adenocarcinoma in adenoma, a Nakamura type IV gastric polyp. Infiltration of carcinoma was limited to within the mucosal layer. Immunohistochemical study with anti-CA19-9 antibody revealed positive staining in carcinoma cells. Serum CA19-9 level, which showed slight elevation, returned to the normal range 1 month after the polypectomy. The proliferating cell nuclear antigen (PCNA) labeling index and DNA ploidy pattern were analyzed in the resected tissue. The PCNA labeling index was 30% in carcinoma, 17% in adenoma, and 0.1% in the normal tissue. The DNA ploidy pattern was diploid in adenoma and aneuploid in adenocarcinoma. These findings suggest that gastric adenoma, as well as colonic adenoma, may have the potential for malignant transformation.