Changes of Mercury Contamination in Red-Crowned Cranes, Grus japonensis, in East Hokkaido, Japan

Red-crowned cranes (Grus japonensis) are native to eastern Hokkaido (island population), in contrast to the mainland, which migrates between the Amur River basin and eastern China-Korea peninsula. During the 1990s we found that Red-crowned cranes in Hokkaido were highly contaminated with mercury: however, the source was unknown. We investigated the time trend of mercury contamination in Red-crowned cranes. Total mercury levels in the livers and kidneys from cranes dead in the 2000s were lower than those dead in the 1990s. Feather is a major pathway of mercury excretion for many bird species and is used as an indicator of blood mercury level during feather growth. As internal organs from the specimens collected before 1988 were not available, we analyzed the flight feather shavings from stuffed Red-crowned cranes dead in 1959-1987 and found that the mercury level of feathers from cranes dead in the 1960s and 1970s was not more than those from the cranes dead in the 2000s. These results suggest that mercury contamination in Red-crowned cranes in Hokkaido decreased temporally during the 1990s-2000s. This indicates the possible occurrence of some mercury pollution in Red-crowned cranes' habitat in this region in the 1990s or before.     

Coronary artery calcification by computed tomography in epidemiologic research and cardiovascular disease prevention

Both American and European guidelines recommend coronary artery calcification (CAC) as a tool for screening asymptomatic individuals at intermediate risk for coronary heart disease (CHD). These recommendations are based on epidemiologic studies mostly in the United States. We review (1) the use of CAC in primary prevention of CHD in the United States, (2) epidemiologic studies of CAC in asymptomatic adults outside of the United States, and (3) international epidemiologic studies of CAC. This review will not consider clinical studies of CAC among patients or symptomatic individuals. US studies have shown that CAC is a strong independent predictor of CHD in both sexes among middle-aged and old age groups, various ethnic groups, and individuals with and without diabetes and that CAC plays an important role in reclassifying individuals from intermediate to high risk. Studies in Europe support these conclusions. The Electron-Beam Tomography, Risk Factor Assessment Among Japanese and US Men in the Post-World-War-II birth cohort (ERA JUMP) Study is the first international study to compare subclinical atherosclerosis, including CAC among Japanese, Japanese Americans, Koreans, and whites. It showed that as compared with whites, Japanese had lower levels of atherosclerosis, whereas Japanese Americans had similar or higher levels. CAC is being increasingly used as a screening tool for asymptomatic individuals in Europe and the United States. CAC is a powerful research tool, because it enables us to describe differences in atherosclerotic burden across populations. Such research could identify factors responsible for differences among populations, which may improve CHD prevention.     

Utility of three-dimensional transthoracic echocardiography in diagnosis of intermediate atrioventricular septal defect: report of an adult case

We present the case of a 54-year-old male with an intermediate atrioventricular septal defect (AVSD). He was referred to our institute for treatment of shortness of breath. Two-dimensional transthoracic echocardiography demonstrated an ostium primum defect of the atrial septum, a common atrioventricular valve with mild regurgitations, and an interventricular communication, which are the features of complete AVSD. However, three-dimensional transthoracic echocardiography (3D-TTE) could clearly visualize the tricuspid pouch (i.e., persistence of the tissue in the endocardial cushion), a feature of partial AVSD. 3D-TTE appears to be a useful modality for diagnosis of intermediate AVSD.     

Diagnosis of biliary tract and ampullary carcinomas

Diagnostic methods for biliary tract carcinoma and the efficacy of these methods are discussed. Neither definite methods for early diagnosis nor specific markers are available in this disease. When this disease is suspected on the basis of clinical symptoms and risk factors, hemato-biochemical examination and abdominal ultrasonography are performed and, where appropriate, enhanced computed tomography (CT) and/or magnetic resonance cholangiopancreatography (MRCP) is carried out. Diagnoses of extrahepatic bile duct cancer and ampullary carcinoma are often made based on the presence of obstructive jaundice. Although rare, abdominal pain and pyrexia, as well as abnormal findings of the hepatobiliary system detected by hemato-biochemical examination, serve as a clue to making a diagnosis of these diseases. On the other hand, the early diagnosis of gallbladder cancer is scarcely possible on the basis of clinical symptoms, so when this cancer is found with the onset of abdominal pain and jaundice, it is already advanced at the time of detection, thus making a cure difficult. When gallbladder cancer is suspected, enhanced CT is carried out. Multidetector computed tomography (MDCT), in particular — one of the methods of enhanced CT — is useful for decision of surgical criteria, because MDCT shows findings such as localization and extension of the tumor, and the presence or absence of remote metastasis. Procedures such as magnetic resonance imaging, endoscopic ultrasonography, bile duct biopsy, and cholangioscopy should be carried out taking into account indications for these procedures in individual patients. However, direct biliary tract imaging is necessary for making a precise diagnosis of the horizontal extension of bile duct cancer.     

Philadelphia chromosome positive B-cell type malignant lymphoma expressing an aberrant 190 kDa bcr-abl protein

The Philadelphia (Ph) chromosome translocation, t(9:22) (q34;q11) is found in some acute lymphoid leukaemias (ALL) and acute myeloid leukaemias (AML). Although cytogenetically all pH chromosomes appear similar, the 22q11 breakpoints found in acute leukaemias are of two kinds, those within the major breakpoint cluster region (Mbcr-1) of the BCR gene as found in chronic myelogenous leukaemia (CML), and those within the first intron of this gene. In the former group the molecular events are the same as those found in CML, p210 bcr-abl, encoded by 8.5 kb mRNA; however, a new aberrant protein, p190 bcr-abl, is found in the latter group. Ph translocation is also found in a few cases with malignant lymphoma, but it has not been characterized at the molecular level. We describe here a non-Hodgkin's lymphoma case with primary splenic presentation, which showed a complex Ph translocation. Neoplastic cells were of a B-cell origin (HLA-DR+, sIgM+, sIg lambda +, CALLA-). Molecular studies revealed the expression of p190 bcr-abl with no Mbcr-1 rearrangement. Our case indicates that the same Ph translocation as seen in acute leukaemias can be found in haematologic disorders other than leukaemias, suggesting that a c-abl gene activating mechanism may be involved in the pathogenesis of wide spectrum of haematologic malignancies.     

Plasma dopamine concentrations in various types of hypertension

The concentrations of unconjugated plasma dopamine (PDA) were studied in patients with various types of hypertension. Catecholamines were extracted from plasma specimens (1.0-3.0 ml) through an Amberlite CG50 (Li+-form) microcolumn and eluted by a magnesium sulfate - ethanol solution. The elute was then desalinated and deproteinized by the ethanol-treated precipitation procedure and dried in a vacuum oven at 25 degrees C. A fraction of catecholamines was assayed with the modified procedures of the COMT-mediated radio-enzymatic method. This assay system was sensitive enough to permit an accurate measurement of PDA as low as 6.0 pg per ml of plasma without any detectable contamination of the conjugated dopamine. The resting levels of PDA were 10.1 +/- 1.0 pg/ml (mean +/- SEM), 9.5 +/- 1.0 and 13.7 +/- 0.6 in patients with borderline hypertension (BH, n = 25), essential hypertension (EH, n = 22) and renovascular hypertension (RVH, n = 8), respectively. The values in EH patients were significantly smaller than those in age-matched normal controls (13.0 +/- 1.4, n = 14, p less than 0.05). Remarkably increased PDA values were observed in patients with pheochromocytoma (76.5 +/- 25.4, n = 9, p less than 0.01). Significantly raised PDA values were also found in patients with primary aldosteronism (PA, 27.8 +/- 9.0, n = 6, p less than 0.05), while their plasma norepinephrine levels (PNE, 169 +/- 39 pg/ml) tended to be lower than those of normal controls (206 +/- 20), showing an apparent dissociation between the values of PDA and PNE. Upright posture for 15 minutes induced a significant rise in PDA (p less than 0.05) in all subjects except PA patients. The postural changes of PDA, however, were invariably smaller than those of PNE (p less than 0.05). The resting values of PDA in normal, BH and EH patients showed a significant negative correlation with their mean arterial pressures (r = -0.301, n = 61, p less than 0.05) and a positive correlation with those of PNE (r = 0.381, p less than 0.01). There was no correlation between PDA and age in any group studied. These findings indicate that PDA might not be only a precursor fraction of neurotransmitters released from the sympathetic nervous system but could also represent a physiological function of the dopaminergic regulatory system. The varied but distinctive features of PDA status in various types of hypertension suggest the possibility that the peripheral dopaminergic mechanisms play an inherent role in the pathogenesis of hypertension.     

Evidence for further heterogeneity of the receptors for neuropeptide-Y and peptide-YY in tumor cell lines derived from neural crest.

The expression and structure of the receptors for neuropeptide-Y (NPY) and peptide-YY (PYY) were studied in 16 human and rodent tumor cell lines derived from the neural crest by ligand binding and cross-linking techniques using [125I]Bolton-Hunter-NPY, [125I]PYY, and various forms of monoiodinated NPY and PYY. Although NPY-binding sites were observed in most of the tumor cells, PYY-binding sites were found only on the human neuroblastoma cell lines SMS-MSN, SMS-KAN, SK-N-MC, and MC-IXC and the human Ewing's sarcoma cell line SK-ES. The differential labeling of the NPY/PYY receptors on these cell lines suggests that the NPY/PYY receptors are more heterogeneous than previously described as the Y1, Y2, and Y3 receptor subtypes. Cross-linking studies demonstrate that the Y1 and Y2 receptors for NPY/PYY are structurally different (mol wt, 70 and 50 kilodaltons, respectively) and that the 70- and 50-kilodalton receptor proteins are coexpressed in certain tumor cell lines. This could explain at least in part why cell lines show a relative specificity for Y1/Y2 classification, observed as the inhibition by both C-terminal fragments and Y1-specific analogs on the NPY/PYY binding to membrane receptors. Collectively, the present study suggests further heterogeneity of the NPY/PYY receptors and the existence of multiple receptor proteins in the tumor cell lines derived from the neural crest.     

Alanine aminotransferase (ALT) levels in a normal population and interferon therapy in chronic hepatitis C patients with normal ALT

BACKGROUND/AIMS: The aims of this study were to determine the distribution of serum alanine aminotransferase levels in a normal population and to clarify whether interferon treatment is justified in HCV-infected patients with persistently normal alanine aminotransferase levels. METHODOLOGY: The distribution of alanine aminotransferase levels was examined among 949 normal subjects who were negative for hepatitis viruses, denied regular alcohol use. Nineteen patients with chronic hepatitis C and persistently normal alanine aminotransferase levels were treated with alpha interferon (six or ten million units thrice weekly for six months). RESULTS: Peaks of alanine aminotransferase distribution among the normal subjects were seen at 16-20 IU/L and 11-15 IU/L in males and females, respectively. Fourteen of the 19 patients who received interferon treatment had favorable factors of response to interferon (eight with low pretreatment virus load, four with HCV genotype 2 and two with both). A sustained virological response was achieved in eight (57%) of 14, and alanine aminotransferase levels decreased significantly to within the normal range after interferon treatment in six of eight. CONCLUSIONS: Patients with chronic hepatitis C and persistently normal alanine aminotransferase levels should be treated with high doses of interferon if they have favorable factors of response to interferon treatment.