PubMed Health⌕ Search

Biomedical subjects

Kazuyuki Suzuki

Publications and source records attributed to Kazuyuki Suzuki.

At least 19 recordsLinked to original sources

Novel syntheses of chiral beta- and gamma-amino acid derivatives utilizing N-protected (aminoacyl)benzotriazoles from aspartic and glutamic acids.

Friedel-Crafts reactions of N-protected (alpha-aminoacyl)benzotriazoles with hetero- and benzenoid- aromatics give alpha-amino ketones that can be reduced by either triethyl silane or sodium borohydride to form the corresponding beta- and gamma-amino acid derivatives. The preservation of chirality throughout this process is confirmed by chiral HPLC results.

Amino Acids↗

Spatial and chronological differences in hepatitis B virus genotypes from patients with acute hepatitis B in Japan.

Genotypes of hepatitis B virus (HBV) were determined in 485 patients with acute hepatitis B from all over Japan. They were A in 92 (19%), Ba in 26 (5%), Bj in 32 (7%), C in 330 (68%) and D in 5 (1%). Sexual contacts were the main route of transmission in them. Overall, HBV persisted in only 5 of the 464 (1%) followed patients. Genotypes C accounted for more than 68% in northern as well as southern areas, contrasting with genotype A accounting for 34% in and around the Metropolitan areas. During 24 years from 1982 to 2005, genotype A increased from 5% to 33%, while genotype B gradually decreased from 26% to 8%. Fulminant hepatitis was significantly more frequent in infection with genotype Bj (41%) than those with the other genotypes (p<0.01). The core-promoter double mutation (T1762/A1764) and precore stop-codon mutation (A1896) were more frequent in patients with fulminant than acute self-limited hepatitis (57% versus 15% and 58% versus 10%, respectively, p<0.01 for both). In conclusion, genotype A distributes unevenly over Japan, prevails in younger patients through sexual transmission and has increased with years. Furthermore, fulminant outcome was more frequent in patients with genotype Bj than those with the other genotypes.

Journal Article↗

Overweight and obesity increase the risk for liver cancer in patients with liver cirrhosis and long-term oral supplementation with branched-chain amino acid granules inhibits liver carcinogenesis in heavier patients with liver cirrhosis.

We conducted a multicenter, randomized, controlled trial to investigate the effect of long-term oral supplementation with branched-chain amino acids (BCAA) on the event-free survival in 622 patients with decompensated cirrhosis. In the present study, the development of liver cancer was analyzed as an endpoint in particular. Subjects received either treatment with BCAA at 12g/day or dietary therapy containing the matched daily energy and protein intake. A Cox regression analysis was carried out to estimate the hazard ratios for different background factors stratified by treatment group. Liver cancer was noted in 89 patients. The risk for liver cancer was significantly higher for males, patients with concurrent diabetes mellitus, patients with an alpha-fetoprotein (AFP) level of 20ng/mL or higher, patients with higher body mass index (BMI), and patients with lower serum albumin levels. When the BCAA group and the diet group were compared for factors that interacted with the treatment arms, the risk for liver cancer was significantly reduced in the BCAA group with a BMI of 25 or higher and with an AFP level of 20ng/mL or higher. Oral supplemental treatment with BCAA may reduce the risk of liver cancer in cirrhotic patients with these specific factors.

Journal Article↗

Fasting plasma ghrelin levels reflect malnutrition state in patients with liver cirrhosis.

BACKGROUND AND AIM: Ghrelin plays an important role in controlling the feeding and nutritional states by signaling hypothalamic centers. However, the role of ghrelin in cirrhotic patients in the malnutrition state remains unclear. SUBJECTS AND METHODS: Thirty-four patients with liver cirrhosis (LC) and 10 healthy controls (normal controls, NC) were enrolled in this study. Fasting plasma ghrelin levels (desacyl form) were measured using a newly developed ELISA and the relationship among biochemical parameters including plasma leptin, body composition and energy metabolism were evaluated using an indirect calorimeter. RESULTS: Plasma ghrelin levels were slightly but not significantly elevated in patients with LC when compared with NC. Plasma ghrelin levels showed a negative correlation (r=-0.432, p<0.01) with plasma leptin levels and positive correlations with blood urea nitrogen (BUN), creatinine, white blood cell count and C-reactive protein. No correlation with the severity of liver damage based on the classification of Child-Pugh was noted. Plasma ghrelin levels were significantly correlated with body mass index (BMI), arm muscular circumference (AMC), triceps skinfold thickness (TSF) (BMI, r=-0.389, p<0.05; AMC, r=-0.416, p<0.05; TSF, r=-0.459, p<0.01, respectively) and the substrate oxidation rates of glucose (%CHO), fat (%FAT) and non-protein respiratory quotients (npRQ) (%CHO, r=-0.391, p<0.05; %FAT, r=0.438, p<0.01; npRQ, r=-0.411, p<0.05, respectively). Four factors (npRQ, TSF, total bilirubin, BUN) associated with plasma ghrelin levels were identified by multiple regression analysis. CONCLUSIONS: These data suggest that fasting plasma ghrelin levels may be a useful indicator reflecting malnutrition in patients with LC, although renal failure and inflammatory status are also closely associated with plasma ghrelin levels.

Journal Article↗

Influence of genotypes and precore mutations on fulminant or chronic outcome of acute hepatitis B virus infection.

The outcome of acute hepatitis B virus (HBV) infection is variable, influenced by host and viral factors. From 1982 through 2004, 301 patients with acute HBV infection entered a multi-center cross-sectional study in Japan. Patients with fulminant hepatitis (n = 40) were older (44.7 +/- 16.3 vs. 36.0 +/- 14.3 years, P < .0017), less predominantly male (43% vs. 71%, P = .0005), less positive for hepatitis B e antigen (HBeAg) (23% vs. 60%, P < .0001), less infected with subgenotype Ae (0% vs. 13%, P < .05), and more frequently with Bj (30% vs. 4%, P < .0001) than those with acute self-limited hepatitis (n = 261). Precore (G1896A) and core-promoter (A1762T/G1764A) mutations were more frequent in patients with fulminant than acute self-limited hepatitis (53% vs. 9% and 50% vs. 17%, P < .0001 for both). HBV infection persisted in only three (1%) patients, and they represented 2 of the 23 infected with Ae and 1 of the 187 with the other subgenotypes (9% vs. 0.5%, P = .032); none of them received antiviral therapy. In multivariate analysis, age 34 years or older, Bj, HBeAg-negative, total bilirubin 10.0 mg/dL or greater, and G1896A mutation were independently associated with the fulminant outcome. In in vitro transfection experiments, the replication of Bj clone was markedly enhanced by introducing either G1896A or A1762T/G1764A mutation. In conclusion, persistence of HBV was rare (1%) and associated with Ae, whereas fulminant hepatitis was frequent (13%) and associated with Bj and lack of HBeAg as well as high replication due to precore mutation in patients with acute HBV infection.

Acute Disease↗

Analysis of the full-length genome of genotype 4 hepatitis E virus isolates from patients with fulminant or acute self-limited hepatitis E.

It was suggested that hepatitis E virus (HEV) genotype 4 is associated more closely with the severity of hepatitis E than genotype 3, although the virological basis remains unknown. The aim of this study was to examine whether genomic differences among genotype 4 HEVs are responsible for the development of fulminant hepatitis. Full-length sequences of genotype 4 HEVs from three patients with fulminant hepatitis and six patients with acute self-limited hepatitis were determined. The sequences were analyzed with those of 13 genotype 4 HEV isolates whose entire nucleotide sequence is known. Analysis of 22 full-length sequences (fulminant hepatitis, 5; acute hepatitis, 17) revealed that C at nt 1816 and U at nt 3148 (U3148), both of which do not change the amino acid sequences, were significantly associated with fulminant hepatitis (P = 0.0489, respectively). When partial nucleotide sequences containing nt 1816 or nt 3148 were determined in 16 additional HEV isolates of genotype 4, a closer association between U3148 and fulminant hepatitis (P = 0.0018) was observed. The comparison of 86 HEV isolates of all four genotypes showed that U3148 had a stronger association with fulminant hepatitis than other nucleotides at nt 3148 (P = 0.0006). Patients infected with HEV with U3148 had a significantly lower value of the lowest prothrombin activity (P = 0.0293). Nt 3148 is located within the RNA helicase domain, and 22-nt sequence including nt 3148 was well conserved among all genotypes. A silent substitution of U3148 in HEV may be associated with the development of fulminant hepatitis. Further studies are needed to clarify the underlying mechanism.

Acute Disease↗

Prediction of hepatic encephalopathy development in patients with severe acute hepatitis.

To identify factors predicting the development of hepatic encephalopathy, 164 patients with severe acute hepatitis (SAH), defined as acute hepatitis having a prolonged prothrombin time (PT) of < 40% activity but without hepatic encephalopathy, were prospectively observed at 57 major liver centers in Japan. From the data of 65 patients enrolled from 1997 to 1998, a prediction equation was developed by multiple logistic regression analysis and prospectively evaluated using the data of 99 patients since 1999. Of the 164 patients with SAH, 51 (31%) developed hepatic encephalopathy. From the etiologic viewpoint, the percentages of patients developing encephalopathy were highest in non-A-E hepatitis (41.9%). A predictive model, logit(p) = 0.084 x age (year)+ 0.129 x serum total bilirubin (TB, in mg/dL)-0.158 x prothrombin time (%)-2.434, was developed. In conclusion, old age, prolonged PT, elevation of TB, and non-A-E hepatitis are potential risk factors for developing encephalopathy in SAH.

Adult↗

Expression patterns of connexin 26 and connexin 43 mRNA in canine benign and malignant mammary tumours.

The expression patterns of connexin (Cx) genes, encoding gap junctional proteins, are tissue- and cell-specific and, as their expression is mostly suppressed during carcinogenic processes, they are appropriate for monitoring tumour development. In this study, using reverse transcriptase-coupled polymerase chain reaction (RT-PCR), the expression of Cx mRNAs was examined in seven normal canine mammary glands and in 31 mammary gland tumour samples. Cx26 and Cx43 gene expression was studied in all normal tissues using specific Cx26 and Cx43 primers. When the expression patterns of Cx26 and Cx43 genes were analyzed in several types of canine mammary gland tumours, it was noted that it was the loss of Cx26 expression rather than the occurrence of Cx43 expression that was associated with malignancy. These results suggest that Cx26 plays an important role in tumourigenesis of canine mammary gland.

Animals↗

Molecular tracing of Japan-indigenous hepatitis E viruses.

The ancestor(s) of apparently Japan-indigenous strains of Hepatitis E virus (HEV) was probably of foreign origin, but it remains unclear when and from where it made inroads. In this study, 24 genotype 3 and 24 genotype 4 HEV strains recovered in Japan each showed a significant cluster, clearly distinct from those of foreign strains, in the phylogenetic tree constructed from an 821 nt RNA polymerase gene fragment. The evolutionary rate, approximately 0.8 x 10(-3) nucleotide substitutions per site per year, enabled tracing of the demographic history of HEV and suggested that the ancestors of Japan-indigenous HEV had made inroads around 1900, when several kinds of Yorkshire pig were imported from the UK to Japan. Interestingly, the evolutionary growth of genotype 3 in Japan has been slow since the 1920s, whereas genotype 4 has spread rapidly since the 1980s. In conclusion, these data suggest that the indigenization and spread of HEV in Japan were associated with the popularization of eating pork.

Animals↗

Ratio of circulating follistatin and activin A reflects the severity of acute liver injury and prognosis in patients with acute liver failure.

BACKGROUND AND AIM: The activin A-follistatin system is known to play a critical role in hepatocyte regeneration during the repair of liver tissue. However, the relationship between blood levels of these compounds and the severity and prognosis of acute liver injury remains unclear. The aim of this study was to evaluate the clinical significance of circulating activin A and follistatin in patients with acute liver disease. METHODS: Serum activin A and plasma follistatin levels were determined on admission by enzyme-linked immunosorbent assay in 32 patients with acute hepatitis (AH), 23 patients with acute severe hepatitis (ASH) and 16 patients with acute liver failure (ALF). RESULTS: Both serum activin A and plasma follistatin levels were significantly elevated in patients with ASH and ALF when compared with those in patients with AH and normal controls (NC). Although plasma follistatin levels were significantly and positively correlated with serum activin A levels (r = 0.413, P < 0.001), the follistatin and activin A (F/A) ratio showed distinct deviation from NC between AH and ALF patients. The F/A ratio in AH patients was significantly elevated when compared with NC, but was significantly reduced in ALF patients. Furthermore, the F/A ratio in non-surviving ALF patients was significantly lower than that in survivors. Levels of serum activin A and plasma follistatin were significantly and negatively correlated with prothrombin time (PT) and normotest (NT) levels, while the F/A ratio showed significant and positive correlations with PT and NT. CONCLUSIONS: Decreased blood F/A ratio in ALF patients may be a reliable indicator of the severity of acute liver injury and prognosis in ALF.

Activins↗

An overview of regular dialysis treatment in Japan (as of 31 December 2004).

A statistical survey of 3932 nationwide hemodialysis (hereafter, dialysis) facilities was carried out at the end of 2004, and 3882 facilities (98.73%) responded. The population undergoing dialysis at the end of 2004 was 248 166, an increase of 10 456 patients (4.4%) from that at the end of 2003. The number of dialysis patients per million people was 1943.5. The crude death rate of dialysis patients from the end of 2003 to the end of 2004 was 9.4%. The mean age of patients who underwent dialysis in 2004 was 65.8 years, and that of the total dialysis population was 63.3 years. The percentage distribution of patients who underwent dialysis according to a newly underlying disease showed that 41.3% of patients had diabetic nephropathy and 28.1% had chronic glomerulonephritis. The frequency of calcium carbonate use for dialysis patients was 75.1% and that of sevelamer hydrochloride use was 26.2%. The frequency of sevelamer hydrochloride use does not necessarily have a strong correlation with the dose of calcium carbonate. Patients who received high doses of sevelamer hydrochloride tended to have a low concentration of arterial blood HCO(3-). Approximately 15% of dialysis patients used an intravenous vitamin D preparation, generally maxacalcitol. The longer the patients had been on dialysis, the higher the frequency of use of an intravenous vitamin D preparation. When the concentration of serum intact parathyroid hormone (PTH) was more than 200 pg/mL, the frequency of use of an orally administered vitamin D preparation decreased; but that of intravenous vitamin D preparation increased. The percentage of dialysis patients who received percutaneous ethanol injection therapy (PEIT) was 1.4%. The percentage was more than 50% in the patients who had been on dialysis for more than 10 years. The percentage of patients who received PEIT again was 35.0%. The percentage of patients who had been on hemodialysis for more than 10 years and received PEIT again was more than 50%.

Adolescent↗

The effect of 7.2% hypertonic saline solution on the duration of sodium gradient between the cerebrospinal fluid and the venous circulation in the dog.

To determine the duration of water movement from cerebrospinal fluid (CSF) into venous blood by the infusion of 7.2% hypertonic saline solution (HSS), the sodium gradient between venous blood and CSF were examined. Venous sodium concentrations remained higher than that in CSF for duration of 60 min following HSS infusion. By 90 min, the CSF sodium concentration reached the equilibrium with venous sodium concentration. Those data suggests that the duration of time during which water moved from CSF into capillaries in brain by the gradient of sodium concentration was less than 90 min.

Animals↗

The effect of 7.2% hypertonic saline solution on m-mode echocardiographic indices in normovolemic dogs.

This study investigated whether a small volume of 7.2% hypertonic saline solution (HSS) could affect M-mode echocardiographic indices in dogs. HSS induced significant increase in heart rate, stroke volume and cardiac index, when the fluid infusion was completed (P<0.05). In the HSS group, the left ventricular end-diastolic volume index, as an index of preload, significantly increased (P<0.05), whereas left ventricular end-systolic volume index were not altered. HSS induced slight increases in ejection fraction at end of infusion despite significantly differences were not observed. In conclusion, HSS did not induce a demonstrable effect on M-mode echocardiographic indices of systolic function-enhance cardiac contractility, but it caused preload augmentation that may contribute to an abrupt and transient increase in cardiac output just after HSS infusion.

Animals↗

Relationship between trace elements status in mane hair and atrial fibrillation in horse.

To investigate the relationships between trace elements concentrations in hair and atrial fibrillation (AF) in horses, concentrations of nineteen trace elements were detected in hair using the particle induced X-ray emission (PIXE) method. The horses were assigned to either control (n=22, no abnormalities) or AF groups (n=5) based on electrocardiograph findings. The mean concentrations of Ca and Zn in the hair of the AF group were significantly higher than those in the control group. The Zn/Cu ratio of the hair in the AF group (29.8 +/- 5.5) was significantly higher than that in the control group (23.4 +/- 2.2, P<0.05). The results of the present study suggest that there is a relationship between elevated concentrations of Ca and Zn in hair and AF.

Animals↗

[Quality of life in irritable bowel syndrome].

Irritable bowel syndrome (IBS) is a chronic disorder of unknown origin, which is a very common disease and a frequent complaint among patients consulting general practitioners or gastroenterologists. It is primary characterized by abdominal pain, alteration in bowel habit, abdominal discomfort that can significantly affect quality of life (QOL). Measurements of QOL in IBS patients are more complete than a symptomatic score for the evaluation of patient status, which would increase to use as the assessment of therapeutic effects.

Humans↗

Connexin 32 expression reduces malignant phenotype in human A549 adenocarcinoma cells: Implication of Src involvement.

Recent evidence suggests that a member of the gap junction protein family, connexin (Cx) 32, acts as a tumor suppressor gene against lung adenocarcinoma. However, the precise mechanism remains unclear. In this study, we tried to explore the mechanism for the Cx32-dependent tumor-suppressive effect in lung adenocarcinoma. To perform this study, we established a stable clone of the human lung adenocarcinoma cell line, A549 in which the Cx32 gene was expressed. Cx32 expression in A549 cells reduced anchorage-independent growth and development of tumors in a xenograft model. Additionally, Cx32 induced contact inhibition of growth and reduced invasive activity in A549 cells. The tumor-suppressive effects of Cx32 depended on the inhibition of Src activity. These events were confirmed by an Src inhibitor (PP1) and siRNA for Cx32. These results suggest that the Cx32-dependent tumor-suppressive effect in A549 cells is explained by the inhibition of Src activity.

Adenocarcinoma↗

Association of virus infected-T cell in severe hepatitis caused by primary Epstein-Barr virus infection.

BACKGROUND: Infectious mononucleosis owing to primary Epstein-Barr virus (EBV) infection sometimes causes hepatitis, which is usually self-limiting with mildly elevated transaminases, but can rarely develop into severe hepatitis with jaundice. OBJECTIVE: To clarify the pathogenesis of severe hepatitis by primary EBV infection. METHODS: We experienced four cases of severe hepatitis with jaundice caused by primary EBV infection. These cases were analyzed virologically and histologically, and compared with infectious mononucleosis patients without jaundice. RESULTS AND DISCUSSION: Using real-time PCR, more EBV-DNA was detected in peripheral blood from patients with severe hepatitis, as compared to those without jaundice. Furthermore, CD3+, CD4+ or CD8+ cells contained more EBV DNA than did other cell populations, indicating that in severe hepatitis, T cells harbor most of the EBV. By contrast, mainly B cells were infected in infectious mononucleosis patients without jaundice. The liver was biopsied in three of the four cases. An in situ hybridization study showed that EBV infected lymphocytes, not hepatocytes. In addition, in one patient, it was confirmed that the infected lymphocytes were CD8+ T cells. These results suggest that a large EBV burden and T cell infection may play major roles in the mechanism of severe hepatitis caused by primary EB virus infection.

Adolescent↗

Liver cirrhosis induced by long-term administration of a daily low dose of amiodarone: a case report.

The anti-arrhythmic agent amiodarone (AD) is associated with numerous adverse effects, but serious liver disease is rare. The improved safety of administration of daily low doses of AD has already been established and this regimen is used for long-term medication. Nevertheless, asymptomatic continuous liver injury by AD may increase the risk of step-wise progression of non-alcoholic fatty liver disease. We present an autopsy case of AD-induced liver cirrhosis in a patient who had been treated with a low dose of AD (200 mg/d) daily for 84 mo. The patient was a 85-year-old male with a history of ischemic heart disease. Seven years after initiation of treatment with AD, he was admitted with cardiac congestion. The total dose of AD was 528 g. Mild elevation of serum aminotransferase and hepatomegaly were present. Liver biopsy specimens revealed cirrhosis, and under electron microscopy numerous lysosomes with electron-dense, whorled, lamellar inclusions characteristic of a secondary phospholipidosis were observed. Initially, withdrawal of AD led to a slight improvement of serum aminotransferase levels, but unfortunately his general condition deteriorated and he died from complications of pneumonia and renal failure. Long-term administration of daily low doses of AD carries the risk of progression to irreversible liver injury. Therefore, periodic examination of liver function and/or liver biopsy is required for the management of patients receiving long-term treatment with AD.

Aged↗