Altered Expression of Hepatic CYP1A Enzymes in Rat Hepatocarcinogenesis

Hyperplastic nodules of the liver were induced by treating male F344 rats with a combination of diethylnitrosamine and partial hepatectomy. The livers were examined for the expression of cytochrome P450 (CYP) enzymes, mainly CYP1A1 and CYP1A2; the amount and activity of the enzymes in the nricrosomes were assessed by enzymatic and immunological methods. Levels of CYP1A mRNAs were assayed by Northern blotting. In the liver bearing hyperplastic nodules, the total amount of microsomal CYP enzymes decreased to about 50% of the control. The microsomal activities for the CYP1A2-mediated activation of carcinogenic heterocyclic amines decreased to about 20% of the corresponding controls, in association with decreases in the levels of mRNA and protein of CYP1A2. Furthermore, the inducibility of CYP1A2 by CYP1A inducers such as 3-methoxy-4-aminoazobenzene and 3-methylcholanthrene was also decreased at the mRNA, protein and activity levels. On the other hand, CYP1A1 enzyme, which was undetectable in control rat liver, appeared in the liver bearing hyperplastic nodules, but its inducibility by a CYP1A inducer decreased slightly. The present findings indicated that individual CYP1A enzymes are differently regulated, and the expression of CYP1A2 is reduced preferentially in the liver bearing hyperplastic nodules.     

Serum Bile Acid Levels in Preoperative and Postoperative Patients with Congenital Biliary Atresia

To elucidate the bile acid metabolism in the preoperative and postoperative stages of congenital biliary atresia (CBA), the unconjugated and conjugated bile acid levels in sera were measured by high performance liquid chromatography (HPLC). The results showed that the mean total serum bile acid (TSBA) level in the preoperative cases of CBA was higher, 122.1±39.0 n?mol/1 (1SD), and was about 12 times higher than the level in the age-matched normal controls (9.9±6.0). Even in the non-icteric patients several years after operation, the mean TSBA level was still much higher (15.2±9.6) than that of normal controls (5.7±3.1). The mean ratio of cholic acid to chenodeoxycholic acid (CA/CDCA) in the preoperative and postoperative cases of CBA was less than 1.0. The mean ratio of glycine-conjugated bile acids to taurine-conjugated bile acids (G/T) in the preoperative cases of CBA was the lowest (1.9±1.1). In the clinically good cases with sufficient bile flow after operation, G/T ratio was the highest (9.3±6.5). In the normal controls and the patients with preoperative and postoperative CBA, the main bile acids were glycocholic acid, taurocholic acid, glycochenodeoxycholic acid and taurochenodeoxycholic acid. These conjugated bile acids comprised more than 85% of the total in amount.     

Follicular lymphoma in Osaka,Japan: histological features and chronological change

Follicular lymphoma (FL) is defined as a neoplastic proliferation of follicle center cells with varying follicular areas. To learn the time trend of FL in the Osaka area, an adult T-cell leukemia/lymphoma (ATL) nonendemic area of Japan, we examined the frequency of FL among all non-Hodgkin's lymphomas (NHLs) during the period 1964 to 1987 (n = 1,000) and 1999 to 2001 (n = 659).The frequency of FL with varying follicular areas increased from 1964-1987 to 1999-2001.There was a significant difference in frequency of total cases of FL (14.2% versus 18.8%) (P < .05) and FL with no to 25% follicular area (2.3% versus 5.0%) (P < .01). According to the Berard criteria, cytologic grade of FL was defined by counting the number of centroblasts (CB) in 10 neoplastic follicles as follow: < or = 5 CB per high power field (HPF), grade 1; 6-15 CB, grade 2; >15 CB, grade 3. Immunohistochemical staining with monoclonal antibodies for bcl-2 and CD10 was performed. There was an inverse correlation between follicular area and cytological grade (P < .0001) and bcl-2 expression and cytological grade (P < .01). That is, the larger the follicular area in cases with a lower cytological grade, the stronger was bcl-2 expression in a lower cytological grade. There was a significant correlation between follicular area and stage of disease (P < .05). That is, the follicular area was larger in cases in an advanced stage. This study showed the increase in frequency of FL in Osaka, Japan. Change of lifestyle in Japan may be one of the causative factors for the increase.     

Redo off-pump coronary artery bypass grafting for high risk hemodialysis patients

BACKGROUND: The number of reoperative (redo) coronary artery bypass grafting (CABG) for patients with long-term hemodialysis has been increasing. Off-pump CABG (OPCAB) may decrease risks associated with redo CABG. METHODS: Two patients on chronic hemodialysis with calcification of the ascending aorta underwent redo double coronary OPCAB for the left anterior descending artery (LAD) and the posterior descending artery (PDA) via median sternotomy. The LAD was bypassed with the left internal thoracic artery (LITA). The PDA was exposed with minimum dissection and bypassed with a composite graft of the right internal thoracic artery (RITA) and the saphenous vein (SV). RESULTS: Both patients made a quick recovery with no complications and one had postoperative angiography that showed the patent grafts. Both patients were free from angina pectoris at follow-up of 6 months and 3 months, respectively. CONCLUSION: Redo OPCAB of the LAD and PDA can be performed with minimal dissection via median sternotomy using the LITA and a composite graft of the RITA and SV.     

Nitric oxide-mediated vasodilatory effect of atrial natriuretic peptide in forearm vessels of healthy humans

1. The aim of the present study was to determine whether the vasorelaxant effect of atrial natriuretic peptide (ANP) is, in part, endothelium dependent in humans. 2. We used veno-occlusive plethysmography to measure forearm blood flow (FBF) during intra-arterial infusions of ANP (4, 8, 16, 32 pmol/min per dL forearm tissue volume) before and after the inhibition of nitric oxide (NO) synthesis by N(G)-monomethyl-L-arginine (L-NMMA; 100 micromol) in seven normal healthy subjects. 3. Atrial natriuretic peptide caused a dose-dependent increase in FBF both before and after L-NMMA and significantly reduced the plasma concentration of angiotensin (Ang) II. Administration of L-NMMA significantly diminished the increase in FBF in response to ANP infusion (P < 0.05). 4. These results suggest that the forearm vasodilative response to ANP is modulated, in part, by an endothelium-derived NO-mediated mechanism associated with a decrease in AngII caused by ANP.     

Temporal bone morphometric study on the eustachian tube and its associated structures in patients with chromosomal aberrations

This study characterized phenotypic anomalies of the eustachian tube (ET) and its associated structures in individuals with various chromosomal aberrations (trisomies 13, 18, 21, and 22 and inversion of chromosome 1). The morphological characteristics of the ET and its accessory structures from 10 temporal bone-ET specimens, obtained from 10 individuals with chromosomal aberrations who ranged from the 26th gestational week to 1 year in age, were compared with the same structures from 21 age-matched control subjects without anomalies. The subjects with chromosomal aberrations had a significantly smaller volume of the lateral lamina (LL) of the ET cartilage, a reduced attachment of the tensor veli palatini muscle (TVPM), and, in some cases, a reduced volume of the lumen of the cartilaginous ET. The volume of the medial lamina (ML) of the ET cartilage was normal at birth, but smaller in specimens more than 2 months of age; this finding suggests that the prenatal development was normal, but that the postnatal growth was retarded. The subjects with chromosomal aberrations also displayed a smaller ratio of the volume of the LL to that of the ML (LL/ML ratio). Our results suggest that individuals with various chromosomal aberrations have rather similar anomalies of the ET and its associated structures. We speculate that these anomalies might be closely related to ET dysfunction in these patients.     

Different effects of phencyclidine and methamphetamine on firing activity of medial prefrontal cortex neurons in freely moving rats

Immunohistochemistry detected calcium-binding proteins (CaBPs) in corpuscular and Merkel nerve endings of the rat vibrissa. CaBP-immunoreactive (ir) corpuscular endings were divided into two types: ramified and unramified endings. Ramified endings were subdivided into reticular and Ruffini endings. Unramified endings were identical to longitudinal lanceolate endings which have been described previously. Reticular and unramified endings as well as Merkel endings co-expressed neurocalcin (NC)- and parvalbumin (PV)-immunoreactivity (ir). However, such endings were devoid of peptide 19 (PEP19)-ir. PV-ir Ruffini endings were immunoreactive for PEP19 but not NC. The retrograde tracing method revealed that 34, 21 and 18% of trigeminal neurons which project to the infraorbital nerve exhibited NC-, PEP19- and PV-ir, respectively. In addition, 73 and 36% of the PV-ir neurons showed NC- and PEP19-ir, respectively. The content and co-expression of CaBPs in vibrissal low-threshold mechanoreceptors may depend on their terminal morphology.     

Differential effects of bupivacaine enantiomers,ropivacaine and lidocaine on up-regulation of cell surface voltage-dependent sodium channels in adrenal chromaffin cells

In cultured bovine adrenal chromaffin cells, (+/-)-bupivacaine inhibited veratridine-induced 22Na(+) influx (IC(50) 6.8 microM). The IC(50) of (+)-bupivacaine (2.8 microM) was 6.2-, 7.4-, and 17.1-fold lower than those of (-)-bupivacaine (17.3 microM), (-)-ropivacaine (20.6 microM), and lidocaine (47.8 microM). Chronic (i.e. 3-h) treatment of cells with (+/-)-bupivacaine increased cell surface [3H]saxitoxin ([3H]STX) binding capacity by 48% (EC(50) of 233 microM; t(1/2)=7.4 h), without changing the K(d) value. Treatment for 24 h with either (+)- or (-)-bupivacaine, or (-)-ropivacaine elevated [3H]STX binding, whereas 24-h treatment with lidocaine had no effect. The rise of [3H]STX binding by (+/-)-bupivacaine was prevented by cycloheximide, an inhibitor of protein synthesis, or brefeldin A, an inhibitor of cell surface vesicular exit from the trans-Golgi network; however, (+/-)-bupivacaine did not increase Na(+) channel alpha- and beta(1)-subunit mRNA levels. In cells subjected to (+/-)-bupivacaine treatment (1 mM for 24 h) followed by 3-h washout, veratridine-induced 22Na(+) influx was enhanced, even when measured in the presence of ouabain, an inhibitor of Na(+),K(+)-ATPase. Ptychodiscus brevis toxin-3 potentiated veratridine-induced 22Na(+) influx by 2.3-fold in the (+/-)-bupivacaine-treated cells, as in non-treated cells. These results suggest that lipophilic bupivacaine enantiomers or (-)-ropivacaine acutely inhibit Na(+) channel gating, whereas its chronic treatment up-regulates cell surface expression of Na(+) channels via translational and externalization events.     

Expression of hNP22 is altered in the frontal cortex and hippocampus of the alcoholic human brain

BACKGROUND: Human neuronal protein (hNP22) is a gene with elevated messenger RNA expression in the prefrontal cortex of the human alcoholic brain. hNP22 has high homology with a rat protein (rNP22). These proteins also share homology with a number of cytoskeleton-interacting proteins. METHODS: A rabbit polyclonal antibody to an 18-amino acid epitope was produced for use in Western and immunohistochemical analysis. Samples from the human frontal and motor cortices were used for Western blots (n = 10), whereas a different group of frontal cortex and hippocampal samples were obtained for immunohistochemistry (n = 12). RESULTS: The hNP22 antibody detected a single protein in both rat and human brain. Western blots revealed a significant increase in hNP22 protein levels in the frontal cortex but not the motor cortex of alcoholic cases. Immunohistochemical studies confirmed the increased hNP22 protein expression in all cortical layers. This is consistent with results previously obtained using Northern analysis. Immunohistochemical analysis also revealed a significant increase of hNP22 immunoreactivity in the CA3 and CA4 but not other regions of the hippocampus. CONCLUSIONS: It is possible that this protein may play a role in the morphological or plastic changes observed after chronic alcohol exposure and withdrawal, either as a cytoskeleton-interacting protein or as a signaling molecule.