Test performances of three diagnostic procedures in evaluating thyroid nodules: physical examination, ultrasonography and fine needle aspiration cytology

A retrospective study was performed to determine the reliability of physical examination (PE), ultrasonography (US) and fine-needle aspiration cytology (FNA) in the evaluation of thyroid nodules. Preoperative diagnoses of 252 euthyroid patients comprised 126 with benign lesions, 114 with papillary carcinoma and 12 with follicular carcinoma made by PE, US and FNA were reviewed. The specificity of PE, US and FNA for malignancy was 98%, 90% and 98%, respectively. The sensitivity of PE, US and FNA for malignancy was 63%, 78% and 80%. The sensitivity for papillary carcinoma of the three procedures was 68%, 83%, 88%, whereas that for follicular carcinoma was 25%, 25%, 8%, respectively. When all the test results were negative, the likelihood ratio favoring papillary carcinoma was 0.008 whereas that favoring follicular carcinoma was 0.6. The histological category of carcinoma should be considered when evaluating diagnostic procedures for thyroid nodules. No negative test result is conclusive for ruling out the possibility of follicular carcinoma.

Effects of phenylephrine on membrane currents in single smooth muscle cells of taenia caeci

Procedures used for dissociation of taenia caeci smooth muscle cells usually damage alpha 1-adrenoceptors. This paper describes modes of isolation under which alpha 1-adrenoceptors of taenia caeci do not lose their function. It has been found that antioxidants (dithiothreitol or taurine) are able to protect receptors from injury caused by digestive enzymes. A high concentration of bovine serum albumin also protects receptors from enzyme injury if a relatively specific enzyme (collagenase Type XI, Sigma) is used. Phenylephrine (10 mcmol/l) studied both in muscle strips using the double sucrose gap method and in isolated smooth muscle cells using whole cell current clamp conditions substantially hyperpolarized the smooth muscle membrane. This hyperpolarization was blocked by pretreatment of the tissues or cells by prazosin (1 mcmol/l). Phenylephrine (1-50 mcmol/l), under whole cell patch clamp conditions, enhanced the frequency and amplitude of spontaneous transient outward currents (STOCs), which were voltage- and temperature-dependent, and elicited a low amplitude sustained outward current. Phenylephrine (10 mcmol/l) reduced the inward and enhanced the outward component of the total whole cell current evoked by voltage steps from the holding potential of -50 mV to -10 mV. Under experimental conditions when only calcium current was recorded, phenylephrine significantly enhanced its amplitude. These results are in favor of the assumption that phenylephrine induced hyperpolarization is at least partially the consequence of calcium influx, which activates potassium conductance.

Role of iron and glutathione redox cycle in acetaminophen-induced cytotoxicity to cultured rat hepatocytes

The aims of this study were to investigate the roles of iron as a catalyst in reactive oxygen metabolite-mediated cellular injury and of the endogenous antioxidant defenses against acetaminophen-induced cytotoxicity in cultured rat hepatocytes. Hepatocytes were isolated and cultured from either 3-methylcholanthrene-treated or untreated rats. Cytotoxicity was evaluated by measuring 51Cr and lactate dehydrogenase release. Acetaminophen caused dose-dependent cytotoxicity in 3-methylcholanthrene-treated, but not untreated, cells. There was a good correlation between 51Cr and lactate dehydrogenase release values. Pretreatment with both diethyl maleate, which covalently binds glutathione as catalyzed by glutathione-S-transferase, and bis(chloroethyl)-nitrosourea, an inhibitor of glutathione reductase, enhanced acetaminophen-induced cytotoxicity. Inhibition of endogenous catalase activity by pretreatment with aminotriazole did not affect acetaminophen-induced cellular damage. Addition of exogenous catalase failed to protect against acetaminophen-induced cytotoxicity. Preincubation with both deferoxamine, a ferric iron chelator, and phenanthroline, a ferrous iron chelator, diminished acetaminophen-induced cytotoxicity. These results indicate that iron is crucial in mediating acetaminophen-induced cytotoxicity and that the glutathione redox cycle, but not catalase, plays a critical role in the endogenous defenses against acetaminophen-induced cellular damage in cultured rat hepatocytes in vitro.

[Flumazenil antagonism of midazolam-induced respiratory depression]

Flumazenil, a benzodiazepine antagonist, reliably reverses midazolam-induced sedation, but its effect on respiratory depression has not been clarified completely. Ten healthy male volunteers received midazolam 0.1 mg.kg-1. Then they received flumazenil 0.5 mg (n = 9) and 1.0 mg (n = 1), intravenously. Rib-cage (RC) and abdominal wall (ABD) movement was measured by mercury-in-silastic strain gauge. Nasal air flow (FLOW), genioglossal electromyogram (EMG) and oxygen saturation (SaO2) were recorded simultaneously. Midazolam caused significant increases of RC movement and respiratory rate, and decreases of ABD movement, FLOW, EMG and SaO2. After administration of flumazenil, although respiratory rate returned to the pre-midazolam values, RC movement decreased on the contrary. ABD movement, FLOW, EMG, SaO2 did not recover to the pre-midazolam values. These data suggest that flumazenil 0.5 mg reverses midazolam-induced sedation completely, but is partially effective for some parameters related to respiratory depression.

Polygalacturonase-inhibiting protein accumulates in Phaseolus vulgaris L. in response to wounding, elicitors and fungal infection

Polygalacturonase-inhibiting protein (PGIP) is a cell wall-associated protein that specifically binds to and inhibits the activity of fungal endopolygalacturonases. The Phaseolus vulgaris gene encoding PGIP has been cloned and characterized. Using a fragment of the cloned pgip gene as a probe in Northern blot experiments, it is demonstrated that the pgip mRNA accumulates in suspension-cultured bean cells following addition of elicitor-active oligogalacturonides or fungal glucan to the medium. Rabbit polyclonal antibodies specific for PGIP were generated against a synthetic peptide designed from the N-terminal region of PGIP; the antigenicity of the peptide was enhanced by coupling to KLH. Using the antibodies and the cloned pgip gene fragment as probes in Western and Northern blot experiments, respectively, it is shown that the levels of PGIP and its mRNA are increased in P. vulgaris hypocotyls in response to wounding or treatment with salicylic acid. Using gold-labeled goat-anti-rabbit secondary antibodies in EM studies, it has also been demonstrated that, in bean hypocotyls infected with Colletotrichum lindemuthianum, the level of PGIP preferentially increases in those cells immediately surrounding the infection site. The data support the hypothesis that synthesis of PGIP constitutes an active defense mechanism of plants that is elicited by signal molecules known to induce plant defense genes.

[Effects of sevoflurane or halothane on contractile responses of isolated canine basilar artery]

Although volatile anesthetic is known as a cerebral vasodilator, its mechanism is not clear. The purpose of this study was to investigate effects of sevoflurane or halothane on contractions induced by high K+ and serotonin in the isolated canine basilar artery. Cylindrical segments of canine basilar artery were placed in Krebs solution oxygenated with 95% O2 and 5% CO2 at 37 degrees C. They were then constricted with cumulative administration of 10 to 60 mM KCl, or with 10(-9) to 10(-6) M serotonin and exposed to either sevoflurane or halothane at concentration of 1.0 and 2.0 MAC. Halothane and sevoflurane at concentration of 1.0 and 2.0 MAC decreased contractile responses evoked by KCl to a similar degree. The attenuation by either of the two anesthetics at concentration of 2.0 MAC were equivalent to the inhibitions by diltiazem 2 x 10(-7) M. Contractile responses to serotonin above 3 x 10(-7) M were depressed by halothane 1.0 MAC, but not by sevoflurane 1.0 MAC. Sevoflurane and halothane at concentration of 2.0 MAC decreased contractile responses evoked by serotonin at concentrations above 3 x 10(-8) M and 10(-8) M. Removal of the endothelium did not alter the response of the basilar artery contracted by serotonin to either anesthetic. These findings suggest that sevoflurane and halothane depress the voltage-dependent Ca2+ channels due to decreases of contractile responses to high K+. Our results also demonstrate that sevoflurane is a less potent vasodilator of the basilar artery contracted by serotonin than halothane.

Neonatal assessment using the Apgar fuzzy expert system

We applied fuzzy theory to the Apgar scoring system (APG) to devise an Apgar fuzzy expert system (AFES). Three AFESs were determined separately by each one of three doctor groups (four inexperienced obstetricians, four experienced obstetricians and four expert neonatologists) in order to demonstrate that the AFES reflected the examiner's expertise and situation. Two-hundred and sixty-seven neonates were assessed 1 min after birth by an experienced obstetrician using the APG and the three AFESs. Statistical analysis of the relationship between the APG and the three AFESs in the acidosis group showed that the AFES determined by four expert neonatologists had the highest sensitivity and were significantly different (p < 0.05) from the APG. The AFES determined by the four expert neonatologists was revealed to be a valuable tool.

Molecular and biological characterization of fusion regulatory proteins (FRPs): anti-FRP mAbs induced HIV-mediated cell fusion via an integrin system

Anti-FRP mAbs induced polykaryocyte formation of U2ME-7 cells (CD4+U937 cells transfected with the HIV gp160 gene). Anti-FRP-1 mAb immunoprecipitated gp80-85, gp120 and homodimers of these peptides, and anti-FRP-2 mAb reacted with gp135 identically to the alpha 3 subunit of integrin. Both anti-FRP-1 and anti-FRP-2 mAb-induced cell fusion was blocked by anti-beta 1 integrin antibody, fibronectin or inhibiting anti-FRP-1 antibody. Therefore, anti-FRP mAbs were thought to induce the fusion via an integrin system(s). FRP-mediated fusion was temperature, cytoskeleton, energy and Ca2+ dependent. These experiments showed a possible regulatory function of cell fusion by an integrin system(s).

Transport mechanism of an H1-antagonist at the blood-brain barrier: transport mechanism of mepyramine using the carotid injection technique

The blood-brain barrier (BBB) permeability of mepyramine was measured by the carotid injection technique to elucidate the transport mechanism of an H1-antagonist in the central nervous system. Mepyramine was found to enter the brain by saturable and carrier-mediated transport. The in vivo kinetic parameters were estimated as follows: the maximum uptake rate (Jmax) was 7.12 +/- 1.37 mumol/min/g of brain, the Michaelis constant (Kt) was 4.40 +/- 2.00 mM, and the nonsaturable first order rate (Kd) was 0.28 +/- 0.02 ml/min/g of brain. The mepyramine transport was not inhibited either by nutrients or by choline, hemicholinium-3, though it was inhibited by the classical H1-antagonists such as diphenhydramine, diphenylpyraline, and also by propranolol. The above inhibitory effects suggest that a transport system different from the amine transport system exists for the BBB transport of mepyramine, and that this transporter is common not only for H1-antagonists but also for basic drugs.

Multiple subcellular localization of bcl-2: detection in nuclear outer membrane, endoplasmic reticulum membrane, and mitochondrial membranes

The use of biochemical fractionation, immunofluorescence laser-scanning confocal microscopy, and immunoelectron microscopy with mouse anti-human bcl-2 monoclonal antibody to analyze the subcellular localization of the bcl-2 gene product revealed the protein prominently in the nuclear envelope, endoplasmic reticulum membrane, and mitochondrial membranes. Electron microscopy at high magnification more precisely localized bcl-2 to the nuclear outer membrane as confirmed by the biochemical fractionation, as well as to mitochondrial outer and, to a lesser degree, inner membrane. This multisite membrane distribution of bcl-2 suggests an important role for this protein in several different membrane compartments.

Contraction and depolarization induced by fetal bovine serum in airway smooth muscle

We investigated the effects of fetal bovine serum (FBS) on the resting membrane potential and muscle tone of canine airway smooth muscles using tension recording and microelectrode methods. At concentrations > 0.1%, FBS induced a sustained increase in muscle tone. At concentrations > 1%, FBS depolarized the resting membrane potential of dog trachea in a dose-dependent manner. When FBS was dialyzed, it failed to induce a sustained increase in muscle tone or to depolarize the membrane, indicating that FBS contained factor(s) that induced contraction of dog airway smooth muscles. When FBS was dialyzed against distilled water, the outer solution which was freeze dried and then reconstituted (> 1% in original vol) induced a sustained increase in muscle tone, indicating that FBS contained dialyzable factor(s) that increased muscle tone and depolarized the resting membrane potential of dog airway smooth muscles. Methysergide (10(-6) M) or cyproheptadine (10(-6) M), nonspecific antagonists to serotonin receptors, 5-hydroxytryptamines (5-HT1 and 5-HT2), markedly reduced the FBS-induced increase in the muscle tone to approximately 20% of the original value but did not abolish the response. On the other hand, methysergide (10(-6) M) completely suppressed the increase in the muscle tone evoked by peak fractions obtained by application of the dialysate of FBS or 5-HT to a C18 reverse-phase column, indicating the peak fractions contained only 5-HT. These observations indicate that FBS contained 5-HT and an unknown factor(s) responsible for increase in the muscle tone of the airway smooth muscle induced by FBS.

PEBP2 alpha B/mouse AML1 consists of multiple isoforms that possess differential transactivation potentials

A murine transcription factor, PEBP2, is composed of two subunits, alpha and beta. There are two genes in the mouse genome, PEBP2 alpha A and PEBP2 alpha B, which encode the alpha subunit. Two types of the alpha B cDNA clones, alpha B1 and alpha B2, were isolated from mouse fibroblasts and characterized. They were found to represent 3.8- and 7.9-kb transcripts, respectively. The 3.8-kb RNA encodes the previously described alpha B protein referred to as alpha B1, while the 7.9-kb RNA encodes a 387-amino-acid protein, termed alpha B2, which is identical to alpha B1 except that it has an internal deletion of 64 amino acid residues. Both alpha B1 and alpha B2 associate with PEBP2 beta and form a heterodimer. The alpha B2/beta complex binds to the PEBP2 binding site two- to threefold more strongly than the alpha B1/beta complex does. alpha B1 stimulates transcription through the PEBP2 site about 40-fold, while alpha B2 is only about 25 to 45% as active as alpha B1. Transactivation domain is located downstream of the 128-amino-acid runt homology region, referred to as the Runt domain. Mouse chromosome mapping studies revealed that alpha A, alpha B, and beta genes are mapped to chromosomes 17, 16, and 8, respectively. The last two genes are syntenic with the human AML1 on chromosome 21q22 and PEBP2 beta/CBF beta on 16q22 detected at the breakpoints of characteristic chromosome translocations of the two different subtypes of acute myeloid leukemia. These results suggest that previously described chimeric gene products, AML1/MTG8(ETO) and AML1-EAP generated by t(8;21) and t(3;21), respectively, lack the transactivation domain of AML1.

[Re-examination of the criteria for clinical evaluation on bacterial prostatitis--analysis of the data of the clinical study of temafloxacin]

The clinical efficacy of temafloxacin (TMFX) was evaluated in the patients with acute prostatitis (AP: 31 cases) and chronic prostatitis (CP: 75 cases), and the criteria for clinical evaluation on bacterial prostatitis by the Japanese UTI Committee were re-examined. The clinical efficacy of TMFX on prostatitis was examined. The number of the evaluable cases by doctors in charge were 30 and 68 for AP and CP, respectively. The efficacy rates were as high as 96.7% for AP and 80.9% for CP. In the patients whose efficacy could be evaluated by the Committee, the efficacy rates were as high as 100% (15/15) for acute bacterial prostatitis (ABP) and 66.7% (18/27) for chronic bacterial prostatitis (CBP). The bacteriological eradication rates were 100% (15/15) for ABP and 81.5% (22/27) for CBP. Adverse drug reactions were observed in 8 of 100 cases (total evaluable cases) but they clinically did not consist any problems. Abnormal laboratory test findings were observed in 9 of 71 cases (total evaluable cases), whose changes were all slight and did not clinically cause any problem. Therefore, TMFX was concluded to be highly useful in the treatment of ABP and CBP. The criteria for clinical evaluation on bacterial prostatitis were re-examined. Concerning the treatment period, comparison of the evaluation at Day 7 with that at Day 14 in ABP revealed that the efficacy was evaluable at Day 7. In the same way, comparison of the evaluation at Day 14 with that at Day 28 in CBP revealed that the efficacy was evaluable at Day 14. Concerning the pathogens, in ABP, the major pathogens were considered to be GNR as well as E. coli. On the other hand, in CBP, GNR and E. faecalis, that were generally authorized to be pathogens, were detected in less than half of the patients, and CNS were detected in the other patients. Among the CNS cases, there were some cases that showed no relationship between improvement of clinical symptoms and bacterial response. Therefore, it is necessary to perform further studies on this matter. In conclusion, regarding the criteria for clinical evaluation on bacterial prostatitis proposed by the Japanese UTI committee, the treatment period for evaluation of efficacy was appropriate, and it is necessary to perform further studies in order to determine the pathogens in bacterial prostatitis.

[A case of dural arteriovenous malformation in the anterior cranial fossa presenting with intracranial hemorrhage]

We report a case of dural arteriovenous malformation (dAVM) in the anterior cranial fossa presenting with intracranial hemorrhage. The patient was a 60-year-old man who became unconscious shortly after developing an acute headache. Computed tomography performed on admission demonstrated a left frontal intracranial hematoma together with subarachnoid hemorrhage and a subdural hematoma. Cerebral angiography revealed a dAVM in the left anterior cranial fossa supplied by the anterior ethmoidal arteries bilaterally from enlarged ophthalmic arteries and which drained into the superior sagittal sinus via a dilated cortical vein with aneurysmal dilatation. The lesion was successfully resected via a left frontal craniotomy. Although reports of dAVMs in the anterior fossa are rare, a number of new cases have been described recently. The clinical features and angiographic findings in 58 cases are analyzed. The average age at the time the patients presented was 55.8 years, and males predominated (85.0%). Intracranial hemorrhage was the presenting manifestation in most cases (74.1%). Ocular symptoms occurred especially in cases with a posterior venous drainage pattern. Angiographically, the dAVM was most frequently supplied by the anterior ethmoidal artery (94.8%) and drained into a pial vein with vascular sac in almost every case. Rupture of this varicose dilatation often caused intracranial hemorrhage. The main drainage sinus or vein was usually the superior sagittal sinus (86.0%). The nidus was usually in the dura mater, but recently a nidus in the brain parenchyma has also been reported. The pathogenesis of this entity remains unclear, but some impairment of normal embryonic vascular development is the most likely etiology. Surgical resection remains the treatment of choice.

Differentiation between parasystole and extrasystoles. Influence of vagal stimulation on parasystolic impulse formation

Recently, it has been shown that when a sinus impulse falls late in the parasystolic cycle, it usually hastens the next ectopic discharge. Thus, in many cases, the classic criteria for the diagnosis of parasystole (ie, varying coupling intervals and constant shortest interectopic intervals) cannot be used. To differentiate between parasystole and extrasystoles in such cases, the influence of vagal stimulation on parasystolic impulse formation was investigated in seven cases of "true" parasystole in which one or more "pure" ectopic cycles without any intervening nonectopic QRS complexes were found spontaneously. In all cases pure ectopic cycles were found during sinus arrest caused by vagal stimulation; namely, none of the cases showed extreme prolongation of the parasystolic cycle. These results strongly suggest that instead of the classic criteria, vagal stimulation causing temporary sinus arrest is the optimal method for differentiation between parasystole and extrasystoles in cases without spontaneous pure ectopic cycles.

[Effects of sevoflurane on contraction, membrane ionic currents and intracellular cyclic AMP concentration in canine single ventricular cells]

The effects of sevoflurane (SV) on contraction, membrane ionic currents and intracellular cAMP concentration were studied in single canine ventricular cells. The authors demonstrated first that SV depressed contractile response of single ventricular cells in a dose-dependent manner. In electrophysiological studies, SV depressed the plateau height and duration of action potentials. Whole-cell voltage clamp experiments revealed that SV depressed voltage-dependent Ca2+ currents in a dose-dependent manner but SV (1%, 2%) did not change Na+ currents. Further, SV (1%, 2%) did not reduce intracellular cAMP concentrations. We conclude that the decrease of myocardial contractile response in single canine cardiac cells by SV is mainly due to the inhibition of voltage-dependent L-type of Ca2+ channels at the sarcolemma and not through changes in intracellular cAMP levels.

Correlations of C1q- and C3d-bearing circulating immune complexes with immunopathological disease activity in lupus nephritis patients

The serum levels of circulating immune complexes (CIC) measured by three different types of enzyme immunoassay (EIA) using monoclonal anti-C1q and antibodies and C1q as solid phase reagents were compared with clinical disease activity and immunohistological glomerular lesions in 29 SLE patients. Three types of CIC measured by these assays (anti-C1q CIC, anti-C3d CIC and C1q SP CIC) showed significantly higher levels in patients than in controls and were significantly associated with the clinical and serological disease activities. Anti-C1q CIC showed good correlation not only with mesangial IgG depositions (P < 0.01), but also with that of C1q (P < 0.05). C1q SP CIC also showed a weak correlation with mesangial C1q deposition (P < 0.05). Serum levels of anti-C3d CIC increased with the degree of mesangial IgG and complement depositions. Analysis of the clinical course of a patient with active SLE revealed a more rapid decrease of anti-C1q CIC and anti-C3d CIC along with the improvement of disease activity, including the mesangial lesion, than that of C1q SP CIC. According to these results, the CIC detected with assays using monoclonal antibodies against complement fragments, especially the anti-C1q assay, is likely to provide specific information regarding the clinical, serological and immunohistological disease activity in lupus nephritis.

Stimulation of polyomavirus DNA replication by wild-type p53 through the DNA-binding site

The tumor suppressor p53 possesses characteristics of a transcription factor; it binds to specific DNA sequences and activates transcription from various promoters. Here we found that murine wild-type p53 stimulated not only transcription but also polyomavirus (Py) DNA replication in a sequence-dependent manner. Oncogenic mutant p53, lacking the DNA-binding activity, showed no stimulation of Py DNA replication. Deletion of the N-terminal acidic transactivation domain of wild-type p53, which completely eliminated the ability to stimulate transcription, only impaired the function to stimulate Py DNA replication. The replication-stimulating activity of wild-type p53 was impaired by the deletion of the C-terminal oligomerization domain as well, without affecting the ability to stimulate transcription. The region responsible for the sequence-specific DNA-binding activity mapped to the central portion of the p53 molecule has a minimal activity. The results indicate that both the N-terminal and the C-terminal regions significantly contribute to the p53-mediated stimulation of Py DNA replication.

[Autologous vs bovine pericardial valved patch for widening of the right ventricular outflow tract of tetralogy of Fallot]

Autologous or glutaraldehyde treated bovine pericardial valved patch was utilized for widening of the right ventricular outflow tract in 20 patients with tetralogy of Fallot (autologous pericardium group in 10 patients and bovine pericardium group in 10). Pericardial valve function of the both materials was evaluated by postoperative cardiac catheterization performed 1 year after the operation. There were no significant differences in pulmonary arterial and right ventricular pressures, and right ventricular ejection fraction and end-diastolic volume between the 2 groups. Pulmonary angiogram in the autologous pericardium group patients demonstrated the pulmonary regurgitation (PR) of grade 1 in 5 patients, grade 2 in 4 and grade 3 in 1. On the other hand, 1, 3 and 6 patients in the bovine pericardium group demonstrated no-PR, grade 1 PR and grade 2 PR, respectively. It was concluded that there were no significant differences between autologous and glutaraldehyde treated bovine pericardium as a material of valved patch for widening of the right ventricular outflow tract of tetralogy of Fallot.

[Possible roles of airway epithelial cells in the control of airway smooth muscle tone]

While the airway epithelium provides a diffusion barrier to the access of inhaled stimulants, it has recently been considered to have a more active physiological and pharmacological role in the regulation of the airway smooth muscle tone. The initial evidence for this comes from the fact that mechanical removal of the airway epithelium increases the in vitro responsiveness of airway smooth muscle to various spasmogens 3-5 times, although the nature of these regulatory mechanisms on the smooth muscle by the epithelium remains largely unresolved. One of the possible explanations is that the epithelium a generates factor(s) that inhibits the responsiveness of the underlying smooth muscle cells (epithelium-derived inhibitory or relaxing factor EpDIF/EpDRF). Furthermore, recent investigations revealed that airway epithelial cells also release a factor(s) that modulates the vascular smooth muscle tone, excitatory-neuroeffector transmission and resting membrane potential of the airway smooth muscle cells (epithelium-derived hyperpolarizing factor: EpDHF). This review will present and discuss the evidence indicating that the epithelium generates and releases a factor(s) that modulates smooth muscle tone, resting membrane potential of airway smooth muscle cells (EpDHF) and excitatory neuro-effector transmission in the airway.

[The effect of preclotting and collagen coating on endothelializing rate and thrombogenesity of Dacron grafts in the canine thoracic aorta]

Although high porosity knitted Dacron is generally recognized to have superior healing characteristics over woven Dacron, its porosity must be controlled at the clinical operation. This can be achieved with several materials, including geratin, insoluble collagen, albumin, and fibrin. We made atherocollagen coated graft using EX-313 as a new crosslinking agent. The purpose of this study is to compare the endothelializing rate and thrombogenesity of Dacron grafts coated by atherocollagen in the canine thoracic aorta with preclotting grafts with blood or albumin. Five groups were studied: Control group (n = 10), without preclotting; A-P group (n = 8), preclotting with albumin; B-P group (n = 5), preclotting with blood; W-C group (n = 5), atherocollagen coating with low cross-linkage; S-C group (n = 7), atherocollage coating with high cross-linkage. Thoracic aorta was replaced with 8 mm graft in length of 5.0 to 5.5 cm using temporary bypass with anthron tube. Grafts were harvested 3 months following implantation, and the endothelized surface ratio was calculated by microscopic line sampling method. Endothelized surface ratio of Control group, A-P group B-P group, W-C group and S-C group were 85%, 55%, 67%, 93% and 85%, respectively. Endothelized surface ratio of W-C group and S-C group were higher (p < 0.05) than those of A-P group, B-P group. There were thrombus in non-epithelized area. We conclude that atherocollagen coated graft had superior antithrombogenesity compared to albumin or blood preclotting graft.

Significance of hepatocellular proliferation in the development of hepatocellular carcinoma from anti-hepatitis C virus-positive cirrhotic patients

BACKGROUND

There is a hypothesis explaining the pathogenesis of carcinoma that increased proliferation of tissue cells correlates with the development of carcinoma, presumably by increased rate of random mutations and by promotion. In this study, the significance of hepatocellular proliferation in the development of human hepatocellular carcinoma (HCC) from anti-hepatitis C virus (HCV)-positive cirrhotic patients was studied.

METHODS

Twenty-eight Child A cirrhotic patients who were anti-HCV (C-100 antibody) positive were studied. At the beginning of the study, the in vitro uptake of bromodeoxyuridine (BrdU, a thymidine analogue) by hepatocytes in biopsied liver specimens was investigated as labeling indices (LIs), and they were divided into high-DNA synthetic (BrdU LI > or = 1.5%) and low-DNA synthetic (BrdU LI < 1.5%) groups. The patients were then surveyed prospectively with frequent ultrasonography (every 3 months) for the development of HCC for 3 years.

RESULTS

The mean BrdU LI plus or minus standard deviation for 14 cirrhotic patients with high-DNA synthesis activity (BrdU LI > or = 1.5%) was 2.7 +/- 0.8%, and this was significantly (P < 0.001) higher than that for 14 cirrhotic patients with low-DNA synthesis activity (BrdU LI < 1.5%, 0.5 +/- 0.3%). Nine of 14 (64.3%) of the cirrhotic patients with high-DNA synthesis activity developed HCC in the 3-year period, in contrast to only 2 of 14 (14.3%) of the cirrhotic patients with low-DNA synthesis activity P < 0.05).

Structural analysis of the functional gene and pseudogene encoding the murine granulocyte colony-stimulating-factor receptor

Granulocyte colony-stimulating factor is a cytokine which specifically regulates the production of neutrophilic granulocytes. The granulocyte colony-stimulating-factor receptor (GCSFR) is mainly expressed in neutrophils and their precursor cells. In this study, we isolated the chromosomal gene for murine GCSFR and determined its structure. Like the human GCSFR gene homolog, it consists of 17 exons. The exon-intron organization of the murine and human GCSFR-encoding genes are very similar, except that exon 14 and exon 15 in the murine gene are interrupted by a larger intron (greater than 10 kbp) than that found in the human gene (128 bp). This GCSFR-encoding functional gene (Csfgr) was localized to the distal region of murine chromosome 4 by interspecific backcross mapping. A comparison of the 5' flanking sequence of murine and human Csfgr revealed that a sequence of approximately 300 bp upstream from the cap site is highly conserved. Within this region, an 18-nucleotide element conserved in the promoter of the genes for neutrophil-specific enzymes, was found approximately 140 bp upstream from the cap site, suggesting an involvement of this element in the specific expression of GCSFR in neutrophilic granulocytes. In addition to the functional GCSFR-encoding gene, we isolated a pseudogene for GCSFR, which is flanked by a 15-bp direct repeat at the 5' and 3' ends, and lacks all introns, exons 1-3 and exons 7-8 of the functional gene. The processed pseudogene has, in its most 5' region, a sequence of approximately 200 bp that is highly related to the DNA sequence approximately 1.2 kbp upstream of the cap site of the functional gene.