[Surgical treatment of bronchial carcinoid: report of seven cases]

Seven patients with pulmonary carcinoid including three with typical carcinoid and four with atypical carcinoid were reported. There were 3 males and 4 females, with an age range of 37 to 80 years. All patients with typical carcinoid had pathological stage I. Of the patients with atypical carcinoid, one patient had stage I, two stage IIIA and one stage IIIB. All but two patients underwent lobectomy and mediastinal lymph node dissection. Bronchoplastic operation or right pneumonectomy were performed in the two patients. All but one patient underwent absolute or relative curative operation. Only one patient died on the 4th postoperative day. One patient with atypical carcinoid died of cancer recurrence 4 years after surgery. One patient died of breast cancer. One patient underwent surgery for metachronous multiple lung cancer, and he is doing well without recurrence. In conclusion, a limited operation is thought to be acceptable only in patients with typical carcinoid in a peripheral lesion without lymph node metastasis. Lobectomy and mediastinal lymph node dissection is necessary for the atypical carcinoid case.

Chromosomal assignment of a novel human gene D40

We have previously reported an identification of a novel human cellular factor, D40. Here, we report the chromosomal localization of the gene that encodes D40. Fluorescent in situ hybridization (FISH) was performed to determine the chromosomal region that D40 gene resides. The chromosomes that derived from normal adult male lymphocytes were hybridized with a mixture of cDNA probes that cover the entire coding region of D40. D40 gene mapped to the long arm of chromosome 15q14-15.

Complex formation between hepatitis C virus core protein and p21Waf1/Cip1/Sdi1

The core protein (Core) of hepatitis C virus (HCV) has been known to play an important role in hepatocarcinogenesis. By using glutathione S-transferase (GST) pull-down assay, we show here that Core formed a complex with p21Waf1/Cip1/Sdi1 (p21) cell cycle regulator. The deletion-mapping analysis revealed that a portion near the N-terminus of Core (amino acids 24-52) and a C-terminal portion of p21 (amino acids 139-164) were involved in the complex formation. The complex formation was not impaired by point mutations of p21 at residues 147, 149, and 150, which have been reported to abrogate interaction of p21 with proliferating cell nuclear antigen (PCNA), discriminating the Core-binding sequence from the PCNA-binding sequence. Due to the close vicinity of the binding sites, however, Core and PCNA competed with each other when interacting with p21. The distinct interaction between Core and p21 may provide a new aspect to the studies of HCV pathogenesis.

The role of the UL41 gene of herpes simplex virus type 1 in evasion of non-specific host defence mechanisms during primary infection

The UL41 gene product (vhs) of herpes simplex virus (HSV) is packaged in the virion, and mediates host protein synthesis shutoff at the early stage of the virus replication cycle. In order to clarify the role of vhs in virus replication and virulence, we isolated a completely UL41-deficient mutant (the VRDelta41 strain) and its revertant (the VRDelta41R strain). In the mouse encephalitis model, the replication of strain VRDelta41 was inhibited after 2 days post-infection, resulting in low virulence, by gamma-ray-sensitive cells such as lymphocytes and/or neutrophils. The result suggested that some cytokines, produced in VRDelta41-inoculated brains, activate and induce the migration of gamma-ray-sensitive cells to the infection site. Therefore, cytokines produced by HSV-1-infected human cells were screened, and potent inductions of interleukin (IL)-1beta, IL-8 and macrophage inflammatory protein-1alpha by VRDelta41 infection were observed. Moreover, the VRDelta41 strain showed 20- and 5-fold higher sensitivity to interferon-alpha and -beta compared to the wild-type strain, respectively. These results indicate that one important role of vhs in vivo is evasion from non-specific host defence mechanisms during primary infection through suppression of cytokine production in HSV-infected cells and reduction of the anti-HSV activity of interferon-alpha and -beta.

Effect of ER-27856, a novel squalene synthase inhibitor, on plasma cholesterol in rhesus monkeys: comparison with 3-hydroxy-3-methylglutaryl-coa reductase inhibitors

Squalene synthase (SQS; EC 2.5.1.21) plays an important role in the cholesterol biosynthetic pathway. We discovered ER-28448, 5-(N-[2-butenyl-3-(2-methoxyphenyl)]-N-methylamino)-1, 1-penthylidenebis(phosphonic acid) trisodium salt, as a potent and selective inhibitor of SQS. ER-28448 inhibited SQS in rat liver microsome with an IC(50) value of 3.6 nm. We also prepared ER-27856, the tripivaloyloxymethyl ester prodrug of ER-28448. Although less active than ER-28448 in a liver microsome assay, ER-27856 more potently inhibited cholesterol biosynthesis in rat hepatocytes; and ER-27856 orally inhibited de novo cholesterol biosynthesis in Sprague-Dawley rats, with an ED(50) value of 1.6 mg/kg. In HepG2 cells, ER-27856 upregulated low density lipoprotein receptor activity to 2.1 times that of control. A time-course study indicated that the inhibitory effect of ER-27856 on cholesterol biosynthesis in rats continued for up to 8 h. In a study of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (HMGRIs), atorvastatin actively suppressed cholesterol biosynthesis for 8 h, whereas the effect of pravastatin and simvastatin diminished at 4 and 8 h, respectively. In rhesus monkeys, 4 days of oral administration of ER-27856 lowered plasma total cholesterol (TCHO) more potently than did these HMGRIs. Whereas atorvastatin significantly elevated plasma alanine aminotransferase, a marker of hepatotoxicity, to 3.7 times at 100 mg/kg, ER-27856 increased the level only 1.4 times at 10 mg/kg, at which doses the hypocholesterolemic effect was equivalent. During 28 days of administration, ER-27856 reduced TCHO and non-high density lipoprotein (non-HDL) cholesterol by 72 and 95%, respectively. These results demonstrate that ER-27856 had more potent hypocholesterolemic activity and less hepatotoxic effect than HMGRIs. ER-27856 may contribute to the treatment of hypercholesterolemic patients.

Two CPT2 mutations in three Japanese patients with carnitine palmitoyltransferase II deficiency: functional analysis and association with polymorphic haplotypes and two clinical phenotypes

Carnitine palmitoyltransferase II (CPT II) deficiency manifests as two different clinical phenotypes: a muscular form and a hepatic form. We have investigated three nonconsanguineous Japanese patients with CPT II deficiency. Molecular analysis revealed two missense mutations, a glutamate (174)-to-lysine substitution (E174K) and a phenylalanine (383)-to-tyrosine substitution (F383Y) in the CPT II cDNA. Transfection experiments in COS-1 cells demonstrated that the two mutations markedly decreased the catalytic activity of mutant CPT II. Case 1 (hepatic form) was homozygous for the F383Y mutation, whereas case 3 (muscular form) was homozygous for the E174K mutation. Case 2 and her brother, who were compound heterozygotes for E174K and F383Y, exhibited the hepatic phenotype. We also identified a novel polymorphism in the CPT2 gene, a phenylalanine (352)-to-cysteine substitution (F352C), which did not alter CPT II activity in transfected cells. It was present in 21 out of 100 normal alleles in the Japanese population, but absent in Caucasian populations. Genotyping with the F352C polymorphism and the two previously reported polymorphisms, V368I and M647V, allowed normal Japanese alleles to be classified into five haplotypes. In all three families with CPT II deficiency, the E174K mutation resided only on the F1V1M1 allele, whereas the F383Y mutation was observed on the F2V2M1 allele, suggesting a single origin for each mutation.

Re-use of left internal thoracic artery for redo operation after MIDCAB

We report a case of recycling of left internal thoracic artery (LITA) in situ in reoperation of coronary artery bypass grafting. A 41-year-old male, who has poor-controlled hypercholesterolemia, was bypassed LITA to the left anterior descending artery (LAD) in minimally invasive direct coronary artery bypass (MIDCAB) manner at the other hospital. Four months later, he felt short of breath on effort. Coronary angiogram showed stenoses of the left main trunk and anastomosis site of the LITA. At redo operation, we skeletonised the LITA and reused it in situ to the LAD. Using the skeletonised method for re-harvesting LITA made the graft reach a more distal portion without tension. He is doing well at 18 months after surgery. In selected patients, recycling of the used arterial grafts can reserve other arterial grafts for redo operations in the future.

Gender-dependent effect of L-NAME on polycystic kidney disease in Han:SPRD rats

To determine whether the renal nitric oxide (NO) system has a role in the pathogenesis of polycystic kidney disease (PKD) in Han:Sprague-Dawley (SPRD) rats, the NO synthase (NOS) inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), 70 mg/L, or L-arginine, 0.5 g/L, was administered to heterozygous diseased (cy/+) and homozygous normal animals. Urine nitrate and nitrite excretion was reduced by L-NAME treatment and, in the male cy/+ rats, increased by L-arginine administration. The administration of L-NAME significantly increased blood pressure in all groups, whereas L-arginine had no effect. L-NAME and L-arginine had a modest but significant overall effect on the severity of cystic disease in male rats, reflected by relative kidney weights and cyst volume densities. This effect was gender dependent because it was not observed in female animals. The administration of L-NAME resulted in a significant increase in plasma creatinine concentration of the cy/+ rats, which was more marked in male than female animals. These observations support the recently reported gender differences in the renal NO system and a small role for NO synthesis that can be inhibited by L-NAME in the pathogenesis of PKD in Han:SPRD rats. These observations do not exclude a more important role for the endogenous renal NO production in the pathogenesis of PKD in view of a recent report of a major NOS resistant to conventional inhibitors in the rat kidney.

Thoracoscopic treatment of primary chylopericardium

The development of video-assisted thoracoscopy has changed the practice of thoracic surgery. This report describes a 20-year-old man who successfully underwent thoracoscopic thoracic duct ligation and partial pericardiectomy for primary chylopericardium. We recommend a right-sided thoracoscopic approach to the thoracic duct in the lower thoracic cavity.

Molecular and biochemical characterization of a serine proteinase predominantly expressed in the medulla oblongata and cerebellar white matter of mouse brain

A full-length cDNA clone of a serine proteinase, mouse brain serine proteinase (mBSP), was isolated from a mouse brain cDNA library. mBSP, which has been recently reported to be expressed in the hair follicles of nude mice, is most similar (88% identical) in sequence to rat myelencephalon-specific protease. The mBSP mRNA was steadily expressed in the brain of adult mice with a transient expression in the early fetal stage during development. The genomic structure of the mouse gene for mBSP was determined. The gene, which is mapped to chromosome 7B4-B5, is about 7.4 kilobases in size and contains 7 exons. Interestingly, the 5'-untranslated region of the mBSP gene was interrupted by two introns. In situ hybridization analyses revealed that mBSP is expressed in the white matter of the cerebellum, medulla oblongata, and capsula interna and capsula interna pars retrolenticularis of mouse brain. Further, mBSP was immunolocalized to the neuroglial cells in the white matter of the cerebellum. Recombinant mBSP was produced in the bacterial expression system and activated by lysyl endopeptidase digestion, and the activated enzyme was purified for characterization. The enzyme showed amidolytic activities preferentially cleaving Arg-X bonds when 4-methylcoumaryl-7-amide-containing peptide substrates were used. Typical serine proteinase inhibitors, such as diisopropyl fluorophosphates, phenylmethanesulfonyl fluoride, soybean trypsin inhibitor, aprotinin, leupeptin, antipain, and benzamidine, strongly inhibited the enzyme activity. The recombinant mBSP effectively hydrolyzed fibronectin and gelatin, but not laminin, collagens I and IV, or elastin. These results suggest that mBSP plays an important role in association with the function of the adult mouse brain.

Inhibition of A beta fibril formation and A beta-induced cytotoxicity by senile plaque-associated proteins

A beta neurotoxicity is generally believed to require A beta fibril formation. The prevention of A beta fibril formation thus seems to be a promising strategy for the treatment of AD. Recent studies have shown senile plaque-associated proteins such as laminin to have an inhibitory effect on both A beta40 and A beta42 fibril formation in vitro. In the present study, we thus investigated whether or not midkine (MK) and alpha2-macroglobulin (alpha2M), both of which are also senile plaque-associated proteins like laminin, affect A beta fibril formation and A beta-induced cytotoxicity. The present study demonstrated that both MK and alpha2M inhibit both A beta fibril formation and A beta-induced cytotoxicity in PC12 cells. The confirmation of the present results based on in vivo experiments is called for in future studies to clarify whether or not senile plaque-associated proteins such as MK and alpha2M can be a model for therapeutic agents in the treatment of AD.

Maxillary protraction and chincap appliance treatment effects and long-term changes in skeletal class III patients

The purpose of this study was to investigate the orthopedic effects of combined maxillary protraction appliance (MPA) and chincap therapy on growing Japanese girls and the posttreatment changes after growth is complete. To estimate the actual effects of treatment and posttreatment changes, we used a series of templates that had been constructed from semilongitudinal data of Japanese girls with normal occlusion. During treatment, forward movement of the maxilla with counterclockwise rotation, and backward and downward movement of the mandible with clockwise rotation and growth retardation were observed. The forward movement of the maxilla persisted until growth was complete. During the posttreatment period, the mandible maintained its improved position but showed excessive growth, which could be a rebound change. These results indicate that combined MPA and chincap treatment is effective for correcting skeletal Class III malocclusion.

Characteristics of Streptococcus species isolated from infectious skin diseases

During the period from January of 1995 to June of 1998, 27 beta-hemolytic streptococci were isolated from 25 cases of infectious skin diseases including secondary infections, impetigo, phlegmone, and paronychia. The rate of beta-hemolytic streptococci among all kinds of the isolates was found to be similar during those 4 years, ranging from 3.5% to 5.6%. Staphylococcus aureus were found to coexist with beta-hemolytic streptococci in 20 (80%) out of 25 cases. beta-hemolytic streptococci were also often associated with coagulase-negative staphylococci, gram-positive rods, or other species. Twelve cases (48%) carried beta-hemolytic streptococci predominantly. Most beta-hemolytic streptococci showed high susceptibilities to all antimicrobials tested; however S. agalactiae showed no susceptibility to gentamicin. The evaluation of characteristics of Streptococcus species is very important for selecting the right antimicrobial agents and the proper term of chemotherapy.

Carbon dioxide insufflation aids video-assisted thoracic surgery in a young child

A 3-year-old girl with pectus excavatum successfully underwent exploration using video-assisted thoracic surgery. A complete pericardial defect was identified. The lung was kept totally collapsed during the procedure using low-flow (1 L/min), low-pressure (7 mmHg) carbon dioxide insufflation. This technique is expected to be a safe adjunct to thoracoscopic procedures in infants and small children.

Diastolic potentials in verapamil-sensitive ventricular tachycardia: true potentials or bystanders of the reentry circuits?

BACKGROUND

Diastolic potentials (DP) are reported to be recorded in intracardiac electrograms during verapamil-sensitive ventricular tachycardia (VT) in which QRS complexes show complete right bundle branch block with a superior axis. The purpose of this study was to ascertain whether the DP recorded in the endocardial mapping during VT reflects the activation of the VT circuit.

METHODS AND RESULTS

The study group consisted of 16 men and 2 women. The earliest activation site (EA site) was determined and the DP was recorded in the endocardial mapping during VT. We evaluated the response of the cycle length of VT, the interval between the ventricular activation and the DP (V-DP), and the interval between the DP and the ventricular activation (DP-V) to intravenous verapamil. Radiofrequency current was delivered to the EA site, the site where the DP was recorded, and the site where the DP and the Purkinje fiber potential of the left bundle branch (LB) were simultaneously recorded. In 15 patients, the DP was recorded in the wide posterior fascicle region of the LB. After verapamil, the cycle length of VT, the V-DP, and the DP-V were prolonged from 365 +/- 53 to 490 +/- 65, 315 +/- 30 to 368 +/- 30, and 50 +/- 27 to 123 +/- 36 ms, respectively, in 6 patients. The LB was recorded in all patients and the DP was recorded preceding the LB in 12 patients. VT was successfully ablated at the site where the DP and the LB were simultaneously recorded in all these patients. Ablation at the other sites failed.

CONCLUSIONS

Radiofrequency ablation at the site where the DP was simultaneously recorded preceding the LB completely abolished the verapamil-sensitive VT. The DP recorded with the LB simultaneously might reflect the slow conduction zone activity of the reentry circuit located within the Purkinje fiber network.

Human subtilisin-like proprotein convertase, PACE4 (SPC4) gene expression is highly regulated through E-box elements in HepG2 and GH4C1 cells

PACE4 (SPC4) is a member of the mammalian subtilisin-like proprotein convertase (SPC) family, which participates in maturation of precursor proteins. PACE4 is expressed at high levels in the anterior pituitary, central nervous system, the developing olfactory bulb, heart, and liver. Recently, we determined the gene structure of human PACE4. [Tsuji et al. (1997) J. Biochem. 122, 438-452]. The 5'-flanking region of PACE4 gene contains 12 E-boxes (E1 to E12) within 1 kb upstream of the transcription initiation site. To examine the function of these E-box elements in the regulation of PACE4 expression, deletion and mutation constructs of the 5'-flanking region were ligated to the luciferase gene and analyzed for promoter activity in HepG2 and GH4C1 cells, which express PACE4 at high level. Some differences were observed in the activity of each promoter construct between HepG2 and GH4C1 cells, although the overall profiles of activity for the promoter fragment series were similar regardless of cell type. We showed that the basal promoter activity of the PACE4 gene is first determined by sequences lying between -315 and -1 bp and further regulated by positive and negative elements in the upstream region. Site-directed mutagenesis of E-boxes in these regulatory elements showed that the E10 E-box act as positive regulator, whereas an E-box cluster (E4-E9) acts as a negative regulator in both cells. E2 E-box acts as a positive regulator only in HepG2 cells. Other E-boxes (E1, E3, and E12) had no effect on the promoter activity. These results indicate that E-box elements play a critical role in controlling PACE4 expression in HepG2 and GH4C1 cells and that PACE4 expression is regulated by a mechanism distinct from that of other SPC family proteases.

Structure and localization of the mouse prolyl oligopeptidase gene

We have cloned and characterized the genomic structure of the mouse gene for prolyl oligopeptidase that is mapped to chromosome 10B2-B3. The gene is about 92 kilobases in size and contains 15 exons. All exon-intron junction sequences conform to the GT/AG rule. Comparison with the presumed domain structures of the mouse prolyl oligopeptidase indicates that the propeller domain of the enzyme is encoded by exons 3-10, whereas the catalytic domain is encoded by exons 1-3 and 10-15. The catalytic triad residues are encoded by two exons (Ser(554) on exon 13 and His(680) and Asp(642) on exon 15). The 5'-flanking region of the mouse prolyl oligopeptidase gene has structural features found in housekeeping gene promoters, including a GC-rich segment and an absence of TATA and CAAT boxes. A primer extension assay showed the presence of multiple sites for the initiation of transcription. Transient transfection analysis demonstrated that the 5'-flanking region of the gene can direct efficient expression in COS1 cells. Deletion studies revealed that the downstream 125-base pair sequence of the region is required for promoter activity in the cells.

Enhanced GRK5 expression in the hearts of cardiomyopathic hamsters, J2N-k

GTP binding protein-coupled receptor kinase 5 (GRK5) cDNA was cloned from the hearts of Syrian hamsters. The hamster GRK5 cDNA contained 1770 nucleotides encoding 590 amino acids, and the nucleotide sequence had 89.6% homology to the human homologue. An inbred cardiomyopathic hamster strain, J2N-k, was used to investigate the alteration of GRK5 mRNA expression in the setting of congestive heart failure. M-mode echocardiography revealed significant dilatation of the left ventricle and a decrease of left ventricular contractility in 20-week-old J2N-k hamsters compared with age-matched control hamsters, J2N-n. Semi-quantitative RT-PCR showed that GRK5 mRNA expression in the hearts of J2N-k was significantly higher than in those of J2N-n (J2N-k 60.3 +/- 13.3, J2N-n 25.8 +/- 17.2 arbitrary units, p < 0.005, n = 6 in each group). These results suggest that an enhanced GRK5 expression might play a role in the reduced responsiveness to catecholamines in failing hearts via beta-adrenergic receptor phosphorylation.

Insufficient resistance of trehalose-6,6-dimycolate-treated T-cell receptor delta gene mutant (TCR delta-/-) mice against influenza virus infection

Normal mice inoculated intravenously with 50 microg trehalose-6,6'-dimycolate, a glycolipid component of the cell wall of Mycobacterium, in an oil-in-water emulsion (TDM emulsion) acquired a high resistance to intranasal lethal infection of an influenza virus. In contrast, TDM emulsion-treated T-cell receptor delta gene mutant (TCR delta-/-) mice acquired insufficient resistance against the lethal influenza virus infection. The patterns of insufficient resistance were identical to the results obtained previously with mice which were depleted of T-lymphocytes bearing gammadelta T-cell receptors (gammadelta T-cells) by in vivo administration of anti-gammadelta T-cell receptor monoclonal antibody (Hoq et al, J. Gen. Virol. 78: 1597-1603, 1997). These results strongly suggest that the gammadelta T-cells play an important non-specific role in resistance against influenza virus infection.

Pilot study of gas chromatographic-mass spectrometric screening of newborn urine for inborn errors of metabolism after treatment with urease

Gas chromatographic-mass spectrometric (GC-MS) techniques for urinary organic acid profiling have been applied to high-risk screening for a wide range of diseases, mainly for inborn errors of metabolism (IEM), rather than to low-risk screening or mass screening. Using a simplified procedure with urease-pretreatment and the GC-MS technique, which allows simultaneous determination of organic acids, amino acids, sugars and sugar acids, we performed a pilot study of the application of this procedure to neonatal urine screening for 22 IEM. Out of 16,246 newborns screened, 11 cases of metabolic disorders were chemically diagnosed: two each of methylmalonic aciduria and glyceroluria, four of cystinuria, and one each of Hartnup disease, citrullinemia and alpha-aminoadipic aciduria/alpha-ketoadipic aciduria. The incidence of IEM was thus one per 1477, which was higher than the one per 3000 obtained in the USA in a study targeting amino acids and acylcarnitines in newborn blood spots by tandem mass spectrometry. Also, 227 cases were found to have transient metabolic abnormalities: 108 cases with neonatal tyrosinuria, 99 cases with neonatal galactosuria, and 20 cases with other transient metabolic disorders. Two hundred and thirty-eight cases out of 16,246 neonates (approximately 1/68) were thus diagnosed using this procedure as having either persistent or transient metabolic abnormalities.

Elimination of CO2 in patients with carbonic anhydrase II deficiency, with studies of respiratory function at rest

We evaluated the elimination of CO2 in three Japanese adults with carbonic anhydrase II (CA II) deficiency, as compared with that in 10 healthy volunteers. The patients had no signs of respiratory distress. Heart rate, body temperature, ventilation volume, respiratory rate and (a-ET) PCO2 were found to be higher and PaCO2 tended to be higher in the patients than those in the volunteers, while forced vital capacity (FVC), forced expiratory volume in 1s (FEV1), tidal volume, end-tidal PCO2 (PETCO2), pH and HCO3- in arterial blood were lower in the patients. All three patients had non-anion-gap metabolic acidosis, due to renal losses of bicarbonate, but with virtually no compensatory reduction in PaCO2. However, the high VE and PaO2 suggested that respiratory compensation for this metabolic acidosis was occurring, the elimination of CO2 was possibly facilitated by the presence of other carbonic anhydrase isoenzymes in the pulmonary capillaries. Thus, CA II deficiency causes mild to moderate impairments in CO2 elimination.

[Bacterial mutation in high magnetic fields and radiofrequency radiation]

Epidemiological studies recently have indicated that magnetic fields and radiofrequency (RF) radiation have an adverse influence on the living body. The purpose of this study was to examine the safety of magnetic resonance imaging (MRI) by observing whether bacterial mutation occurs in an approximate MRI environment. We employed a GX-270 FT-NMR unit (JEOL, Ltd.) with a magnetic field strength of 6.3 Tesla. The Salmonella typhimurium tester strains used in the AMES test were exposed, and the incidence of point and frameshift mutations was evaluated. TA98 and TA7001-7006 mixed strains were used to detect frameshift and point mutations, respectively. Tester strains were exposed to the 6.3 Tesla magnetic field with RF radiation (90 degrees and 180 degrees refocusing pulses were repeated using the hydrogen Lamor frequency at 2-second intervals) for 15, 30, 45, and 60 minutes. After each exposure, the rate of revertant mutation was counted. The rates of revertant mutation in mixed strains and the TA98 strain were not statistically significant. Therefore, it was concluded that bacterial mutation is not increased by RF radiation under a 6.3 Tesla magnetic field.