Cystic acoustic neurinomas: studies of 14 cases

Cystic acoustic neurinomas (ANs) are less frequent and are different from solid ANs in clinical and radiological features. We had 14 cystic ANs (13.5% of 104 cases) in the last 17 years. Computerized tomographic or magnetic resonance images allowed for the classification of these cystic ANs into three types: Type A being large single cysts with a thin tumourous wall (7 cases); type B single cysts with a thick tumourous wall (3 cases); type C multicystic (4 cases). Half of the cystic ANs were not accompanied by enlargement of the internal auditory canal, despite the largeness of the cysts. The mean size of the tumours was 29 mm in diameter. Type A cysts had a shorter clinical history than types B and C. One patient had intact hearing. In five cases, an atypical initial symptom such as facial pain, dysgeusia, facial palsy, unsteadiness or vertigo presented. The trigeminal nerve was involved in 12 cases, the facial nerve in nine. The characteristic features of cystic ANs are largeness of the tumour, a short clinical history, an atypical initial symptom, facial nerve involvement, and/or no enlargement of the internal auditory canal. In addition, the histological features are a lobular growth pattern, high nuclear atypia, and numerous macro phages.

[Usefulness and limitation of serum tumor markers in diagnosis of lung cancer]

In the clinical practice of lung cancer, serum tumor markers are important laboratory tests and their use is wide spread. Among the various markers for lung cancer, the usefulness of CEA, SLX, SCC and NSE has been firmly established. These markers cannot be used routinely to screen for lung cancer but may be used as complementary tools for diagnosing the tumor. Elevated levels of these markers also appear to be useful for monitoring the response to therapy and tumor progression. CYFRA21-1 and ProGRP, new tumor markers with relatively high sensitivity and specificity to lung cancer, were recently developed. These tumor markers may be useful tools for early detection of lung cancer.

Behavior of the cell cycle-associated proteins in an unusual G0-arrestable cancer cell line

An adenocarcinoma cell line which has the ability to arrest in G0 phase under exhausted culture conditions was established. Using the cell line, we investigated the expression of cell cycle-associated proteins including cdc2, cdk2, cyclin A, cyclin Dl, and Rb during entry into or withdrawal from the cell cycle. MAP kinase expression was also investigated as one of the most downstream proteins of the signal transduction of growth factors. The cells in the quiescent state did not express cdc2. In contrast, cdk2 was expressed weakly, and cyclin A and cyclin D1 were strongly expressed in the quiescent cells. The expression of cdk2 and cyclin D1 in the quiescent cells was reduced after stimulation by renewal of the medium and then increased, accompanied by Rb phosphorylation and cdc2 expression around the G1/S transition. Cdc2 and the hyperphosphorylated form of Rb disappeared as the cells became quiescent. MAP kinase expression was unchanged throughout all the phases analyzed. The results indicate that down-regulation of neither cdk2, cyclin A, cyclin D1, nor MAP kinase is necessary to arrest cells in G0, but that only Rb dephosphorylation and down-regulation of cdc2 are accompanied by an arrest of cell proliferation in G0 in the cell line.

Possible roles of tumor-associated carbohydrate antigens

Recent progress in the studies on the roles of carbohydrates has brought about critical discoveries, which allow us to have working hypotheses for understanding the roles of tumor-associated carbohydrate antigens. In this report, I focus my description on three different aspects of this progress. I discuss: (a) the immunological response to oligosaccharides aberrantly expressed under pathological conditions; (b) possible roles of carbohydrate-dependent cell adhesion during tumor metastasis; and (c) the roles of carbohydrates in modulating the functions of proteins that attach those carbohydrates. These three areas in the roles of carbohydrates will likely be the target for continuous research efforts to reveal the roles of tumor-associated carbohydrates.

Phospholipid composition dependence of Ca2+-dependent phospholipid binding to the C2A domain of synaptotagmin IV

Synaptotagmins I and II are Ca2+- and phospholipid-binding proteins of synaptic vesicles that may function as Ca2+ receptors for neurotransmitter release via their first C2 domains. Herein, we describe the phospholipid binding properties of C2A domains of multiple synaptotagmins (II-VI). We demonstrate that all synaptotagmins can bind negatively charged phospholipids (phosphatidylserine (PS) and phosphatidylinositol (PI)) in a Ca2+-dependent manner, although it was previously reported that synaptotagmins IV and VI do not bind phospholipids. The Ca2+-dependent interaction of the C2A domain of synaptotagmin IV with PS was found to have two components with EC50 values of approximately 5 and 120 microM free Ca2+ and exhibited positive cooperativity (Hill coefficient of approximately 2 for both components). This value is lower than that of the C2A domain of synaptotagmin II (Hill coefficient of approximately 3). All other isoforms bound PS with high affinity (EC50 of 0.3-1 microM free Ca2+; Hill coefficient of 3-3.5). In addition, the C2A domain of synaptotagmin IV cannot bind liposomes consisting of PS (or PI) and phosphatidylcholine, PC (or phosphatidylethanolamine, PE) (1:1, w/w), indicating that the binding to negatively charged phospholipids is inhibited by the presence of PC or PE. In contrast, other isoforms bound all of the liposomes, which include either PS or PI, in a Ca2+-dependent manner. Mutational analysis indicated that this phospholipid composition-dependent Ca2+ binding of synaptotagmin IV results in the substitution of Asp for Ser at position 244. The cytoplasmic domain of synaptotagmin IV also shows this unique phospholipid binding. However, it binds PS with a positive cooperativity and an affinity similar to those of the C2A domains of other isoforms. Our results suggest that synaptotagmin IV is also a potential Ca2+ sensor for neurotransmitter release.

Levels of recombinant human granulocyte colony-stimulating factor in serum are inversely correlated with circulating neutrophil counts

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is effective in countering chemotherapy-induced neutropenia. However, serum rhG-CSF levels cannot be maintained throughout the course of rhG-CSF therapy. The drop in serum rhG-CSF levels may vary with the duration of rhG-CSF administration or with the circulating neutrophil counts. We investigated the relationship between serum G-CSF levels and circulating neutrophil counts and the pharmacokinetics of rhG-CSF for patients with lung cancer who had been treated with myelosuppressive chemotherapy and then with subcutaneous rhG-CSF (lenograstim, 2 micrograms per kg of body weight per day). Twelve patients were randomly assigned to four groups with different rhG-CSF therapy schedules. Serum G-CSF levels were measured by an enzyme immunoassay method. Serum G-CSF levels during the rhG-CSF therapy greatly exceeded endogenous G-CSF levels and were mainly due to the presence of exogenous rhG-CSF rather than increased levels of endogenous G-CSF. Despite the duration of rhG-CSF administration, serum G-CSF levels during rhG-CSF therapy were inversely correlated with circulating neutrophil counts (r2 = 0.73, P < 0.0001). The value for the area under the concentration-time curve of rhG-CSF on the day of neutrophilia was lower than that on the day of neutropenia (P < 0.05). Our results suggest that the fall in serum G-CSF levels during rhG-CSF therapy may result from increased clearance and/or decreased absorption of rhG-CSF, two processes related to circulating neutrophil counts.

Two deficiency cases of disputed paternity: sibling or half-sibling?

We report briefly the results of DNA analysis in two cases of disputed paternity where the alleged father and the mother were dead and only the children were available. In one case, half-sibship was established by minisatellite typing with a multi-locus probe and microsatellite FGA typing. In the other case, Y27H39 typing revealed that the fathers of the two male children were different. DNA polymorphisms, especially at microsatellite loci, provide useful information to solve such paternity cases.

Event-related potential correlates of functional hearing loss: reduced P3 amplitude with preserved N1 and N2 components in a unilateral case

A female patient exhibiting functional hearing loss in her left ear demonstrated reduced amplitude of P3 component in event-related potentials (ERP) to left monaural stimulation, with preserved N1 and N2 components to stimulation of either ear. This result suggested that stimuli in the affected ear were conducted successfully up to the auditory cortex but that further processing in higher brain regions was 'repressed'. Event-related potential examination for such hysterical disorders could be useful in clarifying their brain mechanism and offer a useful diagnostic clue to its nature.

Microsatellite typing in a paternity case against a deceased man whose two brothers were available for testing

To resolve a deficiency case of disputed paternity, we examined the mother, child, and two sibs of the deceased alleged father. In all of the 11 conventional marker systems and three microsatellite systems (ACTBP2, FGA, and D11S488) applied, the child and the paternal sibs had alleles is common. We deduced first the possible ACTBP2 genotypes of the deceased parents of the two sibs from their test results. Next, from all the combinations of the deduced genotypes, we estimated the frequencies of the possible genotypes of the alleged father and, with Bayes' theorem, calculated the probabilities of the alleged father having the genotypes compatible with paternity. Using these probabilities, we worked out the probability of the child's genotype resulting from the mating of the mother with the alleged father. Meanwhile, we calculated the probability of the child's genotype being expected of the mating of the mother with an unrelated random man. Finally, applying Bayes' theorem again, we obtained a probability of paternity of 0.992 for the ACTBP2 locus alone. Inclusion of the FGA locus in the probability calculations brought the overall probability of paternity to 0.998. The present study demonstrates that testing for hypervariable microsatellite loci greatly facilitates the solution of a deficiency case that would be difficult or time-consuming to solve by conventional marker typing.

Estimation of polyunsaturated fatty acid content in lipids of aquatic organisms using thin-layer chromatography on a plain silica gel plate

We have designed a rapid method for the separation of polyunsaturated fatty acids (PUFA, > or = trienes) from non-PUFA, and for estimation of total amounts of PUFA in lipids of aquatic organisms. Lipids from thirty-one species, including marine and fresh water fishes, shell fishes, marine algae, and other aquatic animals, and from terrestrial organisms, were transesterified with sodium methoxide in methanol. The resulting fatty acid methyl esters were separated by thin-layer chromatography on commercially available plain silica gel plates with a developing solvent of n-hexane/ethyl ether/acetic acid (95:5:1, by vol). All of the methyl esters from aquatic organisms tested separated into two spots, whereas those from terrestrial sources, except for linseed oil, showed a single unresolved spot. The upper and lower spots were scraped separately from the plate, and their fatty acid compositions were determined by gas-liquid chromatography. The lower spot was composed of PUFA having more than two double bonds, whereas components of the upper spot were saturated, monoenoic, and the greater part of the dienoic fatty acids. When the spots on the silica gel plate were stained with Coomassie brilliant blue, the amounts of PUFA in aquatic organisms could be estimated satisfactorily using a scanning densitometer.

The influence of blood gas changes on hyperthermia-induced seizures in developing rats

Fever induces seizures in infants with febrile convulsions or epilepsy. Hyperpnea induced by fever may contribute to the induction of these seizures. In order to examine this possibility, we evaluated the effect of changes in arterial blood gas tension on hyperthermia-induced seizures in developing rats. Electrical seizure discharges were induced by application of infra-red rays on the skull of rats under mechanical ventilation with different respiratory conditions. There was positive correlation between pCO(2) and the seizure threshold (ST) defined as a latency from the start of hyperthermia to the occurrence of seizures: ST (seconds, s) = 2.36 pCO(2) + 0.05 (R(2) = 0.80, P < 0.001). Seizure duration (SD) was longer at lower pCO(2) level: 18 (6-33) (median, range) s at pCO(2) ranging from 23 to 26 mmHg vs. 0 (0-7) s at pCO(2) ranging from 35 to 57 mmHg (P < 0.01). Hypoxia significantly increased ST: 84 (61-100) s at P0(2) ranging from 53 to 76 mmHg vs. 60 (51-72) s at P0(2) ranging from 87 to 131 mmHg (P < 0.01). Hyperoxia prolonged SD: 27 (10-30) s at P02 ranging from 100 to 170 mmHg vs. 9 (0-23) at P0(2) ranging from 53 to 93 mmHg (P < 0.02). Hypocarbia caused by fever-induced hyperpnea probably contributes to the generation of fever-induced seizures.

Optimal schedule for administering granulocyte colony-stimulating factor in chemotherapy-induced neutropenia in non-small-cell lung cancer

A prospective randomized study was conducted to determine the optimal schedule of rhG-CSF (recombinant human granulocyte colony-stimulating factor). A group of 33 lung cancer patients treated with MVP therapy (mitomycin, vindesine, and cisplatin) were randomly assigned to three groups: an early prophylaxis group in which rhG-CSF was initiated on day 2 of the MVP cycle; a late prophylaxis group in which rhG-CSF was initiated on day 8; and a therapeutic group in which rhG-CFS was initiated after the onset of neutropenia. Ten patients who had received MVP therapy without rhG-CSF were also analyzed as a no-support group. The incidence of neutropenia was 80% (16/20 courses) in the early prophylaxis group, 44% (8/18) in the late prophylaxis group, 94% (17/18) in the therapeutic group, and 94% (16/17) in the no-support group. The incidence of neutropenia in the late prophylaxis group was less than in the early prophylaxis group (P<0.05), the therapeutic group (P<0.01), and the no-support group (P<0.01). The late prophylactic rhG-CSF schedule was therefore more effective in countering neutropenia than either the early prophylactic or therapeutic schedule.

Sequential detection of tumor cells in the peripheral blood and bone marrow of patients with stage IV neuroblastoma by the reverse transcription-polymerase chain reaction for tyrosine hydroxylase mRNA

BACKGROUND

The aim of this study was to evaluate the changes of tumor cell contamination in bone marrow (BM) and peripheral blood (PB) during the clinical course of patients with advanced neuroblastoma by detecting tyrosine hydroxylase (TH) mRNA to clarify the appropriate source and time for harvesting hematopoietic stem cells for transplantation.

METHODS

A total of 15 patients with Stage IV neuroblastoma were studied. All 15 patients had peripheral blood stem cell (PBSC) samples and BM samples examined for TH mRNA by using the reverse transcription-polymerase chain reaction (RT-PCR) at the time of harvest. Nine of the 15 patients, also had BM and PB samples examined sequentially.

RESULTS

Comparing the 45 paired samples concurrently drawn, 16 of 28 BM samples (57.1%) and 4 of 28 PB samples (14.2%) obtained during complete remission (CR) were positive for TH mRNA (P < 0.01), whereas 17 of 17 BM samples (100%) and 14 of 17 PB samples (82.3%) obtained before CR was achieved were positive (not significant). The incidence of TH mRNA positivity was significantly lower in the samples obtained during CR than those obtained before CR was achieved (P < 0.0001 for PB samples, P < 0.01 for BM samples). At the time of PBSC harvesting, the incidence of TH mRNA positivity was lower in PBSC samples (3 of 15, 20%) than in BM samples obtained concurrently (10 of 15, 66.7%; P < 0.03).

CONCLUSIONS

These findings show that there is a substantial risk of tumor cell contamination in harvested PBSCs, although its incidence was lower than that in BM samples. We recommend that PBSCs would be better harvested during remission and should be examined for tumor contamination before use as a stem cell source.

Lateral suprasylvian visual cortex is activated earlier than or synchronously with primary visual cortex in the cat

To explore functional connectivity between area 17 and posteromedial lateral suprasylvian (PMLS) area of the cat cerebral cortex, we carried out cross-correlation analysis of spike trains of neurons recorded simultaneously from both areas of anesthetized, paralyzed cat. Most of correlated pairs had peaks which indicate that PMLS cells were activated earlier than or simultaneously with their partners in area 17, suggesting that 'backward' as well as synchronous activation operates between these cortical areas.

Chronic bronchial foreign body mimicking peripheral lung tumor

We describe a case with chronic bronchial foreign body presenting with recurrent hemoptysis mimicking a peripheral lung tumor, and the outcome of surgical resection. A 61-year-old female with recurrent hemoptysis had a peripheral nodule in the right lower lobe. A right bronchial arteriogram showed dilatation and hypervascularity in the nodule. Surgical removal of the nodule contained a small branch of a white cedar. Chronic bronchial foreign body, while rare in adults, should be considered in the differential diagnosis of peripheral lung tumors associated with recurrent hemoptysis.

Association of Trp64Arg mutation of the beta3-adrenergic-receptor with NIDDM and body weight gain

A possible pathogenic mutation in the beta 3-adrenergic-receptor gene (Trp64Arg) has been reported to be associated with an earlier age of onset of non-insulin-dependent diabetes mellitus (NIDDM) and clinical features of the insulin resistance syndrome in Pima Indian, Finnish and French subjects. Since marked heterogeneity has been reported in the association of mutations of candidate genes with NIDDM between Japanese and other ethnic groups, we investigated the association of Trp64Arg with NIDDM in Japanese subjects. The allele frequency of the mutation (Arg) was slightly, but not significantly, higher in NIDDM than in control subjects (70 out of 342 alleles [20.5%] vs 40 out of 248 [16.1%], respectively, p > 0.2). When our data were combined with those of Pima Indian and Finnish subjects, however, the Arg/Arg genotype was significantly associated with NIDDM as compared with the other two genotypes (p < 0.005, relative risk [RR] 2.13, 95% confidence interval [CI] 1.28-3.55). The Arg allele was also associated with NIDDM (p < 0.05, RR 1.27, 95% CI 1.06-1.52). Japanese subjects homozygous for the mutation had a significantly higher body mass index (mean +/- SD: 25.5 +/- 3.9 kg/m2) than heterozygotes (22.6 +/- 4.1, p < 0.05) and normal homozygotes (22.8 +/- 3.8, p < 0.05). NIDDM patients homozygous for the mutation tended to have an earlier age of onset of NIDDM than those with other genotypes. These data suggest that the Trp64Arg mutation not only contributes to weight gain and age-at-onset of NIDDM but is also associated with susceptibility to NIDDM.

Serum levels of cytokines in patients with untreated primary lung cancer

To evaluate the relationships between serum endogenous cytokine levels and their clinical implications in cancer patients, we measured the serum levels of endogenous granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), macrophage colony-stimulating factor (M-CSF), and interleukin 6 (IL-6) in patients with untreated primary lung cancer. The serum G-CSF level was measured using a chemiluminescent ELISA, and the other cytokine levels were measured using ELISA. Fifty healthy adults and 183 patients with primary lung cancer were studied. The mean M-CSF level in the lung cancer patients (1106.4 units/ml) was significantly higher than that in the healthy adults (836 units/ml, P = 0.0001). In patients with large cell carcinoma, endogenous G-CSF, M-CSF, and IL-6 levels were significantly higher than those in patients with carcinomas of other cell types (P < 0.05). Univariate analysis showed that survival of 159 non-small cell lung cancer patients with high (more than cutoff level) G-CSF, M-CSF, and IL-6 levels was significantly poorer than that of patients with low levels (Wilcoxon's test, P = 0.018, P < 0. 0001, and P < 0.0001, respectively). Survival of patients with high levels of two or more cytokines was poorer than that of those with high levels of one cytokine or normal cytokine levels (P < 0.0001). Multivariate analysis using Cox's proportional hazards model showed that high M-CSF and C-reactive protein levels correlated significantly with poor survival (P = 0.037 and 0.037, respectively). Our preliminary data suggest that high M-CSF levels in non-small cell lung cancer may be of poor prognostic value.

Expression cloning of a human GT3 synthase. GD3 AND GT3 are synthesized by a single enzyme

Gangliosides of the C series such as GT3 are polysialylated glycosphingolipids whose synthesis is developmentally regulated. Here we report the expression cDNA cloning and characterization of GT3 synthase that adds the second alpha-2,8-sialic acid to GD3, NeuNAcalpha2-->8NeuNAcalpha2-->3Galbeta1-->4Glc-->Cer, thus forming GT3, NeuNAcalpha2-->8NeuNAcalpha2-->8NeuNAc alpha2-->3Galbeta1--> 4Glc-->Cer. Unexpectedly, the cloned cDNA was found to be identical to the cDNA that encodes GD3 synthase. The newly identified enzyme was therefore named GD3/GT3 synthase (GD3/GT3ST). GD3/GT3ST synthesized GT3 most efficiently when GM3, NeuNAcalpha2-->3Galbeta1-->4Glc-->Cer, was incubated as an acceptor, indicating that GD3/GT3ST is a polysialyltransferase that can transfer more than one sialic acid residue via alpha-2,8 linkage to gangliosides. Moreover, a longer period of incubation of GD3 with GD3/GT3ST produced a significant amount of GT3 and higher polysialogangliosides. Among various cell lines expressing GD3/GT3ST, higher polysialogangliosides including GT3 were detected only in cell lines where the amount of GD3/GT3 mRNA is sufficiently high. The expression of GD3/GT3ST mRNA among human tissues is highly restricted to fetal and adult brains. The GD3/GT3ST gene was found to be located at chromosome 12, region p12. Taken together, these results indicate that C series polysialogangliosides are synthesized by a ganglioside-specific polysialyltransferase, GD3/GT3ST, that is specifically expressed in neural tissues.

Synergism between cisplatin and topoisomerase I inhibitors, NB-506 and SN-38, in human small cell lung cancer cells

Topoisomerase I-targeting anticancer agents such as 7-ethyl-10-[4-(1-piperidyl)-1-piperidyl]carbonyloxy-camptothecin (CPT-11) and 6-N-formylamino-12,13-dihydro-1,11-dihydroxy-13-(beta-D- glucopyranosyl)-5H-indolo[2,3-a]pyrrolo[3,4-c]carbazole-5,7(6H)-di one (NB-506) have been developed and show strong antitumor activity against various cancers. We examined the interaction of these drugs and cisplatin (CDDP), and biochemical mechanisms of synergism between them. Interaction of drugs in human small cell lung cancer cells, SBC-3, was analyzed using the isobologram method. Combinations of CDDP with NB-506, CPT-11, and an active metabolite of CPT-11, 7-ethyl-10-hydroxy-CPT (SN-38), showed synergistic effects. Formation of DNA interstrand cross-links (ICLs) on the cells was analyzed using an alkaline elution assay and increased ICLs were observed by simultaneous exposure to CDDP (1.5 microM) and NB-506 (10 nM) compared with that in response to CDDP alone. DNA repair after ICL formation induced by 3-h exposure to CDDP (1.5 microM) was reduced by NB-506 (10 nM) exposure. On the other hand, a higher concentration of CDDP (150 microM) enhanced the topoisomerase I inhibitory activity of NB-506 and SN-38 determined by relaxation of supercoiled Escherichia coli DNA. These biological interactions might result in synergistic interactions between CDDP and NB-506 or SN-38. Topoisomerase I inhibitors and CDDP may be a key regimen for cancer chemotherapy and merit further examination.

Three-dimensional structures of free form and two substrate complexes of an extradiol ring-cleavage type dioxygenase, the BphC enzyme from Pseudomonas sp. strain KKS102

The crystal structure of an enzyme having polychlorinated-biphenyl degrading activity, the BphC enzyme from Pseudomonas sp. strain KKS102, has been solved as a free form at 1.8 A resolution. This is the first three-dimensional structure among the extradiol-type dioxygenases. Based on 34,387 reflections (10.0 to 1.8 A, completeness 87.8%), a current R-factor of 20.4% (with a free R-factor of 24.3%) was obtained with a model obeying standard geometry within 0.011 A in bond lengths and 1.91 degrees in bond angles. The BphC enzyme is a homo-octamer and each subunit is composed of two domains: Domain 1 (N-terminal part) and Domain 2 (C-terminal part). Each domain contains two repetitions of a novel folding motif (the "beta alpha beta beta beta" motif) each consisting of ca 55 amino acid residues. A single Fe ion in the active site coordinates the side-chains of three amino acid residues (His145, His209 and Glu260) and two solvent molecules. The coordination geometry is that of a square pyramid. In addition to the free form of the BphC enzyme, we have solved two three-dimensional structures of the BphC enzyme complexed with its substrates, 2,3-dihydroxybiphenyl (2,3-DHBP) or 3-methylcatechol (3-MCT). These substrates were found intact in the active site probably because of the oxidation of the Fe ion into ferric form (as judged by EPR spectra) in the present crystals. In both of the two substrate complexes, the two hydroxyl groups of the substrate, together with the three enzymatic side-chain ligands, were found to form a penta-coordinated system around the Fe ion roughly arranged in a trigonal bipyramidal configuration. The active site structures appear to be essentially consistent with the reaction mechanism proposed so far.