[Two clinical case of spontaneous hemopneumothorax caused by aberrant vessel]

Spontaneous hemopneumothorax is a rare disease and intrathoracic bleeding reportedly occurs in the detached region of adhesive parietal pleura, aberrant vessel and cystic wall. We experienced two cases of bleeding most likely from the aberrant vessel. One patient was a 25-year-old male who had severe chest pain with dyspnea for four days. Chest X-ray revealed left pneumothorax and mediastinal shift to the right. Approximately 1500 ml of blood was aspirated from the left thoracic cavity. Since bleeding continued, emergency thoracotomy was performed. A restiform structure was noted in the bulla at the apex of the lung and the stump of the structure was considered as the source of bleeding. The other patient was a 29-year-old male who underwent emergency operation 16 hours after the massive bleeding amounting to 1800 ml. At the thoracotomy, a ruptured bulla at the apex of the collapsed lung with restiform structure was encountered. The bleeding point in the stump of the structure was ligated and the ruptured bulla was resected. In the histological study of these patients, an aberrant blood vessel was revealed in the restiform structure, which suggests the etiology of the bleeding. Their postoperative course was uneventful and had no symptom at the discharge. In the management of spontaneous hemopneumothorax, early thoracotomy should be the first consideration taking into account the massive bleeding from the aberrant vessel as in the cases.

Cloning and functional expression of a novel glucuronyltransferase involved in the biosynthesis of the carbohydrate epitope HNK-1

The HNK-1 carbohydrate epitope is characteristically expressed on a series of cell adhesion molecules and also on some glycolipids in the nervous system over a wide range of species from insect to mammal. The HNK-1 epitope is involved in cell-cell and/or cell-substrate interaction and recognition during the development of the nervous system. In this study, we isolated a novel glucuronyltransferase from rat brain, which is a key enzyme of the biosynthesis of the HNK-1 epitope on glycoproteins. Based on the partial amino acid sequences, we isolated cDNA encoding the glucuronyltransferase. The primary structure deduced from the cDNA sequence predicted a type II transmembrane protein with 347 amino acids and had no detectable similarity with any other proteins of known functions, including glucuronyltransferases of the liver and olfactory epithelium. Expression of a soluble recombinant form of the enzyme in COS-1 cells produced an active glucuronyltransferase. The selective expression of the glucuronyltransferase gene in the nervous system was consistent with the almost exclusive localization of the HNK-1 epitope in the nervous system. Transfection of the glucuronyltransferase cDNA into COS-1 cells induced not only expression of the HNK-1 epitope on the cell surface but also marked morphological changes of the cells, suggesting that the HNK-1 epitope associates with the cell-substratum interaction.

Studies on tumor-promoting activity of polyethylene: inhibitory activity of metabolic cooperation on polyethylene surfaces is markedly decreased by surface modification with collagen but not with RGDS peptide

Tumor promotion activity of polyethylene (PE) was estimated in terms of the inhibitory potentials on the gap-junctional intercellular communication using the metabolic cooperation assay. The gap-junctional intercellular communication of test cells was inhibited on the PE film, but this inhibitory activity was markedly decreased when the surface of the PE film was immobilized with collagen. These results suggest that the in vivo tumor promotion activity of the untreated PE may be stronger than that of collagen-immobilized PE. On the other hand, surface modification with RGDS peptide, which is well known as the sequence of cell attachment domain in extracellular matrix proteins, did not reduce the promotion activity of PE film. In addition, neither modification with bovine serum albumin nor RGES peptide reduced the activity of PE film. These findings suggest that reduction of the inhibitory activity on gap-junctional intercellular communication by collagen immobilization is not simply due to improved cell adherence via the RGDS sequence but to some cell-cell recognition via collagen molecules essential for the gap-junctional intercellular communication.

Up-regulation of the brain and Purkinje-cell forms of dystrophin transcripts, in Becker muscular dystrophy

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Genetic mapping using microcell-mediated chromosome transfer suggests a locus for Nijmegen breakage syndrome at chromosome 8q21-24

Nijmegen breakage syndrome (NBS) is an autosomal recessive disorder characterized by microcephaly, short stature, immunodeficiency, and a high incidence of cancer. Cultured cells from NBS show chromosome instability, an increased sensitivity to radiation-induced cell killing, and an abnormal cell-cycle regulation after irradiation. Hitherto, patients with NBS have been divided into the two complementation groups V1 and V2, on the basis of restoration of radioresistant DNA synthesis, suggesting that each group arises from a different gene. However, the presence of genetic heterogeneity in NBS has been considered to be controversial. To localize the NBS gene, we have performed functional complementation assays using somatic cell fusion between NBS-V1 and NBS-V2 cells, on the basis of hyper-radiosensitivity, and then have performed a genomewide search for the NBS locus, using microcell-mediated chromosome transfer followed by complementation assays based on radiosensitivity. We found that radiation resistance was not restored in the fused NBS-V1 and NBS-V2 cells and that only human chromosome 8 complements the sensitivity to ionizing radiation, in NBS cell lines. In complementation assays performed after the transfer of a reduced chromosome, merely the long arm of chromosome 8 was sufficient for restoring the defect. Our results strongly suggest that NBS is a homogeneous disorder and that the gene for NBS is located at 8q21-24.

Identification of motor and sensory brain activities during unilateral finger movement: spatiotemporal source analysis of movement-associated magnetic fields

We investigated the movement-related cortical fields (MRCFs) recorded by magnetoencephalography (MEG) to identify the motor and sensory brain activities at the instant of the unilateral finger movement using six normal subjects. We focused our investigation on the source analysis of the events tightly linked to movement onset, and we used brain electric source analysis (BESA) to model the sources generating MRCFs during the interval from 200 ms before to 150 ms after the movement onset. Four sources provided satisfactory solutions for MRCF activities in this interval. Sources 1 and 2, which were located in the pre-central regions in the hemisphere contralateral and ipsilateral to the moved finger, respectively, generated the readiness fields (RF), but source 1 was predominant just before movement onset. The motor field (MF), the peak of which was just after movement onset, was mainly generated by source 1. Sources 3 and 4 were located in the post-central regions in the hemisphere contralateral and ipsilateral to the moved finger, respectively. The first motor evoked field (MEF-I), the peak of which was about 80 ms after the movement, was mainly generated by source 3, but with the participation of sources 1, 2 and 4. The results indicated that the activities of both pre -and post-central regions in bilateral hemispheres were related to voluntary movements, although the predominant areas varied over time. This is the first noninvasive study to clarify the complex spatiotemporal activities relating movements in humans using a multi-channel MEG system.

[Prevalence of antimicrobial resistance among clinical isolates of Streptococcus pneumoniae in a children's hospital]

Eleven hundreds and seventy-six strains of Streptococcus pneumoniae were isolated from pediatric clinics of Chiba Children's Hospital during 1990 through 1995. Annual penicillin-resistant rates of these strains were as follows; 24.0% (1990), 29.0% (1991), 36.2% (1992), 55.8% (1993), 58.6% (1994), and 59.3% (1995). Overall penicillin-resistance during these 6 years was 45.8%. Nine out of 11 cases of systemic pneumococcal infections were due to penicillin-resistant S. pneumoniae (PRSP) during the same period. Of PRSP strains, their PCG-MIC levels had become higher and their spectra of resistance had expanded not only to beta-lactam but also to non-beta-lactam antimicrobials. Although panipenem was the most efficacious antibiotics in this study and was recommended currently to use in the case of pneumococcal meningitis, it should be noted that a strain with high-level MIC (2 micrograms/ml) had emerged in 1995. Close surveillance of pneumococcal antimicrobial susceptibility including panipenem is necessary.

Metabolism of anandamide, an endogenous cannabinoid receptor ligand, in porcine ocular tissues

Anandamide (arachidonylethanolamide) is an endogenous ligand for cannabinoid receptors, and exerts various cannabimimetic activities. Since cannabinoids and anandamide were pharmacologically active with the eye, we examined metabolism of anandamide in a variety of porcine ocular tissues. In the presence of ethanolamine, [14C]arachidonic acid was converted to [14C]anandamide by a homogenate of retina, choroid, iris, optic nerve and lacrimal gland with a specific enzyme activity of 1.9-4.2 nmol min-1 mg-1 protein at 37 degrees C. On the other hand, [14C]anandamide was hydrolysed to [14C]arachidonic acid by a homogenate of each tissue with a specific enzyme activity of 1.2-3.5 nmol min-1 mg-1 protein. Thus, both activities of anandamide synthase and hydrolase were found in these ocular tissues. As for the subcellular distribution, the two enzyme activities were mostly recovered in particulate fractions rather than the cytosol. With the retina microsome palmitic acid was converted to its ethanolamide at a lower rate than arachidonic acid, and palmitoylethanolamide was less active than anandamide as a substrate for the hydrolase.

[A case report of surgical treatment for aneurysm of the brachiocephalic artery associated with tracheal stenosis]

A 76-year-old woman, diagnosed with aneurysm of the brachiocephalic artery thirteen years ago, encountered tracheostenosis due to tracheal compression induced by an increase in size of the aneurysm. Complete aneurysmectomy with graft replacement under cardiopulmonary bypass failed to improve the bronchostenosis. This was attributed to tracheomalacia developed as a result of malatic tracheal cartilages. On day 14 post operation, external fixation of the trachea with an autografted costa relieved her condition markedly. Aneurysm of the brachiocephalic artery is rare and asymptomatical. As such, the present case report suggests that patients with such a aneurysm should be promptly operated to present both the risk of arterial rupture and unfavorable compression of adjacent organs.

Regulation of cyclodextrin glucanotransferase synthesis in Bacillus ohbensis

The production of cyclodextrin glucanotransferase (CGTase) by Bacillus ohbensis is dependent on the presence of starch and inhibited by glucose in the medium. Northern blot analysis revealed that the CGTase gene (cgt) was transcribed to almost the same level irrespective of the presence or absence of starch, but glucose completely repressed the transcription. Furthermore, a relatively high amount of CGTase protein was detected on Western blotting only in the medium with starch, showing the lack of posttranslational control of the CGTase activity. These findings suggest some starch induction mechanism for the cgt gene, possibly at the posttranscriptional level, besides negative transcriptional regulation by glucose.

[Decision support of clinical laboratory test by object-oriented data base]

We have constructed an object-oriented database system, using prescription, lab test result, and disease registry data, transmitted from the order entry system of Hamamatsu University Medical School Hospital. It serves not only numeric data but also semantics of laboratory results. The database system has a feature to categorize each data into structured hierarchies of attributes. By this, the user can retrieve abstract level descriptions such as "prescriptions of anti-inflammation medicines, suppository only", "any kind of gastric ulcer", etc., which is expected to be useful for researchers and students. In transferring order entry data from HIS, HL7-ASTM E1238 standard data formats using the Japan Association of Clinical Pathology lab test item code are utilized, proving this system's transferability to other hospitals. This is the first real use implementation of an object-oriented data base in a clinical setting, and results are promising in terms of providing an intelligent clinical database. Also discussed are future trends of clinical master files, hospital administrative tools, and multi vendor configurations of HIS.

Purification and properties of beta-fructofuranosidase from Clostridium perfringens

beta-Fructofuranosidase [EC 3.2.1.26] in Clostridium perfringens was induced in the presence of sucrose and suppressed in the presence of glucose or maltose. The enzyme seems to be present in protoplasm in a soluble state. The beta-fructofuranosidase from C. perfringens cells grown on sucrose was purified by ammonium sulfate precipitation. DEAE-cellulose chromatography, Sephadex G-150 gel filtration, and hydroxylapatite chromatography to a homogeneous state. The molecular weight was 37,000 by gel filtration using Sephadex G-150 and by SDS-polyacrylamide gel electrophoresis. The amino acid composition is not much different from those of other microorganisms, but the Glx content was a little higher. The enzyme was inhibited by heavy metals, such as Hg2+, Cu2+, and Ag+, as well as pCMB; the activity was restored by incubating with mercaptoethanol. Fructose and amines including Tris and aniline had inhibitory effects.

Efficacy of a selective histamine H2 receptor agonist, dimaprit, in experimental models of endotoxin shock and hepatitis in mice

Dimaprit, a selective histamine H2 receptor agonist, was examined in experimental models of endotoxin shock and hepatitis in mice. Injection of lipopolysaccharide (8 mg/kg i.v.) into Balb/c mice resulted in an elevation of plasma tumor necrosis factor-alpha (TNF-alpha), reaching the maximal level at 1 h post-lipopolysaccharide (1147 U/ml). Oral administration of dimaprit 200 mg/kg, 1 h prior to lipopolysaccharide challenge, inhibited the increase in plasma TNF-alpha by 71% and also the survival rate was increased to 62.5% from 8.3% in the disease control. In a mouse hepatitis model, simultaneous injection of galactosamine (700 mg/kg i.v.) and lipopolysaccharide (3 micrograms/kg i.v.) into Balb/c mice caused an increase in plasma TNF-alpha, peaking at 1 h, followed by an elevation of L-alanine aminotransferase (E.C.2.6.1.2) activity at 4 h onward. Oral administration of dimaprit 200 mg/kg, 1 h prior to galactosamine and lipopolysaccharide, reduced the increase in plasma TNF-alpha by 99% and L-alanine aminotransferase by 82%. In vitro, dimaprit dose dependently inhibited the production of TNF-alpha in mouse peritoneal macrophages and human peripheral blood monocytes stimulated with lipopolysaccharide with IC50 values of 1 microM. The decrease in TNF-alpha production by dimaprit was reversed by cimetidine, a histamine H2 receptor antagonist. Dimaprit dose dependently suppressed TNF-alpha mRNA in human peripheral blood monocytes. These results suggest that activation of the histamine H2 receptor downregulates the production of TNF-alpha, and that histamine may be an important regulator in pathological conditions in which TNF-alpha plays an important role.

Effects of movement and movement imagery on somatosensory evoked magnetic fields following posterior tibial nerve stimulation

We examined the "gating" effects caused by active and passive movements of toes and by "movement imagery" (mental moving of the toe without actual movements) on somatosensory evoked magnetic fields (SEFs) following stimulation of the posterior tibial nerve in normal subjects. Active and passive movements significantly attenuated the short- and middle-latency cortical components (P < 0.001) with no latency change, and the effects of the active movements were larger than those of the passive movements. In contrast, the subsequent long-latency component with a latency of about 100 ms was enhanced only by the active movements. Therefore, both centrifugal and centripetal mechanisms should be considered. The gating effects by movements on all components may occur in the primary sensory cortex (SI) in the hemisphere contralateral to the stimulated nerve, because all of the equivalent current dipoles (ECDs) of the components in the "control" and each "interference" waveform were located there. Active movements of the toes contralateral to the stimulated nerve caused no significant gating effect. The short-latency components were not consistently changed by "movement imagery", but the middle- and long-latency components were enhanced. Their ECDs were located in the SI contralateral to the stimulated nerve and in the SII in bilateral hemispheres. Therefore, we speculated that brain responses to somatosensory stimulation, particularly components generated in SII, were affected by volitional changes.

[A case of corticobasal degeneration presenting with primary progressive aphasia]

We report a 64-year-old right-handed woman whose initial symptom was slowly progressive aphasia without generalized dementia and who was subsequently diagnosed as having corticobasal degeneration (CBD). Neurological examination revealed disturbed vertical gaze, dysarthria, rigidity of the right upper extremity, and bilateral instinctive grasp reaction. Neuropsychological assessment disclosed Broca's aphasia, buccofacial apraxia, and memory disturbance. MRI of the brain showed atrophy of the frontotemporal lobes, which was more severe on the left than on the right, especially the left inferior frontal gyrus. In most reported cases of CBD, the initial symptom is motor dysfunction of the unilateral upper or lower extremity. However, we should be cautious that among cases with CBD, there have been rare cases that begin with progressive aphasia alone. In our case, the atrophied region of the cerebral cortex was most severe around the left inferior frontal gyrus. In a few reported cases with the initial symptom of aphasia, the atrophied region corresponded considerably to the type of the aphasia. On the other hand, in those whose initial symptom was mainly motor dysfunction of the unilateral extremity, the atrophied region was remarkable in the posterior part of the frontal lobe and parietal lobe. Therefore, we suggest that in CBD the distribution of the cerebral cortical lesions differs in accordance with whether the initial symptom is motor disturbance or aphasia, and that the type of aphasia corresponds to the location of the cortical lesion.

Cloning and sequencing of an alpha-glucosidase gene from Aspergillus niger and its expression in A. nidulans

We have cloned an extracellular alpha-glucosidase gene from Aspergillus niger with oligonucleotide probes synthesized on the basis of the determined peptide sequences. The nucleotide sequence revealed an open reading frame of 985 amino acids split with three introns, and the deduced amino acid sequence was nearly identical to that of the alpha-glucosidase previously determined. The cloned gene was introduced into Aspergillus nidulans, and its expression in the transformants was shown to be regulated by the carbon sources in the medium, suggesting that a common regulatory expression system is shared by these two species as is the case of other starch-degrading enzymes of Aspergillus species.

Modulation of magainin 2-lipid bilayer interactions by peptide charge

Magainin 2, an antimicrobial peptide from Xenopus skin, assumes an amphiphilic helix when bound to acidic phospholipids, forming a pore composed of a dynamic, peptide-lipid supramolecular complex [Matsuzaki et al. (1996) Biochemistry 35, 11361-11368]. Upon the disintegration of the pore, a fraction of the peptide molecules stochastically translocates across the bilayer (Matsuzaki, et al., 1995). In order to investigate the effects of peptide charge on the magainin 2-lipid bilayer interactions, we synthesized four magainin 2 analogs with different charges (0-6+). MG0: K10E, K11E, F12W-magainin 2. MG2+: K10E, F12W-magainin 2. MG4+: F12W-magainin 2. MG6+: F12W, E19Q-magainin 2 amide. An increase in charge resulted in a stronger binding of the peptide to the negatively charged membranes, suggesting that electrostatic attractions play a crucial role in the binding process. The helical stability in a trifluoroethanol/buffer mixture was decreased with increasing positive charge because of electrostatic repulsions between the closely spaced positive side chains, whereas the helicity in the lipid bilayer was much higher and appeared to be independent of the peptide charge. However, enhanced repulsions between the highly positively charged helices destabilized the pore. Therefore, the efficiency of the most basic peptide (MG6+) to translocate across the bilayer was the greatest by virtue of the short life span of its pore and the very tight membrane binding. The charge distribution of wild-type magainin 2 was found to be so designed as to exhibit the maximal lytic activity by simultaneously achieving a strong binding and a moderate pore stability.

Determination of [D-Ala2,D-Leu5]enkephalin and the metabolites containing C-terminal D-leucine by high-performance liquid chromatography

A high-performance liquid chromatographic procedure has been developed for the determination of [D-Ala2,D-Leu5]enkephalin (DADLE) and the fragments containing D-leucine in rat blood. The procedure was applied to the determination of blood levels of [3H-D-Leu5]DADLE and the C-terminal fragments after intravenous administration of [3H-D-Leu5]DADLE to a rat. Unlabelled DADLE and the C-terminal fragments were spiked as carriers to rat blood samples and the blood samples were extracted with 1% trifluoroacetic acid in methanol. The recoveries from rat blood were quantitative for all compounds. DADLE and the C-terminal four fragments were well separated on a reversed-phase column with gradient elution using a mobile phase composed of 0.14% HClO4 and acetonitrile.

Bony foramina facilitate magnetic stimulation: an experimental cat sciatic nerve model

We have established an experimental bony foramen model in vivo using a cat sciatic nerve, a section of skull bone and a column made from methylmethacrylate. In each model, a foramen-like slit or fissure was created. Motor responses of the cat right gastrocnemius were elicited with a figure-of-8-shaped magnetic coil. Very high intensities of magnetic stimulation were necessary to evoke motor responses with the coil placed on the thigh. However, when the bone section or methylmethacrylate column was placed under the thigh muscle layer with the sciatic nerve fitted into the foramen-like slit or fissure, motor responses could be elicited with a smaller intensity of magnetic stimulation. Despite changes in stimulation intensity or shifts in the magnetic coil, the latency of the motor responses remained constant. By comparing the latency with the electrical recording, the site of excitation was predicted to be at the exit of the foramen. Our studies have confirmed that bony structures, especially bony foramina, facilitate excitation of the nerve by magnetic stimulation and that the exit of the foramen could be the preferential site for magnetic stimulation.

Pharmacokinetics of (+/-)-4-diethylamino-1,1-dimethylbut-2-yn-1-yl 2-cyclohexyl-2-hydroxy-2-phenylacetate monohydrochloride monohydrate. 3rd communication: plasma concentrations of the unchanged drug and its deethylated metabolite in rats, dogs and monkeys

1. The plasma concentrations of NS-21 ((+/-)-4-diehtylamino-1, 1-dimethylbut-2-yn-1-yl 2-cyclohexyl-2-hydroxy-2-phenylacetate monohydrochloride monohydrate, CAS 129927-33-4) and its deethylated metabolite (RCC-36) after intravenous and oral administrations of (S/R)-NS-21 were measured in rats, dogs and monkeys. After intravenous administration, the plasma concentrations of NS-21 decreased biexponentially. The half-lives of NS-21 in the elimination phase were 2.2 h in rats, 5.3 h in dogs and 15.4 h in monkeys. After oral administration, the systemic availabilities were 4% in rats, 22% in dogs and 6% in monkeys. After intravenous administration, the plasma concentrations of RCC-36 were much lower than those of the unchanged drug in all the animal species tested. In contrast, after oral administration, the plasma concentrations of RCC-36 were comparable to those of the unchanged drug in rats and dogs, and were higher in monkeys. This result suggests that RCC-36 is mainly produced by the first-pass effect. 2. The plasma concentrations of NS-21 and RCC-36 after intravenous and oral administrations of (S)- or (R)-NS-21 were measured in dogs. The AUC value of the unchanged drug after intravenous administration of (R)-NS-21 was about twice as large as that of (S)-NS-21. After oral administration, the systemic availabilities of (S)- and (R)-NS-21 were 17 and 22%, respectively. There were no differences in the serum binding between (S)- and (R)-NS-21 in any of the animal species tested including humans. (S)- and (R)-NS-21 were mainly converted to RCC-36 and a 4-cyclohydroxylated metabolite (NS-21-4-OH) in hepatic microsomes of rats, dogs and monkeys. There were no marked differences in the N-deethylation of (S)- and (R)-NS-21 in all the animals. In contrast, (S)-NS-21 was converted to NS-21-4-OH more preferentially than (R)-NS-21 only in dogs. These findings indicate that the stereo-selective disposition of NS-21 in dogs is due to the stereo-selective cyclohydroxylation of NS-21.

Effects of chronic treatment with carvedilol on smooth muscle tone and endothelium-dependent relaxation of aorta in stroke-prone spontaneously hypertensive rats

Effects of chronic treatment of stroke-prone spontaneously hypertensive rats (SHRSP) with carvedilol, an agent which has both alpha and beta-adrenoceptor blocking actions, on spontaneous muscle tone and on structural and functional abnormalities of endothelium were studied. The treatment of SHRSP with the drug of the dose of 30 to 200 mg/kg/day lowered the blood pressure significantly. Spontaneous muscle tone in endothelium-removed preparation disappeared by the treatment. Noradrenaline-induced contraction was depressed by the treatment in endothelium intact preparation but not in endothelium removed preparation. The treatment prevented the structural and functional abnormalities of endothelium. Similar results were obtained by the treatment with propranolol. These results indicate that carvedilol prevented abnormal contraction of SHRSP aorta through protective effects on smooth muscle and endothelium. These effects may play roles in blood pressure lowering effect of carvedilol.