[Changes in urine oxygen tension (PuO2) during anesthesia with isoflurane and sevoflurane]

Leonhardt and coworkers have suggested that PuO2 may indicate degree of renal medullary perfusion and function. The changes in PuO2 during N2O-O2-isoflurane anesthesia (GOI) and N2O-O2-sevoflurane anesthesia (GOS) were studied in 20 patients (GOI group: 10 cases, GOS group: 10 cases) who underwent elective surgeries. In the GOI group, PuO2 decreased significantly 30 and 60 minutes after the beginning of surgical incision, and it returned to the previous value immediately after the cessation of isoflurane. In the GOS group PuO2 decreased starting 30 minutes after the beginning of surgical incision until 10 minutes after the cessation of sevoflurane. These results suggest that isoflurane and sevoflurane administration caused a reduction in renal medullary perfusion, and that the low perfusion during sevoflurane anesthesia lasted longer than during isoflurane anesthesia. Measurement of PuO2 has a number of problems, but we believe that PuO2 is useful as an indicator of renal medullary blood flow.

Identification of bovine serum transferrin phenotypes by polyacrylamide gel isoelectric focusing (PAGIEF)

Each of four common homozygous bovine serum transferrins Tf A, Tf D1, Tf D2, and Tf E gave only two main bands in polyacrylamide gel isoelectric focusing (PAGIEF). This is considered to be due to the co-migration of the main components 2a and 3a with the main components 2b and 3b, respectively, in PAGIEF. Ten phenotypes, which are controlled by four alleles TfA, TfD1, TfD2, and TfE, were distinguishable from each other in PAGIEF.

Endogenous synthesis of N-methylnorsalsolinol in rat brain during in vivo microdialysis with epinine

The in vivo metabolic pathway for the synthesis of N-methylnorsalsolinol, an analogue of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), was studied in the rat brain. N-Methyldopamine (epinine) was perfused at the striatum of the rat brain by in vivo microdialysis. N-Methylnorsalsolinol (NMNSAL) was identified in the brain dialysate after epinine perfusion using gas chromatography-selected-ion monitoring mass spectrometry (GC-SIM-MS). We demonstrated that NMNSAL could be synthesized from epinine with an aldehyde by the Piclet-Spengler condensation reaction in the rat brain.

Serial changes in coagulant activities after thrombolytic therapy for acute myocardial infarction

Early reocclusion and bleeding complications are still unresolved problems in thrombolytic therapy for acute myocardial infarction (AMI). In the present study, 16 patients treated with either fibrin-specific tissue-type plasminogen activator (t-PA) or nonspecific urokinase (UK) were studied to determine the effects of thrombolytic therapy on serial hemostatic states. Hemostatic states of each patient were estimated by measuring various plasma markers at one- to two-hour intervals during the first six hours of therapy, daily during the next three days, and subsequently on day 7. Two markers of plasma thrombin generation, thrombin antithrombin III complex (TAT) and prothrombin fragment 1 + 2 (F 1 + 2), showed an activated coagulant state immediately after thrombolytic therapy. The amount of thrombin generation indicated by these markers showed significant positive correlation with direct markers of fibrinolysis such as fibrin degradation products (FDP), while it did not show any correlation with the markers for plasmin generation. The potential for coagulation as indicated by prothrombin time (%) decreased with thrombolysis using fibrin nonselective agents, owing perhaps to destruction of coagulant factors by free plasmin. Fibrinolytic activity induced by thrombolytic therapy for AMI caused transient activation of the coagulant system, which could contribute to early reocclusion. Fibrin nonselective agents decreased the potential for coagulation by destroying clotting factor through the generation of free plasmin. These data provide theoretical support for simultaneous administration of anticoagulant therapy with fibrin-specific thrombolytic agents.

The potent depressant effects of N3-phenacyluridine in mice

The hypnotic activity of N3-phenacyluridine in 2.0 mumol/mouse by intracerebroventricular (i.c.v.) injection was 20 times stronger than that of known N3-benzyluridine. In 0.5 mumol/mouse, i.c.v., this compound strongly potentiated both pentobarbital- and diazepam-induced sleep as compared to N3-substituted uridines, including N3-benzyluridine. Furthermore, the compound caused motor incoordination as well as decreasing spontaneous activity in the same dose. These results indicate that among the N3-substituted uridines and related compounds previously reported, N3-phenacyluridine possesses potent depressant effects.

Template-dependent peptide formation on ribosomes catalyzed by pyridine

We found that poly(U)-dependent polyphenylalanine synthesis on Escherichia coli ribosomes was extremely accelerated in the presence of a high concentration of pyridine. In this reaction, chemical energy sources, such as ATP and GTP, and soluble protein factors are not required, but the template and ribosomes are essential for the progress of the reaction. The reaction was inhibited by the antibiotics which inhibit the usual bacterial translation process on the ribosomes. These observations clearly demonstrate that the pyridine-catalyzed amino acid condensation reaction proceeds on the ribosome.

Myelodysplastic syndrome associated with immunoblastic lymphadenopathy-like T-cell lymphoma: simultaneous clinical improvement with chemotherapy

A 75-year-old woman presented with anemia, lymphadenopathy, hepatomegaly and lingual tumor, but no constitutional symptoms. The laboratory data showed pancytopenia and polyclonal hypergammaglobulinemia. A bone marrow aspirate represented an apparent myelodysplastic syndrome (MDS) feature, specifically, refractory anemia with excess of blasts. A lymph-node biopsy revealed the disappearance of normal architecture, small arborizing blood vessels, large lymphoid cells with prominent cytoplasm (so-called pale cells) and a clonal proliferation of T-lymphocytes. The patient was diagnosed as having MDS associated with immunoblastic lymphadenopathy (IBL)-like T-cell lymphoma. She was subsequently treated with cyclophosphamide, adriamycin, vincristine and prednisolone for lymphoma which successfully induced a remission of not only the T-cell lymphoma but also the MDS. The case suggested that MDS might be a paraneoplastic complication of IBL-like T-cell lymphoma.

Effects of chemical modification of arginine residues outside the active site cleft of ricin A-chain on its RNA N-glycosidase activity for ribosomes

Ricin A-chain, a protein that inactivates ribosomes by a specific RNA N-glycosidase activity, has been shown to be inactivated by chemical modification of a few arginine residues. When two or fewer arginine residues in the A-chain were modified with [14C]phenylglyoxal, arginines at positions of 193, 196, 213, and 234/235 were found to be modified, from amino acid compositions and radioactivities of the modified peptides that were obtained by cyanogen bromide cleavage followed by tryptic and chymotryptic digestion. All these arginines have side chains outside the active site cleft; the side chain of Arg213 is adjacent to the edge of the cleft, while other modified arginines are located on the opposite side of the cleft. Kinetic analysis showed that the modification of two arginine residues caused a 8-fold loss in kcat with a 3-fold increase in Km, suggesting that this modification mainly decrease the rate of depurination with an additional effect on the affinity for ribosomes. Neither the environment of tryptophan 211 at the bottom of the cleft nor an interaction of adenine with the cleft was changed by this modification, as judged by fluorescence spectroscopy, suggesting that a conformational change of the catalytic site does not occur upon the modification. These results, taken together with other works, suggest that some of the above arginine residues outside the active site cleft may additively contribute to the catalysis of depurination and/or the initial formation of the A-chain/ribosome complex.

The effect of bunazosin on monocrotaline-induced pulmonary hypertension in rats

In order to estimate the long-term hemodynamic and histologic effects of bunazosin hydrochloride on primary pulmonary hypertension (PPH), for which effective internal therapy has not yet been proposed, we produced subacute pulmonary hypertension in 6 week old Sprague-Dawley rats by injecting one dose of monocrotaline. Bunazosin (10 mg/kg) was administered intraperitoneally every day and bodyweight and hemodynamic parameters were measured. Right ventricle (RV) and left ventricle with septum (LV +S) were weight separately. Medial thickness of the small pulmonary artery was calculated. In the bunazosin group, the increase of right ventricular systolic pressure (RVSP) as pulmonary arterial systolic pressure and the ratio of RVSP to pulmonary flow were limited, without causing systemic hypotension, compared to the control group. Weight ratio of RV/(LV +S) had a tendency to be limited in the bunazosin group. As for medial thickness, there was no significant difference between the two groups. It may be concluded that bunazosin hydrochloride should be considered for clinical trials in treatment of PPH in humans.

A study of the complications induced by conventional and disposable contact lenses

We reviewed the charts of 23,068 patients (45,580 eyes) who were prescribed contact lenses in order to investigate the incidence of corneal complications in Japan. This population of patients included wearers of various types of conventional contact lenses as well as disposable extended wear lenses and daily disposable lenses. The rate of corneal complications and 95% confidence interval for each lens group were: polymethylmethacrylate (PMMA) lenses, 15.8% (358 of 2,267 eyes, 14.3-17.3%); rigid gas permeable lenses, 10.5% (3,191 of 30,459 eyes, 10.2-10.8%); acrylelastomer lenses, 7.2% (nine of 124 eyes, 2.7-11.7%); HEMA lenses 8.5% (534 of 6,261 eyes, 7.8-9.2%); high water content lenses, 4.0% (103 of 2,591 eyes, 3.6-4.4%); weekly disposable lenses, 4.9% (146 of 2,985 eyes, 4.1-5.7%); and daily disposable lenses, 2.5% (22 of 893 eyes, 1.5-3.5%). PMMA lenses had a significantly higher rate of corneal complications compared with other lenses, whereas the daily disposable lens had a significantly lower rate for the same. The majority of corneal complications for all types of lenses consisted of superficial punctate keratopathy, and there were no cases of corneal ulcers.

Recombinant rat nucleoside diphosphate kinase isoforms (alpha and beta): purification, properties and application to immunological detection of native isoforms in rat tissues

We previously demonstrated that at least two isoforms of nucleoside diphosphate (NDP) kinase, the products of two different tandemly arrayed genes, are present in rat. To understand the physiological role of each isoform, some biochemical properties of recombinant rat NDP kinase alpha- and beta-isoforms, produced in large amount, were studied. cDNAs of the two isoforms were inserted in an expression vector pET3b and recombinant enzymes were overproduced in Escherichia coli. Their primary structures were different from the native enzymes in that the latter suffer from modification of the NH2-terminal end. The two recombinant isoforms were purified from the cell lysate to apparent homogeneity by ammonium sulfate fractionation followed by three successive column chromatographies. Despite their extreme similarity in the amino-acid sequences, the two showed somewhat different enzymic properties in terms of di- and triphosphate nucleotide substrate specificity. They showed similar mobilities on SDS-PAGE as expected from their calculated molecular weight (alpha-isoform, 17,283 versus beta-isoform, 17,192) but differed in isoelectric point (alpha-isoform, pI 6.7; beta-isoform, pI 7.8) and heat stability. Polyclonal antibody which reacted with both isoforms and alpha-isoform-specific monoclonal antibodies differentially recognized native enzymes from rat tissues after the tissue extracts were separated by isoelectric focusing gel electrophoresis under a denaturation condition. The results showed that the alpha-isoform, though its amount varied from one tissue to another, was the major form in rat tissues examined compared with the beta-isoform which was detectable in brain and testis. There was no preference in their subcellular localization when examined with myelin, synaptosomal supernatant and total homogenate fractions from the rat cerebrum and cerebellum.

Functional and structural role of a tryptophan generally observed in protein-carbohydrate interaction. TRP-62 of hen egg white lysozyme

In order to elucidate the role of the aromatic ring in recognition of the sugar ring, Trp-62 of hen egg white lysozyme, which is proposed on the basis of x-ray crystallography data to make contact with a sugar ring through van der Waals interaction, was replaced with aliphatic amino acids (Leu, Ile, Val, and Ala) and Gly by site-directed mutagenesis. In spite of the loss of the aromatic effect, these mutant lysozymes, except for the Trp-62-->Gly mutant, showed higher bacteriolytic activity than the wild-type lysozyme. Furthermore, the Trp-62-->Gly mutant still retained appreciable bacteriolytic activity. On the other hand, by these replacements, the enzymatic activities toward non-charged substrates were markedly reduced. Additionally, the side-chain structure of position 62 was found to be largely responsible for recognition of a saccharide ring in its active site cleft. NMR analysis of the Trp-62-->Leu and Trp-62-->Gly mutants indicated that the structural effects of Trp-62 replacements were localized in the loop region around position 62 and the part of the beta-sheet containing the hydrogen bonding network important for enzymatic activity. Thus, we conclude that Trp-62 not only interacts with oligosaccharide through van der Waals contact, but also maintains the local structural conformation to produce the lysozyme-oligosaccharide interaction.

cDNA cloning and sequence of CYP2C29 encoding P-450 MUT-2, a microsomal aldehyde oxygenase

A cDNA clone encoding a cytochrome P-450 (P-450) isozyme was isolated from a mouse liver cDNA library. This P-450, designated CYP2C29, the first member of the mouse CYP2C subfamily to be reported, contained the complete coding region of 490 amino acid residues. The deduced amino acid sequence of CYP2C29 exhibited 83% identity with that of the rat CYP2C7 and had an N-terminal sequence identical to that of P-450 MUT-2, a microsomal aldehyde oxygenase. Two peptides, derived from BrCN cleavage of P-450 MUT-2, were also identical to the cDNA deduced protein of CYP2C29. These results indicate that CYP2C29 cDNA encodes P-450 MUT-2.

Dyspnea in acute bronchial asthma in an emergency room

Pulmonary function, arterial blood gases, and pulse rate were prospectively compared with dyspnea perceived by patients before and after emergency room treatment for acute asthma in 83 episodes. Subjective degree of dyspnea was rated on a modified Borg scale. Before treatment, all spirometry (FVC, FEV1, and peak expiratory flow rate) and arterial blood gas (PaO2, PaCO2, and bicarbonate) data as well as pulse rate were significantly correlated with modified Borg scale, but only PaCO2 showed significant correlation (P < .001) in a multivariate analysis. After treatment, only PaO2 was significantly correlated with modified Borg scale (P = .008) in a multivariate analysis, and pulse rate showed correlation of borderline significance (P = .06). In another 37 episodes of relapsed acute asthma, the correlations between laboratory data and modified Borg scale were very weak, especially after treatment. We conclude that dyspnea expressed by asthmatic patients in an emergency room might be reflecting different mechanisms as treatment is performed. Although it should be one useful guide in emergency evaluation, it must be recognized that dyspnea in the same patient could mean different abnormalities.

Pharmacological and model-based interpretation of neuronal dynamics transitions during sleep-waking cycle

Power spectral analysis has been applied to spontaneous single neuronal activities during the sleep-waking cycle in various regions of the cat's central nervous system. During slow-wave sleep (SWS), the spontaneous activities of many neurons had a white noise-like power-spectral density profile in a very low frequency range (0.01-1.0 Hz) whereas, during rapid-eye-movement sleep (REMS), they showed a 1/f-like spectral pattern. This spectral transition between SWS and REMS was hypothesized to depend on the influence of serotonergic and cholinergic neuronal activity which is considered to modulate various brain functions. According to both pharmacological experiments and simulation studies with a neural network model, it was concluded that the serotonergic system may have a function to eliminate slow fluctuations in neuronal activity in wide areas, from the reticulo-thalamo-neocortical to the limbic systems. Consequently, simple signal processing of spontaneous neuronal activity has elucidated an important neurophysiological fact, which may lead to a principle of the basic brain function and its mechanism.

Increased interleukin-1 activity in the injured vitamin A-deficient cornea

Injury to a vitamin A-deficient cornea leads to severe acute inflammation often culminating in ulceration. We report on possible regulatory mechanisms involved in the pathogenesis of corneal inflammation in vitamin A deficiency. Thymocyte comitogenic assay and interleukin (IL)-6 induction in corneal fibroblasts have shown that thermally injured and mechanically abraded vitamin A-deficient rat corneas produce much higher levels of an IL-1-like factor as compared with uninjured or injured, normal control corneas. This was confirmed by antibody capture enzyme immunoassay, which detected high levels of IL-1 alpha and IL-1 beta in injured vitamin A-deficient corneas. To our knowledge this is the first report describing the induction of IL-1 in the vitamin A-deficient cornea by thermal and mechanical injuries. When mechanically injured corneas were screened for chemotactic activity, they were found to contain significantly higher levels of a chemoattractant as compared with similarly injured, normal control corneas. Chemotactic activity [expressed as a percentage of a known chemotactic tripeptide, formyl-methionyl-leucyl-phenylalanine (fMLP), found in medium harvested from vitamin A-deficient corneas] averaged 58.8 +/- 8.9% (SEM) as compared with 12.6 +/- 5.4% in medium conditioned by normal corneas. Checkerboard analysis confirmed that the activity in vitamin A-deficient cornea conditioned medium was chemotactic and not chemokinetic. These results demonstrate a correlation between IL-1 levels and severity of inflammation in the injured vitamin A-deficient rat cornea.

Preferential localization of c-kit product in tissue mast cells, basal cells of skin, epithelial cells of breast, small cell lung carcinoma and seminoma/dysgerminoma in human: immunohistochemical study on formalin-fixed, paraffin-embedded tissues

Eighteen hundred and eighty-four cases of human solid tumours and 833 samples of normal human tissues, formalin-fixed and paraffin-embedded, were examined immunohistochemically for expression of c-kit oncogene product using polyclonal antibody against synthesized c-kit peptide. Seminoma/dysgerminoma and small cell lung carcinoma (SCLC) show preferential c-kit expression at 92% and 36% frequency, respectively, whereas only sporadic cases of cervical carcinoma and non-SCLC lung carcinoma show c-kit positivity. A normal tissue counterpart positive for c-kit product is detected in the testis (spermatocyte) and ovary (oocyte) but not in the lung or the cervix. In contrast, normal epithelial cells of the breast, skin basal cells and tissue mast cells harbour c-kit product, but transformed cells of the former two are largely deficient in the c-kit protein. One hundred and thirty-nine neuroendocrine tumours and 39 non-pulmonary small cell carcinomas were all negative, except for two cases of neuroblastoma. This indicates a distinct character for SCLC in c-kit expression. The c-kit product may be a useful marker in diagnostic pathology of seminoma/dysgerminoma and SCLC among human solid tumours, and in distinction of SCLC from non-pulmonary small cell carcinoma.

Immunohistochemical localization of glutathione peroxidase in infarcted human brain

This is the first report which demonstrates the presence of glutathione peroxidase in the autopsied brain of 5 patients without cerebral infarction and 21 patients with cerebral infarction by the indirect enzyme-labeled antibody technique with monoclonal antibody to human glutathione peroxidase. In 2 out of 5 patients without cerebral infarction, a weak reaction for glutathione peroxidase was demonstrated both in neurons and glia. In 6 patients who had died within 5 days after stroke, no staining was observed in infarcted brain tissue except in macrophages. In all 15 patients who had died more than 6 days after stroke, however, a reaction for glutathione peroxidase was demonstrated in the cytoplasm of glial cells in the marginal area around the infarction, and there was a patchy reaction in the cytoplasm of macrophages in the core lesion. These results suggest that glutathione peroxidase in glial cells of the marginal area around the infarction may play a protective role against lipid peroxidation after cerebral infarction, or alternatively, may be involved in the healing process after ischemia.

Photosensitive epilepsy in children

We performed a retrospective analysis of 17 children with photosensitive seizures (PSS) who had been followed for more than 3 years (mean: 9 years). PSS were verified in all patients by simultaneous video-EEG monitoring. The seizures were precipitated by flickering stroboscopes (14 patients) or were induced by patients themselves (3) with head-nodding in front of illumination, blinking at television or close viewing of striped patterns. PSS consisted of myoclonic seizures (eight patients), generalized tonic-clonic convulsions (5), partial seizures (3) or atypical absence (1). According to the International Classification of Epileptic Syndrome, three patients were classified as having severe myoclonic epilepsy in infancy and five as having juvenile myoclonic epilepsy. The remaining nine could not be categorized as any specific epileptic syndrome. Children with age of the onset of epilepsy at 7 years or younger tended to suffer intellectual deficit in addition to intractable seizures.

Temporal approach for reduction of zygomatic fractures. Clinical results and advantages of the technique

We have used closed reduction based on Gillies' method using an original Y-shaped zygomatic elevator in 50 cases after radiographic evaluation of the displacement by three directional radiography. No patients had residual restriction of mandibular motion, double vision or facial asymmetry. Radiography showed poor reduction in two cases, and displacement of the initial reduction in three. In all other cases, satisfactory results were achieved.

Potential of O6-methylguanine or O6-benzylguanine in the enhancement of chloroethylnitrosourea cytotoxicity on brain tumours

The purine analogues O6-methylguanine and O6-benzylguanine are well-known as a chemical modulator of the DNA repair enzyme O6-methylguanine-DNA methyltransferase. Inactivation of the enzyme by O6-methylguanine or O6-benzylguanine is expected to enhance sensitivity of tumours to chloroethylnitrosoureas. We studied the effect of O6-methylguanine or O6-benzylguanine pretreatment on cytotoxicity of 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3- (2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) in brain tumour cells and transplanted brain tumours. Two-hour exposure of O6-methylguanine at higher concentrations (500 microM, 1,000 microM) increased ACNU cytotoxicity by only 2 times in ACNU-resistant C6-1 brain tumour cells. O6-Benzylguanine at concentrations between 10 and 100 microM markedly enhanced the cytotoxic effect. The ACNU sensitivity of the tumour cels pretreated with O6-benzylguanine was 5-40 times that of the cells without O6-benzylguanine. Neither O6-methylguanine nor O6-benzylguanine appreciably enhanced ACNU cytotoxicity of 9 L cells, which were originally sensitive to ACNU. Intracarotid ACNU with O6-methylguanine or O6-benzylguanine decreased proliferating activity of transplanted C6-1 brain tumours significantly during 48 hours. O6-Benzylguanine pretreatment resulted in a greater degree of suppression for a long time. The C6-1 tumours treated only with intracarotid ACNU showed a transient inhibition and a rapid regrowth during 24 hours after the treatment. These results indicate that O6-methylguanine or O6-benzylguanine increases ACNU cytotoxicity and may be feasible for effective combination therapy with chloroethylnitrosourea in the chemotherapy of malignant brain tumours.

[Effects of pranidipine (OPC-13340), a novel 1,4-dihydropyridine derivative Ca-antagonist, on isolated porcine coronary contraction and acute myocardial ischemia in the pig]

Pranidipine (OPC-13340) is a novel, potent and long-acting 1,4-dihydropyridine derivative Ca-antagonist being developed for clinical use as an antihypertensive and antianginal drug. Pranidipine at concentrations of 10(-9) - 10(-6) M suppressed the contraction induced by serotonin (10(-8) - 10(-5) M) or histamine (10(-8) - 10(-4) M) in isolated porcine coronary arteries in a non-competitive and concentration-dependent manner. The potency of this effect of pranidipine was almost similar to that of nifedipine. In anesthetized open-chest pigs with coronary artery occlusion, pranidipine at a dose of 10 micrograms/kg, i.v. lowered blood pressure and increased heart rate, peak dP/dt and % segment shortening of the non-ischemic zone before occlusion. Pranidipine inhibited the ST elevation of the electrocardiogram and the increase in left ventricular end-diastolic pressure during ischemia. These results suggest that pranidipine might relieve symptoms via inhibition of coronary spasm and reduce myocardial ischemia due to reduction of both preload (left ventricular end-diastolic pressure) and afterload (blood pressure).