Creation of a Metabolic Sink for Tryptophan Alters the Phenylpropanoid Pathway and the Susceptibility of Potato to Phytophthora infestans

The creation of artificial metabolic sinks in plants by genetic engineering of key branch points may have serious consequences for the metabolic pathways being modified. The introduction into potato of a gene encoding tryptophan decarboxylase (TDC) isolated from Catharanthus roseus drastically altered the balance of key substrate and product pools involved in the shikimate and phenylpropanoid pathways. Transgenic potato tubers expressing the TDC gene accumulated tryptamine, the immediate decarboxylation product of the TDC reaction. The redirection of tryptophan into tryptamine also resulted in a dramatic decrease in the levels of tryptophan, phenylalanine, and phenylalanine-derived phenolic compounds in transgenic tubers compared with nontransformed controls. In particular, wound-induced accumulation of chlorogenic acid, the major soluble phenolic ester in potato tubers, was found to be two- to threefold lower in transgenic tubers. Thus, the synthesis of polyphenolic compounds, such as lignin, was reduced due to the limited availability of phenolic monomers. Treatment of tuber discs with arachidonic acid, an elicitor of the defense response, led to a dramatic accumulation of soluble and cell wall-bound phenolics in tubers of untransformed potato plants but not in transgenic tubers. The transgenic tubers were also more susceptible to infection after inoculation with zoospores of Phytophthora infestans, which could be attributed to the modified cell wall of these plants. This study provides strong evidence that the synthesis and accumulation of phenolic compounds, including lignin, could be regulated by altering substrate availability through the introduction of a single gene outside the pathway involved in substrate supply. This study also indicates that phenolics, such as chlorogenic acid, play a critical role in defense responses of plants to fungal attack.

Increase in cystathionine content in rat liver mitochondria after D,L-propargylglycine administration

Intraperitoneal administration of D,L-propargylglycine to rats resulted in an increase in the cystathionine content of whole liver and liver mitochondria. Cystathionine in mitochondria was identified by amino acid analysis, thin layer chromatography, high-voltage paper electrophoresis and liquid chromatography-mass spectrometry. The cystathionine content of whole liver was 5.37 ± 1.59µmol per g of fresh liver at 14 h after the administration of 50 mg of D,L-propargylglycine per kg of body weight, while 0.07 ± 0.02µmol of cystathionine per g of fresh liver was detected in the control rats. The cystathionine content of liver mitochondria from both groups of rats was 9.40 ± 1.20 and 0.19 ± 0.04 nmol of cystathionine per mg of protein, respectively. The mitochondrial cystathionine increased dose-dependently with the increase of D,L-propargylglycine administered. The increase was proportional to the time after the administration up to 12 h, and then decreased. The increase of cystathionine in the liver mitochondria was linearly proportional to that in the whole liver. These results suggest that cystathionine in liver mitochondria is in an equilibrium with that in the cytosol.

[Management of hypopharyngeal and cervical esophageal cancer (HCEC): a comparative study of primary-surgical and primary-radiotherapeutic regimens]

The results of two treatment regimens for HCEC were compared. Surgery played a main role in the first regimen (Group A), in which patients underwent total pharyngo-laryngo-esophagectomy (with bilateral neck dissection and primary reconstruction by pectoralis major myocutaneous flap or gastric tube) after receiving 20 Gy of irradiation therapy. Chemotherapy was combined in some patients. In the second regimen (Group B), radiation was employed as the main treatment in order to conserve the larynx. Chemotherapy (UFT 300 to 600 mg/day; in some patients one or two courses of intra-venous cisplatinum therapy) was combined with radiation therapy (60 Gy) to improve the effectiveness of this regimen. In case of radiation failure, a salvage operation was performed. We investigated 60 HCEC patients who visited the Kitasato University Hospital during the period from 1983 to 1992. The tumor was located in the PC, PS, PW, and Ce areas in 3, 48, 5, and 4 patients, respectively. There were 25 cases in group A and 35 in group B. Five-year cumulative survival rates were 52% and 55%, respectively. In group B, tumor remained or recurred after the initial treatment in 13 patients. Three patients refused to receive salvage operation. Four of the 10 patients who received salvage operation became tumor free. The larynx preservation rate was 71% in group B. From the standpoint of improving QOL, the group B regimen is recommended.

Interactions of peroxyquinols with cytochromes P450 2B1, 3A1, and 3A5: influence of the apoprotein on heterolytic versus homolytic O-O bond cleavage

In studies of the mechanisms involved in oxygen activation by cytochromes P450 (P450s), organic hydroperoxides are frequently used to model the putative peroxyferrous complex formed immediately prior to oxygen-oxygen bond cleavage during the reaction cycle of this monooxygenase. Heterolysis of the O-O bond by ferric P450 generates the catalytically competent oxo-ferryl intermediate analogous to peroxidase Compound I, and homolysis produces the Compound II analog capable only of one-electron oxidations. As P450s have been shown to catalyze both modes of O-O bond scission, the present investigation was focused on the influence of the apoprotein on the relative contributions of these competing processes. Liver microsomes from rats treated with the P450-inducing agents phenobarbital, beta-naphthoflavone, and dexamethasone, as well as purified P450s 2B1, 3A1, and 3A5 were incubated with 2,6-di-tert-butyl-4-hydroperoxy-4-methyl-2, 5-cyclohexadienone (BHTOOH). Ratios of heterolysis to homolysis were determined by analyzing the products derived from this hydroperoxide. The data demonstrate that BHTOOH is cleaved with a ratio of approximately 1.0 with all of the liver microsomal or purified P450s investigated, except with liver microsomes from dexamethasone-treated rats or with P450s 3A1 and 3A5. In these cases, heterolysis predominated over homolysis by factors of 2.5 to 4.0. On the other hand, microsomes rich in P450 2B1 catalyzed predominantly heterolysis with analogs of BHTOOH containing smaller alkyl substituents. The data are consistent with a requirement for solvent access to the peroxyferrous complex and general acid catalysis of heterolytic O-O bond cleavage by water.

High-performance liquid chromatographic determination of taurine and hypotaurine using 3,5-dinitrobenzoyl chloride as derivatizing reagent

A method for the determination of taurine and hypotaurine in biological samples involving the preparation of their 3,5-dinitrobenzoyl derivatives followed by HPLC was established. Taurine and hypotaurine in aqueous media were reacted with 3,5-dinitrobenzoyl chloride in the presence of triethylamine to prepare 3,5-dinitrobenzoyl derivatives. These derivatives were separated on a C18 reversed-phase column and detected by recording the absorbance at 254 nm. Derivatives of taurine and hypotaurine were obtained in yields of 91.4 +/- 3.3 and 85.6 +/- 2.6%, respectively. The calibration graphs for taurine and hypotaurine were linear between 2.5 and 500 microM with correlation coefficients of 0.999. The method was applied to the determination of taurine and hypotaurine in human and rat urine and blood and in rat liver and heart.

Protective effects of KW-3902, a novel adenosine A1-receptor antagonist, against gentamicin-induced acute renal failure in rats

We investigated the possible renal protective effects of KW-3902 (8-(noradamantan-3-yl)-1,3-dipropylxanthine), an adenosine A1-receptor antagonist, against gentamicin (GM)-induced acute renal failure (ARF) in rats. ARF was induced by subcutaneous injection of GM at 80 mg/kg/day for 12 days. KW-3902 (0.001-0.1 mg/kg, p.o., twice daily) attenuated the increases of serum creatinine and urea nitrogen and the decrease of creatinine clearance in rats treated with GM. In contrast, furosemide and trichlormethiazide aggravated the GM-induced nephrotoxicity. These results suggest that KW-3902 can ameliorate the GM-induced ARF and that endogenous adenosine may be involved in GM-induced ARF via the adenosine A1-receptor.

[Small incision extra-capsular cataract extraction with a manual nucleus division technique and intraocular lens implantation]

A 6mm incision extra-capsular cataract extraction (ECCE) with a manual nucleus division technique and intraocular lens implantation was performed on 70 eyes of 66 patients with senile or complicated cataracts. Post-operatively, the visual acuities were 0.5 or better in 76.6% at one week and in 96.4% at three months. The mean post-operative astigmatism was 1.96 +/- 1.08D at one week and 0.92 +/- 0.68D at three months which was less than that in the control group, large incision (10-12mm) ECCE performed in the same period and compared at the same times, respectively (P < 0.001). The technique and instruments of this procedure were described, and its key steps and complications discussed.

Protective effects of benidipine against myocardial damage following ischemia and reperfusion in the isolated perfused rat heart

We investigated the possible protective effects of benidipine (Coniel), a calcium antagonist, on mechanical dysfunction, metabolic damage and changes in vascular reactivity during ischemia and reperfusion in the Langendorff-perfused rat heart. The responses of perfusion pressure to U-46619, a vasoconstrictor, and acetylcholine, an endothelial-dependent vasodilator, were also determined as indices of the vascular function. Thirty min of reperfusion following 30 min of global ischemia produced contractile failure and the marked release of lactate dehydrogenase (LDH) and creatine phosphokinase (CPK). Additionally, the ischemia and reperfusion augmented the vasoconstrictor response to U-46619, and depressed the endothelium-dependent vasodilator response to acetylcholine. These hearts were treated with 1 or 10 nM benidipine from 20 min before ischemia to the beginning of ischemia. While benidipine at 10 nM had a modest negative inotropic action, 1 nM of this drug had minimal depressant effects on the preischemic function. The depressed contractile function after the ischemia was improved, and the increased releases of LDH and CPK were significantly ameliorated by benidipine. Also, benidipine restored the augmented contractile response to U-46619 and preserved the vasodilator response to acetylcholine. These results demonstrate that pretreatment with benidipine prevents myocardial injury following ischemia and reperfusion. The cardioprotective effects of benidipine may in part be due to the protection of vascular reactivity by this drug.

Diuretic effects of KW-3902, a novel adenosine A1-receptor antagonist, in various models of acute renal failure in rats

Using various models of acute renal failure (ARF) in rats, the diuretic effects of 8-(noradamantan-3-yl)-1,3-dipropylxanthine (KW-3902), a novel adenosine A1-receptor antagonist (0.01 and 0.1 mg/kg, p.o.), were determined and compared with those of furosemide (30 mg/kg, p.o.) and trichlormethiazide (TCM; 1 mg/kg, p.o.). In cisplatin-induced ARF rats, KW-3902 and TCM, but not furosemide, increased Na excretion. KW-3902 did not affect creatinine clearance (CCRE), while TCM decreased CCRE. In gentamicin-induced ARF rats, KW-3902 increased urine volume (UV) and Na excretion. In glycerol-induced oliguric ARF rats, KW-3902, but not furosemide or TCM, increased UV, Na and K excretion and tended to improve the depressed CCRE, suggesting that the improvement of renal hemodynamics might also contribute to the diuretic effect of KW-3902. In glycerol-induced polyuric ARF rats, only KW-3902 significantly increased UV and Na excretion. These results demonstrate that KW-3902 induces natriuretic effects in various models of ARF and that the effect of KW-3902 is more prominent than those of furosemide and TCM. The present results suggest that endogenous adenosine may be involved in various forms of ARF via adenosine A1-receptors.

[Susceptibility of Anopheles gambiae to insecticides in the Ivory Coast]

Studies on the susceptibility of Anopheles gambiae to insecticides were carried out in rice field areas of Côte-d'Ivoire. An. gambiae larvae populations from Côte-d'Ivoire were resistant to DDT but susceptible to organophosphorous insecticides. Adult populations from the surroundings of Bouake were resistant to DDT and permethrin. Resistance to propoxur was strongly suspected. The knock-down effect of both deltamethrin and lambdacyhalothrin was delayed and strongly decreased. The control strain from Bobo-Dioulasso and populations from rice fields of Katiola located far from the city were still susceptible to the three pyrethroids. It is likely that resistance to pyrethroids in Bouake has been promoted by the intensive use of domestic aerosol sprays.

All-optical implementation of a self-organizing map: a preliminary approach

Optically addressed ferroelectric liquid-crystal devices present certain characteristics that make them attractive for all-optical implementations of neural architectures. This is particularly true for the implementation of analog self-organizing systems such as Kohonen's self-organizing map. The optical architecture proposed here is based on the principle of a resonator memory. The main novelty lies in the two-dimensional, continuous, binary information encoding and organization. Basic operations such as neural decision, weight updating, and information spatial ordering are investigated. The principle of a learning procedure close to the Hebbian rule is discussed.

Longitudinal changes of serum insulin concentration and insulin antibody features in persistent insulin autoimmune syndrome (Hirata's disease)

In a 56-year-old woman with granulomas of gold thioglucose in her hips, who developed insulin autoimmune syndrome, the relationships among the frequency or severity of hypoglycemic attacks, serum insulin (IRI) concentration, and characteristics of insulin antibodies were investigated during the clinical course with steroid treatment and two resection operations for the gold-thioglucose granulomas. When hypoglycemia was severe, the total IRI level was elevated, and Scatchard analysis showed that a high-affinity (k1), low-capacity (b1) population of antibodies had a relatively low affinity constant and very high binding capacity compared with the same population of antibodies in insulin-treated diabetic patients. When the attacks were relieved by steroid treatment and/or granuloma resection operation, the total IRI level was decreased and the high-affinity (k1), low-capacity (b1) population of antibodies showed a higher affinity constant and a lower binding capacity than those during the attacks. This indicated that the antibodies changed their characteristics to release insulin into the serum. The k1/b1 population of insulin antibodies with the lower affinity constant and higher binding capacity may easily release human insulin into the serum, leading to hypoglycemia. The longitudinal change of the k1/b1 population suggests a clonal change of the B cells producing the insulin antibody in insulin autoimmune syndrome.

[Carcinoma of the nasopharynx: analysis of treatment results in 51 patients]

The outcomes of 51 cases of nasopharyngeal carcinoma, treated in our hospital between July 1971 and June 1991, were evaluated. Factors which appeared to influence prognosis were assessed by the Kaplan-Meier method. The ages of the patients ranged from 18 to 74 years. There were 38 males and 13 females. The cumulative five-year survival rate for the whole study population was 60.6%. The UICC classification (1987) was used for disease staging. The percentages of patients surviving after five years were: 100% (n = 1) for stage II, 75% (n = 4) for stage III, and 58.1% (n = 46) stage IV. The histological type with the highest survival rate was poorly differentiated squamous cell carcinoma, which had a 69.8% (n = 37) survival rate. The anatomical sites of primary tumors were the lateral wall (62.4%, n = 33) and the posterior wall (54%, n = 33). Percentages of patients according to classification based on initial therapy were as follows: Combined radiotherapy and chemotherapy group, 61.5% (n = 22); radiotherapy alone group, 56.5% (n = 22). The incidences of local recurrence according to initial therapy were 36% in the combined therapy group and 50% for the radiotherapy alone group. There were no metastases to the cervical lymph nodes after initial therapy in stage II and III. In stage IV, the rate of metastasis was lower when combined therapy was given. When the relationship between initial therapy and distant metastasis was evaluated, the rate of metastasis was lower in the combined therapy group. We conclude that combined therapy is necessary in the treatment of nasopharyngeal carcinoma.(ABSTRACT TRUNCATED AT 250 WORDS)

Variable baseline gamma-glutamylcysteine synthetase messenger RNA expression in peripheral mononuclear cells of cancer patients, and its induction by buthionine sulfoximine treatment

The role of glutathione (GSH) in tumor cell resistance to alkylating agents and platinum compounds is suggested by a body of laboratory and clinical studies. The rate-limiting enzyme in GSH synthesis is gamma-glutamylcysteine synthetase (gamma-GCS), the expression of which is proportional both to GSH content and to the level of resistance in ovarian cancer cell lines. The role of this enzyme in regulating GSH levels is unclear, however. Reversal of resistance is achieved in vitro and in vivo with the use of buthionine sulfoximine (BSO), a potent inhibitor of gamma-GCS. In the course of a Phase I clinical trial of BSO and melphalan, we have measured GSH and expression of gamma-GCS mRNA in peripheral mononuclear cells before and at intervals after the initiation of treatment with BSO. Mean baseline GSH content was 6.89 nmol/mg protein. Treatment with BSO (10.5 to 17 g/m2 i.v. every 12 h for six doses) resulted in a mean nadir GSH decline to 19% of control values, most commonly on day 3. Baseline expression of gamma-GCS mRNA was measured by a reverse transcriptase polymerase chain reaction-based method. When described relative to that of beta-actin, the expression of gamma-GCS varied over 3-fold among individuals. Following GSH depletion by BSO, the level of gamma-GCS mRNA rose successively on days 3 and 5 to reach a mean increase of 2-fold on day 8. Differences were observed among patients in their capacity to respond to GSH depletion by increasing gamma-GCS steady-state mRNA levels (1.4- to 3.1-fold). These results show that the expression of gamma-GCS is variable in the population and suggest that the cellular content of GSH may be involved in the regulation of its expression.

Plasma membrane changes in the rat corpus luteum induced by oxygen radical generation

The luteolytic mechanism was investigated in rat corpora lutea (CL). This study focused on the changes that occur in the plasma membrane. Previous experiments with rat luteal cells indicated that in vitro generation of superoxide radicals by xanthine oxidase disrupted LH-stimulated cAMP production and progesterone secretion similar to the effect of prostaglandin F2 alpha, the luteolytic hormone. In the present study, we observed that xanthine oxidase treatment of plasma membrane samples from CL caused a large decrease in fluidity, which also occurs during prostaglandin F2 alpha-induced luteolysis. This fluidity change was blocked by catalase, bromophenacyl bromide, an inhibitor of phospholipase-A activity, indomethacin, and free radical scavengers, and it was reversed by removal of FFA from the membrane. In addition, xanthine oxidase treatment caused phospholipid breakdown, formation of neutral lipids, a burst of inorganic peroxides, and a sustained rise in the level of lipid peroxides. These results indicate that free radical generation causes several changes that disrupt the plasma membrane of CL cells, and they raise the possibility that phospholipid breakdown could be involved in the mechanism that inhibits LH stimulation of steroidogenesis during luteolysis.

Preparation and characterization of S-[2-carboxy-1-(1H-imidazol-4-yl)ethyl]glutathione and its derivatives as proposed precursors of S-[2-carboxy-1-(1H-imidazol-4-yl)ethyl]cysteine, a compound found in human urine

Formation of 3-[(carboxymethyl)thio]-3-(1H-imidazol-4-yl)propanoic acid (I) and S-[2-carboxy-1-(1H-imidazol-4-yl)ethyl]cysteine (II), compounds found in human urine, has been demonstrated by enzymatic degradation of S-[2-carboxy-1-(1H-imidazol-4-yl)ethyl]glutathione (III). Compound (III) was chemically synthesized in 72% yield by incubating the reaction mixture of trans-urocanic acid and 3-fold excess GSH at 65 degrees C for 1 wk, which was accompanied by formation of N-(S-[2-carboxy-1-(1H-imidazol-4-yl)ethyl]cysteinyl)glycine (IV) in 15% yield. S-[2-Carboxy-1-(1H-imidazol-4-yl)ethyl]-N-gamma-glutamylcysteine (V) was produced by partial hydrolysis of compound (III) in HCl. The synthesized compounds were characterized mainly by fast-atom bombardment mass spectrometry and high-voltage paper electrophoresis as well as chemical degradation. Incubation of compound (III) with rat kidney homogenate in a Tris buffer (pH 8), formed compound (II) in 80% yield possibly via compound (IV). Yield of compound (II) was increased by adding glycylglycine to the reaction mixture. However, little degradation of compound (III) occurred in the use of rat liver, brain, heart or spleen homogenate as the enzyme source. Compound (II) was further metabolized to compound (I) by incubation with rat kidney homogenate in a phosphate buffer of pH 7.4. From these results, we suggest that the urinary compounds are products of enzymatic degradation of compound (III) and that GSH may participate in the metabolism of urocanic acid, the first catabolite of L-histidine.

Enrichment of proteinase activity in deteriosomes, a new class of microvesicles

Non-sedimentable microvesicles, termed deteriosomes, have been isolated from the cytosol of bean cotyledons by ultrafiltration, and found to be enzymatically active. Specifically, they possess proteinase activity that is able to catabolize exogenous proteins as well as deteriosome proteins. The proteolytic activity is inhibited by heat-denaturation and known proteinase inhibitors (iodoacetate and phenylmethylsulfonyl fluoride), and the pattern of deteriosome-associated proteinase activity changes with advancing senescence of the cotyledon tissue. Deteriosomes are formed by blebbing from membranes. The finding that they possess proteinase activity is consistent with an earlier proposal [(1991) Proc. Natl. Acad. Sci. USA 88, 2269-2273] that they are involved in membrane turnover and serve as a vehicle for moving bilayer-destabilizing phospholipid and protein catabolites out of membranes into the cytosol for further processing. The data also indicate that a significant proportion of the proteinase activity traditionally considered to be cytosolic is associated with deteriosomes.

Isolation and characterization of deteriosomes from rat liver

Deteriosomes, a new class of microvesicles, have been isolated from rat liver tissue. These microvesicles are similar to those isolated previously from plant tissue [Yao et al., Proc Natl Acad Sci USA 88:2269-2273, 1991] in that they are nonsedimentable and enriched in membrane catabolites, particularly products of phospholipid degradation. Liver deteriosomes range in size from 0.05 microns to 0.11 microns in radius. They are also much more permeable than microsomal membrane vesicles indicating that the deteriosome bilayer is perturbed. The data are consistent with the proposal that deteriosomes are formed from membranes by microvesiculation and that they represent an intermediate stage of membrane deterioration. Furthermore, liver deteriosomes were found to contain phospholipase A2 activity. This suggests that they not only serve as a means of moving destabilizing macromolecular catabolites out of membranes into the cytosol but also possess enzymatic activity. The fact that the specific activity of phospholipase A2 is higher in deteriosomes than in deteriosome-free cytosol suggests that some of the enzymatic activity traditionally assumed to be cytosolic may in fact be associated with deteriosomes.

Cumene hydroperoxide-mediated inactivation of cytochrome P450 2B1. Identification of an active site heme-modified peptide

Cumene hydroperoxide (CuOOH)-mediated inactivation of cytochromes P450 (P450) results in the degradation of their prosthetic heme to products that alkylate the apoprotein. Indirect approaches suggest that this alkylation occurs at the active site. in order to identify the specific apoprotein site(s) alkylated, purified 3H- or 14C-heme-labeled P450 2B1 was incubated with CuOOH and subjected to lysyl endopeptidase-C digestion. Two major peaks (L1 and L2) containing 3H- or 14C-labeled peptides were detected by reverse-phase high pressure liquid chromatography of the digest. L1 contained the highest specific radioactivity and after Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis yielded 3 peptide bands (M(r) approximately 3,500 (P1), 5,000 (P2), and 7,000 (P3)). Although all 3 bands were found radiolabeled, the yield of P1 was higher than that of P2 or P3. Amino acid sequence analysis of the first 13 N-terminal residues of P1 revealed the sequence RICLGEGIARNEL, corresponding to residues 434-446 of the reported 2B1 sequence. A species with the molecular mass of 3771 +/- 1 Da was detected in preliminary electrospray mass spectrometric analysis of L1. Since the theoretical average mass of the predicted peptide (residues 434-466) is 3721.99 Da, the additional 49 +/- 1 Da are considered to be contributed by the alkylating heme fragment. This alkylated 2B1 sequence contains not only Cys436, the conserved residue that provides the SH ligand for heme, but also other highly conserved residues, and therefore corresponds to the heme-sandwiching helix L of P450cam. To our knowledge, this is the first report to localize CuOOH-induced heme alkylation of 2B1 to its active site.

[Influence of cataract on automated perimetry]

58 eyes of 58 patients underwent cataract surgery with IOL implantation. The density of cataract was quantified by the Opacity Lensmeter 701 before operation and the visual field by program G1 of Octopus 201 before and after operation. The visual fields showed that there was significant difference in the mean defect (MD) before and after operation, but not in the corrected loss variance (CLV), indicating that cataract only caused diffuse visual field damage. This was also confirmed by the parallel shift of the mean cumulative defect curve after surgery. The preoperative lens opacity reading and the visual acuity were correlated with the difference between the pre- and post-operative MD, showing that measurement of OLM 701 and visual acuity permitted assessment of the influence of cataract on the visual field.

Malignant tumors of the head and neck in young patients

Ten patients under 20 years of age, with malignant tumors of the head and neck was treated at the Department of Otorhinolaryngology of Kitasato University Hospital from August 1971 to December 1989. The primary lesions were situated in the nose and paranasal sinuses in 3, middle ear in 2, epipharynx in 2, and parapharynx, esophagus, and neck in 1 patient. Histological examination indicated 3 rhabdomyosarcomas, 2 malignant lymphomas, and 1 each of neuroblastoma, malignant neuroendocrine tumor, transitional cell carcinoma, lymphepithelioma, and squamous cell carcinoma. The sites of origin and histopathology of malignant tumors in such patients usually differ from those in adults. Well differentiated squamous cell carcinoma of head and neck is common in adults but not in children, in whom non-epithelial malignant tumors or sarcomas are not rare. Radiotherapy is more effective for treating malignant tumors of the head and neck in young than in adults. Eight of 10 patients are still alive, 7 of whom for 5 years or more. Two with rhabdomyosarcoma died.

Assay of sialidase activity using ion-exchange chromatography and acidic ninhydrin reaction

A new assay method for sialidase (EC 3.2.1.18) activity using ion-exchange chromatography and acidic ninhydrin reaction has been developed. Fetuin, 4-methylumbelliferyl-N-acetylneuraminic acid (MUB-NANA), gangliosides and N-acetylneuramin-lactose were examined as substrates. Free sialic acid liberated from these substrates by sialidase reaction was isolated with a Dowex 1-X8 column (trifluoroacetate form, 1.5 cm x 0.5 cm I.D.) and determined by acidic ninhydrin reaction. Among the substrates tested, MUB-NANA was the best in the present method, N-Acetylneuramin-lactose could not be used as the substrate, because it was not separated from liberated sialic acid under the conditions used. The recovery of N-acetylneuraminic acid was above 88%, and the sensitivity of the method was 20 nmol in 300 microliters of the reaction mixture. The method was applied to the sialidase assay during its purification from rat skeletal muscle, and a Michaelis constant of 1.15 mM was obtained with MUB-NANA as the substrate. The method using the acidic ninhydrin reaction was simple and exhibited good reproducibility.

Hemodynamic observation and treatment approach for patients with angina decubitus

In order to investigate the mechanism and treatment of angina decubitus, 20 patients (18 men and 2 women aged 36-70 years) were studied during hospitalization. All patients were found to have an increased heart rate x systolic blood pressure product before the onset of angina decubitus, indicating that this type of angina pectoris belongs to the category of effort angina. Of the 11 patients investigated by continuous hemodynamic monitoring, 3 had significant progressive increases in pulmonary artery systolic pressure (PASP) and pulmonary artery diastolic pressure (PADP) before onset: their episodes of angina could not be completely controlled by digoxin and diuretics, but quickly subsided after beta blockers were added. Among the other 8 patients, PADP increased slightly in 5 and remained unchanged in 3 cases before onset: these patients had no manifestations of LV dysfunction, and beta blockers combined with coronary vasodilators produced satisfactory effects. These results indicate that LV failure is not a major factor in the pathogenesis of angina decubitus. The LV diastolic dysfunction seen in 8/11 cases may have been related to LV hypertrophy caused by long-term hypertension or chronic persistent ischemia.

Differential apoprotein loss of rat liver cytochromes P450 after their inactivation by 3,5-dicarbethoxy-2,6-dimethyl-4-ethyl-1,4-dihydropyridine: a case for distinct proteolytic mechanisms?

Suicide inactivation of hepatic cytochrome P450 (P450) enzymes 2C11, 2C6, and 3A1/A2 by 3,5-dicarbethoxy-2,6-dimethyl-4-ethyl-1,4-dihydropyridine (DDEP) in intact rats results in prosthetic heme destruction, albeit by apparently distinct mechanisms. Such heme destruction is now shown to be associated with the loss of immunochemically detectable apoprotein of P450s 2C11 and 3A but with little of that of P450 2C6, in spite of their comparable DDEP-mediated functional inactivation. The loss of a approximately 50-kDa hepatic microsomal protein band along with the immunoreactive P450 3A loss strengthens the concept that such an in vivo loss indeed reflects proteolysis of the DDEP-inactivated P450. Furthermore, this propensity of DDEP-inactivated P450s 3A for proteolysis appears to correlate with the relative degree of prosthetic heme alkylation of their apoprotein rather than their functional inactivation per se. Thus, rapid degradation of apoP450s 3A was seen after DDEP treatment, which promoted extensive irreversible heme binding to apoP450s 3A, but not after exposure to allylisopropylacetamide (AIA), which inactivates these isozymes comparably, but induced minimal apoP450 3A heme alkylation. In addition, differences were observed in the relative sensitivities of proteolysis of DDEP-inactivated P450s 2C11 and 3A to hemin, which largely prevented the DDEP-induced proteolytic loss of P450 2C11 but apparently failed to prevent the loss of DDEP-inactivated P450s 3A, when coadministered with DDEP. This differential hemin sensitivity of the proteolysis of DDEP-inactivated P450 2C11, coupled with the observation that immunochemically detectable P450 2C11 loss occurs after its inactivation by both AIA and DDEP, provides compelling support for the existence of distinct proteolytic pathways for individual suicidally inactivated P450s.

Isolation of S-[2-carboxy-1-(1H-imidazol-4-yl)ethyl]cysteine from human urine

S-[2-Carboxy-1-(1H-imidazol-4-yl)ethyl]cysteine (I), a proposed precursor of 3-[(carboxymethyl)thio]-3-(1H-imidazol-4-yl)propanoic acid [Kinuta, Yao, Masuoka, Ohta, Teraoka & Ubuka (1991) Biochem. J. 275, 617-721], was isolated from healthy human urine by using ion-exchange column chromatography. Identification of the isolated compound with compound (I) was performed by physicochemical analyses involving i.r., m.s. and n.m.r. spectrometries as well as high-voltage paper electrophoresis, t.l.c. and paper chromatography. Compound (I) was synthesized in 80% yield by incubation of a reaction mixture containing trans-urocanic acid and 3-fold excess of cysteine at 70-75 degrees C. From these results we suggest that natural thiol compounds such as cysteine and GSH participate in the metabolism of urocanic acid, a key metabolite of L-histidine.

Human insulin-specific immunoglobulin G antibody and hypoglycemic attacks after the injection of gold thioglucose

A 56-year-old woman with granulomas of gold thioglucose in her hips exhibited recurrent bouts of hypoglycemic attacks. The first attack occurred 2 years after the last injection of gold thioglucose, when large amounts of extractable insulin and human insulin-specific antibody were noted in her serum. Histological examination of the resected granulomas showed marked infiltration of lymphocytes, plasma cells, and macrophages containing yellowish-brown granules, which proved to be gold by electron microscopy using X-ray microanalysis. After resection of the granuloma, however, the frequency of the hypoglycemic attacks decreased remarkably as well as the levels of both extractable insulin and human insulin-specific antibody.

[Study of pyogenic granuloma of the oral cavity]

Pyogenic granuloma is one of the diseases sometimes seen in otorhinolaryngology clinics. The clinical features of this disease are understood to be that the lesion is located in the oral cavity in the majority of cases that its causative agent is usually discovered and that it most likely grows as a malignant tumor. However, the entity of pathological diagnosis has not been established. Thirty-one cases of oral pyogenic granuloma, including 16 males and 15 females, are reported in this paper. The granuloma was located most frequently at the tongue, followed, in order, by the gingiva, buccal mucosa, hard palate, lip and oral floor. The period between the patient's first visit to our clinic and the onset of his/her complaint was variable. It was relatively shorter in those cases with the lesion at the gingiva or tongue as compared to other locations. The size of the lesion was smaller than 10 x 10 mm. We classified the pathological features into three patterns; granuloma type, hemangioma type, and intermediate type. Many cases of lesions located at the back of the tongue, buccal mucosa, or hard palate were of the hemangioma type, while many cases of lesions located at the top of the tongue, gingiva, or oral floor were of the granuloma type. We have the impression that pyogenic granuloma could be one of the purulent changes associated with benign oral tumors.

[A comparative study between the clinical and autoptic findings in cases with malignant tumor in the head and neck]

In 106 autopsies of patients in Kitasato University Hospital from 1974 to 1989, who had died of malignant tumor in the head and neck, the relationship between the clinical diagnosis and its autoptic finding was retrospectively investigated. The result was summarized as follows. 1. Characteristics in 98 cases other than malignant lymphoma: 1) Local recurrence was detected by autopsy in 60 cases (61%) among 98. Discrepancy between clinical diagnosis and autoptic findings was recognized in 10 cases (10%), in whom 4 false positive cases by clinical diagnosis were included and it was considered that the rate was relatively high. 2) The metastatic lymph nodes were demonstrated by autopsy in 50 cases (51%). Discrepancy between clinical diagnosis and autoptic findings was found in 37 (38%), 35 of them were clinically diagnosed to be negative. However, in 35 of them it was considered that the discrepancy had not influenced their fatal courses. 3) Metastases to distant organs were demonstrated by autopsy in 49 (50%). Discrepancy between clinical diagnosis and autoptic findings was found in 39 (40%). 33 of them were clinically diagnosed to be negative. The discrepancy concerned with the causes of death was shown in 5 cases. 2. Characteristics in 8 cases of malignant lymphoma: Discrepancy between clinical diagnosis and autoptic findings of distant metastases was frequently observed but the discrepancy concerned with the causes of death was not shown. There were 2 cases in which side effect of chemotherapy may cause poor prognosis.

Nonsedimentable microvesicles from senescing bean cotyledons contain gel phase-forming phospholipid degradation products

A mixture of liquid-crystalline and gel-phase lipid domains is detectable by wide angle x-ray diffraction in smooth microsomal membranes isolated from senescent 7-day-old cotyledons, whereas corresponding membranes from young 2-day-old cotyledons are exclusively liquid-crystalline. The gel-phase domains in the senescent membranes comprise phospholipid degradation products including diacylglycerols, free fatty acids, long-chain aldehydes, and long-chain hydrocarbons. The same complement of phospholipid degradation products is also present in nonsedimentable microvesicles isolated from senescent 7-day-old cotyledons by filtration of a 250,000g, 12-hour supernatant through a 300,000 dalton cut-off filter. The phospholipid degradation products in the microvesicles form gel-phase lipid domains when reconstituted into phospholipid liposomes. Nonsedimentable microvesicles of a similar size, which are again enriched in the same gel-phase-forming phospholipid degradation products, are also generated in vitro from smooth microsomal membranes isolated from 2-day-old cotyledons when Ca(2+) is added to activate membrane-associated lipolytic enzymes. The Ca(2+)-treated membranes do not contain detectable gel-phase domains, suggesting that the phospholipid degradation products are completely removed by microvesiculation. The observations collectively indicate that these nonsedimentable microvesicles serve as a vehicle for moving phospholipid degradation products out of membrane bilayers into the cytosol. As noted previously (Yao K, Paliyath G, Humphrey RW, Hallett FR, Thompson JE [1991] Proc Natl Acad Sci USA 88: 2269-2273), the term "deteriosome" connotes this putative function and would serve to distinguish these microvesicles from other cytoplasmic microvesicles unrelated to deterioration.

Intravenous recombinant tissue-type plasminogen activator in acute myocardial infarction

The efficacy and safety of intravenously administered recombinant tissue-type plasminogen activator (rt-PA, Boehringer Ingelheim Corp.) was investigated in 10 patients with acute myocardial infarction (AMI). rt-PA was given as a 10 mg bolus dose followed by infusions of 50 mg, 20 mg and 20 mg in three successive hours. All patients underwent baseline coronary angiography before thrombolytic therapy. Ninety minutes after the initiation of rt-PA infusion, recanalization of infarct-related coronary arteries as confirmed by angiography was achieved in 7 patients. The largest reduction in circulating fibrinogen was observed 4 to 6 h after the start of rt-PA infusion--14.3%. Moderate hemorrhage at the sites of arterial puncture occurred in 2 cases, probably as a result of heparin anticoagulation. No other side effects occurred. So rt-PA is an effective and safe thrombolytic agent.

Secondary prevention of myocardial reinfarction with low dose aspirin

A clinical trial of secondary prevention of reinfarction with low dose aspirin is reported. 50 mg aspirin per day was administered in 216 case. 211 cases did not take aspirin or any other antiplatelet agents as a control group. The follow-up periods in the two groups were 19.4 +/- 12.6 mon and 20.7 +/- 13.0 mon, respectively. There were 175 males in the aspirin group and 137 males in the control group. The incidence of reinfarction was reduced by 65% and platelet aggregation was inhibited obviously in the aspirin group as compared to the control group in men, whereas no significant trends were observed in women.

Sternal wound infections and use of internal mammary artery grafts

Previous studies have provided conflicting evidence as to whether an increased risk of mediastinitis is associated with use of the internal mammary artery as a coronary bypass graft. In this study the effects of internal mammary artery grafts on wound complications were analyzed in a prospective, nonrandomized fashion. At New York University Medical Center from January 1985 through May 1988, 2356 patients underwent isolated coronary revascularization. Among these patients 1394 received one or more internal mammary artery grafts (group I) and 962 had vein grafts only (group II). Group I had a mean age of 59.5 years versus 67.7 years in group II; diabetes was equally present in both groups (22.7% versus 24.7%). Operative mortality rate was 1.3% in group I and 5.6% in group II. Sternal infection was significantly more prevalent in group I (2.2%, 31/1394) than in group II (0.8%, 8/962). Multivariate analysis revealed that aortic crossclamp time, use of a single internal mammary artery graft, use of a double mammary graft, and diabetes were associated with increased risk of sternal infection. The use of bilateral internal mammary artery grafting doubled the odds ratio of the risk compared with use of a single mammary graft, and the combination of diabetes and double internal mammary artery grafts increased the odds ratio 13.9-fold. Patients with an internal mammary artery graft who had sternal infection had a longer period of hospitalization than patients without a mammary artery graft who had sternal infection. We conclude that the risk of sternal infection is increased by the use of an internal mammary artery graft, especially use of double mammary grafts in the presence of diabetes.

Endothelium-dependent regulation of vascular tone of the porcine ophthalmic artery

The endothelium produces relaxing and contracting substances, among them nitric oxide and endothelin. The role of the endothelium was investigated in the regulation of vascular tone in isolated porcine ophthalmic arteries suspended in a myograph system for isometric tension recording. In quiescent arteries with endothelium, the inhibitor of nitric oxide formation from L-arginine, L-NG-monomethyl arginine (L-NMMA), evoked endothelium-dependent contractions which were reversed by L-, but not D-arginine. In arteries contracted with serotonin, bradykinin evoked potent endothelium-dependent relaxations; L-NMMA markedly reduced the sensitivity but not the maximal response. Acetylcholine caused relaxations in preparations with endothelium but contractions in those without endothelium; L-NMMA prevented the relaxations and unmasked the contractions. The relaxations to the nitrovasodilator SIN-1 were more pronounced in preparations without than with endothelium. In quiescent arteries, quick stretching evoked endothelium-dependent contractions which were prevented by indomethacin. Endothelin-1, serotonin, and norepinephrine evoked concentration-dependent contractions with pD2 values of 8.1 +/- 0.1, 6.9 +/- 0.1, and 5.9 +/- 0.1, respectively. Removal of the endothelium markedly augmented the contractions induced by serotonin but not endothelin and norepinephrine. Thus, the endothelium profoundly affects vascular tone of the porcine ophthalmic artery. Endothelium-derived nitric oxide is released both under basal conditions and after stimulation with acetylcholine and bradykinin. It may play an important protective role in the circulation against vasospasm.(ABSTRACT TRUNCATED AT 250 WORDS)

Isolation and characterization of 3-[(carboxymethyl)thio]-3-(1H-imidazol-4-yl)propanoic acid from human urine and preparation of its proposed precursor, S-[2-carboxy-1-(1H-imidazol-4-yl)ethyl]cysteine

3-[(Carboxymethyl)thio]-3-(1H-imidazol-4-yl)propanoic acid (I) was isolated from healthy human urine by using ion-exchange column chromatography, and characterized by physicochemical analyses involving i.r., m.s. and n.m.r. spectrometries as well as chemical synthesis. The urinary content was 0.04-0.07 mumol/l. Compound (I) was synthesized by the addition of mercaptoacetic acid to urocanic acid. In order to establish the origin of the compound. S-[2-carboxy-1-(1H-imidazol-4-yl)ethyl]cysteine (II) and S-[2-carboxy-1-(1H-imidazol-4-yl)ethyl]glutathione (III) were produced by similar reactions of urocanic acid with cysteine and GSH respectively. The yield of compound (II) was markedly increased by sunlight irradiation of the reaction mixture or by the use of cis-urocanic acid rather than the trans isomer. Incubation of compound (II) with rat liver homogenate in a phosphate buffer, pH 7.40, formed a major and some minor products of enzymic degradation, one of which was identified with compound (I). Exposure of rats to the sunlight for 2 days resulted in increase of the epidermal content of trans-urocanic acid from the normal value of 0.38 to 1.70 micrograms/mg wet wt. of skin, accompanied by formation de novo of the epidermal cis isomer. After sunlight irradiation, the content of the trans isomer decreased at a constant rate of 0.03 micrograms/mg wet wt. of skin per day, whereas the cis isomer was eliminated more quickly, having a phase of rapid decrease in the early period. From these results we suggest that compound (I) may participate in the metabolism of urocanic acid and natural thiol compounds such as cysteine and GSH.

Identification and characterization of nonsedimentable lipid-protein microvesicles

Previously uncharacterized lipid-protein microvesicles have been isolated from young and senescing bean cotyledon tissue. The microvesicles are nonsedimentable and enriched in phospholipid degradation products (free fatty acids, long-chain aldehydes, and long-chain hydrocarbons). They range from 70 to 170 nm (radius) with a mean radius of 132 nm, and it is clear from freeze-fracture electron micrographs that they are bilayered in nature. Nonsedimentable lipid-protein microvesicles containing the same products of phospholipid degradation but smaller were also formed in vitro when smooth microsomal membranes from young cotyledon tissue were treated with Ca2+ to stimulate enzymatic degradation of phospholipids. The data suggest that these microvesicles comprise an intermediate stage of membrane lipid deterioration. They appear to serve as a vehicle for moving phospholipid degradation products out of membranes into the cytosol during senescence and perhaps also during normal membrane lipid turnover.

Presence of specific growth hormone binding sites in rainbow trout (Oncorhynchus mykiss) tissues: characterization of the hepatic receptor

The present work outlines the presence of specific binding for chinook salmon growth hormone (sGH) in different tissue preparations of rainbow trout. Optimal incubation conditions (pH, Tris, MgCl2) were determined. Specific binding was very sensitive to salt concentration during incubation. The specific binding reached a plateau after 15 and 25 hr of incubation at 12 and 4 degrees. At 20 degrees, specific and nonspecific binding were not stable. Specific binding dissociation was slower than association and was only partial. The binding was saturable (Bmax = 187 +/- 167 pmol), of high affinity (Ka = 2.4 +/- 0.8 10(9) M-1), and very specific for GH, properties which are in agreement with the characteristics of hormonal receptors. Sea bream and mammalian GH appeared 2- and 30-fold, respectively, less potent than cold sGH2 for displacing 125I-sGH2. Tissue preparations from ovary, testis, fat, skin, cartilage, gill, blood pellet, brain, spleen, kidney, and muscle showed significant saturable binding.

Influences of cigarette smoke inhalation on pharmacokinetics of cimetidine in rats

The influences of cigarette smoke inhalation on the pharmacokinetics of cimetidine administered orally and parenterally were investigated in rats using a smoking machine. The animals were exposed to two kinds of cigarette smoke, low- or high-nicotine.tar, inhaled for 10 min immediately after oral (50 mg/kg), intraperitoneal (25 mg/kg) or intravenous (10 mg/kg) administration of cimetidine. The plasma level after cimetidine was administered orally was lower in the absorption phase in the two cigarette smoke inhaling groups than in the non-smoking control group, and was particularly marked in the high-nicotine.tar cigarette smoke inhaling group. In contrast, no significant difference was found in cimetidine plasma level between the cigarette smoke inhaling groups and the non-smoking control group when administered intraperitoneally or intravenously. These results suggest that cigarette smoke inhalation may cause a suppression or a delay in cimetidine absorption from the gastrointestinal tract, and that the degree of influence is dependent upon the content of nicotine.tar in the cigarette smoke.

Expression of the Epstein-Barr virus genome in a nasopharyngeal carcinoma epithelial tumor cell line

An epithelial tumor cell line was recently established from a biopsy specimen of a nasopharyngeal carcinoma (NPC), and designated HONE-I. Uncloned (parental) HONE-I and HONE-I clone (C)-40 cells were found to contain latent Epstein-Barr virus (EBV). Expression of the latent EBV genome in HONE-I C-40 cells has been examined. It was possible to detect a small percentage of cells spontaneously synthesizing EBV early antigen (EA) and virus capsid antigen (VCA) by immunofluorescence (IF). In addition, the EBV nuclear antigens (EBNA-I and EBNA-2), as well as the EBV latent membrane protein (LMP) were detected in the HONE-I cells. Attempts were made to induce the latent EBV genome in these cells with iododeoxyuridine (IUdR). We observed a significant increase in the number of EA/VCA-positive cells, an increase in EBV DNA, the synthesis of virus particles, and the rescue of infectious virus after treatment of HONE-I C-40 cells with IUdR. The HONE-I C-40 cells should facilitate studies of the expression and regulation of the EBV genome in NPC epithelial tumor cells, which have not previously been available.

Effect of water isolation and early finishing on hardness of glass ionomer cements

Glass ionomer cements have the disadvantage of being vulnerable to moisture. We would like to overcome this problem by clinical procedures. Three glass ionomer cements were tested in vitro with the goal of protecting these materials from moisture during clinical operations. To observe the effectiveness of various surface protective measures, we divided each cement sample into six groups, each of which underwent 24-hour surface treatment. The first group was a control where the cement was covered with a glass slab for 24 hours. The remaining five groups were subjected to no treatment or treatment with varnish, cocoa butter, Teethmate-A, or Ketac-Glaze. Two additional groups were prepared for comparison of early finishing with and without water spray. When the Vickers hardness number (HVN) for each sample was measured at 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, and 40 days, it tended to increase after 24 hours, reaching a maximum value at different times with different cements. Analysis of variance revealed that during the first few days the hardness of the control was significantly different from that without treatment or with treatment by varnish or cocoa butter. However, treatment with Teethmate-A or Ketac-Glaze produced results close to those for the control. Significant differences in hardness during the first few days were noted when early finishing was carried out under wet and dry conditions. These findings indicate that a light-cured unfilled resin should be applied to the surface of glass ionomer cement immediately after the initial set to allow complete setting without interference by oral fluids. Also, water spray should be avoided during contouring of the cements if they have not fully hardened.

[Investigation of UFT and radiation combination therapy of head and neck cancer--mainly in laryngeal cancer]

We studied the effects of simultaneous combination therapy with UFT and radiation for 69 head and neck cases with the same protocol in 6 universities in Kanagawa. Completed cases (cases in which therapeutic effects could be evaluated) totaled 67 patients who could receive more than 40 Gy as a given radiation dose and more than 8.4 g as a total UFT dose. Responder rate at 90th day after completion of radiation in 67 completed cases (CR 57 cases + PR 6 cases/67 cases) was as favorable as 94%. A comparison between 52 cases of the most frequent laryngeal cancer and historical control 113 cases received single radiation therapy by means of Kaplan-Meier method resulted significantly (P less than 0.05) favorable in UFT combination group as for disease free rate in all cases, disease free rate in Stage IV cases, disease free rate in glottic cancer, and survival rate and disease free rate in supraglottic cancer. No severe adverse reactions were observed in all cases. This combination therapy with radiation and UFT was judged effective for head and neck cancer, especially laryngeal cancer.