Analysis of the non-sense mutants of varicella-zoster virus thymidine kinase

Summary.  Three non-sense mutants of varicella-zoster virus (VZV) thymidine kinase (TK) gene, VZTK₃₂₅, VZTK₂₇₈ and VZTK₂₂₄, were isolated. The mutants had a single nucleotide substitution at codons 326, 279 and 225, which changed the codon of TGG (tryptophan) to the stop codon TGA. The wild type (WT) and mutant TKs were expressed in E. coli cells and their characteristics were evaluated. VZTK₂₂₄ lost TK activity, but VZTK₃₂₅ and VZTK₂₇₈ maintained 74.8% and 21.2% of the WT TK activity. On the other hand, all mutants lost the thymidylate kinase activity. Moreover, VZTK₃₂₅ and VZTK₂₇₈ polypeptides were heat-labile. These data suggest that the carboxy-terminal portion of herpesvirus TK plays an important role in the stable folding of TK and thymidylate kinase activity. Received April 21, 1997 Accepted June 16, 1997     

Responses of isolated canine ophthalmic and ciliary arteries to vasoactive substances

The effects of 11 vasoactive substances were compared on the isolated and perfused canine internal and external ophthalmic and ciliary arteries. The vessels were isolated with the optic nerve, and perfused independently with Tyrode solution under a constant flow rate at 37 degrees C and a perfusion pressure of 40-80 mmHg. Drugs used were 5-hydroxytryptamine (5-HT), epinephrine (EPI), norepinephrine (NE), phenylephrine (PHE), prostaglandin F2 alpha (PGF2 alpha), ATP, dopamine (DA), tyramine (TYR), KCl, xylazine (XYL) and clonidine (CLO). Each drug solution was administered by a microinjector into the endothelial side of an artery through a cannula. Responses were obtained as changes in perfusion pressure. Results were as follows: 1) The rank order of potency for inducing a vasoconstriction in external ophthalmic arteries (EOA) was 5-HT greater than or equal to EPI greater than NE greater than PHE much greater than ATP greater than or equal to DA greater than KCl much much greater than TYR, XYL, CLO. Since PGF2 alpha induced only a slight vasoconstriction, it was omitted from the order. 2) In internal ophthalmic arteries (IOA), the responses were similar to those in EOA, although EPI, NE and PHE induced a relatively smaller response. The order was 5-HT greater than EPI = NE greater than PHE much greater than DA = ATP greater than KCl much much greater than TYR, XYL, CLO. 3) In ciliary arteries, the order was EPI greater than NE greater than PHE greater than PGF2 alpha greater than DA greater than ATP greater than KCl much much greater than TYR, XYL, CLO. It was found that 5-HT induced a slight vasoconstriction and the efficacy was low. PGF2 alpha induced a greater response in ciliary arteries than in EOA or IOA. 4) In all three arteries, alpha-2 adrenoceptor agonists, XYL and CLO did not produce significant changes in perfusion pressure. These three arteries might be rich in alpha-1 adrenoceptors but poor in alpha-2 adrenoceptors.     

Clinical evaluation of cefmenoxime in internal medicine, with special reference to infection associated with hematological disorders

Clinical evaluation of cefmenoxime (CMX, Bestcall) was performed against infections associated with hematological, respiratory tract and other disorders. Clinical effectiveness of CMX against severe infections with hematological disorders including sepsis, pneumonia, pyelitis and so on was 74.4% for good responses and against the respiratory tract infections, 96.2% for good responses was obtained. Neither objective or subjective side effects nor extreme abnormalities in laboratory tests were observed in these patients. It can be concluded, therefore, that CMX is one of the most useful drugs against infectious diseases associated with hematological disorders, respiratory tract and other disorders.     

Inhibition of erythrocyte 5-aminolaevulinate hydrolase activity by tin and its prevention by selenite.

Mice were injected with either SnCl2 (intraperitoneal) or Na2SeO3 (subcutaneous) alone or together at doses of 50 mumol/kg body weight. After 20 hours blood was collected and the concentrations of tin (Sn) and Selenium (Se) and the activity of 5-aminolaevulinate hydrolyase (ALA dehydratase, EC 4.2.1.24) in blood were determined. The concentrations of Sn in whole blood were 4.9 (SD 1.5) nmol/ml (n = 4) and ALA dehydratase activity was 10% of the control in Sn treated animals. Concentrations of Sn were 2.6 (SD 0.6) nmol/ml and ALA dehydratase activity was 92% of that in control animals when Sn and Se were simultaneously injected. The supernatant from lysed erythrocytes from Sn treated mice were applied to a Sephacryl S-300 column. The predominant peak containing Sn was eluted at the position of haemoglobin; a second peak was eluted at the position of ALA dehydratase. When the supernatant of lysed erythrocytes from mice injected with Sn and Se was chromatographed, a negligible amount of Sn was detected in the ALA dehydratase fraction. It thus appears that Sn binds to ALA dehydratase molecules and inhibits enzyme activity, and that simultaneous injection of Se prevents Sn binding to ALA dehydratase, thereby preventing the inhibition of ALA dehydratase activity by Sn.     

A case of immunohistochemically carcinoembryonic antigen producing cervical cancer--the evaluation of plasma CEA levels in 201 patients with uterine cancer

A case of a cervical cancer in a 40-year-old woman with a plasma carcinoembryonic antigen (CEA) level of 29.4 ng/ml was investigated using light and electron microscopy. In addition, the plasma CEA levels before treatment were determined in 168 patients with cervical cancer and in 33 patients with endometrial cancer. CEA was found to be elevated in the plasma of 19% of those with cervical cancer and in 6% of those with endometrial cancer. Effective serial plasma CEA determinations following therapy, in patients whose plasma or tumors initially contain elevated amounts of antigen, might be useful as an adjunctive method in the earlier detection of a recurrent cancer.     

Effects of ketanserin on the pacemaker activity and contractility in the isolated, blood-perfused dog atrium

Effects of ketanserin on the pacemaker activity and atrial contractility and on 5-hydroxytryptamine (5-HT)-induced cardiac responses were investigated in the isolated, blood-perfused dog atrium. Ketanserin (1-300 micrograms) injected into the sinus node artery evoked a transient positive followed by a negative chronotropic effect, and a dose above 30 micrograms of ketanserin produced a dose-dependent negative inotropic effect with a little positive one. Ketanserin-induced negative chronotropic and inotropic effects were not affected by atropine in a dose which blocked ACh-induced responses. Propranolol inhibited positive inotropic responses to ketanserin and norepinephrine and significantly augmented the negative chronotropic and inotropic responses to ketanserin. Imipramine did not affect the transient positive followed by negative chronotropic and the negative inotropic responses to ketanserin but it induced the positive cardiac responses following the negative ones. Tetrodotoxin, phentolamine, and diphenhydramine did not modify the effects of ketanserin. From these results, it is concluded that ketanserin might induce the direct negative chronotropic and inotropic effects and the indirect effects by catecholamine release. Ketanserin-induced catecholamine release might not be due to tyramine-like or nicotine-like action. Ketanserin significantly inhibited a low dose (3 micrograms) of 5-HT-induced negative chronotropic and inotropic effects, suggesting the possibility of 5-HT2 receptors in the isolated dog atrium.     

A case of salicylazosulfapyridine (Salazopyrin)-induced acute pancreatitis with positive lymphocyte stimulation test (LST)

A case of acute pancreatitis induced by salicylazosulfapyridine (Salazopyrin, SASP) was reported. A 33-year-old man with ulcerative colitis was given SASP. Five weeks later, P-type serum amylase was found to be elevated. The amylase/creatinine clearance ratio (ACCR) and serum lipase were also elevated. There were neither subjective symptoms nor abnormal ultrasound findings in the pancrease. Lymphocyte stimulation test (LST) to SASP was positive. Asymptomatic pancreatitis by SASP was suspected and SASP administration was halted. Afterwards the abnormal data became normal. Readministration of SASP because of relapse caused an episode of pancreatitis similar to the first occasion. LST was negative before SASP intake and became positive after intake. Desensitization to SASP was unsuccessful. LST was negative before attempting desensitization and became positive when the dosage of SASP increased to 100 mg daily. This is the second case of acute pancreatitis reported to be induced by SASP and this is the first case in which LST to SASP was described. To our knowledge, this is also the first case in which a positive LST was described in drug-induced pancreatitis. This case provides evidence for the role of delayed type hypersensitivity in the etiopathogenesis of SASP allergy and of dose-independent drug-induced pancreatitis.     

Right pneumonectomy syndrome: Report of two cases

We report herein the cases of two infants who developed right pneumonectomy syndrome, both of whom were born with gross C-type esophageal atresia (EA/TEF), and a hypoplastic right lung arising from the lower esophagus, being a bronchopulmonary foregut malformation (BPFM). Appropriate and well-timed treatments for a variety of sequelae primarily caused by the mediastinal shift must be considered after right pneumonectomy in early childhood.     

A Possible Role of the Pineal Gland in Acute Immobilization-Related Suppression of Naloxone-Induced LH Release in Ovariectomized Estrogen-Primed Rats

It has been recently reported that acute immobilization stress almost completely suppresses the luteinizing hormone (LH) release induced by naloxone, a μ-opioid antagonist, in ovariectomized estrogen-primed rats. The present study examined the possible involvement of the pineal gland in the acute immobilization-related suppression of the naloxone-induced LH release. An intraventricular (ICV) injection of 15 μg naloxone produced an abrupt increase in circulating LH concentrations in non-stressed rats. The naloxone-induced LH release was completely eliminated when tested 60 min after the end of a 30 min session of acute immobilization. The same stress conditions did not affect LH-releasing hormone (LHRH)-induced LH release, suggesting that the stress-related suppression of the naloxone-induced LH release was a suprapituitary event. In chronically-pinealectomized rats, but not in sham-pinealectomized rats, naloxone injected 60 min after the end of the stress session evoked a significant increase in serum LH concentrations. However, naloxone injected ICV during the acute immobilization did not elicit LH release in either pinealectomized or sham-operated rats. Under non-stressed conditions, the LH secretory response to naloxone was similar in pinealectomized and sham-operated animals. The same stress (30 min immobilization) significantly increased pineal melatonin content as well as plasma melatonin concentrations in rats bearing intact pineal glands, indicating that stress actually affected the pineal function. These results provide evidence for a role of the pineal in the suppression of the LH response to naloxone after stress, but not during stress.