Cytological and histological changes in the middle ear after inoculation of influenza A virus

Experimental otitis media induced in the chinchilla by inoculation of influenza A virus into the middle ear resulted in capillary engorgement, subepithelial hemorrhage, tissue edema and acute inflammatory cell infiltration. Quantitative morphometric measurements were made for 28 days. Ciliated cells appeared to be the primary target of this strain of influenza virus and demonstrated the greatest degree of damage. Three weeks were required to restore the ciliated epithelium in the tubotympanum to normal levels.

Tetrahydrobiopterin synthesis is induced by LPS in vascular smooth muscle and is rate-limiting for nitric oxide production

GTPCH1 mRNA and BH4 synthesis is increased by LPS in vascular smooth muscle. Our data suggest that induction of GTPCH1 and NOS represent two arms of a common pathway required for immunostimulant-evoked NO synthesis. This conclusion is consistent with the view that the major function of immunostimulant-evoked BH4 is to support NOS. Moreover, GTPCH1 and other enzymes of the de novo BH4 synthetic pathway may prove to be important targets for therapy of clinical conditions arising from NO overproduction. As we begin to reveal the molecular events governing the induction and expression of GTPCH1 and NOS, additional therapeutic approaches for treating NO overproduction are certain to be revealed.

Susceptibility of various animals to Pneumocystis carinii infection

Pneumocystis carinii (Pc) is an important opportunistic pathogen of immune compromised hosts, and is known to infect various animals. The present study observed the infection status of 6 mammals and 3 strains of albino rats with Pc after suppression of their immunity. Methyl-prednisolone was injected once a week and tetracycline was supplied with water for 5 to 21 weeks. Hamsters, guinea pigs, rabbits, dogs, cats and pigs were negative by impression smear, and only the rats were found infected by Pc. All of the three strains of rats, Sprague-Dawley(SD), Wistar(W) and Fisher(F), were infected by Pc but W rats showed heavier degree of infection in earlier period than F or SD rats. The present findings suggest that W rat is the best among the animals used in the present study for production of Pc.

In vivo model for pseudo-templated transcription in Sendai virus

A synthetic Sendai virus-like recombinant RNA was used to develop a model system for pseudo-templated transcription of the P/C gene. The synthetic RNA molecule contains a 42-base stretch of nucleotide sequence derived from the RNA editing site of the P/C gene embedded into the chloramphenicol acetyltransferase gene. When this construct was rescued into Sendai virus, it was found that this 42-base sequence was sufficient to allow the Sendai virus polymerase to transcribe mRNAs with G-nucleotide insertions. Edited mRNA species containing a single nontemplated G insertion were found at a frequency of 6.5%, while rare messages had two G residues inserted. Edited viral RNA was not apparent, suggesting that this event is appropriately excluded during replication of the model genome. By progressively deleting from the 3' end, we found that a 24-nucleotide sequence spanning the G-insertion site was sufficient for pseudo-templated transcription in our system.

Catalytic properties of the cloned amylase from Bacillus licheniformis

A gene encoding a new amylolytic enzyme of Bacillus licheniformis (BLMA) has been cloned, and we characterized the enzyme expressed in Escherichia coli. The genomic DNA of B. licheniformis was double-digested with EcoRI and BamHI and ligated the pBR322. The transformed E. coli was selected by its amylolytic activity, which carries the recombinant plasmid pIJ322 containing a 3.5-kilobase fragment of B. licheniformis DNA. The purified enzyme encoded by pIJ322 was capable of hydrolyzing pullulan and cyclodextrin as well as starch. It was active over a pH range of 6-8 and its optimum temperature was 50 degrees C. The molecular weight of the enzyme was 64,000, and the isoelectric point was 5.4. It degraded soluble starch by cleaving maltose units preferentially but did not attack alpha-1,6-linkage. The enzyme also hydrolyzed pullulan to panose units exclusively. In the presence of glucose, however, it transferred the panosyl moiety to glucose with the formation of alpha-1,6-linkage. The specificity of transferring activity is evident from the result of the maltosyl-transferring reaction which produces isopanose from maltotriose and glucose. The molecular structure of the enzyme deduced from the nucleotide sequence of the clone maintains limited similarity in the conserved regions to the other amylolytic enzymes.

Nitric oxide is a mediator of hypoxic coronary vasodilatation. Relation to adenosine and cyclooxygenase-derived metabolites

Hypoxia is a potent coronary-vasodilating signal; its mechanisms are still controversial. We have assessed the possible role of nitric oxide (NO) in hypoxic coronary vasodilatation (HCVD) in isolated guinea pig hearts perfused at constant pressure. HCVD was elicited by a 1-minute 100% N2 exposure; coronary flow doubled within 1 minute of hypoxia (early phase) and returned to baseline within 40 seconds after reoxygenation (late phase). The early phase of HCVD was associated with a rapid approximately eightfold increase in cGMP overflow, an indication of NO release. The specific NO synthase inhibitor N omega-methyl-L-arginine (NMA, 0.1-1 mM) antagonized HCVD and the associated increase in cGMP spillover (maximum inhibition, approximately 65%); excess arginine (1.2 mM) prevented both effects. The late phase of HCVD was associated with an increase in adenosine overflow and was attenuated by the adenosine receptor antagonist BW A1433 (1 microM; maximum inhibition, approximately 45%). Indomethacin (10 microM) inhibited HCVD in spontaneously beating hearts by approximately 35% but had no effect in hearts paced at faster rates. NMA and BW A1433 were more effective in combination than alone (maximum inhibition, approximately 72%). However, irrespective of the concentrations used, there was no synergism among the anti-HCVD effects of NMA, BW A1433, and indomethacin, nor was HCVD completely inhibited by the antagonists, whether alone or in combination. Our findings indicate that NO is an important mediator of the early phase of HCVD, whereas additional mechanisms and/or factors, including adenosine and vasodilatatory prostaglandins, contribute to the late phase.

Relationship between activities of cytochrome P-450 monooxygenases in human placental microsomes and binding of benzo(a)pyrene metabolites to calf thymus DNA

Benzo(a)pyrene metabolism in human placental microsomes from smokers was studied. Benzo(a)pyrene metabolites were separated using high pressure liquid chromatographic technique. Reaction of benzo(a)pyrene with a microsomal fraction of placenta from individuals who smoke cigarettes during pregnancy yields 7,8 dihydroxy benzo(a)pyrene as a major metabolite, while 3'-hydroxy benzo(a)pyrene, 4,5 dihydroxy benzo(a)pyrene and quinones constitute minor metabolites. The activities of arylhydrocarbon hydroxylase and 7-ethoxycoumarin deethylase exhibited much higher activities in smokers than in nonsmokers. Examination of specific binding of monoclonal antibodies to cytochrome P-450 isozymes in placental microsomes revealed that cigarette smoking specifically enhanced the level of cytochrome P-450 c and d isozymes in human placental microsomes. Coincubation of 3H-benzo(a)pyrene and calf thymus DNA with placental microsomes yielded acid insoluble 3H-B(a)P from smokers, suggesting that cigarette smoking may induce placental enzymes which convert benzo(a)pyrene into ultimate metabolites to form carcinogen-DNA adducts.

Simultaneous determination of haloperidol and its metabolite, reduced haloperidol, in plasma, blood, urine and tissue homogenates by high-performance liquid chromatography

A high-performance liquid chromatographic method was developed for the simultaneous determination of haloperidol and reduced haloperidol in human plasma, urine and rat tissue homogenates using bromperidol as an internal standard. The method involved extraction followed by injection of 50-80 microliters of the aqueous layer onto a C18 reversed-phase column. The mobile phase was 0.5 M phosphate buffer-acetonitrile-methanol (58:31:11, v/v/v) and the flow-rate was 0.6 ml/min. The column effluent was monitored by ultraviolet detection at 214 nm. The retention times for reduced haloperidol, haloperidol and bromperidol were 5.4, 7.2 and 8.4 min, respectively. The detection limits for haloperidol and reduced haloperidol in human plasma were both 0.5 ng/ml, and the corresponding values in human urine were both 5 ng/ml. The coefficients of variation of the assay were generally low (below 10.7%) for plasma, urine, blood and tissue homogenates. No interferences from endogenous substances or any drug tested were found.

Effects of serotonin1-like receptor agonists on autonomic neurotransmission

Serotonin1A receptor agonists, 8-hydroxy-2-(di-n-propylamino)tetralin and 10-methyl-11-hydroxyaporphine, inhibited electrical stimulation-induced contraction of the guinea-pig ileum. These agonists also inhibited the pressor and tachycardiac responses to low frequency (0.25 Hz) but not to high frequency (2.0 Hz) electrical stimulation of the sympathetic nervous system in pithed rats. Serotonin1B receptor agonist RU 24969 inhibited pressor and tachycardiac responses to both low and high frequencies of stimulation in pithed rats. In the cat nictitating membrane, serotonin1A receptor agonists did not alter contractions elicited by electrical stimulation (0.1-3.0 Hz). Serotonin not only contracted the cat nictitating membrane but also facilitated contractile responses to low frequency (0.1-1.0 Hz) stimulation. The contractile effect of serotonin in the cat nictitating membrane was blunted by bretylium, methysergide, and ketanserin, but not by metoclopramide. The facilitatory effect of serotonin was antagonized by methysergide, but not by ketanserin, pindolol, propranolol, or metoclopramide. These results suggest that serotonin1A receptors modulate autonomic neurotransmission in the guinea-pig ileum and pithed rats, but not in the cat nictitating membrane. Serotonin contracts the cat nictitating mebrane via serotonin2 subtypes, while facilitating stimulated contractile responses through the serotonin1-like receptors.

Evaluation of the central and peripheral components for induction of postural hypotension by guanethidine, clonidine, dopamine2 receptor agonists and 5-hydroxytryptamine1A receptor agonists

Previously, it was observed that the severity of postural hypotension in rats after i.v. administration is: guanethidine (severe) greater than clonidine greater than dopamine2 (DA2) receptor agonists greater than 5-hydroxytryptamine1A (5-HT1A) receptor agonists (none). In this paper we investigated central and peripheral mechanisms involved in postural hypotension induced by these drugs. Intracerebroventricular or intracisternal doses of the above agents produced a fall in mean arterial pressure of 32 to 42 mm Hg and were used for evaluation of the central component. Intracerebroventricular, but not intracisternal, clonidine induced postural hypotension. DA2 or 5-HT1A receptor agonists did not induce postural hypotension after either i.c.v. or intracisternal administration. Intracerebroventricular guanethidine did not lower arterial pressure dose-dependently, or did it produce postural hypotension. A peripheral action postulated to be involved in the postural hypotension was inhibition of sympathetic neurotransmission; to evaluate this inhibition, drug effects on pressor and tachycardiac responses elicited by electrical stimulation in pithed rats were determined. Inhibition of heart rate changes by each of the drugs was: guanethidine, 60 to 100% at 0.1 to 8.0 Hz; clonidine, 20 to 40% at 0.1 to 2.0 Hz; DA2 receptor agonists, 10 to 45% at 0.1 to 2.0 Hz; and 5-HT1A receptor agonists, 20 to 40% at less than or equal to 0.5 Hz. These data indicate that the frequency selective inhibition in the peripheral sympathetic nervous system may explain the likelihood of postural hypotension for guanethidine, clonidine DA2 and 5-HT1A receptor agonists. Clonidine has some central component for induction of postural hypotension in addition to the frequency-related peripheral component.

Rescue of a foreign gene by Sendai virus

A simple protocol for the rescue of a synthetic genome into a paramyxovirus has been developed. First, a synthetic Sendai virus-like RNA, containing the antisense coding region of the chloramphenicol acetyltransferase gene replacing the coding region of the Sendai virus genome, was transcribed from a cDNA. When introduced into cells that are infected with Sendai virus, this RNA construct was transcribed, replicated, and packaged into infectious virions. The addition of infected cell extract to the RNA prior to transfection markedly enhanced levels of chloramphenicol acetyltransferase expression and rescue. However, this enhancement is not due to encapsidation of the RNA into nucleocapsids as the RNA remains nuclease-sensitive. Uninfected cell extract also enhances expression and rescue efficiency, implying involvement of a cellular factor(s) with the synthetic viral-like RNA construct that allows for enhanced polymerase recognition. This system should allow for the dissection of the various cis-acting RNA signals within the paramyxovirus genome.

Electrophysiological improvement following decompression surgery in tarsal tunnel syndrome

Plantar nerve conduction studies 14 months to 3.5 years after decompression surgery in 3 cases of tarsal tunnel syndrome showed an improvement in motor conduction as well as in sensory nerve conduction. This electrophysiological improvement was associated with clinical improvement. However, minor abnormalities still existed in sensory nerve conduction in all 3 cases.

Reversal of antihypertensive agent-induced postural hypotension with physostigmine

Physostigmine, administered intravenously, reversed postural hypotension induced by hypotensive agents, guanethidine, clonidine and dopamine2-receptor agonists. Postural hypotension, induced by pentobarbital sodium, was also reversed by physostigmine. Neostigmine reversed postural hypotension induced by clonidine following intracerebroventricular, but not intravenous administration. It is proposed that centrally acting cholinomimetic agents may be used to manage postural hypotension resulting from suppression of sympathetic nervous system activity.

Modulation by physostigmine of head-up tilt- and bilateral carotid occlusion-induced baroreflexes in rats

In anesthetized normotensive rats, 45 degrees head-up tilt induced a transient marked drop followed by a long-lasting slight drop in mean arterial pressure (MAP), and with cessation of tilt there is a transient pressor response. Heart rate (HR) did not change appreciably by tilting. Bilateral occlusion of common carotid arteries (BCO) induced pressor responses with tachycardia. Physostigmine (5 and 15 micrograms i.c.v.) attenuated the tilt-induced decreases in MAP. Neither the HR during tilt nor the restoration-related transient pressor response was altered by physostigmine. Acetylcholine (ACh, 5 micrograms i.c.v.) exhibited a similar attenuation of tilt-induced changes in MAP. Physostigmine enhanced BCO-induced pressor responses whereas not affecting BCO-induced HR responses. The time for onset of these changes in arterial pressure was slower than that of physostigmine-induced pressor response. Depletion of brain ACh with hemicholinium-3 (20 micrograms i.c.v.) or its derivative A-5 (20 micrograms i.c.v.) or blockade of muscarinic-receptors with atropine (1 microgram i.c.v.) blocked physostigmine-elicited modulation of both tilt- and BCO-induced reflexes. These results suggest involvement of central cholinergic systems for modulation not only of BCO-induced but also tilt-induced cardiovascular reflexes. In particular, ACh appears to enhance these reflexes by acting within the central nervous system.

Purification of monomeric agmatine iminohydrolase from soybean

Agmatine iminohydrolase (EC 3.5.3.12) was purified to homogeneity from the cytosol of soybean (Glycine max) axes by chromatographic separations on Sephadex G-25, Bio-rex 70, and agmatine-affinity columns. The enzyme was homogeneous by the criteria of analytical gel electrophoresis. Molecular weights estimated by Sephadex G-100 gel and sodium dodecyl sulfate polyacrylamide gel electrophoresis were 70,000, indicating that the soybean axes enzyme is a monomer, in contrast to the dimeric enzymes from corn and rice. The isoelectric point determined by gel electrofocusing was 7.5, higher than that of the corn enzyme (4.7). The optimal pH and temperature for activity were 6.5 and 50 degrees C, respectively. The enzyme has high specificity for agmatine, and the Km for agmatine was 2.5 x 10(-3) molar. The enzyme was sensitive to Cu2+ and also was inhibited by p-hydroxymercuribenzoate.

Frequency selective compounds and inhibition of cardiovascular reflexes

In anesthetized normotensive rats, several classes of antihypertensive agents (i.v. injection) were compared for their effects on mean arterial pressure (MAP) and reflex-induced changes in MAP produced by 45 degrees head-up tilt, bilateral carotid occlusion (BCO) and stimulation of the central end of sciatic nerves (SNS). Two doses which produced average MAP fall of 32 to 47 mm Hg were used for comparison. Guanethidine (1 and 3 mg/kg) depressed markedly not only the tilt responses but also responses to BCO and SNS. In contrast, clonidine (2 and 6 micrograms/kg) or dopamine2 receptor agonists, apomorphine (100 and 300 micrograms/kg) and VICO-81 (trans-6,9-dimethoxy-1-n-propyl-1,2,3,4,4a,5,10,10a-octahydrobenzo[g] quinoline, 60 and 200 micrograms/kg), only prolonged the time required for compensation. Apomorphine inhibited BCO reflexes slightly, not affecting SNS-induced responses. However, neither the BCO nor the SNS responses were influenced by VICO-81. On the other hand, serotonin1A receptor agonists, (8-hydroxy-2-di-n-propylaminotetralin, 100 and 300 micrograms/kg) and PM-1000 (10-methyl-11-hydroxyaporphine, 1 and 3 mg/kg), did not inhibit responses to tilt. MAP during tilt was somewhat higher than controls after the two serotonin1A receptor agonists. Although BCO or SNS was not influenced by 8-hydroxy-2-di-n-propylaminotetralin, both responses were depressed slightly by higher doses of PM-1000 (3 mg/kg). To correlate the degree of inhibition on tilt reflex with that on sympathetic neurotransmission after these hypotensive agents, plasma catecholamines, norepinephrine, epinephrine and dopamine, were measured.(ABSTRACT TRUNCATED AT 250 WORDS)

Myxoma of the skin of a finger

A case of a true myxoma of the fingertip is presented. The lesion was removed by simple shave excision. Reports of myxoma of the skin are reviewed, and the differential diagnosis of this rare tumor is discussed.

Aspergillosis of the paranasal sinuses--diagnostic significance of the computed tomography

Aspergillosis of the paranasal sinuses appears to be relatively rare in occurrence, but there is a growing incidence of it in accordance with the increasing use of antibiotics, steroid hormones, anticancer drugs, and radiation therapy. We have seen 15 cases of aspergillosis of the paranasal sinuses in which computed tomography (CT) was helpful for diagnosis. The characteristic feature of CT findings was the intermixture of high and low density areas in the affected paranasal sinuses, apparently caused by increased X-ray absorption due to calcification. These findings indicate that CT is useful in the preoperative diagnosis of aspergillosis of the paranasal sinuses.

Testosterone metabolism by microsomal cytochrome P-450 in liver of rats treated with some inducers

1. The stereoselective hydroxylation of testosterone by microsomal cytochrome P-450 and the changes in level of components participated in the microsomal electron transport system were observed in the microsomes induced unique P-450 isozymes. 2. Flavone- and hesperetin-inducible P-450 catalyzed the hydroxylation of testosterone more effectively than other chemicals-inducible ones. 3. The P-450 in all the microsomal preparations tested most rapidly oxidized testosterone to 6 beta-monohydroxy form. 4. Particularly, MC- and BNF-inducible P-450 showed high stereoselectivity on C6-position of testosterone, and PB-, flavone- and hesperetin-inducible one showed that on C2-position of this compound, respectively. 5. This specificity of two flavonoid-inducible P-450 for the formation of 2 alpha- and 2 beta-epimer of monohydroxytestosterone was opposite to each other. 6. The content of P-450 and the activity of NADPH-cytochrome P-450 reductase were high in PB-, MC- and BNF-microsomes, whereas NADH-cytochrome b5 reductase activity was high in two flavonoid-microsomes and the content of cytochrome b5 was not changed except the PB-treated rats. 7. It is suggested that the increasing activities of testosterone hydroxylases in flavonoid-microsomes seems to be closely related to NADH-cytochrome b5 reductase.

Adult Wilms' tumor--a case report

A case of Wilms' tumor in a 67 year-old female is presented. The tumor totally replaced the left kidney with extension to Gerota's fascia, the adrenal gland and ureter, with tumor thrombi in the left renal vein. Multiple bony metastases to the skull, shoulder, rib, ilium, acetabulum and femur were noted also. Microscopically, the tumor was composed predominantly of blastemal tissue with diffuse anaplasia with areas of tubular differentiation and chondroid elements. Clear cell nests were found in the proximal ureter with gradual maturation downward.

Modulation of glycoprotein hormone alpha-subunit levels, alkaline phosphatase activity, and DNA replication by antimetabolites in HeLa cultures

Synthesis of the glycoprotein hormone common alpha-subunit and alkaline phosphatase (placental isozyme) has been examined in HeLa S3 cells. A variety of compounds that inhibit DNA synthesis lead to the increased production of both proteins. Experiments presented in this communication were undertaken to determine whether protein induction and DNA synthesis inhibition are coordinated. In general, nucleoside analogs and compounds that alter deoxynucleotide metabolism were good inducers of these ectopic products, whereas agents that altered DNA by intercalation, crosslinking, and covalent modification were poor inducers. The former class of effectors includes 5-bromo-2'-deoxyuridine, 5-fluoro-2'-deoxyuridine, 2'-deoxythymidine, 1-beta-D-arabinofuranosylcytosine, methotrexate, hydroxyurea, N-phosphonoacetyl-L-aspartic acid, and sodium butyrate; and the latter class of compounds includes ethidium bromide, acridine, bleomycin, mitomycin C, cesalin, macromomycin, and cis-diamminedichloroplatinum(II). A direct correlation between protein induction and DNA synthesis inhibition is unlikely based on the following observations: (i) for some effectors, the concentrations required to induce alpha-subunit and PAP were significantly different from those necessary to inhibit DNA synthesis; (ii) several agents inhibit DNA replication but do not enhance hormone or enzyme production; (iii) the kinetics of ectopic protein induction were similar for a number of inducers whereas the kinetics of DNA synthesis inhibition elicited by the same compounds were quite different. It is difficult from the data obtained, however, to rule out the possibility that inhibition of DNA synthesis may be required but is not sufficient for protein induction.

Gonadotropin and prolactin secretion increases during sleep during the puerperium in nonlactating women

To investigate the neuroendocrine changes that regulate initiation of normal menstrual function after parturition, serum LH, FSH, and PRL concentrations were determined at 20-min intervals for 12-24 h in eight nonlactating postpartum women on a weekly basis between postpartum days 10-26. Sleep was monitored by EEG. On postpartum day 10, serum LH concentrations were similar to early follicular phase levels in normal cycling women, while FSH concentrations were lower than early follicular phase levels. Mean LH pulse frequency during each postpartum interval was 3.6 +/- 0.6 (+/- SE), 4.4 +/- 0.6, and 4.1 +/- 0.8 pulses/12 h on postpartum days 10-11, 17-21, and 24-26, respectively. Because mean serum LH levels and LH pulse frequency did not change significantly between postpartum days 10 and 26, the results from the two or three studies in each woman were combined for the purpose of comparing LH pulse characteristics during the waking and sleeping periods. During the waking hours, mean LH pulse frequency (6.1 +/- 0.5 pulses/12 h) was significantly greater than during sleep (4.1 +/- 0.4 pulses/12 h; P less than 0.02). The amplitude of the serum immunoreactive LH pulses (P less than 0.05) and bioactive LH levels (P less than 0.05) were significantly higher during sleep than during the waking period, with five of the eight women having higher sleep-associated immunoreactive LH and bioactive LH levels between postpartum days 17-26. These changes were associated with an increase in the bioactive to immunoactive LH ratio from 3.3 +/- 0.4 (awake) to 4.5 +/- 0.5 (sleep; P less than 0.05). Although serum PRL levels remained elevated during the puerperium, the diurnal pattern of PRL secretion was conserved. With each successive week postpartum, serum PRL concentrations declined. These results suggest that the increment in LH secretion (and, by inference, increased GnRH secretion) during sleep is a feature of postpartum pituitary-ovarian reactivation. Although the mechanism(s) responsible for the increase in GnRH secretion is not known, this hormonal pattern is analogous to that during early puberty and during recovery from anorexia nervosa and hypothalamic amenorrhea. Taken together, these findings provide evidence to support the concept of a centralized preprogrammed scheme for pituitary-gonadal reactivation.