[Ischemic hepatitis due to anthracycline-induced cardiac insufficiency in a patient with acute myelocytic leukemia (M0)]

A 25 year-old woman diagnosed as acute myelocytic leukemia (M0) suffered a fourth relapse in February 1992 at which time she already had anthracycline-induced cardiac dysfunction. Although remission was induced by low dose cytosine arabinoside and etoposide combined with pirarubicin, she developed acute heart failure followed by extreme elevation of transaminases level and DIC. Abdominal echography and CT revealed small round lesions in the liver. We diagnosed this episode as ischemic hepatitis because of the following clinical findings; serological markers of virus hepatitis were negative, hypotension and reduced blood flow to the liver were seen, and both transaminases and LDH were markedly elevated. Dobutamin and oxygen inhalation were started, her liver function returned to almost normal levels 8 days later.

Multiple TL-like loci in the grc-G/C region of the rat

The grc-G/C region of the rat is homologous to the Q/TL region of the mouse, and deletions in this region are associated with fetal mortality, developmental defects, and decreased resistance to cancer. Several cosmids spanning approximately 45 kilobases of this region were analyzed for their class I loci, using a mouse general class I probe (pAG64c), grc-specific probes (pGRC1.4, pGRC1.7), and four probes derived from the TL-like locus RT1.N1. The results showed that TL-like genes other than RT1.N1 exist in the rat: a duplicated gene, RT1.N2, was identified, sequenced, and shown to be 99.3% similar to RT1.N1; and a third TL-like gene, RT1.N3, was isolated from a cDNA library, sequenced, and shown to be 92.8% similar to RT1.N1. These observations suggest that the rat TL-like loci are duplicated and that there is more than one cluster of these duplicated genes. The TL-like genes are transcribed predominantly in the thymus, except in grc- strains, and their level of transcription increases during fetal life and reaches its maximum at birth. Finally, a cosmid that appears to identify the end of the deletion in grc- strains was identified.

Myelination of regenerated optic fibers in peripheral nerve graft of adult cats

Retinal ganglion cells of adult cats have the potential to regenerate their axons into autografted peripheral nerve. Two months after transplantation of the sciatic nerve to the axotomized optic stump, regenerated axons were labeled anterogradely with biocytin, and myelin formation by Schwann cells was examined electron microscopically. Both myelinated and unmyelinated fibers were labeled with biocytin. Among 511 axons labeled in three grafts, 96 fibers (18.8%) were myelinated and 415 (81.2%) were unmyelinated. Mean diameter with SD of myelinated fibers was 1.28 +/- 0.39 micron (range 0.71-2.47) and that of unmyelinated fibers was 0.76 +/- 0.38 micron (range 0.18-2.46). The ratio of inner to outer diameters of the myelin sheath (g value) was 0.82, which is close to the value (0.8) for the optic fibers of intact adult cats.

Inhibition of erythroid differentiation by stem cell factor in K562 cells expressing the c-kit gene

We found a K562 subclone (K562YO) that highly expressed the c-kit gene. K562YO had a higher capability of erythroid differentiation by hemin and cytosine arabinoside (Ara-C) than its parent K562 (KIT-). We obtained the transfectant expressing c-kit by introducing c-kit cDNA into K562 (KIT-). The differentiation of the transfectant was similar to that of the parent cell. Thus the difference described above was not due to the expression of c-kit. Next, we investigated the effects of stem cell factor (SCF) on the differentiation of the K562 cell expressing c-kit. SCF did not enhance the cell growth of K562YO. On the other hand, SCF suppressed induction of benzidine-positive cells when c-kit-positive cells were treated with hemin and Ara-C, especially at a low concentration. Furthermore, c-kit mRNA and protein were down-regulated during erythroid differentiation. SCF also downregulated the c-kit proteins. Our results suggest that the SCF/c-kit signals could act negatively for erythroid differentiation of the K562 cells expressing c-kit. K562YO is also useful for studying the mechanism that controls the expression of the c-kit gene because there is a K562 counterpart cell line that does not express this gene.

Number, distribution, and morphology of retinal ganglion cells with axons regenerated into peripheral nerve graft in adult cats

The optic nerve of adult cats was transected and an autologous peripheral nerve was transplanted to the stump. Two months later retinal ganglion cells (RGCs) that had regenerated their axons were retrogradely labeled with fluorescent dye injected into the graft. The more than 4000 labeled cells, which were 3.0-4.3% of total ganglion cell number in the intact retina, were distributed in a high-density area elongating horizontally, in a pattern similar to that observed in the intact retina. The dendritic morphology of RGCs with regenerated axons was examined after intracellular injections of HRP or Lucifer yellow in vitro. The morphology of alpha- and gamma-cells appeared comparable to normal, whereas the dendrites of some beta-cells seemed to degenerate. Some "unclassified" cells could not be identified as alpha-, beta-, or gamma-cells. The main dendrites of most unclassified cells were thin and less ramified than alpha- and beta-cells. Some unclassified cells had a vacant area in their dendritic fields, suggesting degenerative change in dendrites. The distal dendrites of some unclassified and gamma-cells had many fine processes that probably regrew during axonal regeneration. The proportion of alpha-, beta-, and other cells including gamma- and unclassified cells in the regenerating cell population was evaluated by examining all of the Lucifer yellow-injected cells in local patches. The average proportion of alpha-cells was 23.9%, about six times higher than in intact retinas. The average proportion of beta-cells was 50.3%, slightly higher than in intact retinas. The remaining cells (25.7%) could not be categorized as alpha or beta; this proportion is about half that found in intact retinas. These findings suggest that alpha-cells have the highest capacity to regenerate their axons into nerve grafts, rather than all types equally regenerating their axons.

Stable production of recombinant human sperm immobilizing antibody using cDNA expression vectors

PROBLEM

Sperm immobilizing antibodies present in sterile women may be one of the principal causes of immunological infertility. We already established cell lines that secrete recombinant human IgG sperm immobilizing antibody using class-switched (from IgM to IgG) genomic immunoglobulin genes. However, these transfectants produced a small quantity of antibody and required continuous use of a medium with selective reagents. We have now constructed cell lines that stably secrete the antibody in large quantities using immunoglobulin cDNAs and cDNA expression vectors.

METHOD

The immunoglobulin heavy chain cDNA was cloned from transfectants that secrete the class-switched human IgG sperm immobilizing antibody. The light chain cDNA, which had already been cloned, and the heavy chain cDNA were inserted into the modified bovine papilloma virus-based cDNA expression vectors BCMGSNeo and BCMGSHyg, respectively. These constructs were sequentially transfected into a mouse myeloma cell line by electroporation.

RESULTS

The established transfectants produced recombinant antibody that retained human sperm immobilizing activity in nonselective medium for at least 30 days. Moreover, the production of the antibody was increased three times over that of the previous cell lines.

CONCLUSION

We have established an unique method that improves the production of sperm immobilizing antibody stably and in large quantities.

Axonal regeneration of retinal ganglion cells in the cat geniculocortical pathway

The optic nerve of anesthetized cats was completely cut and the autologous sciatic nerve was transplanted. Sixty days later some populations of retinal ganglion cells were shown to regenerate the axon with retrograde HRP labeling. We verified that ganglion cells that had projected to the lateral geniculate nucleus (LGN) were able to regenerate through the transplant with a double-labeling method: diI was injected into the LGN prior to the transplantation, and dextran-fluorescein was injected into the graft after axonal regeneration. Intracellular injection of HRP into regenerating ganglion cells in an in vitro preparation revealed that the two major cell types projecting to the LGN, alpha and beta, regenerated axons and showed normal dendritic morphology.

Cysteamine-induced duodenal ulcer and the hepatoduodenal branch of the vagus nerve

We investigated the role of the autonomic nervous system in gastric acid secretion, somatostatin concentration and PAS-positive mucus production in Brunner's glands in cysteamine-induced duodenal ulcer. Vagotomized rats were used. No ulcers occurred in the groups with vagotomies of the hepatoduodenal, truncal or gastric branches after cysteamine administration. However, in the hepatoduodenal branch vagotomized group, there was an increase in gastric acid secretion after cysteamine administration. A similar increase was observed in the control group, but the decreases in somatostatin concentration and PAS-positive mucus seen in the control group were not found in the hepatoduodenal vagotomized group. These results suggest that the hepatoduodenal branch of the vagus nerve might play an important role in the ulcerogenic process of cysteamine-induced duodenal ulcer.

[An early combined endodermal sinus tumor of the ovary that was diagnosed due to torsion of serous cystadenoma--a case report]

Reported is a rare case of a 2.5cm endodermal sinus tumor (EST) that was included within a 11 x 10.5 cm serous cystadenoma. A 24-year-old female suddenly complained of abdominal pain caused by having undergone an intestinal torsion of a left ovarian tumor. After a unilateral salpingo-oophorectomy the serum AFP was 219.8 ng/ml. The patient then received two cycles of cis-platinum, vinblastine and bleomycin combination chemotherapy. After one cycle, the serum AFP decreased to a normal level and the woman has remained free of disease 6 months after the discovery of her tumor. In this case, fortunately, this torsion of a serous cystadenoma enabled us to find the EST at a very early stage.

Studies on bilokinase, a biliary plasminogen activator: immunologic property and organ distribution

The aim of the present study was to elucidate the immunologic difference between bilokinase, a plasminogen activator in bile, and urokinase, an urinary plasminogen activator, and to demonstrate the organ distribution of these antigens. Polyclonal antibodies against the highly purified activators (bovine-bilokinase, -urokinase and human urokinase) were raised in rabbits or guinea pigs. Immunologic precipitin reactions and quenching were found to occur only between the activators and their respective antisera. Histo-immunologic demonstration of the activators revealed that bilokinase-antigen was localized mainly in the hepatocytes as well as in the mucosa of the gall bladder, whereas urokinase-antigen was present in the epithelium of the urinary tubules. The liver may have a potential role in the hepatobiliary fibrinolytic system.

Nasotemporal overlap of crossed and uncrossed retinal ganglion cell projections in the Japanese monkey (Macaca fuscata)

The nasotemporal overlap of crossed and uncrossed retinal ganglion cell projections were studied in 11 Japanese monkeys (Macaca fuscata) using HRP and fluorescent dyes (DAPI and RITC) as retrograde tracers and by physiological recordings of antidromic field potentials. A strip of nasotemporal overlap ran orthogonal to the horizontal meridian in all the whole-mount retinas studied. In HRP-labeled retinas of 6 monkeys, the width of the overlap gradually increased from 0.6 degrees in the central retina up to 5 degrees at eccentricity of 5 mm, and to 15 degrees at the extreme periphery. We also noted a clear asymmetric distribution of crossed and uncrossed retinal ganglion cell projections particularly in the perifoveal region; ipsilaterally projecting cells encircled the nasal edge of the fovea, whereas few contralaterally projecting cells were observed in the temporal edge. Soma-size analysis revealed that crossed projections in the temporal portion of the overlap arose mainly from large and small cells (presumably P alpha and P gamma cells, respectively); uncrossed projections in its nasal portion arose from medium-sized cells (presumably P beta cell). Direct evidence of the overlap as well as of the asymmetry was obtained in subsequent fluorescent dye experiments in 3 monkeys. Physiological studies on 2 additional monkeys confirmed the widening of the nasotemporal overlap towards the upper and lower parts of the retina. Moreover, in the nasal portion of the overlap, only slow potentials, which presumably reflect activities of P beta cells, were recorded after stimulation of the ipsilateral LGN as expected from the morphological study. The findings are discussed in relation to clinical observations of macular sparing and splitting, and with regard to the functional differences between P alpha and P beta cell systems on which binocular stereoscopic vision along the midsagittal plane may be based.

Synthesis and characterization of 1-substituted 5-alkylphenazine derivatives carrying functional groups

The following 1-substituted derivatives of 5-methylphenazine and 5-ethylphenazine were synthesized: 1-(3-carboxypropyloxy)-5-methylphenazine (1B), 1-(3-carboxypropyloxy)-5-ethylphenazine (2B), 1-(3-ethoxycarbonylpropyloxy)-5-ethylphenazine (2C) and 1-[N-(2-aminoethyl)carbamoylpropyloxy]-5-ethylphenazine (2D); their spectra, stability and reactivity as electron mediators were investigated, together with those of 5-methylphenazine (1A) and 5-ethylphenazine (2A). The 1-substituted derivatives are all insensitive to light and the derivatives of 5-ethylphenazine are more stable than those of 5-methylphenazine under neutral and alkaline conditions; 2B is the most stable of all the derivatives. The spectral properties of the decomposed compounds showed that photodecomposition of 1A and 2A is associated with hydroxylation at position 1, alkali decomposition of 1A and 1B with elimination of the 5-methyl group and alkali decomposition of 2A, 2B, and 2D with a ring-opening reaction. The second-order rate constant k1 for the reaction of the phenazine derivatives with NADH was measured under steady-state conditions. The k1 values vary depending on the substituents at positions 1 and 5: the values for 1A, 1B, 2A, 2B, 2C and 2D are 1.83 mM-1 s-1, 3.33 mM-1 s-1, 0.75 mM-1 s-1, 1.42 mM-1 s-1, 1.68 mM-1 s-1 and 2.03 mM-1 s-1, respectively. The rate constants, k2 and k3, for the reactions of the reduced form of 2B with oxygen and with 3-(4',5'-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium ion, respectively, were k2 = 1.21 mM-1 s-1 and k3 = 91 mM-1 s-1. These phenazine derivatives have potential applications in the biochemical field.

Preparation and kinetic properties of 5-ethylphenazine-poly(ethylene glycol)-NAD+ conjugate, a unique catalyst having an intramolecular reaction step

5-Ethylphenazine-poly(ethylene glycol)-NAD+ conjugate (EP+-PEG-NAD+) was prepared by linking 1-(3-carboxypropyloxy)-5-ethylphenazine (I) to poly(ethylene glycol)-bound NAD+ (PEG-NAD+) and its kinetic properties were studied. As a reference compound, poly(ethylene glycol)-bound 5-ethylphenazine derivative (III) was also prepared and the effects of poly(ethylene glycol) on the reaction rate of the 5-ethylphenazine moiety with NADH was investigated. The second-order rate constant, k1, of the reaction of III with NADH is 2.78 mM-1 s-1 and is about 1.7 times that of 1-(3-ethoxycarbonylpropyloxy)-5-ethylphenazine (II) with NADH. A similar effect of the attached poly(ethylene glycol) was observed for the reaction of PEG-NADH with I or II. The second-order rate constants, k2 and k3, of the reactions of the reduced form of III with oxygen and with 3-(4',5'-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium ion, respectively, were k2 = 1.22 mM-1 s-1 and k3 = 32 mM-1 s-1; the k2 value is not changed but the k3 value is decreased by the attachment of the polymer. EP+-PEG-NAD+ works as a unique catalyst having an intramolecular reaction step within its turnover cycle in a coupled multi-step reaction system containing malate dehydrogenase, malate, EP+-PEG-NAD+, a tetrazolium salt and oxygen. The first-order rate constant, k4, of the intramolecular reaction was 1.1 s-1. The effects of the covalent linking of the 5-ethylphenazine and the NAD+ moieties were estimated by comparing the value of k4 with that of k1 for the reaction of III with NADH; the effective concentration of the NADH moiety for the 5-ethylphenazine moiety on the same EP+-PEG-NADH molecule (or vice versa) was calculated to be 0.40 mM from the ratio of k4/k1. The values of the rate constants in the coupled multi-step reaction system enable us to understand the dynamic features of the system and the characteristics of EP+-PEG-NAD+ as a catalyst are discussed.

Intraretinal axons of ganglion cells in the Japanese monkey (Macaca fuscata): conduction velocity and diameter distribution

In anesthetized and immobilized Japanese monkeys (Macaca fuscata), intraretinal conduction velocities of the ganglion cell axons were measured. The field potentials elicited by optic chiasm shocks consisted of fast and slow components with estimated conduction velocities of 1.19 and 0.72 m/s in recordings from the optic nerve fiber layer, and 1.65 and 1.00 m/s in recordings from the ganglion cell layer. Single cell recordings verified that the time course of the fast component corresponded to the antidromic spike latencies of Y-like cells, whereas that of the slow component covered the latency range of both X-like and W-like cells. In an electron microscopic study of the cross-sections of the intraretinal optic nerve fiber bundles, the axon diameter histograms of large samples (n = 3000-6000) all showed a unimodal distribution with a sharp peak at 0.3-0.6 micron and a long tail extending to 2-3 micron. The mean diameter was largest in the ventral and nasal bundles, smallest in the papillomacular bundle and intermediate in the dorsal, upper arcuate and lower arcuate bundles. However, diameter histograms of a small number of regional axons (n = 255-300) showed a broad tail distinct from the peak at 0.3-0.6 micron, enabling us to segregate a group of larger axons from the medium-sized to small axons. From such regional axon diameter histograms we estimated the mean relative occurrences of the larger axons (7.1-11.3%) and their mean diameters (0.9-1.3 micron). We further applied this relative frequency to the unimodal distribution of the histograms with larger samples in the upper and lower arcuate bundles and estimated the mean axon diameter of the large axons (1.1 micron) and that of the medium-sized to small axons (slightly below 0.5 micron). Finally, in studying the relation between axon diameter and conduction velocity in the two arcuate fiber bundles, we found it to be somewhat different from that previously reported for the cat retina.

Effects of EEG synchronization on visual responses of the cat's geniculate relay cells: a comparison among Y, X and W cells

Single unit activities of Y, X and W cells were recorded in the cat lateral geniculate nucleus to study how their responses to stationary light spots change with the cortical EEG. The shift from desynchronized to synchronized EEG drastically suppressed W cell activities, depressed both transient and sustained components of X cell responses, but did not affect the transient component of Y cell responses. This was ascribed to different inhibitory circuitries in the three parallel pathways and their differential modulation by the ascending brainstem activities.

Oligonucleotide formation catalyzed by divalent metal ions. The uniqueness of the ribosyl system

Polymerization of various nucleoside-5'-phosphorimidazolides has been conducted in neutral aqueous solution using divalent metal ions as catalysts. Oligonucleotide formation took place from each of the ribonucleoside-5'-phosphorimidazolides, ImpC, ImpU, ImpA, ImpG, and ImpI. The yields and distributions of the resulting oligonucleotides varied depending on the difference of the nucleic acid base and the metal ions used. The catalytic effect of divalent metal ions on the formation of oligocytidylates occurred in the following order: Pb2+ greater than Zn2+ greater than Co2+, Mn2+ greater than Cd2+ greater than Cu2+ greater than Ni2+ greater than Ca2+, Mg2+, none greater than Hg2+. The order changes slightly for other types of oligoribonucleotide formation. Oligoribonucleotides up to hexamers were obtained in 35-55% overall yield, when Pb2+ ion was used as a catalyst. Zn2+ ions yielded oligoribonucleotides up to tetramers in 10-20% overall yield. The resulting oligonucleotides contained mainly 2'-5' internucleotide linkages. Little or no oligonucleotide was obtained from nucleoside-5'-phosphorimidazolides modified in the sugars, Imp(3'-dA), Imp(2'-dA), Imp(Ara), Imp-(Aris), and Imp(Nep). The results indicate that a ribosyl system is required for the metal ion-catalyzed synthesis of oligonucleotides.

Retinal inputs and laminar distributions of the dorsal lateral geniculate nucleus relay cells in the eastern chipmunk (Tamias sibiricus asiaticus)

Retinal inputs and their laminar distributions in the dorsal lateral geniculate nucleus (LGNd) of the eastern chipmunk (Tamias sibiricus asiaticus) were studied using histological and microelectrode recording techniques. A previous anatomical study (Fukuda et al. 1986a) indicated that the chipmunk LGNd had five laminae: contralaterally (contra) innervated lamina 1 and ipsilaterally (ipsi) innervated lamina 2 in its ventromedial part; laminae 3a (contra), 3b (ipsi) and 3c (contra) in its dorsolateral part. We have confirmed this finding in our present anatomical study and have also noted another ipsilaterally innervated thin lamina 0, medial to lamina 1. In our electrophysiological study, however, we were unable to record units from lamina 0 and to investigate it functionally. We recorded 232 units from laminae 1, 2 and the 3 complex, of which 95 were identified as Y-like, 46 as W-like, 15 as X-like, and 8 as mixed Y/W-like cells; the rest were either unclassified or visually unresponsive. In laminae 1 and 2, only Y-like and X-like cells were recorded, whereas in the laminae 3 complex W-like cells were recorded as well. The results suggest that the chipmunk laminae 1, 2 and 3 complex correspond relatively well to the cat laminae A, A1 and C complex, respectively. In the chipmunk LGNd, however, there were more Y-like cells in laminae 1 and 2, and a few X-like cells of which some were color sensitive. Also, lamina 3a had a concentration of mixed-type cells with Y-like receptive field properties and W-like OX latencies. As for retinotopy, the dorsoventral transition of the contralateral visual field (laminae 1, 3a, 3c) is represented along the dorsoventral dimension of the chipmunk LGNd, whereas the temporonasal transition is represented in the rostrocaudal direction. Receptive field positions of the ipsilaterally innervated relay cells are limited to the central overlapping field of the contralateral visual fields of both eyes. Relay cells with visual fields having elevations of below -20 degrees had relatively fast latency range and Y-like properties.

Anomalous optic nerve fiber convergences in the ipsilateral retinocollicular projection: a comparison of congenitally monocular and neonatally one-eye-removed rats

Single cell responses to electrical stimuli applied to the optic chiasm and to the lateral geniculate nucleus were studied in expanded projection to the ipsilateral superior colliculus of neonatally enucleated and congenitally monocular rats. In both types of rats latencies to the afferent volleys were longer, and the latency correlation between the optic chiasm and the lateral geniculate responses was lower in the ipsilateral than in the contralateral superior colliculus cells. This was interpreted to suggest abnormal convergence of retinal axons with different conduction velocities in the ipsilateral retinocollicular projection. The deviation of ipsilateral superior colliculus cells from the high-latency correlation of the contralateral cells was more marked in congenitally monocular than in neonatally enucleated rats.

Isolation of mycolic acid-containing glycolipids in Nocardia rubra and their granuloma forming activity in mice

Three classes of glycolipids (TMM (trehalose monomycolate), TDM (trehalose dimycolate) and GM (glucose mycolate] containing mycolic acids as hydrophobic components were isolated from a strain of Nocardia rubra (Rhodococcus rubrum) and their structures have been partially characterized using infrared spectrometry, gas-liquid chromatography and gas chromatography-mass spectrometry. Acid or alkaline hydrolysis of isolated glycolipids revealed that trehalose was the sole water soluble component in TMM and TDM, while glucose was the hydrophilic component in GM. On the other hand, saturated, monoenoic and dienoic mycolic acids with carbon atoms ranging from C36 to C50 contained constituents of fatty acid moiety at C44. From the analytical results, TMM, TDM and GM were tentatively identified as trehalose monomycolate, trehalose dimycolate and glucose monomycolate, respectively. The mycolic acid composition differed significantly by the glycolipid classes: the highest amount of saturated mycolic acids were detected in TMM and GM, while a significant amount of dienoic mycolic acids have been found in TDM and the cell wall bound lipid fraction (BL). All these three classes of glycolipids containing mycolic acids showed strong granuloma forming activity in lungs and spleen of ICR mice 1 week after intravenous injection of 100 to 500 micrograms glycolipid in W/O/W micelles containing Freund's incomplete adjuvant. These results indicated that glycolipids containing shorter carbon chain mycolic acids ranging C40-50, corresponding to less acyl numbers or monosaccharides such as glucose, can also produce foreign body-type granuloma in mice without protein antigens.

Synthesis and biological activities of beta-alanyltyrosine derivative of 2',5'-oligoadenylate, and its use in radiobinding assay for 2',5-oligoadenylate

beta-Alanyltyrosine derivative of 2',5'-tetraadenylate 5'-triphosphate, pppA2'p5'A2'-p5'A2'p5'A-beta-Ala-Tyr was prepared by coupling of periodate-oxidized pppA2'p5'-A2'p5'A2'p5'A with beta-alanyltyrosine methyl ester, followed by reduction with sodium cyanoborohydride. Its stability to 2',5'-phosphodiesterase and phosphatase was investigated in mouse L cell extract. The 5'-triphosphate of the compound was cleaved gradually to form the 5'-dephosphorylated derivative, A2'p5'A2'p5'A2'p5'A-beta-Ala-Tyr, followed by slow degradation of the 2',5'-phosphodiester bond. On the other hand, pppA2'p5'A2'p5'A2'p5'A was hydrolyzed very quickly under the same conditions. The tetramer derivative bound tightly to the 2',5'-oligoadenylate-dependent endoribonuclease in rabbit reticulocyte lysate or mouse L cell extract and inhibited protein synthesis of mouse L cells more effectively than the unmodified 2',5'-tetraadenylate 5'-triphosphate. The corresponding trimer derivative had slightly weaker activities than the unmodified trimer for binding to the endoribonuclease and for inhibition of protein synthesis. The compound, pppA2'p5'A2'p5'-A2'p5'A-beta-Ala-Tyr, was iodinated easily at the tyrosine residue with 125I, giving a high-specific-radioactivity derivative which was used as a radio-labeled probe in a radiobinding assay for 2',5'-oligoadenylate.

Ipsilateral retinal projections and laminations of the dorsal lateral geniculate nucleus in the eastern chipmunk (Tamias sibiricus asiaticus)

The ipsilateral retinal projections and laminations of the dorsal geniculate nucleus (LGNd) were studied in the eastern chipmunk (Tamias sibiricus asiaticus). From cyto-, myelo- and chemoarchitectures the LGNd was divided into the ventromedial and dorsolateral parts. Anterograde axonal transport of wheat germ agglutinated horseradish peroxidase (WGA-HRP) and Fink-Heimer staining after unilateral eye removal both indicated that the ipsilateral projection terminates in lamina 2 of the ventromedial part and in lamina 3b of the dorsalateral part. The remaining laminas, lamina 1 of the ventromedial part and laminas 3a and 3c of the dorsolateral part, receive afferents from the contralateral retina. It was suggested that laminas 1 and 2 of the chipmunk's LGNd correspond to laminas A and A1 of the cat's LGNd, and the lamina 3 complex to its lamina C complex.

Detection of elevated levels of 2-5A synthetase in serum from children with various infectious diseases

By a sensitive radioimmunoassay method, (2'-5')oligoadenylate synthetase was detected in serum from patients with viral, bacterial, or mycoplasmal infections at elevated levels compared with enzyme levels in serum from healthy individuals and patients suffering from noninfectious diseases.

Activation of 2-5A-dependent RNase by analogs of 2-5A (5'-O-triphosphoryladenylyl(2'----5')adenylyl(2'----5')adenosine ) using 2',5'-tetraadenylate (core)-cellulose

A variety of 2-5A (px(A2'p)nA; x = 2 or 3, n greater than or equal to 2) analogs were assayed for their abilities to activate murine 2-5A-dependent RNase (subsequently "the nuclease") using a recently developed method. This technique consists of immobilizing and partially purifying the nuclease using core-cellulose [A2'p)3A-cellulose) and then monitoring the breakdown of poly(U)-3'-[32P]Cp into acid-soluble fragments. Several 5'-adenosinecapped analogs of 2-5A (containing a tetra-, tri-, or diphosphate) were analyzed, and it was found that reducing the number of phosphoryl groups between the 5' to 5'-diadenosine linkages resulted in a progressive loss of activity. Because A5' pppp(A2'p)3A was a potent activator of the nuclease yet stable during the assay these results suggested that a free 5'-phosphoryl group may not be required for the activation of the nuclease. A number of 8-bromoadenosine-substituted analogs of 2-5A were also studied. Curiously, the brominations decreased the activities of the 5'-di- and triphosphorylated molecules while substantially increasing the activities of the 5'-monophosphorylated species. The results indicated that a tri- or diphosphate moiety on the 5'-end of 2-5A or the presence of ATP is not absolutely required for the nuclease to be active. Furthermore, the ATP analog, beta, gamma-methylene ATP, did not inhibit the activity of the nuclease. Finally, a 3',5'-phosphodiester linkage isomer of 2-5A and a 3'-deoxy (cordycepin) analog of 2-5A were tested, and both were found to be completely without activity.

Temporary double representation in expanded ipsilateral retinocollicular projection of neonatally one-eye-removed rats

Retinotopic representations of the expanded projection to the ipsilateral colliculus were studied in albino rats of various ages after neonatal unilateral eye removal. Besides the projection from the lower temporal retina the projection from the central retina was observed in 3-6 month-old one-eyed rats. Such double retinotopic representation was not observed in 1-month- or 1-year-old one-eyed rats. A postnatally growing temporary process was suggested for the expanded ipsilateral retinocollicular projection in rats.

Sensitive radioimmuno assay for 2',5'-oligoadenylates using a novel 125I-labeled derivative of 2',5'-triadenylate 5'-triphosphate

A novel 125I-labeled derivative of 2',5'-triadenylate 5'-triphosphate, pppA2'p5'A2'p5'A, with high specific radioactivity was synthesized by coupling of periodate-oxidized pA2'p5'A2'p5'A with beta-alanyltyrosine methyl ester followed by 5'-triphosphorylation and iodination with 125I. Antisera toward 2',5'-oligoadenylate 5'-triphosphate were produced in rabbits by immunization with the conjugate of pppA2'p5'A2'p5'A2'p5'A with bovine serum albumin, and an antiserum with high specificity and high sensitivity for 2',5'-oligoadenylates was selected and tested extensively. Radioimmuno assaying of 2',5'-oligoadenylates was carried out by a competitive double antibody method in which the amount of the antibody bound to the 125I-labeled probe was measured after precipitation with goat anti-rabbit IgG. The concentration of pppA2'p5'A2'p5'A required for 50% inhibition of the binding between the antiserum and the probe was 0.6 nM. The cross reactivity of the antiserum with the 3',5'-triadenylate was more than 10,000 times weaker compared to in the case of 2',5'-oligoadenylates. Very low or no cross reaction was observed with ATP, AMP, and adenosine. The radioimmuno assay using the 125I-labeled compound and the antiserum allows the direct analysis of 2',5'-oligoadenylates in the range of 4 fmol to 1 pmol (0.04-10 nM in a 100 microliter sample). This assay was applied to the measurement of the activity of 2',5'-oligoadenylate synthetase in cells stimulated by interferon. The properties of the 125I-labeled derivative of pppA2'p5'A2'p5'A are described.

Mode of reinnervation in neonatally denervated lamina of the cat's lateral geniculate nucleus

Physiological properties of relay cells were studied in the lateral geniculate nucleus (LGN) of neonatally one-eye-removed adult cats. Most of the relay cells recorded from the denervated lamina (lamina A1) were still classifiable into either Y- or X-cells, like those recorded from the non-denervated lamina (lamina A). However, receptive field centers of both Y- and X-cells in the denervated lamina were slightly over twice as large as those of the corresponding classes in the non-denervated lamina. These data indicate that reinnervated relay cells may receive excessive convergent inputs from either Y or X type retinal axons which have grown translaminarly.

Replacement of the ribofuranose oxygen of 2-5A derivatives by methylene: synthesis of an aristeromycin analogue of 2-5A core 5'-monophosphate (5'-O-phosphoryladenylyl)(2'----5')adenyl(2'----5')adenosine

The ribofuranose oxygens of the three adenosine residues of the 5'-monophosphate of the 2-5A core [adenylyl(2'----5')adenylyl(2'----5')adenosine] were replaced by methylenes through the synthesis of an aristeromycin [9-[(1R,2S,3R,4R)-2,3-dihydroxy-4-(hydroxymethyl)cyclopentyl]adenosine] analogue. In the synthetic approach, the chlorophosphite triester procedure was employed together with the use of dimethoxytrityl and tert-butyldimethylsilyl protecting groups. The final product 14 was bound to the 2-5A-dependent endonuclease of mouse, rabbit, or human cells 100-300 times less effectively than parent p5'A2'p5'A2'p5'A. In extracts of human Daudi cells where the monophosphate p5'A2'p5'A2'p5'A was able to effect ribosomal RNA cleavage at 2 X 10(-7) M, 14 required a concentration of 2 X 10(-5) M to bring about discernible rRNA cleavage.

Axonal projections of X-cells to the superior colliculus and to the nucleus of the optic tract in cats

Axonal projections of ganglion cells to the superior colliculus (SC) and to the nucleus of the optic tract (NOT) were re-examined physiologically in the cat's retina. Taking care to minimize current spreads around the stimulating electrodes placed in the NOT or the SC, we reached a conclusion that a substantial proportion of X-cells project to the NOT while a small but definite proportion of them project to the SC.

Antibody-nucleic acid interactions. Monoclonal antibodies define different antigenic domains in 2',5'-oligoadenylates

To define the epitopes involved in binding anti-oligonucleotide antibodies, several hybridomas producing monoclonal antibodies directed against 2',5'-oligoadenylate were established. A solid-phase enzyme-linked immunoassay that employed microtiter wells coated with Ficoll-2',5'-oligoadenylate conjugates proved useful in screening and characterizing hybridoma supernatants. Control experiments demonstrated that the conjugates were irreversibly adsorbed to polystyrene wells under the conditions employed in the assay. Reactivity of monoclonal antibodies with numerous analogues of 2',5'-oligoadenylate was measured by using a competition assay. Several monoclonal antibodies originating from different mice immunized with the same or different immunogens possessed distinctive fine specificities. At least one 2',5'-phosphodiester bond was important in forming each epitope, suggesting that the ribose phosphate backbone is a critical element in defining an antigenic domain of an oligonucleotide. The purine bases were also important, and modification of the bases had varied effects on the extent of antibody recognition. The length of the oligonucleotide and the nature of the termini were also of some importance. In several instances the modification created by linkage of 2',5'-oligoadenylate to carrier protein also contributed to the determinant. The monoclonal antibody most specific for 2',5'-oligoadenylates was relatively insensitive to ionic strength. In contrast, a monoclonal antibody with a 2',5'-oligopurine specificity appeared to bind 2',5'-oligoadenylate through one ion pair, whereas the binding of a monoclonal antibody with a low degree of base specificity appeared to bind through two ion pairs. The results demonstrated that 2',5'-linked oligoadenylate-protein complexes possess at least three distinct oligonucleotide-related antigenic surfaces that can be recognized with high apparent affinity by monoclonal antibodies. A model for the three epitopes is presented.

Turnover of fibrinopeptide A (FPA) in rabbits

FPA disappeared from the circulating blood along a double-exponential decay curve consisting of an initial phase (t 1/2 = 1.8 min) and a late phase (t 1/2 = 34.7 min). The rapid decrease in blood FPA was due to the large extravascular space, the size of which was estimated to be about 5 times larger than that of intravascular space. The actual amounts of 125I-FPA distributed to the organs and tissues were generally quite low. However, in the case of the urine, the injected amount of FPA was excreted at the rate of 50% per hour. Thus, the urinary FPA levels may reflect the occurrence of intravascular coagulation.

Cordycepin analogs of ppp5'A2'p5'A2'p5'A (2-5A) inhibit protein synthesis through activation of the 2-5A-dependent endonuclease

Analogs of the triphosphate 2'-5'-linked adenylate trimer (ppp5'A2'p5'A2'p5'A, called 2-5A) which contain 3'-deoxyadenosine (cordycepin) instead of adenosine either in positions one and two, or in all three positions, are 10-100-fold less potent than is parent 2-5A in inhibition of protein synthesis in intact cells, when utilizing calcium co-precipitation techniques to introduce the 5'-triphosphate oligonucleotides into the cells. That the inhibition of protein synthesis was a consequence of activation of the 2-5A-dependent endonuclease by the 3'-deoxyadenosine analogs of 2-5A was demonstrated in obtaining the ribosomal RNA cleavage pattern that is characteristic of endonuclease activation by parent 2-5A. Additional results (i.e. lack of activity by the dimer species ppp5'(3'dA)2'p5'-(3'dA) or the monomer 3'dA) as well as kinetic analysis both in intact cells and in cell-free extracts provided further evidence that the inhibition of protein synthesis observed with these 3'-deoxyadenosine 2-5A analogs was not due to their degradation to the antimetabolite monomer unit 3'-deoxyadenosine.

Comparative studies on (2'-5')oligoadenylate-related enzyme systems and the antiviral effect of interferon in two mouse cell lines which differ in (2'-5')oligoadenylate sensitivity of their protein synthesizing system

Effect of (2'-5')oligoadenylate (2-5A) on cellular and viral protein and RNA syntheses was investigated with two mouse cell lines, L929 and Lz (a subclone of L929). The oligonucleotide was introduced into the cells either by using calcium phosphate coprecipitation technique or by microinjection method. In L929 cells protein and viral RNA syntheses were severely inhibited by 2-5A, whereas in Lz cells, both were only slightly inhibited. The activities of 2-5A synthetase and double-stranded (ds)RNA-dependent protein kinase were enhanced by interferon (IFN) treatment roughly to the same extent and there was no significant difference in the level of 2'-5' phosphodiesterase activity either. On the other hand, 2-5A-dependent RNase (RNase L) activity in Lz cells was low, being about 10-20% of that of L929 cells. It was increased twofold after IFN treatment, but protein synthesis of Lz cells was not as sensitive to 2-5A as that of L929 cells even after IFN treatment. L929 and Lz cells were sensitive to the antiviral effect of mouse IFN against vesicular stomatitis virus (VSV) and Mengovirus. In contrast, however, Lz cells were relatively insensitive to the antiviral effect of IFN on vaccinia virus, whereas L929 cells were sensitive.

2',5'-Oligoadenylate and 2',5'-oligoadenylate phosphodiesterase in human plasma

2',5'-Oligoadenylate and 2',5'-oligoadenylate phosphodiesterase activity were detected in the human plasma and serum by sensitive radioimmuno assays. The phosphodiesterase in the serum degraded 20 nM of added 2',5'-oligoadenylate in less than 1 hr. Addition of EDTA in the blood sample inhibited the phosphodiesterase activity completely and allowed the measurement of low levels of 2',5'-oligoadenylate. The concentration in the plasma from healty people was in the range of 0.03 to 0.3 nM.

Retinotopic organizations of the expanded ipsilateral projection to the rat's superior colliculus; variations along its rostrocaudal axis

The retinotopic organization of the expanded projection to the ipsilateral colliculus was studied electrophysiologically in 12 adult albino rats with one eye removed at birth. For comparison, the contralateral projection was rather variable in the representation of the nasotemporal axis of the retina along the rostrocaudal dimension of the colliculus; on the other hand, the representation of dorsal-to-ventral retinal axis onto the mediolateral dimension of the colliculus was relatively stable.

Oligonucleotide structural parameters that influence binding of 5'-O-triphosphoadenylyl-(2'----5')-adenylyl-(2'----5')-adenosine to the 5'-O-triphosphoadenylyl-(2'----5')-adenylyl-(2'----5')-adenosine dependent endoribonuclease: chain length, phosphorylation state, and heterocyclic base

A number of 2',5'-linked oligoadenylates and their analogues were prepared and evaluated for their ability to interact with the 5'-O- triphosphoadenylyl -(2'----5')-adenylyl-(2'----5')-adenosine (2-5A) dependent endoribonuclease of mouse L cells. The oligonucleotides were assayed for their ability to antagonize the action of 2-5A, to displace a radiolabeled probe from the 2-5A-dependent nuclease, or to inhibit translation in a cell-free system. These experiments demonstrated the following: (1) Three AMP residues in a 5'-phosphorylated oligonucleotide were needed for maximum interaction with the endonuclease, and higher oligomers (greater than or equal to 4 AMP residues) did not show significantly higher binding. (2) The third (2'-terminal) adenosine residue was required for optimal binding activity. (3) 5'-Phosphorylation of the oligonucleotide was necessary for maximum binding to the endonuclease, but the first (from the 5' terminus) internucleotide phosphate of higher unphosphorylated or core oligomers, such as A2'p5'A2'p5'A2'p5'A, may partly replace the requirement for a 5'-monophosphate moiety; in agreement with this, the 5'-methyl ester of 5'pA2'p5'A2'p5'A, i.e., Me-p5'A2'p5'A2'p5'A, was bound to the endonuclease as well as or better than the higher core oligomers but approximately 100 times more effectively than the trimer core, A2'p5'A2'p5'A. (4) Base-modified analogues, such as p5'C2'p5'C2'p5'C, p5'U2'p5'U2'p5'U, or p5'I2'p5'I2'p5'I, were at least 2000 times less effectively bound to the endonuclease than p5'A2'p5'A2'p5'A. (5) The triphosphate ppp5 'I2'p5'I2'p5'I was 10 000 times less active than 2-5A as an inhibitor of translation. These latter two points implied the critical role of the adenine N1-nitrogen and/or exocyclic amino group in the binding of 2-5A to the endonuclease.