[The cardiovascular effects after kainate administration into the caudal ventral sections of the medulla oblongata]. Kainate destruction of the caudal ventral medulla's neurons raised by 70-90% the level of arterial pressure within 1 hour in anesthetised rats, the heart rate decreasing by 25-30% at the same time. Presection of the vagus at the neck level prevented the development of bradycardia and accelerated the formation of systemic arterial hypertension after administration of kainic acid to the caudal ventral medulla. The role of the vagal component in transmission of control signals from the ventral medullary structures to the heart and vessels, is discussed.


[The reactions of the arterial and venous microvessels in hypertension and alloxan diabetes in rats]. In hereditary hypertension and chronic diabetes, the number of arterial capillary ends decreased at the arterial side and increased at the venous one in rats. The density of endotheliocyte nuclei decreased in the arteries and increased in the capillaries and veins in the mesentery of the HAHIS rats. The thickening of the venous vessels' walls was more obvious in the SHR rats. The findings suggest different velocities of the proliferative processes in the two types of vessels.


[The mechanisms of the effect of serotonin on the prostacyclin synthesis and coronary vascular resistance of the isolated rat heart]. An early reduction of coronary vascular resistance after serotonin administration was found to be due to the activity of prostacyclin synthesis and an endothelial-relaxing factor in the rat isolated heart. The activating effect of serotonin on the prostacyclin synthesis was inhibited by catanserin and dyltyasem. The latters prevented damage of endotheliocytes and the beginning of a vasal constriction caused by the protracted serotonin action.


[Nitrogen oxide is not an agent of endothelium-mediated arterial dilatation to an increase in the blood flow rate]. I. v. administration of inhibitors of endothelium-mediated synthesis of the oxide of nitrogen raised the arterial blood pressure, constricted the femoral artery and decreased the acetylcholine- and ATP-induced vaso-dilatation in anesthetized cats. However, the dilatation induced by an increased blood flow velocity, was not affected. The data obtained suggest that the endothelium-dependent arterial dilatation is not mediated by oxide of nitrogen formed from L-arginine.


[The neuroendocrine heart and the hypothalamus--hormones of the integration and regulation of coronary vascular tonus]. Neurosecretory hormone formation by atrial ganglionic cells plays a major role in self-regulation of the heart and its coronary circulation, as well as in integration of the atrium with endocrinal hypothalamus. New data on polypeptide hormones and their precursors is presented. Some atrial glycopeptides play the role of the liberins of hypothalamic cardio-active neurohormones thus carrying out the function of integration of endocrinal hypothalamus with the neuroendocrine heart. The problem of neural and humoral ways of the integration are discussed.


[The dependence of the blood pH, PCO2 and PO2 values measured on the microanalyzer on the hematocrit index during hemodilution and hemoconcentration]. The arterial blood's pH, PCO2 and PO2 were shown to depend on the value of hematocrit in erythrocyte suspension in rats. The dependence can be described by the equation of linear regression except the oxygen tension value within its physiological range. A table of corrections is presented for the values of the blood's pH, PCO2 and PO2 for taking into consideration the factor of altered hematocrit in studies of acute anemias.


[The central thermoregulatory action of cholecystokinin-8 and prostaglandin E1]. In unanesthetized rats, the effects of intracerebroventricular injections of prostaglandin E1 (PGE1) and cholecystokinin octapeptide (CCK-8) on body temperature (Tb) regulation were studied. Both PGE1 and CCK-8 evoke hyperthermic responses of short latency and duration. Each substance raises the temperature, irrespective of initial temperature (Tbi). However, the maximal change in Tb and the rate of Tb rise depends on Tbi. A similarity of PGE1 and CCK-8 central thermoregulatory effects and putative roles of these substances in the mechanisms of fever, are discussed.


[The spatial-frequency characteristics of the neuronal receptor fields in area 21 of the cat visual cortex]. 21 area's neurons of the visual cortex revealed obvious low-pass frequency characteristics ranging from 0.05 to 3.5 c/deg in cats. Responses of the neurons to different frequencies ranged from 0.05 to 0.89 c/deg in the left hemisphere and from 0.11 to 3.5 c/deg in the right one. The data obtained suggest that the RF's neurons of the area 21 make low-pass spatial-frequency description of visual images, the left hemisphere making a lower spatial-frequency description of the image than the right one.


[The value and comparative analysis of the energy expenditures of newborn animals and children]. As opposed to adults, infants were found to have 5-fold differences in values of heat production per unit of mass and unit of body surface. Animals of the same age have these differences not over 20-50%. Newborn mature infants could have these differences to reach 50-60%. The data obtained suggest significant differences in the efficiency coefficient values for muscles contractile activity to play the role of the mechanism of heat production control in chemical thermoregulation and postnatal formation of the constancy of main (standard) metabolism.


[The effect of the delta sleep-inducing peptide on seizure activity]. The delta-sleep-inducing peptide (DSIP) suppressed seizure activity in the cat cortical strychnine-induced seizure foci. The DSIP delayed development of corazol kindling in rats, prevented seizure induced with bicucullin and other agents in mice. The DSIP effect was shown to be realised through the action upon reticular black substance. The DSIP seems to take part in endogenous control of the brain excitability.


[The individual reactivity of the granulocytic system under stress]. 1, 3, 5, 7 days after the 24-hr immobilisation stress, the concentration of nuclear-segmental neutrophils and basic proteins were determined in peripheral blood of white rats. 4 patterns of the neutrophils dynamics were revealed. Individual character of decationisation and granulocytopoiesis potentiation was suggested by the data obtained.


[The effect of activation and blockade of the renin-angiotensin system on the hypotensive activity of the cholinergic system]. In anesthetised rats, infusion of angiotensin II increased mean arterial pressure and inhibited the depressor responses to acetylcholine administration. Low doses of angiotensin did not exert this effect. This and other data obtained suggest that angiotensin II inhibits cardiovascular effects of the cholinergic system tonically.


[The systemic and regional hemodynamics of laboratory rats and wild muskrats during diving]. 1-min forceful immersion in water increased mean arterial pressure by 24% in Ondatra, decreased their heart rate by 71% and cardiac output by 36% Respective figures in Wistar rats were as follows: 19%, 62%, and 46% decrease. By the 50th sec of immersion cerebral blood flow increased 13-fold in Ondatra and 6-fold in Wistar rats.


[The microhemodynamics and lymph flow in the small intestine under the action of histamine against a background of water loading and hyperthermia in dogs]. In anesthetized dogs, an increase of the lymph flow and the transcapillary fluid transfer, under the effect of histamine, was due to elevation of capillary hydrostatic pressure and capillary filtration coefficient in the small intestine. Against the background of water load and hyperthermia, histamine induced less obvious shifts of the microhemodynamic parameters and lymph flow in the small intestine.


[The role of the sympathetic cholinergic pathway in the neurogenic control of the release of tissue-type plasminogen activator into the blood]. In anesthetized cats, electric stimulation of the sympathetic chain induced vasoconstriction and release of t-PA from the vascular wall into the blood. Efferent stimulation of the sympathetic chain against the background of alpha-adrenoceptor blockade increased the blood flow and the t-PA activity. Atropin suppressed both the vascular relaxation and the t-PA release into the blood. A neurogenous mechanism controlling t-PA release from the vascular wall caused by activation of sympathetic cholinergic pathway and associated with excitation of vascular M-cholinoreceptors by acetylcholine, has been suggested.


[The effect of rapid changes in lung volume on the postinspiratory phase of the respiratory cycle in decerebrate cats]. In decerebrated cats, fast blowing of the lungs decreased the duration of inspiration, the amplitude of the diaphragmatic nerve ENG, and increased the duration of the second phase of expiration. The duration of postinspiratory phase was increased in proportion to changes in lung volume. Bilateral vagotomy induced a complete disappearance of the reflex responses.


[The action of pyrogenal and endogenous pyrogen on visceral afferent systems]. Pyrogenal in the dose 5 mcg increased the adrenaline release in dogs. Interleukin-1 increased the noradrenaline release. Neither capsaicin, nor M- and N-cholinoreceptor blockade, nor pre-decentralization of the inferior mesenteric ganglion, abolished the effects. Mechanical and chemical stimuli during continuous perfusion of the colon with subliminal doses of pyrogenal increased the adrenaline release, too. A possible direct effect of endotoxins on peripheral adrenergic neurons, is discussed.


[The dynamics of the normalization of the behavioral and neurochemical disorders evoked in rats by deprivation of the paradoxical sleep phase]. The 24-hr deprivation of paradoxical sleep interferes with the passive avoidance response in rats and decreases the absolute amount of proteins in neurons and gliocytes of the raphe nucleus' dorsal portion while increasing the amount of proteins and nucleic acids in the locus coeruleus' cells. The protein metabolism in serotoninergic cells of the raphe nucleus seems to be involved in the processes of memory and behaviour.


[The work of the central and peripheral loops of the thermoregulatory system in a thermophysical model of the rabbit body]. The experiments studied the role of differently located transducers in the thermoregulation system operation: in the centre and in periphery of the rabbit body model. The central contour was shown to maintain the model temperature within given limits. The peripheral contour did not respond at all to a threshold change of the body heat condition.


[Altered responses of heart rate, renal sodium handling and plasma growth hormone to clonidine in type II diabetic patients]. The aim of the present study is to explore whether the renal and cardiovascular response to clonidine in type II diabetic patients is different from that in control subjects, and to clarify the role of central alpha 2-receptor in the regulation of cardiovascular response and sodium handling in type II diabetes mellitus (DM). Thirty-five diabetic inpatients aged 30-71 years (54.1 +/- 9.7) and ten control subjects (N) were enrolled in this study after their fasting plasma glucose had been improved. To evaluate the peripheral sympathetic nerve activity, 24-hour urinary catecholamine was measured, and pulse rate (PR) responses to a 30-second standing test was determined. On another day, blood pressure (BP), PR, plasma norepinephrine (PNE), cyclic AMP (p-cAMP), renin activity (PRA), aldosterone (PAC) and growth hormone (p-GH) were measured at 0, 30, 60, 90, 120, 150, 180 minutes following the oral administration of clonidine (150 micrograms). Type II DM were classified as DM with hyper-response (DM-HR, n = 12) when their PR decreased after clonidine more than that of N, and if not, they were classified as DM with normal response (DM-NR, n = 23). Urinary catecholamine excretions in type II DM were within the normal range. BP, PNE and p-cAMP were markedly decreased with clonidine in similar fashion in DM-NR, DM-HR and N. The percent changes of PNE were correlated positively with the changes of p-cAMP in both N and DM-NR (r = 0.660 and 0.449, respectively), but not in DM-HR. No significant difference in the changes of p-GH (delta p-GH) and integral of GH (the area under the curve) following clonidine administration was observed in the three groups. The decrease in PR was correlated with neither delta p-GH (N: r = 0.082, DM-NR: r = -0.400, DM-HR: r = 0.242) or integral of GH (N: r = 0.191, DM-NR: r = 0.382, DM-HR: r = 0.162). The fractional excretion of sodium (FENa) decreased in N (p < 0.01), increased in DM-NR (p < 0.05) and did not change in DM-HR. The changes of FENa were not correlated with those of PRA and PAC.(ABSTRACT TRUNCATED AT 400 WORDS)


The effect of IL-6 on the des-gamma-carboxy prothrombin synthesis in human hepatoma cells. Effects of several cytokines on des-gamma-carboxy prothrombin (PIVKA II) synthesis in human hepatoma cells were investigated to know the process of PIVKA II production during a liver allograft rejection. Human recombinant interleukin-6 (IL-6) significantly stimulated the PIVKA II synthesis without any influence on the cell proliferation. The effect was almost completely neutralized by the specific anti-IL-6 antibody. Neither tumor necrosis factor (TNF), interleukin-1 (IL-1) nor interferon-gamma (IFN-gamma) had such a stimulative effect. IL-6 appears to stimulate PIVKA II production, and would be a candidate of factors that enhance the production of PIVKA II during a liver allograft rejection.


Increased expression of Epstein-Barr virus in primary biliary cirrhosis patients. Peripheral blood mononuclear cells (PBMC, n = 26), formalin-fixed paraffin-embedded liver tissues (n = 11) and saliva (n = 15) of primary biliary cirrhosis (PBC) patients were used for the detection of Epstein-Barr virus (EBV) sequences by polymerase chain reaction (PCR) assay. The semiquantitative analysis of EBV-DNA was also carried out in a reconstructive experiment using an EBV-infected cell line. The PBMCs of PBC patients showed increased levels of EBV-DNA (61%) in contrast to chronic active hepatitis patients (19%), liver cirrhosis patients (14%) and healthy individuals (11%). Furthermore, formalin-fixed paraffin-embedded liver tissues, as well as saliva from PBC patients, also demonstrated increased levels of EBV-DNA when compared to healthy individuals and those with other liver diseases. The increased levels of EBV-DNA in the PBMC, liver tissue and saliva of the PBC patients suggest that those patients may have a depressed immune function against EBV infection.


Fungal 17 beta-hydroxysteroid dehydrogenase. Two representatives of each of different fungal taxonomic classes were tested for constitutive 17 beta-hydroxysteroid dehydrogenase (HSDH) activity and the results were positive in all cases. The enzyme was found to be regioselective for C17 of the steroid ring and 20 beta-HSDH activity was only detected in Trichoderma viride. In most cases the oxidative pathway is favoured over the reductive pathway. The possible role of this enzyme in fungi is discussed.


Dominant effects of suppressor of Hairy-wing mutations on gypsy-induced alleles of forked and cut in Drosophila melanogaster. Mutations induced by the gypsy retrotransposon in the forked (f) and cut (ct) loci render their expression under the control of the suppressor of Hairy-wing [su(Hw)] gene. This action is usually recessive, but su(Hw) acts as a dominant on the alleles fk, ctk and ctMRpN30. Molecular analysis of the gypsy element present in fk indicates that this allele is caused by the insertion of a modified gypsy in which the region normally containing twelve copies of the octamer-like repeat that interacts with the su(Hw) product is altered. Analysis of the gypsy element responsible for the ctk and ctMRpN30 mutations also reveals a correlation between the dominant action of su(Hw) and disruption of the octamer region. We propose that these disruptions alter the affinity and interaction of su(Hw) protein with gypsy DNA, thereby sensitizing the mutant phenotype to fluctuations in su(Hw) product.


Analysis of subtelomeric heterochromatin in the Drosophila minichromosome Dp1187 by single P element insertional mutagenesis. We investigated whether single P element insertional mutagenesis could be used to analyze heterochromatin within the Drosophila minichromosome Dp1187. Forty-five insertions of the P[lacZ,rosy+] element onto Dp1187 (recovered among 7,825 transpositions) were highly clustered. None was recovered in centromeric heterochromatin, but 39 occurred about 40 kb from the distal telomere within a 4.7-kb hotspot containing tandem copies of a novel 1.8-kb repetitive DNA sequence. The DNA within and distal to this region lacked essential genes and displayed several other properties characteristic of heterochromatin. The rosy+ genes within the inserted transposons were inhibited by position-effect variegation, and the subtelomeric region was underrepresented in polytene salivary gland cells. These experiments demonstrated that P elements preferentially transpose into a small subset of heterochromatic sites, providing a versatile method for studying the structure and function of these chromosome regions. This approach revealed that a Drosophila chromosome contains a large region of subtelomeric heterochromatin with specific structural and genetic properties.


Active Mutator elements suppress the knotted phenotype and increase recombination at the Kn1-O tandem duplication. The KNOTTED-1 (KN1) locus is defined by a number of dominant mutations that affect leaf development. The Kn1-O mutation is characterized by outpocketings of tissue along lateral veins of the maize leaf and by displacement of ligule tissue from the junction of the blade and sheath into the blade. Kn1-O results from a tandem duplication of 17 kb; each repeat includes the entire 8-kb KN1 transcription unit. Mutator (Mu) transposable elements inserted at the junction of the two repeats diminish the mutant phenotype. The Mu insertions affect the Kn1-O mutation in several distinctive ways. (1) Two of the three Mu elements, a Mu1 and a Mu8 element, diminish the mutant phenotype only when active as indicated by hypomethylation; when methylated or inactive, the phenotype is comparable to the Kn1-O progenitor. (2) Additional rearrangements have arisen in these derivatives that further reduce the mutant phenotype. (3) A 100-2000-fold increase in the loss of one repeat occurs in the presence of Mu elements as compared to Kn1-O without elements. The high frequency of loss only occurs when the Mu elements are hypomethylated. The frequency is also influenced by the specific allele carried at the same locus on the homologous chromosome. Reciprocal exchange of flanking markers does not accompany the loss events. Various recombination models that address the events occurring at Kn1-O are presented.


[Analysis of the conjugation system of plasmid pBS1001 with a broad range of hosts]. Tn5-induced tra mutations were localized on the physical map of a broad host range plasmid pBS1001. Mutations were united into three clusters covering 25% of plasmid DNA. They were distributed in 7 groups by complementation analysis. It was shown that coexistence of tra mutants of pBS1001 and RP4 within the same cell did not restore conjugation properties of both plasmids. High frequency mobilization of some known vectors by pBS1001 was demonstrated.


[Insertion of the Doc mobile element into Drosophila satellite DNA]. Eight plasmids containing the satellite DNA of Drosophila melanogaster, density of 1,688 g/cm3, and DNA neighbouring sequences were selected from gene cosmid library. The Doc mobile element appeared to be present in three cosmids, together with the satellite DNA. Two Doc copies in the opposite orientations are present in one of these cosmids. One monomer of the satellite DNA is located between their 3'-ends, which indicates selectivity of the mobile element insertion into the monomer of this satellite DNA.


[Preparation and analysis of new mutations of the mod(mdg4) gene in Drosophila melanogaster]. In the previous work, we described the modifier of mdg4 gene and obtained one mutation in the locus designated as mod (mdg4). Here we tried to obtain new alleles of this gene participating in transcription control of mdg4. P-M hybrid dysgenesis and EMS treatment failed to give mutations. On the other hand, one strain containing mod (mdg4) 1u1 mutation spontaneously became unstable. In this strain, four novel mod (mdg4) alleles with different phenotypes have been obtained. The mutation obtained seem to be the regulatory ones.


The distribution of transposable elements within and between chromosomes in a population of Drosophila melanogaster. I. Element frequencies and distribution. Data were collected on the distribution of nine families of transposable elements among second and third chromosomes isolated from a natural population of Drosophila melanogaster, by means of in situ hybridization of element probes to polytene chromosomes. It was found that the copy numbers per chromosome in the distal sections of the chromosome arms followed a Poisson distribution. Elements appeared to be distributed randomly along the distal sections of the chromosome arms. There was no evidence for linkage disequilibrium in the distal sections of the chromosomes, but some significant disequilibrium was detected in proximal regions. There were many significant correlations between different element families with respect to the identity of the sites that were occupied in the sample. There were also significant correlations between families with respect to sites at which elements achieved relatively high frequencies. Element frequencies per chromosome band were generally low in the distal sections, but were higher proximally. These results are discussed in the light of models of the population dynamics of transposable elements. It is concluded that they provide strong evidence for the operation of a force or forces opposing transpositional increase in copy number. The data suggest that the rate of transposition per element per generation is of the order of 10(-4), for the elements included in this study.


The distribution of transposable elements within and between chromosomes in a population of Drosophila melanogaster. II. Inferences on the nature of selection against elements. Data were collected on the distribution of nine families of transposable elements among a sample of autosomes isolated from a natural population of Drosophila melanogaster, by means of in situ hybridization of biotinylated probes to polytene chromosomes. There is no general tendency for elements to accumulate at the tips of chromosomes. Elements tend to be present in excess of random expectation in the euchromatin proximal to the centromeres of the major autosomes, and on chromosome four. There is considerable heterogeneity between different families in the extent of this excess. The overall abundance of element families is inversely related to the extent to which they accumulate proximally. The level of proximal accumulation for the major autosomes is similar to that on the fourth chromosome, but less than that for the X chromosome. There is an overall deficiency of elements in the mid-section of the X compared with the mid-sections of the major autosomes, with considerable heterogeneity between families. The magnitude of this deficiency is positively related to the extent to which elements accumulate proximally. No such deficiency is seen if the proximal regions of the X and autosomes are compared. There is a small and non-significant excess of elements in third chromosomes carrying inversions. There is some between-year heterogeneity in element abundance. The implications of these findings are discussed, and it is concluded that they generally support the hypothesis that transposable element abundance is regulated primarily by the deleterious fitness consequences of meiotic ectopic exchange between elements. If this is the case, such exchange must be very infrequent in the proximal euchromatin, and the elements detected in population surveys of this kind must be inserted into sites where they have negligible mutational effects on fitness.


Comparative evolution of P-M system and infection by the sigma virus in French and Spanish populations of Drosophila melanogaster. In 1983, an extensive survey of populations of D. melanogaster was started in a southern French region (Languedoc) in two non-Mendelian systems: the P-M system of transposable elements and the hereditary Rhabdovirus sigma. Unexpectedly fast-evolving phenomena were observed and interesting correlations were noted, giving similar geographical pattern to the region in both systems. For these reasons, the analysis was continued and extended towards the north (Rhône Valley) and the south (Spain). In the P-M system, all the Languedoc populations evolved from 1983 to 1991 towards the Q type which is characteristic of the Rhône Valley populations. In contrast, M' strains are currently observed in the southernmost French populations and in all Spanish ones, so that there is a clear pattern in their geographical distribution. The frequency of flies infected by the sigma virus dramatically increased from 1983 to 1988 in Languedoc; this increase was clearly correlated with some viral characteristics. But, in northern France, similar characteristics did not trigger any increase in the frequency of infected flies. The data presented here show that the distinctive features of Languedoc extend northwards through the Rhône Valley up to Lyon and disappears southwards before the Spanish border.


Genomic distribution of transposable elements among individuals of an inbred Drosophila line. The stability of the elements of eleven transposon families (412, B 104, blood, 297, 1731, G, copia, mdg 4, hobo, jockey and I) has been compared by the Southern technique among individuals of a Drosophila line that has been subjected to 30 generations of sister sib matings. The 412, B104, blood, 297, 1731 and G elements appear stable. Heterochromatic copia and hobo elements and euchromatic I elements appear highly polymorphic. In addition, copia, mdg 4, jockey and I elements undergo an instability resulting in significant variations in relative intensity among autoradiographic bands. The extent of the polymorphisms detected strongly suggests de novo rearrangements of transposable elements.


The role of the transposable element hobo in the origin of endemic inversions in wild populations of Drosophila melanogaster. Evidence from in situ hybridizations of DNA from the transposable element hobo to polytene salivary gland chromosome squashes reveals that hobo occupies both cytological breakpoints of three of four endemic inversions sampled from natural populations of Drosophila melanogaster in the Hawaiian islands. The fourth endemic inversion has a single hobo insert at one breakpoint. Cosmopolitan inversions on the same chromosomes do not show this association. Frequencies of both endemic and cosmopolitan inversions in Hawaiian populations fall in ranges typical for natural populations of D. melanogaster sampled worldwide, suggesting that these results may be typical of other regions besides Hawaii. This appears to be the first direct demonstration that transposable elements are responsible for causing specific rearrangements found in nature; consequently, it is also the first direct demonstration that chromosome rearrangements can arise in nature in a manner predicted by results of hybrid dysgenic crosses in the laboratory. Possible population genetic and evolutionary consequences are discussed.


Modular transposition and the dynamical structure of eukaryote regulatory evolution. This paper examines a model in which transposable elements provide a modular architecture for the cellular genome, complemented by cellular recombinational transformations, arising in turn as a dynamical consequence of this modular structure. It is proposed that the ecology of transposable elements in a given organism is a function of recombinational protocols of the evolving cellular genome. In mammals this is proposed to involve coordinated meiosis-phased activation of LINEs, SINEs and retrogenes complemented by endogenous retroviral transfer between cells.


Transposable DNA elements and life history traits. I. Transposition of P DNA elements in somatic cells reduces the lifespan of Drosophila melanogaster. As an initial study of the influence of transposable DNA elements on life history traits, and as a model system for estimating the impact of somatic genetic damage on longevity, the effect of P DNA element movement in somatic cells on adult lifespan was measured in Drosophila melanogaster males. Lifespan was significantly reduced in males that contained the somatically active P[ry+ delta 2-3](99B) element and 17, 4, 3, but not just a single P element. Furthermore, there appears to be a direct correlation between the number of transposing P elements and the amount of lifespan reduction. This reduction in lifespan observed in males with somatically active P elements is probably due to genetic damage in embryos, larvae and pupae from P-element excisions and insertions, leading to changes in gene structure and regulation, chromosome breakage, and subsequent cell death in adults. This hypothesis is supported in this study by a significant increase in recessive sex-linked lethal mutations in the same males that had reduced lifespans and by the previous observation of chromosome breakage in somatic cells of similar males. The evolutionary implications of these results are discussed, including the possible influence of somatic DNA transpositions on fitness and other life history traits.


Ty1-copia group retrotransposons and the evolution of retroelements in the eukaryotes. Ty1-copia group retrotransposons are among the best studied transposable elements in the eukaryotes. This review discusses the extent of these transposons in the eukaryote kingdoms and compares models for the evolution of these genetic elements in the light of recent phylogenetic data. These data show that the Ty1-copia group is widespread among invertebrate eukaryotes, especially in the higher plant kingdom, where these genetic elements are unusually common and heterogeneous in their sequence. The phylogenetic data also suggest that the present day spectrum of Ty1-copia group retrotransposons has been influenced both by divergence during vertical transmission down evolving lineages and by horizontal transmission between distantly related species. Lastly, the factors affecting Ty1-copia group retrotransposon copy number and sequence heterogeneity in eukaryotic genomes and the effects of transpositional quiescence and defective retrotransposons upon evolution of Ty1-copia group retrotransposons are discussed.


The population biology and evolutionary significance of Ty elements in Saccharomyces cerevisiae. The basic structure and properties of Ty elements are considered with special reference to their role as agents of evolutionary change. Ty elements may generate genetic variation for fitness by their action as mutagens, as well as by providing regions of portable homology for recombination. The mutational spectra generated by Ty1 transposition events may, due to their target specificity and gene regulatory capabilities, possess a higher frequency of adaptively favorable mutations than spectra resulting from other types of mutational processes. Laboratory strains contain between 25-35 elements, and in both these and industrial strains the insertions appear quite stable. In contrast, a wide variation in Ty number is seen in wild isolates, with a lower average number/genome. Factors which may determine Ty copy number in populations include transposition rates (dependent on Ty copy number and mating type), and stabilization of Ty elements in the genome as well as selection for and against Ty insertions in the genome. Although the average effect of Ty transpositions are deleterious, populations initiated with a single clone containing a single Ty element steadily accumulated Ty elements over 1,000 generations. Direct evidence that Ty transposition events can be selectively favored is provided by experiments in which populations containing large amounts of variability for Ty1 copy number were maintained for approximately 100 generations in a homogeneous environment. At their termination, the frequency of clones containing 0 Ty elements had decreased to approximately 0.0, and the populations had became dominated by a small number of clones containing > 0 Ty elements. No such reduction in variability was observed in populations maintained in a structured environment, though changes in Ty number were observed. The implications of genetic (mating type and ploidy) changes and environmental fluctuations for the long-term persistence of Ty elements within the S. cerevisiae species group are discussed.


Evolution of the transposable element Uhu in five species of Hawaiian Drosophila. The complete DNA sequence of three independent isolates of Uhu, a member of the Tc1-like class of transposable elements from D. heteroneura (Uhu-1, Uhu-3, and Uhu-4), has been determined. These isolates have between 95 and 96.4% nucleotide sequence identity indicating that Uhu is well conserved within this species. A comparison of the DNA sequences of Uhu and the D. melanogaster Hb1 transposable element shows that the nucleotide substitution rate for Uhu is comparable to the synonymous rate for the Adh gene in these species. Uhu has been identified in four other species of endemic Hawaiian Drosophila, D. silvestris, D. differens, D. planitibia and D. picticornis, and nine Uhu elements were isolated from genomic libraries of these four species. A 444 base pair region from within the coding region of the Uhu element, with well conserved ends, was amplified by the polymerase chain reaction and used for sequence comparison of elements from different species. The analysis of the sequence similarities between the elements within and between the species shows a grouping of the two pairs of most closely related species (D. heteroneura and D. silvestris, and D. differens and D. planitibia), but shows a much larger variation within the most recently diverged species (D. heteroneura and D. silvestris) than expected. There are extensive nucleotide substitutions and deletions in the Uhu elements from D. picticornis showing that they are degenerating and being lost in this species. These observations indicate that the Uhu element has been transmitted vertically and that transposition may have been activated at the time of formation of each species as it colonized the newly formed islands of the Hawaiian archipelago.


Evolutionary dynamics of transposable elements in prokaryotes and eukaryotes. This paper summarizes some recent theories about the evolution of transposable genetic elements in outbreeding, sexual eukaryotic organisms. The evolutionary possibilities available to self-replicating transposable elements are shown to vary depending on the reproductive biology of the host genome. This effect can be used to explain, in part, the differences in abundance of transposable elements between prokaryotes and eukaryotes. It is argued that the pattern of sexual outbreeding seen in mammals and plants is especially favorable to the spread of transposons. Moreover, because transposon spread is facilitated by zygote formation, the evolutionary origin of sexual conjugation may have been due to selection on transposon-encoded genes. Finally, evidence is also presented that introns could have originated as transposable genetic elements.


Horizontal transfer of P elements and other short inverted repeat transposons. Evidence for horizontal transfer of the P family of transposable elements in the genus Drosophila is reviewed and evaluated, along with observations consistent with the recent invasion of Drosophila melanogaster by these elements. Some other examples of horizontal transfer involving other groups of transposable elements having short inverted terminal repeats are also briefly described. The sequential mechanistic steps likely to be involved in a horizontal transfer event are explored, including the requirement for suitable interspecific vectors or carriers. Finally, the frequency and significance of horizontal transfer of transposable elements are briefly discussed within an evolutionary framework.


Transposable elements and the evolution of genome organization in mammals. All mammalian transposable elements characterized to date appear to be nonrandomly distributed in the mammalian genome. While no element has been found to be exclusively restricted in its chromosomal location, LINE elements and some retrovirus-like elements are preferentially accumulated in G-banding regions of the chromosomes, and in some cases in the sex chromosomes, while SINE elements occur preferentially in R-banding regions. Four mechanisms are presented which may explain the nonrandom genomic distribution of mammalian transposons: i) sequence-specific insertion, ii) S-phase insertion, iii) ectopic excision, and iv) recombinational editing. Some of the available data are consistent with each of these four models, but no single model is sufficient to explain all of the existing data.


Genome canalization: the coevolution of transposable and interspersed repetitive elements with single copy DNA. Transposable and interspersed repetitive elements (TIREs) are ubiquitous features of both prokaryotic and eukaryotic genomes. However, controversy has arisen as to whether these sequences represent useless 'selfish' DNA elements, with no cellular function, as opposed to useful genetic units. In this review, we selected two insect species, the Dipteran Drosophila and the Lepidopteran Bombyx mori (the silkmoth), in an attempt to resolve this debate. These two species were selected on the basis of the special interest that our laboratory has had over the years in Bombyx with its well known molecular and developmental biology, and the wealth of genetic data that exist for Drosophila. In addition, these two species represent contrasting repetitive element types and patterns of distribution. On one hand, Bombyx exhibits the short interspersion pattern in which Alu-like TIREs predominate while Drosophila possesses the long interspersion pattern in which retroviral-like TIREs are prevalent. In Bombyx, the main TIRE family is Bm-1 while the Drosophila group contains predominantly copia-like elements, non-LTR retroposons, bacterial-type retroposons and fold-back transposable elements sequences. Our analysis of the information revealed highly non-random patterns of both TIRE biology and evolution, more indicative of these sequences acting as genomic symbionts under cellular regulation rather than useless or selfish junk DNA. In addition, we extended our analysis of potential TIRE functionality to what is known from other eukaryotic systems. From this study, it became apparent that these DNA elements may have originated as innocuous or selfish sequences and then adopted functions. The mechanism for this conversion from non-functionality to specific roles is a process of coevolution between the repetitive element and other cellular DNA often times in close physical proximity. The resulting interdependence between repetitive elements and other cellular sequences restrict the number of evolutionarily successful mutational changes for a given function or cistron. This mutual limitation is what we call genome canalization. Well documented examples are discussed to support this hypothesis and a mechanistic model is presented for how such genomic canalization can occur. Also proposed are empirical studies which would support or invalidate aspects of this hypothesis.


The splicing of transposable elements and its role in intron evolution. Recent studies have demonstrated that transposable elements in maize and Drosophila are spliced from pre-mRNA. These transposable element introns represent the first examples of recent addition of introns into nuclear genes. The eight reported examples of transposable element splicing include members of the maize Ac/Ds and Spm/dSpm and the Drosophila P and 412 element families. The details of the splicing of these transposable elements and their relevance to models of intron origin are discussed.


Intragenic suppression: Stalker, a retrovirus-like transposable element, can compensate for a deficiency at the cut locus of Drosophila melanogaster. A number of mutations at the cut locus were induced by non-precise excision of a silent P-element insertion which resulted in deletions at the regulatory region of the locus. Unexpectedly, a reversion of one of these mutations was found, which appears as a result of insertion of Stalker (a retrovirus-like mobile element) near the 1.3 kb deletion. Thus an insertion of a retrovirus-like mobile element can suppress the deficiency at the regulatory region of a gene.


Evolution of the transposable element mariner in the Drosophila melanogaster species group. The population biology and molecular evolution of the transposable element mariner has been studied in the eight species of the melanogaster subgroup of the Drosophila subgenus Sophophora. The element occurs in D. simulans, D. mauritiana, D. sechellia, D. teissieri, and D. yakuba, but is not found in D. melanogaster, D. erecta, or D. orena. Sequence comparisons suggest that the mariner element was present in the ancestor of the species subgroup and was lost in some of the lineages. Most species contain both active and inactive mariner elements. A deletion of most of the 3' end characterizes many elements in D. teissieri, but in other species the inactive elements differ from active ones only by simple nucleotide substitutions or small additions/deletions. Active mariner elements from all species are quite similar in nucleotide sequence, although there are some species-specific differences. Many, but not all, of the inactive elements are also quite closely related. The genome of D. mauritiana contains 20-30 copies of mariner, that of D. simulans 0-10, and that of D. sechellia only two copies (at fixed positions in the genome). The mariner situation in D. sechellia may reflect a reduced effective population size owing to the restricted geographical range of this species and its ecological specialization to the fruit of Morinda citrifolia.


Nonautonomous transposable elements in prokaryotes and eukaryotes. Defective (nonautonomous) copies of transposable elements are relatively common in the genomes of eukaryotes but less common in the genomes of prokaryotes. With regard to transposable elements that exist exclusively in the form of DNA (nonretroviral transposable elements), nonautonomous elements may play a role in the regulation of transposition. In prokaryotes, plasmid-mediated horizontal transmission probably imposes a selection against nonautonomous elements, since nonautonomous elements are incapable of mobilizing themselves. The lower relative frequency of nonautonomous elements in prokaryotes may also reflect the coupling of transcription and translation, which may bias toward the cis activation of transposition. The cis bias we suggest need not be absolute in order to militate against the long-term maintenance of prokaryotic elements unable to transpose on their own. Furthermore, any cis bias in transposition would also decrease the opportunity for trans repression of transposition by nonautonomous elements.


Evolution of Ac and Dsl elements in select grasses (Poaceae). We present data on evolution of the Ac/Ds family of transposable elements in select grasses (Poaceae). An Ac-like element was cloned from a DNA library of the grass Pennisetum glaucum (pearl millet) and 2387 bp of it have been sequenced. When the pearl millet Ac-like sequence is aligned with the corresponding region of the maize Ac sequence, it is found that all sequences corresponding to intron II in maize Ac are absent in pearl millet Ac. Kimura's evolutionary distance between maize and pearl millet Ac sequences is estimated to be 0.429 +/- 0.020 nucleotide substitutions per site. This value is not significantly different from the average number of synonymous substitutions for coding regions of the Adh1 gene between maize and pearl millet, which is 0.395 +/- 0.051 nucleotide substitutions per site. If we can assume Ac and Adh1 divergence times are equivalent between maize and pearl millet, then the above calculations suggest Ac-like sequences have probably not been strongly constrained by natural selection. The level of DNA sequence divergence between maize and pearl millet Ac sequences, the estimated date when maize and pearl millet diverged (25-40 million years ago), coupled with their reproductive isolation/lack of current genetic exchange, all support the theory that Ac-like sequences have not been recently introduced into pearl millet from maize. Instead, Ac-like sequences were probably present in the progenitor of maize and pearl millet, and have thus existed in the grasses for at least 25 million years. Ac-like sequences may be widely distributed among the grasses. We also present the first 2 Ds1 controlling element sequences from teosinte species: Zea luxurians and Zea perennis. A total of 10 Ds1 elements had previously been sequenced from maize and a distant maize relative, Tripsacum. When a maximum likelihood network of genetic relationships is constructed for all 12 sequenced Ds1 elements, the 2 teosinte Ds1 elements are as distant from most maize Ds1 elements and from each other, as the maize Ds1 elements are from one another. Our new teosinte sequence data support the previous conclusion that Ds1 elements have been accumulating mutations independently since maize and Tripsacum diverged. We present a scenario for the origin of Ds1 elements.


Population genetics of transposable DNA elements. A Drosophila point of view. This paper is an attempt to bring together the various, dispersed data published in the literature on insertion polymorphism of transposable elements from various kinds of populations (natural populations, laboratory strains, isofemale and inbred lines). Although the results deal mainly with Drosophila, data on other organisms have been incorporated when necessary to illustrate the discussion. The data pertinent to the regions of insertion, the rates of transposition and excision, the copy number regulation, and the degree of heterozygosity were analysed in order to be confronted with the speculations made with various theoretical models of population biology of transposable elements. The parameters of these models are very sensitive to the values of the transposable element characteristics estimated on populations, and according to the difficulties of these estimations (population not at equilibrium, particular mutations used to estimate the transposition and excision rates, trouble with the in situ technique used to localize the insertions, undesired mobilization of TEs in crosses, spontaneous genome resetting, environmental effects, etc.) it cannot be decided accurately which model better accounts for the population dynamics of these TEs. Tendencies, however, emerge in Drosophila: the copia element shows evidence for deficiency of insertions on the X chromosomes, a result consistent with selection against mutational effects of copia insertions; the P element repartition does not significantly deviate from the neutral assumption, in spite of a systematic copy number of insertions higher on the X than on the autosomes. Data on other elements support either the neutral model of TE containment, neither of the two models, or both. Prudence in conclusion should then be de rigueur when dealing with such kind of data. Finally the potential roles of TEs in population adaptation and evolution are discussed.


Natural genetic engineering in evolution. The results of molecular genetics have frequently been difficult to explain by conventional evolutionary theory. New findings about the genetic conservation of protein structure and function across very broad taxonomic boundaries, the mosaic structure of genomes and genetic loci, and the molecular mechanisms of genetic change all point to a view of evolution as involving the rearrangement of basic genetic motifs. A more detailed examination of how living cells restructure their genomes reveals a wide variety of sophisticated biochemical systems responsive to elaborate regulatory networks. In some cases, we know that cells are able to accomplish extensive genome reorganization within one or a few cell generations. The emergence of bacterial antibiotic resistance is a contemporary example of evolutionary change; molecular analysis of this phenomenon has shown that it occurs by the addition rearrangement of resistance determinants and genetic mobility systems rather than by gradual modification of pre-existing cellular genomes. In addition, bacteria and other organisms have intricate repair systems to prevent genetic change by sporadic physicochemical damage or errors of the replication machinery. In their ensemble, these results show that living cells have (and use) the biochemical apparatus to evolve by a genetic engineering process. Future research will reveal how well the regulatory systems integrate genomic change into basic life processes during evolution.


Quantitative determination by ESR of the arylaminyl free radical during the reaction of N,N,N',N'-tetramethyl-p-phenylenediamine with oxyhemoglobin. Aromatic amines with electron-donating substituents are directly activated by pure oxyhemoglobin with formation of ferrihemoglobin. Of these xenobiotics the N-alkylated p-phenylenediamines are particularly active. With N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) cooxidation with oxyhemoglobin was observed by ESR spectroscopy with formation of the arylaminyl free radical (TMPD+*). Since the radical is rapidly reduced by ferrohemoglobin, a catalytic cycle of ferrihemoglobin formation is sustained with initially very low steady-state concentrations of the radical, e.g. below 0.1%. Ferrihemoglobin is also able to oxidize TMPD to the radical, hence the steady-state concentration of TMPD+* rises with increasing ferrihemoglobin. Radicals of the Wurster's type tend to disproportionate at high rates generating reactive quinonediiminium cations which oxidize and arylate cellular thiols like GSH and protein SH groups. Because the disproportionation rate depends on the square of the radical concentration, quenching of the radicals by ferrohemoglobin to protect cellular thiols will be effective as long as the capacity of the methemoglobin reductase system is not overwhelmed. The results indicate that erythrocytes may play a critical role in activation and detoxication of p-phenylenediamines.


Generation of singlet oxygen and hydroxyl radical from sodium chlorite and lactic acid. Reperfusion of ischemic tissue is associated with the formation of hydroxyl radical (OH.). In this report, a novel mechanism for (OH.) generation from (1O2) is proposed based on the experimental evidence from the present study. A number of experiments were performed which conclusively demonstrated the formation of 1O2 from the reaction of lactic acid and hypohalite radical. Singlet oxygen attacks the unsaturated olefinic derivatives, which are also formed during reperfusion of ischemic tissue. The reaction between 1O2 and olefinic compounds produces hydroperoxides, which ultimately form OH. radical. The validity of the above mechanism of OH. radical formation is warranted from our experimental results.


Superoxide anion scavenging capacity measured by a polarographic method. Comparison with a colourimetric method. A polarographic method to assess the scavenging capacity of a molecule for O2-. is proposed. This method is based on the fact that O2-. is not detected by the Clark electrode and that a scavenger competes with spontaneous dismutation of O2-. So, the reduction of O2 into O2-. and the decomposition of H2O2 by catalase, releasing O2, show a biphasic kinetic. Various kinetic parameters can be used to calculate the nmol of O2-. scavenged and also supply data on the reaction mechanisms (oxidation or reduction of O2-.) involved in scavenging. This method presents several other advantages: scavenging capacity can be assayed without added indicators which themselves behave as scavengers (as demonstrated for NBT), the presence of scavengers which interfere with the O2-. generating system (xanthine-xanthine oxidase) does not invalidate the measurements made.


The transition to a nursing home: meeting the family's needs. Family members face their own transition when a loved one enters a nursing home. The lack of preparation for the experience of admission to a nursing home, as represented by these family members, indicates there is a need for nursing interventions targeted to the family before the admission of a loved one to the nursing home. The program could address information and problem solving, as well as provide emotional support. The day of admission is too late to prepare for this experience. Access to families occurs before any admission to LTCFs. Nurses in acute care and home care are in a position to inform, assist, and advocate for families in this decision-making and admission process. The family members we questioned have provided some of the content for an educational preparation program that may be useful to all families. The responses also indicate that each family will have its own concerns and functional relationships that would alter specific content. Maslow's framework could aid the identification of needs and direct the specific interventions to empower the family to cope with this transition. A few guidelines have been suggested in this article to stimulate discussion about the family's transition to the nursing home. Appraisal of a family's perceptions about the use of nursing homes may alert the nurse to potential conflicts and areas of uncertainty. These assessments provide direction for family interventions that may alleviate the extent of uncertainty and conflict before the admission and serve as ongoing family-centered activity in the nursing home. The view of this experience as a family transition also supports the concept of continuity of care through nursing interventions.


Human papillomavirus type 16 found in primary transitional cell carcinoma of the Bartholin's gland and in a lymph node metastasis. We report a case of primary transitional cell carcinoma of the Bartholin's gland and its lymph node metastasis that contained HPV 16 sequences by polymerase chain reaction. The physical state of HPV 16 DNA in the primary cancer was investigated by Southern blot analysis which showed the presence of the episomal form of viral DNA. Our findings of HPV 16 DNA in the transitional cell carcinoma of the Bartholin's gland and its metastasis would indicate that both tumors arose from a single clonal event, thus providing evidence that the HPV 16 may have an oncogenic potential in this rare malignancy even in the episomal state.


Sexuality and aged women in nursing homes. In the face of overwhelming evidence that sexuality is essential to health and identity, society continues to make the aged sexually invisible. Despite all evidence that sexuality in all its forms is essential to health and identity, society continues to make the aged sexually invisible; some aged people continue to suffer guilt for having sexual feelings or acting sexually, and many aged people internalize the misconception that they are asexual. Aged women, in the main, have had their sexuality defined as being dependent on males and youthful beauty. Pfeiffer, cited in Reinzo, points out that as we age "sexual needs may not only be continuing but actually heightened due to losses in other areas of life." Elderly women ache for closeness, touch, and intimacy, but may be afraid to reach out to other women in this way. They have often lost control over much of their lives, and the only pleasure available to them may be self-pleasuring and fantasy, but guilt, lack of privacy, and fear of being "caught" remove this option. Their self-image and self-esteem are diminished. Women reacting to a definition imposed on them forfeit the pleasures of wholeness. The solution will be found when they assert their rights as individuals and claim their bodies as their own. Before elderly women can feel and be treated as fully human, it must be recognized that to be fully human is to be fully sexual, whatever our age. Gerontologic nurses who hold ageist views of elderly women's sexuality are not providing holistic care. It is not possible to provide care that aims at maximizing potential, independence, and control, while denying or ridiculing a "core" aspect of identity.(ABSTRACT TRUNCATED AT 250 WORDS)


Malignant placental site trophoblastic tumor associated with placental abruption, fetal distress, and elevated CA-125. The second pregnancy of 27-year-old woman, gravida 2, para 2 was complicated by a low alpha-fetoprotein and symptoms of chronic placental abruption. She delivered by cesarean section at 35 weeks for fetal distress at which time a biopsy of the uterus revealed a placental site trophoblastic tumor (PSTT). She rapidly developed intraabdominal spread of the neoplasm which did not respond to chemotherapy and she died 10 weeks later. Her CA-125 was elevated to 5360 mu/ml and this decreased after hysterectomy. This patient is reported to highlight a very malignant course of PSTT that was associated with a live-born male infant.


Primary biliary carcinoma with metastasis to the ovary. The ovary is a relatively frequent site of metastasis from malignant neoplasia arising elsewhere in the body, the majority of these originating from the GI tract. The best known tumor of this type is signet-ring cell adenocarcinoma (Krukenberg tumor) of gastric origin. The gall bladder and bile ducts are rare sources of these metastases. Asymptomatic carcinoma of the cystic duct metastasizing to the ovary is extremely rare. We are reporting such a case in which the patient presented with no GI or hepatic symptoms. The cystic duct carcinoma was an incidental finding from routine and careful examination of the abdominal viscera.


Hepatic angiomyolipomas with a deceptive trabecular pattern and HMB-45 reactivity. We report two cases of giant hepatic angiomyolipoma with a prominent component of epithelioid smooth muscle cells exhibiting a distinctive trabecular arrangement. These cells possessed peripherally vacuolated and centrally condensed hyaline cytoplasm. The nuclei were eccentrically placed in the cytoplasm. Immunohistochemically, they expressed HMB-45 intensely in the central condensed cytoplasm and actin in a perimembranous fashion. Staining for desmin, myoglobin and vimentin was negative. HMB-45 may prove to be a sensitive marker for angiomyolipoma with epithelioid cells. Hepatocellular carcinoma and other hepatic tumours with polygonal clear cells can be readily distinguished by these means.


Epstein-Barr virus and interleukin-5 mRNA in acquired immunodeficiency syndrome-related lymphomas with eosinophilia. Patients infected with the human immunodeficiency virus are at increased risk for developing intermediate-grade and high-grade B-cell lymphomas that in many instances contain Epstein-Barr viral (EBV) DNA. Because interleukin-5 (IL-5), a potent stimulator of eosinophil growth and differentiation, has been detected recently in EBV-infected B-cells, we hypothesized that some acquired immunodeficiency syndrome-related lymphomas with EBV DNA also might contain eosinophilia and IL-5. After reviewing files entered into our archives during the past 3 years, we identified four cases of human immunodeficiency virus-associated, high-grade, B-cell lymphomas that also contained extensive infiltration by eosinophils. Cryopreserved DNA from two of these four cases was available for amplification by the polymerase chain reaction, and both cases yielded an easily identifiable, EBV-specific amplification product. From one of these cases we also were able to extract mRNA and perform messenger amplification phenotyping (MAPPING) for the detection of mRNA coding for IL-5. After reverse transcription of mRNA from this case to cDNA and amplification by the polymerase chain reaction, we identified an amplification product that co-migrated with IL-5-positive controls in an agarose gel. We conclude that some AIDS-related lymphomas are associated with eosinophilia and that the eosinophilia may be related to EBV infection and transcriptional activation of the IL-5 gene.


Macrophages (histiocytes) in various reactive and inflammatory conditions express different antigenic phenotypes. The purpose of this study was to determine whether human tissue macrophages (M phi s) in various inflammatory/reactive conditions express different immunophenotypes. Using a large panel of monoclonal antibodies to monocyte/M phi-related antigens and a frozen-section immunoperoxidase technique, the following conditions were studied: granulomatous inflammation of unknown etiology, sarcoidosis, cat-scratch fever, toxoplasmosis, Gaucher's disease, and juvenile xanthogranulomas. The results show that there is immunophenotypic variation of the M phi s among the various inflammatory/reactive conditions. For example, the M phi s in cat-scratch fever are nearly unique in the expression of the "early inflammation" antigen identified by antibody 27E10, and the M phi s in juvenile xanthogranulomas, unlike those in most of the other conditions, lacked the antigen detected by antibody 25F9. The M phi s in Gaucher's disease differed from those in the other disorders by the combined absence of CD11b, CD14, G16/1, CD1a, CD25, and CD30. The inflammatory/reactive M phi s also exhibited differences from those in "normal" tissues, namely, a tendency toward acquisition of the antigens identified by antibodies Mac 387 and G16/1 and the more uniform expression of the "activation" antigens CD25, CD30, and CD71. The antigenic variations described here probably reflect differences in antigenic stimuli and M phi function. In addition to the possible biologic implications, this M phi immunophenotypic diversity may have practical diagnostic applications.


In situ hybridization of mitochondrial DNA in the heart of a patient with Kearns-Sayre syndrome and dilatative cardiomyopathy. Previous studies have revealed cytochrome-c-oxidase-deficient cardiomyocytes and the 4,977 base pair deletion ("common deletion") of mitochondrial DNA (position 8,482-13,459) in the heart of a patient with dilatative cardiomyopathy and Kearns-Sayre syndrome. In the present investigation the co-localization of the enzymatic and genomic defects was studied. In situ hybridization of mitochondrial DNA (mtDNA) revealed different hybridization patterns in the cytochrome-c-oxidase-deficient cells: (1) a selective reduction of the hybridization signal with an mtDNA probe recognizing the common deletion, indicating predominance of the deleted over the nondeleted mtDNA molecules in the cytochrome-c-oxidase-deficient cells; (2) a reduced hybridization signal with different mtDNA probes, indicating depletion of mtDNA; and (3) normal hybridization signals with different probes in single cytochrome-c-oxidase-deficient cardiomyocytes. These results indicate that different mechanisms may co-exist in Kearns-Sayre syndrome and may lead to defective respiratory chain function. The question of the pathogenetic interrelationship is discussed.


Spontaneous superoxide generation by polymorphonuclear leukocytes isolated from patients with stable angina after physical exercise. The activation of circulating polymorphonuclear leukocytes was determined in terms of O2.- generation and elastase release in patients with stable angina (n = 12) and in control subjects (n = 8) after maximal physical exercise and after a 15-min recovery. There was no spontaneous O2.- formation under basal conditions in both groups of patients. On the contrary, there was significant formation of O2.- (p < 0.001) from patients with stable angina measured directly after exercise, along with a slight spontaneous O2.- formation in control subjects (p < 0.05). After recovery, the spontaneous polymorphonuclear leukocyte-O2.- formation decreased but was still present in the patients with stable angina, while in the healthy subjects these values returned to resting levels. The activation of polymorphonuclear leukocytes with phorbol 12-myristate 13-acetate enhanced O2.- formation both in healthy subjects and in patients with stable angina, with a lesser effect in the latter. Moreover, no differences were observed in polymorphonuclear leukocyte-stimulated O2.- formation during the protocol, both in the angina stable patients and healthy subjects. No changes were found in plasma elastase levels among stable angina patients nor in control subjects as a consequence of exercise or recovery. This study indicates there is an early activation of circulating polymorphonuclear leukocytes in terms of O2.- production in stable angina patients during maximal exercise, which is still present after a 15-min recovery. Such activation occurs without elastase release. However, in healthy subjects maximal exercise resulted in very little increase in neutrophil activation.


Myocardial inositol and sodium in diabetes. Although inhibition of Na(+)-K+ ATPase has been described in the diabetic heart, K+ loss from myocardium has not been observed in a canine model of mild diabetes. The finding of tissue Na+ accumulation and a potential relation to alteration of left ventricular inositol as observed in other tissues in diabetes form the basis of this investigation. Diabetes was induced with alloxan in three groups of male mongrel dogs who were studied after 1 yr. In the initial experiment the tissue compartment volumes, determined with intravenous 51Cr EDTA as a marker, were found to be normal. Calculated cell sodium was increased to 32.8 +/- 2.6 mEq/kg cell H2O vs 18.7 +/- 1.1 in controls (p < 0.01). Cell potassium in diabetes was normal. In the second group, myocardial polyols were analyzed by gas-liquid chromatography. Inositol was diminished in diabetes to 0.61 +/- 23 microM/g of left ventricle, vs the respective control levels of 1.9 +/- 0.57 microM/g (p < 0.02). Sorbitol concentration was unaltered. Left ventricular sodium increments were not associated with altered tissue calcium. In group III the hypothesis that inhibition of Na(+)-K+ ATPase in diabetes might not elicit the expected alteration of K+ transport was assessed during intracoronary infusion of acetyl strophanthidin. No difference in cation responses from control was observed. It is postulated that a change in the conformation of Na(+)-K+ ATPase, with high affinity sodium binding sites facing the intracellular compartment, may render sodium less releasable from cell membrane.


Receptor imaging by positron emission tomography and single-photon emission computed tomography. Positron emission tomography (PET) has been used primarily to measure regional brain metabolism and blood flow. Single-photon emission computed tomography (SPECT) also can be used to measure brain perfusion. Receptor imaging by PET and SPECT, however, offers distinctive advantages over the more established flow/metabolism imaging methods, including improved chemical specificity and improved sensitivity in detecting changes in disease. Radioligands are available for PET and SPECT imaging of many neuroreceptors, including the opiate receptor, the dopamine receptor, and the muscarinic cholinergic receptor. A new focus of interest is the imaging and quantification of presynaptic neurotransmitter reuptake sites.


[Monosymptomatic Melkersson-Rosenthal syndrome with subsequent vulvitis and perivulvitis granulomatosa]. We report on an 40-year-old woman with granulomatous facial swelling followed by vulvitis and perivulvitis granulomatosa. The characteristic histopathology with epitheloid cell granulomas was seen in samples from both the face and the vulva. By immunohistochemistry the lesions were characterized as consisting mainly of histiocytic and CD-30-positive T cells. The possible aetiology is discussed briefly.


[Eccrine syringofibroadenoma. Report of clinical aspects and histology of two cases with review of the literature]. Eccrine syringofibroadenoma is a rare benign neoplasm with differentiation towards eccrine ducts. Its recognition depends on the histopathological examination; it is to be differentiated mainly from fibroepithelial basal cell carcinoma. Two new cases which occurred in a 70-year-old woman and a 39-year-old woman are presented. Clinically the two neoplasms were each a solitary hyperkeratotic, partially oozing nodule. On microscopic examination they both showed proliferation of small neoplastic cells in a reticular pattern; immature or mature eccrine ductal structures were seen within them. The neoplastic cells in the two cases differed in their content of PAS-positive glycogen.


Preparation of [131I]lipiodol as a hepatoma therapeutic agent. An isotopic exchange method was used to label lipiodol with 131I. The labelling efficiency was > 92.5%, and the radiochemical purity of [131I]lipiodol was above 98% as determined by ITLC. The influencing factors e.g. the heating temperature, reaction time, pH and storage conditions were studied and the optimum conditions were determined. In a pilot study injecting [131I]lipiodol for the treatment of hepatoma, about 70% of hepatoma patients had a response to the treatment with a reduction of alpha-fetoprotein and decrease of hepatoma sizes. The overall median survival was 9 months (range 2-17 months).


Evaluation of desferal as a bifunctional chelating agent for labeling antibodies with Zr-89. Zirconium-desferal was prepared and analysed by TLC, NMR and u.v.-spectroscopy. The stoichiometry of the complex was found to be 1:1. Chelation of desferal, coupled to resin, with 88Zr appeared to be fast and almost quantitative in various buffer systems in a broad pH-range (4-7). A high in vitro stability of the zirconium-desferal complex was observed; less than 0.2% zirconium was lost within 24 h in plasma-solutions.


A universal water target loading system with direct in-target liquid level sensing. A reliable remote water target loading system has been designed and fabricated around the operation of a single pneumatic syringe dispenser that accesses one of two water reservoirs, filling one or more targets depending on the system configuration. For multiple radionuclide configuration, reservoirs are filled with 18O-enriched water for [18F]fluoride production, and natural abundance water for [13N]nitrate and [13N]nitrite production. When actuated, the system withdraws a calibrated volume of water from a selected reservoir, and automatically dispenses that charge through a short transfer line to the appropriate target. A second actuation then forces the dispenser to purge itself of residual water by dispensing a charge of helium gas through the same line thus completing the transfer of water to the target volume. Direct liquid level sensing inside the target, utilizing the specific resistance response of water, signals the operator that the target is loaded. For single radionuclide configuration, one or both reservoirs can be used with the same type of water, while dispensing is directed to a single target.


The in vitro profile of selected 14-membered azalides. The in vitro antimicrobial potency of 10-aza-9-deoxo-11-deoxyerythromycin A, the first member of a new class of macrolide antibiotic, was determined. Several other members of this family of azalide were prepared and similarly screened in order to begin to define the antibiotic potential of the class. The results indicate that the SAR for this structural type parallels that of other macrolides and that it offers no apparent benefit over known 15-membered azalides.


A signal-anchor sequence selective for the mitochondrial outer membrane. pOMD29 is a hybrid protein containing the NH2-terminal topogenic sequence of a bitopic, integral protein of the outer mitochondrial membrane in yeast, OMM70, fused to dihydrofolate reductase. The topogenic sequence consists of two structural domains: an NH2-terminal basic region (amino acids 1-10) and an apolar region which is the predicted transmembrane segment (amino acids 11-29). The transmembrane segment alone was capable of targeting and inserting the hybrid protein into the outer membrane of intact mitochondria from rat heart in vitro. The presence of amino acids 1-10 enhanced the rate of import, and this increased rate depended, in part, on the basic amino acids located at positions 2, 7, and 9. Deletion of a large portion of the transmembrane segment (amino acids 16-29) resulted in a protein that exhibited negligible import in vitro. Insertion of pOMD29 into the outer membrane was not competed by import of excess precursor protein destined for the mitochondrial matrix, indicating that the two proteins may have different rate-limiting steps during import. We propose that the structural domains within amino acids 1-29 of pOMD29 cooperate to form a signal-anchor sequence, the characteristics of which suggest a model for proper sorting to the mitochondrial outer membrane.


In vitro reactions of vacuole inheritance in Saccharomyces cerevisiae. Vacuole inheritance is temporally coordinated with the cell cycle and is restricted spatially to an axis between the maternal vacuole and the bud. The new bud vacuole is founded by a stream of vacuole-derived membranous vesicles and tubules which are transported from the mother cell into the bud to form the daughter organelle. We now report in vitro formation of vacuole-derived tubules and vesicles. In semi-intact cells, formation of tubulovesicular structures requires ATP and the proteins encoded by VAC1 and VAC2, two genes which are required for vacuole inheritance in vivo. Isolation of vacuoles from cell lysates before in vitro incubation reveals that formation of tubulovesicular structures requires cytosol as well as ATP. After forming tubulovesicular structures, isolated vacuoles subsequently increase in size. Biochemical assays reveal that this increase results from vacuole to vacuole fusion, leading to mixing of organellar contents. Intervacuolar fusion is sensitive to the phosphatase inhibitors microcystin-LR and okadaic acid, suggesting that protein phosphorylation/dephosphorylation reactions play a role in this event.


Primary structure of an apical protein from Xenopus laevis that participates in amiloride-sensitive sodium channel activity. High resistance epithelia express on their apical side an amiloride-sensitive sodium channel that controls sodium reabsorption. A cDNA was found to encode a 1,420-amino acid long polypeptide with no signal sequence, a putative transmembrane segment, and three predicted amphipathic alpha helices. A corresponding 5.2-kb mRNA was detected in Xenopus laevis kidney, intestine, and oocytes, with weak expression in stomach and eyes. An antibody directed against a fusion protein containing a COOH-terminus segment of the protein and an antiidiotypic antibody known to recognize the amiloride binding site of the epithelial sodium channel (Kleyman, T. R., J.-P. Kraehenbuhl, and S. A. Ernst. 1991. J. Biol. Chem. 266:3907-3915) immunoprecipitated a similar protein complex from [35S]methionine-labeled and from apically radioiodinated Xenopus laevis kidney-derived A6 cells. A single integral of 130-kD protein was recovered from samples reduced with DTT. The antibody also cross-reacted by ELISA with the putative amiloride-sensitive sodium channel isolated from A6 cells (Benos, D. J., G. Saccomani, and S. Sariban-Sohraby. 1987. J. Biol. Chem. 262:10613-10618). Although the protein is translated, cRNA injected into oocytes did not reconstitute amiloride-sensitive sodium transport, while antisense RNA or antisense oligodeoxynucleotides specific for two distinct sequences of the cloned cDNA inhibited amiloride-sensitive sodium current induced by injection of A6 cell mRNA. We propose that the cDNA encodes an apical plasma membrane protein that plays a role in the functional expression of the amiloride-sensitive epithelial sodium channel. It may represent a subunit of the Xenopus laevis sodium channel or a regulatory protein essential for sodium channel function.


Localization of inositol 1,4,5-trisphosphate receptor-like protein in plasmalemmal caveolae. Activation of various receptors by extracellular ligands induces an influx of Ca2+ through the plasma membrane, but its molecular mechanism remains elusive and seems variable in different cell types. In the present study, we utilized mAbs generated against the cerebellar type I inositol 1,4,5-trisphosphate (InsP3) receptor and performed immunocytochemical and immunochemical experiments to examine its localization in several non-neuronal cells. By immunogold electron microscopy of ultrathin frozen sections as well as permeabilized tissue specimens, we found that a mAb to the type I InsP3 receptor (mAb 4C11) labels the plasma membrane of the endothelium, smooth muscle cell and keratinocyte in vivo. Interestingly, the labeling with the antibody was confined to caveolae, smooth vesicular inpocketings of the plasma membrane. The reactive protein, with an M(r) of 240,000 by SDS-PAGE, could be biotinylated with a membrane-impermeable reagent, sulfo-NHS-biotin, in intact cultured endothelial cells, and recovered by streptavidin-agarose beads, which result further confirmed its presence on the cell surface. The present findings indicate that a protein structurally homologous to the type I InsP3 receptor is localized in the caveolar structure of the plasma membrane and might be involved in the Ca2+ influx.


Protein kinase C activation antagonizes melatonin-induced pigment aggregation in Xenopus laevis melanophores. The pineal hormone, melatonin (5-methoxy N-acetyltryptamine) induces a rapid aggregation of melanin-containing pigment granules in isolated melanophores of Xenopus laevis. Treatment of melanophores with activators of protein kinase C (PKC), including phorbol esters, mezerein and a synthetic diacylglycerol, did not affect pigment granule distribution but did prevent and reverse melatonin-induced pigment aggregation. This effect was blocked by an inhibitor of PKC, Ro 31-8220. The inhibitory effect was not a direct effect on melatonin receptors, per se, as the slow aggregation induced by a high concentration of an inhibitor of cyclic AMP-dependent protein kinase (PKA), adenosine 3',5'-cyclic monophosphothioate, Rp-diastereomer (Rp-cAMPS), was also reversed by PKC activation. Presumably activation of PKC, like PKA activation, stimulates the intracellular machinery involved in the centrifugal translocation of pigment granules along microtubules. alpha-Melanocyte stimulating hormone (alpha-MSH), like PKC activators, overcame melatonin-induced aggregation but this response was not blocked by the PKC inhibitor, Ro 31-8220. This data indicates that centrifugal translocation (dispersion) of pigment granules in Xenopus melanophores can be triggered by activation of either PKA, as occurs after alpha-MSH treatment, or PKC. The very slow aggregation in response to inhibition of PKA with high concentrations of Rp-cAMPS, suggests that the rapid aggregation in response to melatonin may involve multiple intracellular signals in addition to the documented Gi-mediated inhibition of adenylate cyclase.


Mapping of myogenin transcription during embryogenesis using transgenes linked to the myogenin control region. During vertebrate embryogenesis, the muscle-specific helix-loop-helix protein myogenin is expressed in muscle cell precursors in the developing somite myotome and limb bud before muscle fiber formation and is further upregulated during myogenesis. We show that cis-acting DNA sequences within the 5' flanking region of the mouse myogenin gene are sufficient to direct appropriate temporal, spatial, and tissue-specific transcription of myogenin during mouse embryogenesis. Myogenin-lacZ transgenes trace the fate of embryonic cells that activate myogenin transcription and suggest that myogenic precursor cells that migrate from the somite myotome to the limb bud are committed to a myogenic fate in the absence of myogenin transcription. Activation of a myogenin-lacZ transgene can occur in limb bud explants in culture, indicating that signals required for activation of myogenin transcription are intrinsic to the limb bud and independent of other parts of the embryo. These results reveal multiple populations of myogenic precursor cells during development and suggest the existence of regulators other than myogenic helix-loop-helix proteins that maintain cells in the early limb bud in the myogenic lineage.


Bilateral retinal and brain tumors in transgenic mice expressing simian virus 40 large T antigen under control of the human interphotoreceptor retinoid-binding protein promoter. We have previously shown that postnatal expression of the viral oncoprotein SV40 T antigen in rod photoreceptors (transgene MOT1), at a time when retinal cells have withdrawn from the mitotic cycle, leads to photoreceptor cell death (Al-Ubaidi et al., 1992. Proc. Natl. Acad. Sci. USA. 89:1194-1198). To study the effect of the specificity of the promoter, we replaced the mouse opsin promoter in MOT1 by a 1.3-kb promoter fragment of the human IRBP gene which is expressed in both rod and cone photoreceptors during embryonic development. The resulting construct, termed HIT1, was injected into mouse embryos and five transgenic mice lines were established. Mice heterozygous for HIT1 exhibited early bilateral retinal and brain tumors with varying degrees of incidence. Histopathological examination of the brain and eyes of three of the families showed typical primitive neuroectodermal tumors. In some of the bilateral retinal tumors, peculiar rosettes were observed, which were different from the Flexner-Wintersteiner rosettes typically associated with human retinoblastomas. The ocular and cerebral tumors, however, contained Homer-Wright rosettes, and showed varying degrees of immunoreactivity to antibodies against the neuronal specific antigens, synaptophysin and Leu7, but not to antibodies against photoreceptor specific proteins. Taken together, the results indicate that the specificity of the promoter used for T antigen and/or the time of onset of transgene expression determines the fate of photoreceptor cells expressing T antigen.


M-CSF (monocyte colony stimulating factor) and M-CSF receptor expression by breast tumour cells: M-CSF mediated recruitment of tumour infiltrating monocytes? Infiltrating immune cells in 30 primary human epithelial breast tumours were studied using specific anti-CD3 (T cells), anti-CD68 (macrophages), anti-CD57 (NK cells), and an anti-pan-B cell antibody (L26). The majority of tumour infiltrating inflammatory cells are T cells (40-50%) and monocytes/macrophages (15-35%). The macrophage specific chemo-attractant and growth factor CSF-1 is detected by immunohistochemical techniques (IHC) at the level of invasive breast cancer cells in 46/50 tumours but not at the level of in-situ (pre-invasive) cancer. A mosaic staining pattern was usually observed, with a very high expression in areas of obvious stromal invasion (90% cells positive) and absent or trace staining in intraductal carcinoma. Macrophages and plasma cells are equally intensely positive. In-situ hybridisation experiments confirm the production of CSF-1 (mRNA) by tumour cells and show the same pattern of expression. Expression of the CSF-1 receptor protein (fms) was also observed by IHC in 41/48 invasive tumours, albeit at weaker intensities than in tumour infiltrating monocytes/macrophages. A concomitant expression of both CSF-1 and fms in in-situ carcinoma was never seen (n = 14). It is therefore proposed that the associated expression of CSF-1 and its receptor may be linked to the invasive potential of breast cancer, the monocytic infiltrate being an indication of the quantitative importance of CSF-1 production by the tumour.


Pathogenesis of central nervous system lesions in visna: cell-mediated immunity and lymphocyte subsets in blood, brain and cerebrospinal fluid. There are several indications that central nervous system (CNS) lesions in visna are immune-mediated and that cell-mediated immunity (CMI) may be of importance in the initiation of the lesions. To study the role of CMI in the pathogenesis of CNS lesions, five sheep were infected by intracerebral inoculation with visna virus and observed for 1 year. The following parameters were monitored at regular intervals: (1) neutralizing and ELISA antibodies; (2) visna virus-specific stimulation of lymphocytes from peripheral blood; (3) lymphocyte subpopulations in peripheral blood, cerebrospinal fluid (CSF) and brain at sacrifice. The CNS lesions were graded and compared with other parameters. The time course and titers of antibodies did not correlate with the severity of CNS lesions whereas the CMI did, indicating that CMI may play an important role in lesion development. The correlation of the number of CD8-positive cells in the CSF with the severity of lesions and the reversed ratio of CD4/CD8-positive cells in the diffusely infiltrated neuroparenchyma indicates that the CD8-positive T lymphocyte may be an important effector cell in the induction of CNS lesions.


Peripheral nervous system demyelination from systemic transfer of experimental allergic neuritis serum. The ability of systemically transferred experimental allergic neuritis (EAN) serum to produce EAN lesions in recipient animals was studied. Seventeen Lewis rats received five daily 1-ml intraperitoneal (i.p.) injections of sera from rabbits with EAN induced with bovine myelin/complete Freund's adjuvant (CFA). Another 17 rats received similar injections of sera from rabbits inoculated with CFA alone. On day 0 (the first day of i.p. injections), all rats were injected in the proximal tibial branch of the right sciatic nerve with a single 10-microliters injection of 0.03 M 5-hydroxytryptamine (5-HT) in sterile 0.15 M saline. Proximal tibial branches of left sciatic nerves received similar single injections of saline alone. Animals were then studied using electrophysiological and histological techniques. In all animals, intraneural saline injection had no significant effect upon nerve conduction. In the presence of circulating CFA serum, 5-HT injection caused a mild gradual decrease in amplitude ratio becoming maximal by day 17 (P < 0.005) and partially resolving by day 28. In contrast, in the presence of circulating EAN serum, 5-HT injection caused a more rapid and severe decrease in amplitude ratio becoming maximal by days 6-10 (P < 0.001 day 6; P < 0.0001 day 10) and completely resolving by day 28. Histological analysis of nerves injected with 5-HT in CFA serum-treated animals showed areas of mild demyelination, axonal degeneration and some fibre loss consistent with needle trauma. In contrast, 5-HT-injected nerves in animals administered EAN serum showed areas of marked cellular infiltration and severe demyelination in association with numerous debris-filled infiltrating cells.(ABSTRACT TRUNCATED AT 250 WORDS)


Effects of cyclosporine A on the hypothalamic-pituitary-adrenal axis and anterior pituitary interleukin-6 mRNA expression during chronic inflammatory stress in the rat. In the rat, adjuvant arthritis (AA) is an inflammatory joint disease associated with chronic stimulation of the hypothalamic-pituitary-adrenal (HPA) axis. We have investigated the effects of the immunosuppressive agent cyclosporine A (CsA) on plasma levels of adrenocorticotropin (ACTH) and corticosterone (B), as well as on anterior pituitary proopiomelanocortin (POMC) and interleukin (IL)-6 mRNA accumulation in control and adjuvant-injected animals. In control animals, CsA reduced basal anterior pituitary POMC and IL-6 mRNA and decreased plasma levels of ACTH and B. Adjuvant-injected animals that were treated with CsA showed no clinical signs of AA. Moreover, CsA inhibited the arthritis-induced increases in pituitary POMC and IL-6 mRNA levels and in circulating ACTH and B. In vitro, CsA reduced the POMC mRNA content of cultured anterior pituitary cells and diminished the stimulatory effects of corticotropin-releasing hormone (CRH) on POMC mRNA expression and ACTH secretion from these cells. These data indicate that CsA has a direct action on the HPA axis and also reduces the activation of the HPA axis seen in chronic inflammatory arthritis.


Kappa opioid binding sites on the R1.1 murine lymphoma cell line: sensitivity to cations and guanine nucleotides. The present study describes the characterization of an opioid binding site on membranes prepared from the R1.1 cell line, a murine thymoma. Specific (-)[3H]bremazocine binding was saturable, stereoselective, and limited to a single high affinity binding site with a Kd value of 15.2 +/- 1.6 pM and a Bmax value of 54.8 +/- 6.0 fmol/mg of protein. The kappa-selective alkaloids and dynorphin peptides inhibited (-)[3H]bremazocine binding with Ki values of less than 1 nM, in contrast to mu- and delta-selective ligands. The high affinity of this site for alpha-neo-endorphin and U50,488 suggests that this kappa opioid binding site resembles the kappa 1b subtype. NaCl, as well as other mono- and divalent cations, inhibited (-)[3H]bremazocine binding. In the presence of NaCl, the nucleotides GTP, GDP, and the nonhydrolyzable analog guanylyl-5'-imidodiphosphate (Gpp(NH)p) also decreased (-)[3H]bremazocine binding, suggesting that this kappa opioid binding site is coupled to a G-protein. In summary, R1.1 cells possess a single high affinity kappa opioid receptor that shares many properties with brain kappa 1b opioid receptors.


Oxygen modulates prostacyclin synthesis in ovine fetal pulmonary arteries by an effect on cyclooxygenase. Prostacyclin (PGI2) plays an integral role in O2 mediation of pulmonary vasomotor tone in the fetus and newborn. We hypothesized that O2 modulates PGI2 synthesis in vitro in ovine fetal intrapulmonary arteries, with decreasing O2 causing attenuated synthesis. A decline in PO2 from 680 to 40 mmHg caused a 26% fall in basal PGI2 synthesis. PGI2 synthesis maximally stimulated by bradykinin, A23187, and arachidonic acid were also attenuated at low PO2, by 35%, 33%, and 35%, respectively. PGE2 synthesis was equally affected. In contrast, varying O2 did not alter PGI2 synthesis with exogenous PGH2, which is the product of cyclooxygenase and the substrate for prostacyclin synthetase. Prostaglandin-mediated effects of O2 on cAMP production were also examined. Decreasing PO2 to 40 mmHg caused complete inhibition of basal cAMP production, whereas cAMP production stimulated by exogenous PGI2 was not affected. In parallel studies of mesenteric arteries, PGI2 synthesis and cAMP production were enhanced at low O2. Thus, PGI2 synthesis in fetal intrapulmonary arteries is modulated by changes in O2, with decreasing O2 causing attenuated synthesis. This process is due to an effect on cyclooxygenase activity, it causes marked parallel alterations in cAMP production, and it is specific to the pulmonary circulation.


Lipolytic catecholamine resistance due to decreased beta 2-adrenoceptor expression in fat cells. The existence of lipolytic beta-adrenoceptor (BAR) resistance was investigated in vivo and in isolated abdominal subcutaneous adipocytes in 65 healthy and drug-free subjects. The concentration of isoprenaline (nonselective BAR agonist) causing half-maximum lipolysis effect (ED50) varied bimodally and 10(6)-fold between individuals but was almost constant in the same subject when measured two times at rest or before and 30 min after exercise. The subjects were categorized as having either high or low isoprenaline sensitivity. The former group had a 50% reduced in vivo lipolytic response to exercise and mental stress, despite a 50% increased plasma noradrenaline response (P < 0.01) and a 350% increased plasma adrenaline response (P < 0.02). In fat cells the lipolytic ED50 values for noradrenaline and terbutaline (BAR2 agonist) were 10 times lower (P < 0.001) in low-sensitive subjects, but the maximum lipolytic actions of these agents (and of isoprenaline) were similar in both groups. The action on lipolysis of dobutamine (BAR1 agonist), forskolin (stimulating adenylate cyclase), dibutyryl cyclic AMP (activating protein kinase), clonidine (alpha 2-adrenergic agonist), or phenyl isopropyladenosine (adenosine receptor agonist) were almost identical in high- and low-sensitivity subjects. ED50 for isoprenaline correlated with ED50 for terbutaline (r = 0.75), but not with ED50 for dobutamine. In high-sensitivity subjects the number of BAR2 was almost three-fold increased (P < 0.002) and the steady-state adipocyte mRNA level for BAR2 was sixfold increased (P < 0.005). BAR2 affinity as well as BAR1 number, affinity and mRNA expression were similar in both groups. In 11 cholecystectomy patients (otherwise healthy) lipolytic ED50 for beta agonists correlated in omental and subcutaneous fat cells (r = 0.85 for isoprenaline; r = 0.95 for terbutaline). In conclusion, lipolytic resistance to catecholamines is present in vivo in apparently healthy subjects due to reduced expression of BAR2 in adipocytes.


Sequence analyses of three immunoglobulin G anti-virus antibodies reveal their utilization of autoantibody-related immunoglobulin Vh genes, but not V lambda genes. Accumulated sequence analyses of the antibody repertoire have revealed that most autoantibodies and developmentally regulated antibodies share a small set of germline Ig-variable region (V) genes. The findings have prompted speculation that certain autoantibodies are of developmental importance and may be instrumental in maintaining homeostasis of the adult antibody repertoire. In order to evaluate this hypothesis critically, it is first necessary to determine the V gene usage in human antibodies against foreign substances. Unfortunately, only a few such antibodies have had their heavy and light chains characterized. To rectify the situation, we adapted the anchored polymerase chain reaction to clone and analyze rapidly the expressed V genes for three anti-virus IgG antibodies. The results show that all three heavy chain V (Vh) genes are highly homologous to the known autoantibody-related Vh genes. In contrast, two light chain V (VL) genes of the V lambda 1 subgroup are similar to a non-autoantibody-related germline V lambda 1 gene. Taken together with the reported Vh and VL sequences of several antibodies against viruses and bacteria, the data show that many antipathogen antibodies may use the same small set of Vh genes that encode autoantibodies, but diverse VL genes that are distinct from autoantibody-related VL genes. Thus, only a small portion of the potentially functional germline Vh genes are used recurrently to generate most antibodies in a normal antibody repertoire, regardless of their reactivities with either self or non-self.


Cyclic adenosine monophosphate prevents the glucocorticoid-mediated inhibition of insulin gene expression in rodent islet cells. Dexamethasone negatively regulates insulin gene expression in HIT-15 cells. In vivo, however, an excess of glucocorticoids results in an increase in insulin biosynthesis and peripheral hyperinsulinemia. To resolve this contradiction, we have studied the effects of dexamethasone in primary rat islet cells. We show here that dexamethasone decreases insulin mRNA levels in single islet cells, as in HIT-15 cells, but does not affect these levels in reaggregated islet cells and increases them in intact islets of Langerhans. Because cAMP is an important regulator of insulin gene expression and intracellular cAMP content may be decreased in single beta cells, we investigated whether cAMP could prevent the inhibitory effect of dexamethasone on insulin mRNA levels. In the presence of cAMP analogues, the inhibitory action of dexamethasone was not only prevented, but insulin mRNA increased to levels comparable to those observed when cAMP analogues were used alone. We conclude that the insulin gene is negatively regulated by dexamethasone in single islet cells, but that other factors such as cAMP prevent this effect when the native environment of islet cells is preserved. Our results indicate that insulin gene regulation is influenced by cell to cell contacts within the islet, and that intracellular cAMP levels might be influential in this regulation.


Role of protein kinase C in parathyroid hormone stimulation of renal 1,25-dihydroxyvitamin D3 secretion. PTH is a major regulator of renal proximal tubule 1,25(OH)2D3 biosynthesis. However, the intracellular pathways involved in PTH activation of the mitochondrial 25-hydroxyvitamin D3-1 alpha-hydroxylase (1-OHase) remain unknown. PTH can activate both the adenylate cyclase/protein kinase A (PKA) and the plasma membrane phospholipase C/protein kinase C (PKC) pathways. The present study was undertaken to determine whether PKC may mediate PTH activation of renal 25-hydroxyvitamin D3-1 alpha-hydroxylase activity. Rat PTH 1-34 fragment in vitro translocated PKC activity from cytosolic to soluble membrane fraction from freshly prepared rat proximal tubules. Physiologic concentrations (10(-11)-10(-10) M) of rat PTH 1-34 fragment increased PKC translocation three- to fourfold while PKA activity ratio increased at PTH 10(-7) M. PTH stimulation of PKC and PKA was reduced in the presence of staurosporine (10 nM) by 41 and 29%, respectively. Sangivamycin (10 and 50 microM) also reduced PTH-stimulated PKC translocation, but did not alter PKA activity ratio. In vitro perifusion of renal proximal tubules with PTH (10(-11) M) increased 1,25(OH)2D3 steady-state secretion two- to fourfold. Sangivamycin at the same concentration that inhibited PKC translocation by 52% completely inhibited PTH-stimulated 1,25(OH)2D3 secretion. The present studies indicate that the phospholipase C/PKC pathway may mediate PTH stimulation of mammalian renal proximal tubule 1,25(OH)2D3 secretion.