[Effects of phospholipid layer on the dynamic microstructure of phosphorylation domain of Ca(2+)-ATPase from sarcoplasmic reticulum prepared from rabbit skeletal muscle]. The effects of phospholipids bilayers imposed on the intramolecular dynamic microstructure of Ca(2+)-ATPase from rabbit skeletal muscle sarcoplasmic reticulum were studied with a nanosecond time-resolved fluorometer. Ca(2+)-ATPase was purified and reconstituted into vesicle membranes. The phosphorylation domain of Ca(2+)-ATPase was labeled with a fluorophore, N-(1-anilinonaphthyl-4) maleimide (ANM). The phospholipids surrounding the hydrophobic segment of Ca(2+)-ATPase were exchanged with phosphatidylcholines of shorter acyl chain length by lipid titration. The membrane viscosity was measured by fluorometry using 1, 6-diphenyl-1, 3, 5-hexatriene (DPH). The membrane viscosity decreased when the intrinsic phospholipids were titrated with phosphatidylcholine having shorter acyl chains, and accompanied with a concurrent decrease in Ca(2+)-ATPase activity. The replacement of native lipids caused an increase in the fluorescence wavelength of ANM-labeled Ca(2+)-ATPase vesicles (red shift). This result suggests a conformational change in which the phosphorylation domain becomes more hydrophilic. The anisotropy decay time was was analyzed as two components, the slower being attributed to the intramolecular oscillation of the phosphorylation domain. The half-decay time of ANM fluorescence anisotropy was 72 +/- 4 nsec in the control vesicles, 69 +/- 3 nsec in di (18: 1) PC, 61 +/- 4 nsec in di (16: 1) PC, 54 +/- 3 nsec in di (14: 1) PC, and 49 +/- 2 nsec in di (12: 0) PC-titrated vesicles. This result suggests that the submolecular oscillation of the phosphorylation domain of Ca(2+)-ATPase is limited by the physical properties of boundary phospholipids, and that changes in the phospholipids cause alterations in the molecular motion of this domain, destabilize Ca(2+)-ATPase and reduce its activity.


Autocrine inhibition of mitotic activity in cultured oligodendrocyte-type-2 astrocyte (O-2A) precursor cells. During development, oligodendrocytes are generated from a bipotential glial stem cell, the oligodendrocyte-type-2 astrocyte precursor (O-2A). O-2A cells are under the mitogenic influence of the platelet-derived growth factor (PDGF) released from type-1 astrocytes. In vitro experiments have shown that O-2A cells stimulated by PDGF are limited to a set number of divisions and then differentiate to oligodendrocytes by becoming unresponsive to the growth factor. In the healthy adult central nervous system, oligodendrocyte proliferation remains generally quiescent and is possibly under negative growth control. The view that O-2A lineage cells are capable of negatively regulating their own proliferation is supported by the demonstration that conditioned medium obtained from O-2A cultures inhibits their DNA synthesis. In addition to O-2A cells, the newly established CG4 cell line, a derivative of O-2A cells, was found to inhibit O-2A lineage cell proliferation. The antiproliferative activity was present in the media conditioned by CG4 cells that were expanded as undifferentiated O-2A precursors, as well as by CG4 cells induced to differentiate to nonproliferating oligodendrocytes. Moreover, the inhibitory activity was produced by CG4 cells (source cells) propagated by various mitogens. The inhibition of mitotic activity was nearly complete, dose-dependent, fully reversible, and exhibited when CG4 cells (test cells) were stimulated to divide by various mitogens, such as PDGF, basic fibroblast growth factor, or medium conditioned by the neuronal B104 cell line. The inhibition of proliferation was accompanied by the conversion of the phenotype of CG4 cells, from A2B5+/O4- precursors to A2B5-/O4+ pro-oligodendrocytes.(ABSTRACT TRUNCATED AT 250 WORDS)


Characteristics of fish glial cells in culture: possible implications as to their lineage. Regeneration of injured central nervous system axons is largely dependent on the response of the associated nonneuronal glial cells to injury. Glial cells of the mammalian central nervous system, unlike those of fish, are apparently not conducive to axonal regeneration. While the lineage of rat glial cells is well characterized and its role in the support or inhibition of regenerative growth is beginning to be understood, little is known about fish glial cells. Accordingly, glial cells in cultures of adult goldfish brain and of newly hatched goldfish larvae were studied in an attempt to establish their lineage. The cells were identified by means of indirect immunofluorescence, using antibodies against fish astrocytes and oligodendrocytes. The cell count in the cultures increased from a small number of cells at 24 h after plating to a large number of both astrocytes and oligodendrocytes after 1 week in culture. Both of these cell types had originated from proliferating cells, as shown by their uptake of tritiated thymidine and by the inhibition of cell proliferation by 5-fluoro-2'-deoxyuridine. Both astrocytes, i.e., glial fibrillary acidic protein-positive cells, and oligodendrocytes, i.e., 6D2-positive cells, were positively labeled also by A2B5 antibodies, which are known to label progenitors of type-2 astrocytes and oligodendrocytes in the rat optic nerve. The results suggest that A2B5 positive progenitor cells in the goldfish central nervous system, as in the rat optic nerve, might be a common progenitor of astrocytes and oligodendrocytes.


Response of microglial cells to experimental rat glioma. The response of indigenous CNS microglia to an experimentally induced glioma has been studied in rat brain using lectin histochemistry with the Griffonia simplicifolia B4-isolectin. The study was undertaken 2 weeks after tumor cell injection when tumor size was near maximal. Reactive microglial cells formed a dense band that surrounded most of the well-circumscribed tumor mass, and extended along the corpus callosum into the contralateral cerebral hemisphere. From the periphery inward, reactive microglia extended into the tumor tissue, where large numbers of them were found to be present as microglia-derived macrophages. The lectin stain, which also labels endothelial cells, revealed a highly vascularized tumor with ongoing neovascularization apparent as vascular sprouts. Moderate numbers of lectin-stained blood monocytes were localized primarily inside the vessel lumina. Our results show that microglial cells react to brain tumors; however, it remains to be determined whether the microglial response represents an active antitumor defense mechanism that could be manipulated during immunotherapeutic approaches.


CD4+ TCR alpha beta+ T-cell clones derived shortly after allogeneic bone marrow transplantation: theophyllamine and verapamil inhibit proliferation of functionally heterogeneous T-cells. CD4+ TCR alpha beta+ T-cell clones were prepared from three CML-patients 4-6 weeks after allogeneic bone marrow transplantation and the effects of theophyllamine and verapamil on clonal growth then assessed. Both drugs inhibited PHA-stimulated autocrine proliferation of clones as well as proliferation of clones dependent on exogenous growth factors. Inhibition was seen when using different accessory cells (PBM or BCL) during T-cell activation, and both for IL2- and IL4-dependent proliferation of previously activated T-cells. The isomer R-verapamil inhibited PHA-stimulated proliferation as well as IL2- and IL4-dependent T-cell proliferation. The drugs also inhibited proliferation of CD8+ T-cells. Although the T-cell clones were functionally heterogeneous and were derived from different patients and priming cultures, both drugs inhibited all clones investigated. However, the degree of inhibition varied between different clones.


The effect of liver macrophages on in vitro cytolytic activity of 5FU and FUdR on colon carcinoma cells: evidence of macrophage activation. While investigating the effects of 5-fluorouracil (5FU) and 5-fluoro-2'-deoxyuridine (FUdR) on the tumoricidal state of rat liver macrophages activated in vitro by means of liposome-encapsulated muramyl dipeptide (MDP), we observed that 5FU in combination with macrophages produced substantially higher extents of cytolytic activity on tumor cells than 5FU alone. In contrast, FUdR failed to produce this effect; rather, at relatively low FUdR concentrations, lytic activity in the presence of macrophages was even significantly diminished as compared with FUdR in the absence of macrophages. Both 5FU and FUdR were able to enhance the cytolytic activity of macrophages activated by liposome-encapsulated MDP. This finding indicates that, rather than inhibiting the activation of macrophages by liposomal MDP, 5FU can act as a stimulator of macrophage activation by itself. This is further supported by the observations that (i) in combination with 5FU, the secretion of TNF induced by liposomal MDP was synergistically enhanced and (ii) that a second treatment of macrophages with the drug, 24 h after the first, fails to produce increased macrophage cytotoxicity. Our results also show that neither 5FU nor FUdR are likely to unfavorably influence the induction of cytotoxic activity of the macrophages. Rather, combinations of 5FU or FUdR and liposomal MDP may result in an additive or synergistic tumoricidal effect.


An in vivo model for the experimental selection of drugs able to prevent immune complex glomerulonephritis. Polyclonal activation of lymphocytes and immune complex-mediated glomerular lesions were induced in C57Bl/6 mice by injecting bacterial lipopolysaccharide (LPS) twice a week for 2 weeks. The usefulness of such a model for in vivo evaluation of immunomodulatory and therapeutic effects of drugs, was investigated by treating mice with DIAM4, a cyclophosphazenic compound known to modulate polyclonal activation of lymphocytes and to prevent mouse lupus nephritis. Prevention of LPS-triggered lymphocyte polyclonal activation and glomerular lesions was observed in the DIAM4-treated mice. Such a model can be used conveniently to select compounds effective in the treatment of immune glomerulonephritis.


Inhibition of proliferation and differentiation of human B-lymphocytes by a biscoclaurine alkaloid. A biscoclaurine alkaloid, cepharanthine, is known to be a potent inhibitor of snake venom-induced hemolysis by interaction with the lipid bilayer of the membrane. The drug also interferes with the ion channel intracellularly. In this study, we examined the effect of cepharanthine on human B-cell functions. Small dense B-cells from tonsil samples were isolated using a Percoll density gradient from non-rosetted cells and were used as the target cells. Cepharanthine inhibited the proliferation of the lymphocytes and antibody production of human B-lymphocytes. The inhibitory effect of cepharanthine on the proliferation was caused by the arrest of the late G1 to S phase transition in the cell cycle. However, the mechanism of suppression of antibody formation remains unknown. These results suggest that cepharanthine acts on human B-cells as an immunomodulating agent.


A meta-analytic comparison of the effectiveness of smoking cessation methods. Meta-analysis was used to cumulate the results from 633 studies of smoking cessation, involving 71,806 subjects, that reported the proportion of successful quits. Self-care methods do not appear to be as effective as formal intervention methods. Instructional programs involving physicians were not more effective than other instructional programs. Conditioning-based techniques such as aversive methods had success rates similar to those of instructional methods, and among the instructional methods, those incorporating social norms and values were more successful than those relying solely on didactic approaches. Cumulation of quit rates from all available control groups indicated that, on average, 6.4% of the smokers could be expected to quit smoking without any intervention. This figure must be subtracted from the raw success rate to obtain the net success rate for each program. Directions for future research are discussed.


Mechanism of Streptococcus mutans glucosyltransferases: hybrid-enzyme analysis. Streptococcus mutans GS5 expresses three glucosyltransferases (GTFs): GTF-I and GTF-SI, which synthesize water-insoluble glucans in a primer-independent manner, and GTF-S, which is responsible for the formation of primer-dependent soluble glucan. The amino acid sequences of the GTF-I and GTF-S enzymes exhibit approximately 50% sequence identity. Various hybrid genes were constructed from the structural genes for the enzymes, and their products were analyzed. Three different approaches were used to construct the hybrid enzymes: (i) ligation of DNA fragments containing compatible endonuclease restriction sites of the two genes at homologous positions; (ii) in vivo recombination between the homologous regions of each gene; and (iii) random fusion of DNA fragments from each gene generated following exonuclease III digestion of tandemly arranged fragments corresponding to the two functional domains of each enzyme. Hybrid GTFs composed of the sucrose-binding domain of one enzyme (GTF-I or GTF-S) with the glucan-binding domain of the other synthesized insoluble glucan exclusively in the absence of primer dextran. Insoluble glucan synthesis by some, but not all, of the GTF-S:GTF-I chimeric enzymes was stimulated by primer dextran T10 addition. In addition, glucan binding by the former but not latter group of hybrid GTFs was demonstrated. These results suggest that the glucan-binding domain alone does not solely determine primer dependence or independence or the structure of the resulting glucan product, although this carboxyl-terminal domain containing direct repeating units does appear to play a significant role in primer dependence.


Inhibition of actin-tropomyosin activation of myosin MgATPase activity by the smooth muscle regulatory protein caldesmon. Caldesmon inhibition of actin-tropomyosin activation of myosin MgATPase activity was investigated. greater than 90% inhibition of ATPase activation correlated with 0.035-0.1 caldesmon bound per actin monomer over a wide range of conditions. Caldesmon inhibited sheep aorta actin-tropomyosin activation of skeletal muscle heavy meromyosin (HMM) by 85%, but had no effect on the binding affinity of HMM.ADP.Pi to actin. At ratios of 2 and 0.12 subfragment 1 (S1):1 actin, addition of caldesmon inhibited the ATPase activation by up to 95%, but did not alter the fraction of S1.ADP.Pi associated with actin-tropomyosin. We concluded that caldesmon inhibited actomyosin ATPase by slowing the rate-limiting step of the activation pathway. At concentrations comparable to the ATPase measurements, S1 displaced caldesmon from native thin filaments both in the absence (rigor) and the presence of MgATP. We therefore concluded that caldesmon could displace S1.ADP.Pi from actin-tropomyosin only under exceptional circumstances. An expressed mutant of caldesmon comprising just the C-terminal 99 amino acids bound actin 10 times weaker than whole caldesmon but otherwise inhibited actin-tropomyosin activation with the same potency and same mechanism as intact caldesmon. Thus, the entire inhibitory function of caldesmon resides in its extreme C terminus.


In vivo conversion of [3H]myoinositol to [3H]chiroinositol in rat tissues. We report here the in vivo conversion of [3H]myoinositol to [3H]chiroinositol. After labeling intraperitoneally with [3H]myoinositol for 3 days to reach radioisotope equilibrium in urine, [3H]chiroinositol was isolated from tissues and purified after 6 N HCl hydrolysis by two sequential paper chromatographies and high performance liquid chromatography (HPLC). Percent conversion of [3H]myoinositol to [3H]chiroinositol was highest in urine (36%), liver (8.8%), muscle (8.8%), and blood (7.6%) with intestine, brain, kidney, spleen, and heart decreasing in percentage from 2.8 to 0.7%. Labeling of other inositol isomers including scyllo-, neo-, and epi-, and mucoinositol was minimal, approximately 0.06% of [3H]myoinositol. Glucose was unlabeled, but glucuronate, the product of myoinositol oxidation, was labeled up to 1.5% of the [3H] myoinositol. Acid hydrolysates of combined inositol-containing phospholipids contain significant labeled chiroinositol. [3H]Phosphatidylinositols and [3H]glycosylphosphatidylinositols were extracted from liver, muscle, and blood, isolated by thin layer chromatography, and inositols purified by HPLC after acid hydrolysis. Percent conversion of [3H]myoinositol to [3H] chiroinositol was highest in blood (60.4%) followed by muscle (7.7%) and liver (2.2%).


Fluoride binding to the calcium ATPase of sarcoplasmic reticulum converts its transport sites to a low affinity, lumen-facing form. The sarcoplasmic reticulum CaATPase forms an inactive complex with fluoride (CaATPase-F), which in the absence of calcium reactivates very slowly (t1/2 approximately 40 h at 25 degrees C). Reactivation is greatly accelerated (greater than 10(3)) by calcium in the millimolar range provided it has access to luminal sites of the enzyme. Measurement of the calcium concentration dependence of the reactivation rate constant revealed a saturable effect with a midpoint of about 12 mM calcium. These results show that an effect other than phosphorylation can produce a greater than 10(3)-fold affinity decrease and reorientation of the calcium transport sites. At a fixed calcium concentration, reactivation became faster with increasing pH (pKa greater than 8), suggesting competition between Ca2+ and H+ for transport sites. CaATPase-F lacked the ability to bind calcium with high affinity or to form phosphorylated enzyme intermediate from Pi; it bound adenyl-5'-yl methylenediphosphonate more than 10-fold less strongly than control CaATPase, had numerous sulfhydryl groups with significantly different reactivity, and was notably less susceptible (more than 10-fold) to thermal inactivation compared with control Ca-ATPase. These results suggest that formation of Ca-ATPase-F involves significant structural changes.


Formation and structure of the C5b-7 complex of the lytic pathway of complement. The formation and structure of the complement cytolytic intermediary complex, C5b-7, were studied with the aim of determining the interactive regions of C5, C6, and C7. The structure of human complement component C5 was elucidated by the application of limited proteolysis which generated well characterized major polypeptide fragments of this molecule. Plasmin, thrombin, and kallikrein cleave C5b with greater facility than C5. The most useful cleavage of C5b was effected by plasmin because the fragmentation pattern was similar to the processing of C3b by factors H, I, and kallikrein. Plasmin hydrolyzes peptide bonds within the alpha'-chain of C5b, resulting in a four-chain fragment, C5c (M(r) = 142,000), and a single chain fragment, C5d (M(r) = 43,000). Circular dichroism spectroscopic analyses indicated that C5d is substantially richer in alpha-helical content than is C5c (27 versus 9%). Polyclonal antibodies directed against C5c blocked the interaction of C5b-6 with C7, whereas antibodies directed against C5d inhibited the binding of C5 with C3b. Chemical cross-linking using a cleavable radioiodinated photoreactive reagent revealed that both C6 and C7 associate preferentially with the alpha'-chain of C5b. The reversible interactions of C5 with C6, C7, and major polypeptide fragments derived from these were investigated with solid phase binding assays. The results indicate that the carboxyl-terminal domains of C6 and C7, which have cysteine-rich modules homologous to those found in factors H and I, have the capacity to link specifically with C5.


Control of microtubule dynamics and length by cyclin A- and cyclin B-dependent kinases in Xenopus egg extracts. In eukaryotic cells, the onset of mitosis involves cyclin molecules which interact with proteins of the cdc2 family to produce active kinases. In vertebrate cells, cyclin A dependent kinases become active in S- and pro-phases, whereas a cyclin B-dependent kinase is mostly active in metaphase. It has recently been shown that, when added to Xenopus egg extracts, bacterially produced A- and B-type cyclins associate predominantly with the same kinase catalytic subunit, namely p34cdc2, and induce its histone H1 kinase activity with different kinetics. Here, we show that in the same cell free system, both the addition of cyclin A and cyclin B changes microtubule behavior. However, the cyclin A-dependent kinase does not induce a dramatic shortening of centrosome-nucleated microtubules whereas the cyclin B-dependent kinase does, as previously reported. Analysis of the parameters of microtubule dynamics by fluorescence video microscopy shows that the dramatic shortening induced by the cyclin B-dependent kinase is correlated with a several fold increase in catastrophe frequency, an effect not observed with the cyclin A-dependent kinase. Using a simple mathematical model, we show how the length distributions of centrosome-nucleated microtubules relate to the four parameters that describe microtubule dynamics. These four parameters define a threshold between unlimited microtubule growth and the establishment of steady-state dynamics, which implies that well defined steady-state length distributions can be produced by regulating precisely the respective values of the dynamical parameters. Moreover, the dynamical model predicts that increasing catastrophe frequency is more efficient than decreasing the rescue frequency to reduce the average steady state length of microtubules. These theoretical results are quantitatively confirmed by the experimental data.


Cyclin A potentiates maturation-promoting factor activation in the early Xenopus embryo via inhibition of the tyrosine kinase that phosphorylates cdc2. We have produced human cyclin A in Escherichia coli and investigated how it generates H1 kistone kinase activity when added to cyclin-free extracts prepared from parthenogenetically activated Xenopus eggs. Cyclin A was found to form a major complex with cdc2, and to bind cdk2/Eg1 only poorly. No lag phase was detected between the time when cyclin A was added and the time when H1 histone kinase activity was produced in frog extracts, even in the presence of 2 mM vanadate, which blocks cdc25 activity. Essentially identical results were obtained using extracts prepared from starfish oocytes. We conclude that formation of an active cyclin A-cdc2 kinase during early development escapes an inhibitory mechanism that delays formation of an active cyclin B-cdc2 kinase. This inhibitory mechanism involves phosphorylation of cdc2 on tyrosine 15. Okadaic acid (OA) activated cyclin B-cdc2 kinase and strongly reduced tyrosine phosphorylation of cyclin B-associated cdc2, even in the presence of vanadate. 6-dimethylamino-purine, a reported inhibitor of serine-threonine kinases, suppressed OA-dependent activation of cyclin B-cdc2 complexes. This indicates that the kinase(s) which phosphorylate(s) cdc2 on inhibitory sites can be inactivated by a phosphorylation event, itself antagonized by an OA-sensitive, most likely type 2A phosphatase. We also found that cyclin B- or cyclin A-cdc2 kinases can induce or accelerate conversion of the cyclin B-cdc2 complex from an inactive into an active kinase. Cyclin B-associated cdc2 does not undergo detectable phosphorylation on tyrosine in egg extracts containing active cyclin A-cdc2 kinase, even in the presence of vanadate. We propose that the active cyclin A-cdc2 kinase generated without a lag phase from neo-synthesized cyclin A and cdc2 may cause a rapid switch in the equilibrium of cyclin B-cdc2 complexes to the tyrosine-dephosphorylated and active form of cdc2 during early development, owing to strong inhibition of the cdc2-specific tyrosine kinase(s). This may explain why early cell cycles are so rapid in many species.


Homology of the 74-kD cytoplasmic dynein subunit with a flagellar dynein polypeptide suggests an intracellular targeting function. In previous work we found cytoplasmic dynein to be a complex of two catalytic heavy chains and at least seven co-purifying polypeptides of unknown function. The most prominent of these is a 74-kD electrophoretic species which can be resolved as two to three bands by SDS-PAGE. We have now selected a series of overlapping rat brain cDNAs encoding the 74-kD species. The deduced sequence of a full-length cDNA predicts a 72,753 D polypeptide which includes the amino acid sequences of nine peptides determined by NH2-terminal microsequencing. PCR performed on first strand rat brain cDNA together with the sequence of a partially matching tryptic peptide indicated the existence of at least three isoforms of the 74-kD cytoplasmic dynein subunit. Comparison with known sequences revealed that the carboxyl-terminal half of the polypeptide is 26.4% identical and 47.7% similar to the product of the Chlamydomonas ODA6 gene, a 70-kD intermediate chain of flagellar outer arm dynein. Immunoblot analysis with a monoclonal antibody to the 74-kD species indicated a widespread tissue distribution, as expected for a cytoplasmic dynein subunit. Nonetheless, the antibody recognized a 67-kD species in ram sperm flagella and pig tracheal cilia, supporting the existence of distinct but related cytoplasmic and axonemal polypeptides in mammals. In view of evidence for a role for the ODA6 gene product in anchoring flagellar dynein to the A subfiber microtubule in the axoneme, we predict an analogous role for the 74-kD polypeptide, perhaps in mediating the interaction of cytoplasmic dynein with membranous organelles and kinetochores.


Arrangement of inner dynein arms in wild-type and mutant flagella of Chlamydomonas. We have used computer averaging of electron micrographs from longitudinal and cross-sections of wild-type and mutant axonemes to determine the arrangement of the inner dynein arms in Chlamydomonas reinhardtii. Based on biochemical and morphological data, the inner arms have previously been described as consisting of three distinct subspecies, I1, I2, and I3. Our longitudinal averages revealed 10 distinguishable lobes of density per 96-nm repeating unit in the inner row of dynein arms. These lobes occurred predominantly but not exclusively in two parallel rows. We have analyzed mutant strains that are missing I1 and I2 subspecies. Cross-sectional averages of pf9 axonemes, which are missing the I1 subspecies, showed a loss of density in both the inner and outer portions of the inner arm. Averages from longitudinal images showed that three distinct lobes were missing from a single region; two of the lobes were near the outer arms but one was more inward. Serial 24-nm cross-sections of pf9 axonemes showed a complete gap at the proximal end of the repeating unit, confirming that the I1 subunit spans both inner and outer portions of the inner arm region. Examination of pf23 axonemes, which are missing both I1 and I2 subspecies, showed an additional loss almost exclusively in the inner portion of the inner arm. In longitudinal view, this additional loss occurred in three separate locations and consisted of three inwardly placed lobes, one adjacent to each of the two radial spokes and the third at the distal end of the repeating unit. These same lobes were absent ida4 axonemes, which lack only the I2 subspecies. The I2 subspecies thus does not consist of a single dynein arm subunit in the middle of the repeating unit. The radial spoke suppressor mutation, pf2, is missing four polypeptides of previously unknown location. Averages of these axonemes were missing a portion of the structures remaining in pf23 axonemes. This result suggests that polypeptides of the radial spoke control system are close to the inner dynein arms.


Extragenic suppressors of paralyzed flagellar mutations in Chlamydomonas reinhardtii identify loci that alter the inner dynein arms. We have analyzed extragenic suppressors of paralyzed flagella mutations in Chlamydomonas reinhardtii in an effort to identify new dynein mutations. A temperature-sensitive allele of the PF16 locus was mutagenized and then screened for revertants that could swim at the restrictive temperature (Dutcher et al. 1984. J. Cell Biol. 98:229-236). In backcrosses of one of the revertant strains to wild-type, we recovered both the original pf16 mutation and a second, unlinked suppressor mutation with its own flagellar phenotype. This mutation has been identified by both recombination and complementation tests as a new allele of the previously uncharacterized PF9 locus on linkage group XII/XIII. SDS-PAGE analysis of isolated flagellar axonemes and dynein extracts has demonstrated that the pf9 strains are missing four polypeptides that form the I1 inner arm dynein subunit. The primary effect of the loss of the I1 subunit is a decrease in the forward swimming velocity due to a change in the flagellar waveform. Both the flagellar beat frequency and the axonemal ATPase activity are nearly wild-type. Examination of axonemes by thin section electron microscopy and image averaging methods reveals that a specific domain of the inner arm complex is missing in the pf9 mutant strains (see accompanying paper by Mastronarde et al.). When combined with other flagellar defects, the loss of the I1 subunit has synergistic effects on both flagellar assembly and flagellar motility. These synthetic phenotypes provide a screen for new suppressor mutations in other loci. Using this approach, we have identified the first interactive suppressors of a dynein arm mutation and an unusual bypass suppressor mutation.


The motile beta/IC1 subunit of sea urchin sperm outer arm dynein does not form a rigor bond. We used in vitro translocation and cosedimentation assays to study the microtubule binding properties of sea urchin sperm outer arm dynein and its beta/IC1 subunit. Microtubules glided on glass-absorbed sea urchin dynein for a period of time directly proportional to the initial MgATP2- concentration and then detached when 70-95% of the MgATP2- was hydrolyzed. Detachment resulted from MgATP2- depletion, because (a) perfusion with fresh buffer containing MgATP2- reconstituted binding and gliding, (b) microtubules glided many minutes with an ATP-regenerating system at ATP concentrations which alone supported gliding for only 1-2 min, and (c) microtubules detached upon total hydrolysis of ATP by an ATP-removal system. The products of ATP hydrolysis antagonized binding and gliding; as little as a threefold excess of ADP/Pi over ATP resulted in complete loss of microtubule binding and translocation by the beta/IC1 subunit. In contrast to the situation with sea urchin dynein, microtubules ceased gliding but remained bound to glass-absorbed Tetrahymena outer arm dynein when MgATP2- was exhausted. Cosedimentation assays showed that Tetrahymena outer arm dynein sedimented with microtubules in an ATP-sensitive manner, as previously reported (Porter, M.E., and K. A. Johnson. J. Biol. Chem. 258: 6575-6581). However, the beta/IC1 subunit of sea urchin dynein did not cosediment with microtubules in the absence of ATP. Thus, this subunit, while capable of generating motility, lacks both structural and rigor-type microtubule binding.


The alpha subunit of sea urchin sperm outer arm dynein mediates structural and rigor binding to microtubules. Glass-adsorbed intact sea urchin outer arm dynein and its beta/IC1 subunit supports movement of microtubules, yet does not form a rigor complex upon depletion of ATP (16). We show here that rigor is a feature of the isolated intact outer arm, and that this property subfractionates with its alpha heavy chain. Intact dynein mediates the formation of ATP-sensitive microtubule bundles, as does the purified alpha heavy chain, indicating that both particles are capable of binding to microtubules in an ATP-sensitive manner. In contrast, the beta/IC1 subunit does not bundle microtubules. Bundles formed with intact dynein are composed of ribbon-like sheets of parallel microtubules that are separated by 54 nm (center-to-center) and display the same longitudinal repeat (24 nm) and cross-sectional geometry of dynein arms as do outer doublets in situ. Bundles formed by the alpha heavy chain are composed of microtubules with a center-to-center spacing of 43 nm and display infrequent, fine crossbridges. In contrast to the bridges formed by the intact arm, the links formed by the alpha subunit are irregularly spaced, suggesting that binding of the alpha heavy chain to the microtubules is not cooperative. Cosedimentation studies showed that: (a) some of the intact dynein binds in an ATP-dependent manner and some binds in an ATP-independent manner; (b) the beta/IC1 subunit does not cosediment with microtubules under any conditions; and (c) the alpha heavy chain cosediments with microtubules in the absence or presence of MgATP2-. These results suggest that the structural binding observed in the intact arm also is a property of its alpha heavy chain. We conclude that whereas force-generation is a function of the beta/IC1 subunit, both structural and ATP-sensitive (rigor) binding of the arm to the microtubule are mediated by the alpha subunit.


Analysis of a developmentally regulated nuclear localization signal in Xenopus. The 289 residue nuclear oncoprotein encoded by the adenovirus 5 Ela gene contains two peptide sequences that behave as nuclear localization signals (NLS). One signal, located at the carboxy terminus, is like many other known NLSs in that it consists of a short stretch of basic residues (KRPRP) and is constitutively active in cells. The second signal resides within an internal 45 residue region of E1a that contains few basic residues or sequences that resemble other known NLSs. Moreover, this internal signal functions in injected Xenopus oocytes, but not in transfected Xenopus A6 cells, suggesting that it could be regulated developmentally (Slavicek et al. 1989. J. Virol. 63:4047). In this study, we show that the activity of this signal is sensitive to ATP depletion in vivo, efficiently directs the import of a 50 kD fusion protein and can compete with the E1a carboxy-terminal NLS for nuclear import. In addition, we have delineated the precise amino acid residues that comprise the second E1a NLS, and have assessed its utilization during Xenopus embryogenesis. Using amino acid deletion and substitution analyses, we show that the signal consists of the sequence FV(X)7-20MXSLXYM(X)4MF. By expressing in Xenopus embryos a truncated E1a protein that contains only the second NLS and by monitoring its cytoplasmic/nuclear distribution during development with indirect immunofluorescence, we find that the second NLS is utilized up to the early neurula stage. In addition, there appears to be a hierarchy among the embryonic germ layers as to when the second NLS becomes nonfunctional. For this reason, we refer to this NLS as the developmentally regulated nuclear localization signal (drNLS). The implications of these findings for early development are discussed.


A statistical model based fundamental frequency synthesizer for Mandarin speech. A novel method based on a statistical model for the fundamental-frequency (F0) synthesis in Mandarin text-to-speech is proposed. Specifically, a statistical model is employed to determine the relationship between F0 contour patterns of syllables and linguistic features representing the context. Parameters of the model were empirically estimated from a large training set of sentential utterances. Phonologic rules are then automatically deduced through the training process and implicitly memorized in the model. In the synthesis process, contextual features are extracted from a given input text, and the best estimates of F0 contour patterns of syllable are then found by a Viterbi algorithm using the well-trained model. This method can be regarded as employing a stochastic grammar to reduce the number of candidates of F0 contour pattern at each decision point of synthesis. Although linguistic features on various levels of input text can be incorporated into the model, only some relevant contextual features extracted from neighboring syllables were used in this study. Performance of this method was examined by simulation using a database composed of nine repetitions of 112 declarative sentential utterances of the same text, all spoken by a single speaker. By closely examining the well-trained model, some evidence was found to show that the declination effect as well as several sandhi rules are implicitly contained in the model. Experimental results show that 77.56% of synthesized F0 contours coincide with the VQ-quantized counterpart of the original natural speech. Naturalness of the synthesized speech was confirmed by an informal listening test.


Effects of aging and dietary restriction on tissue protein synthesis: relationship to plasma insulin-like growth factor-1. Insulin-like growth factor-1 (IGF-1) decreases with age in many species and appears to have an important role in the age-related decline in capacity for protein synthesis with age. The goals of these studies were to determine whether (a) ad libitum fed mice demonstrate age-related decreases in IGF-1, (b) the relationship between IGF-1 and age-related changes in protein synthetic capacity in ad libitum fed animals, and (c) whether moderate dietary restriction (which increases both life span and protein synthetic capacity) delays age-related changes in protein synthesis and plasma IGF-1. These studies indicate that (a) in ad libitum fed animals, plasma IGF-1 decreases with age between 10 and 15 months and moderate dietary restriction decreases plasma IGF-1 in young but not older animals, and (b) the temporal changes in protein synthesis are tissue specific; moderate dietary restriction either increases or prevents the age-related decline in tissue protein synthesis. Results suggest that in normal aging, decreases in IGF-1 are associated with the decline in protein synthesis but that other regulatory mechanisms appear to have an important role in this process. Dietary restriction decreases plasma IGF-1 in young animals and either increases protein synthesis or prevents the age-related decline in protein synthesis, suggesting that the effects of dietary restriction are not mediated via increases in plasma IGF-1.


Estimating the prevalence of long-term disability for an aging society. Using information from two national data sets, this report provides projections of disability rates for the U.S. population age 65 and above. The research develops a series of projections based upon alternative sets of assumptions about mortality and disability. Using 1986 baseline disability data, estimates by single year of age are projected through the year 2040. The social policy implications of these projections are discussed in the final section.


Human dermal fibroblast interleukin-1 receptor antagonist (IL-1ra) and interleukin-1 beta (IL-1 beta) mRNA and protein are co-stimulated by phorbol ester: implication for a homeostatic mechanism. Although the major functions of fibroblasts are to produce extracellular matrix and to maintain a structural framework for organ systems, recent studies have demonstrated that fibroblasts are active participants in inflammatory processes by synthesizing various inflammatory mediators. In this report, we provide evidence that fibroblasts may contribute to the regulation of inflammation by the synthesis of both the intracellular form and the secretory form of interleukin-1 receptor antagonists in conjunction with interleukin-1 beta production. Indirect immunofluorescence microscopy localized interleukin-1 receptor antagonist and interleukin-1 beta proteins primarily in the fibroblast cytoplasm. Polymerase chain reaction amplification of reverse-transcribed mRNA with primers specific for the intracellular form of interleukin-1 receptor antagonist detected cDNA fragments present in both unstimulated and phorbol ester-stimulated fibroblasts, identical in molecular size to that in unstimulated keratinocytes. Amplification with primers specific for the secretory form of interleukin-1 receptor antagonist, however, detected cDNA fragments in phorbol ester-stimulated fibroblasts and phytohemagglutinin-stimulated peripheral mononuclear cells, but not in unstimulated fibroblasts or keratinocytes. The amplified fibroblast cDNA sequences for both intracellular and secretory interleukin-1 receptor antagonists were confirmed by digestion with three restriction endonucleases. By ethidium bromide visualization of amplified cDNA derived from serially diluted total cellular RNA and by Southern blot hybridization analysis of amplified cDNA, we have demonstrated that fibroblast interleukin-1 receptor antagonist mRNA and interleukin-1 beta mRNA were co-stimulated by phorbol ester. Similarly, ELISA demonstrated that fibroblast cytoplasmic interleukin-1 receptor antagonist protein and interleukin-1 beta protein were co-stimulated by phorbol ester. Our data suggests that the intracellular form of interleukin-1 receptor antagonist may be important in maintaining physiologic homeostasis in fibroblasts during interleukin-1 beta induction and release.


Inhibition of lecithin:cholesterol acyltransferase activity by synthetic phosphatidylcholine species containing eicosapentaenoic acid or docosahexaenoic acid in the sn-2 position. Phospholipids isolated from the plasma of monkeys fed a diet enriched in fish oil were poor substrates for cholesteryl ester (CE) synthesis by the lecithin:cholesterol acyltransferase (LCAT) reaction relative to those from animals fed a lard containing diet when the phospholipids were used for the preparation of recombinant particles by cholate dialysis (Parks, J. S., B. C. Bullock, and L. L. Rudel. 1989. J. Biol. Chem. 264: 2545-2551). The purpose of the present study was to directly test the influence of eicosapentaenoic acid (20:5 n-3) and docosahexaenoic acid (22:6 n-3) in the sn-2 position of phosphatidylcholine (PC) on the activity of LCAT. PC species containing 1-palmitoyl-2-oleoyl PC (POPC), 1-palmitoyl-2-linoleoyl PC (PLPC), 1-palmitoyl-2-arachidonoyl PC (PAPC), 1-palmitoyl-2-eicosapentaenoyl PC (PEPC), or 1-palmitoyl-2-docosahexaenoyl PC (PDPC) were purchased or synthesized and made into recombinant particles of uniform size and composition with [14C]cholesterol and apoA-I using the cholate dialysis procedure. The recombinant particles (PC:cholesterol:apoA-I molar ratio = 42:1.9:1) exhibited the following order of reactivity towards purified human LCAT in vitro: POPC greater than PLPC greater than PEPC = PAPC greater than PDPC. The apparent Vmax/Km for recombinant particles containing PEPC and PDPC was 17% and 7% that of particles containing POPC, respectively. There was a linear decrease in CE formation when the percentage of PEPC or PDPC was increased from 0 to 100% relative to POPC in recombinant particles with a constant PC:cholesterol:apoA-I molar ratio, suggesting that the PEPC and PDPC were competitive inhibitors of the LCAT reaction.(ABSTRACT TRUNCATED AT 250 WORDS)


Interleukin 1: an important mediator of host resistance against Pneumocystis carinii. The importance of endogenous interleukin 1 (IL-1) in resistance to Pneumocystis carinii infection was examined in a SCID mouse model. Naturally acquired pulmonary infection of P. carinii in SCID mice was completely cleared by reconstitution of the infected mice with immunocompetent spleen cells. IL-1 activity in the lung homogenate supernatant of these mice increased significantly after reconstitution and returned to baseline level after the clearance of P. carinii. Treatment of reconstituted SCID mice with 35F5, a monoclonal antibody against murine type I IL-1R almost completely inhibited the clearance of P. carinii. In contrast, treatment with control rat immunoglobulin G had no detectable effect. Further study revealed that for the complete clearance of P. carinii, IL-1 must be present at the early stage of immune responses induced by reconstitution, since clearance could be blocked by a single injection of 35F5 into SCID mice at 2 d, but not at either 8 or 13 d postreconstitution. Furthermore, pulmonary recruitment of neutrophils, macrophages, and lymphocytes was significantly inhibited in mice that received 35F5 treatment. These findings strongly suggest that, in reconstituted SCID mice, endogenous IL-1 is important in host resistance to P. carinii infection and that IL-1 may function early in the host response possibly by the recruitment of inflammatory cells into the lungs.


A 68-kD GTP-binding protein associated with the T cell receptor complex. The identity of the guanine nucleotide-binding protein (G protein) involved in T cell activation pathways remains unclear. We identified a 68-kD GTP-binding protein associated with the T cell receptor (TCR)/CD3 complex using immunoprecipitation and GTP-affinity labeling techniques. Proteins coimmunoprecipitated with the TCR/CD3 complex in digitonin lysate of a human leukemic T cell line, MOLT 16, were incubated with alpha-[32P]GTP and irradiated with ultraviolet rays to covalently link the labeled GTP to GTP-binding proteins. They were then analyzed by electrophoresis. The 68-kD protein exhibited nucleotide specificity for GTP-binding and was insensitive to cholera and pertussis toxins. The 68-kD GTP-binding protein could be coimmunoprecipitated with the TCR/CD3 complex but not with other surface molecules such as major histocompatibility complex class I and lymphocyte function associated-1, which do not cause rapid Ca2+ mobilization. These suggest that the 68-kD GTP-binding protein is specifically associated with the TCR/CD3 complex.


Huntington disease: a detective story.

Huntington disease: a detective story. As recombinant DNA diagnoses of various inherited diseases become a standard medical procedure, the practicing physician will be required to identify families at risk and counsel them (or refer them) appropriately. In many families the risk may not be immediately obvious or a reliable risk figure may appear to be unattainable. In the case presented, the patient had an apparent 50% risk for Huntington disease and all the immediate affected relatives were deceased. This relatively common scenario would generally prevent recombinant DNA diagnostic procedures from arriving at a more accurate risk estimate. Nevertheless, by recombinant DNA analysis, a risk for Huntington disease of less than 1% was obtained. Several key aspects of genetic analysis were required including extensive family histories, identification of informative markers, ordering the markers around the disease gene and appropriate statistical analyses. These discussions illustrate the power of recombinant DNA techniques to detect genetic disorders and demonstrate why they will be of increasing importance to the practicing physician.


Pharmacokinetics of potential anti-AIDS agents thiofoscarnet and foscarnet in the cat. The pharmacokinetics of thiophosphonoformate (TPFA) and phosphonoformate (foscarnet, PFA) were studied in normal adult cats, a species susceptible to feline immunodeficiency virus (FIV) infection. Parent drugs and metabolites were quantitated by high-performance liquid chromatography (HPLC). TPFA had a mean terminal plasma half-life of 42 min, a total clearance of 4.58 ml/min/kg, and a renal clearance of 1.24 ml/min/kg (N = 4). TPFA underwent in vivo metabolism to PFA and thiophosphonic acid (TPA); the latter was inactive against HIV reverse transcriptase. The 6-h cumulative urinary excretion was 42.3% of the intravenous administered dose of TPFA, consisting of 23.5% unchanged TPFA, 13.8% PFA, and 5.0% TPA. In comparison, PFA had a mean (N = 5) terminal half-life of 172 min and a total clearance of 1.88 ml/min/kg, approximating its renal clearance. There was no evidence of PFA metabolism. Oral doses of TPFA were administered either in enteric-coated capsules or in solution by gavage. The mean oral bioavailability of encapsulated TPFA and PFA was 22 and 8%, respectively. When given by gavage, TPFA had a higher mean bioavailability (33%), but with a greater variability. Based on the 6-h cumulative urinary excretion of TPFA, the mean oral bioavailability of TPFA was 44%, similar to that based on plasma data. The TPFA appears to be superior to PFA because of its greater oral bioavailability and its ability to deliver an active metabolite, PFA, to the systemic circulation after oral dosing.


Physical disability among Canadians reporting musculoskeletal diseases. About one million Canadian adults are estimated to have physical disabilities attributed to a musculoskeletal condition, a prevalence of 50.1/1,000 adults (all rates expressed/1,000). The specific musculoskeletal disease rates were arthritis/rheumatism (27.2), back (16.2), "other" (4.6), trauma (3.6) and bone (0.6). More women reported disabling musculoskeletal disease (61.0 versus 38.6, respectively). Prevalence rates increased with age from 6.2 among Canadians aged 15-24 years, to 264.7 aged 85 years and over. Limitations of mobility were more common than those of agility. Adults in institutions reported more disabilities than did adults in households (means 7.7 and 4.4, respectively).


Long-term followup with the use of lyophilized dura mater for abdominal wall closure in children: report of 3 cases. We report our experience with 3 children treated during infancy by abdominal wall reconstruction using lyophilized dura mater. Followup has been 36, 46 and 96 months postoperatively and they demonstrated adequate abdominal wall healing. One child has mild muscular diastasis, while 1 has completely healed. In 1 child a small defect developed in the repair, which was closed at a secondary procedure. Wound infection, dehiscence or herniation did not occur. There has been no evidence of Creutzfeldt-Jakob disease, which has been reported when allogenic dura was not obtained from registered tissue banks. Our experience with dura mater suggests that the material may be a useful adjunct in the repair and closure of complex abdominal defects.


Laparoscopic diverticulectomy: preliminary report of a new approach for the treatment of bladder diverticulum. Laparoscopic techniques have expanded the possibilities of endo-surgically approaching urological abnormalities that would otherwise be managed via an open operation. We report on another useful application of the laparoscope, bladder diverticulectomy. A large bladder diverticulum, responsible for incomplete bladder emptying and recurrent urinary tract infections in an 87-year-old man, was successfully excised endoscopically. The technique and possible future indications are described.


The problem of discrimination in health care priority setting. Increasingly stringent fiscal restrictions on the scope of medical services available to patients have resulted in calls for explicit health care priority setting. Several commentators have called for the application of decision-analytic principles to such efforts, which would assign services priority based on the extent to which they produce preferred health outcomes. The Oregon Medicaid exercise is an example of such a process. An important challenge to these utilitarian efforts is the need to avoid discrimination against people with medical disabilities. Both of the key elements entailed by decision-analytic approaches to priority setting--estimation of outcomes and assignment of values to those outcomes--are vulnerable to charges of discrimination, primarily because both the medical outcomes expected in disabled individuals and the values they place on those outcomes may differ from the general public. Priority-setting efforts must proceed carefully to avoid the appearance (and reality) of discrimination.


[Study of yearly changes in intractable disease patients receiving financial aid for treatment]. Yearly changes of intractable disease patients receiving financial aid for treatment were observed for 24 intractable disease patients from 1983 to 1987. The results obtained were as follows. 1. The number of intractable disease patients receiving financial aid for treatment increased from 1983 to 1987 for 23 of the diseases. Only the number of SMON patients did not increase. 2. Medical care expenditures for these patients also increased since 1983. Greater increases for in-patients than for out-patients were seen for Huntington's chorea and Behcet's disease, while larger increases were seen for out-patients with Parkinson's disease, Scleroderma.dermatomyositis.primary multiple myositis, Buerger's disease, and others. 3. The proportion of national health insurance holders among intractable disease patients was 42.1% as compared with 34.7% among total national patients. The proportion was especially higher for Huntington's chorea (64.6%), Parkinson's disease (64.1%) and SMON (59.4%) patients.


Relationships among natriuresis, atrial natriuretic peptide and insulin in insulin-dependent diabetes. Insulin-dependent diabetic patients have a large exchangeable body sodium pool, secondary to sodium retention. The pathogenesis of impaired natriuresis in insulin dependent diabetes remains to be elucidated. The present study examines the role of hyperinsulinemia, impaired atrial natriuretic release, and resistance to atrial natriuretic peptide action in determining sodium retention in normotensive and hypertensive insulin-dependent diabetic patients. Eight insulin-dependent diabetic patients had significantly higher daily sodium excretion rate (147 +/- 16 mmol/day; mean +/- SE) during conventional insulin treatment (daily plasma glucose: 11.6 +/- 1.2 mmol/liter; daily plasma insulin: 27 +/- 3 microU/ml) than during intensified insulin treatment (daily sodium excretion rate: 91 +/- 12, P less than 0.01; daily plasma glucose: 6.8 +/- 0.7, P less than 0.01; daily plasma insulin: 44 +/- 4, P less than 0.01). Daily sodium excretion rate was also significantly lower (107 +/- 13, P less than 0.01) in the same diabetic patients during intensified insulin treatment along with hyperglycemic clamp (daily plasma glucose: 12.8 +/- 0.3, NS; plasma insulin 48 +/- 4, P less than 0.01). Seven control subjects had lower extracellular liquid volume than eight insulin-dependent diabetic patients (11.0 +/- 0.8 l/1.73 m2 vs. 14.8 +/- 0.9, P less than 0.05) and also had baseline plasma atrial natriuretic peptide concentrations (18 +/- 5 pg/ml vs. 37 +/- 4, P less than 0.05). Atrial natriuretic peptide response to saline challenge was blunted in insulin-dependent diabetic patients when saline was administered on the basis of body surface area (90 mmol/1.73 m2.90 min) but not when administered on the basis of extracellular liquid volume (ECV) (8.2 mmol/liter ECV.90 min).(ABSTRACT TRUNCATED AT 250 WORDS)


Nifedipine versus fosinopril in uninephrectomized diabetic rats. Antihypertensive agents have been shown to exert inequivalent effects on glomerular injury in experimental renal disease models. To compare the consequences of dissimilar antihypertensive regimens on the development of diabetic glomerulopathy, studies were performed in three groups of uninephrectomized moderately hyperglycemic diabetic rats. One group (DM) received no therapy except insulin. The remaining groups received insulin and either the angiotensin I converting enzyme inhibitor, fosinopril (FOS), or the calcium channel blocker, nifedipine (NIF). Both drugs lowered blood pressure comparably. At four to eight weeks, DM rats exhibited elevation of the single nephron glomerular filtration rate (SNGFR), due to elevations of the glomerular capillary plasma flow rate (QA) and the glomerular capillary hydraulic pressure (PGC). Neither NIF nor FOS affected values for SNGFR or QA. However, while FOS lowered PGC and increased Kf, NIF did not affect these parameters. In longer term (8 month) studies, DM rats exhibited progressive albuminuria and glomerular sclerosis. FOS markedly limited development of albuminuria and glomerular injury, but NIF was ineffective in limiting either parameter of glomerular injury. Thus, in contrast to the beneficial effects of converting enzyme inhibitors, chronic calcium channel blockade with nifedipine fails to limit PGC or glomerular injury in diabetic rats. These findings lend further support to the concept that different classes of antihypertensive agents are not equally effective in protecting against diabetic glomerulopathy.


Urinary C3dg and C5b-9 indicate active immune disease in human membranous nephropathy. We have measured complement activation markers, C3dg and C5b-9 in plasma and urine from patients with idiopathic membranous nephropathy and IgA nephropathy. There was no significant difference in levels of plasma C5b-9 between the patient groups. However, high plasma concentrations of C3dg were associated significantly with IgA nephropathy with 45% of patients having levels over 25 U/ml (P less than 0.001). High concentrations of urinary C3dg and C5b-9 were associated significantly with membranous nephropathy (43% and 43% of the patient group, respectively) compared to patients with IgA nephropathy (10% and 0%, respectively, P less than 0.001). In a retrospective analysis of 31 patients with membranous nephropathy, 66% of patients with high initial urinary C5b-9 showed an unstable clinical course compared to 18% of patients with initially absent or low C5b-9 (P less than 0.001). We suggest that high urinary C5b-9 identifies those patients with a membranous lesion which retains an active immunological component contributing to the pathology of progressive glomerular damage.


Thromboxane receptor blockade reduces renal injury in murine lupus nephritis. To investigate the role of thromboxane A2 (TxA2) in murine lupus, we assessed the effects of the specific thromboxane receptor antagonist GR32191 on immune complex glomerulonephritis in MRL-lpr/lpr mice. Forty mg/kg/day GR32191 was given by twice daily subcutaneous injection for eight weeks beginning at 12 weeks of age. This dose completely blocked the renal vasoconstriction produced by the thromboxane agonist U46619. After eight weeks of treatment, both glomerular filtration rate (GFR) (8.9 +/- 0.6 vs. 6.8 +/- 1.1 ml/min/kg; P less than 0.05) and PAH clearance (CPAH) (37.4 +/- 2.5 vs. 29.9 +/- 3.3 ml/min/kg; P less than 0.05) were significantly higher in mice given GR32191 compared to vehicle treated animals. Administration of GR32191 also reduced proteinuria from 18.1 +/- 11.6 to 3.7 +/- 1.3 mg/24 hours (P less than 0.05). In GR32191 treated MRL-lpr/lpr mice, renal hemodynamic function and proteinuria were not significantly different from congenic MRL-+/+ controls. Thromboxane receptor blockade had striking affects on renal histomorphology reducing both hyaline thrombi in glomeruli (P = 0.022) and interstitial inflammation (P = 0.006). Glomerular crescents and severity of vasculitis also tended to be reduced in mice receiving the thromboxane receptor antagonist. The overall histopathologic score in mice given GR32191 was significantly lower than vehicle treated animals (4.7 +/- 0.5 vs. 8.4 +/- 1.5; P = 0.016). These effects of GR32191 were associated with decreased excretion of thromboxane B2 (TxB2) in urine (292 +/- 37 vs. 747 +/- 155 pg/24 hr; P less than 0.005) as well as a modest reduction in glomerular deposits of IgG (semiquantitative score 2.6 +/- 0.2 vs. 3.5 +/- 0.2; P less than 0.02). Thus, chronic thromboxane receptor blockade markedly altered the course of renal disease in MRL-lpr/lpr mice, suggesting that TxA2 is an important mediator of renal dysfunction and injury in this murine model of lupus nephritis.


Reduced glomerular thromboxane receptor sites and vasoconstrictor responses in diabetic rats. Glomerular thromboxane production and urinary thromboxane excretion are increased in early diabetes, but in spite of this renal blood flow and glomerular filtration rate are significantly higher than in control animals. To study the possibility of a defect in thromboxane actions in the kidney, we have measured glomerular thromboxane receptors and the renal hemodynamic response to the administration of a stable thromboxane analog in diabetic rats. Glomerular thromboxane receptors were studied in hyperglycemic diabetic rats 7 to 10 days after injection of streptozotocin (65 mg/kg, i.v.) and in normal controls. Scatchard analysis of equilibrium binding using the thromboxane antagonist, [3H]-SQ29548, demonstrated one class of high affinity thromboxane receptor sites in control (Kd = 19.9 +/- 2.6 nM, N = 16) and diabetic rats (Kd = 19.8 +/- 2.1 nM, N = 8, P = NS). The number of thromboxane receptors was reduced by 44% in diabetic rats (control, 374 +/- 20 vs. diabetic, 210 +/- 21 fmol/mg, P less than 0.01). Thromboxane binding in diabetic rats was not restored to normal levels by thromboxane synthetase inhibition with OKY046. Diabetic rats had higher renal blood flow (diabetic, 7.03 +/- 0.18 vs. control, 6.33 +/- 0.13 ml/min, P less than 0.05) and glomerular filtration rate (2.42 +/- 0.10 vs. 1.96 +/- 0.07 ml/min, P less than 0.05). Infusion of the stable thromboxane agonist, U46619 (0.1 micrograms/kg/min), reduced renal blood flow and glomerular filtration rate in all animals, but the constrictor responses were blunted by 50% in hyperglycemic diabetic rats compared with normal controls or euglycemic diabetic rats (P less than 0.05). Control of blood glucose with insulin normalized the number of glomerular thromboxane receptor sites, reversed hyperfiltration and restored glomerular responses to thromboxane agonist. The abnormalities of glomerular thromboxane receptors are similar to changes in angiotensin II receptors, and suggest a generalized defect in vasoconstrictor receptors in the diabetic kidney.


Antibiotic prophylaxis for cardiothoracic operations. Meta-analysis of thirty years of clinical trials. Antistaphylococcal penicillins and first-generation cephalosporins have traditionally been the prophylactic antibiotics of choice for patients undergoing cardiothoracic operations. Recently published studies have claimed improved outcomes with respect to postoperative wound infection when second-generation cephalosporins were used for prophylaxis. The purpose of this study was to critically review the infectious outcomes of prospective, randomized, and controlled studies of cardiothoracic surgery prophylaxis by means of meta-analytic techniques. For each of 28 studies meeting the meta-analysis entry criteria, odds ratios with 95% confidence intervals were calculated to compare the prophylactic efficacy of the antibiotic regimens. Odds ratios were then pooled, and a summary odds ratio was calculated for each pairing of antibiotic treatments. Placebo-controlled trials of cardiothoracic prophylaxis demonstrated a consistent benefit to the administration of antibiotic prophylaxis, with an approximate fivefold reduction in wound infection rate. The second-generation cephalosporins, cefamandole and cefuroxime, performed better than cefazolin, with an approximate one and one-half-fold reduction in wound infection rate. Administration of prophylaxis beyond 48 hours was not associated with improved infectious outcomes.


Postoperative erythroderma after cardiac operations. The possible role of depressed cell-mediated immunity. Erythroderma as a manifestation of graft-versus-host disease after cardiac operations with blood transfusion may occur more frequently in Japan than in other countries. We have seen this problem in five patients who, after heart operations, died with symptoms and signs characteristic of graft-versus-host disease: cutaneous eruption, fever, diarrhea, leukopenia associated with agranulocytosis, and liver dysfunction. In the three patients seen most recently, skin biopsy showed findings similar to those of graft-versus-host disease after bone marrow transplantation. In addition, immunologic investigation showed remarkable differences in the findings in these patients and in those who did not have a graft-versus-host disease-like syndrome after cardiac operations. In particular, interleukin-2 production in response to mitogen stimulation was markedly diminished after operation in our patients, and the ratio of OKT4+ cells to OKT8+ cells in peripheral blood was low, reflecting increased numbers of OKT8+ cells after the occurrence of symptoms. The results raise the possibility that transient depression of cellular immunity after cardiac operations with blood transfusion may contribute to the occurrence of postoperative acute graft-versus-host disease.


Fibrin sealant for early repair of acquired ventricular septal defect. The trend toward early operation for acquired ventricular septal defects exposes the patient to major perioperative bleeding and residual shunt because of the fragility of the recently necrosed myocardium. To reduce these complications we have used a fibrin sealant to reinforce the cardiac tissues in addition to the usual closure of the defect with a Dacron patch through a left ventricular septum around the defect, area. During cardiac arrest fibrin sealant is applied on the ventricular septum around the defect, between the septum and the patch, and on the edges of the ventriculotomy. This technique was used in three patients (mean age 68.2 years) operated on for an acquired ventricular septal defect within 4 days of the infarction and within 24 hours of the occurrence of the defect. Low postoperative bleeding, absence of recurrent shunt, and good ventricular function indicated satisfactory surgical result in all three patients. We suggest that the use of fibrin sealant during operations for acquired ventricular septal defects, by reinforcing the necrotic and fragile tissues, may reduce perioperative bleeding and assure a more solid implantation of the patch.


Single lung transplantation in rats with fatal pulmonary hypertension. Effects of single lung transplantation on fatal pulmonary hypertension were evaluated in rats receiving a lethal dose of monocrotaline. Inbred rats treated with monocrotaline (80 mg/kg) received a left lung isograft at 4 weeks (n = 9) and at 6 weeks (n = 6), when moderate and severe pulmonary hypertension, respectively, had developed. Medicated (n = 12) and nonmedicated rats (n = 12) served as control animals. Each rat was tested weekly with treadmill for exercise tolerance and oxygen consumption during a 10-week period after medication and after they were killed. Medicated control rats lost exercise tolerance and highest oxygen consumption per unit time consistently to the range of resting value (or 45% of nonmedicated control rats), and all died from severe pulmonary vascular occlusive disease with right ventricular hypertrophy before 10 weeks (right ventricular/left ventricular weight ratio of 1.16). All rats receiving a left lung isograft at 4 weeks survived and regained highest oxygen consumption per unit time (87% of nonmedicated control rats), with the lung transplant receiving 65% (nonmedicated control rats, 39%) of cardiac output and milder right ventricular hypertrophy (right ventricular/left ventricular weight ratio of 0.46). Except for one, all rats that received a left lung isograft at 6 weeks tolerated single lung transplantation, but they died soon after reperfusion because of pulmonary edema in the graft that received 58% of cardiac output with right ventricular/left ventricular weight ratio of 0.79. Results of single lung transplantation in rats were dependent on severity of pulmonary hypertension. In rats with moderate pulmonary hypertension, single lung transplantation was successful in reversing exercise intolerance and right ventricular hypertrophy. Single lung transplantation was unsuccessful when pulmonary hypertension was severe in the rat model because increased flow toward the lung transplant resulted in graft pulmonary edema.


Efficacy of danazol treatment in infertile patients with endometriosis. The study was done to assess the efficacy of danazol in the treatment of infertile patients with all stages of endometriosis. The cumulative pregnancy rates in 21 patients with Stage I and II endometriosis were compared to 21 patients with Stage III and IV endometriosis. Both groups had danazol treatment for six months. All other fertility related factors were controlled for in both groups. There was a cumulative pregnancy rate of 11% (standard error 7%) at 12 months of follow-up in the group with Stage I and II disease whilst it was 26% (standard error 10%) in the group with moderate or severe disease. These results question the validity of any classification system in prognosticating for fertility in patients with endometriosis.


Legionella species isolated from cooling towers in Kuala Lumpur. Three building complexes in Kuala Lumpur were surveyed for the presence of legionellae in cooling towers. The organisms were grown from 12 out of 46 samples of water collected from 30 towers. L. pneumophila serogroups 1 and 7 were the commonest serogroups isolated. None belonged to the Pontiac subgroup of L. pneumophila serogroup 1.


Incidence of postdural puncture headache. A prospective study of 101 spinal anaesthetics in orthopaedic patients. Spinal anaesthesia was performed on 101 patients with a 25-Gauge (0.52 mm) needle. We found a 13.9% overall incidence of postdural puncture headache (PDPH) in an orthopaedic population whose mean age was 33.6 years. This incidence is too high and an alternative technique may be needed.


A comparison of sodium citrate and sodium citrate/ranitidine combination for acid aspiration prophylaxis. The effectiveness of sodium citrate and sodium citrate/ranitidine were compared in two randomised groups of elective caesarean patients during the various phases of anaesthesia. The mean pH values (3.5, 3.3, 3.6) were lower in the citrate group compared to the citrate/ranitidine group (6.1, 6.3, 5.9). The percentage of patients with pH values less than 2.5 was 40% in the citrate group compared to 7% in the citrate/ranitidine group. Sodium citrate alone is less effective than sodium citrate/ranitidine for acid aspiration prophylaxis.


Anaesthesia for closed embolisation of cerebral arteriovenous malformations. Anaesthetic experience of the first nine patients in Singapore who underwent closed embolisation of cerebral arteriovenous malformations is reported. Six patients had neurolept analgesia and three had general anaesthesia.


Post-menopausal smear patterns--a review of vaginal smears in 480 women. Cytohormonal evaluation was done on the vaginal smears of 480 normal, asymptomatic, post-menopausal women whose ages ranged from 36 to 74 years. About 50% showed atrophic smears consistent with total oestrogen lack. 41% had mild to moderately proliferative smears compatible with sub-optimal oestrogen stimulus. 9% showed a highly proliferative pattern typical of unopposed oestrogen effect and in this group two women had atypical endometrial cells in their smears, which subsequently were found to come from an atypical endometrial hyperplasia and an endometrial adenocarcinoma-in-situ. The clinical relevance of cytohormonal studies in post-menopausal women is briefly discussed.


A microbiological study of vaginal discharge in women attending a Malaysian gynaecological clinic. Vaginal discharge is a common complaint of women attending gynaecological clinics. The purpose of this study was to compare the occurrence of commonly implicated microorganisms in vaginal discharge amongst women with or without the complaint, attending a gynaecological and family planning clinic. The association of Gardnerella vaginalis with bacterial vaginosis was also studied. It was found that there were no significant differences between the cases and controls in the isolation rate of Gardnerella vaginalis, Torulopsis glabrata, Ureaplasma urealyticum, Mycoplasma ssp and Group B streptococcus (p greater than 0.05). Only the isolation rate of Candida albicans was significantly higher in the cases than controls (p less than 0.01). However, there was a significant association of G. vaginalis with bacterial vaginosis.


Incidence and management of middle ear effusion in cleft palate patients. For a complete overall rehabilitation of cleft palate patients a multi-disciplinary approach should be adopted. Plastic and Head and Neck Surgeons in whom most of the treatment are entrusted should be concerned not only at achieving palatal function and cosmetic acceptability but also the various other problems associated with cleft palate especially hearing loss. In this study, 66 patients with repaired and unrepaired cleft palates were examined for the presence of hearing loss due to middle ear effusion. The incidence of middle ear effusion was high (57.6%). It was also found that only eight of these patients (12.1%) ever complained of hearing loss or any associated symptoms and repair of the cleft palate did not influence the incidence of middle ear effusion. As such, screening should be done in all cleft palates and otolaryngologists should therefore play an important role in the multi-disciplinary team which should comprise the paediatrician, plastic surgeon, speech therapist, orthodontist and dental specialist.


Morbidity and mortality of infants of diabetic mothers born at the Maternity Hospital, Kuala Lumpur. A prospective study was carried out in the Maternity Hospital, Kuala Lumpur in 1989 to determine the morbidity and mortality of infants of diabetic mothers. Out of 24,856 neonates born during the study period, 54 neonates (2.2 per 1000 livebirths) were born to mothers who were diagnosed to have diabetes mellitus before the current pregnancy or who had impaired glucose tolerance test during the current pregnancy. Almost a third (29.6 percent) of these infants of diabetic mothers had birthweight of 4000 grams and above, and 37.0 percent of the 54 babies were large-for-gestational age. Hypoglycemia occurred in 9/54 (16.7 percent) of the neonates, respiratory distress syndrome in 5/54 (9.3 percent), shoulder dystocia in 7/54 (13.0 percent), and congenital abnormalities in 4/54 (7.4 percent). Three (5.6 percent) neonates died during the neonatal period. The results of this study suggest a need to intensify control of maternal diabetes mellitus during pregnancy in order to reduce the rates of morbidity and mortality of their infants.


A retrospective review of tracheal suction at birth in neonates with meconium aspiration syndrome. A retrospective study of 54 neonates with Meconium Aspiration Syndrome (MAS) admitted to the Paediatric ICU Penang General Hospital from January 1989-December 1990 was carried out to determine if suction of the trachea at birth was performed in this group of patients. 63% were inborn and 27% outborn. The mean birth weight was 3.2 kg, 83% were ventilated, mean duration of ventilation was five days and the mortality was 24%. 63% had an Apgar Score of less than 5 at 1 min and 65% had thick meconium-stained liquor. Only 48% were intubated and suctioned at birth. Overall tracheal suction rate was low.


Modified subtotal cholecystectomy: a procedure for the difficult gall bladder. Modified subtotal cholecystectomy involves removal of the gall bladder after circumferential division of the neck. Either the impacted stone or the surgeons finger was used as a guide to identify the neck. The stump cavity in the neck is obliterated with interrupted sutures to prevent recurrent stone formation. Indications for this procedure are obscure anatomy, due either to the severe inflammation in acute cholecystitis or dense adhesions in the small fibrosed gall bladder. The decision to perform modified subtotal cholecystectomy is taken during the operation. Forty three patients (14%) underwent this procedure during the period between August 85 and April 90. Out of 289 cholecystectomies performed seven were emergency and thirty-six were early cholecystectomies. With the increasing trend towards urgent and early cholecystectomy in acute cholecystitis the author has found this to be a safe and definitive procedure.


Allergic skin tests in Malaysian asthmatics. To assess the prevalence of skin test sensitivity among asthmatic patients in Malaysia, skin prick tests for allergy in 134 adult asthmatic patients and 120 control subjects were done. 90% of asthmatic patients had positive skin test to at least one allergens as compared to 78% of the controls. House dust mite was the most frequent allergen to which the subjects had positive reactions. Sixty-four percent of the asthmatic patients had associated rhinitis. There was no significant difference in the skin test sensitivity between asthmatic patients with associated rhinitis and those without.


Total occlusion of left main coronary artery in a patient with chronic, stable angina. We report a case of total occlusion of the left main coronary artery (LMCA) in a patient with chronic, stable angina. Total occlusion of the LMCA is rare and survival depends on the existence of collateral circulation. In LMCA disease, there is usually also disease in other parts of the coronary arterial tree.


Early experiences of intra-operative trans-oesophageal echocardiography (TEE) in mitral valve repair. Whenever possible Mitral valve repair should be performed instead of Mitral valve replacement. It is important to assess the adequacy of the repair during the operation so that any corrective steps may be taken immediately. We present three cases of Mitral valve repair in which the intraoperative TEE was used to assess the adequacy of the repair. There was good correlation of the immediate post bypass TEE findings and early post operative transthoracic echocardiographic findings. Intraoperative TEE is a useful tool in the early assessment of Mitral Valve Repair.


[Evaluation of nutritional status in patients with esophageal cancer by measurement of sternocleidomastoid, rectus abdominis and quadriceps muscles on ultrasound imaging]. To assess the nutritional status of the patients with esophageal cancer, we measured the areas of sternocleidomastoid and rectus abdominis muscles (SMA, RAMA) on real time ultrasound imaging and calculated muscle index (MI = (SMA+RAMA/Height)). Eighty-three patients with esophageal cancer were included in the present study. Preoperatively, significant Spearman's coefficients were found between MI and the percentage of standard arm circumference (R = 0.52) and between MI and the percentage of standard arm muscle circumference (R = 0.51). Postoperatively, patients with wide muscle area showed high values of prealbumin, transferrin and fibronectin. To study the changes after surgery, we also measured the area of quadriceps muscle in patients with esophageal cancer. The areas of quadriceps muscle in patients with dysphagia were much diminished than in those without dysphagia. Measurement of areas of muscles such as SMA, RAMA and quadriceps muscle was proved to be a useful procedure in evaluating the nutritional status of patients with esophageal cancer.


[Assessment for protective effects of CoQ10, PGE1 and TXA2 receptor antagonist (ONO-3708) on warm ischemic liver]. Metabolic disturbances in the canine liver during warm ischemia by Pringle's method for 60 minutes and the role of Coenzyme Q10 (CoQ10), Prostaglandin E1 (PGE1) and ONO-3708, TXA2 receptor antagonist, were studied. Mongrel dogs were divided into five groups; control group, group of liver ischemia without drugs, groups of liver ischemia with CoQ10, PGE1 and ONO-3708 pretreatment. Metabolic rates of PGI2, TXA2, insulin, glucagon and glucose and production of lipid peroxides in the five groups were measured at the points before Pringle's procedure, 5 minutes, 60 minutes and 120 minutes after declamping. In the group of ischemia without drug administration, the hepatic metabolism of PGI2, TXA2, insulin and glucose were decreased after declamping. The metabolism of glucagon, however, was not disturbed by warm ischemia. The production of lipid peroxides increased at 5 minutes after declamping. In the groups of CoQ10, PGE1 and ONO-3708 pretreatment, changes of PGI2, TXA2 and insulin metabolism in the liver were improved, and an increased production of lipid peroxides by warm ischemia was normalized. This study suggests that CoQ10, PGE1 and ONO-3708 protect liver damage by warm ischemia as results of improvement of metabolic disturbances of PGI2, TXA2, insulin and suppression of lipid peroxides production.


Characterization of fumonisin toxicity in orally and intravenously dosed swine. Fumonisin B1 (FB1), a recently identified mycotoxin produced by Fusarium moniliforme in corn, has been shown to cause death in swine due to pulmonary edema, an apparently species specific effect, and to interfere with sphingolipid metabolism in vitro. Here we characterize the toxicity of fumonisins, using female cross-bred swine weighing 6 to 13 kg, and present a hypothesis regarding the mechanism of fumonisin-induced pulmonary edema in swine. FB1 was given daily intravenously (IV) to pig 1 for 9 days for a total of 72 mg (7.9 mg/kg) and to pig 2 for 4 days for a total of 67 mg (4.6 mg/kg). Pig 3 (control) was given saline IV for 9 days. Corn screenings naturally contaminated with FB1 (166 ppm) and FB2 (48 ppm) were fed to pigs 4, 5, and 6, and ground corn was fed to pigs 7 and 8 (controls). Pigs 4 and 7 were killed on day 5; pig 5 was found dead on day 6; and pigs 6 and 8 were killed on day 15. Pigs 4 and 5 had ingested 187 and 176 mg total fumonisins, respectively, while pig 6 had ingested 645 mg. Feed consumption had decreased in pigs fed corn screenings, with an additional sharp decrease prior to onset of clinical signs. Increases in serum liver enzymes, total bilirubin, and cholesterol were present, but electrocardiograms, heart rate, and body temperature were unaffected. Pigs dosed IV with FB1, developed mild intermittent respiratory abnormalities, while those fed screenings developed respiratory distress within 5 days. Mild interstitial pulmonary edema was observed in pig 1. Severe interstitial pulmonary edema, pleural effusion, and increased lung wet/dry weight ratio were observed in pigs 4 and 5. All pigs given fumonisin (either IV or orally) had hepatic changes characterized by hepatocyte disorganization and necrosis; pancreatic acinar cell degeneration was also observed. Ultrastructural changes in orally dosed swine included loss of sinusoidal hepatocyte microvilli; membranous material in hepatic sinusoids; and multilamellar bodies in hepatocytes, Kupffer cells, pancreatic acinar cells and pulmonary macrophages. Pulmonary intravascular macrophages (PIMs) contained large amounts of membranous material. Thus, the target organs of fumonisin in the pig are the lung, liver, and pancreas. At lower doses, slowly progressive hepatic disease is the most prominent feature, while at higher doses, acute pulmonary edema is superimposed on hepatic injury and may cause death. We hypothesize that altered sphingolipid metabolism causes hepatocellular damage resulting in release of membranous material into the circulation.(ABSTRACT TRUNCATED AT 400 WORDS)


Regional distribution of monoamines and dopamine D1- and D2-receptors in the striatum of the rat. Dopamine (DA) D1- and D2-receptor densities were determined in 18 discrete areas of the caudate-putamen-globus pallidus of male Wistar rats and compared to local DA concentrations. All three parameters were found to decrease caudally. The globus pallidus was distinguished by the low concentration of DA and its receptors and high noradrenaline (NA) content. While there were no mediolateral differences in DA or DA D1-receptors, a clear mediolateral gradient was observed for DA D2-receptors which extended over several sections of the brain. The ratio of DA D1- to D2-receptors was significantly higher in the dorsal than in the ventral areas of the mediolateral and caudal striatum. This is the first report of clear dorsoventral differences in parameters relating to DA activity in the striatum. These findings may be of particular significance in understanding the functional dichotomy between the dorsal and ventral striatum.


Paralimbic frontal lobe hypometabolism in depression associated with Huntington's disease. We measured regional cerebral glucose metabolism using 2-[18F]-fluoro-2-deoxy-D-glucose and positron emission tomography in depressed and nondepressed patients with early Huntington's disease (HD), compared with appropriately matched controls. Caudate, putamen, and cingulate metabolism was significantly lower in patients with HD than in control subjects, independent of mood state. Orbital frontal-inferior prefrontal cortex hypometabolism, however, differentiated depressed patients from both nondepressed patients and normal controls. These findings implicate selective dysfunction of the paralimbic regions of the frontal lobes in the mood disorder of HD. The metabolic pattern is similar to that in depression associated with Parkinson's disease, suggesting that the integrity of pathways linking paralimbic frontal cortex and the basal ganglia may be integral to the normal regulation of mood.


Serotonergic dysfunction in depression associated with Parkinson's disease. A 55-year-old man presented with a 5-year history of Parkinson's disease and a 6-month history of major depression. The patient's depressive symptoms responded to treatment with fluvoxamine, a selective and potent serotonin reuptake inhibitor. Tryptophan depletion testing, which acutely lowers central serotonin levels, caused a brief exacerbation of the depressive illness, which resolved upon tryptophan repletion. Serotonergic dysfunction may be an etiologic factor in depression that occurs in Parkinson's disease.


Outcome of preoperative against-the-rule astigmatism after phacoemulsification: characteristic changes over time. Part II. To determine the outcome of preoperative against-the rule (AR) astigmatism among 1,648 phacoemulsification and aspiration (PEA) procedures, we analyzed the post-cataract time course of astigmatism over 6 months in 618 eyes divided into three groups. In preoperative AR astigmatism less than 0.75 dptr (n = 208), the astigmatism increase 1 week postoperatively was rapid. In preoperative AR astigmatism greater than or equal to 1.5 dptr (n = 185), no difference in the power of astigmatism was apparent between 1 and 3 months postoperatively. The third group (0.75 less than or equal to preoperative AR astigmatism less than 1.5 dptr, n = 143) showed intermediate characteristics. The eyes with preoperative low AR astigmatism showed exacerbation of astigmatism after the PEA procedure, whereas the degree of astigmatism, corneal curvatures and the rate of AR astigmatism became lower in the eyes with higher preoperative AR astigmatism.


NMDA receptor antagonist MK-801 blocks non-opioid stress-induced analgesia in the formalin test. The analgesic effect of a 3-min swim stress was assessed using the formalin test. Male Swiss mice were injected i.p. with naloxone (0.1 or 1.0 mg/kg), MK-801 (0.075 mg/kg) or saline 15 min prior to swimming in water maintained at 20 degrees C or 32 degrees C. The mice were then injected with 20 microliters of 5% formalin into the plantar surface of 1 hind paw and pain behaviour (time spent licking the injected paw) was continuously monitored during the subsequent 10 min. Swim stress produced a significant reduction in pain behaviour at both 20 degrees C and 32 degrees C. MK-801 completely blocked the analgesia produced by both the 20 degrees C and 32 degrees C swim. At a dose of 0.1 mg/kg, naloxone partially antagonized the analgesia produced by the 32 degrees C swim but did not affect the analgesia produced by the 20 degrees C swim. Naloxone at a dose of 1.0 mg/kg had no effect on swim stress-induced analgesia. Neither MK-801 nor 0.1 mg/kg naloxone altered baseline pain behaviour, although 1.0 mg/kg naloxone did significantly reduce it. It is unlikely that the effect of MK-801 on swim stress-induced analgesia is due to an interaction with an opioid mechanism, as MK-801 had no effect on morphine analgesia. These results suggest that the analgesia produced by the 20 degrees C swim stress in the formalin test is non-opioid in nature and mediated via the NMDA receptor, whereas the 32 degrees C swim stress-induced analgesia has both an opioid and non-opioid component.


The treatment of depression in chronic low back pain: review and recommendations. The prevalence of major depression in patients with chronic low back pain (CLBP) is approximately three to four times greater than that reported in the general population. In spite of these high prevalence rates, there have been few systematic attempts to investigate the efficacy of treatment for major depression in patients with CLBP. While several studies have examined the efficacy of antidepressant medication and psychological treatment in patients with chronic pain, most of these studies have focused on treating chronic pain rather than depression. The few studies that have specifically addressed the treatment of depression in CLBP indicate that tricyclic antidepressants and cognitive-behavioral approaches may be effective means of treating depressed chronic pain patients. Clinical issues related to diagnostic confounds, rehabilitation outcome, and conceptualizations of the relation between pain and depression are discussed. It is argued that, in patients with clinical levels of depression, treatment modalities specifically targeting depressive symptomatology deserve serious consideration as an integral component of pain management programs.


[Hereditary glucose-6-phosphate dehydrogenase deficiency in newborn infants]. Early diagnosis of the deficiency of glucose 6-phosphate dehydrogenase was made in examining 428 samples of funic blood from 230 boys and 198 girls. The normal level of the enzyme activity was established in red blood cells of the healthy newborn with regard to the national and sexual differences. The hereditary character of the deficiency of glucose 6-phosphate dehydrogenase was supported in 37 neonates by analyzing the pedigrees. The enzyme deficiency was associated with different forms of hemoglobinopathies: alpha- and beta-thalassemia, structurally abnormal hemoglobin S and methemoglobinemia. The considerable prevalence of the deficiency of glucose 6-phosphate dehydrogenase was revealed in Azerbaijan for the first time. The phenotypic frequency amounted to 8.64% whereas the gene one to 0.0623.


First-trimester maternal serum human chorionic gonadotrophin as a marker for fetal chromosomal disorders. The Dutch Working Party on Prenatal Diagnosis. The Dutch Working Party on Prenatal Diagnosis has initiated a study on the possibilities of first-trimester screening for fetal chromosomal disorders. We report on maternal serum human chorionic gonadotrophin (MS-hCG) measurements in 1348 pregnancies with a chromosomally normal fetus and 53 pregnancies with a chromosomally abnormal fetus. The median MS-hCG concentration in 24 pregnancies with Down's syndrome was 1.19 multiples of the normal median (MoM). The MS-hCG distributions in normal and Down's syndrome pregnancies did not differ significantly (t-test: t = 1.945, p greater than 0.05). We also found no difference between normal pregnancies and pregnancies with other chromosomal disorders (six cases of trisomy 18, MoM = 0.80; four cases of sex chromosome abnormality, MoM = 1.01; 17 cases of chromosomal mosaicism in chorionic villi, MoM = 1.11). Selecting an upper limit at the 90th centile could detect 25 per cent of pregnancies with Down's syndrome. We conclude that, in the first trimester, MS-hCG as a screening factor for Down's syndrome is of minor value. However, MS-hCG could be a useful factor in a first-trimester screening programme based on a combination of markers.


Variation in the levels of pregnancy-specific beta-1-glycoprotein in maternal serum from chromosomally abnormal pregnancies. Human pregnancy-specific beta-1-glycoprotein (SP1) was assayed retrospectively in stored maternal serum (MS) samples from 82 chromosomally abnormal pregnancies and 377 matched controls. The median MSSP1 concentration in 48 Down's syndrome pregnancies was significantly elevated at 1.17 multiples of the control median (MOM), and significantly reduced (0.5 MOM) in a group of eight cases of unbalanced translocations. There was no significant difference in median SP1 concentrations in cases of trisomy 18, trisomy 13, balanced translocations, or sex chromosome abnormalities. A comparison with human chorionic gonadotrophin results in the same series of samples indicates that SP1 is a less sensitive predictor of Down's syndrome pregnancies.


Inotropic influence of macrocyclic polyethers on tracheal smooth muscle. Incubated guinea pig tracheal smooth muscle exhibited both positive and negative inotropic responses to a variety of crown ether analogs that ranged in size from 12-crown-4 to 30-crown-10 and included molecules whose lipophilicity was modified by the addition of benzo- and cyclohexo-substituents on the basic molecular framework. The inotropic influence of crown ethers may not only be due to their ionophoretic capabilities but may result from their ability to affect alterations in membrane physiology.


An assessment of the pharmacokinetics and pharmacodynamics of single doses of amlodipine in elderly normotensives. This study characterizes the single dose pharmacokinetic characteristics of the dihydropyridine calcium antagonist drug amlodipine in a group of 16 elderly subjects, aged 65 to 86 years (8 M:8 F). The most notable pharmacokinetic features were a prolonged terminal elimination half life of 48 +/- 16 hours and a delayed tmax of 7.3 +/- 1.3 hours. Consistent with the time to achieve peak plasma drug concentrations, there was a modest but significant reduction in blood pressure at 6-8 hours after dosing. Comparison of these results with those of published data for young subjects indicate not only a greater degree of intersubject variability but also a longer half life in the elderly, suggestive of reduced drug clearance, which may lead to higher plasma drug concentrations particularly at steady state.


Effects of cocaine alone and in combination with prazosin or ondansetron on multiple fixed-interval fixed-ratio performance in pigeons. Three pigeons were trained to respond on a two-component multiple schedule in which the components alternated regularly. In one component of the schedule, food was presented when the pigeon successfully completed a fixed-interval 120-s schedule within 150 s. In the other component of the schedule, food presentation occurred when the pigeon managed to complete a fixed-ratio 30 schedule within 30 s. Once responding had stabilized under both components of the schedule, pigeons were challenged with different doses of cocaine alone or cocaine in combination with 1.0 mg/kg prazosin (a selective alpha 1-adrenergic antagonist) or 0.10 or 0.50 mg/kg ondansetron (a selective 5-hydroxytryptamine3 antagonist). All drugs were injected intramuscularly 5 min before the start of selected experimental sessions. For two subjects, low doses of cocaine increased the low response rates maintained by the fixed-interval schedule while decreasing the high rates maintained by the fixed-ratio schedule. At intermediate doses, both high and low rates decreased but higher rates were more susceptible to disruption than low rates. The highest doses of cocaine completely eliminated responding in both schedule components. The high-rate behavior of the third subject was not affected by low or intermediate doses of cocaine, while low rates decreased at doses up to 5.6 mg/kg. The higher doses of cocaine eliminated responding in this subject as well. Prazosin and both doses of ondansetron antagonized the behavioral effects of cocaine at doses that ranged from 1.0-3.0 mg/kg. Redetermination of the dose-effect curve for cocaine at the conclusion of the experiment revealed that the curve had significantly shifted to the right.


Comparative study of the EEG profile of neuroleptics selective for D-1 or D-2 dopamine receptors in the rabbit. The neuroleptics SCH 23390 and raclopride, which interact selectively with either D-1 or D-2 dopamine receptor, were studied for their effects on electroencephalographic (EEG) activity in the rabbit. Haloperidol (0.3 and 1 mg/kg intravenously, i.v.), which was used for comparison, induced synchronization of the cortical EEG activity. Spectral EEG analysis showed increase of power in the whole frequency range (0.1-38.5 Hz) and in all frequency bands in the cortex, whereas a slight decrease of slow and fast theta activity (3.7-7.2 and 7.2-12.2 Hz) was observed in the hippocampus. Animals appeared sedated and arousal response to somatosensory stimuli was markedly inhibited. SCH 23390 (0.03 and 0.3 mg/kg i.v.) induced periods of cortical synchronization and changes of spectral power qualitatively similar to those accompanying haloperidol administration. The drug slightly reduced the duration of arousal elicited by stimuli. Raclopride (1 and 3 mg/kg i.v.) induced weak EEG changes and little effect on arousal response to stimulation. There was an increase of slow wave activity which was particularly evident in the hippocampus. The data indicate that, although to a lesser degree, the D-1 receptor antagonist SCH 23390 induced EEG effects similar to those of haloperidol, whereas blockade of D-2 receptors by raclopride resulted in different patterns of EEG activity.


A comparison of outcomes using three different methods of breast reconstruction. In a review of 325 postmastectomy breast reconstructions, the aesthetic quality of the result and the risk of unsuccessful outcome were compared for three techniques: tissue expansion (105 breasts), latissimus dorsi myocutaneous flap (47 breasts), and TRAM flap (173 breasts). The aesthetic successes achievable with the three methods were similar, and some excellent results were achieved with each of them. The failure rate after tissue expansion (21 percent) was significantly higher than those observed with the TRAM (3 percent) and latissimus (9 percent) flaps. Tissue expansion also was not as aesthetically successful as other techniques in obese patients. For immediate breast reconstruction, the TRAM flap was the most aesthetically successful technique. Although tissue expansion has advantages and may be the best choice for some patients, methods that used autogenous tissue provided more consistent success.