The phospholipase B homolog Plb1 is a mediator of osmotic stress response and of nutrient-dependent repression of sexual differentiation in the fission yeast Schizosaccharomyces pombe

Although phospholipase B (PLB) enzymes have been described in eukaryotes from yeasts to mammals, their biological functions are poorly understood. Here we describe the characterization of plb1, one of five genes predicted to encode PLB homologs in the fission yeast, Schizosaccharomyces pombe. The plb1 gene is dispensable under normal growth conditions but required for viability in high-osmolarity media and for normal osmotic stress-induced gene expression. Unlike mutants defective in function for the stress-activated MAP kinase Spc1, plb1Delta cells are not hypersensitive to oxidative or temperature stresses, nor do they undergo a G2-specific arrest in response to osmotic stress. In addition to defects in osmotic stress response, plb1Delta cells exhibit a cold-sensitive defect in nutrient-mediated mating repression, a phenotype reminiscent of mutants in the cyclic AMP (cAMP) pathway. We show that, like plb1Delta cells, mutants in the cAMP pathway are defective for growth in high-osmolarity media, demonstrating a previously unrecognized role for the cAMP pathway in osmotic stress response. Furthermore, we show that gain-of function in the cAMP pathway can rescue the osmosensitive growth defect of plb1Delta cells, suggesting that the cAMP pathway is a potential downstream target of the actions of Plb1 in S. pombe.

Adaptation of cardiac morphology and function to endurance and strength training. A comparative study using MR imaging and echocardiography in males and females

Left ventricular (LV) dimensions and function and maximal oxygen uptake (VO(2)max) were measured in endurance-trained (10 male, m, 10 female, f), strength-trained athletes (8 m, 10 f) and untrained subjects (9 m, 10 f). LV dimensions were measured using magnetic resonance imaging (MRI) and echocardiography and the results were equal irrespective of method. Endurance-trained m and f had significantly higher LV volumes and mass than both strength-trained and controls. No VO(2)max or dimensional differences were seen between strength-trained and untrained subjects. In endurance-trained males, LV volumes and mass/kg bw were higher than in endurance-trained females. There was no significant gender difference for strength-trained or untrained subjects regarding body weight-related heart dimensions. It is concluded that LV dimensions and volumes are strongly dependent on oxygen transport capacity in normal subjects practising different modes of training, and that the gender differences, if LV dimensions are related to aerobic work capacity, are smaller than previously reported.

Enzyme therapy for lysosomal acid lipase deficiency in the mouse

Lysosomal acid lipase (LAL) is the critical enzyme for the hydrolysis of the triglycerides (TG) and cholesteryl esters (CE) delivered to lysosomes. Its deficiency produces two human phenotypes, Wolman disease (WD) and cholesteryl ester storage disease (CESD). A targeted disruption of the LAL locus produced a null (lal( -/-)) mouse model that mimics human WD/CESD. The potential for enzyme therapy was tested using mannose terminated human LAL expressed in Pichia pastoris (phLAL), purified, and administered by tail vein injections to lal( -/-) mice. Mannose receptor (MR)-dependent uptake and lysosomal targeting of phLAL were evidenced ex vivo using competitive assays with MR-positive J774E cells, a murine monocyte/macrophage line, immunofluorescence and western blots. Following (bolus) IV injection, phLAL was detected in Kupffer cells, lung macrophages and intestinal macrophages in lal( -/-) mice. Two-month-old lal( -/-) mice received phLAL (1.5 U/dose) or saline injections once every 3 days for 30 days (10 doses). The treated lal( -/-) mice showed nearly complete resolution of hepatic yellow coloration; hepatic weight decreased by approximately 36% compared to PBS-treated lal( -/-) mice. Histologic analyses of numerous tissues from phLAL-treated mice showed reductions in macrophage lipid storage. TG and cholesterol levels decreased by approximately 50% in liver, 69% in spleen and 50% in small intestine. These studies provide feasibility for LAL enzyme therapy in human WD and CESD.

Synthesis and Diels-Alder reactions of 4-vinylimidazoles

[structure in text] The synthesis of several 4-vinylimidazoles via Stille cross-coupling reactions of the corresponding protected 4-iodoimidazoles with tributylvinylstannane is described. These heterocyclic dienes are shown to be effective partners in the Diels-Alder reaction, providing adducts in good yield and exhibiting useful levels of isomer selectivity and stereoselectivity (endo/exo).

[Clinical study: the effects of inhaling nitrous oxide for analgesia labor on pregnant women and fetus]

OBJECTIVE

To investigate the effect of the inhalation of nitrous oxide premixed with oxygen (50%:50%) for analgesia labor on maternal and fetus.

METHODS

A total of 100 cases of pregnant women were provided with nitrous oxide premixed with oxygen (50%:50%) (control group); Another 100 cases were provided only with oxygen (comparison group). Recording duration of the Labor, way of delivery, bleeding volume, Apgars score, blood gas analysis to maternal radius artery and fetal umbilical blood among all patients.

RESULTS

The effect for analgesia labor of the premixed gas was much better than that of control group, but there were no significant differences in time of labor, bleeding volume, Apgars score between the two groups.

CONCLUSIONS

The inhalation of nitrous oxide premixed with oxygen (50%:50%) for analgesia labor benefits pregnant women because of keeping them being a good mental and physical condition. The inhalation of nitrous oxide for analgesia labor is a safe, effective and easy method.

Par-4 is a synaptic protein that regulates neurite outgrowth by altering calcium homeostasis and transcription factor AP-1 activation

Although Par-4 (prostate apoptosis response-4) is involved in initiation of neurodegenerative cascades associated with certain neurodegenerative disorders, normal physiological roles of Par-4 in neurons have remained elusive. It was recently reported that Par-4 protein levels could be regulated at translational level in synaptic terminals following apoptotic insults, suggesting that Par-4 might play a role in synaptic function. We report that Par-4 is a synaptic protein preferably localized in postsynaptic density (PSD). The expression of Par-4 in synaptosome preparations and PSDs are developmentally and regionally regulated. Synaptic Par-4 is enriched in the cerebral cortex and the hippocampus, but not in the cerebellum. In vitro as well as in vivo experiments demonstrate that the levels of synaptic Par-4 increase as the neurons mature. Overexpression of Par-4 in transfected PC12 cells inhibits nerve growth factor (NGF)-induced cellular differentiation and neurite outgrowth by a mechanism involving aberrant elevation of intracellular calcium levels and suppression of activation of the transcription factor AP-1. The actions of Par-4 were consistently blocked by co-expression of the dominant negative regulator of Par-4 activity (the leucine zipper domain of Par-4). Since the leucine zipper domain of Par-4 (Leu.zip) may mediate protein--protein interactions, the results indicate that the actions of Par-4 require its interaction with other protein(s) or dimerization with itself. These results suggest that Par-4 may play an important role in postsynaptic signal transduction and regulation of cellular pathways associated with cellular differentiation and neurite outgrowth. Identification of Par-4 as a novel synaptic protein may have significant implications in understanding the mechanisms of synaptic functions in physiological and pathological settings.

Bob1, a Gim5/MM-1/Pfd5 homolog, interacts with the MAP kinase kinase Byr1 to regulate sexual differentiation in the fission yeast, Schizosaccharomyces pombe

The MAPKK Byr1 is an essential component of a Ras-dependent MAPK module required for sexual differentiation in the fission yeast, Schizosaccharomyces pombe. Here we describe the genetic and molecular characterization of a highly conserved protein, Bob1, which was identified from a two-hybrid screen for Byr1-interacting proteins. Byrl and Bobl proteins coprecipitate from S. pombe cell lysates, and both proteins localize to the tips and septa of S. pombe cells. S. pombe bob1 null (bob1delta) mutants lack obvious growth defects but exhibit a significant mating deficiency, which can be suppressed by overexpression of Byrl. Overexpression of Bob1 also leads to inhibition of mating in S. pombe, and this defect is likewise suppressed by Byrl overexpression. Bob1 is highly homologous in structure to the mammalian MM-1/Pfd5 and budding yeast Gim5/Pfd5-Sc proteins, which have been implicated as regulators of actin and tubulins. Similar to budding yeast gim5/pfd5-Sc mutants, S. pombe bob1delta cells have cytoskeletal defects, as judged by hypersensitivity to cytoskeletal disrupting drugs. byr1delta mutants do not share this characteristic with bob1delta mutants, and byr1delta bob1delta mutants are not significantly more sensitive to cytoskeletal disrupting drugs than cells carrying only the bob1delta mutation. Taken together, our results suggest that Bob1 has Byr1-related function(s) required for proper mating response of S. pombe cells and Byrl-independent function(s) required for normal cytoskeletal control. We show that the human MM-1/Pfd5 protein can substitute for its counterpart in fission yeast, providing evidence that the functions of Bob1-related proteins have been highly conserved through evolution. Our results lead us to propose that Bob1-related proteins may play diverse roles in eukaryotic organisms.

The mechanism of cerebral evoked potentials by repetitive magnetic stimulation of gastrocnemius muscle in Duchenne muscular dystrophy

OBJECTIVE

To study the features and mechanism of the cerebral evoked potentials by repetitive stimulation of calf muscle in Duchenne muscular dystrophy (DMD) patients with obvious muscular dystrophy and psuedohypertrophy.

METHODS

Cerebral evoked potentials by stimulation of calf muscles and somatosensory evoked potentials (SEPs) by the stimulation of posterior tibial nerves at ankle were measured in 10 patients with DMD and 10 normal controls matched with gender and age. The intensity of the magnetic stimulation was at 30% of maximal output (2.1 Tesla, MagPro magnetic stimulator, Dantec) and the frequency was 1 Hz. The low intensity of magnetic stimulation was just sufficient to produce a contraction of the muscle belly underneath the coil. Recording electrode was placed at 2 cm posterior to the Cz, reference to Fpz. The latencies of N33, P38, N48 and P55 and amplitude (P38 - N48) were recorded. SEPs were recorded by routine methods.

RESULTS

In normal subjects, the amplitudes of cerebral evoked potentials by magnetic stimulation of calf muscle was 40% lower than that by electrical stimulation of the posterior tibial nerves at ankle. The latency of P38 was 2.9 +/- 2.1 ms longer compared with electrical stimulation of the posterior tibial nerves at ankle. In 6 patients, P38 latency from magnetic stimulation was remarkably prolonged (P < 0.01), and in 4 patients, there was no remarkable response. SEPs evoked by electrical stimulation were normal in all of the patients.

CONCLUSION

DMD is an available model for the study of mechanism of cerebral evoked potentials by magnetic stimulating muscle. We can conclude that the responses from magnetic stimulation were produced by muscle input. The abnormal responses in patients may relate to decreased input of muscle by stimulating dystrophic and psedohypertrophic muscle.

Prostate apoptosis response-4 enhances secretion of amyloid beta peptide 1-42 in human neuroblastoma IMR-32 cells by a caspase-dependent pathway

Prostate apoptosis response-4 (Par-4) is a leucine zipper protein that promotes neuronal cell death in Alzheimer's disease (AD). Neuronal degeneration in AD may result from extracellular accumulation of amyloid beta peptide (Abeta) 1-42. To examine the effect of Par-4 on Abeta secretion and to reconcile amyloid/apoptosis hypotheses of AD, we generated IMR-32 cell lines that overexpress Par-4 and/or its leucine zipper domain. Overexpression of Par-4 did not significantly affect levels of the endogenously expressed beta amyloid precursor protein but drastically increased the Abeta(1-42)/Abeta(total) ratio in the conditioned media about 6-8 h after trophic factor withdrawal. Time course analysis of caspase activation reveals that Par-4 overexpression exacerbated caspase activation, which is detectable within 2 h after trophic factor withdrawal. Furthermore, inhibition of caspase activity by the broad spectrum caspase inhibitor BD-fmk significantly attenuated the Par-4-induced increase in Abeta 1-42 production. In addition, the effects of Par-4 on secretion of Abeta 1-42 were consistently blocked by co-expression of the leucine zipper domain, indicating that the effect of Par-4 on Abeta secretion may require its interaction with other protein(s). These results suggest that Par-4 increases secretion of Abeta 1-42 largely through a caspase-dependent pathway after apoptotic cascades are initiated.

The highly conserved protein methyltransferase, Skb1, is a mediator of hyperosmotic stress response in the fission yeast Schizosaccharomyces pombe

The p21-activated kinase, Shk1, is required for cell viability, establishment and maintenance of cell polarity, and proper mating response in the fission yeast, Schizosaccharomyces pombe. Previous genetic studies suggested that a presumptive protein methyltransferase, Skb1, functions as a positive modulator of Shk1. However, unlike Shk1, Skb1 is not required for viability or mating of S. pombe cells and contributes only modestly to the regulation of cell morphology under normal growth conditions. Here we demonstrate that Skb1 plays a more significant role in regulating cell growth and polarity under conditions of hyperosmotic stress. We provide evidence that the inability of skb1Delta cells to properly maintain cell polarity in hyperosmotic conditions results from inefficient subcellular targeting of F-actin. We show that Skb1 localizes to cell ends, sites of septation, and nuclei of S. pombe cells. Hyperosmotic shock results in substantial delocalization of Skb1 from cell ends and nuclei, as well as stimulation of Skb1 protein methyltransferase activity. Taken together, our results demonstrate a new role for Skb1 as a mediator of hyperosmotic stress response in fission yeast. We show that the protein methyltransferase activity of the human Skb1 homolog, Skb1Hs, is also stimulated by hyperosmotic stress in fission yeast, providing evidence for evolutionary conservation of a role for Skb1-related proteins as mediators of hyperosmotic stress response, as well as mechanisms involved in regulating this novel class of protein methyltransferases.

Genes regulating touch cell development in Caenorhabditis elegans

To identify genes regulating the development of the six touch receptor neurons, we screened the F(2) progeny of mutated animals expressing an integrated mec-2::gfp transgene that is expressed mainly in these touch cells. From 2638 mutated haploid genomes, we obtained 11 mutations representing 11 genes that affected the production, migration, or outgrowth of the touch cells. Eight of these mutations were in known genes, and 2 defined new genes (mig-21 and vab-15). The mig-21 mutation is the first known to affect the asymmetry of the migrations of Q neuroblasts, the cells that give rise to two of the six touch cells. vab-15 is a msh-like homeobox gene that appears to be needed for the proper production of touch cell precursors, since vab-15 animals lacked the four more posterior touch cells. The remaining touch cells (the ALM cells) were present but mispositioned. A similar touch cell phenotype is produced by mutations in lin-32. A more severe phenotype; i.e., animals often lacked ALM cells, was seen in lin-32 vab-15 double mutants, suggesting that these genes acted redundantly in ALM differentiation. In addition to the touch cell abnormalities, vab-15 animals variably exhibit embryonic or larval lethality, cell degenerations, malformation of the posterior body, uncoordinated movement, and defective egg laying.

Genetic and molecular characterization of Skb15, a highly conserved inhibitor of the fission yeast PAK, Shk1

The p21-activated kinase, Shk1, is essential for viability, establishment and maintenance of cell polarity, and proper mating response in the fission yeast, Schizosaccharomyces pombe. Here we describe the characterization of a highly conserved, WD repeat protein, Skb15, which negatively regulates Shk1 in fission yeast. A null mutation in the skb15 gene is lethal and results in deregulation of actin polymerization and localization, microtubule biogenesis, and the cytokinetic machinery, as well as a substantial uncoupling of these processes from the cell cycle. Loss of Skb15 function is suppressed by partial loss of Shk1, demonstrating that negative regulation of Shk1 by Skb15 is required for proper execution of cytoskeletal remodeling and cytokinetic functions. A mouse homolog of Skb15 can substitute for its counterpart in fission yeast, demonstrating that Skb15 protein function has been substantially conserved through evolution.

Lysosomal acid lipase-deficient mice: depletion of white and brown fat, severe hepatosplenomegaly, and shortened life span

Lysosomal acid lipase (LAL) is essential for the hydrolysis of triglycerides (TG) and cholesteryl esters (CE) in lysosomes. A mouse model created by gene targeting produces no LAL mRNA, protein, or enzyme activity. The lal-/- mice appear normal at birth, survive into adulthood, and are fertile. Massive storage of TG and CE is observed in adult liver, adrenal glands, and small intestine. The age-dependent tissue and gross progression in this mouse model are detailed here. Although lal-/- mice can be bred to give homozygous litters, they die at ages of 7 to 8 months. The lal-/- mice develop enlargement of a single mesenteric lymph node that is full of stored lipids. At 6;-8 months of age, the lal-/- mice have completely absent inguinal, interscapular, and retroperitoneal white adipose tissue. In addition, brown adipose tissue is progressively lost. The plasma free fatty acid levels are significantly higher in lal-/- mice than age-matched lal+/+ mice, and plasma insulin levels were more elevated upon glucose challenge. Energy intake was also higher in lal-/- male mice, although age-matched body weights were not significantly altered from age-matched lal+/+ mice. Early in the disease course, hepatocytes are the main storage cell in the liver; by 3;-8 months, the lipid-stored Kupffer cells progressively fill the liver. The involvement of macrophages throughout the body of lal-/- mice provide evidence for a critical nonappreciated role of LAL in cellular cholesterol and fatty acid metabolism, adipocyte differentiation, and fat mobilization.

Phenotypic correction of lipid storage and growth arrest in wolman disease fibroblasts by gene transfer of lysosomal acid lipase

Wolman disease is a lethal lysosomal storage disease due to deficiency of lysosomal acid lipase (LAL). Wolman disease is characterized by pronounced hepatic involvement while neurological symptoms are uncommon, making Wolman disease an attractive candidate for liver-directed gene therapy. This study was performed to test the effects of gene replacement in fibroblasts lacking LAL, using a recombinant adenovirus encoding the human LAL cDNA (AdhLAL). Human fibroblasts from a Wolman disease patient were infected with AdhLAL and showed a dose-dependent increase in LAL protein and activity up to 5-fold above levels in control fibroblasts. Furthermore, 72 hr after infection with AdhLAL there was a dose-dependent correction of the severe lipid storage phenotype of Wolman disease fibroblasts. Electron microscopy confirmed significant correction of the lysosomal lipid storage in AdhLAL-infected Wolman disease fibroblasts at the ultrastructural level. Intravenous injection of AdhLAL into wild-type mice resulted in a 13.5-fold increase in hepatic LAL activity, and overexpression of LAL was not associated with toxic side effects. These data demonstrate high-level lysosomal expression of recombinant LAL in vitro and in vivo and show the feasibility of gene therapeutic strategies for the treatment of Wolman disease.

Yeast U1 snRNP-pre-mRNA complex formation without U1snRNA-pre-mRNA base pairing

Base pairing between the 5' end of U1 snRNA and the conserved 5' splice site of pre-mRNA is important for commitment complex formation in vitro. However, the biochemical mechanisms by which pre-mRNA is initially recognized by the splicing machinery is not well understood. To evaluate the role of this base pairing interaction, we truncated U1 snRNA to eliminate the RNA-RNA interaction and surprisingly found that U1 snRNP can still form a nearly normal RNA-protein complex and maintain sequence specificity. We propose that some feature of U1 snRNP, perhaps one or more protein factors, is more important than the base pairing for initial 5' splice site recognition. In addition, at least five sets of interactions contribute to complex formation or stability. Only one of these is base pairing between the 5' splice site and the 5' end of U1 snRNA, without which the U1 snRNP-pre-mRNA complex is less stable and has a somewhat altered conformation.

[T cell and molecule-1 detection in cornea of fetus, neonates, children and adults]

OBJECTIVE

To study the immune state of human cornea with different ages.

METHODS

The human corneas in different ages were detected by using immunohistochemical techniques for 5 types of monoclonal antibody.

RESULTS

The contents of T-cell (CD(+)(3)), helper/inducer (CD(+)(4)), toxic T-cell (CD(+)(8)), macrophage (CD(+)(68)) and molecule-1 (intercellular adhesive molecule, CD(+)(54)) in the adult cornea were relatively low, mainly in the limbus but none at the corneal center. These positive cells were less in corneas of fetus, neonates and children than that in adults.

CONCLUSION

In corneas of fetus, neonates and children, the T-cell, macrophage and molecule-1 were less than that of adults. Their corneas may be used as donors in corneal transplantation.

Sequence and analysis of chromosome 5 of the plant Arabidopsis thaliana

The genome of the model plant Arabidopsis thaliana has been sequenced by an international collaboration, The Arabidopsis Genome Initiative. Here we report the complete sequence of chromosome 5. This chromosome is 26 megabases long; it is the second largest Arabidopsis chromosome and represents 21% of the sequenced regions of the genome. The sequence of chromosomes 2 and 4 have been reported previously and that of chromosomes 1 and 3, together with an analysis of the complete genome sequence, are reported in this issue. Analysis of the sequence of chromosome 5 yields further insights into centromere structure and the sequence determinants of heterochromatin condensation. The 5,874 genes encoded on chromosome 5 reveal several new functions in plants, and the patterns of gene organization provide insights into the mechanisms and extent of genome evolution in plants.

Bonding, structure, and energetics of gaseous E8(2+) and of solid E8(AsF6)2 (E = S, Se)

The attempt to prepare hitherto unknown homopolyatomic cations of sulfur by the reaction of elemental sulfur with blue S8(AsF6)2 in liquid SO2/SO2ClF, led to red (in transmitted light) crystals identified crystallographically as S8(AsF6)2. The X-ray structure of this salt was redetermined with improved resolution and corrected for librational motion: monoclinic, space group P2(1)/c (No. 14), Z = 8, a = 14.986(2) A, b = 13.396(2) A, c = 16.351(2) A, beta = 108.12(1) degrees. The gas phase structures of E8(2+) and neutral E8 (E = S, Se) were examined by ab initio methods (B3PW91, MPW1PW91) leading to delta fH theta[S8(2+), g] = 2151 kJ/mol and delta fH theta[Se8(2+), g] = 2071 kJ/mol. The observed solid state structures of S8(2+) and Se8(2+) with the unusually long transannular bonds of 2.8-2.9 A were reproduced computationally for the first time, and the E8(2+) dications were shown to be unstable toward all stoichiometrically possible dissociation products En+ and/or E4(2+) [n = 2-7, exothermic by 21-207 kJ/mol (E = S), 6-151 kJ/mol (E = Se)]. Lattice potential energies of the hexafluoroarsenate salts of the latter cations were estimated showing that S8(AsF6)2 [Se8(AsF6)2] is lattice stabilized in the solid state relative to the corresponding AsF6- salts of the stoichiometrically possible dissociation products by at least 116 [204] kJ/mol. The fluoride ion affinity of AsF5(g) was calculated to be 430.5 +/- 5.5 kJ/mol [average B3PW91 and MPW1PW91 with the 6-311 + G(3df) basis set]. The experimental and calculated FT-Raman spectra of E8(AsF6)2 are in good agreement and show the presence of a cross ring vibration with an experimental (calculated, scaled) stretching frequency of 282 (292) cm-1 for S8(2+) and 130 (133) cm-1 for Se8(2+). An atoms in molecules analysis (AIM) of E8(2+) (E = S, Se) gave eight bond critical points between ring atoms and a ninth transannular (E3-E7) bond critical point, as well as three ring and one cage critical points. The cage bonding was supported by a natural bond orbital (NBO) analysis which showed, in addition to the E8 sigma-bonded framework, weak pi bonding around the ring as well as numerous other weak interactions, the strongest of which is the weak transannular E3-E7 [2.86 A (S8(2+), 2.91 A (Se8(2+)] bond. The positive charge is delocalized over all atoms, decreasing the Coulombic repulsion between positively charged atoms relative to that in the less stable S8-like exo-exo E8(2+) isomer. The overall geometry was accounted for by the Wade-Mingos rules, further supporting the case for cage bonding. The bonding in Te8(2+) is similar, but with a stronger transannular E3-E7 (E = Te) bonding. The bonding in E8(2+) (E = S, Se, Te) can also be understood in terms of a sigma-bonded E8 framework with additional bonding and charge delocalization occurring by a combination of transannular n pi *-n pi * (n = 3, 4, 5), and np2-->n sigma * bonding. The classically bonded S8(2+) (Se8(2+) dication containing a short transannular S(+)-S+ (Se(+)-Se+) bond of 2.20 (2.57) A is 29 (6) kJ/mol higher in energy than the observed structure in which the positive charge is delocalized over all eight chalcogen atoms.

Par-4 induces cholinergic hypoactivity by suppressing ChAT protein synthesis and inhibiting NGF-inducibility of ChAT activity

Profound reductions in choline acetyl-transferase (ChAT) activity are reliable markers for cholinergic hypoactivity associated with cognitive function deficit in Alzheimer's disease (AD). Par-4 (prostate apoptosis response-4) is a novel mediator of neuronal apoptosis associated with the pathogenesis of AD. Par-4 contains a leucine zipper domain (Leu.zip) that presumably mediates protein-protein interactions critical for its functions in apoptosis. Par-4 activity can be effectively blocked by overexpression of Leu. zip because it exerts a dominant negative action possibly by competitively blocking the interaction of Par-4 with other proteins. Whether Par-4 participates in regulation of cholinergic signaling has not been determined. We report that overexpression of Par-4 results in apoptotic and non-apoptotic reductions in ChAT activity in transfected PC12 cells following exposure to a toxic concentration (50 microM) of aggregated amyloid beta peptide 1-42 (Abeta 1-42) and a non-toxic concentration (1 microM) of soluble Abeta 1-42, respectively. Non-apoptotic reduction in ChAT activity induced by Par-4 can be completely blocked by co-overexpression of Leu.zip, indicating that enhanced Par-4 activity is a necessary event for cholinergic hypoactivity in PC12 cells. Further studies found that Par-4 induces non-apoptotic reduction in ChAT activity by: (1) reducing ChAT protein levels following exposure to non-toxic concentration of Abeta, and (2) blocking the cellular capability to increase ChAT activity following exposure to nerve growth factor (NGF). The role of Par-4 in inducing cholinergic hypoactivity may have significant implications in the understanding and the treatment of memory impairment in AD.

[Identification of high-lying odd energy levels of uranium by resonant ionization mass spectrometry]

Single-colour and two-colour multiphoton resonant ionization spectra of uranium atom were studied extensively with a Nd:YAG laser-pumped dye laser atomic beam apparatus time-of-flight mass spectrometer in our laboratory. The energy locations of high-lying odd-parity levels in the region 33,003-34,264 cm-1, measured by a two-colour three-step ionization technique, were reported here. The angular momentum quantum number J was uniquely assigned for these levels by using angular momentum selection rules.

Receptor-dependent cell stress and amyloid accumulation in systemic amyloidosis

Accumulation of fibrils composed of amyloid A in tissues resulting in displacement of normal structures and cellular dysfunction is the characteristic feature of systemic amyloidoses. Here we show that RAGE, a multiligand immunoglobulin superfamily cell surface molecule, is a receptor for the amyloidogenic form of serum amyloid A. Interactions between RAGE and amyloid A induced cellular perturbation. In a mouse model, amyloid A accumulation, evidence of cell stress and expression of RAGE were closely linked. Antagonizing RAGE suppressed cell stress and amyloid deposition in mouse spleens. These data indicate that RAGE is a potential target for inhibiting accumulation of amyloid A and for limiting cellular dysfunction induced by amyloid A.

The bradykinin type 2 receptor is a target for p53-mediated transcriptional activation

The bradykinin type 2 receptor (BK2) is a developmentally regulated G protein-coupled receptor that mediates diverse actions such as vascular reactivity, salt and water excretion, inflammatory responses, and cell growth. However, little is known regarding regulation of the BK2 gene. We report here that the rat BK2 receptor is transcriptionally regulated by the tumor suppressor protein p53. The 5'-flanking region of the rat BK2 gene contains two p53-like binding sites: a sequence at -70 base pairs (P1 site) that is conserved in the murine and human BK2 genes; and a sequence at -707 (P2) that is not. The P1 and P2 motifs bind specifically to p53, as assessed by gel mobility shift assays. Transient transfection into HeLa cells of a CAT reporter construct driven by 1.2-kilobases of the BK2 gene 5'-flanking region demonstrated that the BK2 promoter is dose dependently activated by co-expression of wild-type p53. Co-expression of a dominant negative mutant p53 suppresses the activation of BK2 by wild-type p53. Promoter truncation localized the p53-responsive element to the region between -38 and -94 base pairs encompassing the p53-binding P1 sequence. Furthermore, p53-mediated activation of the BK2 promoter is augmented by the transcriptional co-activators, CBP/p300. Interestingly, removal of the P2 site by truncation or site-directed deletion amplifies p53-mediated activation of the BK2 promoter. These results demonstrate that the rat BK2 promoter is a target for p53-mediated activation and suggest a new physiological role for p53 in the regulation of G protein-coupled receptor gene expression.

[Validation of a method to inactivate fentanyl in the used devices of Durogesic]

A recent literature study has shown that after 3 days of use of a transdermic patch of fentanyl (Durogésic(R)), there was such an amount of drug remaining that may make its excessive use possible. First of all, we have developed a fentanyl assay by a spectrophotometric method and then, the remaining amount of fentanyl was determined in 29 used patches. This study has shown that a mean of 22% of fentanyl remained in the used patches, each original content astounded. Then, we have determined an easy and feasible method in a chemist's shop allowing inactivation of fentanyl in the used patches and so preventing its diversion.

[Study on role of metallothionein in anticancer effect of copper green on treatment of experimental hepatocarcinoma in mice]

OBJECTIVE

To study the role of metallothionein (MT) in the anticancer effect of copper green on experimental hepatoma (H22) in mice.

METHODS

Atomic absorbency spectrometry (AAS), silver saturation method and histochemistry method were used to study the content and distribution of copper and MT in liver and tumor tissues.

RESULTS

(1) Both copper and MT contents in liver tissue of the copper treated group were significantly higher than that of the control group (P < 0.001 in both). (2) Copper content in tumor tissue of the treated group was higher whereas MT content was markedly lower than that of the control group (P < 0.001). (3) Histochemical examination showed that in the copper treated group, both copper and MT existed simultaneously in plasma and nuclei of liver cells, while in the tumor tissue, rich in copper but few or negative in MT existed.

CONCLUSION

(1) In liver tissue, large amount of MT is coupled with copper which is helpful to protect liver from the damage of copper. (2) The decrease of MT in tissue of tumor could be beneficial for copper to exert full effect in killing tumor cell.

[The application of polymerase chain reaction-single strain conformation polymorphism in the pedigree analysis of familial hypercholerolemia patients]

OBJECTIVE

To discuss the value of polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP) in the pedigree analysis of familial hypercholesterolemia(FH) patients.

METHODS

For 4 patients with FH detected by PCR-SSCP and DNA sequence analysis (1 homozygote has point mutation in exon 7, 1 heterozygote in exon 14, and 2 heterozygotes in 3' part of exon 4 ), members of each pedigree, altogether 23 individuals, were analysed using PCR-SSCP.

RESULTS

Every member of the 4 pedigrees was examined genetically. Besides the 4 probands, another 1 homozygote and 8 heterozygotes were found.

CONCLUSION

The PCR-SSCP method can be used in the pedigree analysis of FH probands. The early diagnosis of siblings and relatives can help to provide genetic consultation and direction so as to pay attention to development of hypercholesterolemia.

trp RNA-binding attenuation protein-5' stem-loop RNA interaction is required for proper transcription attenuation control of the Bacillus subtilis trpEDCFBA operon

The trp RNA-binding attenuation protein (TRAP) regulates expression of the Bacillus subtilis trpEDCFBA operon by a novel transcription attenuation mechanism. Tryptophan-activated TRAP binds to the nascent trp leader transcript by interacting with 11 (G/U)AG repeats, 6 of which are present in an antiterminator structure. TRAP binding to these repeats prevents formation of the antiterminator, thereby promoting formation of an overlapping intrinsic terminator. A third stem-loop structure that forms at the extreme 5' end of the trp leader transcript also plays a role in the transcription attenuation mechanism. The 5' stem-loop increases the affinity of TRAP for trp leader RNA. Results from RNA structure mapping experiments demonstrate that the 5' stem-loop consists of a 3-bp lower stem, a 5-by-2 asymmetric internal loop, a 6-bp upper stem, and a hexaloop at the apex of the structure. Footprinting results indicate that TRAP interacts with the 5' stem-loop and that this interaction differs depending on the number of downstream (G/U)AG repeats present in the transcript. Expression studies with trpE'-'lacZ translational fusions demonstrate that TRAP-5' stem-loop interaction is required for proper regulation of the trp operon. 3' RNA boundary experiments indicate that the 5' structure reduces the number of (G/U)AG repeats required for stable TRAP-trp leader RNA association. Thus, TRAP-5' stem-loop interaction may increase the likelihood that TRAP will bind to the (G/U)AG repeats in time to block antiterminator formation.

[Studies on the stable integration and expression of IL-2R alpha gene in CHO cells and it's applications]

OBJECTIVES

To establish a novel bioassay method for quantitative analysis of human IL-2 based on the specific binding of Interleukin-2 receptor alpha subunit (IL-2R alpha) with IL-2.

METHODS

Southern blot hybridization was first used to detect the stability of integration of recombinant secretive IL-2R alpha (rsIL-2R alpha) gene into the genome of highly expressed cell line reported elsewhere; the apparent Mr of the rsIL-2R alpha was then determined by using Western blotting; finally, a receptor-antibody sandwich ELISA method has been established for quantitative analysis of IL-2.

RESULTS

(1) Stable integration of rsIL-2R alpha gene into the genome of #17 CHO cell line has been identified; (2) the apparent Mr of rsIL-2R alpha was approximately 40,000; (3) linear range of the standard curve obtained from the receptor-based ELISA fell between 31.25-500 U of IL-2 (r = 0.9995). The slop of the standard curve decreased significantly when IL-2 was pre-incubated with goat anti-IL-2 antibody IgG (P < 0.01).

CONCLUSIONS

An IL-2R alpha-based IL-2 ELISA has been established for laboratory and clinical use with advantages of accuracy, specificity and simplicity over other conventional bioassays for IL-2 detection.

[The multicolour three-photon resonant ionization spectrum studies in uranium atom]

The multicolour three-photon resonant ionization spectra of 238U were measured by using the pulsed dye lasers system synchronously pumped by a frequency doubled Nd:YAG-laser 532 nm output(operated at 10 Hz), a device for atomic beam of U, time-of-flight mass spectrometer and boxcar integrator. The dye laser pulses have a 6 ns duration. Beams from the dye lasers, which have the same polarization direction and are focused by lenses, entered an interaction chamber through opposite windows on a common axis and spatially overlapped the U atomic beam. The optical pulse from dye laser DL2 was delayed to arrive at the interaction region 8 ns after the pulse from dye laser DL1; in the same way, the pulse from DL3 was delayed 8 ns after from DL2. The atomic beam device was made from stainless steel. We generated the U vapor by heating solid U in a graphite crucible by e-type electron-field on first excited states were studied in uranium atom. The question how to determine single-colour, two-colour and three-colour three-photon resonant ionization peak in the three-colour three-photon resonant ionization spectra diagram were solved.

Sequence and analysis of chromosome 4 of the plant Arabidopsis thaliana

The higher plant Arabidopsis thaliana (Arabidopsis) is an important model for identifying plant genes and determining their function. To assist biological investigations and to define chromosome structure, a coordinated effort to sequence the Arabidopsis genome was initiated in late 1996. Here we report one of the first milestones of this project, the sequence of chromosome 4. Analysis of 17.38 megabases of unique sequence, representing about 17% of the genome, reveals 3,744 protein coding genes, 81 transfer RNAs and numerous repeat elements. Heterochromatic regions surrounding the putative centromere, which has not yet been completely sequenced, are characterized by an increased frequency of a variety of repeats, new repeats, reduced recombination, lowered gene density and lowered gene expression. Roughly 60% of the predicted protein-coding genes have been functionally characterized on the basis of their homology to known genes. Many genes encode predicted proteins that are homologous to human and Caenorhabditis elegans proteins.

[Study on the posterior vitreous detachment in patients with high myopia]

OBJECTIVE

To access the development of posterior vitreous detachment(PVD) related to age, axial length of the eye, vitreous changes as well as the myopic chorioretinal manifestation in patients with high myopia.

METHODS

The vitreous status of 61 consecutive patients with high myopia(> or = -8.0 D and axial length > or = 26.0 mm) 110 eyes and 68 controls (< or = -3.0 D) 119 eyes were examined with biomicroscopic slit lamp and B-scan ultrasound. The myopic chorioretinal changes at the posterior pole were examined by indirect ophthalmoscope. The axial length of the eye was measured by A-scan ultrasound. The incidence of PVD was evaluated by Chi-square test.

RESULTS

The incidence of PVD in patients with high myopia increased with age. Its overall incidence was significantly higher than that in the controls (78.2% vs 31.1%, P < 0.001). In addition, the onset of PVD in patients with high myopia occurred much earlier in age than that in the control group. Axial length was an important factor responsible for the development of PVD in patients with high myopia. The incidence of PVD and age were highly correlated (r = 0.9997, P < 0.05). Retinal detachment occurred in 5 eyes in the patients with high myopia.

CONCLUSIONS

The results in the present study suggested that the incidence of PVD in patients with high myopia, increased with axial length of the eye and age. Vitreous changes are characteristic findings associated with high myopia, which was also involved in the development of PVD.

Unique cellular events occurring during the initial interaction of macrophages with matrix-retained or methylated aggregated low density lipoprotein (LDL). Prolonged cell-surface contact during which ldl-cholesteryl ester hydrolysis exceeds ldl protein degradation

A critical event in atherogenesis is the interaction of arterial wall macrophages with subendothelial lipoproteins. Although most studies have investigated this interaction by incubating cultured macrophages with monomeric lipoproteins dissolved in media, arterial wall macrophages encounter lipoproteins that are mostly bound to subendothelial extracellular matrix, and these lipoproteins are often aggregated or fused. Herein, we utilize a specialized cell-culture system to study the initial interaction of macrophages with aggregated low density lipoprotein (LDL) bound to extracellular matrix. The aggregated LDL remains extracellular for a relatively prolonged period of time and becomes lodged in invaginations in the surface of the macrophages. As expected, the degradation of the protein moiety of the LDL was very slow. Remarkably, however, hydrolysis of the cholesteryl ester (CE) moiety of the LDL was 3-7-fold higher than that of the protein moiety, in stark contrast to the situation with receptor-mediated endocytosis of acetyl-LDL. Similar results were obtained using another experimental system in which the degradation of aggregated LDL protein was delayed by LDL methylation rather than by retention on matrix. Additional experiments indicated the following properties of this interaction: (a) LDL-CE hydrolysis is catalyzed by lysosomal acid lipase; (b) neither scavenger receptors nor the LDL receptor appear necessary for the excess LDL-CE hydrolysis; and (c) LDL-CE hydrolysis in this system is resistant to cellular potassium depletion, which further distinguishes this process from receptor-mediated endocytosis. In summary, experimental systems specifically designed to mimic the in vivo interaction of arterial wall macrophages with subendothelial lipoproteins have demonstrated an initial period of prolonged cell-surface contact in which CE hydrolysis exceeds protein degradation.

A 5' RNA stem-loop participates in the transcription attenuation mechanism that controls expression of the Bacillus subtilis trpEDCFBA operon

The trp RNA-binding attenuation protein (TRAP) regulates expression of the Bacillus subtilis trpEDCFBA operon by transcription attenuation. Tryptophan-activated TRAP binds to the nascent trp leader transcript by interacting with 11 (G/U)AG repeats. TRAP binding prevents formation of an antiterminator structure, thereby promoting formation of an overlapping terminator, and hence transcription is terminated before RNA polymerase can reach the trp structural genes. In addition to the antiterminator and terminator, a stem-loop structure is predicted to form at the 5' end of the trp leader transcript. Deletion of this structure resulted in a dramatic increase in expression of a trpE'-'lacZ translational fusion and a reduced ability to regulate expression in response to tryptophan. By introducing a series of point mutations in the 5' stem-loop, we found that both the sequence and the structure of the hairpin are important for its regulatory function and that compensatory changes that restored base pairing partially restored wild-type-like expression levels. Our results indicate that the 5' stem-loop functions primarily through the TRAP-dependent regulatory pathway. Gel shift results demonstrate that the 5' stem-loop increases the affinity of TRAP for trp leader RNA four- to fivefold, suggesting that the 5' structure interacts with TRAP. In vitro transcription results indicate that this 5' structure functions in the attenuation mechanism, since deletion of the stem-loop caused an increase in transcription readthrough. An oligonucleotide complementary to a segment of the 5' stem-loop was used to demonstrate that formation of the 5' structure is required for proper attenuation control of this operon.

Colloidal bismuth pectin: an alternative to bismuth subcitrate for the treatment of Helicobacter pylori--positive duodenal ulcer

BACKGROUND

Bismuth triple therapy provides consistently good results in Helicobacter pylori eradication worldwide, whereas quadruple therapy using a combination of omeprazole and bismuth triple regimen has produced cure rates in excess of 90%. The prevalence of metronidazole-resistant strains was 26.8% in our area. Colloidal bismuth pectin (CBP) is a new, lower-priced bismuth salt made in China. The purpose of this study was to investigate the efficacy and safety of CBP triple and quadruple regimens in the treatment of H. pylori-positive duodenal ulcer.

MATERIALS AND METHODS

In this prospective trial, 205 patients with H. pylori-positive duodenal ulcer were allocated randomly to receive one of four regimens: metronidazole, 200 mg; amoxicillin, 250 mg; and colloidal bismuth subcitrate (CBS), 120 mg (group 1), or CBP, 100 mg qid (group 2) for 2 weeks, then continued CBS, 240 mg, or CBP, 200 mg bid for a further 2 weeks. A quadruple regimen using a combination of omeprazole, 20 mg bid, and CBS triple therapy (group 3) or CBP triple therapy (group 4), respectively, was given to patients for 1 week, followed by omeprazole, 20 mg once daily for a further 3 weeks. Further endoscopy was performed at least 4 weeks after cessation of the treatment. H. pylori status was determined by histology, a 14C urea breath test, and a urease test.

RESULTS

The per-protocol H. pylori cure rates were 85% (22 of 26 patients), 90% (35 of 39), 96% (46 of 48), and 95% (75 of 79) for groups 1 through 4. In the intention-to-treat analysis, cure rates were 79% (22 of 28), 83% (35 of 42), 90% (46 of 51), and 89% (75 of 84), respectively. The cure rates of quadruple therapy were higher than those of triple therapy; an 8.2% difference was not statistically significant (95% confidence interval [CI], 2.3-18.7%). The ulcer-healing rates were 88%, 87%, 98%, and 97%, respectively, for groups 1 through 4. The ulcer pain was relieved more rapidly in quadruple- than in triple-therapy regimens. Two patients discontinued treatment prematurely owing to drug-related side effects.

CONCLUSION

One-week quadruple therapy is highly effective and safe in H. pylori eradication in Chinese patients. CBP is as effective as CBS.

[Use PCR technique to detect mitochondrial DNA in rat membranous labyrinth]

OBJECTIVE

To establish a sensitive and reliable method of mtDNA detection in the membranous labyrinth of rat inner ear.

METHOD

A mtDNA segment of 601 bp containing the genes which encode ND1 subunit 16S rRNA in rat inner ear membranous labyrinth was detected by PCR method. The method is compared with Edris's mtDNA isolation method.

RESULT

A 601 bp PCR product of mtDNA in the membranous labyrinth of rat ear inner can be obtained by the two methods. But the requirement of the sample quantities was different for the two methods. The extraction of mtDNA need two of inner ears membranous labyrinth to get reliably result by the method adapted from Seidman. However, the mtDNA extraction procedure from Edris's method need six of inner ears of the in order to get reliably result.

CONCLUSION

The method of mtDNA isolation, amplification and detection membranous labyrinth of rat inner ear by PCR method adapted from seidman is more sersitive.

Immunocytochemical study of cells in the vitreous of proliferative vitreoretretinopathy

PURPOSE

To identify the cellular components of vitreous samples obtained during vitrectomy for proliferative vitreoretinopathy (PVR).

METHODS

With the use of three intermediate filament (IF) proteins, vimentin, glial fibrillary acidic protein (GFAP), and cytokeratin (CK), cytocentrifuge slides of 14 fresh vitreous aspirates were detected with immunohistochemical technique.

RESULTS

All the specimens contained epithelial-like proliferative cells with or without pigment and some membrane-like pieces. Immunocytochemical staining showed that 76.0-90.0% cells stained for CK, 17.4-29.6% cells expressed GFAP, and 80.1-91.0% cells were positive for vimentin.

CONCLUSIONS

Majority of cells in the vitreous samples originated from retinal pigment epithelial cells (RPE) and glial cells in PVR. Expression of IF proteins may be determined by tissue of origin and local microenvironment.

[The design of an ultrasonics Doppler spectrum analysis system for fetal umbilical blood flow monitoring]

This paper explains the design of an Ultrasonics Doppler Spectrum Analysis System for fetal umbilical blood flow monitoring. The gist of discussion includes the sampling method of the Doppler signals and the algorithm of the blood flow parameters. Because the DSP chip is not used in the AD cardboard, the hardware design is simplified and the system works steadily. In the process of computing the blood flow paramenters, an autochange method of the amplitude threshold and a timeout control technology are used, so the algorithm has good adaptability and works very stable.

[Chemical constituents of Cichorium intybus L]

OBJECTIVE

To investigate the chemical constituents of Cichorium intybus.

METHOD

Constituents were separated by means of solvent extraction and chromatography on silical gel. The structures were established by spectral analysis and chemical evidence.

RESULT

Seven compounds were isolated from the roots of C. intybus and four of them were identified as alpha-amyrin, taraxerone, baurenyl acetate and beta-sitosterol.

CONCLUSION

All the four compounds were obtained from the plant for the first time.

Targeted disruption of the mouse lysosomal acid lipase gene: long-term survival with massive cholesteryl ester and triglyceride storage

Lysosomal acid lipase (LAL) is essential for the hydrolysis of the triglycerides and cholesteryl esters in lysosomes. Its deficiency produces two phenotypes, a severe infantile-onset variant, Wolman disease (WD), and a later onset variant, cholesteryl ester storage disease (CESD). A mouse model with a LAL null mutation was produced by targeting disruption of the mouse gene. Homozygote knockout mice (lal -/lal-) produce no LAL mRNA, protein or enzyme activity. The lal-/lal- mice are born in Mendelian ratios, are normal appearing at birth, and follow normal development into adulthood. However, massive accumulation of triglycerides and cholesteryl esters occurs in several organs. By 21 days, the liver develops a yellow-orange color and is approximately 1.5-2.0x larger than normal. The accumulated cholesteryl esters and triglycerides are approximately 30-fold greater than normal. The lal+/lal- mice have approximately 50% of normal LAL activity and do not show lipid accumulation. Male and female lal-/lal- mice are fertile and can be bred to produce progeny. This mouse model is a phenotypic model of human CESD, and a biochemical and histopathologic mimic of human WD. The lal-/lal- mice provide a model to determine the role of LAL in lipid metabolism and the pathogenesis of its deficiency states.

trp RNA-binding attenuation protein-mediated long distance RNA refolding regulates translation of trpE in Bacillus subtilis

Expression of the trpEDCFBA operon is regulated at both the transcriptional and translational levels by the trp RNA-binding attenuation protein (TRAP) of Bacillus subtilis. When cells contain sufficient levels of tryptophan to activate TRAP, the protein binds to trp operon transcripts as they are being synthesized, most often causing transcription termination. However, termination is never 100% efficient, and transcripts that escape termination are subject to translational control. We determined that TRAP-mediated translational control of trpE can occur via a novel RNA conformational switch mechanism. When TRAP binds to the 5'-untranslated leader segment of a trp operon read-through transcript, it can disrupt a large secondary structure containing a portion of the TRAP binding target. This promotes refolding of the RNA such that the trpE Shine-Dalgarno sequence, located more than 100 nucleotides downstream from the TRAP binding site, becomes sequestered in a stable RNA hairpin. Results from cell-free translation, ribosome toeprint, and RNA structure mapping experiments demonstrate that formation of this structure reduces TrpE synthesis by blocking ribosome access to the trpE ribosome binding site. The role of the Shine-Dalgarno blocking hairpin in controlling translation of trpE was confirmed by examining the effect of multiple nucleotide substitutions that abolish the structure without altering the Shine-Dalgarno sequence itself. The possibility of protein-mediated RNA refolding as a general mechanism in controlling gene expression is discussed.

Molecular and enzymatic analyses of lysosomal acid lipase in cholesteryl ester storage disease

Human lysosomal acid lipase (hLAL) is essential for the hydrolysis of cholesteryl esters and triglycerides in the lysosome. Defective hLAL activity leads to two autosomal recessive traits, Wolman disease (WD) or cholesteryl ester storage disease (CESD). Phenotypically, WD has accumulation of both triglycerides and cholesteryl esters, while CESD has mainly elevated cholesteryl esters. We characterized mutations in the hLAL gene from two CESD siblings. By reverse transcriptase-PCR (RT-PCR) and cDNA cloning and sequencing, we identified homozygous deletion mutations of nucleotides 863 to 934, in the hLAL transcript. Normal levels of LAL mRNA were detected. The deletion in mRNA is due to a G to A transition in the last nucleotide of exon 8 of the hLAL gene, a splice junction mutation (E8SJM) that resulted in exon skipping, and a predicted in-frame deletion of the 24 amino acids. [35S]Met metabolic labeling studies in fibroblasts showed a low level of E8SJM LAL ( approximately 38%) that was highly unstable. Heterologous expression of E8SJM LAL in insect cells gave an LAL with low catalytic activity toward cholesteryl oleate and triolein. The effects of this mutation are complex with the production of decreased amounts of an unstable LAL that is catalytically defective. The results suggest that E8SJM leads to essentially a null allele and that the differences in WD and CESD phenotype involve other factors.

[The design of the ultrasonic Doppler spectrum analyze system for the naval blood stream of fetus]

The design of the Ultrasonic Doppler Specturm Analyze System for the naval blood stream of the fetus is discussed, mainly on the sampling method of the Doppler signals and the algorithm of the blood stream parameters. Because the DSP chip is not used in the AD cardboard, the hardware design is not only simplified, but also works more steady. In the process of the blood stream parameters, an autochange method of the amplitude threshold and a time-out control technology are used, so the algorithm has good adaptation and works very stable.

Activation of the tobacco SIP kinase by both a cell wall-derived carbohydrate elicitor and purified proteinaceous elicitins from Phytophthora spp

Two purified proteinaceous fungal elicitors, parasiticein (an alpha elicitin) and cryptogein (a beta elicitin), as well as a fungal cell wall-derived carbohydrate elicitor all rapidly activated a 48-kD kinase in tobacco suspension cells. The maximum activation of this kinase paralleled or preceded medium alkalization and activation of the defense gene phenylalanine ammonia-lyase (PAL). In addition, the two elicitins, which also induced hypersensitive cell death, activated a 44- and a 40-kD kinase with delayed kinetics. By contrast, the cell wall-derived elicitor only weakly activated the 44-kD kinase and failed to activate the 40-kD kinase. The size and substrate preference of the 48-kD kinase are reminiscent of the recently purified and cloned salicylic acid-induced protein (SIP) kinase, which is a member of the mitogen-activated protein kinase family. Antibodies raised against a peptide corresponding to the unique N terminus of SIP kinase immunoreacted with the 48-kD kinase activated by all three elicitors from Phytophthora spp. In addition, the cell wall elicitor and the salicylic acid-activated 48-kD kinase copurified through several chromatography steps and comigrated on two-dimensional gels. Based on these results, all three fungal elicitors appear to activate the SIP kinase. In addition, inhibition of SIP kinase activation by kinase inhibitors correlated with the suppression of cell wall elicitor-induced medium alkalization and PAL gene activation, suggesting a regulatory function for the SIP kinase in these defense responses.

Activation of the tobacco SIP kinase by both a cell wall-derived carbohydrate elicitor and purified proteinaceous elicitins from Phytophthora spp

Two purified proteinaceous fungal elicitors, parasiticein (an alpha elicitin) and cryptogein (a beta elicitin), as well as a fungal cell wall-derived carbohydrate elicitor all rapidly activated a 48-kD kinase in tobacco suspension cells. The maximum activation of this kinase paralleled or preceded medium alkalization and activation of the defense gene phenylalanine ammonia-lyase (PAL). In addition, the two elicitins, which also induced hypersensitive cell death, activated a 44- and a 40-kD kinase with delayed kinetics. By contrast, the cell wall-derived elicitor only weakly activated the 44-kD kinase and failed to activate the 40-kD kinase. The size and substrate preference of the 48-kD kinase are reminiscent of the recently purified and cloned salicylic acid-induced protein (SIP) kinase, which is a member of the mitogen-activated protein kinase family. Antibodies raised against a peptide corresponding to the unique N terminus of SIP kinase immunoreacted with the 48-kD kinase activated by all three elicitors from Phytophthora spp. In addition, the cell wall elicitor and the salicylic acid-activated 48-kD kinase copurified through several chromatography steps and comigrated on two-dimensional gels. Based on these results, all three fungal elicitors appear to activate the SIP kinase. In addition, inhibition of SIP kinase activation by kinase inhibitors correlated with the suppression of cell wall elicitor-induced medium alkalization and PAL gene activation, suggesting a regulatory function for the SIP kinase in these defense responses.

EMG study in the diagnosis and differential diagnosis of lipid storage myopathy

Clinical, electromyographic and pathological features were studied in 18 patients with lipid storage myopathy (group I) and 18 patients with polymyositis and dermatomyositis (group II). The results showed a remarkable lower spontaneous activity(SA) incidence (14%) in group I than that (55%) in group II; 46% and 34% short-duration motor unit potentials(MUAPs) with polyphasic potentials and 74% and 71% short-duration MUAPs without polyphasic potentials respectively; the percentages of increased polyphasic MUAPs were same in the two groups. The reduced or pathologic interference patterns accounted for 61% in the group I and 50% in group II. Increased CPK, LDH and HBD were also found in both of them. It is suggested that the lipid storage myopathy may be diagnosed when patients have muscle weakness and myalgia with short-duration and low-amplitude and polyphasic MUAPs without or with occasional spontaneous activities, and increased CPK, LDH and HBD.

The epidemiology study of hyperuricemia and gout in a community population of Huangpu District in Shanghai

OBJECTIVE

To investigate the prevalence of hyperuricemia and gout in a community population of Huangpu District in Shanghai.

METHODS

In the target community, 2037 dwellers were interviewed with relevan questionnares from house to house. According to even house number 1017 blood samples were taken for serum uric acid (SUA) levels measured with the uricase-peroxidase enzymatic method.

RESULTS

The prevalence of hyperuricemia was 14.2% in men (SUA > 70 mg/L, 62 cases), 7.1% in women (SUA > 60 mg/L, 41 cases), 10.1% in both sexes. Seven gout patients were all men. The prevalence of gout in 2037 dwellers in Huangpu District was 0.77% in men and 0.34% in both sexes.

CONCLUSIONS

The mean SUA level in each age group in this survey was much higher than that of a previous study 1 carried out in Shanghai, Beijing and Guangzhou in 1980 (P < 0.05). And the prevalence of hyperuricemia was increased rapidly (in men: from 1.4% in the survey of 1980 to 14.2% in our survey; in women: from 1.3% in the survey of 1980 to 7.1% in our survey). Compared with Idonesia data in 1992, the prevalence of hyperuricemia and gout in our survey was lower than that in Indonesia (P < 0.05), which suggests that racial and genetic predispositions are key causative factors.

Mouse lysosomal acid lipase: characterization of the gene and analysis of promoter activity

Lysosomal acid lipase (LAL) is required for the hydrolysis of intracellular cholesteryl esters and triglycerides that are delivered to lysosomes by low density lipoprotein (LDL) receptor-mediated endocytosis. To understand that the expression of LAL mRNA and protein is tissue and cell specifically regulated in mice, genomic clones for the mouse lysosomal acid lipase (mLAL) gene were isolated and characterized. The 6.8 kb of the mLAL gene 5'-flanking region was sequenced. Comparisons of mouse and human LAL genes organization revealed identical intron/exon boundaries, except for intron 1 of the mouse gene, and identical exonic length of exons 3-9. The transcription start sites and exon 1 of mLAL were characterized by 5'-RACE-PCR and S1 nuclease mapping. Transfection of 5' flanking deletions of mLAL luciferase reporter gene construct identified positive and negative regulatory elements that varied with cell type. Transfection of three progressively smaller pieces of intron 1 inserted into an SV40 promoter and luciferase reporter gene revealed an enhancer-like activity in intron 1 that is also cell type specific. These studies provide insight into the basis for regulation of this critical enzyme in lipid metabolism.